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排序方式: 共有622条查询结果,搜索用时 31 毫秒
1.
Akira Yamamoto Kentaro Teramura Saburo Hosokawa Tsunehiro Tanaka 《Science and Technology of Advanced Materials》2015,16(2)
The effect of SO2 gas was investigated on the activity of the photo-assisted selective catalytic reduction of nitrogen monoxide (NO) with ammonia (NH3) over a TiO2 photocatalyst in the presence of excess oxygen (photo-SCR). The introduction of SO2 (300 ppm) greatly decreased the activity of the photo-SCR at 373 K. The increment of the reaction temperature enhanced the resistance to SO2 gas, and at 553 K the conversion of NO was stable for at least 300 min of the reaction. X-ray diffraction, FTIR spectroscopy, thermogravimetry and differential thermal analysis, x-ray photoelectron spectroscopy (XPS), elemental analysis and N2 adsorption measurement revealed that the ammonium sulfate species were generated after the reaction. There was a strong negative correlation between the deposition amount of the ammonium sulfate species and the specific surface area. Based on the above relationship, we concluded that the deposition of the ammonium sulfate species decreased the specific surface area by plugging the pore structure of the catalyst, and the decrease of the specific surface area resulted in the deactivation of the catalyst. 相似文献
2.
Serum vanadium, aluminum, silicon and beta 2-microglobulin levels as well as the red cell count, hemoglobin and systolic blood pressure were simultaneously measured in 80 chronic hemodialysis patients. The serum vanadium level was positively correlated with the serum levels of aluminum, silicon and beta 2-microglobulin as well as the systolic blood pressure, and was inversely correlated with the red cell count and hemoglobin. The mean serum vanadium level was 18.4 +/- 7.6 ng/ml before hemodialysis and decreased to 13.0 +/- 5.30 ng/ml at the completion of dialysis. The dialysate vanadium level increased from 0.4 +/- 0.2 (inflow) to 1.0 +/- 0.4 ng/ml (outflow). It was concluded that vanadium was transferred from blood to dialysate when purified water was used in the preparation of the dialysate. 相似文献
3.
K Jin-no M Tanimizu I Hyodo Y Nishikawa Y Hosokawa H Endo T Doi K Mandai H Ishitsuka 《Canadian Metallurgical Quarterly》1998,82(7):1260-1267
BACKGROUND: Platelet-derived endothelial cell growth factor (PD-ECGF) is an angiogenic factor that is expressed in various cancer tissues. Little is known regarding plasma PD-ECGF levels in patients with chronic liver disease such as chronic hepatitis (CH), cirrhosis, and hepatocellular carcinoma (HCC) with cirrhosis. The expression of PD-ECGF in HCC tissues also remains to be clarified. METHODS: Plasma PD-ECGF levels in patients with chronic liver disease were determined with an enzyme-linked immunoadsorbent assay system using the mouse monoclonal antibodies specific to PD-ECGF. These were cross-sectionally compared among groups of normal persons, CH, cirrhosis, and HCC patients. The HCC patients were classified into two groups based on TNM stage: early and advanced stage disease groups. PD-ECGF expressions in HCC tissues were immunohistologically examined. RESULTS: The plasma PD-ECGF levels from the normal individuals and those with CH, cirrhosis, and HCC specimens were 4.2+/-0.5, 4.3+/-0.6, 4.6+/-1.1, and 6.0 +/-2.5 U/mL, respectively. The plasma PD-ECGF concentration was highest in HCC (P < 0.05). No significant difference was found among the normal subjects, CH, and cirrhosis specimens. Plasma PD-ECGF concentrations were significantly higher in the advanced stage disease HCC group compared with the early stage disease group (6.75+/-2.62 U/mL vs. 4.19+/-0.34 U/mL) (P < 0.05). Immunohistochemical expression of PD-ECGF in HCC cells increased significantly compared with normal liver cells (P < 0.05). CONCLUSIONS: Circulating PD-ECGF plasma level might be a new tumor marker for progression in patients with HCC. Immunohistological findings correspond to elevation of the plasma PD-ECGF in HCC patients. It is possible that increased production of PD-ECGF in HCC cells causes abundant neovascularization. 相似文献
4.
5.
Masahito Matsubayashi Takashi Hibiki Kaichiro Mishima Koji Yoshii Koji Okamoto 《Nuclear instruments & methods in physics research. Section A, Accelerators, spectrometers, detectors and associated equipment》2003,510(3):325-333
A fluorescent converter for fast neutron radiography (FNR) comprising a scintillator and hydrogen-rich resin has been developed and applied to electronic imaging. The rate of the reaction between fast neutrons and the converter is increased by thickening the converter, but its opaqueness attenuates emitted light photons before they reach its surface. To improve the luminosity of a fluorescent converter for FNR, a novel type of converter was designed in which wavelength-shifting fibers were adopted to transport radiated light to the observation end face. The performance of the converter was compared with that of a polypropylene-based fluorescent converter in an experiment conducted at the fast-neutron-source reactor YAYOI in the University of Tokyo. 相似文献
6.
Tsuyoshi Takahashi Masahito Kitou Michio Asai Mitsuyasu Kido Tomio Chiba Junzou Kawakami Yoshiaki Matsui 《Electrical Engineering in Japan》1994,114(2):18-33
Power system control equipment needs higher sensitivity and operational reliability. Advanced voltage control equipment is needed for reducing the frequency of tap changes and improving the characteristics (the relationship between the actual voltage and reference voltage) of the voltage to meet today's power system requirements. However, these objectives are in a trade-off relationship. Studies of voltage control derived from a knowledge base suitable for electric power systems can satisfy these objectives using fuzzy inference. Compared with corresponding conventional equipment, the new equipment improved the deviation of 30 min average voltage of 30 percent. This paper describes the design concept of new voltage control equipment using fuzzy inference. In addition, field test results are described along with rules of fuzzy inference, membership functions, and the deviation of 30 min average voltage through detailed simulation. 相似文献
7.
This paper investigates induced voltage characteristics from an overhead transmission line by applying a method of modeling of induced voltages proposed by the authors. EMTP simulation results obtained by the modeling method agree with analytical results obtained from a well‐known formula. The induced voltages are significantly dependent on the configuration of the overhead line. A horizontal line induces the largest voltage in a gas pipeline, and the voltage induced by a vertical twin‐circuit line is about 20% smaller than that induced by a vertical single‐circuit line. The method is applied to a real pipeline system and the simulation results show reasonable agreement with field test results. © 2008 Wiley Periodicals, Inc. Electr Eng Jpn, 164(1): 43–51, 2008; Published online in Wiley InterScience ( www.interscience.wiley.com ). DOI 10.1002/eej.20465 相似文献
8.
To examine the development of pancreatic fibrosis in alcoholics, the fibrosis types grouped according to Martin's classification were examined by immunohistochemistry using an antibody against alpha-smooth muscle actin (alpha-SMA). The initial stage of periacinar collagenization was also investigated by electron microscopy. The total incidence of pancreatic fibrosis at autopsy of the 29 alcoholics was significantly higher than that of the 40 non-alcoholics. Intralobular sclerosis was observed to be the most frequent type of fibrosis regardless of alcohol intake. No differences in the enhancement of alpha-SMA expression in each type of fibrosis were found between the alcoholics and non-alcoholics. Electron microscopically, myofibroblasts were found around acini in the early stage of periacinar collagenization, and were accompanied by numerous fine filaments (8-15 nm in diameter). The various changes in zymogen granules (ZG), lysosomes and lipid droplets were augmented in the acinar cells of alcoholics. Medium-density materials were also found in dilated rough endoplasmic reticulum (RER). The contents of ZG and RER occasionally leaked out. In conclusion, pancreatic fibrosis was increased in alcoholics; myofibroblasts may play an important role in the initial stage of periacinar collagenization; and the intracellular transport blockage of protein as represented by abnormalities of ZG, ER and lysosomes may contribute to the development of periacinar collagenization. 相似文献
9.
Laser Dressing of Metal Bonded Diamond Wheel 总被引:4,自引:0,他引:4
In this study, a laser beam is used as a non-contact thermal dressing tool for a bronze bonded diamond wheel. The pulsed-Nd:YAG laser beam is irradiated on the wheel surface and the bond material partially removed by laser irradiation only. In order to efficiently remove the bond material, it is necessary to direct an air jet on the spot irradiated by the laser so as to blow away the molten binder before it solidifies again. Less damage of diamond particles such as micro-cracks or graphitization occurs. In grinding with a laser-dressed wheel, the grinding forces are almost the same as those for a conventionally dressed wheel. Consequently, effective laser dressing can be expected with the associated dressing conditions. 相似文献
10.
Hikota Akimoto Osamu Ishikawa Gong-Hun Oh Masahito Nakagawa Tohru Hata Takao Kodama 《Journal of Low Temperature Physics》1991,82(5-6):295-316
Spin dynamics of3He-4He dilute solution have been studied in the collisionless regime by NMR methods. In cw NMR experiments, we observed spin waves in a magnetic field gradient. The frequency difference between the first mode and the others obeyed a two-thirds power law in the strength of the field gradient. By using a pulsed NMR method, nonlinear spin dynamics were studied. We observed the large amplitude spin waves after an rf pulse. The frequency of each spin-wave mode depended on the tipping angle. By using the parameter determined in the present experiment, the numerical calculated results based on Leggett-Rice theory are in good agreement with the results of the pulsed NMR experiments. 相似文献