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Two cyan-emitting phosphors with different bandwidths were successfully synthesized through the high-temperature solid-state method in a reducing atmosphere. The crystal structures, morphologies, and luminescence properties of the as-prepared phosphors were investigated. The Rietveld refinements of the powder X-ray diffraction (XRD) data demonstrated the single phase of the samples, and two crystallographic sites of La3+ were observed in the crystal structure. Under the excitation of UV light, both Ba0.45Ca2.5La6(SiO4)6: 0.05 Eu2+ and Ba1.45Ca1.5La6(SiO4)6: 0.05 Eu2+ phosphors emitted cyan light due to the 4f65 d1→4f7 transitions of the Eu2+ ion. The emission spectra could be well fitted by two component Gaussian peaks corresponding to two different coordination environments of the Eu2+ ions. The temperature-dependent photoluminescence spectra show a large difference on the thermal stability between the two phosphors. The two phosphors exhibit effective absorption of near-UV light and their internal quantum efficiencies (IQEs) were calculated as 31.5% and 42.4% under 295 nm UV-light excitation. The experimental results indicate that the novel cyan phosphors might have potential applications in white light-emitting diodes (LEDs) based on the near-UV LED chip.

The hydrophobicity of ultrafiltration membranes is the main cause of membrane fouling and reduced permeability, so it is necessary to improve the hydrophilicity and anti-fouling performance of ultrafiltration membrane materials. MoS2 nanoparticles that were modified with polydopamine (PDA) and polyethyleneimine (PEI), named MoS2-PDA-PEI, were added to fabricate a polyethersulfone ultrafiltration membrane (PES/MoS2-PDA-PEI) for the first time. The effects of modified MoS2 nanoparticles on membrane performance were clarified. The results indicated that the permeability, rejection, and anti-fouling capability of the hybrid PES/MoS2-PDA-PEI membrane have been improved compared with the pristine PES membrane. When the content of MoS2-PDA-PEI nanoparticles in the membrane is 0.5%, the pure water flux of the hybrid membrane reaches 364.03 L m−2 h−1, and the rejection rate of bovine serum albumin (BSA) and humic acid (HA) is 96.5% and 93.2% respectively. The flux recovery rate of HA reached 97.06%. As expected, the addition of MoS2-PDA-PEI nanoparticles promotes the formation of the porous structure and improves the hydrophilicity of the membrane, thereby improving its antifouling performance.

Innovative syntheses of uniform and size-controlled chlorapatite crystals need to be developed. Molten salt synthesis is a simple process, which uses low temperatures and short reaction times to obtain synthesized powders with uniform chemical composition as well as good crystal morphology and high-phase purity. In this study, a molten salt synthesis was used to prepare ClAP microcrystallites at different temperatures, reaction times, and quantities of molten salt. ClAP microcrystallites with different sizes and morphologies were obtained, and the process parameters were optimized. The phase formation and morphologies of the ClAP microcrystallites were examined by X-ray powder diffraction and scanning electron microscopy. The results determined the optimal parameters, as follows: synthesis temperature, 600 °C; reaction time, 4 h; and ClAP/molten salt ratio, 1 : 3. The reaction time and the quantity of the molten salt, as well as the growth mechanism of the ClAP microcrystallites, were proposed based on the phase formation and morphologies of ClAP synthesized at various temperatures. ClAP phosphors activated using different ions (Sb3+, Eu2+, and Tb3+) were prepared by the molten salt method at 600 °C for 4 h with a ClAP/salt ratio of 1 : 3. The as-prepared ClAP:Sb3+/Eu2+/Tb3+ phosphors exhibited a blue-green emission (470 nm), a blue emission (460 nm), and a green emission (547 nm). Their excellent photoluminescence properties indicated their potential for application in white light emitting diodes.

Sensitive and selective detection of harmful gas is an important task in environmental monitoring. In this work, a gas sensor based on cataluminescence (CTL) for detection of acetaldehyde was designed by using nano-NiO as the sensing material. The sensor shows sensitive response to acetaldehyde at a relatively low working temperature of 200 &deg, C. The linear range of CTL intensity versus acetaldehyde concentration is 0.02&ndash, 2.5 mg/L, with a limit of detection of 0.006 mg/L at a signal-to-noise ratio of three. Mechanism study shows that electronically excited CO2 is the excited intermediate for CTL emission during the catalytic oxidation of acetaldehyde on the NiO surface. The proposed sensor has promising application in monitoring acetaldehyde in residential buildings and in the workplace.

The Zn1–xAl2O4:xEu2+ phosphor powders were synthesized by the solid-state reaction method. The synthesis temperature for ZnAl2O4 was optimized, whereas the phase structure, TEM images, photoluminescence (PL) properties, the concentration quenching mechanism, the fluorescence decay curves, as well as the CIE chromaticity coordinates of the samples were investigated in details. Under the excitation at 379 nm, the phosphor exhibits an asymmetric broad-band green emission with a peak at 532 nm, which is ascribed to the 5d–4f transition of Eu2+. When the doping concentration of Eu2+ ions is 0.01, the luminescence intensity of the sample reaches the maximum value. It is further proved that the exchange interaction results in the concentration quenching of Eu2+ in the Zn1–xAl2O4:xEu2+ phosphor powders. The thermal quenching property of ZnAl2O4:Eu2+ phosphor was investigated and the quantum efficiency (QE) values of the selected Zn0.99Al2O4:0.01Eu2+ phosphor was measured and determined as 54.85%. The lifetime of the optimized sample Zn0.99Al2O4:0.01Eu2+ is 3.0852 μs and the CIE coordinate of the sample was calculated as (0.3323, 0.5538) with high-color-purity green emission. All properties indicate that the green-emitting ZnAl2O4:Eu2+ phosphor powder has potential application in white LEDs.

It is highly desirable to red shift the emission of Y3Al5O12:Ce3+ phosphor to obtain a warmer correlated color temperature (CCT) in applications for blue-light pumped white-light emitting diodes (w...

A mercury(II) ion-selective electrode with an ionic liquid (IL), 1-methyl-2-butylthioimidazolium bis(trifluoromethanesulphonyl)imide ([C1C4Sim]NTf2) as active material was constructed. Parameters affecting the performance of the electrodes such as the dosages of the IL and carbon nanotubes and the aqueous pH values were investigated. Experimental results indicated that the optimal composition of the electrode filling material was 47.6% [C1C4Sim]NTf2, 47.6% tetrabutylphosphonium bis(trifluoromethanesulphonyl)imide (TBPNTf2) and 4.8% carboxylic multi-walled carbon nanotubes (MWCNTs-COOH). Under the selected conditions, the proposed electrodes showed a good linear response in the concentration range of 10−10–10−5 mol L−1 and had a detection limit of 4.1 × 10−11 mol L−1. No great interference from common metal ions was found. The proposed electrodes were applied to determine Hg2+ in seafood samples; the results were comparable to those of the direct mercury analyzer. Keywords: Ionic liquids (ILs), Mercury, Ion-selective electrodes, Carbon nanotubes, Seafood

Purpose The purpose of this paper is to design and fabricate a three-dimensional (3D) bionic airflow sensing array made of two multi-electrode piezoelectric metal-core fibers (MPMFs), inspired by the structure of a cricket’s highly sensitive airflow receptor (consisting of two cerci). Design/methodology/approach A metal core was positioned at the center of an MPMF and surrounded by a hollow piezoceramic cylinder. Four thin metal films were spray-coated symmetrically on the surface of the fiber that could be used as two pairs of sensor electrodes. Findings In 3D space, four output signals of the two MPMFs arrays can form three “8”-shaped spheres. Similarly, the sensing signals for the same airflow are located on a spherical surface. Originality/value Two MPMF arrays are sufficient to detect the speed and direction of airflow in all three dimensions.

As one of the most complicated joint structures, temporomandibular joint (TMJ) is susceptible to inflammatory reaction caused by osteoarthritis, rheumatoid arthritis and so on. The treatment for TMJ inflammation is still challenging due to the rapid clearance and lack of selectivity of traditional medication. Herein, we design a novel discrete sulfonylcalix[4]arene-based magnesium(II) coordination container, MgDHIA, which features satisfactory biocompatibility, appropriate molecular size and multiple binding domains. MgDHIA is capable of selectively encapsulating rapamycin (RAPA) in the endo cavity and folic acid (FA) in the exo cavities to form the co-loaded system RAPA-FA@MgDHIA, which exhibits outstanding activated macrophages targeting, stepwise releasing and cellular uptake behaviors. For therapeutic aspect, the RAPA-FA@MgDHIA reprograms the phenotype of polarized macrophages, specifically, transforming the pro-inflammatory M1 macrophages to anti-inflammatory M2 phenotype by inhibiting NF-kB pathway. The in vivo studies also demonstrate that the RAPA-FA@MgDHIA presents higher accumulation in inflamed synovial tissues, protecting the articular cartilage and subchondral bone structures by alleviating synovial inflammation. Anyway, we first evaluate the application of coordination container-based nanomedicine in treatment of inflammatory TMJ, demonstrating that the drug and targeting agents co-loaded coordination container remarkably boosts the therapeutic efficacy of traditional medication, thus providing a promising approach for anti-inflammatory treatment in joints.

Management of Marcellus Shale flowback water is a rising concern in Pennsylvania. Due to limited capacity for wastewater disposal by deep-well injection, flowback water reuse is the dominant management option in PA. Microfiltration is a promising technology to be used in a mobile treatment system for solids removal from Marcellus Shale flowback water prior to reuse. It was found previously that early Marcellus Shale flowback water could cause severe membrane fouling due to the presence of stable submicron colloids. Bench-scale cross-flow filtration system was used in this study to evaluate the feasibility of microfiltration for treatment of Marcellus Shale flowback water that does not contain these submicron colloids. The performance of alumina (Al 2 O 3 ) and silicon carbide (SiC) ceramic membranes that have distinct surface charge properties was evaluated in this system using a constant transmembrane pressure. The difference in the isoelectric point of these membranes suggested possible differences in fouling behavior, but extremely high salinity of the flowback water screened the electrostatic interactions and minimized these differences. For the two flowback waters tested in this study, the one with lower TDS caused more severe fouling of both SiC and Al 2 O 3 membranes during the first 15 min of filtration. The flux decline analysis revealed that intermediate pore blocking was the dominant fouling mechanism in the early filtration stage. Such behavior was due to the fact that the particulate matter in this flowback water was in the aggregate form and the flocs were prone to breakup at elevated shear stress caused by high pumping rate. Despite having much higher TSS, the other flowback water did not cause excessive membrane fouling due to stability and strength of its original particles.

In this work, the treatment of bio-treated coking wastewater (BCW) by catalytic ozonation was conducted in semi-batch and continuous flow reactors. The kinetics of chemical oxygen demand (COD) removal were analyzed using BCWs from five coking plants. An integral reactor with catalytic ozonation stacked by ozone absorption (IR) was developed, and its efficiency was studied. The catalyst of MnxCe1-xO2/&gamma, Al2O3 was efficient in the catalytic ozonation process for the treatment of various BCWs. The chemical oxygen demand (COD) removal efficiencies after 120 min reaction were 64&ndash, 74%. The overall apparent reaction rate constants were 0.0101&ndash, 0.0117 min&minus, 1, which has no obvious relationship with the initial COD of BCW and pre-treatment biological process. The IR demonstrated the highest efficiency due to the enhancement of mass transfer and the utilization efficiency of ozone. Bypass internal circulation can further improve the reactor efficiency. The optimal results were obtained with the ozone absorption section accounting for 19% of the valid water depth in the reactor and 250% of circulation flow ratio. The long-term and full-scale application of the novel reactor in a continuous mode indicated stable removal of COD and polycyclic aromatic hydrocarbons (PAHs). The results showed that the system of IR is a promising reactor type for tertiary treatment of coking wastewater by catalytic ozonation.

Acid-washed activated carbon (AC-A), nitric acid modified activated carbon (AC-NO2), aminated activated carbon (AC-NH2) and cerium-loaded activated carbon (Ce/AC) were prepared and characterized by BET procedure, Boehm titration and SEM. Their performances were investigated for the ozonation of p-chlorobenzoic acid (p-CBA) in its solution and organic compounds in reverse osmosis concentrate (ROC). Nitration and amination had little effect on the surface area of catalyst, but increased the concentration of surface acid and basic functional group respectively. After loading Ce, the surface area of the catalyst decreased, and amount of Ce particles were agglomerated on the surface of activated carbon. All the four catalysts can improve the removal rate of the organics in water. Among the four catalysts, Ce/AC shows the highest catalytic activity. The removal rates of p-CBA, TOC and three target pollutants (e.g., tetracycline, metoprolol, atrazine) are 99.6%, 70.38%, 97.76%, 96.21% and 96.03%, respectively. Hydroxyl radical (&middot, OH) was proved to be the core of catalytic reaction mechanism for Ce/AC, with the contribution rate to p-CBA removal of 91.4%. The surface groups and the Ce loaded on AC were the initiator for the rapid generation of &middot, OH. Electron transfer between electron-rich structures and cerium oxide might be a synergistic effect that can increase catalytic activity of Ce loaded on AC. Catalytic ozonation with Ce/AC is a promising ROC treatment technology due to its efficiency and possibilities for improvement.

Rare earth aluminate phosphors are well-known for being nontoxic and environmentally friendly. In this work, Tb3+-doped SrLaAlO4 phosphors were synthesized via a facile high temperature solid-state reaction method. The Optimum reaction temperature is determined to be 1300 °C based on the results of powder X-ray diffraction (XRD). The SEM patterns and TEM images correspond with the results of Rietveld refinement and show that the SrLa1-xAlO4:xTb3+ samples present a flaky structure. The results of photoluminescence spectrums (PL) show that SrLa1-xAlO4:xTb3+ phosphors can absorb in the UV–vis spectral region of 228 nm–263 nm and exhibit several emission peaks between 450 and 650 nm, and the highest peak was at 508 nm. The luminescence properties of SrLa1-xAlO4:xTb3+ have a strict dependence on the cation substitution levels. When the doping concentration of Tb3+ was 0.05, the emission intensity of the sample is strongest. The thermal quenching result of the SrLa0.95AlO4:0.05 Tb3+ phosphors shows that these phosphors are relatively sensitive to temperature changes under an excitation of 228 nm, as the temperature increases from 25 °C to 125 °C, the emission intensity (peak at 548 nm) decayed to 55.11% of that at room temperature. However, when the temperature increases to 125 °C, the emission intensity (peak at 548 nm) decayed to 61.16% of the initial value under an excitation of 263 nm, which showed a relatively good thermal stability. The internal quantum efficiency (QE) values of the SrLa0.95AlO4:0.05 Tb3+ phosphors was measured and determined to be 48%. Under excitations of 228 nm and 263 nm, the lifetimes of the optimized sample SrLa0.95AlO4:0.05 Tb3+ were 1.3986 ms and 1.2095 ms, respectively, and the CIE coordinates of the sample were calculated as (0.2971, 0.4981), (0.3056, 0.5329), respectively. Under both excitations SrLa0.95AlO4:0.05 Tb3+ exhibited high-color-purity green emission.

In this research, ordered silver nanowires (NWs) were transferred to flexible, freestanding nanofibrillated cellulose (NFC) thin film. Silver NWs were synthesized via a solution chemistry method and arranged by a novel assemble method at the oil–water–air, three phase interface. The transparent nanopaper was made of NFC through vacuum suction filtrated method. Then the arranged Ag NWs were transferred to the surface of the nanopaper using a relatively simple method to form a compound, nanopaper/Ag NWs. X-ray diffraction, Fourier transform infrared spectroscopy, field emission scanning electron microscopy, atomic force microscopy, and transmission electron microscope were taken to characterize the phase and the morphology of the as-prepared products. Characterization of the as-synthesized nanopaper/Ag NWs indicated that they were compounded physically and the Ag NWs were well crystalline. The as-synthesized nanopaper showed well translucency. The nanopaper/Ag NWs showed excellent flexibility and conductivity. The as-synthesized products have the potential application in flexible conductor. This study may provide an effective strategy to design and construct nano-metallic materials with multitudinous features and potential applications in electric devices sensors, flexible devices and conductive materials.