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Cycle performance studies on a new HFC-161/125/143a mixture as an alternative refrigerant to R404

Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2012年第2期13卷 132-139页

作者： Xiao-hong HAN Yu QIU Ying-jie XU Men-yuan ZHAO qin WANG guang-ming CHEN State Key Laboratory of Clean Energy Utilization Institute of Refrigeration and CryogenicsZhejiang UniversityHangzhou 310027China

In this paper, a new ternary non-azeotropic mixture of HFC-161/125/143a （0.15/0.45/0.40 in mass fraction）, as a promising mixed refrigerant to R404A, is presented. The ozone depletion potential （ODP） of the new refrigerant is zero and its basic thermodynamic properties are similar to those of R404A, but its global warming potential （GWP） is much smaller than those of R507A and R404A. Meanwhile, theoretical calculations show that, under the working condition 1 （the average evaporation temperature： -23℃, the average condensing temperature： 43℃, the superheat temperature： 28℃, the subcooling temperature： 5 ℃）, the volumetric refrigerating effect and specific refrigerating effect of the new mixture are 2.33% and 15.48% higher, re- spectively, than those of R404A. The coefficient of performance （COP） of the new mixture is 5.19% higher than that of R404A and the pressure ratio of the new mixture is 0.82% lower than that of R404A. Equally, under the working condition II （the average evaporation temperature： -40℃, the average condensing temperature： 35℃, the superheating temperature： 30 ~C, the subcooling temperature： 5℃）, the volumetric refrigerating effect and specific refrigerating effect of the new mixture are 2.24% and 20.58% higher, respectively, than those of R404A. The COP of the new mixture is 4.60% higher than that of R404A and the pressure ratio of the new mixture is similar to that of R404A. The performances of the new mixture and R404A are compared in a vapor compressor refrigeration apparatus originally designed for R404A under several working conditions （condensing temperatures： 35-45℃, evaporation temperatures： -40--20℃）. Experimental results show that the new mixture can obtain a higher COP, by 6.3% to 12.1%, and a lower pressure ratio, by 1.8% to 6.6%, compared to R404A; although the discharge temperature of the new mixture is slightly higher than that of R404A. The advantages of the new mixture will be further verified in the actual system.

关键词： Alternative refrigerant Mixture Cycle nerformance. R404A HFC-161

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Anatomical and Chemical Alterations but not Photosynthetic Dynamics and Apoplastic Transport Changes are Involved in the Brittleness Culm Mutation of Rice

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Journal of Integrative Plant Biology 2008年第12期50卷 1508-1517页

作者： Zhuang-qin Duan Jun-Min Wang Lei Bai Zhi-guang Zhao Kun-Ming Chen Institute of Crop Sciences College of Agriculture and Biotechnology Zhejiang University Hangzhou 310029 China College of Life Sciences Lanzhou University Lanzhou 730000 China Institute of Crop and Nuclear Technology Utilization Zhejiang Academy of Agricultural Sciences Hangzhou 310029 China

Brittleness culm is an important agronomic trait that has a potential usefulness in agricultural activity as animal forage although the developmental mechanism is not clear yet. In the present study, the anatomical and chemical characteristics as well as some ecophysiological features in the brittleness culm mutation of rice （Oryza sativa L.） were investigated. Compared with the wild type （WT）, the brittleness culm mutant （bcm） exhibited higher culm vascular bundle distance and lower culm wall thickness, leaf interveinal distance and leaf thickness. Ratio of bundle sheath cell/whole bundle and areas of whole vascular bundles and bundle sheath of leaves were reduced while ratios of xylem and phloem to whole bundles were elevated in bcm. The Fourier transform infrared （FTIR） microspectroscopy analysis and further histochemical and physiological measurements revealed that the different contents and depositions of cell wall components such as pectins, lignin, suberin and cellulose all participated in the mutation of brittleness. However, the mutant presented no significant changes in leaf photosynthetic dynamics and apoplastic transport ability. These results strongly indicate that the alterations in anatomical and chemical characteristics, rather than changes in major ecophysiological features such as photosynthesis and apoplastic transport were involved in the brittleness mutation of rice.

关键词： anatomical and chemical characteristics apoplastic transport brittleness culm mutant photosynthetic dynamic rice.

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RESEARCH ON THE FLOATING OIL STORAGE SYSTEM FOR STRATEGIC PETROLEUM RESERVE

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Journal of Hydrodynamics 2004年第1期16卷 111-112页

作者： LIWen-long TanJia-hua qinShi-yuan LiRun-pei YangJian-min XuShou-qin XuXue-guang GongHui SchoolofNavalArchitectureandOceanEngineering ShanghaiJiaotongUniversityShanghai200030China ShanghaiJiaotongUniversity ShanghaiJiaotongUniversity Chairman MarineDesignandResearchInstituteofChina ShipbuildingTechnologyResearchInstitute MarineDesignandResearchInstituteofChina

The problem of petroleum safety is closely related to national politics andeconomics security and becomes one of key for discussion in China. The floating oil storage systemhas been proposed as a new facility for Strategic Petroleum Reserve (SPR) in our country. There aresome differences in solving this problem. Although many of domestic research institutions arestudying the project of SPR, the research is separate, and lack of comprehensive consideration, andfails to make a complete and scientific demonstration in many aspects, such as oil storage capacity,selection of storage sites, storage facilities, technologic and economic feasibility, riskassessment, etc. Therefore, no mature and systematic petroleum reserve theories have been formed upto now. Peoples argue the issue of objective of SPR, function, mode, cost, effect, etc. There arestill many bifurcations, so, it is necessary to make more detailed demonstration, and provide somescientific decision-making strategy for the governments. In this paper, several significant problemsare solved, for instance, the option of SPR facilities, the research on the principalcharacteristics of floating oil storage vessels, the a-nalysis of mooring system for oil storagevessels, the design of breakwater and the calculation of failure probability, the risk assessment offloating oil storage system, etc.

关键词： strategic petroleum reserve floating oil storage system mooring system hydrodynamic design risk assessment

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Captioning Videos Using Large-Scale Image Corpus

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Journal of Computer Science & Technology 2017年第3期32卷 480-493页

作者： Xiao-Yu Du Yang Yang Liu Yang Fu-Min Shen Zhi-guang qin Jin-Hui Tang School of Information and Software Engineering University of Electronic Science and Technology of China Chengdu 610054 China School of Software Engineering Chengdu University of Information Technology Chengdu 610225 China Center for Future Media University of Electronic Science and Technology of China Chengdu 611731 China School of Computer Science and Engineering University of Electronic Science and Technology of China Chengdu 611731 China Sichuan University West China Hospital of Stomatology Chengdu 610041 China School of Computer Science and Engineering Nanjing University of Science and Technology Nanjing 210094 China

Video captioning is the task of assigning complex high-level semantic descriptions （e.g., sentences or paragraphs） to video data. Different from previous video analysis techniques such as video annotation, video event detection and action recognition, video captioning is much closer to human cognition with smaller semantic gap. However, the scarcity of captioned video data severely limits the development of video captioning. In this paper, we propose a novel video captioning approach to describe videos by leveraging freely-available image corpus with abundant literal knowledge. There are two key aspects of our approach： 1） effective integration strategy bridging videos and images, and 2） high efficiency in handling ever-increasing training data. To achieve these goals, we adopt sophisticated visual hashing techniques to efficiently index and search large-scale images for relevant captions, which is of high extensibility to evolving data and the corresponding semantics. Extensive experimental results on various real-world visual datasets show the effectiveness of our approach with different hashing techniques, e.g., LSH （locality-sensitive hashing）, PCA-ITQ （principle component analysis iterative quantization） and supervised discrete hashing, as compared with the state-of-the-art methods. It is worth noting that the empirical computational cost of our approach is much lower than that of an existing method, i.e., it takes 1/256 of the memory requirement and 1/64 of the time cost of the method of Devlin et al.

关键词： video captioning hashing image captioning

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Synthesis and Characterization of Novel-4-Methyl-3-isoxazolidinone Derivatives

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Chemical Research in Chinese Universities 2006年第6期22卷 717-720页

作者： GAO Fei-fei ZHANG guang-liang ZHENG Liang-yu LI Yao-xian ZHANG Suo-qin College of Chemistry Ministry of Education Jilin University Changchun 130021 P. R. China Key Lab for Molecular Enzymology and Engineering Ministry of Education Jilin University Changchun 130021 P. R. China

A novel type of aeetohydrexyacid synthase inhibitors, 4-methyl-3-isoxazolidinone derivatives of sulfonylurea, was designed and synthesized. The structures of these compounds were confirmed by using MS, NMR, and elemen... 详细信息

关键词： 4-Methyl-3-isoxazolidinone Sulfonylureas Acetohydroxyacid synthase Herbicidal activity

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Effects of Mo on the Microstructure and Hydrogen Sorption Properties of Ti-Mo Getters

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Chinese Journal of Aeronautics 2007年第2期20卷 172-176页

作者： ZHOU Hong-guo WEI Xiu-ying MAO Chang-hui XIONG Yu-hua qin guang-rong Institute of the Advanced Electronic Materials Beijing General Research Institute for Non Ferrous Metal Beijing 100088 China

The effects of Mo on the microstructure evolution, porosity and hydrogen sorption properties of Ti-Mo getters are investigated in this work. The results show that the addition of Mo prolongs the densification process of Ti-Mo getters and results in a significant amount of sintered pores. With the Mo content increasing, the porosity of getters firstly increases reaching the maximum value as it attains about 7.5wt.%, and then drops. At the room temperature, the hydrogen sorption property of getters increases progressively with the Mo content increasing, but the tendency is not very clear before its content lies below 2.5wt.%. When the Mo content achieves about 7.5wt.%, the hydrogen sorption property proves to be the best. The discussion is made about the above mentioned phenomena inclusive of hydrogen sorption properties of getters under different activation conditions （from 500-750℃）.

关键词： Ti-Mo getter powder metallurgy microstructure hydrogen sorption property

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Wind-wave affected phosphate loading variations and their relationship to redox condition in Lake Taihu

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Science China Earth Sciences 2006年第z1期49卷 154-161页

作者： ZHANG Lu ZHU guangwei LUO Liancong GAO guang ZHANG Yunlin qin Boqiang FAN Chengxin Nanjing Institute of Geography&Limnology Chinese Academy of SciencesNanjing 210008China

Variation of wind speed and the physico-chemical parameters,such as dissolved phosphate,ferrous and manganese in lake water were observed on *** with the chemistry analysis and simulated experiment in lab,the change of phosphate concentration in lake water was *** variation of ferrous/phosphate ratio explained that along with the enhancement of wind-wave effect and the oxidation ability of lake water,the effects of co-precipitation and removal of dissolved phosphate and iron in the lake water were *** ferrous/phosphate ratio in pore water was less than 2.0,demonstrating that the dissolved phosphate can be released into the overlying ***,in the lake water,the stability of phosphate was controlled by the water *** phosphate release experiment showed that molecular release was only part of the whole and the direct discharge of phosphate in the pore water was also a *** mineralization and biological process of suspended particulates in the water may be another important reason for the whole phosphate loadings.

关键词： phosphate internal release redox condition ferrous/phosphate ratio Lake Taihu.

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Experimental research on unloading properties of clay under high stress

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Journal of China University of Mining and Technology 2008年第1期18卷 122-124页

作者： MA Jin-rong CUI guang-xin qin Yong ZHOU Guo-qing School of Architecture and Civil Engineering China University of Mining ＆ Technology Xuzhou.Jiangsu 221008 China School of Resources and Earth Science China University of Mining ＆ Technology Xuzhou.Jiangsu 221008 China State Key Laboratory for Geomechanics and Deep Underground Engineering China University of Mining ＆ Technology Xuzhou Jiangsu 221008 China

Abstract： Mechanical properties of clay under high stress are quite different from those under low stress. It is necessary to investi- gate unloading properties of clay under high stress for the design and construction of deep underground engineering projects. A series of experiments were conducted to investigate the unloading properties of clay under high confining pressures by using a SKA-1 high pressure consolidation instrument designed by us. The stress versus strain relationship and the way that K0 values of clay change during the loading-unloading process were discovered. The results show that there are clear differences in the state of stress and deformation behavior of the clay along different unloading paths.

关键词： high pressure Ko consolidation equipment clay value of Ko unloading property

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In-situ stress distribution and coalbed methane reservoir permeability in the Linxing area, eastern Ordos Basin, China

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Frontiers of Earth Science 2018年第3期12卷 545-554页

作者： Wei JU Jian SHEN Yong qin Shangzhi MENG Chao LI Guozhang LI guang YANG Key Laboratory of Coalbed Methane Resources and Reservoir Formation Process Ministry of Education China University of Mining and Technology Xuzhou 221008 China School of Resources and Geosciences China-University of Mining and Technology Xuzhou 221116 China China United Coalbed Methane Corporation Ltd. Beijing 100011 China

Understanding the distribution of in-situ stresses is extremely important in a wide range of fields such as oil and gas exploration and development, CO2 sequestration, borehole stability, and stress-related geohazards assessment. In the present study, the in-situ stress distribution in the Linxing area of eastern Ordos Basin, China, was analyzed based on well tested parameters. The maximum horizontal principal stress （SHmax）, minimum horizontal principal stress （Shmin）, and vertical stress （Sv） were calculated, and they were linearly correlated with burial depth. In general, two types of in-situ stress fields were determined in the Linxing area：（i） the in-situ stress state followed the relation Sv 〉 Snmax 〉 Shmin in shallow layers with burial depths of less than about 940 m, indicating a normal faulting stress regime; （ii） the Snmax magnitude increased conspicuously and was greater than the Sv magnitude in deep layers with depths more than about 940 m, and the in-situ stress state followed the relation Snmax 〉 Sv 〉 Shmin, demonstrating a strike-slip faulting stress regime. The horizontal differential stress （Snmax-Shmtn） increased with burial depth, indicating that wellbore instability may be a potentially significant problem when drilling deep vertical wells. The lateral stress coefficient ranged from 0.73 to 1.08 with an average of 0.93 in the Linxing area. The coalbed methane （CBM） reservoir permeability was also analyzed. No obvious exponential relationship was found between coal permeability and effective in-situ stress magnitude. Coal permeability was relatively high under a larger effective in-situ stress magnitude. Multiple factors, including fracture development, contribute to the variation of CBM reservoir permeability in the Linxing area of eastern Ordos Basin.

关键词： in-situ stress coalbed methane permeability lateral stress coefficient Linxing area Ordos Basin

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Effects of Lorentz Breaking on the Accretion onto a Schwarzschild-like Black Hole

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Communications in Theoretical Physics 2019年第5期71卷 568-572页

作者： Rong-Jia Yang He Gao Yao-guang Zheng qin Wu College of Physical Science and Technology Hebei UniversityBaoding071002China Hebei Key Lab of Optic-Electronic Information and Materials Hebei UniversityBaoding071002China National-Local Joint Engineering Laboratory of New Energy Photoelectric Devices Hebei UniversityBaoding071002China School of Information Engineering Guangdong Medical UniversityDongguan523808China

We formulate and solve the problem of spherically symmetric, steady state, adiabatic accretion onto a Schwarzschild-like black hole obtained recently. We derive the general analytic expressions for the critical points, the critical velocity, the critical speed of sound, and subsequently the mass accretion rate. The case for polytropic gas is discussed in detail. We find the parameter characterizing the breaking of Lorentz symmetry will slow down the mass accretion rate, while has no effect on the gas compression and the temperature profile below the critical radius and at the event horizon.

关键词： accretion mass accretion rate Lorentz breaking Schwarzschild-like black hole

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