浅谈环境监测站如何实施计量认证

建立以质量为核心的管理体系,对监测的全过程实施质量控制。通过内部审核,发现质量体系实施中的问题;通过管理评审,由技术负责人确认问题,做出决策;再通过纠正措施和预防措施来解决问题,从而形成一个不断实施质量改进的环境监测站自我完善机制。     

环保系统计量认证的工作程序

为帮助申请国家级计量认证的环保机构开展工作，介绍了环保系统计量认证的依据、认证机构、评审准则以及工作程序，并就计量认证的申请与受理程序、准备工作、评审步骤、整改与上报材料以及审批发证程序进行了阐述。     

The development of a microscale strain measurement system applied to sheet bulge hydroforming

Micro and multiscale sheet metal forming processes represent new and attractive solutions to many manufacturing problems. However, evaluating the strains in these products is a difficult endeavor. Larger organizations are utilizing commercially available microscale digital image correlation systems to measure the strains in microscale parts or on macroscale parts with critical microscale features. The cost of these strain measurement systems is preventing smaller research and development organizations from entering this challenging area or they are forgoing the ability to determine strains. The present paper describes the development of a method for creating microscale grids and measuring strains on microscale parts or microscale locations on larger parts. The method developed was able to measure true strains up to 0.618 for square grids that are 127 μm measured from center-to-center. Microscale strains resulting from sheet bulge hydroforming experiments using 11 mm, 5 mm, and 1 mm diameter dies were evaluated and material properties of the sheet metal were estimated based upon the strains measured in conjunction with FEA simulations and compared to analytical solutions and microscale tension tests. The material properties determined using the strains and FEM approach were consistent with the other methods.     

水样中铵氮测量的不确定度评定

通过对铵氮测定过程的分析,找出了影响测定结果的各个分量。影响测定结果的分量主要有:标准溶液、回归曲线、试样平行试验、纳氏试剂分光光度法、分光光度计,取样等。在此基础上对测量的不确定度进行了评定,并按照计量技术规范,给出了标准的表示法。