A Comparative Study on the Flexural Behaviour of Rubberized and Hybrid Rubberized Reinforced Concrete Beams

This paper aims to investigate the flexural behaviour of the rubberized and hybrid rubberized reinforced concrete beams. A total of fourteen beams, 150×200 mm in cross-section with 1000 mm in length, were subject to a laboratory test over an effective span of 900 mm. The sand river aggregate was replaced by 10%, 12.5%, and 15% of crumb rubber (volume).   The hybrid structure contained two double layers: 1) rubberized reinforcement concrete at the top layer of the beam and 2) reinforcement concrete at the bottom layer of the concrete beam. The static responses by the flexural test of all the beams were evaluated in terms of their fresh properties, failure patterns, total energy, flexural strength, stiffness, and ultimate deflection, modulus of rupture, strain capacity, and ductility index. The results showed that there were improvements when the hybrid beams were used in most cases such as failure pattern, ultimate load, stiffness, modulus of rupture, and stress. The rubberized concrete beams showed improvements in the strain capacity as illustrated in strain gauges and stress-strain curves, toughness, ultimate deflection, and ductility index. The findings of the study revealed an improved performance with the use of the hybrid beams. This has resulted in the implementation of innovative civil engineering applications in the engineering sustainable structures

The role of the public accounts committee in enhancing government accountability in Malaysia

This chapter provides an overview of the institutional framework of Malaysia's federal Public Accounts Committee (PAC), and the Committee's role in enhancing public sector accountability. The development of the PAC and its relationship to the government structure in Malaysia are discussed alongside other institutions within the administrative framework of accountability. These include the Accountant General's Department and the National Audit Department. A description of the PAC's powers, responsibilities, membership and working practices precedes a discussion on its effectiveness in supporting the enhancement of accountability. In addition, this chapter also cites cases examined by the PAC that were highlighted in the media

A Flood Risk Management Program of Wadi Baysh Dam on the Downstream Area: An Integration of Hydrologic and Hydraulic Models, Jizan Region, KSA

For public safety, especially for people who dwell in the valley that is located downstream of a dam site, as well as the protection of economic and environmental resources, risk management programs are urgently required all over the world. Despite the high safety standards of dams because of improved engineering and excellent construction in recent times, a zero-risk guarantee is not possible, and accidents can happen, triggered by natural hazards, human actions, or just because the dam is aging. In addition to that is the impact of potential climate change, which may not have been taken into account in the original design. A flood risk management program, which is essential for protecting downstream dam areas, is required. Part of this program is to prepare an inundation map to simulate the impact of dam failure on the downstream areas. The Baysh dam has crucial importance both to protect the downstream areas against flooding, to provide drinking water to cities in the surrounding areas, and to use the excess water for irrigation of the agricultural areas located downstream of the dam. Recently, the Kingdom of Saudi Arabia (KSA) was affected by extraordinary rainstorm events causing many problems in many different areas. One of these events happened along the basin of the Baysh dam, which raised the alarm to the decision makers and to the public to take suitable action before dam failure occurs. The current study deals with a flood risk analysis of Wadi Baysh using an integration of hydrologic and hydraulic models. A detailed field investigation of the dam site and the downstream areas down to the Red Sea coast has been undertaken. Three scenarios were applied to check the dam and the reservoir functionality; the first scenario at 100-and 200-year return period rainfall events, the second scenario according to the Probable Maximum Precipitation (PMP), and the third scenario if the dam fails. Our findings indicated that the Baysh dam and reservoir at 100-and 200-year rainfall events are adequate, however, at the PMP the water will spill out from the spillway at ~8900 m3/s causing flooding to the downstream areas; thus, a well-designed channel along the downstream wadi portion up to the Red Sea coast is required. However, at dam failure, the inundation model indicated that a vast area of the section downstream of the dam will be utterly devastated, causing a significant loss of lives and destruction of urban areas and agricultural lands. Eventually, an effective warning system and flood hazard management system are imperative

METHOD DEVELOPMENT AND VALIDATION OF THE CHROMATOGRAPHIC ANALYSIS OF FLUTICASONE PROPIONATE AND SALMETEROL XINAFOATE COMBINATION IN SOLUTIONS AND HUMAN PLASMA USING HPLC WITH UV DETECTION

Objective: A simple, Rapid, and sensitive HPLC method utilizing UV detection was developed and validated for the simultaneous estimation of Fluticasone propionate (FP) and Salmeterol xinafoate (SX) in solutions and in vitro human plasma. Methods: Chromatographic analysis was done on SUPELCO® RP-C18 column (150 x 4.6 mm, 5 μm particle size) with an isocratic mobile phase composed of methanol, acetonitrile, and water (50:20:30, v/v) mixture while flow rate was set to 1 ml/min. Detection with UV at maximum absorbance wavelength (ʎmax) values of 236 and 252 for FP and SX, respectively. Spiked plasma samples were liquid-liquid extracted by diethyl ether and reconstituted using methanol. Results: Method was accurate and precise over a linear (R2>0.995) range of (0.067-100 µg/ml) and (0.0333-50 µg/ml) for FP and SX, respectively. LOD/lOQ values were 0.13/0.6 and 0.06/0.3 µg/ml for FP and SX, respectively. The developed method was successfully applied for the analysis of FP and SX in spiked human plasma samples. The method is considered to be accurate and precise over a linear (R2>0.9969) range of (6.67-66.67 µg/ml) and (3.33-33.3 µg/ml) for FP and SX, respectively. Extraction efficiency was approved by recovery values of (94.98–102.46 %) and (96.54–102.62 %) for FP and SX, respectively. Conclusion: This validated method revealed simple and cheap extraction procedures and detectors, non-buffered mobile phase, and short retention times with excellent resolution

Design and numerical investigation of cadmium telluride (CdTe) and iron silicide (FeSi2) based double absorber solar cells to enhance power conversion efficiency

Inorganic CdTe and FeSi2-based solar cells have recently drawn a lot of attention because they offer superior thermal stability and good optoelectronic properties compared to conventional solar cells. In this work, a unique alternative technique is presented by using FeSi2 as a secondary absorber layer and In2S3 as the window layer for improving photovoltaic (PV) performance parameters. Simulating on SCAPS-1D, the proposed double-absorber (Cu/FTO/In2S3/CdTe/FeSi2/Ni) structure is thoroughly examined and analyzed. The window layer thickness, absorber layer thickness, acceptor density (NA), donor density (ND), defect density (Nt), series resistance (RS), and shunt resistance (Rsh) were simulated in detail for optimization of the above configuration to improve PV performance. According to this study, 0.5 um is the optimized thickness for both the CdTe and FeSi2 absorber layers in order to maximize efficiency. Here, the value of the optimum window layer thickness is 50 nm. For using CdTe as a single absorber, the efficiency is achieved by 13.26%. But for using CdTe and FeSi2 as a dual absorber, the efficiency is enhanced and the obtaining value is 27.35%. The other parameters are also improved and the obtaining values for fill factor (FF) are 83.68%, open-circuit voltage (Voc) is 0.6566V, and short circuit current density (JSc) is 49.78 mA/cm2. Furthermore, the proposed model performs good at 300 K operating temperature. The addition of the FeSi2 layer to the cell structure has resulted in a significant quantum efficiency (QE) enhancement because of the rise in solar spectrum absorption at longer wavelengths. The findings of this work offer a promising approach for producing high-performance and reasonably priced CdTe-based solar cells.Comment: 17 pages, 10 figure

Synthesis and Antioxidant Activities of Novel 5-Chlorocurcumin, Complemented by Semiempirical Calculations

The novel curcumin derivative (1E,4Z,6E)-5-chloro-1,7-bis(4-hydroxy-3-methoxyphenyl)hepta-1,4,6-trien-3-one (5-chlorocurcumin) was prepared from natural curcumin. The newly synthesised compound was characterised by spectral studies (IR, 1H NMR, and 13C NMR). The free radical scavenging activity of 5-chlorocurcumin has been determined by measuring interaction with the stable free radical DPPH, and 5-chlorocurcumin has shown encouraging antioxidant activities. Theory calculations of the synthesised 5-chlorocurcumin were performed using molecular structures with optimised geometries. Molecular orbital calculations provided a detailed description of the orbitals, including spatial characteristics, nodal patterns, and the contributions of individual atoms

Evaluation of female Aedes aegypti proteome via LC-ESI-MS/MS using two protein extraction methods

Background Proteomic analyses have broadened the horizons of vector control measures by identifying proteins associated with different biological and physiological processes and give further insight into the mosquitoes’ biology, mechanism of insecticide resistance and pathogens-mosquitoes interaction. Female Ae. aegypti ingests human blood to acquire the requisite nutrients to make eggs. During blood ingestion, female mosquitoes transmit different pathogens. Therefore, this study aimed to determine the best protein extraction method for mass spectrometry analysis which will allow a better proteome profiling for female mosquitoes. Methods In this present study, two protein extractions methods were performed to analyze female Ae. aegyti proteome, via TCA acetone precipitation extraction method and a commercial protein extraction reagent CytoBusterTM. Then, protein identification was performed by LC-ESI-MS/MS and followed by functional protein annotation analysis. Results The CytoBusterTM reagent gave the highest protein yield with a mean of 475.90 µg compared to TCA acetone precipitation extraction showed 283.15 µg mean of protein. LC-ESI-MS/MS identified 1,290 and 890 proteins from the CytoBusterTM reagent and TCA acetone precipitation, respectively. When comparing the protein class categories in both methods, there were three additional categories for proteins identified using CytoBusterTM reagent. The proteins were related to scaffold/adaptor protein (PC00226), protein binding activity modulator (PC00095) and intercellular signal molecule (PC00207). In conclusion, the CytoBusterTM protein extraction reagent showed a better performance for the extraction of proteins in term of the protein yield, proteome coverage and extraction speed