Blend membranes from poly(2,5-benzimidazole) and poly(styrene sulfonic acid) as proton-conducting polymer electrolytes for fuel cells

Polymer electrolyte membranes were fabricated by blending of poly(2,5-benzimidazole) (ABPBI) and poly(styrene sulfonic acid) (PSSA) at several molar ratios with respect to repeating units. Fourier transform infrared spectroscopy was used to elucidate inter-polymer interactions. Surface morphology was studied through scanning electron microscope. Thermal properties of the membranes were investigated by thermogravimetric analysis and differential scanning calorimetry. The spectroscopic measurements and water uptake (WU) studies indicate a complexation between ABPBI and PSSA where the swelling behavior of membranes increases with the PSSA content. Proton conductivities of the anhydrous and humidified samples were measured using impedance spectroscopy. Proton conductivity of ABPBI:PSSA bend with (1:4) molar ratio was detected as around 10⁻³ S/cm at higher temperatures under anhydrous conditions. On the other hand, the membrane ABPBI:PSSA (1:2) showed the proton conductivity of 0.02 S/cm (ambient temperature, RH = 50%) which is at least five-order of magnitude higher than the anhydrous material.     

Production of diesel-like fuel from waste engine oil by pyrolitic distillation

The aim of this study is to obtain diesel-like fuel from waste lubrication engine oils by pyrolitic distillation method, which can be used in diesel engines. With this aim in mind, waste engine oil is collected in a tank, and it is purified from contaminants such as dust, heavy carbon soot, metal particles, gum-type materials and other impurities by filtering in the process prepared earlier. To investigate effects of additives known as sodium carbonate (NaCO₃), zeolite and lime (CaO) on density, viscosity, flash point, sulfur content, heating value and distillation temperature, the purified oil samples are blended separately with additives having mass basis of 2%, 4%, 6%, 8% and 10%. The mixed samples are exposed to pyrolitic distillation process to produce fuels to be used in engines. Thermal and physical properties of the produced fuels such as density, flash point, viscosity, sulfur content, heating value and distillation temperatures are examined. From these results, the CaO with a ratio of 2% has the highest effect on decreasing of sulfur content of the waste engine oil and on acquiring the most suitable distillation temperatures close to values of a diesel fuel. Diesel-like fuel (DLF) is obtained as 60% of the waste lubrication engine oil.     

Feasibilty study of renewable energy powered seawater desalination technology using natural vacuum technique

With an ever-increasing population and rapid growth of industrialization, there is great demand for fresh water. Desalination has been a key proponent to meet the future challenges due to decreasing availability of fresh water. However, desalination uses significant amount of energy, today mostly from fossil fuels. It is, therefore, reasonable to rely on renewable energy sources such as solar energy, wind energy, ocean thermal energy, waste heat from the industry and other renewable sources. The present study deals with the energy-efficient seawater desalination system utilizing renewable energy sources and natural vacuum technique. A new desalination technology named Natural Vacuum Desalination is proposed. The novel desalination technique achieve remarkable energy efficiency through the evaporation of seawater under vacuum and will be described in sufficient detail to demonstrate that it requires much less electric energy compared to any conventional desalination plant of fresh water production of similar capacity. The discussion will highlight the main operative and maintenance features of the proposed natural vacuum seawater desalination technology which seems to have promising techno-economic potential providing also advantageous coupling with renewable energy sources.     

Production of nanoscale Ba(Zn1/3Nb2/3)O3 microwave dielectric ceramics by polymerised complex method

Ba(Zn_1/3Nb_2/3)O₃ nanoparticles have been synthesized by a polymerised complex method by using precursor materials of barium nitrate, zinc acetate, niobium oxide, hydrofluoric acid and citric acid. Thermal decomposition characteristics and crystallization behavior of the powders were investigated by the thermogravimetric and differential thermal analysis, X-ray diffractometer and Fourier transform infrared spectroscopy. Ba(Zn_1/3Nb_2/3)O₃ phase started to form at low temperature of 400 °C and, single phase Ba(Zn_1/3Nb_2/3)O₃ perovskite structure was obtained at 1000 °C. Microstructural investigation revealed that the major particle size of Ba(Zn_1/3Nb_2/3)O₃ nanoparticles were in the range of 80–110 nm with spherical morphology and homogeneous size distribution. But the powders also contained some agglomeration.     

Protein A carrying monosize PMMA microbeads for the removal of HIgG from human plasma

Protein A-incorporated polymethylmethacrylate (PMMA) microbeads were investigated for specific removal of HIgG from human plasma. The microbeads were prepared by a phase inversion polymerization, and activated by periodate oxidation. Protein A was then incorporated by covalent binding onto these microbeads through hydroxyl groups coming from the stabilizer. The amount of incorporated protein A was controlled by the initial concentrations of protein A in the immobilization medium and pH. The maximum protein A immobilization of 0.615 mg protein A/g PMMA, was observed at a pH of 9.5 corresponding to an initial protein A concentration of 0.1 mg/ml. There was no HIgG adsorption onto the plain PMMA microbeads, while high HIgG adsorptions of up to 32 mg HIgG/g PMMA were achieved with human plasma.     

Flow geometry optimization of channels with baffles using neural networks and second law of thermodynamics

Artificial Neural Networks results from an experimental study on the heat transfer and flow characteristics in channels with baffles are presented. Nine different types of channels with baffles were used in order to test the effects of baffle spacing to and the influence of baffle geometries and their positions on heat transfer, and their flow characteristics. Experiments were performed for laminar and turbulent flows, and Prandtl number of 0.7. The convective heat transfer coefficients and pressure drops provided by the experimental studies and artificially generated data were examined. Finally, the geometric features of the proposed flow geometry to improve heat transfer can be selected in order to yield the maximum opposite reduction in heat exchange channel irreversibility by using entropy generation minimization method. The experimental results for different design constraints show that optimum baffle position angle for laminar flow is 90° and for turbulent flow is 45° and baffle spacing modulo length ratio is 3 for laminar flow and two for turbulent flow, respectively. Then, some new data is generated using artificial neural networks for succession parameters. Also these generated data are compared with experimental results. New flow geometries are presented for the future applications. An erratum to this article is available at .     

Evaluation of heat seal quality of aseptic food containers by ultrasonic and optical microscopic imaging

A rapid and simple method for determination of mono- and diglycerides in milk and milk products is described. The emulsifiers were extracted from the samples with organic solvents. Soxhlet extraction and supercritical fluid extraction were compared. To avoid interference of the co-extracted triglycerides with mono- and diglycerides during the GC run, triglycerides were separated by solid phase extraction. Then the emulsifiers were silylated and determined by GC-FID. Optimising GC parameters, the contents of mono- and diglycerides could be determined in the same run within 20 min. Mono- and diglycerides were gathered in two separate groups and quantified with betulin as internal standard. Commercial samples were analysed for the presence of mono- and diglycerides. The recovery rates of monoglycerides were about 98% for skim milk and 99% for dessert. Spiked diglycerides were found with 101% in skim milk and 94% in dessert. The limit of determination was 0.001% for mono- and 0.006% for diglycerides.     

Enhancing phosphate removal from wastewater by using polyelectrolytes and clay injection

Aluminum sulfate, alum, is a common chemical coagulant used for coagulation. Recently, polymers have been utilized in coagulation/flocculation processes for water purification. In this study, the ability of two organic polymers, tannin (natural polyelectrolyte) and AN913 (synthetic anionic polyelectrolyte), and clay to act as coagulant aids was tested, in the removal of phosphate from synthetic wastewater. Contaminants in synthetic waters were coagulated using alum, alum+clay, alum+tannin, alum+AN913, alum+tannin+clay and alum+AN913+clay. Alum together with polymers as coagulant aids yielded a significant improvement in phosphate removal compared with alum alone, for initial phosphate concentrations of 5–15 mg/l PO₄³⁻. The use of clay and polyelectrolytes improved the efficiency of phosphate removal and lowered the required alum dose. Fourier transform infrared (FTIR) spectroscopy was used for the identification and characterization of the aluminum species formed during dephosphorization of the synthetic wastewater with and without tannin, AN913 and clay. Evidence from FTIR spectroscopy showed the formation of aluminum hydroxyphosphate, hydroxy-Al-tannate and aluminum complexes containing phosphorus, tannin and AN913.     

p53 expression in ovarian carcinoma with regard to second-look findings

The coefficient of relationship by isonymy is Ri=sigma(n(n-1)/2(N(N-1)) in which n is the number of persons of each surname and N=sigma n. Dividing Ri into two components, one for the contribution of co-residence (family size) and the other for diversity of surnames among residences is achieved by letting a1 represent sigma n(n-1) for all residents, a2 represent sigma n(n-1) after eliminating all but one individual of any name at any residence, and b1 represent 2N(N-1) for all residents. Then the component for inter-residence diversity is a2/b1 and the component for relationship by co-residence (including the interaction) is (a1-a2)/b1. By the same logic it is possible to calculate separately the interaction component, but the additional information seems of limited importance.