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This study aims to explore suitable anode materials used in the electrochemical system for indigo dyeing wastewater, to achieve optimal treatment performances.

The single factor experiment was used to explore the optimum process parameters for electrochemical decolorization of indigo dyeing wastewater by changing the applied voltage, electrolysis time and electrolyte concentration. At the voltage of 9 V, the morphology of flocs with different electrolytic times was observed and the effect of electrolyte concentration on decolorization rate in two electrolyte systems was also investigated. Further analysis of chemical oxygen demand (COD) removal rate, anode weight loss and sediment quantity after electrochemical treatment of indigo dyeing wastewater were carried out.

Comprehensive considering the decolorization degree and COD removal rate of the wastewater, the aluminum electrode showed the best treatment effect among several common anode materials. With aluminum electrode as an anode, under conditions of applied voltage of 9 V, electrolysis time of 40 min and sodium sulfate concentration of 6 g/L, the decolorization percentage obtained was of 94.59% and the COD removal rate reached at 84.53%.

In the electrochemical treatment of indigo dyeing wastewater, the aluminum electrode was found as an ideal anode material, which provided a reference for the choice of anodes. The electrodes used in this study were homogenous material and the composite material anode needed to be further researched.

It provided an effective and practical anode material choice for electrochemical degradation of indigo dyeing wastewater.

Combined with the influence of applied voltage, electrolysis time and electrolyte concentration and anode materials on decolorization degree and COD removal rate of indigo dyeing wastewater, providing a better electrochemical treatment system for dyehouse effluent.

To develop electrode materials for supercapacitor with superior electrochemical performance and simple preparation process, the purpose of this study is to prepare flexible CC/NiS/a-NiS electrodes with self-supporting structure by loading hydrothermally synthesized a-NiS particles along with nano-NiS on carbon cloth by electroplating method.

The effects of current densities, temperatures and pH values on the loading amount and uniformity of the active substances during the plating process were investigated on the basis of optimization of surface morphology, crystalline structure and electrochemical evaluation as the cyclic voltammetry curves, constant current charge–discharge curves and AC impedance.

The a-NiS particles on CC/NiS/a-NiS were mostly covered by the plated nano-NiS, which behaved as a bulge and provided a larger specific surface area. The CC/NiS/a-NiS electrode prepared with the optimized parameter exhibited a specific capacitance of 115.13 F/g at a current density of 1 A/g and a Coulomb efficiency of 84% at 5 A/g, which is superior to that of CC/NiS electrode prepared by electroplating at a current density of 10 mA/cm², a temperature of 55°C and a pH of 4, demonstrating its fast charge response of the electrode and potential application in wearable electronics.

This study provides an integrated solution for the development of specifically structured NiS-based electrode for supercapacitor with simple process, low cost and high electrochemical charge/discharge performance, and the simple and easy-to-use method is also applicable to other electrochemically active composites.

This study aims to produce a superhydrophobic fabric surface with a layered rough structure and which are resistant to droplet adhesion. Polydimethylsiloxane (PDMS) systems doped with stearic acid modified titanium dioxide (SA-TiO₂) nanoparticles was sprayed onto the surface of cotton fabric.

This experiment therefore uses a simple method to prepare superhydrophobic textiles by spraying SA-TiO₂ particles mixed with PDMS onto the surface of cotton fabrics. The effects of the ratio of stearic acid to TiO₂, spraying times and tension on the apparent morphological structure and hydrophobic properties of the cotton fabric were investigated.

The results showed that the stearic acid-modified TiO₂ nanoparticles were hydrophobic and more uniformly dispersed in the PDMS solution. When the modification ratio of stearic acid to TiO₂ was 3:5, the water contact angle of cotton fabric was 155.48° and sliding angle was 6.67° under the applied tension for three times of spraying, showing superhydrophobicity. The fabric shows super hydrophobic and anti-adhesive properties to a wide range of liquids such as cola, dyeing liquids, tea, milk and simulated blood. The surface tension of the liquid shows a negative correlation with its adhesion to the fabric.

The SA-TiO₂ and PDMS were applied to the fabric surface by spraying, which not only gave the fabric superhydrophobic properties, but also created anti-adhesion to a wide range of droplets.

The superhydrophobic cotton fabrics prepared by this method showed good anti-adhesive behavior to common stains and simulated blood and can be used in the development of medical protective textiles.

Modification of TiO₂ with stearic acid to prepare SA-TiO₂ with excellent hydrophobic properties, which was mixed with PDMS to make suspensions. Fluorine-free superhydrophobic fabrics were prepared by spraying method. It also exhibited excellent anti-adhesive properties against blood, providing a reference for the preparation of self-cleaning and anti-adhesive surgical gowns.

The purpose of this paper is to invent a new functional coated fabric based on nanomaterials to shield UV and IR. Multifunctional surface coatings with ultraviolet (UV)/near infrared radiations protection and waterproof were widely applied in outdoor fabrics. Herein, ultrafine TiO2 and nano-antimony doped tin dioxide (ATO) were prepared and embedded into water-based polyurethane (PU) coatings and then coated on the nylon fabric.

ATO was prepared using the sol–gel method and the two powders were dispersed by ball milling. The results of zeta potential and particle size distribution showed that the ultrafine TiO2 and nano-ATO could be stably dispersed in water at pH 8 with the presence of sodium polycarboxylate. The optimal process was screened out by orthogonal design and scanning electron microscopy (SEM), UV protection, thermal insulation and water-pressure resistance were tested. SEM images indicated the nanoparticles could be uniformly dispersed in the coatings.

The effect of UV prevention can get to UPF > 50, UVA < 5 per cent, which meet up with the AATCC 183-2014. Coatings can effectively lower the temperature of fabric surface by 8∼9ºC through the self-made closed test system and by 3ºC through the open test system.

These PU coatings are environment-friendly and adhesive to impart waterproof, UV-proof and thermal insulation properties to nylon fabrics by coating finishing.

The purpose of this study is to improve the performance of sodium borohydride in reducing indigo at room temperature, the divalent copper ion complex was combined with electrochemical technology for the reduction of indigo by sodium borohydride.

According to the K/S value of the dyed cloth sample, find a more suitable ligand for the copper ion in the catholyte. Response surface analysis tests were performed to evaluate the effects of sodium borohydride concentration, sodium hydroxide concentration and copper sulfate pentahydrate concentration on the reduction potential of the dye solution and the K/S value of the dyed fabric samples.

Sodium gluconate was found to be a more suitable ligand for copper ions in catholyte. The effects of NaOH concentration as well as the interaction of NaBH₄ and NaOH on the reduction potential of the catholyte and the K/S value of the dyed fabric samples were extremely significant. The optimal concentrations of NaBH₄, NaOH and CuSO₄•5H₂O were 0.5, 2.5 and 0.65 g/L. In the case of the optimized condition, the absolute value of the reduction potential was 968, and the K/S value was 11.92, which is comparable with that of the conventional reduction process with sodium dithionite.

The divalent copper ion complex combined with electrochemical technology was applied in the process of reducing indigo with NaBH₄ at room temperature.

This study aims to evaluate the efficiency of metal electrode and electrolytes on the electroflocculation of indigo wastewater, produced by printing and dyeing factory, and to optimize the treatment system.

For effective purging, various types of metal electrodes (graphite, pure aluminum and stainless steel) and supporting electrolytes (sodium chloride and sodium sulfate) were selected for electroflocculation experiments. The decolorization rate and chemical oxygen demand (COD) removal rate were characterized.

The treatment effects of stainless steel and aluminum were similar, but the dissolution loss of aluminum and the production of flocs greatly limit its application. Electrolytes gave obvious effects to these systems. Sodium sulfate was better than sodium chloride, the decolorization rate was increased by 3.31%, the removal rate of COD in the solution was increased by 28.65% and the weight of flocculation precipitation was reduced by 0.214 g.

The electrochemical treatment system was constructed to compare and analyze the influence of experimental parameters and to provide a reference for the actual treatment of indigo wastewater.

Electrochemical flocculation can remove the insoluble indigo solids and it plays a key role in wastewater treatment.

It is novel to optimize the combination of electrode and electrolyte to improve the efficiency of electroflocculation, which can be widely used in the actual wastewater treatment process.

The purpose of this paper is to investigate the effects of alkali treatment on adhesion of industrial thermoplastic polyurethane elastomer (TPU)/polyester woven fabric inter-ply hybrid composites.

Inter-ply hybrid composites were exposed to varying concentration of sodium hydroxide at different temperature and time and their mechanical properties including differential scanning calorimetry, scanning electron microscope, tensile and peeling strength evaluated to determine optimal treatment parameters.

Modified polyester fabrics treated with alkali had higher tensile and peeling strengths. Accordingly, alkali treatment roughened the surface of polyester fabric, decreasing warp and weft densities, thus increasing fiber surface energy. The fabric had the highest peeling strength of 3.23 N/mm at treatment of 25% concentration of sodium hydroxide (NaOH). Short-term exposure to ultraviolet had little effect on interfacial adhesion of alkali-treated conveyor belt.

Polyester fabric, applied in reinforcing industrial conveyor belts, is never degreased, roughened, sensitized or activated. In this paper, one-step treatment of polyester fabric was performed to increase its adhesion with polyester inter-ply hybrid composites, providing a reference for practical industrial application.

The method developed in this research is simple and provides a solution to improving the interfacial adhesion of TPU/polyester conveyor belt.

The novel alkali treatment technology has many applications in the interfacial performance of composite materials.

In this study, the oxidative degradation performance of indigo wastewater based on electrochemical systems was explored. The decolourization degrees, removal rate of chemical oxygen demand and biochemical oxygen demand of the indigo wastewater after degradation were evaluated and optimized treatment conditions being obtained.

The single factor method was first used to select the electrolyte system and electrode materials. Then the response surface analysis based on Box–Behnken Design was chosen to determine the influence of four independent variables such as FeCl₃ concentration, NaCl concentration, decolourization time and voltage on the degradation efficiency.

On the basis of single factor experiment, the electrode material of stainless steel was selected in the double cell, and the indigo wastewater was electrolyzed with FeCl₃ and NaCl electrolytes. The process conditions of electrochemical degradation of indigo wastewater were optimized by response surface analysis: the concentration of FeCl₃ and NaCl was of 16 and 9 g/L, respectively, with a decolourization time of 50 min, voltage of 10 V and decolourization percentage of 98.94. The maximum removal rate of chemical oxygen demand reached 75.46 per cent. The highest ratio of B/C was 3.77, which was considered to be more biodegradable.

Dyeing wastewater is bringing out more and more pollution problems to the environment. However, there are some shortcomings in traditional technologies such as adsorption and filtration. As a kind of efficient and clean water treatment technology, electrochemical oxidation has been applied to the treatments of various types of wastewater. The decolourization and degradation of indigo wastewater is taken as an example to provide reference for the treatment of wastewater in actual plants.

The developed method provided a simple and practical solution for efficiently degrading indigo wastewater.

The method for the electrochemical oxidation technology was novel and could find numerous applications in the degradation of printing and dyeing wastewater.

This study aims to evaluate the thermal performance of phase change materials (PCMs) microcapsules (MCs) attached using SiO₂ microspheres and investigate the thermal regulation effect on the coated denim fabric.

The PCM microcapsule was prepared by in situ polymerization using a mixture of solid paraffin and butyl stearate as core material (CM) and methyl methacrylate as a monomer. The SiO₂ microparticles were attached to the outer layer of the membrane to enhance the thermal performance of MCs. The morphology, chemical structure, latent heat storage and thermal resistance of MCs were characterized. PCM MCs were coated on the denim fabric and thermo-gravimetric analysis was conducted; thermal insulation and thermal infrared imaging performance of the coated fabrics were also investigated.

The diameters of SiO₂ particles and PCMs MCs were 300-500 nm and 1 μm, respectively. SiO₂ was wrapped on single-wall PCMs MCs with the mass ratio of 1:5. With the addition of SiO₂, the phase transition temperature range of MCs increased from 34°C to 39°C, and the endothermic and exothermic latent heat decreased by 5.35 J/g and 10.07 J/g, respectively. The degradation rate of MCs was significantly slowed down at high temperature. The denim fabric coated with MCs revealed thermal regulation property. After absorbing heat, the MCs slowed down the rate of heat loss and extended the heat release time.

The phase transition temperature of the composite CM was wide, and the latent heat storage was reduced. The addition of SiO₂ particles can significantly slow down the rate of heat loss, but it further reduces the latent heat storage performance.

The method developed provided a simple and practical solution to improve the thermal regulation performance of fabrics.

The method of adjusting the phase transition temperature range of the composite CM is novel and many applications could be found in preparation of PCMs and thermal management.

To improve the problems as the heavy burden of sewage treatment and environmental pollution caused by the traditional sodium hydrosulfite reduction dyeing of indigo, this study aims to carry out the direct electrochemical reduction dyeing for indigo with the eco-friendly Cu(II)/sodium borohydride reduction system under normal temperature and pressure conditions.

The electrochemical behavior of Cu(II)/sodium borohydride reduction system was investigated by cyclic voltammetry. And, the dyeing performance of the Cu(II)/sodium borohydride reduction system was developed by optimizing the concentration of copper sulfate in the anode electrolyte, applied voltage and reduction time via single-factor and orthogonal integrated analysis.

The dyeing performance of the Cu(II)/sodium borohydride reduction system is superior to that of the traditional reduction dyeing with sodium hydrosulfite. In the case of the optimized condition, the soaping fastness and dry/wet rubbing fastness of the dyed fabric in the two reduction dyeing processes were basically comparable, the K/S value of electrocatalytic reduction of indigo by Cu(II)/NaBH4 is 11.81, which is higher than that obtained by traditional sodium hydrosulfite reduction dyeing of indigo.

The innovative electrocatalytic reduction system applied herein uses sodium borohydride as the hydrogen source combined with Cu(II) complex as the catalyst, which can serve as a medium for electron transfer and active the dye molecule to make it easier to be reduced. The electrochemical dyeing strategy presented here provides a new idea to improve the reduction dyeing performance of indigo by sodium borohydride.