酒石酸钾钠(分子式KNaC₄H₄O₆·4H₂O)也称酒石酸钠钾、罗氏盐或罗谢尔盐,是酒石酸钠与酒石酸钾形成的复盐。它为无色至蓝白色正交晶系晶体,可溶于水,微溶于醇,味咸而凉,水溶液呈微碱性,比重1.79,pH值6.8-8,熔点70-80°C,在热空气中稍有风化性。60°C时开始失去结晶水,215°C时完全失去结晶水变成无水盐。酒石酸钾钠分为D型和DL型两种:D型为无色透明晶体,在水中溶解度30℃时为100 mL中138.3 g,不溶于醇;DL型为白色细粒晶体,密度1.783 g/cm³,熔点100°C。酒石酸钾钠具有络合性,能在碱性溶液中与铜、铁、铅、铬等金属离子形成可溶性络合物。
理化性质酒石酸钾钠可用作缓泻剂、食品添加剂和压电元件。也可作为化学试剂用于配制菲林试剂、双缩脲试剂,并应用于制镜还原剂等。
参考质量指标美国食品化学法典(III):
企业标准 浙Q/HG079-81(电镀级):
粗制品通过加热溶解、活性炭脱色、再结晶等步骤制得成品。具体过程如下:
用于配制斐林氏溶液、双缩脲试剂,作为掩蔽剂和还原剂测定;食品添加剂;血清蛋白的生化检验;印刷工业中的制版、制镜;热水瓶工业中的还原剂;电镀工业中的络合剂;医药上的缓泻剂;电讯工业中制作晶体喇叭及话筒;化肥工业ADA脱硫剂等。
含量分析按GT-2方法测定,每mL 0.5 mol/L硫酸相当于酒石酸钾钠(C₄H₄KNaO₆·4H₂O)70.56 mg。
毒性无毒。GRAS(FDA,§184.1804,2000)。ADI:0-30 mg/kg(FAO/WHO,2001)。
用途在食品工业中用作焙粉,在印刷业用于制版和制镜;用于费林溶液、斑氏溶液的配制;作为压电元件。
This paper presents a diagnostic technique for the identification of two cracks of equal severity in a simply supported beam under flexural vibrations. The crack is simulated by a rotational spring connecting the two adjacent segments ofthe beam. The analysis is based on an explicit expression of the frequency sensi tivity to damage, and the damaged system is considered as a perturbation of the virgin system. By measuring the changes of the first three natural frequencies, it is possible to study the inverse problem—identification of crack location and severity. The inverse problem is ill-posed; namely, even by leaving symmetrical posi tions aside, cracks with different severity in two sets of different locations can produce identical changes in the first three natural frequencies. Numerical results show that if the natural frequencies used as data in iden tification are affected by errors relatively small with respect to the frequency-induced changes, then damage identification leads to satisfactory results.