Thermophysiological comfort properties of selected knitted fabrics and design of T-shirts

Thermal comfort is one of the most important components of comfort which shows physiological, psychological, and physical harmony between human body and environment. The heat and moisture transfer capacity of fabric from skin to environment affects the thermal comfort of garments. The transfer capacity depends on the characteristic features of raw materials and fabric structural properties. In this study, it is aimed to determine the advantages of knitted fabric types, taking into account the environmental condition and activity level by measuring the thermal comfort properties such as air permeability, wicking, moisture management, thermal and water vapor resistances. Two knitted structures composed of tuck and float combinations and six raw materials were chosen for the fabrics produced. According to the measurement results, the polyester and cotton/Coolmax fabrics with float stitches have had good liquid moisture transport properties. Besides, high air permeability and low water vapor resistance have been obtained in viscose and Tencel LF fabrics with tuck stitches. On the basis of the results obtained in this investigation, and taking into consideration thermal behavior of human body, four women’s and five men’s T-shirts are designed. These T-shirt designs may be helpful for further approaches on the optimization of thermal comfort for sports activities in hot environment.     

Effects of probiotic bacteria and oils on fatty acid profiles of cultured cream

The aim of this study was to determine the effects of using various probiotic bacteria and plant oils in cultured cream on the fatty acid profiles including conjugated linoleic acids (CLA). L. acidophilus, B. bifidum, S. thermophilus and L. bulgaricus, P. thoenii (jensenii) P126, and P. jensenii B1264 and a mixed culture (blend of L. acidophilus, B. bifidum, S. thermophilus and L. bulgaricus) were used in the fermentation of cream samples at a level of 2%. Cream samples were fortified with sunflower oil, soybean oil and hazelnut oil at a level of 2%. Microbial counts and fatty acid profile analysis were performed. The microbial results demonstrated that fermented cream could be a superior product for the presence of probiotics. Even though the cream samples contained 52% milk fat, in the majority of the samples growth of probiotic bacteria was higher than 10⁶ cfu/g. Concentrations of short‐chain fatty acids such as butyric, caproic and capric acids in cultured cream samples differed depending on the cultures used, while long‐chain unsaturated fatty acids were significantly affected by the plant oil fortification. The highest CLA content was obtained in the sample produced with B. bifidum, containing 0.73 mg of CLA/g fat. The effect of different plant oils on CLA concentration was significant (p >0.05) for HO + YC, SFO + LBYC and SO + LBYC. Results of the study are important for the dairy industry since it is the first publication on fermented cream with improved functional properties. The development of functional cultured cream with plant oils and probiotic bacteria would provide an important alternative dairy product.     

Effects of SiC particles size on electrochemical properties of electroless Ni-P-SiC nanocomposite coatings

Silicon carbide (SiC) nanoparticles were co-deposited by electroless deposition in nickel-phosphorous (Ni–P) acidic bath. In order to understand the size effect of SiC nanoparticles on the electrochemical properties of the coatings, SiC nano particles with different size (20, 50 and 200 nm) in 2 g/L concentration was added to the bath. All samples was heat treated in 400°C in order to obtain crystalline structure. Potentiodynamic polarization and electrochemical impedance spectroscopy was employed to examine of corrosion performance of the coatings. X-ray diffraction (XRD) and Scanning Electron Microscopy (SEM) were used for phase and morphological studies, respectively. Experimental results show that SiC particles size in the coating bath affected both composition and morphology of the coating. Presence of SiC nanoparticles in the Ni–P coating with 50 nm increased the corrosion resistance of the coating more than the other sizes.