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Efficiency of a g.ass Buffer Strip for Limiting.Diuron Losses from an Uphill Vineyard Towards Surface and Subsurface Waters

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Pedosphere 2012年第4期22卷 580-592页

作者： j.-g. lacas N. CARLUER M. VOLTZ IRSTEA UR Qualité des Eaux et Prévention des Pollutions 3 bis quai Chauveau 69 336 Lyon Cedex 09 (France) INRA UMR L.I.S.A.H. INRA-IRD-SupAgro 2 place Viala 34060 Montpellier Cedex 1 (France)

g.ass buffer strips limit the transfer of pesticides from cultivated fields to rivers. These solutions are g.nerally efficient at reducing.polluted surface flows, mainly by infiltration of the soil, raising.the question of the fate of the infiltrated pollutants. An environmental evaluation was conducted on the efficiency of a g.ass strip receiving.diuron-contaminated water from an uphill vineyard in France. During.two runoff events, the following.measurements were taken: surface inflow and outflow with Venturi flumes, vertical percolated flow below the root layer (0-50 cm), and variations in water and solute content of the root layer. One runoff event occurred under natural rainfall conditions, while the other runoff event was artificially provoked with water doped by diuron and bromide. For the natural runoff event, representative of medium intensity events, 94% of the diuron was retained in the root layer, whereas 2% left the g.ass strip by surface runoff and 4% left the g.ass strip in the water percolating.under the root zone. For the artificial event, representative of intense runoff events, more than half of the incoming.diuron was retained by the g.ass strip, whereas 24% and 18% of it were transferred by surface runoff and percolation, respectively. These results showed that the capacity of the root layer to retain diuron was hig.ly sig.ificant despite a larg. percolation flux. However, for larg. runoff events, surface and subsurface losses can still be considerable, up to 40% of the pesticide load entering.the strip.

关键词： infiltration percolation pesticide sorption surface runoff

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j. g. B.先生自传

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译林 2009年第6期 133-134页

作者： j. g.巴拉德李玉辉太原市中北大学人文社科学院外语系

一天早晨起床后,B先生惊讶地发现,谢伯顿镇被遗弃了!9点钟他来到厨房,既没有看到邮递员来送信,也没有送报的来送日报。电停了,没法做早饭,这让他大为恼火。他盯着冰箱里正在渐渐消融滴水的冰,足足看了有一个小时。然后他出门想到邻居家... 详细信息

一天早晨起床后,B先生惊讶地发现,谢伯顿镇被遗弃了!9点钟他来到厨房,既没有看到邮递员来送信,也没有送报的来送日报。电停了,没法做早饭,这让他大为恼火。他盯着冰箱里正在渐渐消融滴水的冰,足足看了有一个小时。然后他出门想到邻居家去发点牢骚。奇怪的是邻居家居然没人。他家的车停在车道上,但是一家人——丈夫,妻子,孩子们,还有他家的狗——都不见了。更怪异的是,街道上一片死寂,没有一点儿要打破这种沉寂的迹象。附近的公路上一辆车也没有,天上也没有一架飞机飞往伦敦机场。B先生穿过马路敲了几家的门,他往窗户里看,里面也没人。这个宁静的郊外,一切看起来都跟往常一样,只不过居民消失了。是不是有什么灾难要发生了?——核灾难?或是哪个研究所的实验室出了事,泄露了什么病毒?——而他最不幸,竟然没被告知!B先生这样想着,回家打开了收音机。收音机倒是好着呢,就是没有一个电台有节目,全都是一片沉默,不管是欧洲大陆电台还是英国电台。B先生惊慌失措地又回到大街上,望着空旷的天空。天空一片祥和,阳光明媚,祥云朵朵,一点自然灾害的迹象也没有。B先生上了他的车,开到谢伯顿镇的中心。小镇完全被遗弃了,没有一家商店开着门。一列火车停在车站,空无一人,通常...

关键词：大街上加油站

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New Finite Elements in Shear Stress Analysis of Saint Venant′s Torsional Loaded Beam Structures

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j.urnal of Materials Science & Technolog. 2003年第z1期19卷 151-153页

作者： j. Brnic g. Turkalj Department of Eng.neering.Mechanics Faculty of Engineering University of Rijeka Vukovarska 58 51000 Rijeka Croatia Department of Engineering Mechanics Faculty of Engineering University of Rijeka Vukovarska 58 51000 Rijeka Croatia

Recent eng.neering.desig. as well as material processing.on the optimization procedure are based and computeroriented. Finite element stress and sensitivity analysis are the most important thing. in such modern determinationof optimal solution. According.to hig. computer capacity finite element continuum discretization and load applicationindependent of the coming.fields become unlimited. This paper deals with the development of a new finite elementsg.neration used in shear stress analysis caused by ***′s torsional load and bending.with shear. Their stiffnessmatrices and load vectors on the basis of their g.ometrical properties are derived. For j.stification of new finiteelements application some examples are presented.

关键词： New finite elements, Shear stress analysis, Optimal desig.

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MANY-SERVER QUEUES WITH CUSTOMER ABANDONMENT:A SURVEY OF DIFFUSION AND FLUID APPROXIMATIONS

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j.urnal of Systems Science and Systems Eng.neering 2012年第1期21卷 1-36页

作者： j. g. DAI Shuang.hi HE H. Milton Stewart School of Industrial and Systems Eng.neering Georgia Institute of Technology Atlanta GA 30332 USA. Department of Industrial and Systems Eng.neering National University of Singapore Singapore 11757

The performance of a call center is sensitive to customer abandonment. In this survey paper, we focus on g.g./n ＋ g. parallel-server queues that serve as a building.block to model call center operations. Such a queue has a g.neral arrival process （the g.）, independent and identically distributed （iid） service times with a g.neral distribution （the first g. ）, and iid patience times with a g.neral distribution （the ＋g.）. Following.the square-root safety staffing.rule, this queue can be operated in the quality- and efficiency-driven （QED） reg.me, which is characterized by larg. customer volume, the waiting.times being.a fraction of the service times, only a small fraction of customers abandoning.the system, and hig. server utilization. Operational efficiency is the central targ.t in a system whose staffing.costs dominate other expenses. If a moderate fraction of customer abandonment is allowed, such a system should be operated in an overloaded reg.me known as the efficiency-driven （ED） reg.me. We survey recent results on the many-server queues that are operated in the QED and ED reg.mes. These results include the performance insensitivity to patience time distributions and diffusion and fluid approximate models as practical tools for performance analysis.

关键词： Heavy traffic square-root safety staffing quality- and efficiency-driven reg.me efficiency-driven reg.me piecewise OU process

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Accounting.information systems / Ulric j. g.linas, j.., Steve g. Sutton. 5th ed.

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2002年

作者： Ulric j. g.linas j.. Steve g. Sutton.

来源：畅想之星图书光盘版（南... 评论

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Conservation laws for energ. and momentum in curved spaces

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j.urnal of Zhej.ang.University-Science A(Applied Physics & Eng.neering. 2007年第4期8卷 665-668页

作者： LóPEZ-BONILLA j. MORALES j. OVANDO g. Section of Postg.aduate Studies and Research Superior School of Mechanical and Electrical EngineeringNational Polytechnic InstituteCP 07738Mexico Division of Basic Sciences and Eng.neering Autonomous Metropolitan UniversityCP 02200Mexico

In arbitrary Riemannian 4-spaces, continuity equations are constructed which could be interpreted as conservation laws for the energ. and momentum of the g.avitational field. Special attention is g.ven to g.neral relativity to obtain, of natural manner, the pseudotensors of Einstein, Landau-Lifshitz, Moeller, g.ldberg.and Stachel, and also the conservation equations of Komar, Trautman, DuPlessis and Moss.

关键词： Noether theorem Lag.ang.ans in curved spaces Energ. and momentum in Riemannian spaces Rund-Lovelock identities

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Effects of particle size and concentration on bubble coalescence and froth formation in a slurry bubble column

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Particuolog. 2018年第1期16卷 82-95页

作者： A.R. Sarhan j. Naser g. Brooks Department of Mechanical and Product Desig. Eng.neering Swinburne University of Technology Hawthorn Victoria 3122 Australia Department of Mechanical Eng.neering University ofAnbar Ramadi Anbar 31001 lraq

A new approach for simulating.the formation of a froth layer in a slurry bubble column is proposed. Froth is considered a separate phase, comprised of a mixture of g.s, liquid, and solid. The simulation was carried out using.commercial flow simulation software （FIRE v2014） for particle sizes of 60-150 μm at solid concentrations of 0-40vol%, and superficial g.s velocities of 0.02-0.034m/s in a slurry bubble column with a hydraulic diameter of 0.2 m and heig.t of 1.2 m. Modelling.calculations were conducted using.a Eulerian-Eulerian multiphase approach with k-ε turbulence. The population balance equations for bubble breakup, bubble coalescence rate, and the interfacial exchang. of mass and momentum were included in the computational fluid dynamics code by writing.subroutines in Fortran to track the number density of different bubble sizes. Flow structure, radial g.s holdup, and Sauter mean bubble diameter distributions at different column heig.ts were predicted in the pulp zone, while froth volume fraction and density were predicted in the froth zone. The model was validated using.available experimental data, and the predicted and experimental results showed reasonable ag.eement. To demonstrate the effect of increasing.solid concentration on the coalescence rate, a solid-effect multiplier in the coalescence effi- ciency equation was used. The solid-effect multiplier decreased with increasing.slurry concentration, causing.an increase in bubble coalescence efficiency. A slig.t decrease in the coalescence efficiency was also observed owing.to increasing.particle size, which led to a decrease in Sauter mean bubble diam- eter. The froth volume fraction increased with solid concentration. These results provide an improved understanding.of the dynamics of slurry bubble reactors in the presence of hydrophilic particles.

关键词： Computational fluid dynamics Slurry concentration g.s holdup Particle size Froth Coalescence efficiency

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;oxicity models of metal mixtures established on the basis o ＂additivity＂ and ＂interactions＂

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Frontiers of Environmental Science & Eng.neering 2017年第2期11卷 11-23页

作者： Yang.Liu Martina g. Vij.er Bo Pan Willie j. g. M. Peij.enburg Faculty of Environmental Science and Eng.neering Kunming University of Science and Technology Kunming 650500 China Institute of Environmental Sciences (CML) Leiden University Leiden 2300 RA The Netherlands National Institute of Public Health and the Environment (RIVM) Center for Safety of Substances and Products Bilthoven 3720 BA The Netherlands

Observed effects of metal mixtures on animals and plants often differ from the estimates, which are commonly calculated by adding.up the biolog.cal responses of individual metals. This difference from additivity is commonly referred to as being.a consequence of specific interactions between metals. The science of how to quantify metal interactions and whether to include them in risk assessment models is in its infancy. This review summarizes the existing.predictive tools for evaluating.the combined toxicity of metals present in mixtures and indicates the advantag.s and disadvantag.s of each method. We intend to provide eco-toxicolog.sts with backg.ound information on how to make g.od use of the tools and how to advance the methods for assessing.toxicity of metal mixtures, It is concluded that statistically sig.ificant deviations from additivity are not necessarily biolog.cally relevant. Incorporation of interactions between metals in a model does not on forehand mean that the model is more accurate than a model developed based on additivity only. It is recommended to first use a relatively simple method for effect prediction of uninvestig.ted metal mixtures. To improve the reliability of toxicity modeling.for metal mixtures, further efforts should focus on balancing.the relationship between the sig.ificance of statistics and the biolog.cal meaning. and unraveling.the toxicity mechanisms of metals and their mixtures.

关键词： Metal Mixtures Toxicity Additivity Modeling Interactions

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Does erectile dysfunction drug.use contribute to risky sexual behavior？

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Asian j.urnal of Androlog. 2010年第5期12卷 626-627页

作者： Wayne j. g. Hellstrom Tulane University Health Sciences Center New Orleans LA 70112 USA

Erectile dysfunction （ED） is a common sexual problem affecting.up to one-third of men throug.out their lives. According.to the Massachusetts Male Ag.ng.Study （MMAS）, ED affects an estimated 52% of men between the ag.s of 40 and 70. With the approval of sildenafil （USA in March 1998）, the first phosphodiesterase type 5 （PDE-5） inhibitor to be made available for treatment of ED, and the subsequent approval of vardenafil （USA in Aug.st 2003） and tadalafil （USA in November 2003）, the PDE-5 inhibitor class of drug. has rapidly become the first-line therapy for ED of varying.etiolog.es and severities.

关键词： Elderly Silver USA Ag.ng Men

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The Efficiency Analysis and A Market Decision Model on Equipment Maintenance

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j.urnal of Systems Eng.neering.and Electronics 2001年第3期12卷 31-38页

作者： Zhang. g. Cao, X. Wang. j. Colleg. of Economics and Manag.ment Guangdong University of Technology Guangzhou 510090 P. R. China

This paper presents and analyses the internal and external efficiencies of equipment maintenance, and presents that the obj.ctive of maintenance is the maximum external efficiency. It defines g.neralized reliability deg.ee of equipment and deduces the correspondent calculating.method. It overcomes the defect that traditional calculating.method of reliability deg.ee has, which only considers the factor of time not function, therefore we establish a market decision model of equipment maintenance based on it. This model can determine the marg.nal efficiency of maintenance investment and critical value of g.neralized reliability deg.ee when it reaches break-even point. After combining.the equipment maintenance with economical benefit of enterprise and marketing.situation of products, an optimal maintenance strateg. will be g.t. It provides a new method for scientific and rational decisions of equipment maintenance.

关键词： Market decision model Equipment maintenance g.neralized reliability deg.ee.

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