Vol.5 No.1 2012
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Research paper : Analysis of synthetic approaches described in papers of the journal Synthesiology (N. Kobayashi et al.)−44−Synthesiology - English edition Vol.5 No.1 (2012) the three requirements: 1) the establishment of national metrology standard traceable to the international standard (SI), 2) the maintenance of international consistency (through internationally recognized measurement method and international comparison), and 3) the construction of the traceability system that links AIST, the accredited calibration laboratories, and the end users. Requirement 1 corresponds to the “technological synthesis,” requirement 3 to the “synthesis for introduction to society,” and requirement 2 links the two. Two examples of the R&D for physical and chemical standards are shown below (Fig. 8). An example of the physical standard is the research of the traceability system for the temperature standard to calibrate the thermocouple in the temperature range of 1000 °C ~ 1550 °C by Arai et al.[37] The temperature measurement in this range is particularly important in the industries where temperature management is crucial, including the materials industry such as iron and steel, as well as the parts manufacturing and semiconductor process industries where heat treatment is necessary. The thermocouple is a thermometer used most frequently in such industrial sites, but the reliability of measurement was not very high, and the establishment of the metrology standard and the organization of a traceability system had to be done quickly. The national metrology standards in this temperature range are the fixed points of temperature of pure metals. Specifically, they are the freezing point of silver (961.78 °C), freezing point of copper (1084.62 °C), and melting point of palladium (1553.5 °C). These temperature fixed points were determined by the Conférence Générale des Poids et Mesures (CGPM) comprised of the representatives of the member countries of the Convention du Mètre, based on the thermodynamic temperature scale [requirement 1]. For international recognition, international comparison (APMP-T-SI-4) was conducted with the metrology institutes of various countries, and AIST’s calibration values and low uncertainty achieved the highest reliability among the participating institutes [requirement 2]. To construct the traceability system, a transfer standard that can deliver precise standard value between AIST and the calibration labs was necessary, and stability and sturdiness were required for such a transfer standard. Therefore, the highly reliable platinum-palladium thermocouple and the R-type thermocouple were developed to fulfill such conditions [requirement 3]. In this process, it was newly found that appropriate heat treatment contributed greatly to the stability of the thermocouple. Also, the application of the eutectic point as the fixed temperature point, an original technology developed by AIST, is spreading to the metrology institutes of the world, and in the near future, the provision of temperature scale with even higher reliability is expected.The example of the chemical standard is the study of the development of the reference material to guarantee the reliability of analysis done by testing institutes for the hazardous materials (such as residual harmful substances and agrichemicals) in the food and environment that are directly linked to the safety of the Japanese citizens, by Ihara et al.[38] The quantitative NMR method was developed since there were over a thousand types of hazardous material in the food and environment that have been targeted for regulation by law, and there was a need to develop and analyze numerous reference materials quickly. This is an innovative method in which the calibrations of the multiple types of practical reference material are done by a minimum number of standards, rather than the conventional method where the reference materials were prepared for each chemical substance.The NMR measurement method is normally used to detect unknown substances or to identify molecular structures, Fig. 8 Strategic selective synthesis in the metrology/measurement science fieldTransfer standard; national standard reference material, transfer substanceCCQM-CIPM, APMP-T-SI-4Temperature fixed point group, cryoscopyBridge「Synthesis for social introduction」 「Technological synthesis」③Construction of traceability system①SI traceableThe outlet (to deliver highly reliable metrology standard to the end user) is clear. The scenario is made to achieve this objective, and the necessary elemental technologies are selected and synthesized.②International consistencyThree requirements that regulate the R&D for metrology standardStatus in society and industryStatus of accredited calibration laboratoriesNational policy, policy of regulating authoritiesEstablishment of national metrology standardExecution of standard provisionParticipation in international comparisonInternationally agreed measurement method

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