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51.
ISO质量体系认证标准要求对计量数据进行计算和评价。公司的信息管理系统可以自动计算统计参数,并可以方便的进行分析和查询,提高企业工作效率,改善产品质量。论文为国家自然科学基金“现代制造质量控制、溯源中若干理论问题与技术基础的研究”(项目号:59735120)中的一部分。  相似文献   
52.
In order to obtain information on the lattice location of B atoms in graphite, channelling experiments have been performed at room temperature with a proton beam of an energy of 0.65-0.77 MeV for the 〈0 0 0 1〉 axial channel in highly oriented pyrolytic graphite (HOPG) crystals doped with 0.32 at.% B. The B atoms are detected by measuring α-particles which are emitted as a result of a nuclear reaction 11B(p,α)αα. It is clearly demonstrated that most of B atoms are shadowed behind the 〈0 0 0 1〉 C atomic rows. Taking account of the already reported experimental results on a change of lattice parameters by B-doping, it is concluded that most of B atoms are located at substitutional sites. It is also observed that B-doping introduces lattice strain on the c-plane. In addition, the presence of a small portion of interstitial B atoms is suggested.  相似文献   
53.
Reply to Finley's (1987; see record 1988-00015-001) critique of rational-emotive philosophy, which claims that Ellis's (1981) response to Sharkey's (1981) criticisms of rational-emotive psychology reveals logical and philosophical confusion. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
54.
P油田长4+52小层孔隙度三维模型的建立   总被引:1,自引:0,他引:1  
为了更准确的评价P油田主要产层长4 52小层的储集能力,以随机模拟建模方法对该层的孔隙度进行研究,建立孔隙度分布三维模型。研究表明,长4 52小层属于低孔储层,平均孔隙度为11.85%。根据P油田储层物性分类原则,该储层在本区分布较为广泛,是今后挖潜的重点。  相似文献   
55.
BACKGROUND: This study aimed to investigate the synthesis of zeolites from paper sludge ash (PSA) with added diatomite to remove both NH4+ and PO43? for water purification. The PSA had low Si and significant Ca contents. Four types of diatomite: white (T‐W) and brown (T‐B) from deposits of marine origin in Takanosu, and white (S‐W) and gray (S‐G) from lacustrine deposits in Shonai, were added to NaOH solution to increase the Si content and thereby synthesize zeolites with high cation exchange capacity (CEC). RESULTS: The order of the amounts of Si extracted from the diatomite to the alkali solution was S‐W > T‐W = T‐B > S‐G, which correlates with the amorphous SiO2 content of diatomite. The original ash without addition of diatomite yielded hydroxysodalite with CEC of about 1.0 mmol g?1. For all samples, the addition of diatomite to the solution yielded zeolite‐P with a higher CEC, but the addition of excess Si inhibited the synthesis of zeolite‐P, and the CEC of the product was low. A product with high CEC including zeolite‐P was obtained in a solution with around 500 mmol L?1 of Si concentration, and had the ability to remove both NH4+ and PO43?. CONCLUSION: Diatomite has the potential for used as an additive for the synthesis of high CEC zeolite from PSA. The product with zeolite‐P exhibited relatively high CEC, capacity for NH4+ uptake, and the ability to remove PO43? by precipitation, which is preferable for water purification applications. Copyright © 2008 Society of Chemical Industry  相似文献   
56.
The forming behaviour at high temperature of a modified 9%Cr‐1%Mo (P91) ferritic steel containing B and Ti for elevated temperature service was investigated. The microstructure of the as‐received material is mainly martensite at room temperature, but special etching revealed prior austenite grains of about 25 μm in size. Torsion tests were conducted at temperatures in the range 850 to 1250 °C to simulate the hot rolling process under comparable conditions of temperature, strain rate and strain. The deformation data obtained from these tests were correlated with the Garofalo equation with a stress exponent of 4.6 and an activation energy of 315 kJ/mol. This equation was used to predict the formability behaviour for the rolling process and also to determine the maximum forming efficiency and stability of the steel. A temperature of 1200 °C is recommended to conduct the forming process.  相似文献   
57.
杨勇 《微计算机信息》2006,22(29):136-137
介绍了基于CAN总线的分布式果园气象监测系统,重点描述了单片机P87C591的特点及以它为控制核心构成的监测网络节点的实现。  相似文献   
58.
综述了粉末冶金温压工艺的研究进展,概述了温压工艺的粉末原料、聚合物、温度、压力、烧结环节对温压工艺的影响和温压工艺的致密化机理。详细介绍了温压工艺的新进展—流动温压、高压温压等,并对其应用前景进行了展望。  相似文献   
59.
粉末冶金低合金钢的制备和性能研究进展   总被引:1,自引:0,他引:1  
从粉末制备、成形工艺、烧结工艺和组织控制等方面,系统的介绍了国内外粉末冶金低合金钢的制备技术,并对其研究方向和应用前景进行了展望。  相似文献   
60.
An amorphous natural brannerite sample was chosen to study the annealing of the radiation damage through thermal recrystallisation, and subsequently to evaluate the effect of radiation damage on its aqueous durability. Microstructural characterisation of the natural brannerite revealed minor alteration along the rim of the crystal and within cracks. The formation of UO2 particles and soluble Pb–Ca-rich aluminosilicate glass is responsible for the higher U and Pb releases from the recrystallised brannerite. In general, natural brannerite has been shown to be resistant to dissolution over geological time, therefore minor brannerite inclusions in ceramic formulations for immobilisation of actinide-rich radioactive wastes should not have a detrimental effect on the long-term chemical durability of the wasteforms.  相似文献   
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