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Effect of activation agents on the surface chemical properties and desulphurization performance of activated carbon

science china(Technological sciences) 2010年第9期53卷 2515-2520页

作者： ZHANG XiangLan,ZHANG Yan,WANG shuangsheng,ZHANG JingJing & ZHOU Wei school of Chemical and Environmental Engineering,china university of Mining and Technology ({2.),{2. 100083.china 1. school of Chemical and Environmental Engineering China University of Mining and Technology (Beijing) Beijing 100083 China

Flue gas pollution is a serious environmental problem that needs to be solved for the sustainable development of *** surface chemical properties of carbon have great influence on its desulphurization performance.A series of activated carbons (ACs) were prepared using HNO3,H2.2.NH3·H2. and steam as activation agents with the aim to introduce functional groups to carbon surface in the ACs preparation *** ACs were physically and chemically characterized by iodine and sO2.adsorption,ultimate analysis,Boehm titration,and temperature-programmed reduction (TPR).Results showed that the iodine number and desulphurization capacity of NH3·H2. activated carbon (AC-NH3) increase with both activation time,and its desulphurization capacity also increases with the concentration of activation ***,HNO3 activated carbon (AC-HNO3) and H2.2.activated carbon (AC-H2.2. exhibit more complex *** their iodine numbers increase monotonously with activation *** with steam activated AC (AC-H2.),the nitrogen content increases 0.2.2. in AC-NH3 and 0.077% in *** amount of total basic site on AC-HNO3 is 0.19 mmol·g-1 higher than that on AC-H2..H2.2.activation introduces an additional 0.08 mmol·g-1 carboxyl groups to AC surface than that introduced by steam *** desulphurization capacity of ACs in simulate flue gas desulphurization decreases as follows: AC-NH3 > AC-HNO3 > AC-H2.2.> *** sequence is in accord with the sO2.catalytic oxidation/oxidation ratio in the absence of oxygen and the oxidation property reflected by *** the presence of oxygen,all adsorbed sO2.on ACs can be oxidized into *** desulphurization capacity increases differently according to the activation agents;the desulphurization capacity of AC-NH3 and AC-HNO3 improves by 4.8 times,yet AC-H2. increases only by 2.62.as compared with the desulphurization of corresponding ACs in absence of oxygen.

关键词： activated carbon activation agent surface chemical property desulphurization TPR

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Monitoring of rice crop using ENVIsAT AsAR data

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science china Earth sciences 2006年第7期49卷 755-763页

作者： DONG Yanfang1, 2. sUN Guoqing1,3 & PANG Yong4 1. state Key laboratory of Remote sensing science, Institute of Remote sensing Applications, Chinese Academy of sciences, beijing 100101, {2. 2. Graduate university of Chinese Academy of sciences, beijing 100039, {2. 3. Department of geography, university of Maryland, College Park, MD 2.742. UsA 4. Forest Remote sensing lab, Research Institute of Forest Resource and Information Technology, Chinese Academy of For-estry, beijing 100091, {2. 1. state Key laboratory of Remote sensing science Institute of Remote Sensing Applications Chinese Academy of Sciences Beijing 100101 China 2. Graduate university of Chinese Academy of sciences Beijing 100039 China 3. Department of geography University of Maryland College Park MD 20742 USA 4. Forest Remote sensing lab Research Institute of Forest Resource and Information Technology Chinese Academy of Forestry Beijing 100091 China

Because of the cloudy conditions during the rice growth period, rice is one of the agri-cultural crops most suited to monitoring with the sAR instruments. Backscatter response measured by sAR is correlated with rice conditions, including height, density, biomass and structure, which are variable at different growing stages. In this paper, multi-date ENVIsAT AsAR Alternating Polarization Mode (APMode) imageries were acquired during the rice crop growing cycle. At the same time, the rice parameters were measured in field. A continuous canopy model was used to compute the back-scattering from rice fields during the growth cycle, and the relationship between rice parameters and radar backscattering coefficients from both AsAR and modeling was analyzed. The effects of polari-zation, incidence angle and polarization on radar backscattering coefficients were analyzed. It was found that simulated radar backscatter has similar trends as AsAR data. This will be meaningful for the further research of rice parameters estimation from AsAR data. Different features show signifi-cantly different signatures in AsAR images and they follow some certain laws, so rice area can be accurately mapped by using multi-temporal sAR images, then rice yield can be estimated.

关键词： rice, AsAR, radar backscattering, model.

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Anisotropic damage coupled modeling of saturated porous rock

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science china(Technological sciences) 2010年第10期53卷 2681-2690页

作者： LU YingFa1,2. WU XinXing1,2.& sHAO JianFu3 1 Key laboratory of geological Hazards on Three Gorges Reservoir Area, Ministry of Education, {2. Three Gorges university, Yichang 443002. {2. 2.school of Civil Engineering, Wuhan university, Wuhan 430071, {2. 3 university of sciences and Technologies of Lille, Lille 59655, France 1. Key laboratory of geological Hazards on Three Gorges Reservoir Area Ministry of Education China Three Gorges University Yichang 443002 China2. School of Civil Engineering Wuhan University Wuhan 430071 China3. University of Sciences and Technologies of Lille Lille 59655 France

It is widely acknowledged that the natural rock mass is anisotropic and its failing type is also non-isotropic. An orthotropic elastic damaged model has been proposed in which the elastic deformation,the damaged deformation and irreversible deformation can be identified respectively. A second rank damage tensor is employed to characterize the induced damage and damage evolution related to the propagation conditions of microcracks. A specific form of the Gibbs free energy function is used to obtain the effective elastic stiffness and the limited scopes of damage parameters are suggested. The model’s parameter determination is proposed by virtue of conventional tri-axial test. Then,the proposed model is developed to simulate the coupled hydraulic mechanical responses and traction behaviors in different loading paths of porous media.

关键词： anisotropy damage modeling saturated rock tensile failure

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Relationships between bacterial-algal proliferating and mass extinction in the Late Devonian Frasnian-Famennian transition:Enlightening from carbon isotopes and molecular fossils

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science china Earth sciences 2005年第10期48卷 1656-1665页

作者： GONG Yiming1,2. XU Ran1, TANG Zhongdao1, sI Yuanlan3 & LI Baohua4 1. Faculty of Earth science and state Key laboratory of geological Processes and Mineral Resources, {2. university of geosciences, Wuhan 430074, {2. 2. Institute of Resources & Environments, Henan Polytechnic university, Jiaozuo 454003, {2. 3. Department of Computer science, south-Central university for Nationalities, Wuhan 430074, {2. 4. laboratory of Marine geology, Tongji university, shanghai 2.0092. {2. Faculty of Earth science and state Key laboratory of geological Processes and Mineral Resources {2. university of geosciences Wuhan {2. Institute of Resources & Environments Henan Polytechnic university Jiaozuo china Department of Computer science south-Central university for Nationalities Wuhan china laboratory of Marine geology Tongji {2. shanghai china

studies show positive shifts of inorganic and organic carbon isotope values (δ 13Ccarb and δ 13Ckerogen) from +0.43 (‰ V-PDB) to +3.54 (‰ V-PDB) and from ?2..38 (‰ V-PDB) to ?2..14 (‰ V-PDB), respectively, B* (Ba* = Ba/ (Al2.3 X 15%)) values from 0.015 to 0.144, TOC values from 0.02. to 0.2.%, V/Cr values from 0.3 to 2.0, sr/Ba values from 3.2. to 49.50 in the Late Devonian Frasnian Upper rhenana zone to the top linguiformis zone of the Yangdi sec-tion deposited in carbonate slope facies of Guilin, Guangxi, south china, which indicates that biomass, productivity, organic carbon burial and salinity increase and that oxygenation near the boundary between sediments and waters decreases from the Late Devonian Frasnian Upper rhenana zone to the top linguiformis zone. Abundance of molecular fossils increases and normal alkanes, isoprenoid hydrocarbon, terpanes and steranes are dominated from the Late Devonian Frasnian to the bottom of Famennian, which shows that the predecessors of molecular fossils of the Frasnian-Famennian (F-F) transition are dominated by marine phytoplankton, zooplankton and benthic bacteria with no photosynthesis. Therefore, it is considered that the F-F transitional mass extinction with a multistage, selection and global synchronizing was caused by bacte-rial-algal proliferating, continuing deterioration of the shallow marine ecoenvironment of the mid-dle-lower latitudes. A simple cause and effect chain can be expressed as: appearance of seed plants and multi-storied forests → enhanced chemical and biochemical weathering and pe-dogenesis → wide development of soils → increasing riverine nutrient fluxes in epicontinental sea → from superoligotrophic to eutrophic in epicontinental sea → proliferating of marine phyto-plankton and zooplankton → frequent red tide and anoxia → mass extinction of shallow marine organisms in the middle-lower latitudes. It is worth notice that the factor drawdown of atmos-pheric Pco2. climatic cooling and sea level falling c

关键词： mass extinction, bacteria-algae, carbon isotopes, molecular fossils, biodiversity, Late Devonian, Guangxi, south china.

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Optimal user scheduling and power control in multi-user cognitive broadcast systems

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science china(Information sciences) 2012年第6期55卷 1402-1414页

作者： WANG QunHuan 1,2.3,WANG HuiMing 1,2.3 & YIN QinYe 1,3 1 school of Electronic and Information Engineering,Xi'an Jiaotong university,Xi'an 710049,china 2.state Key {2. for Integrated services Networks,Xidian university,Xi'an 710071,china 3 Ministry of Education Key {2. for Intelligent Networks and Network security,Xi'an Jiaotong university,Xi'an 710071,china. 1. school of Electronic and Information Engineering Xi’an Jiaotong University Xi’an 710049 China2. State Key Lab for Integrated Services Networks Xidian University Xi’an 710071 China3. Ministry of Education Key Lab for Intelligent Networks and Network Security Xi’an Jiaotong University Xi’an 710071 China

Cognitive radio systems should not only have the ability to sense and exploit "frequency spectrum holes",but also the ability to sense and utilize "spatial spectrum holes".In this paper,we consider the issue of maximizing the throughput of the cognitive systems by fully utilizing "spatial spectrum holes" brought in by multiple cognitive users,in the scenario where a pair of licensed users and a cognitive broadcast system share multiple spectrum *** exploiting the channel reciprocity under the premise that the licensed system adopts the time-division-duplexing (TDD) mode,we propose a more practical cognitive access scheme that can sense the interference at the licensed user caused by the cognitive transmitter,based on the existing feedback signals from the licensed user to the licensed base *** both interferences from the licensed base station to the cognitive receiver and from the cognitive transmitter to the licensed user into consideration,we investigate the optimal user scheduling and power allocation scheme that can maximize the ergodic sum rate of the cognitive *** show that scheduling the user whose channel gain to interference and noise ratio (CGINR) is the largest for each frequency band is *** also derive the dynamic power allocation scheme meeting the three practical constraints,i.e.,the transmitter's average transmission power constraint,the power amplifier's instantaneous transmission power constraint,and the interference power constraint at the licensed *** result shows that in different coherent time intervals and different frequency bands,the power allocation has a multi-level waterfilling *** analysis shows that the strategy scheduling user with the largest CGINR introduces significant performance improvement compared with the traditional strategy scheduling user with the largest channel gain to noise ratio (CGNR).We also illustrate the impact of power constraints and the number of users on system p

关键词： cognitive radio distributed spatial spectrum holes opportunistic scheduling power allocation

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Preparation of Nanosized AlOOH and Its Application in Polymer-inorganic Nanocomposites

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Journal of Wuhan university of Technology(Materials science) 2008年第5期23卷 638-643页

作者：廖海达 state Key lab of Advanced Technology for Materials synthesis and Processing Wuhan University of Technology College of Chemistry and Ecological Engineering Guangxi University for Nationalities Key lab of Nonferrous Materials and New Processing Technology (Guangxi university Guilin University of Technology) Ministry of Education

With industrial grade Al（OH）3 as raw materials, the self dispersion nanosized AlOOH crystal powder were prepared by the sol-hydrothermal method. The results of XRD and TEM show that the nanosized AlOOH could automatically disperse to a single-dispersing state in water without surface modification, dispersant, additive and accessional conditions （ultrasonic wave dispersing, ball-mill dispersing）. The application results of the product indicate that the nanosized AlOOH can be composed into a toughened nanocomposites without surface modification. Accordingly, the self dispersion characteristic and mechanism of hydrothermal crystallization and charging composite dispersion of nanosized AIOOH are found, and a new technique of preparing polymer/inorganic nanocomposites is proposed, which is called blending compositing new techniques of sol even dispersing at auasi-homogeneous phase.

关键词： self dispersion nanosized AlOOH peptizing-hydrothermal method nanocomposites

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Comparative Analysis on Microstructure and Mechanical Properties between EBW and TANDEM Welding of 7A52.Aluminum Alloy Joint

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稀有金属材料与工程 2011年第S4期40卷 68-73页

作者： Zhai Xiwei1,2.Chen Furong1,2.Bi Liangyan1,2.Zhang Chuanchen3 1College of Materials science and Engineering,Inner Mongolia university of Technology,Hohhot 010051,china2.ey {2.oratory of Materials Processing & Control Engineering of Inner Mongolia Autonomous Region,Hohhot 010051,china3school of Materials science and Engineering,university of science and Technology beijing,beijing 100083.china Inner Mongolia Univ Technol Coll Mat Sci & Engn Hohhot 010051 Peoples R China Key lab Mat Proc & Control Engn Inner Mongolia Au Hohhot 010051 Peoples R China Univ sci & Technol beijing Sch Mat Sci & Engn Beijing 100083 Peoples R China

The plates with 2.mm thickness of 7A52.aluminum alloy were welded by electron beam welding and TANDEM welding with ER5356 filler,*** microstructure and mechanical properties of the joints were *** results showed that the microstructure of EBW metal was finer and tighter than TANDEM *** heat-affected zone of the EBW joint was narrower,its hardness was higher and the tensile strength improved obviously compared to TANDEM *** quality control of the EBW joint was made without abnormal porosity,inclusions and ***,the EBW joint of 7A52.aluminum alloy showed excellent performance.

关键词： 7A52 aluminum alloy electron beam welding TANDEM welding microstructure mechanical properties

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Latest progress on interactions between VLF/ELF waves and energetic electrons in the inner magnetosphere

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science china Earth sciences 2010年第3期53卷 317-326页

作者： XIAO FuLiang1,2. ZONG QiuGang3, sU ZhenPeng4, TIAN Tian3 & ZHENG HuiNan4 1 school of Physics and Electronic sciences, Changsha university of science and Technology, Changsha 410004, china 2.state Key {2.oratory of space Weather, Chinese Academy of sciences, beijing 100190, china 3 Institute of space Physics and Applied Technology, Peking university, beijing 100871, china 4 CAs Key {2. for Basic Plasma science, school of Earth and space sciences, university of science and Technology of china, Hefei 2.002., china 1. school of Physics and Electronic sciences Changsha University of Science and Technology Changsha 410004 China2. State Key Laboratory of Space Weather Chinese Academy of Sciences Beijing 100190 China3. Institute of Space Physics and Applied Technology Peking University Beijing 100871 China4. CAS Key Lab for Basic Plasma Science School of Earth and Space Sciences University of Science and Technology of China Hefei 230026 China

Interactions between very/extremely low frequency (VLF/ELF) waves and energetic electrons play a fundamental role in dynamics occurring in the inner magnetosphere. Here, we briefly discuss global properties of VLF/ELF waves, along with the variability of the electron radiation belts associated with wave-particle interactions and radial diffusion. We provide cases of electron loss and acceleration as a result of wave-particle interactions primarily due to such waves, and particularly some preliminary results of 3D evolution of phase space density from our currently developing 3D code. We comment on the existing mechanisms responsible for acceleration and loss, and identify several critical issues that need to be addressed. We review latest progress and suggest open questions for future investigation.

关键词： wave-particle interaction VLF/ELF waves energetic electrons acceleration and loss inner magnetosphere

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The Design and Implementation of Qinghai Province geological Hazards Management Information system

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地学前缘 2009年第S1期16卷 42-43页

作者： Quan Xu~1,Qun Wang~1,Jun Chen~2.Wenqian Jiang~1 1.school of Information Technology,china university of {2.sciences(beijing),beijing 100083.china. 2.Department of Information,china Institute of {2.-Environment Monitoring,beijing 100081,china

The formation and development of geological hazards are extremely complex,depending on factors such as the topography,geology,meteorology, project,human activity,and so on;the geological hazards data include remarkable spatial characteristics and complex attribute *** the amount of geological hazards data is rapidly growing,it has become an urgent demand for geologists to

关键词： geological hazards mapGIs web services ajax

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The formation depth of coesite-bearing eclogite,Dabie UHPM zone,china,modified by tectono-original additional hydrostatic pressure

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Chinese science Bulletin 1999年第5期44卷 398-411页

作者： LU Guxian, CHEN Jing, LIU Ruixun and LI Xiaobo Institute of geomechanics , beijing 100081, {2. Electron Microscopy laboratory, Peking university, beijing 100871, {2. Department of geology, Peking university, beijing 100871, {2. Institute of geological Information , beijing 100037, {2. Institute of geomechanics Beijing China Electron Microscopy laboratory Peking University Beijing China Department of geology Peking University Beijing China Institute of Gelogical Information Beijing China

The knowledge that hydrostatic pressure is equal to the gravity value of the overlying rocks in studying a dynamic state of certain underground site is argued. It is suggested that the stress field T in the crust is a combination or superposition of total hydrostatic pressure P with differential stress σ,and the total hydrostatic pressure P at any point in the crust comprises two parts: one is spherical stress tensor Psub>Gsub> caused by the gravity, and the other is spherical stress tensor Psub>ssub> caused by tectonic stress; therefore P could not be attributed to the gravity of overlying rocks only. The results obtained by a finite-element simulation indicate that the tectono-original additional hydrostatic pressures Psub>ssub> decrease gradually from the compressive zone （psub>csub>sup>ssup>） to the shear zone (Psub>sHsub>sup>ssup>)and to the tensile zone （Psub>Tsub>sup>ssup>）, i.e.Psub>csub>sup>ssup>>Psub>sHsub>sup>ssup>>Psub>Tsub>sup>ssup> in the same depth. On the basis of the above-mentioned research, the method of measurement and calculation of metallogenetic depth corrected by Psub>ssub> is

关键词： formation depth tectonic additional hydrostatic pressure Dabie UHPM zone coesite-bearing eclogite expansion-cracking texture tectonic physicochemistry.

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