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81.
B. F. Parsons K. E. Strecker D. W. Chandler 《The European Physical Journal D - Atomic, Molecular, Optical and Plasma Physics》2006,38(1):15-20
In our previous work we investigated electronically non-adiabatic effects in
using crossed molecular beam scattering
coupled with velocity mapped ion imaging. The prior experiments placed
limits on the cross-section for electronically non-adiabatic spin-orbit
excitation
and electronically non-adiabatic spin-orbit
quenching
.
In the present work, we investigate
electronically non-adiabatic spin-orbit quenching for
which is the required first step for the
reaction of Cl* to produce ground state HCl+H products. In these
experiments we collide Cl (2P) with H2 at a series of fixed
collision energies using a crossed molecular beam machine with velocity
mapped ion imaging detection. Through an analysis of our ion images, we
determine the fraction of electronically adiabatic scattering in
Cl* +H2, which allows us to place limits on the cross-section for
electronically non-adiabatic scattering or quenching. We determine the following
quenching cross-sections σ quench(2.1 kcal/mol) = 26 ±
21 ?2, σ quench(4.0 kcal/mol) = 21 ±
49 ?2, and σ quench(5.6 kcal/mol) = 14 ±
41 ?2. 相似文献
82.
C. M. Sands H. W. Chandler I. A. Guz Y. A. Zhuk 《Archive of Applied Mechanics (Ingenieur Archiv)》2010,80(2):161-173
This paper demonstrates that, at extreme levels of kinematic hardening, the traditional formulation of the Bodner–Partom model
can produce anomalous results. The reasons for this anomalous behaviour are explained, and a reformulated version of the model
is presented. This reformulation extends the range of the model to include levels of kinematic hardening that may be problematic
in the traditional formulation. The formulation of the model is adjusted so as to retain the rate dependency of the original
Bodner–Partom model; and to permit the values of the material parameters used with the traditional formulation to be re-used
with the extended model—with the exception only of the hardening coefficients which become dimensionless constants holding
different numerical values. This revised formulation also imposes associated flow, thereby ensuring phase consistency between
stress and plastic strain during non-proportional loading. In this way, the anomalies are removed, the range and stability
of the model is increased, and all the advantages and important features of the Bodner–Partom model are retained. 相似文献
83.
84.
85.
Seven mathematics textbook series used for Grades 1 through 8 were examined. Textbook pages were counted as arithmetic, measurement, geometry, data analysis, or algebra. Percentages of mathematics textbook content were compared with percentages of mathematics content on the Ohio Ninth Grade Proficiency Test. Areas of greatest mismatch were arithmetic, measurement, and algebra. The overall percentage of arithmetic in the textbook series was about twice that on the test; the percentage of measurement was less than half that on the test; and the percentage of algebra was a third or less than that on the test. Results are also presented by grade level, and implications for teaching are discussed. 相似文献
86.
87.
Philip P. Chandler 《Historia Mathematica》1977,4(4)
An analysis of Newton's theory of the lunar apsidal motion in the Principia shows an inadequacy for which he attempted to compensate by adjusting his numerical assumptions. 相似文献
88.
Chandler Davis 《Linear algebra and its applications》1977,18(1):33-43
Problem: Given operators Aj ? O on Hilbert space , with ΣAj = 1, to find commuting projectors Ej on a Hilbert space ? such that (for all j) x1Ajy = x1Ejy for, x, y ∈ . This paper gives an explicit construction, quite different from the familiar solution. 相似文献
89.
Unrestricted and restricted Hartree-Fock calculations for the tetrachlorocobaltate(II) ion ICoCl42?) are presented. The spin density distributions from these calculations are compared with polarized neutron diffraction results through spin density plots and a population analysis. 相似文献
90.
F. L. Tobiason Laurence Huestis Chris Chandler Svend E. Pedersen Phillip Peters 《Journal of heterocyclic chemistry》1973,10(5):773-778
Permanent electric dipole moments have been determined in benzene solutions at 25° for the oxygen, sulfur, and selenium series of 2,1,3-benzodiazoles. The derivatives studied contained 4, 5, and 6 substituted methyl, chloro, nitro, and amino groups. The dipole moment data of the derivatives were analyzed relative to that of the parent species which allowed deductions to be made about the mesomeric structures operating in the compounds. The mesomeric charge transfer increases regularly from the oxygen to the selenium structures, being nearly undetected in 2,1,3-benzoxadiazole derivatives and very pronounced in the 2,1,3-benzoselenadiazoles. 相似文献