Electrostatic phase separation: a review

The current understanding and developments in the electrostatic phase separation are reviewed. The literature covers predominantly two immiscible and inter-dispersed liquids following the last review on the topic some 15 years. Electrocoalescence kinetics and governing parameters, such as the applied field, liquid properties, drop shape and flow, are considered. The unfavorable effects, such as chain formation and partial coalescence, are discussed in detail. Moreover, the prospects of microfluidics platforms, non-uniform fields, coalescence on the dielectric surfaces to enhance the electrocoalescence rate are also considered. In addition to the electrocoalescence in water-in-oil emulsions the research in oil-in-oil coalescence is also discussed. Finally the studies in electrocoalescer development and commercial devices are also surveyed. The analysis of the literature reveals that the use of pulsed DC and AC electric fields is preferred over constant DC fields for efficient coalescence; but the selection of the optimum field frequency a priori is still not possible and requires further research. Some recent studies have helped to clarify important aspects of the process such as partial coalescence and drop–drop non-coalescence. On the other hand, some key phenomena such as thin film breakup and chain formation are still unclear. Some designs of inline electrocoalescers have recently been proposed; however with limited success: the inadequate knowledge of the underlying physics still prevents this technology from leaving the realm of empiricism and fully developing in one based on rigorous scientific methodology

Signals in the Soil: An Introduction to Wireless Underground Communications

In this chapter, wireless underground (UG) communications are introduced. A detailed overview of WUC is given. A comprehensive review of research challenges in WUC is presented. The evolution of underground wireless is also discussed. Moreover, different component of UG communications is wireless. The WUC system architecture is explained with a detailed discussion of the anatomy of an underground mote. The examples of UG wireless communication systems are explored. Furthermore, the differences of UG wireless and over-the-air wireless are debated. Different types of wireless underground channel (e.g., In-Soil, Soil-to-Air, and Air-to-Soil) are reported as well

Anisotropy and bedding effects on the hydro geological regime in a confined aquifer to design an appropriate dewatering system

Prediction of groundwater inflow into mining excavations is very important in order to design an effective dewatering system to keep the mine workings dry and create prolonged cone of depression. The effects of anisotropy ratio and bedding on the hydraulic head and drawdown curves of a dewatering test carried out in a fully penetrating well in a confined aquifer have been investigated. An existing numerical finite element model has been used to perform the simulations. The results of the numerical model are compared to those from analytical Jacob and Lohman solution for estimating hydraulic heads and drawdown curves. It was found that the anisotropy ratio and bedding should not have a significant effect on drawdown and the quantity of inflow into a confined aquifer. It was further found that taking the simultaneous effects of anisotropy and bedding into account reduces the differences in the results of analytical and numerical methods. Comparison of the field data and model predictions showed that, the modelling results for a three layer anisotropic aquifer fit well to the field data than those results obtained for a single layer aquifer and the relative error decreased from 4.81 % to 2.98 %

Heavy metal pollution assessment using support vector machine in the Shur River, Sarcheshmeh copper mine, Iran

Mining and related industries are widely considered as having unfavorable effects on environment in terms of magnitude and diversity. As a matter of fact, groundwater and soil pollution are noted to be the worst environmental problems related to the mining industry because of the pyrite oxidation, acid mine drainage generation, release and transport of the heavy metals. Acid mine drainage (AMD) containing heavy metals including Manganese (Mn), Copper (Cu), Lead (Pb), and Iron (Fe), is harmful for the human and aquatic environment. Metal pollution assessment using cost-effective methods, will be a crucial task in designing a remediation strategy. The aim of this paper is to predict the heavy metals included in the AMD using support vector machine (SVM). In addition, the obtained results are compared with those of the general regression neural network (GRNN). Results indicated that the SVM approach is faster and is more precise than the GRNN method in prediction of heavy metals. The results obtained from this paper can be considered as an easy and cost-effective method to monitor groundwater and surface water affected by AMD. © 2012 Springer-Verlag

Procalcitonin Concentration Measured Within the First Days of Cardiac Surgery Is Predictive of Postoperative Infections in Neonates: A Case–Control Study

Increased procalcitonin concentration (PCT) is known to be reliable for the identification of infections even in the presence of the non-specific systemic inflammatory response seen after cardiopulmonary bypass (CPB), whereas increased C-reactive protein concentration (CRP) is not. The present work explored the ability of neonate PCT measured early after cardiac surgery to identify postoperative infections. This was a retrospective case–control study, where PCT was matched between patients with and without infections according to the patient’s age, the CPB length, the use of deep hypothermic circulatory arrest (DHCA), and the postoperative day (POD). The accuracy in the prediction of infections was ascertained and cutoff thresholds were identified. 144 neonates were eligible, and 89 pairs of measurements from 94 patients were analyzed. PCT was a good predictor of infections within POD4, and was a better predictor when compared with CRP at POD1 and POD2. The sum of PCT (pg mL−1) and CRP (mg L−1) > 33 on POD1 or POD2 predicted infections with a 0.68 sensitivity and a 0.82 specificity, and a sum > 49.36 on POD3 or POD4 predicted infections with a 0.82 sensitivity and a 0.93 specificity. In patients with DHCA, PCT was higher than in those without DHCA, and was not predictive of infections. The accuracy of PCT to identify infections after neonatal cardiac surgery is better than that of CRP when measured within 48 h of surgery. The sum of the two markers measured early after surgery is an excellent predictor of postoperative infections.SCOPUS: ar.jDecretOANoAutActifinfo:eu-repo/semantics/publishe

Description of a Male Urogenital Papilla in the California Grunion, Leuresthes tenuis, a Beach-spawning Marine Silverside Fish

Volume: 118Start Page: 102End Page: 10

Forward Osmosis for irrigation Water Supply Using Hybrid Membrane System for Draw Solution Regeneration

Forward Osmosis (FO) process was applied for irrigation water supply using fertilizers and seawater as the draw and feed solutions. Four agents, KNO3, Na2SO4, CaNO3, and MgCl2, plus 35 g/L seawater were used as the draw and feed solutions of the FO process. Net Driving Pressure (NDP) in FO process was manipulated either by increasing the concentration of draw solution (FO process) or by increasing feed pressure (Pressure Assisted FO; PAFO process). Series of NF and RO membranes were used for the regeneration of draw solution. The results showed that PAFO was more energy efficient than FO provided using the low energy of brine flow from the NF/RO membrane for pressurizing the feed solution of PAFO process. Furthermore, the study suggested using a mixture of a primary draw solution, MgCl2, and a secondary draw solution, KNO3, for NO3 supply into the irrigation water. As such, MgCl2 provided the driving force for fresh water extraction while KNO3 is the source of fertilizer for irrigation water. Results showed that water quality provided by MgCl2+KNO3 mixture draw solution was better than that from KNO3 or Ca(NO3)2. The concentrations of NO3 and SO4 in irrigation water were within the recommended level when the diluted draw solution was regenerated by a dual stage low pressure RO process