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991.
Abstract

A series of [(substituted phenoxyacetoxy)(substituted phenyl)methyl](methyl)phos- phinates containing fluorine were designed and synthesized. All the synthesized compounds were identified by elemental analysis, IR, 1H NMR, mass spectrometry. O-methyl [(2-fluorophenoxyacetoxy)(2,4-dichlorophenyl)methyl](methyl)phosphinate was further analyzed by X-ray single-crystal diffraction. Their herbicidal activity against a set of weed species was examined. Some of the compounds showed potential herbicidal activity, which provided some indications for further studies on structure modification.

Supplemental materials are available for this article. Go to the publisher's online edition of Phosphorus, Sulfur, and Silicon and the Related Elements to view the free supplemental file.  相似文献   
992.
Ionic liquid–modified silica has been prepared by a “one-pot” reaction of activated silica, 3-chloropropyltriethoxysilane, and alkylimidazole or pyridine. It was found that the catalytic activity and β-adduct selectivity of the supported catalyst Rh(PPh3)3Cl/ionic-liquid–modified-SiO2 for the hydrosilylation reaction of alkenes with triethoxysilane was significantly improved. Furthermore, the catalyst system could be recovered easily.  相似文献   
993.
The interactions between β‐cyclodextrin (β‐CD) and the mixtures of cationic‐anionic surfactants in the aqueous solution were investigated by surface tension, rheology, and dynamic light scattering measurements. It was shown that the key‐lock interactions between β‐CD and mixed cationic‐anionic surfactants were stronger than the electrostatic/hydrophobic interactions between cationic and anionic surfactants. The inclusion of β‐CD to surfactants could destroy the ion‐pair and aggregates of cationic‐anionic surfactants, and even inhibited the precipitation of the mixed cationic‐anionic surfactants. Furthermore, the inclusion of β‐CD to surfactants could also destroy the hydrogen bond between β‐CD molecules, inducing the disassociation of the aggregation formed by β‐CD themselves.  相似文献   
994.

A series of polyglycerol diisostearate ethoxylates with two hydrophobic chains were prepared by the reaction of polyglycerol diisostearate with ethylene oxide. Surface properties including water solubility, cloud temperature, critical micelle concentration, emulsification, and the solubilizing capacity of polyglycerol diisostearate ethoxylates for simvastatin were investigated in comparison with those of Tween‐80. The critical micelle concentrations of all polyglycerol diisostearate ethoxylates are less than 0.01 mmol l?1, which is one order of magnitude lower than that of Tween‐80. Polyglycerol diisostearate ethoxylates show better emulsification than Tween‐80. For enhancing the solubility of simvastatin in micelles, polyglycerol diisostearate ethoxylates also are superior to Tween‐80.  相似文献   
995.
Xanthan enhanced foam (XGF) is a newly developed chemical agent for enhanced oil recovery in high-temperature and high-salinity reservoirs. In this paper, laboratory experiments were performed to characterize the morphology and foam properties of XGF, to study its performance under different temperature and different salinity conditions, respectively. Based on simulate reservoir formation conditions of Xidaliya field, a series of research on XGF were conducted. The experimental results showed that the scanning electron microscopy of XGF reflected a more viscoelastic and stable nature of the foam system. High temperature had a great adverse impact upon the stability of XGF, and the increase of salinity in the solution helped to improve the stability of foam. The foam stability increased remarkably when XG4 is added, and an increase in ambient pressure made enhancement of foam stability became more noticeable. In the presence of crude oil, Xanthan could enhance the stability of emulsions and was more favorable to stabilize foam. XG4 enhanced foam had dramatic properties for mobility controlling and oil displacement in the porous media.  相似文献   
996.
建立了新型的解吸附电晕束离子源耦合离子阱质谱法(DCBI-MS),在无需复杂的样品前处理及色谱分离的条件下,可快速检测降血压中成药及保健食品中非法添加的7种β-受体阻滞剂阿替洛尔、比索洛尔、美托洛尔、普萘洛尔、盐酸塞利洛尔、盐酸贝凡洛尔和卡维地洛.采用一级质谱快速筛选和二级质谱确证的方法对目标化合物进行了定性和半定量测定.各目标物的检出限均低于0.1 mg/L,在0.5~100 mg/L浓度范围内线性关系良好.实验获得的7种β-受体阻滞剂的裂解规律为芳氧丙醇胺类化合物的质谱检测提供了参考依据.通过与高效液相色谱-电喷雾离子化质谱法(HPLC-ESI/MS)对比表明,DCBI-MS方法的检测结果可靠.对9种市售样品进行检测,有1批次中成药检出含有未标示的卡维地洛.结果表明,DCBI-MS法测定单个样品的时间不超过1 min,分析速度快,可以在大批量复杂基质样品中β-受体阻滞剂的筛查和药品品质的在线监测中发挥重要作用.  相似文献   
997.
用光刻法在普通定量滤纸上制作出了疏水图案,得到了滤纸微孔板。将表面修饰后的SiO2微球负载在滤纸表面,以提高滤纸纤维吸附蛋白质的能力,基于此建立了以间接酶联免疫吸附法测定羊抗兔免疫球蛋白的方法。以酶标兔抗羊IgG为例,负载SiO2微球后,滤纸微孔板吸附该蛋白质的量提高了20%~700%;将SiO2负载法应用于羊抗兔IgG的检测时,可使信号增强20%~150%。在本实验条件下,测定羊抗兔IgG的线性范围为3×10-12~3×10-8mmol/孔。本方法使生物免疫试剂消耗量减少至3~5μL/孔、检测时间降至20 min/板、滤纸微孔板制作成本可低至约每板1.1美元,为研制准确、快速和低成本的疾病检测设备提供了新的思路和可能性。  相似文献   
998.
以柠檬酸为螯合剂,十六烷基三甲基溴化胺为表面活性剂,通过ZrOCl2·8H2O 与对苯二甲酸 (H2BDC) 反应制备了同时具有微孔和介孔结构的Zr基金属有机骨架材料(Zr-MOF),并在超临界CO2-甲醇流体中将 Ru 负载于 Zr-MOF 上, 制备了 Ru@Zr-MOF催化剂,采用傅里叶变换红外光谱、X射线粉末衍射、透射电子显微镜、热重分析、N2吸附-脱附、X射线光电子能谱和电感耦合等离子体发射光谱对催化剂进行了表征,研究了该催化剂在苯及其同系物加氢反应中的催化性能. 结果表明,Ru纳米金属颗粒均匀地分散在Zr-MOF载体上,平均粒径约为2.3nm,在苯及其同系物的加氢反应中表现出很高的催化活性和稳定性.  相似文献   
999.
采用密度泛函理论研究了ZrO2负载的Ru基、Rh基以及Re改性的Rh基、Ir基催化剂上甘油氢解生成1,2-丙二醇和1,3-丙二醇的热力学过程, 重点考察了ReOx调变催化剂活性和选择性的作用机制. 结果表明, Ru/ZrO2和Rh/ZrO2催化剂上甘油分解经由脱水-加氢反应途径, 1,2-丙二醇的生成是热力学有利过程, 其中Ru基催化剂活性更高. 在Re修饰的Rh基和Ir基催化剂上, 反应遵循直接氢解机理, 其中金属表面解离的氢原子进攻ReOx团簇上与醇盐紧邻的C-O键是催化甘油转化为丙二醇最核心的步骤. ReOx-Rh/ZrO2催化剂上1,2-丙二醇为主要产物, 并伴随1,3-丙二醇的生成, ReOx的修饰则显著提高了Ir/ZrO2催化剂上1,3-丙二醇选择性. 与单金属催化剂上发生的间接氢解机理相比, 修饰催化剂上1,3-丙二醇选择性的提高可主要归因于Rh(Ir)-Re协同催化的直接氢解反应过程, 其中羟基化铼官能团有利于末端醇盐中间体的生成. ReOx-Ir/ZrO2催化剂上较大的Ir-Re团簇使得末端金属醇盐的立体优选性比次级醇盐更为突出, 从而具有最高的1,3-丙二醇选择性.  相似文献   
1000.
A novel and easy synthetic route to diethyl (5-substituted phenyl-1,3,4-thiadiazol-2-ylamino) (substituted phenyl) methylphosphonates has been achieved by the reaction of substituted benzylidene-5-(substituted phenyl)-1,3,4-thiadiazol-2-amines and diethyl phosphite under microwave irradiation. These 1,3,4-thiadiazole aminophosphonates were identified by infrared, 1H NMR, and elemental analyses. The target compounds were obtained in better yields (71–89%) and shorter time (10 min) than with conventional heating.

Additional information

ACKNOWLEDGMENTS

This work was supported by the Jiangsu High-Tech Research Project (Agriculture) (BG2007329) from the Science and Technology Department of Jiangsu Province and the Youth Teacher Academic Foundation of Nanjing University of Technology. We thank the Science and Technology Department of Jiangsu Province for financial support.  相似文献   
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