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Cu-In-Cr ternary alloy specimens were prepared with a metal mould and analysed by OP, EPMA, SEM, etc. The results show that the phase composition of Cu-11In-10Cr (wt-%) ternary alloy in casting microstructure includes Cu solid solution, Cr solid solution and Cu9In4 (δ) phase. Cu solid solution has dendritic morphology while Cr solid solution is star or petal shaped and is dispersed. In solidification, the solid/liquid interfaces of Cu solid solution and Cr solid solution are nonfaceted and they form by continuous growth, Cu solid solution forms dendrites under the influence of constitutional supercooling, while Cr solid solution forms equiaxed dendrites owing to the restricted chromium content. Chromium content has an influence on the morphology of Cu solid solution dendrites and Cr solid solution. [ABSTRACT FROM AUTHOR]

The precipitation of arsenic in annealed Be delta-doped GaAs grown by low-temperature molecular-beam epitaxy has been studied using transmission electron microscopy. It was found that the planes doped with [Be] = 1.0 10[sup 14] cm[sup -2] always accumulate As precipitates, while the planes doped with [Be] = 1 × 10[sup 13] cm[sup -2] tend to deplete As precipitates. In contrast, the planes doped with [Be] = 3 and 2 × 10[sup 13] cm[sup -2] exhibit a weak accumulation property when annealed at 700 °C, but a depletion property when annealed 800 °C. The existence of twins and/or precipitates around the [Be]= 1.0 × 10[sup 14] cm[sup -2] doped planes found in the as-grown sample suggests a strain-induced mechanism to account for the As precipitates accumulation on these planes. [ABSTRACT FROM AUTHOR]

Two specimens of the rare Amarsipa fish, Amarsipus carlsbergi, were collected from Pratas Island in the northern South China Sea. They represent the first record of Taiwanese EEZ and fill the distribution gap in the northwestern Pacific Ocean between Japan (East China Sea) and Vietnam. The two specimens were identified based on their diagnostic characteristics, including no pharyngeal sacs, a pelvic fin well in front of the pectoral fin, a slender body and other morphology. Detailed data and descriptions of these two specimens, including a description of otolith morphology, are provided.

A new pineapple fish is described based on 26 type and 80 non-type specimens collected from Taiwan, Vanuatu, the Solomon Islands, and Queensland, Australia. This new species is sympatric with and similar to Monocentris japonica but can be distinguished from the latter in having only 6 or 7 scales on the third scale row below the lateral line; excisura notched and a small pseudo-excisura present on the sagittal otolith; consistently greater head depth, body depth, postorbital length, dorsal-fin-pelvic-fin length, and dorsal-fin-pectoral-fin length in proportion to standard length. A detailed description and designation of neotype are provided for M. japonica. DNA barcoding analysis supports the distinction of the new species with an estimated average COI gene divergence of 3.6 % from M. japonica.

We have studied the oxidation of microperoxidase-8 (MP-8) by H2O2 and the subsequent reaction of the intermediates with substrate by stopped-flow experiments. Oxidation of MP-8 by H2O2 gives two intermediates, I and II. The observed rate constant for the formation of I is linearly dependent on [H2O2] and exhibits a bell-shaped dependence on pH with pKa values of 8.90 and 10.60, which are attributed to the deprotonation of MP-bound H2O2 and H2O, respectively. The observed rate constant for the conversion of I to II is independent of [H2O2], but increases sharply at pH>9.0. The predominant forms of the intermediate at pH 7.0 and 10.7 are I and II, respectively. Addition of substrate to the intermediates at pH 9.0 gives rise to three distinct stages, corresponding to the three steps (in decreasing order of rate): I-->II*, II-->MP, and II*-->MP. The rates of these steps are all linearly dependent on the substrate concentration and each individual rate constant has been determined. Substrate reactivity at pH 10.7 covers over two orders of magnitude, ranging from 1.36 x 10(7) M(-1) s(-1) for 1-naphthol to 4.03 x 10(4) M(-1) s(-1) for ferrocyanide. The substrate reactivity is linearly correlated with its reduction potential, indicating that an electron transfer process is involved in the rate-limiting step.

An efficient synthesis of 3,3'-diphenyl-2,2'-bithiophene based bis(triarylamines) and their physical properties are reported.