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881.
882.
We propose objectives consisting of two mirrors with central holes for passage of a light beam. The optical layout ensures
multiple reflection of rays from both mirrors. We consider several approaches to calculating the design parameters for which
three and four aberrations do not occur. The objectives can be used in optical devices operating in the UV and IR regions
of the spectrum.
__________
Translated from Zhurnal Prikladnoi Spektroskopii, Vol. 74, No. 2, pp. 267–270, March–April, 2007. 相似文献
883.
A. V. Porfir’eva G. A. Evtyugin E. Yu. Podshivalina L. I. Anchikova G. K. Budnikov 《Journal of Analytical Chemistry》2007,62(12):1180-1186
A new technique is proposed for detecting interactions between DNA and DNA autoimmune antibodies using a potentiometric sensor based on a glassy-carbon electrode modified with polyaniline and native DNA from chicken erythrocytes. It is shown that the DNA-antibody interaction changes the rate of polyaniline doping in transferring the DNA sensor from an alkaline (pH 7.5) solution, which is optimum for the immunochemical reaction, to an acidic (pH 3.0) solution. The dynamics of the variation of the DNA sensor potential depends on the titer of antibodies and their origin. The dependence of the DNA sensor signal on the dilution of the blood sera from systemic lupus erythematosus and autoimmune thyroiditis patients shows that DNA antibodies can be diagnosed by the characteristic maximum in the dilution curve found in the range of serum dilutions from 1: 20 to 1: 50. 相似文献
884.
E. S. Voropai M. P. Samtsov K. N. Kaplevskii A. A. Maskevich V. I. Stepuro O. I. Povarova I. M. Kuznetsova K. K. Turoverov A. L. Fink V. N. Uverskii 《Journal of Applied Spectroscopy》2003,70(6):868-874
Comparative analysis of the absorption and fluorescence spectra and fluorescence excitation spectra of thioflavin T (ThT) in various solvents and in the composition of amyloid fibrils has shown that ThT, when excited in the region of the long-wavelength absorption band, fluoresces in the spectral region with a maximum at 478–484 nm. The appearance in aqueous and alcohol solutions of a fluorescence band with a maximum near 440 nm has been attributed to the presence in the composition of the ThT preparations of an impurity with an absorption band in the 340–350-nm range. The literature data showing that in glycerol ThT has a wide fluorescence spectrum with two maxima are due to the artifact connected with the use of a high concentration of the dye. It has been suggested that the cause of the low quantum yield of ThT aqueous and alcohol solutions is the breakage of the system of conjugated bonds due to the reorientation of the benzothiozole and benzaminic rings of ThT in the excited state with respect to one another. The main factor determining the high quantum yield of fluorescence of ThT incorporated in fibrils is the steric restriction of the rotation of the rings about one another under these conditions. The suggestions made have been verified by the quantum-chemical calculation of the ThT molecule geometry in the ground and excited states. 相似文献
885.
886.
887.
888.
K. Olimov K. G. Gulamov V. V. Lugovoi S. L. Lutpullaev Kh. K. Olimov V. I. Petrov 《Physics of Atomic Nuclei》2007,70(11):1977-1979
889.
文章讨论无界区域上GBBM方程的Cauchy问题,对方程的解进行了先验估计,并证明了在H1弱拓扑中整体吸引子的存在性. 相似文献
890.