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Selective Laser Melting (SLM) is an increasingly concerned trend in Ti-6Al-4V blade manufacturing, while the SLMed Ti-6Al-4V blade cannot be used directly because of poor surface integrity and high residual stresses. Precise machining after SLM is a feasible solution but also a challenge. The low rigidity of the blade will lead to deformation when machining. The deformation can lead to surface error and may make defect parts. Two-steps machining processes to address the problems were proposed in this paper. First, a non-uniform allowance distribution was allocated and optimized in semi-finishing based on Ritz solution to elastic deformation. The blade was simplified as a cantilever thin plate with various thickness, and the thickness of finishing allowance was designed and optimized on the premise of ensuring the thin-wall stiffness of the blade, so as to realize the design of Ritz non-uniform allowance. Then, finishing machining was conducted to achieve precise parts. A blade deformation model was established to evaluate surface error with cutting force moving and changing. Finite element analysis and experimental validation in ball-end milling of a blade were conducted. FEA results and experimental results showed dimensional errors have been reduced up to 50%. Further surface tests demonstrated that the mean surface roughness reduced from 7.88 μm to 0.815 μm. And the residual surface stresses of the SLM samples changed after semi-finishing machining due to the residual stress relaxation and redistribution. The results demonstrated that the proposed method enhanced the surface quality of blade fabricated by SLM.

Geometric dissimilarity between the thickness profile of the entry strip and the deformed roll gap is the main cause of flatness defects. However, the combination of the crown ratio and the lateral metal flow complicates the flatness defect mode, making it difficult to predict. A variety of rolled flatness defects may result, generally occurring as center waviness, edge waviness, M-mode waviness, and W-mode waviness. The effect of lateral metal flow on the flatness has rarely been considered or quantified in the traditional flatness model. To address this deficiency, an original mathematical model is proposed for computing the rolled flatness defects while accounting for lateral metal flow during the rolling process. The proposed analytical model was employed to compute the flatness deviations with and without lateral metal flow, and the flatness calculated results were compared with the numerical solutions provided by a three-dimensional finite element model. The influence of the lateral metal flow on the strip flatness distribution was clearly identified and explained. Finally, the effects of the reduction rate, entry thickness, and exit crown ratio on the flatness deviation and lateral metal flow are described and discussed.

The corrugated rolling is a new rolling technology to obtain the composite plate. Compared with the flat rolling, the corrugated rolling can promote the plastic deformation of hard metal effectively and gain a composite plate with superior mechanical properties. In this paper, the finite element analysis of the copper/aluminum composite plate in corrugated rolling process was carried out. The correctness of the model was verified by experiment. The distributions of rolling normal stress, shear stress, equivalent strain and cross shear zone in corrugated rolling were obtained, and the differences between these from flat rolling were contrasted. Cross shear zone and shear stress in corrugated rolling are larger than flat rolling, which is beneficial to metal composite.

A chloride process is especially prone to leakage incidents via vaporizer rupture and pipeline perforation, both of which are usually caused by corrosion. Rupture accidents may not occur frequently but nevertheless can results in explosions, poisoning and other severe consequences. The main factors affecting the corrosion process are the chloride ion concentration and the environmental temperature. In order to study the probability of rupture accidents, this paper first presents experimental research on the corrosion performance of liquid chlorine vaporizers and pipelines made with the steel Q345 and 20G, respectively. Different chloride ion concentrations (1–20 g/L) and environmental temperatures (30–90 °C) were considered in the corrosion experiment. The experiment lasted for 42 days, and the corrosion rate was calculated using weight loss technique. The experimental results show that 20G steel suffers more serious corrosion than Q345 steel and the degree of corrosion is determined by different factors working together. Among these experimental data, the corrosivity data related to 20G steel at the corrosion environment of low temperature with low concentration (30 °C, 1 g/L), as well as at high temperature with high concentration (80 °C, 20 g/L) were selected to establish the corrosion weight loss prediction model, based on which the accumulated wall thickness reduction was further calculated. Finally, a probability prediction model for the corrosive state was established based on Markov chains. Using the dynamic prediction method proposed in this work, it is capable to determine the corrosion situation of the chloride process through predicting the rupture probability before the coming into service of process equipment. Also, these prediction results can provide some guidance for the maintenance and help to reduce the risk of rupture accidents caused by corrosion in a chloride process.

A unified model was developed from leaked high-pressure natural gas (up to 6.55 MPa) and a procedure outlined in IEEE Standard 738–2012 for transmission line conductor temperature. A real-scale case was presented to show the thermal effects of a large-scale jet fire on the nearby transmission line by setting their distances from 200 to 500 m. The predicted total flame height and damage radius correspond to the reported results with appropriate correction of input parameters. Transmission lines with higher load currents and shorter distances to the jet fire induce higher temperature rises in line conductors. Reducing the current load of transmission line needs to integrate both factors of thermal failure of transmission line and economy of power system.

This study aims to develop a complete methodology for assessing flammability hazards of typical fuels (ie, transformer oil, hydraulic oil, gear oil, and lubricating grease) used in a wind turbine nacelle by combining different experimental techniques such as thermogravimetric analysis and cone calorimetry. Pyrolysis properties (onset temperature, temperature of maximum mass loss rate, and mass residue) and reaction‐to‐fire properties (ignition time, heat release rate, mass loss rate, and smoke release rate) were determined and used for a preliminary assessment of thermal stability and flammability hazards. Additional indices, for ignition and thermal behavior (effective heat of combustion, average smoke yield, and smoke point height, heat release capacity, fire hazard parameter, and smoke parameter, were calculated to provide a more advanced assessment of the hazards in a wind turbine. Results show that pyrolysis of transformer oil, lubricating grease, hydraulic oil, and gear oil occur in the range of 150°C to 550°C. Lubricating grease and transformer oil show the higher and lower thermal stabilities with maximum pyrolysis rate temperatures of 471°C and 282°C, respectively. The measured relation between ignition time and radiant heat flux agrees well with Janssens method (a power of 0.55). The aforementioned indices appear to provide a reasonable prediction of performance under real fire conditions according to a full‐scale fire test documented by Declercq and Van Schevensteen. The results of the study indicate that transformer oil is the easiest to ignite while lubricating grease is the most difficult to ignite but also has the highest smoke production rate; that transformer oil has the highest heat release rate while gear oil has the lowest; and that the fire hazard parameter is the highest for transformer oil and the smoke parameter is the highest for lubricating grease. The potential of this type of work to design safer wind turbines under performance‐based approaches is clearly clarified.

By thermogravimetric (TG) experiments under 5 oxygen concentrations of 21.0, 40.0, 50.0, 60.0, 80.0% and 5 heating rates of 20.0, 30.0, 40.0, 50.0, 60.0 ℃/min, the combustion characteristics of jet coal and influences of oxygen concentrations and heating rates on them were investigated. Results show that the pyrolysis processes of jet coals consist of 3 segments of water evaporation, structure oxidation and mass-gaining, self-ignition and induced combustion and carbonization that lie in temperature ranges of 65.0~150.0 ℃, 150.0~290.0 ℃ and 290.0~650.0 ℃, respectively. Huainan jet coal samples burn more easily as universal ignition index increases. At constant heating rate, self-ignition temperature tends to decrease by 10.1~19.4 % with increasing oxygen concentration from 21.0 % to 80.0 %. However, the variation trend of oxidation process includes a slight rise when variation trend begins to fall. At constant oxygen concentration, the self-ignition temperature transformes into high temperature direction and lead to thermal lag effect. Values of Coal-oxidation time at various oxygen concentration levels decreased by 63.1~65.8 % at heating rates from 20.0 to 60.0 ℃/min. Accordingly, the coal-oxidation process is accelerated. A new index (R S ) named coal-oxidation difficulty level index to evaluate the lag effect of coal-oxidation process was proposed. Fitting results of three dimensionless parameters confirmed that the risk of spontaneous combustion determined by the coal-oxidation process still remains growing up although self-ignition temperature produces thermal lags with increasing heating rates.

By using sol-gel process, hybrid sols can be prepared and three dimensional nanoscale or nano-micro networks can be designed and formed onto bulk materials of diverse substrates (such as fabric and wood). Series of pure, composite and hybrid sols like SiO2, SiO2-KH560, SiO2-KH560-MA (Melamine), SiO2-KH560-BB (Boric Acid and Borax) and SiO2-KH560-TPP (Triphenyl Phosphate) including both nano-sols and traditional flame retardant components were prepared and used to finish cotton, polyester and polyester-cotton fabrics, particle size distributions and pH values of as-prepared sols were inspected. Limiting Oxygen Index (LOI), Thermogravimetry Analysis (TGA) and Fourier Transform Infrared Spectroscopy (FTIR) experiments were conducted to determine flame retardancy, characterize pyrolysis properties and identify microstructural functional groups on the surfaces of sols-finished fabrics. Effectiveness, synergistic effects and function mechanisms of organically modified hybrid sols and flame retardants were explored. Results show that LOI values are all improved after modifications of cotton, polyester and polyester-cotton fabric, coverage of main pyrolysis stage have been extended to various degrees, and amounts of residual char increase exponentially. The flame retardant effects of cotton and polyester-cotton fabrics treated with SiO2-KH560-BB is most obvious. It shows that the flame retardant hybrid sols affect the pyrolysis courses and heat resistance capacities of fabrics have been improved. It is speculated the sols form coatings on surface of fabrics and inhibit further oxidation, decomposition, and melt dripping, prolong the main pyrolysis process, prevent the fabric further oxidation and decomposition, increase the char yield, improve the thermal stability of polyester fabric. For A3, a broad peak between 650~750cm-1 is seen, indicating that a large number of OH groups exist, and absorption peaks at 1295 cm-1 reveals the presence of Si-C-O groups. The OH groups, boric acid and borax can both strengthen dehydration and char formation capacities by developing thin films surrounding fibers. Superb synergistic effect happens.

Corrugated rolling technology is a new method to produce metal laminated composite. Compared with flat rolling, the corrugated rolling can effectively promote the deformation of hard-deformed metal, refine metal grains and obtain laminated composite with superior mechanical properties. A three-dimensional simulation model of Cu/Al laminated composite produced by the corrugated rolling process is set up through finite element method, and its accuracy is verified by experiments. The friction stress of contact surfaces between the plate and the roll are obtained to analyze the dynamic multiple neutral points and the distributions of the cross shear zones at different moments. Corrugated rolling greatly increases the friction stress values and cross shear zone areas without the changing of rolling mill equipment capacity, and the microstructure characteristics in different position of deformation zone reflect the fact. The stress state of whole rolling process is further analyzed by stress triaxiality and Lode parameter plane in which the cross shear zones are close to considerable shear state, and greater shear deformation makes the rupture of the oxide layer and hardened layer at the bonding interface easier. Therefore, the corrugated rolling can coordinate the deformation of metals with different resistances and then improve the composite quality.

Processing schedules for grain boundary engineering involving different types of cold deformation (tension, compression, and rolling) and annealing were designed and carried out for 18Mn18Cr0.6N high nitrogen austenitic stainless steel. The grain boundary characteristic distribution was obtained and characterized by electron backscatter diffraction (EBSD) analysis. The corrosion resistance of the specimens with different grain boundary characteristic distribution was examined by using potentiodynamic polarization test. The corrosion behavior of different types of boundaries after sensitization was also studied. The fraction of low-Σ boundaries decreased with increasing strain, and it was insensitive to the type of cold deformation when the engineering strain was lower than 20%. At the strain of 30%, the largest and smallest fractions of low-Σ boundaries were achieved in cold-tensioned and rolled specimens, respectively. The fraction of low-Σ boundaries increased exponentially with the increase of grain size. The proportion of low-angle grain boundaries increased with decreasing grain size. Increasing the fraction of low-Σ boundaries could improve the pitting corrosion resistance for the steels with the same grain size. After sensitization, the relative corrosion resistances of low-angle grain boundaries, Σ3 boundaries, and Σ9 boundaries were 100%, 95%, and 25%, respectively, while Σ27 boundaries, other low-Σ boundaries and random high-angle grain boundaries had no resistance to corrosion.

The flashover performance of insulators is significantly affected by the degrees and ways of wetting the pollution layer. However, there have only been a few reports on the wetting condition and its effects on the flashover characteristics of pollution on insulators to date. In this paper, a phase-angle difference-based method is proposed to test the wetting conditions of the pollution layer on insulators. A corresponding measuring device is also developed. The wetting process of the pollution layer on aerodynamic-type glass insulators is studied in an artificial climate chamber using the developed device. The related flashover performance is studied via the even-rising voltage method. Test results show that the phase-angle difference (PAD) curve accurately reflects the entire wetting process of the pollution layer from the initial stage, through the saturated stage to the oversaturated and washing away stages. Over the wetting process, the PAD curve initially drops sharply, and then remains stable for a few minutes before eventually rising slowly to the initial value. The PAD curve has its lowest value when the pollution layer is wetted to saturation, which occurs after approximately 5 min in our experiments. The flashover voltage characteristics of insulators are also significantly affected by the wetting conditions of the pollution layer. The flashover voltage in the saturated stage is shown to be lower than that in the other stages. Therefore, to improve the accuracy of the artificial pollution tests, quantitative methods (including PAD) should be used to obtain the exact time of wetting to saturation.

A novel hybrid BiVO 4 –SiO 2 composites with mesoporous composite structure were synthesized by hydrothermal calcination method. The as-prepared BiVO 4 /SiO 2 hybrid material was characterized by scanning electron microscopy, X-ray photoelectron spectroscopy, X-ray diffraction, UV–vis diffuse reflectance spectroscopy and BET measurements, respectively. Its photocatalytic activity was evaluated by the performance for decomposing C.I. Reactive Blue 19 in aqueous solution under visible light irradiation, and photocatalytic efficiency was effectively improved compared to the pure semiconductor materials.

The treatment of organic-rich sludge is significant in geotechnical engineering, which contributes to the resource utilization of sludge and environmental protection. In this paper, several solidifying materials, namely cement, quick lime, potassium ferrate, and super absorbent polymers are selected to treat sludge. Experimental results show that the unconfined compressive strength of treated soil samples is significantly enhanced, and the heavy metal ions concentration measured from the exudation fluid of soil samples is reduced by treatments. Furthermore, the treatment mechanism is investigated by using X-ray diffraction and Scanning Electron Microscopy at the micro scale. The mixing of solidifying materials into sludge leads to the formation of cementitious compounds and the flocculation of clay particles.

The micro-tubes with inner diameter 0.8 mm are arrayed to serve as the heat transfer unit in the mini heat exchanger we developed and the investigation on the heat transfer capability of the array of micro-tubes are carried out experimentally. To perform the experiments conveniently and economically, six plates with nozzles and sealing grooves are used to construct a hexahedral shell of the mini heat exchanger based on bolted connections, and the units are easily to be disassembled so that the heat transfer array can be replaced if necessary. The arrangement of micro-tubes is similar to that in the conventional micro shell-and-tube heat exchanger. The experiments are carried out under atmospheric pressure condition, so the inlet temperatures and mass flow rates for both shell-side and tube-side fluids can be adjusted. The heat transfer coefficient is calculated to evaluate the heat transfer efficiency of the array of micro-tubes, and the influences of some parameters, such as tube inner diameter, tube spacing distance, inlet temperature difference, inlet mass flow rates, etc., on the heat transfer coefficient are investigated. By comparing the heat transfer coefficient of the mini heat exchanger with that of the conventional shell-and-tube heat exchanger, it is revealed that the heat transfer enhancement is realized by using the array of micro-tubes. The enhancement profits from the large heat transfer area per unit volume and small thermal resistance in boundary layer.

Yttria-stabled zirconia (YSZ) electrolyte film was prepared on NiO/YSZ anode substrate by a slurry dip-coating technique for intermediate temperature solid oxide fuel cells (IT-SOFCs). The pre-sintering temperature of the anode substrate is crucial to the densification of the electrolyte films, and an optimal temperature of 1000 oC was determined. SEM tests indicated that homogeneous and dense electrolyte film with a thickness of 24 μm could be obtained by twice dip-coating, with good adhesion to the anode substrate. A cell assembled with the prepared YSZ electrolyte films presents an open circuit voltage (OCV) of 1.14 V and a power density of 0.50 W·cm-2 operated at 800 oC. Electrochemical impedance spectra analysis shows that it is the polarization resistance of the electrode, rather than Ohmic resistance of the electrolyte film, that dominates the cell performances. The prepared electrolyte film has an electric conductivity of 0.0098 S ·cm-1 at 800 oC. The slurry dip-coating technique was also applied to fabricate YSZ films for large size (55 mm × 55 mm) IT-SOFCs, and the maximum power density is 146 mW·cm-2. This result indicates that the slurry dip-coating technique for preparation of YSZ electrolyte films has potential application in fabricating SOFC stacks.

A new efficient and stable visible light driven photocatalyst, carbon quantum dots (CQDs)-surface modified P25 nanocomposite, was successfully prepared by chemical adsorption of CQDs onto the surface of TiO2 nanoparticles and then used for water treatment. The photocatalyst was characterized by X-ray powder diffraction, transmission electron microscopy, X-ray photoelectron spectroscopy, infrared spectrometry, thermogravimetric analysis, and UV-vis spectrometry. After the modification of titanium dioxide with carbon quantum dots, the UV-vis wavelength response range extended from 390 nm to 420 nm by accelerating the photogenerated electron transfer from carbon quantum dots to titanium dioxide, and the band gap decreased from 3.08 eV to 2.87 eV. In addition, a blue shift of binding energy was observed, namely, 0.6 eV for Ti2p1/2 and 0.7 eV for Ti2p3/2. Furthermore, compared with pure titanium dioxide, after irradiating for 2.5 h, the photodegradation ratio of acid violet 43 and p-nitrophenol have been enhanced from 60% to 93% and from 89% to 96%, respectively. Moreover, after five cycle times, the stability of the photocatalyst has been maintained due to the strong interaction between carbon quantum dots and titanium dioxide.

Bismuth vanadate-coated cotton fabric was synthesized by a chemical bath deposition method at low temperature (≤100℃) and characterized by using scanning electron microscopy, X-ray photoelectron spectroscopy, X-ray diffraction and UV-V is diffuse reflectance spectroscopy. Its photocatalytic activities were evaluated by decomposition of C.I. reactive blue 19 in aqueous solution under visible light irradiation. The as-prepared composite possesses excellent photocatalytic activity for the degradation of liquid contamination especially in static system due to its large specific surface area. The reduction of total organic carbon (about 48.0% after 4 h of irradiation) showed that the mineralization of C.I. Reactive Blue 19 over the bismuth vanadate-coated cotton fabric is realizable. Moreover, the preparation of the composites is convenient for potential practical application. The formation mechanism of bismuth vanadate on the fabric was also discussed preliminarily.

Gas explosion in connected vessels usually leads to high pressure and high rate of pressure increase which the vessels and pipes can not tolerate. Severe human casualties and property losses may occur due to the variation characteristics of gas explosion pressure in connected vessels. To determine gas explosion strength, an experimental testing system for methane and air mixture explosion in a single vessel, in a single vessel connected a pipe and in connected vessels has been set up. The experiment apparatus consisted of two spherical vessels of 350 mm and 600 mm in diameter, three connecting pipes of 89 mm in diameter and 6 m in length. First, the results of gas explosion pressure in a single vessel and connected vessels were compared and analyzed. And then the development of gas explosion, its changing characteristics and relevant influencing factors were analyzed. When gas explosion occurs in a single vessel, the maximum explosion pressure and pressure growth rate with ignition at the center of a spherical vessel are higher than those with ignition on the inner-wall of the vessel. In conclusion, besides ignition source on the inner wall, the ignition source at the center of the vessels must be avoided to reduce the damage level. When the gas mixture is ignited in the large vessel, the maximum explosion pressure and explosion pressure rising rate in the small vessel raise. And the maximum explosion pressure and pressure rising rate in connected vessels are higher than those in the single containment vessel. So whenever possible, some isolation techniques, such as fast-acting valves, rotary valves, etc., might be applied to reduce explosion strength in the integrated system. However, when the gas mixture is ignited in the small vessel, the maximum explosion pressures in the large vessel and in the small vessel both decrease. Moreover, the explosion pressure is lower than that in the single vessel. When gas explosion happens in a single vessel connected to a pipe, the maximum explosion pressure occurs at the end of the pipe if the gas mixture is ignited in the spherical vessel. Therefore, installing a pipe into the system can reduce the maximum explosion pressure, but it also causes the explosion pressure growth rate to increase.

Dry etching has now become one of the key processes of high ratio of depth to width microstructure and fine patterning. This paper presents a new dry etching technology - multilayer reactive ion etching technology (MRIE). By taking full advantage of the spatial layout of the chamber, arranging multi-layer electrodes and transporting the discharged gas by a layered air supply device, the function of simultaneous etching in every reaction chamber (layer) is realized. This method can significantly enhance the productivity. Taking the photoresist etching by MRIE as an example, the law and mechanism influencing the etching rate and uniformity were analyzed for different conditions. The result shows that when plate distance is 50/55/60 mm (from bottom to top), and vacuum degree, ratio of O2 to Ar, RF source power, and continuous etching time are respectively 40 Pa, 1/2, 600 W, and 20 min, the optimal process is achieved. The average etching rate and uniformity are 143.93 ?/min and 9.8%, respectively.

Polymeric nanomaterials emerge as key building blocks for engineering materials in a variety of applications. In particular, the high modulus polymeric nanofibers are suitable to prepare flexible yet strong membrane separators to prevent the growth and penetration of lithium dendrites for safe and reliable high energy lithium metal-based batteries. High ionic conductance, scalability, and low cost are other required attributes of the separator important for practical implementations. Available materials so far are difficult to comply with such stringent criteria. Here, we demonstrate a high-yield exfoliation of ultrastrong poly(p-phenylene benzobisoxazole) nanofibers from the Zylon microfibers. A highly scalable blade casting process is used to assemble these nanofibers into nanoporous membranes. These membranes possess ultimate strengths of 525 MPa, Young's moduli of 20 GPa, thermal stability up to 600 °C, and impressively low ionic resistance, enabling their use as dendrite-suppressing membrane separators in electrochemical cells. With such high-performance separators, reliable lithium-metal based batteries operated at 150 °C are also demonstrated. Those polyoxyzole nanofibers would enrich the existing library of strong nanomaterials and serve as a promising material for large-scale and cost-effective safe energy storage.

A Nb-containing 316LN stainless steel was compressed in the temperature range 900–1200 °C and strain rate range 0.01–10 s−1. The mechanical behavior has been characterized using stress–strain curve analysis, kinetic analysis, processing maps, etc. The microstructural evolution was observed and the mechanism of flow instability was discussed. It was found that the work hardening rate and flow stress decreased with increasing deformation temperature and decreasing strain rate. On the contrary, the efficiency of power dissipation increased with them; Flow instability was manifested as cracking and flow localization; The hot deformation equation and the relationships between deformation condition and dynamic recrystallization grain size and fraction were obtained; For Nb-containing 316LN stainless steel, the favorite nucleation sites for dynamic recrystallization are in sequence of triple point, grain boundary, twin boundary and intragranular deformation band; The suggested processing window is given.

An 8% Cr cold roller steel was compressed in the temperature range 900–1200 °C and strain rate range 0.01–10 s−1. The mechanical behavior has been characterized using stress–strain curve analysis, kinetic analysis, processing maps, etc. Metallographic investigation was performed to evaluate the microstructure evolution and the mechanism of flow instability. It was found that the work hardening rate and flow stress decreased with increasing deformation temperature and decreasing strain rate in 8% Cr steel; the efficiency of power dissipation decreased with increasing Z value; flow instability was observed at higher Z-value conditions and manifested as flow localization near the grain boundary. The hot deformation equation and the dependences of critical stress for dynamic recrystallization and dynamic recrystallization grain size on Z value were obtained. The suggested processing window is in the temperature range 1050–1200 °C and strain rate range 0.1–1 s−1 in the hot processing of 8% Cr steel.

Filters for soft-x-ray are mostly self-supported metal thin films.Under experimental circumstance,while long exposure to the air of the self-supported metal thin film,impurity atoms will enter into self-supported thin film,which will result in decline of self-supported thin film′s optics performance.Zr filters have high transmittance at band from 5 nm to 20 nm because of its low mass absorption coefficient and density.After vapor depositing NaCl film on cleaned float glass as a release agent,Zr film was sputtered on NaCl film.Self-supported Zr film wass prepared after NaCl film being dissolved in deionized water.To prevent surface oxidizing and impurity atoms from the air entering Zr film in experimental environment,C or Si film with 10 nanometer thickness was sputtered on both Zr film sides for separating Zr from the air.Measurement result of C/Zr/C and Si/Zr/Si film shows that C or Si film has little influence on self-supported Zr film performance.

Multiporous CuCo2O4 microspheres have been synthesized via a facile solvothermal method and used as bifunctional electrocatalysts for rechargeable Li-O2 batteries. The Li-O2 battery utilizing CuCo2O4 shows a higher specific capacity of 5607 mAh g-1 than that with pure Ketjen black (KB). Moreover, the Cu-Co2O4-based electrode enables much enhanced cyclability than that of the carbon-only cathode. Such excellent catalytic performance of CuCo2O4 could be associated with its inherent catalytic activity and multi-porous microspheres structure.

A novel two-step process was developed to synthesize and deposit SiO 2 /TiO 2 multilayer films onto the cotton fibers. In the first step, SiO 2 particles on cotton fiber surface were synthesized via tetraethoxysilane hydrolysis in the presence of cotton fibers, in order to protect the fibers against photo-catalytic decomposition by TiO 2 nanoparticles. In the second step, the growth of TiO 2 nanoparticles into the modified cotton fiber surface was carried out via a sol–gel method at the temperature as low as 100 °C. The as-obtained SiO 2 /TiO 2 multilayer films coated on cotton fibers were characterized by scanning electron microscopy, X-ray photoelectron spectroscopy, atomic force microscopy and X-ray diffraction, respectively.