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231.
Kudo K. Miyake Y. Hirayama H. Tamura S. Arai S. Suematsu Y. 《Photonics Technology Letters, IEEE》1992,4(10):1089-1092
A room temperature CW operation of Ga0.3In0.7As/GaInAsP/InP GRINSCH compressive strained MQW lasers with 30~60 nm wide wire active region was achieved. This device was fabricated by two-step LP-OMVPE growths on p-type InP substrate and wet chemical etching. Threshold current as low as 53 mA ( L =910 μm, J th=2.9 kA/cm2) was obtained at RT-CW condition. The spontaneous emission peak and the lasing wavelength of strained MQW wire lasers exhibited approximately 20-meV blue shift from those of MQW film lasers cut out from the same wafer 相似文献
232.
We propose a new cone-beam shift-variant filtered backprojection (FBP) method for non-planar orbit data acquisitions. The new method is exact, fast and stable to discretization errors. It is based on the hybrid FBP framework whose key feature is to combine the shift-variant filtering with the ramp filtering to produce the filtered projections. We show that an adequate combination of the two filterings allows us to minimize contributions of the time-consuming and numerically unstable shift-variant filtering. We demonstrate the performances of the new method by simulation studies. We also apply the new method to real x-ray data acquired from our experimental system of monochromatic computed tomography. 相似文献
233.
Highly crystalline monoclinic scheelite BiVO4 powders are synthesized from aqueous Bi(NO3)3 and NH4VO3 solutions over a wide range of pH by a hydrothermal process. BiVO4 powders with various morphologies, surface textures, and grain shapes are selectively synthesized by adjusting the pH. The dependence of the Raman peak position and intensity on the synthesis conditions indicates that the symmetry distortions in the local structure of the synthesized BiVO4 are affected by the preparation conditions. These variations in the local structure result in the modification of the electronic structure of BiVO4, which results in a blue‐shift in the UV‐vis absorption spectrum of hydrothermally synthesized BiVO4 in comparison with a well‐crystallized sample prepared by homogeneous coprecipitation. The photocatalytic activities for O2 evolution from an aqueous AgNO3 solution under visible‐light irradiation are strongly dependent on the pH used in the synthesis. The differences in the photocatalytic activities between BiVO4 samples prepared under various conditions is attributed to the degree of structural distortion, leading to differences in the mobility of photogenerated holes formed in the valence band, which consists of Bi 6s and O 2p orbitals. 相似文献
234.
235.
This paper investigates 3D image reconstruction from truncated cone-beam (CB) projections acquired with a helical vertex path. First, we show that a rigorous derivation of Grangeat's formula for truncated projections leads to a small additional term compared with previously published similar formulations. This correction term is called the boundary term. Next, this result is used to develop a CB filtered-backprojection (FBP) algorithm for truncated helical projections. This new algorithm only requires the CB projections to be measured within the region that is bounded, in the detector, by the projections of the upper and lower turns of the helix. Finally, simulations with mathematical phantoms demonstrate that: (i) the boundary term is necessary to obtain high-quality imaging of low-contrast structures and (ii) good image quality is obtained even with large values of the pitch of the helix. 相似文献
236.
M Shinoda T Kudo M Suzuki Y Katayose N Sakurai H Saeki H Kodama K Fukuhara K Imai Y Hinoda S Matsuno 《Canadian Metallurgical Quarterly》1998,58(13):2838-2843
To reinforce cytotoxic activity and the targeting ability of lymphokine-activated killer cells with a T-cell phenotype (T-LAK) for adoptive immunotherapy against human bile duct carcinoma (BDC), staphylococcal enterotoxin A (SEA) was conjugated chemically with MUSE11 monoclonal antibody (MUSE11 mAb), directed to the MUC1 antigen, using N-succinimidyl 3-(2-pyridyldithio) propionate and 2-iminothiolane HCl. Both SEA-conjugated MUSE11 mAb (SEA-MUSE11) and the F(ab')2 of MUSE11 mAb (SEA-F(ab')2) showed significant enhancement of T-LAK cell tumor neutralization for MUC1 positive-target tumor cells, even with a concentration of 0.01 microg/ml at an E:T ratio of 5:1 in vitro. In this in vitro test, MUC1-positive BDC cells were observed to attach to surrounding T-LAK cells in the presence of SEA-MUSE11 or SEA-F(ab')2. Remarkable tumor growth inhibition was observed in BDC-grafted severe combined immunodeficient mice to which 2 x 10(7) T-LAK cells preincubated with 2 microg of SEA-MUSE11 or SEA-F(ab')2, together with recombinant interleukin 2 (500 IU), were administered i.v. for 4 consecutive days, when tumor size was 5 mm in diameter. These results point to a promising adoptive immunotherapy for patients with BDC. 相似文献
237.
238.
A Yoshizawa N Kobayashi K Kudo J Kabe N Ishiwa K Inagaki T Arai H Niino 《Canadian Metallurgical Quarterly》1996,34(12):1395-1400
A 52-year-old woman was admitted to our hospital because of repeated episodes of pneumonia in the middle lobe. She had also experienced coughing during meals. The history and chest CT findings suggested the presence of a bronchoesophageal fistula. An upper GI series revealed a fistula between an esophageal diverticulum and the superior segment bronchus of the right lower lobe. Fiberoptic bronchoscopy done immediately after the upper GI series revealed barium sulfate leaking from the superior segment bronchus of the right lower lobe into the middle lobe bronchus. These findings indicated that the repeated pneumonia in the middle lobe was caused by a congenital bronchoesophageal fistula. Examination of the resected fistula showed that it was a Braimbridge type I bronchoesophageal fistula. Although of at least 49 cases of congenital bronchoesophageal fistulas with esophageal diverticula have been reported in the Japanese medical literature, we know of no previous case in which such a fistula was associated with middle-lobe pneumonia. 相似文献
239.
S Sakamoto T Mori K Sawaki S Sassa S Suzuki Y Sugiura H Kudo N Kasahara H Nagasawa 《Canadian Metallurgical Quarterly》1993,22(2):119-124
We recorded frontal, central and parietal somatosensory evoked potentials (SEPs) to median nerve stimulation in 20 patients with Huntington's disease (HD) and in a group of normal controls. Two stimulus repetition rates, 1 Hz and 5 Hz, were employed. In HD patients the early cortical potentials (latency range 20-30 ms) at all 3 recording locations were replaced by a widespread, broadly configured N20-25 deflection, while later potentials at 40-80 ms did not significantly differ from those of normals. In contrast to the early P22, P27 and N30 potentials in normals, the N20-25 potential in the patients was not significantly modified by changing the stimulus repetition rate. At 40-80 ms the stimulus rate effects were similar in the patients and normals. The results show that early pre- and postcentral SEPs are both pathological in HD, while later frontal and parietal components can be totally preserved. The early N20-25 in HD is possibly a subcortical potential, seen due to unmasking in the absence of early cortical deflections. 相似文献
240.