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橡胶参考资料 1993年第7期23卷 57-60页

作者： Dan Forsstrom Anna Kron bengt mattson 蔡善同

前言早在1605年弗郎西斯贝根已报导过摩擦荧光现象,他指的是在黑暗中摩擦蔗糖能使之发光。摩擦荧光的定义是由于摩擦电荷使表面间隙产生的发光现象。荧光可由许多不同的反应来产生。

关键词：橡胶化学荧光老化

Effect of Shape and Placement of Twisted Pin Fins in a Rectangular Channel on Thermo-Hydraulic Performance

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Journal of Thermal Science 2024年第5期33卷 1773-1793页

作者： LI Yong ZHANG Jin ZHANG Yingchun ZHANG Jiajie MA Suxia SUNDEN bengt XIE Gongnan College of Electrical and Power Engineering Taiyuan University of TechnologyTaiyuan 030024China Key Laboratory of Cleaner Intelligent Control on Coal&Electricity Ministry of EducationTaiyuan 030024China Shanxi Provincial Key Laboratory of High Efficiency Heat Storage and Low Carbon Heat Supply Taiyuan 030008China School of Energy and Power Engineering North University of ChinaTaiyuan 030051China Department of Energy Sciences Lund UniversityP.O.Box 118Lund SE 22100Sweden School of Marine Science and Technology Northwestern Polytechnical UniversityXi'an 710072China

To enhance the thermo-hydraulic performance of cooling channels,this investigation examines the influence of distinct cross-sectional shapes(i.e.,triangular,rectangular,and hexagonal)of twisted pin fins and their arrangements in straight and cross *** ambient air cooling test platform was established to numerically and experimentally investigate the flow and heat transfer characteristics of 360°twisted pin fins at Re=*** findings reveal that straight rows exhibit higher Nu values than cross rows for triangular and rectangular twisted pin fins,and Nu increases with *** contrast,for hexagonal twisted pin fins,only straight rows at Re=19000 exhibit superior overall thermal performance compared to cross ***,the heat transfer performance of the cooling channel with hexagonal twisted fins surpasses both triangular and rectangular configurations,especially at high Reynolds numbers(Re=22800).Although the heat transfer coefficient of the cooling channel with hexagonal twisted fins is significantly enhanced by 132.71%compared to the flat channel,it also exhibits the highest thermal resistance and relative friction among the three types of twisted fins,the maximum of which are 2.14 and ***,the hydrothermal performance factor(HTPF)of the cooling channels with different types of twisted pin fins depends on the Reynolds number and arrangement *** Re=15200,the highest HTPF achieved for the cross-row hexagonal twisted pin fins is 0.99.

关键词： twisted pin fin cross arrangement heat transfer pressure drop HTPF

Recent Development of Heat Transfer and Fluid Flow of Supercritical CO2 in Tubes:Mechanisms and Applications

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Journal of Thermal Science 2024年第6期33卷 2274-2298页

作者： ZHANG Xirui SHAO Qihan LIU Jian XI Wenxiong LIU Chaoyang SUNDEN bengt Research Institute of Aerospace Technology Central South University College of Aerospace Science and Engineering National University of Defense Technology Department of Energy Sciences Lund University

With the advantages of low cost,excellent ability of heat and mass transfer and easy accessibility to the supercritical point,supercritical CO2has been applied in many engineering devices *** of the sharply-varying thermophysical properties near the supercritical point,heat transfer and flow behavior of supercritical CO2in tubes become complex and have received a lot of research *** main purpose of this paper is to summarize the findings of the published works related to flow phenomena and heat transfer characteristics of supercritical ***,influence parameters related to boundary conditions of supercritical CO2flowing in a smooth tube are ***,commonly-used turbulence and mathematic models dealing with internal flows of supercritical CO2are ***,research works on geometric effects of design parameters,shapes and configurations are *** practical applications of supercritical CO2in recent years are ***,developments and future challenges of supercritical CO2in tubes are analyzed and *** paper provides basic knowledge of heat transfer and fluid flow mechanisms and related practical applications of supercritical CO2in tubes.

关键词： developments and challenges flow behavior heat transfer practical applications supercritical CO2

Investigation of Interacting Mechanism between Film Cooling and Internal Cooling Structures of Turbine Blade

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Journal of Thermal Science 2023年第1期32卷 330-350页

作者： ZHANG Guohua XIE Gongnan bengt Sundén School of Marine Science and Technology Northwestern Polytechnical UniversityXi'an 710072China School of Mechanical Engineering Northwestern Polytechnical UniversityXi'an 710072China Department of Energy Sciences Lund UniversityLund SE-22100Sweden Research&Development Institute of Northwestern Polytechnical University in Shenzhen Shenzhen 518057China

This paper presents three-dimensional numerical simulations with the established realizable k-εmodel to clarify the underlying and interacting mechanisms between the film cooling and the internal *** the one hand,the effects of three different internal cooling channels,i.e.,smooth channel,continuous ribbed channel,and truncated ribbed channel,on the film cooling effectiveness and the discharge coefficients are *** the other hand,the influences of three different film cooling holes,i.e.,cylindrical hole,two elliptical holes and two circular-to-elliptical holes,on the heat transfer performances and pressure loss of the internal cooling channel are ***,the suction effects of the film cooling holes are analyzed through setting up baselines with only internal cooling *** show that the placement of ribs in the internal channel has different influences on the film cooling effectiveness with respect to different hole shapes depending on the blowing *** discharge coefficient of the film hole can be improved by introducing ribs to the internal *** of film hole is helpful for enhancing the heat transfer performance and reducing the pressure loss of the internal ***,ribs instead of the suction effect of film hole play a major role to enhance the heat transfer performance in the internal cooling channel.

关键词： interacting mechanism film cooling effectiveness discharge coefficient heat transfer performance pressure drop

MAGNETIC FIELD EFFECT ON PHOTOPOLYMERIZATION OF STYRENE MICROEMULSION

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Chinese Journal of Polymer Science 1993年第1期11卷 1-7页

作者：陈用烈 Anders Hult bengt Ranby Institute of Polymer Science Zhongshan University Guangzhou Department of Polymer Technology The Royal Institute of Technology Stockholm Sweden

External magnetic field increases the photo-induced polymerization rate of styrene *** type of photoinitiator plays an important role. The photoinitiators, used are dimethoxyphenyl acetophenone(DMPA), 1-hydroxycyclohexyl phenylketone (Irgacure 184) and dimethylhydroxyacetophenone (Darocur 1173). No magnetic effect was observed by using dibenzylketone (DBK) as photoinitiator. The molecular weight of the polymer is slightly affected by magnetic field. The influence of temperature has also been investigated.

关键词： DMPA MAGNETIC FIELD EFFECT ON PHOTOPOLYMERIZATION OF STYRENE MICROEMULSION

Comparisons of Heat Transfer Enhancement of an Internal Blade Tip with Metal or Insulating Pins

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Advances in Applied Mathematics and Mechanics 2011年第3期3卷 297-309页

作者： Gongnan Xie bengt Sunden The Key Laboratory of Contemporary Design and Integrated Manufacturing Technology Northwestern Polytechnical UniversityXi’an 710072ShaanxiChina Division of Heat Transfer Lund UniversitySE-22100LundSweden

Cooling methods are needed for turbine blade tips to ensure a long durability and safe operation.A common way to cool a tip is to use serpentine passages with 180-deg turn under the blade tip-cap taking advantage of the threedimensional turning effect and impingement like *** internal convective cooling is therefore required to increase the blade tip *** the present study,augmented heat transfer of an internal blade tip with pin-fin arrays has been investigated numerically using a conjugate heat transfer *** computational domain includes the fluid region and the solid pins as well as the tip *** convective heat transfer between the fluid and pins,and heat conduction within pins and tip are simultaneously *** main objective of the present study is to observe the effect of the pin material on heat transfer enhancement of the pin-finned *** is found that due to the combination of turning,impingement and pin-fin crossflow,the heat transfer coefficient of a pin-finned tip is a factor of 2.9 higher than that of a smooth tip at the cost of an increased pressure drop by less than 10%.The usage of metal pins can reduce the tip temperature effectively and thereby remove the heat load from the ***,it is found that the tip heat transfer is enhanced even by using insulating pins having low thermal conductivity at low Reynolds *** comparisons of overall performances are also included.

关键词： Heat transfer enhancement tip-wall pins thermal conductivity weight

Gut microbiota and surgical disease

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Hepatobiliary Surgery and Nutrition 2018年第1期7卷 32-33页

作者： bengt Jeppsson Department of Surgery Lund UniversityLundSweden

Why should surgeons study gut microbiota and microbiome(totality of body's microorganisms and genomes)?There are at least three reasons.

关键词： surgical reasons surgeon

Effects of Ribbed-Cavity Tip on the Blade Tip Aerothermal Performance in a High Pressure Turbine Stage

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Journal of Thermal Science 2023年第2期32卷 800-811页

作者： DU Kun LI Huarong SUNDEN bengt LIU Cunliang School of Power and Energy Northwestern Polytechnical UniversityXi'an 710072China Yangtze River Delta Research Institute of NPU Northwestern Polytechnical UniversityTaicang 215400China Shaanxi Key Laboratory of Thermal Sciences in Aero-Engine System Northwestern Polytechnical UniversityXi'an 710129China NPU-KAI International Joint Laboratory of Advanced Aero-Engine Thermal Structure Northwestern Polytechnical UniversityXi'an 710129China Division of Heat Transfer Department of Energy SciencesLund UniversityLund SE-22100Sweden

For unshrouded blade tip,the high-temperature gas flows through the tip clearance by force of the lateral pressure ***,the blade tip endures increasing thermal ***,the conventional blade tip treatment cannot continuously provide protection for the deteriorating service *** the present study,aerothermal characteristics of the squealer blade tip with staggered ribs,partial squealer rim and different partial squealer rim thickness were investigated to explore the influences of ribbed-cavity tip on the tip heat transfer,leakage flow and turbine stage *** numerical results indicate that the ribbed-cavity tips are beneficial for the reduction of the blade tip thermal load and leakage *** the present six blade tip designs,the minimal area-averaged heat transfer coefficient is obtained by the case with the staggered ribs and a deeper squealer rim,which is reduced by 31.41%relative to the squealer ***,the blade tip modification closer to leading edge or tip mid-chord region performs better than trailing edge in reducing the tip leakage flow.

关键词： gas turbine tip leakage flow numerical simulation blade tip configuration

Hip prosthetic loosening:A very personal review

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World Journal of Orthopedics 2021年第9期12卷 629-639页

作者： bengt Mjöberg Department of Orthopedics Lund UniversityLund SE-22100Sweden

Hip prosthetic loosening is often difficult to detect at an early stage,and there has been uncertainty for a long time as to when the loosening occurs and thus to the basic *** comparing different diagnostic methods,we found that loosening is best defined as prosthetic migration and measured by radiostereometric *** evidence indicates that poor interlock,poor bone quality,and resorption of a necrotic bone bed may initiate loosening during or shortly after surgery;this forms the basis of the theory of early *** factors do affect the subsequent progression of loosening,which may increase subclinically during a long period of ***,the loosening may be detected on standard radiographs and may be interpreted as late loosening but should to be interpreted as late detection of *** theory of early loosening explains the rapid early migration,the development of periprosthetic osteolysis and granulomas,the causality between wear and loosening,and largely the epidemiology of clinical failure of hip *** discussed are definition of loosening,the pattern of early migration,the choice of migration threshold,the current understanding of loosening,a less exothermic bone cement,cemented taper-slip stems,a new exciting computed tomography-based technique for simpler implant migration studies,and research suggestions.

关键词： Hip prosthesis Prosthesis failure Radiostereometric analysis Bone resorption Bone cements Radionuclide imaging

WAVELET ANALYSIS IN THE TIME-FREQUENCY SPECTRUM FOR SOME NONLINEAR WAVES OBSERVED BY FREJA SATELLITE

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紫金山天文台台刊 1998年第2期 101-108页

作者： bengt Holback Swedish Institute for Space Physics Uppsala Sweden

Some new nonlinear plasma waves at the local ion gyrofrequencies or low-hybrid frequency observed by Freja satellite in low aurora( 1700km) are reported and analyzed with the wavelet transformation in the time-frequency spectrum, especially, the multi-frequency structures and their time evolution. Hence, the wavelet transformation may be a powerful method to study the time-frequency fine structures.

关键词：天文台紫金山卫星观测光力频率谱非线性波小波分析作时气田二氨