烟草中阿维菌素的残留分析及消解动态

[目的]评价阿维菌素在烟草上使用的安全性，建立了超高效液相色谱-串联质谱(UPLC-MS/MS)检测烟草中阿维菌素的农药残留分析方法，并开展阿维菌素在烟草中的残留量与残留降解研究。[方法]消解试验按照阿维菌素30、45 g a.i./hm²一次施药于烟株，定期取样；最终残留试验按照阿维菌素30 (1.0倍推荐高剂量)、45 g a.i./hm²(1.5倍推荐高剂量)喷雾施药1次，施药后第28天取样。超高效液相色谱-串联质谱法对阿维菌素进行定量分析。[结果]田间试验消解动态结果表明：阿维菌素在烟叶中消解较快，消解半衰期为2.98～3.1 d，施药后28 d，烟叶中消解率达99.64%～99.80%。按照推荐剂量高剂量的1.0倍和1.5倍于烟草旺长期施药，距离末次施药的第28天采样，烟叶中阿维菌素的残留量远低于蔬菜水果残留限量标准。[结论]所建立方法的精密度、准确度、灵敏度均符合农药残留分析检测要求；阿维菌素在烟草中消解速率较快，属于易降解农药，推荐其在烟草上施用的使用剂量为30 g a.i./hm²，施药次数为1次，安全间...     

几种常用杀虫剂在洋葱上的残留降解动态

研究了毒死蜱、敌百虫和氯氰菊酯不同施药方法在洋葱上的残留降解动态。结果表明，毒死蜱喷雾在洋葱上的残留期较长，而采用药液灌根法施药，其残留期较短，残留量较少，即使在施药后第1d取样检测，残留量仍远远低于国家规定标准；敌百虫采用灌根法施药，在葱头中的残留量很低，施药后第1d取样检测，其残留量远远低于国家规定标准，这2种药剂可以作为防治地下害虫的良好杀虫剂。氯氰菊酯采用喷雾法施药，即使在施药后第1d，也检测不到农药残留，因此，是一种良好的喷雾用杀虫剂。     

5种制剂及其防治组合对黄瓜霜霉病的防效评价

[目的]筛选防治黄瓜霜霉病的有效药剂,降低施药量和施药次数。[方法]利用叶盘漂浮法测定5种药剂对黄瓜霜霉病菌毒力,并对不同制剂组合田间防效评价。[结果]双炔酰菌胺对黄瓜霜霉病菌抑制效果最好,EC50值为0.482 5 mg/L;在春秋2季黄瓜田间防治中,250 g/L双炔酰菌胺悬浮剂与60 g/L甲壳胺水剂交替施药组合效果显著,药后14 d的防治效果分别为72.47%和73.27%。[结论]250 g/L双炔酰菌胺悬浮剂与60 g/L甲壳胺水剂交替施药组合与常规施药相比,施药量降低20%~30%,施药次数减少2次,且对黄瓜安全。     

50%啶虫脒水分散粒剂在柑橘和土壤中残留量及消解动态

2009-2010年在四川、湖南及广西三省进行了50%啶虫咪水分散粒剂在柑橘和土壤中的残留试验。研究提供了不同施药剂量下啶虫咪在样本中的最终残留量和残留消解动态方程等结果。有效成分用量12.5～20 mg/kg,最多3次施药,施药间隔7d,采收间隔期为21d情况下,收获的柑橘全果残留量均低于0.5 mg/kg。     

二甲戊灵在烟草和土壤中的残留消解动态和残留量

[目的]为评价二甲戊灵在烟叶中使用的安全性,开展二甲戊灵在烟叶和土壤中的残留量与残留降解研究。[方法]进行2年2地田间试验。消解动态试验按二甲戊灵2 617 mg a.i./L杯淋1次,每株药液用量20 mL,定期取样;最终残留试验按二甲戊灵2617 mg a.i./L(1.5倍推荐高剂量)和1750 mg a.i./L(推荐高剂量)杯淋1次,施药后7、14、21 d取样。高效液相色谱法(带紫外检测器)对二甲戊灵进行定量分析。[结果]田间消解动态结果表明:二甲戊灵在烟叶和土壤中消解较快,半衰期分别为2.56～5.97、7.53～10.34 d,施药后35 d,烟叶和土壤中的消解率均达90%以上。按二甲戊灵2617、1750 mg a.i./L于烟草现蕾期杯淋施药1次,距末次施药后间隔21 d采样,烟叶中二甲戊灵的残留量低于0.02～0.12 mg/kg,土壤中的残留量低于0.005～0.037 mg/kg。     

气相色谱法测定黄瓜中百菌清含量的不确定度评定

本文介绍了气相色谱法测定黄瓜中百菌清含量的不确定度评定方法,分析了测量过程中不确定度的来源,对该方法所得分析结果的已识别来源的不确定度影响进行评价.黄瓜中百菌清残留的评定结果为(0.0319±0.0016)mg·kg-1;k=2 P=95%.     

气相色谱-负化学源-质谱联用检测烟草中氟氯氰菊酯的残留及消解动态

[目的]为评价氟氯氰菊酯在烟草上使用的安全性,建立氟氯氰菊酯在烟草中的残留分析方法,并开展氟氯氰菊酯在烟草和土壤中的残留降解研究。[方法]进行2地田间试验,样品经乙腈提取、净化后,质谱检测器检测。[结果]添加质量分数为0.05~5.0 mg/kg时,氟氯氰菊酯在鲜烟叶、干烟叶和土壤中平均添加回收率分别为88.4%~90.9%、89.8%~99.3%和83.6%~99.1%,相对标准偏差分别为5.5%~8.6%、4.7%~6.2%和8.4%~10.5%。氟氯氰菊酯在烟叶和土壤中半衰期分别为6.1~7.3、9.8~12.9 d。按34.2~51.3 g a.i./hm~2用量,喷雾施药1~2次,施药间隔7 d,距末次施药后间隔21 d采样,烟叶中氟氯氰菊酯的残留量为低于0.05~1.48 mg/kg。[结论]该方法快速简便,准确可靠。施药间隔21 d烟叶中氟氯氰菊酯残留低于国际烟草合作研究中心指导性残留限量标准规定的MRL值(2.0 mg/kg)。     

螺螨酯和联苯肼酯在柑橘中的残留降解及其膳食风险评估

为评价螺螨酯和联苯肼酯在柑橘上的环境安全性,采用田间试验方法,研究了自然条件下螺螨酯和联苯肼酯在柑橘上的消解动态和残留情况,探索施药最适安全间隔期。结果表明,40%螺螨酯·联苯肼酯悬浮剂稀释1667倍液施药1次,螺螨酯与联苯肼酯在柑橘全果中的半衰期分别为4.70 d、4.86 d;柑橘全果中的两种农药的残留量均受施药浓度和施药次数的影响,残留风险与田间用药剂量及用药次数呈正比例关系。参考国内外农药残留限量标准,建议在正常栽培条件下,按常规方法及作用剂量施药2次,柑橘的安全采收间隔期为30 d;当施药浓度或施药次数增加时,安全间隔期应适当延长。     

聚氨酯泡沫塑料中磷系阻燃剂的不确定度研究评定

通过用气相色谱-质谱联用法对软质阻燃聚氨酯泡沫塑料中的有机磷系阻燃剂化合物含量的不确定度进行评定,分析了测量过程中引入的不确定度来源,求出各不确定度分量,最后合成标准不确定度并计算相对扩展不确定度。结果表明,各化合物最大的不确定度分量是方法回收率,约占20%~30%,方法相对扩展不确定度为0.043~0.070。     

GC-MS/MS法测定茶叶中邻苯基苯酚残留量的不确定度评定

采用气相色谱-串联质谱法(GC-MS/MS)分析茶叶中邻苯基苯酚残留的不确定度。通过建立数学模型,分析不确定的来源,计算各个不确定度分量,将不确定度合成,得到该分析方法的测量不确定度评定方法。结果表明,由气相色谱-质谱仪引起的测量不确定所占权重最大,其次是内标溶液所引入的不确定度。样品称量引入的测量不确定度所占权重最小。通过分析发现,当邻苯基苯酚残留量为0.26 mg/kg时,该分析方法的测量扩展不确定度为0.02 mg/kg(k=2)。     

化学发光法测定原油及渣油中的氮含量

利用ANTEK7000化学发光分析仪，采用直接进样的方式测定原油、常压渣油和减压渣油中的氮含量。阐述方法原理，考察方法的重复性在允许重复性误差范围内；标准样品的回收率在95％-105％；与ASTMD5762．95的稀释法比较，结果一致性较好，两种结果的差值小于84个单位。计算分析过程中由于分析重复性、称量等因素所带来的不确定度分量，考察不确定度分量对合成标准不确定度的贡献，确定合成标准不确定度为3．86mg／kg。合成标准不确定度较小，样品单次分析时间为3-5min。测定范围从0．5mg／kg到质量分数17％。     

A study of the variability associated with sampling peanuts for aflatoxin

One lot of peanuts known to contain aflatoxin was extensively sampled to study the sources of variability. A nested design was used where sections (50 bag units), subsamples and analytical variation were the variables studied. Sample size was the most critical factor in characterizing this lot. Variability from section to section was not significant indicating random distribution of the contaminant. Three 20 lb samples were taken on a number of lots from the 1968 crop, each of which was subdivided into two equivalent subsamples. The aflatoxin was determined on each of these subsamples. The results indicated that all the significant variation came from the subsamples, further enforcing the thesis that sample size is the critical factor in variability, and not lot inhomogeneity. Analysis of 550 lots from the 1967 crop where triples and analysis were available indicates that the magnitude of the variability is a little greater than was found on the experimental lot. Using the pooled standard deviation of the 1967 crop data, operating characteristic curves were plotted to demonstrate the improvement that can be expected by increasing the sample size.     

Measurements of High Oleic Purity in Peanut Lots Using Rapid,Single Kernel Near-Infrared Reflectance Spectroscopy

High oleic peanuts have improved shelf life vs. conventional peanuts. Purity (percentage of high oleic peanuts within a lot) is critical to ingredient performance and final lot value. Contamination can result from unintentional mix-ups at the breeder/seed level, improper production handling, or due to physiologically immature high oleic kernels. Therefore, industry groups have established unofficial sampling plans to monitor purity. Assuming equivalent measurement performance and simple random sampling, increasing the sample size decreases variance among replicated sample test results and increases the precision of estimated lot purity. A novel instrument (QSorter Explorer by QualySense AG) using near-infrared reflectance spectroscopy was evaluated for high speed (20 kernels per second) high oleic purity measurements. The study objectives were to assess instrument performance in: (1) measuring oleic acid (%) in runner peanuts and (2) estimating the true high oleic purity of artificially mixed peanut lots. Three grades (Jumbo, Medium, and No 1) of US Runner mini-lots each at seven different contamination levels (0, 5, 10, 20, 30, 50, and 100%) were prepared. Oleic acid (%) of individual kernels was measured by scanning replicated samples of 10, 50, 100, and 500 kernels using the QSorter Explorer. The variance associated with each sample size and lot contamination level on returned purity values is discussed in the context of binomial sampling. Overall, the demonstrated measurement performance and capacity of the QSorter Explorer to process much larger sample sizes suggest this instrument can better identify true high oleic peanut lot purity vs. other currently available technologies.     

含硅熔渣对磷的吸附与固定的研究

为选择合适的含硅熔渣用于复合肥，本文对含硅溶渣样品进行了对磷的吸附与解吸和对磷的固定的测定，实验结果表明，2号，11号，21号三个渣样对磷的吸附量与固定率均比其他四个供试渣样少得多，且此三个渣样解吸率达到了30％－40％，根据本试验结果，可以初步选定2、11、21号渣样用于制复合肥。     

Uncertainty quantification via bayesian inference using sequential monte carlo methods for CO2 adsorption process

This work presents the uncertainty quantification, which includes parametric inference along with uncertainty propagation, for CO₂ adsorption in a hollow fiber sorbent, a complex dynamic chemical process. Parametric inference via Bayesian approach is performed using Sequential Monte Carlo, a completely parallel algorithm, and the predictions are obtained by propagating the posterior distribution through the model. The presence of residual variability in the observed data and model inadequacy often present a significant challenge in performing the parametric inference. In this work, residual variability in the observed data is handled by three different approaches: (a) by performing inference with isolated data sets, (b) by increasing the uncertainty in model parameters, and finally, (c) by using a model discrepancy term to account for the uncertainty. The pros and cons of each of the three approaches are illustrated along with the predicted distributions of CO₂ breakthrough capacity for a scaled‐up process. © 2016 American Institute of Chemical Engineers AIChE J, 62: 3352–3368, 2016     

微量法测定石油产品中残炭含量的不确定度评价

按照测量不确定度评定的通用规则,建立了数学模型,对微量法测定石油产品中残炭含量的测量不确定度进行了评定,分析了方法中的不确定度分量及其来源,计算了各分量的不确定度,最后计算出了检测结果的合成标准不确定度和扩展不确定度。检测结果和不确定度评定结果为（0．35±0．02）％,k=2。残炭质量称量引起的测量不确定度分量为最大。     

气相色谱法测定水产品中硝基苯残留量

本文建立了一种测定水产品中硝基苯残留量的气相色谱-质谱法。样品用乙腈提取,经液液分配后,用中性Al2O3固相萃取柱净化,利用气相色谱-质谱仪测定,外标法定量。硝基苯的浓度在0.005～1.000μg·mL-1范围内时,其相关系数和回归方程分别为r=0.99994和y=8555.93x-30.11。样品平均加标回收率在71.2%～93.6%之间,相对标准偏差为3.34%～4.18%。方法的最低检出限0.002mg·kg-1。     

DFP新型钒镍钝化剂在RFCCU的工业应用

在研究重金属镍、钒对烃类裂化催化剂中毒机理的基础上，通过具有一剂多能和协同作用元素间的复配和优化，并考虑工业应用的可行性和成本，研制了无毒、高效和稳定性好的DFP抗钒、抗镍双功能水溶性钝化剂，在乌鲁木齐石化公司1.2 Mt/a的重油催化裂化装置(RFCCU)进行了工业应用试验。结果表明，当原料油中掺质量分数为39％～42％的减压渣油，平衡剂上钒质量分数高达7.5×10^－9～9×10^－9，镍质量分数为5×10^－9～6×10^－9条件下，使用DFP钝化剂与国产钝化剂MP相比，轻质油收率提高0.45%,焦炭产率下降16％～20%,氢气产率下降25％～30%，平衡剂活性指数提高4～5个单位，使用方便，有显著的经济效益和社会效益。     

火焰原子吸收光谱法测定大米中锌含量的不确定度评估

对火焰原子吸收光谱法测定大米中锌含量的不确定度评估。由评估的结果可以看出:消解过程的不确定度分量是最大的,其次是标准工作曲线的拟合和测试样品重复测定引入的不确定度分量,仪器的稳定性也有—定的影响。在实际的分析过程中,可以改进样品的消解方法和提高检测分析人员的技术水平,从而可提高检测数据的准确性。当测试样品中锌含量为6....     

不同环境条件下白腐菌漆酶生物修复土壤DDT污染的动力学(英文)

Biodegradation of 2,2-bis(p-chlorophenyl)-1,1,1-trichloroethane(DDT)in soil by laccase extract from white rot fungi under different experimental conditions was investigated.DDTs,which stands for the sum of p,p′-DDE,o,p′-DDT,p,p′-DDD and p,p′-DDT in soil was degraded efficiently,and the residue decreased rapidly during the first 15 days and then slowly during the period of 16-25 days.The biodegradation of DDTs in soil fitted the pseudo-first-order kinetics.For 5,10,15 and 25 days of incubation with laccase,the residue of DDTs in soil under different atmospheres was decreased by 20%-33%,34%-52%,41%-61%and 41%-69%respectively,under different flooding conditions that was decreased by 12%-17%,17%-30%,30%-45%and 35%-52%respectively, and for different soils that was decreased by 25%-34%,39%-53%,44%-58%and 47%-62%respectively.The half-life of DDTs in soil ranged from 15.07 to 32.95 days under O2,air or N2 atmospheres,23.07 to 40.71 days under different flooding conditions,and 18.78 to 28.88 days for different soils.Laccase is an efficient and safe agent for bioremediation of DDT-contaminated soil.