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411.
Ganguly R Aswal VK Hassan PA Gopalakrishnan IK Yakhmi JV 《The journal of physical chemistry. B》2005,109(12):5653-5658
Dynamic light scattering (DLS), small-angle neutron scattering (SANS), and viscosity studies have been carried out to examine the influence of NaCl and ethanol on the structure of triblock copolymer [(EO)20(PO)70(EO)20] (EO = ethylene oxide; PO = propylene oxide) micelles in aqueous medium. The studies show that while the pure triblock copolymer solutions do not show any significant growth of the micelles on approaching the cloud point, the presence of a small amount of ethanol (5-10%) induces a sphere to rod shape transition of micelles at high temperatures. Interestingly, this ethanol induced sphere to rod transition of micelles can be brought down to room temperature (25 degrees C) with the addition of NaCl. It is also found that NaCl alone cannot induce such sphere to rod transitions and excess ethanol suppresses them by increasing their transition temperature. 相似文献
412.
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415.
Stability analysis of peer-to-peer networks against churn 总被引:1,自引:0,他引:1
Users of the peer-to-peer system join and leave the network randomly, which makes the overlay network dynamic and unstable
in nature. In this paper, we propose an analytical framework to assess the robustness of p2p networks in the face of user
churn. We model the peer churn through degree-independent as well as degree-dependent node failure. Lately, superpeer networks
are becoming the most widely used topology among the p2p networks. Therefore, we perform the stability analysis of superpeer
networks as a case study. We validate the analytically derived results with the help of simulation.
相似文献
416.
Ajay K. Bose Subhendu N. Ganguly Maghar S. Manhas William He Jeffrey Speck 《Tetrahedron letters》2006,47(19):3213-3215
A novel experimental procedure for chemical reactions has been devised that involves mixing and then freezing the reagents (organic solvent-free) to a sub-zero temperature such as −30 °C. This frozen mixture is exposed to microwave irradiation for a brief period of time. The use of pre-cooled reagents may give a single product not obtained by traditional microwave irradiation at room temperature. Interestingly, such a product may provide information about mechanisms by identifying the first step of a multiple step reaction. 相似文献
417.
S. Chakraborty H. P. Sharma S. S. Tiwary C. Majumder P. K. Prajapati S. Rai P. Popli M. Singh S. S. Bhattacharjee R. P. Singh S. Muralithar P. Banerjee S. Ganguly S. Kumar A. Kumar R. Palit 《Brazilian Journal of Physics》2017,47(4):406-410
High spin states in 127Xe have been investigated via 9Be induced fusion-evaporation reaction at 48 MeV. Spin and parity of excited states up to \( \sim \frac {47}{2} \hbar \) have been confirmed from angular correlation and linear polarization results. Rotational alignment of the second pair of h 11/2 neutrons has been observed at \(\hbar \omega \sim \) 0.44 MeV; beyond that, the band is associated with ν[h 11/2]3 configuration. The alignment phenomena has been discussed in comparison with the neighboring 125,129Xe. 相似文献
418.
Optical properties of Cd1−xZnxTe thin films fabricated through sputtering of compound semiconductors
Cd1−xZnxTe thin film fabrication is necessary for its photovoltaic and imaging applications in large scale. Thermally annealed and thereby interdiffused r.f. sputtered multilayers comprising of CdTe and ZnTe have been utilized here for the fabrication of Cd1−xZnxTe thin films. Photoluminescence and change of resistance of the multilayer under illumination were studied using different annealing temperatures and varying number of repetitions. It was found that three number of repetitions annealed at 300 °C exhibited the best results. 相似文献
419.
Somenath Ganguly 《Transport in Porous Media》2010,81(3):443-460
During waterflooding of a fractured formation, water may channel through the fracture or interconnected network of fractures,
leaving a large portion of oil bearing rock unswept. One remedial practice is injection of a gelling solution into the fracture.
Such placement of a gelling mixture (referred as gelant) is associated with leak-off from the face of the fracture into the
adjoining matrix. As the gelant gets more crosslinked, the gelant encounters more resistance in flowing into the porous matrix.
This article addresses the build-up of flow resistance as the Cr(III)-partially hydrolyzed polyacrylamide gelant, at various
stages of crosslinking flows into the matrix. Flow experiments were conducted at constant injection pressure in unfractured
Berea rocks that represent a matrix adjoining a fracture. Before entering the core, gelants underwent post-mixing delays,
shorter than their gel time. On continued displacement, flow resistance developed that reduced the flow rate further. More
delay, after mixing of gelant hastened, the build-up of resistance to flow and the resistance was contained nearer to the
inlet face. Effect of flow over fracture face on the build-up of flow resistance in the matrix was also evaluated by conducting
displacement of gelant in two fractured slabs. In one case, a part of the injected fluid came out of the fracture outlet with
the rest leaking off into matrix. In the other case, all the fluid that entered into the fracture leaked off into the matrix.
Build-up of flow resistances in the matrix for the two cases was compared. A simple conceptual model is presented that could
explain the flow of gelant and build-up of resistance in porous rock at constant injection pressure. 相似文献
420.
The red-shift of the fluorescence bands from the excitation bands of 2,6-, 2,5-and 3,5-xylenol, measured in binary and ternary solutions at 300 K, is mainly due to dipole orientation, the hydrogen bond making only a small contribution In viscous media at 90 K, the fluorescence transition occurs from a partially relaxed equilibrium excited state. 相似文献