In recent years energy shortage and environmental impacts due to consuming fossil fuels have led to developing renewable energy sources systems. Since these sources are not reliable and are usually time dependent, an energy storing system like hydrogen production is required. In this regard, PEM electrolyzer can be efficiently used to decompose liquid water into hydrogen and oxygen. Because of ...

Quiescence and burst emission and relativistic particle winds of soft gamma-ray repeaters (SGRs) have been widely interpreted to result from ultrastrongly magnetized neutron stars. In this magnetar model, the magnetic energy and gravitational energy of the neutron stars are suggested as the energy sources of all the emission and winds. However, Harding, Contopoulos & Kazanas (1999) have shown t...

In this review it will be attempted to briefly cover some of the recent developments in the observation of photons and neutrinos to constrain models on the origin and acceleration of cosmic rays. It appears that EGRET on board of CGRO provides most valuable new data in that context. Data from high energy airshower arrays and Tscherenkov telescopes add to the picture although not yet strong enou...

We present a new linear inversion formalism for the scalar inverse source problem in three-dimensional and one-dimensional (1D) spaces, from which a number of previously unknown results on minimum-energy (ME) sources and their fields readily follow. ME sources, of specified support, are shown to obey a homogeneous Helmholtz equation in the interior of that support. As a consequence of that resu...

I give a brief critical review of the predicted intensity of diffuse high energy neutrinos of astrophysical origin over the energy range from ∼ 10 eV to ∼ 10 eV. Neutrinos from interactions of galactic cosmic rays with interstellar matter are guaranteed, and the intensity can be reliably predicted to within a factor of 2 up to 10 eV. Somewhat less certain are intensities in the same energy rang...

A busca contínua por fontes alternativas de energia, imposta por interesses econômicos e ambientais, tem motivado investigações sobre alternativas limpas e eficientes para a produção de energia. As células a combustível são uma estratégia potencialmente eficaz para a conversão de energia. As biocélulas a combustível constituem uma subclasse das células a combustível, que possuem grande potencia...

Renewable and non-conventional distributed energy resources (DERs), such as, wind, solar PV, micro-turbines, fuel cells, diesel generators etc. are gradually becoming more popular as energy efficient and low-emission energy sources. Demand-side management, along with the integration of distributed energy generation and storage, are considered increasingly essential elements for implementing the...