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Ramet Population Structure of Fargesia nitida （Mitford） Keng f. et Yi in Different Successional Stands of the Subalpine Coniferous Forest in Wolong Nature Reserve

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Journal of Integrative Plant Biology 2006年第10期48卷 1147-1153页

作者： Xiao-Hong Yu jian-ping tao Yuan Li Yong-jian Wang Yi Xi Wei-Yin Zhang Run-Guo Zang Key Laboratory of Eco-environments of Three Gorges Reservoir Region Ministry of Education School of Life Sciences Southwest University Chongqing 400715 China Institute of Forest Ecology Environment and Protection Chinese Academy of Forestry Beijing 100091 China

Forest structure and succession in Wolong Nature Reserve is influenced by the understory dwarf bamboo population. However, less is known about how the forest succession affects the dwarf bamboo population. To examine the bamboo ramet population growth of Fargesla nitida （Mltford） Keng f. et Yi and to determine how ramet population structure varies along the succession of coniferous forest, we sampled ramet populations of F. nitida from the following three successional stages：（i） a deciduous broad-leaved （BL） stand; （ii） a mixed broad-leaved coniferous （MI） stand; and （ill） a coniferous （CF） stand. We investigated the population structure, biomass allocation, and morphological characteristics of the bamboo ramet among the three stand types. Clonal ramets, constituting the bamboo population, tended to become short and small with succession. The ramet changed towards having a greater mass investment in leaves, branches and underground roots and rhizomes rather than in the culm. With respect to leaf traits, individual leaf mass and area in the BL stand were markedly bigger than those In both the MI and CF stands, except for no significant difference in specific leaf area. The age distribution showed that the bamboo population approached an older age with succession. The results demonstrate that the ramet population structure of F. nitida is unstable and its growth performance is inhibited by succession.

关键词： coniferous forest Fargesia nitida ramet population structure succession Wolong Nature Reserve

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Formation mechanism of fault accommodation zones under combined stress in graben basin:Implications from geomechanical modeling

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Petroleum Science 2024年第1期21卷 54-76页

作者： Qi-Qiang Ren Jin-Liang Gao Rong-tao jiang Jin Wang Meng-ping Li jian-Wei Feng Institute of Sedimentary Geology Chengdu University of TechnologyChengdu 610059SichuanChina PetroChina Research Institute of Petroleum Exploration and Development Beijing100083China jianghan Oilfield Oil and Gas Production Capacity Construction Management Center Chongqing408000China Sinopec Chongqing Fuling Shale Gas Exploration and Development Company Chongqing408000China College of Energy Chengdu University of TechnologyChengdu 610059SichuanChina School of Geoscience China University of Petroleum(East China)Qingdao 266580ShandongChina

A fault accommodation zone is a type of structure that is defined as regulating displacement and strain between faults *** numbers of fault accommodation zones are being identified in graben basins,indicating the potential exploration target and petroleum accumulation *** study aims to analyze the formation mechanism and development of fault accommodation zones under combined stress by a numerical simulation method considering geomechanical *** three-dimensional(3-D)seismic interpretation and fractal dimension method,exampled with the Dongxin fault zone,the fault activity and fault combination pattern were conducted to quantitatively characterize the activity difference in fault accommodation *** with mechanical experiment test,a geomehcanical model was established for fault accommodation zones in a graben *** the paleostress numerical simulations and structural physical simulation experiment,the developmental characteristics and genetic mechanism of fault accommodation zones were *** by multi movements and combined stresses,three significant tectonic evolution stages of the Dongxing Fault Zone(DXFZ)were distinguished:During the E_(s)^(3)sedimentary period,the large difference in the stress,strain,and rupture distribution in various faults were significant,and this stage was the key generation period for the prototype of the DXFZ,including the FAZ between large-scale *** the E_(s)^(2)sedimentary period,the EW-trending symmetric with opposite dipping normal faults and the NE-SW trending faults with large scale were furtherly *** junction area of two secondary normal faults were prone to be ruptured,performing significant period for inheriting and developing characteristics of fault accommodation *** the Es1 sedimentary period,the high-order faults in the DXFZ exhibited the obvious fault depressions and strike-slip activity,and the fault accommodation zones were

关键词： Fault accommodation zone Graben basin Fault activity Tectonic physical simulation experiment Finite element numerical simulation Dongxin fault zone

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Manipulating the Phase Transition Behavior of Dual Temperature-Responsive Block Copolymers by Adjusting Composition and Sequence

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Chinese Journal of Polymer Science 2024年第2期42卷 176-187,I0006页

作者： Zhi Zou Xiang Xu Hai-tao Zhao jian-Nan Cheng Wei-Wei He Li-Fen Zhang Zhen-ping Cheng Suzhou key Laboratory of Macromolecular Design and Precision Synthesis Jiangsu Key Laboratory of Advanced Functional Polymer Design and ApplicationState and Local Joint Engineering Laboratory for Novel Functional Polymeric MaterialsCollege of ChemistryChemical Engineering and Materials ScienceSoochow UniversitySuzhou215123China State Key Laboratory of Radiation Medicine and Protection School for Radiological and Interdisciplinary Sciences(RAD-X)and Collaborative Innovation Center of Radiation Medicine of JiangsuSoochow UniversitySuzhou215123China

Temperature-responsive polymers have garnered significant attention due to their ability to respond to external *** this work,dual temperature-responsive block copolymers are synthesized via reversible addition-fragmentation chain transfer polymerization(RAFT)polymerization utilizing zwitterionic monomer methacryloyl ethyl sulfobetaine(SBMA) and N-isopropyl acrylamide(NIPAAm) as *** thermal responsive behaviors can be easily modulated by incorporating additional hydrophobic monomer benzyl acrylate(BN) or hydrophilic monomer acrylic acid(AA),adjusting concentration or pH,or varying the degree of polymerization of the block chain *** cloud points of the copolymers are determined by UV-Vis spectrophotometry,and these copolymers exhibit both controlled upper and lower critical solu bility temperatures(LCST and UCST) in aqueous *** study analyzes and summarizes the influencing factors of dual temperature responsive block copolymers by exploring the effects of various conditions on the phase transition temperature of temperature-sensitive polymers to explore the relationship between their properties and environment and structure to make them more selective in terms of temperature application range and regulation *** is very interesting that the introduction of poly-acrylic acid(PAA) segments in the middle of di-block copolymer PSBMA_(55)-b-PNIPAAm_(80) to form PSBMA_(55)-b-PAA_(x)-b-PNIPAAm_(80) results in a reversal of temperature-responsive behaviors from 'U'(LCST UCST) type,while the copolymer PSBMA_(55)-b-P(NIPAAm_(80)-co-AA_(x)) *** work provides a clue for tuning the phase transition behavior of polymers for manufacture of extreme smart materials.

关键词： Temperature responsive polymers High critical solubility temperature(UCST) Low critical solubility temperature(LCST) Block copolymers

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A new liquid membrane diffusion model for characterizing the adsorption kinetics of europium by using a continuous measurement of adsorption platform

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Nuclear Science and Techniques 2024年第1期35卷 59-72页

作者： Hao-Qi Yu tao Yu jian-Hua Ye State Key Laboratory of Nuclear Resources and Environment East China University of TechnologyNanchang 330013China CGN Cangnan Nuclear Power Co. Ltd.Cangnan 325800China jiangxi Province Key Laboratory of Polymer Micro/Nano Manufacturing and Devices East China University of TechnologyNanchang 330013China School of Nuclear Science and Engineering East China University of TechnologyNanchang 330013China

To explore the kinetic adsorption under continuous and nonequilibrium states, an integration of continuous measurement and adsorption platform kinetics method was proposed, which was initially called the ICM-AP kinetics method, and a corresponding kinetic adsorption experimental method was developed. Adsorption experiments of europium(Eu) on Ca-bentonite,Na-bentonite, and the D231 cation exchange resin were performed using the ICM-AP kinetics method and continuous measurements. Because the kinetic experimental results observed in this study were different from those of traditional batch adsorption data, pseudo-first-order or pseudo-second-order kinetic models were unsuitable for fitting the experimental ***, a liquid membrane diffusion(LMD) model was developed based on the assumption of simultaneous adsorption/desorption to discuss the mechanism of kinetic adsorption. The kinetic adsorption mechanism was also studied by using *** results indicated that the proposed adsorption model can fit the experimental data more suitably, and the adsorption/desorption behaviors of Eu on bentonite and the D231 resin were simultaneously observed, suggesting that the adsorption kinetics of Eu(Ⅲ) was mainly dominated by hydrated Eu(Ⅲ) ions on the liquid membrane.

关键词： ICM-AP method LMD model Adsorption mechanism Eu(Ⅲ)

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Correlation between fragmented QRS and the short-term prognosis of patients with acute myocardial infarction

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Journal of Zhejiang University-Science B(Biomedicine & Biotechnology) 2014年第1期15卷 67-74页

作者： Qin-hui SHENG Chih-Chi HSU jian-ping LI tao HONG Yong HUO Department of Cardiology Peking University First Hospital Beijing 100034 China

This study is aimed to investigate the clinical significance and the short-term prognostic value of frag- mented QRS （fQRS） for patients with acute myocardial infarction （AMI）. Three hundred patients with AMI were tested with retrospective analysis on the patients＇ clinical information, hospitalized treatment, fQRS onset time, location of lesions, and other relevant data, in order to assess the relationship between the presence of fQRS and its prognosis. The rates of malignant cardiac arrhythmia, left ventricular systolic dysfunction （LVSD）, and mortality in the positive fQRS group were 13.6%, 29.2%, and 23.7%, respectively, with all showing a p value 〈0.05. For the ST segment elevation myocardial infarction （STEMI） subgroup, all the rates showed significant differences with a p value 〈0.01, while for the non-STEMI （NSTEMI） subgroup showed no significant differences. In patients with a positive fQRS, there were no differences in malignant cardiac arrhythmia between patients with and without percutaneous coronary in- tervention （PCI）（p〉0.05）. As for the LVSD and mortality, the p values between patients with and without PCI were 0.031 and 0.000, respectively, suggesting statistical significance. The results imply that AMI patients with positive fQRS especially for the patients with STEMI had higher rates of malignant cardiac arrhythmia, LVSD, and mortality than the non-fQRS group. Patients of AMI with positive fQRS, who underwent early revascularization, could lower the incidence of the cardiovascular event. In addition, the presence of fQRS could be used as an indication of early in- tervention treatment for patients.

关键词： Fragmented QRS Acute myocardial infarction Short-term prognosis

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High-precision analytical solutions for Earth coverage of constellation equipped with reentry glide vehicles

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CHINESE JOURNAL OF AERONAUTICS 2024年第9期37卷 385-398页

作者： Ma, ping Sun, Weibo Gao, Jie Chao, tao Harbin Inst Technol Control & Simulat Ctr Harbin 150001 Peoples R China Beijing Inst Spacecraft Syst Engn Beijing 100094 Peoples R China

To efficiently and accurately design satellite constellations equipped with Reentry Glide Vehicles (RGVs), new analytical solutions are developed for calculating their coverage performance. Specifically, a new coverage model is established by approximating the Reentry Reachable Domain (RRD). However, the computation of real-time relative distances between satellites and targets, which is essential for coverage analysis based on this model, imposes a significant computational burden. To address this challenge, a coverage analysis method based on two-dimensional map theory is proposed. This method represents the coverage conditions of a target as a fixed area on a two-dimensional map and transforms the satellite trajectory into a series of parallel lines. By determining the intersection points between these lines and the area boundaries, the coverage analytical solutions for a target point are derived. On this basis, coverage theorems are presented for rapid calculation of the constellation coverage performance for an area. Simulation results demonstrate the effectiveness and high precision of the proposed analytical solutions. (c) 2024 Production and hosting by Elsevier Ltd. on behalf of Chinese Society of Aeronautics and Astronautics. This is an open access article under the CC BY-NC-ND license (http://***/ licenses/by-nc-nd/4.0/).

关键词： Analytical solutions Reentry glide vehicle Reentry reachable domain Two-dimensional map Constellation GENERAL-ANALYSIS METHOD SATELLITE CONSTELLATION ROUTE THEORY DISCONTINUOUS COVERAGE GEOMETRIC ANALYSIS DESIGN FUNDAMENTALS ORBITS

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Single-atom Rh catalysts for efficiently degrading Rhodamine B with high concentration

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Rare Metals 2024年第5期43卷 2331-2338页

作者： Shou-Yao Hu jian-ping Guan Run-Ze Ma Yu tao Dong-Hao Liu Jia-Xin Gong Yu Xiong Department of Chemistry and Chemical Engineering Central South UniversityChangsha 410083China

Highly concentrated dye wastewater has a serious effect on the quality of natural waters;thus,developing novel catalysts to degrade dyes rapidly and efficiently is of great *** the first time,this study reports an Rh single atom loaded on a nitrogen-doped carbon(SA-Rh/CN)*** catalyst exhibits an excellent processing capacity for high concentrations of Rhodamine B(Rh B),high catalytic activity(95.7% degradation of Rh B in60 min)and excellent stability(93.5% degradation efficiency after 10 stable runs).

关键词： catalyst. catalysts loaded

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Data-Driven Active Disturbance Rejection Control of Plant-Protection Unmanned Ground Vehicle Prototype: A Fuzzy Indirect Iterative Learning Approach

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IEEE/CAA Journal of Automatica Sinica 2024年第8期11卷 1892-1894页

作者： tao Chen Ruiyuan Zhao jian Chen Zichao Zhang College of Engineering China Agricultural UniversityBeijing 100083China Key Laboratory of Smart Agricultural Technology in Tropical South China Ministry of Agriculture and Rural AffairsGuangzhou 510642China

Dear Editor,This letter proposes a fuzzy indirect iterative learning(FIIL)active disturbance rejection control(ADRC)scheme to address the impact of uncertain factors of plant-protection unmanned ground vehicle(UGV),in which ADRC is a data-driven model-free control algorithm that only relies on the input and output data of the *** on the established nonlinear time-varying dynamic model including dynamic load(medicine box),the FIIL technology is adopted to turn the bandwidth and control channel gain online,in which the fuzzy logic system is used to update the gain parameters of iterative learning in real *** and experiment show the FIIL-ADRC scheme has better control performance.

关键词： Active scheme iterative

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Accurate simulations of pure-viscoacoustic wave propagation in tilted transversely isotropic media

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Petroleum Science 2024年第2期21卷 866-884页

作者： Qiang Mao jian-ping Huang Xin-Ru Mu Ji-Dong Yang Yu-jian Zhang Geosciences Department China University of Petroleum(East China)Qingdao266580ShandongChina Pilot National Laboratory for Marine Science and Technology(Qingdao) Qingdao266207ShandongChina

Forward modeling of seismic wave propagation is crucial for the realization of reverse time migration(RTM) and full waveform inversion(FWI) in attenuating transversely isotropic media. To describe the attenuation and anisotropy properties of subsurface media, the pure-viscoacoustic anisotropic wave equations are established for wavefield simulations, because they can provide clear and stable wavefields. However, due to the use of several approximations in deriving the wave equation and the introduction of a fractional Laplacian approximation in solving the derived equation, the wavefields simulated by the previous pure-viscoacoustic tilted transversely isotropic(TTI) wave equations has low accuracy. To accurately simulate wavefields in media with velocity anisotropy and attenuation anisotropy, we first derive a new pure-viscoacoustic TTI wave equation from the exact complex-valued dispersion formula in viscoelastic vertical transversely isotropic(VTI) media. Then, we present the hybrid finite-difference and low-rank decomposition(HFDLRD) method to accurately solve our proposed pure-viscoacoustic TTI wave equation. Theoretical analysis and numerical examples suggest that our pure-viscoacoustic TTI wave equation has higher accuracy than previous pure-viscoacoustic TTI wave equations in describing q P-wave kinematic and attenuation characteristics. Additionally, the numerical experiment in a simple two-layer model shows that the HFDLRD technique outperforms the hybrid finite-difference and pseudo-spectral(HFDPS) method in terms of accuracy of wavefield modeling.

关键词： Pure-viscoacoustic TTI wave equation Attenuation anisotropy Seismic modeling Low-rank decomposition method

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Control of fine particulate nitrate during severe winter haze in“2+26”cities

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Journal of Environmental Sciences 2024年第2期136卷 261-269页

作者： Chuang Qin Xiao Fu tao Wang jian Gao Jiaqi Wang Institute of Environment and Ecology Tsinghua Shenzhen International Graduate SchoolTsinghua UniversityShenzhen 518055China Department of Civil and Environmental Engineering Hong Kong Polytechnic UniversityHong Kong 99907China State Key Laboratory of Environmental Criteria and Risk Assessment Chinese Research Academy of Environmental SciencesBeijing 10084China

The“2+26”cities,suffering the most severe winter haze pollution,have been the key region for air quality improvement in *** prominent nitrate pollution is one of the most challenging environmental issues in this region,necessitating development of an effective control ***,we use observations,and state-of-the-art model simulations with scenario analysis and process analysis to quantify the effectiveness of the future SO_(2)-NO_(X)-VOC-NH_(3) emission control on nitrate pollution mitigation in“2+26”*** on a serious winter haze episode,we find that limited NO_(X)emission reduction alone in the short-term period is a less effective choice than VOC or NH_3emission reduction alone to decrease nitrate concentrations,due to the accelerated NO_(X)-HNO_(3)conversion by atmospheric oxidants and the enhanced HNO_(3)to NO_(3)^(-)partition by ammonia,although deep NO_(X)emission reduction is essential in the long-term *** synergistic NH_(3) and VOC emission control is strongly recommended,which can counteract the adverse effects of nonlinear photochemistry and aerosol chemical feedback to decrease nitrate *** extra benefits will be reduced if the synergistic NH_(3) and VOC reduction is delayed,and thus reducing emission of multiple precursors is urgently required for the effective control of increasingly severe winter nitrate pollution in“2+26”cities.

关键词： Nitrate Winter haze pollution Emission reduction “2+26”cities

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