THE USE OF MULTIPLE COMBINED NON DESTRUCTIVE TESTING IN THE CONCRETE STRENGHT ASSESSENT : APPLICATIONS ON LABORATORY SPECIMENS
In this paper a series of non-destructive tests has been performed with the purpose to investigate on the mechanical properties of the concrete employed in the civil buildings. A series of specimens were prepared in order to correlate the “in situ” concrete strengths obtained by multiple combinated non-destructive methods with the cubical and cylindrical strength obtained by destructive methods. The multiple combined methods (SonReb Methods + Windsor Probe Tests) were used to quality control and strength estimation of the concrete. In particular, a series of specimens by aggregates having various Mohs’Hardness (inert of fluvial origin) and by aggregate with only a class of Mohs’Hardness (crushed aggregate) has been prepared. During the concrete casting a series of cubical specimens has been prepared. The comparison among non-destructive tests, cubical strength and cores strength are carried out.
Utilization of Combined NDT in the Concrete Strength Evaluation of Core Specimen from Existing Building
In this paper, a series of compressive strength of core specimen’s to correlate the rebound hammer indices and UPSV results obtained from member of existing buildings. The combined method (SONREB) was used to quality control and strength estimation of the concrete. This combined method requires short time to obtain the results, it’s a non-invasive method and it does not affect the resistance of structural elements. The best fit equation of SONREB method for the determination of concrete compressive strength is obtained through processing correlation among the data sets. Finally the investigation and comparison of experimental results of non-destructive tests and core strength with the help of statistical data obtained by testing of specimen as per recommended procedures by IS 13311:1992 and IS 516:1959 respectively. The use of the combined methods (SONREB) increases the accuracy of the estimation of the in situ concrete compressive strength.
Single step formation of biocompatible bimetallic alloy nanoparticles of gold and silver using isonicotinylhydrazide.
Manufacturing nanoparticles with controlled physicochemical properties using environment-friendly routes have potential to open new prospects for a variety of applications. Accordingly, several approaches have been established for manufacturing metal nanoparticles. Many of these approaches entail the use of hazardous chemicals and could be toxic to the environment, and cannot be used readily for biomedical applications. In the present work, we report a single step bio-friendly approach to formulate gold (Au), silver (Ag), and Au-Ag alloy nanoparticles with desired surface corona and composition using isonicotinylhydrazide (INH) as a reducing agent. INH also functioned as a stabilizing agent by enabling a surface corona around the nanoparticles. Remarkably, within a single step INH could also provide a handle in regulating the composition of Au and Ag in bimetallic systems without any additional chemical modification. The physicochemical and surface properties of the different nanoparticles thus obtained have been examined by analytical, spectroscopic and microscopic techniques. Cell cytotoxicity (release of lactate dehydrogenase), cell viability and intracellular reactive oxygen species (ROS) assays confirmed that the Au, Ag, and Au-Ag bimetallic nanoparticles prepared with INH are biocompatible. Finally, the presence of organic surface corona of INH on the nanoparticles was found to impart nanozyme activity and antimycobacterial sensitivity to the nanoparticles.