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121.
H.F.-W. SadrozinskiC. Betancourt A. BieleckiZ. Butko V. FadeyevC. Parker N. PtakJ. Wright Y. UnnoS. Terada Y. IkegamiT. Kohriki S. MitsuiK. Hara N. HamasakiY. Takahashi A. ChilingarovH. Fox 《Nuclear instruments & methods in physics research. Section A, Accelerators, spectrometers, detectors and associated equipment》2011,658(1):46-50
We have tested the effectiveness of punch-through protection (PTP) structures on n-on-p AC-coupled Silicon strip detectors using pulses from an 1064 nm IR laser, which simulate beam accidents. The voltages on the strips are measured as a function of the bias voltage and compared with the results of DC I-V measurements, which are commonly used to characterize the PTP structures. We find that the PTP structures are only effective at very large currents (several mA), and clamp the strips to much larger voltages than assumed from the DC measurements. We also find that the finite resistance of the strip implant compromises the effectiveness of the PTP structures. 相似文献
122.
Takuya Takahashi Motoya Suzuki Ryuji Nomura Yuichi Okuda Koji Kamiya Takenori Numazawa Peter Shirron 《Microgravity science and technology》2011,23(4):365-372
Superfluid 4He was produced on a small jet plane for the first time using a small GM-refrigerator to condense the liquid and a scroll pump to get the superfluid by evaporation. The surface wave on superfluid under 0.5g E, 0.1g E and 0.05g E, together with 2g E and 1g E, was successfully examined by an optical method utilizing parabolic flight. Here, g E is the gravitational constant on the ground. Assuming that only the fundamental mode was excited as determined by the sample cell width, the resonance peak in the frequency domain was well reproduced by the gravity wave with corresponding gravity constant. 相似文献
123.
Low‐Energy Electron Beam Induced Charging and Secondary Electron Emission Properties of FEP Film Used on Satellite Surfaces 下载免费PDF全文
Many kinds of insulating materials are used outside a spacecraft. They include FEP films, polyimide films, and so on, and are used as thermal control materials. These materials are exposed to a charged‐particle environment around the spacecraft. Thus then become charged due to charged particles, especially electrons. It has been pointed out that charging of these materials is likely to cause discharges on the surfaces. From this viewpoint, we investigated the charging potential characteristics of 127‐μm‐thick FEP film, a typical thermal control material, by exposing it to electron irradiation at various energies below 20 keV. In the dependence of the charging potential on the electron energy, we found that the electron energy at which no charge‐up occurs is about 2.7 keV. This appears to be the energy at the which secondary electron emission yield becomes unity. This indicates that electron irradiation of FEP film with energies lower than 2.7 keV induces positive charging. From the charge decay characteristics after electron irradiation, the volume resistivity of the film was also obtained as a function of the electric fields in the bulk of the FEP film. 相似文献
124.
Sae Saigo Tabito Kino Kotaro Uchida Takuya Sugawara Lin Chen Michiko Sugiyama Kengo Azushima Hiromichi Wakui Kouichi Tamura Tomoaki Ishigami 《International journal of molecular sciences》2022,23(1)
The prorenin/renin receptor ((P)RR) is a multifunctional protein that is widely distributed in various organs. Despite intensive research for more than 20 years, this receptor has not been fully characterized. In this study, we generated mice overexpressing the tubular epithelial (P)RR gene ((P)RR-TG mice) to test the previously reported functional role of (P)RR by Ramkumar et al. in 2015 using tubular specific (P)RR KO mice. (P)RR-TG mice were maintained and analyzed in individual metabolic cages and were administered angiotensin II blocker (ARB), direct renin inhibitor (DRI), and bafilomycin, that is, vacuolar ATPase (V-ATPase) antagonist. (P)RR-TG mice were hypertensive and had alkalized urine with lower osmolality and Na+ excretion. ARB and DRI, but not bafilomycin, concurrently decreased blood pressure. Bafilomycin acidized urine of (P)RR-TG mice, or equivalently this phenomenon restored the effect of overexpressed transgene, suggesting that (P)RR functioned as a V-ATPase in renal tubules. Afterall, (P)RR-TG mice were mated with alternative renin transgenic mice (ARen2-TG), which we identified as intracellular renin previously, to generate double transgenic mice (DT-TG). Lethal renal tubular damage was observed in DT-TG mice, suggesting that intracellular renin may be a ligand for (P)RR in tubules. In summary, (P)RR did not substantially affect the tissue renin-angiotensin system (RAS) in our model of tubular specific (P)RR gene over-expression, but alternative intracellular renin may be involved in (P)RR signaling in addition to conventional V-ATPase function. Further investigations are warranted. 相似文献
125.
Shoji Eita Takahashi Ryuji Isogai Shosei Ito Naoto Kubo Masaki Tsukada Takao Fukuyama Hiroyuki 《Metallurgical and Materials Transactions B》2019,50(5):2454-2458
Metallurgical and Materials Transactions B - Normal spectral emissivity of molten Cu-Fe alloy with different compositions was measured at the wavelength of 807 nm using an electromagnetic... 相似文献
126.
Plasma osmolality estimated from plasma concentrations of Na+, Cl-, K+, glucose, and urea was compared with measured osmolality in preweaned Holstein calves. When calves (n = 5) were fed only milk replacer after fasting for 24 h, measured osmolality fluctuated almost in parallel with estimated osmolality during the 8-h period after feeding, although estimated values were about 90% of measured values. When calves (n = 5) were fed only calf starter after fasting for more than 16 h, measured osmolality did not parallel the estimated osmolality during the 8-h period after feeding. Some factors depressed measured osmolality in the first 2 h. 相似文献
127.
Crack-Healing Behavior of Si3 N4 /SiC Ceramics under Cyclic Stress and Resultant Fatigue Strength at the Healing Temperature 总被引:1,自引:0,他引:1
Kotoji Ando Koji Takahashi Shin Nakayama Shinji Saito 《Journal of the American Ceramic Society》2002,85(9):2268-2272
Si3 N4 /SiC composite ceramics were sintered and subjected to three-point bending. A semi-elliptical surface crack of 100 μm surface length was made on each specimen. The crack-healing behavior under cyclic stress of 5 Hz, and resultant cyclic fatigue strengths at healing temperatures of 1100° and 1200°C, were systematically investigated. The main conclusions are as follows: (1) Si3 N4 /SiC composite ceramics have an excellent ability to heal a crack at 1100° and 1200°C. (2) This sample could heal a crack even under cyclic stress at a frequency of 5 Hz. (3) The crack-healed sample exhibited quite high cyclic fatigue strength at each crack-healing temperature, 1100° and 1200°C. 相似文献
128.
Kyoichi Osada Koretaro Takahashi Mutsuo Hatano 《Journal of the American Oil Chemists' Society》1990,67(12):921-922
The degree of glyceride syntheses by lipase TOYO (Chromobacterium viscosum) and lipase OF (Candida cylindracea) using individual free fatty acids C18∶1, C18∶2, C18∶3, C18∶4, C20∶4, C20∶5 and C22∶6 were compared. Lipase TOYO incorporated each of the fatty acids into glycerol at levels of greater than 89%. Lipase OF incorporated
most of the fatty acids at levels above 70% (docosahexaenoic acid incorporation was 63%). It was concluded that these two
lipases are feasible for producing glycerides from unsaturated fatty acids. 相似文献
129.
R.W. Callis J.L. Doane H.J. Grunloh K. Kajiwara A. Kasugai C.P. Moeller Y. Oda R.A. Olstad K. Sakamoto K. Takahashi 《Fusion Engineering and Design》2009,84(2-6):526-529
Initial testing on the Japan Atomic Energy Agency Gyrotron Test Stand of ITER-relevant TL components, has shown reasonable efficiencies, but identified that trapped modes between closely located miter bends, as well as mode conversion at miter bends can lead to excessive heating of the connecting waveguides. General Atomics has designed, built, and will test components to address this issue as well as ITER relevant components that have not been tested at the levels of 1 MW, 170 GHz, for extended pulse lengths. Some of the components that will be tested are ultra low loss miter bends, dc breaks, polarizers, power monitors, bellows, waveguide switches, waveguide cooling clamps, etc. Details of the components and test results will be presented. 相似文献
130.
Hiromichi Gima Jun Adachi Masahito Katayama Hiroaki Muta Masayoshi Uno Shinsuke Yamanaka 《Journal of Nuclear Materials》2009,389(1):155-159
We prepared polycrystalline pellets of (U,Y)O2, containing YO1.5 up to 11 mol.%. We performed indentation tests on the pellets, and evaluated the Young’s modulus and hardness. We measured the heat capacity and the thermal diffusivity, and evaluated the thermal conductivity. We succeeded in evaluating the effect of Y content on the thermophysical properties of (U,Y)O2. We revealed that the Young’s modulus, hardness, and thermal conductivity of (U,Y)O2 decreased with increasing the Y content. 相似文献