37 Result(s)

Article

Production of amorphous tin oxide thin films and microstructural transformation induced by heat treatment

X-ray diffraction, scanning electron microscopy, transmission electron microscopy, and high resolution transmission electron microscopy were used to study tin oxide thin films deposited on Si(100) substrates a...

Z.W. Chen, J.K.L. Lai, C.H. Shek, H.D. Chen in Applied Physics A (2005)

Article

Nucleation and growth of SnO₂ nanocrystallites prepared by pulsed laser deposition

We report in detail the synthesis and microstructural characterization of SnO₂ nanocrystallites produced using a pulsed laser deposition (PLD) method. A detailed observation of the microstructural evolution of th...

Z.W. Chen, J.K.L. Lai, C.H. Shek, H.D. Chen in Applied Physics A (2005)

Article

An analysis of the grain growth kinetics in Mn₂O₃ nanocrystals

The isothermal grain growth of Mn₂O₃ nanocrystals, prepared by the chemical liquid-phase homogeneous precipitation route, was investigated at various temperatures between 200 and 500 °C for different annealing ti...

Z.W. Chen, C.H. Shek, J.K.L. Lai in Applied Physics A (2005)

Article

Nonmonotone Trust-Region Method for Nonlinear Programming with General Constraints and Simple Bounds

In this paper, we propose a nonmonotone trust-region algorithm for the solution of optimization problems with general nonlinear equality constraints and simple bounds. Under a constant rank assumption on the g...

D. C. Xu, J. Y. Han, Z. W. Chen in Journal of Optimization Theory and Applications (2004)

Article

Insights into fractal feature evolution from Au/Ge thin films after annealing

We report a perplexing behavior of fractal shape transition that results from a change in the annealing temperature and time or the film thickness ratio. We find that a compact-to-open fractal shape transition...

Z.W. Chen, S.Y. Zhang, S. Tan, J.G. Hou, Z.Q. Wu in Applied Physics A (2004)

Article

Dependence of electronic structure on the grain size in Mn₂O₃ nanocrystals

. The dependence of electron structure on the grain size in Mn₂O₃ nanocrystals has been investigated using X-ray photoelectron spectroscopy. It is found that the electron structure is sensitively dependent on the...

Z.W. Chen, S.Y. Zhang, S. Tan, J. Wang, S.Z. ** in Applied Physics A (2004)

Article

Morphological features of interfacial intermetallics and interfacial reaction rate in Al-11Si-2.5Cu-(0.15/0.60)Fe cast alloy/die steel couples

Soldering reactions are commonly observed during high pressure die casting of aluminium alloys, and involve the formation and growth of interfacial intermetallics between the die and the cast alloy. It is gene...

G. B. Winkelman, Z. W. Chen, D. H. St John, M. Z. Jahedi in Journal of Materials Science (2004)

Article

Experimental observation and simulation of fractal patterns of Au/Ge bilayer films

In this paper, we report on the simulation of fractal clusters and the comparison with experimental fractal patterns. We found that multiple fractal clusters can be formed in Au/Ge bilayer films for different ...

Z.W. Chen, S.Y. Zhang, S. Tan, J.G. Hou, Z.Q. Wu in Applied Physics A (2003)

Article

Microporosity formation in partially melted zone during welding of high nitrogen austenitic stainless steels

Gas tungsten arc welding experiments were conducted using austenitic stainless steel containing 0.51%N and 0.78%N. Microstructure observation and hardness measurement were made to study the loss of nitrogen. I...

O. Kamiya, Z. W. Chen, Y. Kikuchi in Journal of Materials Science (2002)

Article

A Nonmonotone Trust Region Method for Nonlinear Programming with Simple Bound Constraints

In this paper we propose a nonmonotone trust region algorithm for optimization with simple bound constraints. Under mild conditions, we prove the global convergence of the algorithm. For the monotone case it ...

Z. -W. Chen, J. -Y. Han, D. -C. Xu in Applied Mathematics & Optimization (2001)

Chapter

Structural Research on the Methylamine Dehydrogenase Redox Chain of Paracoccus Denitrificans

Methylotrophic bacteria can utilize C₁ compounds as the sole source of carbon and energy. Oxidation of methylamine in these organisms is catalyzed by methylamine dehydrogenase (MADH), an inducible, periplasmic en...

F. S. Mathews, Z.-W. Chen, R. C. E. Durley… in Biological Electron Transfer Chains: Genet… (1998)

Chapter

Structural studies of methylamine dehydrogenase

Methylamine dehydrogenase (MADH), found in methyldtrophic bacteria, is an inducible, periplasmic quinoenzyme which catalyzes the oxidation of methylamine to formaldehyde and ammonia (De Beer R et al. 1980). It...

F. S. Mathews, L. Chen, R. C. E. Durley, Z.-w. Chen… in Microbial Growth on C₁ Compounds (1996)

Article

Intermetallic phases formed during hot dip** of Low Carbon Steel in a Zn-5 Pct AI Melt at 450 °C

The formation and growth of intermetallic phases during hot dip** of low carbon steel in a Galfan bath (5 wt pct Al-Zn plus 0.05 pct mischmetal) at 450 °C have been studied by using scanning electron microsc...

Z. W. Chen, J. T. Gregory, R. M. Sharp in Metallurgical Transactions A (1992)

Chapter and Conference Paper

Evolution of Great Ape MHC Class I Genes

To investigate whether the classical HLA class I loci have been preserved in the great apes and to determine when the A/E recombination event took place, we have sequenced and expressed eight MHC c...

Z. W. Chen, A. L. Hughes, N. L. Letvin… in Molecular Evolution of the Major Histocomp… (1991)

Chapter

A Study of Fracture Behaviour of Steel in Metal Cutting

The subject of this work is the fracture behavior observed in the chip formation process of carbon steel by SEM. It is found that metal cutting is a process of deformation and fracture of materials. Single — p...

H. Z. Wu, Z. W. Chen in Fracture of Engineering Materials and Structures (1991)

Chapter and Conference Paper

Evolution of New World Primate MHC Class I Genes

We cloned, sequenced and transfected the MHC class I genes from three other species of bone-chimeric primates (the saddle-backed tamarin, S. fuscicollis; the common marmoset, Callithrix jacehus; an...

D. I. Watkins, T. L. Garber, Z. W. Chen… in Molecular Evolution of the Major Histocomp… (1991)

Article

Chinese Journal of Clinical Anatomy Abstracts vol 7, issue 4, 1989

A. L. Wang, E. H. Pu, Y. R. Li, Y. Q. Yin, S. Z. Zhong… in Surgical and Radiologic Anatomy (1989)