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151.
Kai Wang Xiao-Dong Du Kuk-Tae Youn Yasunori Hayashi Chan Gyu Lee Bon Heun Koo 《Metals and Materials International》2008,14(6):689-693
The impact-wear properties of low carbon high manganese alloy steel were tested under three different impact energies (0.7
J, 1.2 J and 1.7 J) using a modified MLD-10 wear tester. SEM inspection of the wear surface and subsurface optical metallographic
analysis reveal the impact wear mechanism. Under corrosive conditions we observe a shift from single micro-cutting to impact-flaking,
after the appearance of vertical section micro-cracks, while at higher impact energies fatigue corrosion and abrasion are
observed. 相似文献
152.
A clear-view display and printing device is proposed utilizing a new bubble-domain shift register which has triangular patterns etched into the surface of a magnetic crystal. The geometrical and materials requirements for the clear-view shift register are analyzed. The etched-out triangular pattern is shown to provide the unidirectionality of bubble motion under an oscillating bias field just as the triangular Permalloy overlay does. An etched depth of one-tenth of the plate thickness and an etched gradient of about unity are shown to be sufficient for the expected shift-register operation. 相似文献
153.
This paper describes a business intelligence application of neural networks in analyzing consumer heterogeneity in the context of eating-out behavior in Taiwan. We apply a neural network rule extraction algorithm which automatically groups the consumers into identifiable segments according to their socio-demographic information. Within each of these segments, the consumers are distinguished between those who eat-out frequently from those who do not based on their psychological traits and eat-out considerations. The data set for this study has been collected through a survey of 800 Taiwanese consumers. Demographic information such as gender, age and income were recorded. In addition, information about their psychological traits and eating-out considerations that might influence the frequency of eating-out were obtained. The results of our data analysis show that the neural network rule extraction algorithm is able to find distinct consumer segments and predict the consumers within each segment with good accuracy. 相似文献
154.
G Wu T Mochizuki TC Le Y Cai T Hayashi DM Reynolds S Somlo 《Canadian Metallurgical Quarterly》1997,45(1):220-223
The gene responsible for the second form of autosomal dominant polycystic kidney disease, PKD2, has recently been identified. We now describe the cloning, genomic localization, cDNA sequence, and expression analysis of its murine homologue, Pkd2. The cloned cDNA sequence is 5134 bp long and is predicted to encode a 966-amino-acid integral membrane protein with six membrane-spanning domains and intracellular NH2 and COOH termini. Pkd2 is highly conserved with 91% identity and 98% similarity to polycystin-2 at the amino acid level. Pkd2 mRNA is widely expressed in mouse tissues. Pkd2 maps to mouse Chromosome 5 and is excluded as a candidate gene for previously mapped mouse mutations resulting in a polycystic kidney phenotype. 相似文献
155.
A Hayashi H Ito K Shomori H Ohdan K Yano T Asahara 《Canadian Metallurgical Quarterly》1997,47(8):518-524
The present study was conducted to examine the histopathological changes of rat liver grafts in the early post-transplantation period. A total of 44 orthotopic liver transplantations were performed using cuff techniques without anastomosis of the hepatic artery. They were divided into four groups: (i) group 1 (syngeneic, Lewis-->Lewis; n = 10); (ii) group 2 (allogeneic, ACI-->Lewis; n = 20); (iii) group 3 (allogeneic with immunosuppression, ACI-->Lewis; n = 12); and (iv) long-surviving grafts (PVG-->Lewis; n = 2). The histological findings were classified into four categories: (i) mild dilatation of Disse's spaces due to ischemia; (ii) bile duct proliferation; (iii) acute rejection; and (iv) zonal necrosis. Bile duct proliferation occurred on day 6 in all three groups and in one of the two long-surviving grafts (120 days). Acute rejection occurred on day 3 and progressed in groups 2 and 3. Zonal necrosis developed in group 2 after day 6, while acute rejection subsided after day 4 in group 3 receiving 15-deoxyspergualin. A few single cell deaths or acidophilic bodies were variably noted. Most of these cells showed signals by in situ nick end-labeling in their nuclei, implying the cells were undergoing apoptosis. The number of apoptotic hepatocytes increased as the progress and decreased with the regression of acute rejection in group 3. Thus, the extent of hepatocytic apoptosis may reflect the magnitude of acute rejection. More frequent distribution of apoptotic hepatocytes in periportal areas suggests that apoptosis may be induced by a variety of pathological stimuli, including the direct cytotoxic effects of lymphocytes, various cytokines and local circulatory disturbances. 相似文献
156.
New transmission equipment employing a 1.55-μm distributed feedback laser diode (DFB-LD) to overcome fiber dispersion has been tested at environmental conditions using 1.3-μm zero-dispersion fiber cable on the undersea section of route F-400M. The DFB-LD's dynamic spectrum characteristics, in relation to power penalty, were examined and a suitable laser prebias control level was obtained. Field experimental transmission lines operated error free for a two-month period, and applicability to 1.55-μm 445-Mbit/s systems of over 100 km was shown. 相似文献
157.
The ideal low- and high-frequency capacitance-voltage curves of a semiconductor(2)-insulator-semiconductor(1) (SIS) structure were first calculated with the insulator thickness, conductivity types and doping concentrations in semiconductor(1) and semiconductor(2) as parameters. The effects of fixed oxide charge and interface trap charge on the low and high frequency capacitance-voltage curves were also calculated. It was found that the fixed oxide sheet charge density with its centroid and the order estimation of the interface trap charge density with its effective type in addition to the insulator thickness, conductivity types and doping concentrations in semiconductor(1) and semiconductor(2) could be estimated from measured low and high frequency capacitance-voltage curves of an SIS structure. 相似文献
158.
K Oka K Hayashi T Nakazato T Suzawa K Fujiwara T Saruta 《Canadian Metallurgical Quarterly》1997,36(10):700-704
A 40-year-old male, with a past history of hypertension but receiving no medical treatment, was referred. He manifested malignant hypertension (190/130 mmHg; Keith-Wagener III), renal dysfunction (serum creatinine, 3.8 mg/dl), and elevated plasma aldosterone (450 pg/ml) and active renin concentration (ARC, 104 pg/ml). His blood pressure was controlled with multiple antihypertensive agents and ARC thus decreased (4.3 pg/ml), but aldosterone remained elevated. Abdominal magnetic resonance imaging (MRI) revealed a right adrenal adenoma, and aldosterone-producing adenoma was confirmed by adrenal venous sampling. Primary aldosteronism very rarely develops to malignant hypertension, and even in that case ARC is suppressed. Therefore this is a rare case of primary aldosteronism complicated with malignant hypertension and high ARC. 相似文献
159.
Potassium tantalate powders were hydrothermally synthesized at 400 °C using Ta2O5 and KOH as starting materials with various KOH concentrations (0.1–1.0 M) and heating durations (2–48 h). A defect pyrochlore
phase of KTa2O5(OH)·nH2O, was obtained at low KOH concentration and short reaction time. The perovskite phase of KTaO3 predominated as the heating duration and the KOH concentration increased. Pure KTaO3 was obtained in 0.5–1.0 M KOH aqueous solutions and reaction times of 8–48 h. Heteroepitaxitial KTaO3 thin films were achieved on the (100) SrTiO3 substrate in 0.5 M KOH solution under supercritical water conditions. Based on the XRD, SEM-EDX and EBSP (Electron BackScatter
Pattern) results, epitaxial KTaO3 crystals were grown on the (100) oriented single-crystal SrTiO3 substrate. Synthesis of perovskite KTaO3 crystals in supercritical water employed significantly low KOH concentrations (<0.5 M), which was far less than the very
high concentrations (>7 M) required for conventional hydrothermal method. 相似文献
160.
S Mikami S Kawashima K Kanazawa K Hirata H Hotta Y Hayashi H Itoh M Yokoyama 《Canadian Metallurgical Quarterly》1997,81(4):504-511
Recent reports demonstrated the expression of inducible-type NO synthase in the heart of viral myocarditis. Since NO has multiple biological actions, a substantial amount of NO produced in the diseased heart may act either as a cytotoxic or as a cytoprotective molecule in the process of myocarditis. In the present study, we examined the effect of inhibition of NO synthesis on the mortality and the extent of myocardial injury in a murine model of coxsackievirus B3-induced myocarditis. We fed the infected mice drinking water containing a relatively low concentration (0.37 mmol/L) of N omega-nitro-L-arginine methyl ester (L-NAME) for 14 days after virus inoculation. This dose of L-NAME did not change virus titers in the heart. However, L-NAME-fed mice showed a significant reduction in mortality compared with those fed normal drinking water (nontreated mice). On the contrary, mice given a higher concentration of L-NAME (3.7 mmol/L) exhibited increased mortality. In addition, mice fed a low concentration of L-NAME showed reductions in the severity of heart failure and in the area of myocardial necrosis. Although systemic blood pressure was reduced in nontreated mice, in mice fed a low concentration of L-NAME, it was maintained at a level similar to that in uninfected control mice, L-NAME-treated mice also exhibited a reduction in the degree of inflammatory cell infiltration associated with decreased production of tissue prostaglandin E2 levels in the heart compared with nontreated mice. Therefore, NO is likely to be involved in the pathogenic mechanisms of myocardial injury and resultant cardiac dysfunction in a murine model of coxsackievirus B3-induced viral myocarditis. 相似文献