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Nematode Faunal Response to Grassland Degradation in Horqin Sandy Land

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Pedosphere 2007年第5期17卷 611-618页

作者： LIANG Wen-Ju ZHONG Shuang HUA Jian-Feng cAO cheng-You JIANG Yong Institute of Applied Ecology Chinese Academy of Sciences Shenyang 110016 （China） college of Sciences Northeastern University Shenyang 110004 （China） Graduate School of the chinese Academy of Sciences Beijing 100049 （China）

The responses of soil nematode communities to grassland degradation were studied under undegraded grassland (UG), degraded grassland (DG),and improved grassland (IG),in Horqin Sandy Land,Inner Mongolia,Northeast *** samples were collected at depths of 0-10,10-20,and 20-30 *** organic carbon (TOc) and total nitrogen (TN) exhibited positive effects on the total number of nematodes and trophic *** treatment effects were found in the total number of nematodes,plant parasites,and *** taken in the improved grassland could improve the number of omnivore-predators,especially in the deeper soil *** richness was lower in the DG treatment than in the IG and UG *** food web structure index (SI) was significantly higher in the UG and IG treatments than in the DG treatment.A higher SI suggested a food web with more trophic linkages and relatively healthy ecosystems.

关键词： functional groups grassland degradation Horqin Sandy Land soil nematodes

citizen sensors or extreme publics? Transparency and accountability interventions on the mobile geoweb

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International Journal of Digital Earth 2014年第7期7卷 516-533页

作者： Y.Georgiadou J.H.Lungo c.Richter Faculty of Geo-information Science and Earth Observation(ITc) University TwenteEnschedeThe Netherlands college of Information and communication Technologies(coIcT) University Dar es SalaamDar es SalaamTanzania

Transparency and Accountability(T&A)interventions are emergent social technologies in middle and low-income *** bring together citizen sensors,mobile communications,geo-browsers and social organization to raise public awareness on the extent of governance deficits,and monitor government’s(in)*** to their novelty,almost all we know about the effectiveness of T&A interventions comes from gray *** citizen sensors radically increase the transparency of the state,or are changes brought about by T&A interventions more likely to be incremental?We review the literature on transparency policies and describe their drivers,characteristics and supply-demand *** discuss promising cases of T&A interventions in East Africa,the empirical focus of an on-going collaborative research *** conclude that the effect of T&A interventions is more likely to be incremental and mediated by existing organizations and professional users who populate the space between the state and *** elements at the interface between supply and demand seem rather crucial for designers of T&A interventions:accountability-relevant data and extreme publics.

关键词： citizen sensors transparency accountability-relevant data extreme publics mobile geoweb

Effect of auxiliary ventilations on diesel particulate matter dispersion inside a dead-end entry

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International Journal of Mining Science and Technology 2015年第6期25卷 927-932页

作者： Zheng Yi Thiruvengadam Magesh Lan Hai Tien c.Jerry Department of Mining & Nuclear Engineering Missouri University of Science and Technology clean Air Power Inc. Division of Mining and Resources Engineering Department of Civil Engineering Monash University

Diesel particulate matter(DPM) is considered carcinogenic after prolonged exposure. This paper used computational fluid dynamics(cFD) method to study the effect of four auxiliary ventilation systems on DPM distribution in a dead-end entry with loading operation. The auxiliary ventilation systems considered include: blower fan and tubing; exhaust fan and tubing, jet fan, and push–pull system. A species transport model with buoyancy effect was used to examine the DPM dispersion pattern with unsteady state analysis. During the 200 s of the loading operation, high DPM levels were identified in the face and dead-end entry regions. This study can be used for mining engineer as guidance to design and setup of local ventilation. It can also be used for selection of DPM control strategies and DPM annual training for underground miners.

关键词： Diesel particulate mattercomputational fluid dynamicsAuxiliary ventilationDead-end entry

Fractal Basins in the Lorenz Model

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chinese Physics Letters 2011年第6期28卷 59-62页

作者： I.Djellit J.c.Sprott M.R.Ferchichi Laboratory of Mathematics Dynamics and ModelizationAnnaba-Algeria Department of Physics University of WisconsinMadisonWI 53706 USA

The Lorenz mapping is a discretization of a pair of differential *** illustrates the pertinence of computational *** describe complex dynamics,bifurcations,and chaos in the *** basins are displayed by numerical simula... 详细信息

关键词： equations chaos map

BLOSSOMS： Building Lightweight Optimized Sensor Systems on aMassive Scale

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Journal of computer Science & Technology 2005年第1期20卷 105-117页

作者： WenGao LionelM.Ni Zhi-WeiXu S.c.cheung Licui QiongLuo InstituteofcomputingTechnology ChineseAcademyofSciencesBeijing100080P.R.China DepartmentofcomputerScience TheHongKongUniversityofScienceandTechnologyClearWaterBayKowloonHongKongSpecialAdministrativeRegionP.R.China

As a joint effort between the chinese Academy of Sciences and the Hong KongUniversity of Science and Technology, the BLOSSOMS sensor network project aims to identify researchissues at all levels from practical applications down to the design of sensor nodes. In thisproject, a heterogeneous sensor array including different types of application-dependent sensors aswell as monitoring sensors and intruding sensors are being developed. Application-dependentpower-aware communication protocols are also being studied for communications among sensor nodes. Anontology-based middleware is built to relieve the burden of application developers from collecting,classifying and processing messy sensing contexts. This project is also developing a set of toolsallowing researchers to model, simulate/emulate, analyze, and monitor various functions of sensornetworks.

关键词： sensor network sensor node communication protocol middleware networksimulation network monitor

Simultaneous removal of chromium and arsenate from contaminated groundwater by ferrous sulfate:Batch uptake behavior

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Journal of Environmental Sciences 2011年第3期23卷 372-380页

作者： Xiaohong Guan Haoran Dong Jun Ma Irene M. c. Lo State Key Laboratory of Urban Water Resource and Environment Harbin Institute of Technology Harbin 150090 China Department of civil and Environmental Engineering The Hong Kong University of Science and Technology Hong Kong 999077 China

chromium and/or arsenate removal by Fe（Ⅱ） as a function of pH, Fe（Ⅱ） dosage and initial cr（Ⅵ）/As（Ⅴ） ratio were examined in batch tests. The presence of arsenate reduced the removal efficiency of chromium by Fe（Ⅱ）, while the presence of chromate significantly increased the removal efficiency of arsenate by Fe（Ⅱ） at pH 6-8, In the absence of arsenate, chromium removal by Fe（Ⅱ） increased to a maximum with increasing pH from 4 to 7 and then decreased with a further increase in pH. The increment in Fe（Ⅱ） dosage resulted in an improvement in chromium removal and the improvement was more remarkable under alkaline conditions than that under acidic conditions. chromium removal by Fe（Ⅱ） was reduced to a larger extent under neutral and alkaline conditions than that under acidic conditions due to the presence of 10 μtmol/L arsenate. The presence of 20 μmol/L arsenate slightly improved chromium removal by Fe（Ⅱ） at pH 3.9-5,8, but had detrimental effects at pH 6.7-9.8. Arsenate removal was improved significantly at pH 4-9 due to the presence of 10μmol/L chromate at Fe（Ⅱ） dosages of 20-60 μmol/L. Elevating the chromate concentration from 10 to 20μmol/L resulted in a further improvement in arsenate removal at pH 4.0-4.6 when Fe（Ⅱ） was dosed at 30-60 μmol/L.

关键词： chromium removal arsenate removal ferrous iron groundwater treatment

Nature of Surface Layer and Electrochemical Behavior of NaOH Hydrothermally Treated NiTi Alloy

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Journal of Materials Science & Technology 2004年第2期20卷 185-188页

作者： P.Shi F.T.cheng H.c.Man DepartmentofAppliedPhysics TheHongKongPolytechnicUniversityHongKongChina DepartmentofIndustrialandSystemsEngineering TheHongKongPolytechnicUniversityHongKongChina

NiTi samples were hydrothermally treated in NaOH at 200℃ with different soaking times. The morphology of the surface layer formed was studied by scanning electron microscopy (SEM). The composition of the layer and the major phases present were determined by energy-dispersive spectroscopy (EDS) and X-ray diffractometry (XRD), respectively. In contrast to the results reported by some authors, the surface layer was essentially Ni(OH)2 instead of being TiO2. The electrochemical behavior of the samples was studied by electrochemical impedance spectroscopy (EIS) in 3.5% Nacl solution at 23℃, and analyzed using a simplified Randle circuit consisting of a resistance R and a capacitance c in parallel. After hydrothermal treatment, R was increased by a factor ranging from 1.5 to 5.0 times, depending on the treatment time. The value of R of all the samples became steady within a period of less than 15 h. Results of the present study indicate that alkaline treatment leads to the growth of an insulating layer on NiTi, but the method is not suitable for surface modification of NiTi implants due to the enhanced Ni content in the surface layer.

关键词： Hydrothermal treatment NiTi NaOH Resistance Electrochemical impedance spectroscopy

Sea Urchin Spines as a Model-System for Permeable,Light-Weight ceramics with Graceful Failure Behavior. Part I. Mechanical Behavior of Sea Urchin Spines under compression

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Journal of Bionic Engineering 2009年第4期6卷 203-213页

作者： V.Presser S.SchultheiB c.Berthold K.GNickel Institute

The spines of pencil and lance urchins Heterocentrotus mammillatus and Phyllacanthus imperialis were studied as a model of light-weight material with high impact *** complex and variable skeleton construction ('stereom') of body and spines of sea urchins consists of highly porous Mg-bearing calcium *** basically brittle material with pronounced single-crystal cleavage does not fracture by spontaneous catastrophic device failure but by graceful failure over the range of tens of millimeter of bulk compression *** was observed in bulk compression tests and blunt indentation experiments on regular,infiltrated and latex coated sea urchin spine *** characterization was carried out using X-ray computer tomography,optical and scanning electron *** behavior is interpreted to result from the hierarchic structure of sea urchin spines from the rnacroscale down to the *** derived from this study see ceramics with layered porosity as a possible biomimetic construction for appropriate applications.

关键词： sea urchin urchin spines biominmitic mechanical behavior compression calcite

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Short exposure to paclitaxel induces multipolar spindle formation and aneuploidy through promotion of acentrosomal pole assembly

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Science china(Life Sciences) 2010年第11期53卷 1322-1329页

作者： BIAN MingLei1, FU JingYan1, YAN Yan1, cHEN Qiang1, YANG chao2, SHI QingHua2,JIANG Qing1 & ZHANG chuanMao1 1MOE Key Laboratory of cell Proliferation and Differentiation and the State Key Laboratory of Bio-membrane and Membrane Bio-engineering, college of Life Sciences, Peking University, Beijing 100871, china 2Hefei National Laboratory for Physical Sciences at Microscale and School of Life Sciences, University of Science and Technology of china, Hefei 230026, china MOE Key Laboratory of cell Proliferation and Differentiation and the State Key Laboratory of Bio-membrane and Membrane Bio-engineering College of Life Sciences Peking University Beijing China Hefei National Laboratory for Physical Sciences at Microscale and School of Life Sciences University of Science and Technology of China Hefei China

Paclitaxel is a widely used microtubule drug and cancer medicine. Here we report that by short exposure to paclitaxel at a low dose, multipolar spindles were induced in mitotic cells without centrosome amplification. Both TPX2 depletion and Aurora-A overexpression antagonized the multipolarity. Live cell imaging showed that some paclitaxel-treated cells accomplished multipolar cell division and a portion of the daughter cells went on to the next round of mitosis. The surviving cells grew into clones with varied genome content. The results indicated that an aneuploidy population could be induced by short exposure to paclitaxel at a low dose, implicating potential side effects of paclitaxel.

关键词： paclitaxel tpx2 Aurora-A multipolar cell division aneuploidy