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Metal organic Chemical vapour Deposited Thin Films of Cobalt oxide Prepared via Cobalt Acetylacetonate

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Journal of Materials Science & Technology 2009年第1期25卷 85-89页

作者： C.U. Mordi M.A. Eleruja B.A. Taleatu G.o. Egharevba A.v. Adedeji o.o. Akinwunmi B. olofinjana C. Jeynes E.o.B. Ajayi Department of Physics Obafemi Awolowo University Ile-Ife Nigeria Department of Chemistry Obafemi Awolowo University Ile-Ife Nigeria Department of Physics Auburn University Alabama United States Department of Electronics and Electrical Engineering University of Surrey Guildford Surrey GU2 7XH UK

The single solid source precursor, cobalt （Ⅱ） acetylacetonate was prepared and characterized by infrared spectroscopy. Thin films of cobalt oxide were deposited on soda lime glass substrates through the pyrolysis （metal organic chemical vapour deposition （MoCvD）） of single solid source precursor, cobalt acetylacetonate, Co[C5H7o2]2 at a temperature of 420℃. The compositional characterization carried out by rutherford backscattering spectroscopy and X-ray diffraction （XRD）, showed that the films have a stoichiometry of Co2o3 and an average thickness of 227±0.2 nm. A direct energy gap of 2,15±0.01 ev was calculated by the data obtained by optical absorption spectroscopy. The morphology of the films obtained by scanning electron microscopy, showed that the grains were continuous and uniformly distributed at various magnifications, while the average grain size was less than i micron for the deposited thin films of cobalt oxide.

关键词： Precursor Thin film oxide Metal organic chemical vapour deposition (MoCvD) Rutherford backscattering spectroscopy (RBS)

Peculiarities of the rheological behavior and structure formation of aluminum under deformation at near-solidus temperatures

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International Journal of Minerals,Metallurgy and Materials 2016年第5期23卷 563-571页

作者： A. S. Smirnov A. v. Konovalov G. A. Belozerov v. P. Shveikin E. o. Smirnova Institute of Engineering Science Russian Academy of Science (Ural Branch) 34 Komsomolskaya Street Ekaterinburg 620049 Russia Ural Federal University 19 Mira Street Ekaterinburg 620002 Russia

This paper deals with a peculiar rheological behavior of aluminum at near-solidus temperatures. It has been experimentally estab- lished that there is an inverse strain rate dependence of strain resistance at temperatures ranging between 560 and 640℃ and strain rates ranging from 0.06 to 1.2 s-1. Electron backscatter diffraction analysis has shown that at temperatures ranging between 540 and 640℃ and strain rates ranging from 0.06 to 0.1 s-1, the main process of softening is dynamic polygonization, resulting in in situ recrystallization. At higher strain rates, ranging between 0.8 and 1.2 s-1, and temperatures ranging between 560 and 640℃, the recovery is dynamic. This unusual behavior of the mechanism of softening and the presence of the inverse strain rate dependence of strain resistance can be explained by blocking the motion of free dislocations by foreign atoms, which occurs at strain rates ranging between 0.06 and 0.1 s-1 This process results in dislocation pile-up, thereby causing in sire recrystallization. At strain rates exceeding 0.16 s-1, there is no intensive blocking of dislocations, leading to a direct strain rate dependence of strain resistance.

关键词： aluminum rheological behavior formation near-solidus temperature

Sensitivity analysis and calibration of the Modified Universal Soil Loss Equation(MUSLE) for the upper Malewa Catchment,Kenya

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International Journal of Sediment Research 2013年第3期28卷 368-383页

作者： v.o.oDoNGo J.o.oNYANDo B.M.MUTUA P.R.van oEL R.BECHT University of Twente Faculty of Geoinformation Science&Earth Observation(ITC) Egerton University Department of Agricultural Engineering Wageningen University Water Resources Management Group

Simulation models are widely used for studying physical processes such as surface runoff,sediment transport and sediment yield in *** models need case-specific empirical data for parameterization before being applied especially in regions other than the ones they have been *** analysis is usually performed to determine the most influential factors of a model so that they can be prioritized for *** this way uncertainties in model outputs can be reduced *** study evaluates the commonly used modified universal soil loss equation(MUSLE) model used for sediment yield simulation for the case of the upper Malewa catchment in *** conceptual factors of the model are assessed relative to the hydrological factors in the ***,the sensitivity of the model to the choice of the objective function in calibration is *** Sobol’ sensitivity analysis method was used for evaluating the degree of sensitivity of the conceptual and hydrological factors for sediment yield simulations using the MUSLE ***-Sutcliffe Efficiency(NSE) and the modified Nash-Sutcliffe Efficiency(NSEm) are used to test the sensitivity of the model to the choice of the objective function and robustness of model performance with sediment data measured from upper Malewa catchment,*** results indicate that the conceptual factors are the most sensitive factors of the MUSLE model contributing about 66%of the variability in the output sediment *** variability of sediment yield output was also *** was attributed to interactions of input *** the upper Malewa catchment calibration of the MUSLE model indicates that the use of NSEm as an objective function provides stable results,which indicates that the model can satisfactorily be applied for sediment yield simulations.

关键词： MUSLE Sobol’sensitivity analysis Sediment yield objective function Upper Malewa catchment

Hypothalamic circuits and aging:keeping the circadian clock updated

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Neural Regeneration Research 2024年第9期19卷 1919-1928页

作者： Rosa vázquez-Lizarraga Lucia Mendoza-viveros Carolina Cid-Castro Sareni Ruiz-Montoya Erick Carreño-vázquez Ricardo orozco-Solis Instituto Nacional de Medicina Genómica(INMEGEN) México CityMéxico Centro de Investigacíon sobre el Envejecimiento Centro de Investigacíon y de Estudios Avanzados(CIE-CINVESTAV)México CityMéxico Instituto de Investigaciones Biomédicas Universidad Nacional Autónoma de México UNAMMéxico CityMéxico

over the past century,age-related diseases,such as cancer,type-2 diabetes,obesity,and mental illness,have shown a significant increase,negatively impacting overall quality of *** on aged animal models have unveiled a progressive discoordination at multiple regulatory levels,including transcriptional,translational,and post-translational processes,resulting from cellular stress and circadian *** circadian clock emerges as a key regulator,sustaining physiological homeostasis and promoting healthy aging through timely molecular coordination of pivotal cellular processes,such as stem-cell function,cellular stress responses,and inter-tissue communication,which become disrupted during *** the crucial role of hypothalamic circuits in regulating organismal physiology,metabolic control,sleep homeostasis,and circadian rhythms,and their dependence on these processes,strategies aimed at enhancing hypothalamic and circadian function,including pharmacological and non-pharmacological approaches,offer systemic benefits for healthy *** brain-directed drug administration represents a promising avenue for effectively targeting specific brain regions,like the hypothalamus,while reducing side effects associated with systemic drug delivery,thereby presenting new therapeutic possibilities for diverse age-related conditions.

关键词： aging astrocytes cellular stress responses circadian clock hypothalamus intranasal drug administration metabolic control nutrient sensor SIRT1 sleep homeostasis

Isomeric pair 95m,g Nb in the photonuclear reactions on natMo at the bremsstrahlung end-point energy of 38–93 Mev

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Chinese Physics C 2023年第12期47卷 64-72页

作者： I.S.Timchenko o.S.Deiev S.M.olejnik S.M.Potin v.A.Kushnir v.v.Mytrochenko S.A.Perezhogin v.A.Bocharov Institute of Physics Slovak Academy of SciencesSK-84511 BratislavaSlovakia National Science Center"Kharkov Institute of Physics and Technology" 1Akademichna St.61108KharkivUkraine CNRS/IJCLAB 15 Rue Georges Clemenceau Str.Orsay91400France

The ^(nat)Mo(γ,xnp)^(95m,g)Nb photonuclear reaction was studied using the electron beam from the NSC KIPT linear accelerator *** experiment was performed using the activation and off-line γ-ray spectrometric *** experimental isomeric yield ratio(IR) was determined for the reaction products ^(95m,g)Nb at the bremsstrahlung end-point energy E_(γmax) range of 38-93 *** obtained values of IR are in satisfactory agreement with the results of other studies and extend the range of previously known *** theoretical values of the yields Y_(m,g)(E_(γmax)) and the IR for the isomeric pair ^(95m,g)Nb from the ^(nat)Mo(γ,xnp) reaction were calculated using the partial cross-sections σ(E) from the TALYS1.95 code for six different level density *** the investigated range of E_(γmax),the theoretical dependence of IR on energy was confirmed-the IR smoothly increases with increasing *** comparison showed a noticeable difference(more than 3.85 times) in the experimental IR relative to all theoretical estimates.

关键词： photonuclear reactions natMo isomeric pair 95m gNb isomeric yield ratio reaction yield bremsstrahlung end-point energy of 38–93 Mev activation and off-lineγ-ray spectrometric technique TALYS1.95 level density model GEANT4.9.2.

Influence of the safety factor profile on the particle and heat transport in the Globus-M spherical tokamak

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Plasma Science and Technology 2019年第11期21卷 1-6页

作者： A YU TELNovA G S KURSKIEv E o KISELEv N N BAKHAREv v K GUSEv N A KHRoMov S YU MEDvEDEv v B MIINAEv I v MIRoSHNIKov M I PATRov Yu v PETRov N v SAKHARov A D SLADKoMEDovA P B SHCHEGoLEv v v SoLoKHA v A ToKAREv S YU ToLSTYAKov E A TUKHMENEvA Ioffe Institute Saint-Petersburg 194021Russia Keldysh Institute Russian Academy of SciencesMoscow 125047Russia NRC'Kurchatov Institute’ Moscow 123098Russia

The advanced tokamak scenario is a promising operation scenario for ITER and fusion neutron *** this scenario the minimum value of the safety factor in the center of the plasma exceeds *** the compact spherical tokamak Globus-M,the formation of such conditions is possible with neutral beam injection at the current ramp-up *** to the slower diffusion of current inside the plasma,a zone is formed with reduced heat and particle transport across the magnetic field,which affects the temperature and density profiles of the *** leads to the peaked density profile formation and improvement of the energy confinement *** achieve a high fraction of the bootstrap current,it is necessary to increase the plasma *** the same time,the maximum allowable pressure is limited to the normalized beta limit.

关键词： advanced tokamak mode transport analysis internal transport barriers

Highly Defective Dark Tio_(2) Modified with Pt: Effects of Precursor Nature and Preparation Method on Photocatalytic Properties

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Transactions of Tianjin University 2024年第2期30卷 198-209页

作者： E.D.Fakhrutdinova o.A.Reutova T.A.Bugrova I.Yu.ovsyuk L.S.Kibis o.A.Stonkus D.B.vasilchenko o.v.vodyankina v.A.Svetlychnyi National Research Tomsk State University TomskRussia 634050 Novosibirsk State University NovosibirskRussia 630090 Boreskov Institute of Catalysis NovosibirskRussia 630090 Nikolaev Institute of Inorganic Chemistry NovosibirskRussia 630090

The study focused on the modification with platinum of dark defective titania obtained via pulsed laser ablation. Both the method of Pt introduction and the nature of the Pt precursor were varied. All samples exhibited similar phase compositions, specific surface areas, and Pt contents. High-resolution transmission electron microscopy coupled with pulsed Co adsorption revealed increased dispersity when photoreduction and the hydroxonitrate complex (Me _(4) N) _(2) [Pt _(2) (oH) _(2) (No _(3) ) _(8) ] were used. The sample featured a high content of single-atom species and subnano-sized Pt clusters. The X-ray photoelectron spectroscopy results showed that the photoreduction method facilitated the appearance of a larger number of Pt ^(2+) states, which appeared owing to the strong metal-support interaction (SMSI) eff ect of the transfer of electron density from the electron-saturated defects on the Tio _(2) surface to Pt ^(4+) . In the hydrogen evolution reaction, samples with a significant fraction of the Pt ^(2+) ionic component, capable of generating short-lived Pt^(0) single-atom sites under irradiation due to the SMSI eff ect, exhibited the highest photocatalytic activity. The 0.5Pt(C)/Tio_(2) -Ph sample exhibited the highest hydrogen yield with a quantum efficiency of 0.53, retaining its activity even after 8 h of operation.

关键词： Dark(black)Tio_(2) Pulsed laser ablation Platinum reduction method Precursor type Photocatalysis Hydrogen evolution reaction

Analysis of TESS Field Eclipsing Binary Star v948 Her: A Pulsating or Non-pulsating Star?

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Research in Astronomy and Astrophysics 2022年第1期22卷 137-147页

作者： F Kahraman Alicavus o Ekinci Canakkde onsekiz Mart University Faculty of Sciences and ArtsPhysics Department17100QanakkaleTurkey Canakkale onsekiz Mart University Astrophysics Research Center and Ulupinar ObservatoryTR-17100CanakkaleTurkey Canakkale onsekiz Mart University School of Graduate StudiesDepartment of Space Sciences and TechnologiesTR-17100CanakkaleTurkey

Pulsating stars occupy a significant place in the H-R diagram and it was thought that all stars inside the classical instability strip should pulsate. However, recent studies showed that there are many non-pulsating stars located inside the classical instability strip. The existence of these non-pulsating stars is still a mystery. To deeply understand the properties of these non-pulsating and pulsating stars, one needs precise fundamental stellar parameters(e.g. mass).For this purpose, the eclipsing binaries are unique systems. Hence, in this study, we present the TESS data analysis of one candidate pulsating eclipsing binary system, v948 Her. TESS data were used for the binary modeling with the literature radial velocity measurements, and the precise fundamental parameters of the system were obtained. The system’s age was derived as 1 ± 0.24 Gyr. The positions of the binary components in the H-R diagram were examined and the primary component was found inside the δ Scuti instability strip. However, in the frequency analysis of TESS data, we found no significant pulsation frequencies. only the harmonics of the orbital periods were obtained in the analysis. Therefore, the system was classified as a non-pulsator. v948 Her is an important object to understand the nature of non-pulsating stars inside the δ Scuti instability strip.

关键词： (stars:)binaries:eclipsing stars:fundamental parameters techniques:photometric

Cluster Analysis of the Roma-BZCAT Blazars

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Research in Astronomy and Astrophysics 2024年第5期24卷 117-139页

作者： Dmitry o.Kudryavtsev Yulia v.Sotnikova vladislav A.Stolyarov Timur v.Mufakharov valery v.vlasyuk Margarita L.Khabibullina Alexander G.Mikhailov Yulia v.Cherepkova Special Astrophysical observatory of the Russian Academy of Sciences Nizhny Arkhyz 369167Russia Astrophysics Group Cavendish LaboratoryUniversity of CambridgeCambridge CB3 OHEUK Kazan Federal University 18 Kremlyovskaya StKazan 420008Russia

Based on the collected multiwavelength data, namely in the radio(NvSS, FIRST, RATAN-600), IR(WISE),optical(Pan-STARRS), Uv(GALEX), and X-ray(RoSAT, Swift-XRT) ranges, we have performed a cluster analysis for the blazars of the Roma-BZCAT catalog. Using two machine learning methods, namely a combination of PCA with k-means clustering and Kohonen's self-organizing maps(SoMs), we have constructed an independent classification of the blazars(five classes) and compared the classes with the known Roma-BZCAT classification(FSRQs, BL Lacs, galaxy-dominated BL Lacs, and blazars of an uncertain type) as well as with the high synchrotron peaked(HSP) blazars from the 3HSP catalog and blazars from the TevCat catalog. The obtained groups demonstrate concordance with the BL Lac/FSRQ classification along with a continuous character of the change in the properties. The group of HSP blazars stands out against the overall distribution. We examine the characteristics of the five groups and demonstrate distinctions in their spectral energy distribution shapes. The effectiveness of the clustering technique for objective analysis of multiparametric arrays of experimental data is demonstrated.

关键词： methods data analysis-galaxies active-(galaxies:)BL Lacertae objects general