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Abstract: In this paper anode support was fabricated by tape casting method using SDC-50 wt.% NiO slurry, then printed the Ce0.8Sm0.2O1.9 (SDC) electrolyte on the green piece which is cut out from the dried slurry piece. After at 90 °C drying for 14 h and co-sintered at 1350 °C for 10 h, get the Φ70 mm anode support and electrolyte planar bilayer. Based on the observation of photos and scanning electron microscopy (SEM) indicated that bilayer owns the flat anode support substrate, and the highly dense, crack free electrolyte film which is 12 μm in thickness. Small disks which were cut out from the Φ70 mm bilayer structure electrochemically were examined in a single button-cell mode incorporating a SDC-60 wt.% La0.5Sr0.5Co0.8Fe0.2O3 composite cathode. The single cell was tested at 450 °C∼600 °C, an open-circuit voltage (OCV) of 0.94 V and the maximum power density of 797 mV cm−2 achieved with dry hydrogen as fuel gas and air as oxidant gas at 600 °C. [Copyright &y& Elsevier]

Cu(OH)2 nanoribbon arrays were synthesized by a simple room-temperature solution reaction for the first time, which exhibited noticeable hydrogen storage capacity and large BET surface area. [ABSTRACT FROM AUTHOR]

The Li2CO3--Na2CO3--K2CO3 carbonate system exhibits superior sulfur interception capacity and thermodynamic stability in the molten salt oxidation (MSO) of cation exchange resins (CERs) with high sulfur content. However, the spent salt from the MSO process cannot be reused to reduce the operating cost and further improve the reduction ratio. Therefore, the optimal oxygen equivalent for treatment is obtained by thermodynamic equilibrium analysis of the MSO process of CERs as 1.08 multiples of the theoretical oxygen demand and the corresponding approximate chemical formula in this work. The results of the equilibrium analysis are used as the basis to propose a replenishment cycle for the MSO process (MSO-RC), which replenishes the consumed carbonate to restore the SO2 adsorption capacity and treatment capacity of the spent salt. During the experiments, the oxidation efficiencies of MSO-RC are higher than 99%, and the volume reduction ratio is improved by 12% compared with the traditional MSO. In addition, the MSO-RC maintains sulfur interception rates above 80% across multiple cycles and preserves over 94.7% Li2CO3 by adding cost-effective Na2CO3 and K2CO3 into the molten salt system. The MSO-RC process significantly improves the efficiency of process operation with lower operational costs. [ABSTRACT FROM AUTHOR]

As nitric oxide (NO) plays significant roles in a variety of physiological processes, the capability for real-time and accurate detection of NO in live organisms is in great demand. Traditional assessments of NO rely on indirect colorimetric techniques or electrochemical sensors that often comprise rigid constituent materials and can hardly satisfy sensitivity and spatial resolution simultaneously. Here, we report a flexible and highly sensitive biosensor based on organic electrochemical transistors (OECTs) capable of continuous and wireless detection of NO in biological systems. By modifying the geometry of the active channel and the gate electrodes of OECTs, devices achieve optimum signal amplification of NO. The sensor exhibits a low response limit, a wide linear range, high sensitivity, and excellent selectivity, with a miniaturized active sensing region compared with a conventional electrochemical sensor. The device demonstrates continuous detection of the nanomolar range of NO in cultured cells for hours without significant signal drift. Real-time and wireless measurement of NO is accomplished for 8 d in the articular cavity of New Zealand White rabbits with anterior cruciate ligament (ACL) rupture injuries. The observed high level of NO is associated with the onset of osteoarthritis (OA) at the later stage. The proposed device platform could provide critical information for the early diagnosis of chronic diseases and timely medical intervention to optimize therapeutic efficacy. [ABSTRACT FROM AUTHOR]

Mg-5Li-5Al-3Zn-xCd(x=0,2,3,4,5) alloys were prepared. The densities of these alloys were measured with Archimedes' method. The influence of Cd element on the microstructure and the properties of these alloys were also studied. The results indicate that these alloys possess low density ranging from 1.5 to 1.7 g·cm-3. The addition of Cd has the refining effect on the α-Mg phase and causes the formation of Mg3Cd intermetallic compound. The refinement and the formation of Mg3Cd improve the mechanical properties of alloys. When the Cd content is 3 wt.%, the tensile strength of alloy reaches its peak value(288 MPa). [ABSTRACT FROM AUTHOR]

To meet the demand of modern acoustic absorbing material for which acoustic absorbing frequency region can be readily tailored, we introduced woodpile structure into locally resonant phononic crystal (LRPC) and fabricated an underwater acoustic absorbing material, which is called locally resonant phononic woodpile (LRPW). Experimental results show that LRPW has a strong capability of absorbing sound in a wide frequency range. Further theoretical research revealed that LRPC units and woodpile structure in LRPW play an important role in realization of wide band underwater strong acoustic absorption. [ABSTRACT FROM AUTHOR]

Mg-5Li-1Al (LA51) and Mg-5Li-1Al-0.5Y (LA51-0.5Y) alloys were smelted and rolled with different accumulated strains (36% and 68%) and rolling temperatures (373 K and 573 K). The microstructure, mechanical properties, fracture morphology and texture of the specimens were investigated. Results show that, due to the PSN (particle stimulate nucleation) mechanism, the addition of 0.5 wt.% Y improves the deformation resistance and weakens the basal texture of LA51 alloy. The effect of Y on UTS (ultimate tensile strength) of as-rolled alloys is more obvious than that of the as-cast alloy. Accumulated strain and rolling temperature could influence the twinning number, slip systems and DRX (dynamic recrystallization), thus affecting the microstructure and mechanical properties of the alloy. Under the proper combination of the above factors, the as-rolled LA51-0.5Y alloy with an accumulated strain of 68% at 573 K possesses the best comprehensive mechanical properties. [ABSTRACT FROM AUTHOR]

Many modern technologies rely on the functional materials that are subject to their phase purity. The topic of obtaining pure crystals from the concomitant allotropes is ever before the eyes of numerous researchers. Here we adopt a template-inducing route and obtain the isolated allotropes located in the appointed regions in the same reaction system. As a typical example, well-defined individual face-centered cubic and orthorhombic ZnSnO3 crystals were successfully synthesized assisted by a ZnO inducing template or without it in an identical solution, respectively. And the different growing mechanisms of the ZnSnO3 allotropes were also proposed, which takes a pivotal step toward the realization of allotropes dividing. Moreover, the two individual pure-phased ZnSnO3 allotropes obtained in one reaction system exhibit porous microspherical morphologies constructed by the tiny nanograins, resulting in their high sensitivities to ethanol with fast response and recovery and good selectivity and stability. [ABSTRACT FROM AUTHOR]

Binary metal oxide MnCo2O4 nanosheets wrapped on a hollow activated carbon shell (C@MnCo2O4) were successfully synthesized through a facile hydrothermal method followed by a calcination process. The novel structure of a flower-like C@MnCo2O4 composite, which consists in a good conductive carbon shell and well interconnected nanosheets, can efficiently facilitate electrolyte penetration and offers an expedite transport path for ions and electrons. Notably, the large surface of the hybrid composite (347 m² g-1) can provide a large amount of active sites, which evidently accommodates the strain during cycling. Benefiting from this elegant combination and the effectively mesoporous structure, the specific capacitance of the C@MnCo2O4 composite can be achieved as high as 728.4 F g-1, which is, to the best of our knowledge, the highest value so far reported for MnCo2O4 based electrode materials. In addition, the C@MnCo2O4 composite exhibits enhanced rate capability and an excellent cycling stability of 95.9% retention after 1000 cycles at a high current density of 8 A g-1. Therefore, the desirable integrated electrical performance allows it to be a promising electrode material for supercapacitor applications. [ABSTRACT FROM AUTHOR]

A novel Mg-6Ho-1Zn alloy was successfully prepared, which had a good combination of mechanical properties and corrosion resistance due to the formation of profuse nano-spaced basal plane stacking faults (SFs). The ultimate tensile strength (UTS), tensile yield strength (TYS) and elongation were 325 MPa, 224 MPa and 17%, respectively. More importantly, the alloy with SFs presented a uniform corrosion behavior in simulated body fluid (SBF) with a low corrosion rate of about 0.5 mm/year, which could avoid rapid reduction in mechanical integrity. The performance of the alloy with SFs could be further improved by optimizing the microstructure. The investigation suggests that the alloys with SFs are promising biodegradable implant materials. [ABSTRACT FROM AUTHOR]

The high quality Mg-xYmm (x=6, 9, 12)-4Zn (Ymm=Y-rich misch metal, wt%) alloy ingots with diameter of 90-95mm and length of 600mm were successfully fabricated by water-cooled mold casting, and the microstructure and tensile properties have been investigated. The results demonstrated that the alloys contained four secondary phases: a plenty of 18R LPSO and 14H LPSO phases and a few of Mg=sub=3=/sub=Zn=sub=3=/sub=RE=sub=2=/sub= and Mg=sub=24=/sub=Y=sub=5=/sub=-type compounds. The ultimate tensile strength of Mg-12Ymm-4Zn alloy could keep above 130MPa until 400°C. The excellent high-temperature strength was mainly attributed to dense LPSO lamellae strengthening Mg matrix and network-like LPSO phase reinforcing grain boundaries. [ABSTRACT FROM AUTHOR]

Highly uniform α-NaYF4:Yb/Er hollow microspheres have been successfully prepared via a simple two-step route. First, the core-shell structured MF@Y(OH)CO3:Yb/Er precursor was fabricated by a urea-based homogeneous precipitation method using colloidal melamine formaldehyde (MF) microspheres as template. Then the Y(OH)CO3:Yb/Er precursor was transformed into hollow NaYF4:Yb/Er (α and β mixed phase) by a subsequent solvothermal method, and MF microspheres were dissolved in the solvent simultaneously. The mixed phase of NaYF4:Yb/Er was transferred into pure α-NaYF4:Yb/Er by calcination. The as-prepared hollow microspheres were well characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), energy-dispersive X-ray spectrum (EDS), Fourier transform infrared spectroscopy (FT-IR), thermogravimetric analysis (TGA), and upconversion (UC) luminescence spectroscopy. It is found that the template can be removed without additional calcination or etching process. α-NaYF4:Yb/Er hollow microspheres exhibit bright upconversion (UC) luminescence under 980 nm laser diode (LD) excitation. Furthermore, the hollow microspheres show sustained and pH-dependent doxorubicin hydrochloride (DOX) release properties; in particular, the emission intensity increases with the release amount of drug, making the release process able to be tracked or monitored by the change of the emission intensity, which demonstrates the high potential of this kind of hollow fluorescent material in drug delivery fields. [ABSTRACT FROM AUTHOR]

A hybrid chemically converted graphene nanosheet/Ni2ﰉ矺嚲窷 double-hydroxide (GNS/LDH) composite for supercapacitor material has been fabricated by a hydrothermal method. Scanning electron microscopy and transmission electron microscopy results reveal that Ni2ﰉ矸냇 platelets homogeneously grew onto the surfaces of the GNSs as spacers to keep the neighboring sheets separate. Electrochemical properties were characterized by cyclic voltammetry, galvanostatic charge/discharge measurements, and electrochemical impedance spectroscopy. The composite exhibits a maximum specific capacitance of 781.5 F/g and excellent cycle life with an increase of the specific capacitance of 38.07% after 50 cycle tests. Even after 200 cycle tests, the increase of the capacitance is 22.56% compared with the initial capacitance. [ABSTRACT FROM AUTHOR]

The goal of this study is to prepare hydrotalcite pellets and validate their potential utility in catalysts and catalysts support. Hydrotalcite pellets were synthesized by urea hydrolysis. Urea hydrolysis can provide both carbonate as the intercalated anion and hydroxyl anions to form Mg–Al layered double hydroxide (LDH) with carbonate intercalation. Urea hydrolysis was also used to generate NH which plays a critical role in the process of synthesis hydrotalcite pellets. Mechanism of the formation hydrotalcite pellets was also discussed. The as-prepared samples were well characterized by X-ray diffraction, scanning electron microscopy, transmission electronic microscope, N adsorption/desorption, and Fourier transform infrared spectroscopy, respectively. The results revealed that the hydrotalcite pellets were well-crystallized and formed by self-assembly of hexagonal platelets LDHs. The present work suggests that it is possible to grow hydrotalcite pellets directly through one-step aqueous solution-phase chemical route under controlled conditions. [ABSTRACT FROM AUTHOR]

1 wt% La-rich RE was added into the alloy of Mg–6Li–1.5Al. The influence of the RE addition on the microstructure and mechanical properties of the alloy and the deformation behavior of this alloy were investigated. The strengthening mechanisms of the alloy were also studied. Results show that the addition of RE can refine the grain and improve the strength and elongation of the alloy. Extrusion and rolling can improve the strength to a large extent. The strengthening mechanisms for this alloy are mainly the refining strengthening and dispersion strengthening. [ABSTRACT FROM AUTHOR]

Chrysalis-like morphologies of CuO have been synthesized in large-quantity via a simple chemical deposition method without the use of any complex instruments and reagents. CuO nanocrystals showed a different morphology at three different temperatures, 25, 60 and 100°C. The particle size, morphology and crystal structure of the samples were characterized by transmission electron microscopy (TEM), scanning electron microscopy (SEM), X-ray diffraction (XRD) and Raman spectra. The catalytic effect of CuO nanoparticles on the decomposition of ammonium perchlorate (AP) was investigated by STA 409 PC thermal analyzer at a heating rate of 10°C min-1 from 35 to 500°C. Compared with the thermal decomposition of pure AP, the addition of CuO nanoparticles decreased the decomposition temperature of AP by about 85°C. [ABSTRACT FROM AUTHOR]

Nanoplatelets of metal oxides with interesting porous structure were obtained by thermal treatment of Ni/Al hydrotalcite. Structural and surface properties of the porous oxides were characterized by X-ray diffraction (XRD), transmission electron microscopy (TEM and HRTEM), and N2 adsorption–desorption. The electrochemical performance of the electrodes was investigated by cyclic voltammetry, electrochemical impedance spectroscopy and constant current charge–discharge measurements. Ni/Al hydrotalcite calcined at 450 °C (NA-450) displayed a maximum specific capacitance (419.0 F g−1) due to the porous structure with the highest specific surface area (142.3 m2 g−1) and small pore size (4.4 nm). The present study shows the potential of NiO nanoplatelets composite material for electrochemical pseudo-capacitors. [ABSTRACT FROM AUTHOR]

Abstract  CuO shuttle-like and flower-like nanocrystals were synthesized through a one-step, low-temperature solution-phase method in the presence of a cation surfactant, hexadecyl trimethyl ammonium bromide. These nanocrystals were studied as an additive for promoting the thermal decomposition of ammonium perchlorate (AP). With the addition of CuO shuttle-like and flower-like nanocrystals, the thermal decomposition temperature of AP decreased. The structure, particle size, and morphology of resulting CuO powders were characterized by X-ray diffraction, scanning electron microscopy, and transmission electron microscopy. Thermogravimetric analysis technique was applied to investigate the thermal decomposition of mixtures of AP and as-prepared CuO nanocrystals. [ABSTRACT FROM AUTHOR]

Microstructural characterization of as-cast and extruded experimental alloys as (A) Mg-6.86Li-3.02Al-1.12Ce-0.7Ca (B) Mg-8.15Li-3.07Al-1.12Ce-0.72Ca (C) Mg-10.54Li-3.54Al-1.23Ce-0.94Ca are researched in this paper. The results show that the as-cast specimens of (A) and (B) are composed of α (Mg) phase, β (Li) phase, rod-like and bulk Al2Ce compound. On the other hand, β phase (Li), bulk and rod-like Al2Ce compound, Al2Ca compound at boundaries are observed in the as-cast (C) alloy. The addition of Ce and Ca also shows in the microstructure the presence of Al-Ce-Ca phase, a solid solution of Ca in Al2Ce compound. In the extruding alloys, the microstructure is refined and the β phase has the effect of coordination during deformation. The long rod-like and the bulk compounds become short rods and fine clumps distributing evenly in the extruding direction after extruding process. The microstructure of extruded Mg-10.54Li-3.54Al-1.23Ce-0.94Ca alloy testified the existence of eutectic structure. [ABSTRACT FROM AUTHOR]

Lysozyme crystallization was conducted in the ionic liquid IL 1butyl3methylimidizolium tetrafluoroborate [BMIm][BF4] with different bufferIL proportions. It was found that the addition of [BMIm][BF4] could promote the crystallization process, during which more lager single crystals with controllable morphologies could be obtained due to the manageable crystal growth velocity. A probable explanation was proposed based on the influence of the ionic polarization and kinetics in the lysozyme crystallization. Moreover, the transform in coordination number and the relative growth rate of different crystal faces were discussed. © 2008 WILEYVCH Verlag GmbH & Co. KGaA, Weinheim [ABSTRACT FROM AUTHOR]

Abstract: Anodic films were prepared on the AZ31 magnesium alloy in alkaline borate solution with or without addition of titania sol under the constant potential of 50V (dc) for 10min at room temperature. The morphology of the anodic films was observed by scanning electron microscope (SEM). The corrosion resistance of the anodic films was evaluated in 3.5% NaCl solution using fast anti-acid test, potentiodynamic polarization and electrochemical impedance spectroscopy (EIS). The anodic film formed in borate solution with addition of 4% titania sol has superior uniform surface and higher corrosion resistance than in other conditions. [Copyright &y& Elsevier]

Synthesis of flower-shaped ZnO nanostructures composed of ZnO nanosticks was achieved by the solution process using zinc acetate dihydrate, sodium hydroxide and polyethylene glycol-20000 (PEG-20000) at 180°C for 4 h. The diameter of individual nanosticks was about 100 nm. Detailed structure characterizations demonstrate that the synthesized products are wurtzite hexagonal phase, grown along the [001] direction. The infrared (IR) spectrum shows the standard peak of zinc oxide at 571 cm-1. Raman scattering exhibits a sharp and strong E2 mode at 441 cm-1 which further confirms the good crystal and wurtzite hexagonal phase of the grown nanostructures. [ABSTRACT FROM AUTHOR]

Abstract  Delicate double tower-like ZnO have been fabricated through the decomposition of the zinc nitrate hexahydrate (Zn(NO3)26H2O). The phase transformation and morphology evolution of the products were carefully studied and investigated with X-ray diffraction, scanning electron microscopy, transmission electron microscopy, X-ray photoelectron spectroscopy, and Raman spectra. The resultant results indicated that the obtained double tower-like ZnO materials possess pure wurtzite hexagonal phase, growing along the [100] direction. A reasonable formation mechanism was also presented in this paper. [ABSTRACT FROM AUTHOR]

Ultra-thin 3 nm ZnSnO3nanorods were successfully prepared, which not only exhibit high sensitivity to ethanol at relatively low temperature, but also good selectivity. [ABSTRACT FROM AUTHOR]

The nanocrystalline CuO powders were prepared by precipitation method using Cu(NO3)2 as copper raw material, water and ethanol as dispersants, and NaOH and ammonia solution as precipitates. The structure, particle size and morphology of resulting CuO powders were characterized by X-ray diffraction (XRD), field-emission scanning electron microscopy (SEM) and transmission electron microscopy (TEM). The mechanism of CuO formation was discussed. [ABSTRACT FROM AUTHOR]

The construction of semiconductor composites is known as a powerful method used to realize the spatial separation of electrons and the holes in them, which can result in more electrons or holes and increase the dispersion of oxygen ions ( and O−) (one of the most critical factors for their gas-sensing properties) on the surface of the semiconductor gas sensor. In this work, using 1D ZnO/ZnSnO3 nanoarrays as an example, which are prepared through a hetero-epitaxial growing process to construct a chemically bonded interface, the above strategy to attain a better semiconductor gas-sensing property has been realized. Compared with single ZnSnO3 nanotubes and no-matching ZnO/ZnSnO3 nanoarrays gas sensors, it has been proven by x-ray photoelectron spectroscopy and photoluminescence spectrum examination that the as-obtained ZnO/ZnSnO3 sensor showed a greatly increased quantity of active surface electrons with exceptional responses to trace target gases and much lower optimum working temperatures (less than about 170 °C). For example, the as-obtained ZnO/ZnSnO3 sensor exhibited an obvious response and short response/recovery time (less than 10 s) towards trace H2S gas (a detection limit down to 700 ppb). The high responses and dynamic repeatability observed in these sensors reveal that the strategy based on the as-presented electron and hole separation is reliable for improving the gas-sensing properties of semiconductors. [ABSTRACT FROM AUTHOR]