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Journal of China University of Geosciences 2009年第1期20卷 77-84页

作者： Ho-Shing yu emmy t y chang Institute of Oceanography National Taiwan UniversityTaipei

We examine slope profile types and variations in slope gradient and slope refief with depth for both passive and active margins in the northern most South China Sea. the passive South China margin is characterized by an exponential slope profile, mainly associated with clustered slope-confined canyons. the active taiwan margin shows a linear-like shape with great variations along the lower slope. Fewer canyons occur on the taiwan margin, and hence the influence of canyon incision on slope morphology is relatively less significant. Quantitative analyses of slope curvature, slope gradient and square root of relief variance are useful statistical parameters to explain characteristics and variability of morphology of the slope of the South China margin, but not for the Kaoping slope on the taiwan side. On the active taiwan margin, tectonic activities are dominant over sediment deposition and surface erosion, producing a slope profile quite different from those of passive margins of the Middle Atlantic, KwaZulu-Natal, South Africa where failure on slope and accompanying canyon incision are the dominant processes shaping the slope morphology.

关键词： slope morphology canyon statistical analysis continental margin South China Sea.

Microstructural Evolution of Infrared Brazed CP-ti Using ti-Cu-Ni Brazes

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Journal of Materials Science & technology 2011年第2期27卷 131-138页

作者： C.t.chang t.y.yeh R.K.Shiue C.S.chang Department of Mechanical Engineering National Hualien Industrial Vocational Senior High SchoolHualien 970TaiwanChina Department of Materials Science and Engineering National Taiwan UniversityTaipei 106TaiwanChina Engineered Materials Solutions 39 Perry AvenueMS 4-1AttleboroMA 02703-2410USA

Microstructural evolution of infrared vacuum brazed CP-ti using two ti-based braze alloys,ti-15Cu-15Ni and ti-15Cu-25Ni,has been *** infrared brazed joint consisted of eutectic ti 2 Cu/ti 2 Ni intermetallic compounds and ti-rich *** eutectic ti 2 Cu/ti 2 Ni intermetallic compounds disappeared from the joint after being annealed at 900 C for 1 *** contrast,the depletion rate of both Cu and Ni from the braze alloy into CP-ti substrate at 750 C annealing was greatly decreased as compared with that annealed at 900 *** ti 2 Cu/ti 2 Ni phases were observed even if the specimen was annealed at 750 C for 15 *** the Ni content of the ti-15Cu-25Ni braze alloy is much higher than that of the ti-15Cu-15Ni alloy,the amount of eutectic ti 2 Cu/ti 2 Ni phases in ti-15Cu-25Ni brazed joint is more than that in ti-15Ci-15Ni brazed ***,similar microstructural evolution can be obtained from the infrared brazed joint annealed at various temperatures and/or time for both filler metals.

关键词： Infrared Brazing CP-ti ti-Cu-Ni fillers Microstructure

A correlation between pulse diagnosis of human body and health monitoring of structures

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Earthquake Engineering and Engineering Vibration 2004年第1期3卷 117-125页

作者： C.C.chang Henry t.y.yang Department of Civil Engineering Hong Kong University of Science and TechnologyHong Kong Department of Mechanical and Environmental EngineeringUniversity of California Department of Mechanical and Environmental Engineering University of California

the concept of health monitoring is a key aspect of the field of medicine that has been practiced for a long time. A commonly used diagnostic and health monitoring practice is pulse diagnosis, which can be traced back approximately five thousand years in the recorded history of China. With advances in the development of modern technology, the concept of health monitoring of a variety of engineering structures in several applications has begun to attract widespread attention. Of particular interest in this study is the health monitoring of civil structures. It seem natural, and even beneficial, that these two health-monitoring methods, one as applies to the human body and the other to civil structures, should be analyzed and compared. In this paper, the basic concepts and theories of the two monitoring methods are first discussed. Similarities are then summarized and commented upon. It is hoped that this correlation analysis may help provide structural engineers with some insights into the intrinsic concept of using pulse diagnosis in human health monitoring, which may of be some benefit in the development of modern structural health monitoring methods.

关键词： human health monitoring pulse diagnosis structural health monitoring vibration-based techniques local detection techniques

tHEOREtICAL PREDICtION OF tHE KINEtICS CURVES OFPEARLItIC tRANSFORMAtION IN HyPO-PROEUtECtOID StRUCtURAL StEELS

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Acta Metallurgica Sinica(English Letters) 1998年第3期11卷 215-224页

作者： Z.G.Li H.B.chang t.y.Hsu Z.y.Xu X.y.Ruan Shanghai Jiaotong Univ Shanghai China

Supposing carbon contents of ferrite phases in pearlite precipitating from austenite in multicomponent steel at temperature t and in Fe-C ystem at t' are the same the pearlite formation temperature diference, can be calculated from the FeX phase diagrams and the equilibrium temperature Al. Using tp and Fe-C binary thermodynamic model, the driving forces for phase transformation from austenite to pearlite in multicomponent steels have been successfully calculated. through the combination of simplified Zener and Hillert's model for pearlite growth with Johnson-Mehl equation, using data from known ttt diagrams, the interfacial energy parameter and activation energy for pearlite formation can be determined and expressed as functions of chemical composition in steels by regression analysis. the calculated starting curves of pearlitic transformation in some commercial steels agree well with the experimental data.

关键词： pearlite formation temperature difference interfacial energy parameter activation enerpy for pearlite transformation,Johnson-Mehl equation

tHEOREtICAL PREDICtION OF PROEUtECtOID FERRItICtRANSFORMAtION IN HyPO-PROEUtECtOID StRUCtRAL StEELS

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Acta Metallurgica Sinica(English Letters) 1998年第3期11卷 207-214页

作者： H.B.chang Z.G.Li t.y.Hsu Z.y.Xu X.y.Ruan Shanghai technical Coll of Metallurgy Shanghai China

Proeutectoid ferrite with carbon content xo precipitating from austenite in a multicomponent steel at temperature t is supposed to be equivalent to proeutectoid ferrite with the same carbon content precipitating from austenite in Fe-C binary system at temperature t'.is described as the temperature difference of proeutectiod ferrite formation, and can be calculated from the Fe-X diagrams and the equilibrium temperature A3. By introducing tf and basing on the thermodynamic model for Fe-C binary alloy, the driving force for phase transformation from austenite to proeutectoid ferrite in multicomponent steels has been successfully calculated. through the Johnson-Mehl equation and using the data hem known ttt diagrams, the relationship between the chemical composition and the intedecial edenly packeter as well as activation energy for proeutectoid ferrite formation can be calculated. the starting curves of proeutectoid ferritic transformation calculated in this way in some hypo-proeutectoid structural steels agree well with the erperimental data.

关键词： proeutectoid ferrite formation temperature difference interfacial enerpy parameters activation energy for diffusion Johnson-Mehl equation

tHE ELECtROCHEMICAL BEHAVIOR OF OCEANIC MICROBIOLOGICAL INFLUENCED CORROSION ON CARBON StEEL

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Acta Metallurgica Sinica(English Letters) 2007年第5期20卷 334-340页

作者： X.t. chang y.S. yin G.H. Niu t. Liu S. Cheng S.B. Sun Institute of Materials Science and technology Ocean University of China Qingdao 266003 China College of Materials Science and technology Shandong University Jinan 250061 China

the corrosion behavior of carbon steel in the medium of marine microorganisms was investigated by electrochemical impedance spectra, polarization curves, and so on. Experimental results showed that the corrosion potential of carbon steel moved in a negative direction in the unpurified marine microorganism solution, and the polarization style of the cathodic process did not change. the electrochemical impedance spectra showed that the impedance value of the electrode decreased in the medium with bacteria, which indicated that the existence of microorganism could accelerate the corrosion progress of carbon steel.

关键词： carbon steel microbiological influenced corrosion polarization curve electrochemical impedance spectroscopy

StUDy ON tHE FINItE ELEMENt NUMERICAL SIMULAtION OF SHEEt MEtAL FORMING

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Acta Metallurgica Sinica(English Letters) 2004年第3期17卷 299-302页

作者： J.L.Song D.J.Hu Z.L.chang t.y.Li Z.B.Jiang School of Mechanical Engineering Shanghai Jiaotong University Shanghai 200030 China Department of Materials Engineering Taiyuan Heavy Machinery Institute Taiyuan 030024 China

Based on the Finite Element theory of Rigid Plastic,relevant problems during plas-tic simulation on sheet metal forming were technologically studied and simplified;a simplified model of the blank holder during the drawing process was established and the effects of related parameters on the forming processes were also *** the same time,a finite--element numerical simulation program SPID was *** distribution of strain and relationship of stress--stroke simulated were compared with experimented,the results are well coincided with each *** is verified that the analytical program is reliable.

关键词： sheet metal forming finite-element numerical simulation

Reduction of the Polarization-Dependent Loss of Long-Period Fiber Gratings by thermal Heating

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光学学报 2003年第S1期23卷 229-230页

作者： S. t. Oh S. y. chang W. t. Han U. C. Paek y. Chung Department of Information and Communications Kwangju Institute of Science and Technology (K-JIST) 1 Oryong-dong Buk-gu Gwangju 500-712 Korea

the polarization-dependent loss of UV-written long-period fiber gratings was significantly reduced by increasing the pulse repetition rate of the writing UV beam. the effect is closely related with the enhanced photos... 详细信息

关键词： PDL on for in of Reduction of the Polarization-Dependent Loss of Long-Period Fiber Gratings by thermal Heating by that rate with high

Modeling of the mechano-electrochemical effect at corrosion defect with varied inclinations on oil/gas pipelines

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Petroleum Science 2021年第5期18卷 1520-1529页

作者： Zhu-Wu Zhang Jin-chang Wang Jiu-Hong Zhang y.Frank Cheng College of Chemical Engineering Fuzhou UniversityFuzhou350116FujianChina Department of Mechanical Engineering University of CalgaryCalgaryT2N 1N4AlbertaCanada

A 3-dimensional finite element model was built to determine the effect of inclination angle of a corro sion defect on local mechano-electrochemical(M-E)effect in a simulated soil *** of the high effect of the defect inclination angle on the M-E effect,when the inclination angle is 0°(i.e.,the primary axis of the defect parallel to the longitudinal direction of the pipe),the greate st stress concentration level at the defect can be observed,which is associated with the lowest corrosion potential,the greatest anodic current density and the most serious accelerated localized *** the inclination angle is 90°,the stress concentration level reduces and the corrosion potential becomes less negative,accompanying with the decreased anodic/cathodic current ***,when the ratio(r_(ca))of the primary axial length of the defect to its secondary axial length is 1,the defect inclination does not affect the stress and the electrochemical corrosion rate at the *** the increase of r_(ca),the effect of the defect inclination angle is more apparent.

关键词： Pipelines Corrosion defect assessment Mechano-electrochemical effect Finite element model

Prevention of metabolic decompensation in an infant with mutase deficient methylmalonic aciduria undergoing cardiopulmonary bypass

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World Journal of Pediatrics 2014年第1期10卷 83-85页

作者： Raymond y Wang Richard C chang Mary E Sowa Anthony C chang Jose E Abdenur Division of Metabolic Disorders CHOC Children's FoundationDepartment of PediatricsUniversity of California Irvine School of MedicineOrangeCAUSA Department of Clinical Nutrition and Lactation CHOC Children'sOrangeCAUSA Division of Cardiology Pediatric Subspecialty FacultyHeart InstituteCHOC Children'sOrangeCAUSA

Background:Effects of circulatory arrest upon an inborn error of metabolism patient are ***:A retrospective chart review was performed of outcome and biochemical parameters obtained during palliative cardiac surgery for a mutase-deficient methylmalonic aciduria patient with Ebstein’s cardiac anomaly was ***:the levels of ammonia,methylmalonic acid,free carnitine,and propionylcarnitine of the patient were *** patient survived surgery following institution of four metabolic treatment principles:1)restriction of toxic substrate;2)promotion of anabolism via administration of carbohydrate and lipid calories;3)administration of detoxifying levocarnitine and sodium benzoate;and 4)cobalamin enzymatic co-factor *** patient died from post-operative dysrhythmia and was posthumously determined to have compound heterozygosity for mutations predicting severe,cobalamin non-responsive disease:c.322C>t/c.1233del3(p.R108C/p.ΔI412).Conclusion:Metabolic decompensation is preventable during cardiopulmonary bypass and cardioplegia using four principles of metabolic treatment.

关键词： bypass management methylmalonic aciduria