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991.
Prediction of air pollution impacts of a proposed fossil fuel-based power plant has been made using meteorological data, information on stack characteristics and emission rate, baseline air quality and validated model condition. It is observed that under normal operation, the emission rate of SO 2 and NO 2 is significant, while under a worst case scenario, the SPM emission rate is significant. It has been predicted that 24-hr average SO 2 , NO 2 and SPM concentrations due to proposed plant in normal operation would be around 38 w g/m 3 , 40 w g/m 3 and less than 1 w g/m 3 , respectively, beyond the site boundary. The total 24-hr average SPM concentration under the worst case beyond site boundary would be below the national air quality standard for SPM in a mixed industrial area. Therefore, the impact of proposed power plant on local air quality would be acceptable. However, the implementation of a green belt comprising various tree spacies which will act as dust attenuators around the site boundary alongwith efficient control measures at source would efficiently mitigate and minimised pollution impacts from the proposed power plant.  相似文献   
992.
In the present work, the plasticity of Zr64.2Cu11.2 Ni14.6Al10 bulk metallic glass was enhanced through prior compression treatment. A considerably large compressive plastic deformation (over 6.5%) was achieved by pressing Zr64.2Cu11.2 Ni14.6Al10 bulk metallic glass laterally in specially designed tool steel die before compression test. Numerical analysis was also carried out to investigate the stress distribution under same mechanical conditions. It was revealed that the lateral pressing induced structural heterogeneity and high stress gradients facilitate large plastic strains through the generation of dense multiple shear band network.  相似文献   
993.
The purpose of this study is to analyze comparatively the performance of nine thermal power plants under control governmental bodies in Turkey, from energetic and exergetic viewpoint. The considered power plants are mostly conventional reheat steam power plant fed by low quality coal. Firstly, thermodynamic models of the plants are developed based on first and second law of thermodynamics. Secondly, some energetic simulation results of the developed models are compared with the design values of the power plants in order to demonstrate the reliability. Thirdly, design point performance analyses based on energetic and exergetic performance criteria such as thermal efficiency, exergy efficiency, exergy loss, exergetic performance coefficient are performed for all considered plants in order to make comprehensive evaluations. Finally, by means of these analyses, the main sources of thermodynamic inefficiencies as well as reasonable comparison of each plant to others are identified and discussed. As a result, the outcomes of this study can provide a basis used for plant performance improvement for the considered coal-fired thermal power plants.  相似文献   
994.
Raman spectroscopy and the principal component analysis (PCA) were successfully applied to differentiate the origin of the meat and meat products based on their extracted fat samples in the present study. A total of 132 extracted fat samples that were obtained from different meat species (cattle, sheep, pig, fish, poultry, goat and buffalo) and their salami products were examined based on their Raman measurements. Then, the collected Raman data were analyzed with a four-stage PCA method. Seven meat species and their salami products were successfully differentiated from each other according to their origin. The results of this study showed that the Raman spectroscopy with a chemometric method can be used to detect the origin of the meat species in a very short analysis time (30 s) after fat extraction, without requiring complicated chromatographic, immunologic or genetic methods and instruments as well as trained personnel.  相似文献   
995.
Multidimensional sensors, such as digital camera sensors in the visual sensor networks VSNs generate a huge amount of information compared with the scalar sensors in the wireless sensor networks WSNs. Processing and transmitting such data from low power sensor nodes is a challenging issue through their limited computational and restricted bandwidth requirements in a hardware constrained environment. Source coding can be used to reduce the size of vision data collected by the sensor nodes before sending it to its destination. With image compression, a more efficient method of processing and transmission can be obtained by removing the redundant information from the captured image raw data. In this paper, a survey of the main types of the conventional state of the art image compression standards such as JPEG and JPEG2000 is provided. A literature review of their advantages and shortcomings of the application of these algorithms in the VSN hardware environment is specified. Moreover, the main factors influencing the design of compression algorithms in the context of VSN are presented. The selected compression algorithm may have some hardware-oriented properties such as; simplicity in coding, low memory need, low computational load, and high-compression rate. In this survey paper, an energy efficient hardware based image compression is highly requested to counter the severe hardware constraints in the WSNs.  相似文献   
996.
Hasan  Syed  Breunig  Robert 《Scientometrics》2021,126(9):7583-7608
Scientometrics - We examine the relationship between article length and citation counts. Focusing on articles published between 2010 and 2014 in the top five economics journals and their citation...  相似文献   
997.
The objective of solid-liquid separation in thickeners in coal preparation plants is to obtain both a clear supernatant liquid with a low turbidity for reuse and a dense slurry. It is important for the smooth operation of the plant to produce good-quality recirculation water. In this study, settling characteristics of coal tailings (d80=70 μm) taken from the thickener feed of Derekoy Coal Preparation Plant (Manisa, Turkey) were investigated with the use of anionic polymers. In the tests we determined the effects of the process parameters including polymer type, polymer dosage, temperature, suspension pH, and pulp density on the flocculation of the fine tailings of the coal preparation operation. Minefloc anionic polymer showed a better flocculation performance in comparison with other polymers. An optimum settling rate of 300 mm/min was reached at a dosage of 30 g/t-solids, a pulp density of 5%, pH 7.9, and temperature 25 °C using Minefloc polymer.  相似文献   
998.
The rate of breakage of drops and bubbles (fluid particles) in stirred systems is of great consequence on mass,heat, and momentum transport phenomena. Therefore, over the years, the topic has gained a considerable attention fromthe researchers to study and characterize this phenomenon. In present work, the experimental studies of breakage phenomenon in a stirred tank in the last four decadeswere reviewed. The reviewhighlighted the investigated experimental conditions and the major findings concerning the breakagemechanismand the effect of operating conditions. The discrepancy and contradictions of the outcomes of those studies were specified and discussed. Experimental observations and conclusions concerning the breakage characterization parameters,such as deformation, breakage probability, breakage time, and breakage location were presented and commented on. Possible future refinements and prospective were recommended. The review indicated that there are clear discrepancies and contradictions between previous studies regarding the effect of some operating parameters and the values of breakage time, breakage probability, number of daughter particles, and breakage location relative to the impeller. In addition, there are still many scientific gaps that need to be studied and characterized in future by overcoming specific experimental difficulties and uncertainties.  相似文献   
999.
Functional near-infrared spectroscopy (fNIR) is a neroimaging modality that enables continuous, noninvasive, and portable monitoring of changes in blood oxygenation and blood volume related to human brain function. Over the last decade, studies in the laboratory have established that fNIR spectroscopy provides a veridical measure of oxygenation and blood flow in the brain. Our recent findings indicate that fNIR can effectively monitor cognitive tasks such as attention, working memory, target categorization, and problem solving. These experimental outcomes compare favorably with functional magnetic resonance imaging (fMRI) studies, and in particular, with the blood oxygenation level dependent signal. Since fNIR can be implemented in the form of a wearable and minimally intrusive device, it has the capacity to monitor brain activity under real life conditions and in everyday environments. Moreover, the fNIR system is amenable to integration with other established physiological and neurobehavioral measures, including electroencephalogram, eye tracking, pupil reflex, heart rate variability, respiration, and electrodermal activity.  相似文献   
1000.
A tubular solid oxide fuel cell (TSOFC) module fed by methane is modelled and analyzed thermodynamically from the exergy point of view in this paper. The model of TSOFC module consists of mixer, pre-reformer, internal reforming fuel cell group, afterburner and internal pre-heater components. The model of the components forming module is given based on mass, energy and exergy balance equations. The developed thermodynamic model is simulated, and the obtained performance characteristics are compared and validated with the experimental data taken from the literature concerning TSOFC module. For exergetic performance analysis, the effects of operating variables such as current density, pressure, and fuel utilization factor on exergetic performances (module exergy efficiency, module exergetic performance coefficient, module exergy output and total exergy destruction rate, and components' exergy efficiencies, exergy destruction rates) are investigated. From the analysis, it is determined that the biggest exergy loss stems from exhaust gasses. Other important sources of exergy destruction involve fuel cell group and afterburner. Consequently, the developed thermodynamic model is expected to provide not only a convenient tool to determine the module exergetic performances and component irreversibility but also an appropriate basis to design complex hybrid power generation plants.  相似文献   
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