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161.
Akashi Megumi Keplinger Olga Shevchenko Natalia Anders Sten Reuter Markus A. Eckert Sven 《Metallurgical and Materials Transactions B》2020,51(1):124-139
Metallurgical and Materials Transactions B - We present an experimental study on the formation and behavior of a liquid metal bubbly flow arising from a downward gas injection through a top... 相似文献
162.
T Ishidate S Yoshihara Y Kawasaki BC Roy K Toyoshima T Akiyama 《Canadian Metallurgical Quarterly》1997,409(2):237-241
Landmarks in the development of treatment of retinal detachment include the recognition of the significance of retinal breaks that resulted in the distinction between rhegmatogenous retinal detachment (RRD) and exudative retinal detachment, the development of indirect ophthalmoscopy and scleral depression that allow better visualization of the peripheral area of the retina and better identification of retinal breaks, the recognition of the need to seal all retinal breaks, and the realization that vitreous traction is the major underlying cause of retinal tears and RRD. Scleral buckling procedures combine retinopexy to provide a scar around retinal breaks to seal them and scleral indentation to neutralize vitreous traction; they provided the first effective treatment of RRD. As surgeons gained experience with scleral buckling, they became aware that some RRDs, particularly those with fixed folds and/or a funnel configuration, often could not be repaired using this approach. It was thought that excessive vitreous traction was at fault, and the condition was called "massive vitreous retraction." 相似文献
163.
Yao Zhang Takehumi Suga Mutsurou Kawasaki Xiao-Xia Tang Nozomu Uchida Keizo Uematsu 《Journal of the American Ceramic Society》1996,79(2):435-440
The effect of poly(vinyl alcohol) adsorption on segregation was quantitatively studied by a model experiment of one–dimension drying and simulated by a mathematical model. It was clear that the adsorption of PVA on alumina particle was a slow process, and the adsorbed binder was not desorbed at higher temperature. PVA segregation can significantly be limited by fully adsorbing the binder before drying. The simulation and experiments agreed very well. The effects of drying temperature, initial concentration of the binder, and thickness of specimen on the surface segregation are discussed quantitatively. Mathematical simulation has a great potential for predicting the segregation of soluble components during drying, especially for such cases as thin films and small granules where it is difficult to determine the distribution of the component directly. 相似文献
164.
165.
A Novel Preparation Method for Foamed Silica Ceramics by Sol-Gel Reaction and Mechanical Foaming 总被引:1,自引:0,他引:1
A simple method for obtaining silica foam has been developed by combining sol-gel reaction and mechanical foaming without added organic pore formers, in order to reduce generation of CO2 and harmful gases by decomposition of the organic compounds. The silica foam was prepared by mechanically foaming the silica sol and controlling the viscosity change and gelling. The gelation time of the silica sol can be varied from 10 minutes to 3 hours by changing the pH, temperature and concentration of the surfactant added as a foam stabilizer. The dried silica gel foam was calcined at 600°C then fired at 1000°C to obtain sintered silica foam. The porosity and average pore size of the silica foam was 84% and 140 m, respectively. The bending strength and gas permeability of the sintered silica foam was 2.4 MPa and 9.4 × 10–11 m2, respectively. 相似文献
166.
Keiji Izumi Megumi Murakami Takenori Deguchi Arihiko Morita Noboru Tohge Tsutomu Minami 《Journal of the American Ceramic Society》1989,72(8):1465-1468
The stability and the coating characteristics of a variety of organozirconium compounds have been investigated to coat ZrO2 films on stainless steets for the improvement of heat resistance against oxidation. Zirconium tetraoctylate and zirconium tetrakis(acetylacetonate) were found to be more stable than zirconium alkoxides in an ambient atmosphere. The ZrO2 films from zirconium alkoxides became white and discontinuous when the thickness of the films exceeded about 200 Å (20 nm). On the other hand, transparent ZrO2 films were obtained from zirconium tetraoctylate and zirconium tetrakis(acetylacetonate). The IR spectra of the films showed that the heat treatment at 400°C for 5 min produced organic-free ZrO2 films. The heat resistance of stainless steel sheets against oxidation was improved by the ZrO2 coating, depending on the film thickness. 相似文献
167.
Structural observations and biomechanical measurements of clarinet reeds made from Arundo donax 下载免费PDF全文
Masahiro Kawasaki Tadashi Nobuchi Yuta Nakafushi Masateru Nose Masateru Shibata Peng Li Makoto Shiojiri 《Microscopy research and technique》2017,80(8):959-968
Plant anatomy was examined for two clarinet reeds made out of Arundo donax by different means of microscopy: light microscopy, low‐energy secondary electron scanning electron microscopy (SEM), backscattered electron SEM, and helium ion microscopy (HiM). The local indentation hardness HIT and Young's modulus EIT of different tissues on their cross sections were measured. A vascular bundle (Vb) (HIT = 60–100 MPa, EIT = 1,500–2,000 MPa) that includes soft tissues of phloem and xylem and a vascular bundle sheath (Bs) (HIT = 300–500 MPa, EIT = ~7,000 MPa) form a pipe of the strong string along the longitudinal direction of the cane. This Vb/Bs string is connected transversally with a net of thin cell‐walls of parenchyma cells (Pa) (HIT = 70–200 MPa, EIT = 2,000–3,000 MPa) that also range along the longitudinal direction of the cane. It was turned out that the acoustic quality of a reed is mainly ascribed to the shape and configuration of Vb and the size of Pa. A reed where Vb bundles with continuous Bs rings are homogeneously distributed with higher proportion among a softer network of small Pa cells enables musical performance. 相似文献
168.
I. Sugai M. Oyaizu Y. Takeda H. Kawakami T. Hattori K. Kawasaki 《Nuclear instruments & methods in physics research. Section A, Accelerators, spectrometers, detectors and associated equipment》2008,590(1-3):37
Carbon stripper foils with a higher nitrogen content were made by ion beam sputtering with reactive nitrogen gas. Such foils seem to be very useful as strippers for high-intensity heavy ion accelerators. To know further characteristics of the lifetime of such carbon foils, we have measured the sputtering yield of the carbon source material at a sputtering voltage of 4–15 kV and the lifetime dependence of such foils on thickness. Lifetime measurement was performed with a 3.2 MeV Ne+ ion beam. The sputtering yield on average showed 0.75 atoms/ion at over 9 kV sputtering voltage. The lifetime of the foils noticeably depends on the foil thickness, and the thickness range as practical stripper foil is to be around 15 to 33 μg/cm2. Two foils made at 13 kV showed extremely long lifetimes of 6800 and 6000 mC/cm2 at maximum and the foils made above 10 kV lived longer than about 900 mC/cm2, which correspond to about 270 and 40 times longer than commercially available best foils. We measured the thickness ratio of nitrogen to carbon in each foil made at the different sputtering voltages and at the different irradiation stages (mC/cm2) by RBS method. We also inspected the structure of a nitrided carbon foil by transmission electron microscopy. 相似文献
169.
I. Sugai M. Oyaizu Y. Takeda H. Kawakami T. Hattori K. Kawasaki 《Nuclear instruments & methods in physics research. Section A, Accelerators, spectrometers, detectors and associated equipment》2008,590(1-3):32
We control the amount of carbon buildup on slackened thin cluster carbon stripper foils (less than 3.5 μg/cm2) by heating with a high-power infrared lamp during beam bombardment. Foil lifetime measurements were performed using 2.0±0.5 μA beams of 3.2 MeV Ne+ ions and quantified as the total charge/area before breakage. Lifetimes were obtained up to 1286 mC/cm2 at maximum and 1139 mC/cm2 on the average; these values are, respectively, approximately 51 times at maximum and 46 times on average greater than the best commercially available foils, when used unheated and unslackened. 相似文献
170.
Tsuyoshi Ito Toshimasa Ohashi Hideyuki Hosokawa Tooru Kawasaki Motohiro Aizawa Yukie Ishizawa 《Journal of Nuclear Science and Technology》2016,53(6):831-841
The Pt coating (Pt-C) process has been developed to lower the recontamination by radioactive elements after chemical decontamination of piping surfaces. In this process, a layer of fine Pt nano particles is formed in an aqueous solution on the base metal of the piping following the chemical decontamination. In this study, we confirmed that the suppression effect by the Pt-C toward 60Co deposition on type 316 stainless steel using a 60Co deposition test under hydrogen water chemistry. Furthermore, we investigated the suppression mechanism of deposition of radioactive elements by a quantum molecular simulation. The deposition amounts of 60Co which were incorporated in oxides after 1000 h with and without the Pt-C process were about 90 and 10.2 Bq/cm2, respectively. The amount of 60Co deposition with Pt-C is about 10% that of non-coated specimens. The 60Co incorporation for the Pt-C specimen was suppressed by decreasing the formation of oxides. We considered this phenomenon using a quantum dynamics calculation and concluded that the Fe–O bonds in oxides were weakened by the effect of Pt and hydrogen radicals which were produced in the reaction between H2 and Pt, and then oxides were dissolved into the water. 相似文献