排序方式: 共有5条查询结果,搜索用时 15 毫秒
1
1.
NANDINI CHATTERJEE SINGH 《Pramana》2011,77(5):811-816
Sounds in the natural environment form an important class of biologically relevant non-stationary signals. We propose a dynamic
spectral measure to characterize the spectral dynamics of such non-stationary sound signals and classify them based on rate
of change of spectral dynamics. We categorize sounds with slowly varying spectral dynamics as simple and those with rapidly
changing spectral dynamics as complex. We propose rate of spectral dynamics as a possible scheme to categorize sounds in the
environment. 相似文献
2.
JIN Ye ZHANG Wei-yu MENG Qing-fan LI Dan-hui GARG Sajay TENG Li-rong WEN Jing-yuan 《高等学校化学研究》2013,29(4):667-670
The degradation of flavonol glycosides extracted from Ginkgo biloba was performed under different conditions and the degraded products were determined by reversed-phase high performance liquid chromatography (RP-HPLC) method. Four stress conditions including acid(0.1 mol/L HCl), base(0.1 mol/L NaOH), temperature (70 ℃) and oxidation(0.03% H2O2, volume fraction) were used for the forced degradation studies. The pH stabilities of the flavonol glycosides were determined in phosphate buffers of varying pH values from 4.5 to 7.4. The degradation rate constants and half-life of three Ginkgo flavonol aglycones(quercetin, kaempferol and isorhamnetin) which represent Ginkgo flavonol glycosides were calculated in forced degradation and pH-stability studies of them. The results indicate that the three substances were more stable when incubated under acid condition and showed pH-dependent stability. The degradation was observed to follow first-order kinetics in all degradation studies. The stability results could provide important bases on development, preparation and storage of products of Ginkgo biloba extract and should be significantly considered during the further formulation development. 相似文献
3.
The matrix model of (simplified) RNA folding with an external linear interaction in the action of the partition function is
reviewed. The important results for structure combinatorics of the model are discussed and analysed in terms of the already
existing models. 相似文献
4.
K K PANDEY H K POSWAL A K MISHRA ABHILASH DWIVEDI R VASANTHI NANDINI GARG SURINDER M SHARMA 《Pramana》2013,80(4):607-619
An energy-dispersive X-ray diffraction beamline has been designed, developed and commissioned at BL-11 bending magnet port of the Indian synchrotron source, Indus-2. The performance of this beamline has been benchmarked by measuring diffraction patterns from various elemental metals and standard inorganic powdered samples. A few recent high-pressure investigations are presented to demonstrate the capabilities of the beamline. 相似文献
5.
Supersymmetric see-saw slow roll inflection point inflation occurs along a MSSM D-flat direction associated with gauge invariant combination of Higgs, slepton and right-handed sneutrino at a scale set by the right-handed neutrino mass \(M_{{\nu }^{c}} \sim 10^{6}\!\,-\,\!10^{13}\) GeV. The tensor to scalar perturbation ratio r~10?3 can be achieved in this scenario. However, this scenario faced difficulty in being embedded in the realistic new minimal supersymmetric SO(10) grand unified theory (NMSO(10)GUT). The recent discovery of B-mode polarization by BICEP2, changes the prospects of NMSO(10)GUT inflation. Inflection point models become strongly disfavoured, as the trilinear coupling of SUSY see-saw inflation potential gets suppressed relative to the mass parameter favoured by BICEP2. Large values of r≈0.2 can be achieved with super-Planck scale inflaton values and mass scales of inflaton ≥10 13 GeV. In NMSO(10)GUT, this can be made possible with an admixture of heavy Higgs doublet fields, i.e., other than MSSM Higgs field, which are present and have masses of order GUT scale. 相似文献
1