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A new subregion mesh method for the investigation of the elastic-plastic impact in flexible multibody systems

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Acta Mechanica Sinica 2017年第1期33卷 189-199页

作者： peng Chen Jin-yang Liu guang-Can Lu Department of Engineering Mechanics School of Naval Architecture Ocean and Civil Engineering Shanghai Jiaotong University Shanghai 200240 China

Impact processes between flexible bodies often lead to local stress concentration and wave propagation of high frequency. Therefore, the modeling of flexible multibody systems involving impact should consider the local plastic deformation and the strict requirements of the spatial discretization. Owing to the nonlinearity of the stiffness matrix, the reduction of the element number is extremely important. For the contact-impact problem, since different regions have different requirements regarding the element size, a new subregion mesh method is proposed to reduce the number of the unnecessary elements. A dynamic model for flexible multibody systems with elastic-plastic contact impact is established based on a floating frame of reference formulation and complete Lagrange incremental nonlinear finite-element method to investigate the effect of the elastic-plastic deformation as well as spatial discretization. Experiments on the impact between two bodies are carried out to validate the correctness of the elastic-plastic model. The proposed formulation is applied to a slider-crank system with elastic-plastic impact.

关键词： Multibody dynamics Elastic-plastic impact Subregion mesh method Experiment

Coalescence Suppression in Flowing Polymer Blends Using Silica Rods with Different Surface Chemistries

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Chinese Journal of Polymer Science 2021年第4期39卷 474-483,I0007页

作者： Si-Ying Xiang Li-Sa-ya Ye ya-Jiang Huang ya-Dong Lv Mi-Qiu Kong guang-Xian Li College of Polymer Science and Engineering State Key Laboratory of Polymer Materials Engineering of ChinaSichuan UniversityChengdu 610065China

Silica rods with homogeneous(hydrophilic or hydrophobic)and amphiphilic surface properties were synthesized and their efficiencies in suppressing the flow-induced droplet coalescence of immiscible polyisobutylene(PIB)/polydimethylsiloxane(PDMS)blends were evaluated via in situ visualization *** flow-induced coalescence behavior of blends was found to strongly depend on the surface nature and concentration of silica rods added as well as the blend *** a trace amount of rods promoted coalescence,all kinds of rods demonstrated a morphology refinement effect at high rod *** compatibilization effects were obtained at high rod concentrations,especially for hydrophilic and amphiphilic *** on confocal laser scanning microscopy results,these phenomena observed were interpreted reasonably in terms of the selective distribution and aggregation of silica rods,which were suggested to be decisive for the stabilization mechanism and efficiency of these rods.

关键词： Immiscible polymer blends Flow Morphology Silica rods Surface chemistry

Subluminal and Superluminal Phenomena in a Four-Level Atom

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Communications in Theoretical Physics 2008年第7期50卷 197-200页

作者： HAN Ding-An ZENG ya-guang CAO Hui Physics Department Foshan University Foshan 528000 China

In a four-level atomic system, we investigate the light pulse propagation properties interacting with only one laser field. It is shown that in the steady state, the group velocity of the light pulse can be changed from subluminal to superluminal by varying the field detuning. Meanwhile, the effects of the field intensity on the group velocity are also shown. At last, with special parameters, the analytical solution for the group index is also obtained.

关键词： superluminal subluminal

A multi-enterprise quality function deployment paradigm with unstructured decision-making in linguistic contexts

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Journal of Systems Engineering and Electronics 2023年第4期34卷 966-980页

作者： peng Jian’gang XIA guang SUN Baoqun WANG Shaojie Intelligent Manufacturing Institute Hefei University of TechnologyHefei 230009China Institute of Automotive Engineering Hefei University of TechnologyHefei 230009China

This paper presents an operational framework of unstructured decision-making approach involving quality function deployment(QFD)in an uncertain linguistic ***,QFD is extended to the multi-enterprise paradigm in a real-world manufacturing ***,hesitant fuzzy linguistic term sets(HFLTSs),which facilitate the management and handling of information equivocality,are designed to construct a house of quality(HoQ)in the product planning *** technique of computing with words is applied to bridge the gap between mechanisms of the human brain and machine processes with fuzzy linguistic term ***,a multi-enterprise QFD pattern is formulated as an unstructured decision-making problem for alternative infrastructure project selection in a manufacturing *** inter-relationships of cooperative partners are directly matched with a back propagation neural network(BPNN)to construct the multi-enterprise manufacturing *** resilience of the manufacturing organization is considered by formulating an outranking method on the basis of HFLTSs to decide on infrastructure project ***,a real-world example,namely,the prototype manufacturing of an automatic transmission for a vehicle,is provided to illustrate the effectiveness of the proposed decision-making approach.

关键词： decision-making quality function deployment(QFD) uncertainty fuzzy set

Magnetized strange quark matter in the equivparticle model with both confinement and perturbative interactions

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Nuclear Science and Techniques 2016年第4期27卷 158-166页

作者： Cheng peng guang-Xiong peng Cheng-Jun Xia Jian-Feng Xu Shi-peng Zhang School of Physics University of Chinese Academy of Sciences Theoretical Physics Center for Science Facilities Institute of High Energy Physics Synergetic Innovation Center for Quantum Effects and Application Hunan Normal University Key Laboratory of Frontiers in Theoretical Physics Institute of Theoretical Physics

We investigated the properties of strange quark matter in an external strong magnetic field with both confinement and leading-order perturbative interactions considered. It was found that the leading-order perturbative interaction can stiffen the equation of state of magnetized quark matter, while the magnetic field lowers the minimum energy per baryon. By solving the Tolman–Oppenheimer–Volkoff equations, we obtain the internal structure of strange stars. The maximum mass of strange stars can be as large as 2 times the solar mass.

关键词：奇异夸克物质微扰磁化 e模型状态方程能量最小奥本海默内部结构

Meigs syndrome with pleural effusion as initial manifestation:A case report

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World Journal of Clinical Cases 2021年第21期9卷 5972-5979页

作者： ya-ya Hou Li peng Mei Zhou Department of Obstetrics and Gynaecology Union HospitalTongji Medical CollegeHuazhong University of Science and TechnologyWuhan 430000Hubei ProvinceChina Department of Pathology Union HospitalTongji Medical CollegeHuazhong University of Science and TechnologyWuhan 430000Hubei ProvinceChina Department of Respiratory Medicine Union HospitalTongji Medical CollegeHuazhong University of Science and TechnologyWuhan 430022Hubei ProvinceChina

BACKGROUND Meigs syndrome is a rare neoplastic disease characterized by the triad of benign solid ovarian tumor,ascites,and pleural *** postmenopausal women with pleural effusions,ascites,elevated CA-125 level,and pelvic masses,the probability of disseminated disease is ***,the final diagnosis is based on its histopathologic features following surgical removal of a mass *** we describe a case of Meigs syndrome with pleural effusion as the initial *** SUMMARY A 52-year-old woman presented with a 2-mo history of dry cough and oppression in the chest and was admitted to our hospital due to recurrent pleural effusion and gradual worsening of dyspnea that had occurred over the previous *** months before admission,the patient underwent repeated chest drainage and empirical anti-tuberculosis ***,the pleural fluid accumulation persisted,and the patient began to experience dyspnea on exertion leading to admission.A computed tomography scan of the chest,abdominal ultrasound,and magnetic resonance imaging confirmed the presence of right-sided pleural effusion and ascites with a right ovarian *** tumor markers showed raised *** a suspicion of a malignant tumor,the patient underwent laparoscopic excision of the ovarian mass and the final pathology was consistent with an ovarian *** the seventh day postoperation,the patient had resolution of the right-sided pleural *** Despite the relatively high risk of malignancy when an ovarian mass associated with hydrothorax is found in a patient with elevated serum levels of CA-125,clinicians should be aware about rare benign syndromes,like Meigs,for which surgery remains the preferred treatment.

关键词： Meigs syndrome Pleural effusion CA-125 Ovarian thecoma Case report

Electrochemical properties of LiNi_(0.5)Mn_(1.3)Ti_(0.2)O_4/Li_4Ti_5O_(12)cells

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International Journal of Minerals,Metallurgy and Materials 2012年第5期19卷 457-460页

作者： Guo-qiang Liu Xi Wang ya-jie Gao Lei Wen guang-yin Liu Jian-jie Zheng peng Cen Ying Li School of Materials and Metallurgy Northeastern University Shenyang 110004 China Institute of Metal Research Chinese Academy of Sciences Shenyang 110016 China

Spinel compounds LiNi0.5Mn1.3Ti0.2O4（LNMTO） and Li4Ti5O12 （LTO） were synthesized by different methods. The particle sizes of LNMTO and LTO are 0.5-2 and 0.5-0.8 μm, respectively. The LNMTO/LTO cell exhibits better electrochemical properties at both a low current rate of 0.2C and a high current rate of 1C. When the specific capacity was determined based on the mass of the LNMTO cathode, the LNMTO/LTO cell delivered 137 mA.h.g-1 at 0.2C and 118.2 mA-h-g-l at 1C, and the corresponding capacity retentions after 30 cycles are 88.5% and 92.4%, respectively.

关键词： lithium batteries titanium compounds nickel compounds manganese compounds oxides electrochemical properties

Properties of quark matter in a new quasiparticle model with QCD running coupling

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Science China(Physics,Mechanics & Astronomy) 2016年第6期59卷 49-57页

作者： Zhen yan Lu guang Xiong peng Jian Feng Xu Shi peng Zhang School of Physical Sciences University of Chinese Academy of Sciences Theoretical Physics Center for Science Facilities Institute of High Energy Physics

The running of the QCD coupling in the effective mass causes thermodynamic inconsistency problem in the conventional quasiparticle model. We provide a novel treatment which removes the inconsistency by an effective bag constant. The chemical potential dependence of the renormalization subtraction point is constrained by the Cauchy condition in the chemical potential space. The stability and microscopic properties of strange quark matter are then studied within the completely self-consistent quasiparticle model, and the obtained equation of state of quark matter is applied to the investigation of strange stars. It is found that our improved model can describe well compact stars with mass about two times the solar mass, which indicates that such massive compact stars could be strange stars.

关键词： quark matter quasiparticle model thermodynamic inconsistency

Gasification reactivity and kinetic parameters of coal chars for non-isothermal steam gasification

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Journal of Iron and Steel Research International 2021年第1期28卷 1-9页

作者： ya-jie Wang Hai-bin Zuo Jun Zhao guang-wei Wang State Key Laboratory of Advanced Metallurgy University of Science and Technology BeijingBeijing 100083China School of Metallurgical and Ecological Engineering University of Science and Technology BeijingBeijing 100083China

The gasification reactivity and kinetic parameters of coal chars for non-isothermal steam gasification were *** kind of lignite and three kinds of bituminous coals were used as the samples,and their coal ranks follow the ascending order:XBKL>ZJ>*** systematically analyzing factors affecting gasification reactivity,it was ascertained that the gasification reactivity is mostly determined by the carbonaceous *** gasification reactivity is inversely proportional to the coal rank,and the higher the coal rank,the lower the gasification reactivity.A new kinetic model was proposed to calculate the kinetic parameters,in which the reaction order was considered as an unknown kinetic *** reaction order n follows the ascending order:XB

关键词： Non-isothermal gasification Coal char Gasification reactivity Kinetic parameter Reaction order