2 0 0 0 OA 爆発圧着

著者
伊妻 猛志
出版者
The Japan Society of High Pressure Science and Technology
雑誌
高圧力の科学と技術 (ISSN:0917639X)
巻号頁・発行日
vol.4, no.2, pp.107-111, 1995-05-20 (Released:2009-08-07)
参考文献数
21

Explosion bonding process introduced commercially in 1960 has developed steadily and expanded its applications. This unique joining process makes use of controlled explosive energy and enables us to bond various kinds of dissimilar metal combinations metallurgically. This paper reviews the development of the process and describes bonding conditions, advantages and limitations of the process, and its applications.
著者
松岡 岳洋 清水 克哉 平尾 直久 大石 泰生 佐々木 重雄
出版者
日本高圧力学会
雑誌
高圧力の科学と技術 (ISSN:0917639X)
巻号頁・発行日
vol.28, no.4, pp.268-280, 2018 (Released:2018-12-28)
参考文献数
104
被引用文献数
1

In this article, recent advances in the experimental searching are reviewed. To date, there have been several tens of theoretical papers that predict the superconductivity of hydrides. On the other hand, there have been a few publications about experimental observations of the superconductivity despite the huge efforts in exploration. In this review, we introduce the ideas on how to approach to high critical temperature by hydrides, and the current achievements by experiments are summarized.
著者
笹川 秋彦 星野 純 小林 篤 西海 理之 鈴木 敦士 藤井 智幸 小西 徹也 山崎 彬 山田 明文
出版者
日本高圧力学会
雑誌
高圧力の科学と技術 (ISSN:0917639X)
巻号頁・発行日
vol.16, no.2, pp.167-178, 2006 (Released:2006-06-15)
参考文献数
35
被引用文献数
5 6

The commercial-scale feasibility of high-pressure treatment to fermented foods was investigated, with attention given to the fact that the pressure resistance varies with the kind of microorganism. Kimchi was chosen because lactic acid bacteria had been found to be separated from yeast by pressure application of 300 MPa (20°C), and subjected to pressure treatment to investigate the microbiological, physicochemical and sensory changes with the progress of fermentation. Pressure application of 300 MPa (20°C) to Kimchi for 5 minutes slightly decreased the number of lactic acid bacteria, while completely inactivated the yeast to prevent expansion of the Kimchi-containing package during the storage. The pressure treatment also reduced the generation of lactic acid, the drop in pH value and the decrease of glucose and fructose contents. Although the pressure-treated Kimchi showed increased color difference and translucence, the breaking stress was not changed. The sensory tests demonstrated the advantages of pressure-treated Kimchi, to confirm the improvement of shelf life of Kimchi.
著者
竹村 謙一
出版者
The Japan Society of High Pressure Science and Technology
雑誌
高圧力の科学と技術 (ISSN:0917639X)
巻号頁・発行日
vol.5, no.3, pp.150-155, 1996-08-20 (Released:2009-08-07)
参考文献数
41

Experimental aspects of pressure-induced metallization and structural change of rare gas solids are reviewed. The metallization process of xenon, which has been extensively investigated through optical measurements, is described in more detail as an example.
著者
阿部 文快
出版者
日本高圧力学会
雑誌
高圧力の科学と技術 (ISSN:0917639X)
巻号頁・発行日
vol.18, no.2, pp.119-127, 2008-05-20 (Released:2008-06-03)
参考文献数
51
被引用文献数
3 2

There have been innovative high-pressure studies on biological processes applying modern techniques of genetics and molecular biology in model microorganisms such as bacterium Escherichia coli and yeast Saccharomyces cerevisiae. Recent advanced investigations in this field have been systematically done in the genome-wide level to identify genes and proteins required for microbial growth and survival under high hydrostatic pressure. This article is an overview of studies on the effect of high pressure on microbial physiology and the challenges in piezophysiology, which has been proposed to discover whether the responses of living cells to high pressure are relevant to their growth and viability.
著者
長柄 一誠
出版者
日本高圧力学会
雑誌
高圧力の科学と技術 (ISSN:0917639X)
巻号頁・発行日
vol.13, no.3, pp.204-211, 2003 (Released:2003-11-05)
参考文献数
40

Compressed solid hydrogens are introduced with the basic property of the hydrogen molecule. Starting from a brief introduction of old calculations, first-principles calculations of compressed hydrogens and their results are reviewed with some of our results of calculations based on the local density approximation (LDA). The probable structures over 150 GPa and the effects of the zero-point motion of the nuclei on those structures are discussed. The structures are also examined from the view point of electronic band structure. The problems remaining for the future studies of compressed hydrogens are summarized.
著者
村上 元彦
出版者
日本高圧力学会
雑誌
高圧力の科学と技術 (ISSN:0917639X)
巻号頁・発行日
vol.18, no.1, pp.21-30, 2008-02-20 (Released:2008-03-18)
参考文献数
36
被引用文献数
1 1

Brillouin scattering measurements of the aggregate shear wave velocities in MgSiO3 perovskite and post-perovskite phase were conducted at high-pressure conditions relevant to the Earth’s lowermost mantle. Infrared laser annealing of samples in a diamond anvil cell enabled to obtain high quality Brillouin spectra and to extend the upper limit of pressure of Brillouin measurements. The large pressure range over which acoustic measurements of MgSiO3 perovskite and post-perovskite phase were performed has thereby allowed us to put tighter constraints on compositional models of the Earth’s lower mantle and enigmatic seismic observations in the lowermost mantle.
著者
青木 勝敏 町田 晃彦 大村 彩子 綿貫 徹
出版者
日本高圧力学会
雑誌
高圧力の科学と技術 (ISSN:0917639X)
巻号頁・発行日
vol.18, no.3, pp.273-278, 2008-08-20 (Released:2008-08-28)
参考文献数
19
被引用文献数
4 3

The highly compressed state of metal hydride has been investigated to explore structural and electronic transitions characteristic to hydride. The hydrogen atoms play the lead in the transitions, showing displacement in or transfer between the interstitial sites of a metal lattice. One example is the band gap closing observed for a long period lattice of yttrium tri-hydride, YH3, appearing at pressures above 12 GPa. Another example is photochromic event observed again for yttrium hydride, YHx. The former is likely accompanied by the in-site displacement of hydrogen atoms and the latter by the site-to-site transfer.
著者
笹川 秋彦
出版者
日本高圧力学会
雑誌
高圧力の科学と技術 (ISSN:0917639X)
巻号頁・発行日
vol.17, no.3, pp.230-237, 2007 (Released:2007-08-30)
参考文献数
16
被引用文献数
1

Until recently, the factor that has played a predominant role in food processing was not “ pressure” but “ heat” , although both factors are independently responsible for transforming the state of a substance. Food processing can be achieved without any cleavage of covalent bond contained in the ingredients of food. Moreover, high-pressure treatments are considered to be very promising for food processing of the future. This is because decomposition of nutrients and production of stench can be minimized more effectively and energy consumption can be reduced more efficiently when compared with heat treatment. Further, when a food product in a container is subjected to high-pressure treatment, uniform processing throughout the food can be guaranteed.
著者
西海 理之
出版者
日本高圧力学会
雑誌
高圧力の科学と技術 (ISSN:0917639X)
巻号頁・発行日
vol.27, no.1, pp.49-59, 2017 (Released:2017-04-12)
参考文献数
31

High pressure can accelerate post-mortem aging of meat, which results in improving meat tenderness. High hydrostatic pressure modifies conformation of intramuscular protein molecules, disorganizes the supermolecular structure, and then induces the structural weakening of myofibrils and intramuscular connective tissue. Although the effect of high-pressure processing on meat tenderizations is limited after cooking of meat, combining high pressure with sodium hydrogen carbonate treatments can improve texture and palatability of cooked meat and meat products. Science and technology of the high pressure processing for meat texture will be reviewed.
著者
郷農 靖之
出版者
日本高圧力学会
雑誌
高圧力の科学と技術 (ISSN:0917639X)
巻号頁・発行日
vol.11, no.4, pp.311-314, 2001 (Released:2003-02-28)
参考文献数
13

In the early days of nuclear science, many researchers tried to see if a nuclear decay constant could be changed by putting radioactive nuclei in various extreme environments, such as high and low temperatures, high pressure and high electromagnetic fields. They could not find any measurable change. Since then it was believed that a nuclear decay constant was independent of extranuclear conditions. In 1947, it was pointed out that there might be observable changes in decay constants when decay modes were dominated by an electron capture or an internal conversion process. Thereafter, many experimental studies were carried out, and their changes were observed. We studied the change of the decay constant of 99mTc by applying high-pressure. The present status of our study is described in this report.
著者
吉井 範行 三浦 伸一 岡崎 進
出版者
日本高圧力学会
雑誌
高圧力の科学と技術 (ISSN:0917639X)
巻号頁・発行日
vol.10, no.4, pp.275-282, 2000-11-20 (Released:2009-08-07)
参考文献数
64

In the recent decade, many computational studies as well as physicochemical experiments such as neutron diffraction and NMR spectroscopic measurements have actively been done in order to clarify the structure and dynamics of supercritical water and its solutions. In particular, studies on hydrogen bonding in supercritical water have been attracting much interest from physical chemists. Long-ranged structure and the relevant collective motion have also been investigated in detail. For supercritical solutions, thermodynamic properties such as solubility and the microscopic structure of ion hydration have been studied. Here, recent progress in computational studies on the structure and dynamics of the fluids is reviewed.
著者
重森 啓介
出版者
日本高圧力学会
雑誌
高圧力の科学と技術 (ISSN:0917639X)
巻号頁・発行日
vol.16, no.3, pp.243-250, 2006 (Released:2006-10-16)
参考文献数
12

We have been developing an experiment on laser-induced double-shock compression of diamond foils to a metallic phase by means of impedance-mismatching technique. We measured the reflectivity from the rear side of the diamond foil with a velocity interferometer system for any reflector. The measured reflectivity of the diamond clearly increased with the double compression. Independently measured from an optical pyrometer indicates that the compressed temperature of the diamond was approximately 7300 K, which is much lower than that of the single shock. The experimental results strongly suggest the phase transition from diamond to metallic carbon.
著者
廣瀬 敬 河村 雄行
出版者
日本高圧力学会
雑誌
高圧力の科学と技術 (ISSN:0917639X)
巻号頁・発行日
vol.14, no.3, pp.265-274, 2004 (Released:2004-12-10)
参考文献数
46
被引用文献数
1 2

MgSiO3 perovskite is believed to be a dominant mineral at least in the upper part of the Earth's lower mantle, but its stability and possible phase transition in deeper levels were not known. Recently we discovered the phase transition from MgSiO3 perovskite to a new high-pressure form (space group: Cmcm) above 125 GPa and 2500 K on the basis of in-situ x-ray diffraction measurements [1]. This phase transition is most likely responsible for the origin of the D” seismic discontinuity observed around 2700 km depth, and the MgSiO3 post-perovskite phase is a main constituent mineral in the D” region. Here we introduce the details of high-pressure experiment and crystal structure determination, and discuss the seismic anomalies in the lowermost mantle.
著者
黒木 和彦
出版者
日本高圧力学会
雑誌
高圧力の科学と技術 (ISSN:0917639X)
巻号頁・発行日
vol.19, no.2, pp.138-147, 2009 (Released:2009-06-03)
参考文献数
67

In this article, theoretical aspects of the newly discovered iron pnictide superconductors are reviewed. First we present the effective model, which turns out to contain all five 3d orbitals. Then we show how the nesting of the disconnected sheets of the Fermi surface can result in multiple modes of spin fluctuations. When one of the spin fluctuation modes dominate, the superconductivity has an s-wave symmetry where the gap changes sign between different sheets of the Fermi surface. On the other hand, when the spin fluctuation modes compete with each other, d-wave pairing becomes competitive or even dominates over s-wave pairing. We explain how the lattice structure may affect the Fermi surface and thus the Tc as well as the competition between different pairing symmetries.
著者
西山 宣正 若井 史博
出版者
日本高圧力学会
雑誌
高圧力の科学と技術 (ISSN:0917639X)
巻号頁・発行日
vol.28, no.3, pp.170-176, 2018 (Released:2018-10-04)
参考文献数
17

Nanopolycrystalline stishovite was fabricated under high pressure and temperature using Kawai-type apparatus. This material is the hardest oxide as well as one of the toughest ceramics with fracture toughness of about 12 MPa m1/2. We performed X-ray absorption spectroscopy using synchrotron radiation, bending tests using micro-cantilever specimens fabricated by focused ion beam technique, and first-principles calculations for this material. Using the obtained results, we demonstrated that this material is toughened by transformation toughening mechanism by fracture-induced amorphization of stishovite. This toughening mechanism can be a platform to produce new structural materials.
著者
阿部 和多加
出版者
日本高圧力学会
雑誌
高圧力の科学と技術 (ISSN:0917639X)
巻号頁・発行日
vol.28, no.4, pp.281-290, 2018 (Released:2018-12-28)
参考文献数
56

The idea of looking for metallic states in hydrides rather than in pure hydrogen has remarkably increased the options for attaining the high-temperature superconductivity predicted by Ashcroft in 1968. This article presents a few viewpoints which might serve as a practical guide to searching new metallic hydrides which possess high superconducting transition temperatures. According to the Goldhammer-Herzfeld criterion, it is important to pay attention to unstable compounds at one atmospheric pressure because they can be good metals at high pressures. It is also helpful to make use of possible structural similarities of hydrides between the diagonally adjacent elements in the periodic table in order to control insulator-to-metal transition. The effects of anharmonic proton zero-point energy on stable structures are also discussed by applying the self-consistent harmonic approximation to solid hydrogen.
著者
直木 基祐
出版者
The Japan Society of High Pressure Science and Technology
雑誌
高圧力の科学と技術 (ISSN:0917639X)
巻号頁・発行日
vol.9, no.2, pp.109-116, 1999-05-20 (Released:2009-08-07)
参考文献数
18
被引用文献数
6 5

Glass transformations, glass transition temperatures, various glassy states under elevated pressures, and polyamorphism are reviewed. There are two types of polyamorphism in the glassy states: the first is that produced from the history of glass-forming conditions, and the second is that produced from changes in the structure of liquids. A critical point of structural polyamorphism is deduced from the recent experiments on the first-order like glass-glass transition of tetrahedral glasses. The critical point locates on the equilibrium liquid surface in the P-V-T space under an elevated pressure below the glass transition temperature, but above the Kauzmann temperature. The low-temperature limit of the liquid under the critical pressure is the critical point; and the liquid, except the critical pressure, vitrifies gradually without any transition. The equations of the glassy states are briefly discussed.
著者
三島 修
出版者
日本高圧力学会
雑誌
高圧力の科学と技術 (ISSN:0917639X)
巻号頁・発行日
vol.13, no.2, pp.165-172, 2003 (Released:2003-09-24)
参考文献数
110
被引用文献数
4 3

Recent progress in the research in low-temperature liquid water and amorphous ices is reviewed. Polyamorphism in water is described as the key to understanding the puzzling properties of cold water. Polyamorphism is applied to other liquids under pressure and plays an important role in the study of liquids in general.
著者
加藤 隆二
出版者
The Japan Society of High Pressure Science and Technology
雑誌
高圧力の科学と技術 (ISSN:0917639X)
巻号頁・発行日
vol.6, no.3, pp.159-166, 1997-08-20 (Released:2009-08-07)
参考文献数
31

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.