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951.
N. G. Basov V. F. Belyan G. P. Zhilkin V. S. Zvezdin V. S. Krasovskii O. N. Krokhin B. V. Kruglov A. V. Kutsenko Yu. N. Ol'shevskii N. V. Pletnev Yu. V. Senat-skii G. V. Sklizkov L. K. Subbotin S. I. Fedotov N. N. Shermet'evskii 《Journal of Russian Laser Research》1980,1(1):38-62
The concrete object of the investigation is the alignment of the high-power 12-channel Del'fin neodymium-glass laser facility. The objects of the alignment are the optical channel of the laser installation, the system for pointing and focusing the laser radiation on the target, the system for positioning the target in the focal volume, and the system for monitoring the optical quality of the elements of the laser installation and laser beams and also the conditions of the target irradiation in the vacuum chamber. The list of requirements that must be satisfied by the alignment beams, the possible sources of alignment beams, the makeup of the apparatus, and the methods of aligning the laser facility are considered. The principles and the actual systems of automatic alignment of the optical elements are described, as are the operating models of the automatized units. The problem of simulating the working laser beams by the alignment beams and the possibility of automatizing the control of the spatial and angular characteristics of the laser radiation are discussed. The system for controlling the alignment processes by means of a laser is considered, as is also a scheme for incorporating the automatized alignment subsystem in the overall system for the automation of the Del'fln facility.Translated from Trudy Ordena Lenina Fizicheskogo Instituta im. P. N. Lebedeva, Vol. 103, pp. 52–83, 1978. 相似文献
952.
O. P. Vinogradov 《Mathematical Notes》1977,22(4):809-811
A class of weakly aging distribution functions is introduced and a number of properties of this class are derived. It is proved in particular that a random variable , having a weakly aging distribution function, can be written as a sum of two independent random variables, one of which has exponential distribution with a parameter equal to the modulus of the singular point of Me–s nearest the coordinate origin.Translated from Matematicheskie Zametki, Vol. 22, No. 4, pp. 571–574, October, 1977. 相似文献
953.
954.
In [1], a set of convergent and stable two-point formulae for obtaining the numerical solution of ordinary differential equations having oscillatory solutions was formulated. The derivation of these formulae was based on a non-polynomial interpolant which required the prior analytic evaluation of the higher order derivatives of the system before proceeding to the solution. In this paper, we present a linear multistep scheme of order four which circumvents this (often tedious) initial preparation. The necessary starting values for the integration scheme are generated by an adaptation of the variable order Gragg-Bulirsch-Stoer algorithm as formulated in [2]. 相似文献
955.
The equations governing geometrical objects in ? space are written in terms of operators adapted to families of left shear-freeσ 0= 0) cross sections of complexified null infinity (C I +). The concept of ?-conformai weight (HCW) is introduced, and a derivative operatorI a ′ , which is closely connected with the covariant derivative but which (unlike the covariant derivative) maps objects having well-defined HCW to other such objects, is defined. A function ?, derived from the Gaussian curvature of left shear-free slicings ofC I + and having a well-defined HCW, is shown to contain all the curvature information for ? space. 相似文献
956.
The internal conversion coefficients were calculated for the 165.853 keV 5/2+7/2+ hindered transition in
57
139
La using the new computer program NICC for conversion coefficients of all atomic shells. The algorithm employed in this code is described. The analysis of precise experimental data yielded the nuclear penetration parameter=4.2±0.8. This value was found to be in accord with theoretical estimates and to correspond to the Nilsson deformation parameter=–0.056±0004 of the139La nucleus. Using the Nilsson wave functions for above the mixing ratio
2 = N(E2)/N(M1) was determined to be less than 8.10–5, which supports the assumption of a pureM1 multipolarity of this transition.Presented at the 26th All-Union Conference on Nuclear Spectroscopy and Nuclear Structure (February 1976, Baku, USSR).We are obliged to Dr. B. N.Subba Rao for the communication of his value for the investigated transition. 相似文献
957.
G. Zech F. Dydak F.L. Navarria O.E. Overseth P. Steffen H. Wahl E.G.H. Williams C. Geweniger K. Kleinknecht H. Taureg 《Nuclear Physics B》1977,124(4):413-425
The mean lifetimes of the Λ and Ξ0 hyperons have been measured in a short neutral beam at the CERN Proton Synchrotron. Λ and Ξ0 decays have been identified by measuring their decay products in a magnetic spectrometer and in a lead glass hodoscope. The experimental results, based on 53 000 Λ decays and 6300 Ξ0 decays are From the result for τΞ0 together with existing data on τΞ? we obtain a violation of the rule in non-leptonic Ξ decays. 相似文献
958.
M. S. Bryant J. O. Lay M. P. Chiarelli 《Journal of the American Society for Mass Spectrometry》1992,3(4):360-371
An analytical strategy using fast atom bombardment (FAB) ionization and tandem mass spectrometry has been developed to determine the molecular weight and major fragment ions, and to provide limited structural characterization of low picomole levels of carcinogen-nucleoside adducts. This strategy consists of three main components: (1) the sensitivity for analysis by FAB combined with mass spectrometry is increased via chemical derivatization; (2) the nucleoside adducts are selectively detected by using constant neutral loss scans; and (3) structurally characteristic fragments are obtained by using daughter ion scans. Trimethylsilyl derivatized arylamine-nucleoside adducts have been detected at levels as low as a few picomoles by using this approach. After experimental determination of the mass of the BH 2 + fragment ion, daughter ion spectra have been used to probe the structure specificity associated with collision-activated decomposition of this fragment. With model C-8 substituted arylamine adducts [N-(deoxyguanosin-8-yl)-4-aminobiphenyl, N-(deoxyadenosin--yl)-4-aminobiphenyl, and N-(deoxyguanosin-8-yl)-2-aminofluorene], nucleoside-specific and carcinogen-specific fragmentation have been observed in daughter ion spectra. 相似文献
959.
O. V. Gusev M. A. Ievlev M. G. Peterleitner S. M. Peregudova L. I. Denisovich P. V. Petrovskii N. A. Ustynyuk 《Russian Chemical Bulletin》1996,45(7):1601-1607
A series of are necyc lope ntadienyl complexes,i. e., [Ru(5-c5R5)(6- are ne)]+ (1, R= H, arene = C6H6; 2, R = Me, arme = C6H6; 3, R = H, arctic = C6H3Me3; 4, R = Me, arene = C6H3Me3; 5, R = H, arene = C6Me6; 6, R = Me, arene = C6Me6) was studied by cyclic voltammetry. These compounds are capable of both oxidation and reduction. The reduction potential values depend on the number of methyl groups in the complex. Reduction of benzene complexes I and 2 by sodium amalgam in THF leads to the formation of decomplexation products, the addition of hydrogen to benzene, and dimerization of the benzene ligands. Both chemical and electrochemical reductions of mesitylene complexes3 and4 result in dimeric products [(5-C5R5)Ru(-5;5-Me3H3C6H3Me3)Ru(5-C5R5)] (14, R = H; 15, R = Me). The action of sodium amalgam on compound5 gives products of hydrogen addition to both hexamethylbenzene (17) and cyclopentadienyl (18) ligands along with the major product, the dimer [5-C5H5)Ru(-5; 5-Me6C6C6Me6)Ru(5-C5H5)] (16). In contrast to5, its permcthylated analog 6 is only capable of adding hydrogen to the hexamethylbenzene ligand.Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 7, pp. 1691–1697, July, 1996. 相似文献
960.
The amperometric detection of some organic sulphides in non-aqueous media using a horseradish peroxidase modified platinum electrode is reported. The performance of the electrode is based on the inhibitory effect of sulphides on the activity of peroxidase. The electrode responds rapidly to micromolar concentrations of the sulphides with linearities extending up to 0.4, 0.25 and 0.8 mmol/dm(3) for thiourea, ethylenethiourea, and mercaptoethanol, respectively. The current as peroxide concentration approaches infinity in the absence of any inhibitor (I(max)), and the apparent inhibition constant (K'(i)) for each inhibitor were evaluated. I(max)/K'(i), i.e. the percentage inhibition of sensor response per millimolar of each inhibitor, was calculated and used as a measure of the performance of the sensor in the determination of the organic sulphides. From these values the sensitivity trend of the biosensor for the organic sulphides is ethylenethiourea > thiourea > mercaptoethanol. The kinetic effects of other operational parameters such as mediator concentration, water content of the solvent and working potential were also evaluated to assess analytical performance. 相似文献