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61.
Piyachai Khomein Subramani Swaminathan Elizabeth R. Young S. Thayumanavan 《Journal of Inorganic and Organometallic Polymers and Materials》2018,28(2):407-413
Incorporation of a pyrene chromophore on the surface of polymeric nanoparticles results in its fluorescence enhancement. Quantum yield and lifetime measurements suggest that the enrichment in fluorescent signal is due to the increase in the rigidity of the environment surrounding the fluorophores and that it is dependent on the particle size. 相似文献
62.
Dr R. Ravi Ligy Philip T. Swaminathan 《Journal of chemical technology and biotechnology (Oxford, Oxfordshire : 1986)》2010,85(5):634-639
BACKGROUND: Bioreactors used for waste gas and odor treatment have gained acceptance in recent years to treat volatile organic compounds (VOCs). Different types of bioreactors (biofilter, biotrickling filter and rotating biological reactor) have been used for waste gas treatment. Most studies reported in the literature have used one of these systems to treat several types of inorganic and organic gases either individually or in mixtures. Each of these reactors has some advantages and some limitations. Though biodegradation is the main process for the removal of pollutants, the mechanisms of removal and the microbial communities may differ among these bioreactors. Consequently their performance or removal efficiency may also be different. RESULTS: At low loading rate (<35 g m?3 h?1), all three bioreactors showed comparable removal efficiencies and elimination capacity, but at higher loading rates, rotating biological contactors (RBC) showed a better performance with higher removal efficiency (40–50%) than both the biofilter and biotrickling filter (20–40%). The biofilter showed a sharp drop in removal efficiency and elimination capacity at high loading rates. CONCLUSIONS: The modified RBC had no clogging problems and no increase in pressure drop when compared with the other bioreactors. It can thus handle pollutant load for a longer period of time. This is the first study attempting to compare the performance of three different bioreactors for removal of the same VOC under different conditions. Copyright © 2010 Society of Chemical Industry 相似文献
63.
64.
Kobus Barnard Quanfu Fan Ranjini Swaminathan Anthony Hoogs Roderic Collins Pascale Rondot John Kaufhold 《International Journal of Computer Vision》2008,77(1-3):199-217
We present a new data set of 1014 images with manual segmentations and semantic labels for each segment, together with a methodology
for using this kind of data for recognition evaluation. The images and segmentations are from the UCB segmentation benchmark
database (Martin et al., in International conference on computer vision, vol. II, pp. 416–421, 2001). The database is extended by manually labeling each segment with its most specific semantic concept in WordNet (Miller et al.,
in Int. J. Lexicogr. 3(4):235–244, 1990). The evaluation methodology establishes protocols for mapping algorithm specific localization (e.g., segmentations) to our
data, handling synonyms, scoring matches at different levels of specificity, dealing with vocabularies with sense ambiguity
(the usual case), and handling ground truth regions with multiple labels. Given these protocols, we develop two evaluation
approaches. The first measures the range of semantics that an algorithm can recognize, and the second measures the frequency
that an algorithm recognizes semantics correctly. The data, the image labeling tool, and programs implementing our evaluation
strategy are all available on-line (kobus.ca//research/data/IJCV_2007).
We apply this infrastructure to evaluate four algorithms which learn to label image regions from weakly labeled data. The
algorithms tested include two variants of multiple instance learning (MIL), and two generative multi-modal mixture models.
These experiments are on a significantly larger scale than previously reported, especially in the case of MIL methods. More
specifically, we used training data sets up to 37,000 images and training vocabularies of up to 650 words.
We found that one of the mixture models performed best on image annotation and the frequency correct measure, and that variants
of MIL gave the best semantic range performance. We were able to substantively improve the performance of MIL methods on the
other tasks (image annotation and frequency correct region labeling) by providing an appropriate prior. 相似文献
65.
K. Mani Rahulan G. Vinitha L. Devaraj Stephen Charles Christopher Kanakam 《Ceramics International》2013,39(5):5281-5286
ZrO2 nanoparticles were synthesized by the chemical precipitation method and coated with silica through seeded polymerization technique to form core–shell type ZrO2@SiO2 nanostructures. The structural, morphological and silica coating formation of the bare and silica coated particles were studied using Transmission electron microscopy, X-ray diffraction and Fourier Transform Infrared Spectroscopy. Thermogravimetric analysis and Zeta potential measurements were performed to check the thermal and dispersion stability of the nanostructures. The optical limiting performance of these nanostructures was studied using open-aperture Z-scan technique in which nanosecond laser pulses at 532 nm have been used for optical excitation. Both bare and silica coated ZrO2 nanoparticles exhibited good optical limiting behavior due to excited state absorption, arising from effective three photon absorption. It is observed that the optical nonlinearity is enhanced in core shell structures as compared with the bare particles. 相似文献
66.
Thermogravimetric analysis (TGA) was used to examine the thermal behavior of Fosterton oil mixed with reservoir sand. TGA experiments were performed in nitrogen and air atmospheres at the heating rate of 10 °C/min up to 800 °C. In this study, four sets of TGA runs were performed to examine the thermal behavior of Fosterton whole oil, and the coke sample derived from the whole oil. Similar to previous studies in the literature, we also observed low-temperature oxidation (LTO), fuel deposition (FD), and high-temperature oxidation (HTO) in the non-isothermal combustion experiment. Higher activation energy values were obtained in reaction regions at higher temperatures. The mean activation energy for whole oil in nitrogen and air atmospheres was 33 and 126 kJ/mol, respectively. Fresh coke samples derived from whole oil were subjected to isothermal combustion at different temperatures from 375 to 500 °C. Arrhenius model was used to obtain the kinetic parameters from the TGA data. From the model, the Arrhenius parameters such as activation energy (E = 127 kJ/mol) and the pre-exponential factor (A = 1.6 × 108/min) were determined for the coke combustion. The results showed a close agreement between the kinetic model and experimental data for different combustion temperatures. It was observed that the apparent order of combustion reaction for different temperatures approach unity. 相似文献
67.
P. V. Prabhakaran K. J. Sreejith B. Swaminathan S. Packirisamy K. N. Ninan 《Journal of Materials Science》2009,44(2):528-533
Phenol-furfuraldehyde (PFu) resin synthesized in our laboratory was characterized for its thermal properties and mixed with
elemental silicon and the mixture was evaluated as precursor for SiC ceramics. The mix on sintering at 1,500 °C gave nano-SiC
powder. The sintering experiment carried out in flowing argon has also resulted in the formation of SiC wires/fibers having
diameter in nano to sub-micron range. 相似文献
68.
Pannala S. Bandyopadhyay J. Swaminathan M. 《Advanced Packaging, IEEE Transactions on》1999,22(3):249-258
This paper discusses the pulse propagation effects on lossy thin film planes. The ground bounce phenomena produced by the resonance on planes has been captured using a combination of modeling techniques and measurements. Macromodeling method has been used to explain the transient phenomena on planes by using the dominant poles and residues of the system 相似文献
69.
70.
An onboard hydrogen generation method based on hydrides and water recovery for micro-fuel cells 总被引:1,自引:0,他引:1
Micro-proton exchange membrane fuel cells are considered to be the next generation power sources for micro-scale power applications, but onboard hydrogen storage and generation with high energy density at the small scale is still a technical barrier. This paper introduces a hydrogen generation method based on an onboard hydride fuel and a byproduct water recovery mechanism for micro-hydrogen PEM fuel cells. The water recovery is carried out by water diffusion from the more humid cathode side to the less humid anode side through the proton exchange membrane. The micro-fuel cells based on this water recovery method were constructed and tested. The results demonstrate that the relative humidity has a significant affect on the fuel cell performance as well as the opening area on the cover layer, the type of hydrides, and the thickness of the Nafion membrane also can affect the fuel cell performance. A 10 mm3 prototype water recovery micro-fuel cell has been built and tested, and the device has produced a maximum power density of 104 W L−1 and a maximum energy density of 313 W h L−1. 相似文献