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11.
Razavet M Borg SJ George SJ Best SP Fairhurst SA Pickett CJ 《Chemical communications (Cambridge, England)》2002,(7):700-701
Iron(I) in biology?: one-electron oxidation of an (Fe(I)-Fe(I)) carbonyl cyanide precursor bearing a proximal thioether group leads to an (Fe(I)-Fe(II)) bridging carbonyl transient with spectral features similar to the di-iron sub-site of the CO inhibited paramagnetic centre of all-iron hydrogenase. 相似文献
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Jaehoon Lim Lisa zur Borg Stefan Dolezel Friederike Schmid Kookheon Char Rudolf Zentel 《Macromolecular rapid communications》2014,35(19):1685-1691
The morphology or dispersion control in inorganic/organic hybrid systems is studied, which consist of monodisperse CdSe tetrapods (TPs) with grafted semiconducting block copolymers with excess polymers of the same type. Tetrapod arm‐length and amount of polymer loading are varied in order to find the ideal morphology for hybrid solar cells. Additionally, polymers without anchor groups are mixed with the TPs to study the effect of such anchor groups on the hybrid morphology. A numerical model is developed and Monte Carlo simulations to study the basis of compatibility or dispersibility of TPs in polymer matrices are performed. The simulations show that bare TPs tend to form clusters in the matrix of excess polymers. The clustering is significantly reduced after grafting polymer chains to the TPs, which is confirmed experimentally. Transmission electron microscopy reveals that the block copolymer‐TP mixtures (“hybrids”) show much better film qualities and TP distributions within the films when compared with the homopolymer‐TP mixtures (“blends”), representing massive aggregations and cracks in the films. This grafting‐to approach for the modification of TPs significantly improves the dispersion of the TPs in matrices of “excess” polymers up to the arm length of 100 nm. 相似文献
14.
Noise level, inner hair cell damage, audiometric features, and equal-energy hypothesis 总被引:1,自引:0,他引:1
Rabbits were exposed to 2- to 7-kHz noise either for a short duration at a high sound-pressure level (15 or 30 min at 115 dB SPL), or a long duration at a low level (512 h at 85 dB SPL). The high-level exposure produced a hearing loss in the frequency range 2-6 kHz, whereas the low-level exposure gave maximum hearing loss at 12-20 kHz. The 115-dB exposure caused significantly more damage to inner hair cells than the 85-dB exposure. The implications of the present results for evaluating audiograms, equal-energy hypothesis, risk criteria, and subjective auditory features are pointed out. 相似文献
15.
We study the maximum likelihood estimator for stochastic equations with additive fractional Brownian sheet. We use the Girsanov
transform for the the two-parameter fractional Brownian motion, as well as the Malliavin calculus and Gaussian regularity
theory.
相似文献
16.
The constitutive models for the viscoelasticity of polymers are presented for determining molecular weight distributions (MWDs) from viscosity measurements. The inversion of this model derived from control theory and melt calibration procedure connects the relaxation modulus, viscosity, and other flow properties of a polymer. The linear principle enables simultaneous and accurate modelling of the relaxation modulus and of viscosity flow curves over a wide range. Starting from viscosity measurements, the new model is used to determine the MWD, linear viscoelastic relaxation moduli, and the relaxation spectra of polyethylene of different grades. In addition, two benchmark analyses of bimodal polystyrene are reported, and the capability of the model is proven by the two-box test of Malkin. The error of the modelled viscosity is smaller than that for previously reported models. One of the main features of this work is that no relaxation time or spectrum procedures were used to generate and model linear viscoelasticity. 相似文献
17.
In this paper we give a framework for applying Katona’s cycle proof of the Erd?s–Ko–Rado theorem to other objects. We also show how this method can be realized as a result using homomorphisms of graphs. 相似文献
18.
We prove an Itô–Tanaka formula and existence of pathwise stochastic integrals for a wide class of Gaussian processes. Motivated by financial applications, we define the stochastic integrals as forward-type pathwise integrals introduced by Föllmer and as pathwise generalized Lebesgue–Stieltjes integrals introduced by Zähle. As an application, we illustrate the importance of the Itô–Tanaka formula for pricing and hedging of financial derivatives. 相似文献
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