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THE INFLUENcE OF PREcURSOR VARIABLES ON THE PHASE FORMATION, MIcROSTRUcTURE AND TRANSPORT PROPERTY OF Bi-2223/Ag TAPES

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Acta Metallurgica Sinica(English Letters) 2003年第2期16卷 84-89页

作者： c.H.jiang j.M.Yoo j.w.Ko G.w.Qiao Institute of Metal Research The Chinese Academy of SciencesShenyang 110016ChinaMaterials Engineering Dept.Korea Institute of Machinery&Materials66 Sangnam-DongChangwon641-010KoreaMaterials Engineering Dept.Korea Institute of Machinery&Materials66 Sangnam-DongChangwon641-010KoreaInstitute of Metal ResearchThe Chinese Academy of SciencesShenyang 110016China

The Bi-2223/Ag tapes were prepared with spray-died powders, which are of different particle sizes and phase assemblages by varying the annealing time in pure oxygen. Longer time annealing degraded the reactivity of precursor powder, which in turn resulted in an incomplete conversion from precursors to Bi-2223, porosity core and misaligned grains in fully processed tapes. The best jc in short pressed samples varied from 29.7 to 47kA/cm2 for the tapes made from different powders.

关键词： Bi-2223/Ag tape precursor powder critical current density

Maneuvering Modeling and Simulation of AUV Dynamic Systems with Euler-Rodriguez Quaternion Method

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china Ocean Engineering 2013年第3期27卷 403-416页

作者： c.w.chen j.S.Kouh j.F.Tsai Department of Science Engineering and Ocean Engineering National Taiwan University

The purpose of this study is to develop maneuvering models and systems of a simulator to improve the motion performance of autonomous underwater vehicles （AUVs） at the preliminary design stages in advance. The AUVs simulation systems based on the standard submarine equations of motion in six-degree-of-freedom （6-DOF） integrated with the Euler-Rodriguez quaternion method for representing singularity-free AUV attitude and time-saving calculation, and with a nonlinear control model for maneuvering and depth control simulations, time-marching in the fourth-order Runge-Kutta scheme. For validation of the simulation codes, results of the ISiMI AUV open-loop tests including turning test and zigzag test as well as an AUV simulator on the basis of Euler-angle method were used to compare with the quaternion-based AUV simulator. The computational results from the proposed simulator agree well with those from both the ISiMI AUV experiments and the Euler-angle based simulations. Additionally, a new maneuvering procedure, namely ＂put-out＂ was implemented to test directional stability for a large-scale AUV in the proposed AUV simulator that can be considered for vehicles in space as well as in constrained planes.

关键词： autonomous underwater vehicle (.4 UV) Euler-Rodriguez quaternion hydrodynamics maneuvering systemdynamics

Optical spectroscopy study of charge density wave order in Sr3Rh4Sn13 and(Sr0.5ca0.5)3Rh4Sn13

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Science china(Physics,Mechanics & Astronomy) 2017年第4期60卷 51-56页

作者： w.j.Ban H.E wang c.w.Tseng c.N.Kuo c.S.Lue N.L.wang Institute of Physics Chinese Academy of SciencesBeijing 100190China Department of Physics Cheng Kung UniversityTainan 70101China International center for Quantum Materials School of PhysicsPeking UniversityBeijing 100871China collaborative Innovation center of Quantum Matter Beijing 100871China

we perform optical spectroscopy measurement on single-crystal samples of Sr3Rh4Sn13 and （Sr0.5ca0.5）3Rh4Sn13. Formation of cDw energy gap was clearly observed for both single-crystal samples when they undergo the phase transitions. The existence of residual Drude components in σ1（ω） below Tcow indicates that the Fermi surface is only partially gapped in the cDw state. The obtained value of 2A/kBTcow is roughly 13 for both Sr3Rh4Sn13 and （Sr0.5ca0.5）3Rh4Sn13 compounds, which is considerably larger than the mean-field value based on the weak-coupling BcS theory. The measurements provide optical evidence for the strong coupling characteristics of the cDw phase transition.

关键词： charge density wave optical spectroscopy intermetallic compounds

A ONE-STOP LOGISTIc SERVIcES FRAMEwORK SUPPORTING GLOBAL SUPPLY cHAIN cOLLABORATION

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journal of Systems Science and Systems Engineering 2016年第2期25卷 229-253页

作者： Amy j.c. Trappey charles V. Trappey Sandy w.c. chang w.T. Lee Tun Nien Hsu Department of Industrial Engineering and Engineering Management National Tsing Hua University Hsinchu Taiwan China Department of Management Science National Chiao Tung University Taiwan China Technology center for Service Industries Industrial Technology Research Institute Taiwan China

A global enterprise must continuously improve the efficiency of logistic operations between supply chain collaborators. Integrating logistic services, resources, and necessary information flows in the supply chain to ensure efficiency and efficacy is critically important to these companies. Global logistic service companies face challenges from their clients to provide logistic services that are cost effective, accurate, and seamlessly integrate material, information and cash flows. In this research, an improved framework for one-stop logistic services is systematically designed, analyzed, and evaluated. The one-stop logistic service framework, defmed in four models, is developed to provide enterprises with integrated and comprehensive services within the global supply chain context. The levels of service importance are assessed using a four categories questionnaire. This research provides a case study of the implementation of one-stop logistic services in the distribution industry and demonstrates the framework operating under different demand conditions. Finally, system dynamics causal evaluation is used to evaluate the advantages of the logistic service framework.

关键词： One-stop logistic services logistic management supply chain management system dynamics modeling

Numerical study on hydrodynamic characteristics of spherical bubble contaminated by surfactants under higher Reynolds numbers

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chinese journal of chemical Engineering 2022年第5期35卷 268-283页

作者： Tao Sun Mingjun pang Yang Fei School of Mechanical Engineering and Rail Transit Changzhou UniversityChangzhou 213164China

It is of significance to investigate deeply the hydrodynamic featu res of the bubble co ntaminated by impurities in view of the fact that the industrial liquid is difficult to keep absolutely *** the basis of the finite volume method,the bubble interface contaminated by the surfactant(1-pentanol)is achieved through solving the concentration transport equations in liquid and along the bubble interface,and solving the absorption and desorption equation at the bubble *** the three-dimensional momentum equation is solved at the same *** is investigated in detail on the influence of interfacial contamination degrees(described with the cap angleθ)on hydrodynamic characteristics of the spherical bubble when the bubble Reynolds number(Re)is larger than ***θis realized by changing the surfactant concentration(c_(0)) in *** present results show that the hydrodynamic characteristics,such as interfacial concentration,interfacial shear stress,interfacial velocity and wake flow,are related to both Re and c_(0) for the contaminated *** c_(0) is relatively low in liquid(i.e.,the contamination degree of the bubble interface is relatively slight),the hydrodynamic characteristics of the bubble can still keep the 2 D features even if Re>*** decrease ofθor the increase of Re can promote the appearance of the unsteady wake *** the present investigation,when Re>200 andθ≤60°,the hydrodynamic characteristics of the bubble show the 3D phenomena,which indicates that axisymmetric model is no longer valid.

关键词： Bubble Higher Reynolds number Interfacial parameters wake flow Adsorption Desorption

Strategies towards robust interpretations of in situ zircon Lu-Hf isotope analyses

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Geoscience Frontiers 2020年第3期11卷 843-853页

作者： c.j.Spencer c.L.Kirkland N.M.w.Roberts N.j.Evans j.Liebmann School of Earth and Planetary Sciences The Institute for Geoscience Research(TIGeR)Curtin UniversityPerthAustralia Department of Geological Sciences and Geological Engineering Queen’s UniversityKingstonCanada centre for Exploration Targeting-curtin Node The Institute for Geoscience ResearchSchool of Earth and Planetary SciencesCurtin UniversityPerthAustrali Geochronology and Tracers Facility British Geological SurveyNottinghamUK john de Laeter centre GeoHistory Facility School of Earth and Planetary SciencesCurtin UniversityPerthAustralia

The combination of U-Pb and Lu-Hf compositions measured in zircon crystals is a remarkably powerful isotopic couplet that provides measures on both the timing of mineral growth and the radiogenic enrichment of the source from which the zircon *** U-Pb age documents the timing of zircon crystallization/recrystallization and Hf isotopes inform on the degree to which the host melt was derived from a radiogenic reservoir(*** mantle) versus an unradiogenic reservoir(*** continental crust),or some mixture of these *** ease of generating large quantities of zircon U-Pb and Lu-Hf data has been in large part facilitated by instrument ***,the dramatic increase in time constrained zircon Lu-Hf analyses in the Earth science community has brought to the fore the importance of careful data collection and reduction workflows,onto which robust geological interpretations may be *** this work,we discuss the fundamentals of Lu-Hf isotopes in zircon,which then allows us to provide a robust,accessible,methodology for the assessment of data ***,we discuss some novel techniques for:data visualization—that facilitates better transparency of data interpretation;integration of geographic information—that may reveal spatial trends where temporal trends were only apparent before;and some novel statistical evaluation tools—that may provide more rigorous interand intra-sample comparisons.

关键词： Zircon Geochronology Isotope geochemistry Lu-Hf isotopes Geostatistics Data visualization

Evolution of deformation twins with strain rate in a mediummanganese wear-resistant steel Fe-8Mn-1c-1.2cr-0.2V

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journal of Iron and Steel Research International 2019年第9期26卷 983-990页

作者： j. chen j.j.wang H.Zhang w.G.Zhang c.M.Liu Key Laboratory for Anisotropy and Texture of Materials Ministry of EducationNortheastern UniversityShenyang 110819LiaoningChina School of Materials Science and Engineering Northeastern UniversityShenyang 110819LiaoningChina Baosteel Special Steel co. Ltd.Shanghai 200940China Northeastern Institute of Metal Materials co. Ltd.Shenyang 110108LiaoningChina

Microstructure evolutions of the medium-manganese wear-resistant steel Fe-8Mn-1c-1.2cr-0.2V (in wt.%) with stacking-fault energy of 22 mj m-2 during deformation at strain rate ranging of 10^-2-1 s^-1 were analyzed by means of X-ray diffraction, field emission scanning electron microscopy and high-resolution transmission electron microscopy. The results indicate that the twinning-induced plasticity effect is the main strengthening mechanism of the studied steel, whilst the transformation-induced plasticity effect only occurs at high strain rate. with an increase in strain rate, volume fraction of the deformation twins, in particular that of the secondary twins, increases significantly along with decreasing average size. when applied strain rate is higher than 10^-1 s^-1, the parallel deformation twins are turned into a crossing morphology, and the original straight twin boundaries exhibit a ladder feature, which is attributed to the interactions between regular dislocations and twin dislocations at the twin boundary. The critical strain, a key indicator of the initiation of deformation twin, decreases with increasing strain rate. In addition, the ductility and strength of medium-manganese wear-resistant steel Fe-8Mn-1c-1.2cr-0.2V are mainly determined by the shape and volume fraction of deformation twins.

关键词： Medium-manganese wear-resistant steel Stacking fault Twinning-induced plasticity effect Secondary twin Strain hardening rate

Semi-empirical model of solar plages

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Science china Mathematics 2001年第4期44卷 528-535页

作者：方成丁明德 j.-c.Hénoux w.c.Livingston 1. Department of Astronomy Nanjing University 210093 Nanjing China 2. Observatoire de Paris DASOP-UMR8645 (CNRS) 92195 Meudon Cedex France 3. National Solar Observatory AZ85726-6732 Tucson USA

By use of the 2-m McMath-Pierce telescope at Kitt Peak, the high-quality spectra of a moderate-brightness plage near the center of solar disk were obtained. The data include seven spectral lines: Hα, Hβ, call H and K lines and infrared triplet. Under the assumption of plane-parallel atmosphere, the hydrostatic, transfer and statistic equilibrium equations were solved iteratively and the semi-empirical model of the plage has been obtained. It can well reproduce the observed seven line profiles. The model has been compared with two existing plage models. Further improvement has also been discussed.

关键词： plage solar activity atmospheric model

conformable fractional heat equation with fractional translation symmetry in both time and space

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chinese Physics B 2023年第4期32卷 125-129页

作者： w S chung A Gungor j Krız B c Lutfuoglu H Hassanabadi Department of Physics and Research Institute of Natural Science College of Natural ScienceGyeongsang National UniversityJinju 660-701Korea Mechanical Engineering Akdeniz UniversityAntalyaTurkey Department of Physics University of Hradec KraloveRokitanskeho 6250003 Hradec KraloveCzech Republic Department of Physics Akdeniz UniversityAntalyaTurkey Faculty of Physics Shahrood University of TechnologyShahroodIran

we investigate the fractional heat equation with fractional translation in both time and position with different fractional *** examples,we consider a rod and anα-disk with an initial constant temperature and discuss... 详细信息

关键词： fractional derivative heat equation conformable symmetry