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84.
D. Mohan Ganga Radhakrishnan S. Rajadurai K. Venkata Rao Gordon G. Cameron 《Journal of polymer science. Part A, Polymer chemistry》1989,27(6):2123-2133
Polyacrylamide has been grafted onto casein in phosphate buffer medium using potassium peroxodisulfate as initiator. The influence of synthetic variables on percent grafting, grafting efficiency, rates of conversion of monomer, and the rates of graft copolymerization have been discussed. A possible kinetic scheme based on experimental results has been derived. 相似文献
85.
G. Mohan Rao T. S. Panchapagesan S. Mohan 《Applied Physics A: Materials Science & Processing》1990,51(5):423-426
Metal-insulator composites (cermets) find use in a wide range of applications. In this paper the preparation of cermet films by dc reactive magnetron sputtering is presented. These cermets have been characterised by measuring their electrical resistance and the properties have been correlated to the microstructure and composition. Magnetron sputtering is found to be very effective in controlling the composition of the deposited films, enabling the preparation of films with tailored properties. 相似文献
86.
Summary A short stainless steel column packed with silica gel is cooled to –78°C and atmospheric hydrocarbons are preconcentrated from 3 I of air on it. Desorption to the analytical column is by heating for 10 min to 200°C. Analysis is by GC on OPN-Poracil C at 27°C. The sorption efficiencies were nearly 100% for most of the light hydrocarbons. 相似文献
87.
The evolution of nonlinear Langmuir waves in the interplanetary medium is investigated by appropriately accounting for the
random density irregularities of the medium. A pair of modified Zakharov equations, which describe these waves, is solved
numerically as an initial value problem for large scale (≫ 102 km) initial pertubations. For an ion acoustic-Langmuir solitary wave, the random irregularities damp the Langmuir wave by
way of scattering and let the ion density perturbation radiate away in a few days. However an initial solitary or shock-like
Langmuir wave excites the ion density perturbations within a fraction of a second, and then itself gets damped. These effects
will strongly decelerate the collapse of large scale Langmuir waves. The possibility of detecting these processes, by means
of interplanetary scintillation, is discussed.
The authors felicitate Prof. D S Kothari on his eightieth birthday and dedicate this paper to him on this occasion. 相似文献
88.
Rahul Bhatt Sanjay K. Mishra D. Mohan A.K. Gupta 《Optics and Lasers in Engineering》2008,46(6):428-439
A fast holographic wavefront sensor is proposed using a computer-generated hologram (CGH). This CGH is a multiplexed hologram of different Zernike mode–amplitude combinations, and is designed in such a manner as to get the corresponding spots on the detector according to the presence and strength of a particular aberration. Interference between the aberrated wavefront (with a single mode–amplitude combination) and the Fourier transform of an image with single bright pixel (defined as dot image) is numerically calculated for one hologram. Different mode–amplitude combination and corresponding different positions of bright pixels (dots) are taken to compute various holograms and then all the holograms are multiplexed to get the final hologram. When the aberrated wavefront with a particular mode–amplitude combination is incident onto the multiplexed hologram, the corresponding dot is generated in the Fourier plane. A lens performs the Fourier transform in optical domain and provides the instant detection of amplitude of the respective Zernike mode. The main advantage of the scheme is to avoid the need of any computations, which makes it really fast. The simulation results are presented with the cross-talk analysis for few Zernike terms. 相似文献
89.
Shubhangi B. Umbarkar Trupti V. Kotbagi Ankush V. Biradar Renu Pasricha Jyoti Chanale Mohan K. Dongare Anne-Sophie Mamede Christine Lancelot Edmond Payen 《Journal of molecular catalysis. A, Chemical》2009,310(1-2):150-158
Acetalization of glycerol with various aldehydes has been carried out using mesoporous MoO3/SiO2 as a solid acid catalyst. A series of MoO3/SiO2 catalysts with varying MoO3 loadings (1–20 mol%) were prepared by sol–gel technique using ethyl silicate-40 and ammonium heptamolybdate as silica and molybdenum source respectively. The sol–gel derived samples were calcined at 500 °C and characterized using various physicochemical characterization techniques. The XRD of the calcined samples showed the formation of amorphous phase up to 10 mol% MoO3 loading and at higher loading of crystalline α-MoO3 on amorphous silica support. TEM analyses of the materials showed the uniform distribution of MoO3 nanoparticles on amorphous silica support. Raman spectroscopy showed the formation of silicomolybdic acid at low Mo loading and a mixture of α-MoO3 and polymolybdate species at high Mo loadings. Moreover the Raman spectra of intermediate loading samples also suggest the presence of β-MoO3. Acetalization of glycerol with benzaldehyde was carried out using series of MoO3/SiO2 catalysts with varying MoO3 loadings (1–20 mol%). Among the series, MoO3/SiO2 with 20 mol% MoO3 loadings was found to be the most active catalyst in acetalization under mild conditions. Maximum conversion of benzaldehyde (72%) was obtained in 8 h at 100 °C with 60% selectivity for the six-membered acetal using 20% MoO3/SiO2. Interestingly with substituted benzaldehydes under same reaction conditions the conversion of aldehydes decreased with increase in selectivity for six-membered acetals. These results indicate the potential of this catalyst for the acetalization of glycerol for an environmentally benign process. 相似文献
90.
S. Veer Raghavulu S. Venkata Mohan R. Kannaiah Goud P.N. Sarma 《Electrochemistry communications》2009,11(2):371-375
The performance of dual chambered microbial fuel cell (MFC, Nafion 117, non-catalyzed graphite electrodes) in concurrence with anodic pH microenvironment was evaluated based on bioelectricity generation and wastewater treatment efficiency. Experiments were carried out at different anodic pH microenvironments (acidophilic (6), neutral (7) and alkaline (8)) using both aerated and ferricyanide catholytes with mixed consortia as anodic biocatalyst employing chemical wastewater. Acidophilic pH in anodic chamber showed effective performance with respect to power output compared to the corresponding neutral and alkaline operations. However, substrate degradation was observed to be higher at neutral condition followed by alkaline and acidophilic operations. Ferricyanide as catholyte showed positive influence on the power output parameters compared to aerated catholyte. Nature of the catholyte did not show any visible influence on the wastewater treatment efficiency. 相似文献