A non-plasticized chitosan based solid state electrode for flow injection analysis of glutamate in food samples

This report describes the development of solid state glutamate sensor based on chitosan. The electrode has linearity range of 0.01–1 mM glutamate with detection limit of 0.008 mM. The presence of other conventional food additives at physiological level does not interfere. The interfering effect is, however, minimized through prior dilution of the sample. Recovery values of 88.9–99.2% are obtained throughout. The proposed electrode has been applied in flow injection analysis (FIA) glutamate in food samples. In the validation experiment, the proposed electrode is found to be comparable with the standard method.     

A novel dengue fever (DF) and dengue haemorrhagic fever (DHF) analysis using artificial neural network (ANN)

Dengue fever (DF) is an acute febrile viral disease frequently presented with headache, bone or joint and muscular pains, and rash. A significant percentage of DF patients develop a more severe form of disease, known as dengue haemorrhagic fever (DHF). DHF is the complication of DF. The main pathophysiology of DHF is the development of plasma leakage from the capillary, resulting in haemoconcentration, ascites, and pleural effusion that may lead to shock following defervescence of fever. Therefore, accurate prediction of the day of defervescence of fever is critical for clinician to decide on patient management strategy. To date, no known literature describes of any attempt to predict the day of defervescence of fever in DF patients. This paper describes a non-invasive prediction system for predicting the day of defervescence of fever in dengue patients using artificial neural network. The developed system bases its prediction solely on the clinical symptoms and signs and uses the multilayer feed-forward neural networks (MFNN). The results show that the proposed system is able to predict the day of defervescence in dengue patients with 90% prediction accuracy.     

Ethanol and lactic acid production using sap squeezed from old oil palm trunks felled for replanting

Old oil palm trunks that had been felled for replanting were found to contain large quantities of high glucose content sap. Notably, the sap in the inner part of the trunk accounted for more than 80% of the whole trunk weight. The glucose concentration of the sap from the inner part was 85.2 g/L and decreased towards the outer part. Other sugars found in relatively low concentrations were sucrose, fructose, galactose, xylose, and rhamnose. In addition, oil palm sap was found to be rich in various kinds of amino acids, organic acids, minerals and vitamins. Based on these findings, we fermented the sap to produce ethanol using the sake brewing yeast strain, Saccharomyces cerevisiae Kyokai no.7. Ethanol was produced from the sap without the addition of nutrients, at a comparable rate and yield to the reference fermentation on YPD medium with glucose as a carbon source. Likewise, we produced lactic acid, a promising material for bio-plastics, poly-lactate, from the sap using the homolactic acid bacterium Lactobacillus lactis ATCC19435. We confirmed that sugars contained in the sap were readily converted to lactic acid with almost the same efficiency as the reference fermentation on MSR medium with glucose as a substrate. These results indicate that oil palm trunks felled for replanting are a significant resource for the production of fuel ethanol and lactic acid in palm oil-producing countries such as Malaysia and Indonesia.     

A fast-lock delay-locked loop architecture with improved precharged PFD

In this paper, a dual charge pump architecture for fast-lock delay-locked loop (DLL) is proposed and analyzed. The proposed fast lock DLL uses only one phase frequency detector (PFD) to perform dual path tuning and a lock control circuit to control the switching between the two path. An improved PFD is proposed to reduce the output jitter by reducing the one-shot pulse produced when the reference signal and feedback signal is in phase. The proposed DLL circuit is designed based on the Silterra 0.18-μm 1P6M CMOS process with a 1.8-V supply voltage. The active area of the proposed DLL circuit is 327.46 × 116.16 μm. An experimental chip was implemented and measured. The measurement results show that the proposed DLL has fast locking properties.     

Current scenario and potential of biodiesel production from waste cooking oil in Pakistan: An overview

Biodiesel utilization has been rapidly growing worldwide as the prime alternative to petrodiesel due to a global rise in diesel fuel demand along with hazardous emissions during its thermochemical conversion. Although, several debatable issues including feedstock availability and price, fuel and food competition, changes in land use and greenhouse gas emission have been raised by using edible as well as inedible feedstocks for the production of biodiesel. However, non-crop feedstocks could be a promising alternative. In this article, waste cooking oils have been recommended as a suitable option for biodiesel production bearing in mind the current national situation. The important factors such as the quantity of waste cooking oil produced, crude oil and vegetable oil import expenses, high-speed diesel imports, waste management issues and environmental hazards are considered. Moreover, process simulation and operating cost evaluation of an acid catalyzed biodiesel production unit are also conducted. The simulation results show that the production cost of waste cooking oil-based biodiesel is about 0.66USD·L^-1. We believe that the present overview would open new pathways and ideas for the development of biofuels from waste to energy approach in Pakistan.     

Catalytic co-gasification of coconut shells and oil palm fronds blends in the presence of cement,dolomite, and limestone: Parametric optimization via Box Behnken Design

In this study, Response Surface Methodology (RSM) in combination with Box-Behnken Design (BBD) was used to optimize the temperature, catalyst loading, and blending ratio for a co-gasification process. The catalytic co-gasification of coconut shells (CS) and oil palm fronds (OPF) blends was performed in the presence of cement, dolomite, and limestone catalysts. A combined effect of temperature, catalyst loading, and blending ratio on production of H₂, CO, and tar formation was investigated by using a BBD approach. The results showed the strongest influence of the process temperature on H₂ and CO yield, and tar formation followed by the catalyst loading and blending ratio. A catalyst loading of 30 wt%, process temperature of 900 °C and blending ratio of CS50:OPF50 were predicted as the optimized conditions for the reported co-gasification results. The highest H₂ yield of 20.64 vol% was produced during catalytic co-gasification of the blended biomass with limestone followed by the cement (18.22 vol%) and dolomite (14.99 vol%). Under optimized process conditions, lowest tar concentration of 0.87 g/Nm³ was obtained with limestone follow by the cement (1.42 g/Nm³) and dolomite (2.13 g/Nm³). However, blending ratio did not affect H₂, CO yield, and tar formation appreciably. Conclusively, the mixing ratio of CS and OPF would have a negligible role in controlling the process output.     

Evaluation on some finishing properties of oil palm plywood

Oil palm is the largest and most important plantation crop in Malaysia. The oil palm generally lasts for 25–30 years before the next replantation is done. Substantial amount of biomass in the form of palm trunk results from plantation cycle. This resource is simply left on the ground to decay and is not used as raw material to manufacture any kind of value-added products. The objective of this study was to investigate the possibility of manufacturing plywood from oil palm trunks and to evaluate some of the finishing properties of such experimental panels in comparison to those from Shorea sp as control samples. Three-ply plywood samples were produced from 5 mm thick veneers of oil palm using urea formaldehyde adhesive. Three types of chemicals, namely nitrocellulose, pre-catalyzed lacquer and polyurethane were used to finish experimental panels. The surface finished with nitrocellulose had the lowest contact angle on raw surface of oil palm plywood and wood. The average cross cut tape index of oil palm plywood was comparable to Shorea sp. All finishing materials of oil palm plywood produced impact rating of 4 except for surface finished with nitrocellulose while finishing on wood indicated an impact rating of 3. Oil palm plywood had higher weight loss compared to Shorea sp. Based on results from contact angle, cross cut tape index, impact rate test, weathering, and soil burial test methods it appears that the samples showed acceptable finishing properties comparable to those of solid wood.