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Emission colour tuning in KLnF_(4):Yb^(3+),Er^(3+)/Ho^(3+)phosphor

Journal of Rare Earths 2024年第1期42卷 57-65,I0002页

作者： Janani K gayathri E Vijayatha V Ramasubramanian S Thiyagarajan p Department of Science and Humanities Nehru Institute of TechnologyKaliapuramThirumalayampalayamCoimbatoreIndia Department of Sciences Amrita School of Physical SciencesAmrita Vishwa VidyapeethamCoimbatoreIndia Department of physics Anna UniversityChennaiIndia

KLnF_(4):Yb^(3+),Er^(3+)/Ho^(3+)(Ln=Y,Yb,gd)phosphors were prepared by solid-state reaction *** each of the Yb^(3+)/Er^(3+)and Yb^(3+)/Ho^(3+)co-doped phosphors independently,phase confirmation and morphological examination were accomplished using the X-ray diffraction technique and scanning electron microscope analysis.X-ray photoelectron spectroscopy analysis shows the charge state and existence of lanthanides and *** luminescence emissions of green and red colour were detected for the synthesized *** changes in the upconverted emission intensities and colour output pertaining to the change of the lanthanide host matrix along with dopants were investigated for the prepared *** the upconversion luminescence,erbium-doped samples exhibit a predominance of red emission while holmium-doped samples display a prevalence of green *** rare-earth Er/Ho doped KYbF4shows strong red emission compared to other ***_(4):Yb,Er/Ho exhibits relatively significant green upconve rsion emissions,while Yb,Er-doped KgdF_(4)host displays a 10-fold increase in green/red emission ratio with an increase in the input power of 20-780 *** photoluminescence studies and decay curve analysis were carried out using UV light excitation for the developed phosphors.A higher lifetime of 2.2 ms was measured for the downshifting red emission in the Ho doped KYbF_(4)*** study suggests a potential for colour tunability in the upconversion and downshifting emissions through host modifications to the fluoride phosphor.

关键词： Rare earths Energy transfer upconversion Downshifting Colour coordinates

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Chronic active and atrophic gastritis as significant contributing factor to the development of gastric cystica profunda

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World Journal of gastroenterology 2024年第17期30卷 2308-2310页

作者： Veronika papp pál Miheller Department of Surgery Transplantation and GastroenterologySemmelweis UniversityBudapest 1082Hungary

gastric cystica profunda(g.p.is an uncommon but underestimated gastric *** precancerous potential determines its *** addition to previous mucosa injury due to operations,biopsy or polypectomy,chronic active and atrophic gastritis may also lead to the development of *** carefully examining the stomach and taking biopsy samples from the susceptible regions,the stage of atrophy can be *** atrophic gastritis is a risk factor for cancer evolvement and it can also contribute to g.p. *** frequently occur close to early gastric cancers(EgCs)or EgC can arise from the cystic *** resection is an effective and minimally invasive treat-ment in g.p.

关键词： gastric cystica profunda Chronic active gastritis Atrophic gastritis Operative Link for gastritis Assessment staging Early gastric cancer Endoscopic resection

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MECHANISM OF SOUND gENERATION BY FLOW OVER TWO CAVITIES IN TWO DIMENSIONS

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Journal of Hydrodynamics 2001年第1期13卷 58-63页

作者： Liu, X.Z. Liu, Y.Z. Miao, g.p. Sch. of Naval Archit. and Ocean Eng. Shanghai Jiaotong Univ. Shanghai 20030 China

The mechanism of sound generation by flow over two cavities in two dimensions is studied by examining the evolution of vorticity, pressure level, spectra and directivity of the generated sound. The study shows that the sound pressure level for two cavities is higher than that for a single cavity. When the distance between the two cavities is large, the interaction between vortices caused by cavities is weak enough to be negligible, so that the results from the acoustic analogy approach coincide with those from the superposition principle. When the distance between the two cavities is relatively small, however, the interaction between vortices becomes stronger and the results from acoustic analogy approach are then larger than those from the superposition principle. Regarding the nonlinear interaction of sound waves in the far field, high harmonic waves can occur when the dimensions of the two cavities are equal, while the sum and difference frequency waves besides the high harmonic waves appear when the dimensions of the two cavities are different.

关键词： Cavitation Computer simulation Hydrodynamics

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Severe acute respiratory syndrome-coronavirus-2(SARS-COV-2)infection of pneumocytes with vaccination and drug therapy:Mathematical analysis and optimal control

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International Journal of Biomathematics 2024年第2期17卷 299-334页

作者： R.Viriyapong.p.Inkhao Department of Mathematics Faculty of Science Naresuan University Phitsanulok65000Thailand

We propose a mathematical model studying a within-host infection dynamics of SARSCoV-2 in *** model incorporates immune response,vaccination and antiviral *** crucial properties of the model-the existence,positivity and boundary of solutions are *** points and the basic reproduction number are *** stability of each equilibrium point is *** control is applied to the model by adding three control variables:vaccination,treatment by Favipiravir and treatment by *** results show that each individual control could reduce SARS-CoV-2 infection in some aspects;however,with a combination of three controls,we obtain the best results in reducing SARS-CoV-2 *** study has emphasized the importance of prevention by vaccine and the antiviral treatments.

关键词： SARS-CoV-2 vaccination drug therapy immune response optimal control

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Construction of 2D/2D Ti_(3)C_(2)T_(x)MXene/CdS heterojunction with photothermal effect for efficient photocatalytic hydrogen production

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Journal of Materials Science & Technology 2024年第4期171卷 1-9页

作者： T.Y.Huang Z.Yang S.Y.Yang Z.H.Dai Y.J.Liu J.H.Liao g.Y.Zhong Z.J.Xie Y.p.Fang S.S.Zhang Key Laboratory for Biobased Materials and Energy of Ministry of Education Guangdong Laboratory for Lingnan Modern AgricultureCollege of Materials and EnergySouth China Agricultural UniversityGuangzhou 510643China School of physics and Optoelectronics South China University of TechnologyGuangzhou 510640China School of Chemical Engineering and Energy Technology Guangdong Provincial Key Laboratory of Distributed Energy SystemsDongguan University of TechnologyDongguan 523808China

The insensitivity of semiconductors to visible and infrared light is a key constraint on the utilization of light energy in photocatalytic *** photocatalysts with full-spectrum absorption through surface engineering is an effective approach to fully harnessing light energy in semiconductor ***,a novel stable Ti_(3)C_(2)T_(x)MXene/CdS heterojunction catalyst is obtained by in-situ epitaxial growth of two-dimensional(2D)CdS nanosheets on 2D MXene interface via a solvothermal *** exceptional light absorption properties of MXene confer outstanding full-spectrum driven photocat-alytic hydrogen evolution capability upon the heterogeneous *** unique 2D/2D structure effectively mitigated the recombination of photogenerated carriers,enhancing the photocatalytic performance of the ***,the composite catalyst exhibits a significantly higher surface temperature of 80.4℃under visible light irradiation at an intensity of 0.1 W/cm^(2),which is 1.84 times higher than that of *** irradiation of visible and near infrared light,the composite catalyst with photothermal ef-fect demonstrates a remarkable hydrogen evolution rate of 65.4 mmol g^(-1)h^(-1),which is 7.2 times higher than that of CdS *** study introduces a novel approach for constructing full-spectrum absorption catalysts and expands the application of the photothermal effect in photocatalytic hydrogen evolution research.

关键词： Two-dimensional structure Heterostructure photothermal effect photocatalyst Hydrogen evolution

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A facile strategy for tuning the density of surface-grafted biomolecules for melt extrusion-based additive manufacturing applications

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Bio-Design and Manufacturing 2024年第3期7卷 277-291页

作者： I.A.O.Beeren g.Dos Santos p.J.Dijkstra C.Mota J.Bauer H.Ferreira Rui L.Reis N.Neves S.Camarero-Espinosa M.B.Baker L.Moroni Department of Complex Tissue Regeneration MERLN Institute for Technology-Inspired Regenerative MedicineMaastricht University6229 ER MaastrichtThe Netherlands 3B’s Research group I3Bs–Research Institute on BiomaterialsBiodegradables and BiomimeticsHeadquarters of the European Institute of Excellence on Tissue Engineering and Regenerative MedicineUniversity of MinhoAveParkZona Industrial da Gandra4805-017 BarcoGuimarãesPortugal ICVS/3B’s-pT government Associate Laboratory 4806-909 Braga/GuimarãesPortugal pOLYMAT University of the Basque Country UPV/EHU20018 Donostia/San SebastiánSpain IKERBASQUE Basque Foundation for Science48009 BilbaoSpain

Melt extrusion-based additive manufacturing(ME-AM)is a promising technique to fabricate porous scaffolds for tissue engi-neering ***,most synthetic semicrystalline polymers do not possess the intrinsic biological activity required to control cell *** of biomolecules on polymeric surfaces of AM scaffolds enhances the bioactivity of a construct;however,there are limited strategies available to control the surface ***,we report a strategy to tune the surface density of bioactive groups by blending a low molecular weight poly(ε-caprolactone)5k(pCL5k)containing orthogonally reactive azide groups with an unfunctionalized high molecular weight pCL75k at different *** porous three-dimensional(3D)scaf-folds were then fabricated using a high weight percentage(75 wt.%)of the low molecular weight pCL *** a proof-of-concept test,we prepared films of three different mass ratios of low and high molecular weight polymers with a thermopress and reacted with an alkynated fluorescent model compound on the surface,yielding a density of 201-561 pmol/cm^(2).Subsequently,a bone morphogenetic protein 2(BMp-2)-derived peptide was grafted onto the films comprising different blend compositions,and the effect of peptide surface density on the osteogenic differentiation of human mesenchymal stromal cells(hMSCs)was *** two weeks of culturing in a basic medium,cells expressed higher levels of BMp receptor II(BMpRII)on films with the conjugated *** addition,we found that alkaline phosphatase activity was only significantly enhanced on films contain-ing the highest peptide density(i.e.,561 pmol/cm^(2)),indicating the importance of the surface *** together,these results emphasize that the density of surface peptides on cell differentiation must be considered at the cell-material ***,we have presented a viable strategy for ME-AM community that desires to tune the bulk and surface functionality via blending of(m

关键词： Additive manufacturing Blending Surface functionalization Surface density Click chemistry Human

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Metric and Upper Dimension of Extended Annihilating-Ideal graphs

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Algebra Colloquium 2024年第2期31卷 221-238页

作者： S.Nithya g.Elavarasi genghua Fan Department of Mathematics St.Xavier's College(Autonomous)Palayamkottai 627002Tamil NaduIndia Afiliated to Manonmaniam Sundaranar University Abishekapatti Tirunelveli 627012Tamil NaduIndia pg and Research Department of Mathematics St.Xavier's College(Autonomous)Palayamkottai 627002Tamil NaduIndia Affiliated to Manonmaniam Sundaranar University Abishekapatti Tirunelveli 627012Tamil NaduIndia 不详

The metric dimension problem is called navigation problem due to its application to robot navigation in *** this concept has wide applications in motion planning,sonar and loran station,and so *** this paper,we study certain results on the metric dimension,upper dimension and resolving number of extended annihilating-ideal graph EAg(R)associated to a commutative ring R,denoted by dim M(EAg(R)),dim+(EAg(R))and res(EAg(R)),*** we prove the finiteness conditions of dim M(EAg(R))and dim+(EAg(R)).In addition,we characterize dim M(EAg(R)),dim+(EAg(R))and res(EAg(R))for artinian rings and the direct product of rings.

关键词： extended annihilating-ideal graph metric dimension upper dimension resolving number

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Effect of scanning strategy on grain structure and crystallographic texture of Inconel 718 processed by selective laser melting

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Journal of Materials Science & Technology 2018年第10期34卷 1799-1804页

作者： H.Y. Wan Z.J. Zhou C.p. Li g.F. Chen g.p. Zhang Shenyang National Laboratory for Materials Science Institute of Metal Research Chinese Academy of Sciences Shenyang 110016 China School of Materials Science and Engineering University of Science and Technology of China Shenyang 110016 China Materials & Manufacturing Qualification group Corporate Technology Siemens Ltd. Beijing 100102 China

Two types of scanning strategies were adopted to study the effect of scanning strategy on grain structure and crystallographic texture of selective laser melted （SLM） Inconel 718. The results show that bidirec-tional scanning without and with a 90°-rotation for every layer produced the bimodal grain structure and the directional columnar grain structure, respectively. Controlling the heat flux direction between the successive layers via scanning strategy enabled the formation of such different grain structures. Fur-thermore, when the 90°-rotation was applied, the competitive grain growth mechanism became more pronounced and the strong cube texture developed.

关键词： Selective laser melting Additive manufacturing Scanning strategy Texture grain structure

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Data-driven evaluation of fatigue performance of additive manufactured parts using miniature specimens

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Journal of Materials Science & Technology 2019年第6期35卷 1137-1146页

作者： H.Y. Wan g.F. Chen C.p. Li X.B. Qi g.p. Zhang Shenyang National Laboratory for Materials Science Institute of Metal Research Chinese Academy of Sciences 72 Wenhua Road Shenyang 110016 China School of Materials Science and Engineering University of Science and Technology of China Shenyang 110016 China Materials Manufacturing Qualification group Corporate Technology Siemens Ltd. China Beijing 100102 China State Key Laboratory of Tribology Tsinghua University Beijing J00084 China

This overview firstly introduces the state-of-the-art research progress in length scale-related fatigue performance of conventionally-fabricated metals evaluated by miniature specimens. Some key factors for size effects sensitive to microstructures including the specimen thickness, grain size and a ratio between them are highlighted to summarize some general rules for size effects. Then, ongoing research progress and new challenges in evaluating the fatigue performance of additive manufactured parts controlled by location-specific defects, microstructure heterogeneities as well as mechanical anisotropy using miniature specimen testing technique are discussed and addressed. Finally, a potential roadmap to establish a data-driven evaluation platform based on a large number of miniature specimen-based experiment data,theoretical computations and the ’big data’ analysis with machine learning is proposed. It is expected that this overview would provide a novel strategy for the realistic evaluation and fast qualification of fatigue properties of additive manufactured parts we have been facing to.

关键词： Additive manufacturing Miniature specimen Fatigue Size effect Location-specific Data analysis

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Multiple sclerosis drug repurposing for neuroregeneration

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Neural Regeneration Research 2024年第3期19卷 507-508页

作者： peter göttle Michael Dietrich patrick Küry Department of Neurology Medical FacultyHeinrich-Heine UniversityDüsseldorfGermany

Multiple sclerosis(MS)is an autoimmune disorder of the central nervous system(CNS)and is primarily characterized by immune cell infiltration leading to relapses followed by remission phases and a disease course turning.p.ogressive over time with neurodegenerative processes taking over(Amin and Hersh,2023).Of note,beyond relapse-associated worsening early in disease progression independent of relapse activity may arise independently of relapse activity and can occur in all ***-mediated damage of myelin sheaths and the subsequent loss of mature oligodendrocytes are resulting in impaired axonal integrity,neurodegeneration and accounts for irreversible neuronal damage(Kuhlmann et al.,2023).The current landscape of available disease-modifying therapies comprises mainly immunomodulatory drugs that effectively diminish relapses and slow down progression at the onset form of the disease,namely relapsing MS(RMS).In this regard,a number of drugs have been approved as disease-modifying therapies for MS by US Food and Drug Administration and European Medicines Agencies(Box 1).

关键词： drugs impaired irreversible

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