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Meccanica - This paper presents the experimental identification of the friction force in the inerter with constant and variable inertance. The change of intertance is possible due to the...  相似文献   
53.
Theoretical calculations utilizing relativistic ZORA Hamiltonian point to the conceivable existence of an IrNO3 molecule in C3v geometry. This minimum is shown to correspond to genuine nonavalent iridium nitride trioxide, which is a neutral analogue of cationic [IrO4]+ species detected recently. Despite the presence of nitride anion, the molecule is protected by substantial barriers exceeding 200 kJ mol−1 against transformations leading, for example, to global minimum (O=)2Ir−NO, which contains metal at a lower formal oxidation state.  相似文献   
54.
In this study, we examine the feasibility and limitations of describing the motional behavior of three‐domain proteins in which the domains are linearly connected. In addition to attempting the determination of the internal and overall reorientational correlation times, we investigate the existence of correlations in the motions between the three domains. Since in linearly arranged three‐domain proteins, there are typically no experimental data that can directly report on motional correlation between the first and the third domain, we address this question by dynamics simulations. Two limiting cases occur: (1) for weak repulsive potentials and (2) when strong repulsive potentials are applied between sequential domains. The motions of the terminal domains become correlated in the case of strong interdomain repulsive potentials when these potentials do not allow the angle between the sequential domains to be smaller than about 60°. Using the model‐free (MF) and extended MF formalisms of Lipari and Szabo, we find that the motional behavior can be separated into two components; the first component represents the concerted overall motion of the three domains, and the second describes the independent component of the motion of each individual domain. We find that this division of the motional behavior of the protein is maintained only when their timescales are distinct and can be made when the angles between sequential domains remain between 60° and 160°. In this work, we identify and quantify interdomain motional correlations. © 2013 Wiley Periodicals, Inc.  相似文献   
55.
Scandium and its compounds are used in many modern industrial fields due to its unique chemical and physical properties. It is mainly recovered from residues and wastes in the production of other metals. The exploitation of the ores and wastes could contaminate water and soil creating environmental problems. This paper discusses recent developments and tendencies in scandium separation, purification and preconcentration from different wastes, residues, environmental samples as well as in the production of radiopharmaceuticals for nuclear medicine, both in the laboratory and on the industrial scale. The period reviewed here mainly includes publications that have appeared, since 2010.  相似文献   
56.
Poly (ether ether ketone) was irradiated with gamma rays or electron beam to investigate the radical process. The generated paramagnetic species were observed by electron spin resonance spectroscopy at ambient temperature and in liquid nitrogen. The effect of microwave power on saturation of the particular spectra and thermal annealing effects were determined. The following radicals were identified: radical anion, phenoxyl radical, and phenylperoxy radical. Despite the fact that the intermediates were formed as a result of backbone cleavage causing degradation, the macroscopic features were almost unaffected by irradiation up to dose of 1500 kGy.  相似文献   
57.

There exist many ways to build an orthonormal basis of \(\mathbb {R}^N\), consisting of the eigenvectors of the discrete Fourier transform (DFT). In this paper we show that there is only one such orthonormal eigenbasis of the DFT that is optimal in the sense of an appropriate uncertainty principle. Moreover, we show that these optimal eigenvectors of the DFT are direct analogues of the Hermite functions, that they also satisfy a three-term recurrence relation and that they converge to Hermite functions as N increases to infinity.

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We present a routine for calculating and producing customized/parametric femtosecond laser pulses for investigating molecular processes involving the polarization. It is applied on the ionization of NaK molecules by feedback-loop optimization using the recently introduced double-pass "serial setup" that is capable of phase, amplitude, and polarization modulation. The temporal subpulse encoding uses the parameters distance, intensity, zero order spectral phase, and polarization state.  相似文献   
60.
Nanometer‐sized metal particles constitute an unavoidable family of catalysts, combining the advantages of molecular complexes in regards to their catalytic performances and the ones of heterogeneous systems in terms of easy recycling. As part of this research, our group aims at designing well‐defined metal nanoparticles based‐catalysts, in non‐conventional media (ionic liquids or water), for various catalytic applications (hydrogenation, dehalogenation, carbon‐carbon coupling, asymmetric catalysis) in mild reaction conditions. In the drive towards a more eco‐responsible chemistry, the main focuses rely on the search of highly active and selective nanocatalysts, in association with an efficient recycling mainly under pure biphasic liquid‐liquid conditions. In this Personal Account, we proposed our almost fifteen‐years odyssey in the world of metal nanoparticles for a sustainable catalysis.

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