Ultra-intense, narrow-bandwidth, electromagnetic pulses have become important tools for exploring the characteristics of matter. Modern tuneable high-power light sources, such as free-electron lasers and vacuum tubes, rely on bunching of relativistic or near-relativistic electrons in vacuum. Here we present a fundamentally different method for producing narrow-bandwidth radiation from a broad s...

in this work at the first step calcium hydroxide nano-particles were synthesized via sono-chemical method at room temperature. at the second step aminated multi-walled carbon nano-tubes was prepared via chemical modification of surfaces of cnt. finally modified-mwcnt and ca(oh)2 were added to paraloid matrix by aid of ultrasonic irradiation. paraloid-modified-mwcnt-ca(oh)2 nanocomposite was use...

a comparison of buckling analysis of the nanoplate and nanocomposite plate with central square hole embedded in winkler foundation is presented in this article. in order to enhance mechanical properties of nanoplate with central cut out, carbon nano tubes (cnts) are applied as uniform distribution (ud) through thickness direction. in order to define the shape function of plate with square cut o...

Controlled silicon structures on the micron to nanometer order have received much attention owing to their potential applications in various fields such as electrochemical, optoelectrical, and biological sciences. Although the techniques commonly used in fabricating nano-/microstructured silicon are conventional lithographic techniques using a resist mask with an optical, electron, or X-ray bea...

In the manufacturing of hypotubes for coronary applications, austenitic steels types 304, or 316 L are being used. The process involves bending steel strips into tubes and continuous longitudinal welding tubes. Manufacturing also includes heat treatments stretching operations to achieve an external/internal diameter 0.35/0.23 mm, with a tolerance +/? 0.01 mm. Austenitic sensitive localized corr...

A method for producing high surface area nano-sized mesoporous alumina from inexpensive Iranian kaolin as raw material is proposed. In this method, first, kaolin was purified for purifying Kaolin, High Grade Magnetic Separation and leaching with HCl and chemical bleaching treatment by using sodium dithionite (Na 2 S 2O4 ) as reducing agent in acidic media (H 2SO 4 ) were used. Pur...

We report the self-assembly of single crystals of single-walled carbon nanotubes (SWCNTs) using thermolysis of nano-patterned precursors. The synthesis of these perfectly ordered, single crystals of SWCNTs results in extended structures with dimension on the micrometer scale. Each crystal is composed of an ordered array of tubes with identical diameters and chirality, although these properties ...

An experiment has been carried out at the Brookhaven Accelerator Test Facility to investigate the effect of a surface-roughness wakefield in narrow beam tubes with artificially created bumps. The measurements show that the synchronous modes decay significantly due to the randomization of the roughness pattern. It is pointed out that this decay mechanism has not been investigated in the previous...