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Research on Oxygen Sensor for Metallurgical Process

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Journal of Iron and Steel Research International 2001年第1期8卷 60-62页

作者： kong Xiang-hua WANG Xiao-feng LIU Qing-guo University of Science and Technology beijing

A new technique for manufacture of the oxygen sensor used for metallurgical process has been *** powder of MgO-PSZ was prepared by *** MgOPSZ tube was prepared by powder injection molding(PIM).The final sintered tube was assembled into oxygen cell,then tested in laboratory and on RH *** results showed that the thermal shock resistance of MgO-PSZ matrix is strong enough for determining the active oxygen concentration in steel *** reproducibility of the EMF measurement is very *** structure of the tube has been analysed by means of SEM and *** addition,the characteristics such as the density and phase ratio in the product were compared with that of Shijiazhuang Maple Wood Sensor Company s product.

关键词： MgO-PSZ oxygen sensor powder injection molding solid electrolyte

Hydroformylation of Oleyl Alcohol Catalyzed by Rh-OPGPP Complex

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Chinese Chemical Letters 2002年第6期13卷 497-498页

作者： Fan Zhi kong Yan hua WANG Zi Lin JIN State Key Laboratory of Fine Chemicals Dalian University of TechnologyDalian 116012

Polyether-tailored phosphite modified rhodium complex formed in situ was highly active in the hydroformylation of oleyl alcohol in nonaqueous phosphite/heptane system where the phosphite acted both as the ligand and the second phase. This catalyst was easily separated by simple decantation and can be used for five times with only a slight decrease in activity.

关键词： Phosphite hydroformylation oleyl alcohol nonaqueous biphasic catalysis.

Colossal switchable photocurrents in topological Janus transition metal dichalcogenides

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npj Computational Materials 2021年第1期7卷 284-292页

作者： Haowei Xu hua Wang Jian Zhou Yunfan Guo Jing kong Ju Li Department of Nuclear Science and Engineering Massachusetts Institute of TechnologyCambridgeMAUSA Department of Electrical Engineering and Computer Science Massachusetts Institute of TechnologyCambridgeMAUSA Department of Materials Science and Engineering Massachusetts Institute of TechnologyCambridgeMAUSA

Nonlinear optical properties,such as bulk photovoltaic effects,possess great potential in energy harvesting,photodetection,rectification,*** enable efficient light–current conversion,materials with strong photo-responsivity are highly *** this work,we predict that monolayer Janus transition metal dichalcogenides(JTMDs)in the 1T′phase possess colossal nonlinear photoconductivity owing to their topological band mixing,strong inversion symmetry breaking,and small electronic bandgap.1T′JTMDs have inverted bandgaps on the order of 10 meV and are exceptionally responsive to light in the terahertz(THz)*** first-principles calculations,we reveal that 1T′JTMDs possess shift current(SC)conductivity as large as 2300 nmμA V^(−2),equivalent to a photo-responsivity of 2800 mA/*** circular current(CC)conductivity of 1T′JTMDs is as large as∼104 nmμA V^(−2).These remarkable photo-responsivities indicate that the 1T′JTMDs can serve as efficient photodetectors in the THz *** also find that external stimuli such as the in-plane strain and out-of-plane electric field can induce topological phase transitions in 1T′JTMDs and that the SC can abruptly flip their *** abrupt change of the nonlinear photocurrent can be used to characterize the topological transition and has potential applications in 2D optomechanics and nonlinear optoelectronics.

关键词： topological transition nonlinear

Precipitation behavior of P550 steel for non-magnetic drill collars during isothermal aging at 650–900℃

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Journal of Iron and Steel Research International 2022年第4期29卷 636-646页

作者： Li-wei Xu huai-bei Zheng hua-bing Li Zhou-hua Jiang Shu-cai Zhang Jiang-tao Yu Hao Feng Yue Lin School of Metallurgy Northeastern UniversityShenyang 110819LiaoningChina State Key Laboratory of Metal Material for Marine Equipment and Application Anshan 114002LiaoningChina

Precipitation behavior of P550 steel for non-magnetic drill collars was investigated by microstructure characterization as well as thermodynamic *** results demonstrate that the main precipitate formed at 650–900℃was cellular Cr_(2)N,and its precipitation depended heavily on the aging *** most sensitive precipitation temperature of cellular Cr_(2)N was 750℃.At 750℃,the cellular Cr_(2)N exhibited fast-slow precipitation kinetics with the aging time *** initial precipitation of cellular Cr_(2)N was governed by the short-range intergranular diffusion of *** long-term aging,its growth was controlled by the long-range bulk diffusion of *** addition,cellular Cr_(2)N induced the precipitation of r phase ahead of the cell after long period of *** the nitrogen content resulted in the increment of both the nucleation site and the driving force for the cellular Cr_(2)N,which jointly promoted its precipitation.

关键词： P550 steel Non-magnetic drill collar Precipitation behavior Cellular Cr_(2)N r Phase Nitrogen

SPATIAL GRADIENT ANALYSIS OF URBAN GREEN SPACES COMBINED WITH LANDSCAPE METRICS IN JINAN CITY OF CHINA

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Chinese Geographical Science 2005年第3期15卷 254-261页

作者： kong Fan-hua Nobukazu NAKAGOSHI YIN Hai-wei Akira KIKUCHI Graduate School for International Development and Cooperation Hiroshima University Higashi-Hiroshima 739-8529 Japan Department of Urban and Resources Sciences Nanjing University Nanjing 210093 P. R. China

Urban green spaces have been arisen growing concern responded to the social and environmental costs of urban sprawl. A wide range of planning and policies has been and/or will be designed to protect urban green spaces and optimize their spatial pattern. A better design or planning of urban green space can make a major contribution to quality of environment and urban life, and furthermore can decide whether we can have a sustainable development in the urban area. Information about the status quo of urban green spaces can help planners design more effectively. However, how to quantify and capture such information will be the essential question we face. In this paper, to quantify the urban green space, a new method comprising gradient analysis, landscape metrics and GIS was developed through a case of Jinan City. The results demonstrate: 1) the gradient analysis is a valid and reliable instrument to quantify the urban green space spatial pattern precisely; 2) using moving window, explicit landscape metrics were spatially realized. Compared with quantifying metrics in the entire landscape, it would be better to link pattern with process and establish an important basis for analyzing the ecological and socioeconomic functions of green spaces.

关键词： urban green space spatial pattern gradient analysis landscape metrics GIS Jinan City

Drag derived altitude aided navigation method

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Chinese Journal of Aeronautics 2017年第5期30卷 1750-1764页

作者： hua SONG Meiling WANG Jing YANG Dantong SUN Longtao kong Chunling WEI School of Automation Science and Electrical Engineering Beihang University Beijing 100083 China Collaborative Innovation Center of Advanced Aero-Engine Beihang University Beijing 100083 China National Key Laboratory of Space Intelligent Control Technology Beijing 100094 China

The navigation problem of the lifting reentry vehicles has attracted much research interest in the past decade. This paper researches the navigation in the blackout zone during the reentry phase of the aircraft, when the communication signals are attenuated and even interrupted by the blackout zone. However, when calculating altitude, a pure classic inertial navigation algorithm appears imprecise and divergent. In order to obtain a more precise aircraft altitude, this paper applies an integrated navigation method based on inertial navigation algorithms, which uses drag derived altitude to aid the inertial navigation during the blackout zone. This method can overcome the shortcomings of the inertial navigation system and improve the navigation accuracy. To further improve the navigation accuracy, the applicable condition and the main error factors, such as the atmospheric coefficient error and drag coefficient error are analyzed in detail. Then the damping circuit design of the navigation control system and the damping coefficients determination is introduced. The feasibility of the method is verified by the typical reentry trajectory simulation, and the influence of the iterative times on the accuracy is analyzed. Simulation results show that iterative three times achieves the best effect.

关键词： Aided navigation system Blackout zone Drag derived altitude Inertial navigation Integrated navigation Reentry vehicles

A study of suspended sediment concentration in Yangshan deep-water port in Shanghai,China

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International Journal of Sediment Research 2012年第1期27卷 50-60页

作者： Shu-hua ZUO Ning-chuan ZHANG bei LI Shen-liang CHEN Key Laboratory of Engineering Sediment of Ministry of Communications Tianjin Research Institute of Water Transport Engineering State Key Laboratory of Coastal and Offshore Engineering Dalian University of Technology State Key Laboratory of Estuarine and Coastal Research East China Normal University

Suspended sediment concentration(SSC) plays an important role in the estuarine *** spatial or temporal variations in coastal zones and estuaries indicate that sediments are suspended, transported and deposited under various actions,such as the river discharge,waves,currents and local *** deep-water port is located in the Qiqu Archipelago with many islands and tidal *** Yangshan deep-water port sea area as an example,an analysis of distributions and variations in the SSC based on data measured in Oct.1996,Jan.1999,May 2006 and May 2007 and the surface SSC data measured during the period from 1998 to 2008,has been *** from the study suggest that:(1) the yearly-averaged SSC decreased from 1998 to 2008;(2) the SSC has strong seasonal variations,the monthly-averaged SSC values are higher from November to April of the next year(the winter half year) than from May to October(the summer half year);(3) the periodic nature of the changes are obvious,which is consistent with a tidal semimonthly cycle of approximately 14.8 days;(4) the vertical distribution which is an e exponential distribution increase from the surface to the ***,the data indicate that tidal currents are the most dominant factor affecting the *** the Yangtze River discharges abundant sediments to the study area,it does not directly affect concentration variations in seasonal time *** in yearly variation or long time scales,the SSC varying trend is coincident with sediment discharge change of the Yangtze *** addition,the construction projects,or dumping of sediments,have obvious effects on SSC and sedimentation for part of the area."Strait-channel effects" have some degree of influence to the SSC distribution around islands.

关键词： Yangshan deep-water port Hydrodynamic Suspended sediment concentration(SSC) Strait-channel effects

Transmission capacity maximization for LED array-assisted multiuser VLC systems

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Science China(Information Sciences) 2015年第8期58卷 117-130页

作者： kong Lei SHEN Hong XU Wei ZHANG hua ZHAO ChunMing YOU XiaoHu National Mobile Communications Research Laboratory Southeast University

In this paper, we present a light-emitting diode(LED) array-assisted visible light communication(VLC) system. Considering the requirements of illumination, the human eye safety, and the energy saving,we optimize the optical power allocation(PA) to maximize the transmission capacity of the overall ***, we discuss two typical scenarios where the LED array in each room serves multiple users either simultaneously or in a round-robin manner. The problem corresponding to the first case turns out to be nonconvex whose globally optimal solution is hard to obtain. To address this difficult problem, we first adopt the famous gradient projection algorithm to obtain a locally optimal solution, then we employ powerful convex relaxation techniques, and achieve a high-quality solution. While for the round-robin case, we are able to derive an optimal solution in closed form by virtue of Karush-Kuhn-Tucker conditions. Interestingly, the derived closedform solution follows a water-filling pattern with both square root and two-side clipping operations, which differs from the conventional water-filling-like PA in radiofrequency channels. Numerical results depict the performance advantage provided by the proposed PA strategies under various settings.

关键词： light-emitting diodes visible light communication power allocation multiuser transmission convex relaxation

Removal of Methylene Blue with Hemicellulose/Clay Hybrid Hydrogels

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Chinese Journal of Polymer Science 2016年第6期34卷 709-719页

作者： He-li Cheng Qing-hua Feng Chuan-an Liao Yu Liu Dong-bei Wu 王启刚 Department of Chemistry Tongji University Institute of Pulp and Papermaking Hubei University of Technology Pharmaceutical College Guangxi Medical University Key Laboratory of Pulp and Paper Science & Technology of Ministry of Education of China Qilu University of Technology

In this study, we chose corn stover hemicellulose for the preparation of hydrogels with admirable adsorption properties under mild alkaline conditions. Clay nanosheets were introduced to this system and hemicellulose/clay hybrid hydrogels were prepared. Morphological, mechanical properties and the methylene blue adsorption behaviors of the prepared hydrogels were studied. Results suggested that the addition of clay not only improved the mechanical strength of hemicellulose-based hydrogels, but also increased the adsorption capacity on methylene blue. Moreover, the adsorptions were confirmed to follow pseudo-second order equation for both gels with and without clay. The maximum adsorption capacities on methylene blue for hemicellulose-based hydrogels with or without clay reached 148.8 and 95.6 mg/g, respectively. These results implied that hemicellulose-based hydrogels could be used as promising adsorbents for the removal of methylene blue from waste water.

关键词： Hemicellulose Hybrid hydrogel Clay Adsorption.