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Comparative analysis of microstructure,mechanical,and corrosion properties of biodegradable Mg-3Y alloy prepared by selective laser melting and spark plasma sintering

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Journal of Magnesium and Alloys 2024年第4期12卷 1496-1510页

作者： P.Minárik M.Zemková S.Šašek J.Dittrich M.Knapek F.Lukáˇc D.Koutný J.Jaroš R.Král Faculty of Mathematics and Physics Charles UniversityKe Karlovu 5Praha 12116Czech Republic Research Centre University ofŽilinaUniverzitná8215/1Žilina 01026Slovakia Institute of Plasma Physics of the Czech Academy of Sciences Za Slovankou 1782/318200 Praha 8Czech Republic Institute of Machine and Industrial Design Brno University of TechnologyTechnická2896/2Brno 61669Czech Republic

This work explored possibilities of biodegradable magnesium alloy Mg-3Y preparation by two modern powder metallurgy techniques–spark plasma sintering(SPS)and selective laser melting(SLM).The powder material was consolidated by both methods utilising optimised parameters,which led to very low porosity(∼0.3%)in the SLM material and unmeasurably low porosity in the SPS *** main aim of the study was the thorough microstructure characterisation and interrelation between the microstructure and the functional properties,such as mechanical strength,deformability,and corrosion *** materials showed comparable strength of∼110 MPa in tension and compression and relatively good deformability of∼9%and∼21%for the SLM and SPS materials,*** corrosion resistance of the SPS material in 0.1 M NaCl solution was superior to the SLM one and comparable to the conventional extruded *** digital image correlation during loading and the cross-section analysis of the corrosion layers revealed that the residual porosity and large strained grains have the dominant negative effect on the functional properties of the SLM *** the other hand,one of the primary outcomes of this study is that the SPS consolidation method is very effective in the preparation of the W3 biodegradable alloy,resulting in material with convenient mechanical and degradation properties that might find practical applications.

关键词： Magnesium Yttrium Powder metallurgy Microstructure Mechanical strength Corrosion resistance

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基于光敏耦合定时器的压频转换器的实现（英文）

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Journal of Measurement Science and Instrumentation 2017年第1期8卷 17-20页

作者： Akash Kumar Anindya Debnath Antar Banik Kabirul Islam Mondal Partha Pratim Biswas rik bhattacharyya T K Maiti 德里理工学院应用电子与仪器工程系印度加尔各答700152

研制了基于定时器的压频转换器,电路主要由工作于非稳态多谐振荡器模式下的定时器LM555和两个光敏电阻构成。由于数字存储振荡器测得的定时器输出波频率与所施加的输入电压基本呈线性比例关系,所研制的转换器为类数字输出,因此具有线性... 详细信息

研制了基于定时器的压频转换器,电路主要由工作于非稳态多谐振荡器模式下的定时器LM555和两个光敏电阻构成。由于数字存储振荡器测得的定时器输出波频率与所施加的输入电压基本呈线性比例关系,所研制的转换器为类数字输出,因此具有线性输入/输出关系、体积小、易携带和高性价比等优点。此外,定时器输出波可以直接与PC机、微处理器或微控制器相连,不需要模/数转换器就能完成对输入电压信号的进一步处理。

关键词： LM555定时器非稳态多谐振荡器发光二极管光敏电阻压频转换器数字存储振荡器

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简易转速测量系统设计

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Journal of Measurement Science and Instrumentation 2020年第2期11卷 193-196页

作者： Akash Kumar Anindya Debnath Antar Banik Kabirul Islam Mondal Partha Pratim Biswas rik bhattacharyya T K Maiti Netaji Subhash工程学院应用电子与仪器工程系加尔各答700152西孟加拉科克拉贾尔中央理工学院仪器工程系阿萨姆783370印度

介绍了一种基于定时器的转速测量系统的设计与开发。使用直流电动机的转轴来测量其转速,定时器IC 555用于不稳定模式。使用数字存储示波器(DSO)测量的定时器输出波形的频率几乎与转轴的转速成线性比例,而这个转速又与外部输入电压水平... 详细信息

介绍了一种基于定时器的转速测量系统的设计与开发。使用直流电动机的转轴来测量其转速,定时器IC 555用于不稳定模式。使用数字存储示波器(DSO)测量的定时器输出波形的频率几乎与转轴的转速成线性比例,而这个转速又与外部输入电压水平的变化成线性关系,由此得到了定时器输出波形频率与转速之间的线性关系。该系统的主要优点是线性输入-输出,体积小,便于携带且成本低。

关键词：定时器IC 555 非稳多谐振荡器转速测量

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Public Charging Infrastructure in Germany–A Utilization and Profitability Analysis

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Journal of Modern Power Systems and Clean Energy 2022年第6期10卷 1750-1760页

作者： Benedict J.Mortimer Amandus Dominik Bach Christopher Hecht Dirk Uwe Sauer rik W.De Doncker Institute for Power Generation and Storage Systems at the E.ON Energy Research Center RWTH Aachen UniversityAachenGermany

The current increase in the number of electric vehicles in Germany requires an adequately developed charging *** numbers of public and semi-public charging stations are necessary to ensure sufficient coverage of charging *** order to make the installation worthwhile for the mostly private operators as well as public ones,a sufficient utilization is *** paper gives an overview of the differences in the utilization across the public charging infrastructure in *** this end,a dataset on the utilization of 21164 public and semi-public charging stations in Germany is *** installation and operating costs of various charging stations are modeled and economically evaluated in combination with the utilization *** is shown that in 2019-2020,the average utilization in Germany was rather low,albeit with striking regional *** consider future scenarios allowing the regional development forecasting of economic *** is demonstrated that a growth in electric mobility of 20%-30%per year leads to a large number of economically feasible charging parks in urban agglomeration areas.

关键词： Charging infrastructure charging station utilization electromobility economic analysis

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A Roadmap toward Engineered Nitrogen-Fixing Nodule Symbiosis

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Plant Communications 2020年第1期1卷 131-146页

作者： rik Huisman Rene Geurts Wageningen University Department of Plant SciencesLaboratory of Molecular BiologyDroevendaalsesteeg 1Wageningen 6708PBThe Netherlands

In the late 19th century,it was discovered that legumes can establish a root nodule endosymbiosis with nitrogen-fixing *** after,the question was raised whether it is possible to transfer this trait to non-leguminous *** the past century,an ever-increasing amount of knowledge provided unique insights into the cellular,molecular,and genetic processes controlling this *** addition,recent phylogenomic studies uncovered several genes that evolved to function specifically to control nodule formation and bacterial ***,despite this massive body of knowledge,the long-standing objective to engineer the nitrogen-fixing nodulation trait on nonleguminous crop plants has not been achieved *** this review,the unsolved questions and engineering strategies toward nitrogen-fixing nodulation in non-legume plants are discussed and highlighted.

关键词： nodulation legumes actinorhizal plants Parasponia engineering nitrogen fixation

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The unique structural and functional features of CXCL12

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Cellular & Molecular Immunology 2018年第4期15卷 299-311页

作者： rik Janssens Sofie Struyf Paul Proost Department of Microbiology and Immunology Rega Institute for Medical ResearchLaboratory of Molecular ImmunologyKU LeuvenUniversity of LeuvenLeuven B-3000Belgium

The CXC chemokine CXCL12 is an important factor in physiological and pathological processes, includingembryogenesis, hematopoiesis, angiogenesis and inflammation, because it activates and/or induces migration ofhematopoietic progenitor and stem cells, endothelial cells and most leukocytes. Therefore, CXCL12 activity istightly regulated at multiple levels. CXCL12 has the unique property of existing in six splice variants in humans,each having a specific tissue distribution and in vivo activity. Controlled splice variant transcription and mRNAstability determine the CXCL12 expression profile. CXCL12 fulfills its functions in homeostatic and pathologicalconditions by interacting with its receptors CXC chemokine receptor 4 (CXCR4) and atypical chemokine receptor 3(ACKR3) and by binding to glycosaminoglycans (GAGs) in tissues and on the endothelium to allow a properpresentation to passing leukocytes. Homodimerizaton and heterodimerization of CXCL12 and its receptors can altertheir signaling activity, as exemplified by the synergy between CXCL12 and other chemokines in leukocyte migrationassays. Receptor binding may also initiate CXCL12 internalization and its subsequent removal from theenvironment. Furthermore, CXCL12 activity is regulated by posttranslational modifications. Proteolytic removal ofNH2- or COOH-terminal amino acids, citrullination of arginine residues by peptidyl arginine deiminases or nitrationof tyrosine residues reduce CXCL12 activity. This review summarizes the interactions of CXCL12 with the cellularenvironment and discusses the different levels of CXCL12 activity regulation.

关键词： ACKR3 chemokine CXCL12 CXCR4 regulation

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Implantable cardiac defibrillators in octogenarians

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Journal of Geriatric Cardiology 2023年第1期20卷 23-31页

作者： Maarten Pauwelyn Sebastian Ingelaere Ruben Hoffmann Johan Vijgen Georges H.Mairesse Ivan Blankoff Yves Vandekerckhove Jean-Benoit le Polain de Waroux Bert Vandenberk rik Willems University Hospitals Leuven CardiologyLeuvenBelgium KU Leuven Department of Cardiovascular SciencesLeuvenBelgium UZA Department of CardiologyAntwerpBelgium Jessa Ziekenhuis Department of CardiologyHasseltBelgium Cliniques du Sud Luxembourg Department of CardiologyArlonBelgium CHU Charleroi Department of CardiologyCharleroiBelgium AZ Sint-Jan Department of CardiologyBruggeBelgium University of Calgary Libin Cardiovascular InstituteCalgaryCanada

OBJECTIVE Implantable cardiac defibrillators(ICD)implantation in the very elderly remains *** aimed to describe the experience and outcome of patients over 80 years old implanted with an ICD in *** Data were extracted from the national QERMID-ICD *** implantations performed in octogenarians between February 2010 and March 2019 were *** on baseline patient characteristics,type of prevention,device configuration and all-cause mortality were *** determine predictors of mortality,multivariable Cox proportional hazard regression modelling was *** Nationwide,704 primo ICD implantations were performed in octogenarians(median age 82,IQR 81-83 years;83% male and 45% secondary prevention).During a mean follow-up of 3.1±2.3 years,249(35%)patients died,of which 76(11%)within the first year after *** multivariable Cox regression analysis age(HR=1.15,P=0.004),oncological history(HR=2.43,P=0.027)and secondary prevention(HR=2.23,P=0.001)were independently associated with 1-year mortality.A better preserved left ventricular ejection fraction(LVEF)was associated with a better outcome(HR=0.97,P=0.002).Regarding overall mortality multivariable analysis withheld age,history of atrial fibrillation,centre volume and oncological history as significant *** LVEF was again protective(HR=0.99,P=0.008).CONCLUSIONS Primary ICD implantation in octogenarians is not often performed in *** this population,11%died within the first year after ICD *** age,oncological history,secondary prevention and a lower LVEF were associated with an increased one-year ***,low LVEF,atrial fibrillation,centre volume and oncological history were indicative of higher overall mortality.

关键词： prevention implantation protective

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Decision fusion-based approach for content-based image classification

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International Journal of Intelligent Computing and Cybernetics 2017年第3期10卷 310-331页

作者： Sudeep Thepade rik Das Saurav Ghosh Department of Information Technology Pimpri Chinchwad College of EngineeringPuneIndia Department of Information Technology Xavier Institute of Social ServiceRanchiIndia A.K.Choudhury School of Information Technology University of CalcuttaKolkataIndia

Purpose–Current practices in data classification and retrieval have experienced a surge in the use of multimedia *** of desired information from the huge image databases has been facing increased complexities for designing an efficient feature extraction *** approaches of image classification with text-based image annotation have faced assorted limitations due to erroneous interpretation of vocabulary and huge time consumption involved due to manual ***-based image recognition has emerged as an alternative to combat the aforesaid ***,exploring rich feature content in an image with a single technique has lesser probability of extract meaningful signatures compared to multi-technique feature ***,the purpose of this paper is to explore the possibilities of enhanced content-based image recognition by fusion of classification decision obtained using diverse feature extraction ***/methodology/approach–Three novel techniques of feature extraction have been introduced in this paper and have been tested with four different classifiers *** four classifiers used for performance testing were K nearest neighbor(KNN)classifier,RIDOR classifier,artificial neural network classifier and support vector machine ***,classification decisions obtained using KNN classifier for different feature extraction techniques have been integrated by Z-score normalization and feature scaling to create fusion-based framework of image *** has been followed by the introduction of a fusion-based retrieval model to validate the retrieval performance with classified *** works on content-based image identification have adopted fusion-based ***,to the best of the authors’knowledge,fusion-based query classification has been addressed for the first time as a precursor of retrieval in this ***–The proposed fusion techniques have successfull

关键词： Classification Information fusion Content-based feature extraction Retrieval

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Stratified composite-loaded plasmonic waveguide for sensing biofluids

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Photonics Research 2013年第4期1卷 164-170页

作者： Rimlee Deb Roy rik Chattopadhyay Shyamal K.Bhadra Fiber Optics&Photonics Division CSIR-Central Glass&Ceramic Research Institute196Raja S.C.Mullick RoadJadavpurKolkata 700032India

A new integrated plasmonic waveguide sensor is reported with high sensitivity(1600 nm∕RIU).The integrated structure,loaded with stratified composite,makes this device robust and easy to fabricate on a chip to use as a sensor *** device works on the principle of resonant coupling between surface plasmon and fundamental TM *** selecting proper stratified structure(metal–dielectric)and core glass,one can tune the sensitivity and the range of operating wavelength.

关键词： waveguide loaded composite

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Dye-sensitized Er^(3+)-doped CaF_(2)nanoparticles for enhanced near-infrared emission at 1.5μm

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Photonics Research 2021年第10期9卷 2037-2045页

作者： JING LIU FLAVIA ARTIZZU MIN ZENG LUCA PILIA PIETER GEIREGAT rik VAN DEUN Key Laboratory of Luminescence Analysis and Molecular Sensing Ministry of EducationSchool of Materials and EnergySouthwest UniversityChongqing 400715China Department of Chemistry Ghent UniversityB-9000 GhentBelgium Department of Sciences and Technological Innovation University of Eastern Piedmont“Amedeo Avogadro”15121 AlessandriaItaly Department of Mechanical Chemical and Material EngineeringUniversity of Cagliari09123 CagliariItaly

Lanthanide(Ln)-doped nanoparticles have shown potential for applications in various ***,the weak and narrow absorption bands of the Ln ions(Ln^(3+)),hamper efficient optical pumping and severely limit the emission *** sensitization is a promising way to boost the near-infrared(NIR)emission of Er^(3+),hence promoting possible application in optical amplification at 1.5μm,a region that is much sought after for telecommunication ***,we introduce the fluorescein isothiocyanate(FITC)organic dye with large absorption cross section as energy donor of small-sized(∼3.6 nm)Er^(3+)-doped CaF_(2)*** molecules on the surface of CaF_(2)work as antennas to efficiently absorb light,and provide the indirect sensitization of Er^(3+)boosting its *** this paper,we employ photoluminescence and transient absorption spectroscopy,as well as density functional theory calculations,to provide an in-depth investigation of the FITC→Er^(3+)energy transfer *** show that an energy transfer efficiency of over 89%is achieved in CaF_(2):Er^(3+)@FITC nanoparticles resulting in a 28 times enhancement of the Er^(3+)NIR emission with respect to bare CaF_(2):Er^(3+).Through the multidisciplinary approach used in our work,we are able to show that the reason for such high sensitization efficiency stems from the suitable size and geometry of the FITC dye with a localized transition dipole moment at a short distance from the surface of the nanoparticle.

关键词： process. absorption hence

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