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A grai.-si.e correcti.n for metal polluti.n i.dexes i. ri.er sedi.ents

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i.ternati.nal Journal of Sedi.ent Research 2021年第3期36卷 362-372页

作者： Thomas Vi.cent Gloaguen Paula Núbia Soares Dalto Motta Caroli.a Fonseca Couto Federal Uni.ersi.y of Reconcavo of Bahi. Federal Uni.ersi.y of Mi.as Gerai.

Accordi.g to the Li.t of Hazardous Substances of the Agency of the Toxi. Substances and Di.ease Regi.try(ATSDR 2017), some metalli. elements such as Pb or Cd are sti.l consi.ered as the most polluti.g elements i. the world. These elements accumulate i. sedi.ents, and there are vari.us methods avai.able that di.ferenti.te li.hogeni. sources from anthropogeni. sources. For that, the natural geochemi.al background i. requi.ed, however, i.s defi.i.i.n i. far from unani.ous: i. can be a global or local value,si.gle or stati.ti.ally esti.ated value, dependi.g on the studi.s. our study i. focused on the Subae Ri.er i. the state of Bahi., Northeastern Brazi., whi.h was hi.tori.ally contami.ated by lead metallurgy. The ri.er sedi.ents were sampled at 21 locati.ns: one at the di.charge poi.t of the plant’s rai.water basi.,ten upstream, and ten downstream. The total contents of Fe, Ti. Mn, Pb, Zn, Cu, Cr, parti.le-si.e di.tri.uti.n, and organi. matter were analyzed. The conventi.nal geochemi.al i.dexes, i.e., the polluti.n degree(m Cd), polluti.n load i.dex, and enri.hment factor i.di.ated contami.ati.n by Zn, Pb, Cr, and ***, a new enri.hment factor i. i.troduced, assumi.g that the sedi.ents come from erosi.n of soi.s i. the watershed. After obtai.i.g the natural concentrati.ns of metals i. the clay, si.t, and sand fracti.ns of uncontami.ated reference soi.s, we corrected the polluti.n i.dexes by calculati.g a new i.di.i.ual background i. each sedi.ent sample, accordi.g to i.s grai. si.e di.tri.uti.n. Thi. new approach provi.ed more preci.e i.dexes i. the assessment of sedi.ent polluti.n, by hi.hli.hti.g hi.her contami.ati.n of Zn and Pb(around 50%) and at the same ti.e the absence of Cr and Cu contami.ati.n, two metals not i.volved wi.h the metallurgi.al acti.i.y.

关键词： Enri.hment factor Esti.ated background Parti.le-si.e di.tri.uti.n

Compari.on of the standard Euler-Euler and hybri. Euler-Lagrange approaches for modeli.g parti.le transport i. a pi.ot-scale ci.culati.g flui.i.ed bed

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Parti.uology 2014年第4期12卷 129-137页

作者： Wojci.ch P.Adamczyk Adam Kli.anek Ryszard A.biaecki.Gabri.l Wecel Pawe Kozolub Tomasz Czaki.rt i.sti.ute of Thermal Technology Silesian University of Technology44-100 GliwiceKonarskiego 22Poland i.sti.ute of Advanced Energy Technologi.s Czestochowa University of TechnologyCzestochowaPoland

Parti.le transport phenomena i. small-scale ci.culati.g fi.i.i.ed beds （CFB） can be si.ulated usi.g the Euler-Euler, di.crete element method, and Euler-Lagrange approaches. i. thi. work, a hybri. Euler-Lagrange model known as the dense di.crete phase model （DDPM）, whi.h has common roots wi.h the multi.hase parti.le-i.-cell model, was appli.d i. si.ulati.g parti.le transport wi.hi. a mi.-si.ed experi.ental CFB faci.i.y. i.plementati.n of the DDPM i.to the commerci.l ANSYS Fluent CFD package i. relati.ely young i. compari.on wi.h the granular Euleri.n model. For that reason, vali.ati.n of the DDPM approach agai.st experi.ental data i. sti.l requi.ed and i. addressed i. thi. paper. Addi.i.nal di.fi.ulti.s encountered i. modeli.g flui.i.ati.n processes are connected wi.h long calculati.n ti.es. To reduce ti.es, the complete boi.er models are si.pli.i.d to i.clude just the combusti.n chamber. Such si.pli.i.ati.ns i.troduce errors i. the predi.ted soli. di.tri.uti.n i. the boi.er. To i.vesti.ate the conse- quences of model reducti.n, si.ulati.ns were made usi.g the si.pli.i.d and complete pi.ot geometri.s and compared wi.h experi.ental data. All si.ulati.ns were performed usi.g the ANSYSFLUENT 14.0 package. A set of user defi.ed functi.ns were used i. the hybri. DDPM and Euler-Euler approaches to reci.culate soli. parti.les.

关键词： Parti.le Multi.hase flow CFD Parti.ulate processes CFB Flui.i.ed bed

Fabri.ati.n and comprehensi.e evaluati.n of Zr-based bulk metalli. glass matri. composi.es for bi.medi.al appli.ati.ns

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Sci.nce Chi.a Materi.ls 2024年第12期67卷 4087-4100页

作者： Mari.sz Hasi.k Beata Sobi.szczańska AmadeuszŁaszcz Mi.hałbiały Jacek Chęcmanowski.Tomasz Zatoński Department of Mechani.s Materials and Biomedical EngineeringWrocław University of Science and TechnologyWrocław 50-370Poland Department of Mi.robi.logy Wrocław Medical UniversityWrocław 50-368Poland Department of Advanced Materi.ls Technologi.s Wrocław University of Science and TechnologyWrocław 50-370Poland Cli.i.al Department of otolaryngology Head and Neck SurgeryWrocław Medical UniversityWrocław 50-556Poland

The ai. of thi. study i. to fabri.ate Zr-based bulk metalli. glass matri. composi.es(BMG-MCs)for bi.medi.al usage and subject them to a comprehensi.e and farreachi.g analysi. wi.h respect to thei. mechani.al properti.s,bi.corrosi.n resi.tance,bi.compati.i.i.y,and i.teracti.ns wi.h bi.fi.ms that all may ari.e from thei. chemi.al composi.i.ns and unusual di.ordered i.ternal *** thi. study,we fabri.ate Zr_(40)Ti.(15)Cu_(10)Ni.(10)Be_(25),Zr_(50)Ti.(15)Cu_(10)Ni.(10)Be_(25),and Zr40Ti.5Cu10Ni.Si.Be25 alloys and confi.m thei. glassy matri. nature through di.ferenti.l scanni.g calori.etry(DSC)and scanni.g electron mi.roscopy(SEM)*** mechani.al properti.s,assessed vi. nanoi.dentati.n,demonstrate the hi.h hardness,strength,and elasti.i.y of the produced *** resi.tance i. i.vesti.ated i. si.ulated body flui.,wi.h Zr-based BMG-MCs exhi.i.i.g superi.r performance compared to conventi.nal bi.medi.al materi.ls,i.cludi.g 316L stai.less steel and Ti.Al4V *** i. assessed usi.g human fetal osteoblasti. cell li.e hFoB 1.19,reveali.g low levels of *** study also exami.es the potenti.l for bi.fi.m formati.n,a cri.i.al factor i. the success of bi.medi.al i.plantati.n,where bacteri.l i.fecti.n i. a major *** fi.di.gs suggest,as never reported before,that Zr-based BMG-MCs,wi.h thei. uni.ue composi.e glassy structure and excellent physi.ochemi.al properti.s,are promi.i.g candi.ates for vari.us bi.medi.al appli.ati.ns,potenti.lly offeri.g i.proved performance over tradi.i.nal metalli. bi.materi.ls.

关键词： metalli. glasses composi.es bi.materi.ls mechani.al property cytotoxi.i.y

Ci.ri.e Wagtai. mi.rati.n on the i.do-European flyway:a fi.st geolocator track reveals alternati.e mi.rati.n route and endurance fli.hts to cross ecologi.al barri.rs

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Avi.n Research 2021年第4期12卷 503-508页

作者： Mi.hal Korni.uk Pawel białomyzy Grzegorz Grygoruk Tomasz Tumi.l Pi.trŚwi.tochowski.Marci. Wereszczuk Museum and i.sti.ute of Zoology Polish Academy of SciencesWilcza 6400-679 WarsawPoland Nature Associ.ti.n Dubelt Juszkowy Gród 1716-050 MichałowoPoland

Most long-di.tance mi.rati.g passeri.es that breed i. Europe spend thei. wi.ters i. Afri.a,wi.h only a few speci.s mi.rati.g eastward to spend the non-breedi.g peri.d i. South *** use of the i.do-European flyway i. rare and has been poorly studi.d so ***,i. i. extremely i.teresti.g as wi.hi. that system we are currently wi.nessi.g a recent range expansi.n of European breedi.g long di.tance mi.rants and thus the lengtheni.g of mi.rati.n *** may therefore conceal a uni.ue mi.ratory strategi.s and behavi.ur that can help us to understand the underlyi.g factors and mechani.ms determi.i.g the evoluti.n of mi.rati.n routes,strategi.s and breedi.g range *** on li.ht-level geolocator we reveal a fi.st track of the Ci.ri.e Wagtai.(Motaci.la ci.reola)mi.rati.n,provi.i.g i.si.ht i.to the mi.rati.n pattern,ti.i.g and behavi.ur of the speci.s that recently has extended i.s mi.rati.n ***,the studi.d i.di.i.ual di. not retrace a recent range expansi.n that runs north and east from the Caspi.n Sea but followed a mi.rati.n route runni.g south form the Caspi.n sea,suggesti.g possi.le presence of an alternati.e speci.s range *** overall mi.rati.n di.tance between the breedi.g si.e i. Poland and the non-breedi.g si.e i. Paki.tan was about 10,420 km and i.cluded two endurance movement phases(920 and 2240 km)coveri.g 30%of the whole journey length,wi.h an average movement speed of 574 km/*** explai. thi. mi.rati.n behavi.ur as an adaptati.n for crossi.g the ecologi.al barri.rs i.posed by ari. envi.onments.

关键词： South Asi. Motaci.la ci.reola Flyways Geolocati.n i.di. Long-di.tance mi.rati.n Mi.rati.n route

Vegetati.n structure and edaphi. factors i. veredas reflect di.ferent conservati.n status i. these threatened areas

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Forest Ecosystems 2022年第3期9卷 387-395页

作者： Yule Roberta Ferrei.a Nunes Cami.a Si.vei.a Souza i.lai.e Franci.lly Pi.hei.o de Azevedo odi.lei.Si.ôes de oli.ei.a Lei.i.an Almei.a Frazão Rúbia Santos Fonseca Rubens Manoel dos Santos Walter Vi.na Neves Programa de Pós-Graduaçao Em Botâni.a Apli.ada Departamento de Biologia GeralUniversidade Estadual de Montes ClarosAvenida Dr.Ruy BragaS/N-Bairro Vila MauricéiaMontes ClarosMinas Gerais39401-089Brazil Laboratóri. de Ecologi. Vegetal Universidade Estadual de Montes ClarosAvenida Dr.Ruy BragaS/N-Bairro Vila MauricéiaMontes ClarosMinas Gerais39401-089Brazil i.sti.uto de Ci.nci.s Agrari.s-Uni.ersi.ade Federal de Mi.as Gerai. Avenida Universitária1.000-Bairro Universit�arioMontes ClarosMinas Gerais39404-547Brazil Departamento de Ci.nci.s Florestai. Universidade Federal de LavrasCP 3037LavrasMinas Gerais37200-000Brazil i.sti.uto Mi.ei.o de Gestao dasÁguas Secretaria de Estado de Meio Ambiente e Desenvolvimento SustentávelAvenida JoséCorreia Machado900-Bairro IbiturunaMontes ClarosMinas Gerais39401-832Brazil

Background:i. Cerrado humi. areas,veredas are consi.ered as hygrophi.ous communi.i.s,marked by the presence of the Mauri.i. flexuosa palm tree emergi.g i. the wetter *** i. veredas ecosystems due to drought and changes i. the water table,whi.h represent i.portant areas for bi.di.ersi.y mai.tenance i. the Brazi.i.n cerrado,can lead to the emergence of new landscapes and *** that the veredas are changed i. speci.s composi.i.n due to anthropogeni. factors,i. thi. study,we evaluated the flora composi.i.n and descri.ed the current vegetati.n profi.e of two veredas under di.ferent di.turbances levels that are located i. the north of Mi.as Gerai. State,***:Altogether,2,268 i.di.i.uals of 91 speci.s belongi.g to 36 fami.i.s were *** results demonstrated that the studi.d veredas were flori.ti.ally di.ferent i. terms of the arboreous-shrubby speci.s composi.i.n,ri.hness,and *** the hygrophi.ous forest formati.ns and open areas i. the two veredas present typi.al speci.s from these envi.onments(same speci.s wi.h hi.h i.portance values),the drought i. the water table caused an expansi.n of Cerrado speci.s i. the open areas and i. the hygrophi.ous ***,i. the hygrophi.ous forest there was an i.crease i. the abundance of speci.s that occur i. less saturated ***:our results demonstrate that the studi.d veredas are changi.g i. speci.s composi.i.n due to anthropogeni. factors whi.h leads to the drought of these formati.ns(water balance effect).These anthropogeni. effects cause a modi.i.ati.n wi.h the expansi.n and i.crease i. the abundance of typi.al speci.s of other areas of Cerrado and resi.tant to less saturated soi.s,leadi.g to the veredas ***,future studi.s should i.vesti.ate other veredas on a broader scale to detect changes i. the water table that lead to a consequent change i. vegetati.n *** thi. way,we wi.l have support for the consci.nti.us management and conservati.

关键词： Cerrado Conservati.n Palm swamp Plant di.tri.uti.n Cli.ate change Water balance effect Vereda drought Phytosoci.logi.al analysi.

Endoscopi. submucosal di.secti.n for the treatment of neoplasti. lesi.ns i. the gastroi.testi.al tract

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World Journal of Gastroenterology 2013年第12期19卷 1953-1961页

作者： Andrzej biaek Anna Wi.chowska-Kozowska Jan Pertki.wi.z Katarzyna Karpi.ska Wojci.ch Marli.z Pi.tr Mi.ki.wi.z Teresa Starzyńska Gastroenterology Department Pomeranian Medical University Department of Endoscopy Ministry of Internal Affairs Hospital Endotherapy Ltd Cell Pathology Department Pomeranian Medical University Li.er Uni. Pomeranian Medical University

Ai.: To i.vesti.ate the i.di.ati.ns, resecti.n rate, and safety of endoscopi. submucosal di.secti.n (ESD) for neoplasti. lesi.ns i. the gastroi.testi.al tract at a European referral center. METHoDS: We carri.d out a retrospecti.e analysi. of the ESD procedures performed i. our center for mucosal neoplasti. and submucosal lesi.ns of the gastroi.testi.al tract. The durati.n of the procedure, en bloc and complete (R0) resecti.n rates, and compli.ati.n rates were evaluated. Vari.bles were reported as mean ± SD or si.ple proporti.ns. Uni.ari.te analysi. and compari.ons of procedure ti.es and resecti.n rates were performed usi.g Mann-Whi.ney U tests, or χ2 tests for di.hotomous ***: Between 2007 and 2011, ESD was performed i. a total of 103 pati.nts (46.7% male, mean age 64.0 ± 12.7 years). The i.di.ati.ns for the procedure were epi.heli.l tumor (n = 54), submucosal tumor (n = 42), or other (n = 7). The total en bloc resecti.n rate was 90.3% (93/103) and R0 resecti.n rate 80.6% (83/103). The medi.n speed of the procedure was 15.0 mi./cm2 . The complete resecti.n rate was lower for submucosal tumors ari.i.g from the muscle layer (68%, 15/22, P i.n speed was qui.ker for submucosal tumors locali.ed i. the submucosal layer than for lesi.ns ari.i.g from the musculari. propri. layer (8.1 mi./cm 2 vs 17.9 mi./cm 2 , P i.n rate and speed were better i. the last 24 mo (90.1%, 49/54 and 15.3 mi./cm 2 ) compared to the fi.st 3 years of treatment (73.5%, 36/49, P i./cm2 , P ompli.ati.ns occurred i. 14.6% (n = 15) of pati.nts, i.cludi.g perforati.n i. 5.8% (n = 6), pneumoperi.oneum i. 3.9% (n = 4), delayed bleedi.g i. 1.9% (n = 2), and other i. 2.9% (n = 3). only one pati.nt wi.h delayed perforati.n requi.ed surgi.al treatment. Duri.g the mean follow-up of 26 ± 15.3 mo, among pati.nts wi.h R0 resecti.n, recurrence occurred i. one pati.nt (1.2%).CoNCLUSi.N: ESD i. an effecti.e and safe method for resecti.n of

关键词： Endoscopi. submucosal di.secti.n Gastroi.testi.al neoplasms Gastroi.testi.al stromal tumors Treatment

A numeri.al study of the South Chi.a Sea Warm Current duri.g wi.ter monsoon relaxati.n

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Journal of oceanology and Li.nology 2018年第2期36卷 216-229页

作者： ZHANG Cong Di.G Yang BAo Xi.nwen Bi.Congcong Li.Rui.i.ng ZHANG Cunji. SHEN bia WAN Kai College of oceani. andAtmospheri. Sci.nces Ocean University of China Qingdao 266100 China Key Laboratory of Physi.al oceanography Ministry of Education Ocean University of China Qingdao 266100 China South Chi.a Sea Mari.e Survey and Technology Center State Ocean Administration Guangzhou 510310 China Bei.ai.offshore Engi.eeri.g Survey i.sti.ute State Oceanic Administration Qingdao 266061 China

Usi.g a Fi.i.e-Volume Communi.y ocean Model, we i.vesti.ated the dynami. mechani.m of the South Chi.a Sea Warm Current(SCSWC) i. the northern South Chi.a Sea(NSCS) duri.g wi.ter monsoon relaxati.n. The model reproduces the mean surface ci.culati.n of the NSCS duri.g wi.ter, whi.e model-si.ulated subti.al currents generally capture i.s current pattern. The model shows that the current over the conti.ental shelf i. generally southwestward, under a strong wi.ter monsoon condi.i.n, but a northeastward counter-wi.d current usually develops between 50-and 100-m i.obaths, when the monsoon relaxes. Model experi.ents, focusi.g on the wi.d relaxati.n process, show that sea level i. elevated i. the northwestern South Chi.a Sea(SCS), related to the persi.tent northeasterly monsoon. Followi.g wi.d relaxati.n, a hi.h sea level band bui.ds up along the mi.-shelf, and a northeastward current develops, havi.g an obvi.us verti.al barotropi. structure. Momentum balance analysi. i.di.ates that an along-shelf pressure gradi.nt provi.es the i.i.i.l dri.i.g force for the SCSWC duri.g the fi.st few days followi.g wi.d relaxati.n. The SCSWC subsequently reaches a steady quasi.geostrophi. balance i. the cross-shelf di.ecti.n, mai.ly li.ked to sea level adjustment over the shelf. Lagrangi.n parti.le tracki.g experi.ents show that both the southwestward coastal current and slope current contri.ute to the northeastward movement of the SCSWC duri.g wi.ter monsoon relaxati.n.

关键词： northern South Chi.a Sea South Chi.a Sea Warm Current monsoon relaxati.n numeri.al model pressure gradi.nt barotropi. structure

Value of subjecti.e performance evaluati.n： A theoreti.al perspecti.e

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Journal of Modern Accounti.g and Audi.i.g 2007年第4期3卷 46-52页

作者： ZHAo Xi.o-dong YU Zeng-bia School of Economi.s and Management Tsinghua University Beijing 100084 China Chi.a Central Radi. and TV Uni.ersi.y Beijing 100031 China

To break through the academi. research tradi.i.n of i.olati.g subjecti.e performance evaluati.n （SPE） wi.h objecti.e evaluati.n, and enhance the appli.ati.n and explanati.n power of analyti.al research fi.di.gs, thi. paper adopts a one-peri.d pri.ci.al-agent model, and solves programmi.g problems by i.ternali.i.g vali.i.y condi.i.ns for SPE as constrai.ts accordi.g to revelati.n pri.ci.le. We fi.d that both SPE and i.s objecti.i.ati.n can achi.ve Pareto i.provement for both the pri.ci.al and the agent. our fi.di.gs have a general appli.ati.n beyond bonus contracts; i. not only explai.s the pervasi.e exi.tence of SPE, but also helps to i.terpret phenomena of the objecti.i.ati.n of SPE.

关键词： subjecti.i.y performance evaluati.n pri.ci.al-agent model manageri.l accounti.g

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白钨矿晶体结构及微量元素替代机理

地质学报 2023年第10期97卷 3314-3325页

作者：吴锟言刘飚中南大学有色金属成矿预测与地质环境监测教育部重点实验室湖南长沙410083 中南大学地球科学与信息物理学院湖南长沙410083

白钨矿是钨矿床中主要的载钨矿物,其独特的晶体结构使其富含微量元素,被广泛用于示踪钨成矿过程与流体源区。本文对南岭地区氧化型矽卡岩、还原型矽卡岩、黑钨矿-石英脉型、白钨矿-石英脉型、(矽卡岩-)云英岩型、(石英脉-)云英岩型钨矿... 详细信息

白钨矿是钨矿床中主要的载钨矿物,其独特的晶体结构使其富含微量元素,被广泛用于示踪钨成矿过程与流体源区。本文对南岭地区氧化型矽卡岩、还原型矽卡岩、黑钨矿-石英脉型、白钨矿-石英脉型、(矽卡岩-)云英岩型、(石英脉-)云英岩型钨矿床中白钨矿开展矿物组合和X-射线单晶衍射分析,实验结果显示:(1)白钨矿晶体结构存在一定差异,矽卡岩型钨矿中白钨矿Ca-o键长变化较大(0.0043 nm),石英脉型钨矿中白钨矿次之(0.0035 nm),云英岩型钨矿中白钨矿最小(0.0034 nm);(2)Ca-o键长的差异对最优替代稀土元素影响较大,氧化型矽卡岩钨矿中白钨矿从成矿早期到晚期,最优替代稀土元素从Pr-Nd(进变质阶段)、Pr-Sm(退变质阶段)转变为Nd-Sm(石英-方解石-萤石阶段),而(石英脉-)云英岩型钨矿中白钨矿呈现以Sm^(3+)为中心(Nd-Gd)的最优替代元素;(3)矽卡岩型和云英岩型钨矿中白钨矿,稀土元素主要通过Nb^(5+)耦合替代和空位替代进入白钨矿晶格,石英脉型钨矿的白钨矿中,稀土元素主要通过空位替代和Na+耦合替代进入白钨矿晶格。此外,岩浆流体中稀土特征、共生矿物沉淀、氧化还原环境、外来流体加入、水岩交代作用等对白钨矿中微量元素替代与稀土元素配分型式也具有较大影响。综合分析认为,矽卡岩型钨矿中白钨矿稀土元素配分型式主要受石榴子石等共生矿物沉淀控制,(矽卡岩-)云英岩型钨矿中白钨矿主要继承了岩浆流体的稀土元素配分型式,(石英脉-)云英岩型钨矿中白钨矿稀土元素配分型式主要受晶体结构影响,石英脉型钨矿中白钨矿经历了多阶段流体演化,稀土元素配分型式显示凸起—平坦—凹陷的变化。

关键词：白钨矿晶体结构稀土元素替代机理南岭成矿带