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A New Test of Filterability for Unprocessed Wines Evaluation of the Enzyme Efficiency
Get PDFA new Test of Filterability has been developed. Measurements carried out with different types of wines indicate that the new filterability index is a useful tool for understanding and predicting the propensity to fouling of treated or untreated wines, e.g. with or without enzyme addition. The measurement method used in the Test of Filterability, requires only one type of membrane for all types of wine, and uses the same equipment as the traditional Fouling Index. Numerous trials have demonstrated that the filtration of wines is governed by standard blocking law. The definition of the new Test of Filterability, based on this filtration law, is proposed. The choice of membrane and the selection of the optimal pore size were based on the results of the experiments. Current methods used for the determination of fouling properties in wine filtration have been developed for the membrane filtration of small quantities of suspended matter. Enzyme treatment is a process often used in wine clarification. The new Test of Filterability indicates the best conditions for the filtration of all types of wines. The test is easy to implement and has been validated with various wines. This new Test of Filterability is an important tool for winemakers as it constitutes a simplified test of a wine's filterability. The new test may also be used to determine the filtration process that is best adapted to each wine while reducing the number of operations. The same approach may be adopted for the filtration of other liquids. 
Binary Beetle Antennae Search Algorithm for Tangency Portfolio Diversification
Get PDFThe tangency portfolio, also known as the market portfolio, is the most efficient portfolio and arises from the intercept point of the Capital Market Line (CML) and the efficient frontier. In this paper, a binary optimal tangency portfolio under cardinality constraint (BOTPCC) problem is defined and studied as a nonlinear programming (NLP) problem. Because such NLP problems are widely approached by heuristic, a binary beetle antennae search algorithm is employed to provide a solution to the BTPSCC problem. Our method proved to be a magnificent substitute to other evolutionary algorithms in real-world datasets, based on numerical applications and computer simulations
Electrokinetic Desalination of Compound Building Materials by Applying Electric Field
Get PDFDamaging of building materials is directly connected to the salt crystallization. The present research is based on removal of NaCl from compound building materials, where a direct current (DC) electric field was applied to the mortar plus bricks system. The main objective of this work is to investigate the electrokinetic desalination methodology that can provide sufficient removal of salts. pH neutralization in the surrounding of mortar plus bricks system is crucial to obtain sufficient desalination. For this purpose, the electrodes across the brick were inserted in kaolin clay mixed with buffer agents to suppress the pH changes. Most of the experiments were performed with kaolin clay and sponge. The concentration of chloride ions and sodium ions in all the segments and clay poultice was measured using argentometric titration method and flame photometer, whereas the pH variations in the entire system was measured by using pH indicator papers. The electrokinetic desalination was found to be an efficient method as 86 % removal of chloride and 80 % removal of sodium was achieved
Synthesis of Antibacterial Coating Using Chitosan, Polyethylene Glycol and Silver Nanoparticles and Investigation of Their Antibacterial Properties
Get PDFChitosan/ Polyethylene glycol and silver nanoparticles based antibacterial coating has been synthesized and applied to cotton cloth using sonochemical technique. In addition to the synthesis of nanoparticles using Pyrus seed extract (Green synthesis), Chitosan and PEG compound has also been used to develop the coating in this research. The coating obtained with this compound possesses good antibacterial properties and results. The study shows that the coated fabrics and silver nanoparticles show highly potent antibacterial activity towards gram negative and gram-positive bacteria. A comparison of coating with single and multiple components is studied; specifically, a comparison of pure chitosan and polyethylene glycol coating with their blend is studied. Agar plate test is performed against pseudomonas aeruginosa, Acinetobacter baumannii and methicillin-resistant staphylococcus aureus (MRSA), and the proposed process is helpful in healthcare industry and specified applications
Electrochemical Reduction of CO2: Influence of Pre-treating the Carbon Support
Get PDFThe production of useful chemicals by electroreducing CO2 it is a promising approach to reduce the levels of this greenhouse gas in the atmosphere. This is not a straightforward process due to the high stability of the CO2 molecule and low selectivity however, these barriers can be overcome by using an appropriate catalyst. This research focus on the effect of pre-treating the carbon supports before incorporating the catalyst on the electroreduction of CO2. We found that the electrochemical behaviour of the carbon supports is modified by the nature of the pre-treatment used. From the structure perspective, the results showed partial destruction of the carbon structure mainly after the oxidative treatments nevertheless, the introduction of defect sites in the carbon structure contributed to catalyst performance. This improvement was proved by the LSV data that showed the reduction of the current associated with the hydrogen reduction reaction
Nurturing Plasmonic Properties of Nanocomposite Thin Films: The Importance of Optimum Oblate Shape
Get PDFMetal nanoparticles (MNPs) embedded dielectric thin films are very crucial for many optoelectronic applications. This report investigates various ways of tuning the plasmonic properties of such nanocomposite thin films. For this, the well-known plasmon resonance condition was first generalized to include the shape and volume fraction of MNPs. This was followed by deriving an empirical formula for the resonance position (λR) which was worked out to be the positive root of a quadratic equation. The coefficients of the deduced quadratic relation involve the parameters obtained from the empirical fit to some of the experimental dielectric functions of MNPs available in literature. The derived working formula enables research community to tune the LSPR of nanocomposites in the whole range of visible wavelengths. The derived formula also concluded that with known lower volume fractions, shape of MNPs affects λR the most, compared to the other parameters. The derived formula was validated by calculating the full extinction spectra. It was shown for the first time that there exists an optimum value of oblate shape to give maximum resonance for a given nanocomposite
Design of Piezoelectric Tile for Energy Harvesting: Experimental Approach
Get PDFThe generation of electricity by renewable energies is an important need of today's society. Piezoelectric energy harvesting is one of these useful technologies which can generate electricity by applying external force on piezoelectric material. This study illustrates more power generation from piezoelectric tile by changing the situation of piezo discs and connect to proportional electrical circuit. Two different designs of piezoelectric tile are presented by performing experimental analyses. The experimental results showed that placing piezoelectric elements in a bending position leads to higher power generation in comparison with traditional flat positioning, which was approximately 78 times far superior. It is also revealed that by design of an electrical circuit, the tile can be advantageous for lighting in crowded sidewalks with required lighting time. The results of this paper can be beneficial in the design and fabrication of these tiles for different applications
Development of Sugar Free and Fortified Chocolates with D-Optimal Design Approach
Get PDFThe increasing numbers of overweight or chronically obese individuals have led the market to produce sweet snacks and desserts that are low in calories, low in fat or low in sugar. Sugar replacers have low calorific value and lower glycaemic index as compared to sucrose which not only helps in controlling weight but also is safe for diabetics. The study is aimed to develop a sugar free chocolate by using a combination of various zero calorie sweeteners i.e., stevia, isomalt and erythritol through response surface methodology (RSM). The final run optimized by RSM consists of 21.9g cocoa butter, 5.1g erythritol, 0.10g stevia and 14.9g isomalt. Organoleptic evaluation of modified chocolates was evaluated using 9 point hedonic scale for the parameters like, appearance, color, aroma, taste, texture, mouthfeel, aftertaste and overall acceptability. The overall acceptability of sugar free chocolates was found to be 8.9. Further, the fortification of chocolates was done with the help of vitamins and minerals rich fruit powders such as beetroot powder, jamun seed powder and pink pithaya powder (dragon fruit). Vitamins and minerals analysis was performed for sugar free chocolate fortified with beetroot. Shelf-life study of sugar free chocolate fortified with beetroot was carried out
Effect of Meteorological Conditions and Anthropogenic Factors on Air Concentrations of PM2.5 and PM10 Particulates on the Examples of the City of Kielce, Poland
Get PDFThe paper analyzes the influence of meteorological conditions (air temperature, wind speed, humidity, visibility) and anthropogenic factors (population in cities and in rural areas, road length, number of vehicles, emission of dusts and gases, coal consumption in industrial plants, number of air purification devices installed in industrial plants) on the concentration of PM2.5 and PM10 dusts in the air in the region of Kielce city in Poland. Spearman correlation coefficient was used to evaluate the relationship between the mentioned independent variables and air quality indicators. The calculated values of the correlation coefficient showed statistically significant relationships between air quality and the amount of installed air purification equipment in industrial plants. A statistically significant effect of the population in rural settlement units on the increase in air concentrations of PM2.5 and PM10 was also found, which proves the influence of the so-called low emission of pollutants on the air quality in the studied region. The analyses also revealed a statistically significant effect of road length on the decrease in PM2.5 and PM10 air content. This result indicates that a decrease in traffic intensity on particular road sections leads to an improvement in air quality. The analyses showed that despite the progressing anthropopression in the Kielce city region the air quality with respect to PM2.5 and PM10 content is improving. To verify the results obtained from statistical calculations, parametric models were also determined to predict PM2.5 and PM10 concentrations in the air, using the methods of Random Forests (RF), Boosted Trees (BT) and Support Vector Machines (SVM) for comparison purposes. The modelling results confirmed the conclusions that had been made based on previous statistical calculations
Suitable Na2O-SiO2, BaO-SiO2 Based Coatings for Stainless Steels
Get PDFTwo frites with 40 wt.%SiO2-20 wt.%B2O3-17 wt.%Na2O (G1) and 42wt.%SiO2-24wt.%BaO-18 wt.%CoO (G2) compositions were prepared and applied on stainless steel by the slurry method. The samples were heated at 950ºC (G2) and 860ºC (G1). The XRD results revealed the sodium silicate and barium silicate phases as well as almost 770 HV, 543 HV microhardness in G1 and G2 coats respectively. The thermal expansion coefficients were α=10.9×10-6/K(G1) and α=13.31×10-6/K (G2) respectively. According to EDS results the alkaline earth ions (and CoO) migration into the glass- steel interface was occurred in both coats. The dry sliding friction and wear behavior were investigated using a 4mm diameter AISI52100 steel pin on disk geometry under 5,10 and 18 N loads. The average wear rate were w.r: 32 ×10-14(m3/N.m) and w.r:5×10-14(m3/N.m) in G1 and G2 coats. Then two frites were mixed and heat treated at 800ºC with high heating and cooling rate. The resulted composite (G1-G2) shows almost the average wear rate 4×10-14(m3/N.m), while the coefficient friction of G1-G2 composite was not improved significantly