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The efforts to achieve sustainable chemical conversion and efficient CO 2 utilization are critical to addressing climate change and environmental sustainability, and therefore the development of effective CO 2 conversion catalysts is crucial. In this study, novel acid-base bifunctional catalysts, MIL-101-SO 3 H@Atz and MIL-101-SO 3 H@DAtz, were successfully synthesized using MIL-101-SO 3 H as an acid support material through post-synthetic modification with 3-amino-1,2,4-triazole (Atz) and 3,5-diamino-1,2,4-triazole (DAtz) for CO 2 conversion reaction. The incorporation of the amine species into MIL-101-SO 3 H created unique synergistic effects with dual acid-base catalytic sites, facilitating the efficient conversion of CO 2 and epoxides into cyclic carbonates. Among the catalysts, MIL-101- SO3H@DAtz demonstrated superior catalytic performance with achieving 100% epichlorohydrin (ECH) conversion with over 99% selectivity to cyclic carbonate with high selectivity of > 99% under the ambient condition of 1 bar CO 2 without any co-catalyst or solvent. The elucidated CO 2 cycloaddition reaction mechanism highlights the synergistic effects of acid-base functionalities and CO 2 -philic Lewis bases as well as hydrogen bonding donor groups, providing valuable insights into the factors contributing to superior catalytic performance. The simulated flue gas (15% CO 2 /85% N 2 , v/v) was also conducted using MIL-101-SO 3 H@DAtz catalyst. Additionally, the MIL-101-SO 3 H@DAtz catalyst exhibited remarkably robust structural stability and recyclability, maintaining its activity over multiple cycles. [Display omitted] • Design and synthesis of site-isolated Lewis acid-Brønsted base bifunctional MIL-101-SO 3 H@DAtz catalyst. • Excellent catalytic activity of MIL-101-SO 3 H@DAtz for CO 2 cycloaddition at ambient pressure without co-catalyst. • Accelerating epoxide ring-opening by the isolation of catalytic sites in a single catalyst system. • MIL-101-SO 3 H@DAtz showed high structural stability and reusability during ten cycles. • A plausible reaction mechanism for CO 2 -epoxide cycloaddition was proposed. [ABSTRACT FROM AUTHOR]

• Acid-base dual-functional ZIF-8 (ZIF8-A61-SO 3 H) was prepared via post-synthetic modification. • ZIF8-A61-SO 3 H catalyst showed high catalytic performance in one-pot tandem deactalization-Knoevenagel condensation reaction. • Catalytic activity of ZIF8-A61-SO 3 H was compared with ZIF-8 and amine-functionalized ZIF-8 catalysts. • A plausible catalytic reaction mechanism was proposed. An acid-base bifunctional zeolitic imidazolate framework catalyst (ZIF8-A61-SO 3 H) with amine and sulfonic acid groups was successfully prepared through simple two step post-synthetic modification: preparation of amine-functionalized ZIF-8 with amine contents of 61% (ZIF8-A61) by the ligand exchange of 2-mIM with 3-amino-1,2,4-triazole (Atz), followed by the sulfonic acid functionalization by the ring-opening reaction of 1,3-propanesultone with –NH 2 groups in ZIF8-A61. Amine-functionalized ZIF8-A materials with difference amine contents (15%, 34%, and 61%, respectively) were also prepared by controlling the synthesis time. All obtained ZIF catalysts evaluated as a heterogeneous catalyst for one-pot deacetalization-Knoevenagel condensation tandem reaction. Compared with ZIF-8 and amine-functionalized ZIF-8 catalysts, ZIF8-A61-SO 3 H catalyst showed good catalytic performance with 100% conversion of the reactant and 98% selectivity of the final Knoevenagel product. An enhanced catalytic activity can be attributed to the co-existence of site-isolated acid-base groups on the ZIF8-A61-SO 3 H catalyst in close proximity. The heterogeneous nature of the catalytic system was confirmed by a hot-filtering test and the catalyst also exhibited reusable in the five repeated cycles. A plausible catalytic mechanism of deacetalization-Knoevenagel condensation reaction over ZIF8-A61-SO 3 H was also proposed. [ABSTRACT FROM AUTHOR]

Abstract In this paper, we demonstrate highly conductive and stretchable fiber interconnections for electronic textiles (e-textiles) using dry-spun carbon nanotube (CNT) fibers modified with ionic liquid (IL)/poly (vinylidene fluoride- co -hexafluoropropylene) (PVDF-HFP) copolymer composite. By adopting direct infiltration of CNT fibers with a mixture of 1-butyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide and PVDF-HFP, mechanical properties such as stretchability, maximum load and strain were significantly improved while minimizing the reduction in electrical conductivity. Such IL/PVDF modified CNT fibers (hybrid CNT fibers) exhibited electrical conductivity up to ∼1300 S/cm, with maximum load and strain values of 0.84 N and 35.7%, respectively. Using hybrid-CNT fibers, we demonstrated highly stretchable and electrically stable fiber interconnections for e-textiles by optimizing the interconnection pattern design. Particularly, by adopting a serpentine pattern, stretchability up to ∼70% and resistance variation of ∼2.7% at a tensile strain of 40% were achieved. [ABSTRACT FROM AUTHOR]

Graphical abstract Adsorption of volatile organic compounds (VOCs) over MIL-125-NH 2 was investigated by measuring their adsorption isotherms. Significant amounts of the VOCs were adsorbed, and their adsorption capacities followed the order of increasing polarity. Abstract Volatile organic compounds (VOCs) cause environmental and health problems by forming photochemistry smog, and development of an effective adsorbent for their removal is important. In this work, adsorption of a series of selected VOCs over an amine-functionalized metal organic framework, MIL-125-NH 2 , was investigated by measuring their adsorption isotherms at three different temperatures. Significant amounts of the VOCs were adsorbed, and their adsorption capacities increased with the increasing order of polarity (p -xylene < toluene < benzene < acetone < isopropanol). In addition, formaldehyde breakthrough capacities were measured and MIL-125-NH 2 , exhibited a clearly superior performance to other MOFs, probably because of the synergistic effects provided by the amine groups that strongly interacting with the formaldehyde and the small micropores in MIL-125-NH 2. [ABSTRACT FROM AUTHOR]

Mesoporous silica SBA-15 grafted with benzene-1,3,5-triamido-tetraphosphonic acid (SBA-15-BTATPA) was synthesized. After detailed characterization of the material using various analytical instrumentation, it was applied for the recovery of Nd 3+ as a function of the contact time, ion concentration, and pH. The adsorption equilibria and kinetics were also examined. Under the optimal conditions, adsorption equilibrium was reached within 60 min of contact time, and the adsorption capacity of Nd 3+ at room temperature and pH 6 was 129.8 mg g −1 , which was higher than that by other rare earth element (REE) ions tested for comparison (Y 3+ , La 3+ , and Ce 3+ ). The adsorbent showed excellent distribution coefficient for Nd 3+ greater than 1.0 × 10 5 mL/g. The preferential order of adsorption in the ion mixture with equal ion concentrations was Y 3+ >Nd 3+ >Ce 3+ >La 3+ , which followed the sequence of their decreasing atomic size and increasing stability constant. The competing adsorption by transition metal ions, such as Cu 2+ , Ni 2+ , Co 2+ , and Zn 2+ , on the REEs recovery was negligible (<2%). The observed adsorption isotherms could be fitted well to a Langmuir model (correlation factor R 2 > 0.99), whereas the adsorption kinetics could be described satisfactorily by a pseudo second order kinetic model. The material was reusable for up to 5 consecutive times with only a slight decrease in adsorption capacity. [ABSTRACT FROM AUTHOR]

A P300 speller is a device for typing words by analysing the electroencephalogram (EEG) caused by visual stimuli. Among classifying methods used for the P300 speller, the ensemble of support vector machines (eSVM) is well known for achieving considerable classification accuracy. The eSVM is composed of linear support vector machines trained by each small part of the divided training data. To obtain an ensemble model with good accuracy, it is generally important that each classifier be as accurate and diverse as possible; diverse classifiers have different errors on a dataset. However, the conventional eSVM considers only an accuracy viewpoint of an individual classifier by clustering the homogeneous training data with similar noisy components. With such a viewpoint of diversity, we propose a dataset manipulation method to divide a training dataset into several groups with different characteristics for training each classifier. We reveal that the distance between a letter on which a subject is concentrating, and an intensified line on a visual keyboard, can generate EEG signals with different characteristics in a P300 speller. Based on this property, we partition the training data into groups with the same distance. If each individual SVM is trained using each of these groups, the trained classifiers have the increased diversity. The experimental results of a P300 speller show that the proposed eSVM with higher diversity improves the letter typing speed of the P300 speller. Specifically, the proposed method shows an average of 70% accuracy (verbal communication with the Language Support Program is possible at that level) by repeating the dataset for a single letter only four times. [ABSTRACT FROM AUTHOR]

Size-controlled hybrid ZIFs (core-shell ZIF-67@ZIF-8, ZIF-8@ZIF-67, and bimetallic Zn/Co-ZIF-8) with the same particle size were synthesized by a seed-mediated methodology by adjusting the particle size of core ZIFs. The synthesized hybrid ZIFs was tested as heterogeneous catalysts for the CO 2 cycloaddition to epoxides using pure CO 2 gas and mixed gas (85 % CO 2 /15% N 2) without any co-catalyst and solvent. The effect of the composition of shell and core ZIFs on the catalytic performance of CO 2 cycloaddition reaction to epoxides were investigated. Furthermore, the correlation between structural defects and catalytic activity in ZIF catalysts along with their particle sizes was investigated by calculating the ratio of DXRD/DSEM. Both core-shell type ZIF-67@ZIF-8 and ZIF-8@ZIF-67 exhibited better catalyst performance of CO 2 cycloaddition reaction than other ZIF catalysts. Among the ZIF catalysts, ZIF-67@ZIF-8 exhibited the highest catalytic performance for epoxide conversion owing to its abundant Lewis acid-base properties and relatively large window size of ZIF-8 shell with appropriate binding force between epoxide and CO 2. It showed good recyclability for CO 2 cycloaddition reaction without a structural collapse during ten recycles. The structural stability of ZIF-67@ZIF-8 was examined in detail by a hot filtering test, leaching test, and TGA analysis. The mechanism of CO 2 cycloaddition reaction was proposed and the effect of the shell composition in core-shell type ZIFs on the binding energy with epoxide substrate also was studied based on DFT calculations. [Display omitted] • Synthesis of size-controlled core-shell ZIFs by a seed-mediated methodology. • Investigating the effect of the core-shell ZIF structures on the catalytic activity. • ZIF-67@ZIF-8 exhibits high catalytic activity for CO 2 cycloaddition reaction. • The correlation between structural defects and catalytic activity in ZIF catalysts. • Calculation of binding energy with epoxide and core-shell ZIFs using DFT method. [ABSTRACT FROM AUTHOR]

Two porous aromatic polymers incorporated with carbonyl-functionality (CBAP-1 and CBAP-2) were synthesized via a Friedel-Crafts benzoylation reaction between 1,3,5-triphenylbenzene/biphenyl and terephthaloyl chloride/1,3,5-benzenetricarbonyl trichloride in the presence of anhydrous AlCl 3 as catalyst, and post-synthetically functionalized with ethylenediamine to obtain CBAP-1(EDA) and CBAP-2(EDA). The microporous carbon materials with BET surface areas up to 1063 m 2 g −1 were also prepared by carbonization of CBAP-1 and CBAP-1(EDA). After characterization using various analytical methods, these materials were tested as adsorbents for CO 2 and CH 4 capture at ambient conditions. High CO 2 /N 2 (97.2 and 87.8) and CO 2 /CH 4 (24.3 and 22.3) selectivities were observed for CBAP-1(EDA) and CBAP-2(EDA), respectively, at 273 K/1 bar, whereas the carbonized microporous materials exhibited high adsorption capacities for CO 2 (216.0–231.6 mg g −1 ) and CH 4 (36.6–38.1 mg g −1 ). This work demonstrates that post-synthesis functionalization of a porous aromatic polymer prepared by the simple Friedel-Crafts reaction can be an effective means to produce a family of host materials for effective gas adsorption. [ABSTRACT FROM AUTHOR]

Large quantities of fly ash are discharged as a by-product from coal power plants. Therefore, an effective method to recycle this waste material is necessary. In this regard, the high silica content of fly ash makes it a potential useful source for the synthesis of nanoporous materials, such as zeolites, mesoporous silica or silica aerogels. In this mini review, zeolite synthesis from fly ash was examined by considering the ash composition, pretreatment procedures, and hydrothermal synthesis conditions (substrate composition and synthesis temperature/time) to identify an optimal set of synthesis conditions. These zeolites can be used as adsorbents and ion-exchangers for environmentally hazardous materials including those present in the fly ash itself. The synthesis of mesoporous silica materials with a high surface area and large pore volume derived from fly ash was next assessed for their use as a support and as a surface-functionalized host for capturing the global warming CO 2 and rare earth metal ions. Lastly, the utilization of fly ash for the preparation of silica aerogels or adiabatic foams, which are being considered as a potential building insulation materials, was briefly examined. Cases of synthesizing these nanoporous materials using other solid wastes as silica and/or alumina sources were also examined. The synthesis of diverse porous materials utilizing the waste sources would enable a high level of recycling for a sustainable society with a low environmental burden. [ABSTRACT FROM AUTHOR]

This study focuses on process modeling and simulation of a biomass fast pyrolysis system. For the simulation of the biomass fast pyrolysis process, two types of simulation models were developed: lumped model and hybrid model. Employing the above models, the effect of reaction temperature on reaction rate and final product yields were analyzed. It was found that the hybrid model exhibited a peculiar characteristic of displaying multiphase reacting flow occurring in fluidized bed. This behavior of hybrid model could have attributed for the difference in product yields of the models (hybrid and lumped). For the yields of the tar and NCG, hybrid model prediction was very consistent with the experimental results than the lumped model. However, for char yield, the results of both the lumped model and the hybrid model were close to that of experimental results. [ABSTRACT FROM AUTHOR]

A densely-packed IRMOF-3 membrane (S-IRMOF-3(Mem)), ∼55 μm in thickness, on an Al 2 O 3 disc support was prepared via a sonochemical synthesis route, and the optimal fabrication conditions were established. Bare IRMOF-3 particles (S-IRMOF-3(p)) were synthesized independently to analyze the contribution of the Al 2 O 3 support. The overall physicochemical properties of the IRMOF-3 products produced via the sonochemical route were superior to those prepared by microwave heating. The IRMOF-3 materials produced were characterized by XRD, SEM, EDS-mapping, and N 2 adsorption–desorption measurements. S-IRMOF-3(p) exhibited satisfactory CO 2 adsorption capacities (54 mg/g at 298 K/1 bar; 732 mg/g at 298 K/20 bar) and CO 2 /N 2 selectivity (18 at 298 K/1 bar). Both S-IRMOF-3(Mem) and S-IRMOF-3(p) were assessed as a catalyst for a liquid phase Knoevenagel condensation reaction between benzaldehyde and ethyl cyanoacetate. S-IRMOF-3(Mem) and S-IRMOF-3(p) showed comparable conversions (87–89%) with 100% selectivity after a 4 h reaction at 333 K. The heterogeneous nature of the catalyst was confirmed by a hot filtering experiment, and S-IRMOF-3(Mem) could be recovered easily after the reaction and be recycled several times with little change in product yield. [ABSTRACT FROM AUTHOR]

Amine-functionalized bimetallic zeolitic imidazolate framework-8 (Co/Zn-ZIF-A) with 3-amino-1,2,4-triazole (Atz) was synthesized by a post-synthetic modification and utilized as a heterogeneous catalyst for the synthesis of cyclic carbonates from CO 2 and epoxides. Different amine contents in Co/Zn-ZIF-A materials were controlled by adjusting the ligand exchange reaction time of the of 2-mIM with Atz. Co/Zn-ZIF-A-24 h with the highest amine contents (32% of Atz) achieved an excellent result of 99% conversion of epichlorohydrin with high selectivity of > 99% after 24 h without co-catalyst and solvent under mild conditions (80 oC, 1 bar CO 2). The enhanced catalytic activity is attributed to the acid-base synergistic effect by the combination of bimetallic systems consisting of Zn and Co as Lewis acid sites and the abundant Lewis bases sites of -NH 2 , -NH groups from Atz ligand. A kinetic study of the cycloaddition reaction over Co/Zn-ZIF-A-24 h confirmed an approximately first-order dependence on the epichlorohydrin concentration and CO 2 pressure with an activation energy of approximately 39.5 kJ mol-1. Co/Zn-ZIF-A-24 h catalyst showed good reusability with no obvious loss in catalytic activity during five recycling runs and its structural stability was also confirmed. A plausible reaction mechanism of Co/Zn-ZIF-A catalyst for CO 2 -epoxide cycloaddition was proposed. [Display omitted] • Amine-functionalized bimetallic Co/Zn-ZIFs (Co/Zn-ZIF-A) were synthesized by post-synthetic modification. • Co/Zn-ZIF-A was found to be catalytically efficient for CO 2 /epoxide coupling reaction under mild conditions. • Synergistic effect of amine groups and bimetallic systems on accelerating the epoxide ring-opening. • Co/Zn-ZIF-A demonstrates excellent catalytic activity without solvent and any co-catalyst. [ABSTRACT FROM AUTHOR]

Abstract: The washout effect of summertime rain on surface air pollutants (O3, CO, NO2, SO2, and PM10) has been investigated over South Korea during 2002–2012 using routinely available air-monitored and meteorological data. Three new washout indices for PM10, SO2, NO2, and CO are developed to express the effect of precipitation scavenging on these pollutants. All of these pollutants show statistically significant negative correlations between their concentrations and rain intensity due to washout or convection. The washout effect is estimated for precipitation episodes classified by rain intensity (one set included all episodes and another included a subset of moderate intensity episodes that exclude Changma and typhoons), based on the log-transformed hourly data. The most sensitive air pollutant to the rain onset among these five air pollutants is PM10. The relative effect of the rainfall washout on the air pollutant concentrations is estimated to be: PM10 > SO2 > NO2 > CO > O3, indicating that PM10 is most effectively scavenged by rainfall. The analysis suggests that the O3 concentrations may increase due to vertical mixing leading to its downward transport from the lower stratosphere/upper troposphere. The concentrations of CO are reduced, probably due to both the washout and convection. The concentrations of NO2 are affected by the opposing influences of lightning-generation and washout and this are discussed as well. [Copyright &y& Elsevier]

Abstract: The monolayered nanosheets of layered [Mn1/3Co1/3Ni1/3]O2 are prepared by the exfoliation of protonated Li[Mn1/3Co1/3Ni1/3]O2 compound and applied as a precursor for synthesizing the hollow spheres of manganese cobalt nickel oxide. The hollow spheres of layered [Mn1/3Co1/3Ni1/3]O2 are synthesized via the layer-by-layer (LBL) coating of the nanosheets and polycations on the polystyrene (PS) beads and the following heat-treatment. According to powder X-ray diffraction and diffuse reflectance UV–vis spectroscopy, the layered crystal structure and optical property of [Mn1/3Co1/3Ni1/3]O2 nanosheets are well-maintained upon the coating on the PS beads. The high-resolution transmission electron microscopy clearly demonstrates the hollow sphere morphology of the obtained material. The electrode functionality of the [Mn1/3Co1/3Ni1/3]O2 hollow spheres is verified by cyclic voltammetry. [Copyright &y& Elsevier]

An intention of the present work is to synthesize a quaternary metal oxide by a simple and cost-effective method. MoVMnAg-oxide@Ni-foam is synthesised by one-step hydrothermal method. The as-deposited MoVMnAg-oxide sample is systematically examined through XRD, FESEM, EDS-mapping, and TEM analysis. The electrochemical performance of an MoVMnAg@Ni-foam electrode is tested using CV, GCD, and EIS techniques. MoVMnAg-oxide@Ni-foam has a considerable high areal capacitance of 651 mFcm−2 with 0.13 mWhcm−2 energy at 1.8 mWcm−2 power density in 1 M KOH electrolyte calculated from GCD curves. Also, the electrode shows a diffusion coefficient of 1.52 × 10−7 cm2s−1 along with 91 % of diffusive-controlled contribution and a b -value of 0.51, which depicts faradaic charge storage mechanism. An assembled asymmetric supercapacitor device (MoVMnAg@Ni-foam//AC) delivers an areal capacitance of 312 mFcm−2 with 0.37 mWcm−2 power density at 1 mAcm−2 current density within 0 – 1.5 V voltage window. The asymmetric device showed cyclability and coulombic efficiency of 80.3% and 95% respectively measured up to 10,000 GCD cycles. These results demonstrate the deposition of quaternary metal oxide directly on Ni-foam showing highly competitive electrochemical performance so that they can be utilized in energy storage applications. [Display omitted] [ABSTRACT FROM AUTHOR]

The synthesis of metal-organic frameworks (MOFs) with in-built porphyrin units remains challenging. It takes long synthesis time under carefully controlled reaction conditions, and a mixed-phase with different crystal morphologies is still frequently observed. In this work, Zr-based porphyrinic MOF-525 and MOF-545 in high purity and uniform size were produced through a sonochemical route in 2.5 and 0.5 h, respectively, using zirconyl chloride octahydrate and tetrakis (4-carboxyphenyl) porphyrin. Benzoic acid was used as a modulator for MOF-525, and trifluoroacetic acid for MOF-545. The physicochemical properties of the MOF products were examined by X-ray diffraction, scanning electron microscopy, and N 2 adsorption-desorption isotherms. Additionally, the defect sites in the MOF samples were analyzed by UV–vis spectrometry, thermogravimetric analysis, and inductively coupled plasma mass spectrometer. The sonochemically synthesized MOF samples had more defect sites than the conventionally prepared ones and exhibited improved textural properties. In particular, the MOF-545 had a significantly smaller (ca. 1.0 μ m) particle size than the conventionally prepared sample (ca. 4.8 μ m). The MOF-525 and MOF-545 prepared by the sonochemical route exhibited enhanced hydrolysis of the chemical warfare simulant dimethyl-4-nitrophenyl phosphate (DMNP) and a faster and higher bisphenol-A adsorption than the conventionally prepared MOF samples. MOF-525 and MOF-545 were synthesized through a sonochemical route and tested for the hydrolysis of DMNP and adsorption of BPA. Image 1 • Sonochemical syntheses of zirconium-based porphyrinic MOF 525 and 545 were reported. • High-purity crystals of MOF-525 and MOF-545 were obtained within 2.5 h and 0.5 h, respectively. • These MOFs were tested for the hydrolysis of dimethyl-4-nitrophenyl phosphate (DMNP) and adsorption of bisphenol-A (BPA). • Enhanced performances of these MOFs due to increased defect sites, smaller particles size, and larger BET surface area. [ABSTRACT FROM AUTHOR]

Abstract: A dense gadolinia-doped ceria (GDC) interdiffusion barrier layer as thin as 300nm was successfully fabricated on a rigid anode/electrolyte bilayer substrate using the chemical solution deposition (CSD) process for intermediate temperature solid oxide fuel cells (SOFCs). Drying-related macro-defects were removed by employing drying control chemical additives (DCCA), which effectively relieved drying stresses. The major process flaws caused by the constraining effects of the rigid substrate were completely eliminated by the addition of GDC nanoparticles into the chemical solution, which suppressed the generation of microstructural anisotropy by mitigating the predominant bi-axial substrate constraints. As a consequence, a thin film GDC interlayer was successfully deposited with a high volumetric density, effectively preventing the chemical interaction between the electrolyte and cathode during the fabrication process and subsequent operation. The cell test and microstructural analysis confirmed excellent electrochemical performance and structural and chemical stability. The CSD process presented in this paper is considered to be a promising technology for the practical preparation of GDC thin film barrier layers for intermediate temperature SOFCs based on the film quality, processing costs and potential for large-scale production. [Copyright &y& Elsevier]

Abstract: A 500nm thick thin film YSZ (yttria-stabilized zirconia) electrolyte was successfully fabricated on a conventionally processed anode substrate by spin coating of chemical solution containing slow-sintering YSZ nanoparticles with the particle size of 20nm and subsequent sintering at 1100°C. Incorporation of YSZ nanoparticles was effective for suppressing the differential densification of ultrafine precursor powder by mitigating the prevailing bi-axial constraining stress of the rigid substrate with numerous local multi-axial stress fields around them. In particular, adding 5vol% YSZ nanoparticles resulted in a dense and uniform thin film electrolyte with narrow grain size distribution, and fine residual pores in isolated state. The thin film YSZ electrolyte placed on a rigid anode substrate with the GDC (gadolinia-doped ceria) and LSC (La0.6Sr0.4CoO3−δ ) layers deposited by PLD (pulsed laser deposition) processes revealed that it had fairly good gas tightness relevant to a SOFC (solid oxide fuel cell) electrolyte and maintained its structural integrity during fabrication and operation processes. In fact, the open circuit voltage was 1.07V and maximum power density was 425mW/cm2 at 600°C, which demonstrates that the chemical solution route can be a viable means for reducing electrolyte thickness for low- to intermediate-temperature SOFCs. [Copyright &y& Elsevier]

Here we present the enhanced electrochemical properties of ion gel nanofiber-based electrochromic devices (ECDs) prepared by electrospinning. The ECDs were fabricated by sandwiching prepared electrospun nanofiber webs between two transparent electrodes. The electrochromic behaviors of the ECDs were investigated using cyclic voltammetry, spectroelectrochemistry, and kinetic stability measurements. In order to determine the origin of the enhanced EC behaviors, the morphological structures of the nanofiber were examined by a scanning electron microscope, which showed that an ionic liquid (IL) region enclosed the pores between the nanofibers in the solid phase. The increased IL contents in the interstices of the nanofibers were noted, which would induce higher ionic mobility. Consequently, the fabricated nanofiber-based ECDs showed greatly enhanced device performance in terms of switching speed, cyclic stability, and coloration efficiency. Furthermore, flexible ECDs were fabricated by sandwiching the electrospun webs between two plastic electrodes consisting of silver nanowire/PEDOT:PSS hybrid electrodes. The fabricated device revealed a color switching over the large active area, with the transmittance changes maintained over repeated bending cycles. These nanofiber-based ECDs are evidence of a practical approach by which to realize large-area electrochromic devices with excellent chromatic switching and long-term cyclic stability, suitable both for rigid and flexible devices. Image 1 • We obtained free-standing nanofibers by electrospinning an ion gel composition. • Electrochromic device was fabricated by sandwiching the electrospun nanofibers between electrodes. • The prepared device showed excellent electrochromic performances. • Flexible device was fabricated by sandwiching the electrospun webs between two plastic electrodes. • The fabricated device revealed a reversible color switching over repeated bending cycles. [ABSTRACT FROM AUTHOR]

This study aimed to provide a design and operational approach for a loop-seal, which is the heart of a circulating fluidized bed (CFB). Thousands of CFB systems use this non-mechanical valve to optimize performance by controlling the solids circulation rate while preventing gas mixing between reactors. Nevertheless, its design and operating guidance remains unclear because of its intricate flow characteristics, causing confusion in design and operation of the entire CFB. This study experimentally investigated the three most important elements while designing and operating loop-seal: conditions for initiating solids flow, the maximum obtainable solids flow rate, and quantitative control of solids flow rate. Experiments were conducted in a CFB, which simulated 3 MWth chemical looping combustion (CLC) system that is currently being developed. The onset of solids flow occurs when the gas drag force in horizontal passage overcomes the resistance force generated by the bed of particles. The maximum solids circulation rate was determined by solids height in the supply chamber and pressure around CFB loop. A correlation for quantitative control of solids flow in loop-seal was proposed by the relationship between the gas drag force and particle velocity. Finally, operational conditions for the loop-seal in 3 MWth CLC were proposed. Operating conditions of the loop-seal in 3 MWth chemical looping combustion system derived in this study. [Display omitted] • Flow characteristics in loop-seal was analyzed and design factors were confirmed. • Solid flow started after overcoming resistance force by solid in horizontal path. • Particle velocity in horizontal path increased linearly by drag force of gas. • Solid height in standpipe determined the maximum solid circulation rate. • 3 Nm3/hr of Q sup,in was required for solid circulation of 15 kg/s in 3 MWth CLC. [ABSTRACT FROM AUTHOR]

[Display omitted] • The working capacity and stability of absorbent were studied for CO 2 capture. • MPS-supported epoxide-functionalization of PEHA absorbent was synthesized. • PO-PEHA/MPS adsorbent exhibited the working capacity of 1.8 mmol g−1 in 20 cycle. • When the adsorption time was reduced, the regeneration heat was 2.86 GJ tCO 2 -1. • Adsorbent that is regenerated in 100% CO 2 , not inert (N 2 , He) conditions was developed. N -functionalized solid adsorbents have been studied for post-combustion CO 2 capture. Most studies have focused only on the adsorption condition of the adsorbents. Few studies have focused on the regeneration condition of adsorbents. Regeneration is required under the condition of 100 % CO 2 for high-purity CO 2 separation. Regeneration under inert conditions such as N 2 or He, not under the condition of 100 % CO 2 regeneration are required additional cost for high-purity CO 2 separation. In this study, a macroporous silica (MPS) support, which combined a high surface area, large porosity and large pore volume, was selected as the support to achieve high CO 2 capture performance. Pentaethylenehexamine (PEHA) was selected because of its high amine content, high adsorption capacity, high thermal stability, and low cost. The epoxide functionalization of PEHA was used to suppress the urea formation under regeneration conditions. The working capacity and cyclic stability of epoxide functionalization of MPS-based PEHA adsorbents were investigated. A working capacity of 1.8 mmol g−1 was maintained by repeating adsorption and desorption experiments 20 times under an adsorption condition of 15 % CO 2 and a desorption condition of 100 % CO 2. Additionally, the stability of the adsorbent under a 100 % CO 2 regeneration condition was confirmed by maintaining the working capacity constant during 20 repeated adsorption and desorption cycle experiments. When the adsorption time was reduced to minimize H 2 O adsorption, the regeneration heat of the adsorbent was 2.86 GJ tCO 2 -1. These results demonstrated that the regeneration ability was excellent under the condition of 100 % CO 2 , which is the actual process application condition. This approach is promising for industrial applications of CO 2 capture technology. [ABSTRACT FROM AUTHOR]

Environmental issues have become prominent due to an increase in the plastic wastes, which can be recyclable for an alternative liquid fuel. In this work, the upgraded plastic pyrolysis oil was used to investigate the combustion performance of the 5 kW scale heater. The plastic pyrolysis middle oil (diesel-like fraction, C 11 –C 22) was similar to the properties of the diesel (45.0 MJ/kg and 2.70 cSt). The plastic pyrolysis fuel and diesel blends were prepared. The efficiency of combustion using 10% and 30% pyrolysis fuel blends showed about 58% at a fuel-air equivalence ratio (Ф) of 0.91, which was similar to that of diesel combustion. The highest heater internal temperature was observed to be about 1060 °C (Ф = 0.91). In addition, the flue gas composition of all the blends showed similar concentrations of CO (∼13 ppm) and CO 2 (∼13 vol%). However, a higher NO x concentration was observed with pyrolysis fuel blends (80–130 ppm) than that of diesel due to its higher nitrogen content in plastic waste pyrolysis fuel. Exergoeconomic analysis was also conducted to investigate the plastic pyrolysis fuel efficiency for more evaluation. This study suggested that plastic pyrolysis fuel has a good application prospects as an alternative fuel. [Display omitted] • P-fuel/diesel blends showed good miscibility, showing similar properties of diesel. • The combustion efficiency of a 5 kW boiler was about 58% with the p-fuel blends. • Three blends and diesel had similar concentrations of CO (∼13 ppm) and CO 2 (∼13%). • Higher NOx emission (60–130 ppm) was observed with pyrolysis fuel blends. • Exergoeconomic analysis was conducted to evaluate the values of pyrolysis fuel. [ABSTRACT FROM AUTHOR]

• Pyrolysis oil separator was available for upgrading and separating more diesel grade fuels. • Ni-based catalyst showed the highest deoxygenation due to its high strong acid sites. • MDC-7 led to more light oil production whereas Ni-based favored more middle oil. • Catalytic reactions and coke formation occurred on the strong acid sites. The catalytic upgrading of plastic pyrolysis oil was conducted in a 2-kg-scale pyrolysis oil separation system with or without zeolite 4A, Cu-based (MDC-7) and Ni-based catalysts to produce light (F1), middle (F2) and heavy (F3) oil fractions. From the preliminary separation tests without a catalyst, the separation vapor temperature for diesel-like middle fraction (C 11 - C 22) was determined to be in the range of 107–305 °C. After the pyrolysis oil separation with catalysts, the heavy carbon range (>C 23) sharply decreased from 22.1 wt% in the crude plastic pyrolysis oil to 0.1–1.6 wt% and 7.3–8.4 wt% in the F1 and F2, respectively. Among three catalysts, Ni-based catalyst exhibited the highest deoxygenation capacity (1.23% O in F1 and 0.3% O in F2) owing to its strong acid sites concentration (1.115 mmol/g). Accordingly, the order of the deoxygenation capacity was Ni-based > MDC-7 > zeolite 4A > no catalyst. Moreover, the catalytic reactions (deoxygenation) and coke formation mainly occurred on the strong acid sites. MDC-7 catalyst contributed to more production of C 6 –C 10 range (15.8 %) with aromatic and naphthenic compounds. In contrast, the major catalytic mechanisms of Ni-based catalyst were dehydration, decarboxylation and decarbonylation reactions. In addition, the physical properties of catalytically upgraded pyrolysis oil were close to those of the petroleum-based fuels. Finally, the current study suggested that Ni-based catalyst was a suitable catalyst for the production of diesel-like fraction (C 11 -C 12) with the lowest contents of oxygen from the plastic pyrolysis oil. [ABSTRACT FROM AUTHOR]

Abstract: Satellite measurements (Atmospheric InfraRed Sounder/Advanced Microwave Sounding Unit-A, MODerate resolution Imaging Spectroradiometer) and the Modern Era Retrospective-analysis for Research and Applications (MERRA) reanalysis have been utilized to analyze the relative influence of the climate variability (AO: Arctic Oscillation, ENSO: El Niño-Southern Oscillation, QBO: Quasi-Biennial Oscillation) on the zonal-mean temperature and wind variations over the globe from September 2002 to August 2011. We also extended the usage of MERRA data for the period of 1979–2011; furthermore, three climate indices of AO, NINO3.4, and QBO were used as the corresponding climate indicators. The correlations between the temperature anomalies and the climate indices indicate that the tropospheric temperature variability in the mid-latitude (30–60N) linked to both AO and ENSO has been more pronounced over ocean than over land. However, the low stratospheric temperature variability in the mid-latitude is mainly associated with ENSO and QBO. The north–south symmetric patterns over the globe are seen in the wind anomaly distributions for ENSO and QBO, but not for AO. The ENSO events are globally vigorous but also localized during the recent 9 years compared with those based on the period of 1979–2011. The tropospheric warming and stratospheric cooling phenomena during this period are more remarkable in the recent 9 years, although according to IPCC (2012). their linkage to the ENSO variability is still uncertain. The ENSO is found to have more significant impact on the tropospheric and low stratosphere temperature variability over the tropics in the recent period, consistent with more active zonal wind meridional circulations. The discrepancies between satellite observations and MERRA are also discussed. The estimated relative impact of the three major concurrent large-scale climate phenomena on regional temperature variability can be of great use in its long-term predictability. [Copyright &y& Elsevier]