铬污染土壤中Cr6+的测定

通过研究土壤中的Cr^6 的提取测定方法，结果表明，用0．4mol/L KCl为提取剂，离心分离提取液，可简单、快速、准确地测定土壤中的Cr^6 。所建立的方法适用于北方偏碱性土壤。     

铁氰化钾分光光度法测定单宁的适用性

分析了ＦｅＣｌ３—Ｋ３Ｆｅ（ＣＮ）６分光光度法测定植物单宁的适用性。结果表明，在ｐＨ＜２．２时的酸性介质中单宁－ＫＦｅ［Ｆｅ（ＣＮ）６］最大吸收峰在６８０～７２０ｎｍ之间，绝大多数情况下吸收峰在６９５ｎｍ处，比色液单宁浓度在０～８０μｇ·ｍｌ－１时未形成沉淀前，遵守朗伯—比耳定律。时间变异系数每分钟±０．０５％，回收率９４．７％～１０５．２％，相对误差１．２％～５．３％。该方法受在酸性条件下能将Ｆｅ３＋还原为Ｆｅ２＋的物质和形成沉淀的物质干扰。测定结果与靛红—高锰酸钾滴淀法相接近。     

TDZ和6-BA对大豆子叶节再生体系中丛生芽诱导的效应

以栽培大豆品种‘Jackson’为试材,用萌发5 d的子叶节作外植体,接种于不同激素配比的萌发培养基和诱导培养基中,分析和比较TDZ(噻二唑苯基脲)和6-BA(6-苄基腺嘌呤)单独和复配使用时对大豆子叶节再生体系中丛生芽的诱导效应,并对其优化组合进行了筛选。结果表明:在种子萌发培养基中,0.5 mg·L-16-BA或TDZ单独使用时,前者能使丛生芽诱导率达到75.56%,诱导效应好于后者,但每个子叶节出芽数低于后者。在诱导培养基中,0.5 mg·L-16-BA和1.0 mg·L-1TDZ复配使用时,丛生芽诱导率最高且每个子叶节出芽数最多,分别为84.75%和3.04。     

Insecticide detoxification indicator strains as tools for enhancing chemical discovery screens

BACKGROUND: Insecticide discovery screens carried out on whole organisms screen for potency resulting from chemical activity at the target site. However, many potentially insecticidal compounds are naturally detoxified in vivo and do not make it to the target site. It is hypothesised that insect strains with their xenobiotic detoxification machinery compromised could be used to identify such compounds that normally fail to show up in screens; these compounds could then be more rationally designed to increase their bioavailability. This strategy was tested with transgenic Drosophila lines with altered expression of Cyp6g1 and Dhr96. RESULTS: It was observed that Cyp6g1 knockdown transgenic lines have increased susceptibility to the test compound imidacloprid, while Dhr96 knockdown transgenic lines are resistant. Evidence was found for a systemic response to xenobiotic exposure, uncovered by piperonyl butoxide treatment and by gene expression profiling. Sex-specific gene expression regulated by DHR96 was also observed. CONCLUSION: The results confirm that this approach to chemical discovery could identify compounds that escape traditional screens. The complexity of the system means that a panel of single and multiple gene knockdown transgenic lines may be required. Copyright © 2011 Society of Chemical Industry     

气相色谱法测定油茶籽油中六号溶剂残留量的不确定度评定

依据《GB/T 5009.37-2003》,用气相色谱法测定油茶籽油中六号溶剂的残留量,并按照《JJF 1059-1999》的规定,对该检验过程进行不确定度评定。结果表明:气相色谱法测定油茶籽油中六号溶剂残留量的测量不确定度,在各个不确定度量值中,标准曲线拟合是测量过程中不确定度的主要来源,标准物质与样品称量所产生的不确定度则可忽略不计。     

苏丹六区输油管道工程EPCC项目设计要点

苏丹六区输油管道工程EPCC项目具有典型的国际EPCC项目特点,其项目设计分为概念设计、基础设计和详细设计3个阶段。项目启动阶段的设计工作主要包括招投标文件整理、合同解读、合同内容变更、标准规范确认和设计资料收集。详细描述了EPCC项目应提交设计文件的分类和编制要求,并从专业协调、部门结合及与业主沟通方面总结了设计管理工作的重点内容,从设计进度控制和设计成本控制两个方面说明了设计控制的具体工作,详述了设计现场服务的主要工作内容以及竣工资料的编制范围和编制依据。     

6%烟嘧磺隆SC防除玉米田杂草的效果

采用6%烟嘧磺隆SC等除草剂对上海地区玉米田杂草进行田间防除试验。结果表明,在玉米4叶期左右,6%烟嘧磺隆SC 900～1 200 g/hm2兑水45 kg进行茎叶喷雾,能有效防除玉米田马唐、牛筋草、刺苋、凹头苋、马齿苋等一年生杂草。