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Using high-resolution aerial images to study gully development at the regional scale in southern China

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International Soil and Water Conservation Research 2020年第2期8卷 173-184页

作者： Honghu Liu georg Hormann Bingyu Qi Qiuxing Yue State Key Lab Soil Erosion and Dryland Farming on the Loess Plateau Institute of Soil and Water ConservationChinese Academy of Sciences and Ministry of Water ResourcesXinong Rd 26712100YanglingShaanxi ProvincePR China Changjiang River Scientific Research Institute Changjiang Water Resource CommissionNo 23 Huangpuda Street430010WuhanHubei provincePR China Department of Hydrology and Water Resources Management Institute of Natural Resource ConservationKiel UniversityOlshausenstr.75D-24098 KielGermany

There are 239,100 gullies in southern China,which cause the degradation of ecological ***,studies on gully development at the regional scale is relatively *** purpose of this study is to analyze the regional gully dynamics and explore how land use and topographic factors affect gully *** data consists of land use maps derived from high-resolution images from 2004 to 2014,and topography maps from a digital elevation model with a pixel size of 8 m×8 m in two 25-km2 study sites of Anxi(AX)and Xingning county(XN).The following results were obtained:(1)AX gullies decreased from 2006 to 2014 while XN first increased from 2004 to 2009,and then decreased from 2009 to *** AX and XN gully area in percentage of the total area ranged from 1%to 3%,which was higher than the average 0.25%of the whole southern China by the artificial survey in 2005.(2)Most of AX and XN gullies occurred along the ridgeline and had the close relationships with the upstream contributing area and slope gradient.(3)New gullies developed on the exposed land and *** lost gullies were converted into forestland and *** fact,most of these gullies were only covered by vegetation,not real *** results proved that gully decreased,but construction of roads and buildings intensified gully ***,these findings reveal that vegetation protection and ecological restoration should be adopted in southern China.

关键词： Digital elevation model Slope gradient Exposed lands Upstream contributing area

Global Energy Interconnection: A building block towards planetary stewardship

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Global Energy Interconnection 2019年第2期2卷 95-97页

作者： georg Kell United Nations Global Compact Arabesque GEIDCO Arabesque Asset Management Ltd

Climate change is no longer a distant threat. Its implications are already being felt around the globe in the form of heat waves [1], extreme weather, rising sea levels and a broad destruction of the natural environment. Global temperatures have been rising since the start of the industrial revolution. Today, they are 1.1 degrees Celsius above pre-industrialization. Many scientists fear that we are well on track to add another 2 to 3 degrees in the coming decades. At the Paris Climate Summit in 2015, governments vowed to keep the rise of global temperatures well below 2 degrees Celsius. Yet, despite this pledge, the globe continues to warm up. According to the International Energy Agency, global energy-related CO2 emissions grew by 1.4% to a record of 32.5 giga tons in 2017 [2]. In South East Asia alone, over 300 new coal-fired power plants are under construction or planning [3].

关键词： Climate change weather

Seed production,seed dispersal and seedling establishment of two afromontane tree species in and around a church forest：implications for forest restoration

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Forest Ecosystems 2016年第4期3卷 287-296页

作者： Abrham Abiyu Demel Teketay Gerhard Glatzel georg Gratzer Amhara Agricultural Research Institute P. O. Box 527 Bahir Dar Ethiopia Department of Crop Science and Production Botswana University of Agriculture and Natural Resources Private Bag 0027 Gaborone Botswana Institute of Forest Ecology University of Natural Resources and Life Sciences Peter Jordan Strage 82 A-1190 Vienna Austria

Background：Seed production,seed dispersal and seedling establishment are relevant life phases of *** these processes and their patterns is essential to recognize vegetation dynamics and to apply it to forest ***：For Olea europaea and Schefflera abyssinica,fecundity was estimated using randomized branch *** dispersal and seedling establishment were monitored using spatially explicit seed traps and *** functions were calibrated applying inverse ***：*** produced more seeds and had longer dispersal distances compared to *** between observed and predicted number of recruits were statistically *** of the two species showed different niche ***：The studied species were recruitment-limited due to low dispersal activity or lack of suitable *** relying on natural regeneration should overcome these limitations by increasing disperser visitation and reducing biotic and abiotic stresses.

关键词： Fecundity Olea europaea Schefflera abyssinica Recruitment limitation Restoration

ADAPTIVITY IN SPACE AND TIME FOR MAGNETOQUASISTATICS

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Journal of Computational Mathematics 2009年第5期27卷 642-656页

作者： Markus Clemens Jens Lang Delia Teleaga georg Wimmer Helmut-Schmidt-Universitat Hamburg Holstenhofweg 8522043 HamburgGermany Technische Universitat Darmstadt Schlossgartenstraβe 764289 DarmstadtGermany

This paper addresses fully space-time adaptive magnetic field computations. We describe an adaptive Whitney finite element method for solving the magnetoquasistatic formulation of Maxwell＇s equations on unstructured 3D tetrahedral grids. Spatial mesh re- finement and coarsening are based on hierarchical error estimators especially designed for combining tetrahedral H（curl）-conforming edge elements in space with linearly implicit Rosenbrock methods in time. An embedding technique is applied to get efficiency in time through variable time steps. Finally, we present numerical results for the magnetic recording write head benchmark problem proposed by the Storage Research Consortium in Japan.

关键词： Magnetoquasistatics Space-time adaptivity Edge elements Rosenbrock meth-ods Hierarchical error estimator SRC benchmark problem.

Applications of membrane systems in distributed systems

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Progress in Natural Science:Materials International 2007年第4期17卷 401-410页

作者： Aneta Binder Rudolf Freund georg Lojka Marion Oswald Institute of Computer Languages Vienna University of TechnologyFavoritenstr. 9WienAustria

Based on the biological model of cell-to-cell communication proposed by A. Rustom et al. (Science, 2004, 303: 1007-1010), we investigate the possibilities to apply P systems with dynamic channels transporting membrane... 详细信息

关键词： membrane system P system communication process.

Study of the degradation behavior and the biocompatibility of Mg-0.8Ca alloy for orthopedic implant applications

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Journal of Magnesium and Alloys 2019年第2期7卷 249-257页

作者： Aya Mohamed Ahmed MEl-Aziz Hans-georg Breitinger Materials Engineering Department German University in Cairo(GUC)11835 New CairoEgypt Department of Biochemistry German University in Cairo(GUC)11835 New CairoEgypt

Mg-Ca alloys have recently attracted great attention towards the research in the field of orthopedic biodegradable *** study presents an in vitro degradation assessment of Mg-0.8Ca(0.8 wt.%of Ca)alloy in Hank’s balanced salt solution(HBSS).Immersion,hydrogen evolution and electrochemical behavior was studied as well as the cytotoxicity of the degradation *** and phase composition of the corrosion products were studied using SEM,EDX and XRD *** in HBSS resulted in the formation of the needle-shaped carbonated hydroxyapatite which was similar to the biological apatite in the human *** kinetics showed that Mg-0.8Ca alloy had approximately 3-fold faster degradation rate than the pure Mg(1.08±0.38 mm/year for Mg-0.8Ca and 0.35±0.17 mm/year for pure Mg),as observed in two independent ***,pure Mg and Mg-0.8Ca alloy were biocompatible,generating no cytotoxic degradation products against human-derived HEK 293 ***,the Mg-0.8Ca alloy was found to be a promising biodegradable implant in terms of bioactivity and compatibility with human cell *** on the application of the implant and the estimated healing time of the bone,the desired degradation rate of an implant can be controlled by the Mg-Ca composition of such alloys.

关键词： Mg-Ca alloys Biodegradability Orthopedic implants Biocompatibility Toxicity Hydroxyapatite

Experimental study on the tribo-chemical smoothening process between self-mated silicon carbide in a water-lubricated surfacecontact reciprocating test

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Friction 2019年第2期7卷 181-191页

作者： Le JIN Herbert SCHEERER georg ANDERSOHN Matthias OECHSNER Dieter HELLMANN Center for Structural Materials Technische Universit?t Darmstadt KSB

Silicon carbide(SiC) can be tribo-chemically smoothened during a self-mated sliding procedure in the aqueous environment. As well reported in the point-contact tests, this smoothening process works well due to the abundant water as oxidant. After this smoothening process, the tribo-surface is well polished, a closely mated tribo-gap naturally forms, and an ultra-low friction state is built. However, water in the tribo-gap could be insufficient in industrial applications, e.g., the seal gap in mechanical seals. In this study, the tribo-chemical smoothening behavior in such environment was researched. A surface-contact reciprocating test was used to simulate the aqueous environment where water was insufficient. After tests, compared to the published results from the point-contact tests, the same ultra-low friction state was achieved. A part of the tribo-surface was tribo-chemically smoothened. The obtained smoothened surface microstructure was consistent with the published information. Meanwhile, severe abrasive wear occurred. A porous oxygen-rich layer was found existing beneath the abrasion-induced grooves, in which numerous smashed wear debris adhered on the worn surfaces. We concluded that the shortage of water initiated the severe abrasion, meanwhile the generated wear debris aggravated the wear condition. This understanding is instructive for developing new methods to avoid the severe abrasion in the same water insufficient environment.

关键词： silicon carbide surface-contact sliding friction tribo-chemical smoothening abrasion ultra-low friction mechanical seal

Thermal transport and phase transitions of zirconia by on-the-fly machine-learned interatomic potentials

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npj Computational Materials 2021年第1期7卷 1426-1434页

作者： Carla Verdi Ferenc Karsai Peitao Liu Ryosuke Jinnouchi georg Kresse University of Vienna Faculty of PhysicsComputational Materials PhysicsKolingasse 14-161090 ViennaAustria VASP Software GmbH Sensengasse 81090 ViennaAustria Toyota Central R&D Labs. Inc.Aichi 480-1192Japan

Machine-learned interatomic potentials enable realistic finite temperature calculations of complex materials properties with firstprinciples *** is not yet clear,however,how accurately they describe anharmonic properties,which are crucial for predicting the lattice thermal conductivity and phase transitions in solids and,thus,shape their technological *** we employ a recently developed on-the-fly learning technique based on molecular dynamics and Bayesian inference in order to generate an interatomic potential capable to describe the thermodynamic properties of zirconia,an important transition metal *** machine-learned potential accurately captures the temperature-induced phase transitions below the melting *** further showcase the predictive power of the potential by calculating the heat transport on the basis of Green–Kubo theory,which allows to account for anharmonic effects to all *** study indicates that machine-learned potentials trained on the fly offer a routine solution for accurate and efficient simulations of the thermodynamic properties of a vast class of anharmonic materials.

关键词： materials transitions harmonic

Maize defense against insect herbivory:A novel role for 9-LOX-derived oxylipins

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Molecular Plant 2023年第10期16卷 1484-1486页

作者： Guillermo H.Jimenez-Aleman georg Jander Boyce Thompson Institute 533 Tower RoadIthacaNY 14853USA

Up to 40%of global crops are destroyed by arthropod pests,either prior to harvest or during storage(Gullino et al.,2021).This problem is exacerbated by current and anticipated climatechanges that will allow the long-term survival of pest populationsin new habitats,as well as by the introduction of new pest speciesinto areas where they were not previously *** instance,the recent introduction of Spodoptera frugiperda(fall armyworm),which previously was a major pest of Zea mays(maize)only in theAmericas,led to the expansion of this species throughout themaize-growing regions of Africa and Asia in less than 5 years(Tay et al.,2022).

关键词： crops destroyed instance