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Solid base CaO–CeO 2 mixed oxide catalysts have been synthesized via wet impregnation method and characterized by X-ray diffraction (XRD), Brunauer–Emmett–Teller (BET) surface area analysis, temperature-programmed desorption of CO 2 (TPD-CO 2 ) and scanning electron microscopy (SEM). The catalytic activity was determined by transesterification of palm oil. Optimum biodiesel yield, 95%, was achieved by 50Ca–Ce catalyst under the reaction conditions of 5 wt.% of catalyst, methanol to oil molar ratio of 12:1, reaction temperature of 65 °C and reaction time of 4 h. The high catalytic activity (95%) of 50Ca–Ce catalyst may be due to strong basicity and high BET surface area, which indicate more number of active sites on the catalyst surface for transesterification process. Besides, 50Ca–Ce catalyst showed better reusability than the bulk CaO where it can be reused up to 6 times without a significant loss of catalytic activity (>80%). The lixiviation of CaO active phase was greatly reduced with the presence of strong synergic interaction between CaO and CeO 2 . Deactivation of the catalyst was mainly due to the leaching of CaO active phase into the methanolic solution and pore-filling by fatty acid or glycerol. [ABSTRACT FROM AUTHOR]

Highlights: [•] The analysis of the combustion parameters for different fuel-aided combustion syntheses of Ce0.9Ca0.1O1.9 is investigated. [•] The influence of fuel and its direct correlation with calculated thermochemistry is studied. [•] A complex reaction equation based on stoichiometric mole of fuels to propellant chemistry concept is created. [•] The influence of fuel utilised on the combustion process and on physiochemical properties is examined. [•] Ce0.9Ca0.1O1.9 ceramic from citric acid-aided combustion synthesis showed the highest conductivity (σ 800°c =0.017Scm−1). [ABSTRACT FROM AUTHOR]

Abstract: A simple method based on potentiostatic polymerization was developed for the preparation of ternary manganese oxide-based nanocomposite films. The ternary nanocomposites, which were characterized using x-ray diffraction spectroscopy and x-ray photoelectron spectroscopy, showed that the manganese oxide within the film consisted of MnO2 and Mn2O3. Electrochemical measurements showed that the ternary nanocomposite electrode exhibited high specific capacitance (up to 320.6F/g), which was attributed to the morphology of a polypyrrole/graphene/manganese-oxide (PPy/GR/MnOx) ternary nanocomposite. The experimental approach maximized the pseudocapacitive contribution from redox-active manganese oxide (MnOx) and polypyrrole (PPy), as well as the electrochemical double layer capacitive (EDLC) characteristic from graphene (GR) sheets. Long cyclic measurements indicated that the specific capacitance of the ternary nanocomposite film could retain 93% of its initial value over 1000 charge/discharge cycles, in the potential range of −0.2 to 0.7V versus silver/silver chloride electrode (Ag/AgCl). [Copyright &y& Elsevier]

Abstract: We report on infra-red absorption and thermal desorption experiments, together with first-principles density functional theory calculations, for anisole adsorbed on single-crystal Pt surfaces. Substantial structural deformations were observed, consistent with major changes in the occupancy of molecular π orbitals. Our results lend insight into electronic effects in catalysed hydrogenolysis of substituted benzyl groups, enabling us to explain our recent observation that anisole fails to exhibit the enhanced reaction rate predicted by conventional wisdom. [Copyright &y& Elsevier]

Examines the virulence factors of Edwardsiella tarda and its genetic determinants. Systemic infections caused by the pathogen in fish; Screening of E. tarda PPD130/91 mutants for four virulence factors; Characterization of the TnphoA transposon; TnphoA library and virulence factors.

B Background: b Severe acute pancreatitis (SAP) remains one of the more feared and respected acute surgical conditions, given that patients often have signifcant organ failure and require careful management. The series had 7 deaths, all of whom had SAP, making the overall mortality rate 1.7% for pancreatitis and 17% for SAP. B Conclusion: b Mortality rate for SAP in our centre is lower than published data and this likely reflects better clinical management with improved understanding of the pathophysiology of pancreatitis over the years. [Extracted from the article]

B Background: b Severe acute pancreatitis (SAP) remains one of the more feared and respected acute surgical conditions, given that patients often have signifcant organ failure and require careful management. The series had 7 deaths, all of whom had SAP, making the overall mortality rate 1.7% for pancreatitis and 17% for SAP. B Conclusion: b Mortality rate for SAP in our centre is lower than published data and this likely reflects better clinical management with improved understanding of the pathophysiology of pancreatitis over the years. [Extracted from the article]

Abstract Marble waste is generated in a fairly large quantity in the world and has been causing serious environmental problems. Usually, the marble waste is reutilized as cement replacement or aggregate replacement in concrete production. But these two methods of utilization have some drawbacks. In this study, an alternative method, called the paste replacement method, in which marble dust (MD) is added to replace an equal volume of paste without changing the mix proportions of the paste, was proposed, and a number of mortar mixes with different amounts of MD added as either paste replacement or cement replacement were produced for testing of workability, compressive strength and microstructure. It was found that the addition of MD as paste replacement would improve the strength and microstructure of the concrete produced. More importantly, the paste replacement method is better than the cement replacement method in cement content reduction and waste utilization, leading to greater reductions in the carbon footprint (which is mainly from the cement content) and the amount of waste to be disposed. Graphical abstract Image Highlights • Recycling of marble dust as paste replacement in mortar/concrete is proposed. • Such usage of marble dust would decrease waste disposal and carbon footprint. • Moreover, such usage would also improve strength and microstructure of mortar. • Such usage also allows up to 33% reduction in cement content. [ABSTRACT FROM AUTHOR]

Abstract A large quantity of granite dust (GD) is being generated from the stoneware industry as waste to be disposed. GD is as fine as cement but is chemically inert, and thus its addition to concrete as cement replacement would increase the water/cement (W/C) ratio and reduce the strength. However, its addition as a filler to improve the packing density of the aggregate could reduce the cement paste volume needed to fill the voids and thus the cement content and carbon footprint. And, at least theoretically, such reduction of the cement paste volume without changing the W/C ratio would not reduce the strength. In this study, this prospective filler technology of adding GD to concrete for waste utilization and carbon footprint reduction was explored. A number of mortar mixes with different amounts of GD added either as cement replacement or as a filler to fill voids were produced for testing. The results showed that the filler technology is much better than the cement replacement method for waste utilization and cement content reduction, and in fact would also improve the strength and microstructure of the mortar produced. Graphical abstract Unlabelled Image Highlights • Recycling of granite dust as paste replacement in mortar/concrete is proposed. • Such usage of granite dust would decrease waste disposal and carbon footprint. • Moreover, such usage would also improve strength and microstructure of mortar. • This method is better than the cement and aggregate replacement methods. [ABSTRACT FROM AUTHOR]

In a recent study by the authors, it has been found that the addition of granite dust (GD) as paste replacement (addition of GD to replace an equal volume of cementitious paste with the water/cementitious materials ratio kept constant) to decrease the cementitious paste volume in mortar offers substantial benefits in cement content reduction (and thus carbon footprint reduction), waste utilization, strength improvement and microstructure densification. In this study, the authors extended the research program to evaluate the effects of adding GD as paste replacement on the durability and dimensional stability of mortar. A series of mortar mixes with varying GD volume and water/cement ratio but similar workability achieved by adjusting the superplasticizer dosage were made for mini slump cone test, carbonation test, water absorption test and drying shrinkage test. The test results revealed that adding GD as paste replacement could substantially improve the carbonation and water resistances, reduce the ultimate shrinkage strain and shrinkage rate, and at the same time, reduce the cement content by up to 25%. [ABSTRACT FROM AUTHOR]

Lots of marble dust (MD) are generated in stonework factories and just dumped as waste causing environmental problems. Some researchers proposed to use the MD as cement replacement or aggregate replacement in mortar or concrete but the benefits in cement content reduction and performance enhancement are quite limited. Recently, the authors have developed a new method of using inert waste or fillers as paste replacement for greater benefits. By this method, the waste or filler is added to replace an equal volume of cementitious paste without changing its mix proportions. In this study, the authors applied this method to the use of MD in mortar. A series of mortar mixes with varying MD volumes and water/cement ratios were made for mini slump cone test, carbonation test, water absorption test and drying shrinkage test. The test results revealed that adding MD as paste replacement could substantially improve the carbonation and water resistances, reduce the shrinkage strain and rate, and at the same time, reduce the cement content by up to 33%. [ABSTRACT FROM AUTHOR]

Surface modification of Ar plasma-pretreated poly(tetrafluoroethylene) (PTFE) and poly(vinylidene fluoride) (PVDF) films via UV-induced graft copolymerization with 4-vinylpyridine (4VP), 2-vinylpyridine (2VP) or 1-vinylimidazole (VIDz) was carried out. Electroless deposition of nickel could be carried out on these graft-modified fluoropolymer surfaces after PdCl2 activation. The surface compositions of the graft-modified films were studied by X-ray photoelectron spectroscopy. The adhesion strength between the surface graft-copolymerized fluoropolymer film and the electrolessly deposited nickel was affected by the type of monomers used for graft copolymerization and the graft concentration. The optimum T-peel adhesion strengths of the electrolessly deposited Ni on the 4VP graft-copolymerized PTFE and PVDF surfaces were about 7 and 13 N/cm, respectively. The metal/fluoropolymer assemblies delaminated by cohesive failure inside the fluoropolymer substrates. The enhanced adhesion between the electrolessly deposited Ni and the surface-modified fluoropolymers is attributable to the interfacial charge transfer interactions between the grafted polymer chains and the deposited metals (Pd and Ni), the spatial distribution of the graft chains into the metal matrix and the covalent tethering of the graft chains on the fluoropolymer surface. [Copyright &y& Elsevier]

Herein we report the doping mechanism and impedance study of the Nb-substituted Bi 3 Ta 1-x Nb x O 7 (0 ≤ x ≤ 0.5) prepared via conventional solid-state method at 900 °C over 24 h. The substitutional solid solution crystallised in a cubic fluorite structure, space group Fm-3m and with lattice parameter, a = b = c, in the range 5.4477 (±0.0037)–5.4654 (±0.0011) Å. An insignificant unit cell expansion was observed with increasing Nb 2 O 5 content and the linear correlation between lattice parameter and composition variable showed that the Vegard's Law was obeyed. Both TGA and DTA analyses confirmed that the Bi 3 Ta 1-x Nb x O 7 solid solution was thermally stable as neither phase transition nor weight loss was observed within the studied temperature range, ∼28 °C–1000 °C. The electrical conductivities of these samples were found to increase with increasing Nb concentration; the Bi 3 Ta 0.5 Nb 0.5 O 7 exhibited the highest conductivity, ∼1.2 × 10 −2  S cm −1 at 700 °C with a low activation energy of 1.03 eV. [ABSTRACT FROM AUTHOR]

Abstract: A write-once read-many-times (WORM) memory device based on an acrylate polymer containing electron donating carbazole pendant groups, or poly(2-(9H-carbazol-9-yl)ethyl methacrylate) (PCz), was demonstrated. The as-fabricated device was found to be at its OFF state and could be programmed irreversibly to the ON state. The WORM device exhibited a high ON/OFF current ratio of up to 106, a long retention time in both ON and OFF states, a switching time of 1ms, and number of read cycles up to ∼107. Compared to that of poly(N-vinylcarbazole) (PVK), the well-defined memory property of PCz can be attributed to the presence of the spacer between the pendant carbazole group and the polymer backbone. The molecular spacer has allowed the transition of the pendant carbazole groups from the disoriented state to the ordered face-to-face conformation at the threshold voltage. [Copyright &y& Elsevier]

The films of ferroelectrics LiNbO3 have been prepared by pseudospark electron beam deposition at different substrate temperatures. The pseudospark electron beams possess high power density of 109 W/cm2 and nanosecond duration. The phase composition, crystallinity, and surface morphology of the films were investigated. It was found that both the substrate temperature and the crystallization treatment play important roles in the composition control and crystallization of the films. The study indicates that the technique of the film preparation has some unique advantages and will be promising in photoelectric integrated circuit with further improvement. [Copyright &y& Elsevier]

Presents corrections to an article entitled 'Presynaptic calcium stores underlie large-amplitude miniature IPSCs and spontaneous calcium transients,' published in the volume 3, year 2000 issue of 'Nature Neuroscience.'