Plasticity and drying behavior of terra cotta bodies in the presence of cellulose

The effects of different additions of sodium carboxymethylcellulose (NaCMC) and carboxymethylcellulose (CMC) on viscosity, plasticity and drying behavior of terra cotta bodies were investigated. Relationships between viscosity, plasticity and drying rate, were derived as a function of cellulose concentration. The Bigot curves of drying behavior of terra cotta did not show any curling point for both additions. It was also determined that the plasticity and the drying behavior were found as satisfactory levels according to pure clay at 0.25 wt % additions.     

Luminescence properties of Ammonium Silicon Fluoride films prepared by vapour etching technique

Photoluminescence (PL) properties of Ammonium Silicon Fluoride samples prepared by vapour etching technique are investigated with respect to excitation energy, excitation intensity and temperature. Ageing effect at ambient conditions is also examined by Fourier Transform Infrared Spectroscopy. PL peak maximum blue shifts as the excitation intensity increases and saturates at 2.106 eV. Temperature-dependent variations in PL peak energies and intensities cannot be thoroughly elucidated via Quantum Confinement model alone and require consideration of recombination rates at Si–SiO_x interface. Temperature dependence of integrated PL intensity is treated by a three-component functional form.Infrared absorption bands at 1060 cm^− 1, 1113 cm^− 1 and 1230 cm^− 1 attain saturation with time. Agreement between the saturation time of SiO_x longitudinal optic mode at 1230 cm^− 1 and that deduced from PL measurements in literature is noted. It is shown that PL emissions are intrinsic in nature and have a significant excitonic contribution.     

The Virtual Marathon: Parallel Computing Supports Crowd Simulations

To be realistic, an urban model must include appropriate numbers of pedestrians, vehicles, and other dynamic entities. Using a parallelcomputing architecture, researchers simulated a marathon with more than a million participants. To simulate participant behavior, they used fuzzy logic on a GPU to perform millions of inferences in real time.     

Bin weather data for the provinces of the Eastern Anatolia in Turkey

This paper presents information about bin weather data that have been generated from weather histories and recorded over a period of many years for 14 cities located in the Eastern Anatolia region in Turkey. The analysis covers 14 provinces: A?r?, Ardahan, Bingöl, Bitlis, Elaz??, Erzincan, Erzurum, Hakkari, I?d?r, Kars, Malatya, Mu?, Tunceli, and Van. The bin data for dry-bulb temperature from ?36 °C to 45 °C with 3 °C increments are calculated in six daily 4-h shifts (1–4, 5–8, 9–12, 13–16, 17–20 and 21–24 h). In the calculations, the hourly dry-bulb temperatures recorded by the Turkish State Meteorological Affairs between the years 1990 and 2005 (16 years) are used. Monthly and yearly bin data are presented in tables and on graphs. The information and data presented in this paper hope to fill a gap in information needed by building designers and engineers for simplified energy calculations of buildings in the Eastern Anatolia region.     

Using electrochemical methods to determine alloy 22’s crevice corrosion repassivation potential

Alloy 22 (N06022) is a nickel-based alloy highly resistant to corrosion. In aggressive conditions of high chloride concentration, temperature, and applied potential, alloy 22 may suffer crevice corrosion, a form of localized corrosion. Several electrochemical methods can be used to detect localized corrosion in metallic alloys. One of the most popular for rapid screening is cyclic potentiodynamic polarization (CPP). This work compares the repassivation potentials obtained using CPP to repassivation potentials obtained using the Tsujikawa-Hisamatsu Electrochemical method and the potentiostatic method. For more information, contact Raúl B. Rebak, Lawrence Livermore National Laboratory, 7000 East Ave., L-631, Livermore, CA 94550; (925) 422-1854; fax (925) 422-2105; e-mail rebak1@llnl.gov.     

Conducting Copolymers of 3-Methylthienyl Methacrylate and p-Vinylbenzyloxy Poly(ethyleneoxide) and Their Electrochromic Properties

Summary A random copolymer (CP) containing 3-methylthienyl methacrylate (MTM) and p-vinylbenzyloxy poly(ethyleneoxide) (PEO-VB) units was synthesized. Further graft copolymerization of CP with pyrrole (Py) and thiophene (Th) were achieved in H₂O - sodium dodecyl sulfate (SDS), H₂O - p-toluenesulphonic acid (PTSA) and acetonitrile (AN) - tetrabutylammonium tetrafluoroborate (TBAFB) solvent electrolyte couples via constant potential electrolyses. Characterization was performed by cyclic voltammetry (CV), nuclear magnetic resonance spectroscopy (NMR), and fourier transform infrared spectroscopy (FTIR). The morphologies of the films were examined by scanning electron microscopy (SEM). Conductivities of the samples were measured by using four-probe technique. Moreover, spectroelectrochemical and electrochromic properties of the copolymer obtained from thiophene were investigated by UV-Vis spectrometry and colorimetry.     

Probiotic properties of ice creams produced with dietary fibres from by‐products of the food industry

The objective of this study was to investigate the effects of adding dietary fibre‐rich by‐products to probiotic ice creams. For this purpose, fruit (grape, apricot, apple)‐ and grain (rice, corn, sunflower, barley)‐based by‐products were added to ice cream. The viability of Lactobacillus acidophilus (ATCC 4357D‐5) and Bifidobacterium animalis subsp. lactis (ATCC 27536) was determined with microbial analyses at 1, 15, 30 and 60 days of storage. In conclusion, it was shown that dietary fibre‐rich by‐products could be used in ice cream with improved survival of the probiotic strains without any adverse effects on the physicochemical, microbiological and sensory properties of the ice cream.     

Thermodynamic performance assessment of ocean thermal energy conversion based hydrogen production and liquefaction process

In the proposed study, the thermodynamic performance assessment of ocean thermal energy conversion (OTEC) based hydrogen generation and liquefaction system are evaluated. In this context, the energetic and exergetic analyses of integrated system are conducted for multigeneration. This integrated process is consisted of the heat exchangers, turbine, condenser, pumps, solar collector system, hot storage tank, cold storage tank and proton exchange membrane (PEM) electrolyzer. In addition to that, the impacts of different design indicators and reference ambient parameters on the exergetic performance and exergy destruction rate of OTEC based hydrogen production system are analyzed. The energetic and exergetic efficiencies of integrated system are founded as 43.49% and 36.49%, respectively.     

Investigation of hydrogen addition to methanol-gasoline blends in an SI engine

In this study, effects of hydrogen-addition on the performance and emission characteristics of Methanol-Gasoline blends in a spark ignition (SI) engine were investigated. Experiments were conducted with a four-cylinder and four stroke spark ignition engine. Performance tests were performed via measuring brake thermal efficiency, brake specific fuel consumption, cylinder pressure and exhaust emissions (CO, CO₂, HC, NOx). These performance metrics were analyzed under three engine load conditions (no load, 50% and 100%) with a constant speed of 2000 rpm. Methanol was added to the gasoline up to 15% by volume (5%, 10% and 15%). Besides, hydrogen was added to methanol-gasoline mixtures up to 15% by volume (3%, 6%, 9% and 15%). Results of this study showed that methanol addition increases BSFC by 26% and decreases thermal efficiency by 10.5% compared to the gasoline. By adding hydrogen to the methanol - gasoline mixtures, the BSFC decreased by 4% and the thermal efficiency increased by 2% compared to the gasoline. Hydrogen addition to methanol – gasoline mixtures reduces exhaust emissions by about 16%, 75% and 15% of the mean average values of HC, CO and CO2 emissions, respectively. Lastly, ?t was concluded that hydrogen addition improves combustion process; CO and HC emissions reduce as a result of the leaning effect caused by the methanol addition; and CO2 and NOx emission increases because of the improved combustion.