纳米CuI催化偶联反应合成二苯醚类农药中间体     

潘攀  蔡振亚  叶加久  杨春燕  徐小岚 《现代农业科技》2010,(9):25-26

二苯醚是一种重要的农药中间体,通过W/O微乳法,制备出形貌均一的球状纳米CuI,并应用于催化C-O交叉偶联反应中,在温和的反应条件下,合成了具有优良产率的二苯醚类化合物,该方法可在今后的农药合成中应用。  相似文献   

同时分析粮食中敌敌畏等六种有机磷农药气相色谱条件的选择   总被引：2，自引：1，他引：1  

程兴杰  李万军  李雅莲  陈兆庆 《粮食储藏》2010,39(1):49-52

对气相色谱法检测粮食中敌敌畏、敌百虫、马拉硫磷、辛硫磷、杀螟硫磷、甲基嘧啶磷等6种有机磷农药残留量的色谱条件进行优化选择,比较了不同毛细管柱的分离效果,选择了气体的最佳流量和程序升温的最佳起始温度,使保留时间相差很小的组分得到了较好的分离,并提出了解决柱头污染的有效方法。  相似文献   

农药市场经营现状及存在问题与对策     

周新建  齐琨  翟玉壮 《农药科学与管理》2013,34(9):1-4

本文通过对石家庄市农药市场经营现状及存在问题的分析,探讨了新形势下农药经营者的出路及对策,并结合现代农业发展新趋势,探索监管新模式。  相似文献   

气相色谱法测定水果中咪鲜胺残留量的方法研究     

郑雪虹  吕岱竹  谢德芳  冯信平  林靖凌 《热带作物学报》2012,32(8):43-48

采用丙酮震荡提取样品，在水解衍生的步骤中创造性地使用试管加入吡啶盐酸盐，于220℃的烘箱里水解1.5 h，经过处理后使用气相色谱ECD进行测定。结果表明：该方法的线性范围为0.005～0.500 ng，相关系数为0.999 9；对香蕉、绿橙、花牛苹果、青苹果、猕猴桃、砀山梨6种空白基质分别进行了0.01、0.10、1.00 mg/kg 3个水平加标，其回收率为81.0%～106.4%，相对标准偏差(RSD，n＝5)为0.3%～5.7%；该方法的最低检出限为0.01 mg/kg，并且烘箱水解的新方法操作简便  相似文献   

农药复合配制使用效果     

赵奎  王成林 《北京农业》2012,(15):257

介绍农药复合配制的方法,并进行药效试验,为推广使用提供依据.  相似文献   

Organoclays for controlled release of the herbicide fenuron     

Hermosin MC  Calderón MJ  Aguer JP  Cornejo J 《Pest management science》2001,57(9):803-809

Organoclays were assayed as matrices in which to associate herbicides, with the aim of decreasing product losses that could give rise to water contamination from agricultural activities. Fenuron was selected as model of a very mobile and highly water-soluble herbicide. Two different organoclays of high (A-HDT) and low (H-C18) reversible fenuron sorption were selected. Herbicide-organoclay complexes were prepared from the two organoclays and with two different fenuron contents (20 and 40 g AI kg-1) and two different mixing times, so as to form a series of weak and strong complexes. The release of fenuron from those complexes into water and water/soil suspensions gave values of T50 (time to release 50% of the fenuron content) ranging from 0.3 min to 2400 h. The total fenuron released in these closed systems ranged from 48 to 80% of the fenuron in the complex. The organoclay type (high or low sorptivity) had the greatest influence on fenuron release, followed by the strong or weak complex, suggesting that herbicide-organoclay interactions are the main factors controlling release. Soil column leaching experiments showed fenuron-organoclay complexes to be effective in reducing the peak herbicide concentration in the leachate to a half (6 microns) or a quarter (3 microns) of that obtained from the free technical compound (12 microns). Herbicide lost through leaching was reduced from 78% for the free technical fenuron to 50-30%, depending on the organoclay used as carrier and the strength of the complex. Bioassay with ryegrass showed that the weak fenuron/H-C18 complex (40 g AI kg-1) gave the same herbicidal activity as technical fenuron. The potential suitability of low-sorptive organoclays for conferring slow-release properties on the fenuron complex has been demonstrated.  相似文献   

The effect of the herbicide diuron on soil microbial activity     

Prado AG  Airoldi C 《Pest management science》2001,57(7):640-644

The inhibitory effect of the herbicide diuron [3-(3,4-dichlorophenyl)-1,1-dimethylurea] on microbial activity in red Latosol soil was followed using microcalorimetry. The activity of the micro-organisms in 1.50 g of soil sample was stimulated by addition of 6.0 mg of glucose and 6.0 mg of ammonium sulfate under 35% controlled humidity at 298.15 (+/- 0.02) K. This activity was determined by power-time curves that were recorded for increasing amounts of diuron, varying from zero to 333.33 micrograms g-1 soil. An increase in the amount of diuron in soil caused a decrease of the original thermal effect, to reach a null value above 333.33 micrograms g-1 of herbicide. The power-time curve showed that the lag-phase period and peak time increased with added herbicide. The decrease of the thermal effect evolved by micro-organisms and the increase of the lag-phase period are associated with the death of microbial populations caused by diuron, which strongly affects soil microbial communities.  相似文献   

Pyrethroid insecticide residues on vegetable crops     

Ripley BD  Ritcey GM  Harris CR  Denommé MA  Brown PD 《Pest management science》2001,57(8):683-687

Pyrethroid insecticides were applied on various vegetable crops as foliar treatments to determine dissipation rates. On Chinese broccoli (Guy Lon), Chinese mustard (Pak Choi) and Chinese cabbage (Kasumi, napa), fenvalerate was persistent with residues of 0.10, 0.14 and 0.11 mg kg-1, respectively, by day 21. Cypermethrin residues on head lettuce were below 0.1 mg kg-1 by day 10 but on the leafier romaine and endive varieties it was more persistent and required 14-19 days to dissipate below this concentration. After three applications, residues of cypermethrin in harvested carrots and of permethrin in eggplant were not detected on the day of application. On asparagus, deltamethrin and cypermethrin residues declined to less than 0.1 mg kg-1 by days 1 and 2, respectively; permethrin was more persistent, requiring more than 2 days to decline to less than 0.1 mg kg-1. Deltamethrin on dry (cooking) and Spanish onions was not detected on the day of application. On tomatoes, the concentration of permethrin was 0.093 mg kg-1 on the day of application and declined to about 0.05 mg kg-1 after 2-4 days. In general, permethrin, cypermethrin and deltamethrin residues declined to acceptable concentrations within an acceptable pre-harvest interval. Fenvalerate may be too persistent on these speciality crops unless a maximum residue limit > 0.1 mg kg-1 is permitted.  相似文献   

灰飞虱不同虫量与水稻条纹叶枯病发病的相关性研究   总被引：5，自引：1，他引：5  

徐晓兰  张银贵  杨爱国 《中国植保导刊》2005,25(3):5-6

通过田间水稻1代灰飞虱成虫高峰期罩笼接虫传毒试验,结果表明,带毒灰飞虱属持久性传毒型介体昆虫,并随虫量的增加,水稻条纹叶枯病发病呈上升趋势,以400～600头/m2时发病较为明显。浸种试验显示,用25%咪鲜胺EC(使百克) 10%二硫氰甲烷EC(浸种灵) 12.5%吡虫啉SL浸稻种有控虫防病效果。  相似文献   

聚乙烯醇共混改性膜作为农药种衣剂成膜剂的性能研究   总被引：5，自引：0，他引：5       下载免费PDF全文

潘立刚  周一万  叶海洋  郝双红  张兴 《农药学学报》2005,7(2):160-164

以水溶性聚合物聚乙烯醇(PVA)和水不溶性聚合物乙酸乙烯-乙烯共聚物(VAE)乳液为原料,采用溶液共混法制备了PVA-VAE共混膜,为农药成膜剂的制备开辟了新途径。红外光谱、透射电镜、激光粒度仪测试结果显示,PVA溶液中的胶束被打开,体系的比表面积急剧增大,两相间的界面消失,说明共混体系分子间具有良好的相容性;透水性与耐水性测定结果表明,PVA-VAE的质量比为80∶ 20、70∶ 30、60∶ 40时其共混膜的性能适用于农药种衣剂的成膜剂;种子发芽试验显示,与单独使用PVA膜相比,引入适当比例VAE后的共混膜用于种子包衣,其耐水性显著提高,渗水率适宜,对种子发芽无明显影响。  相似文献