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Volatile organic compounds (VOCs) are the major air pollutants inside vehicles. In this research, a highly sensitive gas sensor was developed based on an excellent sensing material and explored for VOCs sensing application. The X-ray diffraction and scanning electron microscopy were performed to evaluate the detailed structural features of sensing material. From the gas-sensing property tests to the three representative VOCs vapors, containing xylene, toluene and formaldehyde, the gas sensor fabricated from the exceptional sensing material significantly responses to the three VOCs vapors. In particular, the xylene response of the sensor is slightly larger than the other two gas response. Thus, the fabricated sensor could be a promising application for VOCs detection inside vehicles.

Human activities in cold climates are more and more frequent. But, an efficient strategy to maintain the human body temperature is still a challenging work. In this paper, we propose a photothermal...

An approach to simulate the constitutive model of a unidirectionally SiC fiber-reinforced titanium matrix composite during spectrum loading was developed in this paper. Based on the assumption that there is a microcrack in the matrix and the maximum shear stress criterion, the debonding length and the distribution of interfacial slip zone under spectrum loading were derived. The stress at a loading point was divided into four stages including crack opening section, positive slip zone, reverse slip zone, and bond zone. Based on the partial crack shear-lag model, the stress of fiber and matrix in the four stages was derived, and the constitutive model of the composite under spectrum loading was established. At last, the effects of different damages on the constitutive model and interfacial debonding zone of a unidirectionally SiC fiber-reinforced titanium matrix composite were investigated.

A millimeter-wave dual-band shared-aperture high-efficiency reflectarray antenna (RA) based on the structure-reuse technique is proposed in this letter, which consists of two sets of elements with full 360° phase compensation ranges. The oblique dipole element excited by the substrate integrated waveguide (SIW) is employed for the lower frequency band. The equivalent metallic waveguide element with the unchanged periodic grid and transverse size is selected for the higher frequency band. To make full use of the radiating aperture and, then, improve the aperture efficiency of the dual-band RA, the SIW-fed dipole cells are used to replace a pair of symmetry walls of the metallic waveguide cell in the x -polarization direction. The measured gains of the proposed RA are 28.7 dBi with the aperture efficiency of 43.59% at 18 GHz and 35.8 dBi with the efficiency of 50.12% at 38 GHz. The simulated and measured results successfully validate the effectiveness of the proposed method in the design of a millimeter-wave dual-band shared-aperture RA.

Preventing the penetration of water while allowing it to pass through quickly is the key to achieving waterproof and breathable membranes; it opens up new possibilities for applications in all area...

The cryogenic performance of multinanoscale CMOS transistors with a standard 55-nm Si-bulk technology is systematically investigated by dc measurements. In contrast to 300 K, the cryogenic drain saturation current ( ${I}_{\text {dsat}}$ ) gain significantly enhances from 54% to 167% with the increasing channel length and has a relatively weak response to width change. In addition, the degraded subthreshold swing (SS) due to the short channel effect is alleviated at lower temperatures. The merits of a typical nMOS transistor ( ${W}/{L} = 0.6~\mu \text{m}$ /60 nm) worked at 4.2 K are associated with an improved ${I}_{\text {dsat}}$ (~1.3 times), decreased drain leakage current with three orders of magnitude, and 2/3 reduced SS. However, the cryogenic ${I}_{\text {dsat}}$ tends to saturate below 10 K and the threshold voltage increases, as well as barrier lowering induced by drain voltage, starts to deteriorate. The detailed analyses on these MOSFET (deep) cryogenic characteristics are implemented based on the comprehensive semiconductor physics images, including energy band change, temperature/geometry-dependent scattering, band-to-band tunneling process, and depletion width influence. Our findings will be beneficial for the community to design ultralow temperature-integrated circuits.

Smaller fibers are welcome in many applications due to larger surface area, but there is a threshold for smallest fibers for a fixed spinning system. In order to further improve surface area, hierarchical structure is considered in this paper using electrospinning. A bi-solvent system is used in our experiment for fast solvent evaporation. Unsmooth nanofibers are obtained, and the formation mechanism is elucidated.

Designing defect-engineered semiconductor heterojunctions can effectively promote the charge carrier separation. Herein, novel ceria (CeO2) quantum dots (QDs) decorated sulfur-doped carbon nitride nanotubes (SCN NTs) were synthesized via a thermal polycondensation coupled in situ deposition-precipitation method without use of template or surfactant. The structure and morphology studies indicate that ultrafine CeO2 QDs are well distributed inside and outside of SCN NTs offering highly dispersed active sites and a large contact interface between two components. This leads to the promoted formation of rich Ce3+ ion and oxygen vacancies as confirmed by XPS. The photocatalytic performance can be facilely modulated by the content of CeO2 QDs introduced in SCN matrix while bare CeO2 does not show activity of hydrogen production. The optimal catalyst with 10% of CeO2 loading yields a hydrogen evolution rate of 2923.8 μmol h−1 g−1 under visible light, remarkably higher than that of bare SCN and their physical mixtures. Further studies reveal that the abundant surface defects and the created 0D/1D junctions play a critical role in improving the separation and transfer of charge carriers, leading to superior solar hydrogen production and good stability.

Based on shear strength calculation, this paper established an accurate method to measure the ice adhesion strength on any solid surface in an environment chamber by using self-made experimental equipment. The inherent characteristics of material and external environment which have strong influence on ice adhesion strength were investigated. The mechanism of ice adhesion was interpreted by studying the adhesion strength of ice layer with different surface wettability. The smooth steel substrate without any treatment and superhydrophobic surface samples were selected to study the relationship between ice adhesion strength and surface temperature. Meanwhile, the ice peak adhesion strength of the surface after freezing for 20–360 min under different low temperatures was analyzed. The results showed that the equipment provides a scientific and reasonable approach for the researchers to characterize the anti-icing performance of surfaces with different wettability.

Non-enzymatic and reagentless electrochemical sensors for convenient and sensitive detection of glucose are highly desirable for prevention, diagnosis and treatment of diabetes owing to their unique merits of simplicity and easy operation. Facile fabrication of a three-dimensional (3D) sensing interface with non-enzymatic recognition groups and an immobilized electrochemical probe remains challenge. Herein, a novel non-enzymatic electrochemical sensor was developed for the sensitive and reagentless detection of glucose by loading functional nanostructure on 3D graphene. Monolithic and macroporous 3D graphene (3DG) foam grown by chemical vapor deposition (CVD) served as the electrode scaffold. Prussian blue (PB) and gold nanoparticles (AuNPs) were first co-electrodeposited on 3DG (3DG/PB-AuNPs) as immobilized signal indicator and electron conductor. After a polydopamine (PDA) layer was introduced on 3DG/PB-AuNPs via facile self-polymerization of dopamine to stabilize internal PB probes and offer chemical reducibility, the second layer of AuNPs was in situ formed to assemble the recognition ligand, mercaptobenzoboric acid (MPBA). Owing to the high stability of PB and good affinity between MPBA and glucose, the non-enzymatic sensor was able to be used in reagentless detection of glucose with high selectivity, wide linear range (5 μM–65 μM) and low detection limit (1.5 μM). Furthermore, the sensor was used for the detection of glucose level in human serum samples.

The insights into the transport mechanism of Pu in granite fractures are indispensable for a reliable safety-assessment of radioactive waste disposal sites. In this work, the study of transport behavior of Pu in a rough single fracture has been performed under different pH conditions. The results indicated that under strong acidic condition the sorption of Pu dominated by ion-exchange reaction is quite weak, reversible and not be affected by the change of flow rates, while under neutral condition the majority of Pu can be adsorbed onto granite surface, controlled by surface-complex reaction between Pu(OH)4(aq) and fracture surface hydroxyl groups.

Developing high-entropy alloy (HEA) coatings with preferable properties for severe environments is a promising and cost-efficient way. In this work, an original HEA CoCrFeNiCu1-xMox coatings were designed on-demand and successfully prepared on duplex stainless steel (DSS) through coaxial direct laser deposition technique. The first-principles calculation based on the density functional theory was employed to calculate the characteristics of materials. The results showed that the uniformly distributed Cu could stabilize the face-centered cubic phase structure, hinder the transfer of point defects, and activate the cathode. The synergistic effect of Mo and other HEA elements was beneficial in reducing the point defect density of the passive film, and an appropriate amount of Mo was contributed to grain refinement, solid solution strengthening, and precipitation strengthening of the coating. When the ratio of Cu to Mo is 1:3, a small number of nanoscales second sigma phase (Fe-Cr-Mo) appeared between ordered and disordered, which balanced the coating's corrosion and slurry erosion wear performances. Compared with DSS, the corrosion current density of CoCrFeNiCu0.25Mo0.75 coating was reduced by nearly an order of magnitude, the impedance was increased by 2.5 times, and the erosion wear resistance was increased by 4 to 5 times.

The rational designs of particle size, morphology and surface states of the Au nanoparticles(AuNPs) are crucial for Au nanocatalyst. We herein report a method to synthesize the silica microspheres supported AuNPs(ca. 1 nm) and their application in controlling the reaction conversion and selectivity in styrene epoxidation. Surfactant-free AuNPs deposited on silica microspheres were in situ fabricated with aid of the Ag nanoparticles (AgNPs) as sacrificial template by galvanic replacement reaction, leading to AuNPs/SiO2 catalyst directly without any post-treatment to expose crystal facets. A high conversion of 46.7% and selectivity of 91.7% to styrene oxide was achieved with H2O2 as oxidant in ethanol. The solid catalyst could be reused at least 10 reaction cycles without significant decrease in activity and selectivity. This study not only supplies an active, recoverable catalyst for styrene oxidation with green oxidant and solvent, but also demonstrates that the silica microspheres functionalized with thiol groups have a superior ability in stabilizing noble metal nanoparticles even without any surfactant.

The adhesion strength between coating and substrate is the critical factor to attain high wear resistance and other properties of the coating. In this study, a novel method for evaluating the adhesion strength is employed to measure the shear strength of the interface between High Velocity Oxygen Fuel (HVOF) spraying WC-Co coating and Q345C steel substrate. The results showed that the crack initiated at the coating surface, then propagated towards the substrate, and finally stopped at the interface. Cracks perpendicular to strain direction was formed in prior. Cross-linked cracks parallel to the axis direction were found to form after the saturation of the crack formation in the coating perpendicular to strain direction. The average shear strength varied from 132.6 to 200.3 MPa. The maximum shear strength obtained could be as high as 354.6 MPa and the minimum shear strength was 74.9 MPa.

Herein we investigate the effect of C2H2 inoculation on the grain refinement of AM60B magnesium alloy. The sample inoculated by CO2 was also prepared for comparison. Corresponding microstructures and mechanical properties of inoculated alloys at different holding times were analysed to explore the fading behaviours of the inoculants. The grain size of AM60B alloy with C2H2 inoculation decreased from the initial 412 μm to a minimum 101 μm after holding for 30 min, while that inoculated with CO2 reached the minimum of 92 μm after only 10 min A model was proposed to explain the lag of the optimum refinement point for C2H2 inoculated alloy. The heterogeneous nucleation of Al4C3 was considered the main reason for the grain refinement. However, the samples treated with CO2 exhibited poorer tensile strength than those treated with C2H2 due to the formation of MgO and MgAl2O4. With increasing holding time, the size of Al4C3 particles became increased and gradually transformed to the Al-C-Mn phases, resulting in the increased grain size. During the holding procedure, the Al elements sank down in the melt, leading to a slight increase in plasticity after holding for 2 h.

Boron nitride nanotubes (BNNTs) were treated as brittle materials and could be used to enhance the composite mechanical properties. Many approaches were used to verify the theoretical prediction experimentally, but how to in situ real-time characterize nanomechanical properties of BNNTs was still interested to the researchers. An in situ transmission electron microscopy (TEM) equipped with a force transducer holder had been used to study the structure evolution behavior of BNNTs with axial compression. Real-time video and the force transducer had been used synchronously to record the whole force loading process where the mechanical deformation of BNNT began, buckled and ended with fracture. An individual ultrathin BNNT was employed to conduct the loading test. The results showed that the elastic deformation happened on the BNNT. Young’s modulus ∼1.05-1.37 Tpa and elasticity coefficient ∼198.7-255.9 N/m of BNNT were calculated by Euler formula and Hooker’s law, respectively.

The brake discs of high-speed trains undergo severe abrasion on snowy days, which damages the safety of railway transportation. In the present paper, the mechanism leadinig to severe abrasion failure of brake discs in snowy days was determined. The microstructure and morphology of the scrap, damaged brake discs and pads were examined. The chemical composition of scrap surfaces was investigated. The ice wrapping the pads was collected and the inclusion in the ice was inspected. Moreover, camera surveillance was used to record the braking process on snowy days. Based on the results, a model for illustrating the severe abrasion process of brake discs was established. The hard particles in the ice wrapping brake pads scratched the brake disc and generated some swarf in the beginning. The swarf stacked and worked as abrasive material to gouge the brake discs, causing the severe abrasion failure finally. To demonstrate the model, reduced scale dynamo tests were carried out to simulate the severe abrasion according to speculation of the model, and similar results consistent with the actual situation were obtained.

著者人数: 11名, Accepted: 2019-02-08, 資料番号: SA1180383000

In this work, nitrogen doped clews-like carbon materials were successfully fabricated through hydrothermal polymerization method, followed by post treatment that integrated the carbonization, activation and post-nitrogen doping into one process. This preparation method can form particular hierarchical porous structure without using any sacrificial templates. The experimental results show that the nitrogen doped clews-like hierarchical porous carbon materials possess a relatively high specific surface area of 815 m2/g with the nitrogen content of 10.58 at%. The electrochemical properties show that the resulting sample delivers 258 F/g at a 0.5 A/g and excellent capacity retention of 79% at 20 A/g. After conducting 10,000 charge-discharge cycles at 10 A/g, the capacitance retention of 98.3% is achieved. These intriguing results demonstrate that the obtained nitrogen doped clews-like carbon materials will be promising electrode materials for supercapacitor and other energy storage devices.

A design strategy is presented for the development of a laser-deposited Stellite 6 coating with high ductility and low thermal fatigue crack propagation rate. The strategy involved adding titanium to modify carbide morphology, accompanied by an increase in the nickel content to stabilize the γ-Co phase in the matrix. The molar ratios of the titanium to the carbon in coatings were 0.5, 1.0, 1.5, and 2.0. The amount of nickel added to the titanium-modified coatings was 10 and 20 wt%. The net-like M23C6 eutectic carbides in the Stellite 6 coating transformed to isolated TiC particles with increasing molar ratio of titanium to carbon. Adding nickel to the coatings resulted in an increase in the stacking fault energy and the stabilization of the γ-Co phase. Accordingly, the ductility increased with increasing nickel concentration. The modified coating, named 1.0Ti20Ni, in which the molar ratio of titanium to carbon was 1.0 and the nickel concentration was 20 wt%, exhibited the highest elongation to fracture (~12%), along with a high strength (1230 MPa) in all coatings, Besides, the 1.0Ti20Ni coating revealed the lowest thermal fatigue crack propagation rate. Keywords: Stellite 6 coating, Coating design, Microstructure, Mechanical properties, Thermal fatigue crack propagation

A green process that uses the spray pyrolysis method to prepare activated alumina is proposed in this research. The effects of spray temperature, carrier gas pressure, and AlCl3 solution concentration are experimentally investigated using pure reagents. The products were characterized by X-ray diffraction (XRD), scanning electron microscope (SEM), and specific surface area (BET) analyses. The results indicate that the spray temperature is the most important factor on the conversion ratio of alumina during the spray pyrolysis process. The conversion ratio of alumina achieved over 99% at the following optimal conditions: temperature of 1000°C, pressure of 0.3 MPa, and AlCl3 solution concentration of 10 wt%. The activated alumina with 8–20 nm particle size (γ-Al2O3+α-Al2O3) was prepared using the same process, which well met the requirement of the catalyst carrier. The green utilization of high-alumina fly ash and acid recycling can be achieved by using this process.

In this work, numerical simulation methods have been applied to a 4H SiC trench-gate MOSFET structure to investigate its susceptibility to single event burnout. With SILVACO ATLAS, the high-k shielded trench-gate MOSFET and high-k trench-gate MOSFET are investigated to prove that P+ shielding region under the trench bottom could provide a leaking path of hole current and improve the device's tolerance to single-event burnout. The simulation results show that the using of P+ shielding region makes the burnout threshold voltage change from 360 V in high-k trench-gate MOSFET to 470 V in high-k shielded trench-gate MOSFET, about 30.6% improvement in the performance of SEB.

This study focused on the effect of inserting fins into metal foam on the solidification rate. To this aim, a well-designed experimental system with solid-liquid interface visualization was built. ...

Graphite-silver (AgC) composite materials are widely used in outdoor high-voltage electrical switchgear due to their combining properties of excellent conductivity and outstanding arc-suppressing performance. However, the methods for fabricating AgC composite materials still have some limitations. In this study, the cold spray technique was adopted to deposit AgC composite coatings with the optimized parameters on the copper substrate. Then, AgC coatings were annealed in the furnace and treated by laser scanning, respectively, to further improve the arc erosion resistance performance of the coatings. The results show that the phase structure and electrical resistance of AgC coatings were not influenced by the post-treatment process. Furthermore, excellent hydrophobic performance was obtained after surface laser scanning treatment. The laser scanning treatment exhibited favorable advantages in enhancing the arc erosion resistance of AgC coatings, which indicated the lowest arc erosion rate compared with the cold-sprayed and annealed coatings.

This investigation focuses on obtaining martensite stainless steel part with uniform mechanical properties along the building direction (BD) by plasma arc direct energy deposition (DED). A tailored 1Cr17Ni2B alloy powder and layer minimum temperature control process were employed. The results revealed that the tensile strengths along BD exhibited a good uniformity with a relative difference less than 1.4 % and the average ultimate tensile strength was 1382 MPa. The high microhardness along the BD also showed a good uniformity, only slightly fluctuated from 542–606 HV0.3 with a periodic length of one concave fish-scale pattern. Then the part along BD was simplified to overlapped concave fish-scale patterns. The microstructure evolution of fish-scale pattern was studied and the result showed that the concave fish-scale pattern was characterized by intragranular lath martensite and intergranular M23(C,B)6+α-Fe eutectic structure. Besides, M2(C,B) particles were distributed on intergranular α-Fe matrix. The layer minimum temperature control of 200︒C process was employed to ensure the eutectic M23(C,B)6 in a concave fish-scale pattern only partly dissolved during the deposition of the next one layer, not during the subsequent layers. It is helpful to deposite concave fish-scale patterns along the BD with similar volume fraction of eutectic M23(C,B)6 and mechanical properties. This investigation discloses a new method to deposite Fe-Cr-C-B alloy part containing intergranular carbides with uniform mechanical properties and high hardness along the BD.

(TiVCrNbSiTaBY)N high entropy alloy nitride (HEAN) coatings have been deposited onto Si (100) and cemented carbide substrates by radio frequency magnetron sputtering. The deposition is carried out at different bias voltages to study its influence on microstructure, morphology, mechanical properties and tribological behaviour of the coatings. Grazing Incidence X-Ray Diffraction (GIXRD) technique shows that all coatings exhibit single NaCl-type face-centered cubic (FCC) crystal structure, while the preferred orientation of the crystal structure is greatly affected by the bias voltages. High resolution transmission electron microscopy (TEM) reveals that the structure of the coatings is a mixture of amorphous-like phase and FCC crystal structure, which is in agreement with GIXRD data. Cross-sectional Scanning Electron Microscopy (SEM) images exhibit that the columnar structure of the coatings gradually transforms into a featureless dense structure with the increase of bias voltage. SEM and Atomic Force Microscopy reveal that the surface morphology become smoother with increasing bias voltage. The (TiVCrNbSiTaBY)N HEAN coating deposited at a specific bias voltage exhibit a high hardness of 32.2 GPa. The friction coefficient is significantly influenced by the variation of the coatings surface roughness. Tribological tests for coating deposited without and at low bias voltage show that the wear behavior of the coatings is severe abrasive wear and adhesive wear, while at high bias voltage the slight abrasive wear appears. By applying the substrate bias voltage, the (TiVCrNbSiTaBY)N coatings exhibit excellent mechanical and tribological performance, which can be a promising candidate for protective coating in cutting tools or components.

This paper analyzes the relationship between vibration characteristics of ultra-high voltage (UHV) transformer and DC bias current. The main source of UHV transformer's no-load vibration is the magneto-strictive vibration of the magnetic core. However, unlike the small power transformer, the characteristic of large inductance to small resistance of UHV transformer which can easily lead to not only a long transient process but also the calculation error due to the small DC voltage compared to the 1000 kV AC voltage. Thereby, a fast solution called series resistance and voltage compensation method (SRVCM) is utilized to shorten the transient process. By means of SRVCM, the vibration displacement, acceleration and its harmonics under different DC bias are calculated by a weak magneto-mechanical coupling model. The DC bias experiment of two identical 250MVA/500kV transformer with no load is carried out, and the calculated and measured vibration acceleration are compared.

There are many deep hole processing methods for TC4 titanium alloy, but it is a blank to drill with a mahine-clamped deep hole drill, so we have carried out some experi--mental studies. Using different spindle speed and feed in the test process of chip morphology and chip removal condition respectively and drill bit, the abrasion of guide block is analyzed using single factor method is suitable for the machine clamp type TC4 titanium alloy drilling deep hole drill in the best condition, get the best speed, the best feeding, for deep hole drill machine clamp type provides effective of TC4 titanium alloy drilling processing parameters.

In order to study the grating constant of the matte light pillar holographic materials, the X-Rite MA68 II multi-angle spectrophotometer was used to measure the spectral energies of the matte light pillar holographic materials. The reflective and diffractive spectral energies perpendicular to the direction of the light pillar and along the direction of the light pillar in the visible light range at five angles (15°, 25°, 45°, 75°, 110°) were analyzed with the grating equation. It was found that the grating constant of the matte light pillar holographic materials is in a range rather than that of the rainbow light pillar holographic materials which had fixed value, which will only cause the lightness variations significantly.

For the uneven gas–solid distribution in the process of fluidized bed ironmaking, the effect of the distributor on gas–solid homogeneity in fluidized bed was investigated by using physical simulation. Statistical analysis and spectral analysis were used to investigate the pressure fluctuations in the fluidized bed with the distributor of different perforated ratio, and the results were verified by optical analysis. The results reveal that the smaller perforated ratio of the distributor can reduce the bubble size of the whole bed and reduce the pressure fluctuation. Thus, the gas–solid dispersion is uniform, and the fluidization quality of the fluidized bed is improved. However, the distributor has a limited effect area, which has a great influence on the lower part of the fluidized bed. As the gas velocity and the height increase, the effect becomes weaker. Under the operating conditions of 100 L/min, the perforated ratio of 0.91% can reduce the pressure drop of the entire bed by 65%. It can also reduce the pressure drop deviation in the lower part of the bed by more than 79%.

A series of Fe-substituted ZSM-23 samples with different Fe/(Fe + Al) ratios were synthesized. Combined characterization by Fourier transform infrared spectroscopic, ESR, and X-ray photoelectron sp...

Spacer insulator is an important component of gas insulated switchgear (GIS), and the performance degradation of spacer insulator will seriously affect the operation of GIS. In this paper, the temperature characteristic of spacer insulator’s material is tested and the temperature distribution of spacer insulator under operating condition is also measured. The electro-thermal and thermo-mechanical coupling formulation are presented respectively and finite element software is applied in simulation. The effect of multi-physics coupling on the performance of spacer insulator is analyzed. Results show that under the operating condition, the heat generated by current flow in central conductor may cause the temperature on spacer insulator to present a gradient distribution, resulting in the degradation of material performance; electric-thermal coupling effect may cause spacer insulator overheating and heat breakdown; and thermo-mechanical coupling effect may increase the probability of spacer insulator fracture. This paper can provide reference for fault analysis of spacer insulator.

The highly uniformed hybrid carbon material has been prepared by in-situ growth carbon nanotubes (CNTs) from metal organic frameworks, with the cobalt species as the catalyst for CNTs growth and dicyandiamide (DICY) as a sacrificial agent for the formation of graphitic carbon. The CNTs with extraordinary conductivity supply more electron transport to the cathode and make much more sense in enhancing the rate performance of the sulfur cathode. In the matrix, cobalt nanoparticles and heteroatom nitrogen can help in immobilizing sulfur species, leading to the improvement of polysulfide shutting. Moreover, the increased specific surface area and mesoporous channel enhance the sulfur loading and facilitate electrolyte diffusion. On integrating these fascinating benefits into one electrode material, as a result, the hybrid composite (CNT@Co N C/S) cathode presents a high initial capacity of 1316.1 mAh/g at the current rate of 0.1C. Even at high current rate of 5C, a decent capacity of 620.7 mAh/g can still be achieved. The capacity of hybrids materials can be maintained at 970 mAh/g after 500 cycles at 0.2C, and a capacity retention of 79.8%, revealing it great potential for energy storage application.

A new aptamer microarray method on the TiO2–porous silicon (PSi) surface was developed to simultaneously screen multiplex mycotoxins. The TiO2 nanolayer on the surface of PSi can enhance the fluorescence intensity 14 times than that of the thermally oxidized PSi. The aptamer fluorescence signal recovery principle was performed on the TiO2–PSi surface by hybridization duplex strand DNA from the mycotoxin aptamer and antiaptamer, respectively, labeled with fluorescence dye and quencher. The aptamer microarray can simultaneously screen for multiplex mycotoxins with a dynamic linear detection range of 0.1–10 ng/mL for ochratoxin A (OTA), 0.01–10 ng/mL for aflatoxins B1 (AFB1), and 0.001–10 ng/mL for fumonisin B1 (FB1) and limits of detection of 15.4, 1.48, and 0.21 pg/mL for OTA, AFB1, and FB1, respectively. The newly developed method shows good specificity and recovery rates. This method can provide a simple, sensitive, and cost-efficient platform for simultaneous screening of multiplex mycotoxins and can be...

A temperature-responsive, recyclable nanocatalyst was fabricated by composting the exfoliated molybdenum disulfide (MoS2) nanosheets with poly (N-isopropylacry lamide) (PNIPAM). The structure and morphology of MoS2/PNIPAM nanocatalyst was fully characterized by Fourier transform infrared spectroscopy (FT-IR), X-ray photoelectron spectroscopy (XPS), Thermogravimetry analysis (TGA), Scanning electron microscope (SEM) and Transmission electron microscopy (TEM). The temperature-responsive properties of the MoS2/PNIPAM nanocatalyst were confirmed by Dynamic Light Scattering (DLS) and Ultraviolet–visible ((UV–vis)) absorption spectroscopy. The catalytic activities of the MoS2/PNIPAM nanocatalyst were studied using the reduction reaction of 4-nitrophenol (4-NP) to 4-aminophenol (4-AP) as the model reaction. Results showed that the catalytic activity of the MoS2/PNIPAM nanocatalyst could be regulated by temperature. Furthermore, when the temperature went higher than the low critical solution temperature (LCST) of PNIPAM, the MoS2/PNIPAM nanocatalyst tended to aggregated to form bulk materials from homogeneous suspension.

Cotton fabric/LiFePO4 cathode material was synthesized via a conventional solvothemal method. XRD results revealed that all the patterns could be indexed as the olivine-type structured LiFePO4 with the space group of Pnma. SEM images showed that the obtained samples presented plate-type morphology. When the cotton fabric (soaked in the 0.1 M LiOH solutions)/LiFePO4 used as the cathode material for lithium-ion battery, it showed excellent cycle stability, i.e., an extremely low loss in the capacity of 7.8% after 200 cycles at 2 C, due to the enhanced electronic conductivity and Li-ion diffusion processes as also proved by the electrochemical impedance spectroscopy (EIS). Thus, this low cost cotton fabric decorated LiFePO4 composite is a promising cathode material for high-performance lithium-ion battery.

Air permeability is crucial to nanofibrous membrane applications, such as in wound dressing and membrane distillation. Herein, hierarchical structure membrane is prepared layer by layer with different fiber diameters, using electrospinning method. The results showed that with different layer arrangement results in different air permeability, and optimal condition is found.