著者
大家 泉
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.22, no.3, pp.185-190, 2012 (Released:2012-09-05)
参考文献数
2

Helium is a rare gas found in limited quantities worldwide. Numerous problems will appear regarding production and distribution arising from the various circumstances confronting helium in recent years. This article analyzes the current status of helium for industrial use and based on this shows the difficulties faced by helium for use.
著者
小林 篤 川村 麻梨子 大原 絵里 荻野 美由紀 星野 純 山﨑 彬 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.24, no.1, pp.48-51, 2014 (Released:2014-03-20)
参考文献数
9
被引用文献数
1

This paper described the cases where a high-pressure treatment of 200 MPa was found to be effective against the two typical heat-resistant spores, B. subtilis and B. cereus when conducted as a pretreatment step before heat sterilization at 90 to 100℃. In addition, when the B. cereus was used as the indicator, it took 36 minutes (D=3 min.) to complete the heat sterilization at 100℃, whereas the holding time of only 6 minutes (D=0.5 min.) was enough to achieve sterility by using the Hi-Pit (high-pressure induced transformation) effect.
著者
藤原 義弘 河戸 勝
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.20, no.4, pp.315-320, 2010 (Released:2010-12-11)
参考文献数
27

Whale carcasses support unique biological assemblages in deep sea. The carcasses release reducing chemicals such as hydrogen sulfide and nourish chemosynthesis-based biological communities. Two “stepping-stone” hypotheses regarding whale-fall ecosystems have been proposed. One explains a dispersal pathway for hydrothermal vent/hydrocarbon seep faunae in the deep sea and another an evolutionary process of vent/seep specialists. Here we summarize the whale-fall ecosystems, especially in Japanese waters and our attempts to verify the hypotheses.
著者
清水 克哉
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.20, no.2, pp.133-139, 2010 (Released:2010-06-02)
参考文献数
35

In this article, recent advances in the fundamental and applied researches on superconductors at high pressure were reviewed. It was described how efficiently modern observation techniques and theories were combined with high pressure to get insight into the properties of solids, liquids, and gases on the molecular level and to explore new superconducting materials.
著者
飯塚 理子
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.26, no.2, pp.128-139, 2016

Newly designed opposed-type anvil assemblies were developed for acquiring high signal intensity of neutron diffraction data and ruby fluorescence spectra. Ni-binded WC anvils with a wide aperture angle, which were combined with a hybrid gasket made of TiZr and Al-alloy, achieved nearly 15 GPa at room temperature. The neutron diffraction intensity was 2.5-3.0 times greater than that using the conventional toroidal anvil assemblies. The performance test of these new anvil assemblies confirms that sufficient quality diffraction data can be obtained. Using these assemblies, high-pressure behavior of hydrogen bond in Ca(OD)2 was investigated at PLANET beamline, J-PARC.
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

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
田中 義孝
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.238-244, 2007 (Released:2007-08-30)
被引用文献数
3 3

The quality of cutting of diamond anvils from the stone crystal has a decisive influence on high-pressure generation using a diamond anvil cell (DAC). Recently, we have established a high-precision processing technology for the cutting. The development enabled to design a simple and convenient DAC without any adjustment mechanism to parallelize culet-faces of opposite anvils. The current situation in the manufacturing floor is also reported on.
著者
神田 久生 角谷 均
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.206-215, 2007 (Released:2007-08-30)
参考文献数
27

Methods to synthesize diamond under high pressure and temperature conditions are summarized, and characteristics of the synthetic diamonds are also presented. There are two ways to synthesize diamonds. One is to grow large crystals in mm size, and the other is to grow grit size up to 1 mm. Typical morphology and optical properties are demonstrated.
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
乾 雅祝 石川 大介 田村 剛三郎
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.4, pp.321-327, 2008-11-20 (Released:2009-01-09)
参考文献数
28

We have carried out x-ray diffraction, small-angle x-ray scattering and high-resolution inelastic x-ray scattering measurements for supercritical fluid Hg accompanying the metal-nonmetal (M-NM) transition using synchrotron radiation at SPring-8. In these structural studies we have found an increase in the short-range correlation length and the dynamical sound velocity much faster than the adiabatic sound velocity in the M-NM transition region. These findings strongly suggest the existence of a peculiar fluctuation intrinsic to the M-NM transition in the fluid, which may reflect a first-order M-NM transition predicted by Landau, the winner of the Nobel Prize in physics.
著者
浜根 大輔 藤田 尚行 八木 健彦
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.21, no.2, pp.109-114, 2011 (Released:2011-08-04)
参考文献数
31
被引用文献数
1

The so-called “Missing Xe” problem is a long standing unsolved problem and is related to many fields in Earth science: formation process and evolution of the Earth, origin and evolution of the atmosphere, and geochemistry. Although the long-held expectation was the retention of xenon in the iron-rich core, present experimental result clarified that it is unlikely to occur. This implies that we have to reconsider the missing xenon problem and encourage many scientists to pursuit other possibilities.
著者
松本 充弘
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.1, pp.58-65, 1997-02-20 (Released:2009-08-07)
参考文献数
25

Molecular dynamics computer simulation technique has been applied to investigate fluid phase change mechanisms near vapor-liquid interfaces. The simulation enables us to estimate the most relevant parameter, condensation coefficient αc, which is the ratio of condensation flux to vapor collision flux. We found: (i) αc is less than unity even for simple fluids, and αc of associating fluids is much less than that. (ii) There is a strong temperature dependence of αc. (iii) Under the nonequilibrium condition, αc depends also on the density (or pressure) and the temperature of the vapor. A simple evaporation model based on a transition state theory can explain this behavior to some extent. As related topics, molecular dynamics of nucleation processes is also described.
著者
真下 茂
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.4, pp.321-327, 2007-11-20 (Released:2007-12-23)
参考文献数
33
被引用文献数
1

Through the determination of Hugoniot parameters, we can get useful information about high-pressure phase transition, equations of state (EOS), etc. of solids, without pressure calibration. We have performed the Hugoniot-measurement experiments on various kinds of hard materials of chalcogenides, oxides, nitrides and borides by using a high time-resolution streak camera system (inclined-mirror method) to investigate the yielding property, phase transition and EOS. It was found that almost all brittle materials behave as an elasto-isotropic solid unlike metals (elasto-plastic solid), except TiB2. The high-pressure phase transitions were observed for ZnS, ZnSe, TiO2, ZrO2, Gd3Ga5O12, AlN and B4C. Some oxide materials showed virtually incompressible property in the high-pressure phase region. Here, the Hugoniot-compression data are reviewed, and the yield property and phase transition of these hard materials are discussed, as well as the EOS of the high-pressure phase.
著者
白樫 浩
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.26, no.4, pp.333-335, 2016 (Released:2016-12-27)
参考文献数
3

High pressure processing is an alternative technology for preservation of foods or causes detachment an adductor muscle of shellfish. This article describes the high pressure processing equipment which had been newly developed for oyster shucking and opening without heat-treatment.