The characteristics of arbitrary amplitude dust ion acoustic solitary waves (DIASWs) are studied in unmagnetized dusty plasmas whose constituents are cold uid ions, nonextensive electrons and stationary negative/positive dust particles. The pseudopotential approach has been used to investigate the structure of localized waves. It is found that, solitary waves exist in a definite interval for th...

diesel exhaust particles are a complex mixture of thousands of gases and fine substances that contain more than 40 different environmental contaminants. being exposed to these exhaust particles (called soot) can cause lung damage and respiratory problems. diesel particulate filters are used in many countries for mobile sources as a legal obligation to decrease harmful effect of these fine parti...

This work is concerned with the diffraction and scattering of plane electro-acoustic waves by an interfacial crack between two dissimilar piezoelectric half-spaces. An exact solution is obtained for the full scattering field around the tip of the interfacial crack that is loaded with both acoustic SH and electric incident waves. First, it has been found that the interfacial crack is not complet...

Observations of baryon acoustic oscillations (BAO) in the clustering of galaxies offer an attractive method for setting cosmological constraints. The physics of the BAO production is well understood, and it is hard to imagine that galaxy formation processes will significantly distort this large-scale signal. The large volume of the Universe and redshift range probed by proposed SKA surveys will...

Through analytic techniques verified by numerical calculations, we establish general relations between the matter and cosmic microwave background (CMB) power spectra and their dependence on cosmological parameters on small scales. Fluctuations in the CMB, baryons, cold dark matter (CDM), and neutrinos receive a boost at horizon crossing. Baryon drag on the photons causes alternating acoustic pe...

Through analytic techniques veri ed by numerical calculations, we establish general relations between the matter and cosmic microwave background (CMB) power spectra and their dependence on cosmological parameters on small scales. Fluctuations in the cosmic microwave background (CMB), baryons, cold dark matter, and neutrinos receive a boost at horizon crossing. Baryon drag on the photons causes ...

We propose a novel mechanism for production of baryonic asymmetry in the early Universe. The mechanism takes advantage of the strong first order phase transition that produces runaway bubbles in the hidden sector that propagate almost without friction with ultra-relativistic velocities. Collisions of such bubbles can non-thermally produce heavy particles that further decay out-of-equilibrium in...

Acoustic logging while drilling (LWD) may be complicated because of contamination by waves propagating along the drill collar (the tool waves). In this paper we propose a new method for separating tool waves from the true formation acoustic arrivals in borehole acoustic LWD. The method utilizes the seismoelectric signal induced by the acoustic wave at the fluid-formation boundary. The basis for...