PC-Ⅰ型数字式pH检定测量仪原理及校准

介绍了PC -Ⅰ型数字式pH检定测量仪的工作原理及校准方法、校准步骤     

PC—Ⅰ型数字式pH检定测量仪原理及校准

介绍了ＰＣ－Ⅰ型数字式ＰＨ检定测量仪的工作原理及校准方法、校准步骤。     

气相色谱仪检定装置的使用方法

依据JJG 700–1999《气相色谱仪检定规程》介绍气相色谱仪检定装置的使用方法。检定项目包括载气流速稳定性、柱箱温度稳定性和程序升温重复性、衰减器换挡误差以及检测器的灵敏度。给出了热导检测器(TCD)、火焰离子化检测器(FID)、火焰光度检测器(FPD)、电子俘获检测器(ECD)和氮磷检测器(NPD)检定时的色谱条件及使用注意事项。正确使用气相色谱仪检定装置能保证仪器测量数据的准确可靠。     

薄层色谱扫描仪检定方法探讨

为了解决薄层色谱扫描仪没有统一的量值溯源方法和标准装置的问题,建立薄层色谱扫描仪检定方法。通过对薄层色谱扫描仪各部分的结构进行分析,建立了薄层色谱扫描仪检定项目及计量性能要求。采用低压汞灯为标准器进行波长示值误差和重复性检定,采用薄层色谱标准板进行仪器重复性和线性检定。该检定方法能准确评价薄层色谱扫描仪的性能,为薄层色谱扫描仪的量值溯源提供技术支持。     

冶金分析仪器检定/校准中若干问题的探讨

对冶金分析仪器检定/校准中若干问题进行了探讨,包括计量标准、示值误差异常值的判断、不确定度、检定/校准项目、元素和测量范围等。计量人员用标准物质检定/校准仪器可以保证仪器测量结果的溯源,而实验室"自检定/自校准"不具备溯源性;示值误差的测量次数和测量数据的一致性需要利用统计规则进行判断,而不能直接取平均值作为测量结果;进行检定/校准结果的不确定度评定时,重复性引入的不确定度分量可以预先评估,评定检出限不确定度意义不大,实验室在进行一次测量时,一定程度上可以直接引用校准证书上的不确定度。校准的项目、元素和范围超出检定规程或者校准规范的要求时,计量机构需要进行方法确认及不确定度的评定。     

液相色谱仪示差折光率检测器的检定

以配置日本岛津制作所生产的RID–10A示差折光率检测器的液相色谱系统的检定为例,介绍了按照新版液相色谱仪检定规程JJG 705–2014的要求对液相色谱仪示差折光率检测器进行检定的过程。说明了检定方法更改的原因、新方法的优点及所解决的问题,总结了检定过程中的注意事项。     

发射光谱仪检定规程的探讨和应用

《发射光谱仪检定规程》是计量部门检定/校准电感耦合等离子体发射光谱仪、直读光谱仪及摄谱仪的重要依据,对规程进行了探讨,包括检定前的准备、测量数据的判断、标准物质的选择及计量性能的要求,提出了直读光谱仪应用于其它非冶金材料时的计量性能指标,如铜及铜合金、铝及铝合金、锌及锌合金等的成分分析。发射光谱仪检定规程也可以应用于油液分析用原子发射光谱仪、辉光放电发射光谱仪、金属原位分析仪、手持式合金分析仪、激光诱导击穿光谱仪等仪器的检定/校准,可作为计量人员的参考依据。     

恒电流激励的离子色谱电导检测系统

与常用的双电极,双脉冲激励方式不同,本文设计一种四电极,直流恒电流激励方式的新型离子色谱电导检测系统,有效地简化了电路结构,精确并且智能化地完成离子色谱信号的采集、放大、处理、谱图显示等功能.介绍了该检测系统的基本原理及硬件设计.实验结果表明系统运行良好,测量结果准确.     

酒类分析专用柱气相色谱仪校准用标准物质的选择

对酒类分析专用柱气相色谱仪校准用标准物质进行了研究.分别用乙醇中甲醇、乙醇中叔戊醇和甲苯中苯标准溶液校准配有酒类分析专用聚乙二醇石英毛细管柱的气相色谱仪,色谱峰面积相对标准偏差、检出限均满足检定校准技术要求.乙醇中甲醇标准溶液的色谱峰对称性差,甲苯中苯标准溶液的色谱响应值最低.乙醇中叔戊醇标准溶液是理想的聚乙二醇酒类分...     

质检总局发布多项仪器校准规范/检定规程

正前不久,质检总局发布《动态压力标准器检定规程》等58个国家计量技术规范,涉及多项仪器校准规范/检定规程:平板电泳仪校准规范、PM2.5质量浓度测量仪校准规范、流式细胞仪校准规范、全自动微生物定量分析仪校准规范、汽     

电导率仪电计与电导池配套检定时检定装置配置的探讨

根据JJF1059－1999《测量不确定度评定与表示》，JJG376－1985《电导仪试行检定规程》，经过测量不确定度分析。探讨了在进行电计与电导池配套检定时，由不同级别的国家电导率指标物质及配套设备组成的检定装置所适合检定的电导率仪，以及检定装置的最佳配置。     

试验箱温、湿度校准装置的研制

介绍试验箱温、湿度校准装置的模型建立,温、湿度传感器的选择及软硬件构成,利用温、湿度精密测量,多路信号输入,单片机控制等功能,实现装置的温、湿度多点校准。通过验证试验证明该装置测量准确可靠。     

一体化湿度校准装置的研制

介绍一体化湿度校准装置的原理、实现方法和性能特点。根据分流法原理研制湿度发生单元,根据露点法原理研制湿度控制单元,通过软硬件系统实现闭环控制,组成一体化的湿度校准装置。对其测量不确定度进行了评定,在露点–50~20℃范围内,扩展不确定度U=0.3℃(k=2);在露点–70~–50℃范围内,扩展不确定度U=0.5℃(k=2)。该装置具有自动化程度高、量值准确可靠、平衡时间短、便于移动或携带等特点,能够扩展分流法湿度发生器的应用领域。     

Characterizing zeta potential of functional nanofibers in a microfluidic device

The measurement of surface charge on nanofibers was achieved by characterizing zeta potential of the nanofibers via a newly developed device for streaming current measurement. Low flow rates were sufficient to generate detectable streaming currents in the absence of an externally applied voltage without damaging nanofiber samples. Zeta potential was calculated by using the Helmholtz-Smoluchowski equation and the measured streaming currents. Two acrylic plates were machined and assembled to form a microfluidic channel that is 150 μm high, 2.0mm wide, and 30 mm long. Two electrodes for the measurement of streaming currents were housed in the top plate. Two nanofibers of pure polyacrylonitrile (PAN) fibers and charged (TiO(2) incorporated) PAN fibers were prepared and characterized in the device. Monobasic sodium phosphate and dibasic sodium phosphate were used to prepare four different pH buffer solutions ranging from pH 5 to pH 8 in order to characterize the zeta potentials. The pure PAN nanofibers had negatively-charged surfaces regardless of pH. However, the zeta potentials of PAN/TiO(2) nanofibers changed from positive to negative at pH 6.5. The zeta potential measurements made on the nanofibers in this new microfluidic device matched with those of the powdered raw materials using a commercial Zetasizer.     

在线酸度仪校准装置的研制

为了提高在线酸度监测仪表的计量精度,使计量校准实现动态测量,研究了在线式酸度监测仪的校准方法,并根据校准方法研制了一种在线动态计量检定校准装置,该装置利用国家一级标准物质进行量值传递。整套装置模拟了在线酸度仪的工作状态,工作流速30－250mL／min,校准结果的不确定度为0．01pH,满足校准的要求。     

便携式湿度发生器的研制

介绍一种便携分流式湿度发生器的工作原理及研制过程。该便携式湿度发生器利用分流法湿度发生原理,采用微控制器和质量流量控制技术实现了自动发生不同流量、不同露点气体的功能,可为露点测试仪检定和校准提供动态标准湿度气体。通过验证试验证明,该装置测量准确可靠。     

A simple optical device for measuring free surface deformations of nontransparent liquids

In this paper, a novel optical device for measuring the deformation of liquid free surfaces is presented. The device employs a laser beam, which can be focused on any chosen location on the free surface. The key measurement is of the intensity of the beam reflected from a location on the free surface where the deformation exhibits a local extremum. The optics of the device is so designed as to measure a maximum intensity when the distance between the focusing lens and the selected point on the free surface is equal to the focal length, thus enabling a height measurement. The device is tested in ferrofluid pools where the height of the spikes of the normal field instability is measured. The simplicity of the suggested technique enables the fabrication of a quite cheap device for measuring surface deformation of nontransparent liquids, which provides good accuracy and reproducibility.     

Validation of a new measuring system for water turbidity field measurements

Turbidity is an essential parameter for describing water quality by direct and indirect impacts on fish, invertebrates and aquatic plants. Currently, environmental monitoring measurements are carried out with appropriate quality by accredited testing laboratories, but there is also a need for employing the third sector, i.e. citizens and voluntaries in environmental monitoring. A device called “Secchi3000” was developed as a low-cost and simple-to-operate tool so that water quality measurements can also be carried out by non-experts and citizens. The measurement using the new device is simple: The user fills the container with water and places the measurement structure in the container. The user takes a photograph with the camera on a mobile phone through a hole in the lid. The software sends the photograph to a server, which analyses the photographs automatically. Finally, the results are returned to the user’s mobile phone and stored on a database for further analysis. In this study, the measuring system for turbidity measurements in natural waters was validated. Validation included an estimation of the limit of quantification, investigations of the influence of water colour and illumination conditions on turbidity measurement values and the estimation of measurement uncertainty. A comparison of turbidity results obtained with the new device and laboratory instrument in natural water samples was carried out, and turbidity values obtained with different mobile phones were compared. According to the validation results, the new device was appropriate for the measurement of turbidity lower than 7 FNU (Formazine Nephelometric Unit). An algorithm applied for present turbidity calculations is not fully suitable for higher turbidities. For potential routine use, this is not a major problem, since most Finnish natural waters have turbidities lower than 7 FNU. For official monitoring purposes, the limit of the quantification needs to be lower than presently achieved (1.7 FNU). Although the present configuration of the Secchi3000 device is not yet fully suitable for official environmental monitoring, it will already enable the involvement of the third sector in water quality monitoring, and in this way, citizens’ observations could then serve at least as supplementary information for reporting and surveys.     

Multi-analyte miniature conductance biosensor

The fabrication and operation of a multi-analyte miniature conductance biosensor is described. The device responds to changes in the electrode double layer capacitance as the ionic strength is increased by the enzyme-catalysed generation of charged reaction products. Enzymes such as urease and l-asparaginase and a three-enzyme system consisting of urease, creatinase and creatininase were used to determine urea, l-asparagine and creatinine, respectively. Careful choice of suitable enzyme immobilization regimes led to device response times for the attainment of the steady state of the order of seconds. This fast response time allowed the construction of a flow cell with the incorporation of a urease-modified device for the continuous measurement of urea in flowing systems.     

熔点标准物质的定值

介绍凝固点下降薄层比较法测量熔点标准物质熔点的测量装置的构成与工作原理。用该装置对5种标准物质的凝固点或熔点进行了测量,给出了定值结果和不确定度。