The effect off and Cl on Mn/TiO2 catalyst for selective catalytic reduction of NO with NH3 was investigated in this study. It was found that the doping off or Cl has a deactivation effect on Mn/TiO2 catalyst. And th...
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The effect off and Cl on Mn/TiO2 catalyst for selective catalytic reduction of NO with NH3 was investigated in this study. It was found that the doping off or Cl has a deactivation effect on Mn/TiO2 catalyst. And the poisoning effect of Cl is more serious than that off. The characterization results showed that the decrease of BET surface area, the increase of crystallinity, the reduced reducibility and surface acidity, and the decreased concentrations of surface Mn4+ and chemisorbed oxygen should be responsible for the deactivation of Mn/TiO2 catalyst by the doping off or Cl. (C) 2015 Elsevier B.V. All rights reserved.
Based on fluorescein, a novel water-soluble and reversible fluorescent probe (flu-Py) was designed and synthesized for the sequentially "ON-Off-ON" fluorescent detection of Al3+ and f- in concentration range...
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Based on fluorescein, a novel water-soluble and reversible fluorescent probe (flu-Py) was designed and synthesized for the sequentially "ON-Off-ON" fluorescent detection of Al3+ and f- in concentration range of 0-10 mu mol L-1 and 0-30 mu mol L-1, respectively, with high sensitivity and excellent selectivity. The detection limits for Al3+ and f- were 0.092 mu mol L-1 and 0.1 1 2 mu mol L-1, respectively. The binding mode and sensing mechanism offlu-Py with Al3+ was verified by density functional theory (DfT) and time dependent density functional theory (TDDfT) calculation. The "ON-Off-ON" fluorescent property offlu-Py upon the addition of Al3+ and f- was utilized for the imaging of living cells. (C) 2016 Elsevier B.V. All rights reserved.
In this paper, adaptive decision feedback-based model is used to design an efficient equalizer to mitigate the detrimental effects during the signal transmission through wireless channels having non-ideal frequency re...
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In this paper, adaptive decision feedback-based model is used to design an efficient equalizer to mitigate the detrimental effects during the signal transmission through wireless channels having non-ideal frequency response. The proposed adaptive equalizer is designed using normalized block least mean square/fourth algorithm which yields low bit error rate and mean square error in spite of high noisy and fading channel conditions. The constellations as well as eye diagrams are also taken as performance measuring criteria for indoor wireless channel which is designed by using IEEE 802.11 model with exponential power delay profile. The channel capacity using the proposed model is also analyzed to verify the system performance. Combination of block processing approach and the elegant structure of the equalizer achieves higher symbol estimation accuracy and stable convergence which is quite suitable for indoor fading channel characteristics. The performance comparison of the proposed model is presented with detail simulation results.
The study includes the determination of the general background PCDD/f and dl-PCB levels in environmental (ambient air and soil) and food (meat, milk, egg, leafy vegetable, root vegetable and fruit samples) samples col...
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The study includes the determination of the general background PCDD/f and dl-PCB levels in environmental (ambient air and soil) and food (meat, milk, egg, leafy vegetable, root vegetable and fruit samples) samples collected in four sampling sites in the vicinity of IZAYDAS WIP and its possible health risks. The local and meteorological conditions (prevailing wind direction, season, raining, and soil structure) were taken into account in the selection of sampling sites. The concentrations of PCDD/f and dl-PCB in ambient air ranged from 0.00841 to 0.05881 pg I-TEQ/m(3). These results are quite low and it showed that there is no significant PCDD/f pollution in the vicinity of the plant. The results of PCDD/f and dl-PCB in eight soil samples (four in the range of 0-1.2 km, four in the range of 1.2-5 km) taken from the vicinity of IZAYDAS varied between 0.12681 and 0.4353 pg TEQ/g. The levels of PCDD/f and dl-PCBs measured in food samples were found to be significantly lower than both the limit values given by the Turkish food Codex and the levels measured in the previous studies (between 2008 and 2009). In the health risk assessment, carcinogenic risk was calculated for PCDD/f and dl-PCBs made according to the exposure scenarios established for the study. The total intake values for the sum of PCDD/f and dl-PCB were found between 0.08 and 0.37 pg TEQ/*** for adults. These values are well below the limit value, which is considered as 2 pg WHO-TEQ/kg body ***. In this context, it was concluded that carcinogenic risk due to PCDD/f and dl-PCB intake is significantly low in the vicinity of the plant.
The multiple scattering Xα(MSXα) method is used in the study of the f + -centre in the alkaline earth oxides. The isotropic hyperfine constant and the optical absorption energies are evaluated. The calculated hyperf...
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The multiple scattering Xα(MSXα) method is used in the study of the f + -centre in the alkaline earth oxides. The isotropic hyperfine constant and the optical absorption energies are evaluated. The calculated hyperfine constants are in good agreement with the experimental values. for the optical transition energies, agreement between the calculated and experimental values is somewhat poor. Nevertheless, the results show the expected decreasing behavior with increasing atomic number of the alkaline earth atom.
The electronic structures of PbWO4 crystals containing f type color centers with the lattice structure optimized are studied within the framework of the fully relativistic self-consistent Direc-Slater theory, using a ...
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The electronic structures of PbWO4 crystals containing f type color centers with the lattice structure optimized are studied within the framework of the fully relativistic self-consistent Direc-Slater theory, using a numerically discrete variational (DV-X alpha) method. The calculated results show that f and f+ centers have donor energy level in forbidden band. Their optical transition energy are 1.84 eV, 2.21 eV, respectively, which corresponds to the 680 nm, 550 nm absorption bands. It predicts that the 680 nm, 550 nm absorption bands originate form the f and P centers in PbW04 crystals. (c) 2005 Elsevier B.V. All rights reserved.
The rheology of three melt compositions containing different amounts offluorine (f) and chlorine (Cl) or both was investigated with micropenetration and parallel-plate techniques. The heat capacity and configurationa...
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The rheology of three melt compositions containing different amounts offluorine (f) and chlorine (Cl) or both was investigated with micropenetration and parallel-plate techniques. The heat capacity and configurational entropy of the melts were also determined. The observed viscosity range is between 10(5.5) and 10(13) Pa s. The melts were produced in a 1 atm furnace at temperatures between 1523 and 1923 K using oxide and carbonate compounds. The halogens were incorporated using halides and halogen-bearing ammonium compounds. The first composition is a peraluminous Na2O-CaO-Al2O3-SiO2 melt (ANCS) with an apparent NBO/T of similar to-0.08, the second composition is a peralkaline Na2O-CaO-Al2O3-SiO2 melt (NACS) (NBO/T = similar to 0.24), which is an analogue for phonolites, and the third is an aluminium-free Na2O-CaO-SiO2 melt (NCS) (NBO/T of similar to 0.68). five halogen-bearing ANCS melts with up to 1.10 mol% Cl and 1825 mol% f, 6 halogen-bearing NACS melts with up to 138 mol% Cl and 2.58 mol% f and 3 halogen-bearing NCS melts with up to 2.15 mol% Cl and 2.04 mol% f were investigated in this study. fluorine was found to decrease the viscosity for all compositions, but not with equal strength. Interpolated to 1 mol%, f decreases the viscosity by 0.31 +/- 0.08 log units in the peraluminous melt (ANCS), 0.57 +/- 0.11 log units in the peralkaline melt (NACS) and 0.47 +/- 0.14 log units in the NCS melt. The effect of Cl on rheology depends on the melt composition. Interpolated to 1 mol%, Cl decreases the viscosity by 0.57 +/- 0.13 log units in the peraluminous melt, but increases viscosity by 0.87 +/- 0.10 log units in the peralkaline melt. There is no measurable effect on viscosity due to the addition of chlorine to the aluminium-free melt. In the peraluminous melts the effects off and Cl add almost linearly to decrease viscosity. In the peralkaline melts, Cl increases the viscosity while f decreases it, if both are present, the effects appear to balance each other;re
Metal-composite airframes will suffer various defects during their lifetime. One category of defects is composite laminate delamination. This study evaluates the criticality of delaminations existing around adjacent f...
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Metal-composite airframes will suffer various defects during their lifetime. One category of defects is composite laminate delamination. This study evaluates the criticality of delaminations existing around adjacent fastener holes in the carbon-fibre-reinforced plastic spar web of the f/A-18 aircraft's trailing-edge flap. The evaluation is based on experiments and analyses. first, an intensive experimental program for determining necessary material values off/A-18 is described. Multiple delaminations of the flap spar web are then modelled by varying the set of delaminated hole edges and the interface of delamination. The interaction of defects at the start of delamination propagation is studied via the developed interaction parameter. The results suggest that the interaction parameter can show significant differences in the interaction per delamination case and that the interface of delamination is an important variable. finally, operator-dependent control parameters are studied, and it is found that the criticality of a delamination case is merely dependent on true material parameters.
Extending recent suggestions regarding the vibronic properties off -centers in alkali halides, the following scenario is now proposed of the optical conversion off -centers into f ′-centers: An excited f -center el...
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Extending recent suggestions regarding the vibronic properties off -centers in alkali halides, the following scenario is now proposed of the optical conversion off -centers into f ′-centers: An excited f -center electron, formed by photobleaching in the f -band, passes into a bound polaron state before passing on to an f -center to give rise to an f ′-center. The detachment of the electron cloud from the excited f -center involves configurational tunneling in an exothermic process. However, both the tunneling barrier and the electron-transfer expectancy depend drastically on the host material leading to different activation energies and frequency factors of the conversion efficiency in different hosts. The f center-polaron conversion is effected through the strong coupling to at least two modes, one being the LO lattice mode of the crystal. The f to f ′ conversion efficiency for various hosts is calculated using a reaction-rate method and found to agree reasonably well with available experimental data.
This paper presents the theoretical analysis of the Class-E/f-3 power amplifier (PA) with nonlinear shunt capacitor at different grading coefficient (m), for both optimum (i.e., ZVS and ZVDS) and suboptimum (i.e., ZVS...
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This paper presents the theoretical analysis of the Class-E/f-3 power amplifier (PA) with nonlinear shunt capacitor at different grading coefficient (m), for both optimum (i.e., ZVS and ZVDS) and suboptimum (i.e., ZVS and non-ZVDS) operations. The effects that the grading coefficient has on the load network parameters, maximum operating frequency, and the peak switch voltage and current are investigated in details for m = 0 up to m = 0.8. Three design examples are given to explain the design procedure, and two circuit prototypes were built using power MOSfETs with m = 0.3 and m = 0.5 to validate the theory. The constructed PAs delivered an output power of 3.5 W/2.55 W and a drain efficiency of 92.3%/92% at an operating frequency of 3.8/3.85 MHz, respectively.
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