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NONOSCILLATORY COMBINATION OF MAC CORMACK AND WARMING-BEAM SCHEMES FOR HYPERBOLIC CONSERVA-TION LAWS

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Journal of Hydrodynamics 2000年第2期12卷 101-106页

作者： yu, heng Liu, yuping Fudan Univ Shanghai China

Based on the analysis of nonoscillatory conditions of second-order schemes, a very simple combination of the two famous second-order finite difference schemes, the Mac Cormack scheme and the Warming-Beam scheme, was achieved for hyperbolic conservation laws. It can avoid spurious oscillations near discontinuities and preserve uniformly second order accuracy in space and time. Numerical results show lower cost and even better resolution than ENO schemes under same conditions.

关键词： Finite difference method Nonlinear systems Oscillations

Combining optical and X-ray observations of galaxy clusters to constrain cosmological parameters

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Research in Astronomy and Astrophysics 2011年第7期11卷 776-786页

作者： heng yu Zong-Hong Zhu Department of Astronomy Beijing Normal University Beijing 100875 China

Galaxy clusters present unique advantages for cosmological *** we collect a new sample of 10 lensing galaxy clusters with X-ray observations to constrain cosmological *** redshifts of the lensing clusters lie between 0.1 and 0.6,and the redshift range of their arcs is from 0.4 to *** clusters are selected carefully from strong gravitational lensing systems which have both X-ray satellite observations and optical giant luminous arcs with known *** arcs usually appear in the central region of clusters,where mass can be traced with luminosity quite *** on gravitational lensing theory and a cluster mass distribution model,we can derive a ratio using two angular diameter *** is the distance between lensing sources and the other is that between the deflector and the source. Since angular diameter distance relies heavily on cosmological geometry,we can use these ratios to constrain cosmological ***,X-ray gas fractions of galaxy clusters can also be a cosmological *** there are a dozen parameters to be fitted,we introduce a new analytic algorithm,Powell＇s UOBYQA（Unconstrained Optimization By Quadratic Approximation） ,to accelerate our *** result demonstrates that this algorithm is an effective fitting method for such a continuous multi-parameter *** find an interesting fact that these two approaches are separately sensitive toΩΛandΩ*** combining them,we can get reasonable fitting values of basic cosmological parameters：ΩM=0.26 ＋0.04 -0.04,andΩΛ=0.82 ＋0.14 -0.16.

关键词： X-rays:galaxies:clusters—gravitational lensing—cosmological parameters

Double detonation drivers for a shock tube/tunnel

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Science China(Physics,Mechanics & Astronomy) 2004年第4期47卷 502-512页

作者： CHEN Hong FENG heng yu Hongru High Temperature Gas Dynamics Laboratory Institute of Mechanics Chinese Academy of SciencesBeijing 100080 China High Temperature Gas Dynamics Laboratory Institute of Mechanics Chinese Academy of SciencesBeijing 100080 China High Temperature Gas Dynamics Laboratory Institute of Mechanics Chinese Academy of SciencesBeijing 100080 China

ARecent progress on detonation drivers is reviewed. Performances of the forward detonation driver and backward detonation driver have been observed. To eliminate occurrence of a Taylor wave following the detonation wave in the primary driver and to improve the performance of the detonation driver, an additional backward detonation driver was proposed to attach to the end of the forward detonation driver. When the ratio of the initial pressures between the additional and the primary drivers becomes larger than or equal to a critical value, the Taylor wave will disappear, and thus a homogeneous driving gas with high pressure and high temperature can be generated. Furthermore, an over-driving detonation wave will be also obtained, which can increase the driving capability.

关键词： gaseous detonation, shock tube, shock tunnel.

Orbital Ordering Induced by Direct Coulomb Repulsion

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Communications in Theoretical Physics 2011年第3期55卷 527-531页

作者： HUANG yuan-Yie ZHANG yu-heng High Magnetic Field Laboratory Chinese Academy of Sciences and University of Science and Technology of ChinaHefei 230026 China

We consider the covalence characters of the 3d electron with the eg orbital freedoms and put forward a new mechanism of the orbital ordering （00） based on the direct coulomb repulsion in this article. The results show that the orbital-orbital interaction （OO-I） between the adjacent ions in 180-degree configuration is dominated by the superexchange energy accompanied by a weak orbital-spin coupling, and the OO-I in 90-degree configuration is monitored by the oxygen on-site coulomb repulsion. The ferro-OO is the stable ground state for the one-dimensional chain in the case of the 90-degree configuration.

关键词： orbital ordering coulomb repulsion orbital-spin coupling

Preparation and Characterization of Novel Ti-doped M-site Deficient Olivine LiFePO_4

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Chinese Chemical Letters 2006年第8期17卷 1093-1096页

作者： yu heng SUN Xing Quan LIU Chengdu Institute of Organic Chemistry Chinese Academy of Sciences Chengdu 610041 Graduate School of the Chinese Academy of Sciences Beijing 100039 College of Materials and Chemistry ＆ Chemical Engineering Chengdu University of Technology Chengdu 610059

A novel Ti-doped M-site deficient olivine LiFePO4, i.e. Li0.95Fe0.95Ti0.05PO4, was synthesized by a solid-state reaction method. XRD and VTR were used to characterize the as-prepared samples. As a cathode material for... 详细信息

关键词： LiFePO4 Ti-doped M-site deficient rate capability cathode material.

New model of linkage evolution for the transtensional fault systems in the Nanpu Sag of Bohai Bay Basin:Insight from seismic interpretation and analogue modelling

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Petroleum Science 2024年第4期21卷 2287-2310页

作者： yu-heng Wang Fu-Sheng yu Bao-Yin Zhao Ling-Jian Meng College of Geosciences China University of Petroleum(Beijing)Beijing102249China State Key Laboratory of Petroleum Resources and Prospecting China University of Petroleum(Beijing)Beijing102249China Jidong Oilfield Company PetroChina Limited CompanyTangshan063004HebeiChina

The evolution of faults within the same stress field is frequently influenced by numerous factors,involving the reactivation of pre-existing structures,stress transmission through ductile detachment layers,and the growth,interaction,as well as linkage of new fault *** study analyses a complex multi-phase oblique extension fault system in the Nanpu Sag(NPS)of the Bohai Bay Basin(BBB),***-resolution three-dimensional(3D)seismic data and analogue modelling indicate that the oblique extensional reactivation of pre-existing structures governs the sequential arrangement of fault segments in the caprock,and they dip synthetically to the reactivated fault at *** the NW-SE extension in the Eocene,the predominant movement of the pre-existing fault is ***,during the N-S extension since the Oligocene,inclined at *** the pre-existing fault,forming splay fault segments and ultimately creating large en-echelon arcuate faults linked by relay *** fault throw-distance(T-D)and laser scanning,we reconstructed the fault evolution model of oblique extension reactivation in the presence of a ductile detachment *** study illustrates that the arcuate faults can be categorized into linear master fault segments controlled by pre-existing structures,bending splay faults in the termination zone,and normal fault segments responding to the regional stress *** interaction between faults occurs among normal faults and strike-slip faults,and the kinematic unification of the two fault systems is accomplished in the intersection *** the faults continue to evolve,the new fault segments tend to relinquish the control of pre-existing structures and concentrate more on the development of planar and continuous major *** ductile detachment layer significantly contributes to the uniform distribution of strain,resulting in narrow shear zones and discontinuous normal faults in its absence.

关键词： Analogue modelling Transtensional deformation Fault linkage Fault intersection zone Nanpu Sag of Bohai Bay basin

A review of microfluidic approaches for investigating cancer extravasation during metastasis

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Microsystems & Nanoengineering 2018年第1期4卷 400-412页

作者： yu-heng Vivian Ma Kevin Middleton Lidan You yu Sun Institute of Biomaterials and Biomedical Engineering University of Toronto164 College StreetRoom 407TorontoON M5S 3G9Canada Department of Mechanical and Industrial Engineering University of Toronto5 King’s College RoadRoom 105TorontoON M5S 3G8Canada

Metastases,or migration of cancers,are common and severe cancer *** the 5-year survival rates of primary tumors have greatly improved,those of metastasis remain below 30%,highlighting the importance of investigating specific mechanisms and therapeutic approaches for *** devices have emerged as a powerful platform for drug target identification and drug response screening and allow incorporation of complex interactions in the metastatic microenvironment as well as manipulation of individual *** this work,we review microfluidic devices that have been developed to study cancer cell migration and extravasation in response to mechanical(section‘Microfluidic investigation of mechanical factors in cancer cell migration’),biochemical(section‘Microfluidic investigation of biochemical signals in cancer cell invasion’),and cellular(section‘Microfluidic metastasis-on-a-chip models for investigation of cancer extravasation’)*** highlight the device characteristics,discuss the discoveries enabled by these devices,and offer perspectives on future directions for microfluidic investigations of cancer metastasis,with the ultimate aim of identifying the essential factors for a‘metastasis-on-a-chip’platform to pursue more efficacious treatment approaches for cancer metastasis.

关键词： biochemical signal cancer cell migration cancer cell extravasation metastasis-on-a-chip cellular signal microfluidic mechanical signal

A unified model for ductile-to-brittle transition in body-centered cubic metals

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Journal of Materials Science & Technology 2023年第10期141卷 193-198页

作者： yu-heng Zhang En Ma Jun Sun Wei-Zhong Han State Key Laboratory for Mechanical Behavior of Materials Xi’an Jiaotong UniversityXi’an 710049China

Ductile-to-brittle transition(DBT)is a well-known phenomenon in body-centered-cubic(BCC)metals,in-termetallics and semiconductor materials.A quantitative prediction of the DBT temperature,however,has so far remained ***,we propose a unified model based on the efficacy of dislocation multi-plication as the controlling factor for DBT,with the dislocation source efficiency governed by the relative mobility of screw versus edge *** model successfully predicts the DBT temperature of iron,molybdenum and tungsten,and also covers the influence of grain size,initial dislocation density,and the multiplicity of dislocation sources.A comparison with experiments indicates that the model captures the key DBT features,providing new insight into the toughness of BCC metals.

关键词： Metals Ductile Brittle Dislocation Mobility

Inflammation and apoptosis accelerate progression to irreversible atrophy in denervated intrinsic muscles of the hand compared with biceps: proteomic analysis of a rat model of obstetric brachial plexus palsy

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Neural Regeneration Research 2020年第7期15卷 1326-1332页

作者： Xiao-heng yu Ji-Xin Wu Liang Chen yu-Dong Gu Department of Hand Surgery Huashan Hospital and Institutes of Biomedical SciencesFudan UniversityShanghaiChina Shanghai Key Laboratory of Peripheral Nerve and Microsurgery ShanghaiChina

In treating patients with obstetric brachial plexus palsy,we noticed that denervated intrinsic muscles of the hand become irreversibly atrophic at a faster than denervated *** a rat model of obstetric brachial plexus palsy,denervated intrinsic musculature of the forepaw entered the irreversible atrophy far earlier than denervated *** this study,isobaric tags for relative and absolute quantitation were examined in the intrinsic musculature of forepaw and biceps on denervated and normal sides at 3 and 5 weeks to identify dysregulated *** of pathways mapped by those proteins was analyzed by Kyoto Encyclopedia of Genes and Genomes *** 3 weeks,119 dysregulated proteins in denervated intrinsic musculature of the forepaw were mapped to nine pathways for muscle regulation,while 67 dysregulated proteins were mapped to three such pathways at 5 *** 3 weeks,27 upregulated proteins were mapped to five pathways involving inflammation and apoptosis,while two upregulated proteins were mapped to one such pathway at 5 *** 3 and 5 weeks,53 proteins from pathways involving regrowth and differentiation were *** 3 weeks,64 dysregulated proteins in denervated biceps were mapped to five pathways involving muscle regulation,while,five dysregulated proteins were mapped to three such pathways at 5 *** protein mapped to inflammation and apoptotic pathways was upregulated from one pathway at 3 weeks,while three proteins were downregulated from two other pathways at 5 *** proteins mapped to regrowth and differentiation pathways were upregulated from three pathways at 3 weeks,while two proteins were downregulated in another pathway at 5 *** results implicated inflammation and apoptosis as critical factors aggravating atrophy of denervated intrinsic muscles of the hand during obstetric brachial plexus *** experimental procedures and protocols were approved by the Experimental Animal Ethics Committee of Fudan Univ

关键词： apoptosis biceps denervation inflammation intrinsic muscles of the hand irreversible muscle atrophy isobaric tags for relative and absolute quantitation nerve regeneration proteomic rat models reversible muscle atrophy