核装置机械部件设计和建造规则中 1、2和3级设备设计要求差异分析

核装置机械部件设计和建造规则(RCC-MR 2007)是ITER装置中构成等离子体腔室第一道密封屏障的设备或部件设计和制造的依据。本文在研究RCC-MR 2007主要内容的基础上,分析了RCC-MR 2007中1、2、3级机械设备设计相关的通用要求、材料要求、设计通则、设备性能分析要求之间的区别,同时对1、2、3级壳体、管道、箱式结构、热交换器、阀门和波纹管设计要求之间的差异进行了分析。     

庆大霉素功能组分的定量分析方法研究

针对目前庆大霉素功能组分含量检测方法的成本昂贵和使用仪器的限制,建立了一种快速经济准确的薄层色谱结合比色法,以甲醇-氯仿-25%氨水(1∶1∶1)为展开剂,碘蒸汽一次显色,收集斑点以乙酰丙酮及甲醛为显色剂,进行二次显色,并建立420 nm处的浓度-吸光度曲线.结果表明,庆大霉素在2-100 mg范围内线性关系良好r=0.9986,三组分含量测定误差分别为0.188%、0.265%、3.701%.本法仅使用最简便宜得的仪器与药品就能够对庆大霉素各功能组分进行定量分析测定,适合于工业分离中检测应用.     

关于两类复微分方程组的允许解

本文利用Nevanlinna值分布理论讨论了复平面内两类复微分方程组的允许解的存在性问题,改进了文[1]中的一些定理,从而得到了更精确、更一般的结果     

加权模糊C-均值聚类

将经典的模糊C-均值聚类中的欧氏距离推广到广义欧氏距离,得到了加权模糊C-均值聚类的迭代公式,实证分析表明加权模糊C-均值聚类的结果与主成分分析的排序基本一致,特别适用于大样本的聚类与排序。     

X射线荧光光谱法测定石灰岩和白云岩中主次量组分

建立用X射线荧光光谱法同时测定石灰岩和白云岩中主次量组分(CaO、MgO、Al2 O3、SiO2、Fe2O3、TiO2、K2O、Na2O、MnO、P2O5)的快速分析方法,在优化条件下,采用国家标准样品建立的标准工作曲线和基体校准一体回归方程进行谱线重叠干扰和基体效应校正.实验结果表明,各元素的检出限在80～280μg...     

Diffusion approximation for the components in critical inhomogeneous random graphs of rank 1.

Consider the random graph on n vertices 1,…,n. Each vertex i is assigned a type x_i with x₁,…,x_n being independent identically distributed as a nonnegative random variable X. We assume that EX³< ∞. Given types of all vertices, an edge exists between vertices i and j independent of anything else and with probability \begin{align*}\min \{1, \frac{x_ix_j}{n}\left(1+\frac{a}{n^{1/3}} \right) \}\end{align*}. We study the critical phase, which is known to take place when EX² = 1. We prove that normalized by n^‐2/3the asymptotic joint distributions of component sizes of the graph equals the joint distribution of the excursions of a reflecting Brownian motion with diffusion coefficient \begin{align*}\sqrt{{\textbf{ E}}X{\textbf{ E}}X^3}\end{align*}and drift \begin{align*}a-\frac{{\textbf{ E}}X^3}{{\textbf{ E}}X}s\end{align*}. In particular, we conclude that the size of the largest connected component is of order n^2/3. © 2013 Wiley Periodicals, Inc. Random Struct. Alg., 43, 486–539, 2013     

西瓜内生菌的挥发性成分分析及其发酵香料在卷烟中的应用

对新鲜西瓜内生菌进行分离纯化,共获得3株纯系微生物。通过筛选获得一株代谢产物香气优雅、甜润、生长迅速的菌株。利用GC-M S对其发酵产物进行分析,结果表明经该微生物代谢,种子液成分由苯、胺、酚等物质转化成了酸和醇等主要香气成分物质,苯含量从58.65%降到了1.35%,其次酸类物质和醇类物质分别占峰面积的55.06%和42.64%。利用该菌株发酵制备得到的发酵型烟用香料产品FM XG-A具有使烟香柔和、细腻、饱满的作用。     

Optimal component selection based on cohesion & coupling for component based software system under build-or-buy scheme

Component based software system approach is concerned with the system development by integrating components. The component based software construction primarily focuses on the view that software systems can be built up in modular fashion. The modular design is a logical collection of several independent developed components that are assembled with well defined software architecture. These components can be developed in-house or can be obtained commercially from outside market making build versus buy decision an important consideration in development process. Cohesion and coupling (C&C) plays a major role in determining the system quality in terms of reliability, maintainability and availability. Cohesion is defined as the internal interaction of components within the module. On the other hand, coupling is the external interaction of the module with other modules i.e. interaction of components amongst the modules of the software system. High cohesion and low coupling is one of the important criteria for good software design. Intra-modular coupling density (ICD) is a measure that describes the relationship between cohesion and coupling of modules in a modular software system and its value lies between zero and one. This paper deals with the selection of right mix of components for a modular software system using build-or-buy strategy. In this paper, fuzzy bi-criteria optimization model is formulated for component selection under build-or-buy scheme. The model simultaneously maximizes intra-modular coupling density (ICD) and functionality within the limitation of budget, reliability and delivery time. The model is further extended by incorporating the issue of compatibility amongst the components of the modules. A case study is devised to explain the formulated model.     

巴豆种子油的GC-MS分析

巴豆种子经石油醚或无水乙醇提取得巴豆种子油，通过气相色谱－质谱联用仪（GC－MS）测定其中的化学夸分，结果显示，巴豆种子油中含有26个组分，本文确定了其中22个组分的结构。     

The structure of even factors in claw-free graphs

Recently, Jackson and Yoshimoto proved that every bridgeless simple graph G with δ(G)≥3 has an even factor in which every component has order at least four, which strengthens a classical result of Petersen. In this paper, we give a strengthening of the above result and show that the above graphs have an even factor in which every component has order at least four that does not contain any given edge. We also extend the above result to the graphs with minimum degree at least three such that all bridges lie in a common path and to the bridgeless graphs that have at most two vertices of degree two respectively. Finally we use this extended result to show that every simple claw-free graph G of order n with δ(G)≥3 has an even factor with at most components. The upper bound is best possible.