Search Options

Sort by:

Sort search results by

Publication Type:

Publication Type filter

Open access:

Publication Date:

Periodicals:

Periodicals filter

Search results

Online since: June 2013
Authors: Xiao Qing Guo, Li Jun Qu, Ming Wei Tian, Yan Zhang, Xiao Jing Bao
Test instruments APEX microwave chemistry studio (PreeKem Co., Ltd); electronic balance (Mettler-Toledo Shanghai Instrument Co., Ltd); Y801A basket conditioning oven (Laizhou Electron Instrument Co., Ltd); electron all-purpose heat (Tianjin Taisite Instrument Co., Ltd) Experiment reagents Sulfuric acid (98%, analytically pure), sodium hydroxide (analytically pure), hydrogen peroxide (30%, analytically pure), hydrogen peroxide stabilizer Test method: chemical component and residual gum content can be tested by depending on chemical component quantitative analysis method of GB 5889—1986 ramie.
The swelling volume of fibrin enlarged along with the increase of NaOH concentration, while the fibrin strength reduced [4] due to that the macromolecular structure of fibrin was inhomogeneous, glycosidic linkage had various stability to chemical medicine and resulted in a certain damage to chemical bond, furthermore, the overtop alkali concentration also resulted in the damage of fiber and lowered the strength of it.
It can be concluded that the fiber surface obtained electric charge with double-layer structure when touching with aqueous solution as per interface moving electrochemistry irradiation double potential theory of cellulosic fiber in aqueous biphasic system, as well as that the chemical potential in alkali liquor was prominently higher than abelmoschus manihot fiber system.
Online since: November 2007
Authors: Tae Young Yang, Seog Young Yoon, Hong Chae Park, Ron Stevens, B.M. Kim
The crystal structure of the whiskers with a nanometer-sized diameter (~160 nm) was shown by observation of TEM and microbeam diffraction (Fig. 4), to be orthorhombic.
mullite is restricted to a molar ratio of Al2O3/SiO2 = 1.02, but could be due to the crystal chemistry, or possibly be due to a mixture of whiskers of different composition, which would be averaged out in an EDS beam analysis in the SEM.
The resulting mullite whiskers exhibited an aspect ratio of >30 (0.2-0.4 μm in diameter), and had a composition of 62.9 wt% Al2O3 and 37.1 wt% SiO2, with an orthorhombic-type structure.
Online since: February 2011
Authors: Wei Qiao Liu, Xing Xing Wang, Bo Jiang, Wei Ning Lei
It could be concluded that the ultrasound and mechanical agitation can promote the ions transport, then the crystal grains are dispersed evenly in the coating and the caking phenomenon disappears, so the crystallizations of electroforming coating can refine remarkably and keep a compact structure, the bonding between them are tight [6].
Table 2 Microhardness of electroforming deposits under different process conditions Addition of Al2O3 particles Microhardness with mechanical agitation Microhardness with ultrasonic and agitation 0.0 [g L-1] 220.5 [HV] 254.8 [HV] 2.5 [g L-1] 350.7 [HV] 373.7 [HV] 3.5 [g L-1] 401.1 [HV] 413.3 [HV] 5.0 [g L-1] 410.5 [HV] 461.9 [HV] Conclusions The grain size of electroforming deposits is reduced and hardly cavities with ultrasonic and agitation, the coating possesses a compact structure and the bonding between grains is tight.
Compton: Journal of Electroanalytical Chemistry Vol. 531 (2002), p. 19 [11] K.
Online since: January 2010
Authors: Qing Yan, Ke Qing Zhao, Ping Hu, Bi Qin Wang, Wen Hao Yu
Synthesis and mesomorphism of 1,1'-disubstitued ferrocene liquid crystals with a schiff's base bridge Qing Yan, Ping Hu, Wen-Hao Yu, Bi-Qin Wang and Ke-Qing Zhaoa College of Chemistry and Materials Science, Sichuan Normal University, Chengdu 610066, China a kqzhao@sicnu.edu.com Keywords: Ferrocene; Metallomesogen; Liquid crystal; Nematic phase Abstract.
The diverse structures of ferrocene metallomesogens can be classified as monosubstituted, 1,1'-, 1,2- and 1,3-disubstituted, 1,1',3-trisubstituted [5-17].
Fortunately, this repulsion effect could be weakened through changing the structure of the ferrocene derivatives.
Online since: January 2010
Authors: Yuan Ming Huang, Qing Lan Ma, Bao Gai Zhai
In spite of the great progress has been achieved in the past thirteen years in understanding the physics and chemistry in bent-core LCs, the influence of cooling rates on the phase transitions of bent-core LCs has not been touched.
Results and discussion Figure 1 depicts the synthesis and molecular structure of the three benzene-ring containing bent-core compound 1,3-phenylene-bis[4-(alkylcarboyloxyl)benzylideneamine].
Synthetic scheme and molecular structure of the three-benzene-ring containing bent-core compound 1,3-phenylene-bis[4-(hexylcarboyloxyl)benzylideneamine].
Online since: April 2010
Authors: Li Yun Cao, Jian Feng Huang, Xie Rong Zeng, Ya Qin Wang
Influence of Deposition Voltage on Microstructures of Yttrium Silicates Coatings by Hydrothermal Electrophoretic Deposition Wang Ya-qina 1, Huang Jian-fengb 1,2, Cao Li-yun1 and Zeng Xie-rong2 1 Key Laboratory of Auxiliary Chemistry & Technology for Chemical Industry, Ministry of Education, Shaanxi University of Science & Technology, Xi'an Shaanxi 710021, China 2 Shenzhen Key Laboratory of Special Functional Materials, Shenzhen University, Shenzhen, Guangdong 518086, China a wangyaqinheart@yahoo.com.cn, bhuangjf@sust.edu.cn Keywords: Hydrothermal electrophoretic deposition; C/C composites; Yttrium silicates coatings Abstract.
The coating phase structures were analyzed by X-ray diffraction (XRD).
The observations indicate that anticipative coatings structures can be controlled through adjusting deposition voltage during the hydrothermal electrophoretic process.
Online since: November 2011
Authors: Yi Ping Zhong, Ping Liu, Wen Ji Deng, Li Guan, Xue Quan Zhao
Synthesis and Electrochromic Properties Based on Star-shaped Oligothiophene Derivatives with Phenyl Core Li Guan1,2, Xue-quan Zhao1, Yi-ping Zhong1, Ping Liu1,a and Wen-ji Deng3,b 1State Key Laboratory of Physics and Chemistry of Luminescence, Research Institute of Materials Science, South China University of Technology, Guangzhou 510640, P.
Introduction Oligothiophenes with well defined structures have recently received a great deal of attention not only as model compounds for conducting polythiophenes, but also as a new class of functional-electron systems.
A variety of oligothiophenes have been synthesized [1-3] and their molecular and crystal structures, self ordering, electrochemical, photophysical, optical, and electrical properties have all been studied.
Online since: October 2014
Authors: Chang Qing Tu, Xin Rong Wen
Spectrophotometric Determination of Isoniazid in Pharmaceutical Sample by Silicomolybdenum Blue Xinrong Wena and Changqing Tub College of Chemistry and Environment,Jiaying University,Meizhou, Guangdong 514015, P.
Introdution Isoniazid (the molecular structure of isoniazid is shown in Fig. 1) is mainly used for the treatment of various tuberculosis,the metabolites can cause liver damage[1].
The molecular the determination of isoniazid, such as titration method[2],HPLC structure of isoniazid method[3,4],electrochemical analysis method[5,6],capillary elec- trophoretic method[7,8], fluorescence spectrum method[9], etc.In this paper, we developed a novel method for the indirect determination of isoniazid in pharmaceutical sample by silicomolybdenum blue.Under certain reaction conditions,silicomolybdenum yellow could be reduced to silicomolybdenum blue by isoniazid, and the content of isoniazid was determinated indirectly through determinating the absorbance of the silicomolybdenum blue.
Online since: October 2014
Authors: Qi Sun, Shan Shan Gong, Xiao Chuan Li
Preparation of Bis-functionalized 1,4-Diaminobutane Derivatives Xiaochuan Lia, Shanshan Gongb, Qi Sunc,* Jiangxi Key Laboratory of Organic Chemistry, Jiangxi Science and Technology Normal University 605 Fenglin Avenue, Nanchang, Jiangxi 330013, PR China aemail: 985037753@qq.com, bemail: gongshanshan33@gmail.com, cemail: sunqi96@tsinghua.org.cn Keywords: Kabachnik-Fields reaction; Phosphonate; Imine; Solvent-free Abstract.
Natural bolaamphiphiles in the membranes of many bacteria can form very rigid structures, which enable the survival of the microorganisms under tough environments.
The chemical structures of the three bis-functionalized 1,4-diaminobutane derivatives 6–8 were characterized by NMR and high resolution mass spectrometry.
Online since: November 2011
Authors: Chun Hu Li, Jia Ling Chen, Ying Wei Luo, Jian Peng Zhu
Desulfurization from Gasoline by Polymer Resin at Room Temperature and Atmospheric Pressure Jianpeng Zhu1,a, Chunhu Li1,b, Jialing Chen1,c , Yingwei Luo1,d 1 Key Laboratory of Marine Chemsitry Theory and Technology, Ministry of Education, College of Chemistry and Chemical Engineering, Ocean University of China, Qingdao 266100, PR China aforce-79469@163.com , blichunhu@ouc.edu.cn cchenjialing1224@163.com, dbaby1985720@tom.com Keywords: Resin; Gasoline; Oxidative desulfurization; Adsorption; H2O2; Sulfur compounds Abstract.
Strongly acidic macroporous ion exchange resin exhibits strong acidic and has macroporous structure, this kind of resin may have an advantage in this regard over other adsorbents or catalysts because of the dual abilities.
It may be attributed that H2O2 show intensity oxidation at high temperature, which could destroy the structure of polyer resin.