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排序方式: 共有839条查询结果,搜索用时 15 毫秒
71.
Silicon - This paper examines a Junctionless quadruple gate (JLQG) MOSFET for analog and linearity distortion performance by numerically calculating transconductance and its higher order... 相似文献
72.
High Open‐Circuit Voltages in Tin‐Rich Low‐Bandgap Perovskite‐Based Planar Heterojunction Photovoltaics
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73.
In this work, the tribological behavior of micrometer and submicrometer cenosphere particulate–filled E-glass fiber–reinforced vinylester composites have been investigated on a pin-on-disc tester under dry sliding and water-lubricated sliding conditions. Three different uniform sizes of cenosphere particles (2 μm, 900 nm, 400 nm) were used as fillers in the glass fiber–reinforced vinylester composites. The weight fraction of cenosphere particles has been varied in the ranges from 5, 10, 15, to 20 wt%. The experimental results show that all of the composites exhibited lower coefficient of friction and lower wear resistance under water-lubricated sliding conditions than under dry sliding. It has been noted that the submicrometer size (400 nm) cenosphere particulates as fillers contributed significantly to improve the wear resistance. It has also been noted that 10 wt% of the cenosphere particles is the most effective in reducing the wear rate and coefficient of friction. Effects of various wear parameters such as applied normal loads, sliding speeds, particle size, and particle content on the tribological behavior were also discussed. In order to understand the wear mechanism, the morphologies of the worn surface were analyzed by means of scanning electron microscopy (SEM) for composite specimens under both dry and water-lubricated sliding conditions. 相似文献
74.
M. Pyle D. A. Bauer B. Cabrera J. Hall R. W. Schnee R. Basu?Thakur S. Yellin 《Journal of Low Temperature Physics》2012,167(5-6):1081-1086
Amplifying the phonon signal in a semiconductor dark matter detector can be accomplished by operating at high voltage bias and converting the electrostatic potential energy into Luke-Neganov phonons. This amplification method has been validated at up to |E|=40 V/cm without producing leakage in CDMS?II Ge detectors, allowing sensitivity to a benchmark WIMP with mass M χ =8 GeV/c2 and σ=1.8×10?42 cm2 (with significant sensitivity for M χ >2 GeV/c2) assuming flat electronic recoil backgrounds near threshold. Furthermore, for the first time we show that differences in Luke-Neganov gain for nuclear and electronic recoils can be used to discriminate statistically between low-energy background and a hypothetical WIMP signal by operating at two distinct voltage biases. Specifically, 99% of events have p-value <10?8 for a simulated 20?kg-day experiment with a benchmark WIMP signal with M χ =8 GeV/c2 and σ=3.3×10?41 cm2. 相似文献
75.
Sandeep Mahajan O. P. Thakur Chandra Prakash K. Sreenivas 《Bulletin of Materials Science》2011,34(7):1483-1489
A polycrystalline sample of Zr-doped barium titanate (BaTiO3) was prepared by conventional solid state reaction method. The effect of Zr (0·15) on the structural and microstructural properties of BaTiO3 was investigated by XRD and SEM. The electrical properties (dielectric, ferroelectric and impedance spectroscopy) were measured in wide range of frequency and temperature. With substitutions of Zr, the structure of BaTiO3 changes from tetragonal to rhombohedral. Lattice parameters were found to increase with substitution. The room temperature dielectric constant increases from ~ 1675 to ~ 10586 and peak dielectric constant value increases from ~ 13626 to ~ 21023 with diffuse phase transition. Impedance spectroscopy reveals the formation of grain and grain boundary in the material and found to decrease with increase in temperature. 相似文献
76.
In this work, we construct electrodes of brass to produce plasma by arc discharge and is characterized by using a movableLangmuir single probe. It is a simple w... 相似文献
77.
78.
Use of ultrasound for lipoxygenase inactivation in whole soy flour suspension was studied. Inactivation of the enzyme was influenced by the time of exposure, pH, and the amplitude of ultrasound. Exposure to cavitating 20 kHz ultrasound for 3 h at pH > 5.0 had no effect on the activity of the enzyme. However, under similar conditions, the activity decreasd by 70-85% when pH was lowered to 5.0 and 4.0, respectively. Lipoxygenase activity also decreased with increase in frequency of the ultrasound waves when pH was ≥5.0; above pH 5.0, increase in frequency did not affect the enzyme activity after an exposure of 1 h. 相似文献
79.
Using the methods of recombination and gene disruption, the effects of degUS gene in Bacillus subtilis Ki-2-132 were studied. The results showed that the gene could affect all protease-producing, competence formation, cell mobility and repression effects of glucose on protease-production. This implies that it is a pleitropic gene in Bacillus subtilis Ki-2-132. The disruption of the gene caused morphological changes and repressed the expression of aprE in vectors. 相似文献
80.
Bhanu K. Patibandla Akshita Narra Ranil DeSilva Varun Chawla Yael Vin Robert S. Brown Alexander S. Goldfarb‐Rumyantzev 《Hemodialysis international. International Symposium on Home Hemodialysis》2014,18(1):118-126
The benefits of an arteriovenous fistula (AVF) as the preferred vascular access for hemodialysis have been clearly demonstrated. However, only about 20% of patients in the United States initiate hemodialysis with an AVF. In this study, we assessed whether disparities exist in the type of first hemodialysis access placed prior to dialysis start (rather than that used at dialysis initiation), to detect whether certain disadvantaged groups might have lower likelihood of AVF placement. Study cohort of 118,767 incident hemodialysis patients ≥67 years of age (1/2005–12/2008) derived from the United States Renal Data System was linked with Medicare claims data to identify the type of initial access placed predialysis. We used logistic regression model with outcome being the initial predialysis placement of an AVF as opposed to an arteriovenous graft or a central venous catheter. Increasing age, female sex, black race, lower body mass index, urban location, certain comorbidities, and shorter pre–end‐stage renal disease nephrology care are all associated with a significantly lower likelihood of AVF placement as initial access predialysis. Our study suggests the presence of significant disparities in the placement of an AVF as initial hemodialysis vascular access. We suggest that additional attention should be paid to these patient groups to improve disparities by patient education, earlier referral, and close follow‐up. 相似文献