Recent trends in environmentally friendly water-borne polyurethane coatings: A review

Environmentally friendly waterborne polyurethane (WPU) coatings are used extensively due to their low VOCs emission than solvent based PU coatings. Additionally, WPU coatings have low temperature flexibility, pH stability, water resistance, superior solvent resistance, outstanding weathering resistance and desirable chemical and mechanical properties. This review provides an overview on the recent developments of WPU coatings and their value added applications in the coatings and paint industry. UV-cured WPU coatings provide an important class of green and ecofriendly coatings with outstanding mechanical properties and rapid curing system. Hyper-branched polyurethanes (PUs) show interesting properties, such as high solubility, reactivity and good rheological behavior owing to multiple end groups, compact molecular structure and diminishing chain entanglement. Inherently, WPU coatings have reduced stiffness and mechanical strength that can be increased by the addition of nanoparticles, like Ag, Cu, TiO₂, SiO₂ and many more. Fire retardants, commonly phosphorous, are incorporated in the WPU structure to increase the flame retardancy of WPU coatings.     

Design of distributed layouts

Distributed layouts are layouts where multiple copies of the same department type may exist and may be placed in non-adjoining locations. In this paper, we present a procedure for the design of distributed layouts in settings with multiple periods where product demand and product mix may vary from period to period and where a relayout may be undertaken at the beginning of each period. Our objective is to design layouts for each period that balance relayout costs between periods with material flow efficiency in each period. We present a multi-period model for jointly determining layout and flow allocation and offer exact and heuristic solution procedures. We use our solution procedures to examine the value of distributed layouts for varying assumptions about system parameters and to draw several managerial insights. In particular, we show that distributed layouts are most valuable when demand variability is high or product variety is low. We also show that department duplication (e.g., through the disaggregation of existing functional departments) exhibits strong diminishing returns, with most of the benefits of a fully distributed layout realized with relatively few duplicates of each department type.     

Further observations on enterovirus infection in specific-pathogen-free turkey poults

To evaluate sites of enterovirus replication and to characterize the resulting lesions, twenty 4-day-old specific-pathogen-free (SPF) turkey poults were orally inoculated with an enterovirus. Twenty uninoculated SPF poults served as controls. Inoculated poults were depressed, had ruffled feathers, watery droppings, and pasted vents. Gross lesions were dilated thin-walled ceca with foamy yellow fluid. Immune electron microscopy of the gastrointestinal tract contents revealed an enterovirus with an average diameter of 23.5 nm. Immunoperoxidase and indirect immunofluorescent antibody assays revealed intracytoplasmic staining in enterocytes of the duodenum, jejunum, and ileum. This correlated with the scanning electron microscopy findings, which showed the most lesions in the jejunum and ileum. The ileum had prominent cell outlines because of rounded, distinct, bulging epithelial cells. Histopathology revealed slight shortening of villi and increased crypt depth in the intestines of inoculated poults. Our findings indicate that the small intestine is the site of turkey enterovirus replication, and the gross and microscopic changes observed are determined to result from viral damage to the enterocytes.     

Observer design based on triangular form generated by injective map

A procedure is provided for constructing an injective map as a generalized coordinate change for triangular form transformation. Based on the triangular form a method is developed for designing nonlinear state observers     

Hydrogen absorption and optical properties of Pd/Mg thin films prepared by DC magnetron sputtering

Hydrogen storage in metallic thin films in the form of metal hydride have a great potential to solve the hydrogen storage challenges and also thin films offer an opportunity to grow new samples fast with novel structures. In the present work the ex situ study on structural, optical and hydrogen storage properties of Pd-capped Mg thin films have been investigated. The nano structured Pd-capped Mg thin films have been prepared by DC magnetron sputtering on glass substrate. The as deposited and hydrogenated samples have been characterized by XRD and FESEM. The content of hydrogen in thin films has measured by using Elastic Recoil Detection Analysis (ERDA) technique with 120 MeV₁₀₇ Ag⁺⁹ ions. The temperature dependent hydrogen contents in thin film samples have been estimated and the saturation of hydrogen absorption has been observed at 250 °C among all studied samples. In the optical reflectance spectra, Mg hydride samples have been observed partially transparent in comparison to as deposited Mg film.     

Feature selection techniques in the context of big data: taxonomy and analysis

Applied Intelligence - Recent advancements in Information Technology (IT) have engendered the rapid production of big data, as enormous volumes of data with high dimensional features grow...     

A multiobjective optimization framework for sustainable design of municipal solid waste processing pathways to energy and materials

A large quantity of municipal solid waste (MSW) is generated worldwide, and its effective management is a major problem in urban areas or particularly the areas where waste is dumped. Numerous technological alternatives are available for waste treatment, each with different costs and environmental footprints. For sustainable waste management, both economic and environmental aspects should be considered. Therefore, this study addresses the systematic design of processing routes for the sustainable management and utilization of MSW under economic and environmental criteria. To address this, a generic superstructure-based multiobjective optimization framework is developed. MSW superstructure composes of the potential processing routes for the waste management where MSW can be utilized for energy generation and other valuable waste-based products. On the basis of superstructure, we develop a multiobjective mixed-integer nonlinear programming (MINLP) model that simultaneously maximizes the net profit and minimizes the greenhouse gas (GHG) emissions. The developed optimization model is coded and solved in GAMS to determine the optimal most promising routes for the sustainable processing of MSW. A case of the Emirate of Abu Dhabi is employed to test the applicability of the developed framework. The optimization results emphasize that pathway 2 shows a decent trade-off between economic and environmental objectives, whereas the two most environmentally sustainable processing pathways have the potential to reduce GHG emissions by 58% and 80%, compared with business as usual (BAU) scenario, and also possess potential economic benefits. The insights gained from this analysis guide the municipality planners to devise a promising and sustainable waste management strategy.     

Study on thermal,spectroscopic and electrochemical behavior of some ferrocene-containing organometallic polyesteramides and their siloxane-based block copolymers

The thermal, spectroscopic and electrochemical behavior of some novel ferrocene-containing polyesteramides and their siloxane-based block copolymers are described in the present study. The thermal properties of the organometallic materials were investigated by thermogravimetric analysis (TGA) and compared with their terephthaloyl- and isophthaloyl-based organic analogues. The energies of activation of pyrolysis for the polymeric materials were calculated using Horowitz and Metzger method. The spectroscopic and electrochemical properties of the organometallic polymeric materials were examined by means of UV-visible (UV) and cyclic voltammetric (CV) studies. The interactions of these materials with ds.DNA (extracted from chicken blood) were also investigated.     

Restriction fragment length polymorphism analysis of highly virulent strains of infectious bursal disease viruses from Holland, Turkey, and Taiwan

Ascorbyl free radical (AFR), can be considered as an atoxic and endogenous indicator of oxidative stress. The purpose of our experiments was to investigate the influence of the severity and length of ischemia on the extent of AFR release during myocardial ischemia and reperfusion. For that purpose, isolated perfused rat hearts were submitted to a global ischemia, either total (residual flow 0%) or low flow (residual flow 5%), of 20 or 60 min length. Coronary effluents were collected at different times of experimentation and analyzed with Electron Spin Resonance (ESR) spectroscopy. AFR ESR doublet (g = 2.0054, aH = 0.188 MT) was not detected in coronary effluents collected during control perfusion periods. Nevertheless, during low-flow ischemia, a weak AFR release was noted. Moreover, a sudden and massive AFR liberation was observed at the time of reperfusion: this AFR release was weaker after low-flow ischemia than after total ischemia and was enhanced when the duration of ischemia increased from 20 min to 60 min. The large liberation of AFR noticed during global total ischemia was associated with a greater depression in myocardial contractile function and a lower recovery in coronary flow. In conclusion, our study demonstrates that AFR production at the time of reperfusion depends on the duration and strength of the ischemia, and is related to free radical injury. According to previously described ascorbate/AFR properties, we can conclude that AFR liberation in coronary effluents could represent a marker of oxidative stress during ischemia and/or reperfusion of hearts. This AFR release could be considered a sign of the severity of the ischemic episode, and could be related to the functional impairment during reperfusion.     

The effects of excess phosphoric acid in a Polybenzimidazole-based high temperature proton exchange membrane fuel cell

A series of experiments are conducted in order to investigate the performance of a proton exchange membrane (PEM) fuel cell using a commercially available polybenzimidazole (PBI)-based high temperature membrane. During the study a drastic degradation in performance is observed over time and a significant amount of solid material built-up is found in the flow field plate and the membrane-electrode assembly (MEA). The built-up material is examined by the use of a Scanning Electron Microscope (SEM). Further elemental analysis using Energy Dispersive X-ray Spectroscopy (EDS) finds that the built-up material contains large amount of phosphorus, thus relating it with the excess phosphoric acid found in the MEA. Additional experimental studies show that the built-up material is caused by the excess acid solution in the MEA, and when the excess phosphoric acid is removed from the MEA the fuel cell performance improves significantly and becomes very stable.