Hunan Chemical Vocational Technology College

Hunan, China

Hunan Chemical Vocational Technology College

Hunan, China

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Yi W.,Hunan Chemical Vocational Technology College | Tan N.,Hunan Institute of Engineering
Acta Crystallographica Section E: Structure Reports Online | Year: 2011

In the title organometallic complex, [Sb(C 20H 23N)Cl], the central anti-mony-containing part of the complex exhibits a pseudo-trigonal-bipyramidal geometry, where two C atoms and a lone electron pair of the Sb atom exist at the equatorial positions, while the N and Cl atoms are located at the apical positions, and a transannular inter-action exists between the Sb and N atoms on 1,5-aza-stibocine. Inter-molecular C - H⋯Cl hydrogen bonds are also observed. © Yi and Tan 2011.

Zhu Z.,Hunan Chemical Vocational Technology College | Chen X.,Xiangnan University
RISTI - Revista Iberica de Sistemas e Tecnologias de Informacao | Year: 2016

The Flipped classroom is a new teaching model which is the current focus of Chinese educators. In foreign countries, there are many successful cases in the course of science courses. My team selected six classes in vocational college for teaching experiment in liberal arts courses for a period of three years. We introduce the Internet thinking, to carry out a fundamental change from teaching philosophy, teaching methods, teaching resources, the role of teachers and students, interaction and evaluation aspects, and choose to "attendance rate", "pass rate", "excellent rate", "learning satisfaction", "companies satisfaction" index as the main observation points, dynamic tracking for 306 students, so as to obtain experimental data. On this basis, we construct the Chinese flipped classroom teaching mode in "Internet plus education", and apply it to the practice of teaching. The practice proves that the flipped classroom teaching model have higher requirements and greater pressure for teachers and students, and the new teaching model is also applicable to the liberal arts courses, the effect is obviously superior to the traditional teaching. But not all courses, anything apply the teaching model. Teachers should analyze the curriculum, design and application flexible according to the characteristics of curriculum.

Zhang R.-L.,Jiangsu University of Science and Technology | Tang S.-Z.,Hunan Chemical Vocational Technology College
Materials Science Forum | Year: 2015

PbS nanocrystals was synthesized by a heterogeneous reaction of hydrogen sulfide gas and lead nitrate solution containing EDTA in ethanol. The influenceof initial molar concentration ratio of EDTA/Pb(NO3)2 (CEDTA/CPb(NO3)2), volume ratio of ethanol/water (Vethanol/VH2O), pH value and flux of H2S on the particle size of PbS were investigated. The structure, morphology, particle size, and particle size distribution ranges of PbS were characterized by XRD, FE-SEM, and laser particle size analyzer, respectively. Increasing CEDTA/CPb(NO3)2, Vethanol/VH2O, and pH value, as well as decreasing the flux of H2S decrease the particle size of PbS. PbS nanocrystals have an average particle size of 69 nm, a narrow size distribution, and a quasi-spherical shape when CEDTA/CPb(NO3)2 is 1, Vethanol/VH2O is 1, pH is 3.5, and the flux of H2S is 20 ml/min. © (2015) Trans Tech Publications, Switzerland.

Zhang R.L.,Jiangsu University of Science and Technology | Tang S.Z.,Hunan Chemical Vocational Technology College
Ultrasonics Sonochemistry | Year: 2015

The processes and conditions for ultrasonic preparation of cubic Sb 2O3 crystals under ultrasonic by neutralizing Sb 4O5Cl2 with ammonium hydroxide were researched. The effects of ultrasonic power, time and temperature as well as ratio of Sb4O5Cl2 to water on the crystal form and particle size of Sb2O3 were investigated by X-ray diffraction, scanning electron microscopy and laser particle size analyzer. Cubic Sb2O3 crystals were prepared by being sonicated at 100 W and 20 °C for 30 min. The particles were cubic-like, with the average size of 0.777 μm. © 2014 Elsevier B.V. All rights reserved.

Ying T.,Hunan Chemical Vocational Technology College
Proceedings - 2013 4th International Conference on Digital Manufacturing and Automation, ICDMA 2013 | Year: 2013

This thesis further study descent conjugate gradient methods based on the modified FR method and the modified PRP method give the class of conjugate gradient methods formed by the convex combination of the MFR method and the MPRP method. This class of methods enjoys the same nice properties as those of the MFR method and the MPRP method. Firstly the methods generate sufficient descent directions for the objective function. This property is independent of the line search used. Secondly if exact line search is used, the methods possess quadratic termination property. Thirdly if Armijo type line search is used, then the methods are globally convergent when used to minimize a general nonconvex function. Finally, we do extensive numerical experiments to test the performance of the members in the class with different parameters. And then compare the performance of one of the method in the class with the MFR method and the MPRP method. © 2013 IEEE.

Peng X.-R.,Hunan Chemical Vocational Technology College
Proceedings - 2013 4th International Conference on Digital Manufacturing and Automation, ICDMA 2013 | Year: 2013

With outside disturbing effects, large hydraulic straightening machine's total load changes intricately and its precision is less than ideal requirements when being straightened. This paper preposes the fuzzy control strategy, and realizes high-precision control of the straightening machine. © 2013 IEEE.

Li J.,Hunan Chemical Vocational Technology College
Advanced Materials Research | Year: 2012

In this paper, a precipitation method is investigated to prepare nanoscale zinc oxide (ZnO) as the precursor of silver coated antibacterial nanocomposite. Subsequently, silver loadeded zinc oxide nanocomposites (ZnO/Ag) are prepared by hydrolysis method. The average diameters and morphology of ZnO nanocomposites before and after silver loaded were compared. The results showed that the zinc oxide powder presented good dispersibility and uniform size a average diameter of 170 nm. Silver was coated on the precursor successfully, and the diameter of ZnO nanocomposites increased slightly.

Yan D.,Hunan Chemical Vocational Technology College | Tong M.,Hunan Chemical Vocational Technology College
Gaodeng Xuexiao Huaxue Xuebao/Chemical Journal of Chinese Universities | Year: 2016

The formation of C-S bonds is one of the most important transformations in organic chemistry due to the high prevalence of sulfur-containing molecules of biological and pharmaceutical relevance. Cross-dehydrogenative coupling (CDC) is more atom economical and environmentally friendly than traditional cross-coupling reactions. A facile and transition metal-free methodology for construction of C (sp3)-S bond was herein reported. With ditertbutyl peroxide (DTBP) as oxidant and thiophenol as thioetherification regent under 120 ℃, the high atom-efficiency and selective system offered the thiobenzylethers as products in acceptable to good yields. These new compounds were characterized via infrared (IR), nuclear magnetic resonance (NMR), and mass spectrometry (MS). The possible mechanism for the reaction was suggested as followed: benzyl ethers was oxidized by DTBP to generate intermediates A, which further reacted with thiophenol to form desired products. This direct thiolation method is a new protocol for the construction of C-S bonds, which might be very valuable and attractive in sulfur chemistry and radical chemistry. © 2016, Higher Education Press. All right reserved.

Xia Y.,Hunan Chemical Vocational Technology College
Advanced Materials Research | Year: 2013

Industry is the foundation of national economy and military development, and machinery manufacture and production is the main content of industry. Therefore, each country attaches great importance to its own machinery manufacture capacity and production levels. Influenced by the special historical factors, China's economy started relatively late, with a low machinery manufacture capacity. To essentially change this phenomenon, the selection and processing technology of metal materials must be optimized. This paper analyzes the concept and characteristics of metal mechanics, together with the present situation of China's machinery manufacture and production. After studying the relationship between metal mechanical and machinery manufacture and production, it is found that the use of metal mechanics can improve the quality of mechanical products. © (2013) Trans Tech Publications, Switzerland.

Li J.,Hunan Chemical Vocational Technology College
Proceedings - 2010 International Conference on Digital Manufacturing and Automation, ICDMA 2010 | Year: 2010

Calcium carbonate nanopowder is an important engineering material used for various painting and polymer-based composite additive and filler. The hydrophobic modification on surface of calcium carbonate nanopowder was performed by using three silane coupling agents: i.e. 3-Aminopropyl triethoxysilane (APTES), 3-mercapto-propyl triethoxysilane (MPTES) and 3-ATRP trimethoxysilane (KH570). The Fourier Transform Infrared Spectrometry (FT-IR) was used to confirm the surface chemical coupling variations. The contact angle meter was used to determine its hydrophobic property. After KH570 modification, the sample of nanopowder showed the best hydrophobic property with a contact angle of 107° . The findings are of significance to enhance nano-calcium carbonate dispersibility and compatibility in organic media. © 2010 IEEE.

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