Internal energy dependent radiationless transitions in 1,3,5,‐C6F3H+3and C6F+6

1983 ◽  
Vol 79 (2) ◽  
pp. 658-664 ◽  
Author(s):  
G. Dujardin ◽  
S. Leach
Author(s):  
R.F. Egerton

SIGMAL is a short (∼ 100-line) Fortran program designed to rapidly compute cross-sections for L-shell ionization, particularly the partial crosssections required in quantitative electron energy-loss microanalysis. The program is based on a hydrogenic model, the L1 and L23 subshells being represented by scaled Coulombic wave functions, which allows the generalized oscillator strength (GOS) to be expressed analytically. In this basic form, the model predicts too large a cross-section at energies near to the ionization edge (see Fig. 1), due mainly to the fact that the screening effect of the atomic electrons is assumed constant over the L-shell region. This can be remedied by applying an energy-dependent correction to the GOS or to the effective nuclear charge, resulting in much closer agreement with experimental X-ray absorption data and with more sophisticated calculations (see Fig. 1 ).


Author(s):  
R. D. Sjolund ◽  
C. Y. Shih

The differentiation of phloem in plant tissue cultures offers a unique opportunity to study the development and structure of sieve elements in a manner that avoids the injury responses associated with the processing of similar elements in intact plants. Short segments of sieve elements formed in tissue cultures can be fixed intact while the longer strands occuring in whole plants must be cut into shorter lengths before processing. While iyuch controversy surrounds the question of phloem function in tissue cultures , sieve elements formed in these cultured cells are structurally similar to those of Intact plants. We are particullarly Interested In the structure of the plasma membrane and the peripheral ER in these cells because of their possible role in the energy-dependent active transport of sucrose into the sieve elements.


2020 ◽  
Vol 1 (2) ◽  
pp. 169-173
Author(s):  
Andrzej Lorkowski ◽  
Robert Jeszke

The whole world is currently struggling with one of the most disastrous pandemics to hit in modern times – Covid-19. Individual national governments, the WHO and worldwide media organisations are appealing for humanity to universally stay at home, to limit contact and to stay safe in the ongoing fight against this unseen threat. Economists are concerned about the devastating effect this will have on the markets and possible outcomes. One of the countries suffering from potential destruction of this situation is Poland. In this article we will explain how difficult internal energy transformation is, considering the long-term crisis associated with the extraction and usage of coal, the European Green Deal and current discussion on increasing the EU 2030 climate ambitions. In the face of an ongoing pandemic, the situation becomes even more challenging with each passing day.


2018 ◽  
Vol 14 (3) ◽  
pp. 5708-5733 ◽  
Author(s):  
Vyacheslav Michailovich Somsikov

The analytical review of the papers devoted to the deterministic mechanism of irreversibility (DMI) is presented. The history of solving of the irreversibility problem is briefly described. It is shown, how the DMI was found basing on the motion equation for a structured body. The structured body was given by a set of potentially interacting material points. The taking into account of the body’s structure led to the possibility of describing dissipative processes. This possibility caused by the transformation of the body’s motion energy into internal energy. It is shown, that the condition of holonomic constraints, which used for obtaining of the canonical formalisms of classical mechanics, is excluding the DMI in Hamiltonian systems. The concepts of D-entropy and evolutionary non-linearity are discussed. The connection between thermodynamics and the laws of classical mechanics is shown. Extended forms of the Lagrange, Hamilton, Liouville, and Schrödinger equations, which describe dissipative processes, are presented.


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