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961.
Ju Young Lee Hong Seung Kim Chung-Hyun Lee Hyung Koun Cho Bo Hyun Kong 《Thin solid films》2009,517(17):5157-1130
We report the effects of thermal annealing in air and N2 ambient on the structural, optical, and electrical properties of zinc oxide (ZnO) films deposited on a p-GaN substrate. Also, we report on the fabrication and device characterization of heterojunction light-emitting diodes based on the n-ZnO/p-GaN systems. In the case of N2 ambient, room-temperature electroluminescence (EL) in the violet region with peak wavelength 400 nm was observed under forward bias. In air ambient, EL spectrum consisted of a broad band from 400 nm to 700 nm due to the Ga-O mixed region formed interface between the ZnO and GaN layer. 相似文献
962.
A useful model for general time-varying channels is a finite state Markov chain. In this paper, maximum likelihood sequence estimation (MLSE) for signals over finite state Markov channels (FSMCs) is studied. Also studied is the maximum a posteriori (MAP) channel state estimation. When coded signals with interleaving are transmitted, the channel estimates can be used to make soft-decision decoding. The error performance of the proposed sequence and channel state estimation schemes are evaluated through computer simulations. The effect of channel modeling error is also discussed 相似文献
963.
964.
Creep behavior of cold-rolled nanocrystalline pure copper 总被引:3,自引:0,他引:3
The creep of cold rolled nanocrystalline Cu has been investigated at 20–50 °C. The most reasonable stress exponent is found to be 2, the corresponding activation energy is 0.82 eV. The results imply that the creep is possibly associated with grain boundary sliding. The increase of threshold stress after rolling is associated with the increase of microstrain. 相似文献
965.
井间直达波层析成像的井斜校正研究与应用 总被引:3,自引:0,他引:3
在钻井过程中由于地层倾斜等原因,导致井的轨迹不是过井口的垂线,而是一条空间曲线,这就造成井间地震成像计算所用的初至旅行时存在偏差,影响成像精度。为此,本文提出了解决井斜校正的方法。通过对合成井问地震记录和实际记录进行试算,结果表明,该方法能够解决井斜造成的直达波旅行时误差,可提高速度反演的精度。 相似文献
966.
新型噻吩脱硫剂的研究 总被引:4,自引:1,他引:3
利用以活性炭作载体的脱硫剂脱除混合气中的噻吩,该脱硫剂可再生使用。对硫容、放硫现象、再生方法进行了讨论。 相似文献
967.
968.
GK Abruzzo AM Flattery CJ Gill L Kong JG Smith VB Pikounis JM Balkovec AF Bouffard JF Dropinski H Rosen H Kropp K Bartizal 《Canadian Metallurgical Quarterly》1997,41(11):2333-2338
The in vivo activity of the Merck antifungal echinocandin drug candidate MK-0991 (L-743,872) was evaluated in mouse models of disseminated candidiasis, aspergillosis, and cryptococcosis. The echinocandins are potent inhibitors of 1,3-beta-D-glucan synthase. Two models of disseminated candidiasis were used. In a Candida albicans mouse survival model with both DBA/2N and CD-1 mice, estimates of the 50% effective doses (ED50s) of MK-0991 were 0.04 and 0.10 mg/kg of body weight/dose at 21 days after challenge, respectively. In a C. albicans target organ assay (TOA) with DBA/2N mice, MK-0991 at levels of > or =0.09 mg/kg/dose significantly reduced the numbers of C. albicans CFU/g of kidneys compared to the numbers in the kidneys of control mice from 1 to 28 days after challenge. Even when given as a single intraperitoneal dose either 30 min or 24 h after challenge, MK-0991 was effective and significantly reduced the numbers of C. albicans CFU/g of kidney compared to those in the controls. MK-0991 was >300-fold less active when it was administered orally than when it was administered parenterally. MK-0991 was efficacious in mouse TOAs against other C. albicans strains and Candida species including Candida tropicalis, Candida (Torulopsis) glabrata, Candida lusitaniae, Candida parapsilosis, and Candida krusei. MK-0991 was ineffective against disseminated Cryptococcus neoformans infections. In the model of disseminated aspergillosis in mice, MK-0991 at doses of > or =0.02 mg/kg/dose significantly prolonged the survival of DBA/2N mice, with estimates of the ED50 and ED90 of MK-0991 being 0.03 and 0.12 mg/kg/dose, respectively, at 28 days after challenge. MK-0991 is a potent, parenterally administered therapeutic agent against disseminated candidiasis and aspergillosis that warrants further investigation in human clinical trials. 相似文献
969.
演变中的有机建筑——非线性有机建筑笔记 总被引:1,自引:0,他引:1
从20世纪有机建筑发展的几个重要节点论述其发展演化规律,以当代科学的视野,构建非线性有机建筑观,用以指导未来建筑创作与实践。 相似文献
970.