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paleoenvironments indicated by the fossil mammalian assemblages from red clay-loess sequence in the Chinese Loess plateau since 8.0 Ma B.p.

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Science china Earth Sciences 2006年第5期49卷 518-530页

作者： XUE Xiangxu1,2, ZHANG Yunxiang1,2 & YUE Leping1,2 1. state key laboratory of Continent Dynamics (Northwest University), institute of Cenozoic Geology and environment, De- partment of Geology, Northwest University, Xi’an 710069, china 2. institute of Earth environment, state key laboratory of Loess and Quaternary Geology, Chinese Academy of Sciences, Xi’an 710075, china 1. state key laboratory of Continent Dynamics (Northwest University) Institute of Cenozoic Geology and Environment Department of Geology Northwest University Xi’an 710069 China 2. institute of Earth environment State Key Laboratory of Loess and Quaternary Geology Chinese Academy of Sciences Xi’an 710075 China

Information from eleven profiles of eolian earthy red silty clay and loess of the middle of the Late Miocene to Holocene age have been studied and correlated. A complete summary profile with projected isotopic ages and fossil-bearing beds has been assembled. The profile is subdivided into 12 stratigraphic units proceeding from the lower (older) to the upper (younger) one. The character of mammalian assemblages contained in each unit was analyzed and the corresponding pa- leo-climatic environments were deduced. The environmental character of each period and the change from the middle of the Late Miocene at about 8.0 Ma B.p. up to the Holocene progressed from the hot semiarid and semi-moist, warmer-moist, warm-moister of the Late Miocene. To slightly less warm moist, cool-dry, slight-warmer-moister of the pliocene; later the cool to cold dry periods alternated frequently with the mild semiarid and semi-moist periods of the Quaternary. Vegetation progressed from the grasslands with sparse woods, wooded shrub-grasslands and subtropical forest-grasslands of the Late Miocene age to sparse grasslands and dry grasslands of the pliocene; and to sparse grasslands, dry grasslands and tundras of the Quaternary. The climate changes in the Neogene were of low-amplitute in a generally warm-humid background. Those of the Quaternary were of higher am- plitude with a longer phase. Cool or cold dry and slightly warm semiarid and semi-moist climates al- ternated on a generally cool-dry background. The tendency since the start of the Quaternary was the change to more northern and western shift in the Loess plateau, with progressively cooler and dryer conditions. The dramatic uplift of the Qinghai-Xizang (Tibet) plateau and the forming and expansion of the Arctic ice sheet might be the main reasons of the more pronounced changes in the Quaternary.

关键词： paleoenvironment, mammalian fossils, eolian red clay-loess sequence, Loess plateau.

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rESEArCH ON HYDrODYNAMIC AND water QUALITY MODEL FOr TIDAL rIVEr NETWOrKS

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Journal of Hydrodynamics 2003年第2期15卷 64-70页

作者： Xu Zu xin, Lu Shi qiang School of environment Science and Engineering, state key laboratory of pollution Control and resource reuse, Tongji University, Shanghai 200092, china School of environment Science and Engineering State Key Laboratory of Pollution Control and Resource Reuse Tongji University Shanghai 200092 China

Hydrodynamic and water quality model for tidal river network is set up withMIKE11 modeling system, according to the features of tidal river networks in plain area. The modelwas calibrated using the hydrological and water quality data of 1999, and the results show that thesimulated values agree with the measured data very well. This model is used to numerically analyzethe effects of low flow augmentation on hydrodynamic and water quality conditions of Suzhou *** simulation results show that the flow augmentation can increase net discharge of Suzhou Creekand improve its ability of re-aeration; and its concentration of dissolved oxygen in the rivernetworks can also increase correspondingly.

关键词： tidal river network water quality model suzhou creek low flow augmentation

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Microwave photocatalytic degradation of rhodamine B using TiO_2 supported on activated carbon:Mechanism implication

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Journal of environmental Sciences 2009年第2期21卷 268-272页

作者： HE Zhong,YANG Shaogui,JU Yongming,SUN Cheng state key laboratory of pollution Control and resource reuse,School of the environment,Nanjing University,Nanjing 210093,china. state key laboratory of pollution Control and resource reuse School of the Environment Nanjing University Nanjing 210093 China

The photocatalytic degradation of rhodamine B （rhB） was carried out using TiO2 supported on activated carbon （TiO2-AC） under microwave irradiation. Composite catalyst TiO2-AC was prepared and characterized using X-ray diffraction （XrD）, transmission electron microscopy （TEM） and Brunauer-Emmett-Teller （BET）. In the process of microwave-enhanced photocatalysis （MpC）, rhB （30 mg/L） was almost completely decoloured in 10 min, and the mineralization efficiency was 96.0% in 20 min. The reaction rate constant of rhB in MpC using TiO2-AC by pseudo first-order reaction kinetics was 4.16 times of that using Degussa p25. Additionally, according to gas chromatography/mass spectrometry （GC/MS） and liquid chromatography/mass spectrometry （LC/MS） identification, the major intermediates of rhB in MpC included two kinds of N-de-ethylation intermediates （N,N-diethyl-N＇-ethyl-rhodamine （DEr））, oxalic acid, malonic acid, snccinic acid, and phthalic acid, maleic acid, 3-nitrobenzoic acid, and so on. The degradation of rhB in MpC was mainly attributed to the destruction of the conjugated structure, and then the intermediates transformed to acid molecules which were mineralized to water and carbon dioxide.

关键词： microwave photocatalytic WiO2, activated carbon rhodamine B degradation mechanism

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An Anthropomorphic robot Hand Developed Based on Underactuated Mechanism and Controlled by EMG Signals

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Journal of Bionic Engineering 2009年第3期6卷 255-263页

作者： Da-peng Yang~1 Jing-dong Zhao~1 Yi-kun Gu~1 Xin-qing Wang~1 Nan Li~1 Li Jiang~1Hong Liu~(1,2) Hai Huang~3 Da-wei Zhao~41.state key laboratory of robotics and System,harbin institute of technology,harbin 150001,p.r.china2.institute of robotics and Mechatronics,German Aerospace Center,Munich 82230,Germany3.College of Shipbuilding Engineering,harbin Engineering University,harbin 150001,p.r.china4.College of Automation,harbin Engineering University,harbin 150001,p.r.china [a]state key laboratory of robotics and System Harbin Institute of Technology Harbin 150001 P. R. China [b]Institute of Robotics and Mechatronics German Aerospace Center Munich 82230 Germany [c]College of Shipbuilding Engineering Harbin Engineering University Harbin 150001 P. R. China [d]College of Automation Harbin Engineering University Harbin 150001 P. R. China

When developing a humanoid myo-control hand,not only the mechanical structure should be considered to afford a high dexterity,but also the myoelectric (electromyography,EMG) control capability should be taken into account to fully accomplish the actuation *** paper presents a novel humanoid robotic myocontrol hand (Ar hand Ⅲ) which adopted an underac- tuated mechanism and a forearm myocontrol EMG *** Ar hand Ⅲ has five fingers and 15 joints,and actuated by three embedded *** can be found within each finger and between the rest three fingers (the middle finger,the ring finger and the little finger) when the hand is grasping *** the EMG control,two specific methods are proposed:the three-fingered hand gesture configuration of the Ar hand Ⅲ and a pattern classification method of EMG signals based on a statistical learning algorithm-Support Vector Machine (SVM).Eighteen active hand gestures of a testee are recognized ef- fectively,which can be directly mapped into the motions of Ar hand Ⅲ.An on-line EMG control scheme is established based on two different decision functions:one is for the discrimination between the idle and active modes,the other is for the recog- nition of the active *** a result,the Ar hand Ⅲ can swiftly follow the gesture instructions of the testee with a time delay less than 100 ms.

关键词： humanoid hand underactuated mechanism EMG control suppon vector machine

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A novel aminated polymeric adsorbent for removing refractory dissolved organic matter from landfill leachate treatment plant

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Journal of environmental Sciences 2009年第8期21卷 1089-1095页

作者： ZHANG Long, LI Aimin, WANG Jinnan, LU Yufei, ZHOU Youdong state key laboratory of pollution Control and resource reuse, School of the environment, Nanjing University, Nanjing 210093, china. [a]state key laboratory of pollution Control and resource reuse School of the Environment Nanjing University Nanjing 210093 China

refractory dissolved organic matter （DOM） from landfill leachate treatment plant was with high dissolved organic carbon （DOC） content. An aminated polymeric adsorbent NDA-8 with tertiary amino groups and sufficient mesopore was synthesized, which exhibited high adsorption capacity to the DOM （raw water after coagulation）. resin NDA-8 performed better in the uptake of the DOM than resin DAX-8 and A100. Electrostatic attraction was considered as the decisive interaction between the adsorbent and adsorbate. Special attention was paid to the correlation between porous structure and adsorption capacity. The mesopore of NDA-8 played a crucial role during uptake of the DOM. In general, resin in chloride form performed a higher removal rate of DOC. According to the colunm adsorption test, total adsorption capacity of NDA-8 was calculated to 52.28 mg DOC/mL wet resin. 0.2 mol/L sodium hydroxide solution could regenerate the adsorbent efficiently.

关键词： electrostatic interactions chemically modified resin coagulation adsorption pore structure

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Advanced fluid-typing methods for NMr logging

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petroleum Science 2011年第2期8卷 163-169页

作者： Xie ranhong Xiao Lizhi state key laboratory of petroleum resource and prospecting China University of Petroleum Beijing 102249 China key laboratory of Earth prospecting and Information technology China University of Petroleum Beijing 102249 China

In recent years, nuclear magnetic resonance （NMr） has been increasingly used for fluid- typing in well-logging because of the improved generations of NMr logging tools. This paper first discusses the applicable conditions of two one-dimensional NMr methods： the dual TW method and dual TE method. Then, the two-dimensional （T2, D） and （T2, T1） NMr methods are introduced. These different typing methods for hydrocarbon are compared and analyzed by numerical simulation. The results show that the dual TW method is not suitable for identifying a macroporous water layer. The dual TE method is not suitable for typing gas and irreducible water. （T2, T1） method is more effective in typing a gas layer. In an oil-bearing layer of movable water containing big pores, （T2, T1） method can solve the misinterpretation problem in the dual TWmethod between a water layer with big pores and an oil layer. The （T2, T1） method can distinguish irreducible water from oil of a medium viscosity, and the viscosity range of oil becomes wide in contrast with that of the dual TW method. The （T2, D） method is more effective in typing oil and water layers. In a gas layer, when the SNr is higher than a threshold, the （T2, D） method can resolve the overlapping T2 signals of irreducible water and gas that occurs due to the use of the dual TE method. Twodimensional NMr for fluid-typing is an important development of well logging technology.

关键词： NMr logging one-dimensional NMr two-dimensional NMr reservoir evaluation fluidtyping

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AppLICATION OF SWAT MODEL IN THE UpSTrEAM waterSHED OF THE LUOHE rIVEr

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Chinese Geographical Science 2003年第4期13卷 334-339页

作者： ZHANG Xue-song, HAO Fang-hua, CHENG Hong-guang, LI Dao-feng (state key laboratory of water environment Simulation,institute of environmental Sciences, Beijing Normal University,Beijing 100875,p. r. china) state key laboratory of water environment Simulation Institute of Environmental Sciences Beijing Normal University Beijing 100875 P. R. China

In the Huanghe (Yellow) river basin,soil erosion is a serious problem,while runoff and sediment yield simulation has not been extensively studied on the basis of GIS (Geographic Information System) and distributed hydrological model. GIS-based SWAT (Soil and water Assessment Tool) model was used to simulate runoff and sediment in the Huanghe river basin. The objective of this paper is to examine the applicability of SWAT model in a large river basin with high sediment runoff modulus,which could reach 770t/(km2·a). A two-stage "Brute Force" optimization procedure was used to calibrate the parameters with the observed monthly flow and sediment data from 1992 to 1997,and with input parameters set during the calibration process without any change the model was validated with 1998-1999’s observed data. Coefficient of examination (r2) and Nash-Suttcliffe simulation efficiency (Ens) were used to evaluate model prediction. The evaluation coefficients for simulated flow and sediment,and observed flow and sediment were all above 0.7,which shows that SWAT model could be a useful tool for water resources and soil conservation planning in the Huanghe river basin.

关键词： luohe river watershed SWAT model sediment flow

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Influence of Ordovician carbonate reservoir beds in Tarim Basin by faulting

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Science china Earth Sciences 2008年第S2期51卷 53-60页

作者： L XiuXiang1,2,YANG Ning1,2,ZHOU XinYuan3,YANG HaiJun3 & LI JianJiao1,2 1 Faculty of Natural resource & Information technology,china University of petroleum,Beijing 102249,china 2 state key laboratory of petroleum resource and prospecting,china University of petroleum,Beijing 102249,china 3 Tarim Oilfield,petrochina,Korla 841000,china china Univ petr Fac Nat Resource & Informat Technol Beijing 102249 Peoples R China china Univ petr State Key Lab Petr Resource & Prospecting Beijing 102249 Peoples R China petrochina Tarim Oilfield Korla 841000 Peoples R China

The quality of the Ordovician carbonate reservoir beds in the Tarim Basin is closely related to the development of secondary pores,fractures and cavities. Karstification is important in improving the properties of reservoir beds,and karstification related to unconformity has caught wide attention. Compared with the recent research on the unconformity karst reservoir bed improvement,this paper shows a new way of carbonate reservoir bed transformation. Based on field survey,core and slices observation,transformation of Ordovician carbonate reservoir beds by faulting can be classified into three types: (1) Secondary faults and fracturs generated by faulting improved carbonate reservoir bed properties,which were named the Lunnan or Tazhong82 model; (2) upflow of deep geothermal fluids caused by faulting,with some components metasomatizing with carbonate and forming some secon-dary deposit,such as fluorite. It can improve carbonate reservoir bed properties obviously and is named the Tazhong 82 model; and (3) the faulting extending up to the surface increased the depth of supergene karstification and the thickness of reservoir bed. It is named the Hetianhe model. Trans-formation effect of carbonate reservoir beds by faulting was very significant,mainly distributed on the slopes or on the edge or plunging end of the uplift.

关键词： carbonate faulting reservoir transformation Ordovician Tarim Basin

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Characteristics of fluid substitution in porous rocks

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petroleum Science 2009年第2期6卷 139-145页

作者： Li Shengjie School of resource and Information technology China University of Petroleum Beijing 102249 China state key laboratory of petroleum resource and prospecting China University of Petroleum Beijing 102249 China key laboratory of CNpC Geophysical Exploration China University of Petroleum Beijing 102249 China

Analysis of the effect of changes in fluid properties of rocks on the compressional-wave velocity Vp and shear-wave velocity Vs is very important for understanding the rock physical properties, especially in oilfield exploration and development. The fluid substitution process was analyzed by using ultrasonic measurement and theoretical calculations. The results showed that the effect of fluid substitution on the rock elastic modulus was mainly controlled by fluid properties, saturation, and confining pressure. For a rock with specific properties and porosity, the result of theoretical prediction for fluid substitution accorded with the experimental result under high confining pressure （higher than 60 Mpa for our experimental data）, but failed to describe the trend of experimental result under low confining pressure and Vp predicted by Gassmann＇s equation was higher than that measured by experiment. A higher porosity resulted in stronger sensitivity of the bulk modulus of saturated rocks to the change of fluid properties.

关键词： Fluid substitution velocity bulk modulus porosity saturation

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Effect of high-strength ammonia nitrogen acclimation on sludge activity in sequencing batch reactor

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Journal of environmental Sciences 2010年第11期22卷 1683-1688页

作者： Feifei Wang, Yuanhong Ding, Lei Ge, Hongqiang ren, Lili Ding state key laboratory of pollution Control and resource reuse, School of the environment, Nanjing University, Nanjing 210093, china. [a] state key laboratory of pollution Control resource reuse School of the Environment Nanjing University Nanjing 210093 China

The effect of high-strength ammonia nitrogen acclimation on sludge activity in sequencing batch reactor （SBr） was investigated. Two batch experiments, rUN1 and rUN2, were conducted with the influent ammonia nitrogen concentrations 60 and 500 mg/L, respectively. The sludges inoculated from rUN1 and rUN2 were used to treat a series of influent with ammonia nitrogen concentrations of 59, 232, 368, 604 and 1152 mg/L. It is found that the activated sludge acclimated to higher ammonia nitrogen concentrations revealed higher COD and NH 4 ＋ -N removal efficiencies, and slower DHA decrease. The results confirmed that the activities of the bacteria in activated sludge in SBr were inhibited by high-strength ammonia nitrogen, whereas the activated sludge acclimated to high-strength ammonia nitrogen showed substantial resistance to inhibition by influents containing high levels of ammonia nitrogen.

关键词： activated sludge sequencing batch reactor high-strength ammonia nitrogen dehydrogenase activity

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