Fractal structure and hydration-driven shape memory of duck down in the dry–wet state

Duck down, as a natural keratin material, has been widely used as a filling material. The multilevel bifurcation structure of down has been observed and characterized through scanning electron microscopy. The structure is a complex fractal structure composed of four-level self-similar structures including five units, that is, the calamus, main barb, barb, barbule, and node or prong. The differential friction effect of the dynamic friction coefficients of the barb was reduced from 0.4 (dry state) to 0.23 (wet state), namely a decrease of 42.5%. The friction locking effect decreases due to the swelling of the fiber diameter. The down is zero gravity in water, and under the action of vibration and internal stress, down that has been subjected to friction or heat setting treatment can quickly return to its original shape in water. This shape memory mechanism was further confirmed, in which down after heat setting can restore its shape to the natural state by shaking it quickly and vigorously. This research provides inspiration to investigate more complicated functions of natural materials and encourages the creation of very intelligent synthetic polymers.

Heat setting system development of bridge floor surface using low temperature geothermal energy

Multilevel transport interchanges play a decisive role in the road infrastructure both throughout the world and in Russia. Significant problems of the safe operation of multi-level highways in the general metropolitan traffic system and the country territory, in general, are associated with the need to thoroughly clear them of snow and ice during winter and off-season periods. The simplest, most obvious, and historically proven non-mechanical ice control method is using the chemical reagents mixtures. Despite the fact that the quality of the original anti-ice chemical products is constantly being improved, the reagents composition is updating, the target operation remains unchanged — a decrease in the ice and snow melting temperature point. Unfortunately, in the process of melting with heavy snowfall, the concentration and, accordingly, the brine viscosity increases, leading to «oiling» of the asphalt pavement, thereby worsening the already difficult situation on the road. One of the attractive ways to keep the roadway in proper condition is to heat it to get rid of ice. Direct heating methods such as central heating or electric heating are too costly and economically unfeasible. It seems promising to use low-temperature geothermal energy, which will significantly reduce energy costs and increase the transport projects’ economic attractiveness. This work is devoted to the study of the practical applicability of the bridge floor surface heat setting technology using low-temperature geothermal energy as part of the «Best available technologies» concept implementation in accordance with GOST R 56828.15-2016 in terms of infrastructure facilities energy efficiency. Based on the work results, the authors provide the study results and numerical modeling, as well as their comparison. The results presented in this article are a part of the dissertation research «New technological solutions development for the bridge floor surface at transport interchanges» Kostenko S.А.

Analysis of potential waste heat recovery from a stenter in a textile plant

The textile sector, an important economic driving force in Antioquia, Colombia, uses great quantities of thermal energy mainly produced by coal combustion, which holds enormous potential for recovery. One of the most common processes in a textile plant is heat setting, which uses a significant amount of thermal energy to adjust the properties of fabrics, such as shrinking, stiffness, pull strength, width, and stretching. In this study, we calculate the mass and energy balances of a stenter and propose a system to recover the energy available in its exhaust gases. The energy recovery potential in this heat setting process is 800.97 kW, which represents 87.2% of the total input energy. Additionally, we evaluate different heat exchangers to recover the available heat and present criteria to select them. Finally, thermosyphons, whose thermal efficiency was theoretically determined here, offer a promising alternative for heat recovery from actual stenters.

RANCANG BANGUN ALAT TERAPI ELEKTRIK UNTUK MEMBANTU PENYEMBUHAN CEDERA DI POLI FISIOTERAPI RSUD Dr SOEDOMO TRENGGALEK

An injury is a disorder that occurs in the body which results in the appearance of redness, pain, swelling and the inability to function properly in the limbs. Handling of minor to severe injuries is carried out with medical treatment such as surgery or traditional medicine, but this treatment has not provided any assurance of healing, as for the alternative treatment, namely heat therapy. Heat therapy is able to open blood vessels wider and can provide a supply of oxygen and nutrients to reduce pain in injured sufferers. From this research, it can be produced a design of an electric therapy device that can produce heat equipped with a heat setting and a therapy time controller. The design of an electric therapy device to help heal physiotherapy dipole injuries at Dr. SOEDOMO Trenggalek Hospital has several advantages, namely that it can generate heat according to temperature settings, can adjust the length of therapy process time according to time settings and can also provide a display of temperature and time on the LCD display. The results of research on this electric therapy device are able to work according to predetermined working principles.

Thermal behaviour of heat treated polyester knitted fabrics

Purpose Thermoplastic polymer fabrics are normally heat set to make them dimensionally stable. These fabrics in garment panel form may again be exposed to heat during the processes such as bonding, sublimation printing and cause to change their dimensions. The purpose of this paper is to investigate the response of polyester yarns in knitted fabrics to heat setting and post-heat treatments. Design/methodology/approach In this study, the thermal shrinkage behaviour of heat set polyester knitted fabrics when subjected to post-heat treatment processes are analyzed using differential scanning calorimetry (DSC) and analysis of fabric shrinkage. DSC is a thermo-analytical technique that measures the difference in the amount of heat needed to increase the temperature of the sample and the reference. A heat flux versus temperature curve is one of the results of a DSC experiment. The polymer structure and morphology of polyester heat-treated and post-heat–treated fabrics were determined by examining the DSC thermograms. Findings Heat setting and post-heat setting causes the effective temperature of polyester to change. Effective temperature occurred around 160°C for fabrics heat set at low temperatures and increases as the heat setting temperature increases. Post-heat treatments cause to elevate the effective temperature. Shrinkage of fabrics below the effective temperature is not statistically significant while the shrinkage at higher temperatures is significant. Effective temperature is the main determinant of thermal shrinkage behaviour of polyester. Originality/value The study reveals the significance of the effective temperature of polyester on heat treatments and post-heat treatments. The study revealed that heat-setting temperature is a primary determinant of the thermal stability of polyester fabric that are subjected to heat treatments.