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排序方式: 共有778条查询结果,搜索用时 328 毫秒
1.
Liming Fan Feng Wang Dongsheng Zhao Yuxin Peng Yuxin Deng Yinwei Luo Xiutang Zhang 《应用有机金属化学》2020,34(12):e5960
Guided by the self-penetrating features can improve the stability of metal organic frameworks (MOFs), an unprecedented 3D self-penetrated framework, {[Zn (tptc)0.5(bimb)]·H2O}n ( NUC-6 , here NUC corresponding to North University of China), with 3D (4,4)-c {86} net, was designed. Benefit from the high chemical stability and excellent luminescent property, NUC-6 can be act as an efficient multi-response chemo-sensor in detecting dichloronitroaniline pesticide and nitrofuran antibiotics in water with the detection limits are 116 ppb for DCN pesticide, 16 ppb for NFT antibiotic, and 12 ppb for NTZ antibiotic. Besides, the mechanisms of luminescence quenching were revealed from the viewpoint of internal filter effect (IFE) and photo-induced electron transfer (PET), implied by the optical spectroscopy and quantum chemical calculation. This work provides a promising strategy to design stable MOFs by improving the self-penetrating features and to expand their practical applications in the detection of organic pollutants in aqueous medium. 相似文献
2.
甲基对硫磷的快速测定及电化学性质 总被引:3,自引:2,他引:1
研究了杀虫剂甲基对硫磷的电化学性质。在pH10.38的Bdtton—Robinson缓冲溶液中,采用微分脉冲溶出伏安法在悬汞电极上得到一个还原峰,峰电位为-0.5V(vs.Ag/AgCl),本工作对实验条件进行了深入的研究,结合线性扫描伏安法等手段。研究了体系的电化学行为。实验表明,甲基对硫磷在汞电极上具有吸附性,电极反应具有不可逆性。该法用于水果及水样中甲基对硫磷残余量的测定,结果满意。 相似文献
3.
通过溶液共混及流涎成膜法制备了一系列不同C60乙醇胺含量的壳聚糖共混膜。以及含Cu(Ⅱ)的C60乙醇胺/壳聚糖共混膜。研究表明,C60乙醇胺/壳聚糖共混膜具有优异的可调紫外滤光性能,随着C60乙醇胺含量的增加,其紫外滤光波长从200nm红移至400nm左右。在该复合体系中引入Cu(Ⅱ)能有效改善膜的紫外光学性能,同时还初步探讨了这类复合材料的紫外滤光机制。 相似文献
4.
许多乙酰芳胺类化合物具有优异的生物活性,例如除草剂苯噻草胺,可抑制细胞生长和分裂,防除稻田中禾本科杂草[1];杀菌剂甲霜灵可防治作物霜霉病[2]。本文将具有多种生物活性的嘧啶基团引入到乙酰芳胺结构中[3],合成下列10个未见文献报道的标题化合物Ⅰ,通... 相似文献
5.
A study of the electrochemical reduction of the mesotrione pesticide on a hanging mercury drop electrode (HMDE) was performed
as a basis for the development of a sensitive analytical method for natural samples. The electrochemical characteristics of
herbicide mesotrione dissolved in a phosphate buffer (pH 7.0) have been determined by means of electrochemical techniques
such as cyclic voltammetry (CV) and differential pulse voltammetry (DPV) over a wide range of pH from 2.0 to 10.0. The experimental
parameters, such as electrolyte type and its pH, pulse amplitude, and scan rate were optimized. The method was applied to
the determination of the pesticide in a spiked soil samples. Using this method, a linear calibration curve for mesotrione
was obtained up to the 0.1 μM range in pH 7 phosphate buffer solution with a detection limit (S/N = 3) of 50 nM. The method
can be applied successfully to the determination of mesotrione in soils.
The text was submitted by the authors in English. 相似文献
6.
Ro Jin Pak Ayanendranath Basu 《Annals of the Institute of Statistical Mathematics》1998,50(3):503-521
This paper deals with the minimum disparity estimation in linear regression models. The estimators are defined as statistical quantities which minimize the blended weight Hellinger distance between a weighted kernel density estimator of errors and a smoothed model density of errors. It is shown that the estimators of the regression parameters are asymptotic normally distributed and efficient at the model if the weights of the density estimators are appropriately chosen. 相似文献
7.
毛细管气相色谱法测定5种中草药中有机氯农药的残留量 总被引:38,自引:0,他引:38
建立了怀牛夕等 5种中草药中六六六及滴滴涕异构体含量的气相色谱分析方法。样品以石油醚 +丙酮在索氏提取器中提取 ,提取液以浓硫酸净化。采用SE 30弹性石英毛细管柱分离样品 ,GC ECD检测六六六、滴滴涕农药的残留量。方法的线性范围为 5 .7× 10 - 7~ 2 .8× 10 - 4μg ;最小检测量为 1.3× 10 - 1 4~ 2 .5×10 - 1 2 g ;加样平均回收率为 88.8%~ 99.1% ;RSD为 0 .9%~ 5 .3%。 相似文献
8.
9.
Nicolas Le Calvez 《中国化学会会志》2002,49(4):585-592
The aim of this study was to develop an analytical method to determine the organochlorine concentrations in sediments. Combination of Microwave assisted Solvent Extraction (MASE) and capillary gas chromatography with specific detection (electron capture detector) was a viable approach for the determination of pesticides in solid matrixes. In this study, MASE development was focused on the selection of a suitable extraction solvent for all the target analytes. MASE procedure was validated by comparison with conventional methods such as Soxhlet and sonication extraction. The proposed method was then applied to determine the organochlorine insecticides concentrations in samples from Authie Bay (France). Environmental water samples were analysed and five target analytes were detected in concentrations from 0.03 to 0.56 ng/g of dry sediment. These investigations showed the accumulation and the persistency of these products in sediments in spite of the fact they were banned a few decades ago. 相似文献
10.
Sol-gel entrapment of monoclonal anti-atrazine antibodies 总被引:1,自引:0,他引:1
A. Turniansky D. Avnir A. Bronshtein N. Aharonson M. Altstein 《Journal of Sol-Gel Science and Technology》1996,7(1-2):135-143
We report the successful doping of a sol-gel matrix with an antibody, retaining its ability to bind free antigen from an aqueous solution. The particular system described is monoclonal anti-atrazine mouse antibody which was entrapped in SiO2 sol-gel matrices, prepared from tetramethoxysilane by several methods. Atrazine was selected as a model compound for this study, within the framework of the development of immunochemical-based methods for monitoring pesticide residues and other organo-synthetic environmental contaminants. Nanogram quantities of atrazine were applied on SiO2 sol-gel columns doped with this antibody, and the amount of eluted antigen was determined by Enzyme Linked ImmunoSorbent Assay (ELISA). Under appropriate sol-gel-forming conditions, high amounts of atrazine were bound to the sol-gels, ranging between 60% and 91% of the amount applied to the column. The combination of the properties of the sol-gel matrix (e.g., stability, inertness, high porosity, high surface area and optical clarity), together with the selectivity and sensitivity of the antibodies, enable extension of this feasibility study to development of a novel group of immunosensors which could be used for purification, concentration and monitoring of a variety of residues from different sources.Contribution from the Agricultural Research Organization (ARO), Bet Dagan, Israel. No., 1697-E, 1995 series. 相似文献