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浅析舒伯特《冬之旅》——《凝结》的音乐风格
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作者 吴思里 《艺术科技》 2020年第21期113-114,共2页
作为浪漫主义时期的代表人物之一,舒伯特的音乐继承了古典主义时期音乐的风格,又是浪漫主义时期音乐的开拓者,他的作品十分丰富,舒伯特在一生的最后两年创作出了一部重要的代表作,即声乐套曲《冬之旅》。本文选取《冬之旅》中的第四首... 作为浪漫主义时期的代表人物之一,舒伯特的音乐继承了古典主义时期音乐的风格,又是浪漫主义时期音乐的开拓者,他的作品十分丰富,舒伯特在一生的最后两年创作出了一部重要的代表作,即声乐套曲《冬之旅》。本文选取《冬之旅》中的第四首《凝结》,从旋律、和声等方面进行分析。 展开更多
关键词 舒伯特 《冬之旅》 《凝结》 和声 钢琴伴奏
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Development of a Thermal Fogger-specific Sedimentation Stabilizer 被引量:1
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作者 苏贤岩 何薇薇 +4 位作者 任学祥 陈莉 丁克坚 胡飞 叶正和 《Agricultural Science & Technology》 CAS 2017年第6期1120-1125,共6页
In order to solve the drifting away of thermal fog droplets during thermal spraying and the incompatibility between fog droplet carrier and conventional com- mercial agro-chemicals, the fog droplet carrier, surfactant... In order to solve the drifting away of thermal fog droplets during thermal spraying and the incompatibility between fog droplet carrier and conventional com- mercial agro-chemicals, the fog droplet carrier, surfactant, condensation nucleus ma- terial and antifreeze, dispersant, thickener and defoamer were screened and assem- bled to develop a thermal fog sedimentation stabilizer in this study, thereby provid- ing technical support for application and promotion of thermal spraying technology in pest and disease control in crops. 展开更多
关键词 Thermal fogger Sedimentation stabilizer Fogging carrier SURFACTANT Condensation nucleus material
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Practice and analysis of recycling non-drinking water from air-condition and reverse-osmosis system into rainwater collection system 被引量:2
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作者 王小红 邵煜然 王靖华 《Journal of Southeast University(English Edition)》 EI CAS 2014年第2期169-174,共6页
This paper is based on the rainwater collection project in the retrofit of the Dongyi teaching block in Zhejiang University Xixi Campus.The analysis incorporates the local meteorological data, recycling water utilizat... This paper is based on the rainwater collection project in the retrofit of the Dongyi teaching block in Zhejiang University Xixi Campus.The analysis incorporates the local meteorological data, recycling water utilization, and precipitation adjustment.The rainwater collection system in this program also adds the condensation water from the heating, ventilation and air conditioning ( HVAC) system and the concentration from the reverse-osmosis system used for watering greens and supplying waterscapes.By calculating, the quantity of the HVAC condensation water in summer is 3.48 m3/d, and the quantity of the reverse-osmosis concentrated water is 198 to 396 L/d.This method solves the water shortage caused by high evaporation in summer and low precipitation in winter.Supported by empirical monitoring data, the proposed method significantly increases the economic efficiency of the system during the summer period. 展开更多
关键词 rainwater collection heating ventilation and air conditioning condensation water precipitation analysis reverse-osmosis concentrated water
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Roles of Zr and Y in cast microstructure of M951 nickel-based superalloy 被引量:6
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作者 周鹏杰 于金江 +2 位作者 孙晓峰 管恒荣 胡壮麒 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2012年第7期1594-1598,共5页
The influence of Zr and Y on the cast microstructure of a nickel-based superalloy was investigated by optical microscopy (OM),scanning electron microscopy(SEM),electron probe micro-analysis(EPMA)and X-ray diffra... The influence of Zr and Y on the cast microstructure of a nickel-based superalloy was investigated by optical microscopy (OM),scanning electron microscopy(SEM),electron probe micro-analysis(EPMA)and X-ray diffraction(XRD).Theγ+γ′eutectic volume in the superalloy rises notably with the increase of Zr or Y content.Meanwhile,the morphologies of primary MC carbides change from needle and platelet-like to blocky shape with increasing Zr and Y doped.The XRD results show that the primary MC carbide lattice constant increases with Zr and Y additions,and EPMA investigation shows that the platelet-like MC carbides contain primarily Nb and C,while those carbides in blocky shape have 39.2%Zr and 39.6%Nb in average,.These influences on the cast microstructure can be attributed to the atomic size effects of Zr and Y. 展开更多
关键词 YTTRIUM ZIRCONIUM carbides nickel based superalloys MICROSTRUCTURE SOLIDIFICATION
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Durability design of prestressed concrete structures 被引量:4
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作者 涂永明 吕志涛 《Journal of Southeast University(English Edition)》 EI CAS 2005年第1期73-77,共5页
Based on the durability characteristics of prestressed concrete structures,the durability limit states of carbonation and chloride ion attack are defined, respectively.Durability predicting models on the basis of reli... Based on the durability characteristics of prestressed concrete structures,the durability limit states of carbonation and chloride ion attack are defined, respectively.Durability predicting models on the basis of reliability mathematics and stochastic processes areconstructed, and the pure theoretical formulae of failure probability of prestressed concretestructures are analyzed. In addition, a simple durability design method for carbonation ofstructures is put forward. According to the analysis, the durability of prestressed concretestructures is superior to that of traditional structures. The research also indicates that theconcrete cover prescribed in the current code (GB 50010-2002) is not adequate. The rational coverthickness should notbe less than 35 or 45 mm according to carbonation or chloride ion attack,respectively. 展开更多
关键词 prestressed concrete structure limit state failure probability durabilitydesign
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Durability zonation standard of concrete structure design 被引量:5
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作者 金伟良 吕清芳 《Journal of Southeast University(English Edition)》 EI CAS 2007年第1期98-104,共7页
Durability zonation standard (DZS) is proposed to provide useful parameters for durable concrete structure design. It deals not only with the influence of environment on structures, but also with types, functions an... Durability zonation standard (DZS) is proposed to provide useful parameters for durable concrete structure design. It deals not only with the influence of environment on structures, but also with types, functions and importance of structures based on the theory of life cycle cost(LCC). First, the basic concept of DZS for concrete structure design is defined. Then the basic principles for DZS are established. The factors for zonation according to natural environmental conditions and structural importance are identified. The usefulness of DZS by citing a real application for concrete highway bridges in Zhejiang Province is demonstrated. Finally, durability regulations are provided accordingly to zonation. 展开更多
关键词 durability zonation standard concrete structure design zonation map life cycle cost
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Measurement and theoretical analysis of solar temperature field in steel-concrete composite girder 被引量:5
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作者 陈晓强 刘其伟 朱俊 《Journal of Southeast University(English Edition)》 EI CAS 2009年第4期513-517,共5页
The solar temperature field of a large three-span continuous bridge with steel-concrete composite box girder and variable cross-section is measured to verify a calculation method for the temperature field of steel-con... The solar temperature field of a large three-span continuous bridge with steel-concrete composite box girder and variable cross-section is measured to verify a calculation method for the temperature field of steel-concrete composite beams. The test results show that the temperature of an external steel web- plate is higher than that of an internal web-plate due to the difference in solar radiation. Air temperature inside the box matches the average temperature of the whole steel box. Based on actual measurements, a transient thermal analysis with multiple boundary conditions is also carried out by a software program ANSYS. Convective boundary situation and states of solar radiation on steel web plates in different situations are determined in the analysis. The feature of the temperature field is preliminarily achieved through a comparative study between the actual measurement and the finite element analysis. The computed results are in good consistence with the actual measurement results, with the maximum difference within 2 ℃. This indicates that the theoretical calculation method is reliable and it provides a foundation for further research on temperature field distribution in the steel-concrete composite box girder. 展开更多
关键词 steel-concrete composite structure: solar radiation: temperature field EXPERIMENT
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Application of laminated vierendeel truss in high-position transfer story structure 被引量:8
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作者 戴国亮 童小东 +1 位作者 黄祥海 梁书亭 《Journal of Southeast University(English Edition)》 EI CAS 2005年第2期184-190,共7页
To meet the demands for large space and flexible compartmentation ofbuildings, laminated vierendeel trasses are adopted in high-position transfer story structures.First the bearing characteristics are analyzed, in whi... To meet the demands for large space and flexible compartmentation ofbuildings, laminated vierendeel trasses are adopted in high-position transfer story structures.First the bearing characteristics are analyzed, in which reasonable stiffness ratio of the upperchord, middle chord, and lower chord is derived. Then combined with an actual engineering model (1:8similar ratio), the static loading and pseudo-dynamic tests of two models for laminated vierendeeltrass used in transfer story structures are conducted, in which one model adopts reinforcedconcrete, and the other adopts prestressed concrete and shape steel concrete. Seismic behaviors areanalyzed, including inter-story displacement, base shear-displacement skeleton curves, andequivalent viscosity-damping curves. A program is programmed to carry out the elasto-plastic dynamicanalysis, and displacement time-history curves of the two models are derived. The test and analysisresults show that the laminated vierendeel trass with prestressed concrete and shape steel concretehas excellent seismic behaviors. It can solve the disadvantages of laminated vierendeel trussesused in transfer story structures. Finally, some design suggestions are put forward, which can bereferenced by similar engineering. 展开更多
关键词 laminated vierendeel trass steel concrete transfer story structure prestressed concrete elastro-plasticity analysis
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Structural Analysis and Anticoagulant Activity of Polysaccharides from Opuntia milpa alta 被引量:1
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作者 蔡为荣 谢亮亮 +1 位作者 陶鹏飞 崔武卫 《Agricultural Science & Technology》 CAS 2012年第2期255-260,264,共7页
[Objective] To analyze the components and structure of Opuntia milpa alta polysaccharides, and to study its anticoagulant activity. [Method] The crude polysaccharides (CP) were prepared from Opuntia milpa alta using... [Objective] To analyze the components and structure of Opuntia milpa alta polysaccharides, and to study its anticoagulant activity. [Method] The crude polysaccharides (CP) were prepared from Opuntia milpa alta using hot water extraction and ethanol precipitation method, purified by anion-exchange chromatography and gel filtration chromatography to study its monosaccharide composition, weight-average molecular weight distribution and main chain structure. And a preliminary study was conducted on the anticoagulant activity of polysaccharide components. [Result] The polysaccharide components WSP1, WSP2a and WSP3 were obtained from CP by the anion-exchange chromatography and gel filtration chromatography. WSP1 was mainly composed of galactose with a weight-average molecular weight of 2.32×106. WSP2a consisted of rhamnose, arabinose, xylose, mannose, glucose, galactose, glucuronic acid and galacturonic acid, the contents were 6.3%, 32.3%, 12.9%, 1.5%, 4.8%, 37.1%, 0.64% and 4.4%, respectively. WSP3 mainly composed of arabinose, xylose, rhamnose and trace of glucose, mannose, uronic acid. The weight-average molecular weight of WSP2a and WSP3 was 1.24×106 and 7.92×106, respectively. WSP2 prolonged the activated partial thromboplatin time (APTT) and thrombin time (TT), while had no significant effect on the prothrombin time (PT) in vitro, indicating that anticoagulant activity of WSP2 functions by affecting the intrinsic coagulation system. The test of inhibition to the conversion of fibrinogen into thrombin showed that WSP2a and WSP3 had obvious anticoagulant activity. Methylation analysis indicated that the main chain of WSP2a was constituted of 1, 4-GalA, 1, 2-Rha and 1, 2, 4-Rha. [Conclusion] This study provided experimental basis for the optimization and development of polysaccharide resources from cactus 展开更多
关键词 Opuntia milpa alta ANTICOAGULATION Polysaccharide structure
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Mathe matical model and calculation for heat transfer during condensation on surfaces of corrugated plates
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作者 陈亚平 周强泰 施明恒 《Journal of Southeast University(English Edition)》 EI CAS 2003年第4期347-351,共5页
A mathematical model was established for condensation on surfaces of verticalcorrugated plates based on the mechanism of heat transfer enhancement to thin down the liquid filmdue to surface tension effect between corr... A mathematical model was established for condensation on surfaces of verticalcorrugated plates based on the mechanism of heat transfer enhancement to thin down the liquid filmdue to surface tension effect between corrugated plate surfaces and liquid films. The relative heattransfer coefficients of condensation on corrugation plates were calculated in contrast withequivalent vertical plane ones. The heat transfer enhancement effects for the main geometricparameters such as pitch, height, corrugation angle, tilt angle, and fillet radii of corrugationswere analyzed to guide the optimization of corrugation structure for application. A two-scalecorrugation is suggested, which can compromise both the enhanced heat transfer effect and adequatecross section area for flows, and it makes the heat transfer coefficient 1 to 2 times more than thatof an equivalent plane one. 展开更多
关键词 CONDENSATION enhancement of heat transfer corrugated plates plate-shellheat exchanger
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Fatigue behavior of crane beam strengthened with CFRP 被引量:2
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作者 石启印 李爱群 惠卓 《Journal of Southeast University(English Edition)》 EI CAS 2007年第4期561-565,共5页
In order to study the fatigue behavior of the damaged reinforced concrete (RC) beams strengthened by carbon fiber reinforced polymer (CFRP) laminate, three T-shaped beams strengthened by CFRP and one contrasting b... In order to study the fatigue behavior of the damaged reinforced concrete (RC) beams strengthened by carbon fiber reinforced polymer (CFRP) laminate, three T-shaped beams strengthened by CFRP and one contrasting beam are tested under fatigue loading, with the parameters of different modes of strengthening and different fatigue load levels considered. The main results obtained from the tests are: the width of the crack decreases 50. 2% to 66%, and the development of the crack is limited; the stress of steel decreases 24. 1% to 28. 2%, and the stiffness increases 14.9% to 16. 1% after being strengthened. Based on the technical specification for strengthening concrete structures with CFRP and the conclusions from the tests, a calculating scheme of the flexure stiffness is given, which can be used for reference in engineering design. Finally, some suggestions are given for design in fatigue strengthening. 展开更多
关键词 RC crane beam structure strengthening fatigue test carbon fiber reinforced polymer (CFRP)
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STRUCTURE-FUNCTION FEATURES AND EFFECTS ON BLOOD COAGULATION OF SNAKE VENOM SERINE PROTEASES* 被引量:2
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作者 张云 李文辉 +3 位作者 高荣 吕秋敏 王婉瑜 熊郁良 《Zoological Research》 CAS CSCD 1998年第2期97-106,共10页
Snake venoms,especially those from the two subfamilies,Crotalinae and Viperinae,contained a lot of serine proteases. They were responsible for the hemorrhage,shock,or disorder of blood coagulation after envenomation. ... Snake venoms,especially those from the two subfamilies,Crotalinae and Viperinae,contained a lot of serine proteases. They were responsible for the hemorrhage,shock,or disorder of blood coagulation after envenomation. They acted,by activating,inactivating,or other converting effects,on almost all the components of hemostatic and fibrinolytic systems. Their sequences were homologous to trypsin-kallikrein serine proteases. Variation of primary sequences out of active center results in the difference of substrate specificities and the further difference of biological and pharmacological activities. Because of their common and unique properties compared to their physiological corresponding factors,snake venom proteases are proved to be an excellent model for the study of protease substrate discriminating mechanism. Furthermore,they have found an important position both in basic research and application of hemostasis and thrombosis in clinic. 展开更多
关键词 VENOMS Proteases Blood coagulation
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Cooling rate dependence of polymorph selection during rapid solidification of liquid metal zinc 被引量:4
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作者 田泽安 周丽丽 +2 位作者 莫云飞 梁永超 刘让苏 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2015年第12期4072-4079,共8页
The polymorph selection during rapid solidification of zinc melt was investigated by molecular dynamics simulation. Several methods including g(r), energy, CNS, basic cluster and visualization were used to analyze t... The polymorph selection during rapid solidification of zinc melt was investigated by molecular dynamics simulation. Several methods including g(r), energy, CNS, basic cluster and visualization were used to analyze the results. The results reveal that the cooling rate has no observable effect on the microstructure as TTc(Tc is the onset temperature of crystallization); and at the first stage of crystallization, although microstructures are different, the morphologies of nucleus are similar, which are composed of HCP and FCC layers; the polymorph selection of cooling rate finally takes place at the second stage of crystallization: at a high cooling rate, the rapid increase of FCC atoms leads to a FCC crystal mixed with less HCP structures; while at a low cooling rate, HCP atoms grow at the expense of FCC atoms, resulting in an almost perfect HCP phase. The results reveal that the cooling rate is one of the important factors for polymorph selection. 展开更多
关键词 polymorph selection crystal structure rapid solidification metal zinc molecular dynamics simulation
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Effect of configuration on magnetic field in cold crucible using for continuous melting and directional solidification 被引量:4
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作者 陈瑞润 杨劼人 +4 位作者 丁宏升 黄锋 苏彦庆 郭景杰 傅恒志 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2012年第2期404-410,共7页
To improve the power efficiency and optimize the configuration of cold crucible using for continuous melting and directional solidification (DS), based on experimental verification, 3D finite element (FE) models w... To improve the power efficiency and optimize the configuration of cold crucible using for continuous melting and directional solidification (DS), based on experimental verification, 3D finite element (FE) models with various configuration-elements were developed to investigate the magnetic field in cold crucible. Magnetic flux density (B) was measured and calculated under different configuration parameters. These parameters include the inner diameter (D2), the slit width (d), the thickness of crucible wall, the section shape of the slit and the shield ring. The results show that the magnetic flux density in z direction (Bz) both at the slit and at the midpoint of segment will increase with the decrease of D2 or with the increase of the width of the slit and the section area of wedge slit or removing the shield ring. In addition, there is a worst wall thickness that can induce the minimum Bz for a cold crucible with a certain outer diameter. 展开更多
关键词 cold crucible magnetic flux density configuration design directional solidification
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AgNi15 composite particles prepared by ultrasonic arc spray atomization method
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作者 谢建斌 温春明 +2 位作者 秦国义 许思勇 郭锦新 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2014年第11期3556-3561,共6页
Ultrasonic arc spray atomization (UASA) method was used to prepare high-melting-point, immiscible AgNi15 (mass fraction, %) composite particles. Sieving was used to determine the size distribution of the AgNi15 partic... Ultrasonic arc spray atomization (UASA) method was used to prepare high-melting-point, immiscible AgNi15 (mass fraction, %) composite particles. Sieving was used to determine the size distribution of the AgNi15 particles. The morphology, rapidly solidified structure and metastable solution expansion of the AgNi15 particles were analyzed by scanning electron microscopy (SEM), X-ray diffraction (XRD) and energy dispersive spectroscopy (EDS), respectively. The results show that the AgNi15 composite particles are spherical and well-dispersed, and the mass fractions of the particles with diameters <74μm and <55 μm are 99.5% and 98%, respectively. The rapidly solidified structure of the AgNi15 particles consists of spherical nickel-richβ(Ni)-phase particles dispersed throughout a silver-richα(Ag)-phase matrix andα(Ag)-phase nanoparticles dispersed throughout largerβ(Ni)-phase particles. The silver and nickel in the AgNi15 particles form a reciprocally extended metastable solution, and the solid solubility of nickel in the silver matrix at room temperature is in the range of 0.16%?0.36% (mole fraction). 展开更多
关键词 AgNi15 composite particle ultrasonic arc spray atomization rapidly solidified structure metastable solution extension
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Reliability analysis for anchorage of reinforced concrete beams with longitudinal cracks due to corrosion at anchorage zone
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作者 史波 赵国藩 《Journal of Southeast University(English Edition)》 EI CAS 2005年第3期336-341,共6页
An anchorage reliability analysis approach for simply supported reinforced concrete beams under corrosion attack in the anchorage zone is developed.The first-order second-moment method is employed to analyze the effec... An anchorage reliability analysis approach for simply supported reinforced concrete beams under corrosion attack in the anchorage zone is developed.The first-order second-moment method is employed to analyze the effects of various factors on the anchorage reliability.These factors include both the length and width of cover cracking due to reinforcement corrosion,the cover thickness,the anchorage length,and the stirrup ratio.The results show that the effect of corrosion-induced crack length on the reliability index for anchorage,β0,is negligible when the crack on the concrete surface is just appearing,but with the crack widening,the β0 value is reduced significantly;the considerable changes in β0 result from a variation in cover depth and anchorage length;the effect of changes in the diameter or space of stirrups on the anchorage resistance is very limited,and the variation in β0 is also very low. 展开更多
关键词 reinforcement corrosion bond behavior ANCHORAGE reinforced concrete structure corrosion-inducedcrack
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Effect of spark plasma sintering temperature on microstructure and mechanical properties of melt-spun TiAl alloys 被引量:1
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作者 柴丽华 陈玉勇 +1 位作者 张来启 林均品 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2012年第3期528-533,共6页
A TiAl alloy from pulverized rapidly solidified ribbons with the composition of Ti-46Al-2Cr-4Nb-0.3Y(mole fraction,%) was processed by spark plasma sintering(SPS).The effects of sintering temperature on the micros... A TiAl alloy from pulverized rapidly solidified ribbons with the composition of Ti-46Al-2Cr-4Nb-0.3Y(mole fraction,%) was processed by spark plasma sintering(SPS).The effects of sintering temperature on the microstructure and mechanical properties were studied.The results show that the microstructure and phase constitution vary with sintering temperature.Sintering the milled powders at 1200 ℃ produces fully dense compact.Higher sintering temperature does not improve the densification evidently.The dominant phases are γ and α2 in the bulk alloys sintered at 1200 ℃.With higher sintering temperature,the fraction of α2 phase decreases and the microstructure changes from equiaxed near γ grain to near lamellar structure,together with a slight coarsening.The bulk alloy sintered at 1260 ℃ with refined and homogeneous near lamellar structure reveals the best overall mechanical properties.The compressional fracture stress and compression ratio are 2984 MPa and 41.5%,respectively,at room temperature.The tensile fracture stress and ductility are 527.5 MPa and 5.9%,respectively,at 800 ℃. 展开更多
关键词 TiAl alloy rapid solidification spark plasma sintering MICROSTRUCTURE mechanical properties
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Measurement and analysis of defects in high-performance concrete with three-dimensional micro-computer tomography 被引量:8
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作者 郭丽萍 Andrea Carpinteri +1 位作者 孙伟 秦文超 《Journal of Southeast University(English Edition)》 EI CAS 2009年第1期83-88,共6页
In order to investigate the effects of two mineral admixtures (i. e., fly ash and ground slag)on initial defects existing in concrete microstructures, a high-resolution X-ray micro-CT( micro-focus computer tomogra... In order to investigate the effects of two mineral admixtures (i. e., fly ash and ground slag)on initial defects existing in concrete microstructures, a high-resolution X-ray micro-CT( micro-focus computer tomography)is employed to quantitatively analyze the initial defects in four series of highperformance concrete (HPC)specimens with additions of different mineral admixtures. The nigh-resolution 3D images of microstructures and filtered defects are reconstructed by micro- CT software. The size distribution and volume fractions of initial defects are analyzed based on 3D and 2D micro-CT images. The analysis results are verified by experimental results of watersuction tests. The results show that the additions of mineral admixtures in concrete as cementitious materials greatly change the geometrical properties of the microstructures and the spatial features of defects by physical-chemistry actions of these mineral admixtures. This is the major cause of the differences between the mechanical behaviors of HPC with and without mineral admixtures when the water-to-binder ratio and the size distribution of aggregates are constant. 展开更多
关键词 high-performance concrete DEFECT MICROSTRUCTURE X- ray micro-focus computer tomography mineral admixtures
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Damage of concrete attacked by sulfate and sustained loading 被引量:14
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作者 金祖权 孙伟 +1 位作者 蒋金洋 赵铁军 《Journal of Southeast University(English Edition)》 EI CAS 2008年第1期69-73,共5页
The damage processes of ordinary concrete and high strength concrete, attacked by solutions of 2. 5%, 5. 0% and 10% Na2SO4(mass fraction)are studied. And the effects of flexural loads with stress ratios of 25% and 5... The damage processes of ordinary concrete and high strength concrete, attacked by solutions of 2. 5%, 5. 0% and 10% Na2SO4(mass fraction)are studied. And the effects of flexural loads with stress ratios of 25% and 50% of the initial flexural strength on the damage process of concrete are also investigated. The results show that the damage process of concrete attacked by sulfate salt exhibits an initial damaged stage, a performance improving stage and a performance worsening stage. When the concentration of Na2SO4 in a solution increases from 2. 5% to 5.0%, the service time of the concrete decreases approximately 25%. Furthermore, it decreases to even 40% with an increase in a Na2SO4 concentration up to 10%. And the flexural load accelerates the deterioration rate of the concrete in the latter period. The stress ratio increases from 0 to 25%, the failure time of the concrete decreases 15% ; and the failure time decreases between 25% and 35% when the stress ratio increases from 25% to 50%. In addition, sulfate corrosion products of concrete are studied by SEM (scanning electron microscopy), EDS (energy disperse spectroscopy) and XRD(X-ray diffraction). 展开更多
关键词 CONCRETE SULFATE flexural load MICROSTRUCTURE
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BOND PERFORMANCE EXPERIMENT FOR FLY ASH CONCRETE AND STEEL BAR
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作者 王倩 吴瑾 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI 2012年第3期302-306,共5页
The impact of fly ash content on bond performance of steel bars and their surrounding concrete is studied by means of sticking strain gauges on steel bars. The average bond stress-slip curves, the steel strain-anchor ... The impact of fly ash content on bond performance of steel bars and their surrounding concrete is studied by means of sticking strain gauges on steel bars. The average bond stress-slip curves, the steel strain-anchor location curves, and the bond stress-anchor position curves of the pullout specimens with various fly ash contents are obtained. Results indicate that the bond performance of concrete and steel bars can be improved and the distribution of steel strain along the anchorage length tends to be more uniform by adding fly ash in concrete specimens, and both ultimate bond stress and ultimate slip deformation increase the most when 20% of specimens′ content is fly ash. 展开更多
关键词 fly ash concrete bond performance fly ash content bond stress distribution
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