scholarly journals Electron Bulk Heating at Saturn’s Magnetopause

2021 ◽  
Author(s):  
I Cheng ◽  
N. Achilleos ◽  
A. Masters ◽  
G. Lewis ◽  
M. Kane ◽  
...  
Keyword(s):  
Bulk Heating

Friction-Heating Maps and Their Applications

MRS Bulletin ◽  
1991 ◽  
Vol 16 (10) ◽  
pp. 41-48 ◽  
Author(s):  
H.S. Kong ◽  
M.F. Ashby
Keyword(s):  
Normal Force ◽  
Frictional Heat ◽  
Unified Approach ◽  
Magnetic Disks ◽  
Heat Flows ◽  
Bulk Heating ◽  
Friction Heating ◽  
Image Position ◽  
Pin On Disk ◽  
Nominal Contact Area

Friction is often a nuisance, but it can be useful too. Brakes, clutches, and tires rely on it, of course, though the inevitable fractional heat remains a problem. Other applications use frictional heat: friction cutting and welding, skiing, skating, and curling. The damage to magnetic disks caused by head-disk contact and the striking of matches are also examples.This article illustrates a framework where the thermal aspects of friction can be analyzed in an informative way. It uses a unified approach to the calculation of flash and bulk heating, and a helpful diagram—the frictional temperature map—to display the results. The method is approximate, but the approximations have been carefully chosen and calibrated to give precision adequate to most tasks, and the gain in simplicity is great.The symbols used in this article are defined in Table I.When two contacting solids 1 and 2, pressed together by a normal force F, slide at a relative velocity ν and with coefficient of friction ü, heat is generated at the surface where they meet. The heat generated, q, per unit of nominal contact area, An, per second isThe heat flows into the two solids, partitioned between them in a way that depends on their geometry and thermal properties. Figure 1 shows one geometry commonly used for laboratory tests: the pin-on-disk configuration. The pin is identified by the subscript 1, the disk by subscript 2. Solid 1 can have properties which differ from those of solid 2.

FUNGI ASSOCIATED WITH HOT SPOTS IN FARM STORED GRAIN

1962 ◽  
Vol 42 (1) ◽  
pp. 130-141 ◽  
Author(s):  
H. A. H. Wallace ◽  
R. N. Sinha
Keyword(s):  
Hot Spots ◽  
Viable Seed ◽  
Stored Grain ◽  
Surface Layers ◽  
Bulk Heating ◽  
Storage Fungi ◽  
Grain Bulks ◽  
Penicillium Spp ◽  
Water Contents

The temperature, moisture, germination and fungal relationships of normal and heated wheat and oats collected from grain bulks in 13 granaries in Manitoba and Saskatchewan were determined during the falls and winters of 1957–60. Eight bulks were studied in detail. It was found that hot spots could develop anywhere in a bin. Temperatures up to 53 °C. (in winter) were obtained and were usually highest at the base of the bulk. Heating grain was relatively dry (less than 11 per cent) except along the surface. The highest water contents (27 per cent) in the bulks always occurred in the gram along the surface layers. Loss of germinability could occur anywhere in the bulk. Field fungi, such as Alternaria, were common in viable seed, but negligible in heated grain. The seeds in hot spots were predominantly infected by storage fungi, among which Penicillium spp. were the most abundant, even in relatively dry grain at the 6-foot depth. Other fungi commonly found were Aspergillus spp., especially A. flavus Link, A. fumigatus Fresenius, A. versicolor (Vuillemin) Tiraboschi and Absidia spp. Actinomycetes (Streptomyces) were common in some heating grain bulks.

scholarly journals Denaturation of the SARS-CoV-2 spike protein under non-thermal microwave radiation

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Pooya Afaghi ◽  
Michael Anthony Lapolla ◽  
Khashayar Ghandi
Keyword(s):  
Electromagnetic Field ◽  
Body Temperature ◽  
Microwave Radiation ◽  
Human Body ◽  
Viral Entry ◽  
Thermal Denaturation ◽  
Spike Protein ◽  
Heating Effect ◽  
Bulk Heating ◽  
Human Body Temperature

AbstractSARS-CoV-2, the virus that causes COVID-19, is still a widespread threat to society. The spike protein of this virus facilitates viral entry into the host cell. Here, the denaturation of the S1 subunit of this spike protein by 2.45 GHz electromagnetic radiation was studied quantitatively. The study only pertains to the pure electromagnetic effects by eliminating the bulk heating effect of the microwave radiation in an innovative setup that is capable of controlling the temperature of the sample at any desired intensity of the electromagnetic field. This study was performed at the internal human body temperature, 37 °C, for a relatively short amount of time under a high-power electromagnetic field. The results showed that irradiating the protein with a 700 W, 2.45 GHz electromagnetic field for 2 min can denature the protein to around 95%. In comparison, this is comparable to thermal denaturation at 75 °C for 40 min. Electromagnetic denaturation of the proteins of the virus may open doors to potential therapeutic or sanitation applications.

scholarly journals Irreversible thermodynamics of transport across interfaces

2011 ◽  
Vol 89 (10) ◽  
pp. 1041-1050 ◽  
Author(s):  
Matthew R. Sears ◽  
Wayne M. Saslow
Keyword(s):  
Entropy Production ◽  
Electric Current ◽  
Heating Rate ◽  
Chemical Potential ◽  
Magnetic Semiconductors ◽  
Spin Current ◽  
Irreversible Thermodynamics ◽  
Heat Current ◽  
Bulk Heating ◽  
Current Production

With spintronics applications in mind, we use irreversible thermodynamics to derive the rates of entropy production and heating near an interface when heat current, electric current, and spin current cross it. Associated with these currents are apparent discontinuities in temperature (ΔT), electrochemical potential (Δ[Formula: see text]), and spin-dependent “magnetoelectrochemical potential” (Δ[Formula: see text]). This work applies to magnetic semiconductors and insulators as well as metals, because of the inclusion of the chemical potential, μ, which is usually neglected in works on interfacial thermodynamic transport. We also discuss the (nonobvious) distinction between entropy production and heat production. Heat current and electric current are conserved, but spin current is not, so it necessitates a somewhat different treatment. At low temperatures or for large differences in material properties, the surface heating rate dominates the bulk heating rate near the surface. We also consider the case where bulk spin currents occur in equilibrium. Although a surface spin current (in A/m2) should yield about the same rate of heating as an equal surface electric current, production of such a spin current requires a relatively large “magnetization potential” difference across the interface.

scholarly journals Bulk heating effects as tests for collapse models

2018 ◽  
Vol 97 (5) ◽  
Author(s):  
Stephen L. Adler ◽  
Andrea Vinante
Keyword(s):  
Bulk Heating ◽  
Heating Effects ◽  
Collapse Models

Photoluminescence Studies of Impurities and Defects in Mercuric Iodide

1989 ◽  
Vol 163 ◽  
Author(s):  
X.J. Bao ◽  
T.E. Schlesinger ◽  
R.B. James ◽  
A.Y. Cheng ◽  
C. Ortale
Keyword(s):  
Chemical Etching ◽  
Front Surface ◽  
Photoluminescence Spectra ◽  
Mercuric Iodide ◽  
Contact Materials ◽  
Bulk Heating ◽  
Photoluminescence Studies ◽  
Nuclear Detectors ◽  
Processing Steps ◽  
Impurities And Defects

AbstractWe have studied the effects of chemical etching in potassium iodide(KI) aqueous solution, vacuum exposure and bulk heating on the photoluminescence(PL) spectra of mercuric i0dide(HgI2). Different contact materials deposited onto HgI2 were also investigated, such as Pd, Cu, Al, Ni, Sn, In, Ag and Ta. These processing steps and the choice of a suitable electrode material are very important in the manufacturing of high-quality mercuric iodide nuclear detectors. Comparisons are made between the front surface photoluminescence and transmission photoluminescence spectra.

scholarly journals Localized Heating Near a Rigid Spherical Inclusion in a Viscoelastic Binder Material Under Compressional Plane Wave Excitation

2017 ◽  
Vol 84 (4) ◽  
Author(s):  
Jesus O. Mares ◽  
Daniel C. Woods ◽  
Caroline E. Baker ◽  
Steven F. Son ◽  
Jeffrey F. Rhoads ◽  
...  
Keyword(s):  
Energetic Materials ◽  
Scale Effects ◽  
Spherical Inclusion ◽  
Plane Waves ◽  
Thermal Response ◽  
Resonant Scattering ◽  
Compressional Waves ◽  
Dynamic Events ◽  
Bulk Heating ◽  
Viscoelastic Effects

High-frequency mechanical excitation has been shown to generate heat within composite energetic materials and even induce reactions in single energetic crystals embedded within an elastic binder. To further the understanding of how wave scattering effects attributable to the presence of an energetic crystal can result in concentrated heating near the inclusion, an analytical model is developed. The stress and displacement solutions associated with the scattering of compressional plane waves by a spherical obstacle (Pao and Mow, 1963, “Scattering of Plane Compressional Waves by a Spherical Obstacle,” J. Appl. Phys., 34(3), pp. 493–499) are modified to account for the viscoelastic effects of the lossy media surrounding the inclusion (Gaunaurd and Uberall, 1978, “Theory of Resonant Scattering From Spherical Cavities in Elastic and Viscoelastic Media,” J. Acoust. Soc. Am., 63(6), pp. 1699–1712). The results from this solution are then utilized to estimate the spatial heat generation due to the harmonic straining of the material, and the temperature field of the system is predicted for a given duration of time. It is shown that for certain excitation and sample configurations, the elicited thermal response near the inclusion may approach, or even exceed, the decomposition temperatures of various energetic materials. Although this prediction indicates that viscoelastic heating of the binder may initiate decomposition of the crystal even in the absence of defects such as initial voids or debonding between the crystal and binder, the thermal response resulting from this bulk heating phenomenon may be a precursor to dynamic events associated with such crystal-scale effects.

Excimer laser cleaning, annealing, and ablation of β–SiC

1989 ◽  
Vol 4 (6) ◽  
pp. 1480-1490 ◽  
Author(s):  
Pehr E. Pehrsson ◽  
Ray Kaplan
Keyword(s):  
Excimer Laser ◽  
Photoelectron Spectroscopy ◽  
Ex Situ ◽  
Carbon Surface ◽  
Laser Exposure ◽  
Electron Loss ◽  
Bulk Heating ◽  
Surface Contaminants ◽  
Excimer Laser Irradiation

The effects of ArF excimer laser irradiation on β–SiC in UHV were examined for a variety of laser intensities and pulse densities. The samples were analyzed in situ with Auger and electron loss spectroscopies, and ex situ with x-ray photoelectron spectroscopy. With progressively higher laser intensities, the SiC surface was initially cleaned of carbon and oxygen surface contaminants, and the Si–LVV Auger lineshape changed from the oxide to the carbide. Still higher laser intensities then partially reordered the surface. A carbon surface layer developed, and the C-KLL lineshape transformed from carbidic to graphitic. Finally, the surface segregated into an almost pure Si layer and an underlying carbon-rich layer, followed by ablation and pitting. Bulk heating during laser exposure may enhance reordering of sputtered or implanted material.

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