Nagoya Institute of Technology

About: Nagoya Institute of Technology is a education organization based out in Nagoya, Japan. It is known for research contribution in the topics: Thin film & Turbulence. The organization has 10766 authors who have published 19140 publications receiving 255696 citations. The organization is also known as: Nagoya Kōgyō Daigaku & Nitech.

Factors affecting the phase and morphology of CaCO3 prepared by a bubbling method

Abstract: Precipitated calcium carbonate (PCC) was prepared by bubbling a CO 2 /N 2 mixed gas into a CaCl 2 solution. The influence of preparation conditions on the phase and morphology of PCC was discussed with the help of XRD and SEM measurements. The results showed that the initial CaCl 2 concentration, flow rate and temperature play an important role on the morphology of PCC. At low initial CaCl 2 concentration or high flow rate, spherical vaterite was preferably formed. Otherwise, the rhombic calcite was ready to form. Temperature is a determining factor on the formation of aragonite. Needle-like aragonite was precipitated at 60 °C. The results also indicated that both the bubbling time and stirring rate have a minor effect on the phase and morphology of PCC.

Environmentally Friendly One-Pot Synthesis of α-Alkylated Nitriles Using Hydrotalcite-Supported Metal Species as Multifunctional Solid Catalysts

Abstract: A ruthenium-grafted hydrotalcite (Ru/HT) and hydrotalcite-supported palladium nanoparticles (Pd(nano)/HT) are easily prepared by treating basic layered double hydroxide, hydrotalcite (HT, Mg(6)Al(2)(OH)(16)CO(3)) with aqueous RuCl(3)n H(2)O and K(2)[PdCl(4)] solutions, respectively, using surface impregnation methods. Analysis by means of X-ray diffraction, and energy-dispersive X-ray, electron paramagnetic resonance, and X-ray absorption fine structure spectroscopies proves that a monomeric Ru(IV) species is grafted onto the surface of the HT. Meanwhile, after reduction of a surface-isolated Pd(II) species, highly dispersed Pd nanoclusters with a mean diameter of about 70 A is observed on the Pd(nano)/HT surface by transmission electron microscopy analysis. These hydrotalcite-supported metal catalysts can effectively promote alpha-alkylation reactions of various nitriles with primary alcohols or carbonyl compounds through tandem reactions consisting of metal-catalyzed oxidation and reduction, and an aldol reaction promoted by the base sites of the HT. In these catalytic alpha-alkylations, homogeneous bases are unnecessary and the only by-product is water. Additionally, these catalyst systems are applicable to one-pot syntheses of glutaronitrile derivatives.

Mechanism of photosurface deposition

Abstract: To understand photosurface deposition (PSD) phenomenon, the deposition mechanism of Ag particles on Ag-rich AgAsS glasses under illumination has been investigated from a view point of electrical effects. The photo-deposited Ag particles are found to be negatively charged under illumination. PSD can effectively be suppressed by coating over the surface with semi-transparent metallic films of work function greater than 4.3 eV, which are positively charged under illumination. The Ag deposition with similar morphology as that observed in PSD can be induced by application of d.c. voltage or by irradiation of an electron beam. These observations suggest that the growth of Ag particles in PSD can be explained by a purely electrical model.

Bubble Effects on the Solution IR Drop in a Vertical Electrolyzer Under Free and Forced Convection

Abstract: Effects of electrolytic bubbles on the IR drop of caustic soda solution in a vertical cell of one meter height were studied under both free and forced convection. Three pairs of Luggin‐Haber probes were positioned near the anode and the cathode to determine the solution IR drop during electrolysis. A sectioned electrode having 10 segments was employed to obtain the current distribution from the bottom to the top of cell. The superficial resistivity of the solution containing gas bubbles agreed well with the Bruggemann equation. The solution IR drop decreased significantly when adequate conditions or cell geometry for solution circulation were provided. The anode‐to‐cathode gap was found to be the most important parameter for reduction of the solution IR drop in a vertical cell.

High Proton Conductivity in Porous P2O5−SiO2 Glasses

Abstract: High proton conducting P2O5−SiO2 glasses were prepared using the sol−gel method, the electrical conductivities of which were studied in relation to the pore structure and the adsorbed water. The pore properties of SiO2 and P2O5−SiO2 glasses were controlled by addition of formamide during the gel synthesis, the specific surface areas of which were changed from 200 to 900 m2/g-glass. These glasses absorb water molecules on exposure to a humid atmosphere. The conductivity increased with increasing logarithm of water concentration and reached a saturated value above the water vapor pressure of 0.8. The highest conductivity, 2 × 10-2 S/cm at room temperature, was achieved by 5P2O5−95SiO2 glass heated at 700 °C and absorbing the water molecules.