Particle concept

The pile of solid particles concept is useful for either consolidated or unconsolidated media as a basis for analyzing the flow process, because many consolidated media are actually made up of individual particles that... 

The Wave and Particle Concepts of a Light Beam A. The Individual Photon... 

At this point it is appropriate to return to the general wave and particle concepts of light. To be more specific, we can ask whether an individual photon can be treated both as a plane wave and as a particle, and whether a broad light beam can be considered both as a stream of individual photon particles and as a plane wave. For a closer examination of these questions it becomes necessary to investigate every particular case with respect to the following points ... 

Rarey, M., Kramer, B., and Lengauer, T. (1999) The particle concept placing discrete water molecules during protein-ligand docking predictions. Proteins 34,17-28. 

Derive the expressions in the context of quasi-particles concept for the rates of adsorption and desorption of dissociating molecules on the (111) face with z — 6. Compare expressions found with the general formulas of Section 3. 

The student is first introduced to the wave and particle concepts of light. Though minimal emphasis is placed on mathematical equations, the relationship between velocity, wavelength and frequency, as well as the correlation of energy to frequency, is described. Those regions of the electromagnetic spectrum that are most useful and convenient for characterizing chemical substances are emphasized. 

The group velocity of de Broglie matter waves are seen to be identical with particle velocity. In this instance it is the wave model that seems not to need the particle concept. However, this result has been considered of academic interest only because of the dispersion of wave packets. Still, it cannot be accidental that wave packets have so many properties in common with quantum-mechanical particles and maybe the concept was abandoned prematurely. What it lacks is a mechanism to account for the appearance of mass, charge and spin, but this may not be an insurmountable problem. It is tempting to associate the rapidly oscillating component with the Compton wavelength and relativistic motion within the electronic wave packet. 

The Particle Concept Placing Discrete Water Molecules During Protein-Ligand Docking Predictions. 

Validity of the Molecular Orbital and Quasi-Particle Concepts... 

The orthodox and standard quantum measurement theory uses a probability density view focused on the particle conception. The physical nature of the interaction that may lead to an event (click) is not central. Generally, it is true that a click will be eliciting the quantum state, but due to external factors, a click can be related to noise or any source of systematic error (lousy detectors) from the QM viewpoint developed here such events have no direct QM-related cause see Ref. [17], The probabilities cannot be primary. They can be useful as actually they are. One thing is sure the clicks do have a cause. But causality is a concept more related to a particle description it belongs to classical physics. 

Matthews and Rhodes, Haines and Martin, Hie-stand, and Ecanow and co-workers are credited-with establishing the structured particle concept or flocculated pharmaceutical suspension. The following definitions should prove useful in avoding confusion among three closely related terms flocculation, agglomeration, and coagulation. The term aggregation can apply to all three. 

Example 11-5 Vycor (porous silica) appears to have a pore system with fewer interconnections than alumina. The pore system is monodisperse, with the somewhat unusual combination of a small mean pore radius (45 A) and a low porosity 0.31. Vycor may be much closer to an assembly of individual voids than to an assembly of particles surrounded by void spaces. Since the random-pore model is based on the assembly-of-particles concept, it is instructive to see how it applies to Vycor. Rao and Smith measured an effective diffusivity for hydrogen of 0.0029 cm /sec in Vycor. The apparatus was similar to that shown in Fig. 11-1, and data were obtained using an H2-N2 system at 25°C and 1 atm. Predict the effective diffusivity by the random-pore model. 

Children s preconcepts develop without a particle concept, hence the important matter-particle concept is divided in this book into two levels Substances and Properties (see Chap. 3) and Particle Model of Matter (see Chap. 4). 

After the vacuum was realized by the Torricelli experiments the horror vacui was hugely overthrown one could conceptualize a vacuum. Gassendi developed on that base the particle concept from a sub-microscopic point of view, and in 1649 he rehearsed Democritus idea of atoms and empty space as the only principles of nature, apart from the complete full and complete empty space nothing else can be considered [10]. After a two-thousand year interruption, scientists were finally able to embrace the Hypothesis of Discontinuity and to reconsider matter as being made up of smallest particles. 

If a student does not believe that sunrays absorb a puddle (see Sect. 2.1), he or she can then, using the particle model of matter with the idea of moving particles, successfully develop a scientific concept about the evaporation of water. There is an extension of the already established particle concept taught in lessons before - a conceptual growth appears. 

The particle concept presents fundamental advantages, but also certain difficulties to students. The common particle concept of matter associates for each pure matter a special kind of particle, mostly spheres as models e.g. one sphere for one water particle, another kind of sphere for one sugar particle, the mixture of both kinds of spheres the dissolution of sugar in water. On the other hand, one can use a generic particle term for atoms, ions and molecules one can only ascertain it from the context which particle term is discussed. 

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