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Hydrogen production from biomass using dark fermentation
No full textHydrogen applicability in the power, chemical and petrochemical industries is constantly growing. Efficient methods of hydrogen generation from renewable sources, including waste products, are currently being developed, even though hydrogen is mainly produced through steam reforming or thermal cracking of natural gas or petroleum fractions. In paper alternative methods of hydrogen production with a particular emphasis on dark fermentation are discussed. The review compiles essential information on strains of bacteria used in the production of hydrogen from waste products in the agroindustry and from lignocellulosic biomass. The effect of such parameters as kind of raw material, method of processing, temperature, pH, substrate concentration, partial pressure of hydrogen, hydraulic retention time, method of inoculum preparation and the type and operating parameters of a reactor on the yield of dark fermentation is discussed. The review aims at presentation of current state of knowledge on the dark fermentation process utilizing waste materials as substrates. The results of investigations with emphasis on the most important issues regarding operating parameters of dark fermentation are also included
Harmonic Forcing of a Two-Segment Timoshenko Beam
No full textThis work treats the lateral harmonic forcing, with spatial dependencies, of a two-segment beam. The segments are compact so Timoshenko theory is employed. Initially the external transverse load is assumed to be spatially constant. The goal is the determination of frequency response functions. A novel approach is used, in which material and geometric discontinuities are modeled by continuously varying functions. Here logistic functions are used so potential problems with slope discontinuities are avoided. The approach results in a single set of ordinary differential equations with variable coefficients, which is solved numerically, for specific parameter values, using MAPLE®. Accuracy of the approach is assessed using analytic and assumed mode Rayleigh-Ritz type solutions. Free-fixed and fixed-fixed boundary conditions are treated and good agreement is found. Finally, a spatially varying load is examined. Analytic solutions may not be readily available for these cases thus the new method is used in the investigation
Has the Euro Promoted Eurozone’s Growth?
No full textThis study aims to assess whether the introduction of the euro promotes systematic growth for the Eurozone. The empirical analysis is based on a natural experiment where the difference-in-differences method is applied to compare Eurozone’s growth rate with that of selected non-Eurozone economies. The major finding of the study is that there are no significant growth effects for the Eurozone emerging from the introduction of the euro
Effect of Electric Field and Temperature on the Behavior of Polypropylene Filled with Nanometric Natural Clay
No full textDuring the last two decades, when compared with pure polymers, nanocomposites have exhibited improved mechanical, thermal, optical and physico-chemical properties, owing to the nanometric particles. Among many other applications polypropylene has found place in electrical systems as a dielectric material. One of these applications is the usage of very thin sheets of polypropylene in high-performance pulse and low-loss RF capacitors as the dielectric medium. Another application is in the power cables as an insulating medium. In an earlier study, the present authors have observed that the breakdown strength improved in polypropylene loaded with nanoclay of various contents. The aim of this study, therefore, is to evaluate the time-to-failure of polypropylene (PP) and polypropylene-based nanocomposite films under the influence of electric field and temperature at the same time because to our best knowledge there is a lack of information in relation to such data
Variation of Current-Density as a Function of Electric-Field Intensity in Synthetic Nanoclay-filled Polypropylene
No full textWithin the scope of this study variation of current-density with electric-field intensity is studied in polypropylene filled with 0% (plain polypropylene), 2%, 4% and 8% synthetic nano-clay by weight. While recording the rms voltage and current, the power-frequency voltage (60Hz) was raised across each specimen at a speed of 226 V/s. In order to see the reproducibility of the results, 5 samples, with the same nano-clay concentration, were subjected tests under the same conditions. Each specimen under test revealed that the current-density varied non-linearly with the electric-field intensity. Moreover, some degree of saturation was observed at relatively higher electric fields in all the specimens. The saturation of the synthetic-clay loaded nanocomposite started at higher electric fields than the plain polypropylene. Up to a critical electric field intensity the capacitance of the materials was found to be almost constant, but for the electric fields higher than the critical electric field, the material behaves non-linearly leading to a dramatic reduction in capacitance
11/14/2018: Faculty Senate Approved Meeting Minutes
No full text11-14-18
1. MS in Data Science - Vote to Approve: 7,0,4 - PASSED
2. Undergraduate Statistics Sequence (MATH 327 and MATH 427) - Vote to Approve: 11,0,0 - PASSE
11/14/2018: Course Change Form CS 541
No full textThe course has been updated to reflect web technology focus on big data and cloud computing. New material will include knowledge about: Python Data Science tolls, Big Data and Hadoop, the R language, the Apache HTTP Server, data mining methods and tools