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Enhanced saturation magnetization in La^(3+) doped NiCo ferrites prepared by sol-gel auto-combustion method

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Journal of Rare Earths 2024年第8期42卷 1546-1554,I0005页

作者： Maddileti Jelli vidyasagar Thopudurthy Krishna Reddy C.v. Department of Physics Rayalaseema UniversityKurnoolA.P518007.Iindia Department of Physics Government PolytechnicRayachotiA.P516269India

Lanthanum doped nickel-cobalt nano ferrites with chemical formula Ni_(0.5)Co_(0.5)LaxFe_(2-x)O_(4)(x=0.05,0,10,0.15 and 0,20) were prepared using a simple sol-gel auto combustion *** basic structural properties were determined by x-ray diffraction method and the formation of single phased spinel ferrite was *** crystalline size decreased from 25 to 11 nm and lattice parameter a increases with increase of La *** surface morphology of these ferrites was observed by field-emission scanning electron microscopy(FESEM) and agglomerated irregular grains are observed with increase of the rare earth element La ***-dispersive x-ray spectroscopy(EDx) result confirms the presence of the required *** Fourier transform infrared spectroscopy(FTIR) spectrum indicates the formation of the spinel ferrite structure with M-O *** direct band measurements from ultraviolet-visible spectroscopy(Uv-vis) spectroscopy indicate that the direct band gap decreases from 1.39 to 1.19 ev for x=0.05 to x=0.15,then increases to 1.28 ev for x=*** room temperature magnetic properties of these ferrites were studied by a vibrating sample magnetometer(vSM).The enhanced saturation magnetization of 49.73 emu/g is observed for x=0.10 and then saturation magnetizations are gradually decreased for x=0.15 and x=*** the remanent magnetization and coercivity also follow the same trend.

关键词： Ferrites Sol-gel auto combustion La doping Magnetic properties Rare earths

Wormhole solutions under the effect of dark matter in f(R,L_(m))gravity

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Communications in Theoretical Physics 2024年第5期76卷 102-113页

作者： Lakhan v Jaybhaye Moreshwar Tayde PK Sahoo Department of Mathematics Birla Institute of Technology and Science-PilaniHyderabad CampusHyderabad-500078India

In the background of f(R,L_(m))gravity,this work investigates three distinct dark matter halo profiles to test the possibility of generalised wormhole geometry within the galactic halo *** current study aims to accomplish these goals by examining various dark matter profiles including universal rotation curves(URC),Navarro-Frenk-White(NFW)model-Ⅰ,and NFW model-Ⅱinside two distinct f(R,L_(m))gravity *** to the f(R,L_(m))=R/2+L^(a)_(m)model,the dark matter(DM)halo density profiles produce suitable shape functions that meet all the necessary requirements for exhibiting the wormhole geometries with appropriate choice of free *** addition,to examine DM profiles under the f(R,L_(m))=R/2+(1+λR)L_(m) model,we consider a specific shape ***,we observed that the derived solution from both two models violates the null energy constraints,confirming that the DM supports wormholes to maintain in the galactic halo.

关键词： f(R L_(m))gravity wormhole dark matter(Some figures may appear in colour only in the online journal)

Clinical validation of the early embryo viability assessment system: Analysis for the blastocyst morphology and pregnancy outcomes

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Asian pacific Journal of Reproduction 2024年第5期13卷 219-227页

作者： vu D Hop An M Cuong Phi T T Anh Nguyen T L Huong le Hoang Nguyen v Hanh Assisted Reproductive Technology Centre Tam Anh General HospitalHanoiVietnam Institute of Biotechnology Vietnam Academy of Science and TechnologyHanoiVietnam

Objective:To determine the relationship between the early embryo viability assessment(EEvA)and blastocyst morphological parameters and pregnancy ***:This retrospective cohort study was conducted on 291 intracytoplasmic sperm injection cycles including 2522 embryos with indications of prolonging embryo culture to the blastocyst stage in the Genea embryo review incubator,and 511 single vitrified-warmed blastocyst transfer cycles from January 2020 to June *** EEvA system produced an EEvA score from E1(best)to E5(worse)for the potential of blastocyst *** morphology was *** association between the EEvA score and each type of blastocyst morphology,implantation rate,clinical pregnancy,and ongoing pregnancy were assessed using generalized estimating ***:The inner cell mass A(ICM A),trophectoderm A(TE A),blastocoele expansion degree of 3,4,5,6,7 rates were higher with lower the EEvA *** adjusted odd ratio(aOR)(E5 vs E1)was 0.3 for ICM A,0.174 for TE A and 0.210 for BL3,4,5,6,7(all PvA scores and improved embryo *** implantation,clinical pregnancy,and ongoing pregnancy rate were also higher with lower the EEvA *** aOR of E5 vs E1 was 0.245 for implantation,0.185 for clinical pregnancy and 0.200 for ongoing pregnancy rate(PvA *** good blastocyst morphology and pregnancy outcomes are higher with lower the EEvA score.

关键词： Automated embryo assessment Blastocyst Early embryo viability assessment Genea embryo review incubator

Thermo-and pH-sensitive Polymer with Pendant Spacer-linked Imidazole Cycles

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Chinese Journal of Polymer Science 2024年第4期42卷 437-445页

作者： Natalya v.Zakharova Stanislav N.Zelinskiy Mariya S.Strelova Elena N.Danilovtseva vadim v.Annenkov Institute of Macromolecular Compounds of the Russian Academy of Sciences Saint Petersburg199004Russia Limnological Institute of Siberian Branch of the Russian Academy of Sciences Irkutsk664033Russia

By the reaction of poly(acryloyl chloride) with N-(3-aminopropyl)imidazole, poly(N-(3-(1H-imidazol-1-yl)propyl)acrylamide) was synthesized. The new polymer contains an imidazole ring removed from the main chain by a spacer of five bonds. The structure and purity, molecular weight, hydrodynamic and thermosensitive properties of the obtained sample were studied by1H-and13C-NMR, FTIR spectroscopy, acid-base titration, light scattering, turbidimetry and viscometry. The observed ability of the imidazole-containing polymer to form and destroy associates in water-salt solutions at pH 6.6-7.4 and temperatures of 29-48℃ indicates that these are promising candidates for designing complex biomedical systems. The new polymer is able to form complexes with oligo-DNA more actively than poly(1-vinylimidazole), which is of interest for gene delivery applications. The polymer cross-linked with epichlorohydrin gives micro-relief coatings on the plastic surface, and the modified surface is able to attach negatively charged objects. This thermo-and pH-sensitive polymer modification can be applied to create finely controlled surfaces for cell culturing.

关键词： Imidazole-containing polymer Thermolability pH-sensitivity The modified surface DNA immobilization

Polyoxometalates-derived ternary metal oxides electrocatalyst for N_(2) reduction under ambient conditions

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Tungsten 2024年第2期6卷 428-437页

作者： Meng-le Yang Zhong-xin Jin xi-xian Cao xin-Ming Wang Hui-Yuan Ma Hai-Jun Pang Gui-xin Yang The School of Material Science and Chemical Engineering Harbin University of Science and TechnologyHarbin 150040China

Accelerating the breaking of the nitrogen nonpolar bond(N≡N)is an important factor to improve the effi ciency of the electro-catalytic nitrogen reduction reaction(e-NRR).In this work,polyoxometalates-derived FeMo-based ternary oxide materials MoO_(2)-Mo_(4)O_(11)-FeMoO_(4)@x(abbreviated as MoFeO@x,x represents the synthesis temperature of 650,750 and 850℃)were designed and synthesized for e-NRR under ambient *** scanning electron microscopy images of MoFeO@750 show an ellipsoidal-like structure(0.86×0.6μm).The relatively large specifi c surface area,formation of multiple interfaces,together with the synergistic eff ect of iron and molybdenum bimetals,would make MoFeO@x catalyst more easily absorb and activate N_(2)in the ***,the synthesized MoFeO@750 shows an optimal NH_(3)production rate of 16.57μg·h^(−1)·mg cat.^(−1)and Faradaic effi ciency of 12.33%at−0.3 v versus reversible hydrogen electrode(ν***),with outstanding electrochemical and structural stability.

关键词： Polyoxometalates Electrocatalytic nitrogen reduction reaction Ternary oxide Electrocatalyst

Exploring the potential of drill cuttings for reservoir characterization:A case study from the volga-Ural basin,Russia

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Petroleum Research 2024年第2期9卷 193-205页

作者： Ibrahem Yousef v.P.Morozov Kazan Federal University Institute of Geology and Petroleum Technologies420008Russian Federation

The research objectives are to assess the possibility of using drill cutting analysis to obtain information about the mineralogical and geochemical properties of the reservoir *** cutting samples were collected from a vertical well that penetrated the Domanik sediments(Semiluksk Formation)in one of the oil fields in the volga-Ural petroleum *** sections from drill cuttings were examined using an optical polarizing microscope(Axio Imager A2).x-ray diffraction(xRD)analyses were performed using a Brucker D2 Phaser x-ray powder *** properties were studied using an STA 449 F3 Jupiter *** pyrolytic studies were performed using the Rock-Eval *** inspection showed that the studied sediments are alternations of carbonates and siliceous-carbonate *** section examinations revealed that the carbonates are mainly limestone(mudstone and wackestone)and are characterized by a dense texture and up to 30%organic *** siliceous-carbonate rocks are dominated by siliceous mudstones and are characterized by dark colours,layered structure,and an enrichment in organic *** analyses showed that the carbonate rocks are mainly composed of calcite,dolomite,quartz,feldspar,and mica,which are minor *** siliceous-carbonate rocks are dominated by quartz,followed by calcite,although they also contain feldspars,mica,dolomite,and pyrite as *** to the simultaneous thermal analysis,the average total hydrocarbon in the carbonate and siliceous-carbonate rocks is 13.6%(for the core samples)and 11.5%(for the drill cutting samples).The content of heavy hydrocarbons in the rocks is higher than the content of light hydrocarbons,indicating the immature nature of organic *** is found sporadically in siliceous-carbonate *** to the pyrolytic studies,average S1 is 4.4 mg/g and average S2 is 19.8 mg/g(for the core samples);average S1 is 2.1 mg/g and average S2 is 17.8 mg/g(for the

关键词： Drill cuttings Reservoir characterization Domanik Semiluksk volga-Ural Russia

Energy band modulation of N-doped rutile/anatase TiO_(2) photoanode promoting charge separation toward prominent photoelectrochemical performance

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Rare Metals 2024年第8期43卷 3784-3797页

作者： Juan Gao Shi-xuan Wang Jia-le Deng Ping-Ping Wei Fu-Zhang Chen Ling-Cheng Zheng Yue-Qin Wang Yang Li Yin Liu Gang He School of Mechanics and Photoelectric Physics Anhui University of Science and TechnologyHuainan 232001China School of Materials Science and Engineering Anhui UniversityHefei230039China Tianneng Battery(Wuhu)Co. Ltd.Wuhu 241000China School of Materials Science and Engineering Anhui University of Science and TechnologyHuainan 232001China

To solve the problem of high photogenerated carrier recombination rate and low photoelectric conversion efficiency of TiO_(2)-based materials,a simple N-doped anatase/rutile TiO_(2) heterophase nanorod film was designed by a low-temperature hydrothermal method in this *** enhanced separation and transport of photogenerated charges were facilitated by the smaller contact barrier and appropriate band matching between anatase TiO_(2)nanoparticles and rutile TiO_(2) *** introduction of N doping in anatase TiO_(2) resulted in an upward shift of the valence band and a narrowing of the band gap,consequently enhancing the efficiency of visible light *** combination of the heterophase junction and N-doping exhibited a synergistic effect,effectively suppressing the recombination of photogenerated charges and enhancing the photoelectric conversion efficiency of the *** AM 1.5G irradiation,the photocurrent density(J)of the A-TO(N)@R-TONR photoanode reached2.19 mA·cm^(-2)(v_(RHE,1.23 ev)).Additionally,the incident photon-electron conversion efficiency(IPCE)and the charge injection efficiency(η)reached 81.4%and 51.6%at320 ***,the J,IPCE,andηvalues of the A-TO(N)@R-TONR photoanode were 2.96,2.1 and 3.2times those of pure R-TONR photoanode,*** work presents a rational strategy for designing efficient TiO_(2)-based photoanodes.

关键词： TiO_(2) Heterophase junction Photoanode

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Nonlinear-Optical Analogies in Nuclear-Like Soliton Reactions:Selection Rules,Nonlinear Tunneling and Sub-Barrier Fusion–Fission

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Chinese Physics letters 2024年第8期41卷 1-7页

作者： T.L.Belyaeva v.N.Serkin Universidad Autonoma del Estado de Mexico Av.Instituto Literario 100C.P.50000TolucaMexico Benemerita Universidad Autonoma de Puebla Av.4 Sur 104C.P.72001PueblaMexico

The main goal of our study is to reveal unexpected but intriguing analogies arising between optical solitons and nuclear physics,which still remain hidden from *** consider the main cornerstones of the concept of nonlinear optics of nuclear reactions and the well-dressed repulsive-core *** the base of this model,we reveal the most intriguing properties of the nonlinear tunneling of nucleus-like solitons and the soliton selfinduced sub-barrier transparency *** describe novel interesting and stimulating analogies between the interaction of nucleus-like solitons on the repulsive barrier and nuclear sub-barrier *** main finding of this study concerns the conservation of total number of nucleons(or the baryon number)in nuclear-like soliton *** show that inelastic interactions among well-dressed repulsive-core solitons arise only when a“cloud”of“dressing”spectral side-bands appears in the frequency spectra of the *** property of nucleus-like solitons is directly related to the nuclear density distribution described by the dimensionless small shape-squareness *** the Fourier spectra of nucleus-like solitons are similar to the nuclear form *** show that the nuclear-like reactions between well-dressed solitons are realized by“exchange”between“particle-like”side bands in their spectra.

关键词： solitons soliton Nonlinear

Morphology of crater and caldera lakes in the Far Eastern region of Russia and the features of their development

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Journal of Mountain Science 2024年第4期21卷 1246-1258页

作者： Dmitrii N.KOZLOv Ekaterina v.leBEDEvA Institute of Marine Geology and Geophysics Far Eastern Branch of the Russian Academy of SciencesYuzhno-Sakhalinsk 693022Russia Institute of Geography Russian Academy of SciencesMoscow 119017Russia

volcanic lakes in the Kuril-Kamchatka region are difficult to access,and for this reason,they remain poorly studied,with only scattered and brief data *** authors have conducted a study of 10 lake basins using modern digital echolocation survey techniques and have also compiled and summarized published data for 15 lakes in the region,calculating their main morphometric *** has been established that many caldera lake basins are modified by young explosive funnels,extrusive or effusive domes,and exhibit traces of hydrothermal *** lakes of the same genetic type in the Kuril-Kamchatka region are similar in depth and depression forms,the group of caldera lakes shows less homogeneity across all morphometric *** was found that the absolute heights of the reservoirs on Kamchatka Peninsula are generally greater than those on the Kuril Islands,as is often the case with the size of their *** volcanic lakes under study can rapidly change their volume and shape under the influence of endogenous *** the first time for this region,on the base of repeated observations,underwater extrusive dome rate growth and the approximate rates of 2 lake level changes were *** observations of lakes in the Ksudach calderas(Kamchatka)and on Simushir Island indicate approximate rates of level changes:a decrease ranging within 0.5-0.6 m per year(over a 27-year observation interval)and an increase reaching up to 0.26 m per year(over a 48-year interval).The growth rate of the underwater extrusive dome in Lake Shtyubel has averaged 1-1.6 m per year over the past 25 *** analysis has facilitated the first generalization regarding the morphology and developmental features of crater and caldera lakes in the Kuril-Kamchatka region of Russia,representing an important step in their *** results obtained will provide a solid foundation for subsequent research in this region and may be of interest to researchers studying

关键词： volcanic lakes Echolocation survey volcanism Gashydrotherms Kamchatka Kuril Islands