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41.
Michael Koch Karthikeyan Perumal Dr. Olivier Blacque Dr. Jai Anand Garg Dr. Ramanathan Saiganesh Dr. Senthamaraikannan Kabilan Prof. Dr. Kallupattu Kuppusamy Balasubramanian Dr. Koushik Venkatesan 《Angewandte Chemie (International ed. in English)》2014,53(25):6378-6382
Design of highly efficient phosphorescent emitters based on metal‐ and heavy atom‐free boron compounds has been demonstrated by taking advantage of the singlet fission process. The combination of a suitable molecular scaffold and appropriate electronic nature of the substituents has been utilized to tailor the phosphorescence emission properties in solution, neat solid, and in doped PMMA thin films. 相似文献
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43.
Joginder N. Anand 《Journal of Macromolecular Science: Physics》2013,52(3):445-458
Polyethylene has an orthorhombic lattice for which nine elastic constants exist; they are obtained in terms of the intra- and intermolecular forces. Constants involved in the 6-12 Lennard-Jones potential approximating the London dispersion type of van der Waals' forces are obtained by computing the crystal potential energy and comparing it with the cohesive energy. First and second nearest-neighbor interactions are considered to establish relationship between the elastic constants and the interaction constants. The latter are obtained in terms of the C—C bond, stretching, bending, and repulsive force constants and the L-J potential constants. A limited type of central force assumption is applied. Values of Young and shear moduli are obtained along the three axes. The value along the chain compares with the experimentally determined and calculated values for oriented polyethylene. Young's modulus along the lateral direction is of the order of Young's modulus of bulk polyethylene, showing that intermo-lecular forces are the ones that determine the Young modulus of bulk polyethylene. 相似文献
44.
Lallit Anand 《International Journal of Solids and Structures》2011,48(6):962-971
In this paper we develop a thermodynamically-consistent coupled-theory which accounts for diffusion of hydrogen, diffusion of heat, and large elastic–viscoplastic deformations of metals. The theory should be of utility in the analysis of hydrogen diffusion in elastic–plastically-deforming solids, an analysis which is an essential prerequisite for theoretical and numerical efforts aimed at modeling the integrity of structural components used for hydrogen gas storage and distribution. 相似文献
45.
The stereoselective synthesis of (+)-goniodiol, a cytotoxic styryllactone, has been accomplished in 10 steps starting from inexpensive and readily available d-manitol and δ-gluconolactone involving the direct and straightforward reaction conditions of Grignard addition, chain elongation, and hydroboration, thus making the synthesis simple and convenient. 相似文献
46.
Dark currents n+/ν/p+ Hg0.69Cd0.31Te mid wave infrared photodiodes were measured at room temperature. The diodes exhibited negative differential resistance at room-temperature, but with increasing leakage currents as a function of reverse bias. The current–voltage characteristics were simulated and fitted by incorporating trap assisted tunneling via traps and Shockley–Read–Hall generation recombination process due to dislocations in the carrier transport equations. The thermal suppression of carriers was simulated by taking energy level of trap (Et), trap density (Nt) and the doping concentrations of n+ and ν regions as fitting parameters. Values of Et and Nt were 0.78Eg and ~6–9 × 1014 cm?3 respectively for most of the diodes. Variable temperature current voltage measurements on variable area diode array (VADA) structures confirmed the fact that variation in zero bias resistance area product (R0A) is related to g–r processes originating from variation in concentration and kind of defects that intersect a junction area. 相似文献
47.
Venkatraman S Anand VG PrabhuRaja V Rath H Sankar J Chandrashekar TK Teng W Senge KR 《Chemical communications (Cambridge, England)》2002,(16):1660-1661
First successful syntheses and structural characterization of new core modified meso aryl azuliporphyrins by a simple [3 + 1] methodology are reported. 相似文献
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49.
Extensive data now available on the non-thermal background radio emission from different celestial directions, and recent measurements on the energy spectrum of cosmic ray electrons in the vicinity of the earth permit one to deduce information on the mean magnetic fields and cosmic electron spectra needed to exist in different regions of the Galaxy. It is found that in order to explain quantitatively the background radio brightness distributions from the Galaxy one needs (i) the same or nearly same electron spectrum that exists in the near interstellar space, to exist in almost all regions of Galactic space, (ii) a mean magnetic field close to 6×10?6 Gauss in the Disc in the direction of the Anti-centre, (iii) a mean magnetic field close to 2·5×10?6 Gauss in the radio Halo and (iv) a mean magnetic field probably close to 9·5×10?6 Gauss towards the Galactic Ridge in the direction of the Centre. Some inferences are also drawn on the confinement of cosmic rays in the Galaxy. 相似文献
50.
Alkylation and deformylation of 2,2-dimethyl-3-hydroxymethylene-5-hydroxy-7-pentyl-4-chromone occurs in the same step to give the title compound. 相似文献