
【国外标准】 Standard Test Method for Purity by Differential Scanning Calorimetry
本网站 发布时间:
2024-02-28
开通会员免费在线看70000余条国内标准,赠送文本下载次数,单本最低仅合13.3元!还可享标准出版进度查询、定制跟踪推送、标准查新等超多特权!  
查看详情>>

适用范围:
5.1 The melting temperature range of a compound broadens as the impurity level rises. This phenomenon is described approximately by the van’t Hoff equation for melting point depressions. Measuring and recording the instantaneous heat flow into the specimen as a function of temperature during such a melting process is a practical way for the generation of data suitable for analysis by the van’t Hoff equation.5.2 The results obtained include: sample purity (expressed as mole percent); enthalpy of fusion (expressed as J/mol); and the melting temperature (expressed in Kelvin) of the pure form of the major component.5.3 Generally, the repeatability of this test method decreases as the purity level decreases. This test method is ordinarily considered unreliable when the purity level of the major component of the mixture is less than 98.5 mol % or when the incremental enthalpy correction (c) exceeds 20 % of the original detected enthalpy of fusion.5.4 This test method is used for quality control, specification acceptance, and research.1.1 This test method describes the determination of purity of materials greater than 98.5 mole percent purity using differential scanning calorimetry and the van’t Hoff equation.1.2 This test method is applicable to thermally stable compounds with well-defined melting temperatures.1.3 Determination of purity by this test method is only applicable when the impurity dissolves in the melt and is insoluble in the crystal.1.4 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard.1.5 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety, health, and environmental practices and determine the applicability of regulatory limitations prior to use.1.6 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.
标准号:
ASTM E928-19
标准名称:
Standard Test Method for Purity by Differential Scanning Calorimetry
英文名称:
Standard Test Method for Purity by Differential Scanning Calorimetry标准状态:
Active-
发布日期:
-
实施日期:
出版语种:
- 推荐标准
- ASTM E866-23 Standard Specification for Corrosion-Inhibiting Adhesive Primer for Aluminum Alloys to Be Adhesively Bonded in Honeycomb Shelter Panels
- ASTM E867-23 Standard Terminology Relating to Vehicle-Pavement Systems
- ASTM E870-82(2019) Standard Test Methods for Analysis of Wood Fuels
- ASTM E871-82(2019) Standard Test Method for Moisture Analysis of Particulate Wood Fuels
- ASTM E872-82(2019) Standard Test Method for Volatile Matter in the Analysis of Particulate Wood Fuels
- ASTM E874-19 Standard Practice for Adhesive Bonding of Aluminum Facings to Nonmetallic Honeycomb Core for Shelter Panels
- ASTM E875-20 Standard Practice for Evaluation of Fungal Control Agents as Preservatives for Aqueous-Based Products Used in the Paper Industry
- ASTM E877-21 Standard Practice for Sampling and Sample Preparation of Iron Ores and Related Materials for Determination of Chemical Composition and Physical Properties
- ASTM E878-20 Standard Test Method for Determination of Titanium in Iron Ores and Related Materials by Diantipyrylmethane Ultraviolet Spectrophotometry
- ASTM E879-20 Standard Specification for Thermistor Sensors for General Purpose and Laboratory Temperature Measurements
- ASTM E88-11(2017) Standard Practice for Sampling Nonferrous Metals and Alloys in Cast Form for Determination of Chemical Composition
- ASTM E882-10(2016)e1 Standard Guide for Accountability and Quality Control in the Chemical Analysis Laboratory
- ASTM E887-21 Standard Test Method for Silica in Refuse-Derived Fuel (RDF) and RDF Ash
- ASTM E889-82(2023) Standard Test Method for Composition or Purity of a Solid Waste Materials Stream
- ASTM E90-23 Standard Test Method for Laboratory Measurement of Airborne Sound Transmission Loss of Building Partitions and Elements