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Ionogels combine the advantages of gel polymers and ionic liquids (ILs), and not only have high ionic conductivity but also have favorable flexibility and are suitable for wearable electroluminescent devices. Aiming at solving the problems of low conductivity, low transmittance and poor tensile properties of conductive hydrogels, a new ionogel with attractive properties is presented. The results show that 1-ethyl-3-methylimidazolium chloride (EmimCl) incorporated in polyvinyl alcohol (PVA) not only improves the conductivity of the gel as an ion providing agent, but also improves the mobility and self-healing rate of the polymer chain as a plasticizer. When the EmimCl content is 100 wt%, the ionogel has an ionic conductivity of 3.4 × 10−3 S cm−1, an elongation at break value of 240%, and a light transmission of 94%. Based on the favorable flexibility, conductivity and light transmission of ionogels (PBE), flexible electroluminescent devices have been prepared with sandwich structures. The tested devices simultaneously exhibit high flexibility, high stability and considerable luminous intensity (3 V input, 114 cd m−2, drive assist 50 V, 400 Hz), showing their potential application in the field of wearable devices. [ABSTRACT FROM AUTHOR]

CsPbI3 has the least chemical stability among the CsPbX3 (X = Cl, Br, and I) perovskite nanocrystal (PNC) family due to its thermodynamically metastable characteristics, thus limiting the development of all-inorganic perovskite white-light devices. The current study presents a microfluidic-based continuous large-scale fabrication of CsPbI3-mesoporous SiO2 (CPI/m-SiO2) nanocomposites to solve the problem of large-scale continuous production of stable, repeatable, high-quality perovskite NCs. The results reveal that the chemical stability and thermal quenching behaviour of CPI PNCs were greatly improved due to the protection of mesoporous silica. Particularly, the water resistance property of CPI/m-SiO2 nanocomposites improved two-fold compared to that of noncomposite CPI PNCs, and the thermal stability of the CPI/m-SiO2 nanocomposites improved nearly three-fold at 373 K when compared with that of the noncomposite CPI NCs. Furthermore, photons were speculated to transmit along with the pores and channel structure of m-SiO2 to reduce photon absorption between NCs. Moreover, the microfluidic technology can operate continuously and is precisely controllable, enabling large-scale nanocomposite synthesis with uniform size and shape. [ABSTRACT FROM AUTHOR]

Macrophages are essential in innate immunity and are involved in a variety of biological functions. Due to high plasticity, macrophages are polarized in different phenotypes depending on different microenvironments to perform specific functions. Although many studies have focused on macrophage polarization, few have explored the polarization characteristics of macrophages at the subcellular level, even at nanoscale resolution. Here, we utilize AFM-based infrared spectroscopy (AFM-IR) to investigate the influence of an inducer on the expressed proteins of M1/M2 macrophages (induced by LPS and IL-13, respectively). The results from AFM-IR combined with principal component analysis revealed that the characteristic proteins within M1 contain about 35% antiparallel β-sheets (due to the high expression of TNF-α), while the proteins within M2 are made up of approximately 38.8% α-helices. The corresponding nanoscale chemical mapping demonstrates a remarkably heterogeneous distribution of expressed proteins inside single macrophages. Beside the biochemical properties, the biomechanical properties of macrophages were found to be softened in response to the polarization process. [ABSTRACT FROM AUTHOR]

A lead-free piezoelectric ceramic library of (1 − x − y)Bi0.5Na0.5TiO3–xBaTiO3–yK0.5Na0.5NbO3 [100(1 − x − y)BNT–100xBT–100yKNN] (0 ≤ x ≤ 0.12, 0 ≤ y ≤ 0.12) with 91 samples was prepared by using a high-throughput (HT) method. By comparing the performance mapping of Pr, Ec, TF–R, d33, d33* and the domain configuration to the compositions, the property diagram of the ternary library could be identified with three regions of (I) rhombohedral ferroelectric, (II) relaxor ferroelectric and (III) tetragonal ferroelectric phases. Remarkable phase-boundary effects were observed between two adjacent regions with phase coexistence features. Interestingly, the maximum d33 value was obtained near the I–III region boundary, while the maximum d33* value was obtained on the I–II region boundary. The electric field-induced rhombohedral–tetragonal phase transition at the I–III region boundary brings good piezoelectric properties. The reversible relaxor–ferroelectric phase transition near the I–II region boundary could be the origin of the enhanced depolarization effect of the samples with the recovery of the electric field, leading to high d33* values. [ABSTRACT FROM AUTHOR]

A low power (∼10 W), miniaturized atmospheric pressure glow discharge (APGD) source sustained between a tungsten cathode and a titanium tube anode was coupled with a hydride generation (HG) system for sensitive determination of antimony in water samples with atomic emission spectrometry (AES). Sb ions were converted into volatile hydrides through the reaction with KBH4 firstly and then were introduced into the APGD source for excitation and detected using a compact CCD (charge-coupled device) microspectrometer. A univariate approach was used to achieve optimized conditions and derive analytical figures of merit. Under optimal conditions, the limits of detection and quantification for Sb were 0.14 and 0.5 μg L−1, respectively. Moreover, the HG-APGD-AES system offered good repeatability (relative standard deviation ＜ 1.5%). The calibration curve was linear in the range between 0.5 and 100 μg L−1, with a correlation coefficient of R2 = 0.9996. The proposed method was successfully applied to the determination of certified reference materials (GSB 07-1376-2001, GBW07305a, GBW07307a and GBW073066) and some groundwater samples. Recoveries of Sb added to these water samples were within 90.9–100.7%, proving the good accuracy of the HG-APGD-AES method. [ABSTRACT FROM AUTHOR]

Based on a novel green dielectric barrier discharge plasma induced chemical vapor generation (DBD plasma-CVG), an on-line hyphenation of high performance liquid chromatography (HPLC) with atomic fluorescence spectrometry (AFS) was developed for the speciation of inorganic mercury (Hg2+), methylmercury (MeHg) and ethylmercury (EtHg). Without the use of other chemical reagents, the decomposition of organic mercury species and the reduction of Hg2+ could be completed in one step with the DBD plasma-CVG system. The operating parameters of DBD plasma-CVG and HPLC were optimized. Separation of mercury species was accomplished in less than 14 min on a ZORBAX SB-C18 separation column with a mobile phase containing 0.01% (v/v) 2-mercaptoethanol, 10% (v/v) methanol and 0.06 mol L−1 NH4Ac at pH 6.8. The limits of detection of the method were found to be 1.6, 0.42 and 0.75 μg L−1 for Hg2+, MeHg and EtHg, respectively. The developed method was validated by determination of the main analytical figures of merit and applied to the analysis of the certified reference material GBW10029 (tuna fish). The on-line interfacing of HPLC with DBD plasma-CVG-AFS for the speciation of mercury is simple, environmentally friendly, and represents an attractive alternative to the conventional tetrahydroborate interface system. [ABSTRACT FROM AUTHOR]

Double perovskites LaSrCoFeO6−δ (LSCF) and LaSrCoFeO6−δ with a three-dimensionally ordered macroporous structure (3DOM-LSCF) were successfully synthesized by a facile combustion process. Their crystal structure, morphology, BET surface area, band gap and catalytic properties were characterized in detail. Phase pure double perovskites LSCF and 3DOM-LSCF can be obtained by calcination at 550–950 °C for 4 h. The ordered and interconnected pore structure generated by using a PMMA template can be maintained successfully in the 3DOM-LSCF catalyst. Both catalysts had good catalytic performance in either CH4 selectivity or total yield. Production of CH4 from CO2 and H2O can reach 351.32 μmol g−1 for LSCF and 557.88 μmol g−1 for 3DOM-LSCF under photothermal conditions (350 °C + vis-light) in 8 h. The high solar-to-methane (STM) energy conversion efficiency was 1.217% for LSCF and 1.933% for 3DOM-LSCF in the photothermal mode. The results also show that the yield of CH4 in the photothermal mode is 5 times that in the thermal reduction mode. The double perovskites LSCF and 3DOM-LSCF are promising catalytic materials for the photothermal reduction of CO2 to hydrocarbon fuels. [ABSTRACT FROM AUTHOR]

A series of mesoporous WO3 catalysts were facilely synthesized by a hydrothermal method using mesoporous silica KIT-6 as a hard template and silicotungstic acid as a precursor. All the catalysts possess a well-defined mesoporous structure with interconnected networks. Oxygen-deficient mesoporous WO3 (m-WO3−x) was prepared by hydrogenation treatment at different temperatures with improved photothermal coupling performance. Moreover, the as-prepared catalysts exhibit selectivity toward CH4 evolution under visible-light only irradiation. Then, under photothermal conditions, the results show that the concentration of oxygen vacancies of m-WO3 has a great influence on its catalytic performance. The CH4 evolution rate reached 25.77 μmol g−1, which is about 22 times that of mesoporous WO3 (1.17 μmol g−1) under the same conditions, and a moderate concentration of oxygen vacancies is necessary to achieve selectivity for the conversion of CO2 into CH4. A mechanism of the catalytic reduction of CO2 over m-WO3−x is proposed, in which the initial oxygen vacancies function as an excellent electron transfer mediator and decompose CO2 into its elements (C/CO). These findings may further broaden the scope for photothermal chemical conversion and provide new insights into the oxygen nonstoichiometry strategy for the development of CO2 reduction. [ABSTRACT FROM AUTHOR]

An elastic, structurally colored fiber with reversible structural color is described in this article. Using an external magnetic field, Fe3O4@C superparamagnetic colloidal nanocrystal clusters (SCNCs) formed one-dimensional chain-like photonic crystal structures and were embedded in a polyacrylamide matrix. When the fiber was stretched/squeezed in the horizontal direction, the size of the fiber reduced/increased in the vertical direction. As a result, the distance between each sphere in chain-like structures can be reversibly changed through the elastic deformation of the matrix, and the structurally colored fiber displays brilliant colors, ranging from red to green as the mechanical strain changes, which can be clearly observed by the naked eye. The reflection peak can be tuned from 637 nm to 515 nm as a function of fiber extrusion or elongation. The novel structurally colored fiber is expected to have some important applications such as the substitution of some fiber-based wearable electronic strain sensors because this fiber does not require any additional devices to provide energy. [ABSTRACT FROM AUTHOR]

Direct determination of thiomersal in vaccine by atomic fluorescence spectrometry with dielectric barrier discharge (DBD)-plasma induced vaporization was developed. No sample pretreatments other than dilution were needed in the measurement. The evaporation and atomization of thiomersal in vaccine samples was achieved rapidly in one step. The produced mercury vapor was transported to atomic fluorescence spectrometry for analysis. It is a green method that obviates the need of strong oxidization procedure for degradation of thiomersal to inorganic mercury and reduction agents such as sodium tetrahydroborate(iii) or tin(ii) chloride to generate Hg vapor. The DBD plasma was generated in a quartz tube (i.d. 5 mm and o.d. 6 mm) by a concentric circles model. The operating parameters such as discharge gas type, gas flow rate, and power were optimized. Possible interference by concomitant elements was also investigated. External calibration was achieved with aqueous standards solution of thiomersal. Under the optimal experimental condition, the detection limit was 0.03 μg L−1 for Hg, equivalent to 0.06 μg L−1 of thiomersal in solution. The analytical precision, represented by the relative standard deviation (RSD) from multiple measurements (n = 5) of 5 μg L−1 thiomersal (as Hg), was 2.5%. This method was also applied to measure thiomersal in five commercial vaccines. In the absence of CRMs for thiomersal in vaccine samples, it was validated by comparing with results from inductively coupled plasma mass spectroscopy (ICP-MS), which showed good correlation. [ABSTRACT FROM AUTHOR]

An atmospheric pressure plasma sustained by an alternating-current power supply was generated using the electrolyte solution as one electrode. The emission spectra of the plasma are related to the metal ions present in the solution and thus can be used for metal ion detection. The main advantage of this source is that it operates at low flow rates in the range of 0.1 to 0.8 mL/min. The effects of the discharge electrolyte anion, the pH and solution flow rate on emission signal were studied. The analytical response curves for Na and Cd demonstrated good linearity at least in the range of 0.5–100 mg L−1. The limit of detection of Na and Cd were determined to be 0.04 and 0.09 mg L−1, respectively. The method was applied for the determination of elements in simulated natural water samples (GBW(E)080408 and GBW(E)080402). The obtained results were in good agreement with the reference values. It provides an alternative analytical method for the determination of elements in water samples. [ABSTRACT FROM AUTHOR]

Structural colored fiber was fabricated by an isothermal heating evaporation-induced self-assembly method. Under ambient white light illumination, the fibers appear colored due to optical reflectance, which is determined by the lattice constants of the photonic crystals. By controlling the size and layers of the silica nanospheres, the fiber color can be changed., (This journal is © The Royal Society of Chemistry 2011)

This paper describes a low-temperature dielectric barrier discharge (DBD)-plasma induced vaporization technique using mercury as a model analyte. The evaporation and atomization of dissolved mercury species in the sample solution can be achieved rapidly in one step, allowing mercury to be directly detected by atomic fluorescence spectrometry. The DBD plasma was generated concentrically in-between two quartz tube (outer tube: i.d. 5 mm and o.d. 6 mm, inner tube: i.d. 2 mm and o.d. 3 mm). A copper electrode was embedded inside the inner quartz tube and sample solution was applied onto the outer surface of the inner tube. The effects of operating parameters such as plasma power, plasma gas identity, plasma gas flow rate and interferences from concomitant elements have been investigated. The difference in the sensitivities of Hg(2+), methylmercury (MeHg) and ethylmercury (EtHg) was found to be negligible in the presence of formic acid (≥1% v/v). The analytical performance of the present technique was evaluated under optimized conditions. The limits of detection were calculated to be 0.02 ng mL(-1) for Hg(2+), MeHg and EtHg, and repeatability was 6.2%, 4.9% and 4.3% RSD (n = 11) for 1 ng mL(-1) of Hg(2+), MeHg and EtHg, respectively. This provides a simple mercury detection method for small-volume samples with an absolute limit of detection at femtogram level. The accuracy of the system was verified by the determination of mercury in reference materials including freeze-dried urine ZK020-2, simulated water matrix reference material GBW(E) 080392 and tuna fish GBW10029, and the concentration of mercury determined by the present method agreed well with the reference values.

Single crystalline zinc stannate (Zn(2)SnO(4) and ZnSnO(3)) nanoparticles were synthesized by a simple one-step hydrothermal reaction with a high production yield. Zn(2)SnO(4) is a (111) face-exposed octahedron, whereas ZnSnO(3) is a (100) face-exposed hexahedron structure. In particular, Zn(2)SnO(4) exhibits an efficient performance for applications in dye-sensitized solar cells.

The WO(3)/ITO/CaFe(2)O(4) film surface showed visible-light induced superhydrophilicity, which is ascribed to efficient charge separation, resulting from the recombination of photo-electrons from WO(3) with photo-holes from CaFe(2)O(4) in the ITO layer.