National Institute of Advanced Industrial Science and Technology

About: National Institute of Advanced Industrial Science and Technology is a government organization based out in Tsukuba, Ibaraki, Japan. It is known for research contribution in the topics: Catalysis & Thin film. The organization has 22114 authors who have published 65856 publications receiving 1669827 citations. The organization is also known as: Sangyō Gijutsu Sōgō Kenkyū-sho.

Control of viscosity in starch and polysaccharide solutions with ultrasound after gelatinization

Abstract: Application of power ultrasound has immense potential for a wide variety of processes in the food industry which include sterilization, emulsification, extraction, crystallization, degassing, filtration, drying, and more. Controlling the viscosity of starch (polysaccharide) solutions is one of the most promising processes to be developed. Power ultrasound can effectively decrease the viscosity of starch solutions after gelatinization. At the high starch concentrations (20–30%), starch gel can be liquidized by sonication. The viscosity of the starch solution of moderate concentration (5–10%) can be reduced about two orders of magnitude to 100 mPa·s by the ultrasonic irradiation for 30 min. The treated solution can be efficiently powdered by a spray-dryer after the sonication. The effectiveness of the ultrasonic process has been evaluated by measuring the changes in viscosity. Granule disintegration was determined using a method which measures the swelling power of starch. Change in molecular weight of the starch was monitored by gel permeation chromatography and a static light scattering method. The depolymerization process of the starch has been also monitored by NMR spectroscopy. The elucidated merits of the ultrasonic process are: 1) the process does not require any chemicals and additives; 2) the process can be simple and rapid, which means that the process is cost effective; and 3) the process will not induce large changes in the chemical structure and in particular, the properties of starches. The ultrasonic process has been confirmed to be applicable for many kinds of starches (corn, potato, tapioca, and sweet potato) and polysaccharides. Industrial relevance Starches and a variety of polysaccharides are used in a multitude of applications throughout the food industry. Ultrasonically assisted modification of their chemical and physical characters is an important process and has commercial potential. In this paper, the changes in their viscosity, molecular weight, and the NMR spectra have been measured to evaluate the effectiveness of the ultrasonic process for the depolymerization and the viscosity control of the starch and polysaccharide solutions after gelatinization.

New Member of BiS2-Based Superconductor NdO1-xFxBiS2

Abstract: We have successfully synthesized the new BiS2-based superconductor NdOBiS2 by F doping. This compound is composed of superconducting BiS2 layers and blocking NdO layers, which indicates that the BiS2 layer is analogous to the CuO2 layer in cuprates or to the Fe–As layer in Fe-based superconductors. We can obtain NdO1-xFxBiS2 with bulk superconductivity by a solid-state reaction. Therefore, NdO1-xFxBiS2 should be a suitable material for elucidating the mechanism of superconductivity in the BiS2 layer.

Single quantum dot-micelles coated with silica shell as potentially non-cytotoxic fluorescent cell tracers.

Abstract: The present study describes a stabilization of single quantum dot (QD) micelles by hydrophobic silica precursors and an extension of the silica layer to form a silica shell around the micelle. The obtained product consists of up to 92% of single nanocrystals (CdSe, CdSe/ZnS, or CdSe/ZnSe/ZnS quantum dots) in the silica micelles, coated with silica shell. The thickness of silica shell could vary, starting from 3 to 4 nm. Increasing the shell thickness increases the photoluminescent characteristics of QDs in aqueous solution. The silica-shelled single CdSe/ZnS QD micelles possess a high quantum yield in aqueous solution, a controlled small size, sharp photoluminescence spectra (fwhm ∼30 nm), an absence of aggregation, and a high transparency. The presence of a hydrophobic layer between the QD and silica shell ensures an incorporation of other hydrophobic molecules (with interesting properties) in the close proximity of nanocrystal. Thus, it is possible to combine the characteristics of hybrid material with ...

Spin-Hall insulator.

Abstract: Recent theories predict dissipationless spin current induced by an electric field in doped semiconductors. Nevertheless, the charge current is still dissipative in these systems. In this work, we theoretically predict the dissipationless spin-Hall effect, without any accompanying charge current, in some classes of band insulators, including zero-gap semiconductors such as HgTe and narrow-gap semiconductors such as PbTe. This effect is similar to the quantum-Hall effect in that all the states below the gap contribute and there occurs no dissipation. However, the spin-Hall conductance is not quantized even in two dimensions. This is the first example of a nontrivial topological structure in a band insulator without any magnetic field.