Application of Artificial Neural Network and Fuzzy Inference System in Prediction of Breaking Wave Characteristics

Abstract Wave height as well as water depth at the breaking point are two basic parameters which are necessary for studying coastal processes. In this study, the application of soft computing-based methods such as artificial neural network (ANN), fuzzy inference system (FIS), adaptive neuro fuzzy inference system (ANFIS) and semi-empirical models for prediction of these parameters are investigated. The data sets used in this study are published laboratory and field data obtained from wave breaking on plane and barred, impermeable slopes collected from 24 sources. The comparison of results reveals that, the ANN model is more accurate in predicting both breaking wave height and water depth at the breaking point compared to the other methods

Study of effective parameters on generating submicron (nano)-bubbles using the hydrodynamic cavitation

Although submicron (nano)-bubbles (NBs) have been broadly used in the laboratory flotation processes, the role of critical factors in their generation is not adequately explored in the literature. The present study investigates the effect of six key factors on generating submicron-sized bubbles and its application to coarse-sized quartz flotation. Interaction of influential factors is highlighted, which was generally overlooked in previous studies. These parameters i.e. frother type (MIBC and A65), frother dosage (50-130 mg/L), air flow rate (0.1-0.4 L/min), pressure in Venturi tube (250-400 kPa), liquid temperature (22-42 °C) and pH (6-10) were evaluated through software based statistical fractional factorial design. The size distribution of NBs produced by the principle of hydrodynamic cavitation was measured using a laser particle size analyzer (LPSA), and Sauter mean bubble diameter (d32) was considered as the response of experimental design. Batch flotation experiments were performed with and without the A65 and MIBC-NBs. The results of experimental design showed that relative intensity of the main factors followed the order of air flow rate>temperature>frother type as the most effective parameters on the bubble size. It was revealed that the lowest air flow rate (0.1 L/min) produced the smallest bubbles. Meanwhile, the d32 decreased as the liquid temperature increased, and the bubble size strongly was related to the frother type and its concentration. Indeed, with changing frother from MIBC to A65, the reduction in mean bubble size was two-fold. Interaction of frother type with its dosage, air flow rate and pressure were statistically recognized significant on the mean bubble size, which was confirmed by p-values. Finally, flotation recovery of quartz particles improved ca. 22% in the presence of NBs compared to the conventional flotation

Biological synthesis of nanosized sulfide semiconductors: current status and future prospects

There have been extensive and comprehensive reviews in the field of metal sulfide precipitation in the context of environmental remediation. However, these works have focused mainly on the removal of metals from aqueous solutions-usually, metal-contaminated effluents-with less emphasis on the precipitation process and on the end-products, frequently centering on metal removal efficiencies. Recently, there has been an increasing interest not only in the possible beneficial effects of these bioremediation strategies for metal-rich effluents but also on the formed precipitates. These metal sulfide materials are of special relevance in industry, due to their optical, electronic, and mechanical properties. Hence, identifying new routes for synthesizing these materials, as well as developing methodologies allowing for the control of the shape and size of particulates, is of environmental, economic, and practical importance. Multiple studies have shown proof-of-concept for the biological synthesis of inorganic metallic sulfide nanoparticles (NPs), resorting to varied organisms or cell components, though this information has scarcely been structured and compiled in a systematic manner. In this review, we overview the biological synthesis methodologies of nanosized metal sulfides and the advantages of these strategies when compared to more conventional chemical routes. Furthermore, we highlight the possibility of the use of numerous organisms for the synthesis of different metal sulfide NPs, with emphasis on sulfate-reducing bacteria (SRB). Finally, we put in perspective the potential of these methodologies in the emerging research areas of biohydrometallurgy and nanobiotechnology for the uptake of metals in the form of metal sulfide nanoparticles. A more complete understanding of the principles underlying the (bio)chemistry of formation of solids in these conditions may lead to the large-scale production of such metal sulfides, while simultaneously allowing an enhanced control over the size and shape of these biogenic nanomaterials