Throughout the centuries, several incidents of mercury toxicity have been reported. Mercury is found in many industries such as battery, thermometer and barometer manufacturing, in the agricultural industry is used in fungicides and in medicine, mercury is used in dental amalgams. An important mechanism involved in cellular injury is induced by exposure to different forms of mercury involves in the induction of oxidative stress. This study was conducted on non-smoker, male working in a chloroalkali plant for different periods, all workers were not suffering from chronic disease. Healthy non-smoker males that are not exposed, matched age were used as controls(C), workers aged (22-61) years, they were divided into three groups: G1: workers with exposed period less than 10 years, G1 < 10 years. G2: workers with exposed period (10-19) years . G3: included workers with exposed period more than 19 years, G3 > 19 years. The result we had through examining the different parameters led us to add another group which included individuals with high mercury levels regardless the occupation period, in this group we found high significant changes in the defense system parameters that we measured. This study showed an elevation in MDA levels in all workers group, specially those with high level mercury , which were 9.31, 12.78, 12.99, 14.73, and 18.11nmol/dl for C, G1, G2 , G3 ,and high level mercury workers respectively . No alteration was found in SOD activity in erythrocyte (0.67, 0.73, 0.72, and 0.77 U/g.Hb) for C, G1, G2 and G3 respectively. There were highly significant decrease in catalase activity (P < 0.001) in erythrocyte of all worker groups compared to normal control. The values were (1.5, 0.8, 0.88, 0.815 and 0.45 U/gm/Hb) for C, G1, G2, G3 and G4 respectively. While there were high elevation in glutathione S-transferase activity in worker groups compared to control (P < 0.001) and values were (1.85, 2.589, 2.441, 2.776 and 3.2 U/gm.Hb) for C, G1, G2 and G3 respectively.
In this research study theory to find the stress and emotion gases in the glass as a result of exposure to pulses of the laser beam has been the study using vehicles three major on-system axes cylindrical (r, 0, z), where I took three models of glass silica glass soda glass fused and shedtwo types of lasers where the study showed that the thermal stresses and emotions ...
The study of the future of the international system currently appears, according to scientific data and existing facts in light of the emergence of international actors from non-states and international informal institutions, to be heading towards a non-polarity system and this trend is fueled by many variables to reduce polarity, and it is expected in the future that the international system will turn into a non-polarity.
The mechanical design of elevator elements is always performed by international standards. The engineer selects the appropriate elements of elevator according to catalogues without knowing scientific details. Therefore, a theoretical analysis is achieved at two operating conditions for guide rails (1) safety gear operation, and (2) running condition with the loads unevenly distributed on the elevator car. The guide rail is considered a continuous beam with variable supports. Then the British code is listed showing the equations used in it.
The theoretical equations showed that guide rails are never subjected to stress in simultaneous combined buckling and bending in the plane, where the bending moment is exerted. It is always a c
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A numerical computation for determination transmission coefficient and resonant tunneling energies of multibarriers heterostructure has been investigated. Also, we have considered GaN/Al0.3Ga0.7N superlattice system to estimate the probability of resonance at specific energy values, which are less than the potential barrier height. The transmission coefficient is determined by using the transfer matrix method and accordingly the resonant energies are obtained from the T(E) relation. The effects of both well width and number of barriers (N) are observed and discussed. The numbers of resonant tunneling peaks are generally increasing and they become sharper with the increasing of N. The resonant tunneling levels are shifted inside the well by
... Show MoreA numerical computation for determination transmission coefficient and resonant tunneling energies of multibarriers heterostructure has been investigated. Also, we have considered GaN/Al0.3Ga0.7N superlattice system to estimate the probability of resonance at specific energy values, which are less than the potential barrier height. The transmission coefficient is determined by using the transfer matrix method and accordingly the resonant energies are obtained from the T(E) relation. The effects of both well width and number of barriers (N) are observed and discussed. The numbers of resonant tunneling peaks are generally increasing and they become sharper with the increasing of N. The resonant tunneling levels are sh
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In this study, generation of elliptical gears with different teeth profiles of crowned involute, double circular arc (DCA), and combined (crowned involute with DCA) has been developed. The resulting mathematical equations have been computerized and feed to CNC end mill machine to manufacture elliptical gear models with different profiles. These models are investigated in plane polariscope to show the resulting stresses under certain load. Comparison of photo-elastic stress results shows that combined elliptical gears with DCA side as a loaded side have a minimum resulting contact stress with a reduction percentage of 40% compare with contact stresses in counterpart elliptical gear of involute profile (which is commonly u
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