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Luminescence properties of Gd2Si2O7：Ce and Gd2Si2O7：La,Ce under vacuum ultraviolet irradiation

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Journal of Rare Earths 2016年第8期34卷 782-785页

作者： M.Koshimizu t.yanagida Y.Fujimoto K.Asai Department of Applied Chemistry Graduate School of Engineering Tohoku University 6-6-07 Aoba Aramaof Aoba-ku Sendai 980-8579 Japan Graduate School of Materials Science Nara Institute of Science and Technology 8916-5 Takayama-Cho Ikoma Nara 630-0192 Japan

the luminescence properties of Ce- or Ce and La-doped gadolinium pyrosilicate （Gd2Si2Ot, GPS） were characterized using vacuum ultraviolet （VUV） excitation light. A prominent emission band was observed in the luminescence spectra with excitation at 60 nm and ascribed to 5d-4f transition of Ce3＋. Because the excitation wavelength of 60 nm corresponded to the excitation in the host matrix, this result indicated that the excitation energy transfer occurred from the host matrix to Ce3＋ ions. On the basis of the rise in the luminescence time profiles with excitation at 60 nm, the energy transfer occurred within 2 ns, which was much shorter than that of Ce-doped Gd2SiO2. For Ce-doped GPS, the decay rate was slower for the host excitation than that for direct excitation of Ce3＋. In contrast, for Ce and La-doped GPS, no significant difference was observed for the host excitation and direct excitation of Ce3＋. this result indicated that the energy transfer from the host to Ce3＋ ions led to a different radiative decay process, and that La doping had an effect on the energy transfer and decay process.

关键词： energy transfer scintillation vacuum ultraviolet rare earths

Electroweak Axion in Light of GRB221009A

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Chinese Physics Letters 2023年第6期40卷 109-110页

作者： Weikang Lin tsutomu t.yanagida South-Western Institute for Astronomy Research Yunnan UniversityKunming 650500China tsung-Dao Lee Institute(tDLI)&School of Physics and Astronomy Shanghai Jiao Tong UniversityShanghai 201210China Kavli IPMU(WPI) The University of TokyoKashiwaChiba 277-8583Japan

Very high energy(VHE)photons may have a higher survival rate than that expected in standard-model physics,as suggested by the recently reported gamma ray burst *** a photon-axion like particle(ALP)oscillation can boost the survival rate of the VHE photons,current works have not been based on concrete particle models,leaving the identity of the corresponding ALP ***,we show that the required ALP scenario is consistent with the electroweak axion with an anomaly free Z_(10)Froggatt–Nielsen symmetry.

关键词： symmetry weak oscillation

Development of novel rare earth doped fluoride and oxide scintillators for two-dimensional imaging

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Journal of Rare Earths 2011年第12期29卷 1178-1182页

作者： A.Yoshikawa t.yanagida Y.Yokota K.Kamada N.Kawaguchi K.Fukuda A.Yamazaki K.Watanabe A.Uritani t.Iguchi G.Boulon M.Nikl Institute for Materials Research Tohoku University New Industry Creation Hatchery Center Tohoku University R&D Center Tokuyama CorporationShibuya 3-ChomeShibuya-ku Nagoya University Furo-choChikusa-ku Physical Chemistry of Luminescent Materials(LPCML) University of Lyon Institute of Physics AS CR

two topics were focused. the first one was about the gamma-ray scintillator, Pr^3＋：Lu3Al5O12 （LuAG）. the second one was about neutron scintillator, Ce^3＋：^6LiCaAlF6 and Eu^2＋：^6LiCaAlF6 （^6LiCAF）. those scintillators have been developed very recently for modem imaging applications in the medical and homeland security fields. In both cases, the rare earth ions are playing the crucial role as emission centers. Pr^3＋ in LuAG provided fast 5d→4f transition providing noticeably shorter decay time than that of Ce^3＋. Among several candidate hosts, LuAG showed the best performance. Bulk crystal growth, basic scintillation properties, two-dimensional gamma-ray imaging and positron emission mammography （PEM） application were demonstrated. Due to the international situation, the homeland security was compromized by illicit traffic of explosives, drugs, nuclear materials, etc. and the ways to its improvement became an important R＆D topic. For this purpose the Ce and Eu doped LiCAF appeared competitive candidates. Especially, when substitution of 3He neutron detectors was considered, the discrimination ability of gamma-ray from alpha-ray was important. Bulk crystal growth, basic scintillation properties and two-dimensional neutron imaging were demonstrated.

关键词： Scintillator gamma-ray detection neutron detection oxide fluoride Ce, Eu rare earth

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大阪精炼厂铜阳极泥的处理

中国有色冶金 1980年第7期22卷 49-54页

作者： t.yanagida 肖林

1970年,日本三菱金属公司大阪精炼厂迠立了一个新的贵金属回收车间。该车间已生产了四年,主要处理直岛冶炼厂和精炼厂的阳极泥,同时也处理小名浜熔炼与糙炼厂的阳极泥。这些阳极泥的特征是硫酸铅的含量高,造成贵金属特别是银的极为频繁... 详细信息

1970年,日本三菱金属公司大阪精炼厂迠立了一个新的贵金属回收车间。该车间已生产了四年,主要处理直岛冶炼厂和精炼厂的阳极泥,同时也处理小名浜熔炼与糙炼厂的阳极泥。这些阳极泥的特征是硫酸铅的含量高,造成贵金属特别是银的极为频繁的循环。因此,利用浮选法从阳极泥中分离硫酸铅方面作了不少努力。试验室和半工业试验经验指出,用浮选法可有效地将硫酸铅排入尾砂中,使大部分阳极泥均可有效地还原。此外,还发现金银含量丰(宀夫)的精矿极易用回转窑处理,这就排除了常规方法的某些步骤。

关键词：阳极泥硫酸铅碾磨车间氧化焙烧硫酸盐灰吹炉冶金工厂精炼厂日本大阪

Energy exchange between charged relativistic fluids in f(t) gravity

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Communications in theoretical Physics 2024年第10期76卷 108-120页

作者： Z Yousaf U A Khokhar Nasser Bin turki t Suzuki Department of Mathematics University of the Punjab Quaid-i-Azam Campus Department of Mathematics College of Science King Saud University Department of Regional Management Faculty of Management Fukushima College

this study focuses on the effects of a polytropic fluid on a charged gravitational source within f(t) gravity, where t is the torsion scalar. We investigate how the electromagnetic field affects the flow of energy in spherically symmetric and static celestial objects that contain relativistic fluids. By using the gravitational decoupling technique, we analyze the effects of polytropic fluid on the dynamics of the gravitational source, accompanied by the matching of the interior geometry with an exterior at the hypersurface Σ. Finally, with the help of the tolman ⅡV solution, we observe the conduct of energy conditions with the existence of charge using f(t)field equations and got the intended outcomes.

关键词： anisotropy complexity energy exchange hydrodynamics self-gravitating systems

Evaluation of periglacial landforms and formation of soil properties on the Mount Honaz,SW türkiye

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Journal of Mountain Science 2024年第9期21卷 3047-3067页

作者： SERİN Soner UNCU Levent DEDE Volkan tÜRKEŞMurat Institute of Social Sciences İstanbul Universityİstanbul 34119Türkiye Department of Geography BilecikŞeyh Edebali UniversityBilecik 11234Türkiye Department of Geography Ardahan UniversityArdahan 75002Türkiye Center for Climate Change and Policy Studies Boğaziçi Universityİstanbul 34342Türkiye

the main aim of this study is to explain periglacial processes on the summits of Mount Honaz(2571 m a.s.l.),define periglacial landforms,and determine the relationships between morphometric features and topographic *** circles,stony earth circles,non sorted steps,and non sorted stripes were identified on the summits of Mount ***'s correlation coefficient(r)and linear regression analyses were performed by taking metric measurements from 125 periglacial landforms to describe their morphometric features(length,width,height)of periglacial landforms and explain the relationships between them and topographic factors(elevation,slope).to explain the relationships between periglacial landforms and soil properties,soil samples from 11 periglacial landforms were taken and *** landforms,which continue to develop on the summits of Mount Honaz today,have been evaluated with present climate *** of soil samples indicates a notable impact of parent material on the genesis of periglacial *** high ratio of organic matter in mud circle and non sorted step landforms and the high lime ratio in stony earth circle landforms prove a strong relationship between the formation mechanisms of landforms and the soil ***,it is consistent with the findings obtained from the analysis that severe periglacial processes and washing and scavenging events are experienced more on the northern slopes.

关键词： Periglacial processes and geomorphology Soil analysis Morphometric analysis Mount Honaz türkiye

Preparation of microparticles and nanoparticles using membrane-assisted dispersion,micromixing,and evaporation processes

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Particuology 2024年第1期84卷 30-44页

作者： Goran t.Vladisavljevic Chemical Engineering Department Loughborough UniversityLoughboroughLeicestershire LE113TUUnited Kingdom

Synthetic microporous membranes are increasingly used for energy-efficient and controlled production of micro-and nanoparticles and micro-and nanoemulsions with tuneable morphology and physico-chemical properties through various micromixing,emulsification,and evaporation *** emul-sification processes,the membrane pores are used for dispersed phase injection and size-controlled generation of droplets and droplet-templated *** micromixing processes,membrane is utilised as a micromixer for mixing two miscible liquids,usually solvent and antisolvent-rich solutions,which leads to the creation of supersaturation and subsequent nanoprecipitation or *** mem-brane evaporation processes,membrane is used to prevent phase dispersion while allowing efficient molecular diffusion of solvent and/or antisolvent vapour through gas-filled *** dispersion processes can be operated continuously by decoupling shear stress on the membrane surface from cross flow using tube insets,flow pulsations,swirling flow,membrane oscillations or membrane *** generation and solidification can be performed continuously in a single pass by connecting membrane module with a downstream *** dispersion processes can be used for pro-duction of nanoparticles such as nanovesicles(liposomes,micelles,ethosomes,and niosomes),nanogels,polymeric,lipid and metallic nanoparticles,and *** main advantages of membrane-assisted particle generation are in low energy consumption,controlled geometry and hydrodynamic conditions at the microscale level,flexible throughput due to modular and scalable design of membrane devices,and a wide choice of available microporous membranes with various wall porosities,wetta-bilities,pore sizes,and pore morphologies to suit different applications.

关键词： Nanoparticles Microparticles Nanoemulsions Microemulsions Microporous membrane Crystallisation Flash nanoprecipitation Emulsification Zero liquid discharge

Late Ordovician Mass Extinction: Earth, fire and ice

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National Science Review 2024年第1期11卷 51-65页

作者： David A.t.Harper Palaeoecosystems Group Department of Earth SciencesDurham University

the Late Ordovician Mass Extinction was the earliest of the ‘big’ five extinction events and the earliest to affect the trajectory of metazoan life. two phases have been identified near the start of the Hirnantian period and in the middle. It was a massive taxonomic extinction, a weak phylogenetic extinction and a relatively benign ecological extinction. A rapid cooling, triggering a major ice age that reduced the temperature of surface waters, prompted a drop in sea level of some 100 m and introduced toxic bottom waters onto the shelves. these symptoms of more fundamental planetary processes have been associated with a range of factors with an underlying driver identified as volcanicity. Volcanic eruptions, and other products, may have extended back in time to at least the Sandbian and early Katian, suggesting the extinctions were more protracted and influential than hitherto documented.

关键词： Ordovician LOME paleoecology palaeobiogeography biotas

Beta-lactam antibiotic resistance among Escherichia coli isolates from patients with urinary tract infections in Vietnam:A systematic review and meta-analysis

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Asian Pacific Journal of tropical Medicine 2024年第6期17卷 243-255,I0001-I0003页

作者： Dat t Nguyen Princess Margaret Cancer Centre University Health NetworkTorontoOntarioCanada

Objective:to investigate the evolving patterns of antimicrobial resistance against beta-lactam antibiotics in Escherichia coli isolates from urinary tract infection patients in Vietnam,covering the period from 2005 to ***:29 Descriptive studies published between 2010 and 2022 in English and Vietnamese were included in the *** on resistance rates to beta-lactam antibiotics,including cephalosporins and carbapenems,were extracted and *** pooled resistance rates were calculated using random-effects *** trends in resistance were assessed using linear regression ***:Among the beta-lactam antibiotics studied,Escherichia coli exhibited varying levels of resistance,with cephalosporins showing higher resistance rates compared to *** pooled resistance rates were 66%for cefotaxime,65%for ceftriaxone,54%for ceftazidime,and 56%for *** contrast,carbapenems demonstrated lower resistance rates,with weighted pooled resistance rates ranging from 3%to 4%for meropenem,ertapenem,and *** rates were also observed for amoxicillin/clavulanate(35%),ticarcillin/clavulanate(26%),and piperacillin/tazobactam(12%).Significant annual increases in resistance were noted for imipenem(0.56%,Pthis study highlights the critical issue of antimicrobial resistance in urinary tract infections in Vietnam and emphasizes the importance of prudent antibiotic use and the regular monitoring of resistance *** insights are useful for guiding healthcare professionals in optimizing treatment strategies and for policymakers in formulating evidence-based clinical guidelines to combat antibiotic resistance effectively.

关键词： Antimicrobial resistance Urinary tract infection Vietnam