检索结果-南通市图书馆

Enriching plant diversity in grasslands by large-scale experimental sward disturbance and seed addition along gradients of land-use intensity

引用

Journal of Plant Ecology 2017年第4期10卷 581-591页

作者： valentin h.klaus Deborah Schäfer Till Kleinebecker Markus Fischer Daniel Prati Norbert hölzel Institute of Landscape Ecology Münster UniversityHeisenbergstr.248149 MünsterGermany Institute of Plant Sciences University of BernAltenbergrain 213013 BernSwitzerland

Aims The relationship between biodiversity and ecosystem functioning is among the most active areas of ecological ***,enhancing the diversity of degraded ecosystems is a major goal in applied restoration *** grasslands,many species may be locally absent due to dispersal or microsite limitation and may therefore profit from mechanical disturbance of the resident *** established a seed addition and disturbance experiment across several grassland sites of different land use to test whether plant diversity can be increased in these ***,the experiment will allow us testing the consequences of increased plant diversity for ecosystem processes and for the diversity of other taxa in real-world ***,we present details of the experimen-tal design and report results from the first vegetation survey 1 year after disturbance and seed ***,we tested whether the effects of seed addition and disturbance varied among grassland depending on their land use or pre-disturbance plant *** A full-factorial experiment was installed in 73 grasslands in three regions across *** were under regular agricul-tural use,but varied in the type and the intensity of management,thereby representing the range of management typical for large parts of Central *** disturbance treatment consisted of disturbing the top 10 cm of the sward using a rotavator or rotary *** addition consisted of sowing a high-diversity seed mixture of regional plant *** species were all regionally present,but often locally absent,depending on the resident vegetation composi-tion and richness of each *** Findings Seven months after sward disturbance,respective plots had significantly increased in bare soil,seedling species richness and number of *** addition had increased plant species richness,but only in combination with sward *** increase in species richness

关键词： grassland restoration germination microsite limitation seed limitation fertilization

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Influence of experimental soil disturbances on the diversity of plants in agricultural grasslands

引用

Journal of Plant Ecology 2014年第6期7卷 509-517页

作者： Jörg Müller Johannes heinze Jasmin Joshi Steffen Boch valentin h.klaus Markus Fischer Daniel Prati Institute of Biochemistry and BiologyUniversity of PotsdamMaulbeerallee 114469 PotsdamGermany Freie Universität Berlin Institut für BiologieBerlin-Brandenburg Institute of Advanced Biodiversity ResearchAltensteinstrasse 614195 BerlinGermany Institute of Plant Sciences University of BernAltenbergrain 213013 BernSwitzerland Institute of Landscape Ecology University of MünsterHeisenbergstr.248149 MünsterGermany Biodiversity and Climate Research Centre BIK-F Senckenberg Gesellschaft für Naturforschung603257 FrankfurtGermany

Aims and Methods Disturbance is supposed to play an important role for biodiversity and ecosystem stability as described by the intermediate disturbance hypoth-esis(IDh),which predicts highest species richness at intermediate levels of *** this study,we tested the effects of artificial soil distur-bances on diversity of annual and perennial vascular plants and bryo-phytes in a field experiment in 86 agricultural grasslands differing in land use in two regions of *** each grassland,we implemented four treatments:three treatments differing in application time of soil dis-turbances and one *** year after experimental disturbance,we recorded vegetation and measured biomass productivity and bare *** analysed the disturbance response taking effects of region and land-use-accompanied disturbance regimes into *** Findings Region and land-use type strongly determined plant species *** disturbances had small positive effects on the species richness of annuals,but none on perennials or *** ground was positively related to species richness of ***,exceeding the creation of 12%bare ground further distur-bance had a detrimental effect on bryophyte species richness,which corresponds to the *** biomass productivity was unaffected by disturbance our results indicate that the disturbance effect on spe-cies richness of annuals was not due to decreased overall produc-tivity,but rather due to short-term lowered inter-and intraspecific competition at the newly created ***,our results highlight the importance of soil disturbances for species richness of annual plants and bryophytes in agricultural ***,most grasslands were disturbed naturally or by land-use practices and our additional experimental soil dis-turbances only had a small short-term ***,total plant diversity in grasslands seemed to be more limited by the availabil-ity of propagules rather tha

关键词： annuals bryophytes colonization intermediate disturbance hypothesis microsites

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Green synthesis of luminescent La-MOF nanoparticle from waste poly(ethylene terephthalate) for high-performance in Fe(Ⅲ) detection

引用

Rare Metals 2024年第8期43卷 3833-3843页

作者： Zhi Gong Zhi-Kui Dai Zhi-Yue Dong Qiu-Xuan Liu valentin A.Milichko hua-Jian Liu Jie Liu Ran Niu Jiang Gong Key Laboratory of Material Chemistry for Energy Conversion and Storage Hubei Key Laboratory of Material Chemistry and Service FailureHubei Engineering Research Center for Biomaterials and Medical Protective MaterialsSemiconductor Chemistry CenterSchool of Chemistry and Chemical EngineeringMinistry of EducationHuazhong University of Science and TechnologyWuhan 430074China School of Chemical Engineering and Pharmacy Wuhan Institute of TechnologyWuhan 430073China Collaborative Innovation Center for Advanced Organic Chemical Materials Co-constructed by the Province and Ministry Ministry of Education Key Laboratory for the Synthesis and Application of Organic Functional Molecules and College of Chemistry and Chemical EngineeringHubei UniversityWuhan 430062China School of Physics and Engineering ITMO UniversitySt.Petersburg197101Russia School of Materials Science and Engineering Hubei UniversityWuhan430062China Guangdong Provincial Key Laboratory of Technique and Equipment for Macromolecular Advanced Manufacturing School of Mechanical and Automotive EngineeringKey Laboratory of Polymer Processing EngineeringMinistry of EducationSouth China University of TechnologyGuangzhou 510641China

Developing luminescent metal-organic frameworks(MOFs) capable of high-efficiency Fe^(3+)sensing has aroused great attraction in the fields of biology,chemistry,***,previous solvothermal methods are limited by organic solvent usage,time consuming,high pressure,and high-energy ***,we propose the waste-toMOF strategy towards the scale-up production of La-MOF nanoparticles through the ball milling of recycled poly(-ethylene terephthalate)(PET) bottles and La(NO_(3))_(3)·_(6)h_(2)*** goes on alkaline hydrolysis to form 1,4-benzenedicarboxylic acid sodium salt(Na_(2)BDC) and ethylene glycol by ball ***,BDC reacts with La^(3+)to form *** as-prepared La-MOF crystal nanoparticles possess a rod-like morphology with the size of few hundred ***,La-MOF nanoparticles display high selectivity and sensitivity for Fe^(3+)*** quenching constant and limit of detection are 5.29×10^(3)(mol·L^(-1))^(-1) and 0.147 μmol·L^(-1),respectively,thus surpassing many advanced Fe^(3+) *** to the result of density functional theory,the high Fe^(3+) detection performance of La-MOF is related to the complexing of Fe^(3+)with La-MOF,which leads to the gradual dissociation of the coordination bond between terephthalic acid and La^(3+).It is anticipated that the mechanochemistry milling-based wasteto-MOF strategy provides a new platform for the massive production of functional MOFs in a green manner.

关键词： Metal-organic framework Waste polyester Mechanochemistry milling Fluorescence sensor

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Inbreeding and genetic load in a pair of sibling grouse species:Tetrastes sewersowi and ***

引用

Avian Research 2024年第2期15卷 265-270页

作者： Kai Song Tom van der Valk Bin Gao Peter halvarsson Yun Fang Wendong Xie Siegfried klaus Zhiming han Yue-hua Sun Jacob hoglund Key Laboratory of Animal Ecology and Conservation Biology Institute of ZoologyChinese Academy of SciencesBeijing100101China Animal Ecology Department of Ecology and GeneticsUppsala UniversityNorbyvagen 18DUppsala75236Sweden Department of Cell and Molecular Biology Uppsala75273Sweden Unit of Parasitology Department of Biomedicine and Veterinary Public HealthSwedish University of Agricultural SciencesPO Box 7036Uppsala75007Sweden Lindenhohe 5 JenaD-07749Germany The State Key Laboratory of Reproductive Biology Institute of ZoologyChinese Academy of SciencesBeijing100101China

Genetic load and inbreeding are recognized as important factors to be considered in conservation *** levels of both can increase the risk of population extinction by negatively impacting fitness-related characters in many species of plants and animals,including humans(inbreeding depression).Genomic tech-niques are increasingly used in measuring and understanding genetic load and inbreeding and their importance in evolution and *** used whole genome resequencing data from two sibling grouse species in subarctic Eurasia to quantify *** found a large range of inbreeding measured as FROh(fraction of runs of homozygosity)in individuals from different populations of Chinese Grouse(Tetrastes sewerzowi)and hazel Grouse(***).FROh estimated from genome-wide runs of homozygosity(ROh)ranged from 0.02 to 0.24 among Chinese Grouse populations and from 0.01 to 0.44 in hazel *** from a population of Chinese Grouse residing in the Qilian mountains and from the European populations of hazel Grouse(including samples from Sweden,Germany and Northeast Poland)were the most inbred(FROh ranged from 0.10 to 0.23 and 0.11 to 0.44,respectively).These levels are comparable to other highly inbred populations of *** Grouse from northern China and Chinese Grouse residing in the Qinghai-Tibetan Plateau showed relatively lower inbreeding *** of the ratio between deleterious missense mutations and synonymous mutations revealed higher levels in Chinese Grouse as compared to hazel *** results are possibly explained by higher fixation rates,mutational melt down,in the range-restricted Chinese Grouse compared to the wide-ranging hazel ***,when we compared the relatively more severe class of loss-of-function muta-tions,hazel Grouse had slightly higher levels than Chinese Grouse,a result which may indicate that purifying selection(purging)has been more efficient in Chinese Grouse on this class of mutations.

关键词： Genetic load Inbreeding Purifying selection Qinghai-Tibetan Plateau ROh Tetrastes

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Free vibration and buckling analysis of polymeric composite beams reinforced by functionally graded bamboo fbers

引用

Applied Mathematics and Mechanics(English Edition) 2024年第3期45卷 543-562页

作者： h.M.FEIZABAD M.h.YAS Department of Mechanical Engineering Razi UniversityKermanshah ***Iran

Natural fibers have been extensively researched as reinforcement materials in polymers on account of their environmental and economic advantages in comparison with synthetic fibers in the recent *** fibers are renowned for their good mechanical properties,abundance,and short cycle *** beams are one of the fundamental structural components and are susceptible to mechanical loads in engineering applications,this paper performs a study on the free vibration and buckling responses of bamboo fiber reinforced composite(BFRC)beams on the elastic *** different functionally graded(FG)layouts and a uniform one are the considered distributions for unidirectional long bamboo fibers across the *** elastic properties of the composite are determined with the law of *** hamilton’s principle,the governing equations of motion are *** generalized differential quadrature method(GDQM)is then applied to the equations to obtain the *** achieved outcomes exhibit that the natural frequency and buckling load values vary as the fiber volume fractions and distributions,elastic foundation stiffness values,and boundary conditions(BCs)and slenderness ratio of the beam ***,a comparative study is conducted between the derived analysis outcomes for BFRC and homogenous polymer beams to examine the effectiveness of bamboo fibers as reinforcement materials,demonstrating the significant enhancements in both vibration and buckling responses,with the exception of natural frequencies for cantilever beams on the Pasternak foundation with the FG-◇fiber ***,the obtained analysis results of BFRC beams are also compared with those for carbon nanotube reinforced composite(CNTRC)beams found in the literature,indicating that the buckling loads and natural frequencies of BFRC beams are lower than those of CNTRC beams.

关键词： bamboo fiber free vibration buckling analysis functionally graded(FG)beam elastic foundation generalized differential quadrature method(GDQM)

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

holographic dark energy in non-conserved gravity theory

引用

Communications in Theoretical Physics 2024年第4期76卷 126-133页

作者： h R Fazlollahi Institute of Gravitation and Cosmology Peoples Friendship University of Russia(RUDN University)6 Miklukho-Maklaya StMoscow117198Russia

Recently, reconsidering the Rastall idea T_(μ;νν)^(v)=α_(,μ) through relativistic thermodynamics gives a new form for the scalar field α which led us to construct modern modified theory of gravity debugged ‘non-conserved gravity theory’ Fazlollahi 2023 Euro. Phys. J. C 83 923. This theory unlike other modified theories of gravity cannot directly explain the current acceleration expansion in the absence of the cosmological constant and or existence of other forms of dark energy. hence, in this study we have reinvestigated holographic dark energy Ρ_(X)~h^(2) in the non-conserved theory of gravity. In this context, the density and pressure of dark energy depend on the non-conserved term and density of the dust matter field. As shown, due to non-conservation effects on large-scale structures, unlike the original holographic model, our model onsets an acceleration epoch for the current Universe satisfies observations. Moreover, the interaction and viscous scenarios are studied for this model.

关键词： non-conserved gravity covariant form of thermodynamics holographic dark energy

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Novel synthesis of stabilized Bi1-x-yGdxDyyO1.5 solid electrolytes with enhanced conductivity for intermediate temperature solid oxide fuel cells（SOFCs）

引用

Journal of Rare Earths 2024年第10期42卷 1903-1911页

作者： Ahmed h.Ibrahim Yehia M.Abbas h.A.Ayoub Marwa h.Ali Mustafa Aldoori Materials Science Laboratory Physics DepartmentFaculty of ScienceSuez Canal University Ministry of higher Education and Scientific Research Aliraqia University

herein,we report the synthesis of a Dy-Gd co-doped cubic phase-stabilized Bi2O3solid electrolyte system via solid-state processing under atmospheric *** with Dy3+and Gd3+has been observed to significantly enhance the densification process during sintering for stabilization purposes,thereby improving the electrical properties of δ-Bi2O3-type *** synthesized ceramics were characterized using X-ray diffraction（XRD）,field emission scanning electron microscopy-energy dispersive X-ray spectroscopy（FESEM-EDX）,thermal gravimetry/differential thermal analysis（TG/DTA）,and the four-point probe technique（4PPT）.XRD analysis reveals that the samples Bi1-x-yGdxDyyO1.5（y=0.05/x=0.05,0.10,0,15,and 0.20,and x=0.05/y=0.10,0.15,and 0.20） exhibit a stable face-centered cubic δ-phase and a mixed-phase crystallographic *** XRD analysis of the stabilized δ-phase suggests that the prepared oxides show a face-centered cubic（FCC） structure with a space group of *** micrographs reveal that the composition Bi0.90Gd0.05Dy0.05O1.5has no significant ***,an evident increase in the pore formation is observed as the amount of Gd2O3increases until it reaches 20%.This finding suggests that dense pellets are formed during the sintering process at 900-1000℃.The DTA analyses were performed to verify the phase stability,which agrees with the XRD *** electrochemical performance of the synthesized Dy-Gd co-doped Bi2O3solid electrolyte system was evaluated and analyzed in detail by using the electrochemical impedance spectroscopy（EIS） technique,Based on EIS and conductivity measurements,Bi0.75Gd0.20Dy0.05O1.5exhibits the lowest activation energy of 0.519 eV and the highest conductivity value of 0.398 S/cm at 627℃compared to the other samples;this composition can be used as a solid electrolyte for intermediatetemperature solid oxide fuel cells（SOFCs）.

关键词： Electrochemical impedance spectroscopy (EIS) Fast Fourier transform (FFT) Rare earths Rietveld Solid oxide fuel cells (SOFCs) Solid-state processing

来源：

同方期刊数据库评论

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Convexification of hybrid AC-DC Optimal Power Flow with Line-Commutated Converters

引用

CSEE Journal of Power and Energy Systems 2024年第2期10卷 617-628页

作者： hongyuan Liang Zhigang Li J.h.Zheng Q.h.Wu School of Electric Power Engineering South China University of TechnologyGuangzhou 510641China

Line-commutated converter (LCC)-based high-voltage DC (hVDC) systems have been integrated with bulk AC power grids for interregional transmission of renewable power. The nonlinear LCC model brings additional nonconvexity to optimal power flow (OPF) of hybrid AC-DC power grids. A convexification method for the LCC station model could address such nonconvexity but has rarely been discussed. We devise an equivalent reformulation for classical LCC station models that facilitates second-order cone convex relaxation for the OPF of LCC-based AC-DC power grids. We also propose sufficient conditions for exactness of convex relaxation with its proof. Equivalence of the proposed LCC station models and properties, exactness, and effectiveness of convex relaxation are verified using four numerical simulations. Simulation results demonstrate a globally optimal solution of the original OPF can be efficiently obtained from relaxed model.

关键词： AC-DC power system convex relaxation linecommutated converter optimal power flow second-order cone programming

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Shell-model representations of the microscopic version of the Bohr-Mottelson collective model

引用

Communications in Theoretical Physics 2024年第8期76卷 79-90页

作者： h G Ganev Joint Institute for Nuclear Research DubnaRussia Institute of Mechanics Bulgarian Academy of SciencesSofiaBulgaria

The structure of the irreducible collective spaces of the group Sp(12,R),which many-particle nuclear states are classified according to the chain Sp(12,R)⊃U(6)⊃SO(6)⊃SU_(pn)(3)⊗SO(2)⊃SO(3)of the proton-neutron symplectic model(PNSM),is considered in *** chain of the PNSM was recently shown to correspond to a microscopic shell-model version of the Bohr-Mottelson collective *** construction of the relevant shell-model representations of the Sp(12,R)group along this chain is considered for three nuclei with varying collective properties and from different mass *** is shown that the SU_(pn)(3)basis states of the Sp(12,R)representations belonging to the SO(6)irreps with seniorityυ≥υ0,withυ0 denoting the maximal seniority SO(6)irrep contained in the Sp(12,R)bandhead,are always Pauli allowed,but organized in a different way into different SO(6)*** is in contrast to the case of filling the levels of the standard three-dimensional harmonic oscillator and using the plethysm *** the SU_(pn)(3)multiplets withinυhe present work are important for the practical application of the microscopic version of the Bohr-Mottelson collective model.

关键词： microscopic shell-model version of the Bohr-Mottelson model proton-neutron symplectic model Sp(12,R)dynamical algebra shell-model representations

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Marinoan glaciation in the Indian subcontinent——Anatomy and global implications

引用

Journal of Palaeogeography 2024年第2期13卷 293-308页

作者： h.N.Bhattacharya Department of Earth Sciences Techno India UniversityWest BengalSector VSalt LakeKolkata700091India

Detailed sedimentological analysis of the Pokaran Boulder Bed,representing the most basal unit of the Neoproterozoic-Lower Cambrian Marwar Supergroup,clearly indicates its glacial *** glacial sediments are interpreted as an ice-contact submarine fan *** on the detrital and inherited zircon population of the Marwar Supergroup sediments and interlayered pyroclastic deposits,a Marinoan cryochron of the Cryogenian Period is envisaged for the Pokaran Boulder *** well-preserved Ediacaran elements in the post-glacial sedimentary succession also support a Cryogenian to Early Cambrian age of the Marwar *** glacial deposition at the base of the Marwar Supergroup strengthens the regional correlation between the studied sediments with the Lesser himalayan Blaini-Krol-Tal sediments and the haqf Supergroup of *** available zircon ages and paleomagnetic data of the Malani Igneous suite,along with the Marinoan glacial deposits,detrital zircon ages,and Ediacaran fossil elements of the Marwar Supergroup add significant information to the Neoproterozoic Earth history.

关键词： Neoproterozoic Marinoan glaciation Diamictites Pokaran Boulder Bed Marwar Supergroup

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

欢迎您,

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案：

请选择收藏分类：

通借通还

欢迎您,

建议与咨询 留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案： 新增检索档案 确定 取消

请选择收藏分类： 新增自定义分类 确定 取消

通借通还

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

请选择保存的检索档案：

请选择收藏分类：