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111.
Bianca Haberl Jamie J. Molaison Joerg C. Neuefeind Luke L. Daemen Reinhard Boehler 《高压研究》2013,33(3):426-437
ABSTRACTA simple modified Bridgman design for large volume pressure anvils usable in the Paris-Edinburgh (PE) press has been demonstrated at Oak Ridge National Laboratory Spallation Neutron Source. The design shows advantages over the toroidal anvils typically used in the PE press, mainly rapid compression/decompression rates, complete absence of blow-outs upon drastic phase transitions, simplified cooling, high reliability, and relative low loads (~40 tons) corresponding to relatively high pressures (~20?GPa). It also shows advantages over existing large-volume diamond cells as sample volumes of ~2–3?mm3 can be easily and rapidly synthesized. The anvils thus allow sample sizes sufficient for in situ neutron diffraction as well as rapid synthesis of adequate amounts of new materials for ex situ analysis via total neutron scattering and neutron spectroscopy. 相似文献
112.
针对非晶硅锗电池本征层高锗含量时界面带隙失配以及高界面缺陷密度造成电池开路电压和填充因子下降的问题,通过在PI界面插入具有合适带隙的非晶硅缓冲层,不仅有效缓和了带隙失配,降低界面复合,同时也通过降低界面缺陷密度改善内建电场分布,从而提高了电池的收集效率. 进一步引入IN界面缓冲层以及对非晶硅锗本征层进行能带梯度设计,在仅采用Al背电极时,单结非晶硅锗电池转换效率达8.72%.
关键词:
非晶硅缓冲层
非晶硅锗薄膜太阳电池
带隙
界面 相似文献
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114.
A. T. Naveed M. Q. Huda K. F. Abd El-Rahman J. Hartung J. H. Evans-Freeman A. R. Peaker D. C. Houghton C. Jeynes W. P. Gillin 《Journal of luminescence》1998,80(1-4):381-386
Strained Si1−xGex/Si quantum wells have been doped with erbium by implantation. A comparison is made with strained Si1−xGex/Si quantum wells and relaxed Si1−xGex, with x between 10% and 25%, doped with erbium during MBE growth. The erbium concentration was between 1×1018 and 5×1018 cm−3 throughout the active regions. Transmission electron microscopy, X-ray diffraction, and photoluminescence studies indicate that good regrowth can been achieved after full amorphisation by implantation of the strained quantum wells. The erbium luminescence is more intense in the Si1−xGex/Si layers, but erbium-implanted samples containing Si1−xGex exhibit defect luminescence in the region of 0.9–1.0 eV. These defects are also present when Si1−xGex/Si quantum wells are implanted with an amorphising dose of silicon, and then regrown. They are attributed to small germanium-rich platelets, rather than to erbium-related defects. Electroluminescence is presented from a forward biased erbium-implanted Si0.87Ge0.13/Si structure at a drive current density of only 1.8 mA/cm2. 相似文献
115.
The reaction of bisgermavinylidene [(Me3SiN?PPh2)2C?Ge→Ge?C(PPh2?NSiMe3)2] ( 1 ) with AdNCO (Ad = Adamantyl) afforded the [2 + 2] cycloadditon product [(Me3SiN?PPh2)2CGeC(O) NAd] ( 2 ). Similar reaction of 1 with Ph3SiOH in tetrahydrofuran (THF) yielded the base‐stabilized germanium(II) triphenylsiloxide [H2C(PPh2?NSiMe3)2Ge(OSiPh3)2] ( 3 ). The results suggested that reactive germavinylidene may exist in solution and is capable of forming addition reaction products. The X‐ray structures of 2 and 3 were determined. Copyright © 2007 John Wiley & Sons, Ltd. 相似文献
116.
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119.
Yolla Kazzi Houssein Awada Marie‐Odile David Michel Nardin 《Surface and interface analysis : SIA》2007,39(8):691-697
Nanostructured multilayers constituted by alternate metallic (gold) and organic (alkyldithiol) layers, and grafted onto glass or silicon substrates are prepared and analysed. Such complex layers could be of interest as a new type of surfaces but also as localized dissipative zones particularly in the field of adhesion science. The formation and the structure of these model systems are examined using a number of techniques such as atomic force microscopy (AFM), wetting analysis (contact angles), X‐ray photoelectron spectroscopy (XPS) and conductivity measurements. It is shown that, in terms of electrical conductivity, gold layers exhibit a percolation transition from an insulating granular structure to a conductive worm‐like structure at a threshold thickness of about 5 nm. XPS (and wettability) analyses clearly indicate that the fractional coverage of the gold surface is about 30% with alkyldithiol and that these molecules are either grafted in a stand‐up position or in the form of a loop. Moreover, a partial electrical connection between two successive gold layers is observed, confirming that the confined organic layer of alkyldithiol between them is too loosely organized to play the role of an insulating barrier. Copyright © 2007 John Wiley & Sons, Ltd. 相似文献
120.
A. A. Andreev V. V. Konshin N. A. Vinokurov N. V. Komarov 《Russian Chemical Bulletin》2006,55(8):1430-1432
A straightforward synthesis of tetra-and trialkynylgermanes by reactions of compounds containing Ge-N or Ge-Cl bonds with
alk-1-ynes was proposed. Reactions of appropriate amino-or halogermanes with alk-1-ynes were effective only in the presence
of an equivalent amount of zinc dihalide.
Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 8, pp. 1377–1379, August, 2006. 相似文献