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91.
采用分子动力学模拟方法研究了298.15 K、0.1 MPa下摩尔分数为0.1-0.9 的甲醇对1-丁基-3-甲基咪唑四氟硼酸盐([BMIM][BF4])结构与性质的影响. 获得了体系的密度、径向分布函数、配位数、自扩散系数、粘度和电导率, 模拟得到的密度值与实验值符合较好. 结果显示: 体系各组分之间的径向分布函数随甲醇摩尔分数的增加呈规律性变化; 体系内阴阳离子的自扩散系数随着甲醇摩尔分数的增加不断增大; 甲醇的加入削弱了阴阳离子之间的相互作用, 体系粘度随着甲醇摩尔分数的增加逐渐减小, 电导率不断增大. 分析空间分布函数得到体系中各组分的三维空间分布情况. 相似文献
92.
利用离子液体1-丁基-3-甲基咪唑四氟硼酸盐(BMIMBF4)对玻碳电极(GCE)进行修饰,制备了BMI-MBF4/GCE电极.在0.1mol/L的磷酸盐缓冲溶液中,采用循环伏安法研究了抗坏血酸在BMIMBF4/GCE电极和裸玻碳电极(GCE)上的电化学行为.结果表明,pH=5.7的磷酸盐缓冲溶液为最佳测定底液,最佳富集时间为120s;BMIMBF4/GCE对抗坏血酸的氧化反应有很好的电化学催化作用.抗坏血酸的氧化峰电流与其浓度在2.0×10-4~1.0×10-2 mol/L的范围内呈良好的线性关系,相对标准偏差为4.53%(n=5). 相似文献
93.
94.
Ahmed Kamal R. Ramu Mohd. Ameruddin Azhar G.B. Ramesh Khanna 《Tetrahedron letters》2005,46(15):2675-2677
Copper(II) tetrafluoroborate catalyzes efficiently the selective opening of epoxides by amines leading to the synthesis of β-amino alcohols. The reaction works well with aromatic and aliphatic amines in high yields under solvent-free conditions. 相似文献
95.
I. V. Kravtsov P. A. Belyakov S. V. Baranin V. A. Dorokhov 《Russian Chemical Bulletin》2007,56(8):1561-1565
A convenient method for the synthesis of 6-R-3-arylazo-1H-pyridazin-4-ones from difluoroboron chelates of acetylacetone and aroylacetones was developed. The method is based on the
ability of the methyl group of the chelates to react with two equivalents of a diazonium salt.
Dedicated to Academician V. A. Tartakovsky on the occasion of his 75th birthday.
Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 8, pp. 1502–1506, August, 2007. 相似文献
96.
97.
A New Structural Motif for an Enantiomerically Pure Metallosupramolecular Pd4L8 Aggregate by Anion Templating 下载免费PDF全文
M. Sc. Christoph Klein Dr. Christoph Gütz Maximilian Bogner M. Sc. Filip Topić Prof. Dr. Kari Rissanen Prof. Dr. Arne Lützen 《Angewandte Chemie (International ed. in English)》2014,53(14):3739-3742
An enantiomerically pure BINOL‐based bis(3‐pyridyl) ligand 1 assembles into a homochiral [Pd4( 1 )8] complex upon coordination to tetravalent PdII ions. The formation of this aggregate is templated by two tetrafluoroborate counterions that are encapsulated in two peripheral cavities. The resulting structure is a new structural motif for this kind of metallosupramolecular assemblies that arranges the palladium ions in a distorted tetrahedral fashion and forces ligand 1 to adopt two different conformations. Both phenomena are unique and cause an overall three‐dimensional structure that has another confined, chiral, and hydrophilic central cavity. 相似文献
98.
A new and progressive electroanalytical sensor was made by the incorporation of Pt‐doped NiO nanoparticle (Pt‐NiO‐NPs) into carbon paste electrode (CPE) amplified with 1‐hexyl‐3‐methylimidazolium tetrafluoroborate (1H3MTFB) as a conductive binder. The Pt‐NiO‐NPs/1H3MTFB/CPE caused an extraordinary rise in the oxidation peak current of epinine (~4.6 times) and simultaneous reduction in the oxidation over‐potential of catecholamine drug (~120 mV). SWV method was employed to investigate the ability of Pt‐NiO‐NPs/1H3MTFB/CPE as an electroanalytical sensor in the determination of epinine in the presence of phenylephrine as two blood pressure raising drugs with ΔE=280 mV for the first time. Experimental results pertinent to SW voltammetric investigation reveal a linear relation between epinine and phenylephrine currents and drugs concentration in the rages 0.004–450 and 0.02–350 μM, respectively. 相似文献
99.
KAMBLE Vinod Tribhuvannathji BANDGAR Babasaheb Pandurang BAVIKAR Sudhir Narayanrao 《中国化学》2007,25(1):13-15
Sodium tetrafluoroborate (NaBF4) was found to catalyze the electrophilic substitution reactions of indoles with aldehydes and ketones under solvent-free conditions to afford the corresponding bis(indolyl)methanes in high yields. 相似文献
100.
Koji Hoshino Masafumi Yoshio Tomohiro Mukai Kenji Kishimoto Hiroyuki Ohno Takashi Kato 《Journal of polymer science. Part A, Polymer chemistry》2003,41(22):3486-3492
An ion-conductive mesogenic monomer with an imidazolium ionic moiety has been designed to obtain self-assembled materials forming ionic layers. Self-standing polymer films are prepared by in situ photopolymerization of the monomer that forms homeotropic monodomain on a normal glass substrate in the smectic A phase. Macroscopically oriented, layered nanostructures are formed in the film. The ionic conductivity parallel to the smectic layer has been measured for the oriented film. In the smectic A phase at 150 °C, the magnitude of conductivity is about 10−2 S cm−1. © 2003 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 41: 3486–3492, 2003 相似文献