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101.
Koji Yamada Noboru Miura Chihiro Hamaguchi Norihiko Kamata 《Solid-state electronics》1989,32(12):1113-1117
Hot carrier magnetophonon resonances of n-type Si, short channel InP and p-type InSb were investigated in pulsed high magnetic fields up to 40 T. Using a recently developed high resolution technique in pulsed high fields, many new features of the hot carrier-phonon interactions in high magnetic fields were found. 相似文献
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Makris Angela P.; Rush Craig R.; Frederich Robert C.; Taylor Alisia C.; Kelly Thomas H. 《Canadian Metallurgical Quarterly》2007,15(2):123
Modafinil is indicated for the management of excessive daytime sleepiness; however, recent studies have examined a broad range of potential uses. Given that clinical uses of modafinil may be expanding, this study compared modafinil and d-amphetamine effects on subjective and performance measures. Across 11 sessions, 11 healthy adults were tested after oral doses of placebo (5 sessions), modafinil (1.75 mg/kg, 3.50 mg/kg, or 7.00 mg/kg), and d-amphetamine (0.035 mg/kg, 0.070 mg/kg, 0.140 mg/kg) under double-blind, randomized conditions. Assessments of cognitive performance and subjective effects were completed before drug administration, 30 min after drug administration, and at hourly intervals after drug administration for 5 hr. Modafinil increased ratings on the Amphetamine and Morphine Benzedrine Group scales of the Addiction Research Center Inventory (ARCI) and increased ratings on the Vigor and Total Positive scales of the Profile of Mood States. d-Amphetamine increased visual analog ratings of feeling stimulated and liking the drug and increased ratings on the Morphine Benzedrine Group scale of the ARCI. Both medications significantly reduced visual analog scale ratings of feeling sleepy, and modafinil decreased ratings on the ARCI Pentobarbital-Chlorpromazine-Alcohol Group scale. Both medications sustained performance that deteriorated across time on the Sternberg Number Recognition Test. Modafinil also enhanced performance rate on the Digit-Symbol Substitution Task above baseline levels and increased response rate on the Repeated Acquisition of Response Sequences Task. These results suggest that modafinil engenders alerting effects and increases performance in healthy non-sleep-deprived individuals comparable with that of d-amphetamine. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
104.
This paper presents a new concept for symmetric boundary element method (SBEM) applicable to 2-D steady-state and transit potential problems. Two kinds of SBEM formulations are derived. Symmetry is obtained simply through matrix manipulation, and no hypersingularity appears. Therefore, SBEM is much easier than the traditional symmetric Galerkin BEM. Compared with the traditional asymmetric BEM, the present SBEM can reduce the computational cost for time domain problems only. However, when applied to BEM/FEM coupling procedure, SBEM can reduce the computational cost for both steady-state and time domain problems. Three numerical examples are included to illustrate the effectiveness and accuracy of the present formulations. 相似文献
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ABSTRACT: Pulsed electric field (PEF) inactivation models for tomato juice lipoxygenase (LOX) were studied. Tomato juice was treated by PEF with the combinations of electric field strength (0, 10, 15, 20, 30, 35 kV/cm), PEF treatment time (20, 30, 50, 60, 70 μs), and PEF treatment temperature (10, 20, 30, 40, 50 °C). The first-order inactivation models, Hulsheger's model, Fermi's model, and the 2nd-order polynomial equation adequately described the LOX inactivation. Calculated D values were 161.0, 112.9, 101.0, and 74.8 μs at 15, 20, 30, and 35 kV/cm, respectively, at 30 °C. The activation energy for the inactivation of LOX by PEF was 35.7 kJ/mol. Applied electric field strength was the primary variable for the inactivation of LOX. 相似文献
107.
海上油井酸化后,油井返排液沉降分离得到含酸原油,后者进入电脱水器后常引起电脱水器跳闸。其原因是含酸原油(油包水型乳状液)的电导率过高,超过了电脱水器的安全工作电导率κw。对于现场所用的电脱水器,由设计参数计算出κw=0.43μS/cm。从某海上油田3口油井酸化后不同时间的返排液共取样40份,随机选出13份,沉降分离后得到13份含酸原油样,测得电导率范围在0.03~10000μS/cm。认为原油的含水率(应<18%)不是引起跳闸的原因,跳闸的主因是含酸原油的高电导率。研制了一种油溶性的碱性添加剂,其化学成份是碱金属、碱土金属氧化物或氢氧化物,以浓溶液形式加入含酸原油中,可使电导率降至κw以下。加入量由实验确定。表2参2。 相似文献
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电网无功补偿方式的探讨 总被引:1,自引:0,他引:1
概述了电网无功补偿的基本情况,并对几种无功补偿方式进行了技术分析,结合几种补偿方式的特点,提出了无功补偿配置原则。 相似文献