Employing an intelligence model and sensitivity analysis to investigate some physicochemical properties of coated bell pepper during storage

The objectives of this work were to study the effects of three different coatings (gum Tragacanth, sesame oil and gum Tragacanth–sesame oil), temperature and time on shelf life of bell pepper. Moisture reduction, shrinkage as well as firmness and colour changes were studied during 30 days at 4, 10, 15 and 23 °C. Results of this study showed that bell peppers treated with gum Tragacanth at higher temperatures, such as 10 °C, had good quality up to 30 days of storage. However, sharp changes in physicochemical characters were observed in bell peppers stored at 23 °C. In order to predict moisture reduction, shrinkage, firmness and colour changes genetic algorithm–artificial neural network model was developed. It was found that artificial neural network with eight hidden neurons truly could predict the physicochemical changes of bell pepper during storage (R² > 0.9598). The results of sensitivity analysis showed that shrinkage percentage and also changes of firmness and colour were very sensitive to storage time, while storage temperature had the most effect on moisture reduction.     

Maximum allowable fouling detection in industrial fired heater furnaces

Journal of Mechanical Science and Technology - Fouling is one the most serious problems in refineries that can have irreparable consequences. In this study, fouling detection inside the tubes in...     

Modelling and optimisation of biomass supply chains: a review

A growing number of researchers are attracted by the domain of bioenergies, due to the problems induced by greenhouse gas emissions and increasing energy demand. One possible way of producing biofuels in a renewable way is to use biomass, however the economic viability of a biorefinery system depends critically on the cost of its supplies. As biomass is not very expensive, logistics is responsible of an important fraction of this cost. Models and methods to optimise biomass supply chains are surveyed in this article, after introducing some technical terms and describing the main activities in these chains. This review aims to give a comprehensive overview of the research in this field with a focus on optimisation modelling issues and solution approaches. Recent advances in the current research and possible new directions are sketched.     

Mechanical Properties of Artificial Stones Produced from Sludge of Stone-Cutting Factories (SSCF): The Effects of Nano-fillers (<Emphasis Type="Italic">a</Emphasis>TiO<Subscript>2</Subscript> and ZnO Nanoparticles)

The aim of this study is to present the advantages of artificial stone production from the sludge of stone cutting factories (SSCFs), which is a self-cleaning and low-cost process, in Lorestan province, Iran. The basic formulation of artificial stone is the sludge stone: 50 % of the weight (wt.%) of sludge stone is cement. 12 wt.%, 25 wt.%, and 7 wt.% of the cement consists of unsaturated polyester resin liquid (UPR), water, and, filler respectively. The filler itself is made up of micro-silica and different amounts of anatase TiO₂-NP and ZnO-NP. Nanoparticles lead to hydrophobicity, the analysis of oil stains, the elimination of bad odor, the sterilization and self-cleaning of artificial stone. The production of artificial stone via this method is pressure-resistant, highly flexible, resistant to freezing and scrapes, lightweight, capable of being cut and formed with a low thickness, and self-cleaning compared to the natural stone.     

A Review on Frying: Procedure,Fat, Deterioration Progress and Health Hazards

For decades, frying has been a popular technique for the preparation of foods, both on domestic and industrial scales. The effects of edible oil type and frying operation conditions on the shelf‐life of fried products, the deterioration progress and the health hazards of fried foods have been studied by various researchers. To achieve a clear conception of the present situation, a collection of the results obtained from previous studies about product deterioration and safety issues due to the frying process, along with related tables, are of prime importance. According to the studies, it can be concluded that a vacuum, oil replenishment, frying temperature, and time of process are the most important parameters affecting the quality of oils and fried products; hence, by controlling them, it is possible to prevent the formation of toxic compounds and loss of nutritional components to a considerable extent during frying operation. Furthermore, according to recent studies indicating significant formation of toxic compounds before the chemical indices of the oil reach the disposal point, more studies are needed to determine whether they are formed at levels that compromise safety and affect consumers’ sensory perception before the established discard points.     

Novel application of PEG/SDS interaction as a wettability modifier of hydrophobic carbonate surfaces

Wettability alteration of carbonate reservoirs from oil-wet to water-wet is an important method to increase the efficiency of oil recovery. Interaction between surfactants and polymers can enhance the effectiveness of surfactants in EOR applications. In this study, the interaction of polyethylene glycol (PEG) with an ionic surfactant, sodium dodecyl sulphate (SDS), is evaluated on an oil-wet carbonate rock surface by using contact angle measurements. The results reveal that wettability alteration of carbonate rocks is achieved through PEG/SDS interaction on the rock surface above a critical aggregation concentration (CAC). The behaviour of PEG/SDS aqueous solutions is evaluated using surface and interfacial tension measurements. Furthermore, the effect of PEG and SDS concentrations and impact of electrolyte addition on PEG/SDS interaction are investigated. It is shown that electrolyte (NaCl) can effectively decrease the CAC values and accordingly initiate the wettability alteration of rocks. Moreover, in a constant SDS concentration, the addition of NaCl leads to a reduction in the contact angle, which can also be obtained by increasing the aging time, temperature and pre-adsorption of PEG on the rock surface.     

Non-darcy free convection inside a wavy enclosure

Buoyancy induced flow and thermal fields characteristics inside a porous wavy walled enclosure have been numerically solved and analyzed. The enclosure consists of two isothermal wavy walls. The two parallel straight walls at the top and the bottom are flat and kept adiabatic. Governing equations are discretized using the Finite Element Method. Simulation was carried out for a range of surface waviness ratios, a = 0–0.5; aspect ratio, A = 2; inverse Darcy number, Da = 0.01–∞; and Rayleigh numbers, Ra = 10°–10⁷ for a fluid having Prandtl number equal to 1.0. Results are presented in the form of streamlines and isothermal lines for different values of surface waviness and porosity.     

Studies on low-temperature salt-hydrate for thermal storage applications

A novel thermal-energy storage concept involving the use of salt-hydrates such as sodium thiosulphate pentahydrate, Na₂S₂O₃·5H₂O is under investigation. With fusion temperatures of many salts lying between 0 and 100°C, such substances may be considered as likely materials to be used in conjunction with solar energy flat-plate collector systems for domestic use. Phase change storage or latent heat storage is concluded to be a promising technique for storing solar energy. The solid-liquid transformation of salt-hydrates is actually a dehydration or hydration of salt, although this process resembles melting or freezing thermodynamically. Three types of behaviour can be identified: congruent, incrongruent, and semicongruent melting. None of the congruent melting salt-hydrates have been judged for use in thermal storage because of cost and safety considerations.