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photoluminescence,structural and antibacterial properties of co-dopedβ-Ca_(3)(pO_(4))_(2)-type phosphates Ca_(8)CuRe(pO_(4))_(7)(Re=eu-er)

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Journal of Rare earths 2024年第9期42卷 1658-1668,I0002页

作者： Ivan v.Nikiforov ekaterina v.Iliin Bogdan I.Lazoryak Sergey m.Aksenov pavel v.Slukin dina v.deyneko department of Chemistry Lomonosov Moscow State University119991MoscowRussia Laboratory of Arctic mineralogy and material Sciences Kola Science CentreRussian Academy of Sciences184209ApatityRussia geological Institute Kola Science CentreRussian Academy of Sciences184209ApatityRussia State Scientific Center of Applied microbiology and Biotechnology of Rospotrebnadzor 24 Block A142279ObolenskRussia

Novel Ca_(8)CuRe(pO_(4))_(7)where Re^(3+)=eu^(3+),Tb^(3+),dy^(3+),Ho^(3+)and er^(3+)were synthesized by a solid-state method in *** structures of the samples were characterized by powder X-ray diffraction using Rietveld refinement to determine the occupation of crystal *** samples are found to have a centrosymmetric structure with space group R3c,as shown by dielectric *** synthesized Ca_(8)CuRe(pO_(4))_(7)samples have multifunctional *** Cu^(2+)ions provide antibacterial properties,while the rare earth elements ions exhibit luminescence properties,and theβ-Ca_3(pO_(4))_(2)-type host is *** photoluminescence properties of Re^(3+)ions were studied and compared with other simmilar Ca_(8)mRe(pO_(4))_(7)phosphates,where m is a divalent *** photoluminescence intensity quenching in terms of energy transfer from Re^(3+)to Cu^(2+)is *** bioactive properties were studied in relation to antibacterial activity against *** and *** syntesized Ca_(8)CuRe(pO_(4))_(7)samples demonstrate very high and stable inhibition of bacteria *** correlation between crystal structure and properties is *** combining multiple approaches to the directio nal design of such materials,several important properties within a single chemical compound to achieve biovisualization and bioactive properties simultaneously can be combined.

关键词： β-Ca_(3)(pO_(4))_(2) Whitlockite-type structure Bioactive phosphates TCp photoluminescence Rare earths

efficient Real-Time devices Based on Accelerometer Usingmachine Learning for HAR on Low-performancemicrocontrollers

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Computers, materials and Continua 2024年第1期81卷 1729-1756页

作者： vi m.-T. Tran d.-N. Thuong v.T. Linh N.N. Tran d.-T. Faculty of electrical and electronic engineering Phenikaa University Hanoi City 100000 Viet Nam Institute of Information Technology Vietnam Academy of Science and Technology Hanoi City 100000 Viet Nam Faculty of Information Technology and Communication Phuong Dong University Hanoi City 100000 Viet Nam graduate University of Sciences and Technology Vietnam Academy of Science and Technology Hanoi City 100000 Viet Nam International School-vietnam National University Hanoi City 100000 Viet Nam

Analyzing physical activities through wearable devices is a promising research area for improving health assessment. This research focuses on the development of an affordable and real-time Human Activity Recognition (HAR) system designed to operate on low-performance microcontrollers. The system utilizes data from a bodyworn accelerometer to recognize and classify human activities, providing a cost-effective, easy-to-use, and highly accurate solution. A key challenge addressed in this study is the execution of efficient motion recognition within a resource-constrained environment. The system employs a Random Forest (RF) classifier, which outperforms gradient Boosting decision Trees (gBdT), Support vectormachines (Svm), and k-Nearest Neighbors (kNN) in terms of accuracy and computational efficiency. The proposed featuresAverage absolute deviation (AAd), Standard deviation (STd), Interquartile range (IQR), Range, and Root mean square (RmS). The research has conducted numerous experiments and comparisons to establish optimal parameters for ensuring system effectiveness, including setting a sampling frequency of 50 Hz and selecting an 8-s window size with a 40% overlap between *** conducted on both theWISdmpublic dataset and a self-collected dataset, focusing on five fundamental daily activities: Standing, Sitting, Jogging,Walking, andWalking the stairs. The results demonstrated high recognition accuracy, with the system achieving 96.7% on the WISdm dataset and 97.13% on the collected dataset. This research confirms the feasibility of deployingHAR systems on low-performance microcontrollers and highlights the system's potential applications in patient support, rehabilitation, and elderly care. © 2024 The Authors. published by Tech Science press.

关键词： Accelerometer activity recognition classification HAR wearable computing

Converting TRex-RgB green-channel data to 557.7 nm auroral intensity:methodology and initial results

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earth and planetary physics 2024年第1期8卷 258-274页

作者： Jun Liang d.m.gillies e.Spanswick e.F.donovan University of Calgary CalgaryT2N 1N4Canada

The recently deployed Transition Region explorer(TRex)-RgB(red-green-blue)all-sky imager(ASI)is designed to capture“true color”images of the aurora and *** the 557.7 nm green line is usually the brightest emission line in visible auroras,the green channel of a TRex-RgB camera is usually dominated by the 557.7 nm *** this rationale,the TRex mission does not include a specific 557.7 nm imager and is designed to use the RgB green-channel data as a proxy for the 557.7 nm *** this study,we present an initial effort to establish the conversion ratio or formula linking the RgB green-channel data to the absolute intensity of 557.7 nm auroras,which is crucial for quantitative uses of the RgB *** illustrate two approaches:(1)through a comparison with the collocated measurement of green-line auroras from the TRex spectrograph,and(2)through a comparison with the modeled green-line intensity according to realistic electron precipitation flux measurements from low-earth-orbit satellites,with the aid of an auroral transport *** demonstrate the procedures and provide initial results for the TRex-RgB ASIs at the Rabbit Lake and Lucky Lake *** RgB response is found to be *** conversion ratios or formulas between RgB green-channel data and the green-line auroral intensity are given and can be applied immediately by TRex-RgB data *** methodology established in this study will also be applicable to the upcoming SmILe ASI mission,which will adopt a similar RgB camera system in its deployment.

关键词： TRex RgB green-line aurora auroral transport model

Nanomotion of bacteria to determine metabolic profile

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Nanotechnology and precision engineering 2024年第1期7卷 1-9页

作者： S.N.pleskova e.v.Lazarenko N.A.Bezrukov R.N.kriukov A.v.Boryakov m.e.dokukin S.I.Surodin Research Laboratory of Scanning probe microscopy Lobachevsky State University of Nizhny NovgorodNizhny Novgorod 603950Russia department of Nanotechnology and Biotechnology Nizhny Novgorod State Technical University n.a.R.E.AlekseevNizhny Novgorod 603950Russia Sarov physics and Technology Institute National Research Nuclear University MEPhISarov 607186Russia

In addition to their visible motion such as swimming(e.g.,with the help ofﬂagella),bacteria can also exhibit nanomotion that is detectable only with highly sensitive instruments,and this study shows that it is possible to detect bacterial nanomotion using an AFm detection *** results show that the nanomotion characteristics depend on the bacterial strain,and that nanomotion can be used to sense the metabolic activity of bacteria because the oscillations are sensitive to the food preferences of the bacteria and the type of surrounding medium.

关键词： Nanomotion Bacteria Cantilever Oscillation Atomic force microscopy metabolism

Olefin polymerization Behavior of Titanium(Iv) Complexes with Fluorinated and Non-fluorinated Aliphatic phenoxyimine Ligands

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Chinese Journal of polymer Science 2024年第1期42卷 52-62,I0007页

作者： vladislav A.Tuskaev kasim F.magomedov Svetlana Ch.gagieva dmitry A.kurmaev yulia v.Nelyubina evgenii k.golubev maria d.evseeva viktor g.vasil'ev galina g.Nikiforova mikhail I.Buzin vyacheslav S.Bogdanov Boris m.Bulychev department of Chemistry M.V.Lomonosov Moscow State UniversityMoscow 119992Russian Federation A.N.Nesmeyanov Institute of Organoelement Compounds Russian Academy of SciencesMoscow119991Russian Federation enikolopov Institute of Synthetic polymer materials Russian Academy of SciencesMoscow 117393Russian Federation

A series of Ti(Ⅳ) dichloride and dialkoxide com plexes with phenoxyimine ligands containing fluorinated and nonfluorinated aliphatic imine fragments have been *** molecular structures of complexes 1 and 4 were established by single-crystal X-ray diffraction *** complexes adopt a distorted octahedral coordination structure around the titanium atom and two oxygen atoms are situated in trans position while two nitrogen atoms and two outgoing ligands(Cl or iprO) are situated in cis *** of activators(mmAO-12 and combinations et_nAICl_(3-n)+Bu_(2)mg) and outgoing ligand(Cl or iprO) nature on the catalytic activity and properties of the resulting polymers was *** Ti complexes,despite the nature of the outgoing ligands(Cl or iprO) in the presence of Al/mg activators,was found to display a high ethylene polymerization activity in the range 1600-3830 kg_(polymer)·mol_(Ti)^(-1)·h^(-1)·atm^(-1) with a viscosity average molecular weight(m_v) value in the range 1.1×10~6-7.1×10~6 dalton(da).The resulting UHmWpe can be processed by a solventless method into high-strength and high-modulus oriented *** rheological characteristics of a polymer melt have been *** absence of a cross-over point did not allow to compare the values of the molecular weight distribution of polymers obtained on fluorinated and non-fluorinated pre-catalysts,however,the estimation of the entanglement density is in good agreement with the mechanical characteristics of oriented film *** activation with methylalumoxane,the activity of the com plexes decreased very significantly;however,a polymer with a molecular weight of about 12 million da was *** the process of ethylene/octene-1 copolymerization,fluorine-containing precatalysts showed a clear advantage over non-fluorinated analogues both in activity and in comonomer content.

关键词： FI catalysts Titanium(Iv) (Co)polymerization Al/mg co-catalyst Ultra-high molecular weight polyethylene

prompt neutron emission in ^(250)No spontaneous fission associated with ground and isomeric state decays

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Chinese physics C 2024年第6期48卷 112-117页

作者： R.S.mukhin A.v.Isaev A.v.Andreev m.L.Chelnokov v.I.Chepigin H.m.devaraja I.N.Izosimov A.A.kuznetsova O.N.malyshev A.g.popeko yu.A.popov A.Rahmatinejad B.Sailaubekov T.m.Shneidman e.A.Sokol A.I.Svirikhin m.S.Tezekbayeva m.A.Bychkov A.v.yeremin O.dorvaux B.gall k.kessaci k.Hauschild A.Lopez-martens Joint Institute for Nuclear Research Dubna141980Russia dubna State University Dubna141982Russia Institute of Nuclear physics Almaty050032Kazakhstan L.N.gumilyov eurasian National University Astana010008Kazakhstan kazan Federal University Kazan420008Russia Universitéde Strasbourg CNRSStrasbourg67000France IJCLab IN2P3-CNRSUniversitéParis-SaclayOrsay91400France

The complete-fusion reaction^(204)pb(^(48)Ca,2n)^(250)No was used to study two activities of^(250)No with distinct half-lives.A total of 1357 events were observed in the SFiNx neutron detection *** average number of neutrons emitted per spontaneous fission of^(250)No was determined to be(4.1±0.1).The unusually symmetrical shape of the prompt neutron multiplicity distribution was restored and presented for the first *** tests were performed to compare the prompt neutron multiplicity distributions associated with the ground state and k-isomer state decays.

关键词： spontaneous fission prompt neutrons actinide

Specificity of electrophysical and gas-sensitive properties of nanocomposite ZnO–TiO_(2) films formed by solid-phase pyrolysis

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ChemPhysMater

Chemphysmater 2024年第3期3卷 314-319页

作者： victor v.petrov maria g.volkova Alexsandra p.Ivanishcheva gleb v.Tolstyak ekaterina m.Bayanb Institute of Nanotechnologies Electronicsand Equipment EngineeringSouthern Federal UniversityTaganrog 347922Russia Faculty of Chemistry Southern Federal UniversityRostov-on-Don 344090Russia

ZnO–TiO_(2) thin films containing 0.5 mol%,1.0 mol%,and 5.0 mol%ZnO were synthesized by oxidative solidphase *** materials contained anatase and rutile phases with particle size of 6–13 nm,as confirmed using X-ray phase analysis and scanning electron *** a certain number of ZnO crystallites appeared in the TiO_(2) film structure in the temperature range of room temperature to 220℃,a two-level response of the film resistance was observed,differing by approximately 10%,as obtained by electrophysical *** two-level response correlates with the formation of two donor energy levels of 0.28 and 0.33 ev in the band structure of the ZnO–TiO_(2) *** donor level with a higher activation energy corresponded to the Ti vacancy(v−Ti),and that with a lower activation energy corresponded to the Zn vacancy(v−Zn).Two levels of gas-sensitive properties were noted for 0.5ZnO–TiO_(2),1ZnO–TiO_(2),and 5ZnO–TiO_(2) under the influence of 50 ppm NO_(2) at 250℃.Such two-level responses can be ascribed to the pinning of the Fermi level on ZnO and TiO_(2) *** mechanism of the beak-shaped and two-level responses of sensors based on composite nanomaterials when exposed to various gases was elucidated.

关键词： Thin film ZnO TiO_(2) Nanocomposites pyrolysis gas sensors

exploring van der Waals materials with high anisotropy:geometrical and optical approaches

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Light(Science & Applications) 2024年第4期13卷 645-653页

作者： Aleksandr S.Slavich georgy A.ermolaev mikhail k.Tatmyshevskiy Adilet N.Toksumakov Olga g.matveeva dmitriy v.grudinin kirill v.voronin Arslan mazitov konstantin v.kravtsov Alexander v.Syuy dmitry m.Tsymbarenko mikhail S.mironov Sergey m.Novikov Ivan kruglov davit A.ghazaryan Andrey A.vyshnevyy Aleksey v.Arsenin valentyn S.volkov kostya S.Novoselov moscow Center for Advanced Studies Kulakova str.20Moscow 123592Russia. emerging Technologies Research Center XPANCEOInternet CityEmmay TowerDubaiUnited Arab Emirates. donostia International physics Center(dIpC) Donostia/San-Sebastián 20018Spain. Institute of materials Ecole Polytechnique Federale de Lausanne1015 LausanneSwitzerland. department of Chemistry Lomonosov Moscow State UniversityMoscow 119991Russia. Laboratory of Advanced Functional materials Yerevan State UniversityYerevan 0025Armenia. National graphene Institute(NgI) University of ManchesterManchester M139PLUK. department of materials Science and engineering National University of SingaporeSingapore 03-09 EASingapore. Institute for Functional Intelligent materials National University of Singapore117544 SingaporeSingapore

The emergence of van der Waals(vdW)materials resulted in the discovery of their high optical,mechanical,and electronic anisotropic properties,immediately enabling countless novel phenomena and *** success inspired an intensive search for the highest possible anisotropic properties among vdW ***,the identification of the most promising among the huge family of vdW materials is a challenging quest requiring innovative ***,we suggest an easy-to-use method for such a survey based on the crystallographic geometrical perspective of vdW materials followed by their optical *** our approach,we found As2S3 as a highly anisotropic vdW *** demonstrates high in-plane optical anisotropy that is~20%larger than for rutile and over two times as large as calcite,high refractive index,and transparency in the visible range,overcoming the century-long record set by *** these benefits,As2S3 opens a pathway towards nextgeneration nanophotonics as demonstrated by an ultrathin true zero-order quarter-wave plate that combines classical and the Fabry–pérot optical phase ***,our approach provides an effective and easy-to-use method to find vdW materials with the utmost anisotropic properties.

关键词： anisotropy anisotropic high

Hydroxyapatite composites with carbon allotropes:preparation,properties,and applications

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particuology 2024年第5期88卷 239-265页

作者： Boris I.kharisov Oxana v.kharissova Lucy T.gonzález yolanda peña méndez Igor e.Uflyand Idalia gómez de la Fuente Universidad Autónoma de Nuevo León Ave.UniversidadCiudad UniversitariaSan Nicolás de los GarzaNuevo León 66455Mexico Tecnologico de monterrey Escuela de Ingeniería y CienciasMonterreyNuevo Leon 64890Mexico department of Chemistry Southern Federal UniversityRostov-on-DonRussia

Hydroxyapatite(HA)and its composites with inorganic additives,dopants,and polymers is a rapidly developing branch in the materials *** particular,carbon allotropes are widely used in these composites being widely applied for medical *** a gap of insufficient generalization of recent achievements in the field of the HA/Carbon composites,in this review we present the state of the art of the field of HA composites and hybrids with classic carbon allotropes and *** composites are known for carbon nanotubes,nanofibers,graphene and its oxidized forms,as well as,in a lesser grade,for graphite,fullerenes,nanodiamonds,carbon nanofoams,*** composites can be fabricated by a variety of classic and less-common methods,such as co-precipitation(with or without ultrasonic treatment),Cvd,hot isostatic pressing,hydrothermal,spark plasma sintering,biomimetic mineralization,thermal and plasma spray,electrochemical and electrophoretic deposition,self-assembling,3d printing,electrospinning,and lyophilisation,among *** of various synthesis techniques can be also carried out for composite *** or synthetic HA can be used as it is for further interaction with carbon allotropes or it can be first prepared and then reacted with carbon counterpart;similarly,carbon allotropes can be introduced into the interaction with HA directly or they can be first synthesized,in particular from *** biocompatible composites can be produced in the form of coatings,powders,and scaffolds and can additionally contain quantitative amounts of third phases,frequently natural or synthetic *** these composites,especially with O-containing functionalizing groups,HA disadvantages could be considerably decreased with simultaneous enhancement of mechanical properties,becoming similar to human bone,chemical stability and biocompatibility,as well as possessing antibacterial ***→g reduction and higher HA decoration were obs

关键词： Hydroxyapatite Carbon nanotubes graphene Quantum dots Fullerenes Nanodiamonds