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91.
92.
镍、铜低合金奥贝球铁特性研究   总被引:2,自引:1,他引:1  
Tybul.  J Kowal.  A 《铸造》2001,50(9):537-540
阐明了含Ni、Cu质量分数分别为1.5%和0.8%的奥贝球铁的凝固/相变和性能特点。测定了凝固过程的微分热分析曲线、膨胀仪曲线、绘制了奥氏体连续冷却较变曲线和等温转变动力学曲线,对比分析了该成分铸铁的淬透性。测定了Ni、Cu合金化奥贝球铁的常温力学性能。  相似文献   
93.
International Maritime Organization regulations forces ship owners to measure NOx emission from ship engines, but standard equipped engine rooms has not installed any usable apparatus to analyze of exhaust gases. In this paper, we propose a method of NOx emission estimation based on the measurements of working parameters of two-stroke ship engine. This estimation consists of both the model enabling to determine a temperature and model of composition of a gas mixture in the combustion chamber of the engine. Application of such model does not require carrying out direct measurements of engine exhaust gases by exhaust gas analyzers. For the developed method, results of engine working parameters should be sufficient to estimate the NOx emission according to IMO regulations.  相似文献   
94.
95.
Errors in measurements of surface resistanceR s of HTS materials are due to discrepancy between a mathematical model describing physical phenomena and a real measurement environment, finite accuracy of measurements of theQ-factor, and finite accuracy of constants used for calculation ofR s . In this paper we analyze errors inR s due to uncertainties in theQ-factor, geometrical coefficients, loss tangent,R scu, and other factors when a cylindrical copper cavity with an HTS end plate, a stripline resonator, and sapphire rod resonators are used for HTS characterization.  相似文献   
96.
In this paper a discrete approach to analog modeling is presented. It is a functional-level, piecewise-linear (PWL) technique implemented in the VHDL environment. Since the models are based on some explicit formulas, fully behavioral architectural bodies have been proposed for them. Their most distinguishing features are discussed in detail. The models of practical circuits are illustrated with simulation results.  相似文献   
97.
Second-order active RC filters employing N identical operational amplifiers (OAs) are considered. the way to achieve the highest-order zero sensitivities of the dominant poles is shown. It leads to composite operational amplifiers (COAs) with a gain function of a polynomial form. the analysis of sensitivities, errors and location shifts of dominant poles as well as the effects of parasitic poles is also provided. the results have been confirmed by numerical analysis and an experimental verification.  相似文献   
98.
Personality structure was assessed in 4 countries (Canada, Finland, Poland, and Germany) using both an established verbal personality inventory and a new nonverbal personality questionnaire. A 5-factor structure was found to be highly robust in that it was replicated across the 4 cultures and across the 2 personality assessment methods. The data are discussed in terms of (1) the failure to support a semantic similarity interpretation of personality item responses, (2) the factorial validity of the new nonverbal personality questionnaire, and (3) the viability of the popular 5-factor model of personality. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
99.
实施项目群和项目组合管理——从标准到执行   总被引:2,自引:0,他引:2  
如今,人们再也不会将项目视为特殊的活动而将其置于组织真空中来执行。经过多年研究、传播及行业应用,项目群和项目组合管理的相关概念最终被诸多标准化机构采用,并形成了自己的知识体系。  相似文献   
100.
A mouse model has often been used in studies of p53 gene expression. Detailed interpretation of functional studies is, however, hampered by insufficient knowledge of the impact of mouse p53 mRNA’s structure and its interactions with proteins in the translation process. In particular, the 5′-terminal region of mouse p53 mRNA is an important region which takes part in the regulation of the synthesis of p53 protein and its N-truncated isoform Δ41p53. In this work, the spatial folding of the 5′-terminal region of mouse p53 mRNA and its selected sub-fragments was proposed based on the results of the SAXS method and the RNAComposer program. Subsequently, RNA-assisted affinity chromatography was used to identify proteins present in mouse fibroblast cell lysates that are able to bind the RNA oligomer, which corresponds to the 5′-terminal region of mouse p53 mRNA. Possible sites to which the selected, identified proteins can bind were proposed. Interestingly, most of these binding sites coincide with the sites determined as accessible to hybridization of complementary oligonucleotides. Finally, the high binding affinity of hnRNP K and PCBP2 to the 5′-terminal region of mouse p53 mRNA was confirmed and their possible binding sites were proposed.  相似文献   
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