This article reviews works by the author and his colleagues where a novel technique for quick change of supersaturation by dynamic pressure-control (DPC) method is used for studies of crystal growth. Since the DPC method can change supersaturation much faster than the ordinary temperature-control method, it is very suitable for quick experiments in microgravity. Here we report an in situ observation experiment of a dendritic crystal growth in microgravity by the DPC method.
Strong acceleration field can realize the sedimentation of even atoms, and is expected to create a crystal chemical nonequilibrium state in multi-component condensed matter. Such phenomena may be useful in many fields such as metallurgy, solid state chemistry, polymer physics, materials processing, nucleonic, as well as biochemistry. However, the researches of microscopic phenomena in solids under strong acceleration field have not ever been undertaken, being now an unprecedented area. In this article, we focus our attention on ultra-strong acceleration field (mega-gravity field) as a new extreme condition for materials science. The effects of strong acceleration field on atoms or crystal state, etc. in condensed matter and the possible applications to materials science are discussed on the basis of the theoretical analyses. The previous ultracentrifuge machines are reviewed, and an ultracentrifuge apparatus to generate a strong acceleration field of over 1 million (1×106) g at high temperature is described. The mega-gravity field experiment for solids is now started by using the apparatus.
In this article, an effect of ultrasound on chemical reactions is reviewed. The sonochemical reaction proceeds at a hot spot produced by cavitation of bubble, i. e., creation and collapse of a bubble in liquid. Temperature and pressure at the hot spot exceed 5000 K and 100 MPa, respectively, therefore, pyrolysis of solvent can occur. We present experimental technique and our recent results of sonochemical decomposition of organic liquids and synthesis of C60 from liquid benzene.
Phthalocyanine conductor NiPc (As6) 0. 5 is a double-chain system: a metal chain and macrocyle chain coexist within the same molecular column. This characteristic structure produces a two-band system: a wide π-band and narrow d-band, which is located near the Fermi level of the wide π-band. In this system, high pressure tunes the energy level of this 3dz2-band, and induces a metal-ligand charge transfer from the 3dz2-band to π-band, which was verified by the absorption spectra of infrared, near-infrared, and visible region. The vacant state of the 3/4-filled π-band is continuously filled up to 7 GPa. According to the increase of the pressure non-metallic phase which exists below 40 K at ambient pressure evolves to almost room temperature around 1 GPa.
In this paper, the ability of quartz crystal microbalance (QCM) was considered about in situ measurement in high pressure fluid. Solubility and adsorption of high pressure carbon dioxide (CO2) to polystyrene (PS) were measured using a QCM as a detector at pressures up to 17 MPa at 313. 2 K. The solubility and surface adsorption of CO2 increased almost linearly against activity of CO2. And it was found that the present method could be applied to higher pressure range than any other methods. The activity plot of solubility at various temperatures fell into one universal line. This may be very important because it suggests the possibility of obtaining the solubility at any temperature from only one measurement.
Whole-rice foods are well known to be beneficial for health. This is a story the development of our processed unpolished rice with excellent cookability, openly disclosing our failures in the course of these development. Our experience will hopefully be useful for any kind of rice research in the future.