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Applied Mathematics and Mechanics(English Edition) 2025年第1期46卷 81-100页

作者： S.SAURABH R.KIRAn D.SInGH R.vAISH v.S.CHAUHAn School of Mechanical and Materials Engineering Indian Institute of Technology Mandi

Bio-inspired helicoidal composite laminates, inspired by the intricate helical structures found in nature, present a promising frontier for enhancing the mechanical properties of structural designs. Hence, this study provides a comprehensive investigation into the nonlinear free vibration and nonlinear bending behavior of bio-inspired composite plates. The inverse hyperbolic shear deformation theory(IHSDT) of plates is employed to characterize the displacement field, with the incorporation of Green-Lagrange nonlinearity. The problem is modeled using the C0finite element method(FEM), and an in-house code is developed in the MATLAB environment to solve it numerically. various helicoidal layup configurations including helicoidal recursive(HR), helicoidal exponential(HE), helicoidal semi-circular(HS), linear helicoidal(LH), and Fibonacci helicoidal(FH)with different layup sequences and quasi-isotropic configurations are studied. The model is validated, and parametric studies are conducted. These studies investigate the effects of layup configurations, side-to-thickness ratio, modulus ratios, boundary conditions, and loading conditions at different load amplitudes on the nonlinear vibration and nonlinear bending behaviors of bio-inspired composite plates. The results show that the laminate sequence exerts a substantial impact on both nonlinear natural frequencies and nonlinear bending behaviors. Moreover, this influence varies across different side-to-thickness ratios and boundary conditions of the bio-inspired composite plate.

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Uranium Isotope variations(234U/238U and 238U/235U)and Behavior of U-pb Isotope System in the vershinnoe Sandstone-Type Uranium Deposit,vitim Uranium Ore District,Russia

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Journal of Earth Science 2022年第2期33卷 317-324页

作者： v.n.Golubev I.v.Chernyshev B.T.Kochkin n.n.Tarasov G.v.Ochirova A.v.Chugaev Institute of Geology of Ore Deposits PetrographyMineralogy and GeochemistryRussian Academy of SciencesMoscow 119017Russia

The U-pb isotope system and uranium isotope composition(235U/238U and 234U/238U)were studied in a number of samples from the vertical section of the uranium ore body at the vershinnoe sandstone-type deposit,vitim uranium ore district,*** parameters were determined to broadly *** of the 234U/238U ratio from the equilibrium value indicate that the uranium ore was not completely conserved during the postore stage,and uranium was determined to continue migrating at the *** of the U-pb isotope age value and 234U/238U isotope ratio provides an insight into the migrate direction of uranium in the ore *** broad variations(137.377–137.772)in the 238U/235U ratio over the vertical section of the ore body can be explained by the different settings of the samples relative to the ore deposition front and changes in the redox conditions when this front *** fact that theδ238U and K234/238 values are correlated indicates that the transfer of the 234U isotope into the aqueous phase may have been coupled with isotope fractionation in the 238U-235U system during the postformation uranium migration within the orebody.

关键词： sandstone-type uranium deposit U-pb age uranium isotope composition ore deposit geology

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physical vapor transport growth and morphology of Bi2Se3 microcrystals

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particuology 2016年第3期14卷 118-122页

作者： v.v. Atuchin S.v. Borisov T.A. Gavrilova K.A. Kokh n.v. Kuratieva n.v. pervukhina Laboratory of Optical Materials and Structures Institute of Semiconductor Physics SB RAS Novosibirsk 630090 Russia Functional Electronics Laboratory Tomsk State University Tomsk 634050 Russia Laboratory of Semiconductor and Dielectric Materials Novosibirsk State University Novosibirsk 630090 Russia Laboratory of Crystul Chemistry Institute of Inorganic Chemistry SB RAS Novosibirsk 630090 Russia Laboratory of nanodiagnostics and nanolithography Institute of Semiconductor Physics SB RAS Novosibirsk 630090 Russia Laboratory of Crystal Growth Institute of Geology and Mineralogy SB RAS Novosibirsk 630090 Russia Geology and Mineralogy Department Novosibirsk State University Novosibirsk 630090 Russia Spintronics Laboratory Saint Petersburg State University Saint Petersburg 198504 Russia Laboratory of Research Methods of Composition and Structure of Functional Materials Novosibirsk State University Novosibirsk 630090 Russia

High-quality Bi2Se3 microcrystals were grown by the physical vapor transport （pvT） method without using a foreign transport agent. The microplate crystals grown under the optimal temperature gradient are well faceted and have dimensions up to -200 μm, The growth proceeds by the layer-by-layer mecha- nism with the formation of flat low-growth rate facets. The phase composition of the grown crystals was identified by the X-ray single crystal structure analysis in space group R3m, a = 4.1356（3）, C= 28.634（5）A, Z=3 （R=0.0147）. The most probable twin planes in the tetradymite structure were evaluated by the pseudo translational sublattice merhad.

关键词： Bi2Se3 physical vapor transport Structure Twin

Disproportionation of ethylbenzene in the presence of C_8 aromatics

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Journal of natural Gas Chemistry 2009年第3期18卷 369-374页

作者： n.Sharnappa S.pai v.v.Bokade Catalysis Division National Chemical Laboratory

The selective synthesis of p-diethylbenzene （p-DEB） by disproportionation of ethylbenzene （EB） in the presence of aromatics like m- and p- xylene isomers has been studied over a pore size regulated HZSM-5 catalyst. The industrial feed having different compositions of ethylbenzene and xylene isomers was used for the experimentation. Hence, they were expected to hinder the movement of reactant molecules both on the external surface and within the zeolite channels. It was observed that irrespective of the different feed compositions the concentration of the xylene isomers was intact in the product. There is no other byproducts formation like para-ethylmethyl benzene. The effects of varying the concentration of aromatic compounds in the feed on ethylbenzene conversion and product distribution over the parent and modified H-ZSM-5 catalyst have been discussed. Ethylbenzene disproportionation reaction follows the pseudo first order reaction with an activation energy of 8.6 kcal/mol.

关键词： ethylbenzene xylene isomers catalyst disproportionation diethylbenzene

Express Methods for Measurement of Electroconductivity of Semiconductor Layered Crystal

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Chinese physics Letters 2015年第11期32卷 114-117页

作者： FILIppOv v. v. vLASOv A. n. Department of physics Lipetsk State Pedagogical University Lipetsk 398020 Russian Federation Department of natural Sciences and Technical Disciplines the Branch in Lipetsk of Moscow State University of Technologies and Management Lipetsk 398006 Russian Federation

We describe theoretically the grounded method of measuring the conductivity of anisotropic layered semiconductor materials. The suggested method implies the use of a four-probe testing device with a linear arrangement of probes. The final expressions for identifying the electrical conductivity are presented in the form of a series of analytic functions. The suggested method is experimentally verified, and practical recommendations of how to apply it are also provided.

关键词： Express Methods for Measurement of Electroconductivity of Semiconductor Layered Crystal

Monitoring of ground subsidence movements over territory of mines being flooded in Budyonnovsky and proletarsky districts in Donetsk city with help of GpS-technology

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中国有色金属学会会刊：英文版 2005年第S1期15卷 266-268页

作者： A.v. Antsiferov Y.n. Gavrilenko n.n. Kiselyov UkrnIMI nAS Ukraine Donetsk 83121 UkraineDonetsk National Technical University Donetsk 83000 UkraineUkrNIMI NAS Ukraine Donetsk 83121 Ukraine

This paper considers the processes of activation in ground subsidence movements in flooding mine workings of mines being liquidated in two districts in Donetsk city on the area of more than 60km^2. A concept is given to build up control network of geomechanical monitoring in conditions of existing old mining operations at shallow depths (down to 100m), strong damages of objects of urban building. Given are GpS network structure, layouts for location of basic and local profile lines, special control stations for monitoring ground subsidence movements over the territory of mines being flooded. Results of the series of observations made are discussed and their accuracy is analyzed.

关键词： ground surface movement activation GpS network geomechanical monitoring mine

Torsion Completeness of Sylow p-Groups in Semisimple Group Rings

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Acta Mathematica Sinica,English Series 2004年第5期20卷 893-898页

作者： p.v.DAnCHEv Mathematical Department Plovdiv State UniversityPlovdiv 4000Bulgaria Insurance Supervision DirectorateMinistry of FinanceSofia 1000Bulgaria

Let G be an abelian p-group and K be a field of the first kind with respect to p of charK p and of s_p(K)=n or n∪p.Then it is shown that the normed Sylow p-subgroup S(KG)is torsion complete if and only if G is boun... 详细信息

Let G be an abelian p-group and K be a field of the first kind with respect to p of charK p and of s_p(K)=n or n∪v.Then it is shown that the normed Sylow p-subgroup S(KG)is torsion complete if and only if G is bounded(Theorem 1).An analogous fact is proved for the case when K is of the second kind(Theorem 2).These completely settle a conjecture posed by us in ***. ***.(1993)and are also a supplement to our result in the modular case published in Acta ***.(1997).

关键词： normalized p-units Fields of the first and of the second type Torsion complete primary components

Measurements of the γγ＊ → π^0 and γγ＊ → ηc transition form factors at BABAR

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Chinese physics C 2010年第6期34卷 816-821页

作者： v.p.Druzhinin Budker Institute of nuclear physics

We present measurements of the γγ＊ → π^0 transition form factor for the momentum transfer range Q^2=4-40 Gev^2 and the γγ＊ → ηc transition form factor for the range Q^2=2-50 Gev^2. The current status of measurements of the meson-photon transition form factors for the η and η＇ mesons is discussed. The results of the measurement of the ηc mass, total and two-photon widths are also presented.

关键词： two-photon interaction pseudoscalar meson transition form factor pi0 eta eta(958) etac

Anomalous acceleration of ions in a plasma accelerator with an anodic layer

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plasma Science and Technology 2018年第3期20卷 95-105页

作者： v M BARDAKOv S D IvAnOv A v KAZAnTSEv n A STROKIn A n STUpIn Binhao JIAnG Zhenyu WAnG Irkutsk State Transport University Chernyshevsky Str.15664074IrkutskRussia national Research Irkutsk Technical University Lermontova Str.83664074IrkutskRussia Department of Electrical Engineering Harbin Institute of TechnologyHarbin 150001People's Republic of China

In a plasma accelerator with an anodic layer(pAAL),we discovered experimentally the effect of‘super-acceleration'of the bulk of the ions to energies W exceeding the energy equivalent to the discharge voltage v_(d).The E×B discharge was ignited in an environment of atomic argon and helium and molecular *** charged argon ions were accelerated most effectively in the case of the largest discharge currents and pressure p of the working *** ions with W〉ev_(d)(e being the electron charge)were only recorded at maximum *** nitrogen was not accelerated to energies W〉e v_(d).Anomalous acceleration is realized in the range of radial magnetic fields on the anode 2.8×10^(–2)≤B_(rA)≤4×10^(–2)*** was also found analytically that the cathode of the accelerator can receive anomalously accelerated *** this case,the value of the potential in the anodic layer becomes higher than the anode potential,and the anode current exceeds some critical *** modeling in terms of the developed theory showed qualitative agreement between modeling data and measurements.

关键词： plasma sources particle orbit and trajectory particle measurements

Magnetic Behaviour of Tb/Si nanoscale Multilayers with Small Thickness of Rare Earth Layers

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Chinese physics Letters 2007年第6期24卷 1717-1719页

作者： A.v. Svalov v.O. vas'kovskiy G.v. Kurlyandskaya J.M. Barandiaran n.n. Schegoleva A.n. Sorokin Ural State University Lenin Avenue 51 620083 Ekaterinburg Russia Universidad del pals vasco Upv-EHU Facultad de Ciencias Depto Electricidad yVElectr6nica Apdo. 644'48080 Bilbao Spain Institute of Metal physics Ural Branch of RAS Kovalevskaya str. 18 620219 Ekaterinburg Russia

We report the magnetic properties of Tb/Si multilayers obtained by rf-sputtering at the Tb layer thickness LTb = 3 nm. Analysis of the magnetization processes indicates more complex behaviour than canonical spinglass transition. It is more probable that these multilayers contain both Tb superparamagnetic particles and Tb-Si spin-glass alloys.

关键词： SpIn-GLASS TRAnSITIOn GD/W MULTILAYERS TERBIUM FILMS nAnOpARTICLES