半导体瞬态问题的修正迎风有限体积格式

半导体器件的瞬时状态由包含三个拟线性偏微分方程所组成的方程组的初边值问题来描述.其中电子位势方程足椭圆型的,电子和空穴浓度方程是对流扩散型的.对电子位势方程采用一次元有限体积法米逼近,对电子浓度和空穴浓度方程采用修正的迎风有限体积方法来逼近,并进行详细的理论分析,关于位势得到O(h Δt)阶的H1模误差估计结果,关于浓度得到O(h2 Δt)阶的L2模误差估计结果.最后,给出数值例子.     

Study on multi-objective optimization of flow allocation in a multi-commodity stochastic-flow network with unreliable nodes

A long distance transportation problem was abstracted to a resource flow allocation problem upon a stochastic-flow network with unreliable nodes. The objectives were the probability that transmission was successful and transportation cost. In order to solve constructed model, a multi-objective genetic algorithm was propounded. Tested by examples, the algorithm well solved the flow allocation problem in a stochastic-flow network.     

Influence of ammoniating temperature on Co-catalyzed GaN nanowires

GaN nanowires (NWS) were synthesized at different temperatures by ammoniating Ga₂O₃/Co films deposited on Si (111) substrate. X-ray diffraction (XRD), scanning electron microscopy (SEM), high resolution transmission electron microscope (HRTEM), Fourier transformed infrared spectra (FTIR) and photoluminence (PL) spectra were used to characterize the influences of the ammoniating temperature on the morphology, crystallinity and optical properties of GaN NWS. Our results indicate that the samples are all of wurtzite structure and also show that the GaN NWS ammoniated at 950 °C have the best morphology and crystallinity with a single-crystalline structure, and at this temperature the PL spectrum with the strongest ultraviolet (UV) peak is observed. PACS 61.46.-w; 71.55.Eq; 81.15.Cd; 81.07.-b; 61.10.Nz     

量子纠错码的等价和保距同构

研究了量子纠错码的等价性和保距同构,推广了Bogart等人的一些概念,并给出若干基本定理,这些定理对进一步研究量子码的等价性和保距同构是非常有用的.在此基础上构造出一个反例,证明了在量子情形下,MacWmiams的一个重要定理不成立.     

Theoretical study on the mechanism of the reaction for alkene hydroaminations catalyzed by chiral aldehyde

Alkene hydroamination catalyzed by chiral aldehyde relying only on temporary intramolecularity is a new concept reaction. In this article, the reaction mechanism was investigated using density functional theory. The calculation results show that: (1) The reaction can be divided into two parts. The first part is a dehydration process involving a hemiaminal formation. The nitrone catalyst forms through rapid intermolecular nucleophilic addition of benzylhydroxylamine to chiral aldehyde precatalyst. The second part is a catalytic cycle, which involves an aminal formation—hydroamination—ring opening—product release process. (2) There are four enantioselective pathways related to the products of S and R configurations. Enantioselectivity is attributed to the different forming ways of a planar five‐membered ring. The preferred pathways for the S‐configuration product ( S3 ) and R‐configuration product ( R3 ) are confirmed. © 2013 Wiley Periodicals, Inc.     

Nonexistence and Existence of Multiple Positive Solutions for Superlinear Three-point Boundary Value Problems via Index Theory

This paper discusses both the nonexistence of positive solutions for second-order three-point boundary value problems when the nonlinear term f（t, x, y） is superlinear in y at y = 0 and the existence of multiple positive solutions for second-order three-point boundary value problems when the nonlinear term f（t, x,y） is superlinear in x at ＋∞.     

The FT-Raman Study of Reaction of 4-Aminophenyl Disulfide and Epoxy on Silver Surface

4-Aminophenyl disulfide (APDS) can cleave and be chemisorbed on etched silver foil to form an assembled film. The film can serve as coupling agent to form an inter phase between silver and epoxy bulk. The coupling action and mechanism of APDS between silver and epoxy polymer were characterized by Fourier transform surface-enhanced Raman scattering spectroscopy.     

Binding Numbers and Connected Factors

In this paper, we obtain some sufficient conditions based on binding number for a graph to have a connected factor with degree restrictions. Let α and k be positive integers with α + k ≥ 4. Let G be a connected graph with a spanning subgraph F, each component of which has order at least α. We show that if the binding number of G is greater than (α k − α)/(α k − α −1) (k ≥ 2) and α/(α −2) (k = 1) then G has a connected subgraph which has F and in which every vertex v has degree at most deg _F (v) + k. From the result, we derive various sufficient conditions for a graph to have a connected [a, b]-factor.     

广义簇合物在非均匀几率密度下的生长

采用族合物生长的自调整模型，并用扩散粒子的非均匀几率密度场模拟了簇合物和扩散粒子之间的非均匀相互作用势场,研究了广义簇合物在非均匀场下的生长形态，考察了深度因子α、粘附参数t等对簇合物生长形态及对非均匀场的影响，结果表明，非均匀场的性质是决定族合物生长几何形态的主要因素，深度因子α决定了簇合物中生长形态的紧密程度，粘附参数t决定了致密程度，α、t等参数对场的作用有一定的影响     

肼黄与牛血清白蛋白相互作用的光谱研究

本文用荧光光谱法和紫外-可见吸收光谱法研究了肼黄与牛血清白蛋白(BSA)结合反应的光谱行为,发现肼黄因对BSA有较强的荧光猝灭作用,且肼黄的紫外吸收光谱和BSA的荧光发射光谱有一定程度的重叠,据此得出了其结合反应的结合常数、结合位点数和基本热力学参数等,并研究了二者的相互作用机理。