High performance concrete (HPC) bridge decks are prone to premature cracking if movement is restrained. Internal curing (IC) can reduce shrinkage cracking in concrete structures, thus improving their performance and service life. However, there is very limited information available in the literature on the possible extension of service life due to internal curing. This paper addresses this ques...

plastic shrinkage is one of the most important parameter which must be considered in hot weather concreting. if plastic shrinkage is not prevented, cracking will be significant, especialy if silica fume is used in the mix. in this paper, the effect of silica fume in bleeding and evaporation was investigated in laboratory. the results showed that in restrained shrinkage, beside relative humidity...

two potassium oxalate doped tio2 samples, designated as k1-tio2 and k2-tio2, were synthesized by the base-catalyzed sol-gel process. these samples were impregnated into rubber sheets. two commercial tio2 samples, anatase and degussa p25, were used as reference materials with which the synthesized samples were to be compared. anatase and p25 were also impregnated into rubber sheets and designate...

In situ transmission electron microscopy study of electric field-induced cracking has been conducted on ^001& oriented 0.65Pb~Mg1/3Nb2/3!O3 – 0.35PbTiO3 crystal. Fracture of the 90° domain boundary was directly observed in the tetragonal area under both static and alternating electric fields. The field strength required to induce domain boundary cracking was lower for alternating electric field...

A coupled reactor/furnace simulation has been conducted for a 100 kt/a SL-II naphtha cracking furnace containing both long-flame and radiation burners. The computational fluid dynamics approach was used to simulate the flow, combustion and radiative heat transfer in the furnace. The software packages COILSIM1D and SimCO were used to account for the cracking process in the reactor coils. The sim...

Catalytic cracking of butene to propylene was carried out in a continuous-flow fixed-bed reactor over HZSM-5 catalysts modified by nickel and phosphorus. The structure and acidity of catalysts were measured by N2 adsorption, NH3-TPD and XPS. The results revealed that surface area and strong acid sites both decreased with increasing phosphorus loadings. The increment of phosphorus loadings reduc...

Catalyst layers (4-20 microm) of rhodium (1 wt%) supported on alumina, titania, and ceria-zirconia (Ce(0.5)Zr(0.5)O(2)) were coated on stainless-steel corrugated sheets by dip-coating in very stable colloidal dispersions of nanoparticles in water. Catalytic performances were studied for low-temperature (< or = 500 degrees C) steam reforming of propane at a steam to carbon ratio equal to 3 and l...

Surface reflection can be used as one quality assurance procedure to inspect the defects, cracking, and other irregularities occurring on a polished surface. In this paper, we present a novel approach to the detection of defects based on analysis of surface reflection images. In this approach, the surface image is analyzed using texture analysis based on Gabor-filtering. Gabor-filters can be us...

The filling of strand corrosion products during concrete crack propagation is investigated experimentally in the present paper. The effects of stirrups on the filling of corrosion products and concrete cracking are clarified. A prediction model of crack width is developed incorporating the filling proportion of corrosion products and the twisting shape of the strand. Experimental data on cracki...

This paper presents data from a preliminary investigation on the neurophysiological changes that occur when a person attempts to crack a password. A password cracking scenario was provided to a small cohort of university students and while they were attempting to crack into the password, their EEG was recorded. The results indicate that the overall frontal lobe power (at electrode position F7) ...