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831.
Quantum Boxes: Configuring Electronic States in an Atomically Precise Array of Quantum Boxes (Small 28/2016)
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Sylwia Nowakowska Aneliia Wäckerlin Ignacio Piquero‐Zulaica Jan Nowakowski Shigeki Kawai Christian Wäckerlin Manfred Matena Thomas Nijs Shadi Fatayer Olha Popova Aisha Ahsan S. Fatemeh Mousavi Toni Ivas Ernst Meyer Meike Stöhr J. Enrique Ortega Jonas Björk Lutz H. Gade Jorge Lobo‐Checa Thomas A. Jung 《Small (Weinheim an der Bergstrasse, Germany)》2016,12(28):3741-3741
832.
M Yamaguchi T Murakami Y Yasui S Otani M Kawai K Kishi H Kurachi K Shima T Aono Y Murata 《Canadian Metallurgical Quarterly》1998,252(2):363-367
PURPOSE: To identify imaging features at unenhanced helical computed tomography (CT) that help differentiate distal ureteral calculi from pelvic phleboliths. MATERIALS AND METHODS: Retrospective analysis was performed of 184 pelvic calcifications identified at unenhanced helical CT in 113 patients. The size, shape, and attenuation of each calcification were recorded in addition to the presence of a central lucency and the appearance of the adjacent soft tissues. With profile analysis, a graphic representation was generated of attenuation in each pixel along a line drawn through each calcification. RESULTS: Geometric configuration was seen in eight (21%) calculi but not in any phleboliths. Differences were significant (P < .0001) between the mean attenuation of calculi and that of phleboliths. Among phleboliths, none had a mean attenuation greater than 278 HU, 13 (9%) had a visible central lucency, 31 (21%) had a bifid peak at profile analysis, 30 (21%) had the "comet sign" (adjacent eccentric, tapering soft-tissue mass corresponding to the noncalcified portion of a pelvic vein), and three (2%) had the soft-tissue rim sign (edema of the ureteral wall). Among calculi, none had a central lucency, bifid peak, or comet sign, but 29 (76%) had the soft-tissue rim sign. CONCLUSION: Analysis of pelvic calcifications at unenhanced helical CT can help differentiate calculi from phleboliths. 相似文献
833.
Ishibashi A. Kawai T. Nakagawa S. Muto H. Katakai S. Hirotsu K. Nakatsuka T. 《Dielectrics and Electrical Insulation, IEEE Transactions on》1998,5(5):695-706
This review summarizes research on treeing phenomena, i.e. the formation of electrical trees and water trees, that has been undertaken in Japan for the development of 500 kV XLPE cable. Section 1 presents the results of factors affecting XLPE cable insulation breakdown under commercial ac and lightning impulse voltages. Section 2 verifies the phenomena of electrical tree formation in XLPE cable insulation using block samples and model cables, and gives the results of studies to determine the level electrical field stress initiation for such trees. Section 3 summarizes the results of studies on long-term aging characteristics, which is a particular problem under commercial ac voltages, while Section 4 explains how this research influenced the design of 500 kV XLPE cable insulation. All authors were members of `The investigation committee of fundamental process of treeing degradation' under IEEJ 相似文献
834.
Ryo Nakanishi Ryo Morikawa Masashi Kawai Takumi Nakahara Toshiyuki Toriyama 《Electrical Engineering in Japan》2023,216(3):e23443
This paper addresses semiconductor piezoresistive materials selection in MEMS engineering design. From the practical engineering point of view, it is important to understand piezoresistance properties of semiconductors even if less accuracy under feasibility design phase. However, piezoresistance is frequently analyzed based on first principle electronic band structure simulations by sophisticate physicists. Practical engineers not familiar with this simulation cannot directly apply useful information derived from the result of simulation. This paper provides practical prediction method for piezoresistance based on electronic band parameters obtained from the state-of-the-art solid-state physics. It is demonstrated that the crucial parameters which control the p-type shear piezoresistance coefficient π44 in diamond and zinc-blend single crystals are the inverse of square of bond length in unit cell atom, the square root of valence light hole mass, and the shear elastic compliance coefficient S44. 相似文献
835.
Y Okano M Akizuki H Kondo S Kawai Y Suzuki T Takeuchi Y Matsuoka Y Kawaguchi S Kashiwazaki 《Canadian Metallurgical Quarterly》1997,37(3):467-475
To characterize the American College of Rheumatology core set of disease activity measures for rheumatoid arthritis (RA) clinical trials (ACR core set measures) and the ACR definition of improvement of RA (ACR improvement definition), we studied 42 Japanese patients with active RA who were treated with DMARDs including mizoribine. Each patient's disease activity was assessed at the time of enrollment to the study and after 24 weeks using the ACR core set measures as well as the physical global assessment through the conventional measures. Twenty-five (60%) patients were discerned as showing improved by physicians through the conventional measures. This decision appeared to be based on improvement in Lansbury activity index (LAI) and C-reactive protein (CRP) value. Twelve of the 25 "improved" patients satisfied the ACR improvement definition. The 12 patients showed significant improvement in "outcome" measures including patients assessments of pain, disease activity, and physical function, compared to the 30 patients not satisfying the ACR definition. However, no significant differences were observed between these two groups in "process" measures including LAI, tender joint count, swallen joint count, or CRP value. In conclusion, the ACR core set measures including both process and outcome measures have potential to reflect clinical important changes on "real life" of patients with RA. 相似文献
836.
S Kusumoto I Jinnai K Itoh N Kawai T Sakata A Matsuda K Tominaga I Murohashi M Bessho K Harashima A Heshiki 《Canadian Metallurgical Quarterly》1997,99(3):649-655
Genetic sensitivity to 6-n-propylthiouracil (PROP) has been reported to predict hedonic response to sweet taste in both women and men. This study was based on a sample of 159 women of different ethnic backgrounds, mean age 27.0 years, and mean body mass index (BMI) 23.2. The women were classified as nontasters (n = 43), regular tasters (n = 70), or supertasters (n = 46) of PROP on the basis of their PROP detection thresholds and the scaling of 5 suprathreshold solutions of PROP and NaCl. Nontasters had thresholds > 1.8 x 10(-4) mol/L PROP and PROP/NaCl ratios < 1.60. Supertasters had thresholds < 3.2 x 10(-5) mol/L PROP and PROP/NaCl ratios > 1.60. Genetic sensitivity to PROP failed to predict sweetness intensity ratings or hedonic response profiles for sucrose solutions. Separating subjects into sucrose "likers" and "dislikers" failed to reveal any significant links to PROP nontaster, taster, or supertaster status in this all-female sample. 相似文献
837.
A transient natural convection develops along vertical plane Cu electrodes during the galvanostatic electrolysis. The time variations of both the concentration profile of CuSO4 and the velocity profile of a 0.6 M CuSO4 aqueous electrolyte were measured. The mass transfer rate of Cu2+ ion as well as the natural convective fluid motion was analyzed. The effect of electrode spacing on the transient natural convection was focused. The overshooting phenomenon caused by the transient diffusive and convective mass transfer rate was observed. Numerical simulation may provide as better understanding of the phenomena. 相似文献
838.
Yukio Watanabe Ikurou Kawai Akira Kowada Shodo Akita Yoshitetsu Itou Youichi Sono Mitsuo Koyanagi Mikio Yamamoto 《Nuclear Engineering and Design》2000,200(3):337-351
In Japan, the following five plants in operation use prestressed concrete containment vessels (PCCVs): Tsuruga #2 (in operation in 1987), Ohi #3 and #4 (in operation in 1991 and 1993, respectively), and Genkai #3 and #4 (in operation in 1994 and 1997, respectively). These plants have adopted the hemispherical dome type PCCV with two or three buttresses and unbonded prestressing system. For the above five PCCVs, lift-off tests in the in-service inspection have been carried out 1, 3 and 5 years after the beginning of operation. In addition, concrete strain and temperature have been measured periodically. This paper presents the in-service inspection methods and results of the lift-off tests and the measurement of concrete strain. The given results are as follows. Measured strain shows good agreement with calculated creep and shrinkage strain, so tendon tensile force can be predicted by the design method using calculated strain, and it also matches well the results of the lift-off tests. 相似文献
839.
The EuSe nanoparticles were prepared by the thermal reduction of Europium nitrate with new organic selenium compound, tetraphenylphosphonium diphenylphosphinediselenide (PPh4)(Se2P(C6H5)2), for the first time. EuSe nanoparticles were identified by the X-ray diffraction (XRD), the transmission electron microscope (TEM) and the energy dispersive X-ray spectroscopy (EDX) measurements. The average size of the EuSe nanoparticles was found to be 19 nm. The energy gap in EuSe nanoparticles of 19 nm was estimated by edge of absorption band, giving the energy gap of 1.86 eV. 相似文献
840.
Y. Ohdaira K. Kijima K. Terasawa M. Kawai H. Hori & K. Kitahara† 《Journal of microscopy》2001,202(1):255-260
Spin-sensitive optical near-field microscopy and spectroscopy are proposed based on the study on the conserved quantities in optical near-field interactions of atoms with dielectric surfaces. A two-step photoionization spectra of Cs atoms resolving hyperfine structures are demonstrated near a planar dielectric surface by using evanescent waves. These techniques of state/spin-selective excitation and highly sensitive detection, combined with the techniques of optical pumping, will open up possibilities of space- and polarization-sensitive detection of optical near‐fields using atomic probes. This novel method provides us with a useful technique for the observation of polarization nature of the optical near-field and controlling the spin states of mesoscopic electronic systems. 相似文献