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71.
分子聚集溶液理论及其应用   总被引:1,自引:0,他引:1  
本文应用经典热力学和分子热力学方法建立了分子聚集溶液理论。该理论具有通用性;它不仅适用于非电解质溶液,而且也可应用于电解质溶液。另外,溶液的分子聚集度参数与组分浓度的相关性规律还可用来描述电解质溶液的传递性质。  相似文献   
72.
§ 1 IntroductionConsiderthefollowingnonlinearoptimizationproblem :minimizef(x)subjecttoC(x) =0 , a≤x≤b ,( 1 .1 )wheref(x) :Rn→R ,C(x) =(c1(x) ,c2 (x) ,...,cm(x) ) T:Rn→Rm aretwicecontinuouslydifferentiable,m≤n ,a ,b∈Rn.Trustregionalgorithmsareveryeffectiveforsolvingnonlinearoptimi…  相似文献   
73.
We study the conformal scalar curvature problem


where is a continuous function. We show that a necessary and sufficient condition on for this problem to have positive solutions which are arbitrarily large at is that be less than 1 on a sequence of points in which tends to .

  相似文献   

74.
利用非参数方法对上海股市周末效应的研究   总被引:11,自引:0,他引:11  
刘彤 《数理统计与管理》2003,22(1):28-32,57
本文首先利用基本统计分析和Kolmogorov -Smirnov检验发现沪市指数收益率不服从正态分布 ,随后利用了K -W检验考察周末效应的存在性 ,利用M -W检验考察周末效应的模式 ,最后利用了Levene检验来对收益率序列的方差进行分析 ,得出上海股市存在“二、五”效应的结论。并从结算制度、信息流的影响、信息披露制度等方面分析了成因。  相似文献   
75.
谢莉  雷银照 《中国物理》2007,16(9):2523-2536
The well-posedness of the initial-boundary value problem of the time-varying linear electromagnetic field in a multi-medium region is investigated. Function spaces are defined, with Faraday's law of electromagnetic induction and the initial-boundary conditions considered as constraints. Gauss's formula applied to a multi-medium region is used to derive the energy-estimating inequality. After converting the initial-boundary conditions into homogeneous ones and analysing the characteristics of an operator introduced according to the total current law, the existence, uniqueness and stability of the weak solution to the initial-boundary value problem of the time-varying linear electromagnetic field are proved.  相似文献   
76.
马慧  田淑芬  谭霞  仝殿民  樊锡君 《中国物理》2007,16(10):2973-2979
An analysis is made of the effect of Doppler broadening on gain without inversion (GWI) from different aspects in a closed lambda-type three-level system with an incoherent pump. It is shown that, regardless of the driving field being on resonance or not, for the counter- or co-propagating of the probe and driving fields (PDF), GWI does not monotonically decrease or increase with increasing Doppler width. Except for the case of counter-propagating PDF with off-resonance driving field, at a suitable Doppler width one can obtain a gain maximum value much larger than that without Doppler broadening; especially in the situation of the resonant driving field, the co-propagating geometry leads to a larger GWI. In addition, for the counter-propagating geometry, when Doppler width is larger enough, GWI oscillation occurs, and the oscillation amplitude and region increase with increasing Doppler width. These conclusions are very different from that obtained in previous investigation (Lukin {\it et al}, {\it Laser Phys.} {\bf 6} 436 (1996)).  相似文献   
77.
A novel long-lasting afterglow phosphor ZrO2:Ti is prepared by the conventional solid-stated method and their luminescent properties are investigated. A bluish white strong and broad emissive band, which is attributed to originate from the recombination of electrons trapped by F+ centers and the holes created in Valence band, is observed under 254 nm UV irradiation. The identical color long afterglow, which lasts about 1 h, is found in the ZrO2:Ti phosphor after removing the 254 nm UV light. The mechanism of the long lasting phosphorescence (LLP) has been discussed based on the thermoluminescence (TL) results. The replacement of Zr by Ti produces more anion vacancies, resulting in the enhanced photoluminescence (PL) and LLP of ZrO2:Ti sample. These results indicate that ZrO2:Ti phosphor has potential promising applications.  相似文献   
78.
We summarize our key developments in nanoimprint lithography (NIL) that employs a single layer resist lift-off process: lowering of the imprint temperature (for thermal imprint) and pressure, achieving uniform resist thickness and low residual resist layer thickness in the trenches, and eliminating metal ‘rabbit ears’ for the single-layer lift-off. In thermal NIL, our requirements for lower operating temperature and pressure motivated us to develop an alternative resist that is a viscous fluid at room temperature and cures at a lower temperature of 70 °C than the operating temperature of the conventional thermal NIL (≈200 °C). For UV NIL, we devised a method to dispense the resist onto a hydrophobic mold and use the hydrophilic substrate surface to spread the resist via surface wetting to engineer a continuous and uniform film. We also explored the use of Si(110) substrates as molds to produce features with perfectly vertical side walls, and the use of aqua regia to directly etch away rabbit ears. PACS 86.65.+h; 81.16.Nd; 81.16.Rf  相似文献   
79.
This article describes a method of electroless gold deposition on a Si(100) wafer having a silver surface as seed layer. The seed layer was firstly deposited onto the surface of an etched wafer in an acidic solution of 0.005 mol/L AgNO3+0.06 mol/LHF. The electroless gold deposition is performed by immersing the Ag-activated wafer in an electroless bath with a composition of 1.27×10-3 mol/L[AuCl4]-+2.00×10-2 mol/LNaH2PO2+8.32×10-2 mol/L NH2CH2CH2NH2 (pH = 9.0–9.5). The bath temperature is 50–70 °C. The morphology of the seed layer and the gold film were characterized by atomic force microscopy (AFM) and X-ray photoelectron spectroscopy (XPS).PACS 82.45.Mp; 81.15.Pq; 81.10.Dn  相似文献   
80.
心瓣流体动力学研究进展   总被引:2,自引:0,他引:2  
心瓣流体动力学是近年来才形成的一门新兴边缘学科分支。本文比较全面地介绍了该学科的主要研究内容、研究特点、发生发展的历史和现状,以及笔者及其同事在这方面的工作,提出并论述了对学科发展有重大影响的几个富有挑战性的问题,从而预示了学科的发展方向   相似文献   
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