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The conductivities of polyaniline magnetite (PANI/Fe3O4) nanocomposites prepared by sol-gel method were measured by standard van der Pauw DC 4-point probe method. PANI/Fe3O4 conductivity was measured as a function of wt % (5, 10, 15, 20 and 25 wt %) of Fe3O4 nanoparticles. It was observed that the conductivity of polyaniline containing certain percentage of Fe3O4 nanoparticles is slightly lower than the bulk PANI nanotubes and drastically decreases with increase of wt % Fe3O4 nanoparticles. The high conductivities of PANI/ Fe3O4 nanocomposites was observed due to high concentration of dopant (oxidants) used in the polymerization process and the optimization of these composites allows this being use as a parameter for the production of nanofibers. Fourier transform infrared spectra, field emission scanning electron microscope, X-ray diffraction and ultraviolet-visible absorption spectra are used to characterize the phase structure, morphologies and functional group of the PANI/Fe3O4 composites samples. Fourier transform infrared analysis indicates the presence of PANI containing Fe3O4 nanoparticles and the field emission scanning electron microscope (FESEM) results has proven that the formation of nanofibers in the PANI/Fe3O4 nanocomposites. The crystalline phase of PANI/Fe3O4 nanocomposites studied by X-ray diffraction indicated that the Fe3O4 nanoparticles was present in the PANI matrices.

The gas exchange characteristics and photosynthetic pigments of a plant can be affected by the amount of light received by the plant. The objective of this research is to investigate the effect of light intensity on the gas exchange characteristics and total pigment content TPC of sun and shade leaves of Psidium guajava. Sun and shade leaves were studied, and their photosynthetic light response characteristics including light saturation point (LSP), light compensation point (LCP) and apparent quantum yield were estimated. Carotenoids (Car) and chlorophyll (Chl) contents were quantified spectrophotometrically, while total anthocyanin content (TAC) was determined using the pH differential method. The result of this study shows that high light intensity influence gas exchange, carotenoid content and total anthocyanin content while low light intensity influence chlorophyll content especially chlorophyll b of the studied plant. As the light intensity increases, Amax, light saturation point and light compensation point increases. There are significant differences between the photosynthetic light response characteristics and total pigment content of sun and shade leaves (P<0.05). The result leads to a conclusion that sun leaves of Psidium guajava contribute the greatest photosynthetic capacity to the plant than shade leaves. The high carotenoid and total anthocyanin contents of sun leaves provides photo protection to the plant.

Gamma ray shielding properties of borate glass samples containing oxides of lead and zinc are prepared by melt and quench technique and evaluated theoretically using XCOM computer software for gamma ray shielding properties. However, gamma ray shielding properties are discussed in terms of various calculated parameters such as half value layer, mean free path and mass attenuation coefficient. The calculated parameters are compared by the author with conventional shielding material concrete. FTIR studies are undertaken to investigate the various structural groups present in the prepared system. Furthermore, it was observed that the glass sample S1 posses minimum HVL value and maximum mass attenuation coefficient, It has been inferred that addition of lead improve the gamma ray shielding properties and simultaneously decrease the rigidity of the glass systems due to formation of non bridging oxygen. Gamma ray shielding properties of our glass systems have been compared with standard nuclear radiation shielding concrete.

The demand of concrete have been increases on a daily bases which consume a lot of natural resource such as sand and gravel,  there is an immediate need for finding suitable alternative which can be used to replace sand partially with another materials with high proportion . Ceramic waste is one of the strongest research areas that include the activity of replacement in all the sides of construction materials. This research aims to improve the performance of concrete using ceramic waste, and demonstrate the performance of mechanical properties to the concrete with partial replacement of sand by using waste porcelain. For these, we analyzed the mechanical properties of the concrete such as compressive strength, split tensile and flexural strength, the specimen were measured based on 10% ,20% ,30% ,40%, and 50% weight ratio of replace sand with waste porcelain at different time under water for 7 days , 28 days , 60 days . The optimum consideration were given to mechanical properties of the concrete, at different amount of ceramic waste as sand.

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