Laboratory Characterization of Asphalt Binders Modified with Styrene Butadiene Rubber (SBR)

The study describes the laboratory assessment (physical and rheological properties) of the binders (PG 64-22 and PG 76-22) modified with Styrene Butadiene Rubber (SBR), and a comprehensive comparison between these two modified binder types. PG 64-22 and PG 76-22 were used as base binders. Both of the base binders were blended with SBR at four different percentages of content (0%, 4%, 6%, and 8% by the weight of the binder). The base and modified binders were artificially short-term and long-term aged using a rolling thin film oven (RTFO) and pressure aging vessel (PAV) procedures. Superpave binder tests were conducted on the SBR modified binder using rotational viscometer (RV), dynamic shear rheometer (DSR), and bending beam rheometer (BBR). In depth rutting performance was investigated using Multiple Stress Creep Recovery (MSCR). The results of this study indicated that (1) the addition of SBR into both binders increased the viscosity and polymer modified asphalt (PMA) binders observed to have more significant effect on its viscosity property; (2) the higher the SBR content, the better the rutting resistance of the binder and it is observed that the effect is prominent on the control binder; (3) MSCR test results showed that the SBR modified binders improved the binder percentage recovery and found to have a more significant effect on the PG 76-22 binder compared to PG 64-22; and (4) both the control PG 64-22 and PMA PG 76-22 binders resulted in similar trends on the cracking properties and were found to have insignificant effects due to the addition of an SBR modifier.

Influence of thermal radiation on singular behavior of the Universe

Cosmological models with inhomogeneous viscous fluids with a logarithmic equation of state in the Friedmann-Lemaitre-Robertson-Walker universe are considered. The influence of thermal effects caused by Hawking radiation on the visible horizon of the Universe on the change in the type of singularity of the dark Universe is investigated. It is shown that under the influence of thermal radiation, taking into account the viscosity property of a dark fluid, a qualitative change in the type of the Big Rip singularity is possible, which can lead to the absence of a singularity in the Universe at all.

Preparation of oxidized corn starch in dry method assisted by kneader

In this study, oxidized starch (OCS) with different carboxyl content was prepared by the dry method, with H2O2 as the oxidant and CuCl2 as the catalyst. The optimum conditions were obtained by an orthogonal experiment, under the carboxyl and carbonyl content of 0.6813 and 1.0416% respectively. Fourier transform infrared (FTIR) spectroscopy, X-ray diffraction and gel permeation chromatography characterized the structures of OCS, and the thermal, gelatinization, viscosity property and its viscosity stability were measured. The results demonstrated that the crystallinity decreased slightly and the A-type crystal remained unchanged after oxidation, and the molecular weight of OCS decreased greatly. The thermal decomposition temperature, apparent viscosity and setback viscosity also decreased. With the increase of carboxyl content in OCS, the cold-water solubility and paste transparency of OCS paste increased gradually, while the viscosity of OCS paste decreased, and the viscosity stability displayed a trend of first increasing and then reducing. The OCS obtained by a kneader had low solution viscosity and high viscosity stability, suitable for sizing high count warp yarns.

Study on Ultrafine Particles Used in Drilling Fluids

In this paper, several ultrafine particles were prepared and characterized, then the performance of drilling fluids were evaluated after ultrafine particles were added in water base drilling fluids. The viscosity property of drilling fluids were increased, however, filtration reduction could not be strictly controlled. All filtration volume was difficult to control just like common ultrafine calcium carbonate unless some polymers could be used. Titanium dioxide and zinc dioxide could be used as substitutes of calcium carbonate in drilling fluids.

INFLUENCE OF BIODIESEL AND BLENDED FUELS ON THE TENSILE AND COMPRESSIVE PROPERTIES OF GLASS FIBRE REINFORCED EPOXY COMPOSITES

With the recent usage increase of biodiesel as an alternative fuel source as well as the increase in the utilisation of glass fibre reinforced polymer (GFRP) as structure such as tanks have considerably affected the necessity to study the influence of fuel absorption on the mechanical properties of GFRP composites. Biodiesel is a renewable, efficient and environmentally friendly but possess a high viscosity property. Three main fuel types which consist of aviation fuel, biodiesel and a blend between aviation and biodiesel fuel are used to perform complete immersion of the GFRP specimens. An experimental method is used to investigate the mechanical degradation in term of tension and compression properties of the GFRP composites. The GFRP specimens are aged using immersion bath technique. Vacuum assisted resin transfer moulding (VARTM) is used to manufacture the GFRP specimens with a volume fraction of 0.50 with a void content below 3%. The GFRP specimens were immersed in the fuels until it reaches an equilibrium state before the tensile and compression test was carried out to study the mechanical properties of the immersed specimens. Based on the result obtained, the GFRP specimens that were immersed in all three fuel solution display a slight degradation in term of tensile and compressive strength as well as their Young’s modulus when compared to an as-received (standard) specimen. It is concluded, that the GFRP composite was able to resist the fuels corrosive nature as they can retain most of their mechanical strength and the decrement is not significant.

Gel Formulation of Ethyl Acetate Garlic Extraction and Its Activity Against Staphylococcus Epidermis

Garlic is known to have antibacterial and antifungal activities. This research aims to formulate the gel materials extracted from the garlic and to investigate the antimicrobial activities to Staphylococcus epidermidis. The phytochemical screening showed that the gel materials of ethyl acetate consisted alkaloid, flavonoid, and saponin substances. The formulation of gel was synthesized with different variations of 1, 5, and 10%. In this research, the gel materials were analyzed to understand the stability, homogeneity, pH, viscosity and dispersive powers. The results showed that good abilities of gel based on the taste, aroma and consistency, while the homogeneity property of each samples is influenced by the presence of gel concentration. The viscosity property of gels accounted for 3201.02-1664.04 Cps with 2.95-3.8 cm of dispersive powers. The ability of antimicrobial showed that higher concentration of 5% and 10% gels showed greater inhibitory zones of 18,10 and 22,08 mm compared to 1% of concentration