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81.
The direct energy transfer technique was modified and appliedto probe the relative localization of apomyoglobin A-, G- andH-helixes, which are partly protected from deuterium exchangein the equilibrium molten globule state and in the molten globule-likekinetic intermediate. The non-radiative transfer of tryptophanelectronic energy to 3-nitrotyrosine was studied in differentconformational states of apomyoglobin (native, molten globule,unfolded) and interpreted in terms of average distances betweengroups of the protein chain. The experimental data show thatthe distance between the middle of A-helix and the N-terminusof G-helix as well as the distance between the middle of theA-helix and the C-terminus of the H-helix in the molten globulestate are close to those in the native state. This is a strongargument in favor of similarity of the overall architectureof the molten globule and native states.  相似文献   
82.
This paper proposes the Meissner-Ochsenfeld effect as a possible tool for quality control of type II superconductors (SC). Visual or optical inspection of the levitation process allows rough determination of the anisotropy of thermal conductivity and of the pinning strength of type II SC material, in a materials quality control. An assembly of permanent (e.g. NdFeB) or electromagnets and a flat cryostat allowing visual or optical inspection would be required. The method is demonstrated by numerically simulating the field cooling process of a superconducting cylindrical pellet and of a coated conductor.  相似文献   
83.
Abstract

The oil generating potential of Domanic rocks from Dankov–Lebedyan horizon of the Zelenogorsk area of Romashkino oil field was evaluated by Rock-Eval pyrolysis technique. The result of given method depends on the content, composition, and thermal stability of organic matter in rocks. During hydrothermal processes, the distinctive conversion behavior of organic matter at temperatures of 200°С, 250°С, 300°С, and 350°С in CO2 environment was revealed. The yield of obtained aquathermolysis products and their quality were evaluated. The results of the studies suggest that low-permeability carbonate rocks of the Dankov–Lebedyan horizon contain productive beds with content of Corg 1.89–3.03%, which when developed using thermal methods, can become an additional source of liquid hydrocarbons.  相似文献   
84.
We present results from the shape optimization of linked bodies for drag reduction in simulations of incompressible flow at moderate Reynolds numbers. The optimization relies on the covariance matrix adaptation evolution strategy (CMA-ES) and the flow simulations use vortex methods with the Brinkman penalization to enforce boundary conditions in complex bodies. We exploit the inherent parallelism of CMA-ES, by implementing a multi-host framework which allows for the distribution of the expensive cost function evaluations across parallel architectures, without being limited to one computing facility. This study repeats in silico for the first time Ingo Rechenberg’s pioneering wind tunnel experiments for drag reduction that led to the inception of evolution strategies. The simulations confirm that the results of these experimental studies indicate a flat plate is not the optimal solution for drag reduction in linked bodies. We present the vorticity field of the flow and identify the governing mechanisms for this drag reduction by the slightly corrugated linked plate configuration.  相似文献   
85.
86.
The method of the solution problem on the eigen oscillations spectrum of electromagnetic field in the waveguide-dielectric resonator with the two-layer dielectric element was presented. The numerical calculations of the resonance frequencies for theHE 111-,E 011- andH 011-oscillations types in the investigated structure were performed. The calculation results were correlated with experimental data.  相似文献   
87.
88.
The key factor determining nucleation processes and faceting in homoepitaxial growth as well as texture competition is the mobility of adatoms and small clusters across step edges and facets. Using a combination of molecular dynamics and ab initio calculations, we investigate the mechanisms of small clusters (dimer and trimer) diffusion down the aluminum (1 1 1) surface. In this paper we report results of molecular dynamics studies. Our study shows that the clusters dissociate at the step-edge of compact islands. As a result, the clusters diffuse down the step by an exchange mechanism with a small or medium Schwoebel barrier. The mechanism of this down-diffusion/dissociation is discussed and the corresponding energetics are calculated using the molecular statics method. We find a large anisotropy between the barriers at the two types of 1 1 0 oriented steps.  相似文献   
89.
In this paper the exact vibration frequencies of generally laminated beams are found using a new method, including the effect of rotary inertia and shear deformations. The effect of shear in laminated beams is more significant than in homogenous beams, due to the fact that the ratio of extensional stiffness to the transverse shear stiffness is high. The exact dynamic stiffness matrix is derived, and then any set of boundary conditions including elastic connections, and assembly of members, can be solved as in the classical direct stiffness method for framed structures. The natural frequencies of vibration of a structure are those values of frequency that cause the dynamic stiffness matrix to become singular, and one can find as many frequencies as needed from the same matrix. In the paper several examples are given, and compared with results from the literature.  相似文献   
90.
In this paper Ru-containing catalysts based on hypercrosslinked polystyrene (MN-270) and its functional analogues (MN-100 and MN-500) were studied for the first time in cellulose hydrolytic hydrogenation. The catalysts were characterized using transmission electron microscopy (TEM), high resolution TEM, and porosity measurements. Catalytic studies demonstrated that the catalyst containing 1.0 % Ru and based on MN-270 is the most active. The total yield of sorbitol and mannitol was 50 % on the average at 85 % cellulose conversion.  相似文献   
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