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Two Dimensional Density FlUCtuation Measurements During the Non-Inductive Current Ramp-up Phase in the Compact Plasma wall Interaction Experimental Device CPD

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Plasma Science and Technology 2009年第4期11卷 397-401页

作者： H.ZUSHI T.RYOUkAI k.kIkUkAwA T.MORISAkI R.BHATTACHARYAY T.YOSHINAGA k.HANADA T.SAkIMURA H.IDEI k.DONO N.NISHINO H.HONMA S.TASHIMA T.MUTOH S.kUBO k.NAGASAkI M.SAkAMOTO Y.NAkASHIMA Y.HIGASHIZONO k.N.SATO k.NAkAMURA M.HASEGAwA S.kAwASAkI H.NAkASHIMA A.HIGASHIJIMA RIAM Kyushu University IGSES Kyushu University National Institute for Fusion Science Hiroshima University kyoto University University of Tsukuba

Two-dimensional structure of density fluctuations is examined during the current jump phase, indicating a change from the open magnetic fields to the closed ones. During the smooth current ramp-up phase the two-dimensional contour of the LiI intensity shows vertically alignment, consistent with the magnetic surfaces. At the inflection point in Ip ramp-up the LiI intensity contour becomes flat in the observation regime and then suddenly a steep gradient and higher intensity regime are formed in the vertical direction. This higher intensity corresponds to a burst of LiI waveform. According to these changes in the contour, it is found that, within ~1 ms around the burst of LiI, a low frequency coherent wave with a long wavelength rapidly grows. The relations with other signals （magnetic flux and microwave stray power） are discussed with respect to the topological change in the magnetic configuration and mode conversion of the incident electromagnetic waves.

关键词： Li sheet beam density fluctuations current ramp-up spherical tokamak

Seepage behavior of soil mixed with randomly distributed recycled plastic materials

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water Science and Engineering 2022年第3期15卷 257-264页

作者： V.P.Devipriya S.Chandrakaran k.Rangaswamy Department of Civil Engineering National Institute of Technology CalicutCalicut 673601India

Seepage through embankment fill materials is crucial issue in the construction of embankments for irrigation and drainage *** ground improvement methods should be used to improve the strength and stability characteristics of soil used as fill *** of waste plastic materials to enhance the engineering properties of soil is a sustainable ***,the use of raw products directly from plastic recycling units in the form of flakes and pellets as soil additives has the potential to further enhance the economic benefits of this *** study randomly mixed plastic materials with soil for use in the construction of earth embankments,such as river levees,dykes,and canal diversion structures,and evaluated the effectiveness of these materials in reducing seepage failures in hydraulic *** achieve these goals,this study collected high-density polyethylene(HDPE)plastic from plastic recycling units and used soil mixed with HDPE plastic in the form of flakes and pellets in different contents as embankment fill materials,then evaluated how these materials affected the piping *** experiments were conducted to determine the seepage velocity and critical hydraulic gradient of soil mixed with plastics in various contents and to compare the values with those of plain *** results showed that random distribution of waste plastics in the form of flakes and pellets in soil is an effective method for improving the piping resistance of soil.

关键词： Earth embankments Seepage Recycled plastics Critical hydraulic gradient Piping resistance

Provenance bias between detrital zircons from sandstones and river sands:A quantification approach using 3-D grain shape,composition and age

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Geoscience Frontiers 2020年第3期11卷 835-842页

作者： V.Markwitz C.L.kirkland k.Gessner School of Earth Sciences The University of Western AustraliaWA6009Australia School of Earth and Planetary Science Centre for Exploration Targeting-Curtin NodeCurtin UniversityWA6045Australia Geological Survey of western Australia 100 Plain StreetEast PerthWA6004Australia

Preservation bias may significantly impact the application of detrital zircon geochronology in reconstructing Earth surface *** we compare detrital zircons from the actively eroding Murchison River channel in western Australia with Ordovician fluvial sediments that have drained similar source rocks along the western margin of the west Australian *** addition to standard analysis of detrital zircon age spectra we apply multivariate statistics to test the relation between 3-D grain shape,U-content and U-Pb ages,with the objective to quantify differences between both sample groups and track preservation along the transport pathway of the Murchison *** results show that zircon grains in modern river sands display an upstream trend toward larger surface areas,volume equivalent diameters and grain widths,as well as toward higher U-contents and lower apparent grain densities.3-D grain shape,size and age spectra of Murchison River zircons evolve consistently downstream,but even at the river outlet remain distinct from the Ordovician samples,as a less mature representation of *** interpret Ordovician river zircons to represent a significantly depleted subset from which up to 22% of the zircon population may have been lost compared to the actively transported detrital *** discrepancy between the characteristics of detrital zircons in modern active rivers and ancient fluvial Ordovician sandstones demonstrates a bias that could be relevant for other source-sink detrital transport systems throughout Earth history.

关键词： X-ray tomography Detrital Zircon Grain shape Preservation Fluvial

Restorating marine coastal ecosystem health as a new goad for integrated catchment management in Tolo Harbour,Hong kong,China

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Chinese Journal of Population,Resources and Environment 2004年第2期2卷 11-19页

作者： Lam k.C. Department of Geography and Resoure management The Chinese University of Hong Kong.ShatinNew TerritoriesHong KongChinahe paper demonstrates why it is necessary to take the restoration of marine coastal ecosystem health as a new goal for integrated catchment management in coastal area of the Tolo Harbour. The present goal of integrated catchment management (ICM) in the Tolo Harbour is to meet with Water Quality Objectives. The performance of an ICM plan Tolo Harbour Action Plan (THAP) is evaluated by using marine coastal ecosystem health indicators including stress indicators and responses indicators. Since the implementation of THAP in 1988 some significant reduction in pollution loading has been observed - reduction of 83 % of BOD load and 82 % of TN between 1988 and 1999. There has been an improvement in the health state of Tolo Harbour marine coastal ecosystem as evidenced in the trends of the physical chemical and biological indicators although some reverse fluctuations in some periods exist. However this can only be considered as the first sign of the ecosystem health restoration since ecosystem health covers not only physical chemical and biological aspects of an ecosystem but also ecosystem-service-function aspect. It is recommended to take the restoration and protection of marine coastal ecosystem health as a new goal instead of water quality objective management for integrated catchment management in Tolo Harbour catchment. Steps to further improve the marine coastal ecosystem health of Tolo harbour are discussed in the paper.

The paper demonstrates why it is necessary to take the restoration of marine coastal ecosystem health as a new goal for integrated catchment management, in coastal area of the Tolo Harbour. The present goal of integrated catchment management (ICM) in the Tolo Harbour is to meet with water Quality Objectives. The performance of an ICM plan, Tolo Harbour Action Plan (THAP), is evaluated by using marine coastal ecosystem health indicators including stress indicators and responses indicators. Since the implementation of THAP in 1988, some significant reduction in pollution loading has been observed - reduction of 83 % of BOD load and 82 % of TN between 1988 and 1999. There has been an improvement in the health state of Tolo Harbour marine coastal ecosystem as evidenced in the trends of the physical, chemical and biological indicators, although some reverse fluctuations in some periods exist. However, this can only be considered as the first sign of the ecosystem health restoration, since ecosystem health

关键词： Marine coastal ecosystem health integrated catchment management pollution loading indicator Tolo Harbour Action Plan.

Effect of texture and twinning on mechanical properties and corrosion behavior of an extruded biodegradable Mg-4Zn alloy

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Journal of Magnesium and Alloys 2019年第4期7卷 707-716页

作者： M.Sabbaghian R.Mahmudi k.S.Shin School of Metallurgical and Materials Engineering College of EngineeringUniversity of TehranTehran 14395-515Iran Magnesium Technology Innovation Center School of Materials Science and EngineeringSeoul National University1 Gwanak-roGwanak-guSeoul 08826Republic of Kore

Microstructure,texture,mechanical properties and corrosion behavior of the extruded Mg-4Zn alloy,as a biodegradable material,were investigated.A refined microstructure caused by dynamic recrystallization(DRX),and a general fiber texture were achieved after *** properties along different directions of the extruded samples were investigated using shear punch test(SPT).The shear yield stress(SYS)of 113.8 MPa obtained in the transverse direction(TD)was higher than the 106 MPa achieved for the extruded direction(ED)and 45˚*** was attributed to the higher amounts of twins and also lower Schmid factor(SF)in the *** the other hand,encouraged activation of the basal slip system in the 45˚samples resulted in improved room temperature formability,as indicated by the normalized displacement in the SPT *** back scattered diffraction(EBSD)analysis of the surfaces corroded in the phosphate buffered saline(PBS)solution,showed that despite having similar grain sizes and second phase particles shape and volume fractions,surfaces containing grains near(0001)orientations and extension twins(TD and 45˚samples)have lower corrosion rates,as compared to the ED specimens.

关键词： Mg-Zn alloy Corrosion rate Dynamic recrystallization Texture Twinning

Structural Analysis for Qazzaz Metamorphic Core Complex,Northwestern Arabian Shield,Saudi Arabia

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Acta Geologica Sinica(English Edition) 2024年第5期98卷 1187-1201页

作者： Mansour H.AL-HASHIM Osama M.k.kASSEM Department of Geology and Geophysics College of ScienceKing Saud University11451 RiyadhSaudi Arabia Department of Geology National Research CenterCairoEgypt

Identifying deformational mechanisms and associated structures at various scales,ranging from regional-scale structures to microscopic fabric,is crucial for the assessment of tectonic ***-three samples were taken from the Qazzaz metamorphic core complex to estimate the finite strain for felsic and mafic *** samples included gneisses rocks,monzogranite,and metavolcano-sedimentary rocks for both the Thalbah and Bayda *** the Rf/j and Fry methods,the axial ratios(XZ)range about 2.20 to 7.10 and 1.90 to 9.10,*** various rock units,the strain measurements show moderate to highly *** of the observed samples show shallow wNw dipping along a N to wNw trend of finite strain(X).The short axes(Z)based to be subvertical foliation related with a subhorizontal *** results demonstrate that contacts generated at semi-brittle to ductile deformation and that the strain of magnitude has the same value for different lithologic *** concluded that nappe generation in orogens results from pure shear deformation.

关键词： Finite strain metamorphic core complex Qazzaz area Saudi Arabia

Pathways of nanotoxicity:Modes of detection,impact,and challenges

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Frontiers of Materials Science 2021年第4期15卷 512-542页

作者： Deepshikha GUPTA Parul YADAV Devesh GARG Tejendra k.GUPTA Amity Institute of Applied Sciences Amity University Uttar PradeshNoida 201301India

Nanotoxicology has become the subject of intense research for more than two *** of articles have been published but the space in understanding the nanotoxicity mechanism and the assessment is still *** researches clearly show potential benefits of nanomaterials(NMs)in diagnostics and treatment,targeted drug delivery,and tissue engineering owing to their excellent physicochemical ***,these NMs display hazardous health effect then to the greater part of the materials because of small size,large surface area-to-volume ratio,quantum size effects,and environmental ***,a large number of NMs are used in industrial products including several medical applications,consumer,and healthcare ***,they came into the environment without any safety *** measurement of toxicity level has become important because of increasing toxic effects on living *** realistic mechanism-based strategies are still needed to determine the toxic effects of *** the assessment of NMs toxicity,reliable and standardized procedures are *** review article provides systematic studies on toxicity of NMs involving manufacturing,environmental factors,eco-toxic and genotoxic effects,some parameters which have been ignored of NMs versus their biological counterparts,cell heterogeneity,and their current challenges and future perspectives.

关键词： nanomaterial nanotoxicity cytotoxicity,genotoxicity in-vivo and in-vitro toxicity reactive oxygen species

Population structures and spatial patterns of two unpalatable Arisaema species(Araceae) with and without clonal reproduction in a riparian forest intensively grazed by Sika deer

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Journal of Forestry Research 2020年第1期31卷 155-162页

作者： Tetsuya k.Matsumoto Muneto Hirob Yasuaki Akaji Yuko Miyazaki Graduate School of Environmental and Life Science Okayama UniversityTsushima-Naka 1-1-1Kita-kuOkayama 700-8530Japan Present Address:Center for Environmental Biology and Ecosystem Studies National Institute for Environmental StudiesOnogawa 16-2Tsukuba 305-8506Japan

General decline of understory cover can result from increased abundance of and foraging pressure by *** population size and degree of aggregation can increase for unpalatable understory plants that escape foraging *** reproduction can enable unpalatable plant species to increase their population sizes while trending toward spatially aggregated ***,the details of the relationship between clonal reproduction in unpalatable plants and their dynamics under intensive deer herbivory are not *** compared the population structures and spatial patterns of two coexisting unpalatable plant species,Arisaema ovale(with clonal reproduction)and ***(without clonal reproduction)in a riparian forest intensively grazed by Sika deer,and examined the null hypothesis that the extent of spatial aggregation and local population size would not differ between the clonal and non-clonal Arisaema *** a 0.36-ha plot,*** had a larger population size(1087 individuals)with a higher abundance ratio of small plants(pwed that both populations were spatially aggregated(pwever,became weaker than that of ***,when we excluded one dense patch originating from irregular seed *** results,excluding the aggregated distribution observed in ***,suggested a substantial contribution of clonal reproduction to the expansion of the local *** population following intensive grazing by Sika deer.

关键词： Arisaema ovale Arisaema peninsulae Deer herbivory Spatial pattern Unpalatable plant

Safe formation control of multiple unmanned aerial vehicles:control design and safety-stability analysis

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Control Theory and Technology 2024年第3期22卷 442-454页

作者： Haoqi Li Jiangping Hu Qingrui Zhou Bijoy k.Ghosh School of Automation Engineering University of Electronic Science and Technology of ChinaChengdu 611731SichuanChina Yangtze Delta Region Institute(Huzhou) University of Electronic Science and Technology of ChinaHuzhou 313000ZhejiangChina Qian Xuesen Laboratory of Space Technology China Academy of Space TechnologyBeijing 100094China Department of Mathematics and Statistics Texas Tech UniversityLubbockTX 79409-1042USA

Both safety and stability are primary performance criteria for multi-unmanned aerial vehicle(multi-UAV)systems in many coordination *** approaches often consider safety and stability *** is necessary and urgent to develop a safety-stability control strategy to merge these two performance *** this paper,a unified approach is developed to consider safety and stability for multi-UAV formation *** stability criterion is represented by a Lyapunov function and safety criterion is represented by a barrier function and then a relaxed converse control Lyapunov-barrier theorem is *** the help of a relaxed converse control Lyapunov-barrier function(RCCLBF),a distributed safety-stability formation control strategy is proposed for the multi-UAV *** transforming the solution of RCCLBF to a Lyapunovlike stabilization problem,we show that the proposed formation control strategy can drive the UAVs staying within a specified safe *** results are provided to validate the proposed safety-stability formation control strategy.

关键词： Multi-UAV system Formation control Lyapunov function Barrier function Stability with safety guarantee