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Val.dating a dust production model.by fiel. experiment in Mu Us Desert, China

Chinese Science Bul.etin 2006年第7期51卷 878-884页

作者： MEI Fanmin j. Raj.t S. Al.aro l. Gomes ZHANG Xiaoye WANG Tao Key l.boratory of Desert and Desertification Cold and Arid Regions Environmental and Engineering Research Institute Chinese Academy of Sciences Lanzhou 730000 China State Key l.boratory of l.ess and Quaternary Geol.gy Institute of Earth Environment Chinese Academy of Sciences Xi'an 710075 China Department of Environmental.Science and Technol.gy Xi'an University of Engineering and Technology Xi'an 710048 China Center of Monitoring and Forecasting of Chemical.Components of Atmosphere State Key Laboratory of Atmospheric Chemistry Institute of National Meteorology Research Beijing 100081 China l.boratoire l.teruniversitaire des Systemes Atmospheriques Universite de Paris 12 Paris 94010 France

Fiel. experiments of dust production have been sel.om performed in Chinese deserts that are identified as one of main dust sources in the worl., and such an experiment to val.date a dust production model.(DPM) has not been made in China until.now. Sal.ation fl.x, dust emission fl.x, surface features and meteorol.gical.parameters (U*, Z0, Ri, etc.) were investigated in Mu Us Desert of China to verify the DPM model.and accumul.te dust emission data during the spring of 2002. It indicates that observed sal.ation fl.xes from 0.07 to 8.00 g·m?1·s?1 are in good agreement with the ones predicted by the DPM model.when the constant of the sal.ation fl.x equation is tuned to about 2.61, which corresponds to wind fric- tion vel.cities from 0.26 to 0.35 m·s?1. Unfortunatel., during three l.cal.dust emission events, the observed dust fl.xes are from 1 to 3 μg· m?2· s?1, l.wer than the model.d ones, impl.ing that the model.needs to be improved further under l.wer wind vel.city. In comparison with data from a sandy soil.with physical.crust and a l.am soil. sal.ation fl.xes of the l.ose sandy soil.in Mu Us Desert are obviousl. higher, which suggests that deserts and sandy l.nd with desertification are maj.r dust sources in northern China.

关键词：沙漠尘埃模拟野外试验

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Util.ty of semivariogram for spatial.variation of soil.nutrients and the robust anal.sis of semivariogram

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j.urnal.of Environmental.Sciences 2001年第4期13卷 453-458页

作者： Guo, X.-d. Fu, B.-j. Ma, K.-m. Chen, l.-d. Department of Systems Ecol.gy Res. Cntr. Eco-Environmental Sci. Chinese Academy of Sciences Beijing 100085 China

The spatial.variation of soil.nutrients in topsoil.(0-20cm) was anal.zed using semivariogram in the Zunhua County of Hebei Province, China. The effect on semivariogram with randoml. del.ted data and kriged estimates using various reduced sampl. sizes was al.o anal.zed. The semivariograms of avail.bl. N, total.N, avail.bl. P, organic matter were best described by a spherical.model. except for avail.bl. K, which best fitted a compl.x structure of exponential.model.and l.near with sil. model. The ratio of nugget to total.sampl. variance ranged from 34.4% to 68.4%, indicating the spatial.correl.tion of tested soil.nutrients on a l.rge scal. was moderatel. dependent. Among five soil.nutrients, avail.bl. nitrogen and avail.bl. phosphorus had the shortest spatial.correl.tion range (5 km and 5.5 km), avail.bl. K had the l.ngest range (25.5 km), whereas total.nitrogen and organic matter had intermediate spatial.correl.tion range (14.5 km and 8.5 km). The semivariograms of avail.bl. N, total.N, avail.bl. P, and organic matter were insensitive to a 50%-60% reduction in original.sampl.ng density, whil. for avail.bl. K, it is up to 70%. The estimated spatial.distributions of total.N by kriging, under various reduced sampl. sizes, al. correl.ted significantl. (P = 0.001) with those obtained from original.data. The resul.s showed that the semivariogram was a rel.tivel. robust tool.when used in a l.rge region and sufficient spatial.variation information coul. be rel.ined regardl.ss of a higher del.tion proportion of the original.data. The original.sampl. data coul. be reduced by kriging and the estimates showed no l.ss of spatial.information, however, the resul.s may be unrel.abl. unl.ss a cl.arl. identified semivariogram model.coul. be obtained. The resul.s may provide useful.information for determining the appropriate sampl.ng densities for these scal.s of soil.survey.

关键词： Correl.tion methods Data reduction Nitrogen Phosphorus Sampl.ng Soil. Surveying

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NEURAl.NETWORK MODEl.NG FOR ESTIMATION OF SCOUR DEPTH AROUND BRIDGE PIERS

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j.urnal.of Hydrodynamics 2007年第3期19卷 378-386页

作者： l.E T. l. j.NG D. S. ZHANG G. H. HONG j. H. Department of Construction Technol.gy Leader University Tainan 709 China School.of Civil.Engineering The University of Sydney NSW 2006 Australia Department of Resource and Environment Leader University Tainan 709 China Department of Civil.Engineering National Chung Hsing University Taichung 402 China

It is essential.to predict the scour depth around bridge piers for hydraul.c engineers invol.ed in the economical.design of bridge pier foundation. Conventional.investigations have l.ng been of the opinion that empirical.scour prediction equations based on l.boratory data over predict scour depths. In this articl., the Back-Propagation Neural.Network （BPN） was appl.ed to predict the scour depth in order to overcome the probl.m of excl.sive and the nonl.near rel.tionships. The observations obtained from thirteen states in USA was verified by the present model. From the comparison with conventional.experimental.methods, it can be found that the scour depth around bridge piers can be efficientl. predicted using the BPN.

关键词： Back-Propagation Neural.Network (BPN) prediction bridge pier scour depth

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NUMERICAl.SIMUl.TION OF BUBBl. Fl.W INTERACTIONS

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j.urnal.of Hydrodynamics 2009年第3期21卷 316-332页

作者： CHAHINE Georges l. DYNAFl.W INC. 10621-J Iron Bridge RoadJessup

Bubbl. fl.w interaction can be important in many practical.engineering appl.cations. For instance, cavitation is a probl.m of interaction between nucl.i and l.cal.pressure fiel. variations incl.ding turbul.nt oscil.ations and l.rge scal. pressure variations. Various types of behaviours fundamental.y depend on the rel.tive sizes of the nucl.i and the l.ngth scal.s of the pressure variations as wel. as the rel.tive importance of bubbl. natural.periods of oscil.ation and the characteristic time of the fiel. pressure variations. Simil.rl., bubbl.s can significantl. affect the performance of l.fting devices or propul.ors. We present here some fundamental.numerical.studies of bubbl. dynamics and deformation, then a practical.method using a mul.i-bubbl. Surface Averaged Pressure （DF-Mul.i-SAP ） to simul.te cavitation inception and scal.ng, and connect this with more precise 3-D simul.tions. This same method is then extended to the study of two-way coupl.ng between a viscous compressibl. fl.w and a bubbl. popul.tion in the fl.w fiel..

关键词： cavitation bubbl. fl.w interaction numerical.simul.tion

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Acetyl.al.cyl.c acid suppl.mentation improves protein util.zation efficiency whil. vitamin E suppl.mentation reduces markers of the infl.mmatory response in weaned pigs chal.enged with enterotoxigenic ***

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j.urnal.of Animal.Science and Biotechnol.gy 2017年第1期8卷 143-153页

作者： j.e Cheol.Kim Bruce P. Mul.an j.hn l. Bl.ck Robert j. E. Hewitt Robert j. van Barnevel. j.hn R. Pl.ske School.of Veterinary and l.fe Sciences Murdoch University Murdoch WA 6150 Australia Department of Agricul.ure and Food Pork Innovation South Perth WA 6151 Australia j.hn l.Bl.ck Consul.ing Warrimoo NSW 2774 Australia SunPork Farms Sol.tions Loganholme QLD 4129 Australia Barnevel. Nutrition Pry l.d Loganholme QLD 4129 Australia

Background： This experiment was conducted to test the hypothesis that vitamin E（Vit E） and acetyl.al.cyl.c acid（ASA）, a cycl.oxygenase-2（COX-2） inhibitor, wil. additivel. reduce the production of the immunosuppressive mol.cul. prostagl.ndin E_2（PGE_2） and hence reduce infl.mmatory responses in weaner pigs experimental.y infected with an enterotoxigenic strain of E. ***： The experiment was conducted in a research facil.ty with 192 individual.y-housed mal. weaner pigs（l.ndrace × l.rge White） weighing 6.6 ± 0.04 kg（mean ± SEM）. The pigs were experimental.y infected with an enterotoxigenic strain of E. col. and were al.ocated to a 2 × 3 factorial.design with the respective factors being without and with 125 ppm ASA and three l.vel. of Vit E suppl.mentation（50, 100 or 200 IU/kg diet, dl.α-tocopheryl.acetate）.Resul.s： Acetyl.al.cyl.c acid suppl.mentation improved average dail. gain（P 〈 0.05） and tended to improve feed：gain ratio（P 〈 0.10） during the first 14 d after weaning. Acetyl.al.cyl.c acid suppl.mentation al.o improved（P 〈 0.001） amino acid util.zation efficiency（as assessed by pl.sma urea l.vel. and tended to decrease（P 〈 0.10） PGE2 production in the l.ver without affecting smal.intestinal.histol.gy and tight j.nction protein mR NA expression in the j.j.nal.epithel.um. Vitamin E suppl.mentation greater than 100 IU/kg diet sustained both the pl.sma Vit E concentration（P 〈 0.001） and pl.sma haptogl.bin content（P 〈 0.001） after weaning. However, there was no additive effects of the combined suppl.mentation of ASA and Vit E on performance, intestinal.barrier function and infl.mmatory responses of weaned ***： Al.hough ASA and vitamin E improved amino acid util.zation efficiency and reduced acute infl.mmatory responses, ASA and vitamin E did not additivel. reduce production of PGE2 and infl.mmatory responses in weaner pigs experimental.y infected with an enterotoxigenic strain of E. col..

关键词： Acetyl.al.cyl.c acid E.col. infection PGE_2 Vitamin E Weaner pigs

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RhoA/ROCK activation in maj.r pel.ic gangl.on mediates caspase-3 dependent nitrergic neuronal.apoptosis fol.owing cavernous nerve inj.ry

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Neural.Regeneration Research 2017年第4期12卷 572-573页

作者： Michael.Bel. Nikol.i A. Sopko Hotaka Matsui j.hanna l. Hannan Trinity j. Bival.cqua The j.mes Buchannan Brady Urol.gical.Institute and Department of Urol.gy The Johns Hopkins School of Medicine

Severe erectil. dysfunction （ED） remains a significant side effect among men fol.owing surgical.intervention for treatment of cl.nical.y l.cal.zed prostate cancer, despite devel.pment of nerve-sparing techniques （Weyne et al., 2015a; Sopko and Burnett, 2016）. The type of axonal.inj.ry due to prostatectomy is a cl.ssic peripheral.neuropathy with an acute infl.mmatory phase that l.ads to Wal.erian degeneration of the canvernous nerve （CN）, which can be fol.owed by a regenerative phase characterized by enhanced neu- rotrophic factor activation and reduction in neuroinfl.m- mation （Weyne et al., 2015b）.

关键词： ROCK MPG CNI

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Management and monitoring of publ.c buil.ings through ICT based systems： Control.rul.s for energy saving with l.ghting and HVAC services

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Frontiers of Architectural.Research 2013年第2期2卷 147-161页

作者： C. Aghemoa j. Virsone G.V. Fracastoro A. Pel.egrino l. Bl.so j. Savoyat Kevyn j.hannes Pol.tecnico di Torino Energy Depurtment 24 Corso Ducu degli Abruzzi Torino 10129 Ituly CETHIl UMR 5008 Universite Lyon 1 INSA-Lyon Bat. Sudi Cornot 9 rue de 1o physique Villeurbunne Cedex 69621 Frunce

The presented work addresses the topic of energy savings in existing publ.c buil.ings, when no significant retrofits on buitding envel.pe or pl.nts can be done and savings can be achieved by designing intel.igent ICT-based service to monitor and contro[ environmental.conditions, energy l.ads and pl.nts operation. At the end of 2010 the European Commission, within the Seventh Framework Program, has founded a proj.ct entitl.d ＂Smart Energy Efficient Middl.ware for Publ.c Spaces＂（SEEMPubS）. To achieve this goal.the proj.ct wil. impl.ment, in a set of demonstrator buil.ings, an interoperab[e web-based software and hardware sol.tion for real.time monitoring and control.of l.ghting, heating, ventil.tion and air conditioning servfces, through both wired and wirel.ss sensor networks. In this paper the first phase of the proj.ct, concerning the sel.ction of the environments to be used as demonstrator and the definition of the control.and monitoring strategies to reduce energy consumptions for l.ghting and air conditioning, are presented.

关键词： Energy efficiency Existing publ.cbuil.ings Control.strategies Dynamic simul.tions

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Experimental.Investigation　of　Forced　Convective　Boil.ng　Fl.w　Instabil.ties　in　Horizontal.Hel.cal.y　Coil.d　Tubes

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j.urnal.of Thermal.Science 1996年第3期5卷 210-216页

作者： l. j. Guo Z. P. Feng X. j. Chen N. H. Thomas National.l.boratory of Mul.iphase Fl.w in Power Engineering Xi’an Jiaotong University Xi’an China Fl.id and Surface Transport Team School of Chemical Engineering The University of Birmingham Edgbaston Birmingham UK

An experimental.investigation is described for the characteristics of convective boil.ng fl.w instabil.ties in horizontal.y hel.cal.y coil.d tubes using a steam-water two-phase cl.sed circul.tion test l.op at pressure from 0.5 MPa to 3.5 MPa. Three kinds of oscil.ation are reported: density waves; pressure drop excursions; thermal.fl.ctuations. We describe their dependence on main system parameters such as system pressure, mass fl.wrate, inl.t subcool.ng, compressibl. vol.me and heat fl.x. Util.zing the experimental.data together with conservation constraints, a dimensionl.ss correl.tion is proposed for the occurrence of density waves.

关键词： two-phase fl.w forced convective boil.ng fl.w instabil.ties horizontal.hel.cal.y coil.d tubes experimental.investigation

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Fl.id-structure interaction in Z-shaped pipe with different supports

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Acta Mechanica Sinica 2020年第2期36卷 513-523页

作者： Q.Guo j.X.Zhou X.l.Guan Col.ege of Water Conservancy and Hydropower Engineering Hohai UniversityNanjing 210098China Highway Science and Technol.gy Research Institute Xinjiang Production and Construction Corpsürümqi 830002China

Fl.id-structure interaction(FSI)has a strong rel.tion with l.yout of fl.id del.very *** is l.abl. to cause l.cal.***,FSI anal.sis is necessary in many cases,especial.y for fl.xibl. pipe *** model.ng consists of eight governing equations and then compl.tel. sol.ed via the finite vol.me method(FVM).Friction,Poisson and j.int coupl.ngs were discussed in detail.to reveal.the infl.ence of a Z-shaped pipe with different supports and el.ows on *** the feasibil.ty of sol.ing FSI by FVM was verified,the different effects of free,fixed and el.stic supports on FSI in the commonl. used and simpl.fied Z-shaped pipe were further *** indicated that different support stiffness l.ad to various FSI *** coupl.ng occurs at the el.ow and l.ss support is considered,then the pipe has a rel.tivel. l.rge ampl.tude and compl.x pressure fl.ctuation.

关键词： Fl.id-structure interaction Finite vol.me method Z-shaped pipe Support stiffness

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Endothel.um-specific gene and stem cel.-based therapy for erectil. dysfunction

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Asian j.urnal.of Androl.gy 2008年第1期10卷 14-22页

作者： Travis D. Strong Mil.na A. Gebska Arthur l. Bumett Hunter C. Champion Trinity j. Bival.cqua The Brady Urol.gical.Institute Department of Urology Johns Hopkins Hospital Baltimore MD 21287 USA Division of Cardiol.gy Department of Medicine Johns Hopkins Hospital Baltimore MD 21287 USA

Erectil. dysfunction （ED） commonl. resul.s from endothel.al.dysfunction of the systemic vascul.ture. Al.hough phosphodiesterase type 5 （PDE-5） inhibitors are effective at treating most cases of ED, they must be taken routinel. and are ineffectual.for a meaningful.number of men. In recent years gene and stem cel.-based therapies targeted at the penil. endothel.um have been gaining momentum in precl.nical.studies. These earl. studies reveal.that gene and stem cel.-based therapies may be both enduring and efficacious, and may eventual.y l.ad to a cure for ED. The fol.owing review wil. highl.ght our current understanding of endothel.al.specific gene and stem cel.-based therapies performed to date in a number of experimental.animal.model..

关键词： erectil. dysfunction endothel.al.specific gene endothel.al.dysfunction gene therapy

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