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New Solution to Surface Temperature of Casting Slab Measurement Based on Preceded Reflector and Multi-Wavelength

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Journal of Iron and Steel research International 2012年第8期19卷 12-16页

作者： LIU Jun1, MA Jiao-cheng2. YANG Feng3, XIAO Hui1, RAO Li-min1 (1. School of Nuclear Engineering and Technology, East China institute of Technology, Fuzhou 344000, Jiangxi, China 2. School of Mechanical Engineering and Automation, Northeastern university, Shenyang 110004, Liaoning, China 3. School of Civil and {2. Engineering, East China institute of Technology, Fuzhou 344000, Jiangxi, China) [a] School of Nuclear Engineering and Technology East China Institute of Technology Fuzhou 344000 Jiangxi China [b] School of Mechanical Engineering and Automation Northeastern University Shenyang 110004 Liaoning China [c] School of Civil and environmental Engineering East China Institute of Technology Fuzhou 344000 Jiangxi China

The surface temperature of casting slab is an important parameter in the metallurgy field. Because the surface emissivity is uncertain and also unknown, it is difficult to measure the slab surface temperature accurately. A method based on preceded reflector and multi-wavelength was put forward to deal with the difficulty in surface temperature measurement of casting slab. On the premise of preceded reflector and non-preceded reflector, the method establishes the radiation energy equations and works out the emissivity and temperature in the equations. Also, the multilayer modeling of casting slab surface and multiple reflection-absorption process modeling were built by Monte Carlo method. The temperature measuring method had been applied in the continuous casting field. In order to verify the measured result, the thermal imaging method was adopted when the slab surface emissivity was set by repeated tests. Finally, the measured and verified temperature curves keep a same tendency and the error of the values is lower than 5℃. The comparison result shows that the method can measure temperature accurately.

关键词： casting slab emissivity surface temperature preceded reflector multi-wavelength

3D mathematical model for suspended load transport by turbulent flows and its applications

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Science China(Technological Sciences) 2004年第2期47卷 237-256页

作者： LU Yongjun1,DOU Guoren1,HAN Longxi2.SHAO Xuejun3 & YANG Xianghua1,3 1.Nanjing Hydraulic research institute,Nanjing 2.002.,China 2.College of {2. Engineering of Hohai university,Nanjing 2.0098,China 3.Department of Hydraulic Engineering,Tsinghua university,Beijing 100084,China 1. Nanjing Hydraulic research institute 210029 Nanjing China 2. College of environmental Engineering of Hohai university 210098 Nanjing China 3. Department of Hydraulic Engineering Tsinghua University 100084 Beijing China

This paper presents a 3D mathematical model for suspended load transport in turbulent flows. Based on Dous stochastic theory of turbulent flow, numerical schemes of Reynolds stresses for anisotropic turbulent flows were obtained. A refined wall function was employed to treat solid wall boundaries. The equations for 2. suspended load motion and sorting of bed material have been expanded into 3D cases. Numerical results are validated by the measured data of the Gezhouba Project, and proved to be in good agreement with the experimental. The present method has been employed to simulate sediment erosion and deposition in the dam area of Three Gorges Project, and for the operation of the project, siltation process and deposition pattern in the near-dam area of the reservoir, size distribution of the deposits and bed material, and flow fields and sediment concentration fields at different time and elevations are predicted. The predicted results are close to the experimental observations in physical model studies. Thus, a new method is established for 3D simulation of sediment motion in dam areas of multi-purpose water projects.

关键词： turbulent flows, Dou's stochastic theory, nonuniform suspended load, riverbed erosion and deposition, 3D mathematical model, Three Gorges Project.

Morphological Evolution of Nb_2._5 in a Solvothermal Reaction: From Nb_2._5 Grains to Nb_2._5 Nanorods and Hexagonal Nb_2._5 Nanoplatelets

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Journal of Wuhan university of Technology(Materials Science) 2009年第2期24卷 245-248页

作者：胡卫兵 School of Chemical and environmental Engineering Hubei Institute for Nationalities Department of Physics Huazhong University of Science and Technology

Novel Nb2.5 nanorods and polygonal Nb2.5 platelets were generated by a simple solvothermal technique. The geometry evolution of the resultant Nb2.5 from amorphous nanoparticles to crystallized particles, from polygonal platelets to well-elongated nanorods was been studied in detail. The processing parameters, including the reaction temperature, reaction time, concentration of the precursors, and pH value of the solution, which affect the shape and size of the nanorods, were investigated. The Nb2.5 nanorods with different aspect ratios were examined by XRD, SEM and TEM. The experimental results show that Nb2.5 nanorod is the orthorhombic structure and well-crystallized. The growth of the nanorods follows their [001] direction. The successful generation of high quality Nb2.5 nanorods is not only important for transition metal oxide research, but also potentially important for further formation of new Nb-based 1-D nanostructures, such as NbS2.and NbN.

关键词： solvothermal morphological evolution Nb2.5 nanomateraials

“Tali Glaciation” on Massif Diancang

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Science China Earth Sciences 2007年第11期50卷 1685-1692页

作者： YANG JianQiang1, CUI ZhiJiu2. YI ChaoLu1, SUN JiMin3 & YANG LiRong3 1 institute of Tibetan Plateau research, Chinese Academy of Sciences, Beijing 100085, China 2.College of {2. Sciences, Peking university, Beijing 100871, China 3 institute of Geology and Geophysics, Chinese Academy of Sciences, Beijing 10002., China 1. institute of Tibetan Plateau research Chinese Academy of Sciences Beijing 100085 China 2. College of environmental Sciences Peking University Beijing 100871 China 3. institute of Geology and Geophysics Chinese Academy of Sciences Beijing 100029 China

The term of ''Tali Glaciation'' is nominated from Massif Diancang in Yunnan Province. The confusing process of the term''s being put forward is confirmed through literature checking. Based on several times of field trip, the glacial landforms in this region are studied in detail, and the magnitude of the glaciation was determined. According to the numerical ages from TL, AIMS ^(14)C and OSL dating, the earliest glacial advance on Massif Diancang occurred at 30—40 ka BP, followed by the advances at the last stage of the last glaciation, the late glacial and neoglations in turn, until glaciers vanished at 1.2.1.5 ca. a BP in this region. It can be concluded that glaciers were limited above 3600 m a.s.l., and no glaciers existed on the lower part and adjacent mountains since the last glaciation.

关键词： Massif Diancang,Tali Glaciation,glacial landform,glaciation sequence,numerical dating

Experimental Study of Sediment Incipience Under Complex Flows

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Transactions of Tianjin university 2008年第4期14卷 300-306页

作者： LIU Chunrong DENG Liying HUANG Zhenhua HUHE Aode Maritime research Center School of Civil and Environmental Engineering Nanyang Technological University Singapore 639798 College of Mechanics and Aerospace Hunan University Changsha 410082 China School of Civil and environmental Engineering Nanyang Technological University Singapore 639798 institute of Mechanics Chinese Academy of Sciences Beijing 100080 China

Sediment incipience under flows passing a backward-facing step was studied. A series of experiments were conducted to measure scouring depth, probability of sediment incipience, and instantaneous flow velocity field downstream of a backward-facing step. Instantaneous flow velocity fields were measured by using Particle Image Velocimetry (PIV), and an image processing method for determining probability of sediment incipience was employed to analyze the experimental data. The experimental results showed that the probability of sediment incipience was the highest near the reattachment point, even though the near-wall instantaneous flow velocity and the Reynolds stress were both much higher further downstream of the backward-facing step. The possible me- chanisms are discussed for the sediment incipience near the reattachment point.

关键词： sediment transport local scour complex flows particle image velocimetry sediment incipience

environmental archaeology of the Dachang region in the Daning Valley,the Three Gorges reservoir region of the Yangtze River,China

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Chinese Science Bulletin 2008年第S1期53卷 140-152页

作者： ZHANG Yun 1 &ZHU Cheng 2.1 State Key Laboratory of Vegetation and environmental Change,institute of Botany,Chinese Academy of Sciences,Beijing 100093, China 2.School of Geographic and Oceanographic Sciences,Nanjing {2.,Nanjing 2.0093,China 1. State Key Laboratory of Vegetation and environmental Change Institute of Botany Chinese Academy of Sciences Beijing 100093 China 2. School of Geographic and Oceanographic Sciences Nanjing University Nanjing 210093 China

environmental archaeology of archaeological sites on both sides of the Dachang section in the Daning River,the Three Gorges of the Yangtze River,shows that riverbed evolution has a great influence on the distribution of archaeological sites during the prehistorical and historical period,and it restricts human activity and the development of ancient *** investigation,dating data,paleocurrent analysis of 100 gravels on the riverbed and archaeological excavation reveal that the riverbed of the Dachang section developed in the Shuangyantang region during the early stage,after about 30 kaBP it shifted westward gradually and reached the present *** with the westward shift,the focus of ancient culture changed for several *** the Western Zhou Dynasty's period,the east riverbank of the Daning River was the main residential *** the Han Dynasty,along with the westward shift,the living space of ancient people was no longer confined to the east riverbank and the focus of culture moved *** the Zhangjiawan site became the main dwelling *** the late Han Dynasty, the villages were flooded and the ancients had to immigrate to a high *** of the Han and the Jin Dynasties outcropped on the flood plain of the east bank because their surface sediments were eroded by several flood events and the westward shift of the riverbed.

关键词： the Daning River environmental archaeology the Shuangyantang site the Zhangjiawan site tombs of the Han and the Jin Dynasties

The Isotope Geochemistry of N2. in Natural Gas Pools

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沉积学报 1999年第2期 153-159页

作者： ZHU Yue nian 1 SHI Bu qing 1 FANG Chao bin 2. 1 ( institute of Petroleum Resources & environmental Geology,Petroleum {2., Dongying 2.7062.Shandong,China) 2.(Exploration & Development Scientific research institute,China Offshore Oil Nanh

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ＩＮＴＲＯＤＵＣＴＩＯＮＭｏｌｅｃｕｌａｒｎｉｔｒｏｇｅｎ（Ｎ２）ｉｓｏｎｅｏｆｔｈｅｍｏｓｔｃｏｍｍｏｎｎｏｎｈｙｄｒｏｃａｒｂｏｎｃｏｍｐｏｎｅｎｔｓｉｎｇａｓｐｏｏｌｓ（Ｚｈｕ，１９９４）．Ｎ２ｒｉｃｈｇａｓｐｏｏｌｓｈａｖｅｂｅｅｎｄｉ...

关键词： nitrogen isotope origin of nitrogen natural gas ammomia sedimentary organic matter

A preliminary knowledge-driven prediction model of snail distribution in the Poyang Lake region

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Chinese Science Bulletin 2008年第1期53卷 115-123页

作者： ZHAO An1,2.3 & BAO ShuMing1 1 The Key Lab of Poyang Lake Ecological Environment and Resource Development, Jiangxi Normal university, Nanchang 33002., China 2.institute of Geographic Sciences and Resources {2., Chinese Academy of Sciences, Beijing 100101, China 3 School of Geography and environmental Sciences, Jiangxi Normal university, Nanchang 33002., China The Key Lab of Poyang Lake Ecological Environment and Resource Development Jiangxi Normal University Nanchang China institute of Geographic Sciences and Resources research Chinese Academy of Sciences Beijing China School of Geography and environmental Sciences Jiangxi Normal University Nanchang China

Present monitoring and prediction of schistosomiasis’s intermediate parasite, snail, are based on re-mote sensing image’s spectral signatures, and the calculation result is in fact an incom-plete-constraints solution. TM image of the Poyang Lake region on October 31, 2.05 was combined with GIS thematic data (DEM, boundary of the Poyang Lake, vegetation, soil and land use) to make a prediction on snail spatial distribution in the region by remote sensing, geo-informatics and knowl-edge-driven modeling according to mechanism of snail occurrence. Result shows that with change of overall fuzzy membership of snail occurrence from high to low, snail occurrence of the snail samples of validation group goes up to 81% within 10% high fuzzy membership range, denoting high efficiency of the model in predicting snail occurrence.

关键词：鄱阳湖区域蜗牛分布模糊分类血吸虫病

Temporal variations of δ^(18)O of atmospheric water vapor at Delingha

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Science China Earth Sciences 2008年第7期51卷 966-975页

作者： YIN ChangLiang1, YAO TanDong2. TIAN LiDe2. LIU DongNian3, YU WuSheng2.& QU DongMei2.1 State Key Laboratory of Cryoshperic Science, Cold and Arid Regions environmental and Engineering research {2., Chinese Academy of Sciences, Lanzhou 730000, China 2.Laboratory of Environment and Processes, {2. of Tibetan Plateau research, Chinese Academy of Sciences, Beijing 100085, China 3 Meteorological Observatory of Haixi Prefecture of Qinghai Province, Delingha 817000, China 1. State Key Laboratory of Cryoshperic Science Cold and Arid Regions Environmental and Engineering Research Institute Chinese Academy of Sciences Lanzhou 730000 China 2. Laboratory of Environment and Processes Institute of Tibetan Plateau Research Chinese Academy of Sciences Beijing 100085 China 3. Meteorological Observatory of Haixi Prefecture of Qinghai Province Delingha 817000 China

Oxygen stable isotope of atmospheric water vapor is widely used to study the modern process of cli- mate. Atmospheric water vapor samples were collected at Dlingha, northeast of Tibetan Plateau during the period from July 2.05 to February 2.06. The variation of δ18O and the relationships between δ18O and both the temperature and specific humidity are analyzed in this paper. Results show that the sea- sonal variation of δ18O of atmospheric water vapor at Delingha is remarkable with higher δ18O in summer and lower δ18O in winter. The temporal variation of vapor δ18O shows obvious fluctuations, with magnitude of over 37‰. The daily variation of the δ18O is highly correlated with air temperature. The relationship between δ18O and atmospheric water vapor content is complex. Study shows that δ18O of atmospheric water vapor is positively correlated with specific humidity in winter in seasonal scale and inversely correlated with specific humidity in summer rainy period. The δ18O values of at- mospheric water vapor are lower than those of precipitation at Delingha, and the average difference is 10.7‰. Variations of δ18O of atmospheric water vapor is also found to be affected by precipitation events, The model results show that the precipitation effect could have caused the vapor δ18O in the raining season to lower by 7% in average in July and August.

关键词： Delingha δ18O atmospheric water vapor