Rejuvenators have been utilized to restore the physical and rheological properties of aged asphalt binders found in the reclaimed asphalt pavement (RAP). Also, the rejuvenators are utilized to enhance the cracking resistance of asphalt containing RAP. In addition, polymers have been efficiently applied to enhance the rutting performance of rejuvenated mixtures. The purpose of this study was to assess the influence of combining SBS copolymers and aromatic oil (AO) at the same time as a hybrid rejuvenator (HR) on the performance of high RAP asphalt binders and mixtures. HR is a mixture of 25% SBS and 75% AO. The properties of the rejuvenated binders were assessed by SARA (Saturates, Asphaltene, Resin, and Aromatics) fractions analysis, Fourier Transform Infrared Spectrum (FTIR), physical tests, high-temperature storage stability test, Dynamic Shear Rheometer (DSR) test, and Bending Beam Rheological (BBR) test. In addition, the mechanical behaviour of the rejuvenated mixtures was assessed using the Indirect Tensile Strength (ITS) test, moisture susceptibility test, resilient modulus test, and wheel tracking rutting test. The results showed that appropriate adjustment of the SARA fractions and SBS copolymer could improve the overall performance of mixtures and binders with high RAP content. However, it is asserted that a field investigation of this compound rejuvenator should be done to further analyze its influence on the long-term field behavior of high RAP mixtures.

A specific and sensitive thin layer chromatographic method coupled with fluorescence detection for determination of flibanserin (FLN) that treats woman hypoactive sexual desire disorder was developed. The proposed method depends on the enhancement of FLN native fluorescence intensity via the exposure of the developed TLC plate to concentrated hydrochloric acid vapors. Herein, an evaporation setup needed for HCl vapors exposure step was designed for the first time to ensure a uniform distribution of the vapors throughout the developed bands on the plate. Chloroform: methanol (9.5: 0.5, v/v) was the optimum mobile phase that gave a compact band (R_f= 0.44 ± 0.02) using TLC aluminium plates precoated with silica gel G 60F₂₅₄ as a stationary phase. After exposure of the developed TLC plate to HCl vapors, the FLN bands emission intensities were measured after excitation at 275 nm. Conferring ICH …

Curved girders are widely used in bridge construction to overcome geographical obstacles. In such cases, girders with a box cross-section are preferred due to their large flexural and torsional rigidity. Internal diaphragms are used to limit cross-section distortion and the distortional warping stress induced in the box girders. However, the use of such diaphragms hinders girder maintenance. To facilitate the maintenance process, typical cross frames such as X- or V-shape truss members are used. Alternatively, access holes are provided in the solid plate diaphragms. In this paper, finite element models for horizontally curved box girders were constructed and topology optimization method was used to obtain the optimal shapes for the internal and external diaphragms. In this analysis the optimization objective was set to reduce the diaphragm mass while maximizing its rigidity. The mass retained percentage was assigned to various values from 20% to 40%. The deformations and distortional stresses induced in the girders were compared between girders having solid plate diaphragms and girders with optimized cross-frame diaphragms. The parametric study included the cross-section aspect ratio and curved girder central angle as they have large effect on distortional warping stresses. The results showed that the increase in distortional warping normal stress was less than 4% and the increase in the cross-section distortion angle was less than 37% between optimized diaphragms and solid plate diaphragms. The optimized diaphragms were then simplified into more practical configurations that differed depending on the girder aspect ratio. The simplified diaphragms were then tested against the optimized diaphragms for girders with different numbers of internal diaphragms to check its practicality.