scholarly journals Novelty Surface Coatings for Far Infrared Spectrum Black Body Radiators

2021 ◽  
Vol 25 (4) ◽  
pp. 77-82
Author(s):  
Andrzej Ligienza ◽  
Grzegorz Bieszczad ◽  
Tomasz Sosnowski ◽  
Bartosz Bartosewicz ◽  
Krzysztof Firmanty
Keyword(s):  
Thermal Imaging ◽  
Far Infrared ◽  
Black Body ◽  
Black Body Radiation ◽  
Surface Coatings ◽  
Reference Surface ◽  
Emitter Surface ◽  
Radiation Sources ◽  
Physical Approximation ◽  
Planck’S Law

Black body radiation sources are commonly used devices in areas related to thermal imaging and radiometry. They are the closest physical approximation of theoretical black body emitter derived from the Planck’s law. Majority of such devices are costly with restricted information about their production technology, including their emitter surface. A few relatively easily accessible coatings with potential application in such devices have been chosen and their emissivity measured. The paper presents measurements that provides information necessary to determine whether there are coatings viable for black body emitter or reference surface.

scholarly journals The Bose-Einstein statistics: Remarks on Debye, Natanson, and Ehrenfest contributions and the emergence of indistinguishability principle for quantum particles

2020 ◽  
Vol 19 ◽  
pp. 423-441
Author(s):  
Józef Spałek
Keyword(s):  
Black Body ◽  
Black Body Radiation ◽  
Quantum Particles ◽  
Particle Wave Function ◽  
Planck’S Law ◽  
The Many ◽  
Bose Einstein ◽  
Grand Canonical ◽  
Fundamental Physical

The principal mathematical idea behind the statistical properties of black-body radiation (photons) was introduced already by L. Boltzmann (1877/2015) and used by M. Planck (1900; 1906) to derive the frequency distribution of radiation (Planck’s law) when its discrete (quantum) structure was additionally added to the reasoning. The fundamental physical idea – the principle of indistinguishability of the quanta (photons) – had been somewhat hidden behind the formalism and evolved slowly. Here the role of P. Debye (1910), H. Kamerlingh Onnes and P. Ehrenfest (1914) is briefly elaborated and the crucial role of W. Natanson (1911a; 1911b; 1913) is emphasized. The reintroduction of this Natanson’s statistics by S. N. Bose (1924/2009) for light quanta (called photons since the late 1920s), and its subsequent generalization to material particles by A. Einstein (1924; 1925) is regarded as the most direct and transparent, but involves the concept of grand canonical ensemble of J. W. Gibbs (1902/1981), which in a way obscures the indistinguishability of the particles involved. It was ingeniously reintroduced by P. A. M. Dirac (1926) via postulating (imposing) the transposition symmetry onto the many-particle wave function. The above statements are discussed in this paper, including the recent idea of the author (Spałek 2020) of transformation (transmutation) – under specific conditions – of the indistinguishable particles into the corresponding to them distinguishable quantum particles. The last remark may serve as a form of the author’s post scriptum to the indistinguishability principle.

Are smaller microplastics missing?

2020 ◽  
Author(s):  
Kunihiro Aoki ◽  
Ryo Furue
Keyword(s):  
Size Distribution ◽  
Gradual Increase ◽  
Black Body ◽  
Boltzmann Distribution ◽  
Black Body Radiation ◽  
Rapid Decrease ◽  
Size Distributions ◽  
Biological Uptake ◽  
Data Source ◽  
Planck’S Law

Abstract The size distribution of marine microplastics (< 5 mm) provides a fundamental data source for understanding the dispersal, break down, and biotic impacts of the microplastics in the ocean. The observed size distribution generally shows, from large to small sizes, a gradual increase followed by a rapid decrease. This decrease has led to the hypothesis that the smallest fragments are selectively removed by sinking or biological uptake. Here we propose a new model of size distribution without any removal of material from the system. The model uses an analogy with black-body radiation and the resultant size distribution is analogous to Planck's law. In this model, the original large plastic piece is broken into smaller pieces once by the application of “energy” or work by waves or other processes, under two assumptions, one that fragmentation into smaller pieces requires larger energy and the other that the probability distribution of the “energy” follows the Boltzmann distribution. Our formula well reproduces observed size distributions over wide size ranges from micro- (< 5 mm) to mesoplastics ( > 5 mm). According to this model, the smallest fragments are fewer because large “energy” required to produce such small fragments occurs more rarely.

Far-Infrared Fresnel Lens for Thermal Imaging

2013 ◽  
Vol 133 (7) ◽  
pp. 274-279
Author(s):  
Tomoyuki Takahata ◽  
Kiyoshi Matsumoto ◽  
Isao Shimoyama
Keyword(s):  
Thermal Imaging ◽  
Far Infrared ◽  
Fresnel Lens

The Physical World

2017 ◽  
Author(s):  
Nicholas Manton ◽  
Nicholas Mee
Keyword(s):  
Quantum Mechanics ◽  
Particle Physics ◽  
Variational Principles ◽  
Black Body ◽  
Black Body Radiation ◽  
Physical World ◽  
Atomic Scale ◽  
Solid State Physics ◽  
Least Action ◽  
Dimensional Spacetime

The book is an inspirational survey of fundamental physics, emphasizing the use of variational principles. Chapter 1 presents introductory ideas, including the principle of least action, vectors and partial differentiation. Chapter 2 covers Newtonian dynamics and the motion of mutually gravitating bodies. Chapter 3 is about electromagnetic fields as described by Maxwell’s equations. Chapter 4 is about special relativity, which unifies space and time into 4-dimensional spacetime. Chapter 5 introduces the mathematics of curved space, leading to Chapter 6 covering general relativity and its remarkable consequences, such as the existence of black holes. Chapters 7 and 8 present quantum mechanics, essential for understanding atomic-scale phenomena. Chapter 9 uses quantum mechanics to explain the fundamental principles of chemistry and solid state physics. Chapter 10 is about thermodynamics, which is built around the concepts of temperature and entropy. Various applications are discussed, including the analysis of black body radiation that led to the quantum revolution. Chapter 11 surveys the atomic nucleus, its properties and applications. Chapter 12 explores particle physics, the Standard Model and the Higgs mechanism, with a short introduction to quantum field theory. Chapter 13 is about the structure and evolution of stars and brings together material from many of the earlier chapters. Chapter 14 on cosmology describes the structure and evolution of the universe as a whole. Finally, Chapter 15 discusses remaining problems at the frontiers of physics, such as the interpretation of quantum mechanics, and the ultimate nature of particles. Some speculative ideas are explored, such as supersymmetry, solitons and string theory.

Constructing Quantum Mechanics

2019 ◽  
Author(s):  
Anthony Duncan ◽  
Michel Janssen
Keyword(s):  
Quantum Mechanics ◽  
Quantum Theory ◽  
Stark Effect ◽  
Zeeman Effect ◽  
Black Body ◽  
Black Body Radiation ◽  
Wave Mechanics ◽  
Specific Heats ◽  
Old Quantum Theory ◽  
Upper Level

This is the first of two volumes on the genesis of quantum mechanics. It covers the key developments in the period 1900–1923 that provided the scaffold on which the arch of modern quantum mechanics was built in the period 1923–1927 (covered in the second volume). After tracing the early contributions by Planck, Einstein, and Bohr to the theories of black‐body radiation, specific heats, and spectroscopy, all showing the need for drastic changes to the physics of their day, the book tackles the efforts by Sommerfeld and others to provide a new theory, now known as the old quantum theory. After some striking initial successes (explaining the fine structure of hydrogen, X‐ray spectra, and the Stark effect), the old quantum theory ran into serious difficulties (failing to provide consistent models for helium and the Zeeman effect) and eventually gave way to matrix and wave mechanics. Constructing Quantum Mechanics is based on the best and latest scholarship in the field, to which the authors have made significant contributions themselves. It breaks new ground, especially in its treatment of the work of Sommerfeld and his associates, but also offers new perspectives on classic papers by Planck, Einstein, and Bohr. Throughout the book, the authors provide detailed reconstructions (at the level of an upper‐level undergraduate physics course) of the cental arguments and derivations of the physicists involved. All in all, Constructing Quantum Mechanics promises to take the place of older books as the standard source on the genesis of quantum mechanics.

Electromagnetic fluctuations from energetic particles in plasmas

1988 ◽  
Vol 40 (3) ◽  
pp. 407-417 ◽  
Author(s):  
Cheng Chu ◽  
J. L. Sperling
Keyword(s):  
Distribution Function ◽  
Velocity Distribution ◽  
Charged Particles ◽  
Velocity Distribution Function ◽  
Black Body ◽  
Black Body Radiation ◽  
Specific Model ◽  
Magnetized Plasma ◽  
Plasma Power ◽  
Correlation Techniques

Electromagnetic fluctuations, induced by energetic charged particles, are calculated using correlation techniques for a uniform magnetized plasma. Power emission in the ion-cyclotron range of frequencies (ICRF) is calculated for a specific model of velocity distribution function. The emissive spectra are distinct from that of the black-body radiation and have features that are consistent with experimental observation.

DOES LIOUVILLE'S THEOREM IMPLY QUANTUM MECHANICS?

1999 ◽  
Vol 13 (02) ◽  
pp. 161-189
Author(s):  
C. SYROS
Keyword(s):  
Quantum Mechanics ◽  
Radiation Spectrum ◽  
Black Body ◽  
Boltzmann Distribution ◽  
Black Body Radiation ◽  
Planck Constant ◽  
Klein Gordon ◽  
Energy Variable ◽  
Liouville’S Theorem ◽  
Liouville’S Equation

The essentials of quantum mechanics are derived from Liouville's theorem in statistical mechanics. An elementary solution, g, of Liouville's equation helps to construct a differentiable N-particle distribution function (DF), F(g), satisfying the same equation. Reality and additivity of F(g): (i) quantize the time variable; (ii) quantize the energy variable; (iii) quantize the Maxwell–Boltzmann distribution; (iv) make F(g) observable through time-elimination; (v) produce the Planck constant; (vi) yield the black-body radiation spectrum; (vii) support chronotopology introduced axiomatically; (viii) the Schrödinger and the Klein–Gordon equations follow. Hence, quantum theory appears as a corollary of Liouville's theorem. An unknown connection is found allowing the better understanding of space-times and of these theories.

Effect of Surface Roughness on the Total Hemispherical and Specular Reflectance of Metallic Surfaces

1964 ◽  
Vol 86 (2) ◽  
pp. 193-199 ◽  
Author(s):  
R. C. Birkebak ◽  
E. M. Sparrow ◽  
E. R. G. Eckert ◽  
J. W. Ramsey
Keyword(s):  
Surface Roughness ◽  
Black Body ◽  
Black Body Radiation ◽  
The Other ◽  
Angle Of Incidence ◽  
Metallic Surfaces ◽  
Specular Reflectance ◽  
Other Hand ◽  
Hemispherical Reflectance ◽  
Effect Of Surface

Measurements have been made of the hemispherical and specular reflectance of metallic surfaces of controlled roughness. The surfaces, which were ground nickel rectangles, were irradiated at various angles of incidence by a beam of black-body radiation, the temperature of which was also varied. The instrumentation which was devised to perform the experiments is described. The measurements show that beyond a certain surface roughness, the hemispherical reflectance is virtually independent of further increases in roughness. On the other hand, the specular reflectance decreases steadily with increasing roughness. Additionally, the hemispherical reflectance is found to be quite insensitive to the angle of incidence, while the specular reflectance increases with angle of incidence for the rougher surfaces.

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