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81.
82.
Photocatalytic Degradation of Glyphosate in Water by N‐Doped SnO2/TiO2 Thin‐Film‐Coated Glass Fibers
Peerawas Kongsong Lek Sikong Sutham Niyomwas Vishnu Rachpech 《Photochemistry and photobiology》2014,90(6):1243-1250
Photocatalytic degradation of glyphosate contaminated in water was investigated. The N‐doped SnO2/TiO2 films were prepared via sol–gel method, and coated on glass fibers by dipping method. The effects of nitrogen doping on coating morphology, physical properties and glyphosate degradation rates were experimentally determined. Main variable was the concentration of nitrogen doping in range 0–40 mol%. Nitrogen doping results in shifting the absorption wavelengths and narrowing the band gap energy those lead to enhancement of photocatalytic performance. The near optimal 20N/SnO2/TiO2 composite thin film exhibited about two‐ and four‐folds of glyphosate degradation rates compared to the undoped SnO2/TiO2 and TiO2 films when photocatalytic treatment were performed under UV and solar irradiations, respectively, due to its narrowest band gap energy (optical absorption wavelength shifting to visible light region) and smallest crystallite size influenced by N‐doping. 相似文献
83.
Generalized Coupled Fixed Point Results on Complex Partial Metric Space Using Contractive Condition 下载免费PDF全文
Mani Gunaseelan Lakshmi Narayan Mishr Vishnu Narayan Mishra 《Journal of Nonlinear Modeling and Analysis》2021,3(1):93-104
In this paper, we obtain coupled fixed point results on complex partial metric space under contractive condition. An example to support our result is presented. 相似文献
84.
Vishnu K. Nithyaja B. Pradeep C. Sujith R. Mohanan P. Nampoori V. P. N. 《Laser Physics》2011,21(11):1945-1949
In the present study we have investigated the effect of mobile phone radiation on deoxyribonucleic acid by using fluorescence
technique. Absorption spectra shows increase in absorption of DNA after exposure to radiation from mobile phone with different
SAR values and microwave frequency which give information about unwinding of the DNA double strand. Fluorescence intensity
of dye doped DNA solution is getting reduced suggesting that the absorbed energy is used for unwinding of double strand of
DNA after irradiating with microwave radiation. Unwinding of the DNA is very sensitive to power of the microwave radiation. 相似文献
85.
We report two new formal cycloaddition reactions between nitrosobenzenes and alkenylgold carbenoids. We obtained quinoline oxides 3 in satisfactory yields from the gold-catalyzed [3 + 3]-cycloadditions between nitrosobenzenes and alkenyldiazo esters 1. For propargyl esters 5, its resulting gold carbenes react with nitrosobenzene to give alkenylimine 8, followed by a [4 + 2]-cycloaddition with nitrosobenzene. 相似文献
86.
R. Sanjeev Kumar V. Veeravazhuthi D. Vishnu Shankar N. Muthukumarasamy M. Thambidurai 《Journal of Sol-Gel Science and Technology》2014,71(1):152-158
ZnS and Co-doped ZnS nanoparticles have been prepared by simple chemical precipitation method. Zinc acetate, sodium sulfide, and cobalt nitrate have been used as precursors for the preparation of Co-doped ZnS quantum dots. The X-ray diffraction results revealed that the undoped and Co-doped ZnS quantum dots exhibit hexagonal structure. The average grain size of quantum dot was found to lie in the range of 2.6–3.8 nm. The surface morphology has been studied using scanning electron microscope. The compositional analysis results confirm the presence of Co, Zn and S in the sample. The optical properties of undoped and Co-doped ZnS quantum dots have been studied using absorption spectra. TEM results show that undoped and Co-doped ZnS nanoparticles exhibit a uniform size distribution with average size of 2.5–3.4 nm. 相似文献
87.
Based on XPS and UVPS studies, it is shown that oxygen is preferentially adsorbed molecularly in the singlet state on Cu and Ag surfaces containing presorbed chlorine. Adsorption of chlorine on Cu and Ag surfaces containing presorbed atomic oxygen causes a disappearance of the oxygen. Extended Hückel calculations predict the observed behaviour. 相似文献
88.
Nielsen and Olesen showed that perturbative vacuum with uniform chromomagnetic field in one space and one color direction
is unstable. This instability is called Nielsen-Olesen instability (NOI), and leads to formation of a ‘spaghetti of flux tubes’
as a model for non-perturbative vacuum and confinement. We re-examine this instability in presence of color sources, quarks
and gluons, at a finite temperature and find that at sufficiently high temperature NOI is stabilized due to an ‘effective
mass’ of gluons arising through plasma effects. This explains how a QGP with no confinement effects may exist at high temperature.
As the temperature is lowered, NOI reappears at a valueT=T
c, which is very close to confinement-deconfinement transition from hadrons to QGP.. 相似文献
89.
Albert H. Schroeder Frank B. Kaufman Vishnu Patel Edward M. Engler 《Journal of Electroanalytical Chemistry》1980,113(2):193-208
General methods are described for the synthesis of electroactive polymers and the preparation of uniform, stable, polymer-coated electrodes. The electrochemical behaviour of thin films of eight different functionalized polystyrenes, differing in the identity and amount of attached electroactive species, and polyvinylferrocene is presented. A wide range of electrochemical properties can be observed by varying parameters such as film thickness, nature of the bound redox couple, extent of polymer functionalization and oxidation state. The deviations from ideal surface behavior are investigated in detail. These are shown to be consequences of cooperative electronic interactions, structural reorganization or uncompensated resistance within the film, depending upon the material. The film resistance varies greatly among the polymer films studied and is shown, in some cases, to be a sensitive function of the extent of oxidation and prior treatment of the film. This variable resistance is shown to be a consequence of slow ion transport through the film. The mechanism of electron transport in such materials is considered and a model of the metal/polymer/electrolyte interface is proposed. 相似文献
90.
Absorption spectra of RbMnF3 in the 5500Å region were investigated in the temperature interval 4.2–77°K. Similar temperature dependence was observed for the exciton-magnon and the magnon-phonon sidebands. The position of the exciton lines does not vary as the temperature is increased. 相似文献