检索结果-南通市图书馆

Soil Salinity Changes in the Jordan Valley Potentially threaten Sustainable Irrigated Agriculture

Pedosphere 2013年第3期23卷 376-384页

作者： t.g.ammari R.tAHHAN S.ABUBAKE Y.AL-ZU'BI A.tAHBOUB R.tA'ANY S.ABU-ROMMAN N.AL-MANASEER M.H.StIEtIYA Department of Water Resources and Environmental Management Faculty of Agricultural Technology Al-Balqa' Applied University Department of Natural Resources and Environment Faculty of Agriculture Jordan University of Science and Technology Department of Plant Production and Protection Faculty of Agricultural Technology Al-Balqa' Applied University Department of Biotechnology Faculty of Agricultural Technology Al-Balqa' Applied University Department of Land Water and Environment Faculty of Agriculture University of Jordan

the integrated effect of irrigation and agricultural practices on soil salinity in the Jordan Valley （JV）, where over 60% of Jordan＇s agricultural produce is grown, was investigated in this study during 2009-2010. Due to the differences in agricultural operations, cropping patterns, irrigation management, and weather conditions, 206 top- and sub-soil samples were taken every 1 to 3 km from representative farms along a north-south （N-S） transect with 1 to 2 km lateral extents. Soil electrical conductivity of saturated extract （ECse）, Ca, Mg, K, Na, CI, and Na adsorption ratio （SAR） were determined in saturated paste extracts. Results indicated that about 63% of soils in the JV are indeed saline, out of which almost 46% are moderately to strongly saline. Along the N-S transect of the JV, ECse increased from 4.5 to 14.1 dS m-1 in top-soil samples. Similar increase was observed for the sub-soil samples. the major chemical components of soil salinity; i.e., Ca, Mg, and C1, also showed a similar increase along the N-S transect of the valley. Moreover, compared to previous field sampling, results showed that changes in soil salinity in the JV were dramatic. In addition, it was found that C1 imposed an existing and potential threat to sensitive crops in 60% of the soils in the JV, where C1 concentrations were greater than 710 mg L-1. Under the prevalent arid Mediterranean conditions, improving the management of .irrigation water, crops, and nutrient inputs and increasing water and fertilizer use efficiencies should be indispensable to conserve and sustain the already fragile agricultural soils in the JV.

关键词： agricultural practices chloride electrical conductivity irrigation water quality soil salinization

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

COUPLINg OF FINItE ELEMENt AND BOUNDARY ELEMENt MEtHODS FOR tHE SCAttERINg BY PERIODIC CHIRAL StRUCtURES

引用

Journal of Computational Mathematics 2008年第3期26卷 261-283页

作者： Habib ammari gang Bao Centre de Mathématiques Appliquées CNRS UMR 7641 Ecole Polytechnique 91128 Palaiseau France Department of Mathematics Michigan State University East Lansing MI 48824 USA

Consider a time-harmonic electromagnetic plane wave incident on a biperiodic structure in R^3. the periodic structure separates two homogeneous regions. the medium inside the structure is chiral and nonhomogeneous. In this paper, variational formulations coupling finite element methods in the chiral medium with a method of integral equations on the periodic interfaces are studied. the well-posedness of the continuous and discretized problems is established. Uniform convergence for the coupling variational approximations of the model problem is obtained.

关键词： Chiral media Periodic structures Finite element method Boundary element method Convergence

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

A BOUNDARY INtEgRAL MEtHOD FOR COMPUtINg ELAStIC MOMENt tENSORS FOR ELLIPSES AND ELLIPSOIDS

引用

Journal of Computational Mathematics 2007年第1期25卷 2-12页

作者： Habib ammari HyeonbaeKang HyundaeLee Centre de Mathématiques Appliquées CNRS UMR 7641 and Ecole Polytechnique91128 Palaiseau CedexFrance Department of Mathematical Sciences and RIM Seoul National UniversitySeoul 151-747Korea

the concept of elastic moment tensor occurs in several interesting contexts, in particular in imaging small elastic inclusions and in asymptotic models of dilute elastic composites. In this paper, we compute the elastic moment tensors for ellipses and ellipsoids by using a systematic method based on layer potentials. Our computations reveal an underlying elegant relation between the elastic moment tensors and the single layer potential.

关键词： Elastic moment tensor Explicit formulae Integral equations.

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

SENSItIVItY ANALYSIS WItH RESPECt tO tHE ELECtRICAL CONDUCtIVItY

引用

Journal of Computational Mathematics 2007年第3期25卷 244-251页

作者： Habib ammari Cedex France Hyeonbae Kang Centre de Mathématiques Appliquées CNRS UMR 7641 and Ecole Polytechnique91128 Palaiseau School of Mathematical Sciences Seoul National UniversitySeoul 151-747Korea Habib Zribi Centre de Mathématiques AppliquéesCNRS UMR 7641 and Ecole Polytechnique91128 Palaiseau CedexFrance

In this paper, we consider conductivity inclusions inside a homogeneous background conductor. We provide a complete asymptotic expansion of the solution of such problems in terms of small variations in the electrical conductivity of the inclusion. Our method is based on a boundary integral perturbation theory. Our results are valid for both high and low contrast inclusions.

关键词： High contrast material Full-asymptotic expansions Boundary integral equa-tion.

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

An SPH Framework for Earthquake-Induced Liquefaction Hazard Assessment of geotechnical Structures

引用

Computer Modeling in Engineering & Sciences 2025年第1期142卷 251-277页

作者： Sourabh Mhaski g.V.Ramana Department of Civil Engineering Indian Institute of Technology DelhiNew Delhi110016India

Earthquake-induced soil liquefaction poses significant risks to the stability of geotechnical structures *** understanding of the liquefaction triggering,and the post-failure large deformation behaviour is essential for designing resilient *** present study develops a Smoothed Particle Hydrodynamics(SPH)framework for earthquake-induced liquefaction hazard assessment of geotechnical *** coupled flowdeformation behaviour of soils subjected to cyclic loading is described using the PM4Sand model implemented in a three-phase,single-layer SPH framework.A staggered discretisation scheme based on the stress particle SPH approach is adopted to minimise numerical inaccuracies caused by zero-energy modes and tensile ***,non-reflecting boundary conditions for seismic analysis of semi-infinite soil domains using the SPH method are *** numerical framework is employed for the analysis of cyclic direct simple shear test,seismic analysis of a level ground site,and liquefaction-induced failure of the Lower San Fernando *** agreement for liquefaction triggering and post-failure behaviour demonstrates that the SPH framework can be utilised to assess the effect of seismic loading on field-scale geotechnical *** present study also serves as the basis for future advancements of the SPH method for applications related to earthquake geotechnical engineering.

关键词： Earthquake seismic liquefaction stress particle PM4Sand smoothed particle hydrodynamics(SPH)

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

Adsorptive separation of La(Ⅲ)from aqueous solution via the synthesized[Zn(bim)_(2)(bdc)]_(n) metal-organic framework

引用

Journal of Rare Earths 2021年第6期39卷 742-748,I0005页

作者： Sareh ammari Allahyari Reza Saberi Kamran Sepanloo Ahmad Lashkari Nuclear Fuel Cycle School Nuclear Science and Technology Research InstituteTehranIran Reactor and Nuclear Safety Research School Nuclear Science and Technology Research InstitutePO Box 11365-8486TehranIran

Lanthanum is one of the rare earth metals which due to specific chemio-physical properties,has wide applications in different *** this research,the ability of the synthesized metal-organic framework(MOF),[Zn(bim)_(2)(bdc)]_(n)(ZBB) for the removal of lanthanum ions from the aqueous stream was investigated in the batch and column *** synthesized MOF was characterized by using scanning electron microscopy(SEM),Brunauer-Emmett-teller(BEt),Fourier transform infrared spectroscopy(FtIR) and thermogravimetric analysis(tgA).the effect of pH on lanthanum ions adsorption was evaluated in the range from 1 to ***,isothermal,kinetic,and thermodynamic parameters for adsorption of La(Ⅲ) ions onto the synthesized MOF were *** adsorption capacity of lanthanum ions onto the synthesized MOF was calculated to be about 130 mg/*** studies demonstrate the endothermic and chemical nature of lanthanum adsorption,while kinetic studies suggest the pseudo-first-order of *** column mode,the effect of solution flow rate passing through the fixed-bed was *** data confirm that increasing the bed flow rate causes a decrease in the adsorption capacity of lanthanum ions on the synthesized MOF.

关键词： La(Ⅲ)removal [Zn(bim)2(bdc)]n Kinetic study Shrinking core model(SCM) Fixed-bed column Rare earths

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

SEPARAtION OF SCALES IN ELAStICItY IMAgINg:A NUMERICAL StUDY

引用

Journal of Computational Mathematics 2010年第3期28卷 354-370页

作者： Habib ammari Pierre garapon Franois Jouve Institut Langevin Laboratoire Ondes et Acoustique Laboratoire J.L.Lions Universite Paris Ⅶ Laboratoire J.L.Lions Université Paris Ⅶ

In magnetic resonance elastography, one seeks to reconstruct the shear modulus from measurements of the displacement field in the whole body. In this paper, we present an optimization approach which solves the problem by simply minimizing a discrepancy functional. In order to recover a complex anomaly in a homogenous medium, we first observe that the information contained in the wavefield should be decomposed into two parts, a ＂near-field＂ part in the region around the anomaly and a ＂far-field＂ part in the region away from the anomaly. As will be justified both theoretically and numerically, separating these scales provides a local and precise reconstruction.

关键词： Elastography multi-scale imaging anomaly reconstruction.

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

Stepping up after spinal cord injury:negotiating an obstacle during walking

引用

Neural Regeneration Research 2025年第7期20卷 1919-1929页

作者： Alain Frigon Charly g.Lecomte Department of Pharmacology-Physiology Faculty of Medicine and Health SciencesUniversitéde SherbrookeCentre de recherche du Centre Hospitalier Universitaire de SherbrookeSherbrookeQCCanada

Every day walking consists of frequent voluntary modifications in the gait pattern to negotiate *** spinal cord injury,stepping over an obstacle becomes *** over an obstacle requires sensorimotor transformations in several structures of the brain,including the parietal cortex,premotor cortex,and motor *** information and planning are transformed into motor commands,which are sent from the motor cortex to spinal neuronal circuits to alter limb trajectory,coordinate the limbs,and maintain *** spinal cord injury,bidirectional communication between the brain and spinal cord is disrupted and animals,including humans,fail to voluntarily modify limb trajectory to step over an ***,in this review,we discuss the neuromechanical control of stepping over an obstacle,why it fails after spinal cord injury,and how it recovers to a certain extent.

关键词： biomechanics locomotion neurophysiology obstacle negotiation spinal cord injury

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

Impact of Intensive greenhouse Production System on Soil Quality

引用

Pedosphere 2015年第2期25卷 282-293页

作者： tarek g.ammari Ragheb tAHHAN Nizar AL SULEBI Alaedeen tAHBOUB Rakad A.tA'ANY Samih ABUBAKER Departemnet of Water Resources and Environmental Management Faculty of Agricultural TechnologyAl-Balqa' Applied University Departement of Natural Resources and Environment Faculty of AgricultureJordan University of Science and Technology Department of Plant Production and Protection Faculty of Agricultural TechnologyAl-Balqa' Applied University

Composite top- and subsoil samples were collected from the greenhouses in the Al-Balawneh area,Jordan,where intensive greenhouse production system(IgPS) has been practiced since 1998,to study the impact of IgPS on soil quality as measured by the chemical and biological properties to develop a sustainable production *** study showed that IgPS led to higher electrical conductivity in top- and subsoils compared to an uncultivated soil(control).Quality and amount of irrigation water,lack of efficient drainage,and quantity and types of applied fertilizers were major factors resulting in salt *** resulted in lower total N(tN) and NO_3-N in the soil compared to the *** lower tN was due to crop uptake,microbial immobilization,volatilization,and irregular application of composted animal manure or poultry *** contrast,higher residual Olsen-P content was detected in both soil layers of greenhouses than in the *** P was classified as very high in the topsoil layers and sufficient to high in the subsoil *** available K in the soils of greenhouses was relatively lower than that in the control and it was,however,classified as high to very high.A large increase of Cl and a considerable decrease in the bacterial count were observed in both soil layers of IgPS compared to the control *** sustainable soil management practices need to be adopted by farmers to achieve a sustainable and profitable *** can be accomplished through education,targeted towards the farming community in the central Jordan Valley.

关键词： central Jordan Valley salt buildup soil health soil management unsustainable agriculture practices

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

Projective Hilbert modules and sequential approximations

引用

Science China Mathematics 2025年第1期 137-168页

作者： Lawrence g.Brown Huaxin Lin Department of Mathematics Purdue University Department of Mathematics East China Normal University Department of Mathematics University of Oregon Shanghai Institute for Mathematics and Interdisciplinary Sciences

We show that when A is a separable C*-algebra,every countably generated Hilbert A-module is projective（with bounded module maps as morphisms）.We also study the approximate extensions of bounded module *** the case where A is a σ-unital simple C*-algebra with strict comparison,and every strictly positive lower semicontinuous affine function on quasitraces can be realized as the rank of an element in the Cuntz semigroup,we show that the Cuntz semigroup is equivalent to unitarily equivalent classes of countably generated Hilbert A-modules if and only if A has stable rank one.

关键词：

来源：

同方期刊数据库

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：