The activation energy and optical band gap of different regions (p-type) polysilicon have been measured. Both microscopic studies and current-voltage characteristics of diodes prepared on different surface regions were carried out. Comparison of diodes parameters and microscopic studies indicate that the type of angles between boundaries has a significant effect on diodes parameters while the boundary lengths per unit area has less effect. The mechanism of Al-interaction with grain boundaries and their intersecting points at different temperature were also studies. The X-ray fluorescence spectrometry has been used for detection of diffused A1%.
The finite element method has been used in this paper to investigate the behavior of precast reinforced concrete dapped-ends beams (DEBs) numerically. A parametric investigation was performed on an experimental specimen tested by a previous researcher to show the effect of numerous parameters on the strength and behavior of RC dapped-end beams. Reinforcement details and steel arrangement, the influence of concrete compressive strength, the effect of inclined load, and the effect of support settlement on the strength of dapped-ends beams are examples of such parameters. The results revealed that the dapped-end reinforcement arrangement greatly affects the behavior of dapped end beam. The failure load decreases by 25% when
... Show MoreTransforming the common normal distribution through the generated Kummer Beta model to the Kummer Beta Generalized Normal Distribution (KBGND) had been achieved. Then, estimating the distribution parameters and hazard function using the MLE method, and improving these estimations by employing the genetic algorithm. Simulation is used by assuming a number of models and different sample sizes. The main finding was that the common maximum likelihood (MLE) method is the best in estimating the parameters of the Kummer Beta Generalized Normal Distribution (KBGND) compared to the common maximum likelihood according to Mean Squares Error (MSE) and Mean squares Error Integral (IMSE) criteria in estimating the hazard function. While the pr
... Show MoreLaser skin wound soldering offers many distinct advantages over conventional closure and laser welding techniques. Objective : to compare the histological effects of human skin wound soldering using 50 % human albumin solder and compound charcoal photosensitiser with 980 nm diode laser acting in various modes of action and parameters. Study Design/Materials and Methods: In this in vitro experimental study , Multiple 3-4 cm long full thickness incisions in a specimen of human skin were soldered using a 4 mm spot diameter beam of 980 nm diode laser(at different laser parameters and modes of action) with 50 % human albumin solder mixed with the compound charcoal at 5 % W/V concentration .After obtaining a successful wound soldering , the wo
... Show MoreFresh 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
... Show MoreDiabetic kidney disease is an illness of the glomerulus that interferes with the glomerular filtration barrier (GFB), which is worked to enable kidney to selective purification of water and solutes in addition to limiting the movement of large macromolecules such as albumin. In the glomerular endothelium, mesangial cells, foot cells, and the brush border of the proximal tubules, ACE-2 is expressed and that the kidneys represent the highest-expressing region of this enzyme. Thus, the current study aimed to evaluate ACE-2 level in this case compared to healthy condition. The study Conducted with 120 male and female ranging in age (30-65) years old. Ninety patients with type 2 diabetes subdivided into three groups on the basis of A
... Show MoreThe effect of considering the third dimension in mass concrete members on its cracking behavior is investigated in this study. The investigation includes thermal and structural analyses of mass concrete structures. From thermal analysis, the actual temperature distribution throughout the mass concrete body was obtained due to the generation of heat as a result of cement hydration in
addition to the ambient circumstances. This was performed via solving the differential equations of heat conduction and convection using the finite element method. The finite element method was also implemented in the structural analysis adopting the concept of initial strain problem. Drying shrinkage volume changes were calculated using the procedure sug
In this work, MWCNT in the epoxy can be prepared at room temperature and thickness (1mm) at different concentration of CNTs powder. Optical properties of multi-walled carbon nanotubes (CNTs) reinforced epoxy have been measured in the range of (300-800)nm. The electronic transition in pure epoxy and CNT/epoxy indicated direct allowed transition. Also, it is found that the energy gap of epoxy is 4.1eV and this value decreased within range of (4.1-3.5)eV when the concentration of CNT powder increased from (0.001-0.1)% respectively.
The optical constants which include (the refractive index (n), the extinction coefficient (k), real (ε1) and imaginarily (ε2) part of dielectric constant calculated in the of (300-800)nm at different concent
The dielectric properties of polyvinyl chloride (PVC)-MnCl2 composite were studied by using the impedance technique. The measurements were carried out as a function of frequency in the range from 10 Hz to 13 MHz and temperature range from 27oC to 55oC. Using a composite of 20 wt. % MnCl2 by weight, it was found that the dielectric constants and the dielectric loss of the prepared films increase with the increasing temperature at law frequency and the enhancement of the ionic conduction which is confirmed by the increase the of AC. conductivity and the decrease of the activation energy of the conduction mechanism at high applied frequency. The observed relaxation and polarization effects of composite a
... Show MoreThis study has been conducted to examin the effect of sodium propionate at different level of 0.03,0.06,0.10% on the number of bacteria and mold and to extend the storage life of laboratory processed biscuit. The results indicated that the use of 0.10% sodium propionate prolonged the storage peroid until the third month, while the use of 0.20% sodium propionate showed no growth of bacteria up to six month of storage, three types of bacteria has been isolated from processed biscuit, namely, Staphylococcus aureus, Bacillus cereus, Esherichia coli. using 0.10% sodium propionate showed no growth of mold up to three month of storage ,while using of 0.15 % and 0.20% sodium propionate prevent the growth
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