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Rehabilitation of degraded areas in northeastern Patagonia, Argentina: Effects of environmental conditions and plant functional traits on performance of native woody species

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Journal of Arid Land 2020年第4期12卷 653-665页

作者： Juan m ZEBERiO Carolina A PÉREZ National University of Río Negro Atlantic HeadquartersCenter for Environmental Studies from Norpatagonia(CEANPa)Viedma 8500Argentina National Council of Scientific and Technical Research(CONiCET) Viedma 8500Argentina Ecological and Environmental Systems Research Laboratory(LiSEA) National University of La PlataLa Plata 1900Argentina

Degradation processes affect a vast area of arid and semi-arid lands around the world and damage the environment and people′s health. Degradation processes are driven by human productive activities that cause direct and indirect effects on natural resources, such as species extinction at regional scale, reduction and elimination of vegetation cover, soil erosion, etc. in this context, ecological rehabilitation is an important tool to recover key aspects of the degraded ecosystem. Rehabilitation trials rely on the use of native plant species with characteristics that allow them to obtain high survival and growth rates. The aim of this work was to assess the survival and growth of native woody species in degraded areas of northeastern Patagonia and relate them to plant functional traits and environmental variables. We observed high early and late survival rates, and growth rates in Prosopis flexuosa DC. var. depressa F.A. Roig and Schinus johnstonii F.A. Barkley, and low values in Condalia microphylla Cav. and Geoffroea decorticans(Gillies ex Hook. & Arn.) Burkart. Early survival rates were positively associated with specific leaf area(SLA) and precipitation, but negatively associated with wood density, the maximum mean temperature of the warmest month and the minimum mean temperature of the coldest month. Late survival rates were positively associated with SLA and soil organic matter, but negatively associated with plant height and precipitation. The temperature had a positive effect on late survival rates once the plants overcame the critical period of the first summer after they were transplanted to the field. Prosopis flexuosa and S. johnstonii were the most successful species in our study. This could be due to their functional traits that allow these species to acclimatize to the local environment. Further research should focus on C. microphylla and G. decorticans to determine how they relate to productive conditions, acclimation to environmental stress, auto-eco

关键词： arid lands Condalia microphylla Geoffroea decorticans Prosopis flexuosa Schinus johnstonii survival rates height growth basal diameter growth

Three-body Faddeev calculations for _(ΛΛ)^(6)He and _(ΩΩ)^(6)He hypernuclei

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Chinese Physics C 2022年第10期46卷 147-155页

作者： Faisal Etminan m.R.Hadizadeh Department of Physics Faculty of SciencesUniversity of BirjandBirjand 97175-615Iran College of Engineering ScienceTechnology and AgricultureCentral State UniversityWilberforceOH45384USA Department of Physics and Astronomy Ohio UniversityAthensOH45701USA

We study the ground-state properties of the _(YY)^(6)He double hyperon for _(ΛΛ)^(6)He and _(ΩΩ)^(6)He nuclei in a threebody model(Y+Y+α).We solve two coupled Faddeev equations corresponding to the three-body configurations(αY,Y)and(YY,α)in configuration space with the hyperspherical harmonics expansion method by employing the most recent hyperon-hyperon interactions obtained from lattice QCD *** numerical analysis for _(ΛΛ)^(6)He,using threeΛΛlattice interaction models,leads to a ground state binding energy in the(-7.468,-7.804)meV domain and the separations and in the domains of(3.555,3.629)fm and(2.867,2.902)fm,*** binding energy of the double-Ω hypenucleus _(ΩΩ)^(6)He leads to -67.21 meV and consequently to smaller separations =1.521 fm and =1.293 *** addition to geometrical properties,we study the structure of ground-state wave functions and show that the main contributions are from the s-wave *** results are consistent with the existing theoretical and experimental data.

关键词： ΩΩ(^(1)S_(0))potential multi-strangeness nucleus cluster model hyperspherical harmonics

高海拔下锌的高浸出率——谢里特为中国西部矿业公司进行的锌氧压浸出研究

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中国有色冶金 2009年第3期38卷 16-21页

作者： m.J.Collins R.J.Kalanchey i.m.masters N.E.Tuffrey 杨征谢里特国际公司西部矿业股份有限公司青海西宁811600

西部矿业(WmC)甘河精炼厂海拔高,WmC矿山生产的精矿含铁高,这两点是WmC为其新的锌精炼厂选择氧压浸出工艺的关键因素。谢里特公司在萨斯喀彻温堡用WmC从中国青海省提供的精矿样品进行了氧压浸出试验,本论文描述了该试验的结果。小型间... 详细信息

西部矿业(WmC)甘河精炼厂海拔高,WmC矿山生产的精矿含铁高,这两点是WmC为其新的锌精炼厂选择氧压浸出工艺的关键因素。谢里特公司在萨斯喀彻温堡用WmC从中国青海省提供的精矿样品进行了氧压浸出试验,本论文描述了该试验的结果。小型间断氧压浸出试验和四天连续扩大试验的结果都进行了报告。连续扩大试验包括两段氧压浸出、中和及除铁的连续操作,产出无铁硫酸锌溶液。氧压浸出取得了大于98%的锌浸出率,同时产出含有约9 g/L硫酸和2 g/L铁的溶液。中和及除铁后,溶液约含170g/L锌和mg/L的铁。从锌精矿原料到元素硫副产品的总硫回收率约为85%,从中和渣中可回收原料中75～80%的铟。试验结果显示了谢里特锌氧压浸出工艺的技术和经济优势,并且为工程设计提供了所需数据。

关键词：氧压浸出高海拔高铁锌精矿高浸出率

Ancient deep roots for mesozoic world-class gold deposits in the north China craton:An integrated genetic perspective

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Geoscience Frontiers 2020年第1期11卷 203-214页

作者： Cheng-Xue Yang m.Santosh School of Earth Sciences and Resources China University of Geosciences(Beijing)Beijing 100083China Department of Earth Sciences University of AdelaideAdelaideSA 5005Australia Key Lab of Submarine Geosciences and Prospecting Techniques Ministry of EducationCollege of Marine GeosciencesOcean University of ChinaQingdao 266100China Yonsei Frontier Lab Yonsei UniversitySeoul 03722Republic of Korea

The North China Craton(NCC)hosts some of the world-class gold deposits that formed more than 2 billion years after the major orogenic cycles and *** diverse models for the genesis of these deposits remain equivocal,and mostly focused on the craton margin examples,although synchronous deposits formed in the interior *** we adopt an integrated geological and geophysical perspective to evaluate the possible factors that contributed to the formation of the major gold deposits in the *** the Archean tectonic framework of the NCC,the locations of the major gold deposits fall within or adjacent to greenstone belts or the margins of *** the Paleoproterozoic framework,they are markedly aligned along two major collisional sutures-the Trans North China Orogen and the Jiao-Liao-Ji *** the mesozoic intrusions hosting these deposits do not carry adequate signals for the source of gold,we explore the deep roots based on available geophysical *** show that the gold deposits are preferentially distributed above zones of uplifted mOHO and shallow LAB corresponding to thinned crust and eroded sub-lithospheric mantle,and that the mineralization is located above regions of high heat flow representing mantle *** NCC was at the center of a multi-convergent regime during the mesozoic which intensely churned the mantle and significantly en riched *** geophysical data on moho and LAB upwarp from the centre towards east of the craton is more consistent with paleo-Pacific slab subduction from the east exerting the dominant control on lithospheric *** on these results,and together with an evaluation of the geochemical and isotopic features of the mesozoic magmatic intrusions hosting the gold mineralization,we propose a genetic model that invokes reworking of ancient Au archives preserved in the lower crust and metasomatised upper mantle and which were generated through multiple subduction,underplating and cumulation ev

关键词： Gold metallogeny Subduction tectonics Lithospheric thinning mantle metasomatism North China craton

Synthesis of Nanocrystalline Barium Ferrite in Ethanol/Water media

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Journal of materials Science & Technology 2009年第4期25卷 465-469页

作者： m. montazeri-Pour A. Ataie School of metallurgy and materials Engineering University of Tehran

Nanocrystalline particles of barium ferrite magnetic material have been prepared by co-precipitation route using aqueous and non-aqueous solutions of iron and barium chlorides with a Fe/Ba molar ratio of 11 and subsequent drying-annealing treatment. Water and ethanol/water mixture with volume ratio of 3：1 were used as solvents in the process. Coprecipitated powders were annealed at various temperatures for 1 h. FTiR （Fourier transform infrared spectroscopy）, XRD （X-ray diffraction）, DTA/TGA （differential thermal analy- sis/thermogravimetric analysis） and SEm （scanning electron microscopy） techniques were used to evaluate powder particle characteristics. DTA/TGA results confirmed by those obtained from XRD indicated that the formation of barium ferrite occurs in sample synthesized in ethanol/water solution at a relatively low temper- ature of 631℃. Nano-size particles of barium ferrite with mean particle size of almost 75 and 100 nm were observed in the SEm micrographs of the samples synthesized in ethanol/water solution after annealing at 700 and 800℃ for 1 h, respectively.

关键词： magnetic materials Hard ferrites Coprecipitation

Faddeev calculations on lambda hypertriton with potentials from Gel'fand–Levitan–marchenko theory

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Communications in Theoretical Physics 2020年第10期72卷 119-124页

作者： E F meoto m L Lekala Department of Physics University of South AfricaPrivate Bag X61710 JohannesburgSouth Africa

Effective lambda-proton and lambda-neutron potentials,restored from theoretical scattering phases through Gel'fand–Levitan–marchenko theory,are tested on a lambda hypertriton through three-body *** lambda hypertriton is treated as a three-body system consisting of lambda-proton,lambda-neutron and proton–neutron *** energy and root mean square radius are computed for the ground state of lambda hypertriton(Jp=12+).in coordinate space,the dynamics of the system is described using a set of coupled hyperradial equations obtained from the differential Faddeev *** solving the eigenvalue problem derived from this set of coupled hyperradial equations,the binding energy and root mean square matter radius computed are found to be-2.462 meV and 7.00 fm,*** potentials are also shown to display a satisfactory convergence behaviour.

关键词： lambda-nucleon potential lambda-proton potential lambda-neutron potential lambda hypertriton Faddeev equations hyperspherical method

The ionosphere under extremely prolonged low solar activity

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The ionosphere under extremely prolonged low solar activity

microhabitat characteristics related to seasonal roost switching:implications from a threatened and introduced cockatoo species in an urban landscape

中国科学院地质与地球物理研究所第11届（2011年度）学术年会

作者： Vladimir i.Kurkin Nelya m.Polekh Chien-Chih Lee institute of Solar-Terrestrial Physics Russian Academy of Sciences IrkutskRussia General Education Center Ching-Yun University JhungliTaiwan

[1]A critical question in ionospheric physics is the state of the ionosphere and relevant processes under extreme solar *** solar activity during 2007-2009 is extremely prolonged low,which offers us a unique opportunity to explore this issue. in this study,we collected the global ionosonde measurements of the F layer critical frequency(fF),E layer critical frequency(fE),and F layer virtual height(h’F) and the total electron content(TEC) maps produced by the Jet Propulsion Laboratory,which were retrieved from dual-frequency GPS receivers distributed worldwide,to investigate the ionospheric phenomena during solar minimum of cycle 23/24,particularly the difference in the ionosphere between solar minima of cycle 23/24 and the preceding *** analysis indicates that the moving 1 year mean fF at most ionosonde stations and the global average TEC went to the lowest during cycle 23/24 *** solar cycle differences in fF minima display local time dependence,being more negative during the daytime than at ***,the cycle difference in daytime fF minima is about -0.5 mHz and even reaches to around -1.2 *** contrast,a complex picture presents in global h’F and fE,Evident reduction exists prevailingly in the moving 1 year mean hF at most stations,while no huge differences are detected at several stations.A compelling feature is the increase in fJE at some stations,which requires independent data for further *** analysis indicates that record low fF and low TEC can be explained principally in terms of the decline in solar extreme ultraviolet irradiance recorded by SOHO/SEm,which suggests low solar EUV being the prevailing contributor to the unusual low electron density in the ionosphere during cycle 23/24 *** also verifies that a quadratic fitting still reasonably captures the solar variability of fF and global average TEC at such low solar activity levels.

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Avian Research 2021年第3期12卷 317-326页

作者： Sifeng Wang L.m.Chu School of Life Sciences The Chinese University of Hong KongShatinNTHong Kong SARChina

Background:Communal roosting is a common avian social behaviour,which potentially provides foraging benefits,predation avoidance or thermoregulation in *** identify the crucial environmental factors associated with roost site selection,most studies have focused on the comparison of physical characteristics between roosts and ***,the differences among roosts have usually been neglected and the causes of roost switching have seldom been ***:To explore the variations among roost sites and assess the most influential environmental factors related to seasonal roost switching,we conducted a 105-day observation on an introduced population of critically endan-gered Yellow-crested Cockatoo(Cacatua sulphurea)in an urban environment in Hong Kong from 2014 to *** identified seven roost sites that were occupied in different seasons and then measured their microhabitat character-istics in terms of land use types,human disturbance and microclimate *** quantify these differences,we used Pearson’s chi-squared test,partial least squares determinant analysis(PLS-DA)and one-way repeated measures ANOVA,***:Our results distinguished roost sites occupied in three seasons,***,summer and winter roosts,using several microhabitat *** land use types were significantly associated with roosts,where spring roosts were usually located in tree-dominated areas,which are the major feeding *** discriminant analysis on human disturbance variables indicated that summer roosts were positively associated with night *** microhabitat temperatures of winter roosts were significantly higher than those of most other roosts on cold ***:The results highlighted significant variations among roosts,and seasonal roost switching was likely driven by specific microhabitat characteristics of each roost site,such as *** also helps us understand the behavioural adaptation of birds to

关键词： Communal roosting Human disturbance Land use microclimate Seasonal variation

Combustion characteristics of low-quality lignite for different bed material sphericities in a circulating fluidized bed boiler:A numerical study

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Particuology 2024年第7期90卷 364-382页

作者： Barış Gürel Gülşah Karaca Dolgun Osman ipek Ali Keçebaş Department of mechanical Engineering Engineering FacultySüleyman Demirel UniversityÇünürIspartaTurkey Department of Energy Systems Engineering Technology FacultyMuğla SıtkıKoçman UniversityKötekliMenteşeMuğlaTurkey

This study delves into the combustion behavior of various lignite types within a circulating fluidized bed boiler(CFBB),with a primary focus on the impact of different bed material sphericity ratios(0.5,0.7,and 0.9).Utilizing bed material with a sphericity ratio of 0.9 sourced from theÇan power plant and verified through experimentation,the research reveals several key ***,furnace temperatures tended to rise with higher sphericity ratios,albeit with variations between lignite types,particularly highlighting the complexity of this relationship in the case of GLi-Tunçbilek *** levels in the combustion chamber remained consistent across different sphericity ratios,indicating minimal influence on pressure *** combustion efficiency,especially at the bottom of the boiler,was observed at lower sphericity levels(0.5 and 0.7)forÇan lignite,as reflected in CO_(2) mole *** NO_(x) emissions generally decreased with lower sphericity,the sensitivity to sphericity varied by lignite type,with ilgın lignite showcasing low NO_(x) but high SO_(2) emissions,underscoring the intricate interplay between lignite properties,sphericity,and ***,this study advances our understanding of CFBB combustion dynamics,offering insights valuable for optimizing performance and emissions control,particularly in lignite-based power.

关键词： Circulating fluidized bed boiler Computational particle fluid dynamics method Particle sphericity ratios NO_(x)and SO_(2)emissions Energy production efficiency