− A method for the assessment of the dynamic behaviour of heavy current shunts is described, which is based on the evaluation of the shunt frequency response through spectral analysis of input and output measured signals. The method has been tested by applying it to simulated current impulses and experimented in the case of a pulse current, generated by the discharge of a cable capacitance, mea...

The level spectrum of a single-walled carbon nanotube rope, studied by transport spectroscopy, shows Zeeman splitting in a magnetic field parallel to the tube axis. The pattern of splittings implies that the spin of the ground state alternates by 12 as consecutive electrons are added. Other aspects of the Coulomb blockade characteristics, including the current-voltage traces and peak heights, a...

The aim of this study was to investigate the potential application metal foams in shell-tube recuperators. A356 aluminium foam cast around internal and external surfaces a thin-walled copper tube enhance heat transfer between separated water streams at different temperatures. results demonstrated that drastically increased efficiency due its large volumetric surface area high thermal conductivi...

Chlamydomonas reinhardtii is widely used to study many biological processes including biofuel production. Here, we present a rapid transformation technique for cell-walled Chlamydomonas strains without cell-wall removal using a square electric pulses-generating electroporator. This method could be applied to transformation of other industrially useful algae by optimizing the electric conditions.

We report optical properties of the smallest single-walled carbon nanotubes (SWNTs) with a diameter of only 3 A. These ultrasmall SWNTs are fabricated in the elliptical nanochannels of an AlPO-11 (AEL) single crystal. Polarized and resonant Raman scattering unambiguously revealed that these 0.3 nm SWNTs are of (2,2) armchair symmetry. Interestingly, the (2,2) armchair tube has two metastable gr...

the paper studies optimization of shell-and-tube heat exchangers using the particle swarm optimization technique. a total cost function is formulated based on initial and annual operating costs of the heat exchangers. six variables – shell inside diameter, tube diameter, baffle spacing, baffle cut, number of tube passes and tube layouts (triangular or square) – are considered as the design para...

Thick-walled cylindrical parts with external grooves are widely used in the automobile and aviation fields. Traditional processes for fabricating such components can’t meet requirements of properties efficiency. The dieless radial spinning process was proposed to produce thick-walled grooves. forming characteristics effects various parameters on were studied by using orthogonal tests finite ele...

In this work, we have performed a systematic study of the electrical transport properties both the resistivity and the thermoelectric power on bundles of single-walled carbon nanotubes SWCNTs , double-walled carbon nanotubes DWCNTs , and peapods derived from the same batch of initial SWNTs during in situ doping with potassium donor . The charge transfer effects in K-doping are similar in SWNTs ...

Effects of various factors affecting the rate of Carbon Nanotubes (CNTs) produced in a Swirled Floating Catalyst Chemical Vapour Deposition (SFCCVD) reactor were investigated. This study was performed in a vertical silica tube plug flow reactor developed by Iyuke at this University. Transmission Electron Microscopy (TEM) images revealed that both Single–Walled and Multi–Walled Carbon Nanotubes ...

The simulation of the optical properties of supramolecular aggregates requires the development of methods, which are able to treat a large number of coupled chromophores interacting with the environment. Since it is currently not possible to treat large systems by quantum chemistry, the Frenkel exciton model is a valuable alternative. In this work we show how the Frenkel exciton model can be ex...