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101.
FuYouLI XiaoRongZOU ChunHuiHUANG 《中国化学快报》2003,14(6):641-644
A novel dye dimer,bis-{[1-(N-hexadecyl-4-pyridinium)-2-(4-N,N-dimethylaminopheyl)] ethenyl} methane diiodide (C16BP) was synthesized,and the photoelectrochemistry of the dye Langmuir-Blodgett monolayer modified ITO electrode was investigated.For comparison,the photoelectrochemistry of the monomer (E)-N-hexadexyl-4-[2-(4-N,N-dimethylaminophenyl) ethenyl] pyridinium iodide (C16P) was also measured.The results show that the photocurrent generation property of the dimer is enhanced.The photocurrent generation quantum yield is 0.38% for C16BP,while that for C16P is 0.23%. 相似文献
102.
用毛细管离子分析 (CIA)法 ,采用 10mmol·L- 1咪唑为背景电解质 ,4 0 %甲醇为选择性改性剂 ,在 pH 2 .5、分离电压为 2 5kV、柱温为 2 2℃的电泳条件下 ,采用间接紫外检测 (2 14nm ) ,在5min内测定了人发中铝 ,方法简便、快速、灵敏度高、重现性好、测定成本低 相似文献
103.
Summary A clean method without use of organic solvents has been developed for isolation and high-performance liquid chromatographic
(HPLC) determination of oxytetracycline (OTC) and sulphadimidine (SDD) in cow's milk. Isolation is rapid and simple—homogenization
with an inorganic acid solution by means of a handy ultrasonic homogenizer, which is easy-to-use and portable, followed by
centrifugation. Reversed-phase HPLC was performed on a C4 column, with 1.25 mmol L−1 succinic acid solution as mobile phase, and identification was by means of a photodiode-array detector. Separation of the
analytes was achieved in less than 8 min. Significant linearity was established over the concentration range of 0.1–1.0 μg
mL−1 for both target compounds (r>0.99,P<0.01). Average recoveries of OTC and SDD (each spiked at 0.1–1.0 μg mL−1) were ≥88.8, and inter- and intra-assay variability was ≤2.8%. The total time required for analysis of one sample was <20
min. The limits of quantitation of the method (μg mL−1 in milk) were 0.044 for OTC and 0.023 for SDD. No organic solvent was used at any stage of the analysis. 相似文献
104.
Guo-Xia Jin Tian-Chao You Jian-Ping Ma 《Acta Crystallographica. Section C, Structural Chemistry》2019,75(12):1690-1697
The new asymmetrical organic ligand 2‐{4‐[(1H‐imidazol‐1‐yl)methyl]phenyl}‐5‐(pyridin‐4‐yl)‐1,3,4‐oxadiazole ( L , C17H13N5O), containing pyridine and imidazole terminal groups, as well as potential oxdiazole coordination sites, was designed and synthesized. The coordination chemistry of L with soft AgI, CuI and CdII metal ions was investigated and three new coordination polymers (CPs), namely, catena‐poly[[silver(I)‐μ‐2‐{4‐[(1H‐imidazol‐1‐yl)methyl]phenyl}‐5‐(pyridin‐4‐yl)‐1,3,4‐oxadiazole] hexafluoridophosphate], {[Ag( L )]PF6}n, catena‐poly[[copper(I)‐di‐μ‐iodido‐copper(I)‐bis(μ‐2‐{4‐[(1H‐imidazol‐1‐yl)methyl]phenyl}‐5‐(pyridin‐4‐yl)‐1,3,4‐oxadiazole)] 1,4‐dioxane monosolvate], {[Cu2I2( L )2]·C4H8O2}n, and catena‐poly[[[dinitratocopper(II)]‐bis(μ‐2‐{4‐[(1H‐imidazol‐1‐yl)methyl]phenyl}‐5‐(pyridin‐4‐yl)‐1,3,4‐oxadiazole)]–methanol–water (1/1/0.65)], {[Cd( L )2(NO3)2]·2CH4O·0.65H2O}n, were obtained. The experimental results show that ligand L coordinates easily with linear AgI, tetrahedral CuI and octahedral CdII metal atoms to form one‐dimensional polymeric structures. The intermediate oxadiazole ring does not participate in the coordination interactions with the metal ions. In all three CPs, weak π–π interactions between the nearly coplanar pyridine, oxadiazole and benzene rings play an important role in the packing of the polymeric chains. 相似文献
105.
Iseul Jeong Chae Bin Kim Dong‐Gue Kang Kwang‐Un Jeong Se Gyu Jang Nam‐Ho You Seokhoon Ahn Dai‐Soo Lee Munju Goh 《Journal of polymer science. Part A, Polymer chemistry》2019,57(6):708-715
To address tremendous needs for developing efficiently heat dissipating materials with lightweights, a series of liquid crystalline epoxy resins (LCEs) are designed and synthesized as thermally conductive matrix. All prepared LCEs possess epoxies at the molecular side positions and cyanobiphenyl mesogenic end groups. Based on several experimental results such as differential scanning calorimetry, polarized optical microscopy, and X‐ray diffraction, it is found that the LCEs exhibited liquid crystalline mesophases. When LCE is cured with a diamine crosslinker, the cured LCE maintains the oriented LC domain formed in the uncured state, ascribing to a presence of dipole–diploe and π–π interactions between cyanobiphenyl mesogenic end groups. Due to the anisotropic molecular orientation, the cured LCE exhibits a high thermal conductivity of 0.46 W m?1 K?1, which is higher than those of commercially available crystalline or amorphous epoxy resins. © 2018 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2019 , 57, 708–715 相似文献
106.
Jianhao Wang Zhilan Zhu Wenjing Jia Lin Qiu Yufeng Chang Jie Li Luping Ma Ying You Jianpeng Wang Li Liu Jiang Xia Xiaoqian Liu Yong‐Qiang Li Pengju Jiang 《Electrophoresis》2019,40(7):1019-1026
Despite the numerous techniques developed for the studying nanoparticle and peptide interaction nowadays, sensitive and convenient assay in the process of flow, especially to simulate the self‐assembly of quantum dots (QDs) and peptide inflow in blood vessels, still remains big challenges. Here, we report a novel assay for studying the self‐assembly of QDs and peptide, based on CE using a bending capillary. We demonstrate that the semicircles numbers of the bending capillary affect the self‐assembly kinetics of CdSe/ZnS QDs and ATTO‐D3LVPRGSGP9G2H6 peptide. Moreover, benefitting from this novel assay, the effect of the position on the self‐assembly has also been realized. More importantly, we also demonstrate that this novel assay can be used for studying the stability of the QDs–peptide complex inflow. We believe that our novel assay proposed in this work could be further used as a general strategy for the studying nanoparticle–biomolecule interaction or biomolecule–biomolecule interaction. 相似文献
107.
Yi Lanhua Hu You Fei Junjie Li Juan Yang Chunguang Wang Xianyou 《Journal of Solid State Electrochemistry》2019,23(6):1739-1748
Journal of Solid State Electrochemistry - Pd/C and Pd-Co/C nanocatalysts are prepared via a simple and environmentally friendly method and are used as anodic catalyst for direct... 相似文献
108.
制备了α-MnO2纳米管作为硫的宿主材料,将硫填充到α-MnO2管的中空部分,并通过原位聚合法在α-MnO2外层包覆一层薄层聚(3,4-乙烯二氧噻吩)(PEDOT)进一步束缚硫。这样一种双重固硫的阴极材料S@α-MnO2-PEDOT在锂硫电池中体现出了高的性能。在电流密度1 675 mA·g-1(1C)下循环200圈,容量为774.4 mAh·g-1,且在电流密度为3 350 mA·g-1(2C)下容量达854.1 mAh·g-1,体现出良好的循环稳定性和倍率性能。这些显著的性能得益于阴极材料新颖的结构。在这种结构中,α-MnO2纳米管不仅能对硫起到物理限制作用,而且增强了硫宿主材料和多硫化物间的化学相互作用。同时,PEDOT的引入增强了含硫纳米复合材料的导电性,并进一步减少了由于体积变化和多硫化锂的过度溶解引起的硫的损失。 相似文献
109.
A simple, rapid and sensitive liquid chromatography/electrospray tandem mass spectrometry (LC-MS/MS) quantitative detection method, using cefalexin as internal standard, was developed for the analysis of faropenem in human plasma and urine. After precipitation of the plasma proteins with acetonitrile, the analytes were separated on a C18 reversed-phase column with 0.1% formic acid-methanol (45:55, v/v) and detected by electrospray ionization mass spectrometry in positive multiple reaction monitoring mode. Calibration curves with good linearities (r=0.9991 for plasma sample and r=0.9993 for urine sample) were obtained in the range 5-4000 ng/mL for faropenem. The limit of detection was 5 ng/mL. Recoveries were around 90% for the extraction from human plasma, and good precision and accuracy were achieved. This method is feasible for the evaluation of pharmacokinetic profiles of faropenem in humans, and to our knowledge, it is the first time the pharmacokinetic of faropenem has been elucidated in vivo using LC-MS/MS. 相似文献
110.
Heller B Sundermann B Buschmann H Drexler HJ You J Holzgrabe U Heller E Oehme G 《The Journal of organic chemistry》2002,67(13):4414-4422
The photocatalyzed [2 + 2 + 2]-cycloaddition of nitriles with 2 equiv of acetylene to 2-pyridines can be carried out under mild conditions and represents a valuable extension to common synthetical methods. For the ideal wavelength range (350-500 nm), lamps as well as sunlight can be used. Working at room temperature and in organic solvents such as toluene or hexane as well as in water gives satisfying results in many cases. However, it is also possible to vary the solvent and the reaction temperature of the photocatalyzed synthesis and to choose, with respect to the specific substrate, specific requirements for this particular reaction and general requirements of the method. This simple and selective method derives its potential mainly from the large variety of applicable nitriles. Suitable substrates include (functionalized) aliphatic and aromatic nitriles as well as cyanamides derived from secondary amines. 相似文献