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Patterns of grassland invasions by trees: insights from demographic and genetic spatial analyses

Journal of Plant Ecology 2015年第5期8卷 468-479页

作者： martin Dovčiak Richard Hrivnák karol Ujházy Dušan Gömöry State University of New York College of Environmental Science and Forestry(SUNY ESF)1 Forestry DriveSyracuseNY 13210USA Institute of Botany Slovak Academy of SciencesDúbravskácesta 9Bratislava 84523Slovakia Technical University in Zvolen Faculty of ForestryT.G.Masaryka 24Zvolen 96053Slovakia

Aims Woody invasions into grasslands have increased globally due to changing land use,climate and introduced woody species,but spatial processes generating and sustaining these invasions are not well *** gain insight into the patterns of spread of tree populations within grasslands,and to propose a full spatial analytical toolbox for studying native and non-native woody spe-cies spread when long-term data are not available,we tested if 50 years of grassland invasion in Western Carpathians by Norway spruce(Picea abies karst.)proceeded by one of the two tradi-tionally competing hypotheses of species spread:(i)by frontier expansion,or(ii)by advanced groups established ahead of the population *** also tested whether the pattern of invasion changed over *** We analyzed the spatial demographic and genetic patterns of a Norway spruce population invading a Western Carpathian grass-land using ripley’s L(t)and genetic kinship coefficients(Fij).We mapped and genotyped spruce trees across the invasion front(from the invasion leading edge to fully colonized grassland near the source population)using three demographic classes(adults,juve-niles and seedlings)to approximate the temporal aspects of the *** studied how the spatial patterns of invasion by indi-vidual demographic classes and their genetic kinship varied among adjacent plots established at different distances from the source population(ranging from 0 to 160 m,in 40-m distance increments).Important Findings Juveniles were positively genetically related to adults on fine scales(m),suggesting that adults within the grassland acted as a seed source and accelerated early ***,adults did not act as nucleation centers for the formation of advanced juvenile ***,geneti-cally unrelated juveniles formed groups independently of *** groups were small and separate at the leading edge but they increased in size and graded into a continuous zone near the source popul

关键词： genetic spatial structure mountain meadows point pattern analysis population structure secondary succession

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A Phenomenological Constitutive Law for the Description of Nonlinear Post-yield Behaviour of Glassy Polymers under Different Strain Rate

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宁波大学学报(理工版) 2003年第4期16卷 382-387页

作者： F.ZA■RI k.WOZNICA m.na■T ABDELAZIZ Universite des Sciences et Technologies de Lille Ecole Polytechnique Universitaire de Lille Laboratoire de Mecanique de Lille(UMR CNRS 8107)59655 Villeneuve d’Ascq cedex France

In this study, a modelization of the viscoplastic behaviour of amorphous polymers is proposed, from an approach originally developed for metals behaviour at high temperature, in which state variable constitutive equations have been modified. The model includes the effect of strain rate sensitivity, strain softening and strain hardening. A procedure for the identification of model parameters is developed through the use of experimental data from uniaxial tests extracted from the literature, across a variety of strain rates and below the glass transition temperature ( Tg). The numerical algorithm shows that the predictions of this model well describe the intrinsic softening upon yield threshold and the subsequent progressive orientational hardening typical for amorphous glassy polymers.

关键词： viscoplasticity parameters identification glassy polymers behaviour

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AnaLYSIS OF A FULLY DISCRETE FINITE ELEmENT mETHOD FOR PARABOLIC INTERFACE PROBLEmS WITH NONSmOOTH INITIAL DATA

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Journal of Computational mathematics 2022年第5期40卷 777-793页

作者： kai Wang na Wang Department of mathematics Southern University of Science and TechnologyShenzhen 518005China Applied and Computational mathematics Division Beijing Computational Science Research CenterBeijing 100193China

This article concerns numerical approximation of a parabolic interface problem with general L 2 initial *** problem is discretized by a finite element method with a quasi-uniform triangulation of the domain fitting the interface,with piecewise linear approximation to the *** semi-discrete finite element problem is furthermore discretized in time by the k-step backward difference formula with k=1,...,*** maintain high-order convergence in time for possibly nonsmooth L 2 initial value,we modify the standard backward difference formula at the first k−1 time levels by using a method recently developed for fractional evolution *** error bound of O(t−k nτk+t−1 n h 2|log h|)is established for the fully discrete finite element method for general L 2 initial data.

关键词： Parabolic interface problem Finite element method Backward difference formulae Error estimate Nonsmooth initial data.

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SYNTHESIS AND PROPERTIES OF BIFUNCTIOnaL mAGNETIC-OPTICAL naNOmATERIALS:Fe_2O_3@PDmAEmA-CAPPED Ⅱ－Ⅵ SEmICONDUCTOR QUANTUm DOTS naNOCOmPOSITES

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Chinese Journal of Polymer Science 2013年第9期31卷 1233-1241页

作者： na-na Zhao Wei Nie Jun mao Wei-cai Wang Xiang-ling Ji State key Laboratory of Polymer Physics and Chemistry Changchun Institute of Applied Chemistry Chinese Academy of Sciences

A facile route to synthesize a new type of multifunctional nanocomposites is reported. Here, PDmAEmA （poly[2- （dimethylamino）ethyl] methacrylate） is a key macromolecule serving as a bridge between magnetic FeaO3 nanoparticles and luminescent quantum dots. Both Fe203 nanoparticles and II-VI semiconductor quantum dots with a narrow size distribution are synthesized through a two-phase thermal approach. Subsequently, the atom transfer radical polymerization （ATRP） technique was applied to prepare magnetic Fe203@PDmAEmA core-shell nanoparticles. The thickness of PDmAEmA shell can be easily controlled by adjusting the reaction time. Finally, the ligand exchange method was exploited to modify II-VI quantum dot with amine-containing polymer of PDmAEmA, which led to quantum dot securely bound by Fe203@PDmAEmA core-shell nanoparticle to form a multifunctional nanocomposite. The resulting nanocomposite remains variable emission by tuning the II-VI semiconductor type and particle size and shows/arc at 49 kA/m and Tb at 16 k from Fe2O3 nanoparticles. The self-assembled behavior for the resulting samples is also discussed.

关键词： Bifunctional nanocomposite magnetic-optical PDmAEmA Semiconductor ATRP Two-phase method.

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Nonaqueous potassium-ion full-cells:mapping the progress and identifying missing puzzle pieces

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Journal of Energy Chemistry 2024年第6期93卷 384-399,I0010页

作者： Badre Larhrib Louiza Larbi Lénaïc madec Universite de Pau et des Pays de l’Adour E2S UPPACNRSIPREMPauFrance Universitéde Haute-Alsace Institut de Science des Matériaux de Mulhouse(IS2M)CNRS UMR 7361F-68100 MulhouseFrance Universitéde Strasbourg F-67081 StrasbourgFrance Réseau sur le Stockage Electrochimique de l’Energie CNRS FR3459AmiensFrance Institut des matériaux Jean Rouxel(ImN) CNRS UMR 6502Univ.Nantes44322 Cedex 3 NantesFrance

This review addresses the growing interest for potassium-ion full-cells(kIFCs)in view of the transition from potassium-ion half-cells(kIHCs)toward commercial k-ion batteries(kIBs).It focuses on the key parameters of kIFCs such as the electrode/electrolyte interfaces challenge,major barriers,and recent advancements in *** strategies for enhancing kIFC performance,including interfaces co ntrol,electrolyte optimization,electrodes capacity ratio,electrode material screening and electrode design,are *** review highlights the need to evaluate kIBs in full-cell configurations as half-cell results are strongly impacted by the k metal *** also emphasizes the importance of understanding solid electrolyte interphase(SEI)formation in kIFCs and explores promising nonaqueous as well as quasiand all-solid-state electrolytes *** review thus paves the way for practical,cost-effective,and scalable kIBs as energy storage systems by offering insights and guidance for future research.

关键词： k-ion full-cells Potassium-ion batteries Cross-talk Solid-state batteries Potassium reactivity Electrolyte design Electrode design

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Dna-assembled bimetallic plasmonic nanosensors

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Light(Science & Applications) 2014年第1期3卷 1-4页

作者： na Li Andreas Tittl Song Yue Harald Giessen Chen Song Baoquan Ding na Liu national Center for nanoscience and Technology Beijing 100190China th Physics Institute and Research Center Scope University of StuttgartD-70569 StuttgartGermany max Planck Institute for Intelligent Systems D-70569 StuttgartGermany

Plasmonic hybrid nanomaterials are highly desirable in advanced sensing *** components in these materials undertake distinct roles and work *** material component may act as an efficient light concentrator and optical probe,whereas another provides specific chemical or biological *** this work,we present Dna-assembled bimetallic plasmonic nanostructures and demonstrate their application for the all-optical detection of ***(Au)nanorods are functionalized with Dna strands,which serve both as linkers and seeding sites for the growth of palladium(Pd)nanocrystals and facilitate reliable positioning of Pd satellites around an Au nanorod at an ultrashort spacing in the nanometer ***-field scattering spectra of single Au–Dna–Pd nanorods were recorded during controlled cycles of hydrogen gas exposure,and an unambiguous concentration-dependent optical response was *** method enables,for the first time,the all-optical detection of hydrogen-induced phase-change processes in sub-5-nm Pd nanocrystals at the single-antenna *** substituting the Pd satellites with other functional materials,our sensor platform can be extended to plasmonic sensing of a multitude of chemical and biological reagents,both in liquid and gaseous phases.

关键词： Dna self-assembly hydrogen sensing palladium plasmonics

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Biosorption of copper ions from dilute aqueous solutions on base treated rubber (Hevea brasiliensis) leaves powder: kinetics, isotherm, and biosorption mechanisms

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Journal of Environmental Sciences 2008年第10期20卷 1168-1176页

作者： W.S.Wan Ngah m.A.k.m.Hanafiah School of Chemical Sciences Universiti Sains malaysia Penang 11800 malaysia.

The effciency of sodium hydroxide treated rubber (Hevea brasiliensis) leaves powder (NHBL) for removing copper ions from aqueous solutions has been investigated. The e?ects of physicochemical parameters on biosorption capacities such as stirring speed, pH, biosorbent dose, initial concentrations of copper, and ionic strength were studied. The biosorption capacities of NHBL increased with increase in pH, stirring speed and copper concentration but decreased with increase in biosorbent dose and ionic strength. The isotherm study indicated that NHBL fitted well with Langmuir model compared to Freundlich and Dubinin-Radushkevich models. The maximum biosorption capacity determined from Langmuir isotherm was 14.97 mg/g at 27°C. The kinetic study revealed that pseudo- second order model fitted well the kinetic data, while Boyd kinetic model indicated that film diffusion was the main rate determining step in biosorption process. Based on surface area analysis, NHBL has low surface area and categorized as macroporous. Fourier transform infrared (FT-IR) analyses revealed that hydroxyl, carboxyl, and amino are the main functional groups involved in the binding of copper ions. Complexation was one of the main mechanisms for the removal of copper ions as indicated by FT-IR spectra. Ion exchange was another possible mechanism since the ratio of adsorbed cations (Cu2+ and H+) to the released cations (na+, Ca2+, and mg2+) from NHBL was almost unity. Copper ions bound on NHBL were able to be desorbed at > 99% using 0.05 mol/L HCl, 0.01 mol/L HNO3, and 0.01 mol/L EDTA solutions.

关键词： copper treated rubber leaves powder kinetics isotherm ion exchange desorption

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Creation of Super Long Transversely Polarized Optical Needle Using Azimuthally Polarized multi Gaussian Beam

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Chinese Physics Letters 2016年第6期33卷 29-32页

作者： C.m.Sundaram k.Prabakaran P.m.Anbarasan k.B.Rajesh A.m.musthafa Department of Physics Periyar University Department of Physics Mahendra Arts and Science College(Autonomous) Department of Physics Chikkanna Government Arts College Department of General Studies(Physics Group) Jubail University College(Male Branch)Royal Commission of Jubail

The intensity distribution in the focal region of a high-na lens for the incident azimuthally polarized multi Gaussian beam transmitted through a multi belt spiral phase hologram is studied on the basis of the vector diffraction theory. Here we report a new method used to generate a needle of transversely polarized light beam with sub diffraction beam size of 0.366A that propagates without divergence over a long distance of about 22A in free space. We also expect that such a light needle of transversely polarized beam may find its applications in utilizing optical materials or instruments responsive to the transversal field only.

关键词： of on it for Creation of Super Long Transversely Polarized Optical Needle Using Azimuthally Polarized multi Gaussian Beam in that is

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Quantal studies of sodium 3p ← 3s photoabsorption spectra perturbed by ground lithium atoms

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Chinese Physics B 2019年第6期28卷 146-154页

作者： N Lamoudi F Talbi m T Bouazza m Bouledroua k Alioua Badji mokhtar University B.P.12 AnnabaAlgeria Laboratoire LESImS Laboratoire de Physique des Rayonnements Laboratoire LAmA Souk-Ahras University Souk-Ahras 41000Algeria

The pressure broadening in the far wings, where the sodium.na(3 p ← 3 s) resonance line is perturbed by ground lithium Li(2 s) atoms, has been theoretically analyzed. The naLi potential–energy curves and the transition dipole moments are constructed by using a reliable ab initio data points to carry out the reduced-absorption coefficients k_r(ν, T). This quantum-mechanical investigation have demonstrated that the naLi profile spectra show a satellite future in the red wing at wavelength λ = 685 nm in the temperature range 4000 k–1.8 × 10~4 k. The computation could also exhibit a second satellite, in the blue wing, near the wavelength λ = 574 nm beyond 6000 k and a third peak located at λ = 490 nm which begins to appear at 1.8 × 10~4 k.

关键词： pressure broadening absorption coefficient satellite structure radiative lifetime

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Update on mayer—Rokitansky—küster—Hauser syndrome

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Frontiers of medicine 2022年第6期16卷 859-872页

作者： na Chen Shuang Song Xinmiao Bao Lan Zhu national Clinical Research Center for Obstetric and Gynecologic Diseases Department of Obstetrics and GynecologyState Key Laboratory of Complex Severe and Rare DiseasesPeking Union Medical College HospitalPeking Union Medical College and Chinese Academy of Medical SciencesBeijing100730China Peking Union medical College M.D.ProgramBeijing100730China

This review presents an update of mayer—Rokitansky—küster—Hauser(mRkH)syndrome on its etiologic,clinical,diagnostic,psychological,therapeutic,and reproductive *** etiology of mRkH syndrome remains unclear due to its intrinsic *** and genetic causes that may interact during the embryonic development have been proposed with no definitive etiopathogenesis *** proportion of concomitant extragenital malformations varies in different studies,and the discrepancies may be explained by ethnic *** addition to physical exam.nation and pelvic ultrasound,the performance of pelvic magnetic resonance imaging is crucial in detecting the presence of rudimentary uterine *** syndrome has long-lasting psychological effects on patients,resulting in low esteem,poor coping strategies,depression,and anxiety *** psychological counseling and peer support to diagnosed patients is *** and timely psychological intervention could significantly improve a patient’s *** nonsurgical and surgical methods have been suggested for treatment of mRkH *** to the high success rate and minimal risk of complications,vaginal dilation has been proven to be the first-line *** is the second-line option for patients experiencing dilation *** transplantation and gestational surrogacy are options for women with mRkH syndrome to achieve biological motherhood.

关键词： mRkH(mayer-Rokitansky-küster-Hauser)syndrome etiology clinical characteristic diagnosis treatment psychological effect

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