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1.
This paper presents a part of the culmination of the collective efforts in developing a cohesive and consolidated enunciation of the spectroscopic parameters and their relationship to effective molecular Hamiltonians for diatomic formalism, linear four-atomic formalism and quasi-linearity, Watson Hamiltonian and the complexities in symmetric and asymmetric top spectral structures. All these considered together present a beautiful and consistent picture of molecular spectroscopy. In this paper we deal with the diatomic formalism. This paper forms our tribute to Professor K. Narahari Rao and in the second part of the paper we convoy our gratitude to him with a summary of his more than half century of work and an obituary. We will deal with other forms of molecular species which will be connected to optical pumping and/or interstellar space.  相似文献   
2.
The effect of a pseudo Aharonov-Bohm (AB) magnetic field generated by a disclination on a two-dimensional electron gas in graphene is addressed in the continuum limit within the geometric approach. The influence of the coupling between the spinor fields and the singular conical curvature is investigated, which shows that singularities have pronounced impact in the Hall conductivity. Moreover, the degeneracy related to the Dirac valleys is broken for negative values of the angular momentum quantum numbers, l, includingl ≡ 0. In this case, a Hall plateau develops at the null filling factor. Obtaining the Hall conductivity by summing over the positive and the negative l's, the null Landau level is recovered and the plateau at the null filling factor disappears. In any case, the standard plateaus, which are seen in a flat graphene are not obtained with these curvature and singular effects.  相似文献   
3.
《Analytical letters》2012,45(13):1063-1071
Abstract

A rapid, specific and sensitive reversed-phase liquid chromatographic (LC) assay for the quantitative determination of indomethacin in serum without extraction was developed. Chromatographic separation using flunixin meglumine as the internal standard was achieved on octadecylsilane-coated particles with a mobile phase of 0.15 M acetate buffer pH 3.0 (50% v/v), acetonitrile (30% v/v) and methanol (20% v/v). The recovery of indomethacin from serum samples in the concentration range of 0.1-25 μg/ml was 95.5 ± 5.8% and as little as 100 ng/ml of indomethacin in serum samples can be quantitated by this procedure. A serum level versus time profile of dog with intravenously administered indomethacin demonstrated the applicability of the assay.  相似文献   
4.
《Analytical letters》2012,45(12):1239-1248
Abstract

Reference electrodes limiting interfering effects of conventional reference electrodes on the measurement involving ion-selective electrodes have been developed. They are constructed of a plastic body with porous plug or sleeve junction. Solid state, low impedance, ion-selective electrodes (cupric, cadmium, fluoride) in the equilibrium of corresponding ion solution are used as the half-cells. The absence of interfering ions in the electrolyte allows the determination of the ion of interest at extremely low levels without interference. The electrodes have good reproducibility and stable intercomparison potentials of ± 0.2 mV. The performance of the electrodes has been tested for the measurement of sub-ppm halide levels. Data on stability, reproducibility, effects of temperature, ionic strengthand pH is presented and compared to that of conventional reference electrodes.  相似文献   
5.
《Analytical letters》2012,45(7):607-615
Abstract

A simple and sensitive sample clean up procedure and a reverse phase high performance liquid chromatographic assay for tiazofurin in dog plasma has been developed.

Thymidine was used as the internal standard and the elution solvent was 0.16 M acetic acid. The retention times of tiazofurin and thymidine at an elution rate of 2.0 ml/minute were 8.7 minutes and 16 minutes respectively. The assay sensitivity was 1.0 μG/ml. The within run coefficient of variation of 2.0 μG/ml and 20 μG/ml plasma samples were ±7.49% and ±3.37% respectively and the between run coefficient of variation of 2.0 μG/ml and 20.0 μG/ml plasma samples were ±10.46% and ±5.92% respectively.  相似文献   
6.
In this paper, a Model of the Hamiltonian function is reviewed for the slightly asymmetric class of molecules, which is the most successful so far, according to our present knowledge. This model does not have the redundancy problem suffered by previous models. The observed frequencies are calculated to within experimental accuracy. In our subsequent papers we will show the application of this model for the prediction and quantum number assignments of optically pumped far infrared lasers and thereby increasing the possibility of new lines in the region of the spectrum which severely lacks enough monochromatic sources. We will also show that this model is capable of calculating even MMW transitions for the second excited state of methanol. All the previous models consider transitions up to the first excited torsional state.  相似文献   
7.
In this paper the Backward Wave Oscillator (BWO) based spectroscopy technique and its application to molecular spectroscopy especially to diatomic molecules have been discussed. This is a new and electronically controlled technique with enormous capabilities most of which are yet to be exploited. This paper also presents a part of the culmination of the collective efforts in developing a cohesive and consolidated enunciation of the spectroscopic parameters and their relationship to effective molecular Hamiltonians for diatomic formalism, linear four- atomic formalism & quasi-linearity, Watson Hamiltonian and the complexities in symmetric and asymmetric top spectral structures and its relationship to optical pumping and / or interstellar space. All these considered together present a beautiful and consistent picture of molecular spectroscopy and THz Electromagnetic sources.  相似文献   
8.
In the literature several authors describe methods to construct simplified models of networks. These methods are motivated by the need to gain insight into the main properties of medium sized or large networks. The present paper contributes to this research by setting focus on weighted networks, the geographical component of networks and introducing a class of functions to model how the weights propagate from one level of abstraction to the next. Hierarchies of network models can be constructed from reordering of the adjacency matrix of the network; this is how “hypernodes” are derived in the present paper. The hypernode algorithm is explored and it is shown how it can be formulated to handle weighted networks. Weighted networks enable handling the uncertainty or the strength of the components which make up the network. The hypernode algorithm can be run in an iterative manner so that a hierarchy of simplified models of the network can be derived. Some case studies demonstrate the hypernode algorithm. In the first case the algorithm is compared with a similar implementation described in the literature. In the second case an airline dataset is analysed. This study shows that when networks are embedded in the geographical space hypernodes may relate to clusters in the spatial domain. The selection of the visual variables to illustrate the strength of the edges and nodes in a weighted network is discussed.  相似文献   
9.
A field study has been carried out in urban Assiut city, Egypt. The goals of this study are: (1) to carry out measurements to evaluate road traffic noise levels, (2) to determine if these levels exceeds permissible levels, (3) to examine people’s attitudes towards road traffic noise, (4) to ascertain the relationship between road traffic noise levels and degree of annoyance. The measurements indicate that traffic noise noise levels are higher than those set by Egyptian noise standards and policy to protect public health and welfare in residential areas: equivalent continuous A - weighted sound pressure levels (LA eq) = 80 dB and higher were recorded, while maximum permissible level is 65 dB. There is a strong relationship between road traffic noise levels and percentage of highly annoyed respondents. Higher road traffic noise levels mean that the percentage of respondents who feel highly annoyed is also increased.  相似文献   
10.
A method based on matrix solid-phase dispersion (MSPD) has been developed for the determination of 16 organochlorine pesticides (OCs) in sludge from municipal sewage plants. Samples of lyophilized sludge were blended with alumina, placed in small columns and OCs extracted with dichloromethane assisted by sonication. Purification of the extracts was accomplished by solid-phase extraction on C18 columns and OCs were eluted with acetonitrile. Analyses were performed by gas chromatography with electron impact mass spectrometric detection in the selected ion monitoring mode (GC–MS-SIM) using deuterated OCs as internal standards. The limits of detection were between 0.03 ng/g for 4,4′-DDE and 0.7 ng/g for endrin aldehyde.

Levels of OCs were determined in sewage sludge collected from 19 water treatment plants located in the province of Madrid (Spain). In all of the analyzed samples, aldrin was the compound most often found with a mean concentration of 76 ng/g. Endosulfan-I, -BHC, 4,4′-DDE and 4,4′-DDT were also present at high concentrations, with average values ranging from 32.3 to 74.3 ng/g. OCs were detected in all of the samples, with a total concentration ranging from 52 to 528 ng/g dry weight.  相似文献   

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