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991.
992.
The enhanced biological activities of three Zn (II) complexes based on different 1,2,4‐triazole fungicides 下载免费PDF全文
Guo‐yu Ren Jie Li Xu‐zhan Wei Jin‐hua Zhou Biao Yan Zhao‐qi Guo Ying‐hui Ren Xiao‐hong Sun Hai‐xia Ma 《应用有机金属化学》2018,32(9)
In order to screen effective fungicides, three Zn (II) complexes, [Zn L 1 4 (NO3)2]·2H2O·2EtOH ( 1 ), [Zn L 2 4 (NO3)2] ( 2 ), and [Zn L 3 4 (DMF)2](NO3)2 ( 3 ), ( L 1 = paclobutrazol, L 2 = diniconazole, and L 3 = hexaconazole), were synthesized and characterized by elemental analysis, FT‐IR spectroscopy, and single‐crystal XRD. The antifungal activities of these complexes were then evaluated against four selected fungi using the mycelial growth rate method. The resulting data indicate that all the complexes show the enhanced antifungal activities than the corresponding ligand and mixtures. And, the interactions between the metal salt and ligands in the three complexes seem to be synergistic. According to the study of the influence of the structures on the activity, complex 2 with C=C linkage and 2,4‐dichlorophenyl moieties enhances the bioactivity significantly, especially against Wheat gibberellic ( II ). Density functional theory (DFT) calculations were carried out to help explain the enhanced bioactivity of the Zn (II) complexes. Meanwhile, all complexes are excellent grow‐regulators, especially complex 3 . The resulting data show that the complexes based on triazole fungicides have the potential applications in agriculture. 相似文献
993.
The excitation energy transfer between a donor–acceptor pair with fixed distance apart through energy exchanging with environment is investigated. The total system is modeled as two two-level systems (TLSs) interacting with many harmonic oscillators. The pair behaves coherently or incoherently, depending on whether the dipolar coupling is stronger or weaker than the TLS–environment coupling. The environmental linear dispersion relation gives an analytical solution to the pair?s probability involving all the retardation times. We found that the long-time trapping of energy within the pair is caused by the inhibiting dark-state radiative decay when two TLSs are at half a resonant wavelength. 相似文献
994.
The [3 + 2] cycloaddition reaction between sodium azide and various organic nitriles proceeds smoothly in the presence of amine salts as catalyst in dimethylformamide. The corresponding 5-substituted 1-H tetrazoles were obtained under mild condition in good to excellent yields. Supplemental materials are available for this article. Go to the publisher's online edition of Synthetic Communications® to view the free supplemental file. 相似文献
995.
Zhou WANG Rong LAI Min PENG Saili ZHENG Lianyun LI Kejia ZHU Xianfang XU Liuping CHEN Jianxin SHI 《大学化学》2018,33(10):39-44
A survey about students' laboratory safety and environmental protection consciousness was performed in the freshmen majored in chemistry at Sun Yat-Sen University. Results showed that laboratory safety and environmental protection consciousness of most students' are weak. After analyzing the reasons, we put forward some suggestions. Cultivating students' laboratory safety and environmental protection consciousness should be carried out from several aspects such as emphasizing and regulating from school level, training in laboratory teaching, maintaining good cultural atmosphere of laboratory, as well as providing perfect laboratory safety and environmental protection facilities. We should guide students to actively learn knowledge and skills of laboratory safety and environmental protection in order to develop their good behavior and raise their consciousness. 相似文献
996.
实验探究NaOH、Na2CO3、NaHCO3这三种常见的碱基物质在模拟燃煤烟气中的实际表现,发现三种碱基物质均具有一定的脱氯性能,NaOH、Na2CO3、NaHCO3的脱氯性能依次下降,以脱氯效率70%为目标,使用三种碱基物质Na/Cl比分别需要达到5.8、7.1、8.7。高浓度SO2的存在对烟气脱氯有竞争作用,随着SO2浓度的提高,脱氯效率线性下降,不同碱基物质下,SO2浓度对脱氯效率的影响规律基本一致,SO2浓度每增加100 mg/m3,脱氯效率下降约1.4%。由于三种碱基物质达到相同脱氯效率时的Na/Cl比不同,综合考虑成本和溶解性,NaOH最具工业应用价值。 相似文献
997.
Dr. Xisen Hou Prof. Chenfeng Ke Dr. Yu Zhou Dr. Zhuang Xie Dr. Ahmed Alngadh Dr. Denis T. Keane Dr. Majed S. Nassar Dr. Youssry Y. Botros Prof. Chad A. Mirkin Prof. J. Fraser Stoddart 《Chemistry (Weinheim an der Bergstrasse, Germany)》2016,22(35):12301-12306
Covalent and supramolecular polymerizations, both of which offer their own unique advantages, have emerged as popular strategies for making artificial materials. Herein, we describe a concurrent covalent and supramolecular polymerization strategy—namely, one which utilizes 1) a bis‐azide‐functionalized diazaperopyrenium dication that undergoes polymeriation covalently with a bis‐alkyne‐functionalized biphenyl derivative in one dimension as a result of a rapid and efficient β‐cyclodextrin(CD)‐accelerated, cucurbit[6]uril(CB)‐templated azide–alkyne cycloaddition, while 2) the aromatic core of the dication is able to dimerize in a criss‐cross fashion by dint of π–π interactions, enabling simultaneous supramolecular assembly, resulting in an extended polymer network in an orthogonal dimension. 相似文献
998.
Zhigang Xue Zhen Wang Dan He Xingping Zhou Xiaolin Xie 《Journal of polymer science. Part A, Polymer chemistry》2016,54(5):611-620
Cationic emulsions of triblock copolymer particles comprising a poly(n‐butyl acrylate) (PnBA) central block and polystyrene (PS) outer blocks were synthesized by activator generated by electron transfer (AGET) atom transfer radical polymerization (ATRP). Difunctional ATRP initiator, ethylene bis(2‐bromoisobutyrate) (EBBiB), was used as initiator to synthesize the ABA type poly(styrene‐b‐n‐butyl acrylate‐b‐styrene) (PS‐PnBA‐PS) triblock copolymer. The effects of ligand and cationic surfactant on polymerizations were also discussed. Gel permeation chromatography (GPC) was used to characterize the molecular weight (Mn) and molecular weight distribution (MWD) of the resultant triblock copolymers. Particle size and particle size distribution of resulted latexes were characterized by dynamic light scattering (DLS). The resultant latexes showed good colloidal stability with average particle size around 100–300 nm in diameter. Glass transition temperature (Tg) of copolymers was studied by differential scanning calorimetry (DSC). © 2015 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2016 , 54, 611–620 相似文献
999.
Intermolecular Stetter reaction of aromatic aldehydes with (E)-(2-nitrovinyl)cyclohexane catalyzed by thiazolium A has been developed. The reaction rate and efficiency are profoundly impacted by the presence of thiourea B. The reaction affords moderate to good yields of the Stetter product. Some factors influencing yield were discussed. 相似文献
1000.