Design and Implementation of Fuel Cell and Photovoltaic Panel-Supported Ozonation System

It is normal for a produced agricultural product or food to be transported to distances far from where it is produced. However, it is important to keep the product fresh in this transportation. There are many methods used to extend the life of the food during transport. The chemical method is the most used. However, the chemical method is harmful to human health. One of the methods used for storing, preserving and transporting agricultural products is ozonation and air conditioning. In this study, a system was designed to extend the life of the product in the storage and transport of food products. With the developed system, temperature, relative humidity and ozone were produced and their amounts were controlled according to the type of product being carried. In the design, polymer exchange membrane fuel cell was used for the required oxygen. The energy requirement of the system was provided by a photovoltaic panel to get rid of the generator dependency on supplied electrical power. The applicability of the system to refrigerated vehicles, especially those used in food transportation, was examined.     

Statistical Reliability of Phase Fraction Determination Based on Electron Backscatter Diffraction (EBSD) Investigations on the Example of an Al-TRIP Steel

The aim of this article is to discuss the representativeness of electron backscatter diffraction (EBSD) mapping data for phase fraction determination in multiphase materials. Particular attention is paid to the effect of step size and scanned area. The experimental investigations were carried out on a low-alloyed steel with transformation induced plasticity (TRIP) that shows a relatively heterogeneous distribution of residual austenite in a ferrite matrix. EBSD scans of various area sizes and step sizes were carried out and analyzed with respect to the determined austenite phase fraction. The step size has only an indirect influence on the results, as it determines the size of the investigated area if the number of measurement points is kept constant. Based on the experimental results, the optimum sampling conditions in terms of analyzed area size and the number of measurement points were determined. These values were compared with values obtained from Cochran’s formula, which allows calculation of sampling sizes for predefined levels of precision and confidence. A significant deviation of experimental from theoretical optimum sample sizes was found. This deviation is, for the most part, a result of the heterogeneous distribution of the austenite phase. Depending on grain size and volume fraction of the second phase, the false assignment of phases at grain boundaries also may introduce a significant error. A general formula is introduced that allows estimation of the error caused by these parameters. Finally, a new measurement scheme is proposed that allows improvement of reliability and representativeness of EBSD-based phase determination without large sacrifices in measurement time or data set sizes.     

Comparison of influence of different manufacturing methods on the cleaning efficiency of rotary nickel–titanium files

The purpose of this study was to evaluate and compare cleaning effectiveness of TwistedFile, GT series X, Revo‐S, RaCe, Mtwo, and ProTaper Universal rotary files in curved canals. Seventy mesiobuccal canals of extracted human first maxillary molars were divided into seven groups of 10 samples each. Canals were prepared with six nickel–titanium (NiTi) rotary systems and manual K‐Flexofile. Irrigation was performed with 2 mL 2.5% NaOCl solution after each file, and 5 mL 2.5% NaOCl was used for the final flush. After the roots were split longitudinally, the presence of debris and smear layer was visualized using scanning electron microscopic photomicrographs taken at coronal, middle, and apical third. Mean scores for debris and the smear layer were calculated and statistically analyzed for significance between groups using the Kruskal–Wallis nonparametric analysis of variance (P < 0.05) and Mann–Whitney U test (P < 0.001). There was no significant difference among the groups in terms of debris and smear layer scores (P > 0.05). Without considering the preparation method used, while no statistically significant difference was found between the coronal third and the middle third (P > 0.05), higher amount of debris and smear layer were found in apical third (P = 0.001). The new generation of NiTi rotary files including the Twisted File and GT Series X presented similar cleaning effectiveness compared with traditionally ground NiTi rotary files. Microsc. Res. Tech. 76:231–236, 2013. © 2012 Wiley Periodicals, Inc.     

Association of anxiety,sleepiness, and sexual dysfunction with restless legs syndrome in hemodialysis patients

Restless legs syndrome (RLS) is characterized by unpleasant sensations, pain in the legs along with irresistible urges to move the legs when at rest. It is often accompanied by sleep disturbance. The purpose of this study was to assess the association of anxiety and sleepiness with sexual function in hemodialysis patients with and without RLS. Sociodemographic parameters, laboratory data of hemodialysis patients from three dialysis centers were collected prospectively. Anxiety, sleepiness, sexual function, and presence of RLS symptoms were assessed with standardized questionnaires as the RLS Diagnosis and Scale, Hamilton Anxiety Rating Scale, Epworth Sleepiness Scale (ESS), Arizona Sex Experiences Scale (ASEX). Univariate, regression tree method were used for statistical analysis. RLS was observed in 45.9% (n = 113) of hemodialysis patients (n = 246). The mean age of patients and duration of hemodialysis were 59.7 ± 14.0 and 4.9 ± 4.2 years, respectively. The correlation between Arizona Sexual Experiences Scale (ASEX) and sociodemographic features was significant (P < 0.0001). Patients with RLS had higher scores for anxiety (9.4 ± 7.8 with RLS and 6.8 ± 6.0 without), higher ESS (ESS, 6.6 ± 5.2 with RLS and 4.6 ± 4.0 without), and higher ASEX (24.6 ± 5.7 with RLS and 22.5 ± 6.8 without) than did those without RLS. The presence of RLS symptoms in hemodialysis patients was associated with sleepiness, anxiety, and sexual dysfunction. A regression tree method, which is a different statistical method, can help physicians estimate patients ASEX, RLS, ESS, and anxiety scores.     

A novel Cu(II) Complex of Picolinate and 1,10-Phenanthroline: Preparation,Crystal Structure Determination,Spectroscopic Characterization and Nonlinear Optical Studies

A newly synthesized copper (II) complex of picolinic acid (also known as 2-pyridinecarboxylic acid) and 1,10-phenanthroline, [Cu(pic)₂(phen)]·H₂O, has been prepared, and its crystal structure has been fully characterized by means of X-Ray diffraction method. The spectroscopic and electronic properties have been also investigated by the applying of FT-IR, Raman and UV–Vis spectroscopies. Density functional theory (DFT) calculations have been performed by using hybrid B3LYP level in order to provide a deep understanding on the relation of the structural, spectroscopic and electronic properties with nonlinear optical properties. The intensive interactions between the bonding orbitals of donor O/N atoms and antibonding orbitals of Cu(II) lone pairs confirm crystal structure characterized with distorted octahedron. Each of the parameters such as small energy gap between HOMO and LUMO, high second order perturbation energies, elongation of the conjugated π system and d⁹ electron configuration of Cu(II) ion induce the first static hyperpolarizability (β) parameter of [Cu(pic)₂(phen)]·H₂O.     

Robust optimization of SegNet hyperparameters for skin lesion segmentation

Multimedia Tools and Applications - Melanoma is considered the deadliest form of skin cancer, and the number of cases is increasing day by day. The early diagnosis of melanoma is critical, as it...     

Predicting flow conditions over stepped chutes based on ANFIS

Chute flow may be either smooth or stepped. The flow conditions in stepped chutes have been classified into nappe, transition and skimming flows. In this paper, characteristics of flow conditions are presented systematically under a wide range of critical flow depth, step height and chute slope. The Adaptive Network Based Fuzzy Inference System (ANFIS) is used to predict flow conditions in stepped chutes using critical flow depth, step height and chute slope information. The proposed model performance is determined by threefold cross validation method. The evaluated classification accuracy of ANFIS model is 99.01%. The test results showed that the proposed ANFIS model can be used successfully for complex process control in hydraulic systems.     

Monitoring the Microstructural Evolution in Spheroidized Steels by Magnetic Barkhausen Noise Measurements

The aim of this study is to monitor nondestructively the degree of spheroidization in steels by Magnetic Barkhausen Noise (MBN) method. Various series of specimens consisting of either lamellar pearlite or partially/completely spheroidized carbides were produced from AISI 1060 steel by appropriate heat treatments. All specimens were characterized by metallographic examinations, hardness and MBN measurements. The results show that MBN signals are very sensitive to the variations in the microstructure caused by the spheroidizing heat treatment. The change of microstructure, from coarse lamellar carbides to uniformly dispersed spherical carbides in ferrite matrix, is reflected as higher Barkhausen activity due to less effective pinning of domain walls.     

Sulfur removal from original and acid treated lignites by pyrolysis

Six original, three hydrochloric acid treated and three demineralized lignite samples were pyrolysed at seven different temperatures between 350 and 950 °C for 7 min under evolved gas atmosphere. All samples and their chars were analysed quantitatively for their total sulfur content and pyritic, sulfate and organic sulfur forms. The alkaline oxide contents of original lignites and their hydrochloric acid treated counterparts were determined. The results clearly indicate that calcium and sulfurous compounds in the parent lignites undergo various chemical changes during pyrolysis. The pyrolysis temperature, types of sulfur and calcium compounds, all affect the behaviour of sulfur during pyrolysis. Higher pyrolysis temperatures favour total sulfur removal for all lignites, reaching 30-54% around 850 and 950 °C. HCl treatment and demineralization decreases calcium contents, hence, increases quantitative sulfur removal from the lignites by pyrolysis. The maximum total sulfur removal from acid treated lignites is observed as 77%. The ratios of the total sulfur to heating value decreases with increases of pyrolysis temperature up to around 600 °C for acid treated lignites and no major changes are observed at higher pyrolysis temperatures; no common behaviour is observed for original lignites.