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排序方式: 共有80条查询结果,搜索用时 31 毫秒
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Carlota Oleaga Andrea Lavado Anne Riu Sandra Rothemund Carlos A. Carmona‐Moran Keisha Persaud Andrew Yurko Jennifer Lear Narasimhan Sriram Narasimhan Christopher J. Long Frank Sommerhage Lee Richard Bridges Yunqing Cai Candace Martin Mark T. Schnepper Arindom Goswami Reine Note Jessica Langer Silvia Teissier Jos Cotovio James J. Hickman 《Advanced functional materials》2019,29(8)
33.
Mohammad Rajiullah Reine Lundin Anna Brunstrom Stefan Lindskog 《Computer Networks》2013,57(18):3967-3986
PR-SCTP, a partially reliable extension of SCTP, provides a flexible QoS trade-off between timeliness and reliability for application traffic. However, the performance of PR-SCTP can be affected by certain traffic characteristics and network scenarios. We previously proposed an NR-SACK based optimization for PR-SCTP. In this work, we extensively evaluate and analyze the performance of PR-SCTP with NR-SACKs using different network scenarios. Moreover, we compare the performance of our NR-SACK based PR-SCTP with existing transport protocols for syslog traffic. In the evaluation, we use real syslog traces from an operational syslog system. The results indicate that NR-SACK based PR-SCTP significantly improves the overall message transfer delay as compared to SCTP and TCP. 相似文献
35.
Jason S. Fish Sandrine Ricote Filip Lenrick L. Reine Wallenberg Tim C. Holgate Ryan O’Hayre Nikolaos Bonanos 《Journal of Materials Science》2013,48(18):6177-6185
A novel two-phase ceramic composite (cercer) material consisting of a solid solution of barium cerate and -zirconate doped with yttrium (BaCe0.2Zr0.7Y0.1O3?δ : BCZY27), together with niobium-doped strontium titanate (Sr0.95Ti0.9Nb0.1O3?δ : STN95), has been synthesized by solid-state reaction and sintered conventionally (CS) at 1350–1500 °C, as well as by spark plasma sintering (SPS) at 1300–1350 °C. CS samples were porous and exhibited high degrees of inter-phase reaction. Nickel oxide sintering aids did not improve CS sample density. In contrast, samples made by SPS were significantly denser (>95 %) and showed less reaction between phases. A pseudo-optimum SPS profile was developed, accounting for the effects of thermal expansion mismatch between BCZY27 and STN95. X-ray diffraction indicated secondary phases exist, but there was no indication of their presence at grain boundaries based on thorough study of these regions with high-resolution transmission electron microscopy and selective area electron diffraction. We thus suggest that these phases are present as independent grains in the bulk. It is believed these secondary phases inhibit electronic conductivity in the composite. 相似文献
36.
Semiconductor III-V nanowires are promising components of future electronic and optoelectronic devices, but they typically show a mixed wurtzite-zinc blende crystal structure. Here we show, theoretically and experimentally, that the crystal structure dominates the conductivity in such InP nanowires. Undoped devices show very low conductivities and mobilities. The zincblende segments are quantum wells orthogonal to the current path and our calculations indicate that an electron concentration of up to 4.6 × 10(18) cm(-3) can be trapped in these. The calculations also show that the room temperature conductivity is controlled by the longest zincblende segment, and that stochastic variations in this length lead to an order of magnitude variation in conductivity. The mobility shows an unexpected decrease for low doping levels, as well as an unusual temperature dependence that bear resemblance with polycrystalline semiconductors. 相似文献
37.
Filip Lenrick Martin Ek Knut Deppert Lars Samuelson L. Reine Wallenberg 《Nano Research》2014,7(8):1188-1194
Live observations of growing nanowires using in situ transmission electron microscopy (TEM) is becoming an increasingly important tool for understanding the dynamic processes occurring during nanowire growth. Here we present observations of growing InAs nanowires, which constitute the first reported in situ growth of a In-V compound in a transmission electron microscope. Real time observations of events taking place over longer growth lengths were possible due to the high growth rates of up to I nm/s that were achieved. Straight growth (mainly in 〈111〉B directions) was observed at uniform temperature and partial pressure while intentional fluctuations in these conditions caused the nanowires to form kinks and change growth direction. The mechanisms behind the kinking are discussed in detail. In situ observations of nanowire kinking has previously only been reported for nonpolar diamond structure type materials (such as Si), but here we present results for a polar zinc blende structure (InAs). In this study a closed cell with electron and X-ray transparent a-SiN windows was used in a conventional high resolution transmission electron microscope, enabling high resolution imaging and compositional analysis in between the growth periods. 相似文献
38.
V. Rao H. Ehsani I. B. Bhat M. Kestigian R. Starr M. H. Weiler M. B. Reine 《Journal of Electronic Materials》1995,24(5):437-443
We report arsenic doping of Hg1-xCdxTe (0.2 < x < 0.3) grown using metalorganic vapor phase epitaxy (MOVPE) by the direct alloy growth (DAG) technique. Tertiarybutylarsine
(TBAs) was used as a precursor for As doping. Several epilayers were grown at different Hg partial pressures and TBAs bubbler
temperatures in order to study the doping characteristics. The amount of As incorporated in the layer as well as the acceptor
concentration were found to be a strong function of the Hg pressure. Secondary ion mass spectrometric studies on heterostructures
showed that the compositional interdiffusion is less than the diffusion of As during growth. P-N junctions were grown using
TBAs for the first time and several of these layers were processed to fabricate photodiodes. A p-on-n grown junction photodiode
with a cutoff wavelength of 8.2 μm had an RoA value of 241 ohm-cm2 at 80K and is the highest reported value for p-on-n DAG-MOVPE devices. Methods to improve the device RoA of the grown junctions are also proposed. 相似文献
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