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11.
The effects of thermal treatment on Limulus amebocyte lysate (LAL) reagent were studied. Thermal resistances of enzymes and coagulogen in LAL reagent were evaluated by aggregometry and SDS-PAGE. Although enzyme activities of LAL reagent were completely lost after heating at temperatures above 60 °C for 10 min, gelating activities of coagulogen were retained even over 80 °C. Phenylmethanesulfonyl fluoride (PMSF; 1 mmol/mL), a strong non-specific serine-protease inhibitor, did not completely inactivate serine-protease activities of LAL. As a result, complete hydrolysis of coagulogen to coagulin was unexpectedly obtained. Solvent treatment of LAL was similar in effect to thermal treatment of LAL, but there were 2 problems: complete removal of solvent from samples and increased solution turbidity during preparation. To study the application of thermal-treated LAL, we conjugated it with titania particles. LAL-conjugated titania particles were obtained as small aggregates between titania nanoparticles and thermal-treated LAL (LAL-conjugated microbeads; LCM). When the mixture of LCMs and fresh LAL reagent was reacted with endotoxin an acute aggregation of LCMs was induced prior to the aggregate formation of LAL as monitored by stirring turbidimetry. This method, endotoxin microbeads aggregometry (EMA) may provide a rapid and sensitive method for endotoxin determination. 相似文献
12.
Michio Kitamura Shunsuke Kobayashi Katsumi Mori 《Journal of the Society for Information Display》2006,14(5):509-514
Abstract— A new optical method for determining the pretilt angle ψ0, particularly on twisted‐nematic (TN) liquid‐crystal (LC) cells, is proposed. ψ0 was rapidly determined with good reproducibility on a TN‐LC cell by using a rotating analyzer optical system, a twist angle Φ, the azimuth of the director at a substrate, ϕ0, and the retardation Δnd as known values. The thickness d was also determined simultaneously with ψ0. ψ0 and d were determined within minutes. ψ0 was previously determined to be in the range of 0.1° with a standard deviation of 0.01°; this was obtained by repeating the measurement 50 times. The principle behind the determination and the experimental set up are described in detail. 相似文献
13.
Fukuwatari T Toriochi M Ohta M Sasaki R Shibata K 《Shokuhin eiseigaku zasshi. Journal of the Food Hygienic Society of Japan》2004,45(1):1-7
Bisphenol A, a monomer of polycarbonate plastics, disturbed the conversion pathway of the amino acid tryptophan to the vitamin nicotinamide. The conversion ratio of tryptophan to nicotinamide was reduced to 1/15 by feeding a diet containing 1% bisphenol A. A putative disturbing reaction is kynurenine-->3-hydroxykynurenine, which is catalyzed by kynurenine monohydroxylase. This is an FAD-enzyme and requires NADPH as a coenzyme. Styrene monomer (1% addition to a normal diet) did not affect the food intake or the body weight, but slightly reduced the conversion ratio of tryptophan-nicotinamide. 相似文献
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Takehiro Matsunaga Yoshio Nakayama Mitsuaki Iida Senzo Oinuma Noboru Ishikawa Katsumi Tanaka 《Propellants, Explosives, Pyrotechnics》1992,17(2):63-69
Molecular properties of benzene nitro derivatives were investigated by using semi-empirical MO calculations. As the results, the molecular structures and the rotational barrier of the nitro group calculated by AM1 showed a good agreement with the experimental values. The heats of formation in gaseous and condensed phases were obtained by considering isodesmic reactions. By this procedure, the heat of formation of hexanitrobenzene in solid phase was calculated to be +22.7 kcal/mol. The detonation parameters were also calculated by using four equations of state. The predicted detonation velocities showed a good agreement with the experimental values. 相似文献
16.
KatsumiIchitani 《材料热处理学报》2004,25(5):453-456
Heat transfer coefficients of the quench medium are necessary for heat-treatment simulation. Cooling characteristics of quenching oil vary with kinds and usage greatly. Users are selecting oil solutions that come up to their desired hardness and quenching distortion requirements. In particular cooling performance rises by agitation and decompression. Therefore we identified a heat transfer coefficient by usage and kinds of quenching oil. Cooling characteristics are different greatly by a kind of quenching oil. A difference of a cooling characteristic by a kind of oil depends on a temperature range of a boiling stage and the maximum heat transfer coefficient mainly. On the other hand, in a convection stage, there are few changes in a boiling stage. Even if quenching oil temperature is changed, heat transfer coefficients do not change greatly. When quenching oil stirred, heat transfer coefficients of vapor blanket stage and a convection stage rise, but there are a few changes in a boiling stage. When quenching oil is decompressed a temperature range of a high heat transfer coefficient moves to the low temperature side. In addition, a heat transfer coefficient in a vapor blanket stage comes down. For precision improvement of heat-treatment simulation, it is important that the heat transfer coefficient is calculated in conformity to the on-site use reality. 相似文献
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18.
Hideki Tanaka Daisuke Noguchi Akiko Yuzawa Tetsuya Kodaira Hirofumi Kanoh Katsumi Kaneko 《Journal of Low Temperature Physics》2009,157(3-4):352-373
We have investigated the applicability of simulations and theoretical techniques for exploring the selectivities of hydrogen isotopes. We have simulated the adsorption isotherms of H2 in an idealized carbon slit pore at 77 K by using the grand canonical Monte Carlo simulations with the Feynman-Hibbs effective potential (FH-GCMC) and the rigorous path integral method (PI-GCMC), and we obtained good agreement between the isotherms from both simulations. This suggests that FH-GCMC, which uses the approximative Feynman-Hibbs treatment, is as useful as PI-GCMC for exploring H2 adsorption at 77 K. Moreover, we show that the ideal adsorption solution theory (IAST) can predict the selectivity of D2 over H2 in the interstices of single-wall carbon nanotube (SWNT) bundles at 77 K (below 0.1 MPa) very well by comparing the obtained results with the mixture adsorption FH-GCMC simulations. This indicates that IAST is also applicable to the estimation of the selectivity of D2 over H2 at moderate pressures and at 77 K from experimental single-component adsorption isotherms. We also demonstrate that the FH-GCMC simulation can reproduce the experimental adsorption isotherms of H2 and D2 in aluminophosphate AlPO4-5 at 77 K. Finally, we analyze the selectivity of D2 over H2 by IAST with the experimental single-component adsorption isotherms of H2 and D2 at 77 K for a variety of adsorbents: AlPO4-5, activated carbon fibers (ACFs), HiPco SWNT, and SWNHs. The selectivities predicted by the experimental adsorption data based on the results from the FH-GCMC simulations are presented and discussed. 相似文献
19.
T. Katsumi H. Kodama T. Matsuo H. Ogawa N. Tsuboi K. Hori 《Combustion, Explosion, and Shock Waves》2009,45(4):442-453
A new composition of hydroxylammonium nitrate based solution containing ammonium nitrate, methanol, and water was developed
for monopropellant in a reaction control system (RCS) as an alternative to conventional hydrazine. In comparison with hydrazine,
this solution has a 20% higher specific impulse, 1.4 times higher density, and lower freezing point and toxicity. The linear
burning rate of the solution is moderate at the operating pressures of RCS thrusters. It was found that the linear burning
rate had some characteristics whose mechanisms had not been understood. The combustion mechanism of this solution was investigated.
The burning behavior was observed using a medium speed camera, and a temperature profile for the combustion wave was measured
with a 2.5 μm diameter thermocouple. From these results, the instability of the liquid-gas interface may trigger a sudden
increase in the burning rate, and methanol was found to be effective in reducing the bubble growth rate in the solution. The
reactivity of several catalysts was evaluated in an open-cup test, and the S405 catalyst for hydrazine showed the best performance
among them. Thruster tests were conducted using the S405 catalyst with variation in the propellant mass flow rate, catalyst
bed configuration, and length-to-diameter ratio of the combustor. As a result, parameters were determined that ensured long
operating time. The model thruster operated stably for up to 100 sec with a specific impulse I
sp = 240 sec, which corresponds to a 90% efficiency.
__________
Translated from Fizika Goreniya i Vzryva, Vol. 45, No. 4, pp. 109–120, July–August, 2009.
An erratum to this article can be found at 相似文献
20.