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1.
Wireless Personal Communications - In the present scenario, there is a boom in the demand of the users to achieve increased capacity, high data, low latency, and high-performance rates. 5G New...  相似文献   
2.
Some substituted coumarins have been synthesized by von-Pechmann condensation using SnCl2 · 2H2O (10 mol %) as catalyst in ethanolic medium. The reactions are simple, easy in handling and environmentally benign.  相似文献   
3.
Organic molecular scintillating crystals are noted for their good timing and particle discrimination process. Trans-stilbene is one such candidate noted for its good particle detection characteristics for the past five decades. Progressive strengthening of detection characteristics of trans-stilbene has been attempted by improving crystal perfection. A series of timing resolution studies have been carried out for the Bridgman grown trans-stilbene crystals under different experimental conditions. The results were compared with the previously reported values. Pulse shape discrimination process has been carried out for 241Am and 252Cf sources and good discrimination has been obtained for gamma-alpha and gamma-neutron sources from the grown organic phosphor crystal. Electronic Publication  相似文献   
4.
The single-particle excitation spectrum and the density of states (DOS) for a superconducting bilayer composite are calculated by solving the Bogoliubov equations. The bilayer consists of two different superconducting films in contact. The superconducting order parameters of the films 1 and 2 are assumed constant. For various film thicknesses the dependence of the DOS on the ratio 1/2 is shown. This dependence is most prominent for states with excitation energy less than 2.  相似文献   
5.
Poly(vinyl chloride) (PVC) membrane electrodes to determine monomer concentrations of tetradecyltrimethylammonium ion (TTA+) and hexadecylpyridinium ion (HPy+) based on neutral ion-pair carrier complexes of tetradecyltrimethylammonium dodecyl sulfate (TTA+-DS) and hexadecylpyridinium dodecyl sulfate (HPy+-DS), respectively, are reported here. The electrodes exhibit a Nernstian slope of 59 mV per decade for TTA+ and a sub-Nernstian slope of 34.5 mV per decade for HPy+ ions. The TTA+ ion-selective electrode (ISE) and the HPy+-ISE can determine the monomer units down to concentrations as low as 4.0×10−4M and 1.66×10−5 M, respectively. The effect of various additives, such as the anionic polyelectrolyte sodium dextran sulfate and macrocyclic β-cyclodextrin, on the surface activity exhibited by the cationic surfactants TTA+-DS and HPy+-DS, in the presence of background concentrations of NaCl was also examined with surfactant-selective sensors. The Gibbs free energy of micelle formation (ΔG m ) of both surfactants in the presence of various additives was calculated and found to be less favorable with respect to an increase in the amount of additives due to less availability of cationic surfactant monomer units. The ion-pair complexes TTA+-DS and HPy+-DS were found to behave as selective carrier compounds in PVC membranes in determining the concentration of monomer units of both TTA+ and HPy+, respectively. The proposed sensors worked well at a fairly acidic pH of 1–6.5 with response time of 60 s. The sensors responded well to the surfactant ions even in the presence of additives at lower concentration. The lifetime of the sensors is 3 mon.  相似文献   
6.
Different rubber formulations were designed using nitrile rubber and a mixed crosslinking system consisting of sulfur/accelerator and electron beam radiation. Based on the experimental results, an artificial neural network (ANN) was constructed to simulate the mechanical properties and volume fraction of rubber. The ANN could predict accurately the above properties for a series of nitrile rubber compounds. However, the number of training data played a key role in the ANN predictive quality. In addition, the more complex the nonlinear relation between input and output was, the larger was the number of training dataset required. The predicted results were further validated using another mathematical model. The constructed ANN was verified with a completely different styrene butadiene rubber system. The prediction was found to be extremely good. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 100: 2227–2237, 2006  相似文献   
7.
For complex reactions, the choice of reactor type is important for attaining optimum product yields. Strategies for specifying reactor types have beenIn this paper, product yield in a Van de Vusse reaction scheme has been studied for a wide range of the rate constants, in a reactor system consisting  相似文献   
8.
Castor oil was hydrogenated to evaluate the effect of agitation during hydrogenation. The turbine and propeller impellers were evaluated during hydrogenation of castor oil at various temperatures, pressures, and catalyst concentrations. The effect of impeller position in the agitator at definite oil depth was also evaluated. Hydrogenation of castor oil at 130°C, 2.0 kg/cm2 hydrogen gas pressure with 0.5% Ni catalyst for 6 h while using two turbine impellers fitted in an agitator, one close to the reactor bottom and another at a height just below the top oil layer, revolving at 350 rpm, resulted in a product of a iodine value of 4.1, hydroxyl value of 156.4, and slip point of 84°C.  相似文献   
9.
Pattern Analysis and Applications - The performance of graph-based learning techniques largely relies on the edges defined between the vertices of the graph. These edges that represent the affinity...  相似文献   
10.
Differencing and merging of architectural views   总被引:1,自引:0,他引:1  
Differencing and merging architectural views is an important activity in software engineering. However, existing approaches are still based on restrictive assumptions, such as requiring view elements to have unique identifiers or exactly matching types, which is often not the case in many application domains. We propose an approach based on structural information. We generalize a published polynomial-time tree-to-tree correction algorithm that detects inserts, renames and deletes, into a novel algorithm that additionally detects restricted moves. Our algorithm also supports forcing and preventing matches between view elements. We incorporate the algorithm into tools to compare and merge Component-and-Connector (C&C) architectural views. We provide an empirical evaluation of the algorithm. We illustrate the tools using extended examples, and use them to detect and reconcile interesting differences between real architectural views. This article is an expanded version of the following paper: Abi-Antoun, M., Aldrich, J., Nahas, N., Schmerl, B., and Garlan, D: 2006, ‘Differencing and Merging of Architectural Views’. In: Proceedings of the 21st IEEE International Conference on Automated Software Engineering, pp. 47–58.  相似文献   
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