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Power output and efficiency optimization of endoreversible non-isothermal chemical engine via Lewis analogy

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Science China(Technological Sciences) 2023年第9期66卷 2651-2659页

作者： CHEN LinGen xia ShaoJun Institute of Thermal Science and Power Engineering Wuhan Institute of TechnologyWuhan 430205China School of Mechanical&Electrical Engineering Wuhan Institute of TechnologyWuhan 430205China School of Power Engineering Naval University of EngineeringWuhan 430033China

Compared with endoreversible heat engine with pure heat transfer and endoreversible isothermal chemical engine with pure mass transfer,endoreversible non-isothermal chemical engine(ENICE)is a more reasonable model of practical mass exchanger,solid device and chemo-electric *** exists heat and mass transfer(HMT)simultaneously between working fluid and chemical potential reservoir in *** is coupled HMT effect that in ENICE should be *** are two ways to consider this coupled *** is based on Onsager equations,and another is based on Lewis *** the mathematical and physical description of the above HMT process,the model using Onsager equations are more appropriate in the linear HMT region not far from the equilibrium state,while that based on Lewis analogy is more appropriate in nonlinear HMT region far from the equilibrium *** from the previous research on the power optimization of ENICEs with Onsager equations,this paper optimizes power and efficiency of ENICE based on Lewis *** processes are assumed to obey Newtonian heat transfer law(q∝ΔT,and T is temperature)and Fick's diffusive mass transfer law(g∝Δc,and c is concentration),*** results of power output and corresponding vector efficiency(η_(T)andη_(μ))of ENICE are obtained,which provide important parallel results with those based on Onsager *** include special cases for endoreversible Carnot heat engine with q∝ΔT and endoreversible isothermal chemical engine with g∝Δ*** Lewis analogy in the modelling of ENICEs with simultaneous HMT is an important *** provides important analytical and numerical results different from those with Onsager equations obtained previously and enriches the research contents of *** research results in this paper have a certain guiding significance for the optimal designs of single irreversible NICEs,multistage NICE systems,practical mass exchangers,solid devices,chemo-electric syste

关键词： finite time thermodynamics endoreversible non-isothermal chemical engine Lewis analogy heat and mass transfer vector efficiency maximum power output

Research on microcapsules of phase change materials

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Rare Metals 2006年第Z1期25卷 393-399页

作者： DAI xia SHEN xiaodong Material College of Nanjing University of Technology Nanjing 210009 China Material College of Nanjing University of Technology Nanjing 210009 China

Microcapsule technology is a kind of technology wrapping the solid or liquid into minute-sized particles within the field of micrometer or millimeter with film forming materials. This thesis introduces microcapsule technology of phase change materials and its main functions and the structural composition, preparation methods and characterization technology of microcapsule of phase change materials. The microcapsule of phase change materials is small in size and its temperature remains unchanged during the process of heat absorption and heat release. It is of great value in research and application prospect due to these characteristics.

关键词： phase change material microcapsule phase change material surface polymerization preparation

A hexahedron element formulation with a new multi-resolution analysis

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Science China(Physics,Mechanics & Astronomy) 2015年第1期58卷 65-74页

作者： xia YiMing CHEN ShaoLin Civil Engineering Department Nanjing University of Aeronautics and Astronautics

A multiresolution hexahedron element is presented with a new multiresolution analysis(MRA)*** MRA framework is formulated out of a mutually nesting displacement subspace sequence,whose basis functions are constructed of scaling and shifting on element domain of a basic node shape *** basic node shape function is constructed from shifting to other seven quadrants around a specific node of a basic isoparametric element in one quadrant and joining the corresponding node shape functions of eight elements at the specific *** MRA endows the proposed element with the resolution level(RL)to adjust structural analysis *** a result,the traditional 8-node hexahedron element is a monoresolution one and also a special case of the proposed *** meshing for the monoresolution finite element model is based on the empiricism while the RL adjusting for the multiresolution is laid on the solid mathematical *** simplicity and clarity of shape function construction with the Kronecker delta property and the rational MRA enable the proposed element method to be more rational,easier and efficient in its implementation than the conventional mono-resolution solid element method or other MRA *** multiresolution hexahedron element method is more adapted to dealing with the accurate computation of structural problems.

关键词： hexahedron element multiresolution analysis (MRA) resolution level (RL) basic node shape function mutually nesting displacement subspace sequence scaling and shifting

Regional features of pollen R-values in China

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Science China Earth Sciences 2024年第1期67卷 295-308页

作者： Jie xia Jian NI College of Life Sciences Zhejiang Normal UniversityJinhua 321004China Jinhua Mountain Observation and Research Station for Subtropical Forest Ecosystems Jinhua 321004China

Establishing a quantitative relationship between modern pollen and vegetation remains a pivotal but intricate pursuit within the field of Quaternary *** R-value,a well-established and traditional metric characterized by its simplicity and direct applicability,serves to calibrate the nonlinear disparities between surface pollen and modern *** study entails the construction of a comprehensive pollen R-value dataset for China derived from R-values published between 1987 and *** dataset,compiled after rigorous screening,calibration,and standardization processes,encompasses 898 modern pollen sampling sites and 2115 pollen R-value data entries,encapsulating 152 pollen taxa spanning 65 families and 113 *** the extracted R-values yielded the following insights:(1)A macrospatial analysis validates previously established knowledge at a site-specific ***,pollen R-value variations across China are statistically *** two-thirds of pollen taxa exhibit underrepresentation(e.g.,Taxodiaceae,Corylus,Nitraria,Tamarix,Cyperaceae,Poaceae,and Fabaceae),while the remaining one-third display overrepresentation(e.g.,Pinus,Picea,Betula,Ephedra,Chenopodiaceae,and Artemisia).The degree of underrepresentation surpasses that of overrepresentation,and the representation patterns of Castanea,Quercus,Polygonaceae,and Asteraceae are contingent upon vegetation types.(2)Pollen R-values follow distinct spatial distribution patterns within *** the woody vegetation region of eastern China,R-values progressively decline from north to south,correlating with rising temperatures and ***,in herbaceous vegetation regions of northern and western China,R-values decrease from east to west and from northeast to southwest,corresponding to increased ***,pollen R-values manifest variation contingent on pollen taxa,vegetation types,and climatic regions,even differing for the same taxa across varying

关键词： Pollen R-value Modern pollen-vegetation relationship Regional pattern Variability Paleovegetation reconstruction

Long-term trend in aerosol optical depth from 1980 to 2001 in north China

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Particuology 2008年第2期6卷 106-111页

作者： Jiangxia Xie xiangao xia College of Atmospheric Sciences Lanzhou University Lanzhou 730000 China Hunan Meteorological Bureau Changsha 410007 China LAGEO Institute of Atmospheric Physics Chinese Academy of Sciences Beijing 100029 China

Using the Total Ozone Mapping Spectrometer （TOMS） monthly aerosol optical depth （AOD） at 500 nm data from 1980 to 2001 in north China, the spatial and temporal variations of AOD were examined. Seasonal AODs in Taklimakan Desert were 0.69 and 0.44 in spring and summer, respectively, which were mainly due to frequent occurrences of dust events in this region. Dust activities in spring also led to high aerosol loading in Gobi Desert and in northeast China where spring AODs were 0.33 and 0.29, respectively. Heavily impacted by events such as volcano eruption, forest fires and extraordinary dust storms, AODs showed large inter-annual variations. A decreasing tendency in AOD was observed in north China during 1980-1991, though a reverse tendency was revealed during 1997-2001, especially for spring AOD in northeast China. Further study is required to figure out how much human activities have contributed to the AOD tendency in north China.

关键词： Total Ozone Mapping Spectrometer (TOMS) Aerosol optical depth (AOD) North China

Parametric study on supersonic flutter of angle-ply laminated plates using shear deformable finite element method

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Acta Mechanica Sinica 2011年第5期27卷 749-756页

作者： Wei xia Qiao Ni School of Civil Engineering and Mechanics Huazhong University of Science and Technology430074 Wuhan China MOE Key Laboratory for Strength and VibrationSchool of Aerospace Xi＇an Jiaotong University710049 Xi＇an China

The influence of fiber orientation,flow yaw angle and length-to-thickness ratio on flutter characteristics of angle-ply laminated plates in supersonic flow is studied by finite element *** structural model is established using the Reissner-Mindlin theory in which the transverse shear deformation is *** aerodynamic pressure is evaluated by the quasi-steady first-order piston *** equations of motion are formulated based on the principle of virtual *** the harmonic motion assumption,the flutter boundary is determined by solving a series of complex eigenvalue *** study shows that （1） The flutter dynamic pressure and the coalescence of flutter modes depend on fiber orientation,flow yaw angle and length-to-thickness ratio;（2） The laminated plate with all fibers aligned with the flow direction gives the highest flutter dynamic pressure,but a slight yawing of the flow from the fiber orientation results in a sharp decrease of the flutter dynamic pressure;（3） The angle-ply laminated plate with fiber orientation angle equal to flow yaw angle gives high flutter dynamic pressure,but not the maximum flutter dynamic pressure;（4） With the decrease of length-to-thickness ratio,an adverse effect due to mode transition on the flutter dynamic pressure is found.

关键词： Panel flutter Angle-ply laminates Fiber orientation Flow yaw angle Length-to-thickness ratio

A Hybrid Procedure for Finding Real Points on a Real Algebraic Set

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Journal of Systems Science & Complexity 2019年第1期32卷 185-204页

作者： WANG Yu xia Bican LMAM & School of Mathematical Sciences Peking University

Motivated by the idea of Shen, et al.'s work, which proposed a hybrid procedure for real root isolation of polynomial equations based on homotopy continuation methods and interval analysis,this paper presents a hybrid procedure to compute sample points on each connected component of a real algebraic set by combining a special homotopy method and interval analysis with a better estimate on initial intervals. For a real algebraic set given by a polynomial system, the new method ?rst constructs a square polynomial system which represents the sample points, and then solve this system by a special homotopy continuation method introduced recently by Wang, et al.(2017). For each root returned by the homotopy continuation method, which is a complex approximation of some(complex/real) root of the polynomial system, interval analysis is used to verify whether it is an approximation of a real root and ?nally get real points on the given real algebraic set. A new estimate on initial intervals is presented which helps compute smaller initial intervals before performing interval iteration and thus saves computation. Experiments show that the new method works pretty well on tested examples.

关键词： Homotopy continuation interval arithmetic polynomial system real variety

Memory-based adaptive event-triggered secure control of Markovian jumping neural networks suffering from deception attacks

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Science China(Technological Sciences) 2023年第2期66卷 468-480页

作者： YAO Lan HUANG xia College of Electrical Engineering and Automation Shandong University of Science and TechnologyQingdao 266590China

In this article,we study the secure control of the Markovian jumping neural networks(MJNNs)subject to deception *** the limitation of the network bandwidth and the impact of the deception attacks,we propose two memory-based adaptive event-trigger mechanisms(AETMs).Different from the available event-trigger mechanisms,these two memory-based AETMs contain the historical triggered data not only in the triggering conditions,but also in the adaptive *** can adjust the data transmission rate adaptively so as to alleviate the impact of deception attacks on the controlled system and to suppress the peak of the system *** view of the proposed memory-based AETMs,a time-dependent Lyapunov functional is constructed to analyze the stability of the error *** sufficient conditions to ensure the asymptotical synchronization of master-slave MJNNs are obtained,and two easy-to-implement co-design algorithms for the feedback gain matrix and the trigger matrix are ***,a numerical example is given to verify the feasibility and superiority of the two memory-based AETMs.

关键词： secure control memory-based adaptive event-trigger mechanism globally asymptotical synchronization deception attacks

Bullous pemphigoid associated with acquired hemophilia A: A case report

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World Journal of Clinical Cases 2025年第4期13卷 28-33页

作者： Su-Ye Hu Meng-Can Li Zi-Jia Hao Xu-Ya Chai Pei-Sai Li Yang Liu Li-xia Liu Ying Xu Pan-Pan Yang Ling-E Li Department of Dermatology Shijiazhuang Traditional Chinese Medicine HospitalShijiazhuang 050051Hebei ProvinceChina Graduate School Hebei University of Traditional Chinese MedicineShijiazhuang 050051Hebei ProvinceChina Department of Pathology Shijiazhuang Traditional Chinese Medicine HospitalShijiazhuang 050051Hebei ProvinceChina

BACKGROUND Acquired hemophilia A (AHA) is a rare and potentially severe bleeding disordercaused by circulating autoantibodies against factor Ⅷ (FⅧ). In approximately50% of the patients, the condition is associated with autoimmune diseases,cancers, medication use, pregnancy, and the post-partum period. Bullous pemphigoid(BP) is a chronic autoimmune subepidermal blistering disease associatedwith tissue-bound and circulating autoantibodies against BP antigens 180 (BP180)and 230 (BP230). AHA-associated BP has a high mortality rate;hence, the understandingof this disease must *** SUMMARY A 69-year-old man presented with erythema, blisters, blood blisters, and crustsaccompanied by severe pruritus for more than 20 days, and ecchymosis andswelling on his left upper arm for 3 days. Pathological examination revealed asubepidermal blister that contained eosinophils. Laboratory tests showed that theBP180 autoantibody levels had increased, isolated activated partial thromboplastintime was notably prolonged (115.6 s), and coagulation FⅧ activity wasextremely low (< 1.0%). Furthermore, the FⅧ inhibitor titer had greatlyincreased (59.2 Bethesda units). Therefore, the patient was diagnosed as having BP associated with AHA, prescribed 0.05% topical halometasone cream, and transferred to a higher-level hospitalfor effective treatment;however, he died after 2 *** AHA associated BP is rare, dangerous, and has a high mortality rate. Therefore, its timely diagnosis and effectivetreatment are necessary.

关键词： Bullous pemphigoid Acquired hemophilia A Acquired hemophilia A FactorⅧ Case report