近10多年来，国家一级标准物质的研制量一直保持占全国标准物质总量的12％左右。至1996年，我国已发布的国家一级标准物质的总量为881种，其中核标准物质有102种，占全国总品种的11．6％。世界各国的标准物质，目前已有10000多种，其中美国有10O0多种。科学与研制工艺、分析技 In the past 10 years or more, the amount of research and development of national-level reference materials has remained at 12% of the total national standard. By 1996, China had released 881 kinds of standard substances at the national level, of which 102 were nuclear standards, accounting for 11.6% of the total national product. There are over 10,000 kinds of standard substances in various countries in the world, among which more than 10O0 are in the United States. Science and Technology, Analysis Technology