闭排队网络中性能势与无穷小实现因子之间的关系

In this paper,the concept of the infinitesimal realization factor is extended to the parameter-dependent performance functions in closed queueing networks. Then the concepts of realization matrix (its elements are called realization factors) and performance potential are introduced,and the relations between infinitesimal realization factors and these two quantities are discussed. This provides a united framework for both IPA and non IPA approaches. Finally,another physical meaning of the service rate is given.     

生物小分子与铜锌超氧化物歧化酶相互作用的波谱学研究及其应用

本工作以ESR和NMR为主要手段,并结合其它生化方法,考察了氨基酸、核酸碱基、糖等生命基本物质,和抗坏血酸等生命必需物质与钢锌超氧化物歧化酶的相互作用,实验观测到氨基酸、核酸碱基和抗坏血酸在水溶液中可以与酶中的Cu²⁺作用而使其脱离活性部位,以小分子络合物形式游离在溶液中,同时使酶失活,脱离活性部位的Cu²⁺的比例和酶的失活程度取决于小分子配体的加入量及其与Cu²⁺的络合能力。此外,首次尝试使用ESR方法,并借助氨基酸与酶的作用,考察了铜锌超氧化物歧化酶在盐酸胍变性和热变性过程中的构象变化行为,结果表明这一方法是直观而有效的。     

关于NF-环的构造

研究了无限的ＮＦ－环及有限的ＮＦ－环，并且给出了有限ＮＦ－环的构造．     

Hypersurface with Constant Main Curvature Symmetric Functions

ＨｙｐｅｒｓｕｒｆａｃｅｗｉｔｈＣｏｎｓｔａｎｔＭａｉｎＣｕｒｖａｔｕｒｅＳｙｍｍｅｔｒｉｃＦｕｎｃｔｉｏｎｓ￥ＷｕＢａｏｑｉａｎｇ；ＳｏｎｇＨｏｎｇｚａｏ（ＸｕｚｈｏｕＴｅａｃｈｅｒｓＣｏｌｌｅｇｅ，２２１００９）（ＨｅｎａｎＵｎｉｖｅｒｓｉｔｙ，...     

Some integral inequalities inN independent variables

Some new linear and nonlinear integral inequalities of Volterra-type inn independent variables are established. They improve and contain the main results of A. Corduneanu^[7] which in turn extend a number of known results in the literature. An application to certain initial value problem of partial differential equation is also indicated.     

横向位移双曝光散斑图维纳谱的信息分布

讨论了横向位移双曝光散斑图维纳谱的信息分布，并由此导出杨氏纹图的一般表达式。讨论了条纹可见度与应变，面内转动，照明光束直径与条纹图图空间坐标的关系，指出了在条纹可见度影响下最大可见条纹数目。还讨论了散斑衬比与衍射晕的关系。     

在BBO中产生217.3-2 21.4nm高功率和频输出

用Q-YAG激光的三次谐波(355nm)与调谐的Rh·6G染料激光在β-BaB2O4(BBO)晶体中和频,获得217.3～221.4nm连续调谐输出,和频输出的最大能量为250μJ,转换效率为11%.我们还讨论了获取最大和频输出能量的一些实验条件.     

Single-molecule single crystals

Various approaches to the preparation and verification of single-molecule single crystals are discussed for polyethylene and poly (oxyethylene). Analytic tools are electron microscopy, electron diffraction, and differential scanning calorimetry. The main difficulty in producing a single-molecule single crystal is to keep crystals from joining during growth.     

Influence of preparation methods on structure and properties of PA6/PA66 blends: A comparison of melt‐mixing and in situ blending

The blends composed of polyamide 6 (PA6) and polyamide 66 (PA66) were obtained using two different preparation methods, one of which was the melt‐mixing through a twin‐screw extruder and the subsequent injection molding; and the other, the in situ blending through anionic polymerization of ε‐caprolactam in the presence of PA66. For the former, there existed a remarkable improvement in toughness but a drastic drop in strength and modulus; however, for the latter, a reverse but less significant trend of mechanical properties change appeared. Various characterizations were conducted, including the analyses of crystalline morphology, crystallographic form, and crystallization and melting behaviors using polarized optical microscopy (POM), wide‐angle X‐ray diffraction (WAXD), and differential scanning calorimetry (DSC), respectively; observation of morphology of fractured surface with scanning electron microscope (SEM); measurement of glass transition through dynamic mechanical analysis (DMA); and the intermolecular interaction as well as the interchange reaction between the two components by Fourier transform infrared spectrometry (FT‐IR) and ¹³C solution NMR. The presence and absence of interchange reaction was verified for the in situ and melt‐mixed blends, respectively. It is believed that the transreaction resulted in a drop in glass transition temperature (T_g) for the in situ blends, contrary to an increase of T_g with increasing PA66 content for the melt‐mixed ones. And the two kinds of fabrication methods led to significant differences in the crystallographic form, spherulite size and crystalline content and perfection as well. Accordingly, it is attempted to explain the reasons for the opposite trends of changes in the mechanical properties for these two blends. © 2007 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 45: 1176–1186, 2007