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1.
Corrosion in wet lime/limestone systems used for flue gas desulfurization in thermal power plants is of great concern. The frequent variations in acidity and in chloride and fluoride ion concentrations experienced by such systems pose a serious threat to the materials of construction. Currently used materials mostly type 316L stainless steel often fail to meet their life expectancy. The present study evaluates the performance of advanced Ni- Cr- Mo alloys 59 and C- 276 in a simulated sulfur dioxide scrubber environment. Accelerated tests showed that high Ni- Cr- Mo alloys have little tendency to leach metal ions such as chromium, nickel, and molybdenum at different impressed potentials. Scanning electron microscopy was used to examine the morphology of pitting attack.  相似文献   
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Recent advancements in cloud computing (CC) technologies signified that several distinct web services are presently developed and exist at the cloud data centre. Currently, web service composition gains maximum attention among researchers due to its significance in real-time applications. Quality of Service (QoS) aware service composition concerned regarding the election of candidate services with the maximization of the whole QoS. But these models have failed to handle the uncertainties of QoS. The resulting QoS of composite service identified by the clients become unstable and subject to risks of failing composition by end-users. On the other hand, trip planning is an essential technique in supporting digital map services. It aims to determine a set of location based services (LBS) which cover all client intended activities quantified in the query. But the available web service composition solutions do not consider the complicated spatio-temporal features. For resolving this issue, this study develops a new hybridization of the firefly optimization algorithm with fuzzy logic based web service composition model (F3L-WSCM) in a cloud environment for location awareness. The presented F3L-WSCM model involves a discovery module which enables the client to provide a query related to trip planning such as flight booking, hotels, car rentals, etc. At the next stage, the firefly algorithm is applied to generate composition plans to minimize the number of composition plans. Followed by, the fuzzy subtractive clustering (FSC) will select the best composition plan from the available composite plans. Besides, the presented F3L-WSCM model involves four input QoS parameters namely service cost, service availability, service response time, and user rating. An extensive experimental analysis takes place on CloudSim tool and exhibit the superior performance of the presented F3L-WSCM model in terms of accuracy, execution time, and efficiency.  相似文献   
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We present our studies of the low-frequency excess electrical noise in YBa2Cu3O7- thin films in the normal state. We have studied films with varying microstructure deposited on different substrates. The frequency dependence and bias current dependence of the noise power spectral density agree with the behavior expected for noise due to conductance fluctuations. Comparison between films on different substrates shows that the presence of defects such as grain boundaries in the film correlate with significantly enhanced noise levels. The noise levels in our good-quality epitaxial films are several orders of magnitude lower than the anomalously large noise magnitudes reported for YBa2Cu3O7- in most of the earlier studies.  相似文献   
4.
This study is novel to report the utilization of molasses for the production of polyhydroxy propionate-co-hydroxy dodecanoate-co-hydroxy octadecanoate from Pseudomonas sp. LDC-5 as prospective biomaterial. Thermal analysis revealed its potential for thermal permanence and melt processing. 3T3 fibroblasts were cultured on these different scaffolds and their proliferation was compared. Giemsa and acridine orange/ethidium bromide staining revealed that there was no distinct change in morphology. Polyhydroxyalkanoate:poly ethylene glycol blend was found to be the most promising for extracellular matrix secretion, a key thrust function of 3D culture. Lactate dehydrogenase assay indicated the membrane integrity. DNA fragmentation analysis showed that the scaffold did not damage DNA. Thus the prepared scaffold can serve as a promising biomaterial.  相似文献   
5.
The present article discusses the experimental results on cooling characteristics of a stationary hot steel plate by spray impingement. The experimental setup consisted of an electrically heated flat stationary steel plate of dimension 120 mm × 120 mm × 4 mm, spray setup, water supply, and air supply unit. The effects of various controlling parameters such as air-water pressures, water flow rate, nozzle tip to target distance and impingement density were determined and analyzed. The cooling rates were computed from the time-dependent temperature history and used to analyze the parametric effects. The results obtained in the study confirmed the higher efficiency of the spray cooling system and the cooling strategy was found advantageous over the conventional cooling methods available in the open literature.  相似文献   
6.
Novel near white light emitting Y2CaZnO5 (YCZ) nanocrystalline powders doped with Dy3+ ions were synthesized via the citrate gel combustion method. The structure of the compound is found to be triclinic with a particle size in the range of 20–30 nm. Luminescence properties have been characterized using photoluminescence (PL), excitation spectra and decay time measurements. The PL spectra have shown a broad blue band due to 4F9/26H15/2 transition and sharp yellow band corresponding to 4F9/26H13/2 transition of Dy3+ ions. From the concentration dependent PL studies, the optimum concentration of Dy3+ ions in YCZ is found to be 1.0 mol%, where intense near white light emission was observed. The Dy3+:YCZ nanophosphor has shown relatively better white color properties than the reported Dy3+:Y2O3 nanophosphor. The yellow to blue intensity ratios, CIE chromaticity coordinates and correlated color temperature studies have shown the possibility of using this compound for white light emission.  相似文献   
7.
This work explores the use of Real-parameter Genetic Algorithm and analyses its performance in the steam condenser (or Circulating Water System) optimization study of a 500 MW fast breeder nuclear reactor. Choice of optimum design parameters for condenser for a power plant from among a large number of technically viable combination is a complex task. This is primarily due to the conflicting nature of the economic implications of the different system parameters for maximizing the capitalized profit. In order to find the optimum design parameters a Real-parameter Genetic Algorithm model is developed and applied. The results obtained are validated with the reference study results.  相似文献   
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Summary Polyestermaleamides have been synthesized from N,N-bisisomaleimide, p-aminophenol, iso-and tere-phthaloyl chlorides. Through ring-opening addition reaction, a bisphenolamide was first formed; it was then polycondensed with acid chlorides to produce Polyestermaleamides, with an ordered sequence. The polymers were fully characterized by elemental analysis, infrared and electronic spectra, solubility in various solvents as well as inherent viscosity measurements. Thermal behaviour of the polymers were determined by thermogravimetric analysis in nitrogen atmosphere.  相似文献   
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