The aim of this study is to investigate the problem pipe cracking based on T-stress analysis and influence other parameters, using a numerical computation performed by extended isogeometric (X-IGA). This article examines T-stress, which defines second term Williams’ series expansion. provides effective elastic modeling at crack tip. Using iso-geometric (X-IGA), we determined distribution tip in...

Allothermal cracking of methane is a suitable and eco-friendly way to simultaneously produce hydrogen and carbon black. The economic viability of the process relies on the ability to produce carbon black having well-defined characteristics, particularly concerning the particle size. A model for the study of the carbon particle size distribution during thermal cracking of methane has been develo...

In this study, the flexural behavior of ultra-high-performance fiber-reinforced concrete (UHPFRC) is examined as a function of fiber length and volume fraction. Straight steel fiber with three different lengths (lf) of 13, 19.5, and 30 mm and four different volume fractions (vf) of 0.5%, 1.0%, 1.5%, and 2.0% are considered. Test results show that post-cracking flexural properties of UHPFRC, suc...

A two-dimensional thermal elasto-plastic numerical model is developed by finite element method to analyze and compare the mechanical driving factor for heat affected zone (HAZ) liquation cracking during laser welding and hybrid laser-arc welding techniques. Calculations of transient temperatures and cooling rates are used in conjunction with solidification theory to analyze weld pool characteri...

This paper described the discovering process of some shortcomings of the conventional fluid catalytic cracking (FCC) process and the proposed two-stage riser (TSR) FCC process for decreasing dry gas and coke yields and increasing light oil yield, which has been successfully applied in 12 industrial units. Furthermore, the multifunctional two-stage riser (MFT) FCC process proposed on the basis o...

The kinetics of palm oil catalytic cracking over aluminum containing mesoporous silica Al-MCM-41 (5% Al) was investigated in a batch autoclave reactor at the temperatures range of 573 – 673 K. The catalyst was prepared by using sol-gel technique and has been characterized by nitrogen adsorption and x-ray diffraction methods. Surface area of 1276 m/g with average pore diameter of 2.54 nm and por...

This report describes the details of two new proof-of-concept Bluetooth security analysis tools and two new attacks against Bluetooth security. On-Line PIN Cracking script is a security analysis tool for on-line Bluetooth device PIN cracking. Brute-Force BD ADDR Scanning script is a security analysis tool for brute-force discovery of the addresses of Bluetooth devices that want to be private. S...

In a remarkable series of experiments, Elssner et al. (1994) and Korn et al. (2002) observed cleavage cracking along a bimaterial interface between Nb and sapphire. The stress required for cleavage cracking is around the theoretical strength of the material. Classical plasticity models fall short to reach such a high stress level. We use the conventional theory of mechanism-based strain gradien...

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...