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Multiband emission from single β-NaYF_(4)(Yb,Er) nanoparticles at high excitation power densities and comparison 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 Przybilla 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 Pathologies UMR 7021 CNRSUniversity of Strasbourg67000StrasbourgFrance Institute of Analytical Chemistry Chemo-and BiosensorsUniversity of Regensburg93040RegensburgGermany Institut für Physik and IRIS Adlershof Humboldt-Universität zu BerlinNewtonstraße 1512489BerlinGermany

Ensemble and single particle studies of the excitation power density (P)-dependent upconversion luminescence (UCL) of core and core-shell β-NaYF_(4):Yb,Er upconversion nanoparticles (UCNPs) doped with 20% Yb^(3+) and 1% or 3% Er^(^(3+)) performed 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 g population of higher Er^(^(3+)) energy levels by multiphotonic processes at higher P in single particle studies results in a multitude of emission bands in the ultraviolet/visible/near infrared (UV/vis/NIR) accompanied by a decreased contribution of the red luminescence. Based upon a thorough analysis of the P-dependence of UCL, the emission bands activated at high P were grouped and assigned to 2–3, 3–4, and 4 photonic processes involving energy transfer (ET), excited-state absorption (ESA), cross-relaxation (CR), back energy transfer (BET), and non-radiative relaxation processes (nRP). This underlines the P-tunability of UCNP brightness and color and highlights the potential of P-dependent measurements for mechanistic studies required to manifest the population pathways of the different Er^(3+) levels.

关键词： upconversion luminescence single nanoparticle study high power excitation emission color luminescence decay kinetics

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Fabrication of Nb2O5/C nanocomposites as a high performance anode for lithium ion battery

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Chinese Chemical Letters 2017年第4期28卷 755-758页

作者： gan-Ying Zeng Hao Wang Jing guo Li-Mei cha Yu-Hai Dou Jian-Min Ma Schcool of Physics and Electronics Hunan University Changsha 410082 China College of Materials Science and Engineering Hunan University Changsha 410082 China Institute for Superconducting and Electronic Materials Australian Institute for Innovative Materials University of Wollongong Wollongong New South Wales 2500 Australia Science and Technology on Surface Physics and Chemistry Laboratory China Academy of Engineering Physics Mianyang 621908 China

Nb_2O_5/C nanosheets are successfully prepared through a mixing process and followed by heating *** Nb_2O_5/C based electrode exhibits high rate performance and remarkable cycling ability,showing a high and stable specific capacity of ~380mAhg^（-1） at the current density of 50 mAg^（-1）（much higher than the theoretical capacity of Nb_2O_5）.Further more,at a current density of 500mAg^（-1）,the nanocomposites electrode still exhibits a specific capacity of above 150 mAh g^（-1） after 100 *** results suggest the Nb_2O_5/C nanocomposite is a high performance anode material for lithium-ion batteries.

关键词： N2O5 Carbon Composite Anode Lithium-ion battery

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Assessing the spatiotemporal malaria transmission intensity with heterogeneous risk factors:A modeling study in Cambodia

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Infectious Disease Modelling 2023年第1期8卷 253-269页

作者： Mutong Liu Yang Liu ly Po Shang Xia Rekol Huy Xiao-Nong Zhou Jiming Liu Department of Computer Science Hong Kong Baptist UniversityHong Kong Special administrative region of China HKBU-CSD&NIPD Joint Research Laboratory for Intelligent Disease Surveillance and Control China National Center for Parasitology Entomology&Malaria Control(CNM)Ministry of HealthPhnom PenhCambodia National Institute of Parasitic Diseases Chinese Center for Disease Control and PreventionShanghaiChina Key Laboratory of Parasite and Vector Biology National Health and Commission of the People's Republic of ChinaShanghaiChina WHO Collaborating Center for Tropical Diseases ShanghaiChina

Malaria control can significantly benefit from a holistic and precise way of quantitatively measuring the transmission intensity,which needs to incorporate spatiotemporally varying risk *** this study,we conduct a systematic investigation to characterize malaria transmission intensity by taking a spatiotemporal network perspective,where nodes capture the local transmission intensities resulting from dominant vector species,the population density,and land cover,and edges describe the cross-region human mobility *** inferred network enables us to accurately assess the transmission intensity over time and space from available empirical *** study focuses on malaria-severe districts in *** malaria transmission intensities determined using our transmission network reveal both qualitatively and quantitatively their seasonal and geographical characteristics:the risks increase in the rainy season and decrease in the dry season;remote and sparsely populated areas generally show higher transmission intensities than other *** findings suggest that:the human mobility(e.g.,in planting/harvest seasons),environment(e.g.,temperature),and contact risk(coexistences of human and vector occurrence)contribute to malaria transmission in spatiotemporally varying degrees;quantitative relationships between these influential factors and the resulting malaria transmission risk can inform evidence-based tailor-made responses at the right locations and times.

关键词： Malaria Transmission intensity assessment Spatiotemporal network Computational approach Heterogeneous risk factors

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Thank god it's Friday!

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中国周刊 2004年第5期 38-39页

作者： cha Dao

Two weeks ago, Ma Ling asked her friends what was a good place to have chat after work in *** half of them told her that she should try a restaurant called T.g.I. Friday’s, which is on the Third Ring

关键词： Thank god it’s Friday

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Effect of irrigation water containing arsenic on elemental composition of bean and lettuce plants cultivated in calcareous sandy soil

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Food Production, Processing and Nutrition 2019年第1期1卷 1-10页

作者： Sirat Sandil Péter Dobosy Krisztina Kröpfl Anna Füzy MihályÓvári gyula Záray MTA Centre for Ecological Research Danube Research InstituteKarolinaút 29-31Budapest H-1113Hungary Cooperative Research Centre of Environmental Sciences Eötvös Loránd UniversityPázmány Péter sétány 1/ABudapest H-1117Hungary MTA Centre for Agricultural Research Institute for Soil Sciences and Agricultural ChemistrHerman Ottóút 15Budapest H-1022Hungary

Background:The uptake of arsenic by vegetables from soil irrigated with arsenic enriched groundwater poses a major health *** edible portion of these vegetables transfer arsenic to the human *** uptake of arsenic was studied in bean(Phaseolus vulgaris L.)and lettuce(Lactuca sativa L.)in a controlled greenhouse pot culture with calcareous sandy soil as *** plants were irrigated with water containing sodium arsenate at concentrations 0.1,0.25 and 0.5 mg L^(-1).The total arsenic concentration of the different plants parts was determined by ICP-MS,following microwave-assisted acid *** change in plant biomass production and essential macroelements(Mg,P,K)and microelements concentration(Fe,Mn,Cu,Zn)was also ***:The As concentration in the bean was in the order:root>stem>leaf>bean fruit and in lettuce:root>*** the highest dose(0.5 mg L^(-1))the As concentration in the bean fruit and lettuce leaves was 22.1μg kg^(-1)and 1207.5μg kg^(-1)DW,*** As concentration in the irrigation water resulted in decreased edible biomass production in bean,while in lettuce the edible biomass production *** plant exhibited any visible toxicity *** significant change was observed in the macro and microelements *** total and the water-soluble arsenic in soil amounted to 3.5 mg kg^(−1)and 0.023 mg kg^(−1),*** transfer factor was found to increase with increase in the As treatment *** transfer factor range for bean from root to fruit was 0.003–0.005,and for lettuce from root to leaves was 0.14–***:Considering the FAO-WHO recommended maximum tolerable daily intake(MTDI)limit of 2.1μg kg^(-1)body weight,and the biomass production,both plants should not be cultivated at As treatment level higher than 0.1 mg L^(-1).

关键词： Arsenic irrigation water uptake transfer factor calcareous sandy soil vegetables

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Earth observation and geospatial big data management and engagement of stakeholders in Hungary to support the SDgs

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Big Earth Data 2021年第3期5卷 306-351页

作者： Szabolcs Mihály gábor Remetey-Fülöpp Dániel Kristóf Anna Czinkóczky Tamás Palya LászlóPásztor Pál Rudan györgy Szabó LászlóZentai Hungarian Society of Surveying Mapping and Remote Sensing(MFTTT)BudapestHungary Earth Observation Department Lechner Nonprofit LtdBudapestHungary Department of Laboratory of Spatial Analysis and Environment Hungarian University of Agriculture and Life Sciences(MATE)GödöllőHungary gIS Department Lechner Nonprofit Ltd BudapestHungary Department of Soil Mapping and Environmental Institute for Soil SciencesCentre for Agricultural ResearchBudapestHungary governmental Agency for IT Development BudapestHungary Faculty of Civil Engineering Department of Photogrammetry and GeoinformaticsBudapest University of Technology and EconomicsBudapestHungary ELTE Eötvös Loránd University Institute of Cartography and GeoinformaticsBudapestHungary

To support the monitoring and reporting processes during imple-mentation of the Sustainable Development goals,well-developed,commonly recognized Earth observations and geospatial data,methods,innovations,committed professionals,and strong sus-tainability policies are *** article informs the readers on the Earth observation and geoinformation developments and innovations,and on the engagement of profession,academy and governance to support implementation of the Sustainable Development goals in ***,analyses and critical assessments are given on the elements selected from Hungarian sustainable-oriented Earth observation and geospatial novelties:(a)Working group for Sustainable Development mission and national sustainabilitypolicy,(b)international partnerships,domestic activities and achievements,(c)status of the professional education,(d)spatial databases and services to support implementation of the sustain-able development,(e)a case study on the internationally recog-nized soil geoinformation system,(f)national Earth Observation Information System and perspectives of its applications for mon-itoring the *** article conclusion strongly advises the Hungarian realization of(a)institutionalization of the Earth observation and geospatial tools and capacity for sustainable development,(b)their use in integration with statistical data,(c)establishment of national spatial information infrastructure and(d)development and spreading of the use of big data.

关键词： Earth observation environment gIS soil sustainable development

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Assembly of a parts list ofthe human mitotic cell cycle machinery

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Journal of Molecular Cell Biology 2019年第8期11卷 703-718页

作者： Bruno giott Sz-Hau Chen Mark W.Barnett Tim Regan Tony ly Stefan Wiemann David A.Hume Tom C.Freeman The Roslin Institute University of Edinburgh Easter Bush Midlothian EH25 9RG Scotland UK Biosciences and Biotechnology Institute EDyP Department CEA Grenoble 17 rue des Martyrs 38054 Grenoble France Wellcome Centre for Cell Biology University of Edinburgh Swann Building Edinburgh EH9 3BF Scotland UK Molecular genome Analysis (B050) Deutsches Krebsforschungszentrum Im Neuenheimer Feld 580 69120 Heidelberg Germany Mater Research Institute University of Queensland Level 3 Aubigny Place Raymond Terrace South Brisbane Qld 4101 Australia

The set of proteins required for mitotic division remains poorly characterized. Here, an extensive series of correlation analyses of human and mouse transcriptomics data were performed to identify genes strongly and reproducibly associated with cells undergoing S/g2-M phases of the cell cycle. In so doing, 701 cell cycle-associated genes were defined and while it was shown that many are only expressed during these phases, the expression of others is also driven by alternative promoters. Of this list, 496 genes have known cell cycle functions, whereas 205 were assigned as putative cell cycle genes, 53 of which are functionally uncharacterized. Among these, 27 were screened for subcellular localization revealing many to be nuclear localized and at least three to be novel centrosomal proteins. Furthermore, 10 others inhibited cell proliferation upon siRNA knockdown. This study presents the first comprehensive list of human cell cycle proteins, identifying many new candidate proteins.

关键词： cell cycle systems biology gene expression transcriptome network analysis

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Removal of primary iron rich phase from aluminum-silicon melt by centrifugal separation

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China Foundry 2013年第2期10卷 112-117页

作者： Seong Woo Kim Un Ho Im Hyeong Cheol cha Se Hyeong Kim Ji Eun Jang Ki Young Kim School of Energy Materials and Chemical EngineeringKorea University of Technology and Education

Recycling is a major consideration in continued aluminum use due to the enormous demand for high quality products. Some impurity elements gradually accumulate through the repetitive reuse of aluminum alloy scrap. Of them, the iron content should be suppressed under the allowed limit. In the present research, a novel separation method was introduced to remove primary iron-rich intermetallic compounds by centrifugation during solidification of AI-Si-Fe alloys. This method does not use the density difference between two phases as in other centrifugal methods, but uses the order of solidification in AI-Si-Fe alloys, because iron promotes the formation of intermetallic compounds with other alloying elements as a primary phase. Two AI-Si-Fe alloys which have different iron contents were chosen as the starting materials. The iron-rich phase could be efficiently removed by centrifuging under a centrifugal force of 40 g. Coarse intermetallic compounds were found in the sample inside the crucible, while rather fine intermetallic compounds were found in the sample outside the crucible. Primary intermetallic compounds were linked to each other via aluminum-rich matrix, and formed like a network. The highest iron removal fraction is 67% and the lowest one is 7% for AI-12Si-1.7Fe alloy. And they are 82% and 18% for AI-12Si-3.4Fe alloy, respectively.

关键词： Al-Si alloys iron removal centrifugal separation

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Death of Two Military Pilots in Hawk‑108 Fighter Jet Crash

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Journal of Forensic Science and Medicine 2018年第2期4卷 101-103页

作者： Chng Kay ly Mohd Yusmiaidil Putera Mohd Yusof Ahmad Hafizam Hasmi Mohd Shah Mahmood Department of Forensic Medicine National Institute of Forensic MedicineHospital Kuala LumpurMinistry of Health MalaysiaKuala Lumpur Institute of Pathology Laboratory and Forensic MedicineUniversiti Teknologi MARA Centre of Oral and Maxillofacial Diagnostics and Medicine Studies Faculty of DentistryUniversiti Teknologi MARASelangorMalaysia

Deaths associated with emergency seat ejection are *** is the first case reported in Malaysia since 1980 involving the death of two renowned fighter pilots postejection as safety *** mechanism involves several phases which last for splits of *** phase has its own setback despite serving as a safety *** the pilots’death was as a result of the canopy separation,windblast effect,g‑force effect(gravitational force)as well as acceleration *** speed and high altitude would have further contributed to the death.

关键词： +gz‑induced loss of consciousness air crash ejection mechanism

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Concurrent multi-peak Bragg coherent x-ray diffraction imaging of 3D nanocrystal lattice displacement via global optimization

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npj Computational Materials 2023年第1期9卷 1579-1590页

作者： Siddharth Maddali Travis D.Frazer Nazar Delegan Katherine J.Harmon Sean E.Sullivan Marc Allain Wonsuk cha Alan Dibos Ishwor Poudyal Saugat Kandel Youssef S.g.Nashed F.Joseph Heremans Hoydoo You Yue Cao Stephan O.Hruszkewycz Materials Science Division Argonne National LaboratoryLemontIL 60439USA Center for Molecular Engineering Argonne National LaboratoryLemontIL 60439USA Aix-Marseille Univ CNRSCentrale MarseilleInstitut FresnelMarseilleFrance X-ray Science Division Argonne National LaboratoryLemontIL 60439USA Center for Nanoscale Materials Argonne National LaboratoryLemontIL 60439USA Mathematics&Computer Science Division Argonne National LaboratoryLemontIL 60439USA Pritzker School of Molecular Engineering University of Chicago5640 South Ellis AvenueChicagoIL 60637USA SLAC National Accelerator Laboratory Menlo ParkCAUSA

In this paper we demonstrated a method to reconstruct vector-valued lattice distortion fields within nanoscale crystals by optimization of a forward model of multi-reflection Bragg coherent diffraction imaging(MR-BCDI)*** method flexibly accounts for geometric factors that arise when making BCDI measurements,is amenable to efficient inversion with modern optimization toolkits,and allows for globally constraining a single image reconstruction to multiple Bragg peak *** is enabled by a forward model that emulates the multiple Bragg peaks of a MR-BCDI experiment from a single estimate of the 3D crystal *** present this forward model,we implement it within the stochastic gradient descent optimization framework,and we demonstrate it with simulated and experimental data of nanocrystals with inhomogeneous internal lattice *** find that utilizing a global optimization approach to MR-BCDI affords a reliable path to convergence of data which is otherwise challenging to reconstruct.

关键词： optimization coherent lattice

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