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81.
We applied a Mo/B4C multilayer coating to a laminar holographic grating with 2400 grooves/mm and a 1-m radius of curvature. By use of synchrotron soft x rays the multilayer-coated grating was evaluated to have diffraction efficiencies of 3.1% and 0.017% for s- and p-polarized radiation, respectively, at a 6.7-nm wavelength at a 45.35 degrees grazing angle of incidence in the +1 (inside) grating order. Thus the polarizance was estimated to be 98.9% at least. The zero-order peak was suppressed by the destructive interference caused by the groove profile. 相似文献
82.
Tanaka M Yoshimura M Suto M Yokota A Asano K Sukara E Tomita F 《Journal of Bioscience and Bioengineering》2002,93(6):531-536
A highly potent allelopathic factor, lepidimoide, was initially extracted from mucilage of germinated cress seeds. Polysaccharide extracted from okra (Abelmoschus esculentum Moench) is considered to have a similar structure to lepidimoide as its repeating unit. We therefore initiated the screening of enzymes capable of degrading okra polysaccharide into lepidimoide from endophytes. We discovered an endophytic fungal strain AHU9748 isolated from Coleus galeatus, which produced an oligosaccharide having similar properties to lepidimoide on thin layer chromatography. The physico-chemical data from ESI-MS, NMR spectra and other analyses also showed the purified product to be identical to lepidimoide. The strain AHU9748 was identified as a fungus belonging to the coelomycetes, closely related to the genus Colletotrichum, based on morphological characteristics and sequence analysis of the 18S rDNA and ITS region. 相似文献
83.
Kim YJ Yoshizawa M Takenaka S Murakami S Aoki K 《Journal of Bioscience and Bioengineering》2002,93(6):584-588
The two ammonia-assimilating enzymes glutamate dehydrogenase (GDH; EC 1.4.1.4) and glutamine synthetase (GS; EC 6.3.1.2) were synthesized steadily during the cell growth of Klebsiella pneumoniae F-5-2 that can utilize NH4+ and NO3- simultaneously under aerobic conditions. The enzymes were purified to homogeneity from cell extracts and characterized. The molecular mass of the purified GDH was 300 kDa with six identical 52-kDa subunits. GDH showed its maximal activity (aminating) at pH 8.0 and was stable between pHs 5.5 and 11.5. The enzyme was NADP-specific and strongly inhibited by Ag+. It catalyzed the amination of 2-ketovalerate, 2-ketoadipate, and 2-ketobutyrate, in addition to 2-ketoglutarate. The purified GS has a molecular mass of 470 kDa with eight identical 60-kDa subunits. GS showed its maximal activity at pH 8.0 and was stable between pHs 6.0 and 7.0. The enzyme was strongly inhibited by Fe3+, Hg2+, and Cu2+. 相似文献
84.
Makoto Ishii Kenji Saito Tomokazu Shiga Kiyoshi Igarashi Shigeo Mikoshiba Jooyul Lee Kyoung Ho Kang Heehwan Kim Changbae Park 《Journal of the Society for Information Display》2002,10(1):5-10
A hybrid AWD/AND drive technique has been developed in which an Address‐While‐Display (AWD) scheme is combined with an AND logic characteristic that gas discharges demonstrate. The AWD technique enables AC‐PDPs to be driven at high luminance, while the AND logic reduces the number of scan drivers by an order of magnitude. A detailed analysis of the addressing operation has been made. The hybrid drive utilizes the AND logic in two ways: (1) a combination of two voltage pulses and (2) a combination of a voltage pulse and discharge‐priming particles. It was found that the addressing operation requires the establishment of a discharge between the scan and data electrodes, and also between the scan and display electrodes. 相似文献
85.
Makoto Tsubota Yukinori Yasui Waichi Ogura 《Journal of Low Temperature Physics》1998,113(3-4):609-614
The quantum statistics of three-dimensional vortex filament in superfluid
4
He is investigated by the use of path integral techniques. The free energy evaluated in the saddle point approximation decreases abruptly at a certain critical value of the applied superflow velocity. This critical behavior is in quantitative agreement with the experimental result of vortex nucleation by a moving ion. The dissipation effects are also discussed within the damped harmonic oscillator approximation. 相似文献
86.
87.
A version of structured FORTRAN named STAR is introduced. STAR allows recursive subroutines. Implementation problems such as parameter passing by value and local variable stacking are discussed. The major difficulty in the preprocessor approach is debugging. We claim that execution profiles are strong debugging aids, and demonstrate how to debug a STAR program at source language level with the clue in the profiles plus assertion statements. We make use of a quicksort program as an example. 相似文献
88.
Lung from male and female rats fasted for 4 days were used. Phospholipid, phosphatidylcholine and its molecular species were
analyzed in lungs from these rats and effects of fasting upon the biosynthesis of phosphatidylcholine in lungs from both sexes
were determined using radioactive choline. The molecular species of phosphatidylcholine in both male and female rats did not
differ with fasting except the monoenoic species. Incorporation of choline into phosphatidylcholine in both male and female
rats significantly increased after fasting, but distribution of radioactivity in phosphatidylcholine yielded similar values
in each group. These results suggest that the decrease of saturated phosphatidylcholine content after fasting may be not due
to specific change in saturated phosphatidylcholine. 相似文献
89.
Makoto Isida 《Engineering Fracture Mechanics》1981,14(3):549-555
A rotating disk containing an internal crack at an arbitrary position is treated by using the eigen function expansions of the complex stress potentials, and determining the unknown coefficients from the boundary conditions expressed in terms of the resultant forces. Numerical calculations are done for various configurations and convenient formulae for the stress intensity factors are presented. 相似文献
90.
Kakimoto Y Naetoko Y Hara H Miyatake M Sato A Tatsuguchi H Takahata R Yamamoto R Joh T 《Shokuhin eiseigaku zasshi. Journal of the Food Hygienic Society of Japan》2004,45(3):165-174
A collaborative study involving 8 laboratories was conducted to evaluate a method for the simultaneous determination of pesticide residues in 6 types of fruits and vegetables (spinach, tomato, apple, radish, cabbage and carrot). The method of analysis was the same as reported by Kakimoto et al. in 2003. One hundred and thirty-nine pesticides were spiked by each of 8 laboratories at levels of 0.1 microg/g (pesticides analyzed by GC/MS) or 0.5 microg/g (pesticides analyzed by HPLC) into the 6 kinds of samples. Statistical analysis showed that 111 pesticides could be analyzed with practical precision by this method. For screening purposes, the method could analyze 118 pesticides. The median values of the limits of detection were 0.001-0.041 microg/g. The calibration curves were linear in the range of 0.5-5 microg/mL for most pesticides with median correlation coefficients of 0.983-1.000. 相似文献