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Effect of surfactant Tween on induction time of gas hydrate formation

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Journal of China University of Mining and Technology 2008年第1期18卷 18-21页

作者： ZHANG bao-yong WU Qiang SUN Deng-lin Safety Engineering College Heilongjiang Institute of Science and Technology Harbin Heilongjiang 150027 China CoUege of Resource and Environment Engineering Liaoning Technical University Fuxin Liaoning 123000 China

Acceleration of gas hydrate formation is important in preventing coal and gas outbursts and is based on a hydration mechanism. It becomes therefore necessary to investigate the effect of surfactants, acting as accelerants for hydrate formation, on induction time. We experimented with three types of a Tween solution with equal concentrations of 0.001 mol/L (T40, T40/T80 (1:1), T40/T80 (4:1)). by means of visual experimental equipment, developed by us, we measured generalized induction time using a Direct Observation Method. The experimental data were analyzed combined with a mass transfer model and a hydrate crystal nuclei growth model. Our major conclusions are as follows: 1) solubilization of surfactants produces supersaturated gas molecules, which promotes the mass transfer from a bulk phase to hydrates and provides the driving force for the complexation between host molecules (water) and guest molecules in a gas hydrate formation process; 2) when the solution of the surfactant concentration exceeds the critical micelle concentration (CMC), the surfactant in an aqueous solution will transform to micelles. Most of the gas molecules are bound to form clusters with water molecules, which promotes the formation of crystal nuclei of gas hydrates; 3) the surfactant T40 proved to have more notable effects on the promotion of crystal nuclei formation and on shortening the induction time, compared with T40/T80 (1:1) and T40/T80 (4:1).

关键词： gas hydrate surfactant induction time coal and gas outburst

Hardware/software partitioning based on dynamic combination of maximum entropy and chaos optimization algorithm

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Journal of Harbin Institute of Technology(New Series) 2010年第4期17卷 548-551页

作者：张宏烈张国印姚爱红 College of Computer science and Technology Harbin Engineering University College of Computer and Control Engineering Qiqihar University

This paper presents an algorithm that combines the chaos optimization algorithm with the maximum entropy ( COA-ME) by using entropy model based on chaos algorithm,in which the maximum entropy is used as the second method of searching the excellent solution. The search direction is improved by chaos optimization algorithm and realizes the selective acceptance of wrong solution. The experimental result shows that the presented algorithm can be used in the partitioning of hardware/software of reconfigurable system. It effectively reduces the local extremum problem,and search speed as well as performance of partitioning is improved.

关键词： hardware/software partitioning chaos optimization algorithm maximum entropy reconfigurable system

Spontaneous formation of single crystal ZnO nanohelices

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Chinese Physics b 2009年第4期18卷 1669-1673页

作者：武祥蔡伟曲凤玉 College of Chemistry and Chemical Engineering Harbin Normal University School of Materials science and Engineering Harbin Institute of Technology

This paper reports a novel helix-like ZnO nanostructure with several tens of nanometres in thickness synthesized on a gold-coated Si substrate by thermal evaporation of zinc sulfide powder at 1020℃. Transmission electron microscope characterization shows that as-synthesized ZnO nanohelices extend along [0111] direction and the axial direction of the helix is along [0001] direction. A catalyst-intervened dislocation-induced growth mechanism has been suggested to explain the formation of the helix-like ZnO nanostructures. This study opens a new route to construct helix-like ZnO nanostructures by different evaporation sources.

关键词： nanohelix thermal evaporation ZnO growth mechanism

Memory effect on the pressure-temperature condition and induction time of gas hydrate nucleation

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Journal of natural Gas Chemistry 2010年第4期19卷 446-451页

作者： Qiang Wu baoyong Zhang Safety Engineering College Heilongjiang Institute of Science and Technology Harbin 150027 Heilongjiang China

The focus of this study is to investigate the influence of memory effect and the relation of its existence with the dissociation temperature,using gas hydrate formation and dissociation *** is beneficial because memory effect is considered as an effective approach to promote the thermodynamic and dynamic conditions of gas hydrate *** experimental systems （twenty tests in total） were performed in a 1 L pressure *** types of hydrate morphology,namely massive,whiskery and jelly crystals were present in the *** pressures and temperatures at the time when visual hydrate crystals appeared were ***,the influence of memory effect was quantified in terms of pressure-temperature-time （p-T-t） *** results revealed that memory effect could promote the thermodynamic conditions and shorten the induction time when the dissociation temperature was not higher than 25℃.In this study,the nucleation superpressure and induction time decrease gradually with time of tests,when the earlier and the later tests are *** is assumed that the residual structure of hydrate dissociation,as the source of the memory effect,provides a site for mass transfer between host and guest ***,a driving force is created between the residual structures and its surrounding bulk phase to promote the hydrate ***,when the dissociation temperature was higher than 25 ℃,the memory effect *** findings provide references for the application of memory effect in hydrate-based technology.

关键词： gas hydrate memory effect nucleation thermodynamics induction time

Compensation Model for Shape Measuring of Cold Strip Rolling

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Journal of Iron and Steel Research International 2010年第6期17卷 21-26页

作者： YU bing-qiang SUN Ya-bo LIU Hong-min YOU Lei PENG Yan Engineering Research Center of Rolling Equipment and Complete Technology of Ministry of Education Yanshan University Qinhuangdao 066004 Hebei China

Some unavoidable factors in the process of cold strip shape measurement interfere with the shape meter, so the shape measuring results cannot reflect the true shape of the strip and the measuring precision is low. The influ- ences of the measuring error of the strip edges, the transverse temperature difference of the strip, the deflection of shape detection roller, and the shape of the strip coil on the shape measuring results were analyzed in detail, and the corresponding compensation models were established. The simulation calculation and analysis were carried out on a cold strip mill, and a number of disciplinarian cognitions were obtained.

关键词： cold strip rolling shape measuring compensation model

Feature Extraction and Dimensionality Reduction of Arc Sound under Typical Penetration Status in Metal Inert Gas Welding

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Chinese Journal of Mechanical Engineering 2012年第2期25卷 293-298页

作者： LIU Lijun LAN Hu ZHENG Hongyan JIAN Xiaoxia Ningbo Institute of Technology Zhejiang UniversityNingbo 315100China School of Material science ＆ Engineering Harbin University of Science and TechnologyHarbin 150080China Rongcheng College Harbin University of Science and TechnologyRongcheng 264300China

Arc sound is well known as the potential and available resource for monitoring and controlling of the weld penetration status,which is very important to the welding process quality control,so any attentions have been paid to the relationships between the arc sound and welding *** non-linear mapping models correlating the arc sound to welding parameters have been established with the help of neural ***,the research of utilizing arc sound to monitor and diagnose welding process is still in its infancy.A self-made real-time sensing system is applied to make a study of arc sound under typical penetration status,including partial penetration,unstable penetration,full penetration and excessive penetration,in metal inert-gas（MIG） flat tailored welding with spray *** sound is pretreated by using wavelet de-noising and short-time windowing technologies,and its characteristics,characterizing weld penetration status,of time-domain,frequency-domain,cepstrum-domain and geometric-domain are ***,high-dimensional eigenvector is constructed and feature-level parameters are successfully fused utilizing the concept of primary principal component analysis（PCA）.Ultimately,60-demensional eigenvector is replaced by the synthesis of 8-demensional vector,which achieves compression for feature space and provides technical supports for pattern classification of typical penetration status with the help of arc sound in MIG welding in the future.

关键词： metal inert gas welding penetration arc sound feature extraction dimensionality reduction

Establishment Method of Shape Standard Curve based on Stepwise Optimization and Its Compensation Models

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Chinese Journal of Mechanical Engineering 2011年第1期24卷 105-112页

作者： SUN Yabo LIU Hongmin PENG Yan Engineering Research Center of Rolling Equipment and Complete Technology of Ministry of Education Yanshan University Qinhuangdao 066004 China State Key Laboratory of Metastable Materials science ＆ Technology Yanshan University Qinhuangdao 066004 China

There are very few researches on the shape standard curve currently,and they merely remain on the level of description of the general concept and production experiences,lacking of the in-depth theoretical analysis,and the concrete principle,method and steps for determining the shape standard curve are not put forward,therefore,they are not applicable in industrial *** is the weakest spot in the research on the basic shape *** this paper,the basic shape standard curve and the transverse distribution curve of the exit thickness are attained with stepwise optimization,which is based on the theoretical calculation method of the shape standard curve of strip mills proposed by *** calculating the shape discrimination model and the shape forecast model separately,the simultaneous iterative calculation by the previous method is avoided,and the speed and stability of calculation are *** compensation models of the transverse temperature difference of the strip,the shape detection roller deflection and the shape of the strip coil are established,respectively,meantime,the basic shape standard curves are compensated,and the relatively perfect theoretical establishment method of the shape standard curve is *** simulation and calculation are done on a 1 220 mm five-stand cold strip tandem *** simulation and calculation result shows that the principle,method and steps for determining the shape standard curve are correct and feasible,and the correctness of theoretical analysis and calculation is *** paper proposes an idea and a method for the establishment of the shape standard curve in the rolling processes of cold strip mills,which develop the theory and model of the shape standard curve and improve the quality and efficiency of the shape control in the rolling processes of cold strip mills.

关键词： strip rolling shape crown shape standard curve stepwise optimization compensation model

Development of an electrochemical immunoassay for detection of gatifloxacin in swine urine

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Journal of Zhejiang University-science b(biomedicine & biotechnology) 2012年第2期13卷 118-125页

作者： Jian YI Meng MENG Zhong-qiu LIU Jin-fang ZHI Yuan-yang ZHANG Jing XU Ya-bin WANG Jin-ting LIU Ri-mo XI School of Chemistry and Chemical Engineering Shandong UniversityJinan 250100China College of Pharmacy and Tianjin Key Laboratory of Molecular Drug Research Nankai UniversityTianjin 300071China Technical Institute of Physics and Chemistry Chinese Academy of SciencesBeijing 100080China

To detect gatifloxacin （GAT） residue in swine urine, an electrochemical immunoassay was established, An indirect competitive immunoassay was developed, in which the coating antigen is immobilized in an enzyme-linked immunosorbent assay （ELISA） plate and GAT residue from the sample competes with the limited binding sites in added anti-GAT antibody. Horseradish peroxidase （HRP） conjugated to goat anti-rabbit IgG was used as the enzymatic label. A carbon fiber working electrode was constructed and current signals were detected by using hydrogen peroxide as a substrate and hydroquinone as an electrochemical mediator. The electrochemical immunoassay was evaluated by analysis of GAT in buffer or swine urine and an average value of half inhibition concentration （IC50） of 8.9 ng/ml was obtained. Excellent specificity of the antibody was achieved with little cross-reaction with Iomefloxacin （3.0%）, ciprofloxacin （3.0%）, and ofloxacin （1.9%） among commonly used （fluoro）quinolones. In conclusion, the im- munoassay system developed in this research can be used as a rapid, powerful and on-site analytical tool to detect GAT residue in foods and food products.

关键词： Gatifloxacin Drug residue Antibody Carbon fiber electrode Electrochemical immunoassay

A Modified Method for the Development of SSR Molecular Markers based on Redundant EST Data and Its Application in Soybean

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Journal of Integrative Agriculture 2012年第4期11卷 545-555页

作者： ZHAO Xue CHANG Wei HAN Ying-peng TENG Wei-li LI Wen-bin Key Laboratory of Soybean biology Ministry of Education/Soybean Research InstituteNortheast Agricultural UniversityHarbin 150030P.R.China

EST-derived SSR marker has been developed in many species,but few methods of high efficiency have been reported for the exploitation of EST-SSR ***,a high efficiency method for mining millions of redundant EST data is needed.A modified method for the EST-SSR development with high efficiency was established based on the redundant EST data of soybean in this *** method achieved its function through classifying ESTs according to the same SSR motif and detected candidate loci with redundant *** this study,a total of 80 polymorphic EST-SSR markers of soybean were developed,50 of them were exploited by this modified method which proved the higher speed and efficiency of this *** the 80 polymorphic EST-SSRs were mapped on soybean physical map through in silico mapping and 15 markers were integrated on a genetic map constructed in previous study.A software named hpSSR（high polymorphic SSR） was programmed based on the concept of the up-built method for EST-SSR *** method is not only pragmatic for EST-SSR exploitation in soybean,but also effective for the development of the marker in other species if the redundancy EST data is available.

关键词： EST-SSR soybean polymorphism genetic mapping in silico mapping