检索结果-南通市图书馆

Asynchronous recruitment history of Abies spectabilis along an altitudinal gradient in the Mt. Everest region

Journal of Plant Ecology 2012年第2期5卷 147-156页

作者： Li-Xin Lv qi-bin zhang State Key Laboratory of Vegetation and Environmental Change Institute of BotanyChinese Academy of SciencesBeijing 100093China Graduate University of Chinese Academy of Sciences Beijing 100049China

Aims Forest growth and recruitment and their relationships to climate are *** aims of our study are(i)to examine the patterns in tree radial growth and recruitment along an altitudinal gradient in *** region and(ii)to identify the climatic factors that are responsible to the observed patterns in tree growth and *** Four plots,each 30360 m in size,were established from the lower to upper limits of the eastern Himalayan fir forest in Dingjie County of the *** Nature Reserve,*** techniques were applied to obtain information about the radial growth and age of the trees in the *** analysis was used to identify the relationships between radial growth and recruitment of trees and climatic variables,*** mean temperature and Palmer Drought Severity Index(PDSI).The population age structure was analyzed to investigate the recruitment *** Findings The timberline plot was characterized by significant tree recruitments in the recent three decades and sporadic recruitments in earlier *** other three plots showed recruitment pulses during 1880–1910 in Plot 3700 m,during 1870–80 and 1920–30 in Plot 3520 m and during 1900–40 in Plot 3410 *** recruitment of fir trees in the timberline was sensitive to summer(June–September)temperatures,but it was mainly controlled by episodic disturbances in lower *** radial growth in the upper two plots was positively correlated with previous winter and current August *** radial growth at the two lower plots was positively correlated with PDSI from previous September to current September.

关键词： tree rings tree recruitment age structure disturbance timberline dynamics

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

Growth Rings of Roots in Perennial Forbs in Duolun Grassland, Inner Mongolia, China

引用

Journal of Integrative Plant Biology 2007年第2期49卷 144-149页

作者： Yong-Bo Liu qi-bin zhang Laboratory of Quantitative Vegetation Ecology Institute of Botany the Chinese Academy of Sciences Beijing 100093 China Graduate University of the Chinese Academy of Sciences Beijing 100049 China

Annual growth rings of roots in perennial forbs have been used in studies of climate change and the ecology of grasslands. However, little has been done in this aspect of research in China. In this study, we report the characteristics of growth rings in the main roots of 13 herb species sampled in Duolun of the Inner Mongolia grassland in northern China. The results show that around two thirds of the species possess clearly demarcated annual rings in the root xylem. Some species of the same genera show different patterns in anatomical structure of the root xylem. Standardized annual ring widths of three species, Potentilla anserine L., Cymbaria dahurica L. and Lespedeza daurica （Laxm.） Schindh, show a common linear trend, indicating a continued favorable growth condition in the sampling sites. Our results provide evidence that growth rings in roots of some perennial forbs in the Inner Mongolia grassland can serve as a new and useful indicator of past changes in the grassland environment.

关键词： China growth ring herb-chronology perennial forbs.

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

Changes of growth-climate relationships of Smith fir forests along an altitudinal gradient

引用

Journal of Forestry Research 2024年第5期35卷 37-46页

作者： Jiacheng Zheng Jing Yang Hengfeng Jia Lixin Lyu Jiayang Langzhen qi-bin zhang State Key Laboratory of Vegetation and Environmental Change Institute of BotanyChinese Academy of SciencesBeijing 100093People’s Republic of China University of Chinese Academy of Sciences Beijing 100049People’s Republic of China Linzhou Bureau of Meteorology LinzhouLhasa 851611TibetPeople’s Republic of China Institute of Plateau Ecology Tibet Agricultural and Animal Husbandry UniversityLinzhi 860000TibetPeople’s Republic of China

Temporal changes in the relationship between tree growth and climate have been observed in numerous forests across the *** patterns and the possible regu-lators(e.g.,forest community structure)of such changes are,however,not well understood.A vegetation survey and analyses of growth-climate relationships for Abies georgei ***(Smith fir)forests were carried along an altitudi-nal gradient from 3600 to 4200 m on Meili Snow Mountain,southeastern Tibetan *** results showed that the associations between growth and temperature have declined since the 1970s over the whole transect,while response to standardized precipitation-evapotranspiration indices(SPEI)strengthened in the mid-and *** between growth and vegetation data showed that tree growth was more sensitive to drought in stands with higher species richness and greater shrub *** stress on growth may be increased by heavy competition from shrub and herb *** results show the non-stationary nature of tree growth-climate associations and the linkage to for-est community *** components should be considered in future modeling and forecasting of forest dynamics in relation to climate changes.

关键词： Climate change Tree rings Altitudinal gradient Community structure Plant diversity

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

Surgical guidance system and computer navigation for simultaneous femoral osteotomy and *** arthroplasty for treatment of osteoarthritis associated with severe extra-articular deformity

引用

Chinese Medical Journal 2012年第22期125卷 4145-4148页

作者： SHAO Jun-jie WANG qi YUAN Jian-bin zhang Xian-long Shanghai Jiao Tong Univ Dept Joint Surg Shanghai Peoples Hosp 6 Shanghai 200233 Peoples R China Shanghai Jiao Tong Univ Shanghai 200233 Peoples R China

Total knee arthroplasty （TKA） is an effective treatment for severe knee arthritis. However, TKA is more challenging when that arthritis is associated with femoral deformity that has resulted in irregularity of the canal and variation in anatomic landmarks. In such cases, it is difficult to restore the mechanical alignment of the lower limb using intramedullary instruments.

关键词： arthroplasty computer assisted surgery deformity guidance knee replacement

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

Metal nanoparticles decorated CoFe-(oxy)hydroxysulfides nanosheets fabricated by a general strategy for electrocatalytic water splitting

引用

Journal of Energy Chemistry 2025年第1期100卷 26-38页

作者： Xiaodong Yang Haochen Shen Xiaoming Xiao Zhichao Li qi Zhou Wei Yang bin Jiang Yongli Sun Luhong zhang Zhenhua Yan School of Chemical Engineering and Technology Tianjin University Key Laboratory of Advanced Energy Materials Chemistry (Ministry of Education) Nankai University

This study presents a novel method to fabricate metal-decorated,sulfur-doped layered double hydroxides （M/SLDH） through spontaneous redox and sulfurization *** developed Ag/SLDH and Pt/SLDH catalysts with abundant heterogeneous interfaces and hierarchical nanostructures demonstrated outstanding oxygen evolution reaction （OER） and hydrogen evolution reaction （HER） performance,achieving low overpotentials of 212 and 35 mV at 10 mA cm-2in 1 M KOH,*** both anode and cathode in water splitting,they required only 1.47 V to reach 10 mA cm-2and exhibited high structural robustness,maintaining stability at 1000 mA cm-2for 300 ***-situ Raman analysis revealed that the synergistic effects of metal nanoparticles and S doping significantly promote the transformation into the S-Co1-xFexOOH layer,which serves as the active phase for water ***,ultraviolet photoelectron spectroscopy （UPS） and density functional theory （DFT） analyses indicated that incorporating metal nanoparticles and S doping increase electron density near the Fermi level and reduce reaction energy barriers,thus enhancing intrinsic OER and HER *** study provides a scalable strategy for synthesizing high-performance electrocatalysts for water splitting,with promising potential for broader applications.

关键词： Ultraviolet photoelectron spectroscopy

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

Geology and mineralization of the Dayin’gezhuang supergiant gold deposit(180 t)in the Jiaodong Peninsula,China:A review

引用

China Geology 2022年第4期5卷 696-721页

作者： Xiang-dong Liu Zheng-jiang Ding Ming-chun Song Ming-ling Zhou Shao-hui Xu Zhen-liangYang Tian-ci Xie Tao Cui Ying-xin Song Xue-kan Gao Rui-xiang Li Liang-liang zhang qi-bin zhang Shan-shan Wang bin Wang No.6 Geological Team of Shandong Provincial Bureau of Geology and Mineral Resources Weihai 264209China Ministry of Natural Resources Technology Innovation Center for Deep Gold Resources Exploration and Mining Weihai 264209China State Key Laboratory of Geological Process and Mineral Resources China University of Geosciences(Beijing)Beijing 100083China Hebei Key Laboratory of Strategic Critical Mineral Resources Hebei GEO UniversityShijiazhuang 050031China Shandong Institute of Geological Sciences Jinan 250013China Dayin’gezhuang Gold Company Zhaojin Mining Co.Ltd.Zhaoyuan 264000China

The Dayin’gezhuang gold deposit is located in the central part of the Zhaoping Fault metallogenic belt in the Jiaodong gold province-the world’s third-largest gold metallogenic *** is a typical successful case of prospecting at a depth of 500-2000 m in recent years,with cumulative proven gold resources exceeding 180 *** main orebodies(No.1 and No.2 orebody)generally have a pitch direction of NNE and a plunge direction of *** the ore-controlling fault,the Zhaoping Fault is a shovel-shaped stepped fault,with its dip angle presenting stepped high-to-low transitions at the elevation of -2000-0 *** gold mineralization enrichment area is mainly distributed in the step parts where the fault plane changes from steeply to gently,forming a stepped metallogenic pattern from shallow to *** can be concluded from previous studies that the gold mineralization of the Dayin’gezhuang gold deposit occurred at about 120 *** ore-forming fluids were H_(2)O-CO_(2)-NaCl-type hydrothermal solutions with a medium-low temperature and medium-low *** H-O isotopic characteristics indicate that the fluids in the early ore-forming stage were possibly magmatic water or mantle water and that meteoric water gradually entered the ore-forming fluids in the late ore-forming *** S and Pb isotopes indicate that the ore-forming materials mainly originate from the lower crust and contain a small quantity of mantle-derived *** comprehensive analysis shows that the Dayin’gezhuang gold deposit was formed by thermal uplifting-extensional *** strong crust-mantle interactions,large-scale magmatism,and the material exchange arising from the transformation from adakitic granites to arc granites and from the ancient lower crust to the juvenile lower crust during the Early Cretaceous provided abundant fluids and material sources for ***,the detachment faults formed by the rapid magmatic uplift and the extensional tectonism created favorable tem

关键词： Stepped metallogenic model Thermal uplifting-extension mineralization Geological characteristics Supergiant gold deposit Zhaoping metallogenic belt Jiaodong gold province Mineral exploration engineering Dayin’gezhuang Shandong Province China

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

Ammonia pyrolysis oxidation excited by nanosecond pulsed discharge:Global/fluid models hybrid solution

引用

Journal of Energy Chemistry 2025年第1期100卷 385-396页

作者： Mingming zhang Hanyu Wu qi Chen Jiaxin Yang Bonan Liu School of Mechanical Electronic and Control Engineering Beijing Jiaotong University China University of Petroleum

The kinetic characteristics of plasma-assisted oxidative pyrolysis of ammonia are studied by using the global/fluid models hybrid solution ***,the stable products of plasma-assisted oxidative pyrolysis of ammonia are *** results show that the consumption of NH3/O2and the production of N2/H2change linearly with the increase of voltage,which indicates the decoupling of nonequilibrium molecular excitation and oxidative pyrolysis of ammonia at low ***,the detailed reaction kinetics mechanism of ammonia oxidative pyrolysis stimulated by a nanosecond pulse voltage at low pressure and room temperature is *** on the reaction path analysis,the simplified mechanism is *** detailed and simplified mechanism simulation results are compared with experimental data to verify the accuracy of the simplified ***,based on the simplified mechanism,the fluid model of ammonia oxidative pyrolysis stimulated by the nanosecond pulse plasma is established to study the pre-sheath/sheath behavior and the resultant consumption and formation of key *** results show that the generation,development,and propagation of the pre-sheath have a great influence on the formation and consumption of *** consumption of NH3by the cathode pre-sheath is greater than that by the anode pre-sheath,but the opposite is true for OH and O（1S）.However,within the sheath,almost all reactions do not ***,by changing the parameters of nanosecond pulse power supply voltage,it is found that the electron number density,electron current density,and applied peak voltages are not the direct reasons for the structural changes of the sheath and ***,the discharge interval has little effect on the sheath structure and gas mixture *** research results of this paper not only help to understand the kinetic promotion of non-equilibrium excitation in the process of oxidative pyrolysis but also help to explore th

关键词： Nanosecond pulsed discharge Ammonia Oxidative pyrolysis Fluid model Global model

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

Visible-light-responsive homologous heterostructure of oxynitrides constructed to boost charge separation and water splitting

引用

Science China Chemistry 2025年第1期68卷 186-191页

作者： Hai Zou Yunfeng Bao Xueshang Xin Yu qi Tengfeng Xie Fuxiang zhang State Key Laboratory of Catalysis Dalian National Laboratory for Clean Energy Dalian Institute of Chemical Physics Chinese Academy of Sciences School of Chemistry and Chemical Engineering Liaoning Normal University College of Chemistry Jilin University

Constructing type II heterostructures represents a widely recognized strategy for enhancing charge separation and photocatalytic efficiency,but it remains challenging to fabricate homologous heterostructures based on visible-light-responsive semiconductors,especially for popularly investigated （oxy）nitrides with low thermal ***,we synthesized a homologous heterostructure （denoted as YTON＿H） based on the oxynitrides of YTaO4-xNyand YTa *** heterostructure exhibits type II band structure alignment and intimate interface achieved through a magnesium （Mg） powder-assisted nitridation *** with widely reported heterologous heterostructures,the as-obtained YTON＿H homologous heterostructure could similarly exhibit enhanced charge separation as well as photocatalytic water splitting performance with respect to its counterparts(YTaO4-xNyand YTaON2).Meanwhile,detailed structural characterizations and spectroscopy analysis have been made to confirm the formation of heterostructure and promotion of spatial charge separation.

关键词： charge separation heterostructure oxynitride photocatalysis visible light

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

Atmospheric reductive catalytic fractionation of lignocellulose integrated with one-pot catalytic conversion of carbohydrate yielding valuable lignin monomers and platform chemicals from corn straw

引用

Green Energy & Environment 2025年第1期10卷 161-172页

作者： Meng-Ying Liu Zhe-Hui zhang Xue-qi Wang qian Sun Chen zhang Yu Li Zhuohua Sun Katalin Barta Feng Peng Tong-qi Yuan State Key Laboratory of Efficient Production of Forest Resources Beijing Forestry UniversityBeijing100083China Beijing Key Laboratory of Lignocellulosic Chemistry Beijing Forestry UniversityBeijing100083China Department of Chemistry Organic and Bioorganic ChemistryUniversity of GrazHeinrichstrasse 28/II8010 GrazAustria

Developing a cost-effective and environmentally friendly process for the production of valuable chemicals from abundant herbal biomass receives great attentions in recent ***,taking advantage of the“lignin first”strategy,corn straw is converted to valuable chemicals including lignin monomers,furfural and 5-methoxymethylfurfural via a two steps *** key of this research lies in the development of a green and low-cost catalytic process utilizing magnetic Raney Ni catalyst and high boiling point ethylene *** utilization of neat ethylene glycol as the sole slovent under atmospheric conditions obviates the need for additional additives,thereby facilitating the entire process to be conducted in glass flasks and rendering it highly convenient for scaling *** the initial step,depolymerization of corn straw lignin resulted in a monomer yield of 18.1 wt%.Subsequently,in a dimethyl carbonate system,the carbohydrate component underwent complete conversion in a one-pot process,yielding furfural and 5-methoxymethylfurfural as the primary products with an impressive yield of 47.7%.

关键词： Atmospheric reductive catalytic fractionation Corn straw Ethylene glycol Raney Ni 5-Methoxymethylfurfural

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

Mesh-supported V2O5-WO3/TiO2 nanosheet array catalysts for efficient removal of NOx

引用

Tungsten 2025年第1期7卷 100-111页

作者： Zhi-qi zhang Liu Yang Wen Luo Vladimir An Jing Li Bao-Dan Liu School of Materials Science and Engineering Northeastern University Foshan Graduate School of Innovation Northeastern University Kizhner Research Center School of Advanced Manufacturing Technologies Tomsk Polytechnic University

The design and synthesis of vanadium-based denitration catalysts with low-temperature activity pose significant challenges in the field of toxic gas *** this study,we have developed a novel approach to fabricate highly efficient V2O5-WO3/TiO2monolithic mesh catalysts for NOxreduction at low ***,TiO2nanosheets with strong adhesion and large surface area were grown on Ti mesh using plasma electrolytic oxidation technology and hydrothermal ***,super-small traces of WO3and V2O5active nano-species were subsequently deposited on TiO2nanosheets using the deposition-precipitation *** to traditional ceramic-based V2O5-WO3/TiO2catalysts,our V2O5-WO3/TiO2monolithic mesh catalyst exhibits superior mechanical performance,excellent thermal conductivity,lower pressure drop,higher utilization of active components,and stronger synergistic ***,the V2O5-WO3/TiO2monolithic mesh catalysts exhibited excellent low-temperature catalytic activity with 98% of NOxconversion at 220℃,and remarkable long-term SO2tolerance and water resistance in the selective catalytic reduction（SCR） of NOxwith *** SCR reaction of tiny V2O5and WO3active species supported on TiO2nanosheets directly demonstrated to follow the Eley-Rideal mechanism by in situ infrared spectra.

关键词： Low temperature activity Monolithic mesh catalysts NH3-SCR SO2 tolerance V2O5-WO3/TiO2

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

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：