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EIGEN-TEMPERATURE MODEL FOR THE ANNUAL AIR TEMPERATURE MOVEMENT EVALUATION AND FORECAST

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International Journal of Modeling, Simulation, and Scientific Computing 2013年第3期4卷 30-53页

作者： zong-chang YANG School of Information and Electronical Engineering Hunan University of Science and Technology Xiangtan 411201 P.R.China

Climate variability and its changes are issues of broader global *** study addresses the annual air temperature movement evaluation and forecasting based on principal component analysis(PCA).An Eigen-temperature model for describing the annual air temperature movement by employing PCA is *** for evaluation is generated by selecting principal orthogonal eigenvectors of covariance matrix of temperature *** principal eigenvectors are called“Eigen-temperatures”,since they are eigenvectors and each temperature movement is described by *** temperature movement is projected onto the subspace of eigenspace,and described by a linear combination of the ***,a forecast method for the temperature movement by employing the Eigen-temperatures is *** is implemented with polynomial curve fitting algorithm to estimate subsequent representation weights for the subsequent temperature movement with respect to the“Eigen-temperatures”generated by its previous temperature *** proposed Eigen-temperature model is applied to evaluation and forecasting for annual temperature movement at Tongchuan observation station of China from 1962 to 1971 and from 1994 to *** results agreeing well with actual observation values show workability of the *** analysis indicates its effectiveness that the proposed Eigen-temperature model is outperforming the classical AR model and the BP-ANN on the forecast tasks.

关键词： Principal component analysis annual air temperature movement Eigentemperature model.

Investigation of epididymal immunology

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Chinese Science Bulletin 2005年第18期50卷 1969-1974页

作者： chang zong-Liang Institute for Biochemistry and Cell Biology Chinese Academy of Sciences Shanghai 200031 China

Immunology is the study of the structure and function of the immune system. The immune system consists of an earlier-stage innate immunity and a later-stage adap-tive immunity. The task of the immune system is to efficiently respond to non-self antigens and the invasion of pathogens, thereby protecting the host’s homeostasis. This review article discusses the structure and function of the epididymis, in-cluding the composition of the epithelial cells of the epidi-dymis and their relationship to the immune system, through the assessment of alterations in the immune cells of the epididymis. The review also shows the anti-inflammatory properties of rat epididymal defensin and the description of the blood-epididymis barrier, immune barrier, epididymitis and pathological mechanisms of infertility in males. Taken together, we see that the epididymis possesses a close link with immunology. Finally, this review discusses the future of studies involving epididymal immunology.

关键词：附睾免疫系统炎症男性不育症抗原细胞

Study on Dynamic Characteristics of Hydraulic Pumping Unit on Offshore Platform

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China Ocean Engineering 2017年第6期31卷 693-699页

作者： chang zong-yu YU Yan-qun QI Yao-guang College of Engineering Ocean University of ChinaQingdao 266100China College of Mechanical and Electronic Engineering China University of PetroleumQingdao 266580China

A new technology of offshore oil rod pumping production is developed for offshore heavy oil recovery. A new type of miniature hydraulic pumping unit with long-stroke, low pumping speed and compact structure is designed based on the spatial characteristics of offshore platforms. By combining the strengths of sinusoidal velocity curve and trapezoidal velocity curve, a kinematical model of the acceleration, the velocity and displacement of the pumping unit＇s hanging point is established. The results show that the pumping unit has good kinematic characteristics of smooth motion and small dynamic load. The multi-degree-of-freedom dynamic model of the single-well pumping unit is established. The first and second order natural frequencies of the sucker rod string subsystem and the pumping unit subsystem are studied. The results show that the first and the second order natural frequencies among the pumping rod string, pumping unit-platform subsystem and the dynamic excitation have differences over 5 times from each other, indicating that resonance phenomenon will not appear during the operation and the dynamic requirements for field use are met in the system.

关键词： offshore platform platform pumping unit kinematic model dynamic model multiple degrees of freedom

Nanometer Stripe Microstructure of Supersaturated Solid Solution in Fe-Cu Alloy

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Journal of Iron and Steel Research International 2007年第1期14卷 64-68页

作者： REN Hui-ping WANG Hai-yan LIU zong-chang AN Zhi-guo College of Material and Metallurgy Engineering Inner Mongolia University of Science and TechnologyBaotou 014010 Inner Mongolia China

Strengthening due to precipitation of Cu in the a-Fe matrix is an important phenomenon utilized in the design of HSLA steels. In the present work, the microstructure of supersaturated solid solution in Fe-1.18%Cu binary alloy was investigated by means of high resolution electron microscopy. The results indicated that the solid solution was heterogeneous, there were lots of Cu atom clusters, which consisted of diffractive stripe microstructure similar to twin crystal. Orientation deviation was observed between two （110）o planes in diffractive stripes, which results in light and shade contrast. Furthermore, formation mechanisms of the nanometre stripe microstructure were discussed in terms of the interaction of Cu and Fe atoms in the Fe-Cu binary alloys.

关键词： Fe-Cu alloy supersaturated solid solution Cu-rich cluster nanometer stripe microstructure high resolution electron microscopy

Mechanism of Annealing Softening of Rolled or Forged Tool Steel

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Journal of Iron and Steel Research International 2003年第1期10卷 40-43页

作者： LIU zong-chang GAO Zhan-yong DONG Xue-dong DAI Jian-ming Baotou University of Iron and Steel Technology Fushun Special Steel Ltd Co

The steel specimens of nominal composition 0.3C-1.0Cr-1.0Mn-2.0Si-1.0Ni- 0.04 Nb were quenched and tempered or isothermally quenched from various temperatures. It is found that the steel quenched and tempered with a tensile strength of 1 500-1 600 MPa has a K ISCC (critical stress intensity factor) value below 15.0 MPa·m 1/2 . The steel isothermally quenched with a tensile strength of 1 350-1 750 MPa has a K ISCC value about 20.0 MPa·m 1/2 . In addition, with increase of isothermal quenching temperature, the tensile strength decreases greatly and K ISCC value does not pronouncedly change. The microstructure of isothermally quenched specimens is composed of bainite and retained austenite. The delayed fracture resistance is dependent on the stability of austenite, which is in turn related to the retained austenite volume fraction and carbon content in austenite.

关键词： high strength steel heat treatment mixed microstructure delayed fracture

Near-infrared dyes, nanomaterials and proteins

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Chinese Chemical Letters 2019年第10期30卷 1856-1882页

作者： zong chang Feng Liu Liang Wang Mengying Deng Chunhua Zhou Qinchao Sun Jun Chu Laboratory for Biomedical Optics and Molecular Imaging Institute of Biomedical and Health EngineeringShenzhen Institutes of Advanced TechnologyChinese Academy of SciencesShenzhen 518055China CAS Key Laboratory of Health Informatics Shenzhen Institute of Synthetic BiologyShenzhen-Hong Kong Institute of Brain ScienceShenzhen Institutes of Advanced TechnologyChinese Academy of SciencesShenzhen 518055China

Taking the advantage of reduced scattering and low autofluorescence background, the NIR fluorescence probes, such as fluorescence proteins, organic molecules and nanoparticles, not only hold the promise of in vivo imaging of biological processes in physiology and pathology with high signal-to-noise ratio, but also for clinical diagnosis. In this review, we provide an overview of the recent progress on NIR probes,focusing on fundamental mechanisms of NIR dyes and nanoparticles, and protein engineering strategies for NIR proteins.

关键词： Near-infrared II Small organic dye Nanoparticles Near-infrared fluorescent protein Bacteriophytochrome Fluorogen

Competency-based management effects on satisfaction of nurses and patients

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International Journal of Nursing Sciences 2014年第1期1卷 121-125页

作者： zong-Xia chang Gui-Hua Yang Wei Yuan Nursing Department People’s Hospital of Liaocheng CityLiaochengChina

Purpose:To evaluate the effect of competency-based management in improving nurse and patient ***:According to the competency-based management objectives and principles,821 nurses were classified into different levels based on clear nurse qualifications and post *** to the different levels of nursing staff and training plans with different emphases,the goal was for the nursing staff to gradually achieve the corresponding *** training programs for different levels of nurses were formulated to enable nurses to gradually increase their competency ***:After implementation of competency-based management,nurse job satisfaction and patient satisfaction increased significantly(P<0.01).Additionally,the reported nurse job burnout decreased(P<0.01).Conclusion:Competency-based management can promote nurses’enthusiasm,reduce job burnout,improve job satisfaction,as well as improve patient satisfaction.

关键词： Competency-based management Nurses Patient satisfaction

Sap Flow of Populus euphratica in a Desert Riparian Forest in an Extreme Arid Region During the Growing Season

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Journal of Integrative Plant Biology 2007年第4期49卷 425-436页

作者： Jian-Hua Si Qi Feng Xiao-You Zhang zong-Qiang chang Yong-Hong Su Hai-Yang Xi Cold and Arid Region Environmental and Engineering Research Institute the Chinese Academy of Sciences Alashan Desert Eco-hydrology Experimental Research Station Lanzhou 730000 China

In the present study, the heat pulse technique was applied to investigate the stem sap flow of Populus euphratica in a desert riparian forest in an extreme arid region from April to October 2003 and from May to October 2004. The experimental sites were in Qidaoqiao （101 °10′ E, 41°59′ N） and Bayantaolai farm （101°14′ E, 42°01′ N） in Ejina county, in the low reaches of the Heihe River, China. The results indicated that the diurnal change in the velocity of sap flow showed minor fluctuations. At night, the rising of sap flow could be observed in the main tree species because of root pressure. During the growing season, the maximum average velocity was observed in July, followed by August, and the same velocity was observed in September and May; the minimum velocity was observed in October. The transpiration from June to August during the growing season accounted for approximately 70% of the annual total transpiration. The sap flow velocity of P. euphratica trees of different ages could be arranged in the order： 15 yr 〉 25 yr 〉 50 yr. Sap flow velocity was closely related to changes in micrometeorological factors, with average sap flow velocity showing a significant linear correlation with net radiation, air temperature and relative humidity.

关键词： desert riparian forest extreme arid region heat-pulse technique Populus euphratica sap flow velocity.

A Study of the Characteristics of Microorganisms for Effective Degradation of Marine Oil Spills

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Petroleum Science 2006年第1期3卷 61-67页

作者： Zhang Zhongzhi Wei Xiaofang zong chang Yu Hongwen Li Chengjian He Ruibing Faculty of Chemistry ＆ Chemical Engineering China University of Petroleum Beijing 102249 China Bohai Oil Technical Service Company China National Offshore Oil Corp.Tanggu Hebei 065000 China

Four microorganism strains were isolated from coastal petroleum-polluted soil and sand samples of Bohai Sea oilfield; they were found to degrade marine oil spills effectively. The experimental results show that the degradation efficiency of crude oil with these four strains （XT-4, SZ-1-25, B-4-9, BS-3-12） is 95.97%, 96.01%, 97.99% and 98.99%, respectively, in their optimum conditions. The characteristics of bacterial biodegradation are investigated. The simulation biotreatment of oil-contaminated beach sand, with an initial oil content of 5,664mg/kg-dry-sand, shows that the residual oil content is 2,700 mg/kg-dry-sand and 2,679 mg/kg-dry-sand after 170 days＇ treatment with two bacteria （B-4-9, BS-3- 12）, respectively.

关键词： Petroleum pollution halophilic bacteria biodegradation simulation biotreatment of beach sand