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Chinese Journal of Polymer science 2024年第11期 1793-1801页

作者： e.e.Kim T.O.ershova A.s.Belova D.A.Khanin e.v.Bashkova G.G.Nikiforova Yu.N.Kononevich A.A.Anisimov O.I.shchegolikhina A.M.Muzafarov A.N.Nesmeyanov Institute of Organoelement Compounds Russian Academy of Sciences Tula state lev Tolstoy Pedagogical University v.Topchiev Institute of Petrochemical synthesis Russian Academy of sciences Moscow Institute of Physics and Technology (National Research University) N.s.enikolopov Institute of synthetic Polymeric Materials Russian Academy of Sciences

Nowadays organosilicon luminescent materials are of increasing interest due to the variety of their synthetic or modification techniques and application fields. ladder polyphenylsilsesquioxanes(l-PPsQ) are a unique class of organosilicon polymers, which can be ideal matrices for the luminescent composites due to their high thermal stability, optical transparency and mechanical strength. In this work, new mechanically strong, heat-resistant, transparent and sensitive to ammonia vapor luminescent composite films based on l-PPsQ have been obtained. As the source of europium ions oligophenyleuropiumsiloxane was used, demonstrating perfect compatibility to the matrix due to the similar *** improve luminescent properties of the films, new organosilicon ligands were introduced into the composites and their influence on the properties of the materials was studied. valuable properties of described composites may allow their further application as multifunctional coatings.

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Kinetics and mechanism of the low-energy b-a phase transition of the second kind in 2,4-dinitroanisole

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Defence Technology（防务技术） 2024年第10期40卷 210-224页

作者： Aleksandr v.stankevich Nikolay A.Rasputin Anisa KhRudina Gennady l.Rusinov vera I.Filyakova valery N.Charushin y1.postovsky institute of organic synthesis ural branch of the russian academy of sciencesekaterinburg 620108russia russian federal nuclear center e zababakhin all-russia research institute of technical physics snezhinsk 456770russia kazan national research technological university kazan 420015russia

In this work,comprehens.v. studies of 2,4-dinitroanisole(2,4DNAN)were carried out using powder thermorentgenography of the internal *** time of the complete polymorphic transition in the solid phase b/a in 2,4DNAN under various combinations of conditions has been *** has been established that,regardless of the season of manufacture of the substance,when it is stored for 8e9 months,with a change in ambient temperature from minus 30℃ to plus 30℃,a complete polymorphic transition b/a *** stored in conditions below minus 5℃,polymorphic transition does not *** stored in conditions above plus 30℃ in a closed container,polymorphic transition occurs within 3 *** polymorphic transition is accompanied by a decrease in density by 1.3%e1.5%and an increase in melting temperature by 10-12℃,depending on the degree of purity of the starting *** activation energy of the molecular rearrangement was 68e70 kJ/mol(16.5±3 kcal/mol).The mechanism of polymorphic transition has been evaluated,which is presumably based on internal homodiffusion and energy transfer to the surface of the mass of powder particles and the *** average activation energy of the polymorphic transition process was 110±6.2 kJ/mol(26.2 kcal/mol).In an open container,reactions proceed by a homogeneous mechanism,and in a closed container by a heterogeneous mechanism involving the gas phase.

关键词： energetic materials Melt-castable 2,4-Dinitroanisole Polymorphic transition Kinetics Mechanism Homodiffusion sublimation

Older Adult Compendium of Physical Activities:energy costs of human activities in adults aged 60 and older

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Journal of sport and Health science 2024年第1期13卷 13-17,F0003页

作者： erik A.Willis stephen D.Herrmann Mary Hastert Chelsea l.Kracht Tiago v.Barreira John M.schuna Jr. Zhenghua Cai Minghui Quan scott A.Conger Wendy J.Brown Barbara e.Ainsworth Center for Health Promotion and Disease Prevention University of North Carolina at Chapel HillChapel HillNC 27599USA Kansas Center for Metabolism and Obesity Research The University of Kansas Medical CenterKansas CityKS 66160USA Division of Physical Activity and Weight Management Department of Internal MedicineUniversity of Kansas Medical CenterKansas CityKS 66160USA Clinical science Division Pennington Biomedical Research CenterBaton RougeLA 70808USA exercise science Department Syracuse UniversitySyracuseNY 13244USA school of exercise&sport science Oregon State UniversityCorvallisOR 97331USA school of exercise and Health Shanghai University of SportShanghai 200438China Department of Kinesiology Boise State UniversityBoiseID 83725USA school of Human Movement and Nutrition sciences The University of QueenslandSt.LuciaQLD 4072Australia Faculty of Health sciences and Medicine Bond UniversityGold CoastQLD 4229Australia College of Health solutions Arizona State UniversityPhoenixAZ 85003USA

Purpose:To describe the development of a Compendium for estimating the energy costs of activities in adults>60 years(OA Compendium).Methods:Physical activities(PAs)and their metabolic equivalent of task(MeT)values were obtained from a systematic search of studies published in 4 sport and exercise databases(PubMed,embase,sPORTDiscus(eBsCOhost),and scopus)and a review of articles included in the 2011 Adult Compendium that measured PA in older *** values were computed as the oxygen cost(vO_(2),ml/kg/min)during PA divided by 2.7 m l/kg/min(MeT_(60+))to account for the lower resting metabolic rate in older ***:We identified 68 articles and extracted energy expenditure data on 427 *** these,we derived 99 unique specific Activity codes with corresponding MeT_(60+)values for older *** developed a website to present the OA Compendium MeT_(60+)values:https://***:The OA Compendium uses data collected from adults>60 years for more accurate estimation of the energy cost of PAs in older *** is an accessible resource that will allow researchers,educators,and practitioners to find MeT_(60+)values for older adults for use in PA research and practice.

关键词： energy expenditure exercise MeT Older adults

Unveiling the atomic-scale transition between light harvesting and photoprotective states in plant photosynthesis

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science China Chemistry 2024年第5期67卷 1375-1377页

作者： Alexander v.Ruban school of Biological and Behavioural sciences Queen Mary University of LondonLondon E14NSUK

Non-photochemical chlorophyll fluorescence quenching(NPQ) stands as a cornerstone in the realm of photosynthesis research, attracting generations of dedicated scientists in their quest to unravel its mysteries. This mechanism, crucial for safeguarding photosynthesis, plays a pivotal role in regulating light harvesting, particularly in oxygenic photosynthesis where the oxygen-evolving photosystem II (PsII)is susceptible to photodamage [1].

关键词： harvesting protective attracting

3,6-Bis-β-Dicarbonylsubstituted Carbazoles Bearing N-spacers and Their eu(III) Complexes as Immunofluorescent labelling Agents

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International Journal of Organic Chemistry 2024年第1期14卷 20-31页

作者： Dmitry e. Pugachev Georgy v. Zatonsky Tatyana s. Kostryukova Anna G. shubina Nikolay v. vasiliev Department of Biological Microanalysis FGUP State Research Institute of Biological Engineering Moscow Russia Department of Theoretical and Applied Chemistry State University of Education Mytishchi Russia

New reagents for immunofluorescence analysis of carbazole series containing fluorinated β-dicarbonyl fragments and carboxylic substituent groups separated by spacers of different lengths from the light-gathering carbazole scaffold have been developed. The markers in complex with eusup>3+sup> ions possess stability in the aqueous phase, intense and prolonged luminescence (τ 550 - 570 μs) with characteristic emission maxima in the region of 615 nm and excitation wavelengths in the region of 380 - 390 nm, which distinguishes them from most of the analogs used. In the study of marker conjugation with streptavidin, a reagent containing 4 - 5 europium labeling complexes based on spacer-containing carbazole tetraketone was obtained. The marker-doped silicate nanoparticles exhibit intense and long-lived luminescence in the characteristic region.

关键词： Fluorescence Immunoassay Fluorinated β-Diketones Carbazole europium Complexes streptavidin Nanodispersions

Assessment of sediment connectivity using modelling and field-based approaches in the slavíč River catchment(MoravskoslezskéBeskydy Mts,Czech Republic)

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Journal of Mountain science 2024年第3期21卷 734-753页

作者： MACUROvÁ Tereza ŠKARPICH václav Department of Physical Geography and Geoecology Faculty of ScienceUniversity of OstravaChittussiho 1071000 OstravaCzech Republic

Mountain streams act as conveyors of sediments within the river continuum,where the physical transport of sediments between river reaches through the catchment or between individual parts(e.g.,between hillslopes and channels)of the catchment is *** study focused on sediment connectivity analysis in the slavíčRiver catchment in the MoravskoslezskéBeskydy Mts in the eastern part of the Czech *** connectivity index and connectivity index target modelling were combined with an analysis of anthropogenic ***,field mapping,grain size of bed sediments and stream power analysis were used to obtain information about connectivity in the *** on the analysis and obtained results,terrain topography is the current main driving factor affecting the connectivity of sediment movement in the slavíčRiver ***,the modelling provided valuable information about high sediment connectivity despite different recent land use conditions(highly forested area of the catchment)than those in historical times from the 16th to 19th centuries when the slavíčRiver catchment was highly deforested and sediment connectivity was probably *** analysis of anthropogenic interventions,field mapping,grain size of bed sediments and stream power analysis revealed more deceleration of sediment movement through the catchment,decreased sediment connectivity with bed erosion,and gradual river channel process transformation in some *** mapping has identified various natural formations and human-induced changes impacting the longitudinal and lateral connectivity in the slavíč*** instance,embankments along 48%of the river's length,both on the right and left banks,significantly hinder lateral sediment supply to the *** power index analysis indicates increased energy levels in the flowing water in the river's upper reaches(up to 404.8 W m^(-2)).This high energy is also observed in certain downstream sections(up to 337.6 W

关键词： Mountain stream Connectivity analysis Modelling Grain size analysis slavíčRiver MoravskoslezskéBeskydy Mts

BaTiO_(3)solid solutions co-doped with Gd^(3+)and eu^(3+):synthesis,structural evolution and dielectric properties

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Journal of Rare earths 2024年第10期42卷 1920-1926页

作者： R.Martínez-lópez M.Pérez-labra J.A.Romero-serrano F.R.Barrientos-Hernández M.Reyes-Pérez M.I.valenzuela-Carrillo G.Urbano-Reyes.v.e.Reyes-Cruz G.I.Dávila-Pulido Academic Area of earth sciences and Materials Autonomous University of Hidalgo StateRoad Pachuca-Tulancingo Km 4.5 Mineral de La Reforma.Hidalgo42184Mexico Metallurgy and Materials Department ESIQIE-IPNUPALMZacatencoCiudad de Mexico07738Mexico Autonomous University of Coahuila Boulevard Adolfo López Mateos S/nNueva RositaCoahuila26800Mexico

In this paper,the synthesis,structural evolution,and dielectric properties of BaTiO_(3)solid solutions codoped with rare earth elements(Gd^(3+)and eu^(3+))prepared using the solid-state reaction method are *** pure precursor powders of BaCl_3,TiO_(2),Gd_(2)O_(3),and eu_(2)O_(3)were mixed in stoichiometric proportions,ground in an agate mortar before being uniaxially pressed at 250 MPa and sintered at 1300℃in air atmosphere for 6 h to obtain Ba_(1-3x)Gd_(2x)Ti_(1-3x)eu_(4x)O_(3)(x=0,0.0015,0.01 and0.1).X-ray diffraction(XRD)and Rietveld's refinement results reveal the crystal phase ferroelectric tetragonal BaTiO_(3)for the samples with x=0,0.0015 and 0.01,as well as a consistent increment in the lattice parameters caused by the *** solubility limit of Gd^(3+)and eu^(3+)in the BaTiO_(3)structure is reached for the sample with x>0.01,and the orthorhombic eu_2TiO_(5)and monoclinic BaTi_(2)O_(5)secondary phases were *** Raman results show the characteristic peaks of ferroelectric tetragonal BaTiO_(3)around 716 cm^(-1)(lO of A1 symmetry),515 cm^(-1)(TO of A1 symmetry),and 305 cm^(-1)(B1).The maximum relative permittivity measured at 1 kHz was recorded to be 6151.8 for the sample with x=0.0015,and a decrease in the Curie temperature to 105℃with respect to the undoped sample was *** punctual microanalysis for the samples with x=0.0015,0.01,and 0.1 reveals grains composed of Ba,Ti,O,Gd,and eu homogeneously distributed in the BaTiO_(3)*** Ba/Ti ratios for samples with x=0.0015,0.01 and 0.1 are 2.86,2.91,and 0.68,respectively,indicating substitution at the Ti site for samples with x=0.0015 and 0.01 and a substitution at the Ba site for the sample with x=0.1.

关键词： BaTiO_(3) Doping Gadolinium europium synthesis Rare earths

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.Kharis.v.Oxana v.Khariss.v. 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

Boosting propane dehydrogenation by gallium hydride species formed in situ

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science China Chemistry 2024年第6期67卷 1753-1755页

作者： evgenii v.Kondratenko leibniz-Institut für Katalyse e.v. Albert-Einstein-Str.29aRostock18059Germany

An inspiring paper recently published in Nature Chemistry[1]by the group of *** Gong at Tianjin University is the motivation for this highlight *** reported results show that the understanding of reaction-induced restructuring of heterogeneous catalysts is of great importance for their targeted development because usually unstable compounds can be formed and stabilized under reaction conditions.

关键词： conditions hydride stabilized

2024 Adult Compendium of Physical Activities:A third update of the energy costs of human activities

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Journal of sport and Health science 2024年第1期13卷 6-12页

作者： stephen D.Herrmann erik A.Willis Barbara e.Ainsworth Tiago v.Barreira Mary Hastert Chelsea l.Kracht John M.schuna Jr. Zhenghui Cai Minghui Quan Catrine Tudor-locke Melicia C.Whitt-Glover David R. Jacobs Jr. Kansas Center for Metabolism and Obesity Research University of Kansas Medical CenterKansas CityKS 66160USA Division of Physical Activity and Weight Management Department of Internal MedicineUniversity of Kansas Medical CenterKansas CityKS 66160USA Center for Health Promotion and Disease Prevention University of North Carolina at Chapel HillChapel HillNC 27599USA College of Health solutions Arizona State UniversityPhoenixAZ 85003USA school of exercise and Health Shanghai University of SportShanghai 200438China exercise science Department Syracuse UniversitySyracuseNY 13244USA Clinical sciences Division Pennington Biomedical Research CenterBaton RougeLA 70808USA school of exercise and sport science Oregon State UniversityCorvallisOR 97331USA College of Health and Human services University of North Carolina at CharlotteCharlotteNC 28223USA Gramercy Research Group KnightdaleNC 27545USA Division of epidemiology and Community Health School of Public HealthUniversity of MinnesotaMinneapolisMN 55454USA

Background:The Compendium of Physical Activities was published in 1993 to improve the comparability of energy expenditure values assigned to self-reported physical activity(PA)across *** original version was updated in 2000,and again in 2011,and has been widely used to support PA research,practice,and public health ***:This 2024 update was tailored for adults 19-59 years of age by removing data from those≥60 *** a systematic review and supplementary searches,we identified new activities and their associated measured metabolic equivalent(MeT)values(using indirect calorimetry)published since *** replaced estimated MeTs with measured values when ***:We screened 32,173 abstracts and 1507 full-text papers and extracted 2356 PA energy expenditure values from 701 *** added303 new PAs and adjusted 176 existing MeT values and descriptions to reflect the addition of new data and removal of MeTs for older *** added a Major Heading(video Games).The 2024 Adult Compendium includes 1114 PAs(912 with measured and 202 with estimated values)across 22 Major ***:This comprehens.v. update and refinement led to the creation of The 2024 Adult Compendium,which has utility across research,public health,education,and healthcare domains,as well as in the development of consumer health *** new website with the complete lists of PAs and supporting resources is available at https://***.

关键词： Adults energy expenditure exercise MeT Physical Activities