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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]

In order to comprehensively improve the strength, toughness, flame retardancy, smoke suppression, and thermal stability of polypropylene (PP), layered double hydroxide (LDH) Ni0.2Mg2.8Al-LDH was synthesized by a coprecipitation method coupled with the microwave-hydrothermal treatment. The X-ray diffraction (XRD), morphology, mechanical, thermal, and fire properties for PP composites containing 1 wt %-20 wt%Ni0.2Mg2.8Al-LDH were investigated. The cone calorimeter tests confirm that the peak heat release rate (pk-HRR) of PP-20%LDH was decreased to 500 kW/m2 from the 1057 kW/m2 of PP. The pk-HRR, average mass loss rate (AMLR) and effective heat of combustion (EHC) analysis indicates that the condensed phase fire retardant mechanism of Ni0.2Mg2.8Al-LDH in the composites. The production rate and mean release yield of CO for composites gradually decrease as Ni0.2Mg2.8Al-LDH increases in the PP matrix. Thermal analysis indicates that the decomposition temperature for PP-5%LDH and PP-10%LDH is 34 °C higher than that of the pure PP. The mechanical tests reveal that the tensile strength of PP-1%LDH is 7.9 MPa higher than that of the pure PP. Furthermore, the elongation at break of PP-10%LDH is 361% higher than PP. In this work, the synthetic LDH Ni0.2Mg2.8Al-LDH can be used as a flame retardant, smoke suppressant, thermal stabilizer, reinforcing, and toughening agent of PP products. [ABSTRACT FROM AUTHOR]

The effects of transition metals on the hydrophobicity of nano-structured layered double hydroxides (LDHs) and the compatibility of LDHs/ethylene vinyl acetate (EVA) composites have seldom been reported. NiMgAl-LDHs slightly surface-modified with stearate and doped with transition metal cations (Mn2+, Co2+, Cu2+, Zn2+) are investigated. Compared to the pure EVA, not only were the maximal degradation-rate temperatures (Tmax) of the ethylene-based chains enhanced, but also the smoke production rate (SPR) and the production rate of CO (COP) were sharply decreased for all the composites. Most importantly, a new flame retardant mechanism was found, namely the peak heat release rate (pk-HRR) time, which directly depends on the peak production rate of CO2 (pk-CO2) time for EVA and all composites by cone calorimeter test. Moreover, the Mn-doped LDH S--NiMgAl--Mn shows more uniform dispersion and better interfacial compatibility in the EVA matrix. The cone calorimetric residue of S--NiMgAl--Mn/EVA has the intumescent char layer and the compact metal oxide layer. Therefore, S-NiMgAl-Mn/EVA shows the lowest pk-HRR and the longest pk-HRR time among all the composites. [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]

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]

This article presents a novel study on electrochemical codeposition of Mg-Li-Ce-La alloys on a molybdenum in LiCl-KCl-MgCl-KF melts containing RE(CO) (rich in cerium) at a temperature range of 953 K to 1073 K (680 °C to 800 °C). The cyclic voltammetry proved the feasibility of the production of the alloys. The factors that affect the current efficiency were investigated. The optimal electrolytic temperature and cathodic current density was 1023 K (750 °C) and 15.9 A·cm, respectively. The chemical content, phases, morphology, and distribution of alloy elements were analyzed by inductively coupled plasma mass spectrometry, X-ray diffraction, and scanning electron microscopy, respectively. The intermetallic compounds between Mg and Ce (La) distribute in the grain boundary of the alloys, present as reticulate structures, and refine the grains. [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]

To improve wettability between electrode material and electrolyte for high-rate supercapacitor application, the surfaces of graphite nanoplatelets (GNPs) were chemically modified by concentrated acids. The functional groups were confirmed by Fourier transform infrared spectra (FTIR) and zeta potential measurement. The microstructures and morphology of composites were characterized by X-ray diffraction (XRD) and scanning electron microscopy (SEM). Electrochemical properties of the composites were characterized by cyclic voltammograms (CV), galvanostatic charge/discharge and electrochemical impedance spectroscopy (EIS). At high discharge rates, the increase of specific capacitance of electrode material was primarily attributed to the improvement in wettability between electrode material and electrolyte, which came from the attached hydrophilic functional groups, resulting in rapid proton transport and more ion-accessible surface area. [ABSTRACT FROM AUTHOR]

In this paper, a new design paradigm referred to as compressive acquisition CMOS image sensors is introduced. The idea consists of compressing the data within each pixel prior to storage, and hence, reducing the size of the memory required for digital pixel sensor. The proposed compression algorithm uses a block-based differential coding scheme in which differential values are captured and quantized online. A time-domain encoding scheme is used in our CMOS image sensor in which the brightest pixel within each block fires first and is selected as the reference pixel. The differential values between subsequent pixels and the reference within each block are calculated and quantized, using a reduced number of bits as their dynamic range is compressed. The proposed scheme enables reduced error accumulation as full precision is used at the start of each block, while also enabling reduced memory requirement, and hence, enabling significant silicon area saving. A mathematical model is derived to analyze the performance of the algorithm. Experimental results on a field-programmable gate-array (FPGA) platform illustrate that the proposed algorithm enables more than 50% memory saving at a peak signal-to-noise ratio level of 30 dB with 1.5 bit per pixel. [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]

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]

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]

Novel magnetic hydrotalcite-like compounds (HTLcs) were synthesized through introducing magnetic substrates (Fe3O4) into the Co–Al HTLcs materials by hydrothermal method. The magnetic Co–Al HTLcs with different Fe3O4 contents were characterized in detail by XRD, FT-IR, SEM, TEM, DSC, and VSM techniques. It has been found that the magnetic substrates were incorporated with HTLcs successfully, although the addition of Fe3O4 might hinder the growth rate of the crystal nucleus. The morphology of the samples showed the relatively uniform hexagonal platelet-like sheets. The grain boundaries were well defined with narrow size distribution. Moreover, the Co–Al HTLcs doped with magnetic substrates presented the paramagnetic property. [ABSTRACT FROM AUTHOR]

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]

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]

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]

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 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]

This work presents a novel study on electrochemical preparation of Mg-Li-Yb alloys at a magnesium electrode in LiCl-KCl-YbCl3 melts at 743 K. Cyclic voltammograms showed that the reduction of ytterbium(III) ions is a stepwise reaction. The codeposition of Yb and Li takes place at magnesium electrode when the current intensity exceeds 60 mA in LiCl-KCl melts containing 2 wt % YbCl3. α, α + β, and β phases. Mg-Li-Yb alloys with different lithium contents were obtained by potentiostatic electrolysis at a magnesium electrode from LiCl-KCl melts with different concentrations YbCl3. [ABSTRACT FROM AUTHOR]