水体污染检测用锡质量控制标准物质研究

研制国家级水质锡质量控制用标准物质,作为锡分析检测的质量控制标准。依据国家标准样品工作导则要求,制备锡标准物质;采用原子荧光光谱法对样品进行均匀性和稳定性研究;以多个实验室协作分析定值的统计结果确定标准值,并进行不确定度评估。经检测锡标准物质均匀性良好,稳定性可达24个月以上;样品量值准确,与美国同种标准物质进行比对具有可比性。研制的锡标准物质符合国家标准物质的技术要求,可用于水质锡元素检测的质量控制、分析方法研究以及分析实验室能力验证等方面。     

水质监测锂环境标准样品研究

针对我国缺少国家级锂环境标准样品的情况,研究介绍锂环境标准样品的研制方法。锂环境标准样品采用重量法制备,用原子吸收法对样品进行均匀性和稳定性研究;多家实验室分别采用AAS、ICP-AES、AFS、ICP-MS协作分析定值后数理统计确定标准值,并进行不确定度评估。结果表明:锂环境标准样品的均匀性良好,稳定性符合要求;与美国同种标准物质具有可比性,可用于仪器校准、分析方法的评价与验证、实验分析的质量控制和能力验证等方面。     

水污染监测用水中硝基苯标准样品的研制

对水污染监测用水中硝基苯标准样品进行制备和研究。介绍样品的制备方法,包括配制试剂的验证、均匀性和稳定性检验、分析定值和测定数据的统计检验等方面。采用质量法制备,用国家标准分析方法《硝基苯还原偶氮分光光度法》对样品进行均匀性和稳定性研究,并进行不确定度评估。结果表明,硝基苯标准样品的均匀性良好,至少可稳定36个月;标准值为1.01 mg/L,相对扩展不确定度为4.0%(k=2),国家标准编号为GSB 07-3182—2014。     

白藜芦醇标准样品的研制

依据GB/T 15000——2008标准样品工作导则,研制白藜芦醇标准样品。采用高速逆流色谱方法制备白藜芦醇样品,通过UV、IR、MS和NMR等方法对白藜芦醇样品进行结构鉴定,并进行均匀性、稳定性检验。采用8家实验室对制备的白藜芦醇样品进行联合定值,并对定值结果进行数据分析。白藜芦醇标准样品均匀性和稳定性良好,其定值结果为99.79%,置信度95%的扩展不确定度为0.66%。所制备的白藜芦醇样品满足标准样品工作导则的要求,可用于有关白藜芦醇检测方法的校正和相关产品的质量控制。     

熔体质量流动速率的测定能力验证研究

利用自制的聚乙烯样品来评价各参加实验室的熔体质量流动速率的检测能力.采用单因子方差分析法对制备的聚乙烯样品进行均匀性、稳定性检验;以各参加实验室结果的中位值作为测试熔体质量流动速率的指定值,以标准化四分位距(NIQR)作为变动性度量值(目标标准偏差),采用Z比分数评价各参加实验室的测试结果.研究表明,所制备的能力验证聚乙烯样品符合均匀性、稳定性要求,本项目所采用的方法可评估各实验室对熔体质量流动速率的检测能力.     

二醋酯贴衬织物国家标准样品的研制

本文采用纱线染缸煮炼方式制备二醋酯贴衬织物标准样品,研究了其色牢度级结果表征方法,提高了结果评定精度,评估了标准样品均匀性和稳定性。采用多家实验室进行协同定值,并对定值结果的不确定度进行了评定。二醋酯贴衬织物标准样品的沾色色牢度标准值为4.6级,扩展不确定度(k=2)为0.2级。     

红外测油仪用标准物质的研制

为保证分析测量结果的准确可靠,研制了浓度为1000μg/mL的红外测油仪用溶液标准物质。以称量-容量法制备,计算结果定值,对原料进行了纯度分析、制备方法控制,考察了样品均匀性和稳定性,评定了所配制标准物质浓度定值的不确定度。通过与GBW(E)130171比对,验证了标准物质的定值结果准确可靠,相对扩展不确定度<2%(k=2),有效期限为12个月。该标准物质已被批准为国家二级标准物质。     

校准用溶液标准物质的量值不确定度评定

ISO导则35《标准物质定值及通用统计学原则》中要求,采取称量法制备、定值的标准物质,需评估由称量法制备、均匀性、稳定性及核验四个分量引入的不确定度.对于称量法制备的校准用溶液标准物质,制备过程中由天平和容量器具引入的不确定度往往较小且易于评估,而制备过程中其它来源不确定度以及核验、均匀性、稳定性不确定度的评估方法会对该类标准物质的总体量值不确定度水平产生显著影响.本文以导则35及GUM原则为基础,提出了针对该类标准物质量值不确定度评定的新型改进方法,以达到既确保评估的全面性,又通过适当的方案设计,去除各不确定度分量中的交叉重叠成分,避免不确定度评定结果盲目扩大的目的.     

腹泻性贝类毒素基体标准物质的研制

为了保证小鼠生物法、荧光衍生法、质谱法等对腹泻性贝类毒素检测结果的准确、可靠和可比,以紫贻贝为基体,采用添加法研制了一种含腹泻性贝类毒素软海绵酸(OA)的冻干粉形式的贝类毒素基体标准物质.采用LC-MS/MS法,以多家定值的方式对标准物质中的OA进行定值.均匀性检验结果表明该样品均匀,短期稳定性和6个月的稳定性考察表明样品稳定性良好.经过对影响定值结果的称样量、定容、校准物、校准曲线等因素的考察,进行不确定度评定,标准物质中OA的含量及不确定度为2.96土0.50μgOA/g(k=2).该标准物质可以用于腹泻性贝类毒素检测过程的方法验证与质量控制等.     

猪尿冻干粉中盐酸克伦特罗标准物质的研制

研制一套4种浓度水平的猪尿冻干粉中盐酸克伦特罗标准物质,以健康安全的猪尿作为空白基体,利用添加的方法,经过均匀性和稳定性检验,由8家实验室采用液相色谱-串联质谱法对该套标准物质进行协同定值,并进行不确定度评估。结果表明该套标准物质均匀性良好,在4℃条件下保存稳定性在1年以上,标准物质中CLB的含量及不确定度分别为:0.65±0.15,1.28±0.44,3.78±0.46,11.5±1.8ng/mL(k=2)。该标准物质可应用于猪尿中盐酸克伦特罗检测过程的方法验证和检测结果质量控制等。     

Estimation of Parameters of Universal Distribution of Moments of Failure of Products

A method is proposed for estimating the parameters of a mixture of exponential and Weibull distributions for which the accuracy of preliminary estimates obtained by graphical analysis is refined in accordance with the criterion of maximum likelihood. The efficiency of the proposed method is supported by the results of statistical modeling.     

Evaluation of optical properties of highly scattering media by moments of distributions of times of flight of photons

A novel method for the determination of the optical properties of tissue from time-domain measurements is presented. The data analysis is based on the evaluation of the first moment and the second centralized moment, i.e., the mean time of flight and the variance of the measured distribution of times of flight (DTOF) of photons injected by short (picosecond) laser pulses. Analytical expressions are derived for calculation of absorption and of reduced scattering coefficients from these moments by application of diffusion theory for infinite and semi-infinite homogeneous media. The proposed method was tested on experimental data obtained with phantoms, and results for absorption and reduced scattering coefficients obtained by the proposed method are compared with those obtained by fitting of the same data with analytical solutions of the diffusion equation. Furthermore, the accuracy of the moment analysis was investigated for a range of integration limits of the DTOF. The moment analysis may serve as a comparatively fast method for evaluating optical properties with sufficient accuracy and can be used, e.g., for on-line monitoring of optical properties of biological tissue.     

Assessment of intakes of mixtures of radionuclides

Australia has several uranium mines and a large number of mineral sand mines, with associated processing facilities. Exposures resulting from these mining and processing operations usually involve intakes of mixtures of radionuclides. This work describes the development of a suite of first order, linear compartment models, based on the ICRP Publication 66 respiratory tract model, and an analytical solution to the decay equations, for assessing the consequences of such intakes. The computer programs based on these models directly compute excretion, organ retention and organ and whole-body doses for intakes of either single radionuclides or any mixture of radionuclides belonging to the same radioactive decay chain. The intake can be via inhalation, ingestion or injection, and can be acute, chronic or of limited duration. The starting concentration and degree of secular (dis)equilibrium can be specified for each radionuclide. No assumptions need to be made about the relative magnitudes of the radioactive half-lives of the different nuclides.     

Estimation of potentialities of methods of summation of direct measurement errors

Conventional methods for summation of direct measurement errors are considered. Conditions under which these methods provide consistent results are stated. It is proposed to utilize for characteristic of the total error, its interval estimator or the half-sum of the value obtained by adding up its arithmetic and geometric random errors.Translated from Izmeritel'naya Tekhnika, No. 4, pp. 10–12, April, 1995.     

空压机轴承箱蜗壳温度探头油封改造

由于空压机进气侧轴承箱蜗壳温度探头密封效果不好,使空压机及其后续管道受到油污染。后将温度探头的O形圈密封改为骨架油封,杜绝了轴承箱漏油问题。文章简介空压机的结构和技术参数,详细介绍了骨架油封的制作和优点。     

Determination of parameters of microstructural inhomogeneity of deformation of metals by the method of modeling

The article suggests a method of evaluating the microstructural inhomogeneity of deformation of metals by modeling. The method includes the measurement of deformations of metal according to meshes of a dividing grid with small base and the calculation of the distribution parameters of microdeformations in model representation. It is shown that the modeling method makes it possible objectively to evaluate the microinhomogeneity of deformation of metals independently of the chosen mesh size of the dividing grid. New structural characteristics are introduced: the base and wave of variation expressing the degree of crumbling or amalgamation of metal grains by inhomogeneity of deformation.Translated from Problemy Prochnosti, No. 7, pp. 40–44, July, 1991.     

Characteristics of mechanical properties of materials in studies of conditions of attainment of marginal states

It is shown that conditions of attainment of marginal states in the material of structural components are formulated on the basis of analysis of force and deformation criteria of formation and development of destruction. The parameters of these criteria are data on types of structural materials, standard and special characteristics of their mechanical properties, structural forms of considered elements of the equipment, and their operating stress loading. In this case, the construction of a system of state equations for describing interrelation of current damage, external actions, and responses to them is based on the concept of calculating variations in properties of materials at all stages of the design life cycle.     

Analysis of anisotropy of properties on the basis of studies of texture of coarse-grained ingots of thermoelectric materials

An analysis of anisotropy of the properties of a Bi₂Se_0.3Te_2.7 solid solution was carried out using construction of demonstrative surfaces for thermoelectric effectiveness and thermal expansion coefficients. It is shown that the texture is an important factor forming anisotropy of properties and technological fitness of ingots for manufacturing modules. Anisotropy of properties based on the studies of the ingot textures obtained using the float-zone method and Bridgman method (growing thermoelectric plates in a flat cavity) was studied.     

Analysis of the rate of propagation of the wave of change of boiling modes

An approximate analytical expression is derived for the velocity of the front of the wave of change of boiling modes on a rod and on a plate. The impact of the Thomson effect and of the heater orientation in the gravity field is included. Adequate agreement is demonstrated between the derived relations and experimental data.