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101.
Measurements have been made of complex impedance and sorbed water of polysodium phosphate. The resistance and its activation
energy decreases with an increase in the amount of sorbed water. The amount of sorbed water is strongly affected by the Na2O/P2O5 mol ratio. The humidity dependence of the activation energy and the resistance is lowered by decreasing the average chain
length of polysodium phosphate. This results in an increase in the amount of sorbed water. Especially, in low humidity conditions,
the decrease in the resistance and the activation energy are achieved by increasing the concentration of the strongly acidic
PO-H group. These improvements can not be achieved by increasing the Na2O/P2O5 mol ratio. In a humid atmosphere, the resistance of the film, in which the Na2O/P2O5 mol ratio is less than 0.8, is inversely proportional to the concentration of the strongly acidic PO-H group. 相似文献
102.
Nobukata H. Takagi S. Hiraga K. Ohgishi T. Miyashita M. Kamimura K. Hiramatsu S. Sakai K. Ishida T. Arakawa H. Itoh M. Naiki I. Noda M. 《Solid-State Circuits, IEEE Journal of》2000,35(5):682-690
We report a fast-programming, compact sense and latch (SL) circuit to realize an eight-level NAND flash memory. Fast programming is achieved by supplying optimized voltage and pulsewidth to the bit lines, according to the programming data. As a result, all data programming is completed almost simultaneously, and 0.67-MB/s program throughput, which is 1.7 times faster than conventional program throughput, is achieved. The compact layout of the SL circuit is made possible by four 3-bit latches sharing one unit of the read/verify control circuit. Using these techniques, we fabricated a 144-Mb, eight-level NAND flash memory using a 0.35-μm CMOS process, resulting in a 104.2-mm2 die size and a 1.05-μm2 effective cell size 相似文献
103.
Takeshita T. Shibata Y. Ito T. Sakai Y. Okamoto M. Tohmori Y. 《Quantum Electronics, IEEE Journal of》2001,37(12):1636-1642
A laser with a reverse-V-shape layer exhibits a circular beam spot and low threshold current. The beam aspect ratio of the reverse-V-shape laser is clarified to be insensitive to reverse-V-shape width. The reverse-V-shape layer consists of a strained active layer and a passive guide layer, which leads to a low threshold current. The reverse-V-shape laser is attractive as an optical source for optical-communication and information systems 相似文献
104.
The anisotropic flexural strengths, static Young's moduli and the corresponding fracture toughnesses were measured for the three orthogonal fracture surface orientations,S
ca
(interlaminar cleavage),S
ba
andS
ab
(layer rupture across and along the layers, respectively), of an as deposited substrate-nucleated pyrolytic carbon. BothS
ca
delamination andS
ab
along-layer rupture produced smooth fracture surfaces with meanK
lc values (MPam1/2) of 0.53 forS
ca
and 0.93 forS
ab
, independent of notch length. A different type of behaviour was observed forS
bc
across-layer fracture. Delamination cracking during failure resulted in rough fracture surfaces, crack arrests, and high apparent toughness values dependent on sample size and crack length. The nature of this induced delamination toughening is discussed.On leave from Toyohashi University of Technology, Tempaku-cho, Toyohashi 440, Japan. 相似文献
105.
D Suzuki M Miyazaki K Jinde T Koji M Yagame M Endoh Y Nomoto H Sakai 《Canadian Metallurgical Quarterly》1997,52(1):111-119
The effects of UV radiation on humans and animals are receiving increasing attention and much interest has recently been focused on the environmental effects of UV A and UV B. This study compares the in vitro effects of UV A and UV B on the clonogenic survival of two human skin keratinocyte cell lines, HaCaT which are immortal but not tumorigenic and HPV-G transfected keratinocytes which form non malignant tumours in nude mice. The effects were also studied on an EPC fish cell line. The aim of the work was to establish if similar initial and delayed survival responses occurred in both species. The cells were exposed to ultraviolet lamps emitting maximally at 365 nm (UV A) and 302 nm (UV B). Clonogenic survival was determined at appropriate times post exposure. Results for the initial survival curves show that the HaCaT and HPV-G cells did not show any appreciable difference in their response to UV A but the EPC cells were more sensitive at doses < 3000 Jm-2. The EPC cells were more sensitive to UV B at doses < 200 Jm-2 in comparison to the human HaCaT and HPV-G cells with the HPV-G cells showing the most sensitivity to UV B at doses > 200 Jm-2. The possible contribution of lethal mutations (delayed cell death) to the UV radiation response in the HaCaT and EPC cell lines was examined. The results showed that lethal mutations were expressed in the HaCaT cells following exposure to UV A and UV B but no lethal mutations were expressed in the EPC cells. 相似文献
106.
Harumi Yokokawa Natsuko Sakai Tatsuya Kawada Masayuki Dokiy 《Journal of the American Ceramic Society》1990,73(3):649-658
The thermodynamic properties of double oxides in rare earth-transition metal (V and Mn)-oxygen ternary systems have been collected and evaluated to examine their stability using chemical potential diagrams plotted as log (αA /αB ) vs log ( P (O2 )). The thermodynamic regularities of perovskites, pyrochlores, and other compounds have been discussed in terms of the effective ionic radii across a series of rare earths. The obtained regularities have been used to estimate tentatively the thermodynamic properties of some rare-earth vanadium and manganese oxides. 相似文献
107.
108.
Previously, we found that the newly isolated Clostridium sp. strain JC3 became the dominant cellulose-degrading bacterium in thermophilic methanogenic sludge. In the present study, the behavior of strain JC3 in the thermophilic anaerobic digestion process was investigated quantitatively by molecular biological techniques. A cellulose-degrading experiment was conducted at 55 degrees C with a 9.5 L of anaerobic baffled reactor having three compartments (Nos. 1, 2, 3). Over 80% of the COD input was converted into methane when 2.5 kgCOD m(-3) d(-1) was loaded for an HRT of 27 days. A FISH probe specific for strain JC3 was applied to sludge samples harvested from the baffled reactor. Consequently, the ratio of JC3 cells to DAPI-stained cells increased from below 0.5% (undetectable) to 9.4% (compartment 1), 13.1% (compartment 2) and 21.6% (compartment 3) at day 84 (2.5 kgCOD m(-3)d(-1)). The strain JC3 cell numbers determined by FISH correlated closely with the cellulose-degrading methanogenic activities of retained sludge. A specific primer set targeting the cellulase gene (cellobiohydrolaseA: cbhA) of strain JC3 was designed and applied to digested sludge for treating solid waste such as coffee grounds, wastepaper, garbage, cellulose and so on. The strain JC3 cell numbers determined by quantitative PCR correlated closely with the cellulose-sludge loading of the thermophilic digester. Strain JC3 is thus important in the anaerobic hydrolysis of cellulose in thermophilic anaerobic digestion processes. 相似文献
109.
K. Sakai T. Yoshida K. Kuba Y. Kato Y. Ichioka 《Journal of Infrared, Millimeter and Terahertz Waves》1987,8(3):307-316
Methods based on the Stark effect are described for dither-free frequency stabilization of the optically pumped submm laser. The CO2 pump laser was stabilized using a Stark Lamb dip signal of the submm lasant in an external Stark cell. An estimated frequency stability (Δf/f) better than ±1.4×10?8, for one hour recording, was obtained by this method. The frequency of the submm laser was stabilized using the d.c. and a.c. Stark effects for a metal-dielectric rectangular waveguide laser. An estimated frequency stability of ±6×10?8 was obtained for 119 μm line of CH3OH laser for one hour recording. 相似文献
110.
We investigated the reaction of butyraldehyde and benzylamine and analyzed the products to identify the components that produce
protein cross-linking in the reaction of butyraldehyde and proteins. When the mixtures of butyraldehyde and benzylamine were
incubated at pH 7 and 37°C for 48 hr, many reaction products other than 2-ethyl-2-hexenal and Schiff bases of butyraldehyde
and 2-ethyl-2-hexenal were produced. Fluorescent substance(s) were formed only in the presence of dissolved oxygen in the
reaction mixture. Three new nonflourescent products—d,e andf—were isolated, and their structures are suggested to be 2,9-dibenzyl-4,6,8-triethyl-7-propyl-2,9-diazabicyclo[3,3,1] nona-3-ene
(d), 1-phenyl-2-benzyl- 4,5,7-triethyl-6-propyl-1H,2H,3H,5H,6H,7H,8H-pyrido[1,2-clpyrimidine (e) and 1-phenyl-2-benzyl-4,5,7-triethyl-6-propyl-1H,2H,4aH,5H,6H,7H,8H-pyrido[1,2-c]pyrimidine (f). Formation of these compounds suggested that the protein, cross-linking with butyraldehyde is caused by the tretrameric
dialdehyde formed by repeated aldol condensation and Michael reaction of butyraldehyde. 相似文献