A review on conversion of triglycerides to on‐specification diesel fuels without additional inputs

Dependence on fossil fuels for global energy supply has continued to generate concerns about climate change and sustainable development. It has motivated the search for carbon‐neutral alternative resources for the production of transportation fuels to replace crude oil. Although biodiesels have recently emerged as a close substitute to petrol diesel, their use in compression ignition engines designed to run on petro‐diesel fuels are linked to adverse effects on the engines' performance and life span. This informed efforts at upgrading biodiesel or direct conversion of triglycerides to hydrocarbon mixtures that are identical or similar to that of petro‐diesel through hydrodeoxygenation. Moreover, it seems that commercial methods for the conversion of triglycerides to diesel fuels depends on inputs (methanol and hydrogen) derived from fossil fuels. However, it will be desirable to do so without inputs from fossil fuels. Hence, reaction paths for direct conversion of triglycerides to on‐specification hydrocarbons fuels without hydrogen gas input are discussed and suggested strategies are in cognisance of green chemistry principles. Copyright © 2012 John Wiley & Sons, Ltd.     

Microencapsulation of α-Amylase by Carrying Out Complex Coacervation and Drying in a Single Step Using a Novel Three-Fluid Nozzle Spray Drying

The aim of this research was to develop an enzyme encapsulation process in which both the complex coacervation and drying processes are combined into a single step. For this purpose, we used a novel three-fluid nozzle at the atomization step of spray drying. α-Amylase as a model enzyme was encapsulated by coacervation in calcium (Ca) alginate and Ca-alginate + chitosan shell matrices and the powder was obtained in a single step through spray drying. The single-step process was compared to carrying out the complex coacervation and drying processes in two steps using freeze drying, in which α-amylase was encapsulated by carrying out the complexation process in the above-mentioned shell matrices using the same three-fluid atomizer and collecting the coacervates, which were subsequently freeze dried. The results showed that the microcapsules obtained from the single-step encapsulation process (three-fluid nozzle spray drying) had smaller particle sizes, were less porous, and provided better enzyme stability compared to the microcapsules obtained by carrying out the complexation and drying in two steps and the single-step process was faster. It was observed that the egg-box structure was formed in both types of powder particles; however, the complexation with chitosan partially disrupted the formation of this structure. The three-fluid nozzle–based spray drying is a promising technology in which both the complex coacervation and drying processes can be carried out in a single step.     

Evaluation of the Effectiveness of Water Management Policies in Bangladesh

Water resources development and management policies initiatives in Bangladesh are primarily driven by the need for sufficient food grain production for the country's teeming population and curtailing the perennial flooding problems. It is therefore necessary to investigate whether or not these objectives are being met. The aim of this study is to evaluate the impacts of past water resources development and management strategies on agriculture, food security, flood management and socio-economic development in Bangladesh. The research is based on the historical data of the relevant parameters of the water resources management over the period 1947–2005. The outcomes of the study demonstrate that past policies and strategies of water development have resulted in significant irrigation expansion, especially through intensified groundwater utilization, which has helped to achieve the country's primary objective of self-sufficiency in food production. However, the provision of safe drinking water and sanitation facilities still remains a challenge in the country. Similarly, the impact of the flood control policies was diverse with success mostly apparent with regard to protection against modest events, while catastrophic, extreme events still effectively defying answer.     

Fluid flow characterization with tube viscometer data

Pressure gradients and the corresponding mass flow rates of five different non-Newtonian fluid foods: 1% solutions of sodium alginate and CMC, 1.5% CMC solution, two different tomato ketchups, oyster sauce, in four different diameter stainless steel tubes ranging from 7.51 to 16.34 mm i.d. were recorded using a tube viscometer capable of operating in both transient and continuous flow modes. The flow was confined to the laminar flow regime and appreciable slippage occurred in all cases. Power law parameters for the tube flow obtained from the plots of wall shear stress versus apparent wall shear rate are presented for various time-independent fluids in different diameter tubes in original and slip-corrected forms. Such experimental data should prove useful in developing an understanding of flow characterization of non-Newtonian fluids.     

Generalized form of optimal teleportation witnesses

We propose a generalized form of optimal teleportation witness to demonstrate their importance in experimental detection of the larger set of entangled states useful for teleportation in higher dimensional systems. The interesting properties of our witness reveal that teleportation witness can be used to characterize mixed state entanglement using Schmidt numbers. Our results show that while every teleportation witness is also a entanglement witness, the converse is not true. Also, we show that a hermitian operator is a teleportation witness iff it is a decomposable entanglement witness. In addition, we analyze the practical significance of our study by decomposing our teleportation witness in terms of Pauli and Gell-Mann matrices, which are experimentally measurable quantities.     

Screening selected strains of probiotic lactic acid bacteria for their ability to produce biogenic amines (histamine and tyramine)

The aim of this study was to investigate the production of biogenic amines (BA), histamine and tyramine by some probiotic lactic acid bacteria (LAB). Fifteen strains representing six LAB species were screened qualitatively by growing them in a decarboxylase medium. Quantitative analysis was carried out by HPLC analysis with direct derivatization of acid extracts. Lactobacillus casei (TISTR 389) and Lactobacillus delbrueckii subsp. bulgaricus (TISTR 895) were found to produce BA. The highest levels of histamine (1820.9 ± 3.5 mg L^?1) and tyramine (5486.99 ± 47.6 mg L^?1) formation were observed for the TISTR 389 strain, while TISTR 895 produced only histamine (459.1 ± 0.63 mg L^?1) in the decarboxylase broth. Biogenic amine potential was not observed for the Lactobacillus acidophilus, Lactobacillus lactis subsp. lactis, Lactococcus lactis subsp. lactis, and Lactobacillus plantarum strains studied. This study confirmed that BA formation is strain dependent and not related to the species. Therefore, careful screening for amino acid decarboxylase activity is recommended before selecting LAB as appropriate starter or probiotic strains in food and dairy industry.     

Kinetics and Reactor Modeling of Hydrogen Production from Glycerol via Steam Reforming Process over Ni/CeO2 Catalysts

As a result of skyrocketing prices, environmental concerns and depletion associated with fossil fuels, renewable fuels are becoming attractive alternatives. In this respect, the demand for biodiesel has increased tremendously in recent years. Increased production of biodiesel has resulted in a glut of glycerol that has reduced the demand for this once valuable commodity. Consequently, finding alternative uses for glycerol is a timely proposition. One alternative is producing renewable hydrogen from this cheap commodity. Only a handful of studies have been conducted on producing hydrogen from glycerol. Previous studies have mainly focused on finding effective catalysts for glycerol steam reforming. This paper extends previous knowledge by presenting kinetic parameters in relation to glycerol steam reforming over Ni/CeO₂ and a reactor modeling. The study found that the activation energy and the reaction order for the glycerol steam reforming reaction over Ni/CeO₂ catalyst were 103.4 kJ/mol and 0.233, respectively.