A technique for enhanced generation of selected high harmonics in a gas medium, in a high ionization limit, is proposed in this paper. An aperiodically corrugated hollow-core fiber is employed to modulate the intensity of the fundamental laser pulse along the direction of propagation, resulting in multiple quasi-phase-matched high harmonic emissions at the cutoff region. Simulated annealing (SA...

Double-walled TiO2 nanotubes with porous wall morphologies are fabricated by anodization under ultraviolet (UV) irradiation. TiO2 formed by anodization of Ti is activated to generate electrons and holes by UV and the anodization process is influenced by the photo-generated charges. As a consequence, morphologies of the fabricated TiO2 nanotubes can be adjusted by controlling the UV illumination...

polyvinylidene fluoride/polyvinylpyrrolidone (pvdf/pvp) hollow fiber membranes were fabricated by dry-jet wet-spinning process. the correlated effects of the air gap length and pvp concentration ((1) the air gap length effect at the low and high pvp concentration in the dope solutions, as well as (2) the effect of the pvp concentration at the same air gap length) on the cross-section structure ...

latticed columns are frequently used in industrial steel structures. in some countries these built-up columns might be even used in other types of steel structures such as residential and commercial buildings. besides, latticed columns are parts of skeletons of many historic buildings all around the world. to analyze a steel structure with latticed columns a more accurate numerical model for su...

Wire and arc additive manufacturing (WAAM) has been attracting industrial attention due to its high productivity flexibility. However, fatigue life data of WAAM HSLA steel is scarce. In this study, the mechanical properties thin-walled parts fabricated by were assessed via non-destructive destructive testing, providing a comprehensive analysis on material’s behaviour. The conditions have more p...

geometric and material nonlinear behavior of slender webs in i-column girders having stocky flanges under the action of combined lateral and axial loads is investigated. interaction curves corresponding to the application of compressive and shear loads at buckling and ultimate stages for both web plates and column sections are plotted. in addition, the effects of flange and web slenderness rati...

Southwest Research Institute (SwRI ® ) conducted a study to determine whether pulsed x-ray sources used in conjunction with amorphous silicon real-time imaging plates could provide equivalent radiographs to those obtained using isotopic sources with conventional radiographic film for inspection of schedule 40 steel pipe. Radiographic procedures for the two techniques were developed; test welds ...