人造芥子油中异硫氰酸烯丙酯与硫氰酸烯丙酯的气相色谱分析

采用２ｍ×３ｍｍ玻璃柱，涂布０．５％ＥＧＡ的８０～１００目ＧａｓｃｈｒｏｍＱ为固定相，以异辛醇为内标物，分析芥子油中异硫氰酸烯丙酯与硫氰酸烯丙酯异构体。该方法既可用于人造芥子油的含量分析，也可用于市售芥子油的质量鉴定。     

A new procedure for determination of nickel in some fake jewelry and cosmetics samples after dispersive liquid–liquid microextraction by FAAS

A new, simple and cheap dispersive liquid–liquid microextraction (DLLME) procedure was optimized for the preconcentration of trace amounts of Ni(II) as a prior step to its determination by flame atomic absorption spectrometry (FAAS). It is based on the microextraction of nickel, where appropriate amounts of the extraction solvent (CHCl₃), disperser solvent (ethanol) and chelating agent, name 5‐[(Z)‐isoxazol‐3‐yl‐diazenyl]‐2‐methyl‐quinolin‐8‐ol (MMD), were firstly synthesized/characterized and used. Various parameters that affect the extraction procedure such as pH, centrifugation rate and time, the chelating agent (MMD) concentration and sampling volume on the recovery of Ni(II) were investigated. The preconcentration of a 20 ml sample solution was thus enhanced by a factor of 80. The resulting calibration graph was linear in the range of 0.24–10 mg L⁻¹ with a correlation coefficient of 0.9998. The limit of detection (3 s/b) obtained under optimal conditions was 1.00 μg L⁻¹. The relative standard deviation for certified reference material determinations was 1.2%. The accuracy of the method was verified by the determination of Ni(II) in the certified reference material of wastewater (Waste water CWW TMD). The proposed procedure was successfully applied to the determination of Ni(II) in some fake jewelry and cosmetics samples.     

人造聚晶翡翠宝石

 综述了翡翠宝石的人工合成的进程及各种实验结果，给出了6×8MN六面顶高压装置的压力和温度工作曲线，对比了两面顶高压装置及六面顶高压装置上合成翡翠宝石的优缺点及解决办法，并做了合成高品级翡翠宝石的尝试。     

Positioning of new brands in an experiment

This paper deals with an experimental investigation of positioning new brands. For this purpose, a management game was carried out with students. The brands introduced in the cause of the game were analysed in respect to their positions in a two-dimensional feature space. We try to find out which of the two strategies, niche policy and imitation, is more frequently used in complex decision situations and if there is a difference in profits. Furthermore, we want to find out, whether differences of prices and advertising exist in our experiment depending on the positioning strategy used.     

反相高效液相色谱法测定陶瓷饰品中六价铬的溶出量

提出了柱前衍生反相高效液相色谱法测定陶瓷饰品中六价铬溶出量的方法。采用人工汗液萃取陶瓷饰品,用1,5-二苯卡巴肼与萃取液中的六价铬在酸性条件下进行衍生反应,衍生物在Waters SunFire ODS C18色谱柱上分离,以pH 2.5的10mmol·L-1磷酸二氢钾缓冲溶液和丙酮为流动相进行梯度洗脱,于波长540nm处进行测定。六价铬的质量浓度在5.0~200.0μg·L-1范围内与峰面积呈线性关系,相关系数为0.999 1,检出限(3S/N)为0.037μg·L-1。空白(实际样品)的加标回收率在97%~101%之间,测定值的相对标准偏差在1.9%~3.2%之间。     

原子吸收光谱法测定首饰镍释放量的不确定度评定

通过对原子吸收光谱法（AAS）测定首饰中镍释放量不确定度的评定,建立了该分析过程的相应数学模型,对数学模型中各个参数进行不确定度来源分析。研究结果表明:配制标准液以及标准工作曲线拟合线性方程是不确定度的主要来源。通过计算,首饰中镍释放量的合成标准不确定度为3.02×10-3,当包含因子k=2,置信水平为95%时,扩展不确定度为 6.04×10-3 μg/(cm2·week）。     

Blind alleys and fruitful pathways in the comparative study of cultural cognition

A mere few decades ago, culture was thought a unique human attribute. Evidence to the contrary accumulated through the latter part of the twentieth century and has exploded in the present one, demonstrating the transmission of traditions through social learning across all principal vertebrate taxa and even invertebrates, notably insects. The scope of human culture is nevertheless highly distinctive. What makes our cultural capacities and their cognitive underpinnings so different? In this article I argue that in behavioural scientists' endeavours to answer this question, fruitful research pathways and their ensuing discoveries have come to exist alongside popular, yet in the light of current empirical evidence, highly questionable scenarios and even scientific blind alleys. I particularly re-evaluate theories that rely on the centrality of a supposed uniquely human capacity for imitative copying in explaining the distinctive capacity for massive cumulative cultural evolution (CCE) in our species. The most extreme versions of this perspective suffer logical incoherence and severe limits on scientific testability. By contrast the field has generated a range of rigorous observational and experimental methodologies that have revealed both long-term cultural fidelity and limited forms of CCE in non-human species. Attention now turns to directly investigating the scope, limits and underlying cognition of non-human versus human CCE, with a broader approach to factors additional to cultural transmission, notably the role of invention, innovation and evolved motivational biases underlying the scope of CCE in the species studied.     

气相色谱―质谱法测定仿真饰品中磷酸酯类增塑剂含量

建立了仿真饰品中6种磷酸酯类增塑剂含量的气相色谱―质谱测定法。对提取方法、色谱条件及质谱参数进行了研究。结果表明,采用正己烷/丙酮(体积比1∶1)微波萃取样品35 min可获得良好的提取效果。所建立的微波萃取―气相色谱―质谱法的定量限为1～2.5 mg/kg,在1～2个数量级浓度范围内,线性相关系数R2在0.999以上,在三个添加水平下回收率在86.63%～98.13%之间。对市售9种塑料仿真饰品的测定结果表明磷酸酯的存在风险极低。     

仿真饰品中镍释放量测定能力验证的组织与实施

为了了解我国仿真饰品中镍释放量检测能力的整体水平,中国国家认证认可监督管理委员会(CNCA)组织了"CNCA–12–B07仿真饰品中镍释放量的测定"能力验证项目,该项目共有来自12个省市、特别行政区的38家实验室参加。镍释放量主要采用GB/T 19719–2005与EN 1811:2011进行检测,对检测结果采用稳健(Robust)统计方法分析。结果显示,第1次测试结果合格率为89.5%。     

四氢叶酸辅酶参与的酶催化—碳单元转移反应及其人工模拟进展

简要介绍了生物体系中酶催化的一碳单元转移反应以及四氢叶酸辅酶的结构和作用,综述了一碳单元转移反应的人工模型进展,展望了上述反应的理论研究方法及前景。