Corpuscular description

The interaction of ionizing electromagnetic radiation with matter is different from the processes previously mentioned, and the concept of ranges and specific ionization loss cannot be applied. Only the three most important absorption processes are considered the photoelectric effect, the Compton effect, and the pair-production effect. The corpuscular description of electromagnetic radiation is the most appropriate for these effects, as one photon in a well-collimated beam of photons disappears at each interaction. The attenuation of the photon beam can be described by a simple exponential law... 

In the first case, corpuscular description, the energy of the photons is... 

The relation (2) can also be obtained by solving the 3s-dlmenslonal dynamical equations of motion of a harmonic lattice and are thereby identified as the normal modes of vibrations of the lattice. As is the case in electromagnetic displacements, it is often convenient to replace the normal modes by an equivalent corpuscular description of the lattice displacements. As a result it is usual to associate a phonon with each of the normal modes. 

The first consistent attempt to unify quantum theory and relativity came after Schrddinger s and Heisenberg s work in 1925 and 1926 produced the rules for the quantum mechanical description of nonrelativistic systems of point particles. Mention should be made of the fact that in these developments de Broglie s hypothesis attributing wave-corpuscular properties to all matter played an important role. Central to this hypothesis are the relations between particle and wave properties E — hv and p = Ilk, which de Broglie advanced on the basis of relativistic dynamics. 

To further elaborate on this last point, it should be noted that once corpuscular theory is introduced it should provide students with meaningful descriptions, explanations and predictions of macroscopic phenomena and relationships in terms of sub-microscopic entities such as atoms, molecules and electrons. But, alas, according to the foram of experts in chemical education, it does not (Van Berkel et al., 2000). Not only students, but also teachers as well as textbook writers make mistakes with regard to the macro/sub-micro/symbolic levels. Here are some examples mentioned by the international and Dutch fomm. 

Voronoi-Delaunay Method for Description of Corpuscular and Sponge-Like Porous Solids... 

The law at which we have arrived (which is merely a description of the appearances, and involves, I believe, nothing hypothetic), is certainly not provided for in the corpuscular philosophy of the day, and is altogether so extraordinary, that I may be excused for not speculating further upon its cause, till its various bearings, and certain collateral subjects, be fully investigated. 

The possibility that the propagation of fight could have a dual nature arose in the seventeenth century as a controversy between Newton and Huygens corpuscular versus undulatory descriptions, respectively. When Maxwell s electromagnetic theory was developed in the nineteenth century, the matter seemed settled in favor of the proponents of wave-like electromagnetic phenomena. 

The parameters of the pore structure, such as surface area, pore volume, and mean pore diameter, can generally be used for a formal description of the porous systems, irrespective of their chemical composition and their origin, and for a more detailed study of the pore formation mechanism, the geometric aspects of pore structure are important. This picture, however, oversimplifies the situation because it provides a pore uniformity that is far from reality. Thorough attempts have been made to achieve the mathematical description of porous matter. Researchers discussed the cause of porosity in various materials and concluded that there are two main types of material based on pore structure that can be classified as corpuscular and spongy systems. In the case of the silica matrices obtained with TEOS and other precursors, the porous structure seems to be of the corpuscular type, in which the pores consist of the interstices between discrete particles of the solid material. In such a system, the pore structure depends on the pores mutual arrangements, and the dimensions of the pores are controlled by the size of the interparticle volumes (1). 

Equation (1.5) establishes a bridge between a description of fight as an (electromagnetic) wave of frequency v and as a beam of -q energy particles. If phenomena related to time averages, such as diffraction and interference, can be easily interpreted in terms of waves, other phenomena, involving a one-to-one relation such as the photoelectric and the Compton effects, require a description based on corpuscular attributes. This wave-particle duality reflects the use of one or the other description depending on the experiment performed, while no experiment exists which exhibits both aspects of the duality simultaneously. 

Bohr had calculated the most accurately known experimental constant in physics by a method which was, to use a mild description, simply an outrage The corpuscular nature of light had come to stay it could no longer be ignored. No evangelist ever made so many converts in so short a time as did Bohr. 

In order to develop structured models for the description of growth and product formation of cultured plant cells, knowledge of the pathways of primary and secondary metabolism is essential. This knowledge is still limited, however, especially with respect to secondary metabolism. Corpuscular models are not common in process development. It is interesting, however, to realize that corpuscular models of the type developed by de Gunst et al. (160-162) do offer the possibility of describing cell differentiation. 

W. T. Astbury, Kolloid-Z., 83 (1938), 130, see p. 135 proposed to replace the originally used description of the native proteins as globular by corpuscular since the tightly built kinetic units are often not isodiametrically dimensioned, indeed are sometimes even considerably extended in one direction, for example in some virus proteins. 

There are nevertheless regularities in chemical description and explanation, one of them being that the extensive variable is, contrary to the use in physics, not mass but amount of substance (which is in fact coherent with the dominance of a corpuscular epistemology in the field). 

Porous solids of various origins are of various and complex morphology (ref. 1). Their structure is corpuscular (ensembles of particles) or spongy (labyrinth of shannels and cavities). Modelling of these complex systems is necessary for theoretical description and Interpretation of their geometrical, sorption, diffusion, mechanical, thermal and electrical properties (ref. 2). 

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