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101.
Abstract: Phase‐shifting digital holography is a useful method to measure the displacement distribution and the strain distribution of an object surface. The complex amplitude distribution of an object surface is obtained as the complex amplitude distribution at a reconstruction distance. It is, however, difficult to measure the reconstruction distance by actual measurement. We discovered that the standard deviation of the intensity on the reconstructed image becomes the maximum value when the reconstruction distance is the same as the actual optical path length. The displacement distributions are obtained for the x‐, y‐ and z‐directions. When the normal direction of an object surface inclines from the z‐direction, the displacements defined on the xyz‐coordinate system should be transformed into the object coordinate system. It is, therefore, required to develop a measurement method of the orientation of the object to obtain the parameters for transforming from the xyz‐coordinate system into the object coordinate system. In this paper, the method to identify the position and the orientation of a specimen using the standard deviation of the intensity distribution is proposed. 相似文献
102.
Boronized layer on steel is known to be formed by thermal diffusion of boron into the surface of steel improving corrosion-erosion resistant properties. Boronizing is carried out at temperatures ranging from 800 °C to 1050 °C and takes from one to several hours. There is one problem in this process, however, that the structure and properties of the base material are influenced considerably by the high temperature and long time of treatment. In order to avoid the aforementioned drawbacks of pack boronizing and laser-assisted boronizing, a better way is to activate the pack boronizing media and the workpiece with a high density power. The laser boronizing processes do not change the properties of the base material. In this study, the effect of laser characteristics was examined on the laser boronizing of carbon steel. After laser boronizing, the microstructure of the boride layer was analysed with an optical microscope and X-ray diffractometer (XRD). The mechanical properties of borided layer are evaluated using Vickers hardness tester and sand erosion tester. Results showed that the boride layer was composed of FeB and Fe2B with thickness ranging 200-300 μm. The laser boronizing process did not change the properties of the base material. 相似文献
103.
Sato H. Wada T. Ohbayashi S. Kozaru K. Okamoto Y. Higashide Y. Shimizu T. Maki Y. Morimoto R. Otoi H. Koga T. Honda H. Taniguchi M. Arita Y. Shiomi T. 《Solid-State Circuits, IEEE Journal of》1999,34(11):1571-1579
This paper describes a 0.25-μm, 64 K×36 bit pipelined burst SRAM using a 6.156-μm2 cell. It realizes over 500-MHz operation using a lower cost double metal process, Internal 16 K×144 organization by T-shaped bit line array reduces 20% of latency, 20% of active power, and 8.5% of die size. The low power also enables us to use lower cost thin quad flat type packages. Our solution to the soft error problem, a shallow triple well structure and four-transistor cell with stacked capacitor, improved soft error rate by 3.5 orders of magnitude compared with the conventional SRAM cell 相似文献
104.
Sumio Chono Yoshihiko Tauchi Kazuhiro Morimoto 《Drug development and industrial pharmacy》2013,39(1):125-135
ABSTRACTIn order to confirm the efficacy of liposomes as a drug carrier for atherosclerotic therapy, the influence of particle size on the distribution of liposomes to atherosclerotic lesions in mice was investigated. In brief, liposomes of three different particle sizes (500, 200, and 70 nm) were prepared, and the uptake of liposomes by the macrophages and foam cells in vitro and the biodistributions of liposomes administered intravenously to atherogenic mice in vivo were examined. The uptake by the macrophages and foam cells increased with the increase in particle size. Although the elimination rate from the blood circulation and the hepatic and splenic distribution increased with the increase in particle size in atherogenic mice, the aortic distribution was independent of the particle size. The aortic distribution of 200 nm liposomes was the highest in comparison with the other sizes. Surprisingly, the aortic distribution of liposomes in vivo did not correspond with the uptake by macrophages and foam cells in vitro. These results suggest that there is an optimal size for the distribution of liposomes to atherosclerotic lesions. 相似文献
105.
Takashi Wakuda Kazuo Azuma Hiroyuki Saimoto Shinsuke Ifuku Minoru Morimoto Ichiro Arifuku Masahito Asaka Takeshi Tsuka Tomohiro Imagawa Yoshiharu Okamoto Tomohiro Osaki Saburo Minami 《Journal of Functional Foods》2013,5(1):516-523
The effects of pear vinegar (PV), which was specially brewed for enhanced galacturonic acid content, on the DSS-induced ulcerative colitis (UC) mouse model were evaluated. PV improved clinical symptoms, colon inflammation, and histological tissue injury in the DSS-induced acute UC mouse model. Moreover, PV suppressed inflammation due to acute UC by suppressing the myeloperoxidase (MPO)-mediated activation of inflammatory cells such as leukocytes and decreasing the serum concentration of IL-6. Our results demonstrated the protective action of PV in the DSS-induced acute UC mouse model. On the other hand, commercial apple vinegar did not show a protective effect in the DSS-induced acute UC mouse model. Our findings indicate that PV may act as a new functional food for inflammatory bowel disease patients. 相似文献
106.
Hisato Tokoro Shigeo FujiiYasuhiro Kobayashi Shunsuke Muto 《Journal of Alloys and Compounds》2011,509(5):1378-1383
Magnetic fine particles of metallic Fe coated with graphitic carbon layers were synthesized by annealing Fe2O3 particles with carbon powders at 1673 K in nitrogen atmosphere. For comparison, SiC was added to Fe2O3. X-ray diffraction measurement showed that the lattice constants of Fe changed depending on the Si contents. Mössbauer spectroscopy confirmed that Fe-Si alloys were formed by the Si addition and that the iron carbide disappeared. Electron microscope images revealed that the thickness of carbon coating layers increased from 24 nm to 36 nm as a result of the Si addition. Soaking tests showed that the corrosion resistance of the carbon-coated Fe particles was improved by the addition of Si. The results suggest that Si caused C to leave the Fe cores and move to the surface to form a carbon coating. 相似文献
107.
M Otsuki K Hashimoto Y Morimoto T Kishimoto S Kasayama 《Canadian Metallurgical Quarterly》1997,46(12):2096-2101
Vascular cell adhesion molecule-1 (VCAM-1) has been shown to be highly expressed in atherosclerotic lesions. Although the soluble form of VCAM-1 (sVCAM-1) is detected in human sera, the relation between the degree of atherosclerosis and serum sVCAM-1 level has not been defined. In the present study, sVCAM-1 concentrations were measured in sera from 101 Japanese NIDDM patients. The mean +/- SD serum sVCAM-1 concentration in 26 patients with symptomatic atherosclerotic vascular diseases (789 +/- 187 ng/ml) was higher than that in 75 patients without the disease (664 +/- 175 ng/ml). Among the 101 NIDDM patients, 56 had atherosclerotic change of the carotid arteries, based on the evaluation by high-resolution B-mode ultrasonography. Their sVCAM-1 level was 759 +/- 201 ng/ml, higher than that in 45 patients without any detectable atherosclerosis of the carotid arteries (619 +/- 130 ng/ml). In addition, there was a positive correlation between sVCAM-1 concentration and thickness of the intimal plus medial complex (IMT) of the carotid arteries in the NIDDM patients (r = 0.41, P < 0.0001). Multivariate regression analysis revealed significant predictors of mean IMT value to be sVCAM-1 concentration (F = 62.88, P = 0.0001) and age (F = 9.59, P = 0.0026). By contrast, sVCAM-1 concentration was not increased in nondiabetic patients with atherosclerotic change of the carotid arteries (668 +/- 191 ng/ml; n = 36) compared with those without the atherosclerotic change (632 +/- 177 ng/ml; n = 28), and there was no correlation between sVCAM-1 level and IMT of the carotid arteries in the nondiabetic subjects. These results indicate that circulating sVCAM-1 may be a marker of atherosclerotic lesions in NIDDM patients with symptomatic and asymptomatic atherosclerosis. 相似文献
108.
This paper describes the formation of a third liquid phase in a phase transfer catalytic system in the presence of benzyl alcohol and potassium hydroxide, where dodecane and tetraalkylammonium bromide serve as organic solvent and catalyst, respectively. In this kind of system, a symmetrical ether (dibenzyl ether) was synthesized from benzyl chloride and benzyl alcohol at 323 K. In particular, the investigation demonstrates that the observed reaction rate constant depends on the length of the alkyl group of the catalyst. Tetrabutylammonium bromide exhibits the highest catalytic activity among the catalysts explored. With respect to the reuse of the third liquid phase, the results confirm that there is no decrease in phase transfer catalytic activity in three consecutive runs. 相似文献
109.
S Koizumi M Ishiguro I Ohsawa T Morimoto C Takamura K Inoue S Kohsaka 《Canadian Metallurgical Quarterly》1998,123(8):1483-1489
1. The effects of secreted forms of beta-amyloid-precursor proteins (APP(S)s) on the intracellular Ca2+ concentration ([Ca2+]i) were investigated in rat cultured hippocampal neurones. APP695S, a secretory form of APP695, attenuated the increase in [Ca2+]i evoked by glutamate. In addition, APP695S itself evoked an increase in [Ca2+]i in 1 or 2 day-cultured hippocampal cells, but not in 7 to 13 day-cultured cells. 2. Eighty-one percent of neurones which were immunocytochemically positive for microtubule-associated protein 2 responded to APP695S with an increase in [Ca2+]i. 3. APP695S induced a transient rise in [Ca2+]i even in the absence of extracellular Ca2+ and produced an elevation in inositol-1,4,5-trisphosphate (IP3) in a concentration-dependent manner from 100 to 500 ng ml(-1). In the presence of extracellular Ca2+, APP695S caused a transient rise in [Ca2+]i followed by a sustained phase at high [Ca2+]i, suggesting Ca2+ entry from the extracellular space. 4. The [Ca2+]i elevation was mimicked by amino terminal peptides of APPs, but not by carboxy terminal peptides. 5. These results taken together suggest that APP695S induces an increase in [Ca2+]i in hippocampal neurones through an IP3-dependent mechanism that changes according to the stage of development. 相似文献
110.
H Sawada H Morimoto A Wake Y Yamasaki Y Izumi M Kuroiwa S Osabe Y Imamura K Egami A Tsukamoto I Sanada T Kiyokawa F Kawano 《Canadian Metallurgical Quarterly》1998,39(11):1085-1091
Thirty patients (median age of 32 years; range, 6-61) with hematologic disorders received unmanipulated peripheral blood stem cell transplants from HLA-matched or one-antigen-mismatched related donors following myeloablative therapy for acute lymphoblastic leukemia (7), acute myelogenous leukemia (6), chronic myelogenous leukemia (8), myelodysplastic syndrome (3), or other disorders (6). Granulocyte colony stimulating factor (G-CSF) mobilized peripheral blood stem cells were collected from donors in 1 to 3 aphereses. The apheresis products contained mean counts of 11.3 x 10(8) (range, 3.8-17.2) nucleated cells/kg and 6.7 x 10(6) (range, 1.3-16.7) CD34+ cells/kg. Graft-versus-host-disease (GVHD) prophylaxis consisted of cyclosporin A plus methotrexate, or FK506 plus methotrexate. All patients received G-CSF following their transplant. Although 1 patient died of pneumonia 6 days after transplantation, the others demonstrated rapid engraftment. Median days to recovery to 500/microliter neutrophils and 20,000/microliter platelets were 13 (range, 8-21) and 14 (range, 1-23) days, respectively. The incidence of acute GVHD grade II-IV was 33%; chronic GVHD developed in 57% of the assessable patients. There were no episodes of graft failure or rejection. Nineteen patients (63%) were alive and in complete remission from 147 to 839 days following their transplant (median follow-up of 560 days). Further follow-up study will be required to assess the incidence of chronic GVHD and graft-versus-leukemia (GVL) effects. 相似文献