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排序方式: 共有186条查询结果,搜索用时 31 毫秒
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Madhab Chandra Tripathy Debasmita Mondal Karabi Biswas Siddhartha Sen 《International Journal of Circuit Theory and Applications》2015,43(6):776-792
The present work reports the realization of an analog fractional‐order phase‐locked loop (FPLL) using a fractional capacitor. The expressions for bandwidth, capture range, and lock range of the FPLL have been derived analytically and then compared with the experimental observations using LM565 IC. It has been observed that bandwidth and capture range can be extended by using FPLL. It has also been found that FPLL can provide faster response and lower phase error at the time of switching compared to its integer‐order counterpart. Copyright © 2014 John Wiley & Sons, Ltd. 相似文献
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T Takagi M Hashiguchi RI Mahato H Tokuda Y Takakura M Hashida 《Canadian Metallurgical Quarterly》1998,245(3):729-733
Lamina-associated polypeptide (LAP)2, which directly interacts with B-type lamins and chromosomes, is an integral membrane protein specifically distributed along the inner nuclear membrane of the nuclear envelope. Multiple regions of its large nucleoplasmic domain promote this localization, including the first (residues 1-296) and the second (residues 298-409) halves of the LAP2 N terminus. The second half is involved in LAP2 association with the nuclear lamina [Furukawa, K., Panté, N., Aebi, U. & Gerace, L. (1995) EMBO J. 14, 1626-1636]. In this study to further define its role, we examined which domain of B-type lamin interacts with LAP2 by means of a binding assay with bacterially expressed proteins and a yeast two-hybrid system. We found that amino acids in the region of residues 78-258 of the lamin B1 rod domain directly bound with LAP2. The data suggest that LAP2 may modulate the assembly of nuclear lamins. 相似文献
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Sojoodi Amir Hossein Salimi Beni Majid Khunjush Farshad 《The Journal of supercomputing》2021,77(3):3165-3192
The Journal of Supercomputing - During recent years, big data explosion and the increase in main memory capacity, on the one hand, and the need for faster data processing, on the other hand, have... 相似文献
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A new regular ABA-type triblock copolymer has been synthesized by polycondensation of the acid chloride of carboxy-terminated butadience-acrylonitrile rubber (CTBN) with hydroxyterminated polyethylene isophthalate (PEI) oligomer. This block copolymer was characterized by elemental (nitrogen) analysis, vapor pressure osmometry, viscometry, and IR and NMR spectroscopy. Quantitative estimation of block segments has been carried out by measuring the area under peaks assigned to various protons in the NMR spectrum of the polymer. NMR spectral analysis has been found to agree well with the nitrogen analysis of the polymer. The solubility and solution viscosity behavior of the polymer has also been studied. 相似文献
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Ashwani Kumar Tiwari Prasoon Kumar Singh Mukesh Kumar Mahato 《Mine Water and the Environment》2017,36(4):532-541
This study was carried out in the West Bokaro coalfield area of the Jharkhand state of India to assess water quality for drinking and domestic purposes. Thirty mine water samples were collected from opencast and underground mines, and concentrations of Al, As, Ba, Cr, Cu, Fe, Mn, Ni, Se, and Zn were determined using ICP-MS. Spatial distribution maps were prepared using GIS software so that the quality of the mine water could be easily understood. Metal concentrations were higher in the pre-monsoon season than in the post-monsoon season, irrespective of location, but there were more significant seasonal variations in the opencast mine water than in the underground mine water. The concentrations of Al, Ba, Fe, Mn, and Ni exceeded the desirable as well as the permissible drinking water limits in both seasons. The quality of the surface water as well as the groundwater in the region may be adversely affected by the high metal concentrations in this mine water. 相似文献
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Journal of Materials Science - We report upon synthesis of stable chains of magnetically aligned zero-valent α-Fe nanoparticles and investigation of their magnetization reversal mechanism. The... 相似文献
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T. Ahmadi A. Monshi V. Mortazavi M.H. Fathi S. Sharifi B. Hashemi Beni A. Moghare Abed M. Kheradmandfard A. Sharifnabi 《Ceramics International》2014
Nanosized hydroxyapatite (HA) powders exhibit a greater surface area than coarser crystals and are expected to show an improved bioactivity. In addition, properties of HA can be tailored over a wide range by incorporating different ions into HA lattice. The aim of this study was to prepare and characterize silicon and magnesium co-doped fluorapatite (Si–Mg–FA) with a chemical composition of Ca9.5Mg0.5 (PO4)5.5(SiO4)0.5F2 by the high-energy ball milling method. Characterization techniques such as X-ray diffraction analysis (XRD), Fourier transformed infrared spectroscopy (FTIR), energy dispersive X-ray spectroscopy (EDX) and transmission electron microscopy (TEM) were utilized to investigate the structural properties of the obtained powders. Dissolution behavior was evaluated in simulated body fluid (SBF) and physiological normal saline solution at 37 °C for up to 28 days. The results of XRD and FTIR showed that nanocrystalline single-phase Si–Mg–FA powders were synthesized after 12 h of milling. In addition, incorporation of magnesium and silicon into fluorapatite lattice decreased the crystallite size from 53 nm to 40 nm and increased the lattice strain from 0.220% to 0.296%. Dissolution studies revealed that Si–Mg–FA in comparison to fluorapatite (FA), releases more Ca, P and Mg ions into SBF during immersion. 175 ppm Ca, 33.5 ppm P and 48 ppm Mg were detected in the SBF containing Si–Mg–FA after 7days of immersion, while for FA, it was 75 ppm Ca, 21.5 ppm P and 29 ppm Mg. Release of these ions could improve the bioactivity of the obtained nanopowder. It could be concluded that the prepared nanopowders have structural properties such as crystallite size (~40 nm), crystallinity degree (~40%) and chemical composition similar to biological apatite. Therefore, prepared Si–Mg–FA nanopowders are expected to be appropriate candidates for bone substitution materials and also as a phase in polymer or ceramic-based composites for bone regeneration in tissue engineering applications. 相似文献