Collective field observable quantities

Closed or open systems on the macroscopic level turn out to be characterized by relatively few collective macroscopic observable quantities, also denoted here as grossvariables or macrovariables. Examples are pressure, density entropy, energy- and particle-fluxes, correlation functions and further parameters characterizing the macroscopic state or dynamic space-time structure of fields and particles. 

The procedure of Lifson and Warshel leads to so-called consistent force fields (OFF) and operates as follows First a set of reliable experimental data, as many as possible (or feasible), is collected from a large set of molecules which belong to a family of molecules of interest. These data comprise, for instance, vibrational properties (Section 3.3.), structural quantities, thermochemical measurements, and crystal properties (heats of sublimation, lattice constants, lattice vibrations). We restrict our discussion to the first three kinds of experimental observation. All data used for the optimisation process are calculated and the differences between observed and calculated quantities evaluated. Subsequently the sum of the squares of these differences is minimised in an iterative process under variation of the potential constants. The ultimately resulting values for the potential constants are the best possible within the data set and analytical form of the chosen force field. Starting values of the potential constants for the least-squares process can be derived from the same sources as mentioned in connection with trial-and-error procedures. 

Analyses of ambient air samples have thus far failed to detect the presence of sulfuric acid. However, considerable quantities of ammonium sulfate salts have been detected. One possible explanation is that sulfuric acid aerosol trapped on a filter is converted to ammonium salts by reaction with ammonia in the air pulled through the filter. A laboratory generated sulfuric acid aerosol collected on a Fluoropore filter was placed in a filter holder. Arbitrarily selected suburban and urban air was passed through the filter at a rate or 30 liters/minute for approximately one hour. In every case > 95% of the sulfuric acid was apparently converted to ammonium salts of sulfate. A strict material balance was not performed. A blank sample of laboratory generated sulfuric acid aerosols was transported to and from the field with proper precautions. Less than 5% conversion of the sulfuric acid to ammonium sulfate was observed for this sample. 

United States, permits are often mandatory for plant collections made within city, county, state, and national parks, as well as for those made in wilderness areas, conservancies, and other protected sites. Such permits are usually specific as to species and quantity of material allowed for collection and expire within 6 to 12 months. Many require submitting a detailed proposal, depositing a set of herbarium specimens, and presenting periodic field or progress reports (personal observation).23... 

Besides the basic interest in atomic quantities, the values of transition probabilities are used in different fields of research and technology astrophysics, atmospheric physics, plasma physics, thermonuclear-fusion research and development of laser systems. The evaluation of atomic concentrations can frequently be performed from observed light intensities, when direct concentration measurements are not possible. A large data compilation has been performed at NIST [10-13]. Presently, a great part of the data collection and systematization is performed for astrophysical needs within the international Opacity Project and the Iron Project [14,15]. Since 1990, when the Goddard High-Resolution Spectrograph on the Hubble Space Telescope started to work, the demand for transition probabilities for VUV spectral lines dramatically increased [16,17]. 

Endless quantities of the information which are collected in everyday life are presented to the mankind in the visual form, using various presentation devices. Seeing is a believing is the motto of the unidentified flying object (UFO) observers, which could be used for all other areas of the high-level observations. Contemporary research is based on the detection of variations in the electromagnetic spectmm or interactions between fields or particles in the open systems, which are then presented in the visual form. Figure 13.23 presents the time-space scale and the visualization devices which are used to obtain the information. 

The wave function is a quantity, which is analogous to the wave amplitude of a light field. Its absolute square is identified with an observed intensity after collecting a huge number of electrons on a screen. In particular, the interference pattern in a double slit experiment with electrons is obtained by superimposing two waves originating from two slits at the positions on a remote screen (Fig. 6.2). At a long distance from the source both spherical and cylinder waves (circular holes or slits) can be approximated by plane waves. At the observation point on the remote screen, the superposition of the two wave functions thus yields. 

Analysis of a bacteria population in ambient air. The technique consists in first collecting the bacteria in a small dish, then cracking them open by means of an electric field, and finally transferring their DNA to a series of reactors, each of which contains a segment of DNA specific to a particular bacterium. If the DNA under test matches any of the references, recombination occurs, which can be observed by fluorescence methods. Everything must be done on a small scale to limit the quantities of material needed and the analysis time. 

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