不同光质对矮生黄瓜幼苗内源激素的影响

为研究不同光质对矮生黄瓜幼苗内源激素的影响,进而对矮生黄瓜的矮化机理进行初步探讨。通过对蔓生黄瓜129和矮生黄瓜D0462覆盖白、蓝、红色滤膜获得不同光质,利用高效液相色谱法测定不同光质处理后的叶片和下胚轴中赤霉素(GA3)、吲哚乙酸(IAA)和脱落酸(ABA)的含量。结果表明,蓝光处理后,D0462叶片和下胚轴中GA3、IAA含量显著或极显著低于白光和红光,而ABA含量极显著增高;D0462的GA3、IAA含量极显著低于129,ABA含量极显著高于129;D0462下胚轴中GA3/ABA、IAA/ABA、(GA3+IAA)/ABA的比值极显著低于白光,同时也极显著低于129。综合结果可知,蓝光可能是导致矮生黄瓜D0462矮化的原因。     

Determination of Naringin Content in Peel of Guangxi Citrus maxima (Burm.) Merr by HPLC

[Objectives]To establish a method for determining the naringin content in the peel of Guangxi Citrus maxima(Burm.)Merr.[Methods]The high performance liquid chro...     

Interference elimination of PCB and its ramification in determining trace PBBs/PBDEs by GC/MS

The normal method to determine the trace brominated flame retardants such as polybrominated biphenyls (PBBs) and polybrominated diphenylethers (PBDEs) contained in the electronic and electrical products is gas chromatography/mass spectrometry (GC/MS). However, the method is based on the determinations of the persistent organic pollutants (POPs) such as polychlorinated biphenyls (PCBs), and polychlorinated naphthalene (PCNs) etc. The interferences of those compounds are inevitable. Therefore, in order to overcome this problem, two methods e.g. 1) The combination use of gas chromatography negative ion chemical ionization mass spectrometry (GC-NICI-MS) and gas chromatography-electron impact-mass spectrometry (GC-EI-MS) is employed, 2) a matrix solid-phase dispersion (MSPD) method with YMC ODS-C18 as carrier is developed. The result show that, by the former method, the brominated isomers or ramifications are distinguished remarkably from other halogen compounds because that anion fragment retention peaks of ［Br］-, ［HBr2］- and molecule chain fragment retention peaks of ［M+2］+,［M+4］+,［M+6］+,［M+8］+ are observed simultaneously, and thus the selectivity to determine bromine-containing retardant flames is greatly improved. Using the latter method, the gas chromatographic peaks of multiple polychlorinated biphenyls and polybrominated diphenylethers can be efficiently separated. Thus provides a project to solve interferences of POPs in brominated flame retardants’ determinations. The standard addition experimental results of 10 kinds of BDEs/PCBs belonging to 8 sorts of electronic and electrical equipment show this method has a high precision and reliability due to 60%～98% recovery and <9.5% relative error, which meet the needs regulated by the IEC Commission. It provides a technical support for electronic and eletrical industries in China to further comply with RoHS directive.     

气相色谱法测定稻谷中三环唑的不确定度分析

采用气相色谱法对稻谷中三环唑残留量的不确定度进行评估。根据JJF 1135—2005化学分析测量不确定度评定和JJF 1059.1—2012测量不确定度评定与表示中的相关规定,对测定过程中可能引入的不确定度进行分析和评估,建立了测定稻谷中三环唑残留量不确定度评定的数学模型,分析不确定度的主要来源,并将各分量进行合成。得出当稻谷中三环唑的量为0.262mg/kg时,其扩展不确定度为0.020 mg/kg (k=2)。     

基于液-液萃取机理的新型环境样品前处理方法研究进展

新型环境样品前处理技术已经逐步取代传统液-液萃取。液相微萃取、液膜萃取和逆流色谱技术均是集采样、萃取和浓缩于一体的环境友好型环境样品前处理技术。液相微萃取、液膜萃取实质上是微型化的液-液萃取;逆流色谱结合了液液萃取和分配色谱的优点,是一种新型色谱分离技术。3种技术均对环境样品中的痕量/超痕量污染物质有高效的富集、净化效果。笔者综述了液相微萃取、液膜萃取和逆流色谱技术的优缺点及在环境样品前处理中的应用。     

超声提取—气相色谱法测定油脂中胆固醇

建立了毛细管气相色谱法测定油脂中胆固醇含量的方法,改进了油脂皂化方法以及皂化完成后使用分液漏斗提取胆固醇过程中容易产生乳化、操作复杂且比较耗时的缺点,采用超声波提取胆固醇,优化了样品前处理条件.结果表明,该法在0.002mg/mL～0.500mg/mL范围呈线性(r=0.9997),检出限为20mg/kg,RSD=1.104％,回收率在81.3％～93.8％之间.     

Flash chromatography on cartridges for the separation of plant extracts: Rules for the selection of chromatographic conditions and comparison with medium pressure liquid chromatography

Empirical rules for the selection of chromatographic conditions on flash chromatography cartridges were developed, with an emphasis on gradient mode. These rules were then tested with separation of extracts from important medicinal plants including Curcuma xanthorrhiza, Piper nigrum and Salvia milthiorrhiza. Sepacore® cartridges enabled a good separation of compounds with a broad range of polarity, as typically found in plant extracts. The chromatographic resolution remained, however, lower than that achieved on classical columns packed with material of smaller particle size. For poorly soluble extracts, solid introduction gave better results than liquid injection.     

猪凝血酶的亲和层析纯化及其酶原的激活研究

采用柠檬酸钡作吸附剂、ＥＤＴＡ溶解的方法从猪血浆提取凝血酶原，建立了凝血酶原激活的简单方法。并以环氧氯丙烷活化的Ｓｅｐｈａｒｏｓｅ４Ｂ为载体，采用１－乙基－３－（３－二甲氨丙基）碳二亚胺进行肝素的固定化，将固定化肝素用于猪凝血酶的亲和层析纯化。结果表明，通过一步亲和层析将猪凝血酶粗品提纯了８．２倍，获得了比活超过１１００Ｕ／ｍｇ的凝血酶，收率为６０％。     

除草剂阿特拉津的气相色谱法残留分析

使用ＧＣ－９Ａ气相色谱仪附氮磷检测器测定了阿特拉津在玉米植株及其土壤中的残留情况，检测极限０．０５ｎｇ，变异系数小于１％。     

维生素C的新型高效液相色谱分析

本文研究了维生素C的新型高效液相色谱分析方法。以超纯水为流动相,流动相的速度为1.0ml/min,紫外检测波长为267nm,柱温在25～30℃的条件下分析维生素C,结果具有良好的线性关系,其相关系数R2=0.9994;相对标准偏差等于0.74%。所建立的方法简单、快速、准确率高,适于维生素C含量的分析研究。