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Emission Control (emission + control)
Selected AbstractsRare-Earth Spontaneous Emission Control in Three-Dimensional Lithium Niobate Photonic CrystalsADVANCED MATERIALS, Issue 34 2009Airán Ródenas Spontaneous emission inhibition of erbium ions at 1.5,µm wavelength is obtained by tailoring direct femtosecond-laser-written 3D photonic structures inside lithium niobate laser crystals. This technique allows for engineering of the structure symmetry and filling fraction by spatially inscribing laser-induced amorphous voxels inside the crystalline sample. [source] Spontaneous Emission Control in Micropillar Cavities Containing a Fluorescent Molecular Dye,ADVANCED MATERIALS, Issue 6 2006M. Adawi The fabrication of micropillar microcavities containing a fluorescent organic dye is reported. Scanning near-field optical microscopy of the luminescence from such structures (see figure and cover) confirms that a significant increase in radiative rate occurs as a result of the reduced optical-mode volume. Such structures may eventually permit efficient single-photon light sources operating at room temperature to be developed for quantum-cryptography and quantum-computing applications. [source] Synthesis and Characterization of Silver Hollandite and Its Application in Emission Control.CHEMINFORM, Issue 45 2005Liyu Li Abstract For Abstract see ChemInform Abstract in Full Text. [source] Blue Luminescence of ZnO Nanoparticles Based on Non-Equilibrium Processes: Defect Origins and Emission ControlsADVANCED FUNCTIONAL MATERIALS, Issue 4 2010Haibo Zeng Abstract High concentrations of defects are introduced into nanoscale ZnO through non-equilibrium processes and resultant blue emissions are comprehensively analyzed, focusing on defect origins and broad controls. Some ZnO nanoparticles exhibit very strong blue emissions, the intensity of which first increase and then decrease with annealing. These visible emissions exhibit strong and interesting excitation dependences: 1) the optimal excitation energy for blue emissions is near the bandgap energy, but the effective excitation can obviously be lower, even 420,nm (2.95,eV,<,Eg,=,3.26,eV); in contrast, green emissions can be excited only by energies larger than the bandgap energy; and, 2) there are several fixed emitting wavelengths at 415, 440, 455 and 488,nm in the blue wave band, which exhibit considerable stability in different excitation and annealing conditions. Mechanisms for blue emissions from ZnO are proposed with interstitial-zinc-related defect levels as initial states. EPR spectra reveal the predominance of interstitial zinc in as-prepared samples, and the evolutions of coexisting interstitial zinc and oxygen vacancies with annealing. Furthermore, good controllability of visible emissions is achieved, including the co-emission of blue and green emissions and peak adjustment from blue to yellow. [source] Fuzzy torque distribution control for a parallel hybrid vehicleEXPERT SYSTEMS, Issue 1 2002Jong-Seob Won A fuzzy torque distribution controller for energy management (and emission control) of a parallel hybrid electric vehicle is proposed. The proposed controller is implemented in terms of a hierarchical architecture which incorporates the mode of operation of the vehicle as well as empirical knowledge of energy flow in each mode. Moreover, the rule set for each mode of operation of the vehicle is designed in view of an overall energy management strategy that ranges from maximal emphasis on battery charge sustenance to complete reliance on the electrical power source. The proposed control system is evaluated via computational simulations under the FTP75 urban drive cycle. Simulation results reveal that the proposed fuzzy torque distribution strategy is effective over the entire operating range of the vehicle in terms of performance, fuel economy and emissions. [source] New Design of a Ceramic Filter for Diesel Emission Control ApplicationsINTERNATIONAL JOURNAL OF APPLIED CERAMIC TECHNOLOGY, Issue 6 2005Aleksander J. Pyzik Diesel particulate filters (DPF) made from an advanced ceramic material (ACM) based on mullite have demonstrated high filtration efficiency, low-pressure drop, high-temperature handling capability, and excellent mechanical integrity at a porosity of 60% or higher. Due to the ability to control microstructure, total porosity, and particle size distribution, Dow's acicular mullite can be tailored to meet requirements for deep bed filtration and fine particles emission control. In addition, the ACM DPF is suitable for catalyzed applications and it can retain its performance with a broad range of catalysts and over a wide range of catalyst loadings. This study describes a material selected for a DPF design that meets current diesel particulate emission control requirements as well as a four-way NOx control system. [source] Power generation expansion planning with emission control: a nonlinear model and a GA-based heuristic approachINTERNATIONAL JOURNAL OF ENERGY RESEARCH, Issue 2 2006Jiraporn Sirikum Abstract This paper presents an application of genetic algorithms (GA) for solving the long-term power generation expansion planning (PGEP) problem, a highly constrained nonlinear discrete optimization problem. The problem is formulated into a mixed integer nonlinear programming (MINLP) program that determines the most economical investment plan for additional thermal power generating units over a planning horizon, subject to the requirements of power demands, power capacities, loss of load probability (LOLP) levels, locations, and environmental limitations. Computational results show that the GA-based heuristic method can solve the PGEP problem effectively and more efficiently at a significant saving in runtime, when compared with a commercial optimization package. Copyright © 2005 John Wiley & Sons, Ltd. [source] Investigation on visible emission control of ZnO thin filmPHYSICA STATUS SOLIDI (C) - CURRENT TOPICS IN SOLID STATE PHYSICS, Issue 10 2004Hong Seong Kang Abstract ZnO thin films were deposited on various substrates and ZnO-Si-ZnO multi-layer thin films were fabricated by pulsed laser deposition (PLD). ZnO thin films showed the three photoluminescence bands centered at around ultraviolet (380 nm), green (490,530 nm) and orange (570,640 nm) region. The region and intensity of visible emission of ZnO thin films were controlled as substrate and annealing treatment. As-grown ZnO thin film showed strong ultraviolet (UV) emission. ZnO thin films on (001) Al2O3 showed the increase of green emission caused by oxygen vacancies in the range of 490 nm to 530 nm, those on (100) InP showed the increase of orange emission caused by oxygen interstitials in the range of 610 nm to 640 nm. The increase of orange emission caused by oxygen interstitials was also observed from ZnO-Si-ZnO multi-layer thin films. The visible emission mechanism of ZnO was investigated. (© 2004 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [source] Separation of VOCs from N2 using poly(ether block amide) membranesTHE CANADIAN JOURNAL OF CHEMICAL ENGINEERING, Issue 3 2009Li Liu Abstract This work deals with the separation of volatile organic compounds (VOCs) from nitrogen streams for organic vapour emission control by poly(ether block amide) membranes. As representative air pollutant VOCs, n -pentane, n -hexane, cyclohexane, n -heptane, methanol, ethanol, n -propanol, n -butanol, acetone, dimethyl carbonate, and methyl tert -butyl ether were used in this study. The separation of both binary VOC/N2 and multicomponent VOCs/N2 gas mixtures was carried out, and the membranes exhibited good separation performance. A VOC concentration of more than 90 mol% was achieved at a feed VOC concentration of 5 mol%. It was found that the permeances of the VOCs were mainly dominated by their solubilities in the membrane, whereas the permeance of N2 was affected by the presence of the VOCs. The permeance of N2 in the VOC/N2 mixtures was shown to be higher than pure N2 permeance due to membrane swelling induced by the VOCs dissolved in the membrane. Nevertheless, theVOC/N2 selectivity increased with an increase in the feed VOC concentration. Among the VOCs studied, the membrane showed a higher permeance to alcohol VOCs than paraffin VOCs. The effects of feed VOC concentration, temperature, stage cut, and permeate pressure on the separation performance were investigated. Ce travail porte sur la séparation des composés organiques volatils (COV) présents dans des courants d'azote pour le contrôle des émissions de vapeur organique par des membranes de poly(éther amide bloc). Comme polluants atmosphériques représentatifs des COV, on a utilisé dans cette étude le n-pentane, le n-hexane, le cyclohexane, le n-heptane, le méthanol, l'éthanol, le n-propanol, le n-butanol, l'acétone, le carbonate de diméthyle et le méthyl tertio-butyl. On a procédé à la séparation du mélange de gaz de COV/N2 binaire et du mélange de gaz multicomposant COV/N2, et les membranes montrent une bonne performance de séparation. Une concentration de COV de plus de 90% en poids moléculaire a été obtenue à une concentration d'alimentation de COV de 5% en poids moléculaire. On a trouvé que les perméances de N2 était sensibles à la présence de COV. La perméance de N2 dans les mélanges de COV/N2 s'avère plus élevée que la perméance du N2 pur en raison du gonflement de la membrane provoqué par les COV dissous dans la membrane. Néanmoins, la sélectivité des COV/N2 augmente avec la concentration de COV d'alimentation. Parmi les COV étudiés, la membrane montre la plus haute perméance aux COV d'alcool qu'aux COVde paraffine. Les effets de la concentration de COV d'alimentation, de la température, la coupure de phase et la pression des perméats ont été étudiés. [source] | ||||||||||||||||