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171.
172.
The purpose of this paper is twofold: We first present a sufficient condition for testing strictly generalized diagonally dominant matrices (i.e., H-matrices) and we claim that our criterion is superior to the existing ones. We then show that the proper subset of the H-matrices determined by the condition preserves the closure property under the Schur complement operation. 相似文献
173.
在苯类化合物的凯库勒结构的研究中引入了反强迫数和反凯库勒数.通过分析矩形和斜带模型苯类化合物的分子图的结构,证明了具有k行l列的矩形R[k,l]和斜带模型Z[k,l]的反凯库勒数是2,R[k,l]的反强迫数是l,Z[k,l]的反强迫数不超过[(l+1)/2],其中[x]表示不超过x的最大整数. 相似文献
174.
Haowen Huang Fang Liu Shaowen Huang Shishan Yuan Bo Liao Shoujun Yi Yunlong Zeng Paul K. Chu 《Analytica chimica acta》2012
A multiplexed bioanalytical assay is produced by incorporating two types of gold nanorods (GNRs). Besides retaining the desirable features of common GNRs LSPR sensors, this sensor is easy to fabricate and requires only a visible–NIR spectrometer for detection. This assay can simultaneously detect different acceptor–ligand pairs by choosing the proper GNRs possessing various LPWs in a wide detection wavelength range and can be developed into a high-throughput detection method. This bioanalytical assay allows easy detection of human serum specimens infected by S. japonicum and tuberculosis (TB) from human serum specimens (human serum/Tris–HCl buffer ratio = 1:104) without the need for sample pretreatment. The technique is very sensitive compared to other standard methods such as indirect hemagglutination assays (IHA) that require a serum concentration ratio of larger than 1:20 and enzyme-linked immunosorbent assays (ELISA) requiring a ratio larger than 1:100. This methodology can be readily extended to other immunoassays to realize wider diagnostic applications. 相似文献
175.
本文讨论Euler方法用于求解线性中立型随机延迟微分方程初值问题时数值解的稳定性,利用了一种不同于以往文献中的证明技巧,给出了Euler方法均方稳定的一个充分条件.文末的数值试验证实了本文所获理论结果的正确性. 相似文献
176.
A kind of compressible miscible displacement problems which include molecular diffusion and dispersion in porous media are investigated.A symmetric interior penalty discontinuous Galerkin (SIPG) method is applied to the coupled system of flow and transport.Using the induction hypotheses instead of the cut-off operator and the interpolation projection properties,a priori hp error estimates are presented.The error bounds in L2(H1) norm for concentration and in L∞(L2) norm for velocity are optimal in h and suboptimal in p with a loss of power 1/2. 相似文献
177.
One theoretical model is provided for the design of an on-chip all-optical analogue to electromagnetically induced transparency (EIT) in the two resonators system. The design parameters (the perimeter and the separation of the resonators), the side-coupling efficiency and the resonator loss of the system have been investigated. The analysis shows, properly designed, the system exhibits an EIT-like transmission spectrum: a narrow high quality factor resonant mode (the line-width is about 0.1 nm). 相似文献
178.
Z. Y. Tan L. L. Wang Y. C. Yang W. Z. Xiao 《The European Physical Journal B - Condensed Matter and Complex Systems》2012,85(4):138
First-principles calculations based on density functional theory (DFT) are performed to study the electronic structures and
magnetic properties of Rh-doped TiO2 crystals. The hybridization between Rh-4d and O-2p results in Rh becoming ferromagnetic with a magnetic moment of about 1.0 μ
B
per supercell. The Rh-doped TiO2 system exhibits half-metallic ferromagnetism based both DFT and DFT + U. The strong ferromagnetic couplings between local magnetic moments can be attributed to both the p-d hybridization and double-exchange mechanisms, as well as superexchange interaction. These results suggest an alternative
approach to achieve promising dilute magnetic semiconductors by doping non-magnetic transition metals in a TiO2 host. 相似文献
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