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Three RF switches and a phase shifter are proposed using the conductive bridging random access memory (CBRAM) technique. The fabrication process is developed with the Nafion membrane on a high-resistivity silicon substrate. The equivalent circuit model is established for each memristive RF switch. The proposed switches and the phase shifter have been validated by the good agreement achieved among the simulated, measured, and modeled results. The experimental results show that the series planar switch has the ON-state insertion loss (IL) below 1.69 dB and the OFF-state isolation over 25 dB up to 10 GHz, with the actuation voltages of 6.1~7.8/-1.5~-2 V. The parallel metal-insulator-metal (MIM) switch has the small ON-state IL below 0.45 dB and the OFF-state isolation over 18.4 dB when biased with 0.8~3.7/-0.5~-0.9 V. The series MIM switch has the ON-state IL below 0.61 dB and the OFF-state isolation over 21.9 dB with 0.7~2.3/-0.5~-0.9 V. The series MIM switch shows a good comprehensive performance of low actuation voltage, good uniformity, low IL, moderate isolation, and independent control. The phase shifter is realized with four series MIM switches, which provides a phase shift of 45° ± 5° from 3.8 to 4.3 GHz with the in-band IL of 2.25 dB. Compared with the conventional RF switchable devices, the proposed devices have the advantages of nonvolatility and low power consumption. Without depending on the electron beam lithography process and high-temperature phase change, the proposed technique is promising for reconfigurable RF circuits with mass production and feasibility to various substrates.

A route is present for preparing porous titanium scaffolds with open and interconnected pore morphology through calcium thermal in-situ reduction of TiO precursor. Titanium and dioxide titanium powders, with ammonium carbonate as the space holder, were used to prepare porous precursor whose main phase is TiO by a sintering process. Then calcium vapor was conduced to reduce the precursor and CaO was removed by leaching to obtain porous titanium structures. The morphology, pore structure, phase analysis of porous titanium precursor and porous titanium scaffolds were investigated by means of XRD, SEM and EDS. The porosity was observed by Archimedes method. By this route, the porous titanium with multi-gradient pore sizes ranging from a few microns to several hundred microns was formed. The porous titanium is of multi-gradient pore size distribution of 100 μm bigger, 10 μm∼100 μm and 10 μm smaller. The micro-pores on the pore walls increases connectivity between the macro-pores throughout the porous titanium interior. The porous titanium obtained by this method has a porosity of 50–65% and a titanium content more than 99%.

In order to improve the safety, operability, and cleanability of the dust suppressant, this paper uses the surfactant monomers selected in the previous experiment as the main material formula and adds the inorganic salt as the synergist to prepare the dust suppressant for the PMX. The wetting property of the solution was characterized by the surface tension and contact angle of the pressed coal pieces. The sedimentation experiment was used to screen the compounding system of the surfactant. Finally, the dust suppressant was used to reduce the dust of the PMX in the coal dust simulation system. The results show that (1) the surfactant compounding system can effectively improve the wetting property and the sedimentation time of coal dust. The fast penetration T (0.06%), SDBS (0.15%), and APG (0.20%) are the preferred main ingredients. (2) Adding inorganic salts on the basis of compounding, according to the effect of inorganic salts on the effect of dust suppressant, it is concluded that NaCl (1.00%) is the best synergist. (3) In order to save costs, reduce the amount of surfactant. According to the simulated dust reduction experiment, formula N: anionic surfactant SDBS (0.06%), anionic surfactant fast-permeability T (0.06%), and inorganic salt NaCl (1.00%) are the best for PMX dust fall.

In this paper, a novel and effective process for removing lead and synthesizing glass–ceramics from the hazardous waste CRTs funnel glass and red mud was developed. Glass–ceramics was produced through an appropriate sintering treatment of the residual glass after lead from funnel glass was removed. Vacuum smelting results showed that the addition of red mud had contributed to enhance Pb removal from funnel glass as compared to the same process without red mud. When the red mud mass was added 60 wt%, more than 99.93% of Pb was successfully removed and the Pb content was reduced to 0.0093 wt%. Metallic lead with 99% purity was recycled. The sintering process showed that the CaO–Al2O3–SiO2 type glass–ceramics were synthesized with different microstructure crystallinity and morphology. Overall, the results demonstrated that red mud can not only enhance PbO removal from waste CRT funnel glass, but also fabricate glass–ceramics combining residual glass. Route of removing Pb and synthesizing glass–ceramics from waste CRTs funnel glass by red mud.

Purpose This paper aims to evaluate the corrosion resistance of fusion zones in different heat treated condition from laser welded Mg-Gd-Y alloys and analyze their intrinsic corrosion mechanism. Design/methodology/approach The corrosion behavior of fusion zone from laser-welded Mg-Gd-Y alloy joints in the as-welded, ageing and solution + ageing conditions was investigated in the 3.5 wt.% NaCl solution by immersion tests. Findings The corroded surface of as-welded fusion zone consists of dark and bright regions, and the bright regions were composed of high-density needle-like products, whereas some different extended direction of the cracks with lots of long ultrafine needle-shaped corrosion products appeared in the dark regions. The corrosion resistance of the fusion zone is slightly decreased after the ageing treatment. Originality/value The solution + ageing treated fusion zone exhibits the highest corrosion resistance than that of the as-welded and ageing treated state because of the full dissolution of the cathodic coarse eutectic compound, grains growth and relatively compact protective films. The inhomogeneous distribution of the β′ can somewhat improve the corrosion rate of solution + ageing treated fusion zone when compared with base metal.

A rapid preparation method of TiO2-x by thermal treatment using H2TiO3 as the precursor was proposed compared with the static hydrogenation thermal treatment process. Its adsorption properties of arsenic under visible light were explored and investigated as well. Various colors of TiO2-x were prepared and characterized via XRD, TEM, BET, and so on. The results indicate that the method of rapid preparation is feasible. The TiO2-x exhibits a larger particle size that varied from 10 nm to 2 μm, and deeper color products were obtained as the treatment temperature increased from 600 to 900 °C. Light yellow TiO2-x was prepared after increasing the temperature from 600 to 900 °C, Ti4O7 and Ti6O11 with a dark color were formed under a H2 atmosphere at 1500 °C. The arsenic adsorption performances of some samples under visible light were tested, and reveal a high efficiency of TiO2-x in the photocatalytic oxidation arsenic adsorption under visible light, the conversion ratio of As(III) photocatalytic oxidation fluctuates around 2.85 mgAsg-1 h-1. In the absence of visible light, the adsorption capacities for As(III) and As(V) are 3.7 and 42.7 mg/g, respectively, at pH = 3. Under visible light condition, the adsorption capacity of As(III) increases sharply to 15.6 mg/g, which provides the foundation for a new application of TiO2-x in the field of arsenic adsorption.

Development of denitration catalysts is highly important to controlling the level of NOx pollution. In this article, we report a novel CuO–MoO2–CeO2 catalyst with a yolk–albumen–shell structure supported on commercial γ-Al2O3 for the denitration study. The yolk catalyst CuO/γ-Al2O3 was first prepared with impregnation method by loading CuO on the γ-Al2O3 support, which provides a platform for further loading MnO, Cr2O3 or MoO2 as the albumen component. While measurements confirmed CuO–MoO2/γ-Al2O3 as the best choice, the final CuO–MoO2–CeO2/γ-Al2O3 yolk–albumen–shell catalyst was formed by loading CeO2 as the shell. The denitration performance of different catalysts in the presence or absence of SO2 was studied, followed by the investigation of denitration mechanism through XRD and SEM characterizations. The investigation reveals that the denitration performance of catalysts highly depends on their structures and compositions, which could be affected in the presence of SO2. In particular, the CuO–MoO2–CeO2/γ-Al2O3 catalyst, prepared under the conditions of roasting temperature of 400 °C, roasting time of 4 h and loading of 5%, shows outstanding SO2-resistance performance while its denitration efficiency is maintained between 81 and 83%.

The nonlinear refraction of silver nanoparticles (AgNPs) in n-hexane was studied by using the closed-aperture Z-scan technique with a 532 nm nanosecond laser. It was found that, the nonlinear refraction of AgNPs shows the coexistence and transformation from self-focusing to self-defocusing. Specifically, self-focusing occurs at low excitation intensity, self-defocusing occurs at high excitation intensity, and coexistence of self-focusing and self-defocusing occurs at relatively moderate excitation intensity. The experimental results were analysed and discussed in terms of third-order and fifth-order nonlinear refractive effect. Specifically, the self-focusing is caused by the positive third-order nonlinear refraction, the self-defocusing is induced by the negative fifth-order nonlinear refraction, and the transformation from the self-focusing to self-defocusing at medium excitation intensity is caused by the competition of third-order and fifth-order nonlinear refraction. Finally, the third-order refractive index and fifth-order refractive index were obtained.

Utilizing the in-situ reducing method, a reduced graphene oxide (rGO) paper for 13~14 um was obtained and exhibits great Terahertz (THz) absorbing capability. The absorption of rGO paper exceeds 43% in the whole frequency band from 0.3~1.2 THz and maximum absorption reaches 59.33% at 1.13 THz. This makes it possible to realize ultra-thin broadband THz absorbing materials.

The ZnO/Ni2S3 composite has been designed and in situ synthesized on Ni foam substrate by two steps of electrodeposition. ZnO was achieved on Ni foam by a traditional potentiostatic deposition, followed by cyclic voltammetric (CV) electrodeposition, to generate Ni2S3, where the introduction of ZnO provides abundant active sites for the subsequent Ni2S3 electrodeposition. The amount of deposit during CV electrodeposition can be adjusted by setting the number of sweep segment and scan rate, and the electrochemical characteristics of the products can be readily optimized. The synergistic effect between the ZnO as backbones and the deposited Ni2S3 as the shell enhances the electrochemical properties of the sample significantly, including a highly specific capacitance of 2.19 F cm−2 at 2 mA cm−2, good coulombic efficiency of 98%, and long-term cyclic stability at 82.35% (4000 cycles).

Polyaniline/poly(methylmethacrylate) (PANI/PMMA) microfiber coating were successfully deposited on carbon steel by electro-spinning and drop-cast methods, and their corrosion protection performances were evaluated in H2SO4. The results show the corrosion protection property of coating is outstanding with a certain amount of PANI (25 wt.%), especially for electro-spun coating. The reason of superior corrosion protection function of PANI electro-spun coating was investigated, which is primarily attributed to its better barrier protection, behaved as a lower porosity and enhanced adhesive ability. The outstanding corrosion protection performance of PANI/PMMA microfiber coatings encourages the wider application of electro-spun coatings in the corrosion protection area.

In contrast to commonly used approaches to improve data quality in diffusion weighted imaging, position-orientation adaptive smoothing (POAS) provides an edge-preserving post-processing approach. This study aims to investigate its potential and effects on image quality, diffusion metrics, and fiber tractography of the corticospinal tract in relation to non-post-processed and averaged data. 22 healthy volunteers were included in this study. For each volunteer five clinically applicable diffusion weighted imaging data sets were acquired and post-processed by standard averaging and POAS. POAS post-processing led to significantly higher signal-to-noise-ratios (p < 0.001), lower fractional anisotropy across the whole brain (p < 0.05) and reduced intra-subject variability of diffusion weighted imaging signal intensity and fractional anisotropy (p < 0.001, p = 0.006). Fiber tractography of the corticospinal tract resulted in significantly (p = 0.027, p = 0.014) larger tract volumes while fiber density was the lowest. Similarity across tractography results was highest for POAS post-processed data (p < 0.001). POAS post-processing enhances image quality, decreases the intra-subject variability of signal intensity and fractional anisotropy, increases fiber tract volume of the corticospinal tract, and leads to higher reproducibility of tractography results. Thus, POAS post-processing supports a reliable and more accurate fiber tractography of the corticospinal tract, being mandatory for the clinical use.

Polyethylenimine (PEI), a kind of cationic non-viral gene delivery vector, is capable of stable and efficient transgene expression for gene delivery. However, low transfection efficiency in vivo along with high toxicity limited the further application of gene therapy in the clinic. To enhance gene transfection performance and reduce cytotoxicity of polyethylenimine, branched polyethylenimine-derived cationic polymers BPEI25 k-man-S/L/M/H with different grafting degree with mannitol moieties were prepared and the transfection efficiency was evaluated. Among them, BPEI25 k-man-L showed the best transfection efficiency, lower toxicity, and significantly enhanced long-term systemic transgene expression for 96 h in vivo even at a single-dose administration. The results of cellular uptake mechanism and western-blot experiments revealed that the mannitol modification of BPEI25 k induced and up-regulated the phosphorylation of caveolin-1 and thus enhanced the caveolae-mediated cellular uptake. This class of gene delivery system highlights a paradigmatic approach for the development of novel and safe non-viral vectors for gene therapy.

Cathodic polarization antifouling has attracted attention because of environment-friendly property. We have developed a conductive PPy/resin coating with good electrochemical antifouling effects. However, its conductivity should be further improved to save the electric energy. In this work, a conductive Ag@PPy/resin composite was synthesized. Compared to PPy/resin coating, its conductivity was increased by 6 times, besides, its stability and 2e− oxygen reduction reaction (ORR) activity were obviously enhanced. And the antifouling effect under smaller cathodic voltage (−0.3 V) is improved, increasing the anti-fouling efficiency.

The uniaxial compression stress dependence of the phase transitions and dielectric properties of a potassium niobate (KNbO3) ferroelectric crystal were investigated using Landau–Ginsburg–Devonshire phenomenological theory. The results showed that (1) uniaxial stress along [001]c could induce a spontaneous polarization change from the [001]c direction to the [010]c or [100]c directions and from the [011]c, [101]c directions to the [110]c direction; (2) the cubic to tetragonal and the tetragonal to orthorhombic phase transition temperatures increased, while the orthorhombic to rhombohedral phase transition temperature decreased as the uniaxial stress was increased; and (3) spontaneous polarization increased as the uniaxial stress was increased for the tetragonal and orthorhombic phases. The uniaxial stress dependence of the dielectric susceptibility also showed that a flatter Gibbs free energy profile corresponds with a greater expandability, contractibility, and rotationality of the polarization (which indicates a higher dielectric susceptibility), while a steeper Gibbs free energy profile corresponds with a reduced expandability, contractibility, and rotation of the polarization (which indicates a lower dielectric susceptibility).

Cathodic polarization antifouling deserves attention because of its environmentally friendly nature and good sustainability. It has been proven that cathodic voltages applied on metal substrates exhibit outstanding antifouling effects. However, most metals immersed in marine environment are protected by insulated anticorrosive coatings, restricting the cathodic polarization applied on metals. This study developed a conducting polypyrrole (PPy)/acrylic resin coating (σ = 0.18 Scm−1), which can be applied in cathodic polarization antifouling. The good stability and electro-activity of PPy in the negative polarity zone in alkalescent NaCl solution were verified by linear sweep voltammetry (LSV), chronoamperometry (CA), cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS), demonstrating the feasibility of PPy as cathodic polarization material. Furthermore, the antifouling effects of PPy/acrylicresin coating on 24-h old Escherichia coli bacteria (E. coli) which formed on PPy/acrylic resin-coated plastic plate were measured under different cathodic potentials and treatment time, characterized by fluorescent microscope. The results suggest that at cathodic potential around −0.5 V (vs. saturated calomel electrode (SCE)), there was little trace of attached bacteria on the substrate after 20 min of treatment. PPy/acrylicresin-coated substrates were also subjected to repeated cycles of biofilm formation and electrochemical removal, where high removal efficiencies were maintained throughout the total polarization process. Under these conditions, the generation of hydrogen peroxide is believed to be responsible for the antifouling effects because of causing oxidative damage to cells, suggesting the potential of the proposed technology for application on insulated surfaces in various industrial settings.

A flash synthesis method of titanium suboxides (TSO) TinO2n-1 nanoparticles with Magneli phases by thermal plasma using rutile-phase metatitanic acid (H2TiO3) as the raw material was proposed and investigated, comparing with common sintering hydrogenation process of H2TiO3. TSO powders with diverse colors were prepared and characterized by means of XRD, SEM and TEM. The results showed Magneli phase nanoparticles with perfect spherical shape and particle size of 20–100 nm were rapidly synthesized by thermal plasma treatment under Ar and Ar/H2 atmospheres. Typical Magneli phases of Ti5O9 and Ti4O7 with peacock blue color were formed under argon atmosphere. An increase of hydrogen content in the atmosphere made nano-H2TiO3 efficiently reduced to form a different TSO phases with diverse colors of dark blue to blue black. Notably, parts of nanoparticles were of carbon shell/Magneli phase core structure. The UV–visible absorptivity and electric conductivity of samples were tested and the results indicate that thermal plasma is an efficient way to improve the optical and conductive properties of materials. But the electric resistivity of nano Magneli phase powders still keep 105–106 Ω.cm.

Transparent and flexible chitosan-based membranes containing antibacterial drugs were prepared through a casting/solvent evaporation method from suspension of chitosan floccule. To enhance mechanical properties, glycerin was incorporated into the floccule suspension to conjugate chitosan as a plasticizer. The mechanism of membrane formation is attributed to inter- and intro-hydrogen bonding between chitosan and glycerol molecules. The results showed that incorporation of glycerol has a significant influence on the properties of the chitosan membranes. With the increase of glycerol content, the tensile strength, swelling rate, water vapor permeability and wettability of membranes were significantly improved. In vitro enzymatic degradation revealed that the chitosan membrane had long-term stability regardless of the glycerol content. To enhance antibacterial properties, tetracycline hydrochloride (TH) and silver sulfadiazine (AgSD), representing the water-soluble and water-insoluble drug models, were integrated into the membranes, respectively. The results of controlled-release efficacy and inhibition zone indicate that the glycerol toughened chitosan membranes containing drugs have a promising future in treatment of bacterial infection as wound dressing.

A bifunctional tunable metamaterial composed of pattern metal structure, graphene, and strontium titanate (STO) film is proposed and studied numerically and theoretically. The dual plasmon-induced transparency (PIT) window is obtained by coupling the bright state cut wire (CW) and two pairs of dark state dual symmetric semiring resonators (DSSRs) with different parameters. Correspondingly, slow light effect can also be realized. When shifting independently, the Fermi level of the graphene strips, the amplitudes of the two PIT transparency windows and slow light effect can be tuned, respectively. In addition, when independently tuning the temperature of the metamaterial, the frequency of the dual PIT windows and slow light effect can be tuned. The physical mechanism of the dual-PIT was analyzed theoretically by using a three-harmonic oscillator model. The results show that the regulation function of the PIT peak results from the change of the oscillation damping at the dark state DSSRs by tuning conductivity of graphene. Our design presents a new structure to realize the bifunctional optical switch and slow light.

Based on the scaling problem on the outer surface of the steam generator tube in the secondary circuit condition of pressurized water reactor, the molecular dynamic was used to calculate the adsorption characteristics of Fe3O4. The trajectory, mean squared displacement, radial distribution function and adsorption energy of Fe3O4 agglomeration and deposition process were further analyzed through variation of temperature and concentration. When the temperature was between 510 K and 530 K, the diffusion coefficient of Fe2+ and OH− could reach the minimum value of 2.255 × 10-5 cm2/s and 2.638 × 10-5 cm2/s, respectively. During variation of Fe2+ concentration, the size of agglomerate particles increased continuously, and the diffusion coefficient of H2O can reach the minimum value of 3.78 × 10-5 cm2/s. Fe2+ with positive charges can effectively agglomerate with H2O and OH−, forming the tetrahedral and octahedral structures of Fe3O4 crystal. At this time, a small number of OH− were adsorbed at the interface of the matrix, forming the double electrical layer and affecting the deposition of agglomerated Fe3O4. Apart from this, high temperature is beneficial to inhibit scaling deposition in part. Likewise, low concentration of the dissolved Fe2+ and OH− can also lead to weaker deposition of agglomerated Fe3O4 on the outer scaling layer of the secondary side in the steam generator.

In a polymer electrolyte membrane electrolyzer cell (PEMEC), the two electrode compartments are separated by a polymer membrane. Liquid water is fed to the anode side, forming oxygen gas on the anode, and hydrogen gas on the cathode side, respectively. The respective designs of the flow field patterns are important to obtain a uniform distribution of flow, in combination with low-pressure drops, during operation. In this study, oxygen production in a manifold electrolyzer is investigated using the Computational Fluid Dynamics (CFD) method. The flow is considered unsteady, three-dimensional, and two-phase. A mixture model is applied to simulate the water consumption and oxygen production. The anode side is analyzed and after the reaction, gas bubbles are produced inside the lower surface of the electrode. The simulation is performed for 5 s. The results show that from the moment of start to 2 s is an important time for the formation of pressure and velocity balance inside the manifolds. In 0.75 s, the oxygen reaches its highest concentration and, due to its physical nature, begins to move from low to high levels in the manifold. Increasing the rate of oxygen production and reducing the pressure drop in the system can be controlled by the number of different channels.

Blast furnace slag (BFS), a large amount of industrial solid waste, is currently used to make mainly concrete and building bricks. There is no doubt that it is a waste of rich elements and oxides in the slag. In order to increase the utilization and use value of BFS, this article prepared it as a denitration catalyst. The alkaline oxides CaO, MgO and the acidic oxides Al2O3, SiO2 were used to modify the ground granulated blast furnace slag (GGBS). And it investigated the effect of the modified GGBS and alkalinity on denitration performance. Combining X-Ray fluorescence (XRF), Fourier transform infrared spectroscopy (FT-IR), X-ray diffraction (XRD) and scanning electron microscope (SEM) characterization, the results showed that: Alkaline oxides modified GGBS had good denitration performance, which benefited from –OH generated during the modification process. While acidic oxides modified GGBS hardly improved the denitration performance, because the acidic oxides would absorb the f-CaO in the slag. According to the calculation formula of slag alkalinity, the quaternary, ternary and binary alkalinity of 9 wt% MgO modified GGBS were 0.901, 1.262 and 1.089 respectively, and the denitration performance of the modified GGBS improved with the increase of alkalinity.

Cathodic voltage applied to metal substrata has been proven to exhibit useful antifouling properties due to the generation of H2O2, where the metal substratum is used as a cathode in the process. However, most metals immersed in a marine environment are protected by insulating (anticorrosive) coatings, restricting the cathodic polarization that can be applied to the metal. In this work, polyaniline-polymethyl methacrylate was found to have good stability and low background current density, as measured by linear sweep voltammetry (LSV), chronoamperometry (CA) and cyclic voltammetry (CV), suggesting potential for use of PANI-PMMA as a cathode material. The antifouling effects of the PANI-PMMA coating on 24-h-old Escherichia coli bacteria (E. coli) were measured under different cathodic potentials and different polarization times; the outstanding antifouling effect was verified by fluorescence microscopy. Keywords: PANI-PMMA, Stability, Cathode material, Cathodic polarization antifouling

The processing parameters of friction stir welding for 6061 aluminum alloy were optimized by using the orthogonal experimental design in the range analysis and variance analysis with the tensile strength and elongation as the parameters. The results show that the stirring speed is the key factor, even welding speed, pressure and stirring head working angle also influence welding quality. The highest tensile strength can reach to 251MPa as the elongation reached to 7.5% with the optimum parameters of rotating speed of 800r/min, welding speed of 200~220mm/min, pressure volume of 0.4mm and stirring head working angle of 3°. The weld nugget zone (NZ) is composed of uniform fine equiaxed grains, while thermo mechanically affected zone (TMAZ) is composed of slender coarse grains. The structure of heat affected zone (HAZ) is developed along the deformation direction with the effect of thermal cycle.The fracture morphology of the FSW joints shows ductile dimple features which validates the high ductility of the joint during the tensile testing.

An antibacterial and biodegradable composite hydrogel dressing integrated with microspheres is developed for drug delivery and wound healing. The mechanism of gelation is attributed to the Schiff-base reaction between aldehyde and amino groups of oxidized alginate (OAlg) and carboxymethyl chitosan (CMCS). To enhance antibacterial and mechanical properties, tetracycline hydrochloride (TH) loaded gelatin microspheres (GMs) were fabricated by an emulsion cross-linking method, followed by integrating into the OAlg-CMCS hydrogel to produce a composite gel dressing. In vitro gelation time, swelling, degradation, compressive modulus and rheological properties of the gel dressing were investigated as the function of microsphere ratios. With increasing ratios of microspheres from 10 to 40mg/mL, the composite dressing manifested shorter gelation time and lower swelling ratios, as well as higher mechanical strength. Comparing to other formulations, the gel dressing with 30mg/mL microspheres showed more suitable stabilities and mechanical properties for wound healing. Also, in vitro drug release results showed that the loaded TH could be sustained release from the composite gel dressing by contrast with pure hydrogels and microspheres. Furthermore, powerful bacteria growth inhibition effects against Escherichia coli and Staphylococcus aureus suggested that the composite gel dressing, especially the one with 30mg/mL GMs containing TH, has a promising future in treatment of bacterial infection.

An Al-Mg-Si alloy 6061 and an Al-Zn-Mg alloy 7A52 were joined by friction stir welding successfully. Pre- and post- heat treatment were employed to improve the strength of the weld. The results show a best weld joint with the lowest hardness of 100 HV in 6061 matrix, being achieved by post-solid-solution and subsequent two-stage artificial aging for the whole weld joint of the 7A52 and 6061 solid solution. Under this condition, the weld nugget zone (WNZ) is stronger than 6061 matrix but it has lower hardness than 7A52 matrix. The hardness of WNZ is contributed by the combination of &eta, &prime, and L precipitates, dynamically changes along with the ratios between the number of &eta, and L precipitates. The higher the number density of &eta, precipitates, the hardness of WNZ is closer to that of the 7A52 matrix. Otherwise, the higher number density of L precipitates, the hardness of WNZ is closer to that of 6061 matrix. The coexistence of &eta, and L precipitates is a direct result from the mixture of 7A52 and 6061 alloys achieved by stirring. Precipitates identification and composition analysis reveal a dynamic WNZ with constituent transition in hardness and composition.

The Ag/Ni(OH)2 composite electrode has been designed and in situ constructed on a copper substrate by combining electroless deposition technology with electrodeposition. The products can be directly used as a high performance binder free electrode. The synergistic effect between the Ag nanocubes (AgNCs) as backbones and the deposited Ni(OH)2 as the shell can significantly improve the electrochemical properties of the composite electrode. Moreover, this in situ growth strategy forms a strong bonding force of active materials to the substrate, which can improve the cycling performance and lower the equivalent series resistance. The Ag/Ni(OH)2 composite electrode exhibits enhanced electrochemical properties with a high specific capacitance of 3.704 F cm&minus, 2, coulombic efficiency of 88.3% and long-term cyclic stability.

The Ag/Ni(OH)2 composite has grown directly on Cu foam substrate via a modified galvanic displacement reaction between the mixed solution (AgNO3 and KBr) and Cu foam, followed by subsequent electrodeposition. Cu foam functions as a reducing agent and electrode substrate. The in situ growth strategy enables the active material to form a strong connection with the substrate, which is beneficial for the fast ionic/electronic transport and lowers the equivalent series resistance. On the other hand, the introduction of Ag improves the electrical conductivity of the material and increases the specific surface area, and even participates in the electrochemical reaction as an effective constituent. Such factors can significantly boost the electrochemical performances of the product, including a high specific capacitance of 1755[Formula: see text]F[Formula: see text]g[Formula: see text] at 2.5[Formula: see text]A[Formula: see text]g[Formula: see text] coupled with long-term cyclic stability at 83.87% (5000 cycles).

With the rapid development of information technology, a wavelength-tunable vertical cavity surface emitting laser (VCSEL) is urgently needed as an optical signal source in dense wavelength division multiplexing (DWDM). Liquid crystal tunable VCSEL realized by utilizing the birefringence characteristics of liquid crystal has the advantages of stable polarization, high reliability, continuous wavelength tuning. In this paper, a liquid crystal tunable VCSEL structure based on intracavity sub wavelength grating is designed, and the influence of liquid crystal layer and sub wavelength grating on the wavelength tuning characteristics of VCSEL are analyzed and studied in depth. The results show that the thickness of the liquid crystal layer in the tunable VCSEL structure not only affects the wavelength tuning range, but also determines the mode hopping in the tuning process. In addition, an effective refractive index antireflection layer is formed by designing the subwavelength grating structure, and the refractive index difference between the liquid crystal layer and the semiconductor layer is optimized to further improve the wavelength tuning range and tuning efficiency. When the center wavelength is 980 nm, the tuning range is increased by 42%, reaching 41 nm, and the wavelength tuning efficiency is increased by 41%. It provides a new method of designing the VCSEL laser with high beam quality and continuous wavelength tuning.

The covalently modified ureido-conjugated chitosan/TPP multifunctional nanoparticles have been developed as targeted nanomedicine delivery system for eradication of Helicobacter pylori. H. pylori can specifically express the urea transport protein on its membrane to transport urea into cytoplasm for urease to produce ammonia, which protects the bacterium in the acid milieu of stomach. The clinical applicability of topical antimicrobial agent is needed to eradicate H. pylori in the infected fundal area. In this study, we designed and synthesized two ureido-conjugated chitosan derivatives UCCs-1 and UCCs-2 for preparation of multifunctional nanoparticles. The process was optimized in order to prepare UCCs/TPP nanoparticles for encapsulation of amoxicillin. The results showed that the amoxicillin-UCCs/TPP nanoparticles exhibited favorable pH-sensitive characteristics, which could procrastinate the release of amoxicillin at gastric acids and enable the drug to deliver and target to H. pylori at its survival region effectively. Compared with unmodified amoxicillin-chitosan/TPP nanoparticles, a more specific and effective H. pylori growth inhibition was observed for amoxicillin-UCCs/TPP nanoparticles. Drug uptake analysis tested by flow cytometry and confocal laser scanning microscopy verified that the uptake of FITC-UCCs-2/TPP nanoparticles was associated with urea transport protein on the membrane of H. pylori and reduced with the addition of urea as competitive transport substrate. These findings suggest that the multifunctional amoxicillin-loaded nanoparticles have great potential for effective therapy of H. pylori infection. They may also serve as pharmacologically effective nanocarriers for oral targeted delivery of other therapeutic drugs to treat H. pylori.

Magneli phase materials offer attractive physical and electrochemical properties-high electrical conductivity similar to metals and excellent acid-base chemical stability, while core-shell nanostructures can protect the core from aggregating into large particles and often possess remarkable physicochemical properties compared with single-component structures. Herein, TinO2n-1 (n = 2–6, 8 and 9) particles with core-shell nanostructure were rapid-prepared by an extraordinary carbothermal reduction process of P25 powders using polyvinyl alcohol (PVA) reductant. The products synthesized at different temperatures were investigated by XRD, TEM, XPS, TG-DSC and UV–Vis. The results showed that carbon-coated TinO2n-1 powders were obtained within a few seconds in argon atmosphere, while the resistivity and BET surface area of TinO2n-1@C are 0.02–0.206 Ω cm and 4.62–14.6 m2 g−1, respectively. Notably, the carbon shell thickness varied from 2 nm to 11 nm and the average particle size of the Magneli phase core ranged from 30 nm to 100 nm with an increase in reduction temperature. The residual carbon in the typical Magneli phases of Ti5O9 and Ti4O7 was between 4.92 wt% to 5.91 wt%. In addition, the UV–visible absorptivity showed that samples had favourable optical absorption properties in the visible range. This work is expected to be helpful in developing a rapid, simple and practical approach to fabricate different core-shell TinO2n-1 powders.

A novel process for synthesizing vanadium powders via calcium vapor reduction of V2O3 under 10 Pa was investigated. The mixture of vanadium trioxide powders and calcium chloride as a flux was the feed preform, and was then reduced by calcium vapor. After reduction, the reduction samples was subjected to a leaching process, the vanadium powders was synthesized by drying and dehydrogenating of the leaching products. The XRD and SEM results of the dehydrogenation products indicated that vanadium were produced and the V particles transformed into clear antler-shaped particles. Vanadium powders (98 wt% V) with 25 ppm H, 1300 ppm N, 1500 ppm O was finally obtained after a dehydrogenation process by Oxygen-nitrogen combined tester (ONH-2000).

In order to broaden the abilities of injectable hydrogel scaffolds, a self-healing chitosan/alginate hydrogel encapsulated with magnetic gelatin microspheres (MGMs) was prepared for anti-cancer drug delivery and soft tissue engineering. The hydrogel was formulated by cross-linking carboxyethyl chitosan (CEC) and oxidized alginate (OAlg) via the Schiff-base reaction. To strengthen the mechanical and biological capabilities of hydrogel, MGMs containing 5-fluorouracil (5-Fu) were prepared by an emulsion cross-linking method. In vitro gelation time, swelling ratio, degradation, compressive modulus and rheological behaviors were tested to monitor the effect of MGMs on the CEC-OAlg hydrogel. With a concentration of 30 mg/mL MGMs, the composite hydrogel provided with the suitable performance and showed excellent self-healing ability under physiological condition. Moreover, this composite hydrogel showed the sustained in vitro drug release compared with control MGMs and CEC-OAlg hydrogel. Our results demonstrated that this magnetic and self-healing CEC-OAlg hydrogel scaffold encapsulated MGMs containing 5-Fu was expected to be a platform for drug delivery and soft tissue engineering.

The thermogravimetric method was selected for investigating the evaporation of Sb2S3 in the pressure range of 50–300 Pa and in the temperature range of 823–1123 K, the gas phase diffusion was the rate-determining step for Sb2S3. The volatilization rate was related to the temperature and pressure, that the logarithm of volatilization rate yielded a line with the reciprocal of temperature and pressure. The volatilization rate for Sb2S3 was between 0–0.023 g·cm−2·s. The apparent activation energy was between 65.8 and 60.6 kJ/mol.

Non-viral nanovectors have attracted much attention owing to their ability to condense genetic materials and their ease of modification. However, their poor stability, low biocompatibility and gene degradation in endosomes or lysosomes has significantly hampered their application in vivo and in the clinic. In an attempt to overcome these difficulties a series of bovine serum albumin (BSA)-calcium phosphate (CaP) nanoparticles were constructed. The CaP condenses with DNA to form nanocomplexes coated with a biomimetic corona of BSA. Such complexes may retain the inherent endocytosis profile of BSA, with improved biocompatibility. In particular the transgene performance may be enhanced by stimulating the cellular uptake pathway via caveolae-mediated endocytosis. Two methods were employed to construct and optimize the formulation of BSA-CaP nanomaterials. The optimized BSA-CaP-50-M2 nanoparticles prepared by our second method exhibited good stability, negligible cytotoxicity and enhanced transgene performance with long-term expression for 72 h in vivo even with a single dose. Determination of the cellular uptake pathway and Western blot revealed that cellular uptake of the designed BSA-CaP-50-M2 nanoparticles was mainly via caveolae-mediated endocytosis in a non-degradative pathway in which the biomimetic uptake profile of BSA was retained.

Two types of white organic light-emitting devices (WOLED) containing a layered light-emitting region composed of a single blue-emitting host and different fluorescent dopants (blue and orange) were fabricated. The efficiency, lifetime, brightness, spectral voltage-dependence and white balance of devices were investigated. The results show that the performance of the devices strongly depends on the stack order of two emitting layers and the thickness of the emitting layer. It is found that the WOLED with an EML sequence of orange/blue (from anode to cathode) shows better stability than that with an EML sequence of blue/orange. It is due to the rubrene in orange emitting layer that acts as hole-trap sites and captures the passing holes and hence balances the concentration of electrons and holes. The optimized white device exhibits a favorable CIE coordinates (0.3201, 0.3459) which is close to the standard white light. ©, 2015, Chines Academy of Sciences. All right reserved.

Future Martian missions might carry acoustic anemometer, microphone, or ultrasound inspector. These Martian acoustic probes all need to be specifically designed to adapt to the tenuous Martian atmosphere. To aid the design, experiments have been carried out to measure the sound speeds and the absorption coefficients of ultrasound pulses in a vacuum chamber filled with 600–1000 Pa CO 2 gas. Results show that the sound speed barely changes with the gas pressure. And the average speed in the 288 K air and CO 2 are 340.2 and 269.1 m/s. The wave attenuation in the 600–1000 Pa CO 2 is stronger than that of the air. And the absorption coefficient in the air increases with the dropping pressure. However, the variation between the absorption coefficient and the gas pressure is very complicated for 21–40 kHz pulses in the CO 2 .

This study explores the feasibility of polyaniline-TiO2 coatings for photocathodic antifouling: antibacterial effect. PANI-TiO2 composites were prepared by chemical polymerization of polyaniline (PANI) in the presence of anatase TiO2, followed by dispersion of the resulting PANI-TiO2 composite in an acrylic resin for coating applications. The incorporation of PANI resulted in sensitization of the TiO2 to visible light, resulting in efficient electron and hole transfer between the PANI and TiO2 components. Under UV–vis illumination, the balanced potential of the PANI-TiO2 coating on 316 L stainless steel in a 3.5 wt.% NaCl solution was lowered to −0.4 V (vs. a saturated calomel electrode), sufficient to achieve cathodic protection of the stainless steel. The PANI-TiO2 coating also possessed good antimicrobial activity under UV–vis illumination for 30 min (efficiency > 70%). The antibacterial properties of the PANI-TiO2 coating can be attributed to the generation of H2O2 or other reactive oxygen species through photovoltaic effects, which cause oxidative damage to E. coli cells. This work confirms the feasibility of using PANI-TiO2 coatings to prevent biofouling (especially for fouling raised by the bacterial) of steels in marine environments.

Transparent and flexible alginate-based membranes containing antibacterial drugs were prepared by a casting/solvent evaporation method from alginate solution mixed with chitosan floccule (CSF) and oxidized sodium alginate (OAlg). To improve the properties of the membranes, CSF and OAlg were added to the alginate solution in different ratios. The mechanism of membrane formation is attributed to two aspects: Schiff-base cross-linking between CSF and OAlg; ion cross-linking between sodium alginate and CaCl2. The results showed that the incorporation of CSF and OAlg had a significant effect on the properties of the alginate membrane. With the change in the ratio between CSF and OAlg, the tensile strength, swelling rate, water vapor permeability, wettability and degradation stability of the membranes were significantly changed. In order to enhance the anti-bacterial properties, clindamycin (DA) and silver sulfadiazine (AgSD), which represent water-soluble and water-insoluble drug models, were integrated into the membrane, respectively. The results of controlled release effects and inhibition zones indicate that the alginate membranes containing drugs have a promising future in treatment of bacterial infection as wound dressing.

Hierarchical Ag@Ni(OH)2 nanospheres were achieved directly on copper foam substrate through a convenient two-step process. Ag nanoflowers were formed on copper substrate by galvanic replacement technology between AgNO3 and copper foam followed by electrodeposition of a layer of Ni(OH)2. Ag nanostructures as cores not only dominated the final morphology of the composites, but also improved the electrical conductivity, increased the specific surface area of the active electrode material, and even directly participated in the electrochemical reactions. The resulted Ag@Ni(OH)2 nanospheres could be directly used as high-performance binder-free electrodes and exhibited enhanced electrochemical performance with a high specific capacitance of 1.864 F cm&minus, 2 and long cycling lifespans of 90.43% capacity retaining after 3000 cycles.