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Effects of varying Alx moles on structure and luminescence properties of ZnAl_(x)O_(1.5x+1):0.1 mol%Tb^(3+)nanophosphors prepared using citrate sol-gel method

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Journal of Rare Earths 2023年第3期41卷 358-364,I0002页

作者： V.M.Maphiri L.T.Melato M.R.Mhlongo T.T.Hlatshwayo T.E.Motaung L.f.Koao S.V.Motloung Department of Physics Sefako Makgatho Health Science UniversityP.O.Box 94Medunsa0204South Africa Department of Mathematics Non Destructive Testing and PhysicsVaal University of TechnologyAndries Potgieter BlvdVanderbijlpark1900South Africa Department of Physics University of PretoriaPretoria0002South Africa Department of Chemistry School of Science in the College of Science Engineering and TechnologyUniversity of South AfricaPreller StreetMuckleneuk RidgeCity of TshwaneP.O Box 392UNISA 0003South Africa Department of Chemistry Sefako Makgatho Health Science UniversityP.O.Box 94Medunsa0204South Africa Department of Physics University of the Free State(Qwaqwa Campus)Private Bag X13Phuthaditjhaba 9866South Africa Department of Chemical and Physical Sciences Walter Sisulu UniversityMthathaSouth Africa

Un-doped and ZnAl_(x)O_(1.5x+1):0.1 mol%Tb^(3+)(ZAOT)nano-powders were synthesized via citrate sol-gel *** AIx moles were varied in the range of 0.25≤x≤*** X-ray powder diffraction(XRD)data reveal that for xf mixed phases of the cubic ZnAl_(2)O_(4) and hexagonal ZnO phases,while for x>1.5 the structure consists of single phase of cubic ZnAl_(2)O_(4).The Raman and fourier-trans form infrared(fTIR)vibrational spectroscopy show the presence of vibrations emanating ZnAl_(2)O_(4) *** electron microscopy(SEM)and transmission electron microscopy(TEM)show the presence of irregular sphere at x>2.0 attributed to ZnAl_(2)O_(4).The photoluminescence(PL)spectroscopy reveals emissions from both the host and Tb^(3+)*** from Tb^(3+)are observed at 382,414,439,458 nm and 489,545,585,621 nm,which were attributed to the^(5)D_(3)→^(7)f_(6,5,4,2) and ^(5^)D_(4)→^(7)f_(6,5,4,3),*** results confirm that the Tb^(3+)occupation site depends on the Alx *** International Commission on Illumination(CIE)colour chromaticity shows that the emission colour can be tuned from blue to green by varying the AIx moles.

关键词： Citrate sol-gel ZnAl_(2)O_(4)/ZnO Tb^(3+)-doped Al_(x)moles Photoluminescence Rare earths

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Early stage risk communication and community engagement(RCCE)strategies and measures against the coronavirus disease 2019(COVID-19)pandemic crisi

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Global Health Journal 2021年第1期5卷 44-50页

作者： Ernest Tambo Ingrid C.Djuikoue Gildas K.Tazemda Michael f.fotsing Xiao-Nong Zhou Higher Institute of Health Sciences University of the MountainsP.O.Box 208 BagangtéCameroon Prevention and Control NGOCameroon National Institute of Parasitic Diseases Chinese Center for Disease Control and Prevention

Coronavirus disease 2019(COVID-19)pandemic has proven to be tenacious and shows that the global commu nity is still poorly prepared to handling such emerging *** global solidarity in emergency preparedness and response,and the mobilization of conscience and cooperation,can serve as an excellent source of ideas and measures in a timely *** article provides an overview of the key components of risk communication and community engagement(RCCE)strategies at the early stages in vulnerable nations and populations,and highlight contextual recommendations for strengthening coordinated and sustainable RCCE preventive and emergency response strategies against COVID-19 *** solidarity calls for firming govemance,abundant community participation and enough trust to boost early pandemic preparedness and *** public RCCE response interventions needs crucially improving government health systems and security proactiveness,community to individual confinement,trust and resilience *** better understand population risk and vulnerability,as well as COVID-19 transmission dynamics,it is important to build intelligent systems for monitoring isolation/quarantine and tracking by use of artificial intelligence and machine learning systems *** and lessons learned from the international community is crucial for emerging pandemics prevention and control programs,especially in promoting evidence-based decision-making,integrating data and models to inform effective and sustainable RCCE strategies,such as local and global safe and effective COVID-19 vaccines and mass immunization programs.

关键词： Coronavirus disease 2019(COVID-19) Risk communication and communityengagement(RCCE) Response Trust Governance Pandemic Vaccination

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Effect of sowing and oversowing on species abundance in mountain pastures of central Italy

Effect of sowing and oversowing on species abundance in moun...

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ⅩⅪ International Grassland Congress and the Ⅷ International Rangeland Congress

作者： A.Pardini f.Natali University of.florence-Piazzale Cascine 18-50144 firenze （I）

＜正＞Introduction Large parts of Central Italy are mountainous and marginal due to climate constraints,shallow soils,steeped slopes and distance from main *** productivity is low nonetheless of the agronomic advances,and farmers increase their incomes by offering tourist ***-tourism is favoured by conservation of biodiversity（Uncini Manganelli et al., 2002）.Under this point of view,farmers seek low input techniques for pasture management that sustain the productivity and at the same time conserve plant diversity（Pardini,2002）.A trial was done to control what is the effect of sowing and oversowing on productivity and abundance of pasture *** research has been fund by ARSIA of the Regional Government of Tuscany.

关键词： agro-tourism biodiversity

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Gauge boson mass generation–without Higgs–in the scalar strong interaction hadron theory

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Natural Science 2010年第4期2卷 398-401页

作者： f. C. Hoh 不详

It is shown that the gauge boson mass is natu-rally generated–without Higgs–in the pion beta decay using the scalar strong interaction had-ron theory. This mass generation is made pos-sible by the presence of relati... 详细信息

关键词： No Higgs Gauge Boson Mass Scalar Strong Interaction

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Energy Aware Spectrum Access in Cognitive Radio Networks with Imperfect Channel Sensing

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China Communications 2012年第9期9卷 127-130页

作者： Wei Yifei Du Chenhui feng Ruijun f. Richard Yu Beijing University of Posts and Telecommunications Beijing 100876 P. R. China China Mobile Communications Corporation Beijing 100032 P.R. China Department of Systems and Computer Engineering Carleton University Ottawa ON Canada

Due to the problem of spectrum underuti-lization and energy inefficiency in wireless commu-nications, the research on energy efficient Cogni-tive Radio Networks （CRNs） has received signifi-cant attention in both industry and academia. In this paper, we consider the problem of optimal spectrum selection and transmission parameters de-sign with the objective of minimizing energy con-sumption in CRNs. Since the system state cannot be directly observed due to miss detections and estimation errors, we formulate the optimal spec-trum access problem as a Partially Observable Markov Decision Process （POMDP）. In particular, the proposed scheme selects the optimal spectrum, modulation and coding scheme, transmission pow-er, and link layer frame size in each time slot ac-cording to the belief state, which captures all the history information of past actions and observa- tions. The optimal policy can be acquired by sol-ving POMDP problem with linear programming based algorithm Sinmlation results show that sig-nificant energy savings can be achieved by the proposed scheme.

关键词： spectrum access cognitive radio POMDP

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不同晶相成分及结晶态的生物活性玻璃体外降解性的研究

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生物医学工程学杂志 2005年第5期22卷 990-994页

作者：张玉梅蔡玉荣王勤涛赵铱民 Monchau f Lefevre A Hildebrand H.f 第四军医大学口腔医学院西安710032 西北有色金属研究院西安710016 法国里尔第二大学生物材料研究实验室

采用sol-gel方法合成生物活性玻璃材料,采用600℃、900℃、1100℃高温处理后,形成不同晶相成分及结晶态的三种材料SG600,SG900和SG1100。原代培养破骨细胞接种在材料表面并培养4h和48h。采用细胞化学法对破骨细胞actin进行标记,采用分... 详细信息

采用sol-gel方法合成生物活性玻璃材料,采用600℃、900℃、1100℃高温处理后,形成不同晶相成分及结晶态的三种材料SG600,SG900和SG1100。原代培养破骨细胞接种在材料表面并培养4h和48h。采用细胞化学法对破骨细胞actin进行标记,采用分光光度计测量Ca和P离子浓度,采用扫描电镜(SEM)观察破骨细胞的形态及吸收陷窝。结果显示,三种材料表面均可显示破骨细胞环状actin。SG600的钙离子浓度明显高于对照组及其他两种材料组,当破骨细胞存在时,三种材料钙磷离子浓度均比无细胞时有所增加。在三种材料表面破骨细胞均形成良好的附着与伸展,吸收陷窝的形态及深度无明显差异。说明生物活性玻璃材料由于晶相成分及结晶度的不同,在体外具有不同的溶解性。体外破骨细胞在三种材料表面均显示出明显的降解活性。

关键词：生物活性玻璃破骨细胞生物降解生物活性玻璃体外成分晶态降解性钙离子浓度破骨细胞 sol-gel 玻璃材料

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Engineering Microneedle Patches for Improved Penetration:Analysis,Skin Models and factors Affecting Needle Insertion

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Nano-Micro Letters 2021年第6期13卷 190-230页

作者： Pooyan Makvandi Melissa Kirkby Aaron RJHutton Majid Shabani Cynthia K.Y.Yiu Zahra Baghbantaraghdari Rezvan Jamaledin Marco Carlotti Barbara Mazzolai Virgilio Mattoli Ryan f.Donnelly Istituto Italiano Di Tecnologia Centre for Materials InterfaceViale Rinaldo Piaggio 3456025 PontederaPisaItaly School of Pharmacy Queen’s University Belfast97 Lisburn RoadBelfast BT97BLUK The BioRobotics Institute Scuola Superiore Sant’AnnaViale Rinaldo Piaggio 3456025 PontederaPisaItaly Paediatric Dentistry and Orthodontics Faculty of DentistryThe University of Hong KongPrince Philip Dental HospitalHong Kong SARChina Department of Chemical Materials and Industrial Production EngineeringUniversity of Naples FedericoⅡ80125 NaplesItaly Center for Advanced Biomaterials for Health Care(iit@CRIB) Italian Institute of Technology80125 NaplesItaly

Transdermal microneedle(MN)patches are a promising tool used to transport a wide variety of active compounds into the *** serve as a substitute for common hypodermic needles,MNs must pierce the human stratum corneum(~10 to 20μm),without rupturing or bending during *** ensures that the cargo is released at the predetermined place and ***,the ability of MN patches to sufficiently pierce the skin is a crucial *** the current review,the pain signal and its management during application of MNs and typical hypodermic needles are presented and *** is followed by a discussion on mechanical analysis and skin models used for insertion tests before application to clinical *** that affect insertion(e.g.,geometry,material composition and cross-linking of MNs),along with recent advancements in developed strategies(e.g.,insertion responsive patches and 3D printed biomimetic MNs using two-photon lithography)to improve the skin penetration are highlighted to provide a backdrop for future research.

关键词： Insertion responsive Implantable microneedles Skin indentation Transdermal microneedles Pain management

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Structural and Magnetic Properties of Mechanically Alloyed Nd_(15)fe_(70)T_(15)N_δ(T=V,Mo) Magnets

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Journal of Materials Science & Technology 1995年第1期11卷 1-4页

作者： Xinguo ZHAO Zhidong ZHANG Wei LIU Qun WAN and Xaokai SUN(Institute of Metal Research, Chinese Academy f Sciences, Shenyang, 110015, China) CHINESE ACAD SCI INST MET RESSHENYANG 110015PEOPLES R CHINA

Structural and magnetic properties of Nd15fe70T15Nδ(T=V, Mo) alloys, made by mechanical alloying (MA) followed by heat-treatment and nitriding, have been investigated *** of annealing temperature on the structure and magnetic properties of the materials were studied by means of X-ray diffraction, AC susceptibility and high field magnetization measurements. Under pure argon atmosphere, the optimum temperatures for the heat treatment are found to be 75 and 850℃ for Nd15fe7015Nδ and Nd15fe70Mo15Nδ respectively. Correspondingly, the following magnetic properties are achieved : (1) Nd15fe70V15Nδ:Br=0.63 T,,HC=8.01kA/cm (10.1 kOe), (BH )max=50.3 kJ/m3 (6 32 MGOe), (2) Nd15fe70Mo15Nδ :Br=0.42 T. iHc=5.6 kA/cm (7.4 kOe), (BH )max=26.6 kJ/m3 (3.34 MGOe)

关键词： fe T=V,Mo T Magnets Structural and Magnetic Properties of Mechanically Alloyed Nd

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Converting lateral scanning into axial focusing to speed up three-dimensional microscopy

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Light(Science & Applications) 2020年第1期9卷 429-440页

作者： Tonmoy Chakraborty Bingying Chen Stephan Daetwyler Bo-Jui Chang Oliver Vanderpoorten Etai Sapoznik Clemens f.Kaminski Tuomas P.J.Knowles Kevin M.Dean Reto fiolka Department of Cell Biology UT Southwestern Medical CenterDallasTXUSA Department of Physics and Astronomy University of New MexicoAlbuquerqueNMUSA Department of Chemical Engineering and Biotechnology University of CambridgeCambridge CB30ASUK Department of Chemistry University of CambridgeLensfield RoadCambridge CB21EWUK Lyda Hill Department of Bioinformatics UT Southwestern Medical CenterDallasTXUSA

In optical microscopy,the slow axial scanning rate of the objective or the sample has traditionally limited the speed of volumetric ***,by conjugating either a movable mirror to the image plane in a remote-focusing geometry or an electrically tuneable lens(ETL)to the back focal plane,rapid axial scanning has been ***,mechanical actuation of a mirror limits the axial scanning rate(usually only 10–100 Hz for piezoelectric or voice coil-based actuators),while ETLs introduce spherical and higher-order aberrations that prevent high-resolution *** an effort to overcome these limitations,we introduce a novel optical design that transforms a lateral-scan motion into a spherical aberration-free axial scan that can be used for high-resolution *** a galvanometric mirror,we scan a laser beam laterally in a remote-focusing arm,which is then back-reflected from different heights of a mirror in the image *** characterize the optical performance of this remote-focusing technique and use it to accelerate axially swept light-sheet microscopy by an order of magnitude,allowing the quantification of rapid vesicular dynamics in three *** also demonstrate resonant remote focusing at 12 kHz with a two-photon raster-scanning microscope,which allows rapid imaging of brain tissues and zebrafish cardiac dynamics with diffraction-limited resolution.

关键词： mirror axial image

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Self Reinforced Barium Titanate Ceramics by Barium Titanate fibres

Self Reinforced Barium Titanate Ceramics by Barium Titanate ...

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The fourth International Conference on Physical and Numerical Simulation of Materials Processing (ICPNS’2004)

作者： José M.f.ferreira Department of Ceramics and Glass Engineering CICECO University of Aveiro 3810-193 Aveiro Portugal

Self reinforced barium titanate ceramics were achieved following a novel routine, namely, by sintering nanosized BaTiO3 particles reinforced with 5-wt.% BaTiO3 fibres, without extra addition of second phase as reinforcing agent. A hydrothermal technique and a cellulose-method were used to synthesize BaTiO3 nano-particles and fibres, respectively. The crystalline phase in the powders and fibres was determined as cubic and tetragonal BaTiO3, respectively. Green bodies were shaped from BaTiO3 particle/BaTiO3 fibre mixtures by slip casting (SC). Rheological measurements indicated that the addition of the fibres facilitate the aqueous processing of the nanopowders. furthermore, the fracture toughness of sintered body (1200℃/2h) was 2.22 MPa·m1/2, higher than that of the SC non-reinforced matrix (1.92 MPa·m1/2). The microstructures and electrical properties of the sintered bodies were investigated. It was found that the reinforced ceramics exhibited improved toughness without significant degrading the dielectric properties.

关键词： Barium titanate fibre Slip casting.

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