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排序方式: 共有402条查询结果,搜索用时 15 毫秒
1.
通过耦合三维微波腔中光子和腔内钇铁石榴石单晶小球中的自旋波量子形成腔-自旋波量子的耦合系统,并通过精确调节系统参数在该实验系统中观测到各向异性奇异点.奇异点对应于非厄米系统中一种特殊状态,在奇异点处,耦合系统的本征值和本征矢均简并,并且往往伴随着非平庸的物理性质.以往大量研究主要集中在各向同性奇异点的范畴,它的特征是在系统参数空间中沿着不同参数坐标趋近该奇异点时具有相同的函数关系.在这篇文章中,主要介绍实验上在腔光子-自旋波量子耦合系统中通过调节系统的耦合强度和腔的耗散衰减系数两条趋近奇异点的路径而实现了各向异性奇异点,具体分别对应于在趋近奇异点时,本征值的虚部的变化与耦合强度和腔的衰减系数的变化会有线性和平方根不同的行为.各向异性奇异点的实现有助于基于腔光子-自旋波量子耦合系统的量子信息处理和精密探测器件的进一步研究. 相似文献
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Yan Xu 《Journal of Mathematical Analysis and Applications》2007,329(2):1343-1354
In this paper, we obtain some normality criteria for families of meromorphic functions that concern the exceptional functions of derivatives. 相似文献
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吴桂荣 《数学物理学报(A辑)》1998,18(1):116-120
该文对一般的随机变量序列及相当弱的系数条件研究了随机级数定义的整函数的奈望里纳特征函数,并证明了它是几乎必然无有限例外值的. 相似文献
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Development of a multicriteria assessment model for ranking biomass feedstock collection and transportation systems 总被引:1,自引:0,他引:1
Amit Kumar Shahab Sokhansanj Peter C. Flynn 《Applied biochemistry and biotechnology》2006,129(1-3):71-87
This study details multicriteria assessment methodology that integrates economic, social, environmental, and technical factors
in order to rank alternatives for biomass collection and transportation systems. Ranking of biomass collection systems is
based on cost of delivered biomass, quality of biomass supplied, emissions during collection, energy input to the chain operations,
and maturity of supply system technologies. The assessment methodology is used to evaluate alternatives for collecting 1.8×106 dry t/yr based on assumptions made on performance of various assemblies of biomass collection systems is based on cost of
delivered biomass, quality of biomass supplied, emissions during collection, energy input to the chain operations, and maturity
of supply system technologies. The assessment methodology is used to evaluate alternatives for collecting 1.8×106 dry t/yr based on assumptions made on performance of various assemblies of biomass collection systems. A proposed collection
option using loafer/stacker was shown to be the best option followed by ensiling and baling. Ranking of biomass transport
systems is based on cost of biomass transport, emissions during transport, traffic congestion, and maturity of different technologies.
At a capacity of 4×106 dry t/yr, rail transport was shown to be the best option, followed by truck transport and pipeline transport, respectively.
These rankings depend highly on assumed maturity of technologies and scale of utilization. These may change if technologies
such as loafing or ensiling (wet storage) methods are proved to be infeasible for large-scale collection systems. 相似文献
8.
A series of samples of increasing volume (from 0.001 to 4.0 cm3), containing the same constant concentration (40 g/l) of two simple compounds, ethylbenzoate and 4-tert.-butylphenol were injected on a Kromasil-C18 column with methanol-water (62:38. v/v) as the mobile phase. Complex band profiles were observed when the volume of the sample became large enough and strong band interference took place. The analysis of the fractions collected during the elution of the mixed band demonstrates that, for samples larger than 2 cm3, the band of 4-tert.-butylphenol is split into two separate bands, one eluted before and the other eluted after the band of ethylbenzoate. Such a phenomenon has never been observed yet in RPLC, under isocratic elution conditions. 相似文献
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The performance of a double sided silicon strip detector (DSSSD), which is used for the position and energy detection of heavy ions, is reported. The analysis shows that although the incomplete charge collection (ICC) and charge sharing (CS) effects of the DSSSD give rise to a loss of energy resolution, the position information is recorded without ambiguity. Representations of ICC/CS events in the energy spectra are shown and their origins are confirmed by correlation analysis of the spectra from both the junction side and ohmic side of the DSSSD. 相似文献