检索结果-南通市图书馆

A theoretical and 1-d numerical investigation on a valve/valveless air-breathing pulse detonation engine

Chinese Journal of Aeronautics 2021年第1期34卷 68-78页

作者： Hua QIU cha XIONG Jianling LI School of Power and Energy Northwestern Polytechnical UniversityXi'an 710072China State Key Laboratory of Explosion Science and Technology Beijing Institute of TechnologyBeijing 100081China

The important operating characteristics of pulsed Pressure Gain Combustion(PGC)propulsion are the pressure gain of the combustor component and the propulsive performance gain of the engine.A ramjet-type valve/valveless air-breathing pulsed detonation engine with a supersonic internal compression inlet is *** on an ideal thermal cycle,the ideal equivalent pressure ratios(pcb)of the Pulsed detonation Combustor(PdC)are obtained theoretically which are directly related with the propulsive performance of the *** introducing an orifice loss model into the cycles,the critical pressure drop ratios through the orifice for the PdC achieving pressure gain and the engine achieving thrust gain are *** influencing factors are investigated by the use of a one-dimensional(1-d)numerical simulation *** operating characteristics of the pulse detonation engine are investigated with changes of the valve type,the inlet/outlet area ratio of the PdC,the nozzle area ratio,and flight *** these factors can affect pcbof the PdC,and pcbcan be optimized by changing the geometry of the *** most important influence parameter is the valve *** using an orifice-type aerodynamic valve,simulation results show that the PdC cannot achieve the pressure gain *** a supersonic internal compression inlet is introduced to the engine,whether the Pulse detonation Engine(PdE)can achieve thrust gain comparable with that of an ideal Brayton cycle engine not only is related to the pressure gain of the combustor,but also needs to optimize the engine structure to reduce the total pressure loss.

关键词： detonation Pressure gain characteristics Propulsive performance Supersonic internal compression inlet Valve/valveless Thermal cycle

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Parametric design of a part with free-form surfaces

引用

Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2006年第9期7卷 1530-1534页

作者： KIM Yeoung-il KIM Li-ra JUN cha-soo Reseach Institute for CAd/CAM CITEK System Changwon 641-845 Korea School of Industrial and Systems Engineering Gyeongsang National University Jinju 660-701 Korea Research Center for Aircraft Parts Technology School of Industrial and Systems Engineering Gyeongsang National University Jinju 660-701 Korea

3d solid models for parts with regular-form surfaces (PRFSs) are effectively generated using traditional parametric design techniques. A new model is obtained by changing some parameters defining the model. The parts with free-form surfaces (PFFSs), however, cannot be defined by several parameters. Usually they are defined by some geometric elements like profile curves. The traditional parametric design approaches have not easily dealt with the PFFSs. A method for generating a solid model and an engineering drawing for PFFSs is proposed in this paper: First, the new profiles are generated from input point data. Second, the profile information is extracted from the existing model. Last, the old profiles are replaced with the new profiles. This method can preserve the associative information of the existing model and automatically generate the drawing including views, dimen- sions, and annotations. The proposed method has been implemented using a commercial CAd/CAM system, Unigraphics, and API functions written in C-language, and were applied to the blades of a turbine generator. Some illustrative examples are pro- vided in order to show the effectiveness of the proposed method.

关键词： Parametric modelling Free-form surface Solid model drawing

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Pan-TRK positive uterine sarcoma in immunohistochemistry without neurotrophic tyrosine receptor kinase gene fusions:A case report

引用

World Journal of Clinical Cases 2025年第2期13卷 39-49页

作者： Seungmee Lee Yu-ra Jeon changmin Shin Sun-Young Kwon Sojin Shin department of Obstetrics and Gynecology Keimyung University School of MedicineDaegu 42601South Korea department of Pathology and Institute for Cancer Research Keimyung University School of MedicineDaegu 42601South Korea

BACKGROUNd The classification of uterine sarcomas is based on distinctive morphological and immunophenotypic characteristics,increasingly supported by molecular genetic *** on neurotrophic tyrosine receptor kinase(NTRK)gene fusionpositive uterine sarcoma,potentially aggressive and morphologically similar to fibrosarcoma,are limited due to its recent ***-TRK immunohistochemistry(IHC)analysis serves as an effective screening tool with high sensitivity and specificity for NTRK-fusion *** SUMMARY We report a case of a malignant mesenchymal tumor originating from the uterine cervix,which was pan-TRK IHC-positive but lacked NTRK gene fusions,accompanied by a brief literature review.A 55-year-old woman presented to the emergency department with abdominal pain and distension,exhibiting significant ascites and multiple solid pelvic *** examination revealed a tumor encompassing the uterine cervix,extending to the vagina and uterine corpus.A punch biopsy of the cervix indicated NTRK sarcoma with positive immunochemical pan-TRK ***,subsequent next generation sequencing revealed no NTRK gene fusion,leading to a diagnosis of poorly differentiated,advanced-stage *** The clinical significance of NTRK gene fusion lies in potential treatment with TRK inhibitors for positive *** such rare tumors is crucial due to the potential applicability of tropomyosin receptor kinase inhibitor treatment.

关键词： Uterine sarcoma Cervical sarcoma Neurotrophic tyrosine receptor kinase gene fusion Next generation sequencing Case report

来源：

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

Biochemical dissection of STAT3 signaling in amyotrophic lateral sclerosis

引用

Neural Regeneration Research 2025年第11期20卷 3229-3230页

作者： Savina Apolloni Nadia d’Ambrosi department of Biology University of Rome Tor VergataRomeItaly

Amyotrophic lateral sclerosis(ALS)is a progressive neurodegenerative disease characterized by the loss of upper and lower motor neurons,clinically marked by muscle atrophy and *** the clinical course is highly variable,the average time from the onset of symptoms to the need for respiratory support or death is 3-5 *** is the most prevalent motor neuron disease in adults,occurring at a rate of 2 per 100,000 individuals and affecting 5.4 per 100,000 individuals overall.

关键词： STAT3 dissection sclerosis

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Anti-amyloid antibodies in Alzheimer’s disease: what did clinical trials teach us?

引用

Neural Regeneration Research 2025年第4期20卷 1092-1093页

作者： danko Jeremic Lydia Jiménez-díaz Juan d.Navarro-López NeuroPhysiology&Behavior Lab University of Castilla-La ManchaBiomedical Research Center(CRIB)School of Medicine of Ciudad RealCiudad RealSpain

Although many causes of Alzheimer’s disease(Ad)may exist,both the original amyloid cascade and tau hypotheses posit that abnormal misfolding and accumulation of amyloid-β(Aβ)and tau protein is the central event causing the ***,that conclusion could be only partly true,and there is conflicting evidence about the role of both proteins in Ad,being able to precede and influence one *** researchers argue that these proteins are mere executors rather than primary causes of ***,there have been continuing refinements of both hypotheses,with alternative explanations proposed.Aβand tau proteins may be independently involved in specific neurotoxic pathways;yet there may be other crucial processes going on in early ***,accumulating evidence suggests that Aβand tau act synergistically,rather than additively in disease onset(Jeremic et al.,2021,2023a).

关键词： amyloid Alzheimer additive

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Remaking a connection:molecular players involved in post-injury synapse formation

引用

Neural Regeneration Research 2025年第6期20卷 1719-1720页

作者： diogo Tomé ramiro d.Almeida iBiMEd-Institute of Biomedicine Department of Medical SciencesUniversity of AveiroAveiroPortugal CNC-Center for Neuroscience and Cell Biology University of CoimbraCoimbraPortugal

Functional recovery from central nervous system(CNS)trauma depends not only on axon regeneration or compensatory sprouting of uninjured fibers but also on the ability of newly grown axons to establish functional synapses with appropriate *** several studies have successfully promoted long-distance axonal regeneration in distinct CNS injury models,none of them have resulted in a viable therapeutic approach for patient recovery.A possible reason may be the lack of new synaptogenesis for reestablishing the circuitry lost after ***,we discuss how our understanding of the mechanisms that instruct synapse formation in the injured nervous system may contribute to the design of new strategies to promote functional restoration in traumatic CNS disorders.

关键词： viable injury instru

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Alleviating vibrations along a harmonically driven nonuniform Euler-Bernoulli beam by imposing nodes

引用

International Journal of Mechanical System dynamics 2023年第4期3卷 345-359页

作者： Melis Baltan‐Brunet Fionna Kopp Philip d.cha department of Engineering Harvey Mudd CollegeClaremontCaliforniaUSA

A passive approach is developed to quench excess vibration along a harmonically driven,arbitrarily supported,nonuniform Euler-Bernoulli beam with constant thickness(height)and varying *** suppression is achieved by attaching properly tuned vibration absorbers to enforce nodes,or points of zero vibration,along the *** efficient hybrid method is proposed whereby the finite element method is used to model the nonuniform beams,and a formulation based on the assumed modes method is used to determine the required attachment force supplied by each absorber to induce the desired *** the attachment forces needed to induce nodes,design plots are generated for the absorber parameters as a function of the tolerable vibration amplitude for each absorber *** the node locations are judiciously chosen,it is possible to dramatically suppress the vibration along a selected region of the *** such,sensitive instruments can be placed in this region and will remain nearly *** studies illustrate the application to several systems with various types of nonuniformity,boundary conditions,and attachment and node locations;these examples validate the proposed method to passively control excess vibration by inducing nodes on nonuniform beams subjected to harmonic excitations.

关键词： vibration suppression nonuniform beam vibration absorber finite element enforcing nodes

来源：

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

Enhanced thermoelectric performance of spark plasma sintered p-type Ca_(3-x)Y_(x)Co_(4)O_(9+δ)systems

引用

Journal of Materials Science & Technology 2020年第20期52卷 212-222页

作者： J.S.cha d.H.Kim H.Y.Hong K.Park Faculty of Nanotechnology and Advanced Materials Engineering Sejong UniversitySeoul05006Republic of Korea

Highly textured dense Ca3-xYxCo4 O9+δ(0≤x≤0.3)samples were fabricated by combining sol-gel process with spark plasma sintering(SPS).Y^3+substitution for Ca^2+simultaneously increased the Seebeck coefficient and reduced the thermal *** latter was attributed to the increase in lattice anharmonicity,structural distortion,and grain boundary area,which enhanced the phonon ***2.7Y0.3Co4 O9+δshowed the largest dimensionless figure-of-merit(ZT=0.194)at 1073 K because it had the largest Seebeck coefficient and the lowest thermal *** ZT value was 55%larger than that of undoped Ca3 Co4 O9(0.125 at 1073 K).Therefore,Y^3+substitution,sol-gel powder synthesis,and SPS are highly effective for enhancing the thermoelectric prope rties of Ca_(3)Co_(4)O_(9).

关键词： Electrical conductivity Ca_(3)Co_(4)O_(9) Thermoelectric properties Seebeck coefficient Thermal conductivity Spark plasma sintering

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Effects of structure and electronic properties of d-π-A organic dyes on photovoltaic performance of dye-sensitized solar cells

引用

Journal of Energy Chemistry 2021年第3期30卷 208-216页

作者： Min-Woo Lee Jae-Yup Kim Hyung-Geun Lee Hyun Gil cha duck-Hyung Lee Min Jae Ko Bio-Based Chemistry Research Center Advanced Convergent Chemistry DivisionKorea Research Institute of Chemical Technology(KRICT)Ulsan 44429Republic of Korea department of Chemical Engineering Dankook UniversityYongin 16890Republic of Korea department of Chemistry Sogang UniversitySeoul 04107Republic of Korea department of Chemical Engineering Hanyang UniversitySeoul 04763Republic of Korea Institute of Nano Science and Technology Hanyang UniversitySeoul 04763Republic of Korea

Herein,we examine the performance of dye-sensitized solar cells containing five d-π-A organic dyes designed by systematic modification of π-bridge size and geometric *** dye has a simple push-pull structure with a triarylamino group as an electron donor,bithiophene-4,4-dimethyl-4 H-cyclopenta 1,2-b:5,4-b’]dithiophene(M11),4,4-dimethyl-4 H-cyclopenta[1,2-b:5,4-b’]dithiophenethiophene(M12),thiophene-4,4-dimethyl-4 H-cyclopenta[1,2-b:5,4-b’]dithiophene(M13),4,4-dimethyl-4 H-cyclopenta[1,2-b:5,4-b’]dithiophene-benzene(M14),and 4,4-dimethyl-4 H-cyclopenta[1,2-b:5,4-b’]dithiophene(M15)units asπ-bridges,and cyanoacrylic acid as an electron acceptor/*** extension of theπ-bridge linkage favors wide-range absorption but,because of the concomitant molecular volume increase,hinders the efficient adsorption of dyes on the TiO_(2) film ***,higher loadings are achieved for smaller dye molecules,resulting in(i)a shift of the TiO_(2) conduction band edge to more negative values,(ii)a greater photocurrent,and(iii)suppressed charge recombination between the photoanode and the redox couple in the ***,under one-sun equivalent illumination(AM 1.5 G,100 mW/cm^(2)),the highest photovoltage,photocurrent,and conversion efficiency(η=7.19%)are observed for M15,which has the smallest molecular volume among M series dyes.

关键词： dye-sensitized solar cells donor-acceptor dyes Electron-rich unit Wide-range absorption Impedance spectroscopy

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Multifunctional SnO2/3d graphene hybrid materials for sodium-ion and lithium-ion batteries with excellent rate capability and long cycle life

引用

Nano Research 2017年第12期10卷 4398-4414页

作者： Jung-ln Lee Junhua Song Younghwan cha Shaofang Fu Chengzhou Zhu Xiaolin Li Yuehe Lin Min-Kyu Song School of Mechanical and Materials Engineering Washington State University Pullman WA 99164 USA Energy & Environment directorate Pacific North west National Laboratory Richland WA 99352 USA Pacific Northwest National Laboratory Richland WA 99352 USA

SnO2 is a promising material for both Li-ion and Na-ion batteries owing to its high theoretical capacities. Unfortunately, the electrochemical performance of SnO2 is unsatisfactory because of the large volume change that occurs during cycling, low electronic conductivity of inactive oxide matrix, and poor kinetics, which are particularly severe in Na-ion batteries. Herein, ultra-fine SnO2 nanocrystals anchored on a unique three-dimensional （3d） porous reduced graphene oxide （rGO） matrix are described as promising bifunctional electrodes for Li-ion and Na-ion batteries with excellent rate capability and long cycle life. Ultra-fine SnO2 nanocrystals of size -6 nm are well-coordinated to the graphene sheets that comprise the 3d macro-porous structure. Notably, superior rate capability was obtained up to 3 C （1In C is a measure of the rate that allows the cell to be charged/discharged in n h） for both batteries. In situ X-ray diffractometry measurements during lithiation （or sodiation） and delithiation （or desodiation） were combined with various electrochemical techniques to reveal the real-time phase evolution. This critical information was linked with the internal resistance, ion diffusivity （dLi＋ and dNa＋）, and the unique structure of the composite electrode materials to explain their excellent electrochemical performance. The improved capacity and superior rate capabilities demonstrated in this work can be ascribed to the enhanced transport kinetics of both electrons and ions within the electrode structure because of the well-interconnected, 3d macro-porous rGO matrix. The porous rGO matrix appears to play a more important role in sodium-ion batteries （SIBs）, where the larger mass/radius of Na-ions are marked concerns.

关键词： sodium-ion batteries (SIBs) lithium-ion batteries (LIBs) SnO2 three-dimensional (3d)graphene hybrid materials

来源：

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

欢迎您,

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案：

请选择收藏分类：

通借通还

欢迎您,

建议与咨询 留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案： 新增检索档案 确定 取消

请选择收藏分类： 新增自定义分类 确定 取消

通借通还

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

请选择保存的检索档案：

请选择收藏分类：