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51.
52.
傅里叶变换红外光谱法快速测定5个品种大豆的主要组分   总被引:4,自引:0,他引:4  
探索作物育种过程中从大量样本中快速筛选有益突变体的新方法.利用傅里叶红外光谱法从整体上对5种大豆的主要组分进行测定和分析.结果表明:大豆的脂肪酸、皂苷、异黄酮(3298-1746cm-1)、蛋白质(1655-1398cm-1、1059cm-1)和核酸、磷脂(1240-1159cm-1、1001cm-1)等主要组分均具有...  相似文献   
53.
Component based software development (CBSD) is well acknowledged as a methodology which establishes reusability of software and reduce development cost effectively. While developing enterprise application using component based software engineering (CBSE) methods, software component selection plays a very important role in the process of component retrieval, adaptation and assembly. However, most of current researches focus on technical aspects from domain engineering and application engineering to improve reusability and system efficiency rather than application of optimization methods in CBSD management, especially application in component selection. Moreover, few existing researches have concerned about the situation where a software developer or enterprise develops multi-applications at the same time. By introducing the concept of reusability and a new formulation of compatibility matrix, an optimization model is proposed to solve component selection problem considering reusability and compatibility simultaneously. The model can be used to assist software developers in selecting software components when multi-applications are undertaken concurrently. Four experiments are conducted with the purpose to provide some insights in management perspective.  相似文献   
54.
Let (X,d)(X,d) be a metric space endowed with a graph GG such that the set V(G)V(G) of vertices of GG coincides with XX. We define the notion of GG-Reich type maps and obtain a fixed point theorem for such mappings. This extends and subsumes many recent results which were obtained for other contractive type mappings on ordered metric spaces and for cyclic operators.  相似文献   
55.
Given a graphG = (V, E), leta S, S L, be the edge set incidence vectors of its nontrivial connected subgraphs.The extreme points of = {x R E: asx |V(S)| - |S|, S L} are shown to be integer 0/± 1 and characterized. They are the alternating vectorsb k, k K, ofG. WhenG is a tree, the extreme points ofB 0,b kx 1,k K} are shown to be the connected vectors ofG together with the origin. For the four LP's associated with andA, good algorithms are given and total dual integrality of andA proven.On leave from Swiss Federal Institute of Technology, Zurich.  相似文献   
56.
ICP-AES方法同时测定铜精矿中十三种成份   总被引:2,自引:0,他引:2  
本文选用聚四氟乙烯高压消化罐、HF+逆王水+HClO4混合酸消化处理铜精矿样品,在ARL3520B单道顺序扫描型光谱仪上测定了13种成分的含量。较系统地研究了样品消化温度、时间、ICP测定的最佳光谱条件,采用人工基体匹配和校正因子相结合的办法校正基体成份的光谱干扰,人工合成含有定量基体元素的多元素混合标准溶液并用于仪器的校准获得满意的校准曲线,将建立的方法应用于样品的测定,准确度、精密度均令人满意。  相似文献   
57.
This paper reports on a study that introduces and applies the K5Connected Cognition Diagram as a lens to explore video data showing teachers’ interactions related to the partitioning of regions by axes in a three-dimensional geometric space. The study considers “semiotic bundles” ( Arzarello, 2006), introduces “semiotic connections,” and discusses the fundamental role each plays in developing individual understanding and communication with peers. While all teachers solved the problem posed, many failed to make or verbalize connections between the types of semiotic resources introduced during their discussions.  相似文献   
58.
We are interested in (right) modules M satisfying the following weak divisibility condition: If R is the underlying ring, then for every r ∈ R either Mr = 0 or Mr = M. Over a commutative ring, this is equivalent to say that M is connected with regular generics. Over arbitrary rings, modules which are “minimal” in several model theoretic senses satisfy this condition. In this article, we investigate modules with this weak divisibility property over Dedekind-like rings and over other related classes of rings.  相似文献   
59.
分析浙产竹叶椒不同部位的挥发性化学成分.用水蒸气蒸馏法提取挥发性成分,采用气相色谱-质谱联用法(GC-MS)测试,并用面积归一化法计算出各组分的相对百分含量.通过计算机自动检索,从浙产竹叶椒叶、茎皮和果实中分离鉴定出的组分数分别为60、16和12.浙产竹叶椒叶、茎皮和果实3个部位的挥发性成分及含量存在很大的区别,可为进...  相似文献   
60.
本文探讨了以CID作检测器的全谱直读ICP光谱仪测定钢中稳定夹杂物化学组分的方法,并从试液制备、谱线选定、介质影响、方法检出限和精密度等方面进行了讨论,样品测定结果较好,满足了工作的需要。  相似文献   
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