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91.
We present the second part of the investigation of the high sensitivity absorption spectrum of nitrous oxide by CW-Cavity Ring Down Spectroscopy near 1.5 μm. In a first paper [A.W. Liu, S. Kassi, P. Malara, D. Romanini, V.I. Perevalov, S.A. Tashkun, S.M. Hu, A. Campargue, J. Mol. Spectrosc. 244 (2007) 33-47] devoted to the 6000-6833 cm−1 region, more than 6000 line positions of five isotopologues (14N216O, 15N14N16O, 14N15N16O, 14N217O, and 14N218O), were rovibrationally assigned to a total of 68 bands. The achieved noise equivalent absorption (αmin ∼ 2 × 10−10 cm−1) allowed for the detection of lines with intensity weaker than 2 × 10−29 cm/molecule. In this contribution, the investigated region was extended down to 5905 cm−1 and additional recordings allowed accessing small spectral sections uncovered in our preceding recordings. A deeper analysis based on the predictions of the effective Hamiltonian model has allowed assigning a total of 3149 transitions and lowering the percentage of lines left unassigned from 51% to 28%. It led to the analysis of 35, 6, 7, and 6 bands for the 14N216O, 15N14N16O, 14N15N16O, and 14N218O isotopologues, respectively. Forty-two of these 54 bands are newly observed, while the rotational analysis of the twelve others is significantly extended and improved. Most of the bands were found unperturbed and their line positions could be reproduced within the experimental uncertainty (about 1 × 10−3 cm−1). The corresponding spectroscopic parameters are reported. Local rovibrational perturbations induced by either intrapolyad or interpolyad couplings were found to affect five hot bands of 14N216O. Their detailed analysis is presented. 相似文献
92.
It is well known under the name of ‘periodic homogenization’ that, under a centering condition of the drift, a periodic diffusion process on Rd converges, under diffusive rescaling, to a d-dimensional Brownian motion. Existing proofs of this result all rely on uniform ellipticity or hypoellipticity assumptions on the diffusion. In this paper, we considerably weaken these assumptions in order to allow for the diffusion coefficient to even vanish on an open set. As a consequence, it is no longer the case that the effective diffusivity matrix is necessarily non-degenerate. It turns out that, provided that some very weak regularity conditions are met, the range of the effective diffusivity matrix can be read off the shape of the support of the invariant measure for the periodic diffusion. In particular, this gives some easily verifiable conditions for the effective diffusivity matrix to be of full rank. We also discuss the application of our results to the homogenization of a class of elliptic and parabolic PDEs. 相似文献
93.
In this paper we continue the study of paired-domination in graphs introduced by Haynes and Slater (Networks 32 (1998), 199–206). A paired-dominating set of a graph G with no isolated vertex is a dominating set of vertices whose induced subgraph has a perfect matching. The paired-domination
number of G, denoted by γ
pr(G), is the minimum cardinality of a paired-dominating set of G. The graph G is paired-domination vertex critical if for every vertex v of G that is not adjacent to a vertex of degree one, γ
pr(G − v) < γ
pr(G). We characterize the connected graphs with minimum degree one that are paired-domination vertex critical and we obtain sharp
bounds on their maximum diameter. We provide an example which shows that the maximum diameter of a paired-domination vertex
critical graph is at least 3/2 (γ
pr(G) − 2). For γ
pr(G) ⩽ 8, we show that this lower bound is precisely the maximum diameter of a paired-domination vertex critical graph.
The first author was supported in part by the South African National Research Foundation and the University of KwaZulu-Natal,
the second author was supported by the Natural Sciences and Engineering Research Council of Canada. 相似文献
94.
We determine the quark distributions and structure functions for both unpolarized and polarized DIS of leptons on nucleons and nuclei. The scalar and vector mean fields in the nucleus modify the motions of the quarks inside the nucleons. By taking into account this medium modification, we are able to reproduce the experimental data on the unpolarized EMC effect, and to make predictions for the polarized EMC effect. We discuss examples of nuclei where the polarized EMC effect could be measured. We finally present an extension of our model to describe fragmentation functions. 相似文献
95.
Xuegong Tan 《Discrete Mathematics》2008,308(20):4786-4790
The k-dimensional folded Petersen graph, FPk, is an iterative Cartesian product on the simple Petersen graph. As an essential component of folded Petersen cube, folded Petersen graph has many important properties. In this paper, we prove that the 3k-wide diameter and 3k-fault diameter of k-dimensional folded Petersen graph is either 2k+1 or 2k+2. Furthermore, we show that FPk is interval monotone. 相似文献
96.
Anteroposterior diameter changes of the rib cage and abdomen were recorded during respiratory and speaking activities in four adult subjects, three men and one woman, all of whom had extensive dramatic training and experience and were earning their livelihood as professional actors. Data were charted to solve for lung volume, and volume displacements of the rib cage and abdomen. The more vigorous and louder monologue performances by the professional actor subjects differed from other speaking and reading activities in the following parameters of lung volume, separate volumes, relative volume contributions, and the frequent use of respiratory phase transitions. Novice actor subjects' monologue performances are compared to the monologue performances of the professional actor subjects. 相似文献
97.
98.
Purge-and-trap gas chromatography-mass spectrometry (PT-GC-MS) has become an accepted method for the analysis of trihalomethanes (THMs) in water. The purge-and-trap technique is based on an efficient transfer of volatile organic compounds from the liquid (contained in the purge chamber) to the gaseous phase by bubbling with an inert gas. The aim of this work was to study the purge system's efficiency by means of several consecutive purge cycles lasting 11 min each of the same liquid sample. The concentration range chosen of THMs was very wide [5-200 μg L−1]. The inert gas flow rate was 40 mL min−1, and experiments were performed at temperatures of 25, 35 and 50 °C. Bromoform (CHBr3), the least volatile compound, needed 19 cycles to be purged quantitatively at a concentration of 200 μg L−1 and only 7 cycles at 5 μg L−1 for a 25 mL sample at 25 °C. Chloroform (CHCl3), the most volatile compound, required 4 cycles to be fully extracted at 200 μg L−1 and 2 at 5 μg L−1. Finally, Novak's theoretical model, based on the distribution constant between gas and liquid phases, was used to correlate the THMs purging extraction data. 相似文献
99.
This paper deals with the study of different microporous ceramic membranes used as separators in electrochemical reactors to treat the activating solutions coming from the electroless plating of polymers. The main component of these solutions is Sn(IV) in HCl as diluting agent, then, the effect of the complex species formed between Sn4+ and Cl− ions on the electrical properties of the membranes has been studied. 相似文献
100.
双环网是计算机互连网络和通讯系统的一类重要拓扑结构,已广泛应用于计算机互连网络拓扑结构的设计中.利用L形瓦理论,结合中国剩余定理和二次同余方程的性质,给出了不同于参考文献中的任意k紧优双环网的无限族的构造方法,证明了对任意正整数k,若n(t)=3t2 At B,A=1,3,5,对于一定的B>(k 1)2,均存在正整数t,使得{G(n(t);s(t))}是k紧优双环网的无限族,而且这样的无限族有无穷多类.作为定理的应用,给出了多类新的k紧优双环网的无限族. 相似文献