Oxidative solution polymerization of aniline hydrochloride onto electrospun nanofibers mats of polylactic acid: Preparation method and characterization

In this work, we present the preparation of polylactic acid (PLLA)/polyaniline (PANI) conductive composite nanofibers mats. They are prepared by bulk oxidative solution polymerization of PANI onto electrospun non‐woven fibers mats of PLLA. The PANI ratio in the composite is about 70%w/w. Scanning electron microscopy (SEM) shows that PLLA nanofibers are randomly oriented, beads free with diameters of 186 ± 85 nm, The PLLA/PANI composite nanofibers diameter values are 518 ± 128 nm with a good adherence between PANI and PLLA nanofibers. DSC and XRD measurements reveal an amorphous structure of the electrospun PLLA fibers due to the rapid evaporization of the solvent. FTIR and UV–vis spectra reflect good mutual interactions between PANI and PLLA chains. The DC‐conductivities ( ) far better than other published ones for similar composites prepared by bulk oxidative solution polymerization of PANI onto other electrospun nanofiber mats or with electrospun nanofibers from a solution mixture of PLLA and PANI. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015 , 132, 41618.     

Effects of coating layer and release medium on release profile from coated capsules with Eudragit FS 30D: an in vitro and in vivo study

The aim of the present research was to evaluate the impact of coating layers on release profile from enteric coated dosage forms. Capsules were coated with Eudragit FS 30D using dipping method. The drug profile was evaluated in both phosphate buffer and Hank’s solutions. Utilization X-ray imaging, gastrointestinal transmission of enteric coated capsules was traced in rats. According to the results, no release of the drug was found at pH 1.2, and the extent of release drug in pH 6.8 medium was decreased by adding the coating layers. The results indicated single-layer coated capsules in phosphate buffer were significantly higher than that in Hank’s solution. However, no significant difference was observed from capsules with three coating layers in two different dissolution media. X-ray imaging showed that enteric coated capsules were intact in the stomach and in the small intestine, while disintegrated in the colon.     

The importance of accurate lesion placement in posteroventral pallidotomy. Report of two cases

OBJECTIVES: The effects of anemia of prematurity during bronchopulmonary dysplasia (BPD) as well as on the metabolic and erythropoietic functions were determined before and after a transfusion. Fourteen anemic (Hb range: 65-88 gm/L), oxygen dependent (fraction of inspired oxygen < or = 35%), nonventilated, preterm infants with BPD were studied at a postnatal age of 6 +/- 2 weeks. STUDY DESIGN: Cardiac output, heart rate, mean velocity of circumferential fiber shortening, shortening fraction (SF), and stroke volume were assessed by pulsed and continuous wave Doppler echocardiography. Values for resting oxygen consumption, carbon dioxide production, and energy expenditure were obtained by indirect calorimetry. The affinity of oxygenated hemoglobin was determined by a blood oxygen dissociation analyzer. RESULTS: An increased hemoglobin level resulted in a suppression of erythropoietin secretion (p < 0.001), whereas heart rate, cardiac output, stroke volume, and SF decreased (p < 0.05). Weight gain before and after transfusion were similar. Plasma lactate levels decreased from 1.6 +/- 0.3 to 1.2 +/- 0.3. Oxygen consumption, carbon dioxide production, and energy expenditure were not affected. CONCLUSIONS: Anemia of prematurity and BPD increase heart rate, cardiac output, stroke volume, and SF. These hemodynamic compensatory responses are normalized by transfusion.     

Empirical equations for electrical conductivity and density of Zn,Cd and Mn sulphate solutions in the range of electrowinning and electrorefining electrolytes

Electrical conductivities and densities of acidic zinc, cadmium and manganese sulphate solutions were measured. Empirical equations have been derived to represent the measured values with high accuracy. Electrical conductivity of solutions has been shown to be expressed as a logarithmic function of temperature, a second order polynomial function of sulphuric acid concentration and a linear function of metal ion concentration. It can be deduced that the density of solution can be described as a linear function of metal ion concentration, temperature and sulphuric acid concentration. These equations could be used to improve the electrowinning or electrorefining process conditions.     

Hybrid PV/fuel cell system design and simulation

In this paper, a hybrid Photovoltaic (PV)-fuel cell generation system employing an electrolyzer for hydrogen generation is designed and simulated. The system is applicable for remote areas or isolated loads. Fuzzy regression model (FRM) is applied for maximum power point tracking to extract maximum available solar power from PV arrays under variable insolation conditions. The system incorporates a controller designed to achieve permanent power supply to the load via the PV array or the fuel cell, or both according to the power available from the sun. Also, to prevent corrosion of the electrolyzer electrodes after sunset, i.e. when its current drops to zero, the electric storage device is designed so as to isolate the electrolyte from the electrolysis cell.     

A Magnetic Particle‐Supported Sulfonic Acid Catalyst: Tuning Catalytic Activity between Homogeneous and Heterogeneous Catalysis

Surface functionalization of magnetic particles is an elegant way to bridge the gap between heterogeneous and homogeneous catalysis. The introduction of magnetic particles (MPs) in a variety of solid matrices allows the combination of well‐known procedures for catalyst heterogenization with techniques for magnetic separation. We have conveniently loaded sulfonic acid groups on magnetic particles supports in which chlorosulfonic acid is used as sulfonating agent. The main targets are room temperature, solvent‐free conditions, rapid (immediately) and easy immobilization technique, and low cost precursors for the preparation of highly active and stable MPs with high densities of functional groups. The inorganic, magnetic, solid acid catalyst was characterized via Fourier transform infrared spectroscopy (FT‐IR), X‐ray diffraction (XRD), thermal gravimetric analysis (TGA), X‐ray photoelectron spectroscopy (XPS), transmission electron microscopy (TEM), dynamic light scattering (DLS), vibrating sample magnetometer (VSM) and titration. The catalyst is active for the Hantzsch reaction and the products are isolated in high to excellent yields (90–98%). Supporting this acid catalyst on magnetic particles offers a simple and non‐energy‐intensive method for recovery and reuse of the catalyst by applying an external magnet. Isolated catalysts were reused for new rounds of reactions without significant loss of their catalytic activity.     

Industry–academia collaborations in software testing: experience and success stories from Canada and Turkey

Collaboration between industry and academia supports improvement and innovation in industry and helps to ensure industrial relevance in academic research. However, many researchers and practitioners believe that the level of joint industry–academia collaborations (IAC) in software engineering (SE) is still relatively very low, compared to the amount of activity in each of the two communities. The goal of the empirical study reported in this paper is to characterize a set of collaborative industry–academia R&D projects in the area of software testing conducted by the authors (based in Canada and Turkey) with respect to a set of challenges, patterns and anti-patterns identified by a recent Systematic Literature Review study, with the aim of contributing to the body of evidence in the area of IAC, for the benefit of SE researchers and practitioners in conducting successful IAC projects in software testing and in software engineering in general. To address the above goal, a pool of ten IAC projects (six completed, two failed and two ongoing) all in the area of software testing, which the authors have led or have had active roles in, were selected as objects of study and were analyzed (both quantitatively and qualitatively) with respect to the set of selected challenges, patterns and anti-patterns. As outputs, the study presents a set of empirical findings and evidence-based recommendations, e.g.: it has been observed that even if an IAC project may seem perfect from many aspects, one single major challenge (e.g., disagreement in confidentiality agreements) can lead to its failure. Thus, we recommend that both parties (academics and practitioners) consider all the challenges early on and proactively work together to eliminate the risk of challenges in IAC projects. We furthermore report correlation and interrelationship of challenges, patterns and anti-patterns with project success measures. This study hopes to encourage and benefit other SE researchers and practitioners in conducting successful IAC projects in software testing and in software engineering in general in the future.