planck distribution
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Biophysica ◽  
2021 ◽  
Vol 1 (2) ◽  
pp. 249-268
Author(s):  
Ming Chih Tsai ◽  
River Gassen ◽  
Kathrin Spendier

Magnetic nanoparticles (MNPs) are unique in their abilities to penetrate and interact with a wide range of liquid media. Because of their magnetic properties, MNPs can be directed to any area of interest, and interact with core structures deep inside the medium which is normally inaccessible. In this report, we investigate the behavior of MNPs in a specific biological fluid, namely in a mucus layer of air–liquid interface cultured primary normal human tracheobronchial epithelial cells. Using Fokker–Planck algorithm simulations and observing the behavior of MNPs from prior experiments, we found MNPs that are initially less than 100 nm in size, to aggregate into sizes of ~50 μm and to deviate from the expected Fokker–Planck distribution due to the mucus structure. Based on our analysis, human tracheobronchial epithelial (NHTE) cell mucus viscosity ranges from 15 Pa·s to 150 Pa·s. The results not only confirm the possible use of MNPs as a means for medical drug delivery but also underline important consequences of MNP surface modifications.



2020 ◽  
Vol 80 (12) ◽  
Author(s):  
Michael R. R. Good ◽  
Yen Chin Ong

AbstractThe Reissner–Nordström black hole – moving mirror correspondence is solved. The beta coefficients reveal that charge makes a black hole radiate fewer particles (neutral massless scalars) per frequency. An old Reissner–Nordström black hole emits particles in an explicit Planck distribution with temperature corresponding to the surface gravity of its outer horizon.



2020 ◽  
Vol 12 (4) ◽  
pp. 63
Author(s):  
Jiri Stavek

In our approach we have combined knowledge of Old Masters (working in this field before the year 1905), New Masters (working in this field after the year 1905) and Dissidents under the guidance of Louis de Broglie and David Bohm. Based on the great works of Wilhelm Wien and Max Planck we have presented a new look on the “Wien Peaks” and the Planck Distribution Function and proposed the “core-shell” model of the photon. There are known many “Wien Peaks” defined for different contexts. We have introduced a thermodynamic approach to define the Wien Photopic Peak at the wavelength λ = 555 nm and the Wien Scotopic Peak at the wavelength λ = 501 nm to document why Nature excellently optimized the human vision at those wavelengths. There could be discovered many more the so-called Wien Thermodynamic Peaks for other physical and chemical processes. We have attempted to describe the so-called Planck oscillators as coupled oscillations of geons and dyons. We have decomposed the Planck distribution function in two parts. Inspired by the Bohm Diffusion and the Bohm Sheath Criterion we have defined the plasma coupling constant that couple oscillations of geons and photons. The difference of the Planck least action of photons and the least action of geons might define the Barrier of Determinacy that create a limit for the resolution in the Microworld. We have newly formulated the Hubble cooling constant and inserted it into the Newton-Zwicky Cooling Law of photons for the description of the cooling of old photons. This proposed view on Planck´s Oscillators might open a new way for the description of “Heat” and “Light” processes.



Author(s):  
D. I. Klimov ◽  
◽  
T. T. Mamedov ◽  
I. R. Gubaidullin ◽  
◽  
...  

Nowadays the appearance of publications, scientific and research, and also research and development works on the creation of video monitoring systems for rocket and space technology products is caused by a well-known fact about the most reliable information channel — vision (human vision provides 95 % of information on surrounding objects), hence the inclusion of video information in the control system significantly increases the reliability of information from existing telemetry facilities of objects to track their normal functioning, as well as for rapid and unambiguous identification of the causes of abnormal and emergency situations that occur during the flight of rocket and space technology products. The article proposes a method for processing information from a video telemetry system about the temperature of thermally loaded elements of launch vehicles and upper stages by a remote contactless method with visual representation by converting a signal received from video cameras based on the principle of color pyrometers and Planck distribution. To implement the algorithm for processing video information for calculating the temperature, a block diagram of the solver is developed. A method for presenting video information and temperature measurements is presented provided that there is a color video image with a reduced frame rate and wide spectral range.



2019 ◽  
Vol 492 (2) ◽  
pp. 1902-1913 ◽  
Author(s):  
Hirotaka Ito ◽  
Amir Levinson ◽  
Shigehiro Nagataki

ABSTRACT Radiation-mediated shocks (RMS) play a key role in shaping the early emission observed in many transients. In most cases, e.g. shock breakout in supernovae, llGRBs, and neutron star mergers, the upstream plasma is devoid of radiation, and the photons that ultimately reach the observer are generated predominantly inside and downstream of the shock. Predicting the observed spectrum requires detailed calculations of the shock structure and thermodynamic state that account properly for the shock microphysics. We present results of self-consistent Monte Carlo simulations of photon-starved RMS, which yield the shock structure and emission for a broad range of shock velocities, from subrelativistic (βsh = 0.1) to highly relativistic (Γsh = 20). Our simulations confirm that in relativistic RMS the immediate downstream temperature is regulated by exponential pair creation, ranging from 50 keV at βsh = 0.5–200 keV at Γsh = 20. At lower velocities, the temperature becomes sensitive to the shock velocity, with kT ∼ 0.5 keV at βsh = 0.1. We also confirm that in relativistic shocks the opacity is completely dominated by newly created pairs, which has important implications for the breakout physics. We find the transition to pair dominance to occur at βsh = 0.5 roughly. In all cases examined, the spectrum below the νFν peak has been found to be substantially softer than the Planck distribution. This has important implications for the optical emission in fast and relativistic breakouts, and their detection. The applications to GRB 060218 and GRB 170817A are discussed.



2018 ◽  
Vol 168 ◽  
pp. 01012
Author(s):  
Leonardo Hsu ◽  
Jong-Ping Hsu

Based on the limiting continuation of Lorentz-Poincaré invariance, we propose an alternative formulation of the generalized Planck distribution for inertial and noninertial frames. The Lorentz invariant Planck distribution law leads to a new physical interpretation of the dipole anisotropy of the Cosmic Microwave Background. The Big Jets model predicts a distant ‘antimatter blackbody,’ whose radiations could make 50% of the sky very slightly warmer than the isotropic CMB temperature TCMB with a cosine function. The other 50% of the sky has the same isotropic temperature TCMB. Thus, we could have a pseudo-dipole anisotropy because the microwaves emitted from the antimatter blackbody are totally absorbed by our matter blackbody. We suggest that accurate data of satellite experiments might be used to search for the pseudo-dipole anisotropy and the missing half of the antimatter universe.



Author(s):  
Jochen Rau

The perfect gas is perhaps the most prominent application of statistical mechanics and for this reason merits a chapter of its own. This chapter briefly reviews the quantum theory of many identical particles, in particular the distinction between bosons and fermions, and then develops the general theory of the perfect quantum gas. It considers a number of limits and special cases: the classical limit; the Fermi gas at low temperature; the Bose gas at low temperature which undergoes Bose–Einstein condensation; as well as black-body radiation. For the latter we derive the Stefan–Boltzmann law, the Planck distribution, and Wien’s displacement law. This chapter also discusses the effects of a possible internal dynamics of the constituent molecules on the thermodynamic properties of a gas. Finally, it extends the theory of the perfect gas to dilute solutions.



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