The effect of gamma ırradiation on electrical characteristics of au/polyvinyl alcohol (co, zn-doped)/n-si schottky barrier diodes

WOS: 000280536400076To show the effect of gamma radiation, Au/Polyvinyl Alcohol (Co, Zn-doped)/n-Si Schottky barrier diodes (SBDs) were exposed to (60)Co gamma-ray source at room temperature. These structures were investigated by using current-voltage (I-V), capacitance-voltage (C-V), and conductance-voltage (G/omega-V) measurement methods before and after irradiation. The C-V and G omega-V measurements were carried out at 1 MHz. The density of interface states (N(ss)) as a function of E(c)-E(ss) was obtained from the forward bias I-V data by taking into account the bias dependence effective barrier height (Phi(e)) and series resistance (R(s)) of device at room temperature. Experimental results show that the values of ideality factor (n), R(s) and N(ss) increased after gamma irradiation. It was found to degrade the reverse leakage current with radiation whereas its effect on the forward I-V characteristics was negligible. The results show that main effect of the radiation is the generation of N(ss) with energy level within the forbidden band gap of Si between polymer and semiconductor. In addition, the values of R(s) were determined from Cheung's method, and it was seen that these values increased with radiation effect. As seen I-V and C-V characteristics, the main electrical parameters such as ideality factor (n), R(s), N(ss) were strongly influenced with the presence of radiation. (C) 2010 Wiley Periodicals, Inc. J Appl Polym Sci 118: 596-603, 201

The Effect of Alendronate and Calcitonin Treatments on Bone Mineral Density and Quality of Life in Women With Postmenopausal Osteoporosis

The aim of this study was to compare the effect of alendronate and calcitonin treatments on bone mineral density (BMD) and quality of life of women with postmenopausal osteoporosis. One hundred ninety-three patients were randomly assigned to two groups: 93 patients received daily doses of 10 mg alendronate and calcium 1000 mg, and 98 patients used intranasal salmon calcitonin (sCt) at a dosage of 200 IU/day and they also received daily doses of 1000 mg calcium supplements. DXA was used for the measurement of BMD of the lumbar spine and proximal femur before and after the study period. SF-36 was used as a measure of health-related quality of life. At the end of the treatment, ALN produced significant increases in BMD at the lumbar spine (p< 0.001), femur neck (p<0.05), trochanteric region (p<0.001) and at the Ward triangle (p<0.05). In contrast, intranasal sCt treatment resulted in a significant bone loss in the femur neck (p<0.01) and Ward triangle (p<0.05), and only a significant increase in BMD of the lumbar spine was observed with calcitonin treatment(p< 0.05). Quality of life as assessed by SF-36 improved significantly in both groups(p<0.05). In conclusion, alendronate seemed to be more effective than calcitonin, increasing both spinal and femoral BMD, for the treatment of postmenopausal osteoporosis. Both treatments were found to be effective for the improvement of quality of life