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The wetting and corrosion behavior of the corundum substrate anode by CaO–SiO 2 –MgO molten slag was investigated via the joint application of the sessile drop method with applied voltage and SEM-EDS technique. The slag drop exhibited a good wettability on the corundum substrate. The apparent contact angle at zero voltage slightly exceeded that at a 1 V applied voltage but was lower than those at 1.5 V and 2 V ones. Low applied voltage of 1 V had little effect on the corundum substrate's direct dissolution corrosion processes; high ones of not less than 1.5 V caused the electrode reaction to occur. The stirring effect of O 2 bubbles from the anode reaction aggravated the substrate's direct dissolution and physical stripping. It was found that the applied voltage could inhibit the slag penetration, and the apparent contact angle had no obvious relation with the direct dissolution thickness and penetration depth. A thin but almost continuous MgO⋅Al 2 O 3 (MA) layer could form at the slag/substrate interface at the applied voltage of 1.5 V. These results indicate the positive effect of applied voltage on the distribution of interfacial products and the molten slag penetration in reducing the corrosion of corundum anode under certain conditions. However, when the applied voltage was too high, the vigorous electrode reaction could aggravate the direct dissolution and physical stripping of the corundum anode, and damage the continuation of the formed interface product layer with a high melting point. [ABSTRACT FROM AUTHOR]

With the aid of TiO 2 and Ag/TiO 2 composites with ultrahigh specific surface areas (about 400 m 2 g −1 ), we demonstrated a facile controlled strategy to adjust the photooxidation activity of Ag/TiO 2 in the photocatalysis degradation process of Rhodamine B (RhB). A series of photocatalysis experiment results indicated that the selective oxidation of RhB could be performed through changing irradiation light. When the as-prepared unannealed Ag/TiO 2 was used as photocatalyst, Rh-110 was produced only under visible light irradiation. Instead, RhB would be oxidized completely under ultraviolet irradiation or using the annealing Ag/TiO 2 . Although there were many photocatalysis degradation mechanisms of RhB in previous literatures, we have not found an appropriate mechanism to explain this phenomenon. Radical-trapping tests indicated that the effect of superoxide anion radical was more important than hydroxyl radical in the forming process of Rh-110, and hence the selective oxidation mechanism of Ag/TiO 2 was suggested according to the role changing of Ag nanoparticles on the composites under visible and ultraviolet irradiation. [ABSTRACT FROM AUTHOR]

• A copper-based surface model with ZrO 2 clusters supporting is constructed. • The adsorption mechanisms of MSR reactants are studied via DFT calculations. • The ZrO 2 -doped copper surface shows considerable adsorption performance. • Oxygen vacancies in specific surface sites further promote adsorption capacity. The surface adsorption mechanisms of copper-based catalysts for hydrogen production from methanol are investigated by density functional theory (DFT) calculations. In this study, pure and ZrO 2 - modified copper surfaces are concerned. All the surfaces and adsorbed configurations are optimized via Dmol3 module and analyzed by density of states (DOS), charge transfer and electron density difference. The results show that the O–Cu bond of pure copper surface and the O-Zr bond of ZrO 2 -modified surface is formed respectively after adsorption of various adsorbates, where strong interactions and electron migration are detected. Compared to pure copper surface, the ZrO 2 -modified one shows better adsorption capacity and catalytic activity for hydrogen production. The inhibition of carbon monoxide discharge for stable ZrO 2 -presorbed configurations are confirmed. In addition, the oxygen vacancy is also considered, and the O-defective surface of O v 1 is the most stable configuration, which can be easily formed. This is beneficial to further hydrogen production reactions like MSR. The heterogeneity of catalyst surface that ZrO 2 brings great promotes the adsorption capacity, and this provide theoretic basis for future catalyst design. [Display omitted] [ABSTRACT FROM AUTHOR]

• Pd-CoO∙TiO 2 /TiO 2 and Pd-CoO x /TiO 2 represent high catalytic activity and selectivity in CO 2 transformations. • CO is a good prober toward Lewis acidic centers for the reaction intermediates of methoxy species. • Lewis acidity and alkalinity are readily controllable on the catalysts surfaces. • High catalytic performances are derived from the cooperation of Lewis acid/base on the interfaces. • The studies provide an alternative solution to relate the catalytic activity with the strengths of Lewis acids and bases. A highly attractive aim is to turn CO 2 into useful chemicals selectively and efficiently, but it still retains great challenging to understand the relations between catalytic performances and interface properties. Here, we report an alternative solution to relate the catalytic activity with the strengths of Lewis acids and bases on the Pd-CoO x interfaces. CoO∙TiO 2 /TiO 2 and CoO x /TiO 2 possess the wide spectrum of Lewis acid/base centres, and give the low selectivity and conversion. The introduction of Pd can focus them on the intrinsic centres, and makes Pd-CoO∙TiO 2 /TiO 2 and Pd-CoO x /TiO 2 represent the ideal catalysis. With temperature-programmed desorptions of CO 2 , CO and NH 3 , it is evidenced that the catalytic hydrogenations of CO 2 to CO, CH 4 and CH 3 OH depend on the cooperation of the Lewis acidic/alkaline centres on the interfaces. The studies provide guidelines for rational design and synthesis of heterogeneous catalysts including but not limited to CO 2 hydrogenation. [Display omitted] [ABSTRACT FROM AUTHOR]

Abstract: The antioxidant capacities of 15 commercial raspberry varieties grown in North China were evaluated and their anthocyanin profiles determined by LC–ESI-MS. Total polyphenol content (TPC), total flavonoid content (TFC), total anthocyanin content (TAC) and antioxidant capacities (AOC) of the 15 raspberries were measured, respectively and the results showed that the TPC, TFC and TAC contents of raspberries correlated well with their antioxidant capacities. Raspberries with higher contents of phytochemicals showed higher antioxidant capacity. The results indicated that the 15 raspberry varieties may be divided into three groups according to their anthocyanin component analysis. The first group was made up of Triple Crown, Shawnee, and Navaho varieties with identical anthocyanin profiles and dark red color. The second group included Canby, Bristol and Mac black varieties, which possessed higher TAC/TPC ratio and contribute more to antioxidant capacity and the rest of the varieties were in the third group with lower antioxidant capacities. The higher phytochemical contents and antioxidant activities of raspberry varieties in the second group indicated that their consumption would be more beneficial to health. [Copyright &y& Elsevier]

Abstract: The dependences of the absorption spectra of chrome azurol S (CAS) and Al3+–CAS complexes on the concentration of ionic liquids (ILs), 1-alkyl-3-methylimidazolium bromide ([C n Mim]Br, with n =8, 10, 12), were measured at 298.15K in aqueous solutions with pH=5.6. It is found that ILs can induce the significant red-shifts of the wavelength at the absorption maximum (λ max) of Al3+–CAS complex from 545 to 646nm for [C8Mim]Br, and to 642nm for [C12Mim]Br and [C16Mim]Br, respectively. Accompanying the red-shifts, the absorbance at λ max, and thereby molar absorptivity (ɛ), changes markedly with the IL concentration, and consequently the effect of ILs on the absorbance at λ max is systematically investigated in this work. Along with the experimental results of resonance light scattering, the sensitization mechanism is analyzed from the aggregation of the ILs and the interactions of ILs with CAS and Al3+–CAS complexes. It is shown that the hydrophobic interactions of IL subaggregates with CAS in Al3+–CAS complex are the crucial factor for the sensitization. [Copyright &y& Elsevier]

Abstract: The polymer–ammonium complexes are an important class of proton conducting polymer electrolytes. In this work, poly(ethylene oxide) (PEO)–NH4SCN electrolytes were prepared over a large range of the salt content, and their FT-IR spectra were measured at room temperature. Based on the assignments of each band in the spectral envelope of SCN−1, their relative intensities are determined by the use of FT-IR technique. Following the experimental results and spectral analyses, this paper reports the interactions, the various ionic associations, the changes of the ionic association with NH4SCN content, and the characteristics of structure in PEO–NH4SCN electrolytes. It is shown that the hydrogen bonds of PEO and NH4SCN exert the great effect to the ionic association, the interactions of PEO with NH4SCN, and PEO crystallinity, in particular, under the condition of high NH4SCN content. In addition, the differences of ionic association among PEO–NaSCN, PEO–KSCN and NH4SCN electrolytes are also compared in this paper. [Copyright &y& Elsevier]

Abstract: Solid polymer electrolytes are potentially useful electrolytes to be applied in high-energy batteries. In the present work, a novel polymer electrolyte, polyethylene oxide (PEO)–NaSCN–AlCl3, was prepared and investigated by FT-IR spectroscopic techniques. Based on the FT-IR data, the bands in the CN stretching envelope have been assigned and the effect of AlCl3 on ion–ion and ion–polymer interactions in the polymer electrolyte has been examined. It is shown that the Lewis acid–base interaction of AlCl3 with SCN1− leads to the formation of the complex anions AlCl3SCN− and Al2Cl6SCN−, depending on the content of AlCl3 and/or NaSCN in PEO; the preferential interactions of AlCl3 with crystal complex P(EO)3NaSCN occur in PEO–NaSCN–AlCl3 electrolytes; the AlCl3–NaSCN complex anions can play a plasticization role in PEO–NaSCN–AlCl3 electrolyte, and are expected to be a important factor to improve the conductivity and to enhance the cation transference number. In addition, the interactions between AlCl3 and ether oxygen of PEO were analyzed, and their effect on ionic association was also discussed. [Copyright &y& Elsevier]

• Combustion mechanism and dynamics of jatropha oil droplets are studied. • Flame spread velocity and flame spread limit of jatropha oil droplets are determined. • The flame spread behavior of jatropha oil droplets is classified into three modes. The present study investigated the flame spread and combustion characteristics of two jatropha oil droplets, droplet A and B. Specifically, the pyrolysis characteristics of jatropha oil were studied using thermogravimetric and differential scanning calorimetry (DSC) analysis. Liquid chromatography-mass spectrometry (LC-MS) was used to analyze the components in jatropha oil. Then, the flame spread from droplet A to droplet B and combustion dynamics of two droplets were studied in a constant volume chamber under atmospheric pressure and room temperature (300 K). The effects of normalized droplets spacing S/d 0 (2.7–4.9) on flame spread were also studied. The results showed that the combustion of jatropha oil droplet containing three stages: initial expansion stage, quasi-steady combustion stage and micro-explosive combustion stage. Periodic puffing and micro-explosion occurred during micro-explosive combustion stage. This is due to the superheating of low boiling-point components produced by pyrolysis of long-chain fatty acids in jatropha oil. The duration of initial expansion stage increases significantly with the increase of droplet spacing. When the normalized droplet spacing reaches 4.9, the second droplet cannot ignite and reached flame spread limit. Interestingly, the flame spread velocity increase at first and then decrease with increase droplet spacing. This is because the diffusion flame is cooled by unburned droplet when the spacing is relatively small. However, when the spacing is relatively large, the flame spread velocity mainly depends on the duration of second droplet in first stage. [ABSTRACT FROM AUTHOR]

Abstract High performances, cost-effectiveness, and facile preparation of electrode materials are of utmost importance for supercapacitors in practical applications. Herein, Ni(HCO 3) 2 nanoparticles (NPs) of low cost and environmental friendliness were embedded into polydopamine-reduced graphene oxide (PDA-RGO) networks via cost-effective hydrothermal route. It is shown the conducting PDA can uniformly distributes and robustly immobilizes Ni(HCO 3) 2 NPs in the nanocomposite while the ionic channels are improved for electrolyte access. Consequently, the as-prepared Ni(HCO 3) 2 -PDA-RGO composite offers the high Faradaic capacity of 870 C g−1 at 0.5 A g−1 and moderate rate capability. Furthermore, the assembled Ni(HCO 3) 2 -PDA-RGO//activated carbon hybrid supercapacitor (HSC) delivers a specific capacity of 192 C g−1 at 0.5 A g−1 within operation voltage window of 1.7 V. The maximum energy density of the HSC reaches to 45.3 Wh kg−1 at a power density of 425 W kg−1, and the initial specific capacity maintains 90.5% after 3000 successive charge-discharge cycles. The high energy density and good cycleability certify the potential of the ternary Ni(HCO 3) 2 -PDA-RGO composite in efficient and long lifetime energy storage systems. [ABSTRACT FROM AUTHOR]