Electromagnetic Field of a Cylinder with a Periodic Current: Energy Flux from a Relativistic Jet

Astrophysics ◽  
2004 ◽  
Vol 47 (3) ◽  
pp. 404-411 ◽  
Author(s):  
G. S. Bisnovatyi-Kogan
Keyword(s):  
Electromagnetic Field ◽  
Energy Flux ◽  
Relativistic Jet ◽  
Periodic Current ◽  
Current Energy

Studies of Microwave Electromagnetic Field Influence on Adhesion Strength of the “Matrix-Fiber” Contact Zone on the Example of the Elementary Cell of a Certified Polymeric Composite Material

2020 ◽  
Vol 992 ◽  
pp. 317-324
Author(s):  
I.V. Zlobina ◽  
N.V. Bekrenev ◽  
G. Muldasheva
Keyword(s):  
Electromagnetic Field ◽  
Contact Zone ◽  
Adhesion Strength ◽  
Energy Flux ◽  
Polymeric Composite Material ◽  
Adhesive Interaction ◽  
Interlayer Shear ◽  
Fiber Contact ◽  
Short Term Exposure ◽  
The Matrix

The strength characteristics of polymer composites (PCM) reinforced with fibers of various nature largely depend on the adhesion strength of the components in the matrix-fiber contact zone, determined by the mechanisms of their adhesive interaction. The strength of the bonds in the contact zone depends on the transfer of the load from fiber to fiber through the matrix layer. Taking into account the order and greater strength of the reinforcing fibers in tension, compared with the matrix material, the adhesion of the PCM components has the greatest effect when the material is perceived as transverse to the direction of the fiber loads, which usually occurs in bending and interlayer shear. In the latter case, the strength of the material several times less, which determines the importance of increasing the strength of the adhesive interaction, which requires comprehensive studies and an adequate description of its mechanisms. An experimental study of the adhesion strength in the matrix-fiber contact zone after short-term exposure to a microwave electromagnetic field with different energy flux densities on the PCM physical cell model, represented as a basalt fiber bundle placed in ED-20 epoxy resin, was performed. It has been established that exposure to a microwave electromagnetic field with an energy flux density of (17-18) x104 μW/cm2 for 1-2 minutes leads to an increase in adhesion relative to the source material by no less than 32%. This method can be used as a basis for the development of technologies for increasing the strength of the interlayer shear PCM, reinforced by fibers of various nature. To clarify the mechanisms of the obtained results, it is advisable to conduct a study of the micro-and nanostructures of the “matrix-fiber” contact zone using electron and atomic-force microscopy and its phase composition..

Distribution of Electromagnetic Field and Energy Flux in the Thin Film Solar Cell with Silver Nano-Disk Array

2013 ◽  
Vol 669 ◽  
pp. 194-203
Author(s):  
Hong Zhou ◽  
Xiao Ping Huang ◽  
Lei Zhong ◽  
Sheng Kang Ji ◽  
Yan Pang ◽  
...  
Keyword(s):  
Thin Film ◽  
Electromagnetic Field ◽  
Solar Cell ◽  
Field Distribution ◽  
Energy Flux ◽  
Thin Film Solar Cell ◽  
Incident Light ◽  
Fdtd Method ◽  
Absorption Enhancement ◽  
Electromagnetic Field Distribution

We simulate and calculate numerically the electromagnetic field and energy flux in single crystal silicon thin film solar cell coated with silver nano-disk square array by using the finite-difference time-domain (FDTD) method. Because of the surface plasmon resonance (SPR) of silver nano array, the electromagnetic field is redistributed and enhanced in the solar cell. The simulation results show that the electromagnetic field distribution and corresponding energy flux component depend on the nano array and the structure of absorbed layer in solar cell. The wavelength of the incident light relative to the nano array determine the profile of the electric field around the nano array. The electromagnetic field distribution in thin film is determined by the internal structure of solar cell. For different incident wavelengths, the electromagnetic field distribution in solar cell will changes. The energy flux named as Poynting vector also changes with the incident wavelength. To investigate the absorption of the solar cell, the normalized absorbed power at different wavelengths is calculated. Based on the SPR effect, the solar cell exhibts absorption enhancement sharply at a certain wavelength.

scholarly journals RESEARCH AND EVALUATION OF THE ENERGY FLUX DENSITY OF THE MOBILE PHONE ELECTROMAGNETIC FIELD / MOBILIŲJŲ TELEFONŲ ELEKTROMAGNETINIO LAUKO ENERGIJOS SRAUTO TANKIO TYRIMAI IR ĮVERTINIMAS

2012 ◽  
Vol 5 (4) ◽  
pp. 462-467
Author(s):  
Pranas Baltrėnas ◽  
Raimondas Buckus
Keyword(s):  
Electromagnetic Field ◽  
Mobile Phone ◽  
Flux Density ◽  
Energy Flux ◽  
Text Message ◽  
Text Messages ◽  
Mobile Internet ◽  
Effective Protection ◽  
Allowable Limit ◽  
Energy Flux Density

The article analyses variations in the energy flux density of the electromagnetic field of 10 mobile phones depending on distance. The studies have been conducted using three modes: sending a text message, receiving a text message and connecting a mobile phone to the Internet. When text messages are received or sent from a mobile phone, the values of the energy flux density of the mobile phone electromagnetic field exceed the safe allowable limit and make 10 μW / cm². A distance of 10, 20 and 30 cm from a mobile phone is effective protection against the energy flux density of the electromagnetic field when writing texts, receiving messages or connecting to the mobile Internet. Santrauka Nagrinėjami 10 mobiliųjų telefonų elektromagnetinių laukų energijos srauto tankio kitimai priklausomai nuo atstumo. Tyrimai atliekami, kai iš mobiliojo telefono siunčiamas SMS, kai į mobilųjį telefoną yra siunčiamas SMS iš kito mobiliojo telefono, kai mobilusis telefonas jungiamas prie mobiliojo interneto. Mobiliųjų telefonų elektromagnetinio lauko energijos srauto tankio vertės, kai iš mobiliojo telefono siunčiamas ar gaunamas SMS, viršija saugią leistiną 10 µW/cm² normą. 10, 20, 30 cm atstumas nuo mobiliojo telefono – tinkama apsauga nuo elektromagnetinio lauko energijos srauto tankio viršijimo rašant ar gaunant SMS žinutes, jungiantis prie mobiliojo interneto. Mobiliųjų telefonų elektromagnetinių laukų energijos srauto tankio priklausomybė nuo atstumo pateikiama grafikais.

The gravitational-electromagnetic Noether operator and the second-order energy flux

1991 ◽  
Vol 435 (1895) ◽  
pp. 635-644 ◽  
Keyword(s):  
Electromagnetic Field ◽  
Stress Tensor ◽  
Stationary Solution ◽  
Energy Flux ◽  
Second Order ◽  
First Order ◽  
Energy Current ◽  
Order Energy

The Noether operator for gravity is recalled and that for the electromagnetic field derived, its difference from the electromagnetic stress tensor being pointed out. It is then shown how the Noether operator’s defining equation leads, in the case of perturbations about a stationary solution, to a conserved energy current depending quadratically on the first-order perturbations alone. The formal background of the paper by Chandrasekhar & Ferrari is thereby clarified.

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