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Due to the particular physiological conditions of the human body, activity in cold weather condition is of great importance and needs unique thermal clothing. In this research, three-layered heating fabrics were designed and woven to analyze their performance in cold climates. The samples consist of three types of heating elements (nickel-chrome, tungsten, and aluminum-chrome) and two different states for embedding the heating elements in the fabric structure. In order to investigate the effect of voltage on the heat flux and maximum temperature, all specimens were subjected to two voltage levels of 9 and 12 V for 10 min, the process of heat production, the influence of structural factors on the flux and temperature and also the thermal efficiency was analyzed. In addition, in order to select the optimum sample, the amount of required energy for maintaining body comfort was calculated based on the theoretical equations at the ambient temperatures of −5 and −10°C. The results showed that the woven sample using tungsten elements and the weft-to-element ratio of 12 had the desirable heating performance and could maintain the skin surface temperature around the thermal comfort zone.

In this paper, nylon 66/TiO2 composite nanofiber yarn has been developed using electrospinning method. The effect of the TiO2 nanoparticle content on the physical and tensile properties of the resulted composite nanofiber yarns has been extensively investigated using SEM, EDX, FTIR and mechanical testing machine. The probability density function is computed to model the diameter distribution of nanofibers constituent of the composite yarn for different percentages of TiO2. The addition of TiO2 nanoparticles into the electrospun composite nanofiber yarn decreases its tensile strength. The influence of thickness (diameter) and twist of the yarn on its tensile strength has been considered and the optimum conditions with improved tensile strength have been presented. Photoactivity of the composite yarns is tested against Rhodamine B (RhB). Results show that nanocomposite yarns are effective to be used as an economically and environmentally friendly photocatalyst in water remediation processes. They are not dispersed in the solution and can be removed easily without additional and costly steps of filtration or centrifuge.

Achieving whiteness and opaqueness has been an issue in paint, ceramic, paper, and coating industries from the very beginning. In the past two decades, biomimetics, for the construction of bio-inspired functional materials, has attracted much attention. As an application of biomimetic science, various structural colored materials are investigated by many researchers. The white beetle exoskeletal scales is one of those materials that shows a brilliant white color caused by randomly arranged chitin nanofibers. This material is the inspiration for achieving light weight, efficient, and low-cost white coatings by means of a nanostructure. We used this idea in this research to apply nanofibrous polymeric layer on a substrate, paper sheet in here, and witnessed the possible achievements by varying the nanofiber layer characteristics that underpin its optical properties. We coated nylon and PAN nanofiber layers on the surface of a paper using an electrospinning method and for both polymers desirably high whiteness and opaqueness achieved. Moreover, it was observed that end-use application in printing and writing is easily attained on the nanofiber-coated paper using the common methods. Measuring the properties of the nylon nanofiber-coated paper showed that the tensile strength and hydrophilicity slightly increased depending on the nanofiber layer characteristics.

This paper reports a fast, accurate, and non-destructive three-dimensional imaging approach based on using quantum dots and confocal laser scanning microscopy to get three-dimensional images of internal pore structure of the nanofibrous materials. A practical method of making the fiber fluorescent using quantum dots was applied before three-dimensional imaging by confocal laser scanning microscopy. Fibrous scaffolds with different porosity parameters produced by electrospinning and their three-dimensional pore structure was evaluated by this approach. Furthermore, the introduced approach can be used to measure the pore interconnectivity of the scaffold.