猪牛羊可食性组织中阿苯达唑残留检测方法研究

 建立了动物可食性组织中阿苯达唑及其主要代谢物亚砜和砜残留检测的高效液相色谱(HPLC)法。组织中3种残留物分别用乙醚、乙腈和正己烷提取和净化,氮气吹干,甲醇溶解,HPLC测定,内标法定量。该方法可检出猪、牛、羊肌肉、肝脏、肾脏组织中阿苯达唑、砜和亚砜的最低限量均为16.6 μg·kg-1,在16.6μg·kg-1浓度时,动物组织中阿苯达唑、砜和亚砜的平均回收率分别为7 5％～99％、8 0％～9 0％和61％～91％,日间变异系数均小于20％。用所建方法,对市场上动物可食性组织进行抽样检测,共抽检5 4份样     

氯化苦在土壤中的消解动态和残留量检测研究

[目的]研究氯化苦在土壤上的残留分析方法及在土壤中的消解动态和最终残留量。[方法]采用气相色谱法测定氯化苦在土壤中的残留,用石油醚对土壤样品进行超声波提取,毛细管柱色谱分离,电子捕获检测器进行测定,进行了3种添加浓度的回收率试验并进行实际样品检测。[结果]氯化苦的的最低检出限（LOD）为0.008mg／kg,土壤中最低检出浓度（LOQ）为0.020mg／kg,回收率89.5％—111.1％,变异系数为3.6％—7.2％,均在农药残留测定所允许的范围内。同时在0.008—2.000mg／L浓度范围内峰面积值与氯化苦浓度线性关系良好,且线性范围较宽,适合测定土壤中不同浓度水平的氯化苦。氯化苦的消解很快,在土壤中的半衰期为5.5d。[结论]该分析方法操作简单、快速,定量准确,可有效地测定土壤中氯化苦含量。     

超高效液相色谱法-串联质谱法测定牛奶中的氯霉素残留

应用超高效液相色谱-串联质谱法建立了牛奶中的氯霉素的检测方法。样品经乙酸乙酯提取后,用正已烷除脂,经C18固相萃取小柱富集纯化后,以C18反相柱为分析柱,乙腈-0.5mmol/L乙酸铵溶液为流动相,采用电喷雾负电离源(ESI-),多反应监测模式(SRM),用内标法定量检测。该方法提高了检测灵敏性和分析结果的可靠性,能够适应大规模样品的分析要求。     

牛奶中克林霉素残留量的反相高效液相色谱测定方法

目的:研究建立牛奶中克林霉素残留量的反相高效液相色谱测定方法。方法:样品用水相提取,离心分离,经C18固相萃取柱净化,在205nm波长下用二极管矩阵检测器检测。色谱柱为Agilent ZORBOX SBC18柱(4.6mm×250mm,5μm),以0.025mol/L磷酸二氢铵溶液∶甲醇(55∶45,V/V)为流动相,流速1.0mL/m in。结果:克林霉素浓度在1.0~10.0μg/mL范围内与峰面积呈良好的线性关系,平均回收率为80.3%~93.9%,变异系数为1.23%~3.47%,最低检测限为0.5μg/mL。结论:本方法简便、快速、准确。     

SPE-GC-μECD测定蔬菜中6种三唑类农药的残留量

[目的]建立一种蔬菜中6种三唑类农药残留的气相色谱检测方法。[方法]蔬菜样品用乙腈提取,盐析分层后上清液经固相萃取柱净化,用丙酮＋正己烷（20＋80）洗脱,采用带微电子捕获检测器的气相色谱仪测定其中腈菌唑、戊菌唑、三唑酮、苯醚甲环唑、丙环唑、三唑醇6种三唑类农药的残留量。[结果]方法的平均加标回收率范围为72．90％-98．80％,相对标准偏差范围为1．18％～9．88％。6种三唑类农药检测限范围为0．010-0．210mg／kg。[结论]该方法的建立为蔬菜中腈菌唑、戊菌唑、三唑酮、苯醚甲环唑、丙环唑、三唑醇6种三唑类农药残留的检测提供了参考。     

中心组合设计法优化马铃薯薯渣固态发酵工艺

为优化马铃薯薯渣固态发酵工艺,选择发酵温度、湿度和发酵时间为自变量,产品粗蛋白含量为因变量,采用中心组合设计的方法,研究各自变量及其交互作用对产品粗蛋白含量的影响。利用SAS6.0和响应面分析相结合的方法,模拟得到二次多项式回归方程的预测模型,并确定最佳发酵条件为:温度29.63℃,湿度73.86%,发酵时间54h。     

6种有机磷农药分离及水中残留高效薄层析测定方法研究

[目的]比较有机磷农药的分离方法,用高效薄层色谱测定农药在水中残留。[方法]采用高效薄层析技术AMD和双槽展缸上行展开方式分离水中辛硫磷、毒死蜱、双硫磷、甲基异柳磷、喹硫磷和三唑磷6种有机磷农药,并对自来水中4种有机磷残留的测定方法进行研究。[结果]两种展开方式均能很好分离6种农药。AMD展开Rf值分布范围较窄（相差0.34）,双槽展缸上行展开Rf值分布范围较宽（相差0.76）;AMD多步展开检测灵敏度较双槽展缸上行展开低。采用双槽展缸上行展开薄层色谱法检测水中有机磷农药残留,添加回收率在86.05%-109.80%之间,添加回收率、变异系数均满足农药残留分析的要求。[结论]该研究中,双槽展缸上行展开表现出灵敏度较高、操作简便、分析速度快的特点。     

Soil and residue management effects on arable cropping conditions and nitrous oxide fluxes under controlled traffic in Scotland 1. Soil and crop responses

Soil compaction can affect crop growth and greenhouse gas emission and information is required of how both these aspects are affected by compaction intensity and weather. In this paper we describe treatments of compaction intensity and their effects on soil physical conditions and crop growth in loam to sandy loam cambisol soils. Soil conditions and crop performance were measured over three seasons in a field experiment on soil compacted by wheels on freshly ploughed seedbeds. Ploughing buried the chopped residues of the previous crop. After ploughing, traffic was controlled such that the experimental plots received wheel traffic only as treatments. The overall objective was to discover how the intensity and distribution of soil compaction just before sowing influenced crop performance, soil conditions and emissions of nitrous oxide. Compaction treatments were zero, light compaction by roller (up to 1 Mg m⁻¹) and heavy compaction by loaded tractor, (up to 4.2 Mg). The experiment was located at Boghall, near Edinburgh (860 mm average annual rainfall) for the first two seasons under spring and winter barley (Hordeum vulgare L.) and in a drier area at North Berwick (610 mm average annual rainfall) for the third season under winter oil-seed rape (Brassica napus L.). Heavy compaction in dry soil conditions had little effect on crop growth. However, in wet conditions heavy compaction reduced air porosity, air permeability and gas diffusivity, increased cone resistance and limited winter barley growth and grain yield. Heavy compaction in wet conditions reduced winter barley yields to 7.1 Mg ha⁻¹, in comparison to 8.8 Mg ha⁻¹ in the zero compaction treatment. The compaction status of the top 15 cm of soil seemed to be particularly important. Loosening of the top 10 cm of soil immediately after heavy compaction restored soil conditions for crop growth. However, zero seed bed compaction gave patchy and uneven crop emergence in dry conditions. Both zero and light compaction to a target depth of 10 cm gave similar crop productivity. Maintenance of a correct compaction level near the soil surface is particularly important for establishment and overwintering of barley and oil seed rape.     

土壤中拟除虫菊酯类残留农药的气相色谱测定方法研究

建立了土壤中氯氰菊酯、氰戊菊酯和溴氰菊酯的提取、净化以及毛细管气相色谱的测定方法。运用石油醚-丙酮（P／P，2：1）混合溶剂提取，用氟罗里硅土进行层析净化，60ml石油醚／乙酸乙酯（V／V，9：1）进行洗脱，电子捕获-气相色谱测定，单点外标法定量。实验表明：土样中添加0．08mgkg^-1的氯氰菊酯、氰戊菊酯和溴氰菊酯3种农药混标时，方法回收率为89．67％～90．62％，添加0．40mgkg^-1时．方法回收率为91、07％～93．02％；操作中相对标准偏差（RSD）为2．02％～3．70％，最小检出量可达1．00pg。在检测色谱精密度实验中，5次测定3种农药混标，相对标准偏差（RSD）为1．37％～2．88％。实验表明，该法具有灵敏度高、操作简便、净化效果好、重现性好等特点。     

我国主产烟区烟田土壤有机农药残留状况研究

为摸清我国主产烟区烟田土壤农药残留状况,从全国13个主要植烟省的代表性植烟县市采集了431个土壤样品,采用气相色谱法测定分析了土壤中有机氯和有机磷农药残留。结果表明:六六六及滴滴涕含量均未超标,有机磷类农药含量均较低。六六六检出率为100%,含量范围为1.01~10.74μg/kg,平均为2.80μg/kg;滴滴涕检出率为100%,含量范围为0.18~410.88μ.g/kg,平均为15.44μg/kg;敌敌畏检出率为97.1%,含量范围为ND~2.01μg/kg,平均为0.27μg/kg;乐果检出率为63.6%,含量范围为ND~1.77μg/kg,平均为0.18μg/kg;甲基对硫磷检出率为88.8%,含量范围为ND~1.20μg/kg,平均为0.14μg/kg;马拉硫磷检出率为100%,含量范围为0.09~7.95μg/kg,平均为1.29μg/kg;对硫磷检出率为99.5%,含量范围为ND~3.46μg/kg,平均为0.5μg/kg。