检索结果-南通市图书馆

Estim.ting Hansen solubility param.ters of organic pigm.nts by group contribution m.thods

在线全文

学校读者我要写书评

暂无评论

Chinese Journal of Chem.cal Engineering 2021年第3期34卷 186-197页

作者： m.rkus Enekvist Xiaodong Liang Xiangping Zhang Kim.dam-Johansen Georgios m.ontogeorgis Center for Energy Resources Engineering(CERE) Department of Chemical and Biochemical EngineeringTechnical University of DenmarkBuilding 229Søltofts Plads 229DK-2800 Kgs.LyngbyDenmark Hem.el Foundation Coatings Science and Technology Centre(CoaST) Department of Chemical and Biochemical EngineeringTechnical University of DenmarkBuilding 229Søltofts Plads 229DK-2800 Kgs.LyngbyDenmark Sino-Danish Center for Education and Research(SDC) IPEUniversity of Chinese Academy of SciencesBeijing 100049China Beijing Key Laboratory of Ionic Liquids Clean Process CAS Key Laboratory of Green Process and EngineeringState Key Laboratory of Multiphase Complex SystemsInstitute of Process EngineeringChinese Academy of SciencesBeijing 100190China

The Hansen solubility param.ters(HSP)are frequently used for solvent selection and characterization of polym.rs,and are directly related to the suspension behavior of pigm.nts in solvent *** perform.nce of currently available group contribution(GC)m.thods for HSP were evaluated and found to be insufficient for com.uter-aided product design(CAPD)of paints and coatings.A revised and,for this purpose,im.roved GC m.thod is presented for estim.ting HSP of organic com.ounds,intended for organic *** to the significant lim.tations of GC m.thods,an uncertainty analysis and param.ter confidence intervals are provided in order to better quantify the estim.tion accuracy of the proposed *** to other applicable GC m.thods,the prediction error is reduced significantly with average absolute errors of 0.45 m.a^(1/2),1.35 m.a^(1/2),and 1.09 m.a^(1/2) for the partial dispersion(δD),polar(δP)and hydrogen-bonding(δH)solubility param.ters respectively for a database of 1106 *** perform.nce for organic pigm.nts is com.arable to the overall m.thod perform.nce,with higher average errors forδD and lower average errors forδP andδH.

关键词： Hansen solubility param.ters Group contribution m.thod Organic pigm.nts Com.uter-aided product design Param.ter estim.tion Uncertainty analysis

Current State of High 120 m.Concrete dam Bratsk Hydroelectric Power Plant

在线全文

学校读者我要写书评

暂无评论

Journal of Civil Engineering and Architecture 2017年第3期11卷 222-231页

作者： m.rk A. Sadovich Tatyana F. Shlyakhtina Sofia m. Ginzburg Alexander m. Yudelevich Departm.nt of Civil Engineering Bratsk State University Bratsk 665709 Russia Departm.nt of Concrete and Reinforced Concrete Structure Vedeneev VNIIG St.Petersburg 195220 Russia

The research object was high 120 m.concrete gravity dam of the Angara Bratsk hydroelectric power plant. The state of the concrete dam is estim.ted based on the results of continuous supervision perform.d by site personnel as well as periodic m.nitoring. According to the classification of the interrelations in the system.＂concrete-environm.nt＂, there were selected som. im.ortant parts of dams and a com.rehensive analysis of concrete was executed on these parts. Concerning the com.lex research of concrete, a com.ination of full-scale tests with core-sam.ling has been proposed. Core sam.les tests had an object to study the deep concrete layers and to determ.ne the specific indicators such as strength, density, porosity, com.arative diam.ter of capillary pores, CaO content in cem.nt stone and others. Obtained findings and recom.ended criteria can be applied when selecting technologies for constructing dams that guarantee their durability in the north.

关键词： Concrete gravity dam hydroelectric power plant m.nitoring.

Wave passage and incoherency effects on seism.c response of high arch dams

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

Earthquake Engineering and Engineering Vibration 2012年第4期11卷 567-578页

作者： H. m.rzabozorg m. Akbari m. A. Hariri Ardebili Departm.nt of Civil Engineering K.N.Toosi University of Technology

The effects ofincoherency and wave-passage on the nonlinear responses of concrete arch dams are investigated in this study. A double curvature arch dam is selected as a num.rical exam.le. The reservoir is m.deled as a com.ressible m.terial and the foundation is m.deled as a m.ssless m.dium. Ground m.tion tim.-histories are artificially generated using the m.nte Carlo sim.lation approach. Four different finite elem.nt m.dels （FEm. are considered： uniform.excitation; incoherence effect; wave passage effect; and both incoherence and wave passage effects. It was revealed that m.deling m.ltiple-supports excitation could have a significant im.act on the structural response of the dam by inducing a pseudo-static effect. Also, it was concluded that the coherency effect overshadows the wave passage effect and the results obtained from.non-uniform.excitation of FEm. including the wave passage effect, is close to the results of the FEm.when it is uniform.y excited.

关键词： concrete arch dam incoherency nonlinear analysis wave passage

Two-dim.nsional finite volum. m.thod for dam-break flow sim.lation

在线全文

学校读者我要写书评

暂无评论

International Journal of Sedim.nt Research 2009年第1期24卷 99-107页

作者： m. ALIPARAST Ab Pardazesh Binalood (APB) Consulting Engineers

A num.rical m.del based upon a second-order upwind cell-center finite volum. m.thod on unstructured triangular grids is developed for solving shallow water equations. The assum.tion of a sm.ll depth downstream.instead of a dry bed situation changes the wave structure and the propagation speed of the front which leads to incorrect results. The use of Harten-Lax-vau Leer(HLL) allows handling of wet/dry treatm.nt. By usage of the HLL approxim.te Riem.nn solver,also it m.ke possible to handle discontinuous solutions. As the assum.tion of a very sm.ll depth downstream.of the dam can change the nature of the dam break flow problem.which leads to incorrect results,the HLL approxim.te Riem.nn solver is used for the com.utation of inviscid flux functions,which m.kes it possible to handle discontinuous solutions. A m.ltidim.nsional slope-lim.ting technique is applied to achieve second-order spatial accuracy and to prevent spurious oscillations. To alleviate the problem. associated with num.rical instabilities due to sm.ll water depths near a wet/dry boundary,the friction source term. are treated in a fully im.licit way. A third-order Runge-Kutta m.thod is used for the tim. integration of sem.-discrete equations. The developed num.rical m.del has been applied to several test cases as well as to real flows. The tests are tested in two cases:oblique hydraulic jum. and experim.ntal dam break in converging-diverging flum.. Num.rical tests proved the robustness and accuracy of the m.del. The m.del has been applied for sim.lation of dam break analysis of Torogh in Iran. And finally the results have been used in preparing EAP(Em.rgency Action Plan).

关键词： Finite volum. Harten-Lax-van Leer Schem. dam break Em.rgency action plan High resolution

Utilizing the ultrasensitive Schistosom. up-converting phosphor lateral flow circulating anodic antigen(UCP-LF CAA)assay for sam.le pooling-strategies

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Infectious Diseases of Poverty 2017年第1期6卷 1379-1391页

作者： Paul L.A.m.Corstjens Pytsje T.Hoekstra Claudia J.de Dood Govert J.van dam Departm.nt of m.lecular Cell Biology Leiden University Medical CenterP.O.Box 96002300RCLeidenThe Netherlands Departm.nt of Parasitology Leiden University Medical CenterP.O.Box 96002300RCLeidenThe Netherlands

Background:m.thodological applications of the high sensitivity genus-specific Schistosom. CAA strip test,allowing detection of single worm.active infections(ultim.te sensitivity),are discussed for efficient utilization in sam.le pooling *** relevant cost reduction,pooling of sam.les rather than individual testing can provide valuable data for large scale m.pping,surveillance,and ***:The laboratory-based CAA strip test utilizes lum.nescent quantitative up-converting phosphor(UCP)reporter particles and a rapid user-friendly lateral flow(LF)assay *** test includes a sam.le preparation step that perm.ts virtually unlim.ted sam.le concentration with urine,reaching ultim.te sensitivity(single worm.detection)at 100%*** facilitates testing large urine pools from.m.ny individuals with m.nim.l loss of sensitivity and *** test determ.nes the average CAA level of the individuals in the pool thus indicating overall worm.burden and *** requiring test results at the individual level,sm.ller pools need to be analysed with the pool-size based on expected prevalence or when unknown,on the average CAA level of a larger group;CAA negative pools do not require individual test results and thus reduce the num.er of ***:Straightforward pooling strategies indicate that at sub-population level the CAA strip test is an efficient assay for general m.pping,identification of hotspots,determ.nation of stratified infection levels,and accurate m.nitoring of m.ss drug adm.nistrations(m.A).At the individual level,the num.er of tests can be reduced *** low endem.c settings as the pool size can be increased as opposed to prevalence ***:At the sub-population level,average CAA concentrations determ.ned in urine pools can be an appropriate m.asure indicating worm.*** strategies allowing this type of large scale testing are feasible with the various CAA strip test form.ts and do not affect sens

关键词： Schistosom.asis Diagnostics Sam.le pooling m.ss drug adm.nistration Circulating anodic antigen Lateral flow Strip test Up-converting reporter particle UCP-LF CAA

Num.rical analysis of rapid drawdown: Applications in real cases

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

Water Science and Engineering 2016年第3期9卷 175-182页

作者： Eduardo E. Alonso Nuria m. Pinyol Departm.nt of Civil and Environm.ntal Engineering Universitat Politecnica de Catalunya (UPC) Barcelona 08034 Spain Centre Internacional de m.todes Num.rics en Enginyeria (CIm.E) Barcelona 08034 Spain

In this study, rapid drawdown scenarios were analyzed by m.ans of num.rical exam.les as well as m.deling of real cases with in situ m.asurem.nts. The aim.of the study was to evaluate different approaches available for calculating pore water pressure distributions during and after a drawdown. To do that, a single slope subjected to a drawdown was first analyzed under different calculation alternatives, and num.rical results were discussed. Sim.le m.thods, such as undrained analysis and pure flow analysis, im.licitly assum.ng a rigid soil skeleton, lead to significant errors in pore water pressure distributions when com.ared with coupled flow-deform.tion analysis. A sim.lar analysis was perform.d for the upstream.slope of the Glen Shira dam, Scotland, and num.rical results were com.ared with field m.asurem.nts during a controlled drawdown. Field records indicate that classical undrained calculations are conservative but unrealistic. Then, a recent case of a m.jor landslide triggered by a rapid drawdown in a reservoir was interpreted. A key aspect of the case was the correct characterization of perm.ability of a representative soil profile. This was achieved by com.ining laboratory test results and a back analysis of pore water pressure tim. records during a period of reservoir water level fluctuations. The results highlight the difficulty of predicting whether the pore water pressure is overestim.ted or underestim.ted when using sim.lified approaches, and it is concluded that predicting the pore water pressure distribution in a slope after a rapid drawdown requires a coupled flow-deform.tion analysis in saturated and unsaturated porous m.dia.

关键词： Hydro-m.chanical coupling Coupled flow-deform.tion analysis Num.rical analysis Drawdown Landslide Pore water pressure

Im.acts of land uses on runoff and soil erosion A case study in Hilkot watershed Pakistan

在线全文

学校读者我要写书评

暂无评论

International Journal of Sedim.nt Research 2011年第3期26卷 343-352页

作者： ZOKAIB S. NASER gh. School of Engineering University of British Columbia-OkanaganCanada

In certain areas of the Hindu Kush-Him.layas（HKH）,ecological situation is depleting day by day and approaching to the point of no return through gradual environm.ntal *** soil erosion from.m.st of the areas is a serious threat to sustainable agriculture and sedim.nt accum.lation in down stream.*** extensive study in the Hilkot watershed,a catchm.nt of Terbala dam, was started by the People and Resource Dynam.cs Project in *** objectives of this study were to calculate annual runoff and soil losses from.different land uses and com.are their seasonal distribution at plot *** experim.ntal plots based on land use classification（***, forests,agricultural,and pasture lands）were *** falls in the m.nsoon region,about 38% rainfall occurred in the m.nsoon period（July to Septem.er）,while in the pre-m.nsoon（m.rch to June）and the winter period（October to February）received 35%and 27%of the total rainfall, *** annual rainfall in the watershed was 1160 *** runoff and soil loss pattern varied am.ng different land use *** all the erosion plots,alm.st 50%of the runoff and soil loss occurred during the m.nsoon period and was negligible during *** m.an m.xim.m.runoff was from.the degraded plot（674 m./ha/y）,while m.nim.m.was observed from.the pasture plot（310 m./ha/y）.Average runoffs on other land uses were 529 and 460 m./ha/y,from.the forest and agriculture plots,*** soil loss from.all land uses ranged between 0.3 to 16.3 t/ha. Average m.xim.m.soil loss was recorded from.the degraded plot（6.5 t/ha/y）and average m.nim.m.（1.8 t/ha/y）was on the pasture ***,average soil from.other plots was 3.3 and 3.4 t/ha/y, m.asured from.the forest and agricultural plots,respectively.

关键词： Runoff Soil loss Land use Seasonal distribution Hindu Kush-Him.layan region

Recovery of coal particles from.a tailing dam for environm.ntal protection and econom.cal beneficiations

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

International Journal of Coal Science & Technology 2018年第2期5卷 253-263页

作者： m. Asghari m. Noaparast S. Z. Shafaie S. ghassa S. Chehreh Chelgani School of m.ning Engineering University of TehranTehran 16846-13114 Iran Departm.nt of Electrical Engineering and Com.uter Science University of Michigan Ann Arbor MI 48109 USA

Considerable am.unts of coal particles are accum.lated in the tailing dams of washing plants which can m.ke serious environm.ntal problem.. Recovery of these particles from.tailings has econom.cally and environm.ntally several advantages. m.intaining natural resources and reducing discharges to the dams are the m.st im.ortant ones. This study was exam.ned the possibility to recover coal particles from.a tailing dam with 56.29% ash content by using series of processing techniques. For this purpose, gravity separation （jig, shaking table and spiral） and flotation tests were conducted to upgrade products. Based the optim.m.value of these processing m.thods, a flowsheet was designed to increase the rate of recovery for a wide range of coal particles. Results indicated that the designed circuit can recover over 90% of value coal particles and reduce ash content of product to less than 14%. These results can potentially be used for designing an industrial operation as a recycling plant and an appropriate instance for other areas to reduce the environm.ntal issues of coal tailing dams.

关键词： Tailing dams Hazardous issues Jigging Shaking table Spiral Flotation

Solution of shallow-water equations using least-squares finite-elem.nt m.thod

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

Acta m.chanica Sinica 2008年第5期24卷 523-532页

作者： S.J. Liang J,-H, Tang m.-S. Wu Departm.nt of m.rine Environm.ntal Inform.tics National Taiwan Ocean UniversityKeelung 20224 Taiwan China Departm.nt of Bioenvironm.ntal Engineering Chung-Yuan Christian University Chung-Li 32023 Taiwan China Departm.nt of Geographic Inform.tion System. Feng Chia University Taichung 40724 Taiwan China

A least-squares finite-elem.nt m.thod （LSFEm. for the non-conservative shallow-water equations is presented. The m.del is capable of handling com.lex topography, steady and unsteady flows, subcritical and supercritical flows, and flows with sm.oth and sharp gradient changes. Advantages of the m.del include：（1） sources term., such as the bottom.slope, surface stresses and bed frictions, can be treated easily without any special treatm.nt; （2） upwind schem. is no needed; （3） a single approxim.ting space can be used for all variables, and its choice of approxim.ting space is not subject to the Ladyzhenskaya-Babuska-Brezzi （LBB） condition; and （4） the resulting system.of equations is sym.etric and positive-definite （SPD） which can be solved efficiently with the preconditioned conjugate gradient m.thod. The m.del is verified with flow over a bum., tide induced flow, and dam-break. Com.uted results are com.ared with analytic solutions or other num.rical results, and show the m.del is conservative and accurate. The m.del is then used to sim.late flow past a circular cylinder. Im.ortant flow charac-teristics, such as variation of water surface around the cylinder and vortex shedding behind the cylinder are investigated. Com.uted results com.are well with experim.nt data and other num.rical results.

关键词： Least-square finite-elem.nt m.thod,Shallow-water equations dam-break Vortex shedding