Linear passive vibration absorbers, such as tuned mass dampers, often contain springs, dampers and masses, although recently there has been a growing trend to employ or supplement the mass elements with inerters. When considering possible configurations with these elements broadly, two approaches are normally used: one structure-based and one immittance-based. Both approaches have their advanta...

A hollow fibre (HF) polypropylene membrane gas absorber was investigated for the removal of hydrogen sulphide (H2S) from gas streams. Gas concentrations between 25-2010 ppmV were fed into the shell side of a membrane module whilst water-NaOH solutions flowed counter-currently in the fibre lumens. The process was effective at removing the H2S (96% at G:L ratios up to 50 and pH 13) from the gas p...

Abstract—This paper deals with the analytical investigation of thermal and thermohydraulic performance of double flow solar air heaters with corrugated and flat plate absorber. A mathematical model of double flow solar air heater has been presented, and a computer program in C++ language is developed to estimate the outlet temperature of air for the evaluation of thermal and thermohydraulic eff...

We propose a method for detecting gravitational magnification of distant sources, like quasars, due to absorber systems detected in their spectra. We first motivate the use of metal absorption lines rather than Lyman-α lines, then we show how to relate the observed moments of the source magnitude distribution to the mass distribution of absorbers. In order to illustrate the feasibility of the m...

We study the extent and covering fraction of cool baryons around galaxies of different luminosity and mass, based on a survey of Mg II λλ2796,2803 absorption features near known galaxies. The initial sample consists of 13 galaxy and absorber pairs and 10 galaxies that do not produce Mg II absorption lines to within sensitive upper limits. The redshifts of the galaxy and absorber pairs range fro...

The Proca equation with negative mass-square is studied in a refractive and absorptive spacetime. The generation of superluminal radiation fields by subluminal currents is discussed. The possibility of time-symmetric wave propagation is analysed in the context of the Wheeler–Feynman absorber theory; it is shown how advanced modes of the Proca field can be turned into retarded ones in a permeabl...

The design and fabrication of a plasmonic black absorber with almost 100% absorbance spanning a broad range of frequencies from ultraviolet (UV) to the near infrared (NIR) is demonstrated. The perfect plasmonic absorber is achieved by a combination of a metal film with suitable metal/dielectric nanocomposites. Our fabrication technique is simple, versatile, cost-effective, and compatible with c...

car body lightening and crashworthiness are two important objectives of car design. due to their excellent performance, composite materials are extensively used in the car industries. in addition, reducing the weight of vehicle is effective in decreasing the fuel consumption. hat shape energy absorber is used in car’s doors for side impact protection. the aim of these numerical models and exper...

Femtosecond and picosecond operating regimes of an argon-ion-pumped Cr(3+):LiSrAlF(6) laser, passively mode locked using a saturable absorber, are described. At low absorber concentrations, self-starting cw mode locking is demonstrated, which yields pulses as short as 33 fs after extracavity prism compensation. At higher concentrations, both cw mode-locked and Q-switched mode-locked operation i...