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81.
Francisco Javier González Javier Alda Jorge Simón James Ginn Glenn Boreman 《Infrared Physics & Technology》2009,52(1):48-51
In this paper the optical parameters at infrared frequencies of metallic thin films were obtained experimentally using a variable angle spectroscopic ellipsometer and used to simulate numerically the frequency response of antennas and antenna-coupled detectors at infrared frequencies (5–15 μm). The simulation results agree with previously published data and practical guidelines are presented for the design and fabrication of dipole and bowtie antennas at infrared frequencies. 相似文献
82.
It is important to calculate the Hausdorff dimension and the Hausdorff mesure respect to this dimension for some fractal sets. By using the usual method of Mass Distribution, we can only calculate the Hausdorff dimension. In this paper, we will construct an integral formula by using lower inverse s-density and then use it to calculate the Hausdorff measures for some fractional dimensional sets. 相似文献
83.
新颖的双通道输出高功率掺铒光纤宽带光源 总被引:1,自引:3,他引:1
在分析L波段放大自发辐射(ASE)谱产生原理的基础上,设计出一种新颖的双级结构掺铒光纤ASE宽带光源,该光源可在两个端口分别输出高功率的C波段和L波段的ASE谱.设计将C波段ASE谱注入到掺铒光纤中作为L波段ASE谱的二次抽运源,使得L波段ASE谱功率得到了有效提高.优化光源结构参量后从两个端口分别获得了12.97 dBm和12.81 dBm的C波段和L波段ASE宽带谱.将两个输出端口组合得到了功率为15.9 dBm,泵浦转换效率达到21.6%的C+L波段超宽带ASE光源. 相似文献
84.
Zhi-Yong Huang Zhi-Xia Zhuang Xiao-Ru Wang Frank S.C. Lee 《Analytica chimica acta》2004,508(2):239-245
Isotope dilution analysis method coupled with flow injection and inductively coupled plasma mass spectrometry (ID-FI-ICP-MS), enabled trace lead concentration in seawater to be determined and the high salt concentration in the matrix, such as Na+, Ca2+ and Mg2+, to be removed on-line. The operational parameters of the FI system including pH for the chelating reaction, concentration of 8-hydroxyquinoline-5-sulfonic acid (8-HQS), sample loading time and injection speed, washing time and speed, eluting acid concentration and eluting speed, and instrumental parameters for ICP-MS were optimized and selected. Accurate results could be achieved because the isotope ratios required can be precisely measured in the range of the eluting peak by means of ID-FI-ICP-MS. The 3σ detection limit was 0.204 ng ml−1. The trace lead concentration of seawater in south Xiamen, China was 0.988 ± 0.039 ng ml−1. The recoveries of spiked Pb standard in seawater and standard reference water (GBW 08607) were 97.9 and 101.0%, respectively, with a relative standard deviation of 0.98%. This method can be used to determine trace lead concentration in high salt matrix samples, and is especially useful when the eluting peaks do not have a Gaussian-distribution. 相似文献
85.
水杨酸甲酯清除羟基自由基活性的研究 总被引:1,自引:0,他引:1
利用脉冲辐解技术研究了水杨酸甲酯清除羟基自由基反应的瞬态吸收谱,测定了水杨酸甲酯与羟基自由基反应的表观速率常数。辅以常规检测方法,测定了水杨酸甲酯对羟基自由基的清除率。结果表明,水杨酸甲酯能快速有效清除羟基自由基。探讨了水杨酸甲酯清除羟基自由基的反应机制。 相似文献
86.
87.
88.
Let G be a simple graph with adjacency matrix A(G) and (G,x) the permanental polynomial of G. Let G × H denotes the Cartesian product of graphs G and H. Inspired by Kleins idea to compute the permanent of some matrices (Mol. Phy. 31 (3) (1976) 811–823), in this paper in terms of some orientation of graphs we study the permanental polynomial of a type of graphs. Here are some of our main results.1.If G is a bipartite graph containing no subgraph which is an even subdivision of K
2,3, then G has an orientation G
e such that (G,x) = det (xI-A(G
e
)), where A(G
e
) denotes the skew adjacency matrix of G
e.2.Let G be a 2-connected outerplanar bipartite graph with n vertices. Then there exists a 2-connected outerplanar bipartite graph
with 2n+2 vertices such that (G,x) is a factor of
.3.Let T be an arbitrary tree with n vertices. Then
, where
1
,
2
, ...,
n are the eigenvalues of T. 相似文献
89.
MA Jianhua LIN Weizhen DU Fuqiang HAN Zhenhui YAO Side & LIN Nianyun .College of Biology Engineering Jimei University Xiamen China .Laboratory of Nanobiomedicine & Laboratory of Radiation Chemistry Shanghai Institute of Applied Physics Chinese Acade Sciences Shanghai China 《中国科学B辑(英文版)》2005,48(4):292-296
Quinones including menadione are ubiquitous in nature. They play important roles in aerobic respira- tion and photosynthesis[1,2]. In addition, exogenous quinones are used as antibiotics and anticancer drugs. Their function is closely related to their red… 相似文献
90.
韩丕功 《数学物理学报(B辑英文版)》2005,25(3):533-544
This paper deals with the existence of solutions to the elliptic equation -△uμu/|x|2=λu |u|2*-2u f(x, u) in Ω, u = 0 on ( a)Ω, where Ω is a bounded domain in RN(N≥3),0∈Ω,2*=2N/N-2,λ>0,λ(a)σμ, σμ is the spectrum of the operator -△- μI/|x|2with zero Dirichlet boundary condition, 0 <μ<-μ,-μ=(N-2)2/4,f(x,u) is an asymmetric lower order perturbation of |u|2*-1 at infinity. Using the dual variational methods, the existence of nontrivial solutions is proved. 相似文献