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231.
L. O. BJÖRN 《Photochemistry and photobiology》1971,13(1):5-20
Abstract— –Small amounts of N -methyl phenazonium methosulphate (PMS) added to a suspension of Chlorella pyrenoidosa accelerate the emission of the long-lived far-red induced afterglow without greatly changing the amount of light emitted. The effect is noticeable in dilute suspensions at a PMS concentration of 10-9 M. The concept of afterglow unit is introduced and defined as that part of the sample in which the rate of energy reemission can be controlled by a single molecule of PMS. The number of chlorophyll molecules per afterglow unit is about 105 . It is possible that the afterglow unit is identical to the thylakoid.
The rate constant for the final first order decay phase of afterglow at room temperature is about 0.7 min-1 without PMS and about 3 times larger for a unit with one PMS molecule.
Diuron (DCMU) lowers the rate of afterglow decay. Desaspidin on the other hand decreases the amount of light emitted without affecting the decay rate. Carbonylcyanide- m -chlorophenyl hydrazone (CCCP) decreases the afterglow over the whole time-range and increases the decay rate. A kinetic model is developed to account for the results. 相似文献
The rate constant for the final first order decay phase of afterglow at room temperature is about 0.7 min
Diuron (DCMU) lowers the rate of afterglow decay. Desaspidin on the other hand decreases the amount of light emitted without affecting the decay rate. Carbonylcyanide- m -chlorophenyl hydrazone (CCCP) decreases the afterglow over the whole time-range and increases the decay rate. A kinetic model is developed to account for the results. 相似文献
232.
Lakshminarasimhan Damodharan Nagarajarao Shamaladevi Vasantha Pattabhi Manoranjan Behera Sambasivarao Kotha 《Acta Crystallographica. Section C, Structural Chemistry》2002,58(5):o266-o267
The title compound, C20H21NO3, is a derivative of Aib (α‐aminoisobutyric acid) and is cyclized at the Cα position by biphenyl rings. The seven‐membered ring possesses C2 symmetry. The Cα cyclization causes the backbone to assume a helical conformation in the crystal structure. The packing of the molecules is stabilized by intermolecular C—H?O, C—H?π and N—H?O hydrogen bonds. 相似文献
233.
Using full-potential density functional calculations within local density approximation (LDA), we predict that mechanically tunable band-gap and quasi-particle-effective-mass are realizable in graphene/hexagonal-BN hetero-bilayer (C/h-BN HBL) by application of in-plane homogeneous biaxial strain. While providing one of the possible reasons for the experimentally observed gap-less pristine-graphene-like electronic properties of C/h-BN HBL, which theoretically has a narrow band-gap, we suggest a schematic experiment for verification of our results which may find applications in nano-electromechanical systems (NEMS), nano opto-mechanical systems (NOMS) and other nano-devices based on C/h-BN HBL. 相似文献
234.
Biswaranjan Behera 《Journal of Mathematical Analysis and Applications》2007,328(2):1237-1246
A multiresolution analysis was defined by Gabardo and Nashed for which the translation set is a discrete set which is not a group. We construct the associated wavelet packets for such an MRA. Further, from the collection of dilations and translations of the wavelet packets, we characterize the subcollections which form orthonormal bases for L2(R). 相似文献
235.
Bivash R Behera Subinit Roy P Basu M K Sharan S Jena M Satpathy SK Datta L Satpathy ML Chatterjee 《Pramana》1999,53(3):563-566
Time of flight and energy of fission fragments were measured using pulsed beam. Fission fragment mass and energy integrated
angular distributions were extracted. Fission fragment anisotropy was explained in the framework of saddle point model. 相似文献
236.
Annapurna Mohanta Dhrubananda Behera Simanchalo Panigrahi Naresh Chandra Mishra 《Indian Journal of Physics》2009,83(4):455-463
Ferroelectrics and high temperature superconductors are two promising materials for future electronic devices. Both being
perovskite ceramic structures with similar crystal chemistry a set of samples were prepared from the composite of (1−x)YBa2Cu307−δ
−(x)BaTiO3 (YBCO/BT). These samples were investigated with temperature dependent resistance, FTIR, X-ray diffraction and SEM-EDX analysis.
It has been found that the critical exponent in the T
c0 (R = 0) region is in agreement with the percolation theory. A long-range superconducting order results from thermally assisted
percolation process through weak-links between the grains. The connectivity in the coherent transition region can be explained
by a power law.
相似文献
237.
F. Schweitzer L. Behera 《The European Physical Journal B - Condensed Matter and Complex Systems》2009,67(3):301-318
In nonlinear voter models the transitions between two states depend in a nonlinear manner on the frequencies of these states
in the neighborhood. We investigate the role of these nonlinearities on the global outcome of the dynamics for a homogeneous
network where each node is connected to m = 4 neighbors. The paper unfolds in two directions. We first develop a general stochastic
framework for frequency dependent processes from which we derive the macroscopic dynamics for key variables, such as global
frequencies and correlations. Explicit expressions for both the mean-field limit and the pair approximation are obtained.
We then apply these equations to determine a phase diagram in the parameter space that distinguishes between different dynamic
regimes. The pair approximation allows us to identify three regimes for nonlinear voter models: (i) complete invasion; (ii)
random coexistence; and – most interestingly – (iii) correlated coexistence. These findings are contrasted with predictions
from the mean-field phase diagram and are confirmed by extensive computer simulations of the microscopic dynamics. 相似文献
238.
T. R. Rautray B. Behera T. Badapanda V. Vijayan S. Panigrahi 《Indian Journal of Physics》2009,83(4):543-546
Trace element analysis of some fly ash samples and soil samples have been carried out by Energy Dispersive X-Ray Fluorescence
technique. Fourteen elements namely K, Ca, Ti, V, Cr, Mn, Fe, Co, Cu, Zn, Se, Rb, Sr and Pb have been quantified in the fly
ash samples by this technique. It was found that there is no huge concentration difference between the fly ash and soil samples
as a result of which fly ash can be used as soil manure without any adverse impact on the plants.
相似文献
239.
Bivash R Behera Subinit Roy P Basu M K Sharan S Jena M Satpathy M L Chatter Jee S K Datta 《Pramana》2001,57(1):199-202
Anisotropies in fission fragment angular distributions measured for the system 16O + 181Ta over a range of bombarding energies from 83 MeV to 120 MeV have been analysed. It is shown that statistical transition
state model (TSM) with pre-scission neutron correction described adequately the measured anisotropy data. Strong friction
parameter is found to be necessary to estimate the pre-saddle to pre-scission neutron ratio. 相似文献
240.
Ishita Sarkar Samarshi Chakraborty Asmit Roshan Dinesh K. Behera Surjya K. Pal 《实验传热》2019,32(4):322-336
Cooling rate in Run Out Table (ROT) in steel industries tailors microstructure which lead to improved mechanical properties. The current work aims to increase cooling performance of steel using TiO2 nanofluid as coolant in jet impingement. Different concentrations of TiO2 nanofluid have been used to study effect on jet cooling of a steel plate from 900°C. Thermal conductivity of nanofluid is found to significantly enhance at optimum concentration and this plays major role in increasing cooling rate of the steel plate. 19% enhancement in cooling rate is observed by using 40 ppm of TiO2 nanofluid compared to water. 相似文献