Effect of nitriding on grain oriented silicon steel bearing aluminum (the second study)

All kinds of high-permeability GO are manufactured using AlN as the main inhibitor. From a purely metallurgical viewpoint, three types of inhibitor preparation for high-permeability GO have been shown. They include a complete solution without nitriding, a complete precipitation with nitriding and a partial precipitation with nitriding. In this study, another possibility, i.e., a complete solution method with nitriding, was investigated to avoid the extra high-temperature slab reheating and to examine the effect of nitriding on GO bearing Al. This method can also provide the sharp Goss texture, and nitriding is shown to be very useful for changing the inhibitor intensity, depending on the primary grain size.     

The mechanism of photocatalytic hydrogen production from gaseous methanol and water: IR spectroscopic approach

IR spectroscopic and volumetric study under reaction conditions of the mechanism of photocatalytic hydrogen production from gaseous methanol and water revealed that CO₂ and H₂ were produced by reaction between adsorbed CH₃O(ad) and H₂O. Another reaction path for H₂ production, CH₃ OH(ad) → H₂ + HCHO, was suggested which is dominant in the absence of water.     

Optical rotation inversion of porphyrin-DNA complexes

A porphyrin-DNA complex in which helical porphyrin assemblies were stacked as π-stacked aggregates on a DNA scaffold was found. The complex indicates the inversions of optical rotation by only the control of ionic equilibrium without any structural changes of DNA scaffold.     

Synthesis of pyrimidino[4,5-b][1,5]benzodiazepin-2-ones and pyrimidino[1,6-a]benzimidazol-1-ones from 4-ethoxycarbonylamino-1H-1,5-benzodiazpine-3-carbonitrile via 4-(2-aminoanilino)pyrimidin-2(1H)-one-5-carbonitriles

Reactions of 4-ethoxycarbonylamino-1H-1,5-benzodiazepine-3-carbonitrile (2) with aliphatic primary amines gave 1-substituted 4-(2-aminoanilino)pyrimidin-2(1H)-one-5-carbonitriles 3. Analogous reactions of 2 with aromatic primary amines afforded 2-(2′-anilino-1′-cyanovinyl)benzimidazoles 5 and 6. Upon treatment with triethylamine, 3 underwent intramolecular cyclization to give 3-substituted 5-aminopyrimidino[4,5-b]-[1,5]benzodiazepin-2(3H,11H)-ones 8 . Heating of 3 with p-toluenesulfonic acid in ethanol gave 2-substituted pyrimidino[1,6-a]benzimidazol-1(2H)one-4-carbonitriles 9 . Reactions of 2 with hydrazines were also described. Mechanistic pathways are proposed to account for the products.     

Polymerization-induced self-assembly of amino-acid-based nano-objects by reversible addition–fragmentation chain-transfer dispersion polymerization

A series of amino-acid-based amphiphilic diblock copolymer nano-objects having different morphologies were developed by reversible addition–fragmentation chain-transfer (RAFT) dispersion polymerization of styrene (St) in methanol. This was mediated by six different hydrophilic poly(N-acryloyl amino acid) macro-chain transfer agents (CTAs), including three carboxylic-acid-containing ones, poly(N-acryloyl-l -proline) (PAProOH), poly(N-acryloyl-4-trans-hydroxy-l -proline) (PAHypOH), and poly(N-acryloyl-l -threonine) (PAThrOH) prepared by RAFT polymerization, and their methyl ester forms, PAProOMe, PAHypOMe, and PAThrOMe. The effects of polymerization conditions on RAFT dispersion polymerization of St using a dithiocarbamate-terminated PAProOH was investigated. A systematic study of the effects of monomer conversion and concentration afforded the formation of various morphologies (i.e., spheres, worms, and vesicles). The effects of hydrogen-bonding and ionic interactions of the macro-CTAs on the assembled structures of the nano-objects were evaluated using six different macro-CTAs. Transforming the products from methanol to water via dialysis produced amino-acid-based block copolymer nano-objects, exhibiting pH-responsive morphological change, in aqueous solution.     

Enhanced photon generation in a Nb/n-InGaAs/p-InP superconductor/semiconductor-diode light emitting device

We experimentally demonstrate Cooper pairs' drastic enhancement of the band-to-band radiative recombination rate in a semiconductor. Electron Cooper pairs injected from a superconducting electrode into an active layer by the proximity effect recombine with holes injected from a p-type electrode. The recombination of a Cooper pair with p-type carriers dramatically increases the photon generation probability of a light-emitting diode in the optical-fiber communication band. The measured radiative decay time rapidly decreases with decreasing temperature below the superconducting transition temperature of the niobium electrodes. Our results indicate the possibility to open up new interdisciplinary fields between superconductivity and optoelectronics.     

Triggered single-photon emission and cross-correlation properties in InAlAs quantum dot

Triggered single-photon generation from InAlAs quantum dot (QD) was demonstrated for the first time. Emitted photon energy coincides with high detection efficiency range of Si single-photon detectors, which is highly suitable for free-space communication. Single-QD spectroscopy and crossed photon correlation measurements unambiguously revealed that several emitting lines observed in a single mesa structure originated from the identical QD, and two temporary competing decay processes associated with neutral states and charged states were identified. Presence of the competing process is also inferred from an analysis of steady-state photoluminescence intensities. Formation process of charged exciton in QD is also discussed.     

La0.7Ce0.3MnO3 epitaxial films fabricated by a pulsed laser deposition method

La_0.7Ce_0.3MnO₃ epitaxial films were successfully fabricated via a pulsed laser deposition method by controlling the experimental conditions. A series of experiments with varying the oxygen pressure and the substrate temperature demonstrated that the use of appropriate conditions is crucial for fabricating the epitaxial thin films. The existence of such suitable conditions was thermodynamically interpreted in terms of the stability of Mn²⁺ ion. Both XRD and EPMA measurements indicated that La_0.7Ce_0.3MnO₃ thin films fabricated herein form single phases, although it was difficult to present the direct experimental evidence to prove that Ce ion can really exist within the perovskite structure. The resultant films with oxygen annealing showed a metal-insulator transition and ferromagnetic property with Curie temperature of 275 K.