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81.
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Boron ions (11B+ of 3·7 to 7·4 × 1011/cm2 were implanted at 60–120 keV into the channel region of p-channel MNOS double layer insulated gate field effect transistors through 920–940 Å of SiO2 and various thicknesses (300–1800 Å) of Si3N4 deposited on SiO2. Subsequent annealing was performed in a nitrogen atmosphere at 1000°C for 30 min. Acceleration energy, implant dose and Si3N4 thickness dependences of the shift of the threshold voltage showed good agreement with the calculated results based on Ishiwara and Furukawa's theory for distribution of implanted atoms in the double layered substrate, using the projected ranges and standard deviations larger than LSS predictions by the factor of 1·2 for SiO2 and 1·3 for Si3N4, respectively. The results on the gain terms and the breakdown voltages were qualitatively the same as those of 11B+-implanted p-channel MOS transistors. 相似文献
83.
A cytochrome P-450 from adult pig testicular microsomes was purified to a specific content of 12 nmol P-450/mg protein. P-450 has a minimum molecular weight of 46000 +/- 1000, as judged on sodium dodecyl sulfate polyacrylamide gel electrophoresis. Adult testicular P-450 is prepared in the low-spin form with an absorbance maximum at 417 nm. The substrate-induced difference spectrum with progesterone is a typical I difference spectrum. P-450 was incorporated into liposomal membranes composed of phosphatidylcholine, and 17 alpha-hydroxylase activity was shown to amount to 15.5 nmol product/min/nmol of P-450. Furthermore, testicular cytochrome b 5 did not increase the 17 alpha-hydroxylase activity, and the activity was largely inhibited by the addition of sodium cholate, Emulgen 913 and testicular lipid. 相似文献
84.
The discharge behaviour of electrodeposited lead dioxide and lead electrodes was investigated under various conditions; the surfaces of the discharged electrodes were observed with a scanning electron microscope. Both the positive and negative electrodes were passivated by a covering of deposited lead sulphate crystals. The amount of lead sulphate required for passivation depended on the size of the crystals. 相似文献
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Kenjiro Meguro Tetsuya Kanbe Kunio Esumi 《Journal of the American Oil Chemists' Society》1983,60(5):1050-1052
The surface tensions of a mixed system of sodium tetradecyl sulfate (STS) and a series of polyoxyethyleneglycol-n-dodecyl ethers (nED) were measured at temperatures of 30 and 40 C, respectively. When the STS concentration was fixed, the
surface tension curves of the mixed system showed a flat portion in the range of which the mixed micelles would be formed.
With a decrease of the added STS concentration, the length of the flat portion in these curves decreased gradually, and finally
disappeared in the presence of 0.05 mM STS. Furthermore, when the concentration of STS was fixed at 1.0 mM, which is below
the critical micelle concentration (CMC), the flat portion length in the surface tension curves de-creased with decreasing
ethylene oxide chain length in nED and with increasing temperature. The influence of increment of temper-ature was comparable
to that for reducing the length of ethylene oxide chain in nED. 相似文献
90.