Transfer and Friction Characteristics of Sports Socks Fabrics Made of Synthetic Fibres in Different Structures

Sports socks fabrics produced from polyester, polypropylene, their modified forms Thermocool®, Polycolon®, in three different structures (single jersey, piquet, terry) were investigated for their skin-fabric friction, permeability (air and water vapour), liquid absorption and transfer (absorbency, immersion, absorption capacity, wetback and drying) properties. According to the results, the effect of structure is dominant for frictional characteristics but focusing on the material, polypropylene created a bulkier and lighter structure with lower friction coeffi¬cients, an advantage for sports socks. The effect of structure is greater than the material also for some thermal comfort parameters, e.g. air permeability and absorbency. Focusing on materials, besides their better liquid transfer characteristics, modified forms of both fibres had worse performances for air permeability and absor¬bency compared to their standard forms. Absorption capacity, wetback and drying performances were related to fabric density besides the polyester’s higher regain capacity. While Polycolon® had superiority for wetback performance against standard polypropylene, this was not the case for Thermocool®; however, both modified materials showed apparent superiority for drying periods. Piquet structures were advantageous for absorption capacity and wetback performances for polypropylene. For sports socks parts, specific needs can be met by changing the fabric structure. Considering the materials, polypropylene and Polycolon® can be recommended for both thermal and tactile aspects.

The Natural Durability and Drying Properties of Ganitri Wood (Elaeocarpus sphaericus Schum)

Ganitri (Elaeocarpus sphaericus Schum.) is a fast-growing species that was majority planted in community-based forets in Java. This research aimed to evaluate the natural durability and drying properties of ganitri wood, hence the best uses of the wood can be achieved. The wood durability was tested in laboratory and field scales based on SNI 7207:2014 and ASTM D 1758-02 standards respectively, while the wood treatibilty evaluation used soaking method with 5% borax preservative. The wood drying property was assessed through oven drying at 100°C temperature based on Terazawa method. The resistance of the wood against subterranean termites Coptotermes curvignathus is classified as durability class IV. Ganitri wood was very easy to be preserved with the cold soaking method. Boron retention in ganitri was 22.87 kg.m-³, while its penetration was 27.80 mm or 94.24%. Ganitri had rather poor drying properties, which was prone to surface check. The proper drying for ganitri wood was suggested using initial and final temperatures 53°C and 83°C, respectively, while the initial and final relative humidity were 85% and 30%.

Integration of Safety Aspects in Modeling of Superheated Steam Flash Drying of Tobacco

Knowledge of the drying properties of tobacco in high temperatures above 100 °C and its dust are crucial in the design of dryers, both in the optimization of the superheated-steam-drying process and in the correct selection of innovative explosion protection and mitigation systems. In this study, tobacco properties were determined and incorporated into the proposed model of an expanding superheated steam flash dryer. The results obtained from the proposed model were validated by using experimental data yielded during test runs of an industrial scale of a closed-loop expansion dryer on lamina cut tobacco. Moreover, the explosion and fire properties of tobacco dust before and after the superheated steam-drying process at 160, 170, 180, and 190 °C were experimentally investigated, using a 20 L spherical explosion chamber, a hot plate apparatus, a Hartmann tube apparatus, and a Godbert–Greenwald furnace apparatus. The results indicate that the higher the drying temperature, the more likely the ignition of the dust tobacco cloud, the faster the explosion flame propagation, and the greater the explosion severity. Tobacco dust is of weak explosion class. Dust obtained by drying with superheated steam at 190 °C is characterized by the highest value of explosion index amounting to 109 ± 14 m·bar·s−1, the highest explosion pressure rate (405 ± 32 bar/s), and the maximum explosion pressure (6.7 ± 0.3 bar). The prevention of tobacco-dust accumulation and its removal from the outer surfaces of machinery and equipment used in the superheated steam-drying process are highly desirable.

Structural Impact on Some Common Physical Properties of Single Jersey Weft Knit Fabric

Single jersey weft knit fabrics include a large portion of knitted products. These fabrics are made using different types of stitches. In this study, several single jersey weft knit fabric samples containing four courses and two wales in the repeating unit of the fabric structure were made by introducing and gradually increasing the number of tuck stitches in the structure, to find out the effect of this stitch on fabric properties. Results showed that tuck stitches could positively affect the areal density, width, and tensile properties of the fabric. For some comfort-related properties, tuck stitches were found to improve wicking and drying properties, reduce water vapor transmission rate, and affect fabric smoothness. The position of tuck stitches in the structure also had some effect, but was not as significant as when the number of tuck stitches was varied.

Environmental Conditions Affecting Ochratoxin A During Solar Drying of Grapes: The Case of Tunnel and Open Air-Drying

Drying optimization, to mitigate fungal growth and Ochratoxin A (OTA) contamination is a key topic for raisin and currant production. Specific indicators of environmental conditions and drying properties were analyzed using two seedless grape varieties (Crimson—red and Thompson—white), artificially inoculated with Aspergillus carbonarius under open air and tunnel drying. The air temperature (T), relative humidity, grape surface temperature (Ts) and water activity throughout the drying experiment, the grapes’ moisture content and the fungal colonization and OTA contamination during the drying process and their interactions were recorded and critically analyzed. Drying properties such as the water diffusivity (Deff) and peel resistance to water transfer were estimated. The grapes Ts was 5–7 °C higher in tunnel vs. open air–drying; the infected grapes had higher maximum Ts vs. the control (around 4–6°C). OTA contamination was higher in tunnel vs. open air–dried grapes, but fungal colonies showed the opposite trend. The Deff was higher in tunnel than in the open air–drying by 54%; the infected grapes had more than 70% higher Deff than the control, differences explained by factors affecting the water transport. This study highlighted CFU and OTA indicators that affect the water availability between red and white grapes during open air and tunnel drying, estimated by the Deff and peel resistance. This raises new issues for future research.

Novel Mangosteen-Leaves-Based Marker Ink: Color Lightness, Viscosity, Optimized Composition, and Microstructural Analysis

Dry mangosteen leaves are one of the raw materials used to produce marker ink. However, research using this free and abundant resource is rather limited. The less efficient one-factor-at-a-time (OFAT) approach was mostly used in past studies on plant-based marker ink. The use of statistical analysis and the regression coefficient model (mathematical model) was considered essential in predicting the best combination of factors in formulating mangosteen leaf-based marker ink. Ideally, ink should have maximum color lightness, minimum viscosity, and fast-drying speed. The objective of this study to study the effect of glycerol and carboxymethyl cellulose (CMC) on the color lightness and viscosity of mangosteen-leaves-based marker ink. The viscosity, color lightness, and drying properties of the ink were tested, the significant effect of glycerol and CMC (responses) on ink properties was identified and the prediction model on the optimum value of the responses was developed by using response surface methodology (RSM). The microstructure of mangosteen leaves was analyzed to study the surface morphology and cell structure during dye extraction. A low amount of glycerol used was found to increase the value of color lightness. A decrease in CMC amounts resulted in low viscosity of marker ink. The optimum formulation for the ink can be achieved when the weight percents of glycerol, benzalkonium chloride, ferrous sulphate, and CMC are set at 5, 5, 1, and 3, respectively. SEM micrographs showed the greatest amount of cell wall structure collapse on samples boiled with the lowest amount of glycerol.

EFFECT OF DRYING RATE AND MOISTURE REMOVAL ON THE DRYING PROPERTIES OF GROUND AND FERMENTED CASSAVA MASH ("GARI")

Drying characteristics of ground and fermented cassava mash called "gari" (a carbohydrate and staple food in Nigeria) were studied. Several properties such as drying rate, thermal conductivity, thermal diffusivity, specific heat capacity, and bulk density were investigated during the roasting of the mash. These properties were discovered to be influenced by the removal of moisture as the mash dries. The optimum initial moisture content was 46 % wb at 60 % Rh. The roasting chamber reaches a steady state temperature of 160 oC in 12 minutes before roasting while 5 kg of the wet cassava mash dried to a final moisture content of 9.8 % wb in 21 minutes. It was observed that as the moisture content reduces from 46 % to 9.8 %, the bulk density increased from 441.32 kg/m3 to 507.91 kg/m3, drying rate reduces from 2.64 to 0.54 kg/min and specific heat capacity reduces from 4.14 to 2.01 kJ/(kgK). The effects of the moisture removal on the studied parameters were thus discussed as the mash dries along the length of the dryer.