Experimental investigation of static properties of magnetorheological elastomer

Magnetorheological elastomer (MRE) is a type of smart material made of natural or synthetic rubber filled with micron-sized magnetic particles. Its shear modulus and elasticity can be controlled by applying an external magnetic field. In this study, a mounting system model is used to obtain displacement transmissibility factor. In the experimental analysis, three different MRE samples are manufactured by varying the percentage of magnetic par- ticles. The experimental investigations are carried out to characterize the quasi-static properties of these MREs by attaching them with universal testing machine in com- pression and tensile mode. In both modes, different cur- rents and velocities are applied to the samples. From the experimental results, a proportional relationship has been observed among the resisting force from MREs and applied excitation current, displacement and velocity. In most cases, the force has increased with the increasing per- centage of magnetic particles in the sample. However, the highest force is obtained from the sample with 30% mag- netic particles, at 2 A current and velocity of 4 mm/min. The results observed in this research would be useful for vibration control in applications such as engine mounting system

Antibiotic therapy of choice for community-acquired pneumonia in Malaysian Hajj pilgrims: the pattern and associated factors

Introduction : Pneumonia is a potentially life-threatening illness that poses global health teething troubles particularly among elderly population and performing Hajj. Empirical antibiotic treatment has been recommended for all suspected community-acquired pneumonia (CAP) patients as initial treatment on admission. Aim of the research : To describe the antibiotic therapy of CAP and determine the associated factors related to the treatment options among Malaysian Hajj pilgrims. Material and methods: This was a cross-sectional study involving 91 patients who were admitted to Tabung Haji Hospital, Makkah in 2012, with the clinical diagnosis of pneumonia during Hajj season. The antibiotic treatment for the patients as well as demographic factors and co-morbidity, which potentially influence the treatment options, were studied. Results : The mean age of the hajj pilgrims was 71.4 ±8.7 years. The most frequently prescribed antibiotic was levofloxacin (44.0%), followed by azithromycin (40.7%), cefuroxime (23.1%), ampicillin + sulbactam (16.5%), and amoxicillin + clavulanate (15.4%). The age of patients was significantly associated with levofloxacin, azithromycin, and meropenem (p = 0.032, 0.028, and 0.026, respectively). Patients with diabetes were statistically significantly highly prescribed with cefuroxime (p = 0.036). Conclusions : Levofloxacin and azithromycin were classified as the most common antibiotic treatment given to Malaysian Hajj pilgrim with CAP and their choice was associated with older age of patients. Otherwise, cefuroxime was the prescription of choice in diabetics

Development of High Entropy Alloy (HEA) as catalyst for Azo dye degradation in Fenton process

Azo dye is widely used in the textile industry since it is cost effective and simple to use . However, it becomes a continuous source of environmental pollution due to its carcinogenicity and toxicity. Various methods had been used to remove the azo dye in solution. One of the famous and repeatedly used is Fenton process. The Fenton’s process is one of the advanced oxidation process where iron catalysed hydrogen peroxide to generate hydroxyl radical. Treating azo dyes in solution requires a catalyst to enhance the process of degradation. Herein, high entropy alloy (HEA) has been proposed as a catalytic material to enhance the performance of Fenton process for azo dye degradation. HEA has been reported as a promising catalyst due to its high surface area. The higher the number of active sites, the higher the rate of azo dye degradation as more active sites are available for adsorption of azo dyes. The results have shown that HEA can be used as a catalyst to fasten the Fenton’s reaction since the degradation time is proven to be shorter in the presence of HEA. The method derived from the result of this study will contribute in treating azo dyes for wastewater management in Fenton process