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Does forest restoration influence soil infiltrability? A case study in the restored woodland of Sierra de ávila(Central Spain)

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Journal of Mountain Science 2021年第7期18卷 1778-1793页

作者： MOnGIL-MAnSO Jorge nAVARRO-HEVIA Joaquín san MARTÍn Roberto Hydrology and Conservation Research Group Catholic University“Santa Teresa de Jesús”ofÁvilaÁvila 05005Spain Forest Water and Soil Research GroupPalencia 34004Spain Department of Agricultural and Forestry Engineering University of ValladolidPalencia 34004Spain Department of Statistics and Operations Research University of ValladolidPalencia 34004Spain

Infiltration,as a major component of the hydrological cycle,plays an important role in ecosystems,river flooding,and soil ***,this process has been studied on different soils,with different vegetation cover,and under different climate ***,it is still necessary to know how infiltration rates depend on land degradation,vegetation cover,forest management,and forest restoration,since soil infiltration is related to soil hydrological function and hydrological ecosystem *** aim of our study is to analyze the way reforestation and check dam construction have helped to improve soil infiltration rates in comparison with old,degraded land,different soils and vegetation covers in Central ***,three infiltration tests were carried out by means of a simple methacrylate infiltrometer ring,in four sampling plots,for five types of land use:(i) native holm oak forest,(ii) 60-year-old reforested pine wood,(iii) shrubs,(iv) sediment wedges of check dams,and(v) gullies and degraded *** results show much higher infiltration rates in the soil of 60-yearold pine reforestation sites(1198.00 mm·h^(-1)),and in the sediment wedges of check dams(1088.00 mm·h^(-1)),than in those of degraded hillslopes(365.00 mm·h^(-1)) and shrubland(420.80 mm·h^(-1)).The rates were also shown to be close to those from the remaining patches of native holm oak woodland(770.40 mm·h^(-1)).We also found that organic matter,humus and litter depth,and height of vegetation and cover,all improve soil infiltration rates,while slope degree,presence of coarse elements,stoniness,clay content,bulk density,and electric conductivity inhibit the *** was additionally seen that pine reforestation and check dam construction caused degraded land to recover its hydrological conditions to a level that is quite close to that of the ancient oak holm native forest,alongside ameliorating the hydrological cycle in the *** information will be very useful for decisi

关键词： Soil hydrology Permeability Runoff Reforestation Land restoration

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A review of the thermal stability of metastable austenite in steels:Martensite formation

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Journal of Materials Science & Technology 2021年第32期91卷 200-214页

作者： Yong Li David san Martín Jinliang Wang Chenchong Wang Wei Xu State key laboratory of rolling and automation Northeastern UniversityShenyang 110819China Materalia Research Group Centro Nacional de Investigaciones Metalúrgicas(CENIM-CSIC)Avda Gregorio del Amo 8Madrid E-28040Spain School of Mechanical and Power Engineering Guangdong Ocean UniversityZhanjiang 524088China

Metastable austenite plays a critical role in achieving improved combinations of high strength and high ductility/toughness in the design of advanced high-strength steels(AHSS). The thermal stability of metastable austenite determines the transformation characteristics of AHSS and thus primarily determines the microstructure evolution during complex processes, e.g., the quenching and partitioning process, to achieve the desirable microstructure. This study provides a review of the thermal stability of austenite and its influence on martensitic transformation from both experimental and theoretical modeling perspectives. From the experimental perspective, factors affecting the thermal stability are analyzed,the relative sensitivities are compared, and their corresponding mechanisms are discussed. From the theoretical modeling perspective, the most representative kinetic models that describe athermal and isothermal martensitic transformation are reviewed. The advantages, shortcomings, and applicability of each model are discussed. The systematic review of both experimental and theoretical aspects reveals critical factors in tailoring the stability of metastable austenite and, therefore, provides guidance for the design of advanced steels.

关键词： Austenite Thermal stability Martensitic transformation Kinetic models

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Evaluation of effectiveness of polymer coatings in reducing blastinduced deformation of steel plates

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Defence Technology（防务技术） 2021年第6期17卷 1895-1904页

作者： Damith Mohotti P.L.n.Fernando Dakshitha Weerasinghe alex Remennikov School of Engineering and Information Technology The University of New South WalesCanberraACT2600Australia Department of Civil Engineering Faculty of EngineeringGeneral Sir John Kotelawala Defence UniversityRatmalanaSri Lanka School of Civil Engineering Faculty of EngineeringThe University of SydneyDarlingtonNSW2006Australia Centre for Infrastructure Protection and Mining Safety University of WollongongWollongongNSW2522Australia

Incorporating elastomers such as polymers in protective structures to withstand high energetic dynamic loads,has gained significant *** main objective of this study is to investigate the influence of a Polyurea coating towards the blast-induced response in steel *** such,Polyurea coated steel plates were tested under near-field blast loads,produced by the detonation of 1 kg of spherical nitromethane charges,at a standoff distance of 150 *** steel(XLERPLATE 350)and high-strength steel(BIS80)plates with thicknesses of 10 mm were Polyurea coated with thicknesses of 6 mm and 12 mm on either the front(facing the charge)or the back *** deformation profiles were measured using 3D *** simulations were performed using the non-linear finite element code *** strain-dependent behaviour of the steel and Polyurea were represented by Johnson-cook and Money-Rivlin constitutive models,*** numerical models were validated by comparing the plate deflection results obtained from the experiments and were then used in the subsequent parametric study to investigate the optimum thickness of the Polyurea *** results indicate that back face coating contributes towards an approximately 20%reduction in the residual deformation as well as the absence of melting of the Polyurea layer,while the front-face coating can be used a means of providing additional standoff distance to the steel plates.

关键词： Polyurea coating near-field blast LS-DYnA Plate deformation ALE

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A Review on Primary and Secondary Controls of Inverter-interfaced Microgrid

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Journal of Modern Power Systems and Clean Energy 2021年第5期9卷 969-985页

作者： Kafeel Ahmed Mehdi Seyedmahmoudian Saad Mekhilef n.M.Mubarak alex Stojcevski School of Software and Electrical Engineering Swinburne University of TechnologyVIC 3122VictoriaAustralia Power Electronics and Renewable Energy Research Laboratory Department of Electrical EngineeringUniversity of Malaya50603 Kuala LumpurMalaysia Department of Chemical Engineering Faculty of Engineering and ScienceCurtin University of Technology98009 SarawakMalaysia

The demand of electricity and environmental issues associated with conventional power generation plants are increasing *** technology has transformed the conventional power system through the integration of distributed generation(DG).With the help of modern power electronic technology,the conventional power system is able to support the integration of DGs based on renewable energy sources(RESs).The systematic combination of DGs with energy storage system forms a microgrid(MG),which can operate in islanded mode or grid-connected *** intermittent nature of RES and varying load pose substantial obstacles such as voltage and frequency instability,and the unreliability of *** feeder impedances and non-linear loads are considered as present challenges in MG *** control has been useful in undertaking solutions to these *** paper covers the deep insight of different control methods applied at the primary and secondary control levels in hierarchical *** primary control,the classification based on droop and non-droop controls is *** virtual synchronization machine(VSM)based control method is *** and frequency restoration control and economical operations at decentralized and centralized secondary control are analyzed in *** on the existing literature,critical discussion on MG control and future trends are also presented to provide future research perspectives.

关键词： Distributed generation(DG) hierarchical control droop control non-droop control inverter

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Long-term open circuit microbial electrosynthesis system promotes methanogenesis

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Journal of Energy Chemistry 2020年第2期29卷 3-6页

作者： Raúl Mateos Adrián Escapa María Isabel san-Martín Heleen De Wever Ana Sotres Deepak Pant Chemical and Environmental Bioprocess Engineering Group Natural Resources Institute(IRENA)University of LeonLeon 24071Spain Department of Electrical Engineering and Automatic Systems Universidad de LeonLeon 24071Spain Reparation and Conversion Technology Flemish Institute for Technological Research(VITO)Mol 2400Belgium

Microbial electrosynthesis(MES) can potentially provide a mean for storing renewable energy surpluses as chemical energy. However, the fluctuating nature of these energy sources may represent a threat to MES, as the microbial communities that develop on the biocathode rely on the continuous existence of a polarized electrode. This work assesses how MES performance, product generation and microbial community evolution are affected by a long-period(6 weeks) power off(open circuit). Acetogenic and H2-producing bacteria activity recovered after reconnection. However, few days later syntrophic acetate oxidation bacteria and H2-consuming methanogens became dominant, producing CH4 as the main product, via electromethanogenesis and the syntrophic interaction between eubacterial and archaeal communities which consume both the acetic acid and the hydrogen present in the cathode environment. Thus,the system proved to be resilient to a long-term power interruption in terms of electroactivity. At the same time, these results demonstrated that the system could be extensively affected in both end product generation and microbial communities.

关键词： Biocathode Electromethanogenesis Microbial electrosynthesis Microbial community dynamics Methanogens Acetogens

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MULTIPLE POSITIVE SOLUTIOnS FOR QUASILInEAR ELLIPTIC PROBLEMS InVOLVInG COnCAVE-COnVEX nOnLInEARITIES AnD MULTIPLE HARDY-TYPE TERMS

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Acta Mathematica Scientia 2013年第5期33卷 1314-1328页

作者： Tsing-san HSU Center for General Education Chang Gung University

In this paper, we deal with the existence and multiplicity of positive solutions for the quasilinear elliptic problem -△pu-∑i=1^kμi｜u｜^p-2/｜x-ai｜p^u=｜u｜^p^＊-2u＋λ｜u｜^q-2u,x∈Ω,where Ω belong to R^n（n ≥ 3） is a smooth bounded domain such that the different points ai∈Ω,i= 1,2,...,k,0≤μi〈μ^-=（n-p/p）^p,λ〉0,1≤q〈p,and p^＊=p^n/*** results depend crucially cn the parameters λ,q and μi for i=1,2,...,k.

关键词： multiple positive solutions concave-convex nonlinearities multiple Hardy- type terms

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On the Asymptotic Uniformity of the Quantization Error for Moran Measures on R^1

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Acta Mathematica Sinica,English Series 2019年第9期35卷 1520-1540页

作者： san Guo ZHU School of Mathematics and Physics Jiangsu University of Technology

Let E be a Moran set on R1 associated with a bounded closed interval J and two sequences(nk)k =1 ^∞ and(Ck =(ck,j)j=1)^nk)k≥1. Let μ be the Moran measure on E associated with a sequence(Pk)k≥1 of positive probability vectors with Pk =(pk,j)j =1,^nk, k ≥ 1. We assume that k≥1 1≤j≤nk^inf min Ck,j>0,k≥1 1≤j≤nk^inf minCk,j>0,k≥1 1≤j≤nk ^inf min pk,j>0. For every n ≥ 1, let αn be αn n optimal set in the quantization for μ of order r ∈(0,∞) and{Pa(αn)}a∈α∈an an arbitrary Voronoi partition with respect to αn. We write Iα(α,μ):=∫Pα(αn)^d(x,αn)^τ dμ(x),α∈αn;J(αn,μ):=α∈αn^minⅠα(α,μ),J(αn,μ):=α∈αn^max Ⅰα(α,μ).We show that J(αn,μ),J(αn,μ) and en^r,r(μ)-en^r +1,r(μ) are of the same order as 1/n en^r ,r(μ), where en^r ,r(μ):=∫d(x,αn)^r dμ(x) is the nth quantization error for μ of order r. In particular, for the class of Moran measures on R1, our result shows that a weaker version of Gersho’s conjecture holds.

关键词： Moran measures quantization error Voronoi partition asymptotic uniformity

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Climate,female traits and population features as drivers of breeding timing in Mediterranean red deer populations

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Integrative Zoology 2017年第5期12卷 396-408页

作者： Marta PELÁEZ Alfonso san MIGUEL Carlos RODRÍGUEZ-VIGAL Ramón PEREA Department of natural Systems and Resources Technical University of MadridMadridSpain national Parks Autonomous Agency MadridSpain Department of Biology Stanford UniversityStanfordCaliforniaUSA

Understanding the factors that lead to variation in the timing of breeding in widespread species such as red deer(Cervus elaphus)is crucial to predict possible responses of wild populations to different climate ***,we sought to further understand the causes of inter-annual variation in the reproduction timing of female deer in Mediterranean *** integrative approach was used to identify the relative importance of individual,population and climate traits in the date of conception of free-ranging deer,based on a dataset of 829 hinds culled during 12 *** found that a population trait,density,was the most important factor explaining the variation in conception dates,with greater densities causing later conception *** mass was the second in importance,with heavier females conceiving earlier than lighter *** equally important was the spring real bioclimatic index,a measure of plant productivity,causing later conception dates in the least productive springs(drier and hotter).Another climatic component,the end of summer drought,showed that the sooner the autumn arrives(greater rainfalls and cooler temperatures)the earlier the conception ***,age class was found to be a minor factor in determining conception *** older females(≥10 years old)conceived significantly later,suggesting reproductive *** study highlights not only the importance of population and individual traits but also the influence of climatic parameters on the deer reproductive cycle in Mediterranean environments,giving valuable insight into how reproductive phenology may respond to seasonality and global climate changes.

关键词： density-dependence mating short-day breeder summer drought ungulates

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All-atom Molecular Dynamic Simulations and nMR Spectra Study on Intermolecular Interactions of n,n-dimethylacetamide-Water System

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Chinese Journal of Chemical Physics 2008年第3期21卷 221-226页

作者： Rong Zhang Zai-you Tan san-lai Luo Lab of Physical Chemistry College of Pharmacy Guangdong Pharmaceutical University Guangzhou510006 China

n,n-dimethylacetamide （DMA） has been investigated extensively in studying models of peptide bonds. An all-atom MD simulation and the nMR spectra were performed to investigate the interactions in the DMA- water system. The radial distribution functions （RDFs） and the hydrogen-bonding network were used in MD simulations. There are strong hydrogen bonds and weak C-H…O contacts in the mixtures, as shown by the analysis of the RDFs. The insight structures in the DMA-water mixtures can be classified into different regions by the analysis of the hydrogen-bonding network. Chemical shifts of the hydrogen atom of water molecule with concentration and temperatures are adopted to study the interactions in the mixtures. The results of nMR spectra show good agreement with the statistical results of hydrogen bonds in MD simulations.

关键词： All-atom simulation nMR spectrum DMA-water system Hydrogen bond

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Multiple solutions for weighted nonlinear elliptic system involving critical exponents

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Science China Mathematics 2015年第1期58卷 161-178页

作者： nYAMORADI nemat HSU Tsing san Department of Mathematics Faculty of Sciences Razi University Department of natural Sciences in the Center for General Education Chang Gung University

In this paper, by using the idea of category, we investigate how the shape of the graph of h（x） affects the number of positive solutions to the following weighted nonlinear elliptic system： = （ n-2-2a 2. where 0 is a smooth bounded domain in ]1n （n 〉 3）, A, cr 〉 0 are parameters, 0 ≤ μ 〈 μa a 2 ＇ h（x）, KI（X） and K2（x） are positive continuous functions in , 1 〈 q 〈 2, a, β 〉 1 and a ＋ β = 2＊（a,b）（2＊（a, b） 2n = n-2（1＋a-b） is critical Sobolev-Hardy exponent）. We prove that the system has at least k nontrivial nonnegative solutions when the pair of the parameters （）, r） belongs to a certain subset of n2.

关键词： Caffarelli-Kohn-nirenberg inequality variational method critical Hardy-Sobolev exponent mul-tiple positive solutions

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