检索结果-南通市图书馆

Applied Mathematics and Mechanics(English Edition) 2017年第2期38卷 191-216页

作者： d.v.dUNG d.T.dONG Faculty of Mathematics Mechanics and Informatics Vietnam National University Hanoi 100000 Vietnam Faculty of Civil Engineering University of Transport Technology Hanoi 100000 Vietnam

In this paper, the nonlinear analysis of stability of functionally graded ma- terial （FGM） sandwich doubly curved shallow shells is studied under thermo-mechanical loads with material properties obeying the general sigmoid law and power law of four ma- terial models. Shells are reinforced by the FGM stiffeners and rest on elastic foundations. Theoretical formulations are derived by the third-order shear deformation theory （TSdT） with the von Karman-type nonlinearity taking into account the initial geometrical im- perfection and smeared stiffener technique. The explicit expressions for determining the critical buckling load and the post-buckling mechanical and thermal load-deflection curves are obtained by the Galerkin method. Two iterative algorithms are presented. The effects of the stiffeners, the thermal element, the distribution law of material, the initial imper- fection, the foundation, and the geometrical parameters on buckling and post-buckling of shells are investigated.

关键词： functionally graded material (FGM) sandwich double curved shallow shell,thermo-mechanical stability FGM stiffener elastic foundation

biodiversity and interactions of acidophiles:Key to understanding and optimizing microbial processing of ores and concentrates

在线全文

学校读者我要写书评

暂无评论

中国有色金属学会会刊：英文版 2008年第6期18卷 1367-1373页

作者： d.b.JOHNSON School of biological Sciences Bangor University

采矿公司为从低档矿石恢复贱、宝贵的金属，并且为重新调停变得逐渐地知道 microbiological 途径的潜力从操作和放弃的矿地点排干的酸的、充满金属的废水。生物系统出现很多环境并且(有时) 超越常规途径的节俭的优点尽管他们的申请是，... 详细信息

采矿公司为从低档矿石恢复贱、宝贵的金属，并且为重新调停变得逐渐地知道 microbiological 途径的潜力从操作和放弃的矿地点排干的酸的、充满金属的废水。生物系统出现很多环境并且(有时) 超越常规途径的节俭的优点尽管他们的申请是，例如热冶学，别处于每种状况拨出。矿物质用微生物处理为提取黄金，铜，铀和钴被利用了，并且当前的开发正在指向另外的贱金属。最近，我们 biomining 环境，并且微生物怎么与对方一起交往的微生物学的差异的知识和理解有大增加。从模仿了搅动的坦克和堆生物反应器系统的实验室实验的结果证明了微生物引起的协会比氧化矿物质的 acidophiles 的纯文化更柔韧，并且也趋于在 bioleaching 和氧化简历的矿石更有效并且专注。纸论述了性质的简明评论和涉及硫化物矿物质的氧化的微生物引起的协会的相互作用，并且这些怎么可能被改编在 biomining 操作遇见未来挑战。

关键词：嗜酸细胞生物采矿生物多样性微生物加工

Magnetic ferrite/carbonized cotton fiber composites for improving electromagnetic absorption properties at gigahertz frequencies

在线全文

学校读者我要写书评

暂无评论

Journal of Materials Science & Technology 2021年第27期86卷 127-138页

作者： Sateesh bandaru Narashima murthy Ravindra Kulkarni Niall J.English School of Chemical and bioprocess Engineering University College DublinBelfieldDublin 4Ireland Scinva Chemicals and Pharmaceuticals Pvt Ltd Kumbalagodu Industrial AreaBangaloreIndia bvdU’s Poona College of Pharmacy ErandawanePuneIndia

Ferrite/carbon composited materials,especially the bio-derived composited materials possessing both environmental friendliness and outstanding microwave absorption performance,attract numerous attentions for solving the"electromagnetic problem"in the Gigahertz frequency *** this work,we demonstrate a bio-derived ferrite/carbon material by compositing functional carbonized cotton fibers(CCFs)and Fe_(3)O_(4)nanoparticles with optimized microwave-absorption *** adjusting the carbonization conditions systematically,the Fe_(3)O_(4)loading contents and the microwave absorption properties can be varied simultaneously-and,indeed,optimized and *** CCFs-Fe_(3)O_(4)composites exhibited a minimum reflection-loss capacity RL(d b)of-56.8 d b at 10.9 GHz with a thickness of 1.67 mm,and its effective absorption bandwidth(RL(d b)d b)was found to broaden to 7.1 *** characterizations,coupled with microstructure analyses,revealed that the enhancement in microwave absorption was triggered by the different microstructures of CCFs-Fe_(3)O_(4)composites-attributable to the different carbonization *** different conditions result in different amounts of Fe_(3)O_(4)attachment sites and lead to the enhancement of dielectric polarization at localized *** present work of bio-derived ferrite/carbon materials has important implications in understanding structure-performance relationships in dielectric-magnetic materials,and,meanwhile,could well be extended to a microwave-absorber design approach.

关键词： Electromagnetic absorption bio-derived material dielectric-magnetic composite Interfacial polarization

在线全文

学校读者我要写书评

暂无评论

大洋锰结核干式氯化研究

中国锰业 1989年第2期7卷 57-60,56页

作者： b.v.R.murthy 赵冰

本研究是采用于氯气从印度洋锰结核中提取铜、镍、钴、锰等有价金属。试验在电热硅管炉内进行,研究诸参数如温度、保持时间、加木炭的百分比、氯气流量、以及锰结核和木炭的百分比对不同参数的影响。通过适当的控制条件,成功地进行了优... 详细信息

本研究是采用于氯气从印度洋锰结核中提取铜、镍、钴、锰等有价金属。试验在电热硅管炉内进行,研究诸参数如温度、保持时间、加木炭的百分比、氯气流量、以及锰结核和木炭的百分比对不同参数的影响。通过适当的控制条件,成功地进行了优先提取铜、镍、钴、锰等有价金属的尝试。

关键词：锰结核干式氯化海

Grain Refinement in a Low Carbon Steel Through Multidirectional Forging

在线全文

学校读者我要写书评

暂无评论

Journal of Iron and Steel Research International 2012年第10期19卷 74-78页

作者： v Soleymani b Eghbali department of Materials Science Engineering Sahand University of TechnologyTabriz 51335Iran

Grain refinement is one of the successful and low-cost methods to develop metals having excellent combination of strength and ductility. Low carbon steel was deformed by using multidirectional forging (MdF) technique at room temperature. The influence of strain amount and annealing process on the microstructure and mechanical properties of investigated steel was studied. The grain refinement mechanism was studied by the microstructure observation. The results showed that the grain refinement was attained by multidirectional forging technique. The initial coarser grains of average 38 μm size fragmented into very fine ferrite with grain sizes of about 1.2 μm. After MdF, the strength properties improved significantly, although uniform elongation and elongation decreased with increasing strain.

关键词： multidirectional forging grain refinement annealing steel recrystallization

Ion heat transport in electron cyclotron resonance heated L-mode plasma on the T-10 tokamak

在线全文

学校读者我要写书评

暂无评论

Plasma Science and Technology 2024年第4期26卷 52-60页

作者： v.A.KRUPIN M.R.NURGALIEv A.R.NEMETS I.A.ZEMTSOv S.d.SUNTSOv T.b.MYALTON d.S.SERGEEv N.A.SOLOvEv d.v.SARYCHEv d.v.RYJAKOv S.N.TUGARINOv N.N.NAUMENKO National Research Centre“Kurchatov Institute” Moscow 123182Russia bauman Moscow State Technical University Moscow 105005Russia Institution“Project Center ITER” Moscow 123098Russia JSC“SOLAR” Minsk 220034Belarus

Anomalous ion heat transport is analyzed in the T-10 tokamak plasma heated with electron cyclotron resonance heating(ECRH) in second-harmonic extra-ordinary mode. Predictive modeling with empirical scaling for Ohmical heat conductivity shows that in ECRH plasmas the calculated ion temperature could be overestimated, so an increase of anomalous ion heat transport is required. To study this effect two scans are presented: over the EC resonance position and over the ECRH power. The EC resonance position varies from the high-field side to the low-field side by variation of the toroidal magnetic field. The scan over the heating power is presented with on-axis and mixed ECRH regimes. discharges with high anomalous ion heat transport are obtained in all considered regimes. In these discharges the power balance ion heat conductivity exceeds the neoclassical level by up to 10 times. The high ion heat transport regimes are distinguished by three parameters: the ratio Te/Ti, the normalized electron density gradient R/■, and the ion–ion collisionality νii~*. The combination of high Te/Ti, high νii~*, and R/■=6-10 results in values of normalized anomalous ion heat fluxes up to 10 times higher than in the low transport scenario.

关键词： tokamak L-mode electron cyclotron resonance heating ion heat transport

Grain boundary and microstructure engineering of Inconel 690 cladding on stainless-steel 316L using electron-beam powder bed fusion additive manufacturing

在线全文

学校读者我要写书评

暂无评论

Journal of Materials Science & Technology 2019年第2期35卷 351-367页

作者： I.A.Segura L.E.Murr C.A.Terrazas d.bermudez J.Mireles v.S.v.Injeti K.Li b.Yu R.d.K.Misra R.b.Wicker W.M.Keck Center for 3d Innovation The University of Texas at El Paso department of Mechanical Engineering The University of Texas at El Paso department of Metallurgical Materials and Biomedical Engineering The University of Texas at El Paso

This research explores the prospect of fabricating a face-centered cubic(fcc) Ni-base alloy cladding(Inconel 690) on an fcc Fe-base alloy(316 L stainless-steel) having improved mechanical properties and reduced sensitivity to corrosion through grain boundary and microstructure engineering concepts enabled by additive manufacturing(AM) utilizing electron-beam powder bed fusion(EPbF). The unique solidification and associated constitutional supercooling phenomena characteristic of EPbF promotes[100] textured and extended columnar grains having lower energy grain boundaries as opposed to random, high-angle grain boundaries, but no coherent {111} twin boundaries characteristic of conventional thermo-mechanically processed fcc metals and alloys, including Inconel 690 and 316 L *** addition to [100] textured grains, columnar grains were produced by EPbF fabrication of Inconel 690 claddings on 316 L stainless-steel substrates. Also, irregular 2–3 μm diameter, low energy subgrains were formed along with dislocation densities varying from 108 to 109 cm^2, and a homogeneous distribution of Cr_(23)C_6 precipitates. Precipitates were formed within the grains(with ~3 μm interparticle spacing),but not in the subgrain or columnar grain boundaries. These inclusive, hierarchical microstructures produced a tensile yield strength of 0.527 GPa, elongation of 21%, and vickers microindentation hardness of 2.33 GPa for the Inconel 690 cladding in contrast to a tensile yield strength of 0.327 GPa, elongation of 53%, and vickers microindentation hardness of 1.78 GPa, respectively for the wrought 316 L stainlesssteel substrate. Aging of both the Inconel 690 cladding and the 316 L stainless-steel substrate at 685?C for50 h precipitated Cr_(23)C_6 carbides in the Inconel 690 columnar grain boundaries, but not in the low-angle(and low energy) subgrain boundaries. In contrast, Cr_(23)C_6 carbides precipitated in the 316 L stainless-steel grain boundaries, but not in the low energy

关键词： Additive manufacturing Electron-beam powder bed fusion (EPbF) Inconel 690 cladding 316L stainless steel Grain boundary engineering Materials characterization Mechanical properties

derivation of Specific velocity of body Moving under Gravity with Zero Total Energy

在线全文

学校读者我要写书评

暂无评论

Journal of Applied Mathematics and Physics 2017年第1期5卷 1-6页

作者： T. v. b. S. Satyanarayana murthy Civil design department of Power Projects division BGR Energy Systems Limited Chennai India

Mathematical solutions predict abstract conditions that indicate limits or bounds for physical processes. Generally, experimental verifications and physical observations on physical processes validate the mathematical predictions. Sometimes these predictions lead to new theories and concepts that form basis of better understanding of the natural processes. Gravitational interactions between bodies are natural physical processes. A smaller body moves under the influence of gravity, due to the gravitational effect of another large body. Newton’s classical gravitational theory addresses the interactions at low velocities. Einstein’s general relativity provides firm basis for gravitational interactions. Observations over past 100 years prove the mathematical precision and predictions of general relativity. Einstein’s special relativity forms the foundation of quantum physics. In this paper, the author applies concepts of special relativity to classical two body Newtonian gravitational problem. The study predicts a new mathematically viable condition that when a body moves at a specific velocity derived in this paper, the total energy of the moving body is zero. The specific velocity is a constant. At velocities far less than specific velocity, the total energy is negative and is equal to classical value of half the potential energy. At velocities, greater the specific velocity the total energy is positive. The specific velocity condition also enables determination of specific mass of gravitating body, as well as the specific distance of the moving body from gravitating body, at which the total energy of moving body is zero.

关键词： Classical Gravitation Special Relativity Total Energy Gravitational Energy Specific velocity

Grain to outcrop-scale frozen moments of dynamic magma mixing in the syenite magma chamber,Yelagiri Alkaline Complex,South India

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Geoscience Frontiers 2014年第6期5卷 801-820页

作者： M.L.Renjith S.N.Charan d.v.Subbarao E.v.S.S.K.babu v.b.Rajashekhar Marine and Coastal Survey division Geological Survey of IndiaCochin 682037India Geochemistry division CSIR-National Geophysical Research InstituteHyderabad 500007India New Zealand Petroleum and Minerals Wellington 6037New Zealand

Magma mixing process is unusual in the petrogenesis of felsic rocks associated with alkaline complex worldwide. Here we present a rare example of magma mixing in syenite from the Yelagiri Alkaline Complex, South India. Yelagiri syenite is a reversely zoned massif with shoshonitic (Na2O t K2O?5e 10 wt.%, Na2O/K2O ? 0.5e2, TiO2d metaluminous character. Systematic modal variation of plagioclase (An11e16 Ab82e88), K-feldspar (Or27e95 Ab5e61), diopside (En34e40Fs11e18Wo46e49), biotite, and Ca-amphibole (edenite) build up three syenite facies within it and imply the role of in-situ fractional crystallization (FC). Evidences such as (1) disequilibrium micro-textures in feldspars, (2) microgranular mafic enclaves (MME) and (3) synplutonic dykes signify mixing of shoshonitic mafic magma (MgO ? 4e 5 wt.%, SiO2 ? 54e59 wt.%, K2O/Na2O ? 0.4e0.9) with syenite. Molecular-scale mixing of mafic magma resulted disequilibrium growth of feldspars in syenite. Physical entity of mafic magma preserved as MME due to high thermal-rheological contrast with syenite magma show various hybridization through chemical exchange, mechanical dilution enhanced by chaotic advection and phenocryst migration. In synplutonic dykes, disaggregation and mixing of mafic magma was confined within the conduit of injec-tion. Major-oxides mass balance test quantified that approximately 0.6 portions of mafic magma had interacted with most evolved syenite magma and generated most hybridized MME and dyke samples. It is unique that all the rock types (syenite, MME and synplutonic dykes) share similar shoshonitic and met-aluminous character;mineral chemistry, REE content, coherent geochemical variation in Harker diagram suggest that mixing of magma between similar composition. Outcrop-scale features of crystal accumu-lation and flow fabrics also significant along with MME and synplutonic dykes in syenite suggesting that Yelagiri syenite magma chamber had evolved through multiple physical processes like

关键词： Magma mixing disequilibrium textures Petrology Synplutonic dykes Geodynamics

Prognosis in stage II colon cancer:Expanding the horizons of risk factors

在线全文

学校读者我要写书评

暂无评论

World Journal of Gastrointestinal Oncology 2025年第2期17卷 28-34页

作者： María belén Novoa díaz Claudia Gentili María Julia Martín Pedro Carriere department of biología Bioquímica y FarmaciaUniversidad Nacional del Sur(UNS)-INBIOSUR(CONICET-UNS)Bahía Blanca 8000Buenos AiresArgentina department of biología Bioquímica y FarmaciaUniversidad Nacional del Sur(UNS)-INIBIBB(CONICET-UNS)Bahía Blanca 8000Buenos AiresArgentina

we critically review the authors’perspective and analyze the relevance of the results obtained in the original article of clinical research by Liu et *** consider that additional factors associated with colon cancer progression have recently been described in extensive clinical research,and should be included in this analysis to achieve a more accurate *** factors include inflammation,gut microbiota composition,immune status and nutritional balance,as they influence the post-surgical survival profile of patients with stage II colorectal *** also address the clinical implementation and limitations of these *** of the patient´s entire context is essential for selection of the most appropriate therapy.

关键词： Risk factor Prognosis Colon cancer Inflammation markers Tumor location