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811.
A VHF excited hydrogen plasma was produced with a ladder-shaped electrode whose excitation frequency ranged up to 100 MHz for gas pressures of 40–200 mTorr and the plasma parameters were measured with a Langmuir probe. When the excitation frequency was increased, the electron density increased and the electron temperature decreased. The pressure dependence of the electron temperature at excitation frequencies of 65 and 100 MHz was different from the usual relationship: the electron temperature tended to increase with increasing pressure. 相似文献
812.
Effects of dietary methionine and cystine on lipid metabolism in hepatoma-bearing rats with hyperlipidemia 总被引:2,自引:0,他引:2
Abnormal lipid metabolism and its restoration by dietary methionine (Met) and cystine (Cys) were studied in Donryu rats subcutaneously
implanted with an ascites hepatoma cell line of AH109A. The hepatoma-bearing rats exhibited byperlipidemia characterized by
rises in serum triglyceride and cholesterol levels. Decreased lipoprotein lipase (LPL) activities in epididymal adipose tissue,
cardiac muscle, and gastrocnemius as well as increased fatty acid mobilization from adipose tissue were considered to be responsible
for the hepatoma-induced hypertriglyceridemia, while increased hepatic cholesterogenesis and decreased steroid excretion into
feces were thought to be responsible for the hepatoma-induced hypercholesterolemia. Dietary-supplemented Met or Cys reduced
the AH109A-induced hypertriglyceridemia with suppression of fatty acid synthesis in the host liver. Met restored the fall
of LPL activities, while Cys did not. Dietary Met or Cys also reduced the hypercholesterolemia with restoration of decreased
bile acid excretion into feces. These results suggest that dietary Met or Cys is hypolipidemic in the hepatoma-bearing rats
with slight differences in their modes of action. 相似文献
813.
Naohiko Kato Yasuhiko Takeda Kazuo Higuchi Akihiro Takeichi Eiichi Sudo Hiromitsu Tanaka Tomoyoshi Motohiro Toshiyuki Sano Tatsuo Toyoda 《Solar Energy Materials & Solar Cells》2009,93(6-7):893-897
Using Raman spectroscopy in addition to electrochemical impedance spectroscopy, we have clarified the deteriorated components of dye-sensitized solar cells (DSCs) module after the longest durability test in the world under outdoor working condition for ~2.5 years. It was confirmed that the N719 dye-adsorbed TiO2 electrode and carbon counter electrode were almost stable; therefore, the photocurrent (Jsc) was maintained during the outdoor working. The photovoltages (Voc) and the filling factors (FF) slightly decreased due to the increase of the Nernst diffusion impedance of triiodide (I3?), resulting from the change of the components in the electrolyte. 相似文献
814.
First-principles molecular orbital calculations using discrete–variational (DV)-Xα method are carried out on the model clusters of graphite and alkali–metal graphite intercalation compounds MCx(M=Li, Na, K, Rb, and Cs). Results of the calculations are used so as to simulate the experimentally observed near-edge X-ray-absorption fine-structures (XANES) and ultraviolet photoelectron spectra. For the clusters of graphite and KCx, the calculated partial electronic densities of states (PDOSs) are in good agreement with the experimental C K-edge and K K-edge XANES spectra, respectively. Furthermore, the accordance between the calculated DOSs and the observed UPS spectra of graphite and RbCx is also satisfactory. It is shown that the Fermi level is pushed up into the conduction band of graphite by doping alkali metals. 相似文献
815.
Shiraishi K. Kawasaki N. Yoda H. Watanabe K. Umetsu M. Hitomi T. Muro K. 《Lightwave Technology, Journal of》2009,27(7):864-870
A new scheme for lensed fibers with a high focusing power is proposed. The new lensed fiber has a high-index layer coated (HILC) on a convex-shaped endface of a single-mode fiber (SMF). Numerical investigation shows that, by coating a 10-mum-thick film with refractive index of 3.7, the lensed fiber can contract the beam diameter of the propagating mode from 10.4 mum at the wavelength of 1.55 mum, to 1.2 mum. The enhanced focusing effect of the lensed fiber has been confirmed experimentally by coating an a-Si:H film on the lensed endface. The measured focused spot diameter was as small as 1.6 mum, much the same as the wavelength. 相似文献
816.
B Kimura S Kawasaki T Fujii J Kusunoki T Itoh S J Flood 《Journal of food protection》1999,62(4):329-335
We evaluated the TaqMan Salmonella amplification/detection kit from PE Applied Biosystems, which uses a polymerase chain reaction (PCR) assay for rapid detection of Salmonella in food samples. This system uses the 5' nuclease activity of Taq DNA polymerase, which digests an internal fluorogenic probe to monitor the amplification of the target gene. The system's sensitivity and specificity were evaluated using 42 serotypes of 68 Salmonella strains isolated from fecal samples from patients in Tokyo, Japan, and 39 non-Salmonella strains in 22 genera. There were no false-negative or false-positive results. This PCR assay can detect 3 CFU per PCR tube of Salmonella in pure culture (120 CFU/ml of TSB culture). PCR signals were attenuated with artificially contaminated shrimp, but a similar detection limit was obtained. TaqMan's performance was tested with 100 meat and chicken samples purchased from stores in Tokyo. Overall, two of the DNA extraction protocols (the Chelex and EnviroAmp methods) worked equally well, with some exceptions. Of the 100 samples analyzed, 10 were positive for Salmonella with both conventional culture methods and the kit and 89 were negative with both. One sample was negative by the culture method but positive by the kit assay. These results indicate that TaqMan is a reliable and rapid method for Salmonella analysis in the food industry. With this system, food samples can be analyzed for Salmonella in less than 20 h. 相似文献
817.
818.
A new technique is proposed for integration of bulky optical components by means of a specific graded-index fiber in which the fundamental mode has a large mode-field diameter (MFD). A wide-beam propagating (WBP) fiber with the field diameter as large as 60 /spl mu/m was successfully fabricated, which will enable bulky optical components that have no wave-guiding structures to be embedded into a fiber circuit without any lenses. It was confirmed that a 5-mm-thick silicon plate, for example, can be integrated into the fiber with a loss of less than 1 dB. A hemispherically ended WPB fiber for much longer bulky components is also proposed. 相似文献
819.
820.
Furumiya M. Hatano K. Murakami I. Kawasaki T. Ogawa C. Nakashiba Y. 《Electron Devices, IEEE Transactions on》2001,48(9):1915-1921
A 1/3-in 1.3 M-pixel interline-transfer charge-coupled-device (IT-CCD) image sensor has been developed for digital-camera applications. A 0.25-μm-gap single-layer poly-Si is used for the CCD electrodes. The vertical CCD (V-CCD) of the image sensor has ten-phase metal wiring to enable various charge-transfer modes. A high-frame-rate skip mode (75 frames/s) and an advanced 3:1 interlaced-scan mode were developed and tested. A method of separately implanting boron ions for the V-CCD and horizontal CCD in single-layer electrode CCDs with small pixels, to maintain high charge-transfer efficiency, was developed. However, reducing pixel size degrades the light-gathering capability of the on-chip microlens, which occurs especially obliquely incident light, thus, reducing the sensitivity for a given camera-iris aperture (f-number). A new thin flattened-layer (3.5 μm thickness) microlens improved the sensitivity of the device. At f-number 1.4, for example, there was an 18% increase in sensitivity compared to that of the thick flattened-layer (5.0 μm thickness) microlens 相似文献