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Stability Analysis of Distributed Parameter Systems on Temperature Measurement of Large-scale Objects

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Journal of Thermal Science 2007年第3期16卷 248-253页

作者： Zhenliang DING Li zhong feng YUAN Department of Electronic Engineering School of Automatic Measurement and Control Harbin Institute of Technology 150001 Harbin China

In this paper, the mechanical construction, thermal regulator design and temperature measurement system of a local area were set up for large-scale linear measurement. Numerical analysis based on temperature correlated characteristic is discussed to obtain optimal observation points for the measurements. The horizontal temperature distribution of the measured area is compared with the measurement of the variation of temperature at 15℃ and 20℃ over time, and characteristic of dynamic response is also discussed. In addition, the long-time stability of measured temperature is analyzed by means of using the standard deviation. It characterizes the temperature distribution performance of a large area and how it may impact the measurement of a large-scale object.

关键词： temperature control temperature measurement distribution parameter linear measurement.

Null Geodesics in Brane World Scenarios

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Communications in Theoretical Physics 2004年第1期41卷 48-50页

作者： ZHANGLi-feng ZHANGYuan-zhong InstituteofTheoreticalPhysics theChineseAcademyofSciencesP.O.Box2735Beijing100080China

We study the null bulk geodesic motion in the brane world in which the bulk metric has an un-stabilized extra spatial dimension. We find that the null bulk geodesic motion as observed on the 3-brane with Z2 symmetry would be a timelike geodesic motion even though there exists an extra non-gravitational force in contrast with the case of the stabilized extra spatial dimension. In other words the presence of the extra non-gravitational force would not violate the Z2 symmetry.

关键词： brane universe null geodesic

Fundamental Theories and Key Technologies for Smart andOptimal Manufacturing in the Process Industry

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Engineering 2017年第2期3卷 154-160页

作者： feng Qian Weimin zhong Wenli Du Key Laboratory of Aflvanced Control and Optimization for Chemical Processes Ministry of Education East China University of Science and TechnologyShanghai 200237 China

Given the significant requirements for transforming and promoting the process industry, we present themajor limitations of current petrochemical enterprises, including limitations in decision-making, produc-tion operation, efficiency and security, information integration, and so forth. To promote a vision of theprocess industry with efficient, green, and smart production, modern information technology should beutilized throughout the entire optimization process for production, management, and marketing. To focuson smart equipment in manufacturing processes, as well as on the adaptive intelligent optimization of themanufacturing process, operating mode, and supply chain management, we put forward several key scien-tific problems in engineering in a demand-driven and application-oriented manner, namely：intelligentsensing and integration of all process information, including production and management information; collaborative decision-making in the supply chain, industry chain, and value chain, driven by knowledge; cooperative control and optimization of plant-wide production processes via human-cyber-physical in-teraction; and Q life-cycle assessments for safety and environmental footprint monitoring, in addition totracing analysis and risk control. In order to solve these limitations and core scientific problems, we furtherpresent fundamental theories and key technologies for smart and optimal manufacturing in the processindustry. Although this paper discusses the process industry in China, the conclusions in this paper can beextended to the larocess industry around the world.

关键词： Process industry Smart and optimal manufacturing Green manufacturing High-end manufacturing Optimality assessment

EXPERIMENTAL STUDY OF CONDENSATION HEAT TRANSFER CHA- RACTERISTICS OF HORIZONTAL TUBE BUNDLES IN VACUUM STATES

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Journal of Hydrodynamics 2012年第4期24卷 628-634页

作者： CHENG Shen SUN feng-zhong SHI Yue-tao School of Energy Source and Power Engineering Shandong UniversityJinan 250061China

TO develop an excellent heat transfer element under the vacuum condition, experiments about the heat transfer performance of horizontal tube bundles of different materials under various vacuum conditions were carried out, including the stainless steel tube, the brass tube, the Ni-based implanted steel tube and the ion implanted brass tube. The relative trends show that the condensation heat transfer coefficient and the overall heat transfer coefficient of bundles of four materials all increase with the vacuum degree, especially, those of the Ni-based implanted steel tube and the ion implanted brass tube. Under a high vacuum condition （0.07 MPa）, the condensation heat transfer coefficient of the Ni-based implanted steel tube bundle is about 1.4 times of that of the stainless steel tube bundle, the condensation heat transfer coefficient of the ion implanted brass tube bundle is found to be about 1.3 times of that of the common brass tube bundle. Therefore, according to the condensation heat transfer characteristics studied under high vacuum conditions, it is believed that a dropwise condensation is partly achieved on the surface of these two implanted tube bundles, and the ion implantation is shown to be an effective method to achieve the dropwise condensation. Based on this study, it is believed that the Ni-based steel tube may replace the brass tube, which is more expensive as a heat transfer component.

关键词： vacuum heat transfer characteristics condensation heat transfer coefficient dropwise condensation

XML-based Data Processing in Network Supported Collaborative Design

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International Journal of Automation and computing 2010年第3期7卷 330-335页

作者： Qi Wang zhong-Wei Ren zhong-feng Guo School of Mechanical Engineering Shenyang University of Technology Shenyang 110870 PRC

In the course of network supported collaborative design, the data processing plays a very vital role. Much effort has been spent in this area, and many kinds of approaches have been proposed. Based on the correlative materials, this paper presents extensible markup language （XML） based strategy for several important problems of data processing in network supported collaborative design, such as the representation of standard for the exchange of product model data （STEP） with XML in the product information expression and the management of XML documents using relational database. The paper gives a detailed exposition on how to clarify the mapping between XML structure and the relationship database structure and how XML-QL queries can be translated into structured query language （SQL） queries. Finally, the structure of data processing system based on XML is presented.

关键词： Extensible markup language (XML) network supported collaborative design standard for the exchange of product model data (STEP) data analysis data processing relational database

Shape Setup System for 1700 Hot Strip Mill

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Journal of Iron and Steel Research International 2007年第5期14卷 27-30页

作者： GUO zhong-feng XU Jian-zhong LI Chang-sheng LIU Xiang-hua State Key Laboratory of Rolling and Automation Northeastern University Shenyang 110004 Liaoning China

Shape setup （SSU） system is the core technology for hot strip mill （HSM）. A precise SSU system was used to improve the strip quality for HSM. The function of SSU, setup, and feedback was introduced. The main mathematical models of roll gap profile and longitudinal strain difference are set up. Strip profile allocation strategy was researched according to the SSU system of a domestic 1 700 mm HSM. The SSU system was put into practical use and the measurement results showed that strip flatness variation and strip profile variation could be controlled in target scope.

关键词： SSU hot strip mill, shape strip profile flatness

Catalytic Asymmetric Mannich-Type Reaction Enabled by Efficient Dienolization of α,β-Unsaturated Pyrazoleamides

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Chinese Journal of Chemistry 2021年第1期39卷 55-61页

作者： Hai-Jun Zhang feng zhong Yan-Cheng Xie Liang Yin CAS Key Laboratory of Synthetic Chemistry of Natural Substances Center for Exellence in Moleculor SynthesisShanghai Istitute of Organic ChemistryUniversity of Chinese Academy of SciencesChinese Academy of Sciences345 Lingling RoadShanghai 200032China

(E)-α,β-Unsaturated pyrazoleamides undergo facile dienolization to furnish copper(I)-(1Z,3Z)-dienolates as the major in the presence of a copper(I)-(R)-DTBM-SEGPHOS catalyst and EtgN,which react with aldimines to afford syn-vinylogous products as the major dia-stereoisomers in high regio-and *** some cases,the diastereoselectivity is low,possibly due to the low ratio of copper(I)-(1Z,3Z)-dienolates to copper(I)-(1Z,3E)-dienolates.

关键词： Asymmetric catalysis Vinylogous reaction Pyrazoleamide Copper catalyst Dienolization

Magnetic reconnection structures in the boundary layer of an interplanetary magnetic cloud

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Science China(Technological Sciences) 2004年第1期47卷 6-14页

作者： WEI fengsi LIU Rui feng Xueshang zhong Dingkun YANG Fang Key Laboratory for Space Weather Chinese Academy of Sciences Beijing 100080 China Key Laboratory for Space Weather Chinese Academy of Sciences Beijing 100080 China Key Laboratory for Space Weather Chinese Academy of Sciences Beijing 100080 China Key Laboratory for Space Weather Chinese Academy of Sciences Beijing 100080 China Key Laboratory for Space Weather Chinese Academy of Sciences Beijing 100080 China

An interplanetary magnetic diffusion region was detected by WIND during 0735-0850 UT on May 15, 1997 when the front boundary layer of a magnetic cloud passed through the spacecraft about 190 earth radii upstream of the earth. The main signals of magnetic reconnection processes are: (i) Flow reversal was detected at about 0810 UT. The counter-streaming flows have the speeds of about 65 and 41 km/s, respectively, with an angle of about 140 degree between them. (ii) Hall magnetic field was detected. The Hall fields ?By and +By, perpendicular to the X-Z plane, with their magnitude up to ～7.0 nT, are superposed upon a guide field about 12 nT. (iii) Alfvenic fluctuations are obviously intensified inside the reconnection region; at the front boundary of the reconnection region, a slow-mode-like discontinuity was detected. (iv) Ions are heated intensively inside the reconnection region, with their temperature three times higher than that ahead of the boundary layer; electrons are also heated, with a little enhancement in their temperature. The above observations indicate that magnetic reconnection processes could take place in interplanetary space. Keywords solar wind - interplanetary magnetic clouds - magnetic reconnection

关键词： solar wind, interplanetary magnetic clouds, magnetic reconnection.

Synthesis and Optoelectronic Properties of Donor-acceptor Molecules Containing Pyromellitic Diimide Chromophore

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Chemical Research in Chinese Universities 2013年第6期29卷 1083-1088页

作者： ZHANG Qian LU Xue-feng WANG zhong-sheng ZHOU Gang Laboratory of Advanced Materials Department of ChemistryFudan University Shanghai 200438 P.R.China

Three donor-acceptor molecules containing pyromellitic diimide chromophore were designed and synthe- sized. The synthetic route towards the target compounds was systematically investigated and discussed in detail. The resulted organic semiconductors have shown promising optoelectronic properties as further revealed by UV-Vis ab- sorption spectroscopy, cyclic voltammetry, and theoretic calculation.

关键词： Pyromellitic diimide Donor-acceptor Charge transfer