Optimization of Laminates for Maximum Buckling Load

Journal of Failure Analysis and Prevention - Objective of this work is to optimize the structural configuration of laminates in terms of design for the maximization of buckling resistance of...     

Experimental investigation on controlled cooling by coupling of thermoelectric and an air impinging jet for CPU

In this study, experimental tests have been carried out on the coupling thermoelectric cooling module with minichannel heatsink subjected to impinging airflow for cooling desktop central processing unit (CPU). A controlled thermoelectric-forced test system was designed for this purpose. This was designed using electronic Arduino card. The proposed hybrid cooling system was compared with the conventional forced air-cooling technique. Three power of heat source (CPU) were adopted, investigated, and compared, namely 60, 87, and 95 W. Performance of controlled thermoelectric cooling with three preset temperature were experimentally examined. The effects of air velocity and thermoelectric input current on the case temperature (T_case), thermal resistance, and heat transfer coefficient were analyzed. Results showed that the T_case increases with the increase of its input power. In addition, increasing air jet velocity and thermoelectric input current improve CPU cooling significantly. For a CPU power of 95 W, the recorded T_case temperature was 57°C with the conventional system. While it was maintained below 50°C in the hybrid system. The thermoelectric cooler has had a major effect on CPU cooling, having 15% improvement over conventional forced air-cooling. However, this was accompanied by an increase in energy consumption in the range of 45 W.     

Feature learning and encoding for multi-script writer identification

International Journal on Document Analysis and Recognition (IJDAR) - Writer identification from handwriting samples has been an interesting research problem for the pattern recognition community in...     

Corrosion inhibition of carbon steel by N,N′-Dimethylaminoethanol in simulated concrete pore solution contaminated with NaCl

The inhibition behavior of N,N′-Dimethylaminoethanol (DMEA) as an organic corrosion inhibitor for carbon steel in simulated concrete pore solution contaminated with chloride ions encountered in the Mediterranean seawater (0.5 mol L^?1), at different temperatures, was investigated by means of weight loss, potentiodynamic polarization and electrochemical impedance spectroscopy (EIS) techniques. The results obtained confirm that DMEA is an efficient corrosion inhibitor over the whole range of temperatures studied; it can significantly reduce the corrosion rate of carbon steel. The inhibition efficiency (IE%) increases as the DMEA concentration rises; it reaches its maximum average value of 80% at about 0.125 mol L^?1. The corrosion inhibition of carbon steel by DMEA occurs through chemisorption of inhibitor molecules on the active sites, according to the Langmuir isotherm; this leads to the formation of a passive layer on the metal surface which separates the metal from direct contact with the corrosive medium and hence keeps the interface in a passive state. Furthermore, the activation parameters of corrosion processes were determined and discussed.     

Effect of temperature and type of sand on the magnesium sulphate attack in sulphate resisting Portland cement mortars

External Sulphate Attack on sulphate-resisting Portland cement concretes is a well-researched field. However, the effect of temperature on the performance of sulphate attack requires further attention. For this purpose, cubic mortars were made with sulphate resisting Portland cement (low C₃A) and two types of sand, silica and limestone, which were then immersed in a 5% MgSO₄ solution at different temperatures: 5, 20 and 50 °C, for 24 months. The deterioration of mortars due to magnesium sulphate attack was evaluated by measuring changes in mass, compressive strength, porosity and sorptivity. The X-ray diffraction was also used to determine the different mineral phases, and the pH of the conservation solutions was monitored. No damage was observed on the samples exposed at 50 °C. However, serious damage was noted on mortars made with silica sand exposed at 5 °C. Results show that high temperature improved some physical and mechanical properties and do not necessarily accelerate the degradation due to magnesium sulphate attack. Sulphate-resisting Portland cements with limited C₃A content was found to be susceptible to Thaumasite Sulphate Attack. The type of sand has a remarkable effect on the performance of mortars at low temperature compared to high temperature. The samples with limestone sand showed better resistance against magnesium sulphate attacks.     

Screening of the most consumed beverages and spices for their bioactive non-nutrient contents

The present research emphasizes on the bioactive non-nutrient components of the frequently consumed food products daily. The most popular beverages (instant, filter and Turkish coffee, green, black, sage, apple, rosehip, linden and fennel tea infusions) and herbal spices (cinnamon thyme, cumin, mint, sweet pepper, chili pepper, sumac, black pepper and clove) were investigated to evaluate the antioxidant capacities of the samples. Amount of total biophenols (TB) and total flavonoids (TF) were measured by Folin–Ciocalteu and Aluminum chloride colorimetric methods, respectively. CUPRAC (The cupric ion reducing antioxidant capacity) assay and DPPH (α, α-diphenyl-β-picrylhydrazyl) free radical scavenging method were applied to determine the antioxidant activity (AA) of the products. Antimicrobial analyses of the samples were also conducted based on in vitro study. Furthermore, the main biophenol of each sample was identified through high performance liquid chromatography (HPLC). The outcome of the present study will be a useful guidance for the researchers looking for the health benefits of these daily consumed food products.