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71.
Nandkishor N. Karade Jeevan M. Kondre Sumeet V. Gampawar Sandeep V. Shinde 《合成通讯》2013,43(13):2279-2287
A novel and direct method for the efficient synthesis of 2,5-disubstituted 1,3,4-oxadiazines from the reactions of [hydroxy(tosyloxy)iodo]benzene with substituted acetophenones, followed by the treatment with acid hydrazide and K2CO3, is reported. The methodology is also extended to the synthesis of 5-aryl-6H-1,3,4-thiadiazin-2-amine by using thiosemicarbazide under similar experimental conditions. 相似文献
72.
Radon data accumulated during 1992–1999 in the grid (30–34°N, 74–78°E) in N-W Himalaya have been anlaysed vis a vis seismic data recorded in the same area, supplied by Indian Meteorological Department (IMD) network. In general, there is a positive correlation between the total radon emission and the microseismicity in the area under investigation. The earthquake magnitude has moderate positive correlation with epicentral distance and low positive correlation with amplitude of radon precursory signal, whereas both show low negative correlation between them.
Empirical scaling relations are proposed using the best fit straight line from the log-linear graphs between magnitude of the events and log of the product of amplitude of radon anomaly and epicentral distance. The error between the recorded and calculated magnitude is also taken into account. The error range is higher at lower epicentral distances and magnitudes, showing that the local geology and tectonics have predominant influence on radon signals. 相似文献
73.
Spatial variations of radon and helium concentrations in soil-gas across the Shan-Chiao fault, Northern Taiwan 总被引:3,自引:0,他引:3
Spatial variability of gases like radon and helium in soil-gas can be used for seismic surveillance and for finding fault system. The present study is aimed at determining a possible connection between eventual radon/helium anomalies and active fault. Radon and helium concentrations in subsurface soil-gas have been monitored along the Shan-Chiao fault, Northern Taiwan. Twenty transverse profile surveys have been conducted across the fault, where 235 and 125 samples were collected for helium and radon analyses, respectively. The data analysis clearly reveals anomalous values of both radon and helium along the fault. To find the fault system, where the migration of gases is governed by advection, it is essential to identify the anomalies in both radon and helium together. The consistency of this pattern confirms that radon and helium together can act as a powerful tool for the detection and mapping of active fault zones. 相似文献
74.
Nandkishor N. Karade Girdharilal B. Tiwari Sandeep V. Shinde Sumeet V. Gampawar Jeevan M. Kondre 《Tetrahedron letters》2008,49(21):3441-3443
The solvent-free synthesis of 1-(p-toluenesulfonyloxy)-1,2-benziodoxol-3(1H)-one is reported from Dess-Martin periodinane and p-toluenesulfonic acid monohydrate using a grinding technique and is subsequently utilized for the α-tosyloxylation of a range of enolisable ketones. 相似文献
75.
Linking structural equation modeling to Bayesian networks: Decision support for customer retention in virtual communities 总被引:1,自引:1,他引:0
Bayesian networks are limited in differentiating between causal and spurious relationships among decision factors. Decision making without differentiating the two relationships cannot be effective. To overcome this limitation of Bayesian networks, this study proposes linking Bayesian networks to structural equation modeling (SEM), which has an advantage in testing causal relationships between factors. The capability of SEM in empirical validation combined with the prediction and diagnosis capabilities of Bayesian modeling facilitates effective decision making from identification of causal relationships to decision support. This study applies the proposed integrated approach to decision support for customer retention in a virtual community. The application results provide insights for practitioners on how to retain their customers. This research benefits Bayesian researchers by providing the application of modeling causal relationships at latent variable level, and helps SEM researchers in extending their models for managerial prediction and diagnosis. 相似文献
76.
Sumeet Kumar Stephen D. Heister Xianfan Xu James R. Salvador Gregory P. Meisner 《Journal of Electronic Materials》2013,42(6):944-955
A comprehensive numerical model has been proposed to model thermoelectric generators (TEGs) for automotive waste heat recovery. Details of the model and results from the analysis of General Motors’ prototype TEG were described in part I of the study. In part II of this study, parametric evaluations are considered to assess the influence of heat exchanger, geometry, and thermoelectric module configurations to achieve optimization of the baseline model. The computational tool is also adapted to model other topologies such as transverse and circular configurations (hexagonal and cylindrical) maintaining the same volume as the baseline TEG. Performance analysis of these different topologies and parameters is presented and compared with the baseline design. 相似文献
77.
Dua S Acharya UR Chowriappa P Sree SV 《IEEE transactions on information technology in biomedicine》2012,16(1):80-87
Texture features within images are actively pursued for accurate and efficient glaucoma classification. Energy distribution over wavelet subbands is applied to find these important texture features. In this paper, we investigate the discriminatory potential of wavelet features obtained from the daubechies (db3), symlets (sym3), and biorthogonal (bio3.3, bio3.5, and bio3.7) wavelet filters. We propose a novel technique to extract energy signatures obtained using 2-D discrete wavelet transform, and subject these signatures to different feature ranking and feature selection strategies. We have gauged the effectiveness of the resultant ranked and selected subsets of features using a support vector machine, sequential minimal optimization, random forest, and na?ve Bayes classification strategies. We observed an accuracy of around 93% using tenfold cross validations to demonstrate the effectiveness of these methods. 相似文献
78.
Sumeet Kumar Animesh K. Ojha Ranjan K. Singh 《Journal of Raman spectroscopy : JRS》2014,45(9):717-722
In the present report, bare CdO and CdO/MnO2 core/shell nanostructures of various cores and different shell sizes were synthesized using co‐precipitation method. The phase, size, shape and structural details of the bare CdO and CdO/MnO2 nanostructures were investigated by X‐ray diffraction, transmission electron microscopy (TEM), and Raman spectroscopy measurements. TEM micrographs confirm the formation of core/shell nanostructures. The presence of CdO (core) and MnO2 (shell) crystal phases was determined by analyzing the Raman data of bare CdO and CdO/MnO2 core/shell nanostructures. The Raman spectra of bare CdO nanostructures contain one broad intense convoluted envelop of three bands in the spectral range of 200–500 cm−1 and a weaker band located at ~940 cm−1. The intensity of these two Raman bands is decreased with the increase of shell size and disappeared completely for the shell size 5.3 ± 1 nm. Further, two new Raman bands appeared at ~451 and ~665 cm−1 for the shell size 1.3 ± 0.1 nm. These two Raman bands are assigned to the deformation of Mn–O–Mn and Mn–O stretching modes of MnO2. The intensity of these two Raman bands is enhanced with the increase of shell size and attains a maximum value for the shell size 5.3 ± 1 nm. The disappearance of characteristics Raman bands of CdO phase and the appearance of characteristics Raman bands corresponding to MnO2 phase for nanostructures of shell size 5.3 ± 1 nm authenticate the presence of CdO as core and MnO2 as shell in the core/shell nanostructures. Copyright © 2014 John Wiley & Sons, Ltd. 相似文献
79.
Rajeev Walia 《Advances in Mathematics》2009,222(5):1649-1686
In this paper we discuss the “Factorization phenomenon” which occurs when a representation of a Lie algebra is restricted to a subalgebra, and the result factors into a tensor product of smaller representations of the subalgebra. We analyze this phenomenon for symmetrizable Kac-Moody algebras (including finite-dimensional, semi-simple Lie algebras). We present a few factorization results for a general embedding of a symmetrizable Kac-Moody algebra into another and provide an algebraic explanation for such a phenomenon using Spin construction. We also give some application of these results for semi-simple, finite-dimensional Lie algebras.We extend the notion of Spin functor from finite-dimensional to symmetrizable Kac-Moody algebras, which requires a very delicate treatment. We introduce a certain category of orthogonal g-representations for which, surprisingly, the Spin functor gives a g-representation in Bernstein-Gelfand-Gelfand category O. Also, for an integrable representation, Spin produces an integrable representation. We give the formula for the character of Spin representation for the above category and work out the factorization results for an embedding of a finite-dimensional, semi-simple Lie algebra into its untwisted affine Lie algebra. Finally, we discuss the classification of those representations for which Spin is irreducible. 相似文献
80.
General and Facile Route to Isomerically Pure Tricyclic Peptides Based on Templated Tandem CLIPS/CuAAC Cyclizations
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Gaston J. J. Richelle Sumeet Ori Prof. Dr. Henk Hiemstra Prof. Dr. Jan H. van Maarseveen Prof. Dr. Peter Timmerman 《Angewandte Chemie (International ed. in English)》2018,57(2):501-505
We report a one‐pot ligation/cyclization technology for the rapid and clean conversion of linear peptides into tricyclic peptides that is based on using tetravalent scaffolds containing two benzyl bromide and two alkyne moieties. These react via CLIPS/CuAAC reactions with cysteines and azides in the peptide. Flexibility in the scaffolds is key to the formation of isomerically pure products as the flexible scaffolds T4 1 and T4 2 mostly promote the formation of single isomeric tricycles while the rigid scaffolds T4 3 and T4 4 do not yield clean products. There seems to be no limitation to the number and types of amino acids present as 18 canonical amino acids were successfully implemented. We also observed that azides at the peptide termini and cysteine residues in the center gave better results than compounds with the functional groups placed the other way round. 相似文献