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排序方式: 共有137条查询结果,搜索用时 15 毫秒
1.
Mathematical Programming - In this paper, we study the lower iteration complexity bounds for finding the saddle point of a strongly convex and strongly concave saddle point problem: $$\min _x\max... 相似文献
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Xinhuan Feng Lei Sun Yange Liu Lingyun Xiong Shuzhong Yuan Guiyun Kai Xiaoyi Dong 《Optical and Quantum Electronics》2004,36(10):919-926
A simple actively mode-locked fiber ring laser is proposed and successfully demonstrated to generate dual-wavelength picosecond pulses with close wavelength spacing using one Bragg grating in standard single-mode fiber. The proposed laser can be made to operate in stable dual-wavelength at room temperature, due to the birefringence characteristic of the FBG induced by transverse strain. Transverse strain loading on the FBG allows the wavelength spacing to be controlled. Generation of stable dual-wavelength pulses with a pulsewidth of 212–234 ps and a tunable wavelength separation from 0.2 to 0.44 nm at a pulse rate of 1.05 GHz was demonstrated. 相似文献
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恒电流库仑法测定基准试剂三氧化二砷的含量 总被引:2,自引:0,他引:2
用恒电流库仑法测定基准试剂三氧化二砷的含量,以恒电流通过含有碘化钾,基准试剂三氧化二砷试样的弱碱性水溶液,利用工作电极铂阳极上电生滴定剂I2与亚砷酸盐定量反应,以死停终点法确定滴定终点,测量出电解电流和电解时间,根据法拉第电解定律并利用EXCEL计算出基准试剂三氧化二砷的含量。方法的回收率为100%。 相似文献
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氯磺化聚乙烯的γ—辐射交联 总被引:2,自引:0,他引:2
氯磺化聚乙烯(简称CSM)由于存在SO_2Cl基团很容易通过金属氧化物进行化学交联,但至今未见其辐射交联的详细报道.本文探讨氯含量对CSM辐射交联的影响. 所用CSM系吉林化工公司产品:20型(含氯量29~33%,下同),40型(33~37%)和30型(40~45%).将CSM和防老D按一定比例混炼均匀,再在140℃左右热压成形.试样用3.33×10~(15)Bg ~(60)Co于室温限量空气下进行辐照.辐照过的试样于80℃处理2小时以消除俘陷自由基.在氮气保护下先后用二甲苯和无水乙醇,加热回流48小时和8小时,测定凝胶含量. 相似文献
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Enhanced nonlinearity in photonic crystal fiber by germanium doping in the core region 总被引:2,自引:0,他引:2
Germanium doping in silica can be used as a method for nonlinearity enhancement.Properties of the enhanced nonlinearity in photonic crystal fiber(PCF)with a GeO2-doped core are investigated theoretically by using all-vector finite element method.Numerical result shows that the nonlinear coefficient of PCF is greatly enhanced with increasing doping concentration,furthermore,optimal radius of the doped region should be considered for the desired operating wavelength. 相似文献
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Wang Z Kai G Liu Y Liu J Zhang C Sun T Wang C Zhang W Yuan S Dong X 《Optics letters》2005,30(19):2542-2544
Coupling characteristics of dual-core photonic bandgap fibers with triangular photonic crystal cladding are investigated by use of a vector plane-wave expansion method and a vector finite-element method. We demonstrate the eigenmodes and the coupling length for two orthogonal polarizations. A decoupling phenomenon is found at a certain wavelength in this fiber configuration. The decoupling effect is attributed to the effect of surface modes on the eigenmodes. The decoupling wavelength decreases as the ratio of core radius to cladding air-hole pitch increases from 1.05 to 1.15. 相似文献
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Meili Qu Qiying Lv Bing Yang Weide Zhang Jiaqi Zhang Shuzhong Zhan Jianshan Ye 《Electroanalysis》2010,22(4):375-378
Supported bilayer lipid membrane (s‐BLM) containing one‐dimensional compound 1, TCNQ‐based (TCNQ=7,7,8,8‐tetracyanoquinodimethane) organometallic compound {(Cu2(μ‐Cl)(μ‐dppm)2)(μ2‐TCNQ)}∞, was prepared and characterized on the self‐assembled monolayer (SAM) of 1‐octadecylmercaptan (C18H37SH) deposited onto Au electrode. Cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS) results showed that the compound 1, dotted inside s‐BLM, can act as mediator for electron transfer across the membrane. Two redox peaks and the charge‐transfer resistance of 400 kΩ were observed for compound 1 inside s‐BLM. The mechanism of the electron transfer across s‐BLM by TCNQ is by electron hopping while TCNQ‐based organometallic compound is by conducting. Further conclusion drawn from this finding is that the TCNQ‐based organometallic compound embedded inside s‐BLM exhibits excellent electron transfer ability than that of free TCNQ. This opens a new path for the development of s‐BLM sensor and/or biosensor by incorporation with TCNQ‐based organometallic compounds. 相似文献