The microstructure evolution and corresponding mechanism during deformation were studied in-depth, using electron backscattering diffraction, transmission electron microscopy and precession electron diffraction. During deformation, dynamic recrystallization (DRX) occurred, along with extensive dynamic recovery, and the active DRX mechanism depended on deformation conditions. At higher Zener-Hollomon parameter (Z ≥ 5.93 × 1027 s−1), the development of the shear band was promoted, and then continuous DRX was induced by the formation and intersection shear band. At lower Zener-Hollomon parameter (Z ≤ 3.10 × 1025 s−1), the nucleation of the new grain was attributed to the combination of continuous DRX by uniform increase in misorientation between subgrains and discontinuous DRX by grain boundary bulging, and with increasing temperature, the effect of the former became weaker, whereas the effect of the latter became stronger. The DRX grain size increased with the temperature. For alleviating ridging, it seems advantageous to activate the continuous DRX induced by shear band through hot deformation with higher Z. In addition, the modified Johnson-Cook and Arrhenius-type models by conventional way were developed, and the modified Johnson-Cook model was developed, using the proposed way, by considering strain dependency of the material parameters. The Arrhenius-type model was also modified by using the proposed way, through distinguishing stress levels for acquiring partial parameter and through employing peak stress to determine the activation energy and considering strain dependency of only other parameters for compensating strain. According to our comparative analyses, the modified Arrhenius-type model by the proposed approach, which is suggested to model hot-deformation behavior for metals having only ferrite, could offer a more accurate prediction of flow behavior as compared to other developed models.The deformation behavior for highly purified Fe-17Cr alloy was investigated at 700~1000 °C and 0.5~10 s Fe-Cr alloy steels are finding wide applications and replacing some Cr-Ni austenitic steels because of their excellent stress corrosion cracking resistance; high thermal conductivity; and low expansion coefficient and cost ,2. Howevr-value and weaken the occurrence of ridging by enhancing grain fragmentation and grain interior nucleation and refining hot-rolled and annealed microstructure. Dynamic recrystallization (DRX) holds great promise for controlling and refining the microstructure and thereby improving the r-value and alleviating ridging [Improving these shortcomings for Fe-Cr alloys has been attempted by controlling rolling process ,6,7,8,9. ridging ,11,12. TMany efforts have been focused on understanding flow behavior and/or microstructure evolution of the Fe-Cr alloys with high stacking fault energy (SFE) ,18,19,20α (≈β/n′) is usually acquired through utilizing all experimental results for obtaining n′ in Equation (7), which is invalid for the experimental results with higher stress, and β in Equation (8), which is not suitable for the experimental results with lower stress, as described in in Equations (6)–(8) in B5, λ1 and λ2 (as stated in Equation (2) in this study) are all considered to be constants. As a matter of fact, according to studies about the establishment of JC model [In addition, regarding the flow behavior and constitutive models of Fe-Cr alloys, a majority of constitutive equations have been developed based on the flow behavior during hot deformation at elevated temperatures above 900 °C ,17,18. OJC model ,30,31,32In this study, the deformation behavior of a highly purified Fe-17Cr alloy was investigated at temperature with a wide range which covers the practical deformation conditions during the warm-rolling process. The corresponding dynamic microstructure was analyzed in-depth, using electron backscatter diffraction (EBSD), transmission electron microscopy (TEM) and precession electron diffraction (PED). The constitutive description on the basis of the above models was constructed through utilizing conventional way and new way for solving the existing issues, and their performance was comparatively analyzed in detail and consequently a most suitable way was worked out. Moreover, the microstructure evolution was studied, and the corresponding mechanism was explored during deformation, with an objective to provide a theoretical basis for the basic research of microstructure–property relationships and the optimization of rolling process, especially the warm-rolling process.−1 heating rate and then held at this temperature for 180 s to homogenize temperature. They were then cooled to 700, 750, 800, 850, 900, 950 and 1000 °C at the 10 °C·s−1 cooling rate and held at corresponding temperatures for 30 s to form the uniform distribution of temperature. Then these samples were deformed at the 0.5, 1, 5 and 10 s−1 strain rates with the 0.55 strain. Tantalum foils and high-temperature lubricant (MoS2) were employed to minimize the friction coefficient during isothermal hot-compression tests, ensuring the reliability of measured data. The microstructure analyses were carried out by applying EBSD, TEM and PED, and the samples were prepared by applying the methods reported in Reference [The cast ingot of a highly purified Fe-17Cr alloy  was hot-rolled to band with the thickness of 12 mm in the temperature range of 1100 to 900 °C after treating at 1150 °C for 1 h. Using a MMS 300 thermo-mechanical simulator , the isothermal hot compression test was carried out by using the cylindrical sample (Φ8 mm × 15 mm) according to the deformation processes . Note theference .m, which can be evaluated by the slope in m decreases and the effect of strain rate on flow stress becomes weaker. This can be explained in term of the stacking fault energy. A similar sensitivity of the effect of strain rate on flow stress to deformation temperature has been observed and proved in other stainless steels [All the flow curves under different processes possess similar characteristics  that are fitting . With deecreases , indicats steels ,36.−1. Overall, the actual temperature change is an extremely complicated subject during deformation, especially at high rate, and its effect on flow stress becomes overwhelmingly difficult to estimate correctly. Despite that, the numerical evaluation of the actual temperature rise is often simplified by only using the Taylor–Quinney coefficient as a constant value, which can lead to distinct overestimation of the adiabatic heating [−1) is not considered during constitutive modeling.It is well-known that high strain rates may cause adiabatic heating in the specimens. The adiabatic temperature increase can be estimated from the flow curves employing the Taylor–Quinney coefficient which reflects the ratio of plastic work transformed into heat or stored energy. However, this coefficient is inconstant during deformation and its value is dependent of not only the amount of strain, but also the loading mode, strain rate and temperature at which the strain was achieved . It was  heating . Therefoσ, ε, T, rT, mT, A2, n1, A3, n2 and A1 are identical to those reported in Reference [λ1, λ2, B1, B2, B3, B4 and B5 are parameters. This model has been utilized to predict flow behavior of some steels [The JC model describing the flow behavior of metals can be expressed as follows :(1)σ=A1+eference . Clearlyeference  revised e steels ,30 and ae steels ,41. Notee steels , so the e steels ,30.B1, B2, B3, B4, B5, λ1 and λ2 at reference conditions of 700 °C and 0.5 s−1 are acquired to be 144 MPa, 920 MPa, −2497 MPa, 2266 MPa, 0.011, −0.00348 and 0.00029 by linear fitting, respectively, as shown in AAREs) under different reference conditions B1, B2, B3 and B4Determination of material parameters B1, B2, B3 and B4 are 103, 439, −1171 and 1019 MPa at the reference condition of 850 °C and 1 s−1 according to Obviously, the (2)B5, λ1 and λ2Determination of strain-dependent material parameters B5, λ1 and λ2 at the strain of 0.3 are acquired to be 0.060, −0.00349 and 0.00021 by linear fitting, respectively ε˙=Aseference . In addion below :(9)Z=ε˙⋅Q, α, A and n as polynomial function of strain. Moreover, n′ and β are determined the through use of all measured stresses, and then α (≈β/n′) is determined. In this section, this conventional approach is employed for developing modified Arrhenius-type model.In this model, the effect of strain on flow stress has not been considered. As stated in n′, β, α, Q, n and lnA at the strain of 0.3 are acquired to be 22.47, 0.12 MPa−1, 0.0053 MPa−1, 471,332.541 J·mol−1, 11.0 and 51.4 by linear fitting, respectively, as shown in n′, β, α, Q, lnA and n for other strains are calculated, and the strain-dependent parameters α, Q, n and lnA are perfectly suited to be expressed by 6th-order polynomial fitting, as shown in The Finally, the modified Arrhenius-type model by conventional approach for the compensation of strain and the determination of key material parameter is shown by using the equation below:Q and α is suggested through utilizing the characteristic stress, peak stress σp, which does not suffer from the differences in the microstructure characteristic at different deformation conditions, and the determination of A and n are suggested through considering them as polynomial functions of strain. This section employs this method, compensating the strain.However, two important problems are usually neglected by the abovementioned conventional approach. One problem is that, through utilizing the flow stress obtained according to the different microstructure characteristic , the parameters  at a certain strain are obtained, because, at a given strain and different temperatures and strain rates, flow curves may be in different stages of deformation, and samples may take different deformations or softening mechanisms, leading to the formation of different microstructure characteristic and corresponding flow stresses. It is well-known that nearly the same deformation or softening stages can be represented by the characteristic stresses, such as peak stress at different deformation conditions. To solve the above issue, the determination of α (≈β/n′) is usually acquired through utilizing all experimental results for obtaining n′ in Equation (7), which is invalid for the experimental results with higher stress, and β in Equation (8), which is not suitable for the experimental results with lower stress. To solve the above issue, distinguishing experimental results is suggested according to the flow-stress levels, and the determination of n′ and β is suggested through employing experimental results with low flow stresses and high flow stresses, respectively. This section employs this method, acquiring crucial parameter α.Another problem is that the α and Q. Based on deformation behavior of other Fe-Cr alloys reported by researchers [α of the Fe-17Cr alloy is initially estimated as 0.009 MPa−1 for judging high peak stress and low peak stress and subsequently calculating n′ and β. In this case, the n′ is obtained by using the peak stresses during deformation at the conditions of 1000 °C and 0.5–10 s−1, and β is calculated by using the peak stresses during deformation at the conditions of 700–850 °C and 0.5–10 s−1. The n′, β, α and Q are acquired to be 12.68, 0.14 MPa−1, 0.0110 MPa−1 and 550,059.9 J·mol−1 by linear fitting, as shown in Firstly, by utilizing peak stresses, we calculate the parameters earchers ,16,17, tA and n are considered as the strain-dependent parameters. The lnA and n at the strain of 0.3 are acquired to be 50.3 and 8.3 by linear fitting, respectively, and those for other strains are also obtained, and the strain-dependent parameters n and lnA are perfectly suited to be expressed by 6th-order polynomial fitting, as shown in Secondly, the parameters −1; 700 °C and 10 s−1), the predicted values based on the constitutive descriptions in this study, especially the modified Arrhenius-type model by the proposed approach, can track the experimental data very well. The factors that generate the abovementioned deviations are as follows:(1)The deviations in the measurement of flow stress;(2)The deviations from data fitting for determining the parameters such as liner fitting;(3)The limitation of the phenomenological constitutive model ,44,45,46(4)−1). This has a weak effect on the relationships between flow stress and deformation conditions and the determination of material parameters; that is to say, only a small part of thermal softening effect can be considered during the constitutive modeling. Therefore, the flow stresses predicted by the developed constitutive models are still overestimated at some deformation conditions; however, the experimental data affected by thermal softening were also used for the constitutive modeling. The combined effect of abovementioned factors (1)–(4) results in the deviations, so these deviations are not evenly distributed around the experimental curve.The adiabatic temperature rises during high rate-deformation heating . It shouFor evaluating the constitutive descriptions, the predicted flow stresses are compared with the experimental data, as shown in R) and average absolute relative error (AARE) are employed. The R is shown in the equation below:M, P, N are identical to those reported in Reference [AARE for the modified Arrhenius-type models by the proposed approach is also lower as compared to the other three developed constitutive models, as shown in −1 with the 0.55 strain are carried out, and the comparison between the measured flow curves and predicted flow stresses at this deformation conditions is displayed in In order to quantitatively evaluate the developed constitutive models, the correlation coefficient  for establishing the relationship between microstructure evolution and deformation conditions. The microstructure analyses are the powerful tool to further elucidate the dynamic softening mechanism, understand the microstructure evolution during deformation and hence optimize rolling process and improve formability and surface quality of Fe-Cr alloys. In order to elucidate the microstructure evolution and dynamic softening mechanism in-depth, the dynamic microstructures at different deformation conditions were systematically analyzed by using EBSD or/and TEM. The activation energy −2) and Nickel (128 mJ·m−2), Fe-Cr alloy or ferritic stainless steel also possesses high SFE [The SFE of steels were usually determined by the following methods ,50,51,52high SFE , which iZ-deformation conditions, all the DRX grains can be randomly formed along the original HAGBs and in the grain interiors. The number of new grains formed along the original HAGBs increases and that nucleated in the grain interiors decreases, and the DRX grain size increases, as the temperature rises  can be expressed as follows [P is net pressure on the grain boundary; M is the boundary mobility related to temperature (T) by following an Arrhenius-type of relationship, M = M0exp(−Qa/RT); Qa is the apparent activation energy. Increasing temperature can accelerate grain boundary migration and then the DRX grain formation. Therefore, the number of DRX grains randomly formed at the original HAGBs increases as the temperature rise . During deformation, the appearance of more family of shear bands and higher density of shear bands indicates the activation of multiple shearing. An operation of multiple shearing is a beneficial condition for generating strain-induced (sub)grain boundaries and dynamic recrystallization during deformation .Z, the dislocation, in-grain substructure and misorientation distribution of grain boundaries in the deformed grain interiors were analyzed, as shown in In order to explore the nucleation of new fine grain during deformation with higher With the further increase of strain in some localized regions, the misorientations of subgrain boundaries rapidly increase, leading to the formation of some strain-induced HAGBs d. MeanwhThe misorientation distributions of grain boundaries in the interiors of original deformed grains having different shear hand families and density in Z. It is very difficult to measure the strain of each grain, but it can be qualitatively evaluated through Kernel average misorientation (KAM) according to the EBSD measurement. KAM can give evidence for the stored energy in the deformed microstructure, and high KAM values indicate the high stored energy and the large strain. Through EBSD analysis  CDRX induced by shear band occurs for the formation of new grains. At lower Z-deformation conditions (Z ≤ 3.10 ± 0.72 × 1025 s−1), the nucleation of new grain can be attributed to the combination of DDRX induced by grain boundary bulging and CDRX induced by a uniform increase in misorientation between subgrains. Moreover, according to the discussion in Z parameters for the occurrence of DRX is determined by the minimum deviations between the Z values of the activation of DRX and no DRX, based on the limited deformation conditions. In addition, the microstructure evolution may be applicable to other Fe-Cr alloys and ferritic stainless steels. The critical deformation conditions for the operation of DRX mechanism and the activation energy of hot deformation may be different due to the different chemical compositions between experimental steel and other materials, leading to the different critical Zener-Hollomon parameters for the occurrence of DRX mechanism. However, for other Fe-Cr alloys and ferritic stainless steels, the relationship between DRX mechanism and deformation condition is similar to that of experimental steel in this study. That is to say, the CDRX induced by shear band will be prone to occur at higher Z d-formation conditions, while at lower Z-deformation conditions, DDRX induced by grain boundary bulging and CDRX induced by uniform increase in misorientation will easily take place and with the increase of temperature, the effect of DDRX became stronger, whereas the effect of CDRX became weaker.Through the observation of microstructures above, the different DRX nucleation mechanisms activated during deformation are analyzed, as shown in The flow behavior and restoration mechanisms resulting in the dynamic microstructure evolution of highly purified Fe-17Cr alloy were investigated by using compression tests. The following conclusions can be drawn:(1) Deformation temperature and strain rate play a key role in flow stress, and increasing temperature and decreasing strain rate lead to decreasing flow stress. Deformation temperature has a significant effect on strain-rate sensitivity (stress-increasing tendency with the increase of strain rate), and as temperature lowers, strain-rate sensitivity reduces, which can be explained in terms of the stacking fault energy.Z-deformation conditions (Z ≥ 5.93 × 1027 s−1), lower strain-rate sensitivity could increase the probability of flow localization, thereby promoting the formation of in-grain shear band, and continuous dynamic recrystallization induced by shear band can be responsible for the formation of new grains. At lower Z-deformation conditions (Z ≤ 3.10 × 1025 s−1), the nucleation of new grain can be attributed to the combination of continuous dynamic recrystallization induced through a uniform increase in misorientation between subgrains and discontinuous dynamic recrystallization induced through grain boundary bulging.(2) During deformation, dynamic recrystallization occurs alongside extensive dynamic recovery, and the nucleation mechanisms of new grains can be considered as a function of deformation conditions. At higher Z-deformation conditions (Z ≤ 3.10 × 1025 s−1), there is a competition between continuous and discontinuous dynamic recrystallization mechanisms as a function of deformation temperature, and with the increase of temperature, the effect of discontinuous dynamic recrystallization induced by grain boundary bulging became stronger, whereas the effect of continuous dynamic recrystallization induced by the uniform increase in misorientation became weaker. Moreover, the DRX grain size increases with the deformation temperature.(3) At lower (4) The modified Arrhenius-type model was constructed by using the proposed approach through distinguishing stress levels for acquiring partial parameter, employing peak stress to determine the activation energy and considering strain dependency of only other parameters for compensating strain. The modified Johnson-Cook model, by considering strain dependency of the parameters, and the modified Johnson-Cook and Arrhenius-type models, by conventional approach, were also developed.(5) The modified Arrhenius-type models by the proposed approach can all offer a more accurate prediction of flow behavior under investigated strain rate–temperature domain as compared to the other three developed constitutive models in this study. The modified Arrhenius-type model by the proposed approach is recommended to describe the flow behavior for alloys and steels having only ferrite during deformation, especially at lower temperatures. In addition, for hindering the surface ridging of Fe-Cr alloys, it seems advantageous to activate the CDRX induced by shear band and form a considerable number of new fine grain nuclei through hot deformation with higher Z, because this is beneficial to enhancing grain fragmentation and grain interior nucleation during annealing, thereby weakening the inhomogeneous orientation distribution.


Rhodopseudomonas palustris converts nitrogen gas (N2) to fertilizer ammonia (NH3) and also produces clean energy hydrogen gas (H2) from protons (H+) when it is grown anaerobically in nitrogen fixing medium with illumination, a condition that promotes the expression of active nitrogenase. Compared with quantitative real-time PCR (qRT-PCR) and the lacZ reporter system, two methods commonly used for in vivo study of nitrogenase regulation in photosynthetic bacteria, the fluorescent protein reporter system has advantages in terms of its simplicity and sensitivity. However, little is known concerning if the fluorescent protein reporter system can be used in bacterial cells that need to grow anaerobically. Here, we developed an RFP-based method to measure the nitrogenase gene expression in photosynthetic bacteria grown anaerobically. This method was able to determine the levels of both the genome-based and the plasmid-based nitrogenase expression under anaerobic conditions, providing a better method for in vivo study of gene expression affected by oxygen. The RFP reporter system developed here will promote a better understanding of the molecular mechanism of nitrogenase regulation and will be used on other genes of interest in a wider range of anaerobic bacteria.The photosynthetic bacterium  Rhodopseudomonas palustris is a photosynthetic nitrogen-fixing bacterium widely distributed in nature [2) to ammonia (NH3) by nitrogenase as a major source of bioavailable nitrogen. Moreover, the conversion of N2 to NH3 by nitrogenase is accompanied by the production of hydrogen gas (H2), which can be used as clean energy [2) to methane (CH4), bringing a much stronger greenhouse gas (CH4) to the atmosphere and causing an acceleration of global warming [R. palustris is able to express all three nitrogenases, making it an attractive model bacterium for in vivo studies of nitrogenase [R. palustris expresses nitrogenase and fixes nitrogen only when grown anaerobically with illumination . Therefore, a simple and reliable method that works well under anaerobic conditions could benefit the in vivo studies of nitrogenase regulation in photosynthetic bacteria.n nature . Diazotrmmonia NH by nitron energy . In addi warming . R. palurogenase ,6. HowevlacZ gene encoding β-galactosidase is another reporter gene that is commonly used in photosynthetic bacteria [Quantitative real-time PCR (qRT-PCR) is a regular method to measure the expression of target genes . In thisbacteria ,10,11. Abacteria ,13. Givebacteria .Aequorea victoria in 1960 [2) for the maturation of the fluorophore [Reporter systems are powerful tools for investigating transcriptional regulation. Green fluorescent protein (GFP), which is the first fluorescent protein being used to measure gene expression in prokaryotes and eukaryotes, was first isolated from  in 1960 ,17,18,19 in 1960 ,21,22, f in 1960 . As the  in 1960 . Howeverorophore . Little Here, we describe a simple and highly sensitive method capable of determining the nitrogenase gene expression by RFP reporter system in photosynthetic bacteria grown anaerobically. This method can be used to measure both the genome- and the plasmid-based nitrogenase gene expression and is also able to complete the analysis of large amounts of samples with tiny amounts of biomass in a short time.R. palustris strains were grown aerobically on defined mineral medium (PM) agar supplemented with 10 mM succinate at 30 °C [Escherichia coli S17-1 was grown in LB medium at 37 °C. When appropriate, R. palustris was grown with gentamicin at 100 μg mL−1. E. coli cultures were supplemented with gentamicin at 20 μg mL−1. R. palustris strains and R. rubrum UR2 were grown anaerobically in nitrogen-fixing medium (NFM) [2 gas was provided in the headspace of sealed culture tubes. 20 mM acetate was included as the carbon source and the medium was supplemented with 10 μM sodium molybdate (Na2MoO4). All cultures except E. coli strains were incubated anaerobically with illumination.For genetic manipulations, at 30 °C . EscherimCherry gene was created by PCR using the Q5 high-fidelity DNA polymerase to amplify three DNA fragments including upstream and downstream of the stop codon for nifK and mCherry gene with RBS. These fragments were then incorporated into PstI-digested pJQ200SK suicide vector using the T5 exonuclease-dependent assembly system [R. palustris CGA009 and R. palustris CGA676 by conjugation with E. coli S17-1, and double crossover events for allelic exchange were achieved using a selection and screening strategy as described previously [mCherry gene by PCR. The amplified mCherry was then incorporated into the EcoRI site of the broad-host-range plasmid pBBR1MCS-5 [SacI site, the resulting recombinant plasmid was mobilized into R. palustris CGA009, R. palustris CGA676 or R. rubrum UR2 by conjugation with E. coli S17-1. All engineered strains were verified by PCR and sequencing.All strains and plasmids used are listed in y system . Plasmideviously . For theBR1MCS-5 . After c660 nm and relative fluorescence intensity by a microplate reader , respectively. When measuring the relative fluorescence of RFP, the excitation and emission wavelengths were set to 587 nm and 610 nm, respectively.Cultures in log phases were harvested by centrifuging at 12,000 rpm for 1 min . The cell pellets were washed twice with 10 mM phosphate buffer (PBS). The cells were pelleted by centrifuging at 12,000 rpm for 1 min, and then were resuspended with 10 mM PBS. A 200 μL resuspended culture was then transferred to the 96-well clear and black plates for the measurement of ODnifD gene encoding a subunit of molybdenum nitrogenase were measured by qRT-PCR in different growing stages of R. palustris strains. R. palustris cells were firstly harvested from cultures grown to the early, mid and late log phases, respectively. After RNA extraction, cDNA was then prepared with 2 μg total RNA using FastKing-RT SuperMix  in a 20 μL reaction mixture, which was incubated at 42 °C for 15 min to remove the genomic DNA and complete the reverse transcription. Another incubation at 95 °C for 3 min was carried out to stop the enzyme reaction. Reactions were carried out using SuperReal PreMix Plus  with 50 ng cDNA and 0.5 mM of each primer  into the genome of R. palustris CGA009 immediately downstream of the nifHDK gene cluster encoding Mo nitrogenase. The generated nifHDK-mCherry gene cluster is transcribed into a single polycistronic mRNA from the nifH promoter where initiation of transcription is tightly regulated  under aerobic and anaerobic conditions. The same emission and excitation spectra were observed regardless of the bacterial cells grown aerobically or anaerobically when corresponding wavelengths of excitation monochromator and emission monochromator were set to 587 nm and 610 nm, respectively  and photosynthetic medium (PM) [mCherry-inserted nifA* mutant strain (CGA3006), whose mCherry has the same context as R. palustris CGA3005. As shown in R. palustris CGA3005 (CGA009-gRFP), a strain that does not express nitrogenase in PM, only produced fluorescent signals in NFM but not in PM, while R. palustris CGA3006 (nifA*-gRFP), a strain that is able to derepress the expression of nitrogenase even in the presence of fixed nitrogen, produced fluorescence in both NFM and PM. The fluorescence intensities were positively correlated with cell growth. These results suggest that R. palustris strains CGA3005 and CGA3006 express RFP and nitrogenase simultaneously when they are incubated anaerobically with illumination.The ium (PM) ,29. The R. palustris strains CGA3005 and CGA3006 did not show any significant fluctuations with the cell growth under conditions that express nitrogenase (nifD) expression of R. palustris strains CGA3005 and CGA3006 at early, mid and late log phases. The same as the results obtained by RFP reporter system, no nitrogenase gene expression was detected by qRT-PCR in R. palustris CGA3005 grown with ammonium  expressing mCherry with the promoter of R. palustris nifH (PRpnifH)  grown in PM, a condition that makes NifA inactive due to the presence of ammonium. When an additional NifA* was overexpressed with a strong promoter PJ23119 (CGA3009), high fluorescence intensities still could be detected in this CGA009-based strain grown with ammonium  A, which ammonium B. To detse genes C. These 2 to NH3 by nitrogenase is an energy-intensive process [R. palustris, which is widely distributed in the environment as a member of purple non-sulfur bacteria (PNSB), generates ATP required for nitrogenase activity from light by cyclic photophosphorylation under anaerobic conditions, making it attractive for the study of nitrogenase regulation [in vitro. Therefore, in vivo assays play an important role in understanding the nitrogenase regulation of the photosynthetic diazotrophs [lacZ reporter system are unable to measure nitrogenase gene expression in a timely manner [E. coli and Bacteroides fragilis as oxygen-independent fluorescence reporters [R. palustris at the emission wavelength of 492 nm (FbFPs) is 26-fold higher than that at 610 nm (mCherry). This means that mCherry will have a greater sensitivity than FbFPs if it is used as a fluorescence reporter in R. palustris. Therefore, we developed a simple and quick method for photosynthetic bacteria grown anaerobically to examine their nitrogenase gene expressions by RFP.Diazotrophs have developed sophisticated mechanisms to control nitrogenase expression and activity, as the reduction of N process . Photosygulation ,35. Givezotrophs . Howevery manner ,10. Thoueporters ,37, the R. palustris only expresses nitrogenase under anaerobic conditions, but contradictorily, RFP needs molecular oxygen for its chromophore maturation. Oxygen access is of great importance for molecular oxygen to get into the fully folded barrel protein, but it may also trigger irreversible photobleaching and reduced photostability of a fluorescent protein [R. palustris CGA3005 can be fully recovered after a 4-h oxygen exposure, and is able to maintain the maximal fluorescence intensity for a couple of hours  of 0.2–0.3 (lacZ reporter systems. In addition, the expression level of nitrogenase in nifA* strains grown in PM was relatively low. In this situation, the qRT-PCR method was not sensitive enough to accurately measure the nitrogenase gene expression, but the RFP reporter system was still highly reliable (lacZ reporter system in the photosynthetic bacterium Rhodobacter capsulatus [nditions . When R.detected . That th 0.2–0.3 , providireliable . These rpsulatus ,10, the R. palustris without barriers (R. palustris, the RFP reporter system also worked well in another photosynthetic bacterium R. rubrum that has an Fe-only nitrogenase gene cluster [The plasmid-based RFP reporter system, which can be used in barriers , is quit cluster , suggestlacZ reporter system, the RFP reporter system developed here is easy to operate and can quickly measure large amounts of samples with a high sensitivity, providing a better method for in vivo study of nitrogenase regulation in photosynthetic bacteria grown under anaerobic conditions. The RFP reporter system will contribute to a better understanding of the genetic regulation of nitrogenases, and can extend its applications to include other target genes and other anaerobic bacteria of interest.Regulation of gene expression is of great significance for microorganisms to switch their lifestyle in response to the environmental changes. Compared with the commonly used qRT-PCR and


Biosecurity breaches have been shown to play a major role in the introduction and spread of African swine fever (ASF) in domestic pig populations. The aim of the study was to describe the biosecurity levels and management practices of ASF outbreak and uninfected herds and to identify potential risk factors for ASF introduction. The biosecurity score of ASF outbreak herds was significantly lower compared to uninfected herds. This may reflect general improvement in the application of biosecurity measures over time in Estonian pig farms as the data on uninfected herds were collected later, at a time when intensified official controls may have had their effect. Larger herds were more at risk of being ‘outbreak herds’ compared to smaller herds. The biosecurity parameters significantly associated with ‘outbreak herd’ status in statistical analysis were mostly related to indirect contacts with the outside farm environment. The biosecurity barriers applied in Estonian pig farms have not been sufficient to avoid the introduction of ASF and need critical evaluation and improvement. Reduction of all contacts between the farm and the external environment should be emphasized in a situation where ASF is circulating in wild boar populations close to pig farms.Risk factors related to external biosecurity have been considered to play a major role in the introduction and spread of African swine fever (ASF) in domestic pig populations. The aim of the study was to describe the biosecurity levels and management practices of ASF outbreak and uninfected herds and to identify potential risk factors for ASF introduction. Data collected from the outbreak herds during outbreak investigations and from the randomly selected uninfected herds were analyzed. The biosecurity score in ASF outbreak herds was significantly lower compared to uninfected herds. However, this may reflect general improvement in the application of biosecurity measures in pig farms over time as the data on uninfected herds were collected later, at a time when intensified official controls may have had their effect. Larger herds were more at risk of being outbreak herds compared to smaller herds. The biosecurity parameters significantly associated with the outbreak herd status in multiple correspondence analysis were mostly related to indirect contacts with the outside farm environment. The biosecurity barriers applied in Estonian pig farms have not been sufficient to avoid ASF introduction and need critical evaluation and improvement. Reduction of all contacts between the farm and the external environment should be emphasized in a situation where ASF is circulating in wild boar populations close to pig farms. Application of biosecurity measures is considered, and has been proven to be, a primary tool to prevent the introduction and spread of infections in animal populations. In the case of African swine fever (ASF), many risk factors related to biosecurity have been shown to play a major role in spreading the disease and maintaining it in domestic pig populations. The most prominent risk factors are swill feeding and direct contacts between susceptible and infectious pigs  . Howevern = 27) from 2015 to 2017 in Estonia revealed that the most probable mode of transmission of the infection into the herds was indirect transmission by contaminated vehicles, humans or other fomites. Biosecurity breaches were identified in all outbreak herds. In some farms with high-level biosecurity measures only minor violations of biosecurity practices may have been the reason for incursion of the virus [Epidemiological investigations in ASF outbreak herds n = 2 from 201Various scoring systems have been used for the quantification of biosecurity levels of pig farms in different countries . UsuallyThe aim of the present paper is to describe the biosecurity levels in outbreak and in randomly selected uninfected herds utilizing the data collected during outbreak investigations and farm inspections. In addition, some parameters related to farm management of infected and uninfected farms are described. Due to the time shift between collection of the information from outbreak and uninfected herds, as well as some inconsistency in data collection, it is not possible to make a full comparison of these two groups. However, these observations could form a basis for raising hypotheses about potential risk factors for ASF introduction into pig herds that could be further investigated.n = 27).The group of outbreak herds in this study consisted of all ASF-infected herds detected in Estonia from 2015 to 2017 (n = 18) were extracted from outbreak investigation protocols compiled by the veterinary officers conducting the epidemiological investigations. In addition, the official veterinarians involved, and the farm owners or personnel of outbreak herds, were interviewed face to face or by telephone by the authors during the autumn of 2015 to collect additional information.The data from the 2015 outbreak herds  were collected by observations and face-to-face interviews during the outbreak investigations conducted by the authors on site.In 2016 and 2017, the data on outbreak herds  and were therefore considered as one epidemiological unit in the analysis. Thus, the final number of visited and assessed uninfected farms  was 28.The uninfected herds were selected randomly from the list of all herds in the national animal register using the random number generator in Microsoft Office Excel (MS Excel). The selected herds were located in 11 out of 15 counties of Estonia. Herds from four counties  were excluded by the random selection process. The number of herds in these counties was also the smallest (less than 10 herds per county).One of the herds in the uninfected group contracted ASF in summer 2017 and was moved to the group of outbreak herds in the analysis. One of the 27 reported outbreak herds proved to be uninfected in follow-up studies [The assessment of external biosecurity was performed using the same evaluation criteria (listed in In addition to biosecurity parameters (BSP) listed in The BSPs used and the scoring system are presented in BSPs were weighted according to importance using an analytic hierarchy process (AHP) , applyinThe averaged weights of the expert group were used to calculate the score for every assessment criterion by multiplying the score with the weight value and dividing the result by 10. For disinfection barriers at the gate and at the building  for every farm was calculated as the sum of individual weighted scores of every parameter. Higher score indicates a higher biosecurity level of the farm.In addition to BSPs, information on possible farm-management-related risk factors was collected. Exposure to these risk factors was compared between outbreak and uninfected herds.Univariable logistic regression analysis was used to assess the potential associations between the herd infection status and the biosecurity score as well as the studied risk factors. STATA 17 software  was usedp-value 0.05 [Multiple correspondence analysis (MCA) was conducted to demonstrate potential associations between the variables used for biosecurity scoring and farm outbreak/uninfected status. A two-dimensional symmetric map presenting the solution of two-way interactions of the variable categories was created including all 14 variables used for composing a herd’s BSS . These vlue 0.05 ,22. XLSTlue 0.05  was usedThe distribution map of study herds was developed with the STATA 17  softwareDistribution of outbreak and uninfected herds between herd size categories and production types are presented in The map with geographic distribution of outbreak and uninfected herds is presented in The BSS of all study herds ranged between 1.95 and 10.00 points with a median of 7.70. The frequency distributions of BSS of outbreak and uninfected herds are presented in The BSS are close to normally distributed in outbreak herds whereas in uninfected herds the distribution is negatively skewed .The summary statistics of BSS in outbreak and uninfected herds is presented in p = 0.03) in univariable logistic regression analysis. Production-related parameters had no significant effect on herds’ outbreak/uninfected status.The outbreak/uninfected status of the herd was significantly associated with the BSS of the herd Pets in contact with pigs Other production animals in contact with pigs Feeding freshly cut fodder Storing feed in bins or piles Unsafe storage of bedding materials No fence No disinfection of people at the entrance of the territory No disinfection of vehicles at the entrance of the territory Dysfunctional disinfection at the entrance of the territory Disinfection barrier at every entrance of the building is partly present ○Score value 0.2 ○Score value 0.4 Poor functionality of disinfection barrier at the entrance to the building:○Score value 0 ○Score value 0.25 Low safety of changing clothes before entering the pig facility:According to the results of the MCA analysis, herd outbreak/uninfected status was significantly associated with the first axis (F1) explaining 20.35% of the total variance . VariablData collection for this study was conducted over a three-year period from 2015 to 2017. The majority of the outbreak herds were from years 2015 and 2016 (three from 2017). All but one uninfected herd were visited in 2017. This must be taken into consideration when interpreting the results as since 2015 the biosecurity requirements for pig farms were tightened in Estonia and official inspections of farms became more frequent (at least twice a year). These measures have probably caused improvements in the biosecurity of farms overall.From outbreak and uninfected herds, data were collected by the same group of experts following the same study protocol. The questionnaire was discussed thoroughly by the team members before the assessments to ensure uniformity in evaluations. However, data collection for the 2015 outbreak herds was conducted retrospectively using the outbreak investigation protocols and questioning the people involved in outbreak management. This may have had some impact on evaluations of a more subjective nature  or some recall bias. Nevertheless, in general, we were able to retrieve the same information about 2015 outbreak-farms as during the farm visits conducted later. The interpretation of the collected information was uniform for all herds which reduced the effect of these differences in data collection.The uninfected herds were selected randomly from the whole population of Estonian pig herds. The geographical distribution of uninfected herds coincided with the geographical distribution of outbreak herds well . Just onThe biosecurity measures assessed in this study were mostly prescribed by national legislation  and inclThe biosecurity scoring was mainly based on counting the biosecurity elements present. In the case of a single visit to the farm, it was difficult to evaluate compliance with the biosecurity requirements by the farm personnel and visitors. Nevertheless, it was possible to evaluate, to some extent, the functionality of the disinfection barriers based on observations on site and methods used for disinfection, as well as the effectiveness of some biosecurity procedures, such as entering of people and vehicles into the pig-keeping rooms.To reflect the greater importance of some biosecurity measures and elements compared to others, the weights were incorporated into the calculation of the BSS using an analytic hierarchy process to evaluate the importance of different biosecurity measures. However, using the weighted scores compared to unweighted scores had only a little effect on the biosecurity level estimates of individual farms . The difference between the average scores of outbreak and uninfected groups was not significantly modified by applying weighted scores (data not shown).Multiple correspondence analysis was used to find management-related risk factors associated with herd outbreak/uninfected status. This method was chosen due to it being less sensitive to multicollinearity and because of a relatively small number of observations with a high number of explanatory variables. Nonetheless, since only two-way associations were analyzed, the effect of the associations was not adjusted for the influence of other factors, nor could interactions be tested ,22. TherThe results of the univariable analysis showed that the biosecurity level in uninfected herds was significantly higher than in outbreak herds. However, as mentioned above, this difference may reflect the improvement of biosecurity level in Estonian pig farms over the three-year period. The average BSS of the year 2017 outbreak herds was 8.8 being higher than the mean (7.9) of all uninfected herds. There is also some indirect evidence that may indicate that present biosecurity measures applied (or as applied) in pig farms might have not been sufficient to avoid ASF outbreaks in Estonian pig farms. First, the herd incidence of ASF outbreaks in Estonia did not change significantly over the years 2015–2017 being in the range of 2.1–2.6 outbreaks per 100 herd-years ,28,29. HDue to the small sample size of this study, we were not able to reliably compare the biosecurity levels of outbreak and uninfected herds in different herd size categories. Nevertheless, the average BSS was higher in larger herds compared to smaller ones (data not shown).If improvements in the meeting of formal biosecurity requirements have not reduced the risk of outbreaks, the reason may be that the applied measures are not effective enough or they are not properly applied . As an example, Estonian pig farmers have not been able  to introduce a washing step before disinfection of vehicles entering the farm territory. The spraying of vehicles is not compulsory and often only the wheels are disinfected by passing over a disinfection bath or mat. This may be insufficient to avoid the carriage of contaminant through the disinfection barrier even if proper waiting time is adhered to. The second reason may be that with applied biosecurity measures not all transmission routes are controlled. Due to the strong seasonal pattern in the occurrence of ASF outbreaks in domestic pigs (the summer season) the role of blood-sucking insects in virus transmission has been discussed ,31,32. IThe results of the multiple correspondence analysis (MCA) revealed three groups of factors potentially associated with the infection status of a herd: First, factors related to physical and disinfection barriers . Second, factors related to frequency of contacts to the ‘outside world’ . Third, factors related to storage and use of feed and bedding material. All these factors are mainly associated with indirect transmission routes of the infection and are consistent with the assumed virus introduction routes into outbreak herds identified during the outbreak investigations . This emThe MCA analysis did not reveal any significant associations between farm management indicators and the outbreak/uninfected status of herds. However, due to the small sample size of the study, we might not have been able to identify the less significant associations.It is evident that the biosecurity barriers applied in Estonian pig farms have not been sufficient to avoid ASF introductions. Outbreaks have occurred in farms where the level of biosecurity was evaluated as high. The herd incidence of outbreaks did not change significantly over the years  despite The biosecurity level in ASF outbreak herds  was significantly lower than in uninfected herds  in Estonia. However, this may reflect a general improvement in the application of biosecurity measures in pig farms over a three-year period.The factors associated with the ‘outbreak’ status of a herd included unsafe contacts with the outside farm environment, such as lack of fencing, lack of or poor disinfection barriers at the entrance of the farm territory for people and vehicles, poor safety procedures for changing clothes before entering the pig facility, contacts with other domestic animals, and entering of unnecessary vehicles on the territory of the farm.Another distinctive group of factors associated with outbreak status of the herd related to feed and bedding, such as feeding freshly cut fodder, storing feed in bins or piles, and unsafe storage of bedding materials.


C route (2- and 4-pass). The improvement of strength properties was obtained as a result of grain fragmentation in the CCE process. Changes in the microstructure were observed using a light microscope, and mechanical properties were measured in the microhardness test and a static tensile test. The obtained results showed that the mechanical properties of the alloy depend on the number of passes and the material deformation route. This observation was related to the fragmentation of its structure and strengthening, which resulted in changes in its properties. The highest strength was characterized by the material pressed four times with the rotation of 90° (BC route), whose properties were comparable and even slightly better than the material squeezed twelve times without rotation (A route).This study evaluates the impact of changing the deformation routes of the extrusion process in a cross-shaped die (CCE) on the structure and properties of a CuZn36 alloy (% at.). Samples with dimensions of Ø8 × 36 mm were subjected to extrusion at room temperature according to two variants: straight extrusion in the A route  and extrusion with interoperative rotation by 90° in the B The development of technology and the increasing requirements for structures in the construction and machine industry have resulted in the growing interest and demand for newer materials with better strength properties. One of the ways to improve the mechanical properties of materials is to reduce the grain size by plastic working. Along with reducing grain, the materials show much better mechanical properties . The fraBy limiting the possibility of free movement deformation and complex stress states, these methods allow us to obtain results not achievable by classical plastic working, making them quite attractive in terms of application ,5. The eAmong SPD techniques, the high-pressure torsion process is considered the most efficient . In thisThe most common SPD technique is based on the side extrusion process . The metIt is a relatively simple technology that allows us to obtain materials with UFG structures . The proT-shaped ECAP method [The second group consists of techniques based on developing a single angular channel to multichannel systems. An example of this is the P method ,17, wherP method . The menP method .This study evaluates the third aspect of material processing with SPD techniques. When a billet is reloaded into the fixture, it is possible to position it to undergo deformation with the same (basic) or rotated stress pattern. This process is called “changing of route deformation” . It is cA variant, the specimen is rotated in an alternating clockwise direction and the BC variant, only unidirectionally. For both variants, shearing occurs at different shearing planes for each pass, repeated after two successive passes without any inversion in the shearing direction for the BA route and after four passes with inversion of the shearing direction for BC. In route C, the specimen is rotated by 180° between subsequent passes, and the shearing plane is always the same in successive passes, but the shearing direction is inverted after each pass [In the scheme according to route A, the sample is processed without rotation between successive passes, and the shearing plane and direction are the same in both even and odd-numbered passes. Route B consists of rotating the sample by an angle of 90° around the extrusion axis, wherein in the Bach pass .The material properties strongly depend on the direction of its processing . For theThe results of the asymmetric rolling (ASR) process show that it leads to deformation much more efficiently, causing severe deformation or microstructural evolution and improving the ductility of the alloy in comparison with samples deformed by the classical method of symmetric rolling (CR) . By apprThe literature expresses the view that processing with the ECAP method reduces the occurrence of casting defects, such as shrinkage cavities and the separation of second-phase particles by breaking and dispersing them in the alloy matrix, and affects grain refinement by breaking up coarse dendrites ,29,30. HC route. Others [C route provides a finer microstructure compared to other routes [Shaeri et al.  reported. Others  investig. Others  came to r routes .C route leads to the location of deformation in the eutectic phases and a decrease in elongation to alloy fracture compared to the case of A [C-ECAP deformation was the most efficient in terms of deformation and microhardness increase, and the grain size after two passes was reduced by more than two times, regardless of the route type. Gao et al. [C, it has a positive effect on the homogeneity of deformation of AA6063 alloy, noting that variant C is only slightly inferior in terms of strength and plasticity. Increasing the number of passes to 6–8 leads to a further decrease in the grain size and improvement of the homogeneity of the structure and only a slight increase in hardness and strength, with little preference for the BC or C route in this regard [C route.Research on the impact of the ECAP deformation routes on the mechanical properties of Al-Si alloys showed that processing according to the Base of A . In the ase of A , it was ase of A  reportedo et al.  showed ts regard ,40,41. Hs regard  found thInteresting effects were noted when the extrusion method was combined with the cyclic change of the deformation path by the oscillating die, the so-called KOBO . In thisIt should also be added that repeating the deformation pattern may slightly weaken the material hardening effect in even passages. This is due to the opposite direction of deformation causing the Bauschinger effect . Wang etA relatively recently appeared method known for SPD techniques is cross channel extrusion CCE  or crossFEM numerical simulations  and expeHowever, over decades since Chou patented the CCE method , the infA single-phase brass CuZn36 alloy, characterized by high susceptibility to cold forming, was selected for the tests. The material as delivered was in the form of a drawn bar with a diameter of 8 mm. Before the extrusion, to eliminate the hardening effects, the test material was subjected to recrystallization annealing at a temperature of 550 °C for one hour and then cooled in a furnace to room temperature. The material after such pretreatment is referred to in this paper as the initial material.╬). However, the deformation of the workpiece in the cross channel differs from that of the conventional single channel [The CCE system resembles ECAP by its quadruple multiplication . The microstructure was analyzed using a Nikon MA200 metallographic microscope , and the grain size was determined using the dedicated computer program NIS-Elements by Nikon.The samples were cut parallel to the extrusion direction (X-Y) from the central parts by an electrodischarge machining (EDM) device and then ground on SiC paper with a gradation of 100–4000, polished with 3–0.25 μm diamond suspensions and etched with the “Kalinge’s” reagent  program developed contour maps of the microhardness distribution. They provide a visualization of the hardness and homogeneity distribution in the billet by assigning a given level to a specific color.The mechanical properties of the samples were evaluated using an Instron 8801 testing machine  with two speeds: 1 mm·sC-CCE.The material structure in its initial state, i.e., after recrystallization annealing, is shown in X-axis of the extruded sample  were slightly distorted toward the outer surfaces, related to passage through the shear plane. As the number of passes increases, the deformation of the material increases. As shown in C route. As a result of the rotation of the sample by an angle of 90°, the shear bands formed in the first pass intersected with new second pass bands  was 86 HV0.2. The changes in the microhardness of the investigated alloy after deformation are presented as macromaps covering ¼ of the longitudinal section area (X-Y) of the sample . The lowC route, the material’s behavior was similar to that in the previous case, but the obtained microhardness values were greater for the same number of passes. It can be said that the material strengthening after two passes in the BC variant corresponds to 4× in the A-route, and 4× in BC was close to the 12× A-route. Additionally, the strengthening in zone C is generally higher, and they are quickly reduced by homogenization with the rest of the material.In the case of deformation in the BC route of the CCE process. Additionally, the results of the initial state are also shown. C-CCE variant, the material shows an even faster and greater increase in strength at the expense of its elongation. 2× in BC-CCE is higher than 8× in A-CCE and is close to 12× in A-CCE.The yield point and tensile strength showed a substantial increase from 76 and 307 MPa to 650 and 730 MPa, respectively, after two passes in A-CCE. These results, combined with a drastic decrease in elongation to ~9.8%, indicated a strong deformation strengthening of the material. The increase in deformation leads to a further increase in these parameters, even up to 920 and 948 MPa. This is equivalent to an almost threefold increase from the initial state. However, in the BRegardless of the variant of the deformation route, the material reached very high strength parameters after just two passes. High YS/UTS ratio values indicated a low yield point of the material and the need for even partial recrystallization of the alloy.C route was a process of excess stress. The slip in the first and second passes was limited by the slip in the third and fourth passes, respectively. Therefore, the even passes showed lower strength than the odd passes. However, in route A, different shear planes provide additional deformation and increase in strength more than in the case of deformation according to the BC variant. However, the intersection of planes and shear directions in BC results in more complex systems and may result in higher strength and ductility of the processed material, as demonstrated in this paper for the CCE method.Damavandi et al.  analyzedAccording to the model proposed by Sakai , shear bC divide the grain much more efficiently than in variant A. This resulted in a much faster fragmentation of the structure. Processing with a variable deformation route thus improves the homogeneity [C should be related to the beginning of transformations initiated by dynamic recrystallization of the deformed material [Changing the sample orientation between successive passes, therefore, leads to different combinations of grain shape and size, as shown in ogeneity . Often nogeneity , in the material . It alsoObservations of the material strengthening visualized with the help of contour maps of microhardness distributions significantly facilitate the analysis of the deformation process and change its route to the process of homogenization of the material structure. The obtained results show that processing with SPD methods leads to a high level of hardness in the first passes , which iThe refinement of the grain as a result of processing with the CCE method causes the alloy, plastic in its initial state, to achieve a very high strength after processing at the level of good-quality structural steel. This was accompanied by a substantial increase in the YS/UTS ratio and a decrease in the plasticity reserve of the material. From the constructor’s point of view, this is a disadvantage, but it may turn out to be an advantage in specific applications.Considering the abovementioned, it seemed appropriate to utilize advanced techniques for characterizing the material’s structure, such as SEM-EBSD, TEM electron microscopy, or XRD texture analysis. The author intends to supplement this area of knowledge in the near future.The change of route deformation can be realized not only by the rotation of the sample but also by changing the geometrical parameters. Li et al.  modifiedQuite recently, Zhuo et al.  presenteC routes.This study presented the results of processing the CuZn36 (at.%) alloy with a less popular method of extrusion in the CCE cross channel , using aThe CCE method was related to the ECAP method. However, due to the shape of the intersecting channels, deformation is a more complex process. The CCE method eliminates the problems found in ECAP, such as channel bottom friction or “corner gaps”, but requires greater demands on the control of the process. The basic deformation method was also shear, but a significant share of triaxial compression leads to the formation of a paraxial zone of very strong deformation. It is a potential source of structural changes. Unfortunately, its presence increases the heterogeneity of the material.The increase in deformation resulting from the multiplication of the number of passes of the billet through the matrix system, regardless of the adopted pattern of the deformation route, leads to a substantial strengthening of the alloy. The effect of this was also an increase in microhardness, its propagation throughout the sample volume, and an increase in the homogeneity of the structure. The observed decrease in grain size was also responsible for the increase in strength.C route, as a result of rotating the sample at an angle of 90°, the deformation planes intersect, generating the shear bands and microbands that efficiently divide the grain into parallelogram grains. The amount of energy accumulated in this way was so significant that the beginning of dynamic recrystallization was observed. The strain efficiency in the BC route was much greater than that in A. It can be said that processing 2× in BC by CCE corresponds to 8× in A, and 4× in BC gives higher values than 12× in the A route.In the A route, processing of the material leads to a substantial increase in the strength properties of the material, with a clear division into the types of its structure. In the B


This paper presents the characteristics of a modernized rotary hammer equipped with a new measuring system based on strain gauges for recording short-term signals. The stand makes it possible to carry out dynamic tensile and bending tests in the range of linear speed of the exciting element from 5 to 40 m/s. Initial tests of dynamic deformation and structural studies in the form of fractures carried out on a representative group of metallic materials allowed determining the correlation “strain rate–strain structure”. The proposed new methodology of dynamic materials testing is an original achievement of the authors and may be an effective tool for assessing the properties of construction materials under conditions of dynamic deformation. In practice, the test results can be used to design the structures of energy-consuming elements of vehicles and aircraft load-bearing elements subjected to dynamic loads. Having an extensive database of results from dynamic tests will allow verifying the correctness of calculations of the structure with the use of the finite element method. Currently, the possibility of conducting research and determining material characteristics under conditions of high strain rates is limited by the availability of test equipment, the ambiguity of the applied methods, calculation procedures and the complexity of the phenomena accompanying these deformation methods ,2,3,4. T−1.The priority of the safety of users of means of transport poses more and more challenges to designers and technologists regarding the mechanical and functional properties of construction materials, and acceptance tests of new materials and construction elements are increasingly demanding. The most commonly used methods of assessing the plasticity of materials are tensile, compression, torsion and impact tests, as well as model upsetting and rolling tests ,6. Used −1. Even the very modern and widely used test system in materials research “Gleeble” allows carrying out tests with a strain rate in the range from 0.0001 to 100 s−1 [−1–105 s−1 are obtained, the problem is the availability of the apparatus and the complexity of the procedures for analyzing the results [In the torsional plastometer test, the maximum strain rates are in the order of 10 s 100 s−1 ,8,9. The results ,12. Most2 to 104 s−1 is provided by rotary hammers. These devices are characterized by a compact design and an uncomplicated test method. An additional advantage of these devices is the possibility of testing samples made of rods as well as coating materials, sheets and strips. This versatility of application, a large range of deformation rates and a relatively low cost of making test samples encourage the search for the possibility of using these devices in testing materials [The possibility of testing materials with deformation rates from 10aterials ,14,15,16t) is very similar. The reliability of the results obtained must not be in doubt. In a few research centers, teams have the ability to verify their measurement systems.The mechanical design of the device is not new. The rotary hammer has been completely upgraded and equipped with a new registration system. Rotary hammers were used in the 1970s. There are few such devices in Europe. Certainly, three devices are also in Poland, and a few are in Germany. There are more of these devices in Germany because they were constructed there. These devices operate on the basis of various measurement systems, which are the result of many years of work of research teams. For example, a rotary hammer operating at the Wrocław University of Technology has a measuring system similar to Hopkinson’s rod measuring system . It is e2 s−1 and higher, is a serious experimental problem” [The problem of dynamic deformation tests, also carried out on rotary hammers, is the course of the obtained force characteristics and their interpretation. Professor Janusz Klepaczko, who devoted his entire scientific life to the problems of plastic deformation of materials under dynamic loads and the accompanying phenomena, stated that “learning about the plastic properties of metals deformed with high strain rates, of the order of 5 × 10problem” . There a−1. The purpose of the work is to present the device and the original test methodology, which will certainly work in both scientific and industrial laboratory conditions [The rotary hammer is characterized by ease of use, simplicity of the recording system and uncomplicated sample geometry. The method of implementation of the test is similar to a static tensile test and a simple bending test. The authors’ intention is to interest the scientific community in a new research method. The use of dynamic plasticity characteristics in new materials and design processes is insufficient. There are no material characteristics available under high-speed deformation conditions above 500 snditions ,21,22,232 to 104 s−1. During the dynamic tensile tests, the sample is connected to the upper grip and is subjected to deformation by hitting the hammer (claw) against the anvil of the lower grip. On the other hand, during impact bending, the sample is broken on the anvil with a hammer claw (The tests of dynamic deformation were carried out on a rotary hammer of the RSO (rotary impact hammer) type shown in mer claw . The repForce sensor and strain gauge;Encoder and module f/U for assigning frequency changes to voltage changes;Measuring card with 16-bit A/C converters;Computer PC.The rotary hammer measuring system developed and made for measuring the force  and linear speed of the beater consists of the following basic components:The diagram of the measuring system with optional expandability of the system is shown in Steel with the TRIP effect—after hot rolling (last pass 910 °C)—structure: ferrite + bainite + residual austenite;DP-type steel—hardening in water in the range of ferrite + austenite (temperature 810 °C)—structure: ferrite + martensite;AZ31 magnesium alloy after hot rolling—annealing 350 °C/1 h/air;PA4 aluminum alloy—supersaturation from the temperature of 500 °C/1 h/water.Temperature measurement is an essential issue in the optional scheme of the device due to the dynamic deformation in adiabatic conditions, without heat transfer with the environment. Knowing the temperature increase of the material during deformation will allow a proper assessment of microstructural changes caused by high deformation speed. The tests of dynamic deformation were carried out in tensile and bend tests. The test specimens were made of the following metallic materials: steel with the TRIP effect, steel type DP, magnesium alloys AZ31 and aluminum PA4. These materials were subjected to heat treatment in order to obtain the desired and homogeneous initial structure: 2). A larger sample diameter could damage the beater or device. In the case of steels prone to TRIP fortification (in the publication), the sample was broken within the upper measuring range of the strain gauge (25 kN).In the tensile tests, smooth cylindrical samples with a diameter of 4 mm and a measuring part length of 20 mm were used, threaded on both sides in the grip part . The sam2–6.5 × 103 s−1. During the tests, the course of the tensile and bending forces was recorded as a function of time and the linear velocity of the hammer located in the flywheel. From the force characteristics and measurements of the sample geometry before and after deformation, the following were determined: deformation velocity, tensile strength, limit deformation and impact strength.In the impact bending tests on a rotational and Charpa-type pendulum, standardized samples were used, made of a bar with a square cross-section of 10 × 10 mm and a length of 55 mm, with a “v” notch with a depth of 2 mm. These tests were carried out for the PA4 aluminum alloy. Tests of dynamic deformation on a rotary hammer were carried out in the range of the hammer linear speed of 5–30 m/s. This corresponds to the obtained deformation velocities in the range of 3 × 10gε—limit deformation;S0—the initial cross-section of the measuring part of the sample;S1—cross-section of the sample after deformation at the site of local narrowing (in the neck);d0—initial diameter of the sample (mm);d1—minimum diameter of the specimen after rupture (mm).Boundary deformation is defined in logarithmic measure, which is also called a natural measure or Hencky measure. They use the principle of constant volume reduction in the continuous volume of the boundary deformation, which is used in the analysis of plastic deformation processes, determined by the following Equation (1):−1);gε—limit deformation;t—time (s).The deformation velocities corresponding to the given hammer linear velocities were calculated from the ratio of the limit deformation εg to the test duration t:The deformation speed determined from Equation (2) is the average speed. The deformation εg (log measure) is related to the duration of the deformation, from the moment the beater came into contact with the anvil to the breaking of the sample. Determining the deformation speed from the elongation of the sample is difficult due to the deformation of the measuring part. It is impossible to use an extensometer elongation measurement as in a static tensile test because classical extensometers do not allow the elongation to be measured in such short deformation times. In addition, the dynamic deformation course will definitely damage the elements of the extensometer, hence the measurement of deformation from the change in sample cross-section.t,bU—toughness in the tensile, bending test (J/cm2);uL—work of deformation at rupture (J);A—initial section of the sample (cm2).The impact strength was determined from Formula (3): 2. The deformation work for tensile and bending attempts on rotational dents is determined as the area of the surface under the tensile or bending curve F = f(Δl). The breaking work for attempts to bend on the Charpa pendulum was read directly from the device registration system.Equation (3) is the standard equation for determining toughness. The number of deformation operations is expressed in J, and the surface area of the sample measuring part is expressed in cmRegardless of the dynamic deformation tests, tensile tests under static conditions on universal a testing machine and bending tests were carried out on a Charpy pendulum hammer with an initial impact energy of 300 J. The same standardized samples were used in the bending tests on pendulum and rotary hammers. The breakthroughs were identified on a Hitachi S-3400 N scanning microscope.During the deformation tests, the course of forces was recorded depending on the time. Examples of the recorded tensile forces for TRIP steel are shown in The dependence of the tensile strength of TRIP and DP steels on the deformation rate is shown in The dependence of the tensile strength of the PA4 and AZ31 alloys on the strain rate is shown in g = 0.32, half lower than that obtained in static conditions (εg = 0.66). It follows that with the increase in the deformation rate (the linear speed of the ram), the susceptibility of the AZ31 magnesium alloy to plastic deformation decreases. The plasticity reserve of the material is exhausted. The limit deformation of AZ31 magnesium alloy clearly decreases with the increase in the deformation velocity, and for the velocity v = 30 m/s, it reaches the value of εThe results of the impact strength tests in the dynamic stretching tests showed an increase in the impact strength of TRIP and DP steels a. The na2, respectively. This proves the high sensitivity of the rotary hammer measuring system also in the initial range of the hammer’s linear speed and confirms the correctness of the system indications. The performed impact bending tests on the rotary hammer of the PA4 aluminum alloy showed that the impact strength increases with the linear speed of the hammer and is greater than the impact strength determined in the standard bending test on the pendulum hammer . The linThe tests of selected metallic materials showed significant changes in mechanical properties with an increase in the strain rate compared to those obtained in quasi-static conditions and in standard impact tests (Charpy hammer bending test). The results of the endurance tests were confirmed by microfractographic studies of the identification of the fractures on a scanning microscope. Attempting to stretch on a flywheel machine in a technically simple way gives this possibility, hence the results of microfractographic studies in publications. Compression tests on Hopkinson’s modified rods do not identify breakthroughs because the sample is not destroyed.Microfractographic tests of TRIP and DP steels showed the ductile form of fractures of samples stretched under static conditions and dynamically deformed regardless of the linear speed of the hammer. In the morphology of fractures, pits characteristic for ductile cracking and cracks running through the grains along the cleavage planes were observed . A signiIn the nonferrous alloys PA4 and AZ31, the nature of the fractures was varied . In the TRIP and DP steels showed good plastic properties in the entire range of the linear speed of the hammer and a high tendency to intensively strengthen with an increase in the strain rate. This confirms the great usefulness of these construction materials in the construction of vehicle bodies, both in the technological process of manufacturing and during the operation of ready-made elements responsible for passive safety. In nonferrous alloys, in the morphology of fractures, the occurrence of areas of brittle fracture can be observed, which indicates the need for additional analyzes allowing the material to build dynamically loaded structural elements of vehicles and airplanes.The conducted analysis of selected metallic materials does not exhaust the entire problem of the influence of high strain rates on mechanical and microstructural properties. However, it indicates the existence of a significant dependence between the dynamics of the deformation course and the mechanical properties and structural phenomena accompanying high rates of deformation.There are few publications in the literature that present similar research results and discuss the possibilities of using the obtained databases in the structure design process . This isThe developed measuring system of the rotary hammer meets the requirements of recording quick and short-term signals of force and linear speed of the exciting element. The proposed research methodology is universal and applicable to a large group of metallic materials, from highly hardening modern structural steels used in the automotive industry, to nonferrous metal alloys commonly used in aircraft structures.The number of dynamic deformation tests carried out on the bench in many research projects is very large and concerns a significant group of materials, steels and nonferrous metal alloys. Thus, statistical analyses of the results are also foreseen in order to determine a sufficient number of tests for the individual material to know the collective distribution in terms of the selected resulting characteristic and the type of relationship between factors, e.g., the linear speed of the forcing element and the strengthening of the material and structural changes. Currently, research is focused on improving the research and measurement technique—temperature measurement. The measurement of the sample temperature is essential for the correct microstructural assessment of the material due to the fact that the dynamic deformation takes place under adiabatic conditions, without replacing the flat with the environment.The possibilities of using new construction materials in the automotive and aviation industries are more and more often determined by their resistance to shock loads, hence the need to develop new methods of testing materials under conditions of dynamic deformation and continuous improvement of measurement techniques. It is also necessary to develop a standard procedure that allows for an unequivocal evaluation of the results of dynamic deformation tests obtained in various kinematic conditions of the course of the experiment.


Cannabis sativa L.) from the Dacia Secuieni and Zenit varieties, compared to wheat flour, was studied in this research. The aim was to present the characterization of 2 varieties, out of the 70 accepted in Europe, for human consumption. The varieties selected from hemp meet the THC level requirement  in seeds. Hemp flour was obtained by grinding. The flour samples were evaluated for physicochemical parameters , the content of micro and macro elements, fatty acids, amino acids, and carbohydrates. The total proteins in hemp flour are found in larger quantities by over 35% compared to wheat flour, and the lipids reach the threshold of 28%. The amount of mineral substances exceeds 3% in hemp flour, and the fibers exceed 26%, compared to 0.61% for wheat flour. The predominant mineral substances were K, Ca, Mg, p, Fe, and Mn. The predominant fatty acids were the unsaturated ones, predominantly being linoleic acid, followed by oleic and gamma-linoleic acid. In the case of amino acids, the highest amount is found in glutamic acid for hemp flours. As for carbohydrates, sucrose is found in the largest amount, followed by glucose and fructose. In conclusion, hemp flours have superior non-traditional characteristics to wheat flour, being a potential raw material for fortifying food or using them as such, having beneficial effects of consumption on the proper functioning of the human body.The advanced characterization of flour from hemp seeds (edible fruits of  Cannabis sativa L. belongs to the Cannabaceae family and is an herbaceous, anemophilous plant and is known as hemp, being one of the oldest cultivated plants. Most of the existing data show that they were first cultivated in Central Asia, and in Europe, the first available data on hemp are from the Bronze Age [Cannabis sativa L.) has the highest industrialization capacity of all technical plants, where everything is used, and nothing is thrown away [Cannabis sativa ssp. Culta represents cultivated hemp and Cannabis sativa ssp. Spontanea represents wild hemp. At the present moment, the domestic form is cultivated both in Asian countries and in Europe, the United States, Canada, and Africa. It is cultivated for the diversity of fields of application such as agriculture, animal feed, pharmaceutical industry, food industry, and construction [onze Age ,2. Hemp own away . Accordiown away , hemp istruction .The main factor that causes confusion is related to the presence of the two phytochemicals specific to this plant, delta−9-tetrahydrocannabinol (THC) and non-psychoactive cannabidiol (CBD), the only psychoactive and toxic compound of the plant. These compounds belong to the class of cannabinoids and the family of terpenophenolic compounds. They are synthesized, then collected, and finally stored in specialized tiny secretory epidermal glands (glandular trichomes) ,6. TheseC. sativa L. hemp was reintroduced for industrial purposes and only those plants with low THC levels  [From this point of view, following the awareness of the psychotropic activity of THC and the harmful effects of the consumption of hemp flowers and leaves, on human health, many countries have begun to take measures to stop consumption. The first measures were taken by the USA and Canada, and then in Europe. Starting with 2013, with the appearance of the EU regulation no. 1307/2013, the cultivation of g parts)  and in 2g parts) .The total amount of lipids reported for hemp seeds is between 25% and 35% ,14,15,16Proteins, reported in an amount ranging from 20–25%, are easy to digest and rich in essential amino acids ,17,20,21Total carbohydrates are found in hemp seeds in a proportion of 20–30%, and a large part of them are dietary fiber, mainly insoluble ,21. Howep), magnesium (Mg), potassium (K), sodium (Na), and calcium (Ca), and in the category of trace elements, the majority were iron (Fe), zinc (Zn), manganese (Mn) and copper (Cu) [The total mineral content is indicated by ash, which is the anorganic matter of a sample. In the case of hemp seeds, it is between 3.7% and 5.9%, depending on the variety, environmental conditions, compost, the use of various fertilizers in the soil, as well as the use of various fertilizers. These substances fall into the category of micronutrients because the food requirement is small , but very important, playing an essential role in the proper functioning of the human body. The main macroelements reported in hemp seeds are phosphorus (per (Cu) ,15,20.With the awareness of the high nutritional value of hemp seeds, interest in the food industry began to grow. There is still confusion among the population about “industrial hemp” and “drug hemp”, even though there is legislation on this subject and sufficient sources of information. However, the negative reputation of the drug hemp influences consumption and investment for new perspectives .C. sativa L., prerequisites and regulated in the European Union Plant Variety Database [Although there is significant information in the literature on the nutritional composition of hemp seeds in general, there are no specific studies on the varieties allowed for consumption and their functional potential. Currently, there are about 70 varieties of hemp Database ,32. The Database .Thus, this study aims to characterize two varieties of hemp out of the approximately 70 accepted in Europe, the Dacia Secuieni variety and the Zenit variety (THC < 0.2%), compared to wheat flour to illustrate the benefits of hemp flour and to open new directions of research, hemp can be used as an adjunct in the production of functional foods. One of these directions can be the bakery industry, being one of the basic branches of the food industry.The total proteins from hemp flour are found in larger quantities by over 35% compared to wheat flour. The highest percentage is present in hemp flour of Dacia Secuieni variety, 25.19%. In the case of wheat flour, the percentage being only 13.04%. Values of 25.6% are also reported by Mattila et al.  or 24.8%Regarding the amount of lipids, there is a very high lipid content in the case of hemp flour 28.32% for Zenit variety, respectively 29.27% for Dacia Secuieni, compared to wheat 0.26%. Similar values were reported by Vonapartis et al.  and MattThe ash content in wheat flour is 0.55%, within the limits imposed by the classification of flour types according to the amount of ash . RegardiFollowing the results of the statistical analysis, it is observed that wheat flour has, except for moisture, a significantly lower value of crude protein compared to both varieties of hemp flour, between which there are no significant differences. The same scenario is repeated for lipids, crude fiber, and minerals, where wheat flour has the lowest values with significant differences from hemp flour variants.Following the data in p). The results obtained , Cr, Ni, and Pb. Compared to the samples of hemp flour, the sample of wheat flour records the smallest amounts of mineral elements, some of which are even absent. These high values of mineral substances support the proposal to fortify wheat flour with hemp flour.Following the analyses performed, 12 mineral elements were determined: copper (Cu), cadmium (Cd), chromium (Cr), nickel (Ni), lead (Pb), zinc (Zn), iron (Fe), manganese (Mn), calcium (Ca), magnesium (Mg), potassium (K), and phosphorus , with average values of 461.35 mg/100 g, these being considered optimal sources of p [p, and Mg, these being found in larger quantities after peeling. Considering the toxicity of Cd on the human body and the studies on hemp seeds where the maximum allowed limit is far exceeded [Following food requirements, mineral substances can be classified into macro elements in the case of minerals required in the amount of >50 mg/day, including K, eir type ,16,20,21arieties ,14,15,20ces of p . The amoces of p  or hazelces of p . Even ifexceeded , we can p, between Dacia hemp flour Szeklers with Fe and Mn, and in the case of hemp flour of Zenit variety with the elements Cd, Cr, Ni, Ca, and Mg.Following the Pearson correlation  regardinRegarding the fatty acid content, nine saturated and unsaturated fatty acids were identified in wheat flour, hemp flour of Zenit, and Dacia Secuieni varieties, respectively: The saturated fatty acids identified are myristic acid, palmitic acid, stearic acid, margaric acid, arachidic acid. The identified unsaturated fatty acids are oleic acid, linoleic acid, gamma-linolenic acid, and palmitoleic acid.According to the data in The low percentage fatty acids in wheat flour were: myristic acid, stearic acid, gamma-linoleic acid, margaric acid, palmitoleic acid, arachidic acid. In the case of the presence of acids in hemp flour, a significantly high percentage was given by oleic acid 23.6 g/100 g for the Dacia Secuineni variety and 20.58 g/100 g for the Zenit variety, respectively; and gamma-linolenic where their percentage being close. As in the case of wheat flour, myristic, margaric, palmitoleic, and arachidic acids are found in very small percentages.The results in the literature are similar to those obtained by us. Thus, hemp seeds are characterized by a high content of unsaturated fatty acids and low amounts of saturated fatty acids. Moreover, unsaturated fatty acids are found in amounts of up to 90% . They caFollowing the results of the Pearson correlation , we notiFrom a nutritional point of view, the quality of proteins is given by their composition in amino acids and their bioavailability. The amino acids identified in both hemp flour and wheat flour are: lysine, isoleucine, phenylalanine, these being part of the category of essential amino acids; as well as arginine, glutamic acid, cysteine, tyrosine, these being part of the category of non-essential amino acids; according to In the largest quantity in hemp seeds, glutamic acid is found both in the Dacia Secuieni variety and in the Zenit variety, according to Following the results of the Pearson correlation , we notiThe amount of individual carbohydrates identified in hemp flours and wheat flour are sucrose, glucose, and fructose. The highest amount was identified in the case of sucrose, followed by glucose and fructose, regardless of the type of flour studied, according to Authors such as Callaway et al.  studied In the case of wheat flour, the results obtained are similar to those reported by Schmidt et al. , who stuCannabis Sativa L.) from Dacia Secuieni and Zenit varieties, which were ground to obtain hemp flours.The study material used to perform the experiments consists of wheat flour sample, type 550, and hemp samples , and other reagents from Merck, Germany, were used. Three determinations were performed.An application was made using the GC-MS system (gas-chromatograph coupled with a mass spectrophotometer) of a sensitive analytical method to be able to identify fatty acids from composite flour samples. With the help of the BF3-MeOH method, the methyl esterification of the samples used in the analysis was performed. This occurred after the alkaline hydrolysis process. For a 20 mg oil sample, 2 mL 0.5 mol/L methanol solution was added, and the mixture was heated for 7 min at 100 °C. After cooling, 3 mL of BF3-MeOH having a concentration of 14% was added, and the vessel was heated for 5 min at 100 °C. After cooling, 7 mL of saturated NaCl solution was added, after which the solution was extracted. The resulting hexane layer (2 mL) was used as a solution for gas chromatography . The FAMp/N 055407). Mobile phases: E1: water; E2: 250 mM NaOH and E3: 1 M NaAc, gradient, mobile phase flow (0.25 mL/min). Reference electrode: pH/Ag/AbCl, column temperature being 30 °C.Determination of amino acids using high-performance liquid chromatography (HPLC) involves their acid hydrolysis in the presence of 6 M HCL except for sulfur amino acids, identification, and chromatographic dosing where the DIONEX ICS—3000 amino acid analyzer is used. Take 0.5 g of the sample and hydrolyze with 10 mL of 6 M HCl at 100 °C for 24 h. The sample is filtered through a 0.2 μm Millipore filter, and the sample is diluted in a ratio of 1:10 or 1:1000 with 0.1 N HCl depending on the nature of the sample, finally injected into the chromatograph. Chromatographic conditions: chromatographic column pre-column AMINOPAC PA10 . The equipment used consisted of: Jasco HPLC chromatograph (Japan) for analysis, it is equipped with an HPLC pump (Model PU−980), a column thermostat Model CO−2060 Plus, ternary gradient unit Model LG−980–02, UV-VIS detector (Model UV−975), injection valve equipped with a 20 µL test loop (Rheodyne) and detector with refractive index Model RI−2031 Plus. The samples were injected with a Hamilton Rheodyne syringe (50 mL). The HPLC system was controlled, and the experimental data were performed using ChromPass software. For the construction of the calibration curve, a standard mixture of carbohydrates with different dilutions (5 concentrations) was used, being between 333 and 2000 µg/mL. This HPLC-RI method developed by Filip et al. [The HPLC-RI method consists of separating at a temperature of 70 °C on a column of CARBOSep COREGel 87 C (300 × 7.8 mm) with a CARBOSep 87 C cartridge and CARBOSep COREGel 87 C cartridge. The mobile phase was represented by ultrapure Millipore water, and the flow rate was 0.5 mL/min., For the determination of glucose, sucrose, and fructose, and the injector volume was 20 µL. The process of extracting carbohydrates from the samples studied was performed in water. Weigh 3 g of the sample and grind it well, then add 8 mL of extraction solvent water. The mixture was ultrasonified for 15 min and then centrifuged for a period of 20 min at 4500 rpm. The supernatant was filtered through a 0.45 μm filter and injected into HPLC. Carbohydrate amounts were expressed in mg carbohydrate/100 g sample. The following materials were used in the determination of carbohydrates: acetonitrile (HPLC purity), it was purchased from Merck , the standards of resveratrol, fructose, sucrose, and glucose were purchased from the United States, from Milwaukee, Aldrich, Millipore ultrapure water  or in the opposite direction (negative correlation). The term correlation is used in the context of a linear relationship between two continuous variables and expressed as a Pearson product-moment correlation .Given that in recent years the interest for consumption in the food industry of hemp seeds has increased, it is of great interest to know the chemical composition of the varieties allowed from a legislative point of view. The two varieties of hemp studied: Dacia Secuieni and Zenit meet the THC level requirement . Analyzes showed that these varieties have an increased nutritional value, a high content of protein, fat, minerals, fiber, essential fatty acids, and essential amino acids. All these values, much lower than those found in wheat flour, make the hemp flour from this type of seeds much more qualitative. The entire composition of hemp seeds, but emphasizing the high amount of essential fatty acids and essential amino acids, it is recommended to use hemp seed flour for beneficial effects on the proper functioning of the human body. Hemp flour is an important vector in the food industry because it can be used in many different food technologies, such as beer, sugar, or the bakery industry.