The aim of this work is focused on nucleation stages with emphasis on the development of intra-granular ferrite morphologies during isothermal austenite transformation in titanium free micro-alloyed steel. Isothermal treatment was carried out in the temperature range 350 to 600οC. These treatments were interrupted at different times between 2 and 1800 s in order to analyze the evolution of the microstructure. Metallographic evaluation was done by using optical and scanning electron microscopy (SEM) enabled determination of the nucleation onset at all treatments and subsequent on the development of intra-granular ferrite of isothermally treated Ti free micro-alloyed steel. The results show that at high temperatures ( 500  C) polygonal intra-granularly nucleated ferrite idiomorphs, combined with grain boundary ferrite and pearlite were produced and followed by an incomplete transformation phenomenon, At intermediate temperatures (450 and 500  C) an interlocked acicular ferrite (AF) microstructure is produced, and at low temperatures (400 and 350  C) the sheave of parallel acicular ferrite plates, similar to bainitic sheaves but intra-granularly nucleated were observed. In addition to sheaf type acicular ferrite, the grain boundary nucleated bainitic sheaves are observed.

This paper presents the dynamic crushing performance of corrugated composite plate with different profiles. Samples of sinusoidal, square, and triangular corrugated profiles were experimentally tested. They were subjected to axial impact load. A weight of 10.5 kg have been freely dropped from a height of 1m, 2m, and 3m. The idea is to understand the effect of corrugation geometry on energy absorption performance. All specimens have been manufactured by hand lay-up technique using woven roving E-glass fabric and polyester resin with six layers. Similar specimens have been tested before under the effect of quasi-static compression load. Quasi–static testing is simpler and less expensive than dynamic testing and facilities are more readily available. Quasi–static can provide good qualitative assessment as to the trend of different variables upon energy absorption. However, for useful design data, dynamic testing is essential to determine a quantitative measure of energy absorption. Results obtained from dynamic tests conducted showed that corrugation profile has high effect on energy absorption capability. It is also observed that, specimens of square profile recorded the highest capability of energy absorption characteristics compared with sinusoidal and triangular profiles. This result came exactly in conformity with the results of quasi-static load applied on similar specimen that performed in a previous research.

The quality requirements for concrete reinforcement have increased interest in optimizing the mechanical properties of reinforcing bars used for the construction of all types of structures such as buildings, bridges and other constructions. The variability of mechanical properties of reinforcing steel bars manufactured from scrap metals by local manufacturers in Libya have been investigated in this paper. Sydee-Assayh Steel Factory (SASF) is one of the private steel factories established recently in Libya. This factory uses mainly scrap metals as raw material. This was motivated by the fact that it has been noticed that the use of the substandard reinforcing bars in construction industry could lead to collapse of the structures reinforced with these bars in many developing countries. Therefore a series of experimental tests were conducted to find mechanical properties of Sydee-Assyh Steel Factory products. Steel rods samples of 12mm and 14mm diameter were selected randomly and tested. Results found were compared with Libyan specifications (LNS-75) and ASTM standard (A-615), and found almost satisfactory.

Abstract

This paper provides a CFD comparison of tow turbulence modeling approaches (SST) and (K-epsilon), with application to the simulation of a teardrop. As well as, the study investigates and compares among 3 different models in a range these types in order to assess the suitability of CFD for use when calculating drag co-efficient. Moreover, the study focuses on 3 different velocities to be impacted with the drag co-efficient. Whereas, the pressure over the body was used to calculate the drag co-efficient for each of the 3 teardrops shapes.

The purpose of this study is to contribute to the understanding of how BSC is developed and applied in evaluating the performance of The Jumhouria Bank (JB) in Libya. Using the concepts of Kaplan and Norton, and the data made available from the bank, a BSC was derived to measure the performance of the bank between 2007-2010. The analysis assisted the cause-effect relationships between the non-financial, and the financial dimensions of the BSC. Due to lack of research work, in this area, in the banking sector in Libya, this study shall contribute to the knowledge on how banks in Libya may apply the BSC to evaluate their performance, and how they might turn strategic vision into potential performance. The author proposed some future research needs required in this area. The use of the BSC developed here is limited to the bank studied; however, the approach could trigger off reflections among policy makers and other banks to start using the BSC.

We have synthesized graphene oxide using improved Hummer's method in order to explore the potential use of the resulting graphene oxide as a nanocarrier for an active anticancer agent, chlorogenic acid (CA). The synthesized graphene oxide and chlorogenic acid-graphene oxide nanocomposite (CAGO) were characterized using Fourier transform infrared (FTIR) spectroscopy, thermogravimetry and differential thermogravimetry analysis, Raman spectroscopy, powder X-ray diffraction (PXRD), UV–vis spectroscopy and high resolution transmission electron microscopy (HRTEM) techniques. The successful conjugation of chlorogenic acid onto graphene oxide through hydrogen bonding and π–π interaction was confirmed by Raman spectroscopy, FTIR analysis and X-ray diffraction patterns. The loading of CA in the nanohybrid was estimated to be around 13.1% by UV–vis spectroscopy. The release profiles …

This paper presents the mediating effect of information technology (IT) on the relationship between contextual factors and performance of small construction companies. A total of 200 questionnaires were distributed to Malaysian construction firms (G3, G4, and G5). The target respondents were general managers, senior managers, and project managers of construction firms and those who have considerable knowledge of IT implementation in their firms. Sixty-eight completed questionnaires were collected, which indicates a 34% response rate. The three determinants used are the firm contextual factors, IT effectiveness (independent variable), and overall firm performance (dependent variable). The relationship between contextual factors and firm performance was evaluated according to two hypotheses. The first hypothesis suggested a positive relationship between contextual factors and overall firm performance, whereas the second hypothesis suggested a positive relationship between contextual factors and IT effectiveness. IT resource strategy was identified as the most important factor in firm performance. The results indicate a weak positive relationship between contextual factors and overall firm performance. The mediating effects of IT effectiveness on contextual factors and overall firm performance were insignificant.