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Phylogenetic and functional structures of succession in plant communities on mounds of Marmota himalayana in alpine regions on the northeast edge of the QinghaieTibet Plateau

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Plant Diversity 2021年第4期43卷 275-280页

作者： Xinhui Li Tao yang Dandan wang Guizhou University of Traditional Chinese Medicine Guiyang550025China College of Ecology and Environment Yunnan UniversityKunming650504China

Few studies have examined the succession of plant communities in the alpine *** the succession of plant communities is helpful to understand how species diversity is formed and *** this study,we used species inventories,a molecular phylogeny,and trait data to detect patterns of phylogenetic and functional community structure in successional plant communities growing on the mounds of Himalayan marmots(Marmota himalayana)on the southeast edge of the Qinghai-Tibet *** found that phylogenetic and functional diversities of plant communities on marmot mounds tended to cluster during the early to medium stages of succession,then trended toward overdispersion from medium to late *** species in early and late stages of succession were phylogenetically and functionally overdispersed,suggesting that such communities were assembled mainly through species interactions,especially *** the medium and late stages of succession,alpine communities growing on marmot mounds were phylogenetically and functionally clustered,implying that the communities were primarily structured by environmental *** the medium and late stages of succession the phylogenetic and functional structures of plant communities on marmot mounds differed significantly from those on neighboring *** results indicate that environmental filtering and species interactions can change plant community composition at different successional *** of plant communities on marmot mounds was promoted by a combination of traits that may provide advantages for survival and adaptation during periods of environmental change.

关键词： Community succession Marmota himalayana Phylogenetic structure Functional structure QinghaieTibet Plateau

Facile Solid-State Synthesis Route to Metal Nitride Nanoparticles

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Journal of Materials Science & Technology 2008年第5期24卷 737-741页

作者： Yinxiao DU Ming LEI Hui yang Department of Mathematics and Physics Zhengzhou Institute of Aeronautical Industry Management Zhengzhou 450015 China Beijing National Laboratory for Condensed Matter Physics Institute of Physics Chinese Academy of Sciences Beijing 100080 China

By a facile and efficient solid-state reaction route using an organic reagent cyanamide （CN2H2） as a precursor with another one being metal oxides, we successfully synthesized seven technologically important metal nJtrJdes including cubic VN, CrN, NbN, hexagonal GaN, AIN, BN, and wN at moderate temperatures. The experimental results show that cyanamide （CN2H2） is a powerfully reducing and nitridizing reagent and the metal oxides are completely converted into the corresponding nitride nanoparticles at lower temperatures than that reported in the conventional methods. It is found that EN2H2 can exhibit some interesting condensation processes, and the final products, highly active carbon nitride species, play a crucial role in the reducing and nitridizing processes.

关键词： Nitride Cyanamide Solid-state reaction Nanoparticles

Sulfate-Methane Transition Depths and Its Implication for Gas Hydrate

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Journal of Ocean University of China 2020年第4期19卷 837-842页

作者： ZHANG yang LI Guangxue GAO Xinghua Key Laboratory of Submarine Sciences and Prospecting Techniques Ministry of Educationand College of Marine GeosciencesOcean University of ChinaQingdao 266100China

The biological removal of CH4 by methanotrophic(CH4-oxidizing)archaea always occurs at a distinct zone which is known as sulfate-methane transition zone(SMTZ).It is an important indication for high methane flux and gas hydrate *** this study,we collected pore-water data from South China Sea,Carolina Rise and Blake Ridge to analyze the relationship between CH4,SO42−concentration and *** found that below the SMTZ,the methane concentration increases continuously with depth and sulfate concentration decrease linearly to *** addition,the geochemical data taken from all these sites show that SMTZ is relatively shallow(less than 20 m),which may indicate that these areas have high methane flux.

关键词： gas hydrate sulfate-methane transition zone(SMTZ) anaerobic methane oxidation(AMO) South China Sea Carolina Rise and Blake Ridge

To curve for survival:Apical hook development

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Journal of Integrative Plant Biology 2023年第2期65卷 324-342页

作者： Yichuan wang yang Peng Hongwei Guo Department of Biology School of Life SciencesKey Laboratory of Molecular Design for Plant Cell Factory of Guangdong Higher Education InstitutesInstitute of Plant and Food ScienceSouthern University of Science and Technology(SUSTech)Shenzhen 518055China

Apical hook is a simple curved structure formed at the upper part of hypocotyls when dicot seeds germinate in *** hook structure is transient but essential for seedlings’survival during soil emergence due to its efficient protection of the delicate shoot apex from mechanical *** a superb model system for studying plant differential growth,apical hook has fascinated botanists as early as the Darwin age,and significant advances have been achieved at both the morphological and molecular levels to understand how apical hook development is ***,we will mainly summarize the research progress at these two *** will also briefly compare the growth dynamics between apical hook and hypocotyl gravitropic bending at early seed germination phase,with the aim to deduce a certain consensus on their ***,we will outline the remaining questions and future research perspectives for apical hook development.

关键词： apical hook auxin gradient differential growth HOOKLESS1 phytohormones

Inhibition roles of molybdate and borate on Q235 steel corrosion in resistance reducing agent

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Journal of Iron and Steel Research International 2023年第8期30卷 1477-1489页

作者： yang yang Hui Su Lan-lan Liu Song Xu Zhen Zhong Xiao-bao Zhou Tang-qing wu School of Materials Science and Engineering Xiangtan UniversityXiangtan 411105HunanChina State Grid Hunan Electric Power Company Limited Transmission Maintenance Changsha 410100HunanChina State Grid Hunan Electric Power Company Limited Research Institute Changsha 410007HunanChina

The effects of Na_(2)MoO_(4) and Na_(2)B_(4)O_(7) on corrosion behavior of Q235 steel in resistance reducing agent(RRA)containing sodium bentonite were studied by mass loss,scanning electron microscopy and electrochemical *** results showed that both the independent and mixed additions of Na_(2)MoO_(4) and/or Na_(2)B_(4)O_(7),can reduce the corrosion rate of Q235 steel in RRA containing sodium *** the inhibition effect of Na_(2)MoO_(4) and/or Na_(2)B_(4)O_(7)increased with their dosage *** the same dosage,the inhibition efficiency of the mixed addition of Na_(2)MoO_(4) and Na_(2)B_(4)O_(7),was higher than that of their independent *** passivation effect of Q235 steel was easy to obtain in the RRA with the mixed addition of Na_(2)MoO_(4) and Na_(2)B_(4)O_(7).The optimized inhibitor for the RRA containing sodium bentonite was the mixture of Na_(2)B_(4)O_(7) and Na_(2)MoO_(4) with a total concentration of 1.5 wt.%.Furthermore,the increase in corrosion potential E_(corr) and the decrease in corrosion current density i_(cor) in carbon steel were one of the important criteria for the formation of passivation film.

关键词： Q235 steel Resistance reducing agent Corrosion inhibitor Sodium bentonite Electrochemical impedance spectrum

ELECTROREDUCTION　OF　Zn^2＋　AND　Ni^2＋　AND　Cu^2＋　IN　UREA－CHLORIDES　MELT

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中国有色金属学会会刊：英文版 1996年第2期6卷 41-44,52页

作者： Liu, Peng yang, Qiqin Liu, Guankun Department of Chemistry Zhongshan University Guangzhou 510275 China

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关键词： urea-chlorides melt, electroreduction of Zn￣(2+), Ni￣(2+) and Cu￣(2+) diffusion coefficient transfer coefficient

Effect of Electromagnetic Compound Treatment on Microstructure and Performance of Cemented Carbide

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Journal of wuhan University of Technology(Materials Science) 2019年第5期34卷 1119-1126页

作者： wEI Liao yang Yi yang Gang wU Mingxia wEI Can wUXiuli School of Mechanical Engineering Sichuan University Chengdu 610065China College of Arts and Sciences Guangxi Radio and TV UniversityNanning 530022China

In order to study the effect of electromagnetic compound treatment on the mechanical property, cutting performance and microstructure of cemented carbide, the samples were treated by a self-made electromagnetic compound treatment device with different magnetic field strength(H=1, 1.25 and 1.5 T). The electromagnetic compound treatment method was proposed to couple pulsed magnetic field and pulsed current. The results show that after the pulsed magnetic field treatment, the values of the transverse rupture strength of the samples were respectively reduced by 21%, 20.6% and 20.1%;the cutting performance was decreased by about 4.5%, which means the tool life was decreased. After the electromagnetic compound treatment, the values of the transverse rupture strength of the rectangular samples were respectively increased by 8%, 8.6% and 9.5%, and the tool life was increased by 4.2%, 7% and 10.3%. After the electromagnetic compound treatment, the pulse current provided the driving force for dislocation motion. A strong pulse current driving force is more likely to make the dislocation multiply and slip. A high density dislocation cell is formed within the material, so the mechanical properties were significantly increased.

关键词： cemented carbide magnetic field treatment electromagnetic compound treatment microstructure/performance

Nuclear volume effects in kinetic isotope fractionation:A case study of mercury oxidation by chlorine species

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Acta Geochimica 2024年第3期43卷 411-423页

作者： Chenlu yang Yining Zhang Yun Liu Research Center for Planetary Science College of Earth and Planetary SciencesChengdu University of TechnologyChengdu 610059China State Key Laboratory of Ore Deposit Geochemistry Institute of GeochemistryChinese Academy of SciencesGuiyang 550081China

It is well-known that the equilibrium isotope fractionation of mercury(Hg)includes classical massdependent fractionations(MDFs)and nuclear volume effect(NVE)induced mass-independent fractionations(MIFs).However,the effect of the NVE on these kinetic processes is not *** total fractionations(MDFs+NVEinduced MIFs)of several representative Hg-incorporated substances were selected and calculated with ab initio calculations in this work for both equilibrium and kinetic ***-induced MIFs were calculated with scaled contact electron densities at the nucleus through systematic evaluations of their accuracy and errors using the Gaussian09 and DIRAC19 packages(named the electron density scaling method).Additionally,the NVE-induced kinetic isotope effect(KIE)of Hg isotopes are also calculated with this method for several representative Hg oxidation reactions by chlorine *** KIEs for 202 Hg/^(198)Hg ranging from−2.27‰to 0.96‰are *** anomalous^(202)Hg-enriched KIEs(δ^(202)Hg/^(198)Hg=0.83‰,0.94‰,and 0.96‰,)caused by the NVE are observed,which are quite different from the classical view(i.e.,light isotopes react faster than the heavy ones).The electron density scaling method we developed in this study can provide an easier way to calculate the NVE-induced KIEs for heavy isotopes and serve to better understand the fractionation mechanisms of mercury isotope systems.

关键词： Nuclear volume effect Kinetic fractionation Hg isotopes Ab initio calculations

DEEP RELU NETwORKS OVERCOME THE CURSE OF DIMENSIONALITY FOR GENERALIZED BANDLIMITED FUNCTIONS

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Journal of Computational Mathematics 2021年第6期39卷 801-815页

作者： Hadrien Montanelli Haizhao yang Qiang Du Centre de Mathematiques Appliquees Ecole PolytechniquePalaiseauFrance Department of Mathematics Purdue UniversityIndianaUnited States Department of Applied Physics and Applied Mathematics Columbia UniversityNew YorkUnited States

we prove a theorem concerning the approximation of generalized bandlimited multivariate functions by deep ReLU networks for which the curse of the dimensionality is *** theorem is based on a result by Maurey and on th... 详细信息

关键词： Machine learning Deep ReLU networks Curse of dimensionality Approximation theory Bandlimited functions Chebyshev polynomials