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Soil Microbial Population in the Vicinity of the Bean Caper(Zygophyllum dumosum)Root Zone in a Desert System

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Pedosphere 2007年第6期17卷 758-765页

作者： i.SHMUELi g.BARNESS Y.STEiNBERgER The Mina & Everard goodman Faculty of Life Sciences Bar-ilan University Ramat-Gan 52900(Israel)

The aim of the current study was to g.i. a better understanding of the changes in soil microbial biomass and basal respiration dynamics in the vicinity of the bean caper （Zygophyllura duraosura） perennial desert shrub and the inter-shrub sites. Microbial biomasses as well as basal respiration were found to be sig.i.icantly greater in the soil samples taken beneath the Z. duraosura shrubs than from the inter-shrub sampling sites, with no differences between the two sampling layers （0-10 and 10-20 cm） throughout the study period. However, seasonal changes were observed due to autumn dew formation, which sig.i.icantly affected microbial biomass and basal respiration in the upper-layer inter-shrub locations. The calculated metabolic coefficient （qCO2） revealed sig.i.icant differences between the two sampling sites as well as between the two soil layers, elucidating the abiotic effect between the sites throughout the study period. The substrate availability index was found to sig.i.icantly demonstrate the differences between the two sites, elucidating the sig.i.icant contribution of Z. duraosura in food source availability and in moderating harsh abiotic components. The importance of basal microbial parameters and the derived indices as tools demonstrated the importance and need for basic knowledge in understanding plant-soil interactions determined by an unpredictable and harsh desert environment.

关键词： basal respiration desert microbial biomass root zone soil

Social and ecological complexity is associated with gestural repertoire size of wild chimpanzees

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integrative Zoology 2020年第4期15卷 276-292页

作者： Sam g.B.ROBERTS Anna i.ROBERTS School of Psychology Faculty of HealthLiverpool John Moores UniversityLiverpoolUK institute of Human Biology and EvolutionAdam Mickiewicz University PoznanPoland Department of Psychology University of ChesterChesterUK

increasing our understanding of primate gestural communication can provide new insights into language evolution.A key question in primate communication is the association between the social relationships of primates and their repertoire of *** analyses can reveal how primates use their repertoire of gestural communication to maintain their networks of family and friends,much as humans use language to maintain their social *** this study we examined the association between the repertoire of gestures(overall,manual and bodily gestures,and gestures of different modalities)and social bonds(presence of reciprocated grooming),coordinated behaviors(travel,resting,co-feeding),and the complexity of ecology(***,illumination)and sociality(party size,audience),in wild East African chimpanzees(Pan troglodytes schweinfurthii).A larger repertoire size of manual,visual gestures was associated with the presence of a relationship based on reciprocated grooming and increases in social complexity.A smaller repertoire of manual tactile gestures occurred when the relationship was based on reciprocated grooming.A smaller repertoire of bodily gestures occurred between partners who jointly traveled for *** gesture repertoire size was associated with social complexity,complex ecology also influenced repertoire *** evolution of a large repertoire of manual,visual gestures may have been a key factor that enabled larger social groups to emerge during ***,the evolution of the larger brains in hominins may have co-occurred with an increase in the cog.i.ive complexity underpinning gestural communication and this,in turn,may have enabled hominins to live in more complex social groups.

关键词： chimpanzee ecology gesture repertoire size sociality social network analysis

Accretivity of the general Second Order Linear Differential Operator

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Acta Mathematica Sinica,Eng.i.h Series 2019年第6期35卷 832-852页

作者： V.g.MAZ'YA i.E.VERBiTSKY Department of Mathematics Linkoping University SE-581 83 Linkoping Sweden RUDN University 6 Miklukho-Maklay St. Moscow 117198 Russia Department of Mathematics University of Missouri Columbia Missouri 65211 USA

For the general second order linear differential operator ■ with complex-valued distributional coefficients a_(jk), b_j, and c in an open set Ω ? R^n(n ≥ 1), we present conditions which ensure that-L^0 is accretive... 详细信息

关键词： Accretive differential operators complex-valued coefficients Schr?dinger operator form boundedness

Fragmentation Cross Sections of 158 AgeV Pb Projectiles

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Chinese Physics Letters 2007年第10期24卷 2800-2803页

作者： g. Sher M.i. Shahzad M. Hussain Physics Division PINSTECH Islamabad Pakistan Department of Physics University of the Punjab Lahore Pakistan

We investigate the fragmentation cross sections of 158 AgeV ^207Pb projectile interacting with different targets using CR39 nuclear track detectors. The exposure is made at SPS beam facility of CERN. The detectors are chemically etched to obtain data in the form of etched cone length. The nuclear and electromagnetic contributions to the measured total charge-changing cross sections are investigated. The estimated results are compared with those found in the literature for similar research work.

关键词： coated conductor buffer layer self-epitaxy CeO2

Laminar Forced Convection in Curved Channel with Vortex Structures

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Journal of Thermal Science 2004年第2期13卷 143-149,162页

作者： A.A. AVRAMENKO S.g. KOBZAR i.V. SHEVCHUK A.V. KUZNETSOV B.i. BASOK institute of Engineering Thermophysics National Academy of SciencesKievUkraine Center for Energy Research National University of MexicoAp.P.3462580TemixcoMor.Mexico Dept.of Mechanical and Aerospace Engineering North Carolina State UniversityCampus Box 7910RaleighNC 27606-7910USA

Theoretical and experimental investigations of heat transfer in flat curvilinear channel have been carried out. Linear and non-linear effects of Dean vortexes on intensity of heat transfer were taken into account. The linear effect, which describe harmonic (sinuous) variation of the heat transfer coefficient near the concave surface of the channel and the non-linear effect causes the general increase of the heat transfer coefficient due to augmentation of heat transfer engendered by the Dean vortexes. For both effects, mathematical relations were obtained in the form of quadratures. These numerical results were modified to the form convenient in engineering calculations. The investigations have shown that both linear and nonlinear components grow up with the Dean number. Nonlinear component Q0T increases more abruptly, while the linear one Q1T is more conservative. This is a confirmation of stability of vortex structures.

关键词： heat transfer Dean vortexes curvilinear channel quadrature.

Thermogravimetric kinetic analysis of Nannochloropsis oculata combustion in air atmosphere

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Frontiers in Energy 2015年第2期9卷 125-133页

作者： SUKARNi SUDJiTO Nurkholis HAMiDi i.N.g. WARDANA Uun YANUHAR Department of Mechanical Engineering Faculty of Engineering StateUniversity of Malang J1. Semarang 5 Malang 65145 East-JavaIndonesia Department of Mechanical Engineering Faculty of EngineeringUniversity of Brawijaya J1. Mayjen Haryono 167 Malang 65145East-Java Indonesia Biotechnology Laboratory Department of Water Resources Manage-ment Faculty of Fisheries and Marine Sciences University ofBrawijaya J1. Veteran Malang 65145 East-Java Indonesia

The thermal behavior of Nannochloropsis oculata combustion in air atmosphere were investigated by performing experiments on STA PT1600 Thermal Analyzer at heating rates of 10℃/min, 40℃/min and 70℃/min and range of temperatures from room tempera- ture to 1200℃. The kinetic parameters were evaluated by using Kissinger and Ozawa methods. The result showed that Nannochloropsis oculata combustion occurred in five stages. Started with initial devolatilization, the main thermal decomposition and combustion process, transition stage, the combustion of char and the last stage was the slow burning reaction of residual char. in line with increasing heating rate, the mass loss rate increased as well, but it delayed the thermal decomposition processes toward higher temperatures. The average activation energy at the main thermal decomposition stage and the stage of char combustion were approximately 251 kJ/mol and 178 kJ/mol, respectively.

关键词： Nannochloropsis oculata combustion,kinetic parameters air atmosphere thermogravimetric

AN AUgMENTED BV SETTiNg FOR FEEDBACK SWiTCHiNg CONTROL

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Journal of Systems Science & Complexity 2010年第3期23卷 456-466页

作者： Falk M.HANTE günter LEUgERiNg Thomas i.SEiDMAN Department Mathematik Lehrstuhl für Angewandte Mathematik ⅡUniversitt Erlangen-Nürnberg Department of Mathematics and Statistics University of Maryland Baltimore County

This paper considers dynamical systems under feedback with control actions limited *** authors wish to understand the closed-loop systems as approximating multi-scale problemsin which the implementation of switching merely acts on a fast *** hybrid dynamicalsystems are extensively studied in the literature,but not much so far for feedback with partial *** becomes in particular relevant when the dynamical systems are governed by partialdifferential *** authors introduce an augmented BV setting which permits recog.i.ion ofcertain fast scale effects and give a corresponding well-posedness result for observations with such *** an application for this setting,the authors show existence of solutions for systemsof semilinear hyperbolic equations under such feedback with pointwise observations.

关键词： Feedback functions of bounded variation hybrid dynamical systems partial state observation switching control.

EPR and Magnetic Susceptibility investigation of Fe ions in B_2O_3-SrF_2 glass Matrix

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Journal of Materials Science & Technology 2002年第3期18卷 231-233页

作者： i.Ardelean g.Salvan 等 FacultyofPhysics Babes-BolyaiUniversity3400Cluj-NapocaRomania institutforPhysics TechnicalUniversityChemnitzGermany

The structural and magnetic properties of an oxide-fluoride mixed vitreous matrix 2B2O3-SrF2, were explored by using Fe impurities as probes. information about the structural units involving.i.on ions, their valence state, the strengths and type of interactions involving them was obtained using EPR spectroscopy and magnetic susceptibility measurements.

关键词： Boron oxide iron oxide Sr fluoride glass EPR Magnetic susceptibility

groundwater occurrence and flow patterns in the ishiagu mining area of southeastern Nigeria

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Frontiers of Earth Science 2012年第1期6卷 18-28页

作者： i.C.EZEKWE E.ODUBO g.N.CHiMA i.S.ONWUCHEKWA Department of geography and Environmental Management Niger Delta UniversityWilberforce IslandPMB 071YeneganaNigeria Department of geography and Planning Abia State UniversityPMB 2000UtumNigeria

The ishiagu area is a water scarce region and has played host to mining activities for more than four decades. Mining-related activities have become a threat to potable water supply in the area. This paper is an attempt to show the extent of this threat and in particular, investigate the regional groundwater occurrence and flow pattem based on gPS, water well and geological data. This basin- wide model can be used for further groundwater assess- ment, pollution control and contaminant management. groundwater occurs between 2.4 and 9 m in the Lekwesi- Lokpaukwu area; 1.5-3.7 m in the Ndi-Ugbugbor-Ayaragu axis and 1.2-4.6 m in the ishiagu area. Recharge areas include the Leru-Amaubiri-Lekwesi sandstone hills and the ihetutu-Ugwuajirija mine field. While the ultimate sink of contamiants is the ivo River system, other discharge axis is the ishiagu-Ayaragu axis and the Ogwor Ndi- Ugbugbor zone. An unconfined and a confined （〉 10） circulation groundwater system was inferred, and flow model reveals that a large part of ishiag-Ayaragu and Ndi- Ugbugbor part of the study area suffer polluted recharge from the Pb/Zn mining area. groundwater was also subjected to hierarchical cluster analysis and the existence of 3-4 hydrological regimes, which revealed： Unpolluted recharge areas, areas affected by polluted recharge, a deep water and shallow water circulation and mine effluents.

关键词： groundwater flow mining heavy metals,pollution cluster analysis ishiagu Nigeria