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991.
A. E. Kramida M.-C. Buchet-Poulizac 《The European Physical Journal D - Atomic, Molecular, Optical and Plasma Physics》2006,39(2):173-188
All experimental data on the
valence-shell-excited and core-excited spectra of Li-like neon, including
previously unpublished beam-foil spectroscopy data, have been compiled and
critically evaluated. Seventeen spectral lines have been newly identified.
Sets of recommended energy levels have been derived from the total list of
observed lines and from selected results of theoretical and semi-empirical
calculations. An accurate value of the ionization potential has been derived
from existing theoretical calculations.
Electronic supplementary material Online Material 相似文献
992.
T. V. Baikova M. L. Gubkina A. V. Larin K. M. Nikolaev N. S. Polyakov 《Russian Chemical Bulletin》1993,42(9):1477-1479
The adsorption behavior of Vulkan-7H carbon black graphitized at 3073 K was studied. Benzene adsorption isotherms at 293 K were measured by the static method and by gas chromatography. It was shown that Vulkan-7H carbon black may be considered as a supermicroporous adsorbent with a pore size of 1.05 nm.The sample was provided by N. N. Lezhnev.Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 9, pp. 1544–1546, September, 1993. 相似文献
993.
E. N. Yurchenko V. Yu. Prokofev A. P. Ilyin Yu. G. Shyrokov 《Reaction Kinetics and Catalysis Letters》1997,60(2):269-277
Structure-mechanical and rheological characteristics of pastes on the basis of TiO2 and Al2O3 are discussed. Optinum values to prepare honeycomb supports are determined. 相似文献
994.
R. P. Tye R. L. Gardner A. Maesono 《Journal of Thermal Analysis and Calorimetry》1993,40(3):1009-1016
Several factors in temperature measurement that can affect the precision of melting points and phase-change phenomena are discussed. In many cases, critical errors may arise in the measurement and control of temperatures due to incorrect placement and/or interpretation of the output of temperature sensors in the various system types that are in current use. Advantages can be obtained by using one temperature sensor only for temperature measurement and temperature control in a low mass infrared gold image fumace for the analytical studies in both the constant rate and stepwise isothermal thermoanalytical heating and cooling modes. Illustrations of the use of this instrumentation for measurements in both modes are given. 相似文献
995.
Let Γ denote a distance-regular graph with diameter d≥3. By a parallelogram of length 3, we mean a 4-tuple xyzw consisting of vertices of Γ such that ∂(x,y)=∂(z,w)=1, ∂(x,z)=3, and ∂(x,w)=∂(y,w)=∂(y,z)=2, where ∂ denotes the path-length distance function. Assume that Γ has intersection numbers a
1=0 and a
2≠0. We prove that the following (i) and (ii) are equivalent. (i) Γ is Q-polynomial and contains no parallelograms of length 3; (ii) Γ has classical parameters (d,b,α,β) with b<−1. Furthermore, suppose that (i) and (ii) hold. We show that each of b(b+1)2(b+2)/c
2, (b−2)(b−1)b(b+1)/(2+2b−c
2) is an integer and that c
2≤b(b+1). This upper bound for c
2 is optimal, since the Hermitian forms graph Her2(d) is a triangle-free distance-regular graph that satisfies c
2=b(b+1).
Work partially supported by the National Science Council of Taiwan, R.O.C. 相似文献
996.
G.Rezaei Behbehani A.A.Saboury M.Mohebbian S.Tahmasbi Sarvestani M.Poorheravi 《中国化学快报》2009,20(11):1389-1392
Cyanide ion was studied as an inhibitor of Jack bean urease at 300 K in 30 mmol/L tris buffer,pH 7.The inhibition was investigated by isothermal titration calorimetry(ITC).The extended solvation model was used for CN~- + JBU interaction over the whole range of CN~- concentrations.The binding parameters recovered from the solvation model were attributed to the cyanide ion interaction.It was found that cyanide ion acted as a non-cooperative inhibitor of urease,and there is a set of 12±0.12 identical and in... 相似文献
997.
In this article, the interaction of formaldehyde (FA) with thymine is theoretically investigated by computational chemistry
methods. The optimization geometries and vibrational frequencies of FA, thymine and three complexes between thymine and FA
have been calculated by using the density functional theory and ab initio methods at the B3LYP/6-311G(d, p) and MP2/6-311G(d,
p) levels. The NBO and AIM methods are used to analyse interaction as well. Conformers (A), (B) and (C) are cyclic structures
with C–H***O and N–H***O hydrogen bonds on a common plane. The corrected complex interaction energies of cyclic structures
(A), (B) and (C) at MP2/6-311G(d, p) levels are −38.41, −26.94 and −26.01 kJ/mol, respectively. The order of stability is
(A) > (B) > (C). 相似文献
998.
P. Saavedra C. N. Hernández I. Luengo J. Artiles A. Santana 《Computational Statistics》2008,23(1):79-98
A set of time series generated by stationary linear processes with an absolutely continuous spectral distribution is analysed.
The time series can then be considered realizations of a linear process of random coefficients. Likewise, each spectral density
function is a realization of a stochastic process whose function of means is called a population spectrum. We propose a kernel
estimator for the population spectrum and give conditions for its consistency. We then illustrate the properties of this estimator
in a simulation study and compare its performance with an alternative parametric estimator that can be found in the literature.
相似文献
999.
1000.
M. N. Afsar Kenneth J. Button 《International Journal of Infrared and Millimeter Waves》1982,3(6):929-939
These coolant materials were chosen for the first in this series of measrements of the complex parameters of liquids over the entire millimeter and submillimeter wavelength range of the spectrum. The fluorocarbon coolants not reported here exhibit an order of magnitude lower loss. It is the characteristic of these liquids that the absorption coefficient increases monotonically with frequency.Partially supported by the Office of Fusion Energy, U.S. Department of Energy, under Contract W-7405-eng-26 with Union Carbide Corporation.Supported by the National Science Foundation. 相似文献