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Degradation of Populus euphratica community in the lower reaches of the Tarim River, Xinjiang, China

Journal of Environmental Sciences 2005年第5期17卷 740-747页

作者： liU Jia-zhen CHEN Ya-ning CHEN yong-jin ZHANG Na li Wei-hong Xinjiang Institnte of Ecology and Geography Chinese Academy of Sciences Urumqi 830011 China Graduate School of Chinese Academy of Sciences Beijing 100039 China

To investigate the relationships between the degradation of plant community and groundwater level in the lower reaches of the Tarim River, nine monitored sections were set along the main stream, where there had been no runoff for nearly 30 years. The characteristics of plant communities were analyzed. It was found that the coverage of trees gradually decreased along the groundwater depth gradient, while the coverage of shrubs slightly increased rather than decreased at first and then gradually decreased, and the coverage of herbs steadily decreased at the beginning and then quickly decreased. The species diversity and species richness of both herbs and woody plants showed obvious degrading trends, while the variations in species evenness were slight. The degrading sequences of species were related to their physiological and ecological characteristics, especially their sensitivity to changes of groundwater table. The herbs with shallow roots first degenerated or disappeared when the groundwater table fell, and then did the deep-rooted herbs, and finally the trees and shrubs with strong tolerance to drought degenerated. The Populus euphratica communities showed typical degrading characteristics, namely the dominant species Populus euphratica remained its dominant status during the degradation. Overall, the existence of strongly tolerant-drought species was the obvious indication of plant species degradation; while simplification of community structure and the decrease of species richness were the obvious indication of plant community degradation.

关键词： degradation plant community coverage species diversity Tarim River

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Two New Isosteroid Alkaloids from Fritillaria monatha Migo（Ⅲ）

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Chinese Chemical Letters 2006年第5期17卷 631-634页

作者： Hong ning liU Fei li yong Ming LUO Wei Feng ZHU Jiangxi University of Traditional Chinese Medicine Nanchang 330004

Two new isosteroid alkaloids, named pengbeimine A and pengbeimine C, were isolated from the fresh bulbs of FritiUaria monatha Migo. Their structures were determined by spectral methods, and were proved by X-ray diffra... 详细信息

关键词： Fritillaria monatha Migo isosteroid alkaloids pengbeimine A pengbeimine C.

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Giant bilateral scrotal lipoma with abnormal somatic fat distribution:A case report

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World Journal of Clinical Cases 2022年第29期10卷 10803-10810页

作者： Yu Chen Xiu-ning li Xian-lin Yi yong Tang Department of Urology Wuming Hospital of Guangxi Medical UniversityNanning 530199Guangxi Zhuang Autonomous RegionChina

BACKGROUND Scrotal lipoma is exceedingly rare,so its origin is still *** is suggested as a potential factor,but the cause remains *** is difficult to determine the origin of these *** studies have suggested that these tumours may be congenital or that they originate from small fatty particles around the *** studies have suggested that these tumours originate from testicles or the *** SUMMARY A 66-years elderly male with giant scrotal mass.B-ultrasound,computed tomography and magnetic resonance imaging examinations are typical lipomalike changes,which were confirmed by postoperative pathological *** somatic fat distribution was confirmed by *** recurrence after follow-up for 2 *** published English-language literature was reviewed,and a history of inguinal or pelvic surgery was reported in 6 studies(total 21 cases).To our knowledge,this is the heaviest bilateral scrotal lipoma in the English-language literature,and it has the longest postoperative follow-up *** importantly,the origin of these tumours is reviewed and *** Giant bilateral scrotal lipoma in elderly may as part of the symptoms of abnormal somatic fat distribution.

关键词： lipoma Crotum Bilateral Extratesticular tumour Fat distribution Case report

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Steroidal alkaloids from the bulbs of Fritillaria monatha

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Chinese Chemical Letters 2008年第5期19卷 544-546页

作者： Hong ning liu Fei li yong Ming Luo Wei Feng Zhu Jiangxi University of Traditional Chinese Medicine Nanchang 330004 China

Two new Steroidal alkaloids, named pengbeisine A and pengbeisine B, were isolated from the fresh bulbs of Fritillaria monatha Migo. along with a known alkaloid. The structures were characterized as 22,26-imino-17, 23-oxido-5α-jerv-6-oxo-2α,3β-diol and 22, 26-imino-17, 23-oxido-5α-jerv-6-oxo-2β,3α-diol on the basis of spectroscopic methods.

关键词： Fritillaria monatha Migo Steroidal alkaloids Pengbeisine A Pengbeisine B

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Phosphate removal from wastewater by model-La(Ⅲ)zeolite adsorbents

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Journal of Environmental Sciences 2008年第6期20卷 670-674页

作者： ning Ping BART Hans-Jorg li Bing LU Xiwu ZHANG yong Department of Environmental Science and Engineering Kunming University of Science and Technology Kunming 650093 China Lehrsmhl für Thermische Verfahrenstechnik TU Kaiserslautern D-67653 Kaiserslautern Germany Department of Environmental Engineering Southeast University Nanjing 210096 China

Phosphorus is one of the primary nutrients which leads to eutrophication and accelerates aging process in enclosed water bodies. Because of the poor phosphorus selectivity of other adsorbents, the novel La（Ⅲ）-modified zeolite adsorbent （LZA） was prepared by modifying 90 nm zeolite with lanthanide to selectively remove phosphate in the presence of various omnipresent anions, such as sulfates, bicarbonates, and chlorides. Through batch and fixed bed operation, the following optimum conditions were obtained： concentration of lanthanum chloride solution 0.05 mol/L; solid/liquor ratio 1/25; pH 10; calcination temperature 550℃; time 1 h. The value of the Freundlich model constants Kf and 1/n were found to be 16.76 mg/L and 0.2209, respectively. In addition, when calculated at pH 6.0, distribution coefficient KD could be as high as 36.6. Furthermore, in the alkaline pH range, solution of 0.8 mol/L NaCl was used to regenerate the saturated LZA, which could reach the high regeneration efficiency as high as 100%. Because of the good selectivity and regenerability of LZA, it might serve as a potential way for advanced phosphate removal from the sewage containing other anions.

关键词： phosphate adsorption zeolite regeneration distribution coefficient

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Correlation between the rock mass properties and maximum horizontal stress:A case study of overcoring stress measurements

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International Journal of Minerals,Metallurgy and Materials 2025年第1期32卷 39-48页

作者： Peng li Meifeng Cai Shengjun Miao Yuan li Yu Wang Key Laboratory of Ministry of Education for Efficient Mining and Safety of Metal Mines University of Science and Technology BeijingBeijing 100083China State Key Laboratory of Coal Resources and Safe Mining China University of Mining and TechnologyXuzhou 221116China

Understanding the mechanical properties of the lithologies is crucial to accurately determine the horizontal stress *** investigate the correlation between the rock mass properties and maximum horizontal stress,the three-dimensional(3D)stress tensors at 89 measuring points determined using an improved overcoring technique in nine mines in China were adopted,a newly defined characteristic parameter C_(ERP)was proposed as an indicator for evaluating the structural properties of rock masses,and a fuzzy relation matrix was established using the information distribution *** results indicate that both the vertical stress and horizontal stress exhibit a good linear growth relationship with *** is no remarkable correlation between the elastic modulus,Poisson's ratio and depth,and the distribution of data points is scattered and ***,there is no obvious relationship between the rock quality designation(RQD)and *** maximum horizontal stress σ_(H) is a function of rock properties,showing a certain linear relationship with the C_(ERP)at the same *** addition,the overall change trend of σ_(H) determined by the established fuzzy identification method is to increase with the increase of C_(ERP).The fuzzy identification method also demonstrates a relatively detailed local relationship betweenσ_H and C_(ERP),and the predicted curve rises in a fluctuating way,which is in accord well with the measured stress data.

关键词： overcoring stress measurements elastic modulus Poisson's ratio rock quality designation maximum horizontal stress fuzzy identification

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Interfacial Zn2+-solvation regulator towards reversible and stable Zn anode

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Journal of Energy Chemistry 2025年第1期100卷 684-692页

作者： Miao Zhou Xiongbin Luo Hang li Shan Guo Zhuang Tong Xiaotao Zhou Xu li Zhaohui Hou Shuquan liang Guozhao Fang College of Mechanical Engineering Key Laboratory of Hunan Province for Advanced Carbon-based Functional Materials Hunan Institute of Science and Technology School of Materials Science and Engineering Key Laboratory of Electronic Packaging and Advanced Functional Materials of Hunan Province Central South University College of Materials and Metallurgy Guizhou University National Energy Metal Resources and New Materials Key Laboratory Central South University

Aqueous zinc-ion batteries （AZIBs） are fundamentally challenged by the instability of the electrode/electrolyte interface,predominantly due to irreversible zinc （Zn） deposition and hydrogen ***,the intricate mechanisms behind the electrochemical discrepancies induced by interfacial Zn2+-solvation and deposition behavior demand comprehensive *** molecules endowed with special functional groups （such as hydroxyl,carboxyl,etc.） have the potential to significantly optimize the solvation structure of Zn2+and regulate the interfacial electric double layer （EDL）.By increasing nucleation overpotential and decreasing interfacial free energy,these functional groups facilitate a lower critical nucleation radius,thereby forming an asymptotic nucleation model to promote uniform Zn ***,this study presents a pioneering approach by introducing trace amounts of n-butanol as solvation regulators to engineer the homogenized Zn （H-Zn） anode with a uniform and dense *** interfacial reaction and structure evolution are explored by in/ex-situ experimental techniques,indicating that the H-Zn anode exhibits dendrite-free growth,no by-products,and weak hydrogen evolution,in sharp contrast to the bare ***,the H-Zn anode achieves a remarkable Zn utilization rate of approximately 20% and simultaneously sustains a prolonged cycle life exceeding 500 ***,the H-Zn//NH4V4O10（NVO） full battery showcases exceptional cycle stability,retaining 95.04%capacity retention after 400 cycles at a large current density of 5 A *** study enlightens solvation-regulated additives to develop Zn anode with superior utilization efficiency and extended operational lifespan.

关键词： Aqueous zinc-ion batteries Interfacial reaction Asymptotic nucleation model Reversible and stable Zn anode

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An extended multiple-support response spectrum method incorporating fluid-structure interaction for seismic analysis of deep-water bridges

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Earthquake Engineering and Engineering Vibration 2023年第1期22卷 211-223页

作者： Wu Kun li ning li Zhongxian School of Transportation Science and Engineering Civil Aviation University of ChinaTianjin 300300China Key Laboratory of Coast Civil Structures Safety of the Ministry of Education Tianjin UniversityTianjin 300350China

The effects of ground motion spatial variability(GMSV)or fluid-structure interaction(FSI)on the seismic responses of deep-water bridges have been extensively ***,there are few studies on the seismic performance of bridges considering GMSV and FSI effects *** this study,the original multiple-support response spectrum(MSRS)method is extended to consider FSI effect for seismic analysis of deep-water *** solution of hydrodynamic pressure on a pier is obtained using the radiation wave theory,and the FSI-MSRS formulation is derived according to the random vibration *** influence of FSI effect on the related coefficients is analyzed.A five-span steel-concrete continuous beam bridge is adopted to conduct the numerical *** load conditions are designed to investigate the variation of the bridge responses when considering the GMSV and FSI *** results indicate that the incoherence effect and wave passage effect decrease the bridge responses with a maximum percentage of 86%,while the FSI effect increases the responses with a maximum percentage of 26%.The GMSV and FSI effects should be included in the seismic design of deep-water bridges.

关键词： response spectrum method seismic response of bridge ground motion spatial variability fluid-structure interaction rdiation wave theory

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Manufacture the conducting polymer with light

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Science China Chemistry 2025年第01期 8-9页

作者： Yang li Tianyu li Yan Ji Baoguang liu College of Electronic and Optical Engineering & College of Flexible Electronics (Future Technology) Nanjing University of Posts & Telecommunications

Poly(3,4-ethylenedioxythiophene) (PEDOT), heralded as the “king” of conducting polymers, is esteemed in bioelectronics for its mixed electronic and ionic conductivity, mechanical properties compatible with biological tissues, tunable healing ability and stability in diverse environments [1]. Based on additive manufacturing of three-dimensional structures,PEDOT realizes the implementation in the efficient production of flexible bioelectronics, the construction of intricate electrode-neural implantations, and the development of smart brain-computer-interfaces [2].

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Vector-intensity measure based seismic vulnerability analysis of bridge structures

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Earthquake Engineering and Engineering Vibration 2014年第4期13卷 695-705页

作者： li Zhongxian li Yang li ning School of Civil Engineering Tianjin University Key Laboratory of Coast Civil Structure Safety Ministry of Education

This paper presents a method for seismic vulnerability analysis of bridge structures based on vector-valued intensity measure （viM）, which predicts the limit-state capacities efficiently with multi-intensity measures of seismic event. Accounting for the uncertainties of the bridge model, ten single-bent overpass bridge structures are taken as samples statistically using Latin hypercube sampling approach. 200 earthquake records are chosen randomly for the uncertainties of ground motions according to the site condition of the bridges. The uncertainties of structural capacity and seismic demand are evaluated with the ratios of demand to capacity in different damage state. By comparing the relative importance of different intensity measures, Sa（T1） and Sa（T2） are chosen as viM. Then, the vector-valued fragility functions of different bridge components are developed. Finally, the system-level vulnerability of the bridge based on viM is studied with Duunett- Sobel class correlation matrix which can consider the correlation effects of different bridge components. The study indicates that an increment IMs from a scalar IM to viM results in a significant reduction in the dispersion of fragility functions and in the uncertainties in evaluating earthquake risk. The feasibility and validity of the proposed vulnerability analysis method is validated and the bridge is more vulnerable than any components.

关键词： bridge structure seismic vulnerability analysis vector-valued intensity measure components' correlation system vulnerability

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