In this work, varying compositions of SiO₂ micro filler were added
with the Polyvinyl Chloride (PVC) and samples have been prepared
using film casting technique. The results have been analyzed and
compared for PVC samples with (1 wt%, 3 wt%, 5 wt% and 10 wt%)
SiO2 micro filler. Mechanical characteristics such as tensile strength,
elongation at break and Young`s modulus were measured for all the
samples, where the tensile strength was increased from 8.39 Mpa for
purified PVC to 16 Mpa for 3% SiO₂/PVC composite. Also, thermal
conductivity measurement values illustrated that composite materials
have a good thermal insulation at 10 wt. %, thermal conductivity was
decreased from 0.1684 W/m.

Background: The global threat of COVID-19 outbreak and on the 11 March 2020, WHO acknowledged that the virus would likely spread to all countries across the globe and declared the coronavirus outbreak a pandemic which is the fifth pandemic since 20 century and this has brought human lives to a sudden and complete lockdown and the confirmed cases of this disease and deaths continue to rise in spite of people around the world are taking important actions to mitigate and decrease transmission and save lives. Objectives: To assess the effect of exercise and physical activity on the immunity against COVID-19. Methods: Collected electronic databases including (Medline, EMBASE, Google Scholar, PubMed and Web of Science) were searched with

ZnIn2(Se1-xTex)4 (ZIST) chalcopyrite semiconductor thin films at various contents (x = 0.0, 0.2, and 0.4) are deposited on glass and p type silicon (111) substrate to produce heterojunction solar cell by using the thermal evaporation technique at RT where the thickness of 500 nm with a vacuum of 1×10-5 mbar and a deposited rates of 5.1 nm/s. This study focuses on how differing x content effect on the factors affecting the solar cell characteristics of ZIST thin film and n-ZIST/p-Si heterojunction. X-ray diffraction XRD investigation shows that this structure of ZIST film is polycrystalline and tetragonal, with (112) preferred orientation at 2θ ≈ 27.01. Moreover, atomic force microscopy AFM is studying the external morphology of

The study included studying some of the optimum environmental conditions(temperature ,light intensity ) on the production of several green algae Scendesmus quadricauda and Chlorella vulgaris in a selected culture and municipal wastewater . The study also included the recording of growth rate ,doubling time and removal of phosphate and nitrate , maximum rate was recorded to the growth with minimum in doubling time and maximum removal rate of nitrogen-nitrate and phosor- phosphate in each selected culture and municipal wastewater in each species of green algae at 25 C? and a light intensity 380 µ E / m2 / s.

The Cu2SiO3 composite has been prepared from the binary compounds (Cu2O, and SiO2) with high purity by solid state reaction. The Cu2SiO3 thin films were deposited at room temperature on glass and Si substrates with thickness 400 nm by pulsed laser deposition method. X-ray analysis showed that the powder of Cu2SiO3 has a polycrystalline structure with monoclinic phase and preferred orientation along (111) direction at 2θ around 38.670o which related to CuO phase. While as deposited and annealed Cu2SiO3 films have amorphous structure. The morphological study revealed that the grains have granular and elliptical shape, with average diameter of 163.63 nm. The electrical properties which represent Hall effect were investigated. Hall coeffici

Fresh water resources in terms of water quality is a crucial issue worldwide. In Egypt, the Nile River is the main source of fresh water in the country and monitoring its water quality is a major task on governments and research levels. In the present case study, the physical, chemical and algal distribution in Nile River was monitored over two seasons (winter and summer) in 2019. The aims of the study were to check the seasonal variation among the different water parameters and also to check the correlations between those parameters. Water samples were collected from the Nile in Cairo governorate in EGYPT. The different physiochemical and microbiological properties in water samples were assessed. The studied parameters were included: te