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1.
于2005年11月随机选取通辽市六个旗、县、区的水稻种植区,对市售当地产稻米样品抽样,采用毛细管胶束电动色谱法检测稻米中水胺硫磷和灭多威农药.结果表明,除科左后旗外,其余地区的稻米中均检出了农药,水胺硫磷残留量范围在0.0928~0.1465mg/kg,灭多威残留量范围在0.1102~0.2757 mg/kg,水胺硫磷超标率为33.3%,灭多威超标率为66.7%.说明通辽市部分地区稻米中水胺硫磷和灭多威农药含量超标,应加强农药使用监督管理.  相似文献   

2.
辛硫磷生产新工艺一、概述:辛硫磷为有机磷杀虫剂,具有杀虫谱广、击倒力强、作用迅速、低毒等特点,对棉花、粮食、果树、蔬菜、贮粮、卫生、畜牧及地下等方面的害虫,均有良好防效,该产品以其高效、低毒广谱的优异性能,成为当今有机磷类农药的主导产品,市场经久不衰,尤其是随着高毒农药的更新换代,出现了很多以辛硫磷为主的农药复配新品种,近几年,出现了供不应求的局面。  相似文献   

3.
有机膨润土辛硫磷缓释剂的制备和释放研究   总被引:1,自引:0,他引:1  
使用缓释剂是减少农药对环境污染的有效策略。为开发成本低廉且具有释放速度调节能力的农药缓释剂,以十六烷基三甲基氯化铵(HTMAC)为改性剂制备的有机膨润土作为辛硫磷的载体,制备辛硫磷缓释颗粒剂,分析在水中辛硫磷颗粒剂的释放行为。结果显示,HTMAC改性有机膨润土对辛硫磷具有良好的吸附性能,其吸附量最高可达0.966 g/g膨润土。有机膨润土极大延缓了辛硫磷的释放速率,控制季铵盐的用量可以在一定程度上调节辛硫磷的释放速率,50%辛硫磷活性成分从改性剂用量为50%、100%和150%可交换阳离子容量的有机膨润土颗粒剂的释放时间T50分别为普通颗粒剂的3.4倍、10.4倍和10.1倍。  相似文献   

4.
灭多威对美国棉铃虫细胞的抑制作用研究   总被引:1,自引:0,他引:1  
运用 LKB2 2 77生物活性检测仪在 2 8℃下测定了昆虫细胞 (美国棉铃虫 Hz)的离体基础代谢热值 (其值为 2 3.6p W/ cell) ,研究了不同浓度的灭多威农药对昆虫细胞代谢产热功率的影响 ,并对其影响进行了讨论 .同时测得了农药 (灭多威 )对美国棉铃虫 Hz的半抑制量浓度 EC5 0 为1 96μg·m L- 1 ,并讨论了抑制率与农药浓度之间的关系  相似文献   

5.
灭多威在黄河水体沉积物中的吸附特性研究   总被引:5,自引:0,他引:5  
以黄河水体沉积物为研究对象,探讨了氨基甲酸酯类农药灭多威在沉积物上的吸附特性。同时还研究了pH值和离子强度等因素对吸附的影响,结果表明,灭多威在沉积物中的吸附等温线呈中凹型,属多分子层吸附,可用de Boer-Zwikker公式所表示的极化模型较好地描述其吸附行为;pH值或离子强度升高,均可使灭多威在沉积物上的吸附量减小。  相似文献   

6.
取适量的O,O-二乙基硫代磷酰氯加蒸馏水,置于特制的聚四氟乙烯容器中,进行微波辐射,得到理论量的磷酸,其余产物均得到证实,有机磷农药:辛硫磷、米乐尔在同样条件下也能彻底水解。  相似文献   

7.
辛硫磷农药对土壤螨类影响的研究   总被引:7,自引:3,他引:7  
通过辛硫磷农药对未污染土壤长达半年的染毒模拟实验,发现螨类是土壤动物的优势类群,对农药较敏感,随着农药浓度的增加,螨类数量逐渐减少.随着季节变化,其数量有波动.甲螨的变化规律与蜱螨类似.巴西甲螨、三皱甲螨可作为辛硫磷农药污染的指示生物,因为随着浓度的增加,巴西甲螨指数升高,而三皱甲螨指数则降低.这种变化趋势为农药污染的监测提供了重要的参考依据.  相似文献   

8.
浊点萃取用于有机磷农药残留的检测   总被引:3,自引:0,他引:3  
以建立农药残留快速检测技术为目的,利用非离子表面活性剂(C12E10)水溶液的浊点萃取特性,进行了水溶液中痕量的有机磷农药甲基对硫磷、辛硫磷富集分离的实验研究;考察了表面活性剂浓度、盐浓度、有机磷浓度、干扰物等因素对浊点萃取效果的影响。结果表明,C12E10浊点萃取技术对于甲基对硫磷、辛硫磷具有很好的富集分离效果,在35℃、C12E10浓度为5g.L-1、Na2SO4浓度为120g.L-1时,两种有机磷农药富集倍数最高分别可达95和97,萃取率也可达到90%以上。将浊点萃取技术与高效液相色谱分析法结合,甲基对硫磷和辛硫磷的检测限可达1μg.L-1。  相似文献   

9.
以建立农药残留快速检测技术为目的,利用非离子表面活性剂(C12E10)水溶液的浊点萃取特性,进行了水溶液中痕量的有机磷农药甲基对硫磷、辛硫磷富集分离的实验研究;考察了表面活性剂浓度、盐浓度、有机磷浓度、干扰物等因素对浊点萃取效果的影响。结果表明,C12E10浊点萃取技术对于甲基对硫磷、辛硫磷具有很好的富集分离效果,在35℃、采用C12E10浓度为5 g·L-1、Na2SO4浓度为120 g·L-1时,两种有机磷农药富集倍数最高分别可达95和97,萃取率也可达到90%以上。将浊点萃取技术与高效液相色谱分析法结合,甲基对硫磷和辛硫磷的检测限可达1μg·L-1。  相似文献   

10.
辛、甲混合制剂是由辛硫磷与甲拌磷两种农药复配而成的。采用薄层层极-溴化法同时对两种农药有效成分进行定量分析,具有简便、快速、准确度高等优点。  相似文献   

11.
Language markedness is a common phenomenon in languages, and is reflected from hearing, vision and sense, i.e. the variation in the three aspects such as phonology, morphology and semantics. This paper focuses on the interpretation of markedness in language use following the three perspectives, i.e. pragmatic interpretation, psychological interpretation and cognitive interpretation, with an aim to define the function of markedness.  相似文献   

12.
何延凌 《科技信息》2008,(4):258-258
Language is a means of verbal communication. People use language to communicate with each other. In the society, no two speakers are exactly alike in the way of speaking. Some differences are due to age, gender, statue and personality. Above all, gender is one of the obvious reasons. The writer of this paper tries to describe the features of women's language from these perspectives: pronunciation, intonation, diction, subjects, grammar and discourse. From the discussion of the features of women's language, more attention should be paid to language use in social context. What's more, the linguistic phenomena in a speaking community can be understood more thoroughly.  相似文献   

13.
王慧 《科技信息》2008,(10):240-240
Wuthering Heights, Emily Bronte's only novel, was published in December of 1847 under the pseudonym Ellis Bell. The book did not gain immediate success, but it is now thought one of the finest novels in the English language. Catherine is the key character of this masterpiece, because everybody and everything center on her though she had a short life. We can understand this masterpiece better if we know Catherine well.  相似文献   

14.
The Williston Basin is a significant petroleum province, containing oil production zones that include the Middle Cambrian to Lower Ordovician, Upper Ordovician, Middle Devonian, Upper Devonian and Mississippian and within the Jurassic and Cretaceous. The oils of the Williston Basin exhibit a wide range of geochemical characteristics defined as "oil families", although the geochemical signature of the Cambrian Deadwood Formation and Lower Ordovician Winnipeg reservoired oils does not match any "oil family". Despite their close stratigraphic proximity, it is evident that the oils of the Lower Palaeozoic within the Williston Basin are distinct. This suggests the presence of a new "oil family" within the Williston Basin. Diagnostic geochemical signatures occur in the gasoline range chromatograms, within saturate fraction gas chromatograms and biomarker fingerprints. However, some of the established criteria and cross-plots that are currently used to segregate oils into distinct genetic families within the basin do not always meet with success, particularly when applied to the Lower Palaeozoic oils of the Deadwood and Winnipeg Formation.  相似文献   

15.
理论推导与室内实验相结合,建立了低渗透非均质砂岩油藏启动压力梯度确定方法。首先借助油藏流场与电场相似的原理,推导了非均质砂岩油藏启动压力梯度计算公式。其次基于稳定流实验方法,建立了非均质砂岩油藏启动压力梯度测试方法。结果表明:低渗透非均质砂岩油藏的启动压力梯度确定遵循两个等效原则。平面非均质油藏的启动压力梯度等于各级渗透率段的启动压力梯度关于长度的加权平均;纵向非均质油藏的启动压力梯度等于各渗透率层的启动压力梯度关于渗透率与渗流面积乘积的加权平均。研究成果可用于有效指导低渗透非均质砂岩油藏的合理井距确定,促进该类油藏的高效开发。  相似文献   

16.
As an American modern novelist who were famous in the literary world, Hemingway was not a person who always followed the trend but a sharp observer. At the same time, he was a tragedy maestro, he paid great attention on existence, fate and end-result. The dramatis personae's tragedy of his works was an extreme limit by all means tragedy on the meaning of fearless challenge that failed. The beauty of tragedy was not produced on the destruction of life, but now this kind of value was in the impact activity. They performed for the reader about the tragedy on challenging for the limit and the death.  相似文献   

17.
Location based services is promising due to its novel working style and contents.A software platform is proposed to provide application programs of typical location based services and support new applications developing efficiently. The analysis shows that this scheme is easy implemented, low cost and adapt to all kinds of mobile nework system.  相似文献   

18.
正The periodicity of the elements and the non-reactivity of the inner-shell electrons are two related principles of chemistry,rooted in the atomic shell structure.Within compounds,Group I elements,for example,invariably assume the+1 oxidation state,and their chemical properties differ completely from those of the p-block elements.These general rules govern our understanding of chemical structures and reactions.Using first principles calcula-  相似文献   

19.
We have developed an adiabatic connection to formulate the ground-state exchange-correlation energy in terms of pairing matrix linear fluctuations.This formulation of the exchange-correlation energy opens a new channel for density functional approximations based on the many-body perturbation theory.We illustrate the potential of such approaches with an approximation based on the particle-particle Random Phase Approximation(pp-RPA).This re-  相似文献   

20.
正The electronic and nuclear(structural/vibrational)response of 1D-3D nanoscale systems to electric fields gives rise to a host of optical,mechanical,spectral,etc.properties that are of high theoretical and applied interest.Due to the computational difficulty of treating such large systems it is convenient to model them as infinite and periodic(at least,in first approximation).The fundamental theoretical/computational problem in doing so is that  相似文献   

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