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951.
In this work actin is used to illustrate connection of protein fluorescence characteristics with its structure. On one hand, it has been demonstrated what kind of information about the contribution of each tryptophan residues to the bulk fluorescence spectrum can be obtained from the special analysis of protein three-dimensional structure. On the other hand, potentials of intrinsic fluorescence for elucidation of proteins structure, dynamics and processes of folding-unfolding are shown. In particular, using this method a new essentially unfolded kinetic intermediate state of actin was detected and characterized, and the place of inactivated actin and its kinetic predecessor in the process of folding-unfolding was determined. It has been revealed that inactivated actin is not intermediate state between the native and completely unfolded states, as it has been accepted before, but a result of protein misfolding. On the basis of the obtained data a new model of actin folding-unfolding pathway has been proposed. 相似文献
952.
Results of investigations into the physical properties of a number of new nonlinear crystals are presented. The parameters of frequency converters manufactured on their basis are compared, and second-harmonic generation of CO2 lasers first excited by frequency conversion in LiInSe2, AgGa1– x
InxSe2, AgxGaxGexS2(1 + x), and Hg1–x
CdxGa2S4 crystals is investigated. The superiority of HgGa2S4, Hg1–x
CdxGa2S4, and AgGa1–x
InxSe2 over the well-known crystals has been demonstrated for frequency conversion both within the middle-IR range and from the visible range to the middle-IR range. Advantages of LiInSe2 and AgGa1–x
InxSe2 crystals are demonstrated for the direct frequency conversion of femtosecond laser radiation to the middle-IR range compared to the cascade frequency conversion and direct frequency conversion in LiInS2 crystals. 相似文献
953.
We prove new theorems on the justification of the averaging method for multifrequency oscillation systems with pulse influence at fixed times. 相似文献
954.
P. M. Larionov A. N. Malov M. M. Mandrik N. A. Maslov A. M. Orishich 《Journal of Applied Spectroscopy》2003,70(1):38-42
We investigated the laser-induced fluorescence spectra (LIF) of porcine cardiac tissues with different degrees of viability. The data obtained are compared with the results of routine histological investigations and also with the experiments performed with the use of fluorescent probes. It has been found with a high degree of reliability that the loss of the viability of the myocardium tissue leads to the alteration of its LIF spectra. This can be used for low-invasive rapid control of transplant viability in the process of its preparation and during surgery. 相似文献
955.
Lasing and discharge in mixtures of SF6 with hydrogen and hydrocarbons are investigated. If the chemical reaction is initiated by a self-sustained discharge (a generator
with both an inductive and capacitive energy storage can be used), the maximum lasing efficiency is attained at high values
of the ratio E/p (where E is the electric field intensity and p is the pressure in the mixture) if shaped electrodes and preionization of the discharge gap are employed. For the first time,
the lasing efficiency obtained in a nonchain HF laser is as high as 10% of the energy deposit and 4.5% of the stored energy
for a specific radiation energy of ≈140 J/(l atm). At high efficiencies, the emission spectrum of the nonchain HF laser significantly
broadens and cascade lasing at P(3-2) → P(2-1) → P(1-0) vibrational transitions for several rotational lines is realized. 相似文献
956.
R. M. Sardarly O. A. Samedov I. Sh. Sadykhov V. A. Aliev 《Physics of the Solid State》2003,45(6):1118-1121
The relaxor properties of Fe-doped TlInS2 crystals are investigated. It is shown that Fe-doped TlInS2 compounds exhibit all features inherent in relaxor ferroelectric materials. The temperature range of existence of the microdomain (relaxor) state and the temperature of the transition from this state to a macro-domain state are determined. 相似文献
957.
958.
Automotive disc brake squeal 总被引:3,自引:0,他引:3
Disc brake squeal remains an elusive problem in the automotive industry. Since the early 20th century, many investigators have examined the problem with experimental, analytical, and computational techniques, but there is as yet no method to completely suppress disc brake squeal. This paper provides a comprehensive review and bibliography of works on disc brake squeal. In an effort to make this review accessible to a large audience, background sections on vibrations, contact and disc brake systems are also included. 相似文献
959.
G. M. Maksimova A. L. Chuvilin E. M. Moroz V. A. Likholobov K. I. Matveev 《Kinetics and Catalysis》2004,45(6):870-878
Conditions for the preparation of stable aqueous monometallic and bimetallic colloidal solutions (sols) of noble metals (Ru, Rh, Pd, Pt, Ir, Ag, and Au) in the presence of polyoxometalates containing W, Mo, V, and Nb were found. The stability of sols against coagulation at room temperature was studied. The metal/C samples prepared by metal adsorption from sols were studied by powder X-ray diffraction analysis and transmission electron microscopy. The following factors of importance for the preparation of a stable sol are discussed: (1) the formation of a sol of a metal polyhydroxo complex stabilized by a polyoxometalate (preliminary stage) and (2) the formation of polyoxometalate-metal clusters in the course of reduction of polyhydroxo complexes.Translated from Kinetika i Kataliz, Vol. 45, No. 6, 2004, pp. 921–929.Original Russian Text Copyright © 2004 by Maksimova, Chuvilin, Moroz, Likholobov, Matveev. 相似文献
960.
M. I. Al-Jarallah Fazal-ur-Rehman F. Abu-Jarad A. Al-Shukri 《Radiation measurements》2003,36(1-6):445-448
An indoor radon survey of a total of 269 dwellings, with one dosimeter per house, distributed in four Saudi Arabian cities was carried out. The objective of this survey was to carry out indoor radon measurements of two cities in the Eastern Province, Khafji and Hafr Al-Batin and to compare this with two cities in the Western Province, Al-Madina and Taif. The survey provides additional information about indoor radon concentrations in Saudi Arabia. The results of the survey in these cities showed that the overall minimum, maximum and average radon concentration were 7,137 and 30 Bqm−3, respectively. The lowest average radon concentration (20 Bqm−3) was found in Hafr Al-Batin, while the highest average concentration was found in Khafji (40 Bqm−3). 相似文献