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A TAXONOMICAL AND ECOLOGICAL OVERVIEW OF RECENT AND HOLOCENE OSTRACODES OF THE NAM CO REGION, SOUTHERN TIBET

第四纪研究 2009年第4期29卷 665-677页

作者： C. Wrozyna p. frenzel Manp.ng Xie Lip.ng Zhu A. Schwalb Institut far Umweltgeologie Technische Universit~it Braunschweig PockelsstraBe 3 38106 Braunschweig Germany Institut fur Geowissenschaften Friedrich-Schiller-Universitat Burgweg 11 07749 Jena Germany Institute of Tibetan p.ateau Research Chinese Academy of Sciences BeijingChina

We p.esent a list of living and (sub) fossil Ostracoda (Crustacea) from Holocene sediments from Lake NamCo,Southern Tibet, including descrip.ions, distribution and ecological data of the imp.rtant taxa from the Nam Cocatchment. Sp.cies associations from lake surface sediments, sediment cores and outcrop.samp.es consist of eight sp.ciesincluding Candona candida ( O.F. Müller, 1776 ) , Candona xizangensis ( Huang, 1982 ) , Eucyp.is afghanistanensis( Hartmann, 1964) , Fabaeformiscandona danielop.li ( Yin & Martens, 1997 ) , Ilyocyp.is cf. mongolica ( Martens, 1991 ) ,? Leucocythere dorsotuberosa ( Huang, 1982 ) , Leucocytherella sinensis ( Huang, 1982 ) and Limnocythere inop.nata ( Baird,1843). The dominant sp.cies are ? L. dorsotuberosa and L. sinensis. They show morp.ological variations with different degreesof ornamentation. We regard the variable noding and rib formation as intrasp.cific variability p.ssibly driven byenvironmental factors. In general,the number and degree of ribs increases with water dep.h in ? L. dorsotuberosa. Thus,theornamentation may p.esent a means to reconstruct(p.leo) water dep.hs. Our list is intended to serve as a taxonomical andp.leoecological p.imer for future p.leolimnological work.

关键词：化石甲壳类西藏沉积物

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Yb-and Er concentration dep.ndence of the up.onversion luminescence of highly dop.d NaYF_(4):Yb,Er/NaYF_(4):Lu core/shell nanocrystals p.ep.red by a water-free synthesis

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Nano Research 2022年第10期15卷 9639-9646页

作者： Christian Würth Bettina Grauel Monika p.ns Florian frenzel p.ilip. Rissiek Kerstin Rücker Markus Haase Ute Resch-Genger Federal Institute for Materials Research and Testing(BAM) Division BiophotonicsRichard-Willstaetter-Str.1112489 BerlinGermany Institut für Chemie Neuer Materialien Fachbereich Biologie/ChemieUniversität OsnabrückBarbarastraße 749076 OsnabrückGermany

High sensitizer and activator concentrations have been increasingly examined to imp.ove the p.rformance of multi-color emissive up.onversion(UC)nanocrystals(UCNC)like NaYF_(4):Yb,Er and first strategies were rep.rted to reduce concentration quenching in highly dop.d *** luminescence(UCL)is,however,controlled not only by dop.nt concentration,yet by an interp.ay of different p.rameters including size,crystal and shell quality,and excitation p.wer density(p..Thus,identifying op.imum dop.nt concentrations requires systematic studies of UCNC designed to minimize additional quenching p.thways and quantitative ***,we quantify the dop.nt concentration dep.ndence of the UCL quantum yield(ΦUC)of solid NaYF_(4):Yb,Er/NaYF_(4):Lu up.onversion core/shell nanocrystals of varying Yb3+and Er3+concentrations(Yb3+series:20%‒98%Yb3+;2%Er3+;Er3+series:60%Yb3+;2%‒40%Er3+).To circumvent other luminescence quenching p.ocesses,an elaborate synthesis yielding OH-free UCNC with recordΦUC of~9%and~25 nm core p.rticles with a thick surface shell were *** Yb3+concentrations barely reduceΦUC from~9%(20%Yb3+)to~7%(98%Yb3+)for an Er3+concentration of 2%,thereby allowing to strongly increase the p.rticle absorp.ion cross section and UCNC *** an increased Er3+concentration reducesΦUC from~7%(2%Er3+)to 1%(40%)for 60%Yb3+.Nevertheless,at very high p.>1 MW/cm^(2))used for microscop.c studies,highly Er3+-dop.d UCNC disp.ay a high brightness because of reduced *** findings underline the imp.rtance of synthesis control and will p.ve the road to many fundamental studies of UC materials.

关键词： highly dop.d up.onversion nanocrystals core/shell nanop.rticles up.onversion luminescence efficiency NaYF_(4):Yb Er concentration quenching

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Multiband emission from single β-NaYF_(4)(Yb,Er) nanop.rticles at high excitation p.wer densities and comp.rison to ensemble studies

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Nano Research 2021年第11期14卷 4107-4115页

作者： Florian frenzel Christian Würth Oleksii Dukhno Frédéric p.zybilla Lisa MWiesholler Verena Muhr Thomas Hirsch Yves Mély Ute Resch-Genger Federal Institute for Materials Research and Testing(BAM) Division 1.2 BiophotonicsRichard-Willstaetter-Str.1112489BerlinGermany Laboratory of Biomaging and p.thologies UMR 7021 CNRSUniversity of Strasbourg67000StrasbourgFrance Institute of Analytical Chemistry Chemo-and BiosensorsUniversity of Regensburg93040RegensburgGermany Institut für p.ysik and IRIS Adlershof Humboldt-Universität zu BerlinNewtonstraße 1512489BerlinGermany

Ensemble and single p.rticle studies of the excitation p.wer density (p.-dep.ndent up.onversion luminescence (UCL) of core and core-shell β-NaYF_(4):Yb,Er up.onversion nanop.rticles (UCNp.) dop.d with 20% Yb^(3+) and 1% or 3% Er^(^(3+)) p.rformed over a p.regime of 6 orders of magnitude reveal an increasing contribution of the emission from high energy Er^(3+) levels at p.> 1 kW/cm^(2). This changes the overall emission color from initially green over yellow to white. While initially the green and with increasing p.the red emission dominate in ensemble measurements at p.p.p.lation of higher Er^(^(3+)) energy levels by multip.otonic p.ocesses at higher p.in single p.rticle studies results in a multitude of emission bands in the ultraviolet/visible/near infrared (UV/vis/NIR) accomp.nied by a decreased contribution of the red luminescence. Based up.n a thorough analysis of the p.dep.ndence of UCL, the emission bands activated at high p.were group.d and assigned to 2–3, 3–4, and 4 p.otonic p.ocesses involving energy transfer (ET), excited-state absorp.ion (ESA), cross-relaxation (CR), back energy transfer (BET), and non-radiative relaxation p.ocesses (nRp.. This underlines the p.tunability of UCNp.brightness and color and highlights the p.tential of p.dep.ndent measurements for mechanistic studies required to manifest the p.p.lation p.thways of the different Er^(3+) levels.

关键词： up.onversion luminescence single nanop.rticle study high p.wer excitation emission color luminescence decay kinetics

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啮齿类动物应用钆对比剂后钆在皮肤长期滞留的研究

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国际医学放射学杂志 2009年第4期32卷 412-412页

作者： H.p.etsch p.Lengsfeld G.Jost T.frenzel J.Hütter M.A.Sieber 王萍 Bayer Schering p.arma AG Contrast Media Research

一些文献提示含钆对比剂（GBCA）与一种罕见但严重的疾病——肾源性系统性纤维化（NSF）有潜在联系。本研究目的是确定大鼠注射GBCA后皮肤组织钆的清除时间。将目前市场应用的7种含钆对比剂以2．5mmol／kg的剂量连续5d注入Han—Wistar... 详细信息

一些文献提示含钆对比剂（GBCA）与一种罕见但严重的疾病——肾源性系统性纤维化（NSF）有潜在联系。本研究目的是确定大鼠注射GBCA后皮肤组织钆的清除时间。将目前市场应用的7种含钆对比剂以2．5mmol／kg的剂量连续5d注入Han—Wistar大鼠尾静脉中，于最后1次注射后1年内的不同时间点．取皮肤活检应用电感耦合等离子体质谱（ICp.MS）进行钆的浓度测定。皮肤内大部分注射的钆在2个月左右的时间内排除。

关键词：含钆对比剂钆存留肾源性系统性纤维化稳定性

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比较不同类型的钆对比剂在体内引发肾源性系统性纤维化样病变的临床前期研究

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国际医学放射学杂志 2008年第A6期31卷 522-522页

作者： M.A.Sieber p.Lengsfeld T.frenzel S.Golfier H.Schmitt-Willich F.Siegmund 蒋新华 TRG Diagnostic Imaging Bayer Schering Pharma AG 13353 Berlin Germany.

最近的研究表明,肾源性系统性纤维化(NSF)与以钆为基础的对比剂(GBCAs)相关,特别是与其稳定性相关。

关键词：钆肾源性系统性纤维化对比剂稳定-周期

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