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Recycling of photocatalyst in wastewater treatment is a big challenge. Fixation of photocatalyst on a flexible surface of solid substrates is a promising solution. In this work, copper ferrite (CuFe2O4) particles were loaded onto polydopamine (pDA) pretreated ceramic/polyester fabrics (CPF) via coprecipitation. The CPF not only acts as loading material for CuFe2O4 particles, but also makes this photocatalyst convenient to recycle. The morphology, elemental composition and structure of the as-fabricated CPF/CuFe2O4 were characterized by scanning electron microscope (SEM), Fourier transform Infrared (FT-IR) spectrometer, X-ray photoelectron spectroscopy (XPS) and X-ray diffractometer (XRD). The degradation rate of methylene blue (MB) by the CPF/CuFe2O4 photocatalyst reached to 98.2% under visible light irradiation for 80 min, reflecting the excellent photocatalytic activity of the composites. The CPF/CuFe2O4 demonstrated good photostability and recoverability, indicating its great potential in wastewater treatment. Moreover, the degradation mechanism and possible degradation pathway of MB by CPF/CuFe2O4 photocatalyst were investigated.

Yarn-based strain sensor is an emerging candidate for the fabrication of wearable electronic devices. The intrinsic properties of yarn, such as excellent lightweight, flexibility, stitchability, and especially its highly stretchable performance, stand out the yarn-based strain sensor from conventional rigid sensors in detection of human body motions. Recent advances in conductive materials and fabrication methods of yarn-based strain sensors are well reviewed and discussed in this work. Coating techniques including dip-coating, layer by layer assemble, and chemical deposition for deposition of conductive layer on elastic filament were first introduced, and fabrication technology to incorporate conductive components into elastic matrix via melt extrusion or wet spinning was reviewed afterwards. Especially, the recent advances of core–sheath/wrapping yarn strain sensor as-fabricated by traditional spinning technique were well summarized. Finally, promising perspectives and challenges together with key points in the development of yarn strain sensors were presented for future endeavor.

Novel water and dye-free heat treatment method was used to color wool yarn. The heat treatment can not only give the white wool yarn new color but also minimize the yarn hairiness. The influences o...

This article is focused on a novel method to color wool fabric via heat treatment under an inert atmosphere. It can not only give new color to the fabric but also minimize pollution, because it is water and dye-free. The effects of temperature, time and different inert atmospheres (nitrogen, argon) used in the heat treatment on wool fabric color were studied. The bending stiffness, the crease recovery angle and tensile testing were used to analyze the mechanical properties of wool fabric before and after heat treatment. The color fastness to soaping and light of wool fabric after inert atmosphere heat treatment were compared with that of traditional basic yellow dyed wool fabric. The results showed that the K/ S value of wool fabric treated with a nitrogen and argon atmosphere increased with the increasing temperature and time. Under the same heat treatment conditions, the maximum K/ S value of fabric heat treated under nitrogen was higher than that under argon. The bending stiffness and crease recovery angle performance were improved and positively correlated with the heat treatment temperature and time. The samples treated under the same conditions under nitrogen showed higher bending stiffness and a lower crease recovery angle than under argon. The contact angle of the wool fabric after the treatment would decrease first and then increase with the increasing temperature. The tensile strength of the wool fabric would decrease with increasing temperature and time of the heat treatment in both nitrogen and argon, and the tensile strength of the wool fabric after treatment was higher than 80% of the original tensile strength, although the breaking elongation decreased. The color fastness to soaping and light of wool fabric after inert atmosphere heat treatment were better than for the traditional basic yellow dyed wool fabric. Therefore, the use of inert atmosphere heat treatment to endow wool fabric color is a potential research direction.

Aiming at the utilization of regional mining wastes including iron tailings sand and coal gangue (CG), a novel coal gangue-filled backfill (CGFB) is proposed in this paper, which is achieved by casting the self-consolidating cement-tailings grout (CTG) into pre-placed CGs skeleton. The mixture proportions of self-consolidating CTGs were first designed based on the rheological properties by adding viscosity enhancing agents (i.e. hydroxypropyl methylcellulose and polyacrylamide) and polycarboxylate superplasticizer (PCE). As a consequence, the static stabilities and filling abilities of fresh CTGs were also strengthened. The filling ability of fresh CTGs is a flowability-related parameter and can be reflected by the surface bugholes of hardened CGFBs. The results indicate that the use of CTG with flow diameter > 25 cm and flow time

Yarn-based wearable sensors have attracted attention, but it is difficult to fabricate yarn strain sensors with large-scale production, weavability, dyeability and durability toward real applications as wearable electronics and smart textiles. Herein, we report a facile core spun strategy to fabricated spandex/CNT cotton yarns (SCCY) on an industrial spinning machine. For the first time, wearable sensor could be dyed through a simple dip dyeing process with different colors (red, yellow, blue and black). The unique core-sheath structure endowed the yarn with good sensitivity (gauge factor of 21.85 at 300% strain), broad sensing range (0%-300% strain), excellent durability (against dip dyeing, washing, acid and alkali) and abrasion resistance (resistance change 5% after rubber 100 cycles). The sensor yarn was also successfully woven/knitted into textiles and it could be sewn into a fabric. The weavable and dyeable core-spun yarn in the present work provide a feasible way for industrial-scale manufacture wearable sensors.

Gold nanoparticles (AuNPs) were synthesized in situ on cotton, one of the most popular cellulose materials, to achieve functionalization. The localized surface plasmon resonance of the AuNPs imparted the cotton fabric with colors, showing good colorfastness to washing and rubbing. Characterization of the surface morphology and chemical composition of the modified cotton fabric confirmed synthesis and coating of the AuNPs on cotton fibers. The relationship between the morphology of the AuNPs and the optical properties of the cotton fabric was analyzed. Acid condition enabled in situ synthesis of AuNPs on cotton. Cotton with AuNPs exhibited significant catalytic activity for reduction of 4-nitrophenol by sodium borohydride, and could be reused in this reaction. Treatment with AuNPs substantially improved the ultraviolet (UV)-blocking ability of the fabric and resulted in cotton with remarkable antibacterial activity. Traditional reactive dyes were applied to the cotton with AuNPs to enhance its color features. The catalytic properties of the AuNPs on the fabric were not influenced by dyeing with traditional dyes. AuNP-treated cotton fabric used as a flexible active substrate showed improved Raman signals of dyes on the fabric.

In this study, a single firing was used to convert stabilized polyacrylonitrile (PAN) fibers and ceramic forming materials (kaolin, feldspar, and quartz) into carbon fiber/ceramic composites. For the first time, PAN carbonization and ceramic sintering were achieved simultaneously in one thermal cycle and the microscopic morphologies and physical features of the obtained carbon fiber/ceramic composites were characterized in detail. The obtained carbon fiber/ceramic composite showed comparable flexural strength as commercial ceramic tiles. Meanwhile, the composite showed exceptional electro-thermal performance based on the electro-thermal performance of the carbonized PAN fibers, which could reach 108 ℃ after 15 s, 204 ℃ after 90 s, and 292 ℃ after 450 s at 5 V (2.6 A), thereby making the ceramic composite a good candidate as an indoor climate control heater, defogger device, kettle, and other heating element.

Two independent heating steps are currently involved for fabricating carbon fiber/ceramic composites, which include carbonization of fibers and ceramization of ceramic precursors with carbonized fibers together. In this work, silk fabric and silkworm cocoon were used as carbonaceous precursors for fabricating carbonized fiber/ceramic composites through one-step heating processing. This one-step manufacturing method achieved both the carbonization of silk fabric/silkworm cocoon and the formation of mullite simultaneously under nitrogen environment. The as-prepared composite based on three-layer silk fabric reached over 100 °C after 30 s when a voltage of 10 V was applied, and achieved a stabilized temperature of 239 °C after 540 s. The obtained composites also showed stable cyclic heating property, homogeneous heat distribution and electromagnetic shielding properties. These results implicate the great potential for the developed silk-ceramic composites and inspire the further design of silk-based materials for electro-thermal conversion.

DNA methylation, catalyzed by DNA methyltransferases (MTases), is a key component of genetic regulation, and DNA MTases have been regarded as potential targets in anticancer therapy. Herein, based on our previously developed DNA-mediated supercharged green fluorescent protein (ScGFP)/graphene oxide (GO) interaction, coupled with methylation-initiated template- free DNA polymerization, we propose a novel fluorescence assay strategy for sensitive detection of DNA MTase activity. A hairpin DNA with a methylation-sensitive site and an amino-modified 3'-terminal (DNA-1) was designed and worked as a starting molecule. In the presence of DNA MTase, methylation-sensitive restriction endonuclease, and terminal deoxynucleotidyl transferase (TdT), DNA-1 can be sequentially methylated, cleaved, and further elongated. The resulting long DNA fragments quickly bind with ScGFP and form the ScGFP/DNA nanocomplex. Such nanocomplex can effectively protect ScGFP from being adsorbed and quenched by GO. Without the methylation-initiated DNA polymerization, the fluorescence of ScGFP will be quenched by GO. Thus, the DNA MTase activity, which is proportional to the amount of DNA polymerization products, can be measured by reading the fluorescence of ScGFP/GO. The method was successfully used to detect the activity of DNA adenine methylation (Dam) MTase with a wide linear range (0.1–100 U/mL) and a low detection limit of 0.1 U/mL. In addition, the method showed high selectivity and the potential to be applied in a complex sample. Furthermore, this study was successfully extended to evaluate the inhibition effect of 5-fluorouracil on Dam MTase activity and detect TdT activity.

A core-sheath nanocomposite yarn, with CNT/cotton composite yarn (CCY) as the core and nanofibrous polyurethane/temperature sensitive ink as the sheath, was fabricated to generate highly robust and durable electro-thermochromic performance. Due to its novel core-sheath nanocomposite structure, the as-fabricated electro-thermochromic composite yarn (ECCY) brought together the excellent mechanical properties and electrothermal properties together with electrochromic performance. The ECCY exhibited excellent electrified heating performance with stability even after 100 cycles of heating/cooling. Moreover, the ECCY showed excellent durability against repeated bending, twisting and stretching, washing and even soaking in acid and alkali solutions. The color of ECCY was successfully tuned via changing the applied current. In addition, the ECCY was used to design different patterns and to form a fabric, resulting in color conversion patterns/fabrics when applying/releasing a current. This work provides a novel strategy of developing electro-thermochromic composite yarn by designing the core-sheath micro-nano fibrous composite structure. The highly robust and durable performance of yarn will benefit its applications as wearable electronics.

With fiber-based wearable electronics being developed and widely used in various fields, the safety and durability of nanomaterials in fibrous system become big concerns due to the leakage of nanomaterials and possible failure in functionality. To date, it is still challenging to fabricate wearable strain sensors with sensitivity and durability. Herein, we report a simple strategy for large-scale fabrication of core-sheath nanocomposite yarn (CSCY) based wearable sensor with high sensitivity and superior durability. By dispersing aqueous CNT ink into braided composite yarns as the core (BYs-CNT) and electrospun polyurethane (PU) nanofibers as the sheath, a unique core-sheath micro-nanofibrous structure was fabricated to grant the yarn with extremely high sensing sensitivity (maximum GF up to 980), long-term stability and great durability (against washing and dilute hydrochloric acid). The as-developed CSCY strain sensor was demonstrated to monitor real-time subtle and vigorous human activities. The present work provides insights for developing reliable and stable, highly sensitive, flexible and durable wearable electronics with potential applications in different areas.

A label-free and convenient strategy for PARP-1 activity assay and inhibitors assessment has been developed based on the fluorescence resonance energy transfer (FRET) between a cationic conjugated polymer (CCP) and supercharged green fluorescent protein (scGFP).

To perform bending fatigue tests on fiber materials, a specially designed bending fatigue test apparatus has been developed. The test apparatus was equipped with a temperature control system and a Xenon lamp irradiation system, and thereby the test can be done in controlled environments such as temperature and light irradiation conditions. Using this apparatus, bending fatigue tests on Kevlar 49 and PBO fibers were performed. The test results showed that the bending fatigue strength of Kevlar49 and PBO fibers was strongly influenced by temperature and light irradiation. The σ–N and σ–lnN curves indicated that the pre-tension had significant effects on the bending fatigue life and the fatigue life decreased when temperature became high. In addition, the fatigue strength of fibers tested with light irradiation was lower than that without light irradiation.

A conductive composite was designed and fabricated by combining cotton fibers and ceramic precursors (kaolin, feldspar and quartz) in a one-step firing process. The firing process achieved the carbonization of cotton fibers and ceramicization of inorganic precursors simultaneously under a nitrogen environment. The prepared cotton/ceramic composite materials exhibited significant electro-thermal effect and overload protection function. The obtained composite based on 64 single cotton yarns reached more than 100 °C at 10 V (0.518 A) after 20 s and showed reliable cyclic heating performance. Carbonized cotton showed better electro-thermal performance than rayon, which could reach a maximum temperature of 188 °C at 10 V (0.518 A) after 6 min. The composites could power-off automatically at a high voltage, which is useful for circuit breakers or high temperature protection device. Furthermore, the maximum temperature from electro-thermal conversion for the composites can be adjusted by controlling the operating voltage and cotton to rayon ratio. The great electro-thermal features and strong mechanical properties make the composite a good candidate for in-door temperature control. Keywords: One-step firing process, Carbonized cotton, Ceramic, Composite, Electro-thermal performance

The interaction between supercharged green fluorescent protein (ScGFP) and graphene oxide (GO) as well as the resulting quenching effect of GO on ScGFP were investigated. Based on this unique quenching effect and the DNA-mediated ScGFP/GO interaction, a label-free fluorescence method has been established for homogeneously assaying the activity and inhibition of base excision repair enzyme.