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Temperature dependence of the liquid eutectic lead-lithium alloy density

广东有色金属学报 2005年第2期15卷 192-195页

作者： Alchag.rov Boris B. mozgovoi alexandr g. Taova Tamara M. Kabardino-Balkarian State University Nalchik 360004 Russia Joint Institute for Hig. Temperatures of

Lead-lithium alloys are of g.eat interest for practice as the advanced materials to be used in new technique, nuclear energ.tics, and so forth. Terefore, study on the physico-chemical properties of the latter is of major sig.ificance. An analysis of the available literature shows that there are a few works, devoted to study of Pb-Li alloys densities. However, temperature dependence of the density ρ(T), and its temperature coefficientK=dρ/dT for eutectic alloy were obtained by either extrapolation of the density data up to the eutectic alloy's composition, or calculation method. There is a certain discrepancy amounting.to as hig. as 4%, while the allowable error in the density measurements is less than 0.5%. The discrepancy between the results for the temperature coefficients of density amounts to 80%.In this work we present the experimental data on the temperature dependence of Ph0.83 Li0.17 eutectic alloy's density in the temperature rang. 520K to 643 K. The alloys were prepared using.Pb and Li with 99. 999% and 99.8% contents of the basic elements, respectively. We use the improved device, which permits to g.t the results with error less than 0. 15%. The results of 115 measurements of density in 520K to 643K temperature rang. were processed by the least-square method. Density polytherm of Pb0.83 Li0. 17 eutectic alloy is described by linear equation ρ(T) =9507.89-0. 79813(T-508) , kg.m3 ,where T is the absolute temperature by K. Mearsurement error was 0. 12% at 95% *** in the temperature coefficient data was 1.08%.Thus, the temperature dependence of the Pb-Li eutectic alloy density was studied by the precise two-capillary method. The obtained results may be recommended as the most reliable reference data.

关键词：锂合金温度化学活性金属组织

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Radiation of a TM mode from an open end of a three-layer dielectric capillary

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Chinese Physics B 2024年第7期33卷 311-318页

作者： Serg.y Ng.lyamin alexandr MAltmark St.Petersburg.State University 7/9Universitetskayanab.St.Petersburg 199034Russia St.Petersburg.Electrotechnical University“LETI” 5ProfessoraPopovaSt.Petersburg 197022Russia

Modern trends in beam-driven radiation sources include the interaction of Cherenkov wakefields in open-ended circular waveg.ides with complicated dielectric lining., with a three-layer dielectric capillary recently proposed to reduce radiation diverg.nce being.a representative example [Opt. Lett. 45 5416(2020)]. We present a rig.rous approach that allows for an analytical description of the electromag.etic processes that occur when the structure is excited by a sing.e waveg.ide TM mode. In other words, the corresponding.canonical waveg.ide diffraction problem is solved in a rig.rous formulation. This is a continuation of our previous papers which considered simpler cases with a homog.neous or two-layer dielectric filling. Here we use the same analytical approach based on the Wiener–Hopf–Fock technique and deal with the more complicated case of a three-layer dielectric lining. Using.the obtained rig.rous solution, we discuss the possibility of manipulating.the far-field radiation pattern using.a third layer made of a low permittivity material.

关键词： diffraction radiation open-ended waveg.ide Wiener–Hopf technique Cherenkov radiation

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Quantum alg.rithms for matrix operations and linear systems of equations

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Communications in Theoretical Physics 2024年第3期76卷 100-112页

作者： Wentao Qi alexandr I Zenchuk Asutosh Kumar Junde Wu School of Mathematical Sciences Zhejiang UniversityHangzhou 310027China Federal Research Center of Problems of Chemical Physics and Medicinal Chemistry RAS ChernogolovkaRussia P.g.Department of Physics Gaya CollegeMagadh UniversityRampurGaya 823001India Harish-Chandra Research Institute HBNIChhatnag RoadJhunsiPrayagraj 211019India Vaidic and Modern Physics Research Centre Bhagal BhimBhinmalJalore 343029India

Fundamental matrix operations and solving.linear systems of equations are ubiquitous in scientific *** the‘sender-receiver’model,we propose quantum alg.rithms for matrix operations such as matrix-vector product,matrix-matrix product,the sum of two matrices,and the calculation of determinant and inverse *** encode the matrix entries into the probability amplitudes of the pure initial states of *** applying.proper unitary transformation to the complete quantum system,the desired result can be found in certain blocks of the receiver’s density *** quantum protocols can be used as subroutines in other quantum ***,we present an alternative quantum alg.rithm for solving.linear systems of equations.

关键词： matrix operation systems of linear equations ‘sender-receiver’quantum computation model quantum alg.rithm

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A system-integ.ated approach for the desig. of tourist areas at the local level under chang.ng.conditions:A case study in the Altay Mountains

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Reg.onal Sustainability 2024年第2期5卷 89-102页

作者： alexandr Nikolaevich DUNETS Evg.niya Mikhailovna TABAKAEVA HAN Fang Department of Scientific and Innovative Development Altai State UniversityBarnaul656049Russia Department of Recreational g.og.aphy ServiceTourism and HospitalityInstitute of GeographyAltai State UniversityBarnaul656049Russia State Key Laboratory of Desert and Oasis Ecolog. Key Laboratory of Ecological Safety and Sustainable Development in Arid LandsXinjiang Institute of Ecology and GeographyChinese Academy of SciencesUrumqi830011China

The existing.approaches for the desig. of tourist areas often lead to limited flexibility in project *** realize a more flexible approach,in this study,we formulated a model for planning.and desig.ing.tourist areas at the local ***,specific tools for analyzing.tourist areas and ensuring.sustainable development under chang.ng.conditions were *** study was conducted in two tourist reg.ons,Biryuzovaya Katun tourist complex and Belokurikha destination(including.Belokurikha City with Belokurikha 2 g.rnaya tourist complex and surrounding.areas),in the Altay *** employed the recreation opportunity spectrum and proposed a system-integ.ated prog.amming.approach for the desig. of tourist areas at the destination and site *** key of this approach was the collection and analysis of current spatial data,including.the spatial distribution of attractions and visitor *** constructed heat maps using.video recording.and unmanned aerial vehicle(UAV)observation ***,we analyzed the video stream using.an imag.-analyzing.framework You Only Look Once(YOLO)v5 *** heat map of visitor flows based on video recording.data in the Andreevskaya Sloboda museum of Belokurikha 2 g.rnaya tourist complex allowed us to hig.lig.t the most attractive sites in this area and classify them into one of three types:points of functional concentration,points of transitional concentration,and points of *** heat maps in Biryuzovaya Katun tourist complex,created using.UAV observation data,allowed us to determine the spatiotemporal patterns of visitor flows and tourists’preferences throug.out the day within four time intervals:09:00-12:00,13:00-14:00,14:00-15:00,and 16:00-18:00(LST).The maximum visitor flow density occurred from 16:00 to 18:00 in the beach area of the artificial lake.A comparison between the visitor-concentrated sites and the current facilities provided insig.ts into the demand for attractions and facilities and

关键词： Tourism planning Tourist areas Unmanned aerial vehicle(UAV) Visitor flows Heat map Altay Mountains

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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 196-211页

作者： Mamatha Rani g. K.Sriram Deblina Lahiri Vijaya,A. Department of Astronomy Osmania UniversityHyderabad 500007India

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 P_(3)=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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Cu/TiO_(2) Photocatalysts for CO_(2) Reduction: Structure and Evolution of the Cocatalyst Active Form

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Transactions of Tianjin University 2024年第2期30卷 140-151页

作者： Andrey A.Saraev Anna Yu.Kurenkova Denis D.Mishchenko alexandr L.Trig.b Evg.niy Yu.g.rasimov Ekaterina A.Kozlova Boreskov Institute of Catalysis Lavrentieva Ave 5Novosibirsk 630090Russia Synchrotron Radiation Facility SKIF Boreskov Institute of CatalysisNikol’skiy Ave 1Kol’tsovo 630559Russia National Research Center “Kurchatov Institute”Kurchatova Sq 1Moscow 123182Russia

Extensive work on a Cu-modified TiO_(2) photocatalyst for CO_(2) reduction under visible lig.t irradiation was conducted. The structure of the copper cocatalyst was established using.UV-vis diff use refl ectance spectroscopy, hig.-resolution transmis- sion electron microscopy, X-ray absorption spectroscopy, and X-ray photoelectron spectroscopy. It was found that copper exists in different states (Cu 0 , Cu^(+) , and Cu^(2+) ), the content of which depends on the TiO_(2) calcination temperature and copper loading. The optimum composition of the cocatalyst has a photocatalyst based on TiO_(2) calcined at 700℃ and modified with 5 wt% copper, the activity of which is 22 μmol/(h·g.cat ) (409 nm). Analysis of the photocatalysts after the photocatalytic reaction disclosed that the copper metal on the surface of the calcined TiO_(2) was g.adually converted into Cu_(2) O during.the photocatalytic reaction. Meanwhile, the metallic copper on the surface of the noncalcined TiO_(2) did not underg. any trans- formation during.the reaction.

关键词： Photocatalysis Photocatalytic CO_(2)conversion Visible lig.t Titanium dioxide Copper Copper oxides Methane formation Photocatalyst transformation

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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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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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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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A Preliminary Comparative Study on the Centering.Alg.rithms for CassiniISS NAC Imag.s

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Research in Astronomy and Astrophysics 2024年第10期24卷 58-65页

作者： T.Liang.Q.-F.Zhang.g.-M.Liu W.-H.Zhu C.-S.Wang Department of Computer Science Jinan UniversityGuangzhou 510632China Sino-French Joint Laboratory for Astrometry Dynamics and Space ScienceJinan UniversityGuangzhou 510632China School of Computer Science Guangdong University of EducationGuangzhou 510303China

Obtaining.hig. precision is an important consideration for astrometric studies using.imag.s from the Narrow Ang.e Camera(NAC)of the Cassini Imag.ng.Science Subsystem(ISS).Selecting.the best centering.alg.rithm is key to enhancing.astrometric *** this study,we compared the accuracy of five centering.alg.rithms:g.ussian fitting.the modified moments method,and three point-spread function(PSF)fitting.methods(effective PSF(ePSF),PSFEx,and extended PSF(x PSF)from the Cassini Imag.ng.Central Laboratory for Operations(CICLOPS)).We assessed these alg.rithms using.70 ISS NAC star field imag.s taken with CL1 and CL2 filters across different stellar *** ePSF method consistently demonstrated the hig.est accuracy,achieving.precision below 0.03 pixels for stars of mag.itude *** to the previously considered best,the modified moments method,the e PSF method improved overall accuracy by about 10%and 21%in the sample and line directions,***,the xPSF model provided by CICLOPS had lower precision than the ***,the ePSF exhibits an improvement in measurement precision of 23%and 17%in the sample and line directions,respectively,over the *** discrepancy mig.t be attributed to the xPSF focusing.on photometry rather than *** finding. hig.lig.t the necessity of constructing.PSF models specifically tailored for astrometric purposes in NAC imag.s and provide g.idance for enhancing.astrometric measurements using.these ISS NAC imag.s.

关键词： methods:analytical techniques:imag. processing stars:imag.ng astrometry

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