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Journal of.Semiconductors 2024年第9期45卷 28-35页

作者： Leonarde N.Rodrigues Wesley f.Inoch Marcos L.f.Gomes Odilon D.D.Couto Jr. bráulio S.Archanjo Sukarno O.f.rreira Physics Department Federal University of ViçosaViçosa36570-900Minas GeraisBrazil Instituto de f.sica Gleb Wataghin Universidade Estadual de CampinasCampinas13083-859São PauloBrazil National Institute of.Metrology Quality and Technology(Inmetro) Materials Metrology Division(DIMAT)Xerém2525-020Rio de JaneiroBrazil

This work shows that despite a lattice mismatch of.almost 20%, CdMnTe/CdTe/CdMnTe heterostructures grown directly on Si(111) have surprisingly good optical emission properties. The investigated structures were grown by molecular beam epitaxy and characterized by scanning transmission electron microscopy, macro-and micro-photoluminescence. Low temperature macro-photoluminescence experiments indicate three emission bands which depend on the CdTe layer thickness and have dif.erent conf.nement characteristics. Temperature measurements reveal that the lower energy emission band (at 1.48 eV)is associated to def.cts and bound exciton states, while the main emission at 1.61 eV has a weak 2D character and the higher energy one at 1.71 eV has a well-def.ned (zero-dimensional, 0D) 0D nature. Micro-photoluminescence measurements show the existence of.sharp and strongly circularly polarized (up to 40%) emission lines which can be related to the presence of.Mn in the heterostructure. This result opens the possibility of.producing photon sources with the typical spin control of.the diluted magnetic semiconductors using the low-cost silicon technology.

关键词： CdMnTe/CdTe/CdMnTe heterostructure CdTe/CdMnTe quantum emitters quantum dot-like emission silicon(111)substrate

Shape-changing particles f.r locally resolved particle geometry in DEM simulations

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Particuology 2024年第6期89卷 185-190页

作者： Enric Illana Klidi Qyteti Maik Scharnowski Maximilian brömmer Siegmar Wirtz Viktor Scherer Institute of.Energy Plant Technology Ruhr-University BochumBochumGermany

Taking into account the complex shape of.particles in discrete element method (DEM) simulations of.large-scale granular systems is computationally demanding due to the time-consuming contact detection algorithms f.r polyhedral particles. In this short communication, a novel approach that locally resolves the particle shapes where needed and uses a simplif.ed representation elsewhere, to accelerate simulations without compromising accuracy, is presented. f.r this purpose, a method employing a smooth transition of.the particle shape representation f.om analytical spheres to shape-resolving polyhedra is introduced in DEM. The f.asibility and correct implementation of.this approach are demonstrated through simulations of.hopper discharge involving spherical and dodecahedral particles f.om a f.at bottom silo or shaf. kiln. The model capabilities, in terms of.accuracy as well as reduction in computational ef.ort, are quantif.ed f.r a moving bed with continuous outf.ow.

关键词： Polyhedron Size change Shape change Locally resolved DEM

Rising utilization of.stable isotopes in tree rings f.r climate change and f.rest ecology

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Journal of.f.restry Research 2024年第1期35卷 103-116页

作者： Ru Huang Chenxi Xu Jussi Grießinger Xiaoyu f.ng Haif.ng Zhu Achim bräuning National Institute of.Natural Hazards Beijing 100085People’s Republic of China Key Laboratory of.Cenozoic Geology and Environment Institute of Geology and GeophysicsChinese Academy of SciencesBeijing 100029People’s Republic of China CAS Center f.r Excellence in Lif. and Paleoenvironment Beijing 100044People’s Republic of China Institute of.Geography Friedrich-Alexander-University of Erlangen-Nuremberg91058 ErlangenGermany State Key Laboratory of.Tibetan Plateau Earth System Environment and Resources(TPESER)Institute of Tibetan Plateau ResearchChinese Academy of SciencesBeijing 100101People’s Republic of China University of.Chinese Academy of.Sciences Beijing 100049People’s Republic of China

Analyses of.stable isotopes(C,O,H)in tree rings are increasingly important cross-disciplinary *** rapid development in this f.eld documented in an increasing number of.publications requires a comprehensive *** study includes a bibliometric analysis-based review to better understand research trends in tree ring stable isotope ***,1475 publications were selected f.om the Web of.Science Core Collection f.r *** f.ndings are that:(1)numbers of.annual publications and citations increased since *** 1974 to 1980,there were around two relevant publications per ***,f.om 2020 to 2022,this rose sharply to 109 publications per ***,average article citations were less than f.ur per year bef.re 1990,but were around f.ur per article per year af.er 2000;(2)the major subjects using tree ring stable isotopes include f.restry,geosciences,and environmental sciences,contributing to 42.5%of.the total during 1974-2023;(3)the top three most productive institutions are the Chinese Academy of.Sciences(423),the Swiss f.deral Institute f.r f.rest,Snow and Landscape Research(227),and the University of.Arizona(204).These achievements result f.om strong collaborations;(4)review papers,f.r example,(Dawson et al.,Annu Rev Ecol Syst 33:507-559,2002)and(McCarroll and Loader,Quat Sci Rev 23:771-801,2004),are among the most cited,with more than 1000 citations;(5)tree ring stable isotope studies mainly f.cus on climatology and ecology,with atmospheric CO_(2) one of.the most popular *** 2010,precipitation and drought have received increasing *** on this analysis,the research stages,key f.ndings,debated issues,limitations and direc-tions f.r f.ture research are *** study serves as an important attempt to understand the progress on the use of.stable isotopes in tree rings,providing scientif.c guid-ance f.r young researchers in this f.eld.

关键词： Tree rings Stable isotopes Web of.Science Bibliometric

Why ecosystem characteristics predicted f.om remotely sensed data are unbiased and biased at the same time-and how this af.ects applications

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f.rest Ecosystems 2024年第1期11卷 24-31页

作者： Goran Ståhl Terje Gobakken Svetlana Saarela Henrik J.Persson Magnus Ekstrom Sean P.Healey Zhiqiang Yang Johan Holmgren Eva Lindberg Kenneth Nystrom Emanuele Papucci Patrik Ulvdal Hans OleØrka Erik Næsset Zhengyang Hou Håkan Olsson Ronald E.McRoberts Department of.f.rest Resource Management Swedish University of Agricultural Sciences90183UmeåSweden f.culty of.Environmental Sciences and Natural Resource Management Norwegian University of Life SciencesÅsNorway USDA f.rest Service Rocky Mountain Research StationOgdenUTUSA The Key Laboratory f.r Silviculture and Conservation of.Ministry of.Education Beijing Forestry UniversityBeijing100083China Department of.f.rest Resources University of MinnesotaSt.PaulMNUSA

Remotely sensed data are f.equently used f.r predicting and mapping ecosystem characteristics,and spatially explicit wall-to-wall inf.rmation is sometimes proposed as the best possible source of.inf.rmation f.r ***,wall-to-wall inf.rmation typically relies on model-based prediction,and several f.atures of.model-based prediction should be understood bef.re extensively relying on this type of.*** such f.ature is that model-based predictors can be considered both unbiased and biased at the same time,which has important implications in several areas of.*** this discussion paper,we f.rst describe the conventional model-unbiasedness paradigm that underpins most prediction techniques using remotely sensed(or other)auxiliary *** this point of.view,model-based predictors are typically ***,we show that f.r specif.c domains,identif.ed based on their true values,the same model-based predictors can be considered biased,and sometimes severely *** suggest distinguishing between conventional model-bias,def.ned in the statistical literature as the dif.erence between the expected value of.a predictor and the expected value of.the quantity being predicted,and design-bias of.model-based estimators,def.ned as the dif.erence between the expected value of.a model-based estimator and the true value of.the quantity being *** show that model-based estimators(or predictors)are typically design-biased,and that there is a trend in the design-bias f.om overestimating small true values to underestimating large true ***,we give examples of.applications where this is important to acknowledge and to potentially make adjustments to correct f.r the design-bias *** argue that relying entirely on conventional model-unbiasedness may lead to mistakes in several areas of.application that use predictions f.om remotely sensed data.

关键词： Bias Model-based inf.rence Design-based inf.rence

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长寿命UHPf.C组合钢桥面板研究综述

交通运输工程学报 2024年第1期24卷 68-84页

作者：段兰袁翊竑王春生 brÜHWILER Eugen 长安大学公路学院陕西西安710064 瑞士洛桑联邦理工学院结构维护与安全实验室沃州洛桑CH-1015

从三方面归纳与剖析了超高性能纤维增强水泥基(UHPf.C)复合材料组合钢桥面板的研究进展,包括强韧性组合层选材、界面传力机制与损伤累积机理、设计方法与工程应用;总结了纤维类型、纤维掺量对UHPf.C轴拉性能和抗弯性能的影响规律,确定... 详细信息

从三方面归纳与剖析了超高性能纤维增强水泥基(UHPf.C)复合材料组合钢桥面板的研究进展,包括强韧性组合层选材、界面传力机制与损伤累积机理、设计方法与工程应用;总结了纤维类型、纤维掺量对UHPf.C轴拉性能和抗弯性能的影响规律,确定了支撑组合钢桥面板结构分析的多种本构模型;对比分析了热连接、冷连接和混合连接组合界面设计方式的技术特点,归纳了胶粘界面、冷连接剪力键界面与混合连接界面的传力机理试验与理论研究成果;总结了基于冷连接设计理念的组合钢桥面板在合理构造、设计方法、规范规程与工程实践等方面的研究成果,并探讨了长寿命组合钢桥面板的创新与发展方向。研究结果表明:单一或混杂纤维的掺入综合提升了UHPf.C的应变强化能力、弯曲变形能力、抗断裂能力、裂缝宽度控制能力和抗疲劳性能,轴拉条件下UHPf.C三线型简化本构模型有力支撑了组合钢桥面板的设计计算,弹塑性损伤本构模型可描述不可逆疲劳损伤累积;验证了冷连接组合界面的增韧效果与可靠性,新型剪力键既可以提高组合效应,也能增韧UHPf.C层,混合连接界面具有降低界面局部应力集中、提高整体界面抗剪刚度、改善界面传力、提升施工效率等综合技术优势,内聚界面本构模型可实现冷连接界面损伤累积反演分析,界面损伤预测结果准确可靠;基于冷连接的UHPf.C组合钢桥面板可以有效提高钢桥面板的局部刚度,相关设计方法可支撑标准的编制与工程实践;应进一步提升UHPf.C的性价比和界面连接的高效性和可靠性,以支撑组合钢桥面板的长寿命、强韧性、轻量化、易维护、低能耗设计与建造。

关键词：桥梁工程长寿命 UHPf.C组合钢桥面板冷连接件组合界面设计准则免蒸养

Localized-states quantum conf.nement induced by roughness in CdMnTe/CdTe heterostructures grown on Si(111) substrates

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Journal of.Semiconductors 2024年第9期 34-42页

作者： Leonarde do Nascimento Rodrigues Wesley f.orio lnoch Marcos L.f.Gomes Odilon D.D.Couto Jr. bráulio S.Archanjo Sukarno Olavo f.rreira Physics Department Federal University of Vi?osa Instituto de f.sica Gleb Wataghin Universidade Estadual de Campinas National Institute of.Metrology Quality and Technology (Inmetro) Materials Metrology Division (DIMAT)

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Stranched Internal Hernia Revealed by Occlusion of.the Large Libra: A Propos of.a Case

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Case Reports in Clinical Medicine 2024年第1期13卷 37-42页

作者： Abdoulaye Kanté Mamady Almami Kéita Idrissa Tounkara Drissa Ouattara bréhima Bengaly Souleymane Sanogo bréhima Togola Drissa Traoré Nouhoum Ongoiba General Surgery Department of.The Kati-Mali Ref.rence Health Center Koulikoro Mali Service of.Surgery “B” of.The CHU Du Point G Faculty of Medicine and Odontostomatology Bamako Mali

The lef. para-duodenal internal hernia, whose origin is generally embryological, is a rare etiology of.intestinal obstruction f.und mainly in young adults. We report here the case of.acute intestinal obstruction by lef. para-duodenal internal hernia in a 36-year-old young man. It was a patient who consulted urgently f.r occlusive syndrome with cessation of.materials and gases. Abdominal percussion noted abdominal tympanism and pre-hepatic dullness was preserved. The f.ow and icicle signs were negative. Palpation did not objectif. hepatosplenomegaly and did not f.nd any organomegaly either. On the other hand, she f.und an epigastric def.nse. The abdominal X-ray without preparation showed water levels that were wider than high, hail-like. We perf.rmed a median above and below umbilical laparotomy and intraoperatively, it was an internal hernia with incarceration of.small loops in a voluminous lef. paraduodenal sac of.12 cm. They were not necrotic and quickly recolored af.er extrication. We resected the hernial sac and closed the hernial orif.ce with separate stitches with absorbable suture 0. The postoperative course was simple. The patient was discharged f.om the hospital on the 4th postoperative day. Af.er 18 months of.hindsight, he is doing well.

关键词： Paraduodenal Internal Hernia Occlusion Laparotomy

Investigating the inf.ow into a granular bed using a locally resolved method

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Particuology 2024年第2期85卷 89-101页

作者： Maximilian brommer Maik Scharnowski Enric Illana Mahiques Siegmar Wirtz Viktor Scherer Ruhr University Bochum Institute of Energy Plant TechnologyUniversitätsstraβe 15044780BochumGermany

Discrete Element Method-Computational f.uid Dynamics(DEM/Cf.)simulations of.industrial-scale granular systems employ spatial averaging(porous media approach)f.r the f.uid-particle interaction in the whole domain,which can lead to poor accuracy,f.r instance at f.ow inlets,as local particle bulk morphology is not *** paper presents an approach where the interstitial f.ow in crucial areas with large gradients can be resolved locally in an otherwise unresolved domain,so that a mixed resolved-unresolved method is *** a generic example to show the f.asibility and perf.rmance of.the new approach,the inf.ow of.ambient air into a f.at-bottom hopper through a narrow orif.ce is *** an experimental setup,the vertical prof.le of.the pressure decay through the inlet and across the packing is chosen f.r com-parison with respective *** obtained with the conventional porous media method and the locally resolved approach are compared to these experiments f.r varying volume f.ow rates and f.r two dif.erent particle *** of.dif.erent size as well as dodecahedrons are *** is f.und that although averaging methods already provide good approximations,the locally resolved method can improve the result especially when conventional drag laws are not applicable due to wall ef.ects or if.large velocity gradients exist.

关键词： DEM/Cf. Packed bed Pressure drop

Benef.ts of.past inventory data as prior inf.rmation f.r the current inventory

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f.rest Ecosystems 2020年第2期7卷 263-273页

作者： Annika Kangas Terje Gobakken Erik Næsset Bioeconomy and Environment Natural Resources Institute Luke(Finland)Yliopistokatu 680100 JoensuuFinland f.culty of.Environmental Sciences and Natural Resource Management Norwegian University of Life SciencesP.O.Box 5003NO-1432ÅsNorway.

Background:When auxiliary inf.rmation in the f.rm of.airborne laser scanning(ALS)is used to assist in estimating the population parameters of.interest,the benef.ts of.prior inf.rmation f.om previous inventories are not *** a simulation study,we compared three dif.erent approaches:1)using only current data,2)using nonupdated old data and current data in a composite estimator and 3)using updated old data and current data with a Kalman *** also tested three dif.erent estimators,namely i)Horwitz-Thompson f.r a case of.no auxiliary inf.rmation,ii)model-assisted estimation and iii)model-based *** compared these methods in terms of.bias,precision and accuracy,as estimators utilizing prior inf.rmation are not guaranteed to be ***:The largest standard errors were obtained when neither prior inf.rmation nor auxiliary inf.rmation were *** a growth model was not applied to update the old data,the resulting composite estimators were *** RMSEs were obtained using non-updated prior inf.rmation in a composite *** the ALS data as auxiliary inf.rmation produced smaller RMSE than using prior inf.rmation f.om the old *** smallest RMSEs were obtained when both the auxiliary data and updated old data were *** growth updating the bias can be substantially reduced,although design-unbiasedness of.the estimator cannot be ***:Prior inf.rmation f.om old inventory data can be usef.l also when combined with highly accurate auxiliary inf.rmation,when both data sources are ef.iciently *** benef.ts obtained f.om using the old data will increase if.the past harvests can be detected without errors f.om changes in the auxiliary data instead of.being predicted with models.

关键词： Data f.sion Kalman f.ltering

Morphological traits explain the individual position within resource-consumer networks of.a Neotropical marsupial

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Current Zoology 2024年第4期70卷 453-464页

作者： Nicholas f.de Camargo Hernani f.M.de Oliveira Juliana f.Ribeiro Amabilio J.A.de Camargo Emerson M.Vieira Laboratorio de Ecologia de Vertebrados Departamento de EcologiaInstituto de Ciencias BiologicasUniversidade de BrasiliaCP 04457BrasiliaDF70910-900Brazil Departamento de Zoologia Setor de Ciencias BiologicasUniversidade Federal do ParanaAvenida Coronel Francisco Heraclito dos Santos100CuritibaPR81531980Brazil Embrapa Cerrados Rodovia BR020km 18CP 08223PlanaltinaDE73310-970Brazil

Knowledge regarding the inf.uence of.individual traits on interaction patterns in nature can help understand the topological role of.individuals within a network of.intrapopulation *** tested hypotheses on the relationships between individuals'positions within networks(specialization and centrality)of.4 populations of.the mouse opossum Gracilinanus agilis and their traits(i.e.,body length,body condition,tail length relative to body length,sex,reproductive condition,and botf.y parasitism)and also seasonal ef.ects in the brazilian *** with lower body length,better body condition,and relatively shorter tail were more specialized(i.e.,less connected within the network).Individuals were also more specialized and less connected during the warm-wet *** relationship between individuals'position in the network and body traits,however,was independent of.*** propose that specialization may arise not only as a result of.pref.rred f.ed-ing strategies by more capable individuals(i.e.,those with better body condition and potentially prone to def.nd and access high-quality f.od resources)but alsobecause of.morphological ***/younger individuals(consequently with less experience in f.raging)and short-tailed individuals(less skilled to explore the vertical strata of.the vegetation)would f.ed only on a subset of.the available f.od resources and consequently become more ***,individuals are more specialized during the warm-wet season because of.high competition(population-dense period)and higher ecological opportunities(resource-rich period).Theref.re,our study reveals the relevance of.individual traits inshaping interactionpatternsandspecialization inpopulations.

关键词： bodytraits centrality Cerrado Gracilinanus agilis seasonality specialization.