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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

Establishing empirical relationships to predict grain size and tensile strength of friction stir welded AA 6061-t6 aluminium alloy joints

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transactions of Nonferrous Metals Society of China 2010年第10期20卷 1863-1872页

作者： S.RAJAKUMAR C.MURALIDHA RAN v.BALASUBRAMANIAN Department of Manufacturing Engineering Annamalai University

AA 6061-t6 aluminium alloy(Al-Mg-Si alloy) has gathered wide acceptance in the fabrication of light weight structures requiring a high specific strength and good corrosion *** with the fusion welding processes that are routinely used for joining structural aluminium alloys,friction stir welding(FSW) process is an emerging solid state joining process in which the material welded does not melt and *** strength is influenced by the grain size and tensile strength of the weld nugget ***,an attempt was made to develop empirical relationships to predict grain size and tensile strength of friction stir welded AA 6061-t6 aluminium alloy *** empirical relationships are developed by response surface methodology(RSM) incorporating FSW tool and process parameters.A linear regression relationship was also established between grain size and tensile strength of the weld nugget of FSW joints.

关键词： AA 6061-t6 alloy friction stir welding analysis of variance regression analysis grain size tensile strength

Energy conditions of the f(t,B) gravity dark energy model with the validity of thermodynamics

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Communications in theoretical Physics 2020年第8期72卷 109-118页

作者： S H Shekh v R Chirde P K Sahoo Department of Mathematics S.P.M.Science and Gilani Arts and Commerce CollegeGhatanjiYavatmalMaharashtra-445301India Department of Mathematics G.S.G.MahavidyalayaUmarkhed-445206India Department of Mathematics Birla Institute of Technology and Science-PilaniHyderabad CampusHyderabad-500078India

In this article, the analysis of tsallis holographic dark energy(which turns into holographic dark energy for a particular choice of positive non-additivity parameter δ) in modified f(t, B) gravity with the validity of thermodynamics and energy conditions for a homogeneous and isotropic FLRW Universe has been studied. the enlightenment of the field equation towards f(t,B)=αt^m+βB^n, made possible by the fact that the model is purely accelerating,corresponds to q=-0.54(Mamon and Das 2017 Eur. Phys.J.C 77 49). the generalized second law of thermodynamics is valid not only for the same temperature inside the horizon, but also for the apparent horizon for a change in temperature. the essential inspiration driving this article is to exhibit the applicability that the holographic dark energy achieved from standard tsallis holographic dark energy and the components acquired from f(t, B) gravity are identical for the specific bounty of constants. the analysis of energy conditions confirms that the weak energy condition and the null energy condition are fulfilled throughout the expansion, while violation of the strong energy condition validates the accelerated expansion of the *** the expansion, the model becomes a quintessence dominated model. the dominant energy condition is not observed initially when the model is filled with genuine baryonic matter,whereas it appears when the model is in the quintessence dominated era.

关键词： tsallis holographic dark energy f(t B)gravity energy conditions thermodynamics

Electrodeposition of aluminium and aluminium-copper alloys from a room temperature ionic liquid electrolyte containing aluminium chloride and triethylamine hydrochloride

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International Journal of Minerals,Metallurgy and Materials 2013年第9期20卷 909-916页

作者： P.v. Suneesh t.G. Satheesh Babu t. Ramachandran Department of Sciences Amrita School of Engineering Amrita Vishwa Vidyapeetham Amritanagar P. O.Coimbatore - 641112India

the electrodeposition of A1 and A1-Cu binary alloys on to gold substrates from a room temperature ionic liquid electrolyte containing A1C13-EtaNHC1 was studied. the electrochemical behavior of the electrolyte and the mechanism of deposition were investigated through cyclic voltammetry （Cv）, and the properties of deposits obtained were assessed by scanning electron microscopy with energy dispersive X-ray spectroscopy （SEM-EDS） and X-ray diffraction （XRD）. A1 of 70μm in thickness and an A1-Cu alloy of 30μm in thickness with 8at% copper were deposited from the electrolyte. SEM images of the deposits indicate that the A1 deposit was smooth and uniform, whereas the Al-Cu deposit was nodular. the average crystalline size, as determined by XRD patterns, was found to be （30±5） and （29±5） nm, respectively, for A1 and A1-Cu alloys. Potentiodynamic polarization （tafel plots） and electrochemical impedance spectroscopic （EIS） measurements showed that Al-Cu alloys are more corrosion resistant than Al.

关键词： electrodeposition aluminium copper alloys ionic liquids triethylamine hydrochloride copper acetylacetonate

Free vibration analysis of laminated FG-CNt reinforced composite beams using finite element method

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Frontiers of Structural and Civil Engineering 2019年第2期13卷 324-336页

作者： t.vO-DUY v.HO-HUU t.NGUYEN-tHOI Division of Computational Mathematics and Engineering Institute for Computational ScienceTon Due Thang UniversityHo Chi Minh CityVietnam Faculty of Civil Engineering Ton Due Thang UniversityHo Chi Minh CityVietnam

In the present study, the free vibration of laminated functionally graded carbon nanotube reinforced composite beams is analyzed. the laminated beam is made of perfectly bonded carbon nanotubes reinforced composite (CNtRC) layers. In each layer, single-walled carbon nanotubes are assumed to be unifonnly distributed (UD) or functionally graded (FG) distributed along the thickness direction. Effective material properties of the two-phase composites, a mixture of carbon nanotubes (CNts) and an isotropic polymer, are calculated using the extended nile of mixture. the first-order shear deformation theory is used to formulate a governing equation for predicting free vibration of laminated functionally graded carbon nanotubes reinforced composite (FG?CNtRC) beams. the governing equation is solved by the finite element method with various boundary conditions. Several numerical tests are perfbnned to investigate the influence of the CNts volume fractions, CNts distributions, CNts orientation angles, boundary conditions, length-to-thickness ratios and the numbers of layers on the frequencies of the laminated FG-CNtRC beams. Moreover, a laminated composite beam combined by various distribution types of CNts is also studied.

关键词： free vibration analysis laminated FG-CNtRC beam finite element method first-order shear deformation theory composite material

HI in High Gas-phase Metallicity Dwarf Galaxy WISEA J230615.06+143927.9

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Research in Astronomy and Astrophysics 2024年第1期24卷 292-299页

作者： Yan Guo C.Sengupta t.C.Scott P.Lagos Y.Luo Purple Mountain Observatory Chinese Academy of SciencesNanjing 210023China School of Astronomy and Space Sciences University of Science and Technology of ChinaHefei 230026China Institute of Astrophysics and Space Sciences(IA Porto) Rua das Estrelas4150-762PortoPortugal

We present resolved Giant Metrewave Radio telescope H I observations of the high gas-phase metallicity dwarf galaxy WISEA J230615.06+143927.9(z = 0.005)(hereafter J2306) and investigate whether it could be a tidal Dwarf Galaxy(tDG) candidate. tDGs are observed to have higher metallicities than normal dwarfs. J2306 has an unusual combination of a blue g-r color of 0.23 mag, irregular optical morphology and high-metallicity(12 +log(O/H) = 8.68 ± 0.14), making it an interesting galaxy to study in more detail. We find J2306 to be an H I rich galaxy with a large extended, unperturbed rotating H I disk. Using our H I data we estimated its dynamical mass and found the galaxy to be dark matter(DM) dominated within its H I radius. the quantity of DM, inferred from its dynamical mass, appears to rule out J2306 as an evolved tDG. A wide area environment search reveals J2306 to be isolated from any larger galaxies which could have been the source of its high gas metallicity. Additionally, the H I morphology and kinematics of the galaxy show no indication of a recent merger to explain the *** detailed optical spectroscopic observations of J2306 might provide an answer to how a seemingly ordinary irregular dwarf galaxy achieved such a high level of metal enrichment.

关键词： galaxies:abundances galaxies:dwarf galaxies:irregular radio lines:galaxies radio lines:ISM

Development of Biocomposites of MCC Extracted From Non-Wood Sources

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Journal of Renewable Materials 2019年第11期7卷 1109-1119页

作者： t.Dipin t.v.Jinitha E.Purushothaman Department of Chemistry University of CalicutMalappuramKerala673635India

the present work mainly focuses on the estimation of various components and the extraction of microcrystalline cellulose(MCC)from non-wood sources like Country Almond/Badam shell through acid *** hydrolyzed MCC was successfully used as reinforcement for development of *** Almond/Badam trees are found all over Kerala,India and they give nuts once in a *** the nut shells are discarded and are becoming one of the sources of agricultural *** this investigation various components were isolated from the Country Almond shells and they were characterised using different spectral and analytical techniques thereby the composition of Country Almond shells was successfully determined for the first *** properties of MCC especially the crystalline nature depends on the source from which is ***-IR spectra give evidence for the chemical structure of *** of MCC was evidenced from scanning electron *** electron microscopy and atomic force microscopy reveal the agglomerated bundles of particles and rough surface of *** extracted MCC was found to contain Cellulose I and Cellulose II polymorphs,and this was confirmed from the X-ray diffraction(XRD)*** MCC extracted from Country Almond shells has reasonably good thermal *** casting method was adopted for the development of green composite of Poly(vinyl alcohol)reinforced with MCC extracted from Country Almond *** mechanical property of developed composites has been enhanced by the addition of *** dispersion of MCC in the PvA matrix and flocculation of MCC significantly influence the mechanical strength.

关键词： Country almond/Badam shell microcrystalline cellulose bio composites

Energy Proficient Reduced Coverage Set with Particle Swarm Optimization for Distributed Sensor Network

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Computer Systems Science & Engineering 2023年第5期45卷 1611-1623页

作者： t.v.Chithra A.Milton Department of Computer Science and Engineering Arunachala College of Engineering for WomenManavilaiTamil Nadu629203India Department of Electronics and Communication Engineering St.Xavier’s Catholic College of EngineeringChunkankadaiTamil Nadu629003India

Retransmission avoidance is an essential need for any type of wireless *** retransmissions induce the unnecessary presence of redundant data in every accessible *** storage capacity is symmetrical to the size of the memory,less storage capacity is experienced due to the restricted size of the respective *** this proposed work,we have discussed the integration of the Energy Proficient Reduced Coverage Set with Particle Swarm Optimization(PSO).PSO is a metaheuristic global search enhancement technique that promotes the searching of the best nodes in the search *** is integrated with a Reduced Coverage Set,to obtain an optimal path with only high-power transmitting *** Proficient Reduced Coverage Set with PSO constructs a set of only best nodes based on the fitness solution,to cover the whole *** proposed algorithm has experimented with a different number of *** has been made between original and improved algorithm shows that improved algorithm performs better than the existing by reducing the redundant packet transmissions by 18%~40%,thereby increasing the network lifetime.

关键词： Wireless sensor network reduced coverage set swarm intelligence particle swarm optimization energy consumption

Effects of varying Alx moles on structure and luminescence properties of ZnAl_(x)O_(1.5x+1):0.1 mol%tb^(3+)nanophosphors prepared using citrate sol-gel method

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Journal of Rare Earths 2023年第3期41卷 358-364,I0002页

作者： v.M.Maphiri L.t.Melato M.R.Mhlongo t.t.Hlatshwayo t.E.Motaung L.F.Koao S.v.Motloung Department of Physics Sefako Makgatho Health Science UniversityP.O.Box 94Medunsa0204South Africa Department of Mathematics Non Destructive Testing and PhysicsVaal University of TechnologyAndries Potgieter BlvdVanderbijlpark1900South Africa Department of Physics University of PretoriaPretoria0002South Africa Department of Chemistry School of Science in the College of Science Engineering and TechnologyUniversity of South AfricaPreller StreetMuckleneuk RidgeCity of TshwaneP.O Box 392UNISA 0003South Africa Department of Chemistry Sefako Makgatho Health Science UniversityP.O.Box 94Medunsa0204South Africa Department of Physics University of the Free State(Qwaqwa Campus)Private Bag X13Phuthaditjhaba 9866South Africa Department of Chemical and Physical Sciences Walter Sisulu UniversityMthathaSouth Africa

Un-doped and ZnAl_(x)O_(1.5x+1):0.1 mol%tb^(3+)(ZAOt)nano-powders were synthesized via citrate sol-gel *** AIx moles were varied in the range of 0.25≤x≤*** X-ray powder diffraction(XRD)data reveal that for xthe prepared samples crystal structure consists of mixed phases of the cubic ZnAl_(2)O_(4) and hexagonal ZnO phases,while for x>1.5 the structure consists of single phase of cubic ZnAl_(2)O_(4).the Raman and Fourier-trans form infrared(FtIR)vibrational spectroscopy show the presence of vibrations emanating ZnAl_(2)O_(4) *** electron microscopy(SEM)and transmission electron microscopy(tEM)show the presence of irregular sphere at x>2.0 attributed to ZnAl_(2)O_(4).the photoluminescence(PL)spectroscopy reveals emissions from both the host and tb^(3+)*** from tb^(3+)are observed at 382,414,439,458 nm and 489,545,585,621 nm,which were attributed to the^(5)D_(3)→^(7)F_(6,5,4,2) and ^(5^)D_(4)→^(7)F_(6,5,4,3),*** results confirm that the tb^(3+)occupation site depends on the Alx *** International Commission on Illumination(CIE)colour chromaticity shows that the emission colour can be tuned from blue to green by varying the AIx moles.

关键词： Citrate sol-gel ZnAl_(2)O_(4)/ZnO tb^(3+)-doped Al_(x)moles Photoluminescence Rare earths

Regenerative medicine of pancreatic islets

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World Journal of Gastroenterology 2020年第22期26卷 2948-2966页

作者： Irina v Arutyunyan timur Kh Fatkhudinov Andrey v Makarov Andrey v Elchaninov Gennady t Sukhikh National Medical Research Center for Obstetrics Gynecology and Perinatology named after Academician V.I.Kulakov of Ministry of Healthcare of Russian FederationMoscow 117997Russia Research Institute of Human Morphology Moscow 117418Russia Peoples Friendship University of Russia Moscow 117198Russia Pirogov Russian National Research Medical University Ministry of Healthcare of the Russian FederationMoscow 117997Russi

the pancreas became one of the first objects of regenerative medicine,since other possibilities of dealing with the pancreatic endocrine insufficiency were clearly *** number of people living with diabetes mellitus is currently approaching half a billion,hence the crucial relevance of new methods to stimulate regeneration of the insulin-secretingβ-cells of the islets of *** restrictions on the islet regeneration are very tight;nevertheless,the islets are capable of physiological regeneration viaβ-cell self-replication,direct differentiation of multipotent progenitor cells and spontaneousα-toβ-orδ-toβ-cell conversion(trans-differentiation).the existing preclinical models ofβ-cell dysfunction or ablation(induced surgically,chemically or genetically)have significantly expanded our understanding of reparative regeneration of the islets and possible ways of its *** ultimate goal,sufficient level of functional activity ofβ-cells or their substitutes can be achieved by two prospective broad strategies:β-cell replacement andβ-cell ***“regeneration”strategy aims to maintain a preserved population ofβ-cells through in situ exposure to biologically active substances that improveβ-cell survival,replication and insulin secretion,or to evoke the intrinsic adaptive mechanisms triggering the spontaneous non-β-toβ-cell ***“replacement”strategy implies transplantation ofβ-cells(as non-disintegrated pancreatic material or isolated donor islets)orβ-like cells obtained ex vivo from progenitors or mature somatic cells(for example,hepatocytes orα-cells)under the action of small-molecule inducers or by genetic *** believe that the huge volume of experimental and clinical studies will finally allow a safe and effective solution to a seemingly simple goal-restoration of the functionally activeβ-cells,the innermost hope of millions of people globally.

关键词： Pancreas Islets of langerhans β-cells Regeneration Replacement transplantation Reprogramming