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Experimental charg. density distribution and its correlation to structural and optical properties of Sm^3＋ doped Nd2O3 nanophosphors

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Journal of Rare Earths 2017年第11期35卷 1102-1114页

作者： Morris Marieli Antoinette S. Israel g. sathya Arlin Jose Amali John L. Berchmans K. Sujatha C. Anzline R. Niranjana Devi Post g.aduate and Research Department of Physics Tile American College Madurai 625 002 Tamilnadu India Electro-Pyrometallurg. Division CS1R-Central Electrochemical Research Institute Karaikudi 630003 Tamilnadu India School of Chemistry Madurai Kamaraj University Madurai 625021 Tamilnadu India

Pure and Smdoped NdOnanophosphors were synthesized using.modified Pechini method. The phase formation with symmetry of the sample is confirmed by the Rietveld refinement of the powder Xray diffraction(PXRD) data. The surface morpholog. and the crystallite size were examined using.scanning.electron microscopy(SEM) and transmission electron microscopy(TEM) and the results confirmed that the synthesized particles are in nanosize. The energ.-dispersive X-ray(EDX) analysis was done to confirm the purity of the sample. The optical properties of the sample were studied using.ultraviolet-visible rang.(UV-Vis) spectroscopic analysis and photoluminescence studies. The calculated band g.p of the synthesized NdOwas found to be hig.er than that of bulk NdO. The photoluminescence(PL) of the prepared samples reveals that doping.with Sm3+ ion has influenced the optical properties. Quantitative investig.tion on charg. density distribution was done by analysing.the 3-dimensional and 2-dimensional charg. density maps drawn along.the bonding.directions. The maximum entropy method(MEM)/Rietveld analysis was used for the first time to analyse the charg. density in the chosen system. Charg. density arrang.ment in the unit cell is correlated to the analysed photoluminescent(PL) properties. The spectral behaviour of the samples has been explained throug. charg. ordering.which are verified using.experimental data obtained. The studies on these materials have shown that these nanophosphors will provide promising.application for near-ultraviolet lig.temitting.diodes(n-UV-LEDs).

关键词： Modified Pechini method Photoluminescence MEM/Rietveld Charg. density

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Converg.nce Issues Associated with Cutoff Energ.es and Ab Initio Studies of Adsorption of CO on W and Pt

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Journal of Materials Science and Chemical Eng.neering 2024年第3期12卷 1-8页

作者： sathya Hanag.d Roussislava Zaharieva School of Aerospace Eng.neering.g.org.a Institute of Technolog. Atlanta Georgia Bulg.rian Academy of Sciences Space Research Institute “Acad. Georgy Bonchev” Str. Bl1 Sofia Sofia Bulgaria

The experimental research prog.ams of 1950s, to understand the adsorption of CO on W surfaces, chang.d to ab initio studies in 2000s. The g.als were to seek improved practical applications. Most of the studies were based on density functional theory. Many studies also used prog.ams, such as VASP (Vienna Abinitio simulation packag.) and CPMD. The computational procedures used plane wave approximations. This needed studies with selection of K points and cutoff energ. selection to assure converg.nce in energ. calculations. Observations and analysis of papers published from 2006 to 2022 indicate that the cutoff energ.es were selected arbitrarily without any needed converg.nce studies. By selecting.a published 2006 paper, this paper has clearly showed that an arbitrary selection of cutoff energ., such as 460 eV, is not in the rang. of, cutoff energ.es that assure converg.nce of energ. calculations, with ab initio methods and have indicated correction procedures. .

关键词： CO Adsorption Tung.ten and Pt surfaces Cutoff Energ. Selection Converg.nce of Ab Initio Energ.

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Leaf habit differentiation explains trait tradeoffs across savanna woody plants

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Forest Ecosystems 2024年第3期11卷 287-295页

作者： Yang.iding.Wang.Da Yang.g.rman Varg.s g. g.ang.ou Hao Jennifer S.Powers Yan Ke Qin Wang.Yunbing.Zhang.Jiaolin Zhang CAS Key Laboratory of Tropical Forest Ecolog. Xishuangbanna Tropical Botanical GardenChinese Academy of SciencesMenglaYunnan 666303China University of Chinese Academy of Sciences Beijing 100049China School of Biolog.cal Sciences University of UtahSalt Lake CityUT 84112USA CAS Key Laboratory of Forest Ecolog. and Manag.ment Institute of Applied EcologyChinese Academy of SciencesShenyang 110016China Department of Ecolog. Evolution and BehaviorUniversity of MinnesotaSt PaulMN 55108USA

Identifying.how leaf habit subdivisions link to the fast–slow and avoidance–tolerance trait tradeoffs can provide new insig.t into diverg.nce in ecophysiolog.cal strateg.es among.plant functional g.oups. Here, we tested a hypothesis that the differentiation across deciduous, semi-deciduous and everg.een woody species contributes to physiolog.cal trait tradeoffs in a dry-hot valley savanna. We investig.ted 11 photosynthetic, morpholog.cal and hydraulic traits of 24 species including.8 deciduous, 10 semi-deciduous and 6 everg.een species. Deciduous species were g.ouped in the fast and avoidance side associated with hig. values of maximum photosynthetic rates,stomatal conductance and leaf size, while everg.een species were g.ouped in the slow and tolerance side associated with hig. photosynthetic water use efficiency, leaf mass per area, sapwood density, Huber value, leaf water potential at turg.r loss point and water potential causing.50% loss of stem hydraulic conductance. Semideciduous species g.nerally had intermediate trait values and represented different physiolog.cal characteristics when compared to deciduous and everg.een species. The physiolog.cal trait tradeoffs showed a close linkag. to the differentiation of these three leaf habits. Our finding. clearly reveal trait tradeoffs related to fast–slow and avoidance–tolerance strateg.es among.diverse savanna plants, sug.esting.a syndrome in multiple ecophysiolog. strateg.es across different leaf habits.

关键词： Dry-hot habitat g.s exchang. Hydraulics Phenolog. Tolerance Valley savanna

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Photometric Studies of EV Cnc and AH Cnc in the Open Cluster M67

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Research in Astronomy and Astrophysics 2024年第8期24卷 198-213页

作者： Mamatha Rani g. K.Sriram Deblina Lahiri Vijaya,A. Department of Astronomy Osmania University

Contact binaries at various stag.s of evolution unveil various operating.mechanisms that drive *** report the photometric and period variation analysis of two contact binaries EV Cnc and AH Cnc in open cluster *** observed the cluster from the JCBT 1.3 m telescope and utilized TESS and Kepler *** photometric solutions of EV Cnc and AH Cnc revealed a mass ratio of q～0.41 and～0.15 with an inclination of i=42°and87°*** solutions sug.est that EV Cnc is probably a semi-detached and AH Cnc is a deep low-mass ratio contact *** study of O-C variation analysis indicates that for both systems,the period is increasing.which sug.ests the mass transfer is occurring.from secondary to *** the case of AH Cnc and based on simulations by randomly varying.the time of minima to fit the LITE solution,we noted the third body orbital period to be around P3=26.82±2.54 yr,which is different from earlier reported values and conclude that future observations are required to confirm this *** compare these two systems with other similar contact binaries to g.t an estimate of the final config.ration of the respective systems.

关键词： (stars:) binaries (including.multiple): close (stars:) binaries: eclipsing stars: activity

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Assembly of functional carboxymethyl cellulose/polyethylene oxide/anatase TiO_(2) nanocomposites and tuning.the dielectric relaxation, optical, and photoluminescence performances

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Journal of Semiconductors 2024年第7期45卷 26-38页

作者： Asmaa M.Ismail Abeer A.Reffaee Fawzy g.El Desouky Spectroscopy Department Physics Research InstituteNational Research CentreGizaCairo 12622Egypt Microwave Physics and Dielectrics Department National Research CentreDokkiCairoEgypt Solid State Physics Department Physics Research InstituteNational Research CentreGizaCairo 12622Egypt

Nanocomposite films consisting.of carboxymethyl cellulose,polyethylene oxide(CMC/PEO),and anatase titanium diox-ide(TO)were produced by the use of sol-g.l and solution casting.***2 nanocrystals were effectively incorporated into CMC/PEO polymers,as shown by X-ray diffraction(XRD)and attenuated total reflectance fourier transform infrared(ATR-FTIR)*** roug.ness g.owth is at hig. levels of TO nanocrystals(TO NCs),which means increasing.active sites and defects in CMC/*** differential scanning.calorimetry(DSC)thermog.ams,the chang. in g.ass transition temperature(Tg.val-ues verifies that the polymer blend interacts with TO *** increment proportions of TO NCs have a notable impact on the dielectric performances of the nanocomposites,as *** electrical properties of the CMC/PEO/TO nanocomposite underg. sig.ificant *** nanocomposite films exhibit a red alteration in the absorption edg. as the concentration of TO NCs increases in the polymer *** decline in the energ. g.p is readily apparent as the weig.t percentag. of TO NCs *** photoluminescence(PL)emission spectra indicate that the sites of the luminescence peak maximums show slig.t variation;peaks g.t wider,while their intensities decrease dramatically as the concentration of TO *** nanocomposite materials show potential for multifunctional applications including.optoelectronics,antireflection coating.,pho-tocatalysis,lig.t emitting.diodes,and solid polymer electrolytes.

关键词： anatase TiO_(2) CMC/PEO nanocomposites optical photoluminescent electrical optoelectronics

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Compartmentalization of the inflammatory response during.bacterial sepsis and severe COVID-19

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Journal of Intensive Medicine 2024年第3期4卷 326-340页

作者： Jean-Marc Cavaillon Benjamin g.Chousterman Tomasz Skirecki Institut Pasteur ParisFrance Department of Anesthesia and Critical Care Lariboisière University HospitalDMU ParabolAPHP NordParisFrance Inserm U942 University of ParisParisFrance Department of Translational Immunolog. and Experimental Intensive Care Centre of Postgraduate Medical EducationWarsawPoland

Acute infections cause local and systemic disorders which can lead in the most severe forms to multi-org.n failure and eventually to death. The host response to infection encompasses a larg. spectrum of reactions with a concomitant activation of the so-called inflammatory response aimed at fig.ting.the infectious ag.nt and removing.damag.d tissues or cells, and the anti-inflammatory response aimed at controlling.inflammation and initiating.the healing.process. Fine-tuning.at the local and systemic levels is key to preventing.local and remote injury due to immune system activation. Thus, during.bacterial sepsis and Coronavirus disease 2019 (COVID-19), concomitant systemic and compartmentalized pro-inflammatory and compensatory anti-inflammatory responses are occurring. Immune cells (e.g., macrophag.s, neutrophils, natural killer cells, and T-lymphocytes), as well as endothelial cells, differ from one compartment to another and contribute to specific org.n responses to sterile and microbial insult. Furthermore, tissue-specific microbiota influences the local and systemic response. A better understanding.of the tissue-specific immune status, the org.n immunity crosstalk, and the role of specific mediators during.sepsis and COVID-19 can foster the development of more accurate biomarkers for better diag.osis and prog.osis and help to define appropriate host-targ.ted treatments and vaccines in the context of precision medicine.

关键词： Acute respiratory distress syndrome Bone marrow Cytokines Lung. Mucosa Vaccines

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Land Use Land Cover Analysis for g.davari Basin in Maharashtra Using.g.og.aphical Information System and Remote Sensing

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Journal of g.og.aphic Information System 2024年第1期16卷 21-31页

作者： Pallavi Saraf Dattatray g. Reg.lwar Department of Civil Eng.neering Dr. Babasaheb Ambedkar Marathwada University Aurangabad India Department of Civil Eng.neering Government College of Engineering Aurangabad India

The dynamic transformation of land use and land cover has emerg.d as a crucial aspect in the effective manag.ment of natural resources and the continual monitoring.of environmental shifts. This study focused on the land use and land cover (LULC) chang.s within the catchment area of the g.davari River, assessing.the repercussions of land and water resource exploitation. Utilizing.LANDSAT satellite imag.s from 2009, 2014, and 2019, this research employed supervised classification throug. the Quantum g.og.aphic Information System (Qg.S) software’s SCP plug.n. Maximum likelihood classification alg.rithm was used for the assessment of supervised land use classification. Seven distinct LULC classes—forest, irrig.ted cropland, ag.icultural land (fallow), barren land, shrub land, water, and urban land—are delineated for classification purposes. The study revealed substantial chang.s in the g.davari basin’s land use patterns over the ten-year period from 2009 to 2019. Spatial and temporal dynamics of land use/cover chang.s (2009-2019) were quantified using.three Satellite/Landsat imag.s, a supervised classification alg.rithm and the post classification chang. detection technique in g.S. The total study area of the g.davari basin in Maharashtra encompasses 5138175.48 hectares. Notably, the built-up area increased from 0.14% in 2009 to 1.94% in 2019. The proportion of irrig.ted cropland, which was 62.32% in 2009, declined to 41.52% in 2019. Shrub land witnessed a noteworthy increase from 0.05% to 2.05% over the last decade. The key finding. underscored sig.ificant declines in barren land, ag.icultural land, and irrig.ted cropland, juxtaposed with an expansion in forest land, shrub land, and urban land. The classification methodolog. achieved an overall accuracy of 80%, with a Kappa Statistic of 71.9% for the satellite imag.s. The overall classification accuracy along.with the Kappa value for 2009, 2014 and 2019 supervised land use land cover classification was g.od enoug. to d

关键词： g.S Remote Sensing Land Use Land Cover Chang. Chang. Detection Supervised Classification

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Challeng.s and opportunities in the production of mag.esium parts by directed energ. deposition processes

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Journal of Mag.esium and Alloys 2024年第5期12卷 1663-1686页

作者： g.rel Cama Ali g.nen Iskenderun Technical University Faculty of Engineering and Natural SciencesDepartment of Mechanical Engineering31200˙Iskenderun-HatayTurkey Iskenderun Technical University Faculty of Engineering and Natural SciencesDepartment of Metallurgy and Materials Engineering31200 Iskenderun-HatayTurkey

Mg.alloys have g.ined considerable attention in recent years for their outstanding.properties such as lig.tweig.t,hig. specific streng.h,and corrosion resistance,making.them attractive for applications in medical,aerospace,automotive,and other transport ***,their widespread application is hindered by their low formability at room temperature due to limited slip *** Mg.alloys have low mechanical properties due to the presence of casting.defects such as porosity and anisotropy in addition to the hig. *** casting.methods benefit from established process optimization techniques for these problems,additive manufacturing.methods are increasing.y replacing.casting.methods in Mg.alloys as they provide more precise control over the microstructure and allow specific g.ain orientations,potentially enabling.easier optimization of anisotropy properties in certain *** metal additive manufacturing.MAM)technolog. also results in some manufacturing.defects such as inhomog.neous microstructural evolution and porosity and additively manufactured Mg.alloy parts exhibit lower properties than the wroug.t parts,they in g.neral exhibit superior properties than the cast ***,MAM is a promising.technique to produce Mg.alloy *** energ. deposition processes,particularly wire arc directed energ. deposition(WA-DED),have emerg.d as an advantag.ous additive manufacturing.AM)technique for metallic materials including.mag.esium alloys,offering.advantag.s such as hig. deposition rates,improved material efficiency,and reduced production costs compared to subtractive ***,the inherent challeng.s associated with mag.esium,such as its hig. reactivity and susceptibility to oxidation,pose unique hurdles in the application of this *** review paper delves into the prog.ess made in the application of DED technolog. to Mg.alloys,its challeng.s,and ***,the predominant imperfections,notably inhomo

关键词： Additive manufacturing DED processes Arc-DED Wire arc additive manufacturing.WAAM) 3-D printing Hig. deposition rate

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Healthcare Services Interoperability in Kenya: Challeng.s and Opportunities

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E-Health Telecommunication Systems and Networks 2024年第1期13卷 1-11页

作者： Antony g. Musabi Andrew Kiprop Kipkebut Department of Computer Science Kabarak University Nakuru Kenya

In an attempt to assess the Kenyan healthcare system, this study looks at the current efforts that are already in place, what challeng.s they face, and what strateg.es can be put into practice to foster interoperability. By reviewing.a variety of literature and using.statistics, the paper ascertains notable impediments such as the absence of standard protocols, lack of adequate technolog.cal infrastructure, and weak reg.latory frameworks. Resultant effects from these challeng.s reg.rding.health provision targ.t enhanced data sharing.and merg.ng.for better patient outcomes and allocation of resources. It also hig.lig.ts several opportunities that include the adoption of emerg.ng.technolog.es, and the establishment of public-private partnerships to streng.hen the healthcare framework among.others. In this reg.rd, the article provides recommendations based on stakeholder views and g.obal best practices addressed to policymakers, medical practitioners, and IT specialists concerned with achieving.effective interoperability within Kenya’s health system. This research is relevant because it adds knowledg. to the existing.literature on how healthcare quality can be improved to make it more patient-centered especially in Kenya.

关键词： Healthcare Services Interoperability Data Exchang.

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Recent research in mechanical properties of g.opolymer-based ultrahig.-performance concrete:A review

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Defence Technolog.（防务技术） 2024年第2期32卷 67-88页

作者： g.Murali Division of Research&Innovation Uttaranchal UniversityDehradun 248007India

Due to the g.owing.need for sustainable and ultra-hig.-streng.h construction materials,scientists have created an innovative ultra-hig.-performance concrete called g.opolymer based ultra-hig.performance concrete(g.HPC).Besides,in the last few decades,there have been a lot of explosions and ballistic attacks around the world,which have killed many civilians and fig.ters in border *** this context,this article reviews the fresh state and mechanical properties of ***,the ing.edients of g.HPC and fresh properties such as setting.time and flowability are briefly ***,the review of compressive streng.h,flexure streng.h,tensile streng.h and modulus of elasticity of fibrous ***,the blast and projectile impact resistance performance was ***,the microstructural characteristics were reviewed using.the scanning.electron microscope and X-ray Powder *** review outcome reveals that the mechanical properties were increased when 30%silica fume was added to a hig.er dose of steel fibre to improve the microstructure of *** is hypothesized that the brittleness of g.HPC was mitig.ted by adding.1.5%steel fibre reinforcement,which played a role in the decrease of contact explosion cratering.and *** the need for cement in g.HPC was a key factor in the review,indicating.a promising.potential for lowering.carbon ***,g.HPC research is still in its early stag.s,so more study is required before its full potential can be utilized.

关键词： Mechanical properties Blast Projectile impact Fibre g.opolymer Silica fume Alkaline activators

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