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Effects of Pb^(2+), Cd^(2+) and Cu^(2+) on the Aqueous Zn^(2+) Sorption by Hydroxyapatite

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Acta Geologica Sinica(English Edition) 2006年第2期80卷 226-229页

作者： QI yong liu yu School of Material Science and Technology Wuhan Institute of Technology Wuhan Hubei 430073

In this paper, the behaviors of aqueous zinc sorption by hydroxyapatite in the co-existence of Pb^2＋, Cd^2＋ and Cu^2＋ are investigated, the effects of Pb^2＋, Cd^2＋ and Cu^2＋ on the sorption of Zn^2＋ are discussed, and the hydroxyapatite sorption capabilities for Pb^2＋, Cd^2＋, Cu^2＋ and Zn^2＋ are compared. The experimental results show that the Zn^2＋ removal efficiency decreases gradually with the increase of the Cd^2＋ concentration of the solution, and there is no sorption preference between Cd^2＋ and Zn^2＋. On the other hand, the Zn^2＋ removal efficiency rapidly decreases rapidly with the increase of the Cu^2＋ concentration of the solution, and there is a clear sorption preference between Cu^2＋ and Zn^2＋. It is noticed that the Zn^2＋ removal efficiency is hardly changed with the variance of Pb^2＋ concentration because the removal mechanisms for these two ions are totally different. It is concluded that the adsorption affinities of the heavy metals for the hydroxyapatite follows this sequence： pb^2＋〉 Cu^2＋〉 Cd^2＋〉 Zn^2＋.

关键词： hydroxyapatite heavy metal ions sorption hydroxyapatite heavy metal ions sorption

Efficient implementation of a cubic-convolution based image scaling engine

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Journal of Zhejiang University-Science C(Computers and Electronics) 2011年第9期12卷 743-753页

作者： Xiang WANG yong DING Ming-yu liu Xiao-lang YAN Institute of VLSI Design Zhejiang University Hangzhou 310027 China

In video applications, real-time image scaling techniques are often required. In this paper, an efficient implementation of a scaling engine based on 4×4 cubic convolution is proposed. The cubic convolution has a better performance than other traditional interpolation kernels and can also be realized on hardware. The engine is designed to perform arbitrary scaling ratios with an image resolution smaller than 2560× 1920 pixels and can scale up or down, in horizontal or vertical direction. It is composed of four fimctional units and five line buffers, which makes it more competitive than conventional architectures. A strict fixed-point strategy is applied to minimize the quantization errors of hardware realization. Experimental results show that the engine provides a better image quality and a comparatively lower hardware cost than reference implementations.

关键词： Cubic-convolution Hardware implementation Interpolation Engine

Synthesis and Crystal Structure of the Copper Complex {[Cu(CH_3COO)_2(bbtz)](H_2O)_2}_n

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Chinese Journal of Structural Chemistry 2005年第10期24卷 1129-1132页

作者： ZHANG yong ZHANG yu-Mei liu Xun-Gao LI Bao-Long Key Laboratory of Organic Synthesis of Jiangsu Province College of Chemistry and Chemical Engineering Suzhou University Suzhou 215123 China

The new copper complex { [Cu（CH3COO）2（bbtz）]（H2O）2 }, 1 （bbtz = 1,4-bis（ 1,2,4- triazol-1-ylmethyl）benzene） was synthesized and the structure was determined by single-crystal X-ray diffraction. Crystal data： C16H22CuN6O6, monoclinic, space group P21/n, a = 12.589（5）, b = 6.455（2）, c = 12.677（5） A, β= 98.748（9）°, V= 1018.2（7） A^3, Mr = 457.95, Z = 2, Dc= 1.494 g/cm^3, F（000） = 474, μ = 1.118 mm^-1, R = 0.0463 and wR = 0.0939 for 1971 observed reflections with I 〉 2σ（I）. The crystal structure of 1 is a one-dimensional chain via the bridging flexible ligand bbtz.

关键词： crystal structure copper complex triazole ligand synthesis

Analysis of Norditerpenoid Alkaloids Extracted from Aconitum sinomantanum Nakai by Electrospray Ionization Tandem Mass Spectrometry

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Chemical Research in Chinese Universities 2006年第3期22卷 343-346页

作者： XU Qing-xuan yuE Hao liu Zhi-qiang WANG yong YAN Cun-yu liu Shu-ying Changchun Institute of Applied Chemistry Chinese Academy of Sciences Changchun 130022 P. R. China

Electrospray ionization mass spectrometry（ESI-MS） was applied simultaneously in determining norditerpenoid alkaloids from the roots of Aconitum sinomantanum Nakai （RAS） based on molecular mass information. The tandem mass spectra（ ESI-MS^n） provided the alkaloidal structural information, through which the existence of these alkaloids was further confirmed. Accordingly, six known norditerpenoid alkaloids were simultaneously determined on the basis of their ESI-MS^n spectra. Furthermore, based on the diagnostic fragmentation pathways of alkaloidal MS^n, a rapid method for direct detection and characterization of alkaloids from an ethanolic extract of RAS was described.

关键词： Electrospray ionization tandem mass spectrometry( ESI-MS^n) Norditerpenoid alkaloid Aconitum sinomantanum Nakai

Prediction of Rolling Load, Recrystallization Kinetics, and Microstructure During Hot Strip Rolling

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Journal of Iron and Steel Research International 2007年第6期14卷 42-46页

作者： XU yun-bo yu yong mei liu Xiang-hua WANG Guo-dong State Key Laboratory of Rolling and Automation Northeastern University Shenyang 110004 Liaoning China

The recrystallization kinetics and grain size models were developed for the C Mn and niobium containing steels to describe the metallurgical phenomenon such as softening, grain growth, and strain accumulation. Based on the recrystallization kinetics equations, the mean flow stress and the rolling load of each pass were predicted and the optimum rolling schedule was proposed for hot strip rolling. The austenite grain refinement is associated with the addition of niobium, the decrease of starting temperature of finish rolling, and the reduction of finished thickness. The mean flow stress curve with a continuous rising characteristic can be usually observed in the finish rolling of niobium containing steel, which is formed as a result of the heavy incomplete softening and strain accumulation. The predic ted rolling loads are in good agreement with the measured ones.

关键词： hot strip rolling recrystallization mean flow stress strain accumulation grain size

Computer Model of Phase Transformation From Hot-Deformed Austenite in Niobium Microalloyed Steels

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Journal of Iron and Steel Research International 2007年第2期14卷 66-69页

作者： XU yun-bo yu yong-mei liu Xiang-hua WANG Guo-dong State Key Lab of Rolling and Automation Northeastern University Shenyang 110004 Liaoning China

Based on thermodynamics and kinetics, a new mathematical model was developed to calculate the CCT diagrams and the transformation kinetics in low carbon niobium steels, in which the effect of deformation on the degree of supercooling was taken into account. The undercooling caused by deformation is the major reason for the increase of the starting transition temperature during continuous cooling. The critical cooling rate of bainite formation is within 2--5 ℃s for the studied niobium steels and deformation is suitable for the occurrence of pearlite. The ferrite volume fraction increases with the increase of the austenite boundary area, and decreases with the increase of the cooling rate. The calculated CCT diagrams and the volume fraction of each phase are in good agreement with the measurements.

关键词： low carbon niobium steel thermodynamics supercooling degree continuous cooling transformation computer model

Thermodynamic Calculation of Carbide Precipitate in Niobium Microalloyed Steels

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Journal of Iron and Steel Research International 2006年第6期13卷 53-56页

作者： XU yun-bo yu yong-mei liu Xiang-hua WANG Guo-dong State Key Lab of Rolling and Automation Northeastern University Shenyang 110004 Liaoning China

On the basis of regular solution sublattice model, thermodynamic equilibrium of austenite/carbide in Fe-Nb-C ternary system was investigated. The equilibrium volume fraction, chemical driving force of carbide precipitates and molar fraction of niobium and carbon in solution at different temperatures were evaluated respectively. The volume fraction of precipitates increases, molar fraction of niobium dissolved in austenite decreases and molar fraction of carbon increases with decreasing the niobium content. The driving force increases with the decrease of temperature, and then comes to be stable at relatively low temperatures. The predicted ratio of carbon in precipitates is in good agreement with the measured one.

关键词： microalloyed steel thermodynamic calculation phase equilibrium carbide prediction model

Use of packed-fiber solid-phase extraction for sample clean-up and preconcentration of vitamin B_(12) before determination

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Chinese Chemical Letters 2009年第12期20卷 1491-1494页

作者： Fang Fang Xue Jun Kang Zhi yong liu yu Qin Ma Zhong Ze GU State Key Laboratory of Bioelectronics Southeast University Nanjing 210096 China

A rapid and simple preconcentration step applying packed-fiber solid-phase extraction columns has been investigated to vitamin B12. The extraction performance of the new method was investigated preliminarily on vitamin functional drink. The analysis used a reversed-phase C18 column, with a photo-diode array detector at 220 nm. The samples were preconcentrated with packed-fiber solid-phase extraction columns. Good linearity was observed in vitamin functional drink. The repeatability of extraction performance, expressed as relative standard deviations, was from 3.5% to 4.3%. The limit of detection （LOD） is 5 ng mL^-1 （S/N = 3）. Finally, the method had been applied for the determination of vitamin B12 in vitamin functional drink.

关键词： Vitamin B12 Nanofibers Packed-fiber solid-phase extraction Preconcentration

Effect of bilateral supraclavicular postoperative radiotherapy in middle and lower thoracic esophageal carcinoma

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World Journal of Gastroenterology 2014年第47期20卷 17970-17975页

作者： Yi Ren Chang Su Yang Zhou Xiang Zhao Cheng-Liang Yang yong-yu liu Department of Thoracic Surgery Liaoning Cancer Hospital and InstituteDalian Medical University Clinical Oncology College Department of Ultrasound Diagnosis People’s Hospital of Liaoning Province

AIM: To evaluate whether postoperative radiotherapy is an alternative to neck lymph node surgery and if it provides a survival benefit for those receiving two-field, chest and abdomen, lymphadenectomy.

关键词： Middle and lower thoracic esophageal carcinoma Lymph node metastasis Bilateral supraclavicular postoperative radiotherapy