The article is focused on spun concrete made with different chemical admixtures under long-term exposure to aggressive salt-saturated ground water and a cyclic temperature gradient. Over a long-term experimental investigation, 64 prismatic spun concrete specimens were subjected to multicycle (75–120) processing under combined aggressive ambient conditions. Prismatic specimens were soaked in water or saline and dried at a temperature of 45–50 °C. The long-term multi-cycle effect of the temperature gradient and physical salt attack on the compressive strength, Young’s modulus and durability of concrete was found to be negative. Chemical admixtures, though, improved the structure of spun concrete, thus having a significant positive effect on its physical-mechanical properties and durability. Corrosion of the protective layer of concrete reinforcement and the subsequent corrosion of the reinforcement are the main reasons that reinforced concrete structures deteriorate before their time. Metal corrosion products peel off the protective layer, the corrosion of the metal reduces the cross-section of longitudinal and transverse reinforcement, and the transverse reinforcement breaks, resulting in irreversible decay.res, hardening conditions, compaction degree, alternating wetting and drying conditions, freezing and thawing, bacterial corrosion and attacks by various chemicals . However, the corrosion of concrete by physical salt attack from saline groundwater is one of the most dangerous and aggressive factors and leads to significant financial losses.The scientific literature deals with a number of factors related to the corrosion of concrete: residual water–cement ratio (W/C)Deterioration from physical salt attack (PSA) occurs when crystallized groundwater salts  accumulate in concrete pores and build up pressure. Such salt weathering is most commonly observed in arid climates such as in North Africa, the Middle East, a few American states and Australia .The cyclic wetting and drying of saline in hardened cement paste appears to cause the most destruction because it allows salts to migrate to the evaporating surface through capillary action. Subject to the structure of the paste, salt crystallization can occur directly on its surface or within a certain layer. In the first case, the concentration of calcium hydroxide in the adjacent layer of hardened cement paste gradually decreases since its solubility increases in the presence of salts, thereby causing type 1 corrosion.If the size of the pores is large enough (≥0.2 μm), water evaporation occurs on the surface of the product and in the pores of the surface layer of the concrete. Next, salt crystallizes in the pores of the hardened cement paste, leading to its deterioration (corrosion type 3).Although the mechanism of concrete fracturing is not completely clear, there are several hypotheses about the causes of the deterioration of hardened cement paste under the impact of saline in the presence of surface evaporation .One of the first hypotheses about the salt crystallization pressure within the pores of hardened cement paste was that it was due to growing tensile stresses. The reliability of this hypothesis is questionable on the grounds that the crystallization pressure is insignificant and cannot be the only reason for the cement paste deterioration.A second hypothesis suggests that deterioration caused by potassium salts occurs due to an increase in the volume of neoplasms. As a result, along with the accumulation of salts in pores, internal stresses arise that cause crack formations, which contribute to the penetration of an aggressive medium deep into the concrete. Deterioration may also occur because of the wedging action of water when concrete is saturated with saline, which generates alternating stresses under cyclic wetting and drying, osmotic forces and differences in the coefficients of the thermal expansion of hardened cement paste and salts.According to a third hypothesis, the main reason for the deterioration of hardened cement paste subjected to cyclic wetting with saline and drying is an increase in the volume of salt crystals at the conversion phase from less to more hydrated. Drying concrete at a temperature above the point of phase conversion of salts followed by wetting it at a lower temperature, accompanied by the formation of expanding crystalline hydrates, is accepted as the most destructive state.None of the above hypotheses provides an exhaustive explanation for the deterioration process of hardened cement paste under the aggressive action of saline characterized by the complexity of the phenomena in this particular case. Apparently, the corrosion mechanism is determined by a combination of all the abovementioned factors. The natural operating conditions of structures frequently involves several unfavourable factors such as aggressive saline groundwater, temperature fluctuations during the day, and dry winds causing the capillary migration of saline groundwater into the concrete of the structure.The scientific literature provides a number of studies on factors having an impact on concrete durability, including physical salt attack (PSA) ,11,12,13The clear majority of studies deals with durability and reliability of vibrated concrete ,30,31,32The impact of PSA and CWD on the physical–mechanical properties of vibrated concrete is considered in the research papers that state that exposure to saline initially improves the structure of concrete ,37, whilExperimental results presented by Liu et al.  showed tThe operating temperature of a concrete structure and its gradient during the day is another very significant factor that determines its durability and is closely related to the abovementioned one. The surface temperature of a structure often varies from +60 °C during the day to −20 °C at night time  and leads to elongation–shortening (swelling–shrinkage) strains leading to concrete destruction. The same swelling–shrinkage strains of hardened cement paste due to the wind-induced capillary filtration of groundwater are caused by wetting–drying in the contact zone with the ground.A detailed analysis of climate changes having an impact on the deterioration of concrete infrastructure is presented in . DespiteThe researchers investigating the impact of an operating temperature on the properties of vibrated concrete noted that the long-term effects of the temperature gradient on the mechanical properties of concrete was negative and subject to the composition of the concrete mix (water–cement ratio), the magnitude of the temperature gradient and the frequency of variations, groundwater aggressiveness , capillary soil–water migration in concrete, the humidity of the environment, and wind intensity ,42,43,44In a review of the literature, D.J. Naus found that concrete showed a slight loss of strength when the steady-state temperature rose from 20 to 200 °C. In the case of seasonal and daily periodic variations in temperature, the situation was quite different . CyclicaThe adverse atmospheric factors  frequently affected the reinforced spun concrete supporting poles of overhead power transmission lines .The previous studies conducted by the authors demonstrated that the compressive strength and Young’s modulus of spun concrete decreased by 20–40% following 75 cycles of wetting in water and drying in the air at 100 °C, and the mechanical properties decreased to a similar extent. Actually, this was significantly influenced by a large temperature gradient (Δt ≈ 80 °C) formed during the wetting–drying cycle .Using concrete admixtures to produce denser concrete is one method of increasing the service life of reinforced concrete structures under the aggressive ambient conditions mentioned above. The selection of appropriate admixtures depends on the granulometric and chemical composition of coarse aggregates, cement and sand in the area, the method of compaction and hardening of reinforced concrete elements, and the chemical admixtures produced mainly from industrial waste in the region ,47,48. TThis article analyzes the impact of long-term physical salt attacks (PSAs) and an exclusively multicyclical temperature gradient on the mechanical properties of spun concrete modified by chemical admixtures. The research to be continued also covers other unfavourable impacts on spun concrete.Portland slag cement having a compressive strength of 40 MPa was used. Its main physical and mechanical properties are presented in To prepare the concrete mix, sand consisting of particle sizes from 0.14 to 1.25 mm was used as a fine aggregate, and granite rubble of 2.50 to 25.00 mm was employed as a coarse aggregate. The maximum content of particles from 20 to 25 mm in diameter made was 10% by weight. The maximum particle size of the coarse aggregate conformed to technological and design requirements of not exceeding 1/3 of the wall thickness of thin-walled specimens. The physical and mechanical properties of the aggregates are given in Potable water from the water supply system was used to produce the concrete mix.Three types of superplasticizers were used to investigate the impact of chemical admixtures on the physical and mechanical properties of spun concrete .The effective amount of the admixtures was based on previous research performed by the authors . All adm3, respectively. Due to the centrifugation process, part of water and cement admixtures were washed from concrete mixtures. Therefore, the initial water–cement ratio varied from 0.29 to 0.37 and decreased to the residual water–cement ratio of 0.28–0.30. The compositions of the concrete mixes, including chemical admixtures, were selected to make the consistency of the concrete mix similar to that of the concrete mix prepared without admixtures. This was achieved by varying the water–cement ratio. The contents of the chemical admixtures and the initial water–cement ratio (W/C)in in the concrete mix are given in For durability studies on spun concrete, specimens were obtained from heavy concrete having a compressive strength of 60–70 MPa. The sand, crushed stone, cement and water components in concrete mixtures were 400, 1280, 565 and 164–209 kg/mThe composition of concrete mixtures prepared without chemical admixtures corresponded to those used to manufacture spun poles for overhead power lines and provide a compressive strength of spun concrete of 60 MPa.Manufacturing specimens to test the effect of salts and temperature on the resistance of spun concrete covered 2 stages. This study used 42 thin-walled circular cross-section specimens, the main geometrical parameters of which were a height of 550 mm, outer diameter of the annular cross section of 560 mm, and wall thickness from 75 to 90 mm. In this case, metal moulds with an inner diameter of 560 mm and a length of 23,100 mm for producing the spun concrete supporting poles were employed. To mould the prototypes to a predetermined height of 550 mm, special metal diaphragms were used.The metal mould contained 4 types of concrete mixes, 11 specimens of which were obtained from the admixture-free concrete mix using the Dofen superplasticizer. Ten specimens were moulded from the concrete mix containing superplasticizers C-3 and ACF-3M.rotating for 3 min until 50–80 rev/min was reached,rotating for 1 min until 150 rev/min was reached,rotating for 1 min until 200 rev/min was reached,rotating for 1 min until 300 rev/min was reached,compaction for 15 min when 420–442 rev/min is reached.The specimens were produced by applying a roller-type centrifuge to manufacture the supporting poles of overhead power transmission lines. To form the specimens, the following centrifugal consolidation mode was applied:2 h at 20 °C;2 h rising to 75 °C;3 h at +75 ± 5 °C;2 h at a falling temperature.The total time for the concrete compaction process employing centrifugation was 21 min. The metal mould filled with spun concrete was heat-treated in keeping with the following mode:The heat treatment of spun concrete took place in an induction chamber. Heating the concrete, made of reinforced concrete products, was carried out by heating a metal mould and reinforcing it in an electromagnetic field.Part of the circular cross-sectional specimens a was cutInvestigation of the resistance of spun concrete to different types of severe ambient conditions was carried out in two stages following 75 or 120 cycles of CWD.The following modes of aggressive ambient conditions were applied to the abovementioned technique for testing spun concrete specimens:1. Alternate drying of specimens under ambient air conditions for 11 h at a 45–50 °C followed by ambient cooling at 18–22 °C, and by wetting in water for 12 h at 20–25 °C.2. Alternate drying of specimens under ambient air conditions for 11 h at 45–50 °C followed by ambient cooling at 18–22 °C, and by wetting in saline for 12 h at 20–25 °C.To completely eliminate additional hydration of cement within the process of wetting the hardened cement paste, integrated (combined) tests on spun concrete were carried out for more than one year.The composition of saline for creating an aggressive salt solution environment under laboratory conditions was chosen considering the results of the chemical analysis of ground water in the region of servicing reinforced spun concrete members—supporting poles of overhead power transmission lines .It should be noted that the severe ambient conditions  were in contact with only the outer side of the supporting pole. Therefore, to fully reflect the one-sided action of saline under laboratory conditions before testing both ends of the prismatic specimens, three lateral surfaces  were waterproofed with 5 coats of polyvinyl acetate (PVA) glue. Next, the specimens were submerged in a specially equipped container filled with saline or water (subject to the mode of aggressive ambient conditions) for up to 24 h.α and β [E, respectively. These dimensionless coefficients characterized the degree to which the initial mechanical properties of spun concrete were preserved. The degree of preservation (resistance coefficient) was the ratio of the indicators for the mechanical properties of the exposed concrete to those of the concrete that was not exposed. The study determined the experimental values the coefficients to the impact of the various aggressive ambient conditions.The resistance of spun concrete to aggressive ambient conditions was estimated by the concrete resistance coefficients α and β : the estConsidering that manufacturing the spun concrete specimens involved the use of different chemical admixtures, and that durability testing disclosed the varying effects of the ambient conditions, conditional three-digit indices were adopted to indicate the mechanical properties. Each index shows the type of the chemical admixture used and the temperature and wetting process of the basic specimens.The first digit of an index denotes the grade of the chemical admixture:0. Admixture-free concrete mix.1. Concrete mix containing acetone-formaldehyde resin ACF-3M;2. Concrete mix containing superplasticizer ‘Dofen’;3. Concrete mix containing superplasticizer C-3.The second digit denotes the temperature of environmental exposure:0. Specimens are stored at an air temperature of 18–22 °C;1. Specimens are dried at an air temperature of 45–50 °C.The third number denotes the ambient conditions under the wetting mode of the main specimens at 20–25 °C:0. Normal temperature and humidity.1. Water.2. Saline., and The resistance of spun concrete to temperature variations was estimated with reference to the coefficients:The assessment of the resistance to the integrated (simultaneous) impact of several types of the aggressive ambient conditions plays an important role in analyzing the durability of concrete. The tests were aimed at investigating resistance to the integrated aggressive condition of saline and temperature variations. The durability was estimated by employing the coefficients:Resistance to the corrosive effects of salts is one of the main determinants of durability under dry and hot climatic conditions. In deserts, the underground parts of reinforced concrete and concrete structures used as supports are subjected to concrete corrosion class 3, which combines all interactions with the environment. These processes are related to the formation and accumulation of poorly soluble salts. An increase in the volume of salts during conversion to the solid phase  causes internal stresses and destructive phenomena. Similar occurrences may take place as a result of the crystallization of reaction products and salts in the pores of hardened cement paste coming from the outside in the form of a solution. The rate at which the processes proceed largely depends on temperature. Thus, in the hot climate of a desert, corrosion class 3 progresses much faster than at low temperatures under other harsh climate conditions.Unfortunately, current standards do not provide a method to determine the resistance of concrete to corrosion. In this case, the well-known technique introduced by Skramtaev  appears Thus, the authors of the present study agreed to exclude temperature when identifying the impact of salt crystallization on the mechanical properties. The achieve this goal, improvements were made to the testing methodology and technique for assessing corrosion resistance. In contrast to the resistance tests described by the authors in , the dryTo calculate these coefficients, the compressive strength or the initial Young’s modulus of spun concrete was prepared using the same admixture of concrete mix and the results of soaking in an equal number of cycles in saline and water were compared. After wetting, the specimens were air-dried at the same temperature.The main parameters of the cross-sections and the results of short-term axial compression tests on control (not subjected) prismatic specimens and those subjected to different aggressive environments are given in The results of the previous study used to compare the results of the experimental study were published in the . The exp1 and β1 as shown in Testing results following 75 and 120 cycles of alternate drying of concrete in the air and wetting in water show that the presence of temperature variations, although very small (Δt ≈ 25°) but lasting a long time (with a large number of CWD cycles), has a negative effect on the mechanical properties and thus durability. This is shown by the experimental values of the resistance coefficients αα1 made with admixtures Dofen, C-3 and ACF-3M fluctuated within a range of 0.83–0.90, and coefficient β1 varied within a range of 0.91–0.99. As for traditional spun concrete, these coefficients were 0.85 and 0.80 respectively. Overall, a small temperature gradient Δt ≈ 25 °C following 75 wetting and air-dried cycles slightly reduced the strain index of concrete containing admixtures [The analysis of the results demonstrated that the chemical admixtures had a significant positive effect on the resistance of spun concrete to temperature variations. mixtures . AlthougThe previous experiments conducted by the authors of  and dispThus, a cyclic drop in temperature from 100–105 °C to 20–25 °C had a significantly negative effect on the mechanical properties and durability of the traditional spun concrete (control), which explains the “jump” in the experimental data diagram in α1 produced with admixtures Dofen and C-3 varied within the range of 0.75–0.78, while the resistance coefficient of the traditional spun concrete and the one containing the ACF-3M admixture was 0.64–0.69. A similar situation was observed for coefficient β1: 0.78–0.81 for concrete with admixtures Dofen and C-3 and 0.61–0.68 for admixture-free concrete or containing the ACF-3M admixture, respectively.From the preceding, it can be concluded that a drop in the temperature gradient seen during the experiments failed to completely exclude the impact of temperature on the mechanical properties.Alternating drying in the air and wetting in water showed that the magnitude of a negative impact on the mechanical properties was subject to the number of CWD cycles and the gradient of temperature variations throughout the wetting–drying processes.The nature of changes to the indicators of durability depending on the number of CWD cycles suggested that the microdefects identified in the concrete structure and caused by the presence of temperature differences in the environment prevented the different types of concrete from having a denser structure .After 75 cycles of CWD, concrete containing admixtures C-3 and Dofen tended be suppressed, whereas the admixture-free concrete and that produced with ACF-3M still developed intensively. At some point between 75 and 120 cycles of CWD, the above-mentioned negative impact of the temperature gradient started to manifest much more rapidly and the decrease in the resistance coefficients  of 5–7% .The reason that the destruction of concrete with admixture ACF-3M developed similarly to that of admixture-free concrete can be explained by considering the composition of the concrete mix . The iniTo assess the resistance of spun concrete to the integrated effects of temperature variations and saline, data on the effect of chemical admixtures on the mechanical properties of spun concrete were obtained and are presented in In the presence of the integrated effect of saline and temperature variations , a negative effect of the latter on the mechanical properties was observed: the formation of microcracks along the entire structure and smoothed by the positive impact on the stress and strain properties by newly formed salt crystals in the microcracks and pores The microcracks appeared between the coarse aggregate, which accumulated on the outer surface of the product during centrifugation and on the layer of cement paste due to the effect of the cyclic temperature difference, as a result of which the saline solution penetrated. It crystallized, accumulated and caused internal pressure, thus increasing the crack and peeling of the coarse aggregate from the hardened cement paste.α2 and β2 according to (3) and (4) respectively.The integrated effect of the above-mentioned factors on the mechanical properties was estimated by resistance coefficients α2 was greater than α1. Following 75 cycles of CWD, coefficient β2 was also higher than β1. In addition, coefficient β2 was greater than 1 for all types of spun concrete tested. Following 75 cycles of CWD, the compressive strength of the concrete containing the chemical admixtures decreased to 10%; meanwhile, the compressive strength of admixture-free spun concrete was 10% higher than that of the control specimens.This confirmed the conclusion that saline––the crystallization of new formations in the pores and micro-cracks of concrete––increased the strength of spun concrete up to a certain number of CWD cycles. The same situation was observed discussing the initial Young’s modulus of spun concrete exposed to saline and temperature variations. In the case of the combined effect of the temperature gradient and saline, at some point between 75 and 120 cycles (or possibly earlier), compressive strength and the initial Young’s modulus showed a greater negative effect from the temperature gradient rather than a positive effect from salt crystallization in concrete pores. The results below confirm this statement.As indicated by the previous experimental studies , Figure To assess the resistance of spun concrete to salt corrosion the coefficients were been determined considering the results of the tests performed at a reduced drying temperature. The values were calculated by applying formulas (5) and (6) and are given in α3 = 1.28, β3 = 1.34, while those of concrete containing C-3 or Dofen admixtures were 1.08 and 1.07–1.10 respectively.The increase in these indicators under the impact of showed that the use of admixtures made it possible to reduce the initial water–cement ratio of the concrete mix, which resulted in denser and more homogeneous structure .A spun concrete product has an outer surface that is dense and has low-porosity, which is the opposite of its inner surface. Centrifugation, a specific method for compacting a concrete mix, pushes larger particles to the outer wall of the formwork while the smaller ones face the cylindrical hole at the centre of the cross-section. In addition, centrifugation expels excess water from the concrete mix towards the inner surface. As a result, microcapillary voids are formed in the cross-section and directed from the outer surface towards the centre, which further reduces the density of the inner layer.Salt crystallization in the pores takes place under the influence of saline, as a result of which the concrete acquires a more homogeneous structure, particularly in the inner, more porous surface. For more heterogeneous and porous concrete, salt crystallization has positive effect of on the stress and strain properties up to a certain number of cycles. The data provided in Temperature drops and alternate swelling–shrinkage under cyclic wetting–drying have a negative effect on the mechanical properties of concrete and may cause micro-cracks, the magnitude of which mainly depends on the temperature gradient at CWD.However, Under a large number of CWD cycles, the process of micro crack formation in concrete actually stops, and a positive effect of corrosion class 3 on the stress and strain properties of concrete (removing defects) turns into the negative one since an adverse effect of the pressure of growing salt crystals on the walls of pores and micro cracks in concrete is observed.Thus, it is assumed that a further decrease in the indicators describing the mechanical properties of concrete and the intensity of concrete destruction will be subject to the concentration of saline (groundwater), the value of the temperature gradient and the number of CWD cycles.Experimental methods have involved revealing a long-term negative cyclic effect of the temperature gradient on compressive strength, Young’s modulus and durability of spun concrete. The decrease in compressive strength and Young’s modulus depended on the temperature gradient and the duration of the cyclic effect, which, along with the induced swelling–shrinkage (elongation–shortening) strains may cause damage to the concrete structure.Following 120 cycles of concrete wetting in water and drying in the air at a temperature of approximately 25 °C, the temperature gradient on average reduced the compressive strength of admixture-free spun concrete by 35% and the Young’s modulus by 40%.The compressive strength of spun concrete containing admixtures—superplasticizers C-3 and Dofen and decreasing the initial water–cement ratio—was reduced to 25% and the Young’s modulus to around 20%. Meanwhile, the spun concrete containing the admixture ACF-3M only slightly reduced the initial water–cement ratio of the concrete mix, which led to a drop in compressive strength and the Young’s modulus of approximately 30%.The impact of salts dissolved in water was found to produce a dual effect on the compressive strength and strains. Cyclic wetting and drying in saline improved the physical–mechanical properties of concrete at the initial stage of the process, which is the reason that, over time, salt crystallization occurred in the pores and microcracks of concrete that had a different prehistory of development, including cracks that originated from cyclic variations in temperature. The long-term integrated effect of temperature variations and saline on concrete showed that a positive effect of corrosion class 3 on the stress and strain properties turns negative because of a more pronounced effect of the pressure of growing salt crystals on the wall of the pores and microcracks in concrete. Following 120 cycles, the compressive strength of spun concrete containing admixture ACF-3M and that of admixture-free spun concrete under the impact of temperature variations and CWD decreased by approximately 40% and that of the Young’s modulus by around 25%. The compressive strength and Young’s modulus of concrete with admixtures C-3 and Dofen were reduced by 30 and 25% respectively.The resistance of spun concrete to corrosion was found to be mostly subject to the parameters for the concrete structure, i.e., the volume of pores and microcracks in concrete. Chemical admixtures that improved the structure of spun concrete had a significant, positive effect on the mechanical properties and hence durability.


The use of a carbazolyl‐connected di‐gold(I) metallotweezer for the encapsulation of several electron‐poor organic substrates, and a planar Au(III) complex containing a CNC pincer ligand, is described. The binding affinity of the receptor depends on the electron‐deficient character of the planar guest, with larger association constants found for the more electron‐poor guests. The X‐ray diffraction molecular structures of two host:guest adducts show that the host approaches its arms in order to facilitate the optimum interaction with the surface of the planar guests, in a clear example of an guest‐induced fit conformational arrangement. The electrochemical studies of the encapsulation of N,N’‐dimethyl‐naphthalenetetracarboxy diimide (NTCDI) show that the redox active guest is released from the receptor upon one electron reduction, thus constituting an example of redox‐switchable binding. A di‐gold metallo‐tweezer is used as receptor of a series of electron‐deficient planar organic guests, including three organic molecules and two square‐planar metal complexes. The host adapts its shape to maximize the attractive interaction with the guests. Redox‐active guests are released upon one electron reduction, thus this tweezer constitutes an interesting example of redox‐switchable binding. In the 1990s several research groups around the world reasoned that U‐shaped molecules with aromatic side walls would form rigid and highly preorganized concave cavities suitable for hosting aromatic guest molecules through π‐π stacking interactions.1 showed a great tendency to self‐aggregate in non‐polar solvents and in the presence of cations such as Cu+, Ag+ and Tl+.2 showed interesting coordinating abilities that were highly dependent on the type of metal used. In o3. We thought that the electron‐rich environment provided by the pyrene moieties in complex 3 could be used for encapsulating planar electron‐deficient organic molecules such as N,N′‐dimethyl‐naphthalenetetracarboxy diimide , 2,4,7‐trinitro‐9‐fluorenone  and 2,7‐dinitro‐4‐methoxy‐fluorenone (6). We deliberately obtained 6 from 5  to study if the replacement of one electron‐withdrawing nitro group by an electron‐donating methoxy group would have any measurable influence in the binding affinity of the guest. Together with these three organic guests, we also studied the binding affinities of the two square planar Pt(II) and Au(III) complexes 7 and 8.Scheme 3 and compounds 4–8, we performed 1H NMR titrations in CDCl3 at a constant concentration of 3 (0.5 mM). In general, the NMR titrations showed that the addition of the guests induced perturbations in several resonances of the protons of 3. In particular, the signals due to the protons of the pyrene moiety and the resonance due to the methylene group bound to the nitrogen of the imidazolylidene of 3, were shifted upfield upon addition of the different guests. Only in the case of the titrations with 5 and 6, it was observed that the resonance of the proton bound to the nitrogen of the carbazolyl linker was shifted downfield by 0.9 and 0.2 ppm, respectively, suggesting that for these two guest molecules the formation of the host‐guest complex may be stabilized by the presence of hydrogen bonding interactions, most likely with the oxygen atoms from the nitro groups of the guests. In the case of the titration with the Pt(II) complex 7, the titrations did not show changes in the spectrum of 3, thus indicating that for this guest the formation of an inclusion complex was not detected. Based on the changes observed for the titrations with all other four guests, the association constants were determined by global fitting analysis.7<8<6≪4<5 as can be observed from the values shown in Table 5) and NTCDI (4) are in agreement with the stronger electron‐deficient character of these two planar molecules. Interestingly, the replacement of one of the nitro groups in 5 by a methoxy group results in a dramatic decrease of the association constant, as can be observed comparing the constants shown for 5 and 6  complex 7 did not show any measurable binding affinity with 3. This result may be ascribed to the larger steric hindrance produced by the DMSO ligand bound to 7, which makes the complex deviate from being fully planar. The solubility of both 3 and 8 allowed to perform a 1H NMR titration in toluene‐d8, and the association constant that resulted from the nonlinear fitting of the corresponding binding isotherm was 687 M−1, therefore significantly larger than the one obtained in CDCl3. The results shown in Table 3 is an effective receptor of electron‐poor planar molecules, showing larger binding affinities than other molecular receptors for the same guests. For example, the constant found for the encapsulation of TNFLU is significantly larger than the association constants shown by other molecular tweezers with electron‐rich arms for the same guest under the same experimental conditions,7 and 8.8 was found to be logK=4.43 under the same experimental conditions where we obtained an association constant of 118 M−1 for the encapsulation of the same metal complex with 3.8@3.To quantify the binding affinities between 4@3 and 6@3 were obtained by slow diffusion of hexane into CHCl3 solutions containing equimolecular amounts of 3 and the electron‐deficient guest molecules. The molecular structures of these two host‐guest adducts  were not large enough to produce significant amounts of the host‐guest complexes at the concentrations used to perform Uv‐Vis and emission spectra (10−4–10−5 M), and therefore we discarded these spectroscopic techniques for our studies. On the other hand, the working concentration conditions of cyclic voltammetry (1 mM), allow significant formation of the host‐guest complexes for the cases of 4@3 and 5@3, as can be confirmed from the speciation profiles resulting from the NMR titrations (see supplementary information file). Electrochemistry studies constitute very efficient tool for providing information about the changes in the magnitudes of the intermolecular forces between guest and host upon gain or loss of an electron by either of the components of the host‐guest complex.We wanted to have an estimation of the charge transfer produced in the interaction between the electron‐donating host and the different electron deficient guests upon host‐guest formation. Unfortunately, even the highest association constants that we found (in the range of 104) shows one quasi‐reversible reduction wave between 0‐(−1) V, prior to the irreversible reduction of 3, which occurs at −1.42 V. Upon addition of the metallotweezer 3 to a CH2Cl2 solution of NTCDI the reduction wave retains its reversible shape, but is shifted gradually to more negative values , which diffuses more slowly than free NTCDI. The maximum potential shift can be related to the ratio of the binding constants of the oxidized (Kox) and reduced (Kred) states as given in Eq. 1,red/Kox ratio is 0.011 (Kred=23 M−1) strongly suggesting that the guest is fully released upon one electron reduction.NTCDI  complex (8) has also been demonstrated. The encapsulating properties of the receptor are justified by π‐π attractive interactions, although we also showed that hydrogen bonding plays an important role in the case of the encapsulation of the nitro‐containing molecule TNFLU. A remarkable feature of this molecular tweezer is that it can adapt its shape to maximize the face‐to‐face overlap with the surface of the guest, as shown by the approach of the two pyrene moieties that constitute the tweezer arms from the 10 Å of the empty tweezer, to 7 Å in the case of the tweezer with an encapsulated planar guest. This guest‐induced fit distortion allows that the pyrene moieties of the receptor are disposed at a quasi‐parallel orientation and establish the optimum distance for an effective π‐π‐stacking interaction with the guest molecule.In summary, we have shown that the di‐gold metallotweezer 3 in its neutral state, but it is released upon one electron reduction, thus constituting an interesting example of redox‐switchable binding.Finally, the encapsulation of the redox‐active species NTCDI can be controlled electrochemically, as it displays a large binding affinity with the molecular tweezer The authors declare no conflict of interest.As a service to our authors and readers, this journal provides supporting information supplied by the authors. Such materials are peer reviewed and may be re‐organized for online delivery, but are not copy‐edited or typeset. Technical support issues arising from supporting information (other than missing files) should be addressed to the authors.SupplementaryClick here for additional data file.


Immunoglobulin (Ig) G4-related disease (IgG4-RD) is a group of chronic relapsing inflammatory conditions. Although IgG4-RD can occur in various organs, it is rarely observed in mammary glands. Here, we report a case of IgG4-related mastitis (IgG4-RM) that needed to be differentiated from breast cancer. A 54-year-old woman was examined for a tumor in her left breast. Mammary ultrasonography revealed an irregular hypoechoic tumor measuring 45.0 × 43.0 × 32.0 mm in size. A core-needle biopsy of the left breast tissue revealed a high degree of mixed T and B lymphocytic and plasma cell infiltration, as well as interstitial fibrosis. IgG4-RD was diagnosed based on hematological examination that revealed an abnormal IgG4 value of 332 mg/dl. All the clinical diagnostic criteria for IgG4 were met, resulting in a definitive diagnosis of IgG4-RM. Immunoglobulin (Ig) G4-related disease (IgG4-RD) is a group of chronic inflammatory conditions , 2 and iA 54-year-old woman presented with a tumor in her left breast. The patient had no relevant medical or family history. During physical examination, an elastic hard mass measuring ~6 cm in size was palpated in the upper-outer area of the left breast . An induIgG4-RD represents a group of multisystem, mass-forming entities with increased serum and tissue IgG4 levels and characteristic histomorphological findings such as dense lymphoplasmacytic infiltration, storiform fibrosis and obliterative phlebitis , 2, 4–6.IgG-RD is frequently observed in the pancreas, lacrimal gland and salivary gland, whereas reports of IgG-RD affecting the mammary gland are rare , 7. The Steroid therapy is considered the first-choice treatment for IgG4-RD . The recIn conclusion, we have reported a rare case of IgG4-RM requiring differentiation from breast cancer alongside a discussion of the literature.


FT-IR, SEM, XRD, DLS, and TGA analyses evaluated physicochemical characteristics of the nanocomposite. In addition, the cellular uptake property of the nanocomposites was examined by the HepG2 cells. The outcomes of cell viability results indicate that the nanoparticles loaded with MET&CPT showed the lowest concentration rate of HepG2 and Caco-2 cells compared to the drug-loaded single nanocomposite groups and free drugs. The histological analysis has demonstrated relatively safe and does not produce different stress such as swelling and inflammation of the mice organs. Our results show the enhancement in cytotoxicity in HepG2 and Cocoa-2 cells by MET and CPT graphene oxide-based nanocomposite by promoting apoptotic response. Moreover, Fe3O4@rGO-G-PSEA showed potent in vivo antitumor efficacy but showed no adverse toxicity to normal tissues. Together, this study can provide insight into how surface embellishment may tune these nanocomposites' tumor specificity and provide the basis for developing anticancer efficacy.Hepatocellular carcinoma (HCC) is widespread cancer with a high degree of morbidity and mortality in individuals worldwide and a serious concern for its resistance to present chemotherapy drugs. In this investigation, the combination of cisplatin (CPT) and metformin (MET) to kill the HepG2 and caco-2 cells was developed into a new pH-responding magnetic nanocomposite based on reduced graphene oxide. Polyhydroxyethyl methacrylic (PHEA) was then linked employing grafting from approach to the reduced graphene oxide by ATRP polymerization (Fe People with hepatocellular carcinoma (HCC) have a 5-year survival rate of barely 18% and are the second deadest tumor in the world since pancreatic cancer  is a remarkable biocompatibility and blood compatibility among the polymers examined over past years. On the graphene surface oxide, several binding strategies  has been widely studied in pilot studies and randomized controlled clinical trials as a therapy for NAFLD/NASH. A mixed bag of findings came out of the experiment. Alanine aminotransferase levels are lower, and insulin sensitivity is increased with metformin  is achieved by transforming PHEA hydroxy groups into succinyloxy groups. The interaction of its hydroxy groups with the carboxylic acid groups Poly is then absorbed onto the surface by the iron oxide nanoparticles (SEMA). Metformin and cisplatin are also influenced by ionic interaction, stacking, and bonding to hydrogen on nanocomposite. Finally, HepG2 and Caco-2 hepatocellular cell cancer cells examined the potential in combination chemotherapy in this new approach .2.2.1.3.6H2O, 99%), ferrous chloride tetrahydrate , sulfuric acid (H2SO4), sodium nitrate (NaNO3), dimethyl sulfoxide (DMSO), potassium permanganate (KMnO4) and graphite were purchased from Aladdin Reagents . Thiazolyl blue tetrazolium bromide (MTT), fetal bovine serum (FBS), rhodamine B, Roswell Park Memorial Institute 1640 growth medium (RPMI 1640), AO-EB, HOECHST 33342, Penicillin-streptomycin (100X), and EDTA 0.25% (1X) were purchased from Gibco Invitrogen. The other solvents and reagents were obtained from Sinopharm Chemical Reagent and used without further purification.Cisplatin (CPT), metformin (MET), 2-bromoisobutyryl bromide, succinic anhydride, N, N,N,N, N-pentamethyldiethylenetriamine (PMDETA), 2-Hydroxyethyl methacrylate (HEMA), triethylamine (TEA) were purchased from TCI and used as received. Sodium bore hydride (NaBH4), ferric chloride hexahydrate (FeCl2.2.2SO4 (180 ml), and NaNO3 , in a flask and stirred at room temperature for around 30 min (R.T). The mixture, as mentioned above, was then eaten and mixed for KMnO4  at 35 °C for 7 h. KMnO4  were subsequently added into the reaction mixture, and a further 12 h at the same temperature continued to stir. The reaction blend of the dilution of the GO blend and reduction of the reactive KMnO4 was finally filled with 500 ml of deionized water and 30 ml of hydrogen peroxide (30 wt%). Hydrochloric acid (HCl) (1 mol−1) rinsed the product. Centrifugation and drying at 60 °C were carried out at the suspension  to a reaction tube containing N, N-dimethylformamide (DMF), which was then sonicated for 30 min. Next, 2-Bromoisobutyryl bromide (0.5 mL) was added to the reaction tube, kept under argon protection, and agitated at room temperature for about 24 h. After that, the mixture was centrifuged to precipitate it, and it was washed with double distilled water before being dried in a hot air oven at R.T.2.5.rGO-Br (79 mg) and 5 mL dimethylsulfoxide (DMSO) were poured into a flask. The solution was sonicated for 50 min with a bath-type sonicator to obtain a homogenous suspension of rGO-Br. After that, the flask was loaded with HEMA monomers (5.4 g), PMDETA (76 l), and CuBr (58 mg) to begin the reaction. Several pumps–thaw cycles were performed on the reaction mixture to expose it to argon flow. The reaction mixture was then agitated at 75° C under argon shielding for 24 h. The final products were centrifuged and put into 100 mL of cold methanol before drying in a vacuum oven at 25° C.2.6.The esterification process was responsible for forming succinic anhydride from the reaction of hydroxyl groups in PHEA. The flask was charged with the following ingredients: rGO-g-PHEA (0.3 g), succinic anhydride (0.3 g), and anhydrous pyridine (8 mL). The reaction mixture was stirred at R.T. for roughly 2 d under argon flow to achieve the desired reaction rate. Then, to remove any remaining succinic anhydride, the product was mixed with 25 mL of methanol before being dried under reduced pressure at 25 °C.2.7.2.4H2O, 99% (0.1 molL1), and 40 mL of FeCl3.6H2O, 98% (0.1 molL1), to the reaction mixture. The temperature of the reaction mixture was then increased to 90° C. Under rapid stirring, 10 mL of ammonia solution (containing 25% ammonium) was promptly added into the reaction mixture to complete the reaction. The resulting suspension was maintained at 80 °C for 1 h while being constantly stirred and then cooled to room temperature. It was discovered that the acquired SPIONs were black sediment that had been rinsed many times with water and ethanol until its pH had changed to neutral and that it had been dried overnight in a vacuum at R.T.The SPIONs were developed using the co-precipitation strategy, which was previously reported. First, the reaction mixture was heated to 80° C after being exposed to a very pure argon flow for 30 min, followed by the addition of 20 mL of FeCl2.8.3O4@rGO-g-PSEA magnetic nanocomposite, 200 mg of rGO/PSEA, 2 mL of DMSO, and 200 mg of SPIONs were charged into a flask and sonicated for 50 min with a bath type sonicator to establish a homogeneous suspension. Next, for approximately 48 h, the solution was dialyzed. Finally, the product was centrifuged for 5 min before drying in a vacuum oven and weighted to finish.To obtain a homogenous solution of Fe2.9.The surface chemical modifications were characterized using Fourier transform infrared spectroscopy . The KBr pellets were processed by mixing 300 μg of the samples with 200 mg of KBr . We characterized the morphologies of the nanocomposites using a TEM . We applied a dynamic light scattering detector  to determine nanoparticles' particle size and zeta potential for the characterization of nanoparticles. The phased nature of the sample was determined by X-ray diffraction .2.10.3O4@rGO-g-PSEA magnetic Nanocomposite that was loaded with MET&CPT. To achieve this goal, 100 mg of Fe3O4@rGO-g-PSEA magnetic nanomaterials was dispersed in 2 mL DMSO using a bath-type sonicator for 30 min, followed by another 30 min of sonication. Then, the MET (5 mg) and CPT (5 mg) were added to the above solution and allowed to sit for 48 h under the dark condition to emulsify. It was then dialyzed against DI water after being placed into a dialysis membrane bag. A magnetic nanocomposite with MET&CPT loading was then collected using an external magnet. The amount of loaded MET and CPT was determined using UV-Vis absorbance at 480 and 310 nm wavelengths for MET and MET CPT, respectively.The membrane dialysis technique was used to construct the Fe2.11.3O4@rGO-g-PSEA magnetic nanocomposite was evaluated. The nanoparticles were placed in incubation and swirled at 250 rpm at 37 °C for an amount of time, after which 2 mL of PBS solution was added and removed at specific intervals. The absorbance of the samples was measured with a UV-Vis spectrophotometer at wavelengths of 310 and 480 nm. The standard curve was prepared to investigate the relationship between the released CP and MET , free MET-CPT combination (2 D), blank nanocomposites (BNCs), single drug-loaded nanocomposites (NCs-MET and NCs-CPT), and co-drug-loaded nanocomposites (NCs-MET&CPT) on HepG2 and Caco-2 cells. Different samples were administered to HepG2 and Caco-2 cells, which were then incubated for 4 h. The cell viability of each treatment group was then determined using the MTT assay technique, which was performed under the previously described process , free MET, MET-loaded Fe3O4@rGO-g-PSMA nanocomposites (Nano MET), combination of MET and CPT in the form of (CPT-MET) and MET&CPT-loaded Fe3O4@rGO-g-PSMA nanocomposites (Nano CPT-MET) on HepG2 and Caco-2 cells was examined by using double staining of acridine orange (AO) and ethidium bromide (EB). According to previously reported protocol, apoptosis and necrosis cells were noticed. Cell HepG2 and Caco-2 cells were treated for a mixture of EB (10 μl) and AO (10 μL) in PBS and were subjected to composites (30 μg/mL) for 24 h. A fluorescence microscope takes on the photomicrograph . This technique has been employed for apoptosis and live-cell qualitative analysis , free MET, MET-loaded Fe3O4@rGO-g-PSMA nanocomposites (Nano MET), combination of MET and CPT in the form of (CPT-MET) and MET&CPT-loaded Fe3O4@rGO-g-PSMA nanocomposites (Nano CPT-MET) on HepG2 and Caco-2 cells was examined by using HOECHST 33342. According to previously reported protocol, apoptosis, and necrosis cells, the damage was observed. Cell HepG2 and Caco-2 cells were treated for a mixture of HOECHST 33342 (10 μg/mL) in PBS and were subjected to composites (30 μg/mL) for 24 h. A fluorescence microscope takes on the photomicrograph . This technique has been employed for apoptosis and live-cell qualitative analysis , free MET, MET-loaded Fe3O4@rGO-g-PSMA nanocomposites (Nano MET), and MET&CPT-loaded Fe3O4@rGO-g-PSMA nanocomposites (Nano CPT-MET), the present research was encouraged for histopathological analysis. Male Balb-c mice  were acquired from the Department of Hepatobiliary Surgery, Binzhou Medical University Hospital, PR. China and maintained under a standardized environmental situation at the ambient temperature of 25 °C. Animals were preserved with humanly health care and supplied with food and water ad libitum. A total of 12 mice were distributed into six groups. All group mice were treated with free CPT, free MET, Nano CPT, Nano MET, and Nano CPT-MET (40 μg/mL), and control group having 200 μL saline were intravenously (i.v.) administrated for every 3 d  by tail vein injection. For the whole experiment, the body weight has been included. The 22 d were measured by the tissue-to-body weight ratio (weight/mg), the liver, heart, kidney, lung, and spleen. The main organs have been dissected and fastened to the histopathological analysis using 10% of formalin embedded in paraffin, cut and stained by Hematoxylin and Eosin (H&E) for standard technology. Pictures were obtained with an optical microscope after staining  22 d after administration. The animals were then randomly assigned. Three times on days 0, 3, and 6, free CPT (5 mg/kg), free MET (5 mg/kg), Nano CPT (5 mg/kg), Nano MET (5 mg/kg), and Nano CPT-MET (5 mg/kg) were administered intravenously into mouse bearings with HepG2 xenografts. Saline, free CPT, and free MET have also been administered to control its therapeutic formulation (5 mg/kg). Bodyweight and volumes of tumors have been observed for 22 d and noticed. Calipers assessed the tumor lengths (L) and widths (W), and the tumor volume by formula V = (L-W2)/2, where W is short of L, was determined. At the end of the experiment, mice were killed by CO2 inhalation . HepG2 has been cultivated to 80% convergence in 90 mm tissue dishes in the human liver cancer cell line. The pellet was resuspended in PBS at a concentration of 4 °C following 5the cell collection to achieve a final concentration of 3 × 103.3.1.−1, the distinctive GO peaks corresponded to the absorption range attributable to the stretching vibration of the etheric epoxy groups of C–O–C and C–O. Also, stretching vibrations of 1637 cm−1 and 1734 cm−1 were observed in the C=C aromatic rings and C=O in a carboxylic acid. In addition, the group hydroxyl was found to have a broad, strong, 3450 cm−1 band. After reduction, the main alterations in the FTIR rGO spectra were the extending aliphatic and aromatic C–H vibrations at 2902–2935 cm−1 and OH stretched at 3450 cm−1 area. Aromatic bands C=C were also substantially enhanced at 1400 cm−1. Also, hydroxylic stretching vibration intensity was improved, and functional oxygen peaks were reduced at 1059 and 1238 cm−1. A decreased O–H banding intensity and the development of the typical C-belt with the C-bromoisobutyryl bromide (C-Br) at 720 cm−1 revealed the successful creation of the ATRP initiator, and the peak of around 2905 cm−1 was shown to the C-H-bond stretching vibration of the C–Br group.GO, rGO, and GO-Br samples FTIR are indicated in −1, C–O to 1370 cm−1, C–H to 1459 cm−1, and CO to 1735 cm−1, respected. At 2800–316 cm−1 area and the PHEA's hydroxyl group, aliphatic and aromatic C–H stretching vibrations were concentrated at 3465 cm−1 due to the wideband. After esterification with succinic anhydride, the FTIR spectrum has changed significantly due to creating additional C–O and carboxylic acid groups, respectively, after synthesizing rGO g-PHEA with succinic anhydride.FTIR spectrum was shown in 3O4@rGO-g-PSEA magnetic nanocomposite samples. FESEM image from GO indicated the layer structure for GO sheets in the whole area with smaller layers in the range of 28.44 nm, as shown in 3O4 was found with a spherical shape on GO plates in the 37.74 ± 4 NM region in rGO-g-PSEA, Fe3O4@rGO-g-PSEA magnetic nanocomposite , 43 (54.4) and 57.16 and 64.04 correspondingly, which corresponds to Fe3O4 crystal (111), (222), (313), (400), (513), and (440). Furthermore, the failure to emerge the peak at 2–26/09 showed that GO was precisely synthesized and that the graphite was changed absolutely from GO. The lack of the decisive peak in the 2–11.21 range, coupled with a vast (002) peak and a shallow (100) peak in the 2–2 versus 25.02–42.39 range, decreased the GO to rGO. Dynamic light scattering (DLS) assigned Fe3O4@rGO-g-PSEA magnetic nanocomposite. The pictures of the nanocomposite with the DLS intensity distribution are shown in 3O4@rGO-g-PSEA was 63.4 nm , which decreases further into the cellular cells, notably into endosomes (5–6) and lysosomes (pH 4–5.0), may result in specific cancers. Consequently, these properties might be employed for the appropriate design and improvement of pH-sensitive nanocarriers' efficiency and therapeutic effectiveness that intelligently separate normal from malignant tissues. We used pH 5.4 to replicate the condition of the tumor endosome. 3O4@rGO-g-PSEA magnetic nanocomposite have been estimated.π–π-stacking interaction between a large π-conjugated GO-conjugation and a quinone component of MET has adhered to GO nanoparticles with metformin (MET). MET is positive at normal pH, whereas carboxy groups are negatively charged on the surface of the particles. Thus, MET could quickly be loaded into polymers through electrostatic interactions and the creation of amide and hydrogen bonds. CPT is related to the polymer and covalent binding of Pt of CPT amine groups of CPT with the Carboxyl group (–COOH), with the nanocomposite group (–COOH). MET&CPT's drug administered behavior in phosphate buffers with the pH 7.4 and 5.4 pH analog of physiological circumstances was described using Fe3.3.3O4@rGo-g-PSEA into hepatocellular cells, HepG2 and Caco-2, was studied. Fe3O4@rGO-g-PSEA 3O4@rGO-g-PSEA and MET&CPT of magnetic nanocomposites loaded with Fe3O4@rGO-g-PSEA. The findings indicated that nanocomposites were time-dependent on the absorption of the HepG2 and Caco-2 cells. The cells absorbed the nanocomposites in the early 1 h, and after 3 h incubation, internalization is adequate. The discovered red fluoridation for cytoplasms shows Fe3O4@rGO-g-PSEA, and MET&CPT loaded rhodamine B labeled Fe3O4@rGO-g-PSEA are primarily examined in the cytoplasm Fe3O4@rGO-g-PSEA  had a higher mortality level than free MET, CPT, and MET&CPT. Compared to similar single forms, the combined forms (MET&CPT and Nano MET&CPT) were also more effective . After 24 h at exposures of 1.94 μg/mL, 35.35 μg/mL, and 1.89 μg/mL, the half limit inhibitory (IC50) concentration of the MET, CPT, and MET&CPT of hepG2 and Caco-2 cells, respectively. In addition, 1.255 μg/mL, 11.01 μg/mL, and 0.798 μg/mL were derived from the IC50 amounts of the MET NPs, CPT NPs, and MET&CPT NPs  over 24 h for apoptosis inductance. The control cells exhibited a typical round integrated nucleus and organized morphology with HOECHST 33342 staining emitting a reduced blue fluorescence . The tre3.7.In vivo investigation of the systemic toxicity effects of nanocomposites on the biological system. We have employed Hematoxylin and Eosin stains from nanocomposites treated tissues from mice for this investigation. This investigation resulted in a gradual loss of weight for cisplatin. Interestingly, the cisplatin-mediated weight reduction was reduced by the combination of metformin and cisplatin. Reduced intake and weight loss in individuals undergoing cisplatin treatment are severe health problems. Relatively, in the nanocomposite mice treated group, no pathological evidence has been identified, and it shows no toxicity for central bodies with nanocomposites. We also collectively conclude that the alterations between the major treatment nanocomposite organs and the saline control group, as illustrated in 3.8.in vivo.All the animal experiments were performed under protocols approved by the Institutional Animal Care and Use Committee (IACUC) of the Department of Interventional Radiology, Beijing Friendship Hospital, Capital Medical University. We next examined the treatment effectiveness of the tumor model with xenograft mice. We have developed the human tumor model HepG2 in Balb/c nude mice for this examination. The tumor volume in each group was recorded after intravenous injection of free CPT (5 mg/kg), free MET (5 mg/kg), Nano CPT (5 mg/kg), Nano MET (5 mg/kg), and Nano CPT-MET (5 mg/kg). As 4.3O4@rGO-G-PSEA) using Poly (hydroxyethyl methacrylate grafted to succinic anhydride). Application for the first time to co-purchase MET and CPT was made to Fe3O4@rGO-g-PSEA nanocomposite. MET (75%) and CPT (82%) simultaneous encapsulation were used on this new system via ion interactions, π-π conjugation, and hydrogen bonding. This new system was developed. The created nanosystems demonstrated a pH-controlled releasing behavior that was concurrently released at pH 5.4 after 24 h, 60 and 50% of CPT and MET. Although at pH 7.4, around 40% and 30% of CPT and MET were released after the same duration. In vitro cytotoxic testing, nanocomposites from Fe3O4@rGO-g-PSEA were not cytotoxic at a 250 μg/mL concentration for HepG2 and Caco-2. Most importantly, after initial exposure (1–3 h), this new MET&CPT-loading nanocomposite Fe3O4@rGO-G-PSEA showed excellent cellular use.A unique stimuli-responsive nanocomposite was developed using graphene Oxide and was then bonded to magnetic nanocomposites (Fein vivo effectiveness of Fe3O4@rGO-G-PSEA was assessed, which was not before reported. Not all Fe3O4@rGO-G-PSEA with excellent in vitro cancer effectiveness have an equal in vivo efficacy. These results have shown that hepG2 and Caco-2 hepatocellular carcinoma cell destruction may be successfully used in the combination therapy.Further, the systemic toxic profile of the nanocomposite reveals that the ideal toxicity property compares to other nanocomposites and free drugs. Moreover, in the present investigation, the


Besides, the results also make evident the presence of GA-NPs inhibitor, ascribed to the consumption of calcium hydroxide, and reduced the Ca/Si to 3.72% and 0.69% respectively. Hence, C-S-H gel was developed and pH was increased by 9.27% and 12.5, respectively. It can be concluded that green GA-NPs have significant corrosion inhibition potential and improve the carbonation resistance of the concrete matrix to acquire durable reinforced concrete structures.The inhibiting effect of Gum Arabic-nanoparticles (GA-NPs) to control the corrosion of reinforced concrete that exposed to carbon dioxide environment for 180 days has been investigated. The steel reinforcement of concrete in presence and absence of GA-NPs were examined using various standard techniques. The physical/surface changes of steel reinforcement was screened using weight loss measurement, electrochemical impedance spectroscopy (EIS), atomic force microscopy and scanning electron microscopy (SEM). In addition, the carbonation resistance of concrete as well screened using visual inspection (carbonation depth), concrete alkalinity (pH), thermogravimetric analysis (TGA), SEM, energy-dispersive X-ray spectroscopy (EDX) and X-ray diffraction (XRD). The GA-NPs inhibitor size was also confirmed by transmission electron microscopy (TEM). The results obtained revealed that incorporation of 3% GA-NPs inhibitor into concrete inhibited the corrosion process via adsorption of inhibitor molecules over the steel reinforcement surface resulting of a protective layer formation. Thus, the inhibition efficiency was found to increase up-to 94.5% with decreasing corrosion rate up-to 0.57 × 10 Consequently, the most significant aspects of a construction material success are mechanical and durability of the concrete’s performance . In the globally ,5. 2 gas dissolved in water or from the atmosphere is reacting with free hydroxides, which are mainly made up of Ca(OH)2  in concrete, to develop calcium carbonate [2 gas also reacts with calcium–silicate–hydroxide gel in the concrete matrix thus further forming calcium carbonate [2 into the concrete, (ii) reaction of the CO2 with Ca(OH)2  in the presence of moisture, (iii) a reduction in pH from around 12.5 to 8.0 and (iv) de-passivation of the steel at this lowered pH.Amongst the most corrosive factors, concrete carbonation is one of the significant reasons that have a negative impact on the concrete’s durability. This process takes place when the COarbonate ,6. Besidarbonate . Since tTo control such defects, varied prevention strategies have been proposed, all aimed to stop, delay or slow down the corrosion mechanism including cathodic protection systems , stainleArtemisia pallens [Neolamarckia cadamba [Rhizophora apiculate [Musa paradisiac [Juglans regia [One of the renowned ways of controlling and reducing the corrosion rate of the low carbon steel is to apply organic inhibitors ,25,26,27 pallens , Neolama cadamba , Rhizophpiculate , Musa paradisiac , aloe veradisiac , apricotradisiac , Juglansns regia , Asafoetns regia  and Pomens regia . ResultsBambusa Arundinacea is applied onto contaminated concrete by sulfate and chloride. Loto et al. [Vernonia amygdalina (bitter leaf extract) with concentrations of 25–100% being applied onto steel reinforcement in concrete with exposure to 3.5% sodium chloride. The results have shown that the bitter leaf extract has fair corrosion inhibition concentrations of 50% and 75%. While the optimum inhibition efficiency of 90% was achieved when the inhibitor concentration examined is at its lowest at 25%. Meanwhile, the effect of another corrosion inhibitor, Vernonia amygdalina was studied by Eyu et al. [Vernonia amygdalina inhibitor is more effective compared to calcium or sodium nitrate in terms of reduction of corrosion rate for steel within concrete for the duration of the immersion. Another study by Okeniyi et al. [Anthocleista djalonensis leaf extract were incorporated into steel reinforced concrete exposed to the saline medium. They detected that the maximum inhibition efficiency of 97.43% was achieved at 0.4167% of a green inhibitor concentration. Our research team successfully reported the incorporation of 5% Elaeis guineensis/AgNPs into the reinforced concrete that found resulting in improving inhibition efficiency up to 95% [2O3, nano-TiO2, nano-Al2O3 and nano-SiO2 on mechanical properties. They concluded that the presence of 1.5% of nano-Al2O3, and nano-SiO2 indicated enhanced mechanical properties of concrete by up to 22% at 28 days in comparison with other nanoparticles. Moreover, several [Pertaining to the application of green inhibitor upon the reinforced concrete (RC), Abdulrahman and Ismail ,44 have o et al.  have alsu et al.  along wii et al.  was condp to 95% . This isp to 95%  investig several ,54,55,56Acacia senegal tree [2 environment. Further, morphology of steel reinforcement surfaces was screened via SEM and AFM and also the morphology of concrete specimens was examined by SEM, EDX, XRD and TGA. Finally, the powder of GA-NPs was characterized via transmission electron microscopy (TEM) to detect the particle size.In continuation of our earlier investigation, the present study reports Arabic gum-nanoparticles as corrosion inhibitors for reinforced steel in concrete that exposed over carbonated environment. Gum Arabic (GA) investigated was extracted in the form of exudate from the stem and branches of the trees, gal tree ,58. The gal tree ,60. As agal tree ,62. GA wgal tree ,64. Addigal tree . Furthergal tree ,67,68,69Acacia Senegal trees exuded was locally available and directly purchased from Alsaadi Company for Aromatics and spices, Basra, Iraq, was kindly provided by Dr. Mohammad Ali Asaad , and ground into powder. In order to obtain the fine size of extracted (nanoparticles), 1000 g of resultant powder was dissolved in 4000 mL distilled water for 24 h at ambient temperature (28 ± 2 °C). Afterward, the suspension was stirred for 3 h at 45 °C and then filtered using filtration paper (Whatman) grade 1 . Lastly, the resulting mixture was centrifuged  at 4500× g rpm for 30 min to achieve the GA-nanoparticles inhibitor. The characteristics of Acacia Senegal (gum Arabic) are listed in 5 (g/mol) and 0.35% respectively. The molecular structure of arabinogalactan is depicted in The dried Gum Arabic (GA) specimens were procured from The morphology (shape and size) of the GA-NPs powder was determined using BIO-TEM, model Hitachi-HT 7700, Tokyo, Japan. Distilled water was used to disperse the nanoparticles of the green GA inhibitor under ultrasonic treatment, and then a drop of the solution was placed onto the carbon-coated copper grids  and was investigated at 120 kV accelerated voltage.3 and fineness modulus of 2.57 was sieved by sieve  number of 4.57 mm and used as a fine aggregate. The crushed stone  had a minimum and maximum particle size as well as bulk density of 5 mm, 9.5 mm and 2700 kg/m3 respectively, was used as coarse aggregate. Normal fresh water in a w/c ratio of 0.55 and water content of 217 kg/m3 was used in all concrete mixtures.First phase, OPC—ordinary Portland cement (type I)  was prepared in accordance with ASTM C 150  as a conSecond phase, a concrete slab with dimensions of 200 mm (length), 180 mm (width) and 66 mm (thickness) was designed for corrosion examinations. Steel reinforcement bars  specimens of 225 mm in length and 16 mm diameter acting as a working electrode were cut by metal cutting machine  and then polished using different grades  of emery papers . Next, the steel bars specimens were degreased with concentrated acetone (70%) , washed in distilled water, air-dried and then embedded in the middle of the concrete slab, thus a 25 mm of concrete cover was provided around the steel bar on both sides and from the base, in order to provide limited corrosion prevention for steel reinforcement.3 were also cast, which were further used to investigate the influence of green GA-NPs inhibitor on accelerated carbonation and carbonation depth. Finally, after one day of casting, all concrete specimens were demoulded, and then cured in fresh water at 25 °C and relative humidity of 75% ± 5% for 28-day prior to move to CO2 gas chamber . The compressive strength of concrete was designed for 30 MPa at 28 days using 1:1.73:2.8 concrete mix design.In the third phase, based on the mass of cement, GA-NPs (3%) were mixed with water and added into concrete mix components during the mixing process and then cast into desired moulds . The mix proportion of concrete specimens was indicated in OCP—open-circuit potential was stabilised for 30 min over perturbation of 10 mV , a frequency range of 1000–100 Hz. Next, ZSimpWin software 3.2 was utilised for fitting impedance data with several sets of equivalent circuit. Furthermore, the electrochemical impedance spectroscopy parameters were calculated by inserting the following data: the density and the equivalent weight of rebar specimens is 7.85 (g·cm−3), and 27.92 (g) respectively, while the area of exposure of steel reinforcement is 68.36 (cm2). In addition, the EIS test were carried out for steel reinforcing bars in concrete that subjected to CO2 gas environment for 28, 90 and 180-day in the absence and presence of 3% GA-NPs inhibitor. The charge transfer resistance (Rs) and double-layer capacitance (Cdl) data were obtained from the diameter of the semicircles of the Nyquist plot. Based on the charge transfer resistance (Rct) data, the inhibition efficiency (IE%) of reinforced concrete was calculated from the following formula [Electrochemical impedance spectroscopy (EIS)  was conducted in a three electrode cell comprising of saturated calomel (SCE), steel specimens and platinum wire as reference, working and counter electrodes respectively, while NaCl of 3.5%  was used as an electrolyte for EIS experiments. Every measurement was examined using an electrochemical workstation model VersaStat 3  at 25 ± 2 °C, following the E formula :(1)IE%=. Afterward, the steel specimens extracted from the slabs and cleaned using cleaning solution in accordance with ASTM G1 [i and Wo are the weight loss values of reinforcement bar in the presence and in the absence and GA-NPs.−3), t is the time of exposure (h) and A is the rebar surface area (cm2).Gravimetric or weight loss measurements was carried out to determine the corrosion rate and inhibitor efficiency of concrete slabs exposed to CO ASTM G1 , which i ASTM G1 :(2)IE%=(The term “surface coverage (2) gas  for a period of 30 min, conducting this two times each day at a temperature of 25–30 °C. A pressure gauge was affixed to the carbon dioxide gas cylinder to observe the pressure inside the chamber. Next, the chamber was tightly closed and vacuumed for 2 min under a pressure of around 600 mmHg. Then, CO2 gas was allowed to pass to the chamber at a pressure of 750 Psi. A regulator  was affixed to the CO2 gas cylinder to control the pressure of CO2 inside the chamber. The specimens were subjected to this treatment for 28, 90 and 180 days. Once the carbon dioxide exposure had been completed, three specimens of untreated and treated concrete with GA inhibitor were subjected to splitting at 28, 90 and 180 days and their centres were sprayed with phenolphthalein solution to evaluate carbonation. Here, carbonation depth was identified as being the length of space between the coloured area’s edge and the outer surface of the concrete, the indicator of carbonation depth serves as a useful marker of the degradation that the specimens have incurred from carbonation attacks [After 28-day of curing the specimens in normal water, all the concrete cube specimens were removed and placed in the chamber. In line with the recommendations outlined by Sawada et al. , concret attacks . Whereas attacks . A 1% so2. The concrete specimens were drilled from the external to the internal surfaces, and 1 g of powder at each different depth was collected. Next, the collected powder was added to 50 mL of distilled water as a solvent and the entire mixture was stirred for 24 h at 25 °C. A pH meter  was used to calibrate the pH value of specimens exposed to carbon dioxide at different depths.The alkalinity variation of carbonated concrete specimens was evaluated by calibrating the pH value of concrete powder at depths of 2–20 mm at 180-day of exposure to CO2, the concrete slabs were split and the embedded carbon steel bars were carefully removed, rinsed in distilled water, air-dried, cut into small pieces with 16 mm in diameter and 10 mm thickness, and then used for morphologies scanned.The surface morphology of steel reinforcement specimens in the absence and presence of 3% GA-NPs was carried out using SEM-scanning electron microscope model Jeol, JSM-IT300, Tokyo, Japan, and atomic force microscope (AFM) model Nano-Wizard 3, Tokyo, Japan. Following 180 days of exposure to CO2 gas, concrete specimens were broken and small pieces of dimensions 10 × 10 × 7 mm were extracted from the core of specimens and then ground into powder. The powder specimens in the presence and absence of GA-NPs inhibitor were subjected to TGA/DTA thermograms analyser model TGA–Q 500, Cincinnati, OH, USA in order to detect the percentage of weight loss during the thermal degradation. Next, concrete powder of 2 g was placed in a ceramic pan having a height and diameter of 5 and 6 mm, respectively, and then subjected to heating at a temperature of 30–1000 °C. The decomposition of Ca(OH)2 concentrates was observed at temperature range of 400 to 500 °C and the C-S-H dehydration was also resulted in the weight loss at temperature range of 600–700 °C [2 and calcium hydroxide Ca(OH)2 content in the concrete matrix were determined according to the following formula [CH represents the dehydration of Ca(OH)2 at a temperature of 400–550 °C, and LOICC represents the loss of CO2 at a temperature of 600–750 °C range. According to Singh et al. [H and MWCH represent the molecular weights of water (18 g/mol) and CH (74 g/mol), respectively, while WLCH represents the weight loss of CH dehydration.Following 180 days of exposure to CO0–700 °C ,79. In ah et al.  the amou2. Small pieces of crushed carbonated concrete having a dimension of 14 mm × 14 mm × 5 mm were collected from the core of concrete cubes after subject them to split. Then, the specimens were transferred to vacuum environment up to 50 °C, till the constant mass of specimens was observed. Finally, the specimens were placed on cylinder stub and subjected to an automated platinum sputter coater (Model-Quorum (Q150R), Henan, China) for 1.5 min prior to testing.SEM  equipped with EDX-energy dispersive spectroscopy, was utilised to examine the morphology of concrete specimens with and without GA-NPs inhibitor after 180-day of exposure to COα source.The XRD pattern for concrete specimens treated and untreated with GA-NPs inhibitor was measured using model Rigaku, SmartLab 3 kW, Tokyo, Japan. The specimens were collected and ground into powder using a grinding machine . The powder was located on the sample holder, run at (30 mA/40 kV), scanned at 2-theta angle from 20–80° by scanning rate of 5°/min, and X-rays of (k = 1.5406 Å) created by a Cu K−3 mm/year) were obtained for the control specimen. These results indicate that CO2 penetrated the concrete cover and reached the streel reinforcement surface. Hence, destroyed the passive film and initiated of corrosion process. By contrast, the minimum weight loss value (0.0393 g), minimum corrosion rate (0.57 × 10−3 mm/year), and maximum end-of-test inhibitor efficiency (94.2%) were obtained for the specimen treated with 3% GA-NPs inhibitor. The observed increase in efficiency (%) with exposure time is attributed to the increasing surface coverage (θ) by adsorbed inhibitor molecules over the steel reinforcement bar to form a corrosion resistant layer during the exposure period [As a consequence of these reactions, the alkalinity (pH) of the concrete is lowered, which is led to producing voluminous rust over steel reinforcement. This can impact the reduction in the thickness of the steel reinforcement, and general degradation , hence, e period . Thus, t2. According to literature [dl) and charge-transfer resistance (Rct). However, the semi-circle loops that appeared in the high-frequency region demonstrated the function of the charge transfer process in controlling the electrode reaction, while the presence of a large depressed semicircle (depressed capacitive loops) of modified steel reinforcement with GA-NPs that exposed to CO2 for 180 days extending from the high to low-frequency regions, indicating that the primary effect of the charge-transfer resistance on the corrosion reaction results from the development of a protective film due to the adsorption of inhibitor molecules onto the steel surface. Besides, the depressed nature of the semicircles is usually related to the roughness and inhomogeneity of the solid surface.Nyquist plots  representerature ,84,85, ts) represents the ohmic resistance of the system, and resistor (Rct) represents the resistance of the inhibitor to the charge transfer process during metal oxidation, whereas (Q) is introduced as the double layer capacitance (Cdl). In fact, various equivalent circuits were generated and fitted against the experimental impedance values, while the circuit that having lowest fitting error was selected and reported here.dl-double layer capacitance and enhances the Rct-charge transfer resistance, so that a great diameter semicircle is detected in the Nyquist plots, while the ability of GA-NPs corrosion inhibitor to adsorb upon the electrode surface may explain the observed decrease in Cdl.The precise examination of the impedance parameters at 28, 90 and 180 days are presented in ct values with time from 20,400 to 49,600 Ω·cm2 (2 layer which is led to the reduction of concrete permeability and the diffusion of carbon dioxide due to the development of C-(A)-S-H gel [The observed increase in R00 Ω·cm2  followin-S-H gel , and by -S-H gel . Adsorpt-S-H gel . After t-S-H gel .dl (0.0138 × 10−5 μF·cm−2) were obtained in the presence of GA-NPs inhibitor after 180 days of exposure. These results may be explained by the hydrophobic capacitive nature of γ-Fe2O3 film that established upon the surface of reinforcing steel, which gives a huge time constant indicating passivation of the steel. This can be compared with increased the Cdl of (7.68 × 10−5 μF·cm−2) for control specimens at the end of test due to diffusion of CO2 in concrete. The regions of continuously increasing real and imaginary impedance  carbonate-FeCO3 due to the diffusion of CO2. Conversely, the image of steel reinforcement surface  is associated with smaller carbonation depths when 3% GA-NPs inhibitor is present and when compared to control specimen. 2 gas for 28, 90 and 180 days with and without GA-NPs inhibitor. The carbonation depths of control specimens were measured as 4.1 mm, 19.6 mm and 34.4 mm at 7, 28 and 180 days of exposure, respectively, while 3.0, 6.2 and 12.3 mm carbonation depths were recorded for modified concrete specimens with GA-NPs inhibitor at the same period of exposure. This implies that the GA-NPs inhibitor is linked to the clearest impact to enhance the concrete matrix which led to lowering carbonation depth by 64.42% following 180 days of exposure to CO2 gas with respect to control specimens. Moreover, the high carbonation depth of control specimens is not surprising. The reason is that control concrete is inclusive of numerous internal pores especially with a high w/c ratio (0.55), and this means that it can be subjected to carbonization is a clearer way. Kim et al. [m et al.  observedm et al. ,95,96, t2 in the concrete during the hydration process and development of further C-S-H gel. Moreover, the aggregate structure can be also enhanced in the presence of nanoparticles, resulting in a strong bond between cement paste and aggregates.According to Valcuende and Parra , the con3. In another meaning, during the carbonation process, the content of Ca2+ ions in the pore solution becomes reduced. This, in turn, triggers dissolution of calcium hydroxide and diffusion of Ca2+ from the interior of the concrete to the site of carbonation, where the concentration of both components will be at a minimum due to the low solubility of calcium carbonate. Moreover, following long-term degradation, the cementitious materials of the concrete pore to the surface of the specimens was nearly free of calcium. This leads to a reduction in the alkalinity of the pore solution and may lead to decomposition of the hydration products which, in turn, generally leads to increased porosity of cement-based materials. This increased porosity due to leaching, along with the lowered pH values, can enhance the rate of ingress of aggressive substances or the rate of corrosion of reinforcing steel. The chemical reactions of carbonation process may explained as follows [The pH values of concrete specimens exposed to carbonation for 180 days in the absence and presence of GA-NPs inhibitor at a variety of depths are depicted in  follows :(13)CO2+In the pore solution, the 2.As a result of the above reaction, the concentration of calcium ions reduced and dissolution of essentially Ca(OH)2 and CaCO3 respectively until the Ca(OH)2 is totally consumed.This leads to dissolved and precipitation of Ca(OH)Conversely, the carbonation effect on GA-NPs specimens was negligible, since the pH remains as high as 12.5 at a depth of 18 mm  which is2 gas for 180 days. These analyses indicate three characteristic temperature ranges in which weight loss occurs during heating. From 2, while the weight loss of the third region at 600–750 ℃ is assigned to decomposition of amorphous calcium carbonate (CaCO3) and crystalline. The dehydrogenation of Ca(OH)2 can be briefly described as follow; the amount of the molecules of water are rapidly reduced in the dehydration process, with not much change in the amounts of hydroxyl. However, when the degree of hydration is decreased to half, just a small quantity of water has remained in the C-S-H matrix. Additional reduction of hydration degree can occur by the decreasing of Ca-OH and Si-OH groups “dehydroxylation stage”. Thereafter, a single molecule of H2O separates and awards a single of its own H atoms to the deprotonated Silanol, as a result, the development of double hydroxyls, Ca-OH and Si-OH. Moreover, in the presence of deprotonated hydroxyl groups, the H2O atoms are thermodynamically unsteady. Hence, the dehydroxylation of calcium–silicate–hydroxide takes place.2 for 180 days. The calcium hydroxide content of GA-NPs specimens was decreased significantly from 10.20% to 3.72% in comparison to the specimen without GA-NPs. The presence of the lesser weight-loss values of treated concrete with GA-NPs inhibitor at a temperature range of 400 to 550 ℃ proposed that the consumption of Ca(OH)2 (portlandite) resulted from the significant pozzolanic activity of GA-NPs concrete and formation of extra C-S-H gel (9.72%). The improvements of portlandite consumption and formation of C-S-H gel were 63.53% and 67.63% respectively, with respect to control concrete. Nevertheless, it should also be noted that the particularly high amounts of portlandite in control concrete (10.20%) which was determined at the same temperature, can be resulted due to the susceptibility of the concrete to high carbon dioxide gas because of the porous nature of the concrete. Moreover, the modified concrete specimen with GA-NPs has displayed a decrease in the mass loss at a temperature range of 600 to 800 ℃, which is strongly confirmed that the incorporation of green GA-NPs inhibitor made the concrete denser, less porous and less permeable to diffuse the CO2 gas, thus, enhanced the durability of concrete.2 attack are observed on the surface of the control specimen. According to Ekolu [2 into the concrete lowers the pH to around 9–10, leading to breakdown of the natural protective passive layer, so that corrosion begins to occur. The CH  and (C-S-H) both react with CO2 to form poorly soluble calcite, which precipitates within the pore space, affecting the properties of the concrete and increasing the corrosion rate of the embedded steel.Following 180 days of exposure to accelerated carbonation conditions, the SEM morphologies of the control specimen and the specimen treated with green GA-NPs inhibitor were as presented in to Ekolu , diffusiIn contrast, 2 gas into the concrete surface reduces both the pH value and the concentration of Ca2+ ions, leading to dissolution of the calcium–silicate–hydroxide gel due to consumption of CH. Decomposition of monosulfate and ettringite occur respectively at pH 11.6 and 10.6, after which most of the Ca2+ ions from the C-S-H gel bind to CaCO3 leaving just a minor amount of Ca2+ ions in the silica gel. Hussain et al. [n et al.  attributn et al.  pointed 2 gas, are presented in 2.The X-ray powder diffraction (XRD) results for the control concrete specimen and the specimens treated with green GA-NPs inhibitor, following 180-day of exposure to CO−3 mm/year respectively, by increasing the surface coverage area led to increasing the adsorption of inhibitor molecules on steel reinforcement. In addition, the results of EIS revealed that the double-layer capacitance of steel reinforcement was decreased while the charge transfer resistance was increased in the presence of inhibitor due to the formation of a protective layer.The results of weight loss and EIS evidenced that the incorporation the GA-NPs inhibitor into concrete increased the inhibition efficacy and decreased the corrosion rate up to 94.5% and 0.57 × 10The morphology of steel reinforcement by SEM and AFM studies confirmed the formation of a protective layer. In addition, AFM images of rebar in the presence of GA-NPs inhibitor confirmed low surface roughness which is strongly promoted the ability of the inhibitor to adsorb over rebar.2.The carbonation depth tends to increase with increased time of accelerated curing. Nevertheless, the lowest level of carbonation was clearly observed for the specimen modified with GA-NPs, indicating that the tiny scale of green inhibitor molecules, which was 40.24 nm according to TEM, can block the capillary pores of concrete to form an impermeable barrier against the ingress of COThe best linear relationship was observed for the concrete modified with 3% GA-NPs inhibitor, with a correlation coefficient of 0.9093, compared to a minimum value of 0.7877 for the control specimen.2 gas by dropping the pH value to 10.4 at depth of 20 mm. In contrast, the high surface area of nanoparticles was capable to fill the porous of concrete, which led to enhancing the pozzolanic reaction and formation of extra C-S-H gel, hence, the pH value of modified concrete was raised to 12.5 at a depth of 20 mm.The alkalinity of control specimens was reduced after 180 days of exposure to COFinally, the microstructural morphologies of concrete specimens in the presence of GA-NPs inhibitor including TGA/DTA, SEM-EDX and XRD confirmed the ability of green GA-NPs inhibitor to increase the durability of concrete by reducing the ratio of Ca/Si to 0.69, consumption of portlandite, and increased the peaks of quartz, thus the development of extra C-S-H gel.The impact of the developed green gum Arabic inhibitor upon the behaviour of reinforced concrete exposed to carbonation for 180 days was investigated. The conclusions are set out according to the results of various tests as follows:


Traditional, complementary, alternative and integrative medicine (TCAIM) can be described as diverse medical and healthcare interventions, practices, products, or disciplines that are not considered as part of conventional medicine. Inherent in its definition, TCAIMs are comprised of a wide variety of therapies with highly variable safety and effectiveness evidence profiles. Despite this, the use of many TCAIMs is highly prevalent among patients globally. The present study consists of a bibliometric analysis of TCAIM journals.A single search of all International Standard Serial Number (ISSNs) of all journals categorized as “complementary and alternative medicine” (code 2707) based on the All Science Journal Classification (ASJC) was run on Scopus on April 17, 2021. All publication types were included; no further search limits were applied. The following bibliometric data were collected: number of publications , authors and journals; open access status; journals publishing the highest volume of literature and their impact factors; language, countries, institutional affiliations, and funding sponsors of publications; most productive authors; and highest-cited publications. Trends associated with this subset of publications were identified and presented. Bibliometric indicators of production were calculated, and bibliometric networks were constructed and visualized using the software tool VOSviewer.n = 15,144). The most productive countries included China , the United States , and Germany ; a number of the most common institutional affiliations and funding sponsors also originated from these three countries.A total of 172,466 publications , were published by 219,680 authors in 143 journals from 1938 to 2021. Since the 1940s, an upward trend with respect to the volume of publications can be observed, with a steep increase observed between the mid-2000s and mid-2010s. The journal that published the largest number of publications was the Journal of Natural Products (The number of publications collectively published in TCAIM journals follows an upward trend. Given a high prevalence of TCAIM use among patients, increased acceptance of TCAIM among conventional healthcare providers, and growing interest in the research of TCAIM, future work should continue to investigate and track changes in the publication characteristics of the emerging research on this topic. T2-T1 represents the unit difference between the initial time and the final time. Doubling time is defined as the amount of time required for the subject matter to double its production. The doubling time was calculated based on the following equation: [DT = 0.693/Relative Growth Rate]. Price’s law was also applied to the subset of publications analysed [Relative growth rates and doubling times were calculated for publications published between 1938 and 2020. The relative growth rate represents the increase in the number of publications published per unit of time. The relative growth rate was calculated based on the following equation: [analysed . This lan = 15,144) published the largest number of publications indexed in Scopus, followed by Zhongguo Zhongyao Zazhi , and Planta Medica . All journals included within this bibliometric analysis were hand-searched on InCites Journal Citation Reports [A total of 172,466 publications , were published by 219,680 unique authors in 143 journals from 1938 to 2021. Since the 1940s, an upward trend with respect to the volume of publications can be observed, with a steep increase observed between the mid-2000s and mid-2010s. This upward trend has continued with 2020 marking the year with the highest number of publications to date. The Journal of Natural Products , followed by pharmacology, toxicology and pharmaceutics , then biochemistry, genetics and molecular biology . Publications were primarily published in English , followed by Chinese , then German (n = 8611). The most common document types were article  and review ; articles primarily include original research, while reviews include literature, scoping, and systematic reviews. The most productive countries included China , the United States , and Germany . The most common affiliations were the China Academy of Chinese Medical Sciences (n = 3560), the Beijing University of Chinese Medicine (n = 2896), and the Chinese Academy of Sciences (n = 2896); the most common funding sponsors were the National Natural Science Foundation of China (n = 5711), the National Institutes of Health (n = 4055), and the US Department of Health and Human Services (n = 4032). The general characteristics of eligible publications are summarized in Table The subject area containing the largest number of publications was medicine , as shown in this figure, resulted in a correlation coefficient r = 0.9698, which indicates that 5.94% of variability remains unexplained by this adjustment. In contrast, the linear adjustment (y = 97.915x - 1971.9) of the measured values provides an r = 0.8160, and thus an unexplained variability of 33.42%. These results suggest fulfilment of Price’s Law, with scientific production within CAIM journals showing exponential growth. Additionally, the relative growth rate was found to range from 0.05 to 0.67. Doubling time was found to range from 1.04 to 15.02. Table Figure Bibliometric networks were constructed and visualized using the software tool VOSviewer, and include all 172,466 captured by the present study’s search. This added layer of analysis of the most influential subset of publications captured provides a greater understanding of the relationship that exists between certain items . In each bibliometric network (figure), each item is represented in a network visualisation by a label and a circle; the weight of an item determines the size of the label and the circle of an item. Figure The objective of the present bibliometric analysis is to capture the characteristics of the research literature published in TCAIM journals. The search conducted on Scopus yielded over 170,000 publications, representing the largest bibliometric analysis of TCAIM literature to date to the author’s knowledge. Since the 1940s, an upward trend with respect to the volume of publications can be observed, with a steep increase observed between the mid-2000s and mid-2010s. This upward trend has continued with 2020 marking the most productive year globally to date. Unsurprisingly, therefore, the production in this body of literature follows Price’s law of exponential growth, which is characteristic of fields of research which have experienced great and continued advances and interest from the international research community; other bodies of research literature that have experienced exponential growth include the topics of medical informatics , glaucomIn interpreting these results, the reader should be aware of a number of caveats. For example, authors who have spent more years working in research, and journals that have been publishing for a longer period of time and/or have a greater proportion of their archive indexed in Scopus, will have more publications, citations, and collaborations. Additionally, older publications will have an increased chance of receiving citations, as evidenced by only 15 of the most 100 cited articles being published since 2020. Additionally, it is worthwhile to note that while only the journal’s impact factor was reported in Table The findings from published bibliometric analyses specific to the TCAIM research literature can be compared to that of the present study. One of the first bibliometric analyses of the TCAIM research literature was published by Barnes et al. in 1999 . Using aIn line with the findings made by Barnes et al. (1999) , Danell Beyond the aforementioned comparative literature, it is worth noting that it has been far more common for bibliometric analyses to be conducted on a specific TCAIM-related topic. These have included acupuncture –56, aromThis present bibliometric study captured and analysed the characteristics of over 170,000 publications, making it the largest conducted to date with respect to the TCAIM literature, and the most comprehensive with regards to TCAIM journal inclusion. Searches were conducted on Scopus as this academic database has a larger coverage in comparison to other databases such as Web of Science. Despite this, it must be acknowledged that all academic databases contain gaps in their indexing, and this was realized at the point of analysis in the present study. Publication data collected from Scopus was not externally verified against another source, and it is also important to note that the number of publications reflect what was indexed by the database as of the search date, and not necessarily the true number of publications published by the included journals themselves. It should be noted that publications included in this bibliometric analysis were based on the fact that they were published in a journal belonging to the “complementary and alternative medicine” category code 2707), identified based on the ASJC provided by Scopus; as evidenced by Table 707, idenThe present study provides current insight into the characteristics of publications published across TCAIM journals, and represents the largest bibliometric analysis conducted to date with respect to the TCAIM literature. The most productive countries included China, the United States, and Germany; unsurprisingly, a large proportion of common institutional affiliations and funding sponsors associated with this subset of publications also originated from these countries. The volume of publications has increased steadily since the 1940s, and a steep increase was observed between the mid-2000s and mid-2010s, which is largely attributable to increased available funding for TCAIM research globally. This upward trend has continued with 2020 marking the year with the most publications to date. Beyond identifying the large diversity of TCAIMs studied, this study also highlights therapies which may be understudied and warrant further investigation. Given a high prevalence of TCAIM use among patients, increased acceptance of TCAIM among conventional healthcare providers, and growing interest in the research of TCAIM, future work should continue to investigate and track changes in the publication characteristics of the emerging research on this topic. The creation of an operational definition of TCAIM informed by a systematic search strategy, followed by the development of standardized search strategies for major academic databases based on this operational definition, may serve to achieve these goals more comprehensively.