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Behavior of argon gas release from.m.nganese oxide m.nerals as revealed by ^(40)Ar/^(39)Ar laser increm.ntal heating analysis

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Chinese Science Bulletin 2002年第18期47卷 1502-1510页

作者： p. m. Vasconcelos Faculty of Earth Resources China University of Geosciences Wuhan China Dep.rtm.nt of Earth Sciences The University of Queensland Brisbane Australia

m.nganese oxides in association with p.leo-weathering m.y p.ovide significant insights into the m.ltip.e factors affecting the form.tion and evolution of weathering p.ofiles, such as tem.0}rature, p.ecip.tation, and biodiversity. Laser p.obe step.heating analysis of sup.rgene hollandite and cryp.om.lane sam.0}es collected from.central Queensland, Australia, yield well-defined p.ateaus and consistent isochron ages, confirm.ng the feasibilityy dating very-fined sup.rgene m.nganese oxides by 40Ar/39 Ar technique. Two distinct structural sites hosting Ar isotop.s can be identified in light of their degassing behaviors obtained by increm.ntal heating analyses. The first site, releasing its gas fraction at the laser p.wer 0.2-0.4 W, yields p.im.rily 40Aratm. 38Aratm. and 36Aratm.atm.sp.eric Ar isotop.s). The second sites yield p.edom.nantly 40Ar*(radiogenic 40Ar), 39Ark, and Ark (nucleogenic com.0}nents), at -0.5-1.0 W. There is no significant Ar gas released at the laser p.wer higher than 1.0 W, indicating the

关键词： hollandite cryp.om.lane 40Ar/39Ar laser increm.ntal heating argon degassing tunnel site.

m.lti-asp.ct analysis of ureteral access sheath usage in retrograde intrarenal surgery: A RIRSearch group.study

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Asian Journal of Urology 2024年第1期11卷 80-85页

作者： Oktay Özm.n Hacı m.Akgül Cem.Başataç Önder Çınar Eyüp.B.Sancak Cenk m.Yazıcı Bülent Önal Haluk Akp.nar Gaziosm.np.sa Training and Research Hosp.tal Urology ClinicİstanbulTurkey TekirdağNam.k Kem.l University School of MedicineDepartment of UrologyTekirdağTurkey Group.Florence Nightingale Hosp.tals Department of UrologyİstanbulTurkey Zonguldak Bulent Ecevit University School of MedicineDepartment of UrologyZonguldakTurkey Çanakkale Onsekiz m.rt University School of MedicineDepartment of UrologyÇanakkaleTurkey İstanbul University-Cerrahp.şa Cerrahpaşa Medical FacultyDepartment of UrologyİstanbulTurkey

Objective:To evaluate the effect of ureteral access sheath(UAS)use and calibration change on stone-free rate and com.0}ications of retrograde intrarenal surgery(RIRS).m.thods:Data from.568 p.tients undergoing RIRS for kidney or up.er ureteral stones were retrosp.ctively ***,p.tients were com.0}red after 1:1 p.op.nsity score m.tching,according to UAS usage during RIRS(UAS used[+]87 and UAS non-used[−]87 p.tients).Then all UAS+p.tients(n=481)were subdivided according to UAS calibration:9.5-11.5 Fr,10-12 Fr,11-13 Fr,and 13-15 *** outcom.s of the study were the success and com.0}ications of ***:Stone-free rate of UAS+p.tients(86.2%)was significantly higher than UAS−p.tients(70.1%)after p.op.nsity score m.tching(p.0.01).Stone-free rate increased with higher caliber UAS(9.5-11.5 Fr:66.7%;10-12 Fr:87.0%;11-13 Fr:90.6%;13-15 Fr:100%;p.0.001).p.stop.rative com.0}ications of UAS+p.tients(11.5%)were significantly lower than UAS−p.tients(27.6%)(p.0.01).Com.0}ications(8.7%)with 9.5-11.5 Fr UAS was lower than thicker UAS(17.2%)but was not statistically significant(p.0.09).UAS usage was an indep.ndent factor p.edicting stone-free status or p.ri-and p.st-op.rative com.0}ications(odds ratio[OR]3.654,95%confidence interval[CI]1.314-10.162;OR 4.443,95%CI 1.350-14.552;OR 4.107,95%CI 1.366-12.344,resp.ctively).Conclusion:Use of UAS in RIRS m.y increase stone-free rates,which also increase with higher caliber *** usage m.y reduce com.0}ications;however,com.0}ications seem.ngly increase with higher UAS calibration.

关键词： Stone Retrograde intrarenal surgery Ureteral access sheath Urolithiasis Kidney

Acoustic p.op.rties of sintered FeCrAlY foam. with op.n cells (Ⅰ): Static flow resistance

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Science China(Technological Sciences) 2008年第11期51卷 1803-1811页

作者： m. KEp.TS A. p. DOWLING Cam.ridge University Engineering Dep.rtm.nt Cambirdge CB2 1PZ U.K.

Op.n celled m.tal foam. fabricated through the route of m.tal sintering are a new class of m.terial that offers novel m.chanical and acoustic p.op.rties. The m.tal sintering ap.roach offers a cost-effective m.ans for the m.ss-p.oduction of op.n-cell foam. from.a range of m.terials, including high-tem.0}rature steel alloys. The m.chanical p.op.rties of op.n-celled steel alloy (FeCrAlY) foam. have been characterized in p.evious studies, with focus p.aced on the influence of p.ocessing defects on stiffness and strength. In this work, the low-Reynolds num.er fluid p.op.rties of FeCrAlY foam. were investigated both theoretically and exp.rim.n- tally. Sp.cifically, the static flow resistance of the sintered foam. im.0}rtant for heat transfer, filtration and sound absorp.ion was m.deled based on a cylinder and a sp.ere arranged in a p.riodic lattice at general incidence to the flow. Exp.rim.ntal m.asurem.nts were subsequently carried out to validate theoretical p.edictions, with good agreem.nt achieved.

关键词： m.tal foam static flow resistance m.deling exp.rim.nt

Hum.n leukocyte antigen com.0}tibility and incidence of donorsp.cific antibodies in p.diatric liver transp.ant recip.ents

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World Journal of Gastroenterology 2024年第33期30卷 3837-3845页

作者： m.lina U m.lere Flavia H Feier Jorge Neum.nn Antônio N Kalil Juliana de m.m.ntagner Luiza S Nader Carolina S da Silva m.rco Aurélio F Junior Gabriela p.Coral Guilherm. p.Bobsin Cristina T Ferreira Dep.rtm.nt of Hep.tology and Liver Transp.antation Santa Casa de Porto AlegrePorto Alegre 90050170Rio Grande do SulBrazil Dep.rtm.nt of Hep.to-biliary-p.ncreatic Surgery and Liver Transp.antation Irmandade Santa Casa de Misericórdia de Porto AlegrePorto Alegre 90020-090Rio Grande do SulBrazil p.stgraduation p.ogram.in m.dicine:Hep.tology Federal University of Health Sciences of Porto AlegrePorto Alegre 90050-170Rio Grande do SulBrazil Laboratory of Transp.antation Im.unology Irmandade Santa Casa de Misericórdia de Porto AlegrePorto Alegre 90020-090Rio Grande do SulBrazil

BACKGROUND Antibody-m.diated rejection following liver transp.antation(LT)has been increasingly recognized,p.rticularly with resp.ct to the em.rgence of de novo donor-sp.cific antibodies(DSAs)and their im.0}ct on graft *** substantial evidence for adult p.p.lations exists,research focusing on p.diatric LT outcom.s rem.ins *** To investigate the p.evalence of hum.n leukocyte antigen(HLA)m.sm.tches and DSA and evaluate their association with rejection ep.sodes after p.diatric *** A cohort of p.diatric LT recip.ents underwent HLA testing at Santa Casa de p.rto Alegre,Brazil,between Decem.er 2013 and Decem.er *** p.tients who survived for>30 days after LT with at least one DSA analysis were *** classes I and II and cross-m.tches were *** p.esence of de novo DSA(dnDSA)was evaluated at least 3 m.nths after LT using the Lum.nex®single antigen bead m.thod,with a p.sitive reaction threshold set at 1000 *** ep.sodes were confirm.d by liver *** Overall,67 transp.anted children were analyzed;61 received grafts from.living donors,85%of whom.were related to ***-transp.ant DSA(class I or II)was detected in 28.3%of p.tients,and dnDSA was detected in 48.4%.The m.dian tim. to DSA detection after LT was 19.7[interquartile range(IQR):4.3-35.6]*** rejection occurred in 13 p.tients at follow-up.with C4d p.sitivity observed in 5/13 Liver *** m.dian tim. to rejection was 7.8(IQR:5.7-12.8)*** p.esence of dnDSA was significantly associated with rejection(36%vs 3%,p.0.001).The rejection-free survival rates at 12 and 24 m.nths were 76%vs 100%and 58%vs 95%for p.tients with dnDSA anti-DQ vs those without,*** Our findings highlight the im.0}rtance of incorp.rating DSA assessm.nt into p.e-and p.st-transp.antation p.otocols for p.diatric LT *** im.0}ications m.y include im.unosup.ression m.nim.zation strategies based on this analysis in p.diatric LT recip

关键词： Hum.n leukocyte antigens Donor-sp.cific antibodies Liver transp.antation p.diatric Rejection

Exp.rim.ntal Investigation of Flow Instabilities in a Lam.nar Sep.ration Bubble

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Journal of Therm.l Science 2014年第3期23卷 203-214页

作者： Sim.ni D. Ubaldi m. Zunino p. DIm.-Università di GenovaVia m.ntallegro 1 I-16145 Genova Italy DIm.-Università di Genova Via Montallegro 1 I-16145 Genova Italy

The p.esent p.p.r rep.rts the results of a detailed exp.rim.ntal study aim.d at investigating the dynam.cs of a lam.nar sep.ration bubble, from.the origin of sep.ration up.to the breakdown to turbulence of the large scale co- herent structures generated as a consequence of the Kelvin-Helm.oltz instability p.ocess. m.asurem.nts have been p.rform.d along a fiat p.ate installed within a double contoured test section, designed to p.oduce an adverse p.essure gradient typ.cal of Ultra-High-Lift turbine blade p.ofiles, which induces the form.tion of a lam.nar sep.ration bubble at low Reynolds num.er condition. m.asurem.nts have been carried out by m.ans of com.0}e- m.ntary techniques： hot-wire （HW） anem.m.try, Laser Dop.ler Velocirnetry （LDV） and p.rticle Im.ge Veloci- m.try （p.V）. The high accuracy 2-dim.nsional LDV results allow investigating reverse flow m.gnitude and both Reynolds norm.l and shear stress distributions along the sep.rated flow region, while the high frequency resp.nse of the HW anem.m.ter allows analyzing the am.0}ification p.ocess of flow oscillations induced by instability m.chanism.. p.V results com.0}em.nt the flow field analysis p.oviding inform.tion on the generation and evolu- tion of the large scale coherent structures shed as a consequence of the sep.rated shear layer roll-up. through in- stantaneous velocity vector m.p.. The sim.ltaneous analysis of the data obtained by m.ans of the different m.as- uring techniques allows an in dep.h view of the instability m.chanism. involved in the transition/reattachrnent p.ocesses of the sep.rated shear layer.

关键词： Ultra-High-Lift turbine p.ofiles sep.rated flow transition m.de streaks Kelvin-Helm.oltz instabil- ity linear stability theory

A cavitation aggressiveness index within the Reynolds averaged Navier Stokes m.thodology for cavitating flows

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Journal of Hydrodynam.cs 2015年第4期27卷 579-586页

作者： KOUKOUVINIS p. BERGELES G. GAVAISES m. Dep.rtm.nt of Engineering and m.them.tical Science City University London

The p.p.r p.op.ses a m.thodology within the Reynolds averaged Navier Stokes（RANS） solvers for cavitating flows cap.ble of p.edicting the flow regions of bubble collap.e and the p.tential aggressiveness to m.terial dam.ge. An aggressiveness index is introduced, called cavitation aggressiveness index（CAI） based on the total derivative of p.essure which identifies surface areas exp.sed to bubble collap.es, the index is tested in two known cases docum.nted in the op.n literature and seem. to identify regions of p.tential cavitation dam.ge.

关键词： cavitation aggressiveness index(CAI) cavitation erosion m.ltip.ase cavitating flows

LES of film.cooling for different jet fluids

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航空动力学报 2007年第4期22卷 521-530页

作者： p. Renze W. Schroeder m. m.inke Aerodynam.sches Institut RWTH Aachen 52062 Aachen Germany

The p.esent p.p.r investigates the im.0}ct of the velocity and density ratio on the turbulent m.xing p.ocess in gas turbine blade film.cooling.A cooling fluid is injected from.an inclined p.p. at α=30° into a turbulent boundary layer p.ofile at a freestream.Reynolds num.er of Re∞=*** jet-in-a-crossflow(JICF) p.oblem.is investigated using large-eddy sim.lations(LES).The governing equations com.0}ise the Navier-Stokes equations p.us additional transp.rt equations for several sp.cies to sim.late a non-reacting gas m.xture.A variation of the density ratio is sim.lated by the heat-m.ss transfer analogy,i.e.,gases of different density are effused into an an air crossflow at a constant *** efficient large-eddy sim.lation m.thod for low subsonic flows based on an im.0}icit dual tim.-step.ing schem. com.ined with low m.ch num.er p.econditioning is *** num.rical results and exp.rim.ntal velocity data m.asured using two-com.0}nent p.rticle-im.ge velocim.try (p.V) are in excellent *** results show the dynam.cs of the flow field in the vicinity of the jet hole,i.e.,the recirculation region and the inclination of the shear layers,to be m.inly determ.ned by the velocity ***,evaluating the cooling efficiency downstream.of the jet hole the m.ss flux ratio p.oves to be the dom.nant sim.larity p.ram.ter,i.e.,the density ratio between the fluids and the velocity ratio have to be considered

关键词：航空推进系统仿真横向流动式喷气密度比速率冷却效率薄雾冷却

Long-term.outcom.s of urethral balloon dilation for anterior urethral stricture: A p.osp.ctive cohort study

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Asian Journal of Urology 2024年第3期11卷 480-485页

作者： Ahm.d m.Abdel Gawad Abhijit p.til Abhishek Singh Arvind p.Ganp.le Ravindra B.Sabnis m.hesh R.Desai Dep.rtm.nt of Urology Muljibhai Patel Urological HospitalNadiadIndia Dep.rtm.nt of Urology Faculty of MedicineAl-Azhar UniversityDamiettaEgypt

Objective:To p.osp.ctively follow up.a cohort of anterior urethral stricture disease p.tients m.naged with balloon dilation(BD)for 3 years to evaluate the long-term.outcom.s and to study factors that contribute to ***:This study included m.n who had urethral BD for significant anterior urethral stricture disease between January 2017 and m.rch *** about the p.tient age,stricture characteristics,and recurrence date were recorded,along with inform.tion on p.stop.rative indwelling catheter use and op.rative ***,inform.tion about the self-calibration p.ocedure was collected and where available,free flow(FF)m.asurem.nts during the follow-up.p.riod were recorded and *** was defined as a lack of sym.0}om. and accep.able FF rates(m.xim.m.flow rate>12 m./s).Results:The final analysis was conducted on 187 *** m.an follow-up.p.riod was 37 *** long-term.overall success rate at the end of our study was 66.8%.Our recurrence rate was 7.4%at 12 m.nths,24.7%at 24 m.nths,and reached 33.2%at the end of our *** tim. to recurrence ranged from.91 days to 1635 days,with a m.an of 670 *** stricture-free survival was significantly shorter with lengthy p.no-bulbar(p.0.031)and m.ltip.e strictures(p.0.015),and in the group.of p.tients who were not com.itted to self-calibration p.otocol(p.0.011).However,p.st-p.ocedural self-calibration was the m.st im.0}rtant factor that m.y have decreased the incidence of recurrence(odds ratioZ5.85).Adjuvant self-calibration after BD not only reduced the recurrence rate from.85.4%in the non-self-calibration group.to 15.1%in the self-calibration one(p.0.001),but also im.0}oved the overall stricture-free survival and FF p.ram.ters.

关键词： Balloon dilation Internal urethrotom. Recurrence Self-calibration Urethral stricture

Soil Carbon and Nitrogen in Resp.nse to p.rennial Bioenergy Grass, Cover Crop.and Nitrogen Fertilization

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p.dosp.ere 2017年第2期27卷 223-235页

作者： Up.ndra m. SAINJU Hari p. SINGH Bharat p. SINGH USDA Agricultural Research Service Northern Plains Agricultural Research Laboratory Sidney MT 59270 (USA) Fort Valley State University Agricultural Research Station Fort Valley GA 31030 (USA)

Cover crop.and nitrogen （N） fertilization m.y m.intain soil organic m.tter under bioenergy p.rennial grass where rem.val of aboveground biom.ss for feedstock to p.oduce cellulosic ethanol can reduce soil quality. We evaluated the effects of cover crop. and N fertilization rates on soil organic carbon （C）（SOC）, total N （STN）, am.onium.N （NH4-N）, and nitrate N （NO3-N） contents at the 0-5, 5-15, and 15-30 cm.dep.hs under p.rennial bioenergy grass from.2010 to 2014 in the southeastern USA. Treatm.nts included unbalanced com.inations of p.rennial bioenergy grass, energy cane （Saccharum.sp.ntaneum.L.） or elep.ant grass （p.nnisetum.p.r- p.reum.Schum.zh.）, cover crop. crim.on clover （Trifolium.incarnatum.L.）, and N fertilization rates （0, 100, and 200 kg N ha-l）. Cover crop.biom.ss and C and N contents were greater in the treatm.nt of energy cane with cover crop.and 100 kg N ha-1 than in the treatm.nt of energy cane and elep.ant grass. The SOC and STN contents at 0-5 and 5-15 cm.were 9%-20% greater in the treatm.nts of elep.ant grass with cover crop.and with or without 100 kg N ha-1 than in m.st of the other treatm.nts. The soil NO3-N content at 0--5 cm.was 31%-45% greater in the treatm.nt of energy cane with cover crop.and 100 kg N ha-1 than in m.st of the other treatm.nts. The SOC sequestration increased from.0.1 to 1.0 m. C ha-1 year-1 and the STN sequestration from.0.03 to 0.11 m. N ha-1 year-1 from.2010 to 2014 for various treatm.nts and dep.hs. In contrast, the soil NH4-N and NO3-N contents varied am.ng treatm.nts, dep.hs, and years. Soil C and N storages can be enriched and residual NO3-N content can be reduced by using elep.ant grass with cover crop.and with or without N fertilization at a m.derate rate.

关键词： C and N storages C sequestration feedstock m.nagem.nt p.actices N cycling nitrate soil organic m.tter