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Synthesis and Crystal Structure of a Three-dimensional (3D) Complex Mn(H_2O)_2(HNic)_2 (HNic=2-Hydroxynicotinic Acid)

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Chinese Journal of Structural Chemistry 2006年第5期25卷 572-576页

作者： li yu-mei CHE yun-Xia ZHENG Ji-Min Department of Chemistry Nankai University Tianjin 300071 China

The title complex Mn（H2O）2（HNic）2 （C22H12MnN2O8, Mr = 367.18） crystallizes in monoclinic, space group P21/c with a = 7.5735（8）, b = 12.5295（13）, c = 7.6466（8）A.β = 101.2790（10）°, Z = 2, V= 711.59（13） A^3, D, = 1.714 g/cm^3,μ（MoKa） = 0.974 mm^-1, F（000） = 374, R1 （1255 observed reflections （Ⅰ 〉 2σ（Ⅰ）） = 0.0250） and wR2 = 0.0662 （all data）. In this paper, we report the complexation of Mn（Ⅱ） by the bidentate ligand 2-hydroxynicotinic acid （HNic）. In the crystal the Mn（Ⅱ） ion exhibits a deformed octahedron structure. The title complex Mn（H2O）2（HNic）2 has a three-dimensional （3D） network structure extended by hydrogen bonds, which are formed by two typical eight-membered hydrogen-bonded rings.

关键词： complex crystal structure three-dimensional network

Fabrication and characterization of anodic oxide films on a Ti-10V-2Fe-3Al titanium alloy

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International Journal of Minerals,Metallurgy and Materials 2009年第1期16卷 96-100页

作者： Jian-hua liu Jun-lan Yi Song-mei li mei yu Yong-zhen Xu School of Materials Science and Engineering Beihang University Beijing 100191 China

Anodic oxide films of the titanium alloy Ti-10V-2Fe-3Al in ammonium tartrate electrolyte without hydrofluoric acid or fluoride were fabricated. The morphology, components, and microstructure of the films were characterized by scanning electron microscopy （SEM）, X-ray photoelectron spectroscopy （XPS）, X-ray diffraction （XRD）, and Raman spectroscopy. The results showed that the films were thick, uniform, and nontransparent. Such films exhibited sedimentary morphology, with a thickness of about 3 μm, and the pore diameters of the deposits ranged from several hundred nanometers to 1.5 μm. The films were mainly titanium dioxide. Some coke-like deposits, which may contain or be changed by OH, NH, C-C, C-O, and C=O groups, were doped in the films. The films were mainly amorphous with a small amount of anatase and rutile phase.

关键词： titanium alloys anodic oxide films titanium dioxide pulse current method

A novel TOA estimation method with effective NLOS error reduction

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The Journal of China Universities of Posts and Telecommunications 2008年第1期15卷 32-37页

作者： ZHANG Yi-heng CUI Qi-mei li yu-xiang ZHANG Ping Key Laboratory of Universal Wireless Communications Beijing University of Posts and Telecommunications Ministry of Education Wireless Technology Innovation Institute (WTI) Beijing 100876 China

It is well known that non-line-of-sight （NLOS） error has been the major factor impeding the enhancement of accuracy for time of arrival （TOA） estimation and wireless positioning. This article proposes a novel method of TOA estimation effectively reducing the NLOS error by 60%, comparing with the traditional timing and synchronization method. By constructing the orthogonal training sequences, this method converts the traditional TOA estimation to the detection of the first arrival path （FAP） in the NLOS multipath environment, and then estimates the TOA by the round-trip transmission （RTT） technology. Both theoretical analysis and numerical simulations prove that the method proposed in this article achieves better performance than the traditional methods.

关键词： TOA estimation NLOS error B3G

Fresh human amniotic membrane effectively promotes the repair of injured common peroneal nerve

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Neural Regeneration Research 2019年第12期14卷 2199-2208页

作者： Zhong-yuan Zhang Jin Yang Zhen-Hai Fan Da-li Wang yu-Ying Wang Tao Zhang li-mei yu Chang-Yin yu Key Laboratory of Cell Engineering in Guizhou Province The Affiliated Hospital of Zunyi Medical University Zunyi Guizhou Province China Department of Thyroid and Breast Surgery Fifth People’s Hospital of Chengdu Chengdu Sichuan Province China The Team of Scientific and Technological Innovation Talents on The Basic and Clinical Research of Amniotic Membrane and Bone Marrow Stem Cells in Guizhou Province Zunyi Guizhou Province China Department of Burn and Plastic Surgery The Affiliated Hospital of Zunyi Medical University Zunyi Guizhou Province China Department of Neurology The Affiliated Hospital of Zunyi Medical University Zunyi Guizhou Province China

Suture and autologous nerve transplantation are the primary therapeutic measures for completely severed nerves. However, imbalances in the microenvironment and adhesion of surrounding tissues can affect the quality of nerve regeneration and repair. Previous studies have shown that human amniotic membrane can promote the healing of a variety of tissues. In this study, the right common peroneal nerve underwent a 5-mm transection in rats. Epineural nerve repair was performed using 10/0 non-absorbable surgical suture. The repair site was wrapped with a two-layer amniotic membrane with α-cyanoacrylate rapid medical adhesive after suture. Hindlimb motor function was assessed using footprint analysis. Conduction velocity of the common peroneal nerve was calculated by neural electrical stimulation. The retrograde axoplasmic transport of the common peroneal nerve was observed using fast blue BB salt retrograde fluorescent staining. Hematoxylin- eosin staining was used to detect the pathological changes of the common peroneal nerve sputum. The mRNA expression of axon regeneration-related neurotrophic factors and inhibitors was measured using real-time polymerase chain reaction. The results showed that the amniotic membrane significantly improved the function of the injured nerve;the toe spread function rapidly recovered, the nerve conduction velocity was restored, and the number of fast blue BB salt particles were increased in the spinal cord. The amniotic membrane also increased the recovery rate of the tibialis anterior muscle and improved the tissue structure of the muscle. Meanwhile, mRNA expression of nerve growth factor, growth associated protein-43, collapsin response mediator protein-2, and brain-derived neurotrophic factor recovered to near-normal levels, while lingo-1 mRNA expression decreased significantly in spinal cord tissues. mRNA expression of glial-derived neurotrophic factor did not change significantly. Changes in mRNA levels were more significant in amniot

关键词： nerve regeneration human amniotic membrane axonal Schwann cells α-cyanoacrylate rapid medical adhesive neural suture tibial anterior muscle neuronal growth factor common peroneal nerve injury neural regeneration

Electrochemical Formation of AI-li Alloys by Codeposition of AI and li from liCI-KCI-AIF3 Melts at 853 K

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Chemical Research in Chinese Universities 2013年第2期29卷 324-328页

作者： SUN Yi ZHANG Mi-lin HAN Wei li mei YANG yu-sheng Key Laboratory of Superlight Materials and Surface Technology Ministry of Education College of Materials Science and Chemical Engineering Harbin Engineering University Harbin 150001 P. R. China

The electrochemical behavior of AI（III） ions was studied in molten liC1-KC1 melts on a molybdenum electrode. Cyclic voltammetry, chronopotentiometry and chronoamperometry were used to explore the deposition mechanism of A1 and li. Cyclic voltammetry expriment indicates that under potential deposition（UPD） of lithium on pre-deposited aluminium led to the formation of liquid A1-li alloys at 853 K. The diffusion coefficient of AI（III） ions at 853 K in liC1-KC1-AIF3（I%, mass fraction） melts was determined to be （2.79~0.05）x 10_5 cm2/s. Chronopotentio- grams and chronoamperograms demonstrate that the codeposition of AI（III） and li（I） ions formed A1-li alloys at ca- thodic current densities higher than -0.28 A/cm2 or cathodic potentials more negative than -2.20 V. X-Ray diffrac- tion（XRD） pattern indicates that A1-li alloys with different phases formed via galvanostatic electrolysis. Inductively coupled plasma（ICP） analyses of the samples obtained by electrolysis show that lithium and aluminium contents of A1-li alloys could be controlled by A1F3 concentration and current intensity.

关键词： Electrochemistry A1-li alloy Codeposition Cyclic voltammetry

Preparation and characterization of Ni-P hollow material based on the shape of Nocadia

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Chinese Science Bulletin 2008年第20期53卷 3235-3239页

作者： liANG Xin liU JianHua li Songmei yu mei WANG YanQing School of Materials Science and Engineering BeiHang University Beijing 100083 China

A new type Ni-P hollow material with rod-shape is prepared by electroless deposition method and heat treatment based on the shape of Nocadia, a kind of bacteria. The material is characterized and its magnetic, electromagnetic and mechanical properties are measured. It is found that the Ni-P coating transforms from a disordered structure before hollowing to an ordered arrangement of face centered cubic (FCC) Ni after hollowing at 673 K and body centered tetragonal Ni3P occurs. After hollowing no change of the surface morphology has been found. But the cytoplasm disappears and the Ni-P layer becomes more compact. A new type hollow material with shell thickness of 150―200 nm is obtained. The saturation magnetization (Ms), remanent magnetization (Mr) and coercivity (Hc) are enhanced to 20 emu/g, 2.7 emu/g and 117.5 Oe, respectively. The dielectric and magnetic loss are improved to 14 and 0.4, respectively. The hardness and the elastic modulus are raised to 1.80 GPa and 23.79 GPa, respectively. All show great improvement compared with those before hollowing.

关键词：镍-磷空心材料磁性绝缘体力学性质

A management information system for mine railway transportation equipment

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Journal of China University of Mining and Technology 2008年第3期18卷 373-376页

作者： li mei-yu HAN Ke-qi ZHANG Xiao-yong li Xiao-lin ZHAI Yong-jun yu Wei-hu School of Mines China University of Mining ＆ Technology Xuzhou Jiangsu 221008 China Railway Operators and Manufacturers of Shanxi Luan Mining Group Company Changzhi Shanxi 046000 China

Good equipment management is essential for the day to day management of an enterprise. Targeted at production opera-tion of the railway transportation department of a mining group and aimed at mine railway equipment management, we have estab-lished a management information system for the equipment in the entire process of the life cycle of equipment. The project deals with basic data about equipment, initial management, maintenance, operation and even disposal, based on a C/S and B/S structure. We adopted an object-oriented approach, dealing with software engineering, information engineering, economic and organizational measures. Thus, effective monitoring and control of the operation of railway equipment and its status in the entire process has been achieved.

关键词： mine railway transportation equipment management information system

On motivation and college English learning

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Sino-US English Teaching 2009年第2期6卷 33-35页

作者： li yu-mei College of Foreign Languages Daqing Petroleum Institute Daqing 163318 China

Motivation is a very important factor in English learning. So in order to help the students to maintain a proper strength in English, learning motivation is very necessary for the teachers in the daily teaching procedure. This paper discusses the issue of motivation in foreign language learning in four main sections. Finally, some suggestions are offered to the teachers.

关键词： motivation English learning some advice

Treatment of Encapsulated Blebs with Slit-Lamp Needling and Subconjunctival Interferon Injection

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Eye Science 2011年第3期26卷 138-142页

作者： Zhen Mao Xing liu Yimin Zhong Dan Cao mei li Fenfen yu State Key Laboratory on Ophthalmology Zhongshan Ophthalmic Center Sun Yat-sen UniversityGuangzhou 510060 China

Purpose:To investigate the efficacy and safety of slit-lamp needle revision with subconjunctival interferon injection in eyes with encapsulated ***:We reviewed a series of 25 cases(27 eyes) in which primary needling with 5×105 IFN α-2b injection was performed for bleb encapsulation and analysed the results over a follow-up period of at least 12 ***:The mean time to development of encapsulated blebs after the surgery was 23.85±10.66 days(9 to 60 days).The mean IOP decreased significantly from 22.51±5.30 mm Hg at diagnosis of encapsulated blebs to 17.26±7.72 mm Hg at the last visit(P=0.009).Of the 27 eyes,15(55.56%) achieved a successful result,10(37.04%) were qualified for success and the remaining 2(7.4%) were considered as *** qualified success group took 1.70±0.67 antiglaucoma *** serious complications were ***:The needling procedure associated with subconjuctival injection of IFN α-2b is a safe and effective method in treating encapsulated blebs.

关键词：注射治疗针刺过程干扰素裂隙灯眼结膜滤过包裹平均时间