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Response of flood discharging capacity to the deterioration of the lower Yellow River

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Science China(Technological Sciences) 2004年第z1期47卷 152-160页

作者： LI Wenxue1, LI Yong2. YAO Wenyi2. SU Yunqi2.& ZHANG Xiaohua2.1. Yellow River engineering Consulting Co. ltd., Zhengzhou 450003, China 2. Yellow River {2. of Hydraulic {2., Zhengzhou 450003, China Yellow River Engn Consulting Co ltd Zhengzhou 450003 Peoples R China Yellow River Inst Hydraul Res Zhengzhou 450003 Peoples R China

Based on the clarifications of the deterioration characteristics of the lower Yellow River (LYR), the influence of river deterioration on flood discharging capacity is studied through theoretical derivation and analysis of field data. This study indicates that response of flood discharging capacity to river deterioration is nonlinear. Sediment depositions in the main channel cause the reductions of dominant discharge and thus the increase of initial flood stage. Reductions in the channel width result in the increases of the rising rate of flood stage and the decrease of flood discharging capacity.

关键词： flood discharging capacity, boundary condition, deterioration, sediment, the lower Yellow River.

Migration Behavior of Impurity Iron in Silicon Melt Under Pulsed Electric Current

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Acta Metallurgica Sinica(English Letters) 2024年第5期37卷 889-903页

作者： Mengcheng Zhou Yaxiong Dai Changhao Liu shengli Ding Xinfang Zhang School of Metallurgical and Ecological engineering University of Science and Technology BeijingBeijing 100083China Guangdong Zhongnan Iron&Steel Co. Ltd.Guangdong 512123China

The impurity iron in silicon material will seriously affect the photoelectric conversion efficiency of silicon solar ***,the traditional silicon purification method has the disadvantages of long cycle,high energy consumption and serious *** this study,an efficient and green pulsed electric current purification technology is *** electromigration effect of iron elements,the current density gradient driving of iron phase,and the gravity of iron phase all affect the migration behavior of iron phase in silicon melt under pulsed electric *** of the depth of electrode insertion into the silicon melt,the solubility of iron in silicon decreases under the pulsed electric current,which helps to form the iron *** the same time,the iron phase tends to sink toward the bottom under the influence of *** the electrode is shallowly inserted,a non-uniform electric field is formed in the silicon melt,and the iron phase is mainly driven by the current density gradient to accelerate sink toward the *** the electrode is fully inserted,an approximately uniform electric field is formed in the silicon melt,and iron elements are preferentially migrated to the cathode by electromigration,forming iron phase sinking at the *** study of impurity iron migration behavior in silicon melt under pulsed electric current provides a new approach for the purification of polycrystalline silicon.

关键词： Metallurgical silicon Pulsed electric current Iron-rich phase Current density gradient Electromigration

research progress in the inner surface modification of metal tubes by plasma processing

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Progress in Natural Science:Materials International 2006年第11期16卷 1119-1126页

作者： ZHANG Guling~ 1,2.**, WU Xingfang~1, GU Weichao~2. CHEN Guangliang~2. FENG Wenran~2. NIU Erwu~2. LI Li~2. L Guohua~2. CHEN Huan~2. FAN Songhua~2. LIU Chizi~2.and YANG Size~2.1. School of Material Science and engineering, University of Science and Technology Beijing, Beijing 100083, China 2. Beijing National Laboratory for Condensed Matter Physics, institute of Physics, Chinese Academy of Sciences, Beijing 100080, China) School of Material Science and engineering University of Science and Technology Beijing Beijing 100083 China Beijing National Laboratory for Condensed Matter Physics Institute of Physics Chinese Academy of Sciences Beijing 100080 China

The recent progress in inner surface hardening of tubes by plasma processing is summerized. Several techniques of inner surface plasma source ion implantation and deposition are introduced, and their advantages and disadvantages are discussed. The basic principles, technical features and new progress of inner surface plasma source ion implantation methods for metal tubes, which were developed in our laboratory, are described in detail. And perspectives of the future technical development for inner surface ion implantation of tubes are presented.

关键词： PSII metal tubes inner surface surface modification.

An Evaluation Method for Combustion Characteristics of Coal in Cement Industry

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Journal of Wuhan University of Technology(Materials Science) 2010年第1期25卷 174-178页

作者：陶从喜 School of Environmental Science and engineering Tianjin University Tianjin Cement Industry Design and research institute Co Ltd.

As the coal combustion behaviors are rather complex in the cement industry, the traditional assessment method cannot be directly applied to evaluate the quality of coal. Based on the thermal analysis tests of more than 80 kinds of anthracite and bituminous coal, three evaluation parameters, namely, burning intensity （I）, average capacity of heat release （Q）, and general burning index （S） are presented, combining with the consideration of application and calciner types in the cement industry. Taking these three parameters into consideration together is necessary. Experimental results show that the coal with higher S, lower I and higher Q can be rated as the best for the calciner in the cement industry. The quantitative indexes are given to evaluate the bituminous coal and anthracite in this paper. This new assessment method has implications for the design of calciner in the cement industry.

关键词： coal burning intensity average capacity of heat release general burning index calciner

Distribution and characteristics of gravelly soil liquefaction in the Wenchuan M_s 8.0 earthquake

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Earthquake engineering and engineering Vibration 2010年第2期9卷 167-175页

作者： Cao Zhenzhong1,Hou Longqing2.Xu Hongmei2.and Yuan Xiaoming1 1. institute of engineering Mechanics,China Earthquake Administration,Harbin 150080,China 2. East China institute of Technology,Fuzhou 344000,China institute of engineering Mechanics China Earthquake Administration Harbin 150080 China

In this paper,a distribution map of gravelly soil liquefaction that was caused by the Wenchuan M8.0 earthquake in China is proposed based on a detailed field investigation and an analysis of geological soil profiles. The geological background of the earthquake disaster region is summarized by compiling geological cross sections and borehole logs. Meanwhile,four typical liquefied sites were selected to conduct sample drillings,dynamic penetration tests (DPT),and shear wave velocity tests,to understand the features of liquefied gravelly soil. One hundred and eighteen (118) liquefied sites were investigated shortly after the earthquake. The field investigation showed:(1) sandboils and waterspouts occurred extensively,involving thousands of miles of farmland,12. villages,eight schools and five factories,which caused damage to some rural houses,schools,manufacturing facilities and wells,etc.; (2. the Chengdu plain is covered by a gravelly soil layer with a thickness of 0 m to 541 m according to the geological cross sections; (3) there were 80 gravelly soil liquefied sites in the Chengdu plain,shaped as five belt areas that varied from 2. km to 40 km in length,and about ten gravelly soil liquefied sites distributed within Mianyang area; and (4) the grain sizes of the sampled soil were relative larger than the ejected soil on the ground,thus the type of liquefied soil cannot be determined by the ejected soil. The gravelly soil liquefied sites are helpful in enriching the global database of gravelly soil liquefaction and developing a corresponding evaluation method in further research efforts.

关键词： gravelly soil liquefaction borehole soil profile geological cross section grain size distribution Wenchuan earthquake

Effect of climatic change on snowmelt runoffs in mountainous regions of inland rivers in Northwestern China

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Science China Earth Sciences 2006年第8期49卷 881-888页

作者： WANG Jian1 & LI Shuo2.1. Cold and Arid Regions Environmental and engineering research {2., Chinese Academy of Sciences, Lanzhou 730000, China 2. College of Geography, Nanjing Normal University, Nanjing 2.0097, China 1. Cold and Arid Regions Environmental and engineering research {2. Chinese Academy of Sciences Lanzhou 730000 China 2. College of Geography Nanjing Normal University Nanjing 210097 China

Climatic change has significant impacts on snow cover in mid-latitude mountainous re- gions, in the meantime, spatial and temporal changes of snow cover and snowmelt runoffs are con- sidered as sensitive indicators for climatic change. In this study, the upper Heihe Watershed in the Qilian Mountains was selected as a typical area affected by snow cover and snowmelt runoffs in northwestern China. The changes in air temperatures, precipitation, snowfall and spring snowmelt runoffs were analyzed for the period from 1956 to 2.01. The results indicate that climatic warming was apparent, particularly in January and February, but precipitation just fluctuated without a clear trend. The possible changes of snowmelt runoffs in the upper Heihe watershed in response to a warming of 4℃ were simulated using Snowmelt Runoff Model (SRM) based on the degree-day factor algorithm. The results of the simulation indicate that a forward shifting of snow melting season, an increase in water flows in earlier melting season, and a decline in flows in later melting season would occur under a 4℃ warming scenario.

关键词： climatic changes, snowmelt runoff, SRM model, upper Heihe Watershed, simulating.

Synthetically adaptive robust filtering for satellite orbit determination

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Science China Earth Sciences 2004年第7期47卷 585-592页

作者： YANG Yuanxi1 & WEN Yuanlan2.1. Xi’an research institute of Surveying and Mapping, Xi抋’an 710054, China 2. College of Aerospace and Material {2., National University of Defense Technology, Changsha 410073, China 1. Xi’an research institute of Surveying and Mapping 710054 Xi’an China 2. College of Aerospace and Material engineering National University of Defense Technology 410073 Changsha China

The quality of the satellite orbit determination is rested on the knowledge of per-turbing forces acting on the satellite and stochastic properties of the observations, and the ability of controlling various kinds of errors. After a brief discussion on the dynamic and geometric orbit determinations, Sage adaptive filtering and robust filtering are reviewed. A new synthetically adaptive robust filtering based on a combination of robust filtering and Sage filtering is *** is shown, by derivations and calculations, that the synthetically adaptive robust filtering for orbit determination is not only robust but also simple in calculation. It controls the effects of the outliers of tracking observations and the satellite dynamical disturbance on the parameter esti-mates of the satellite orbit.

关键词： satellite orbit, Sage filtering, adaptive orbit determination, robust estimation.

Bipolar charged aerosol agglomeration and collection by a two-zone agglomerator

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Journal of Environmental Sciences 2001年第3期13卷 276-279页

作者： XIANG Xiao dong 1, CHEN Bao zhi 1, COLBECK I 2.(1. School of Resource and Civil engineering, Northeastern University, Shenyang 110006, China. 2. institute for Environmental {2., Department of Biological and Chemical Sciences, University of Es School of Resource and Civil engineering Northeastern University Shenyang 110006 China.

In older to collect fine particles more efficiently, a new-type electrostatic agglomerator with two zones was developed. The distinguishing feature of this electrostatic agglomerator is that the particles are bipolarly charged and coagulated in the same alternating electric field simultaneously. The silica flour with 2.fun mass median diameter and the smoke from burning wood powder were used as test aerosol. The comparison experimental results have shown that when the mean electric field is 4 kV/cm the collection efficiency of the new electrostatic agglomerator was 98.2. for silica flour and 67.4% for wood powder smoke, Under the same experimental condition. the collection efficiency of the electrostatic agglomerator with three zones was 97.4% for collecting silica flour and the collection efficiency of the electrostatic precipitator was 56.3% for wood powder smoke.

关键词： charged particle agglomeration alternating electric field electrostatic agglomerator (EA) electrostatic precipitator (ESP) collection efficiency

Bio-regeneration of p-complexation desulfurization adsorbents

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Science China Chemistry 2005年第6期48卷 538-544页

作者： LI Wangliang1,2. XING Jianmin1, XIONG Xiaochao1,2. SHAN Guobin1,2.& LIU Huizhou1 1. Laboratory of Separation Science and engineering, institute of Process engineering, Chinese Academy of Sciences, Beijing 100080, China 2. Graduate School of the Chinese Academy of Sciences,Beijing 100039, China 1. Laboratory of Separation Science and engineering Institute of Process Engineering Chinese Academy of Sciences 100080 Beijing China 2. Graduate School of the Chinese Academy of Sciences 100039 Beijing China

The coupling of adsorption desulfurization and biodesulfurization is a new approach to produce clean fuels. Sulfur compounds are firstly adsorbed on adsorbents, and then the ad-sorbents are regenerated by microbial conversion. p-Complexation adsorbent, Cu(I)-Y, was ob-tained by ion exchanging Y-type zeolite with Cu2. and then by auto-reduction in helium at 450℃ for 3 h. Dibenzothiophene (DBT) was used as a model compound. The effects of cell concentra-tion, volume of oil phase, the ratio of aqueous phase to adsorbent on DBT desorption by a bac-terium were studied. The amounts of DBT desorbed and 2.HBP produced can be apparently increased with addition of n-octane. BDS activity can be improved by increasing cell concentra-tion and the ratio of water-to-adsorbent. 89% of DBT desorbed from the adsorbents can be converted to 2.HBP within 6 h and almost 100% within 2. h, when the volume ratio of oil-to-water was 1/5 mL/mL, the cell concentration was 60 g·L?1, and the ratio of adsorbent-to-oil was 0.03 g·mL?1. The amount of 2.HBP produced was strongly dependent on the volume ratio of oil-to- water, cell concentration and amount of adsorbent. Adsorption capacity of the regenerated ad-sorbent is 95% that of the fresh one after being desorbed with Pseudomonas delafieldii R-8, washed with n-octane, dried at 100℃ for 2. h and auto-reduced in He.

关键词： adsorption desulfurization p-complexation adsorbents bio-regeneration Pseudomonas delafieldii desorption.