Physical nature of the dielectric constant ε of H2O I. Physical processes in an ideal model

Animals make decisions based on the sensory information that they obtain from the environment and other organisms within that environment. In a river, this information is transported, transmitted, masked, and filtered by fluvial factors and processes, such as relative roughness and turbulent flow. By interpreting the resultant signals, animals decide on the suitability of habitat and their reaction to other organisms. While a great deal is known about the sensory biology of animals, only limited attention has been paid to the environmental controls on the propagation of sensory information within rivers. Here, the potential transport mechanisms and masking processes of the sensory information used by animals in gravel-bed rivers are assessed by considering how the physical nature of sensory signals are affected by river hydromorphology. In addition, the physical processes that animals have the potential to directly perceive are discussed. Understanding the environmental phenomena that animals directly perceive will substantially improve understanding of what controls animal distributions, shifting emphasis from identifying correlations between biotic and abiotic factors to a better appreciation of causation, with benefits for successful management.

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New Results on Eta Carinae. Evidence for an Asymmetric, Inhomogeneous Wind

Symposium - International Astronomical Union ◽

10.1017/s0074180900149022 ◽

1986 ◽

Vol 116 ◽

pp. 249-252

Author(s):

R. Viotti ◽

L. Rossi ◽

A. Altamore ◽

C. Rossi ◽

A. Cassatella

Keyword(s):

Physical Nature ◽

Physical Processes ◽

Physical Reason ◽

X Ray ◽

Eta Carinae ◽

Physical Conditions ◽

Astrophysical Objects ◽

Peculiar Object ◽

Light History ◽

Dust Condensation

The very peculiar object Eta Car is one of the best laboratory for the study of those physical processes - such as mass loss, superionization, dust condensation, wind interaction with the i.s. medium - that presently are of great astrophysical interest, especially for the study of the most luminous stars. For its light history and high luminosity Eta Car may also be considered as the galactic counterpart of the Hubble-Sandage variables. Eta Car is one of the rare astrophysical objects with evidence of dust condensation from ejected stellar matter (Andriesse et al. 78) On the other side the star is also producing a strong, hard X-ray flux (Chlebowski et al. 1984), and the problem is whether there is any physical reason to have these two quite different processes in the same stellar environment. In any case rather extreme physical conditions are required which cannot be verified in a uniformly, spherically symmetric atmospheric enevelope. Andriesse et al. in fact suggested the presence of strong inhomogeneities, such as filaments, possibly related to the presence of a strong magnetic field. This may also explain the X-ray emission. In the following we shall present new optical and UV observations of Eta Car and its small nebula with the aim of clearfying the physical nature of its wind.

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Philosophical tendencies in the genesis of our understanding of physical nature

Suid-Afrikaanse Tydskrif vir Natuurwetenskap en Tegnologie ◽

10.4102/satnt.v25i2.150 ◽

2006 ◽

Vol 25 (2) ◽

pp. 93-110

Author(s):

D. F. M. Strauss

Keyword(s):

World View ◽

Early Modern Period ◽

Physical Nature ◽

Physical Aspect ◽

Physical Processes ◽

Greek Culture ◽

Greek Mathematics ◽

Theoretical Thinking ◽

20Th Century Physics ◽

The Universe

The rise of a long-standing legacy of natural scientific thought is found in ancient Greece – the well-spring of Western civilization and the source of articulated rational reflection. The earliest phase of Greek culture already gave birth to theoretical thinking about the universe. The Pythagoreans are first of all famous for their emphasis on number as a mode of explanation. However, in their thesis that everything is number they solely acknowledged rational numbers (fractions) and this approach eventually stranded on the discovery of irrational numbers that led to the geometrization of Greek mathematics. This transition generated at once also a powerful space metaphysics overarching the entire medieval period. It was only during the early modern period that the predecessors and successors of Galileo contemplated an appreciation for motion as a new principle of explanation (compare the classical mechanistic world view of the universe as a mechanism of material particles in motion). But also this mechanistic reduction (through which all physical processes were reduced to the motion of charged or uncharged mass-points) eventually failed because it was unable to account for the irreversibility of physical processes. As a result it was only 20th century physics that managed to acknowledge the decisive qualifying role of energy-operation (thus of the physical aspect) in the existence of material things and processes. This article is concluded with an explanation of the significance of the preceding considerations for a theoretical approximation of the mysterious nature of matter.

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Electromagnetic sensor for measuring the dielectric permeability of materials

Visnyk of V.N. Karazin Kharkiv National University, series “Radio Physics and Electronics” ◽

10.26565/2311-0872-2020-32-06 ◽

2020 ◽

Keyword(s):

Dielectric Constant ◽

Experimental Studies ◽

Dielectric Permeability ◽

Physical Nature ◽

Diagnostic Methods ◽

Effective Dielectric Constant ◽

Original Design ◽

Microstrip Resonator ◽

Electromagnetic Sensor ◽

Electrophysical Parameters

Relevance: Problems of control and determination of electrophysical parameters of materials of different physical nature are relevant in terms of the development of express methods of analysis of substances in various fields of science and technology, in particular, in biotechnology and biomedicine. Also, the relevance of the work is grounded by the search and implementation of new non-invasive medical diagnostic methods. The purpose of the work is to experimentally test the method of calculating the dielectric constant of multilayer structures based on conformal transformation, to test the method of electromagnetic probing of objects with one-side access using a microstrip resonator. Materials and methods: The paper presents a method for calculating the effective dielectric constant of a three-layer structure using a microstrip resonator of a new shape. A number of solid and liquid materials were investigated experimentally. It is shown that the resonant frequency and quality factor of the resonator loaded with the investigated material allow to estimate the concentration of the components of binary solutions. The possibility of using a microstrip resonator as a plethysmographic sensor has been investigated. Results: An electromagnetic sensor for measuring the dielectric constant of objects with one-side access was developed. The description of the original design of the microstrip resonator is presented and its modeling and experimental research are carried out. The results of measurements of the dielectric constant of objects of different physical nature are obtained: solid dielectrics and biological liquids. The influence of relative glucose concentration on the resonant properties of the sensor was studied. The possibility of using the sensor as a plethysmographic sensor in biomedical systems is shown. Conclusion: Theoretical and experimental studies of a microstrip resonator of complex geometric shape, which are presented in the paper, confirmed the possibility of its use as a sensor of electrophysical parameters of materials with different dielectric constant and conductivity. A new method of blood flow registration is proposed, based on the fixation of changes in the effective dielectric constant of tissues containing blood vessels.

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Detection and Characterization of earth-like Planets

International Astronomical Union Colloquium ◽

10.1017/s0252921100014810 ◽

1997 ◽

Vol 161 ◽

pp. 299-311 ◽

Cited By ~ 22

Author(s):

Jean Marie Mariotti ◽

Alain Léger ◽

Bertrand Mennesson ◽

Marc Ollivier

Keyword(s):

Direct Detection ◽

Contrast Ratio ◽

Angular Size ◽

Physical Nature ◽

Major Axis ◽

Infrared Emission ◽

Space Technology ◽

Semi Major Axis ◽

Earth Like Planets ◽

Visible Wavelengths

AbstractIndirect methods of detection of exo-planets (by radial velocity, astrometry, occultations,...) have revealed recently the first cases of exo-planets, and will in the near future expand our knowledge of these systems. They will provide statistical informations on the dynamical parameters: semi-major axis, eccentricities, inclinations,... But the physical nature of these planets will remain mostly unknown. Only for the larger ones (exo-Jupiters), an estimate of the mass will be accessible. To characterize in more details Earth-like exo-planets, direct detection (i.e., direct observation of photons from the planet) is required. This is a much more challenging observational program. The exo-planets are extremely faint with respect to their star: the contrast ratio is about 10−10at visible wavelengths. Also the angular size of the apparent orbit is small, typically 0.1 second of arc. While the first point calls for observations in the infrared (where the contrast goes up to 10−7) and with a coronograph, the latter implies using an interferometer. Several space projects combining these techniques have been recently proposed. They aim at surveying a few hundreds of nearby single solar-like stars in search for Earth-like planets, and at performing a low resolution spectroscopic analysis of their infrared emission in order to reveal the presence in the atmosphere of the planet of CO H2O and O3. The latter is a good tracer of the presence of oxygen which could be, like on our Earth, released by biological activity. Although extremely ambitious, these projects could be realized using space technology either already available or in development for others missions. They could be built and launched during the first decades on the next century.

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Models of Thermodynamic Properties of Prominences

International Astronomical Union Colloquium ◽

10.1017/s0252921100065799 ◽

1979 ◽

Vol 44 ◽

pp. 349-355

Author(s):

R.W. Milkey

Keyword(s):

Thermodynamic Properties ◽

Mass Transport ◽

Emission Spectrum ◽

Thermodynamic Parameters ◽

Working Group ◽

Physical Processes ◽

Theoretical Concepts ◽

Group 3 ◽

Observational Techniques

The focus of discussion in Working Group 3 was on the Thermodynamic Properties as determined spectroscopically, including the observational techniques and the theoretical modeling of physical processes responsible for the emission spectrum. Recent advances in observational techniques and theoretical concepts make this discussion particularly timely. It is wise to remember that the determination of thermodynamic parameters is not an end in itself and that these are interesting chiefly for what they can tell us about the energetics and mass transport in prominences.

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The Interpretation of Solar Spectral Intensities

International Astronomical Union Colloquium ◽

10.1017/s0252921100108012 ◽

1988 ◽

Vol 102 ◽

pp. 329

Author(s):

R.W.P. McWhirter

Keyword(s):

Emission Measure ◽

Physical Nature ◽

Atomic Data ◽

The Sun ◽

Atomic Properties ◽

Outer Atmosphere ◽

Spectral Intensities ◽

Thin Plasma ◽

Number Of Authors

The intensity of a specrtal line from an optically thin plasma such as the outer atmosphere of the sun depends on both the atomic properties of the atomic ion responsible for the line and the physical nature of the plasma. In this paper we discuss the various ways in which the measured spectral intensities from the sun are used to discover something about the nature of the sun’s atmosphere. The technique has been referred to as the emission measure method. It has important limitations in terms of the accuracy of the specrtal data as well as the atomic data. We discuss some of these and suggest methods by which they may be assessed. The technique is illustrated by application to real observations from a number of authors.

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Sampling and analysis of the air-water interface with SEM and EDS of microlayers

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100157000 ◽

1989 ◽

Vol 47 ◽

pp. 1004-1005

Author(s):

Randall W. Smith ◽

John Dash

Keyword(s):

Heavy Metals ◽

Surface Microlayer ◽

Surface Films ◽

Water Interface ◽

Physical Processes ◽

Infrared Spectroscopic Analysis ◽

Eds Analysis ◽

Air Water Interface ◽

Significant Area ◽

Bulk Chemical

The structure of the air-water interface forms a boundary layer that involves biological ,chemical geological and physical processes in its formation. Freshwater and sea surface microlayers form at the air-water interface and include a diverse assemblage of organic matter, detritus, microorganisms, plankton and heavy metals. The sampling of microlayers and the examination of components is presently a significant area of study because of the input of anthropogenic materials and their accumulation at the air-water interface. The neustonic organisms present in this environment may be sensitive to the toxic components of these inputs. Hardy reports that over 20 different methods have been developed for sampling of microlayers, primarily for bulk chemical analysis. We report here the examination of microlayer films for the documentation of structure and composition.Baier and Gucinski reported the use of Langmuir-Blogett films obtained on germanium prisms for infrared spectroscopic analysis (IR-ATR) of components. The sampling of microlayers has been done by collecting fi1ms on glass plates and teflon drums, We found that microlayers could be collected on 11 mm glass cover slips by pulling a Langmuir-Blogett film from a surface microlayer. Comparative collections were made on methylcel1ulose filter pads. The films could be air-dried or preserved in Lugol's Iodine Several slicks or surface films were sampled in September, 1987 in Chesapeake Bay, Maryland and in August, 1988 in Sequim Bay, Washington, For glass coverslips the films were air-dried, mounted on SEM pegs, ringed with colloidal silver, and sputter coated with Au-Pd, The Langmuir-Blogett film technique maintained the structure of the microlayer intact for examination, SEM observation and EDS analysis were then used to determine organisms and relative concentrations of heavy metals, using a Link AN 10000 EDS system with an ISI SS40 SEM unit. Typical heavy microlayer films are shown in Figure 3.

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