检索结果-南通市图书馆

linking leaf elemental traits to biomass across forest biomes in the Himalayas

Science China earth Sciences 2024年第5期67卷 1518-1528页

作者： Nita DYOlA eryuan lIANG j.sep peÑUelAS j.j.lio CAMAReRO Shalik Ram SIGDel Sugam ARYAl Wentao lIN Xiang lIU Yongwen lIU Xingliang XU Sergio ROSSI State Key laboratory of Tibetan Plateau earth System Environment and Resources(TPESER)Institute of Tibetan Plateau ResearchChinese Academy of SciencesBeijing 100101China University of Chinese Academy of Sciences Beijing 100049China laboratoire sur lesécosystèmes terrestres boréaux Département des Sciences FondamentalesUniversitédu QuébecàChicoutimi555Boulevard de l′UniversitéChicoutimi(QC)G7H2B1Canada CSIC Global Ecology Unit CREAF-CSIC-UABBellaterraE-08193 CataloniaSpain CReAF Cerdanyola del VallèsE-08193 CataloniaSpain Instituto Pirenaico de ecología(Ipe-CSIC) Avenida Montañana 1005Zaragoza 50059Spain Friedrich-Alexander-Universität erlangen-Nürnberg Institut für GeographieErlangen 91058Germany State Key laboratory of Grassland Agro-ecosystems College of EcologyLanzhou UniversityLanzhou 730000China Key laboratory of ecosystem Network Observation and Modeling Institute of Geographic Sciences and Natural Resources ResearchChinese Academy of SciencesBeijing 100101China

Plants require a number of essential elements in different proportions for ensuring their growth and *** elemental concentrations in leaves reflect the functions and adaptations of plants under specific environmental ***,less is known about how the spectrum of leaf elements associated with resource acquisition,photosynthesis and growth regulates forest biomass along broad elevational *** examined the influence of leaf element distribution and diversity on forest biomass by analyzing ten elements(C,N,P,K,Ca,Mg,Zn,Fe,Cu,and Mn)in tree communities situated every 100 meters along an extensive elevation gradient,ranging from the tropical forest(80 meters above sea level)to the alpine treeline(4200 meters above sea level)in the Kangchenj.nga landscape in eastern Nepal *** calculated communityweighted averages(reflecting dominant traits governing biomass,i.e.,mass-ratio effect)and functional divergence(reflecting increased trait variety,i.e.,complementarity effect)for leaf elements in a total of 1,859 trees representing 116 *** increasing mass-ratio effect and decreasing complementarity in leaf elements enhance forest biomass accumulation.A combination of elements together with elevation explains biomass(52.2%of the variance)better than individual elemental trait diversity(0.05%to 21%of the variance).elevation modulates trait diversity among plant species in biomass *** promotes biomass at lower elevations,but reduces biomass at higher elevations,demonstrating an interaction between elevation and *** interaction between elevation and mass-ratio effect produces heterogeneous effects on biomass along the elevation *** research indicates that biomass accumulation can be disproportionately affected by elevation due to interactions among trait diversities across vegetation *** higher trait variation enhances the adaptation of species to environmental changes,it reduces

关键词： ecosystem function elevational gradient Functional diversity Functional traits leaf elements Niche complementarity

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

Modeling slow deformation of polygonal particles using DeM

引用

Particuology 2008年第6期6卷 506-514页

作者： Andrés A. pea pedro G. lind Hans j. Herrmann Institute for Computational Physics Universitt Stuttgart Computational Physics IfB HIF E12 ETH Hnggerberg CH-8093 Zrich Switzerland Departamento de Física Universidade Federal do Ceará

We introduce two improvements in the numerical scheme to simulate collision and slow shearing of irregular particles. First, we propose an alternative approach based on simple relations to compute the frictional contact forces. The approach improves efficiency and accuracy of the Discrete element Method （DeM） when modeling the dynamics of the granular packing. We determine the proper upper limit for the integration step in the standard numerical scheme using a wide range of material parameters. To this end, we study the kinetic energy decay in a stress controlled test between two particles. Second, we show that the usual way of defining the contact plane between two polygonal particles is, in general, not unique which leads to discontinuities in the direction of the contact plane while particles move. To solve this drawback, we introduce an accurate definition for the contact plane based on the shape of the overlap area between touching particles, which evolves continuously in time.

关键词： Granular media Discrete element method Slow deformation Contact forces

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

Synthesis of coral-like structures of Pr-Yb co-doped YIG: Structural,optical, magnetic and antimicrobial properties

引用

j.urnal of Rare earths 2024年第3期42卷 543-554,I0004页

作者： A.Fernandez Francisca P.Arauj. Y.Guerra S.Castro-lopes j.Matilla-Arias Idglan S.de lima edson C.Silva-Filho j.sy A.Osaj.ma F.Guerrero R.pena-Garcia Federal University of Piau Graduate Program in Materials Science and EngineeringTeresinaPIBrazil Federal Rural University of pernambuco Academic Unit of Cabo de Santo AgostinhoCabo de Santo AgostinhoPEBrazil Federal University of Piaui Department of PhysicTeresinaPBrazil Federal University of pernambuco Graduate Program in Materials ScienceRecifePEBrazil University of Granma Departmentof Basic Sciences and Applied InformaticsFaculty of Technical SciencesBayamoCuba Federal University of Amazonas Department of PhysicManausAMBrazil Federal University of pernambuco Department of PhysicRecifePEBrazil

Coral-like structures of the Y_(3-x)Pr_(x)Fe_(5-y)Yb_(y)O_(12),(0.00 ≤ x ≤ 0.04, 0.00 ≤ y ≤ 0.02) compound were synthesized using the sol-gel method. Structural investigation certified the YIG cubic crystal structure formation, without any secondary phase. It is shown that, the relatively large ionic radius of the dopant cations results in an expansion of the lattice parameter, variations in the Iona-O-Iondangle, Iona-O,Iond-O and Ionc-O bond distances and decrease in the average crystallite size. Fourier transform infrared(FTIR) and Raman measurements are essential to testify the single-phase formation of YIG crystal structure and are observed changes in the stretching and vibrational modes, respectively. The morphological study, energy dispersive spectroscopy(eDS) spectra and textural properties show corallike structures, peaks associated with Pr^(3+) and Yb^(3+) atoms and the effect of dopants on surface area,diameter, and pore volume, respectively. The optical analysis from diffuse reflectance spectra witnessed an increase in the optical gap band, a decrease in Urbach energy and blue shift in the charge transfer,correlated with the expansion of the unit cell due to the dopant's insertion in the YIG structure. A typical ferrimagnetic behavior is exhibited by the Y_(3-x)Pr_(x)Fe_(5-y)Yb_(y)O_(12)compound. The saturation magnetization(M_(s)), cubic anisotropy constant(K_(1)) and coercive field(H_(c)) increase with the Pr^(3+)cations content, as consequence of their magnetic nature and distribution around of Fe^(3+)ions due to the coexistence with the Yb^(3+). Finally, for the first time, antibacterial tests by mean of the direct contact method were performed for YIG co-doped with Pr^(3+)and Yb^(3+)and it is shown that, relatively high dosages of Pr^(3+) cations favored the activity against S. aureus, therefore, a new biological property for YIG doped with rare earths is presented.

关键词： Yttrium iron garnet(YIG) Coral-like structures Rare earths Band gap energy Magnetic properties Antimicrobial properties

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

Global perspectives on the ecological,cultural and socioeconomic relevance of wild edible fungi

引用

Studies in Fungi 2021年第1期6卷 408-424页

作者： Pérez-Moreno j.Mortimer pe Xu j.Karunarathna SC li H Centre for Mountain Futures Kunming Institute of BotanyChinese Academy of SciencesKunmingChina edafología Campus MontecilloColegio de PostgraduadosTexcocoMéxico CIFOR-ICRAF China Program World Agroforestry(ICRAF)KunmingChina

Wild edible fungi(WeF),including mushrooms and truffles,comprise a natural source of nutritious and healthy *** consumption of WeF began at least 18,700 years ago during the Stone *** data from over 100 countries indicates the existence of more than 2,100 edible species,a figure that is continually growing,as vast regions and many cultures remain ***,only around 30 species of WeF are grown commercially at a *** also play a key ecological role in the structure and functioning of natural ecosystems and have significantly contributed in shaping all life on the *** as food,medicine or both,they are important for the survival,cultures,and economies of hundreds of ethnic groups around the *** the last 15 years,there has been a noteworthy increase in the international trade of WeF,which is currently estimated at billions(USD)*** 2017,the WeF global trade,of either fresh or processed products,exceeded 1,230,000 *** to their ecological,sociocultural and economic importance,the international WeF trade has a role to play in the post-pandemic recovery *** main challenge of this period will be maintaining natural ecosystems while simultaneously improving human *** elements of this challenge include ensuring food security,enhancing rural development,creating sustainable j.bs,mitigating hunger,and slowing the loss of traditional knowledge generated over *** review analyzes the ways in which sustainable use of WeF could contribute to achieving these goals.

关键词： Biocultural importance edible Wild Mushrooms Global Sustainable Development Socioeconomic value Traditional knowledge

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

Suitable conditions for natural regeneration in variable retention harvesting of southern Patagonian Nothofagus pumilio forests

引用

ecological Processes 2019年第1期8卷 240-251页

作者： Mónica D.R.Toro Manríquez j.an M.Cellini María V.lencinas Pablo l.peri Karen A.peña Roj.s Guillermo j.Martínez Pastur Centro Austral de Investigaciones Científicas(CADIC) Consejo Nacional de Investigaciones Científicas y Técnicas(CONICET)Houssay 200(9410)UshuaiaTierra del FuegoArgentina laboratorio de Investigaciones en Maderas(lIMAD) Universidad Nacional de la Plata(UNLP)Diagonal 113 n°469(1904)La PlataBuenos AiresArgentina Instituto Nacional de Tecnología Agropecuaria(INTA) Universidad Nacional de la Patagonia Austral(UNPA)Consejo Nacional de Investigaciones Científicas y Técnicas(CONICET)cc 332(9400)Río GallegosSanta CruzArgentina Departamento de Silvicultura y Conservación de la Naturaleza Facultad de Ciencias Forestales y de Conservación de la NaturalezaUniversidad de Chilecc 9206SantiagoChile.

Background:Variable retention(aggregated and dispersed retention)harvesting proposed for Nothofagus pumilio was designed for timber purposes and biodiversity *** by opening canopy generates different microenvironments and creates contrasting conditions for seedling establishment,growth,and eco-physiology performance due to synergies(positives or negatives)with biotic and abiotic *** study evaluated the regeneration in different microenvironment conditions within managed stands during 5 years after *** forest structure after harvesting and different microenvironments were characterized in managed stands,where 105 regeneration plots were measured(3 stands×7 microenvironments×5 replicas).We characterized the seedling bank,as well as growth and ecophysiology performance of the *** and multivariate analyses were conducted for the ***:Microenvironments offered different environmental conditions for natural regeneration(soil moisture and light availability).Seedling under debris and dicot plants showed better eco-physiological performance,establishment,and growth than plants growing under monocots or located in the dispersed retention without the protection of other understory *** most unfavorable microenvironment conditions were high canopy cover of remnant trees(inside the aggregates or close to trees in the dispersed retention)and heavily impacted areas(skidder extraction roads).Conclusions:Favorable microenvironments in the harvested areas will improve the natural recruitment,growth,and eco-physiology performance of the natural regeneration after *** is necessary to develop new silvicultural practices that decrease the unfavorable microenvironments(e.g.,road density or excessive woody accumulation),to assure the success of the proposed silvicultural method.

关键词： Aggregated retention Dispersed retention Microenvironments environmental variables Biometric values Biomass allocation eco-physiology

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

Adsorption of Pharmaceuticals and personal Care Products on Granular Activated Carbon

引用

j.urnal of Surface engineered Materials and Advanced Technology 2016年第4期6卷 183-200页

作者： Nasly Y. Delgado Alberto l. Capparelli Damián j. Marino Agustín F. Navarro Gustavo A. peñuela Alicia e. Ronco Centro de Investigaciones del Medio Ambiente Facultad de Ciencias Exactas Universidad Nacional de la Plata (UNLP) La Plata Argentina Consej. Nacional de Investigaciones Científicas y Técnicas La Plata Argentina División Fisicoquímica Facultad de Ciencias Exactas UNLP La Plata Argentina Departamento de Ingeniería Química Facultad de Ingeniería UNLP La Plata Argentina Grupo GDCON Universidad de Antioquia Medellín Colombia

We investigated the adsorption to granular activated carbon of two pharmaceuticals (carbamazepine and sildenafil citrate) and a personal-care product (methylparaben) in aqueous solution, characterized the carbon, and evaluated its influence on the kinetics and adsorption equilibrium of the compounds under study. We adj.sted data for the analysis of equilibrium to langmuir and Freundlich models of adsorption isotherms and described adsorption rate using pseudo first- and second-order models;that same analysis was made on the basis of the behavior of the initial rate. In addition, we analyzed the potentiality of a nonlinear adj.stment for studying kinetics and equilibrium of adsorption, an approach requiring neither knowledge of equilibrium conditions nor a-priori hypothetical suppositions regarding the order of reaction. The results indicated that the nonlinear model was capable of describing adsorption kinetic behavior, in order to determine concentrations adsorbed at equilibrium, adsorption rates of the system, maximum adsorption capacity, and global rate constant. Granular carbon exhibited an adsorption capacity for carbamazepine and methylparaben of ca. 323 mg/g and for sildenafil citrate of ca. 142 mg/g, though with slow adsorption kinetics characterized by average adsorption times of at least 168 h.

关键词： Activated Carbon Carbamazepine Sildenafil Citrate Methylparaben Adsorption

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

软质小麦品质性状与酥性饼干品质参数的关系研究

引用

作物学报 2005年第9期31卷 1125-1131页

作者：张岐军张艳何中虎 R j.pea 中国农业科学院作物科学研究所/国家小麦改良中心国际玉米小麦改良中心

选用我国17份软质小麦品种（系）在3点种植2年，研究软质小麦品质性状与酥性饼干品质的关系，探讨优质饼干品种的筛选指标。结果表明，粉质仪和拉伸仪参数与饼干品质的相关系数较小；吹泡仪弹性、吹泡仪弹性，延伸性、碱水保持力（AWRC... 详细信息

选用我国17份软质小麦品种（系）在3点种植2年，研究软质小麦品质性状与酥性饼干品质的关系，探讨优质饼干品种的筛选指标。结果表明，粉质仪和拉伸仪参数与饼干品质的相关系数较小；吹泡仪弹性、吹泡仪弹性，延伸性、碱水保持力（AWRC）、碳酸钠溶剂保持力（SRC）和蔗糖SRC与饼干直径关系密切，相关系数分别为-0．79、-0．75、-0．78、-0．79和-0．80，可作为饼干品质的筛选指标。筛选出建麦1号、皖麦19和皖麦48三个饼干品质优良的品种，提出了优质饼干小麦品种的具体品质指标，即籽粒硬度（SKCS）1～40，籽粒蛋白质含量9．0％～11．5％，面粉蛋白质含量8．0％～10．0％，吹泡仪弹性≤40mm，弹性，延伸性≤0．50，吹泡仪能量≤75×10^-4j.碱水保持力≤59％，水SRC≤53％，碳酸钠SRC≤66％，乳酸SRC≤83％，蔗糖SRC≤87％，饼干直径≥480mm。

关键词：普通小麦酥性饼干溶剂保持力(SRC) 面团流变学特性

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

Mercury removal using ground and calcined mussel shell

引用

j.urnal of environmental Sciences 2013年第12期25卷 2476-2486页

作者： Susana pea-Rodríguez Alipio Bermúdez-Couso j.an Carlos Nóvoa-Muoz Manuel Arias-estvez María j.Fernndez-Sanj.rj. esperanza lvarez-Rodríguez Avelino Núez-Delgado rea de edafoloxía e Qu' mica Agr' cola. Departamento de Bioloxía Vexetal e Ciencia do Solo. Univ. Vigo. Facultade de Ciencias Ourense Departamento de edafoloxía e Química Agrícola. Univ. Santiago de Compostela. escola Politcnica Superior campus univ. s/n

We determined mercury retention on calcined and ground mussel shell, in presence and absence of phosphate, using batch and stirred flow chamber experiments. In batch experiments the calcined shell exhibited higher Hg adsorption, with good fitting to Freundlich equation （R^2： 0.925-0.978）; the presence of phosphate increased Hg adsorption; mercury desorption was 13% or lower, diminishing up to 2% under the presence of phosphates. In stirred flow chamber experiments calcined shell retained more Hg than ground shells （6300 vs. 4000-5200 μmol/kg）; Hg retention increased an additional 40% on calcined shell and up to an additional 70% on ground shells when phosphates were present; mercury desorption was quite similar in all shell types （20%-34%）, increasing up to 49%-60% in ground shells when phosphates were present. The higher Hg adsorption on calcined shell would be related to its calcite and dolomite concentrations; mercury-phosphate interactions would cause the increase in Hg retention when phosphates are present. Data on Hg desorption suggest that Hg retention was not easily reversible after batch experiments, increasing in the stirred flow chamber due to convective flow. Calcined and ground mussel shells could be recycled removing Hg from water, with the presence of phosphates in solution improving efficacy.

关键词： adsorption desorption heavy metals pollution mercury mollusc shell

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

基于脂质组学研究胡椒碱对肥胖大鼠脂代谢基因昼夜节律的影响

引用

食品科学 2024年第9期45卷 124-134页

作者：张玮芸 HO Chi-Tang 吕慕雯华南农业大学食品学院广东广州510642 罗格斯大学食品科学系美国新布朗斯维克08901

采用高脂饮食(high fat diet,HFD)诱导的肥胖大鼠模型,探究口服胡椒碱(1-piperoylpiperidine,PIP)对代谢紊乱引发生物钟异常的调控作用。结果表明,PIP减轻了HFD诱导的肝脏损伤,降低了血脂水平,缓解了肝脏生物钟和脂代谢基因的昼夜节律紊... 详细信息

采用高脂饮食(high fat diet,HFD)诱导的肥胖大鼠模型,探究口服胡椒碱(1-piperoylpiperidine,PIP)对代谢紊乱引发生物钟异常的调控作用。结果表明,PIP减轻了HFD诱导的肝脏损伤,降低了血脂水平,缓解了肝脏生物钟和脂代谢基因的昼夜节律紊乱,恢复了与生物钟密切相关的脂质分子溶血磷脂酸(16:0_18:1)、双甲基磷脂酸(38:8e)、磷脂酰乙醇胺(16:0p_22:6)和甲基磷胆碱(32:4e)的表达水平变化。本研究结果可为PIP调节肝脏脂代谢昼夜节律提供一定的理论依据。

关键词：胡椒碱肥胖大鼠脂质代谢昼夜节律

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

effects of cellulase and xylanase enzymes mixed with increasing doses of Salix babylonica extract on in vitro rumen gas production kinetics of a mixture of corn silage with concentrate

引用

j.urnal of Integrative Agriculture 2015年第1期14卷 131-139页

作者： Abdelfattah Z M Salem German Buendía-Rodríguez Mona M M elghandour María A Mariezcurrena Berasain Francisco j.pea j.ménez Alberto B Pliego j.an C V Chagoyán María A Cerrillo Miguel A Rodríguez Faculty of Veterinary Medicine and Animal Science Autonomous University of the State of Mexico National Center of Disciplinary Research in Animal Physiology and Improvement INIFAP Ajuchitlán Institute of Agricultural Sciences Autonomous University of HidalgoEx-Hda. of Aquetzalpa Faculty of Veterinary Medicine and Animal Science Juárez University of the Durango State

An in vitro gas production （GP） technique was used to investigate the effects of combining different doses of Salix babylonica extract （SB） with exogenous fibrolytic enzymes （eZ） based on xylanase （X） and cellulase （C）, or their mixture （XC; 1：1 v/v） on in vitro fermentation characteristics of a total mixed ration of corn silage and concentrate mixture （50：50, w/w） as substrate. Four levels of SB （0, 0.6, 1.2 and 1.8 ml g-1 dry matter （DM）） and four supplemental styles of eZ （1 μl g-1 DM; control （no enzymes）, X, C and XC （1：1, v/v） were used in a 4×4 factorial arrangement. In vitro GP （ml g-1 DM） were recorded at 2, 4, 6, 8, 10, 12, 24, 36, 48 and 72 h of incubation. After 72 h, the incubation process was stopped and supernatant pH was determined, and then filtered to determine dry matter degradability （DMD）. Fermentation parameters, such as the 24 h gas yield （GY24）, in vitro organic matter digestibility （OMD）, metabolizable energy （Me）, short chain fatty acid concentrations （SCFA）, and microbial crude protein production （MCP） were also estimated. Results indicated that there was a SBxeZ interaction （P〈0.0001） for the asymptotic gas production （b）, the rate of gas production （c）, GP from 6 to 72 h, GP2 （P=0.0095）, and GP4 （P=0.02）. The SB and different combination of enzymes supplementation influenced （P〈0.001） in vitro GP parameters after 12 h of incubation; the highest doses of SB （i.e., 1.8 ml g-1 DM）, in the absence of any eZ, quadratically increased （P〈0.05） the initial delay before GP begins （l） and GP at different incubation times, with lowering b （quadratic effect, P〈0.0001 ） and c （quadratic effect, P〈0.0001 ; linear effect, P=0.0018）. The GP was the lowest （P〈0.05） when the highest SB level was combined with cellulose. There were SBxeZ interactions （P〈0.001） for OMD, Me, the partitioning factor at 72 h of incubation （PF72）, GY24, SCFA, MCP （P=0.0143）, and pH （P=0.0008）. The OMD, Me, GY24 and SCFA with supplementation of SB extract at 1.8 ml g-1 DM were h

关键词： cellulase degradability gas production Salix babylonica xylanase

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

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：