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11.
Aderholz M Aggarwal MM Akbari H Allport PP Badyal SK Ballagh HC Barth M Baton JP Bingham HH Brucker EB Burnstein RA Campbell JR Cence RJ Chatterjee TK Clayton EF Corrigan G Coutures C DeProspo D Devanand De Wolf EA Faulkner PJ Foeth H Fretter WB Gupta VK Hanlon J Harigel G Harris FA Jabiol MA Jacques P Jain V Jones GT Jones MD Kafka T Kalelkar M Kasper P Kohli JM Koller EL Krawiec RJ Lauko M Lys JE Marage P Milburn RH Miller DB Mittra IS Mobayyen MM Moreels J Morrison DR Myatt G Nailor P 《Physical review D: Particles and fields》1992,45(7):2232-2243
12.
Willocq S Aderholz M Akbari H Allport PP Badyal SK Ballagh HC Barth M Bingham HH Brucker EB Burnstein RA Cence RJ Chatterjee TK Clayton EF Corrigan G De Prospo D Devanand De Wolf E Faulkner PJ Foeth H Fretter WB Gupta VK Hanlon J Harigel G Harris FA Jacques P Jain V Jones GT Jones MD Kafka T Kalelkar M Kohli JM Koller EL Krawiec RJ Lauko M Lys JE Marage P Milburn RH Mittra IS Mobayyen MM Moreels J Morrison DR Myatt G Nailor P Naon R Napier A Passmore D Peters MW Peterson VZ Plano R Rao NK 《Physical review D: Particles and fields》1993,47(7):2661-2674
13.
K. P. Harikrishnan G. Ambika R. Misra 《The European physical journal. Special topics》2013,222(3-4):839-846
Transition to hyperchaos is uaually studied by computing the spectrum of Lyapunov Exponents (LE). But such a procedure can be employed mainly when the equations governing the dynamical system are known. However, if the information available on the system is only through time series, the method becomes difficult to implement. We show that the transition to hyperchaos is followed by a sudden change in the topological structure of the underlying attractor. Our numerical results indicate that the transition to hyperchaos can be characterized accurately through the computation of correlation dimension (D 2) from time series. We use two standard time delayed hyperchaotic systems as examples since, for such systems, D 2 varies smoothly as a function of the time delay τ which can be used as the control parameter. 相似文献
14.
15.
Vinod Singh Sambyal K. N. Goswami Ravi Kant Khajuria 《Crystal Research and Technology》1995,30(6):817-823
C8H12O3N2, Mr = 184.19, Trigonal, R3 (hexagonal axes) a = b = 26.800(1) Å, c = 6.828(3) Å, α = β = 90°, γ = 120°, V = 4247.11 Å3, Z = 18, Dm = 1.297 Mg m−3, Dc = 1.296 Mg m−3, mu = 0.79 mm−1, F(000) = 1764, T = 293 K, final R = 0.080 for 1205 observed reflections. There are two crystallographically independent molecules in the unit cell of the title compound. 相似文献
16.
A convenient and efficient one-pot multi-component synthesis of novel polysubstituted 4-amino-2,3-dihydropyridines from carbonyl compounds, malononitrile and acetonitrile, using indium triflate is reported. Acetonitrile acts both as a solvent as well as a substrate. 相似文献
17.
Dr. Ambika Bhagi-Damodaran Maximilian Kahle Yelu Shi Prof. Dr. Yong Zhang Prof. Dr. Pia Ädelroth Prof. Dr. Yi Lu 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2017,129(23):6722-6726
Heme-copper oxidase (HCO) is a class of respiratory enzymes that use a heme-copper center to catalyze O2 reduction to H2O. While heme reduction potential (E°′) of different HCO types has been found to vary >500 mV, its impact on HCO activity remains poorly understood. Here, we use a set of myoglobin-based functional HCO models to investigate the mechanism by which heme E°′ modulates oxidase activity. Rapid stopped-flow kinetic measurements show that increasing heme E°′ by ca. 210 mV results in increases in electron transfer (ET) rates by 30-fold, rate of O2 binding by 12-fold, O2 dissociation by 35-fold, while decreasing O2 affinity by 3-fold. Theoretical calculations reveal that E°′ modulation has significant implications on electronic charge of both heme iron and O2, resulting in increased O2 dissociation and reduced O2 affinity at high E°′ values. Overall, this work suggests that fine-tuning E°′ in HCOs and other heme enzymes can modulate their substrate affinity, ET rate and enzymatic activity. 相似文献
18.
In this paper we consider the Riemann problem for gas dynamic equations governing a one dimensional flow of van der Waals gases. The existence and uniqueness of shocks, contact discontinuities, simple wave solutions are discussed using R-H conditions and Lax conditions. The explicit form of solutions for shocks, contact discontinuities and simple waves are derived. The effects of van der Waals parameter on the shock and simple waves are studied. A condition is derived on the initial data for the existence of a solution to the Riemann problem. Moreover, a necessary and sufficient condition is derived on the initial data which gives the information about the existence of a shock wave or a simple wave for a 1-family and a 3-family of characteristics in the solution of the Riemann problem. 相似文献
19.
Papia Datta Ambika Prasad Mukhopadhyay César J. Pastor 《Journal of organometallic chemistry》2011,696(2):488-166
Cr, Mo and W tetracarbonyl complexes of 2-(2-pyridyl)benzoxazole (PBO) and 2-(2-pyridyl)benzothiazole (PBT) are spectroscopically characterised. The confirmatory structure of [Mo(CO)4(PBO)] has been determined by X-ray crystallography. The complexes show negative solvatochromic effect, with increasing solvent polarity the MLCT band is shifted to longer wavelength region. Cyclic voltammetry shows M(I)/M(0) redox response and also exhibit fluorescence spectra at room temperature. The electronic structures of the complexes are calculated by density functional theory (DFT) and time dependent-DFT calculated results are used to explain redox property and electronic transitions. 相似文献
20.
Financial data has been extensively studied for correlations using Pearson’s cross-correlation coefficient ρ as the point of departure. We employ an estimator based on recurrence plots — the correlation of probability of recurrence (CPR) — to analyze connections between nine stock indices spread worldwide. We suggest a slight modification of the CPR approach in order to get more robust results. We examine trends in CPR for an approximately 19-month window moved along the time series and compare them to trends in ρ. Binning CPR into three levels of connectedness (strong, moderate, and weak), we extract the trends in number of connections in each bin over time. We also look at the behavior of CPR during the dot-com bubble by shifting the time series to align their peaks. CPR mainly uncovers that the markets move in and out of periods of strong connectivity erratically, instead of moving monotonically towards increasing global connectivity. This is in contrast to ρ, which gives a picture of ever-increasing correlation. CPR also exhibits that time-shifted markets have high connectivity around the dot-com bubble of 2000. We use significance tests using twin surrogates to interpret all the measures estimated in the study. 相似文献