对钢板拉伸性能指标的测量不确定度评定方法的新认识

抗拉强度、屈服强度是钢板产品最重要的质量指标,用户验收时通常会自行取样做拉伸试验,对相关的力学性能指标进行验证;从以往的情况看,往往有一些用户和个别第三方实验室出现验收结果与出厂检验结果不一致的问题.为了判断检测结果的可靠性,并查明出厂检测与用户验收检测的结果不一致的原因,需要对相关性能指标和测量不确定度进行比对分析,而此时能被双方接受的一种可科学方便地对相关检测项目的测量不确定度进行可靠评定的方法是进行比对分析的前提.当前,如何科学合理地进行测量不确定度的评定和应用是各类实验室普遍关心的问题,也是近年来检测质量研究的一个热点,相关的文献报道很多.作者目前所看到的众多文献中,对于拉伸试验结果的测量不确定度评定几乎都是用直接校验的结果结合部分重复测量的数据计算拉伸试验相关检测项目的测量不确定度.而有很多实例证明用直接校验的结果往往不能可靠和全面地对测量不确定度进行评定,这主要有两方面的困难1、有些影响试验结果的因素难以定量;2、另一些影响试验结果的因素在评定不确定度时会被遗漏.为了可靠地对拉伸试验相关检测项目的测量不确定度进行评定,本文借鉴国际硬度试验标准草案中测量不确定度评定的方法,建立起一套以标准物质实测结果为基础的计算屈服强度Rp0.2、抗拉强度Rm和最大力下的总伸长率Agt的测量不确定度的方法.     

热电偶自动检定系统测量结果的不确定评定

热电偶是钢铁企业生产过程中用于测量温度的重要传感器,它的准确与否直接关系着产量和产品质量。热电偶自动检定系统对检定(校准)结果具有重要影响,因此,必须对其测量结果的不确定度进行评定。主要介绍了热电偶校准原理,对系统校准结果的不确定度进行了评定和小结,给出了影响测量结果不确定度的主要来源,以方便使用者准确、规范使用该检定系统。     

茶叶中稀土氧化物总量的测量不确定度评估

[目的]研究建立多元素总量检测时的测量不确定度的评估程序.[方法]采用电感耦合等离子质谱法同时检测茶叶中16种稀土元素,以计量检定规程<测量不确定度评定与表示>为依据,建立数学模型,分析其不确定度的主要采源.通过对测量过程中不确定度分量进行分析和合成, 计算出茶叶中稀土氧化物A类、B类不确定度及包含因子,进一步算出稀土氧化物总量的扩展不确定度.[结果]通过计算测量过程中的A类、B类不确定度和自由度,从JJF1059-1999技术规范的附录A中查出包含因子K,计算出扩展不确定度U.说明了多元素总量检测时测量不确定度的评估程序.[结论]该方法可以用来评估多元素总量检测的不确定度.     

高氯酸氧化滴定法测定锰含量不确定度评定

采用高氯酸氧化滴定法测定高碳锰铁中锰含量,应用测量不确定度的评定方法,统计分析了测量过程中的不确定度来源,运用数学模型,对高氯酸氧化滴定法检测高碳锰铁中锰含量的结果进行不确定度评定.计算出相对合成不确定度和扩展不确定度.得出分析结果的置信区间为73.58％-74.08％.     

熔融法测定铁矿石中SiO2的测量不确定度评定

介绍了X射线荧光光谱熔融法检测铁矿石中SiO2的方法,对X射线光谱仪熔融法测定铁矿石中SiO2的分析结果产生不确定度的原因进行了分析.根据CSM01010108-2006对其进行了评定,建立了相关数学模型.并将评定的参数引用于日后的测量结果的不确定度评定,为其他元素的测量不确定度评定提供了可借鉴的经验.     

冷轧生产线酸液中游离盐酸测定的不确定度评定

一切测量结果都不可避免地具有不确定度,测量不确定度是评价测量结果可靠性、可比性的重要指标。本文对冷轧生产线上酸液中游离盐酸含量的测量不确定度进行了评定,分析了测量不确定的来源,并找出影响测量不确定度的因素。     

基于控制图评定实验室ICP法测定铁矿石中硅含量的不确定度

本文使用一段较长时期的36个铁矿石标准样品检测数据,在验证数据的正态性和独立性后,依据数据的统计计算结果建立控制图并对检测质量控制情况进行解释评价。通过分析控制图数据确认实验室检测铁矿石硅含量的测量系统处于统计受控状态,其偏倚的不确定度和其他效应可忽略,根据CNAS-GL022相关规则,评定实验室采用GB/T 6730.63-2006规定的ICP法测定铁矿石硅含量结果的扩展不确定度:U=0.034%(k=2)。本文适用于对方法熟练掌握,相关质控数据质量和数量符合要求的实验室实用而便捷地评定测量不确定度。     

测量不确定度对En值法评价气体检测能力验证结果的影响探究

在环境空气检测能力验证工作中,由于气体容器、充装方法等影响,气体样品的制备通常会采用逐瓶制备的方式,每瓶气体样品的指定值会存在一定的差异,因此气体检测能力验证结果往往采用E_n值法进行评价。采用E_n值法时,实验室测量不确定度直接影响能力验证评价结果,实验室正确评定其测量不确定度是E_n值法得以正确合理使用的必要条件。以空气中二氧化硫检测能力验证计划为例,通过分析E_n值与不确定度的关系,确定实验室测量不确定度的有效范围,并据此给出两组实验室的能力评定标准差分别为0.64 μmol/mol和1.23 μmol/mol;有效的不确定度范围分别为0.34~1.92 μmol/mol和0.66~3.69 μmol/mol,为有效采用E_n值法评价实验室结果和指导实验室正确评定测量不确定度提供参考。     

X-射线荧光光谱法测定石灰石中CaO含量不确定度的评定

采用X射线荧光光谱法测定石灰石中CaO含量,分析了分析结果不确定度产生的原因,并建立相应数学模型.对测量重复性、标准物质、校准曲线回归、检测条件、试样称量和熔剂中杂质引起的不确定度分量进行评定,计算了合成标准不确定度和扩展不确定度,并给出石灰石中氧化钙含量测定结果的报告.评定结果表明,校准曲线回归引起的不确定度对总不确...     

红外吸收法测定钛合金中氢含量的不确定度评价

对红外吸收法测定钛合金中氢含量进行了评价,根据测量不确定度评定理论对检测过程产生的不确定度进行分析,得到钛合金中氢的测量结果为(0.008 903±0.0033)%,k=2,该不确定度的评价方法适合钛合金中氢含量的测定,最后提出了减小不确定度的方法.     

转炉炉壳热应力分析

根据实际转炉建立实体模型。以有限元为手段,考虑了炉衬和炉壳材料的物性参数随温度变化的特点和炉衬与炉壳之间膨胀间隙,计算了转炉炉壳在温度载荷和炉衬膨胀压力同时作用下的热应力。所得结果可为转炉炉壳设计提供依据。     

焦炭热性能指标意义浅析

通过对焦炭在高炉内的历程及其变化规律的剖析,阐述焦炭热性能指标的意义,形象地把焦炭在高炉内的损耗分为三部分(M1,M2,M3)。指出M2对焦比及焦炭价格有一定的指导作用。     

Results of treatment of cancer of the cardia

Cancer of the cardia is traditionally discussed with cardiac cancer of the lower portion of the esophagus and upper gastric cancer invading the esophagus, and the specific characteristics of cancer of the cardia have never been clearly defined. We reviewed the outcome of 172 patients with adenocarcinoma of the cardia who had undergone radical surgery between 1949 and 1994 in the Division of Gastrointestinal Surgery of the Cancer Institute Hospital. The centers of the tumors were located within 2 cm above and below the boundary between the esophagus and the stomach, and their longitudinal diameter was less than 8 cm. We divided the patients into an early period (1949-1979; n = 79) and a late period (1980-1994; n = 93), and focused on the historical transition. There were no differences in patient gender or histology between the two periods. However, the late period was associated with fewer cases of esophageal invasion and shorter longitudinal diameter, as the age of the population advanced. The number of advanced cancers such as the localized and infiltrative type had decreased, and early cancer and early clinical stage had become more common, but despite the fact that the number of early cancers had increased, extended dissection, such as thoracic and paraaortic lymph node dissection, was performed more frequently. By clinical stage, the long-term outcome markedly improved in Stage I patient in the late period, and tended to improve in Stage II and III patients. This appears to have been attributable to the prevention of micrometastasis by extended dissection, although the number of early cancers is another major potential cause. There were no differences in the outcome of Stage IV patients between the two periods, and further advances in multimodality therapy must be awaited. The range of resection is basically proximal gastrectomy, and if there are adequate indications, the prognosis is favorable. In view of the status of lymphatic flow and lymph node metastasis, and long-term results, lateroaortic lymph node dissection is important. Since the number of early cancer patients has been increasing, if intraabdominal recurrence is prevented, intrathoracic lymph node dissection will contribute greatly to the outcome of such patients.     

Effect of antibiotics of chemotaxis of human leukocytes

The effect of 20 different antibiotics on chemotaxis by human neutrophils was studied. Human leukocytes incubated with chloramphenicol, rifampin, sodium fusidate, and tetracyclines in vitro showed markedly depressed migration. The mechanisms by which these antibiotics affect leukotaxis are discussed.     

Quality of life of relatives of mental patients

Usage of quality of life of psychiatric patients' relatives as the parameter of estimation of the quality of psychiatric care is considered. By means of standard questionnaire elaborated by the authors as well as by means of both individual and group conversations the quality of life was analyzed in 40 relatives which lived together with psychiatric patients. Different spheres of their life and difficulties (financial, social-psychologic, production) were examined in families with such patients. The defects of psychiatric care that had direct influence on the quality of life of the psychiatric patients' relatives are outlined.     

The effect of amount of possession of the trait of hostility on accuracy of perception of hostility in others.

Some theories of personality hold that an individual's perception of others is influenced by his own personality characteristics; more specifically, that a trait of low social value will be projected more into others, and that insight into the possession of these characteristics reduces this distortion. These 2 hypotheses were tested by having a group of college students rate each other (including themselves) on degree of friendliness or hostility. Agreement with group rating about self yielded the insight score. In general, the hypotheses were supported; the "friendly" Ss were most accurate in their perception of others, and insight was positively associated with accurate perception. From Psyc Abstracts 36:04:4HL16M. (PsycINFO Database Record (c) 2010 APA, all rights reserved)