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[Display omitted] • Nb doping enhances the acidity of Ce-Ti catalysts and anti-poisoning performance. • Zn prefers to adsorb around Nb and the Ce sites are further protected by Nb. • Zn species reduce the specific surface area and occupy acidic sites of CNT. • Anions creates new NH 3 adsorption sites but the activation of adsorbed NH 3 is more difficult. The effect of different Zn species (ZnSO 4 , ZnCl 2 , and ZnO) on Nb-doped Ce-Ti catalyst (CNT) was explored with XRD, N 2 physisorption, NH 3 -TPD, H 2 -TPR, XPS, in situ DRIFTS and DFT calculation. The experimental results show that the deactivation rate of CNT by different Zn species was in the order: CNT-ZC > CNT-ZO > CNT-ZS. Nb doping enhanced the acidity of Ce-Ti catalyst and protected Ce active sites from different Zn species. After different Zn species were loaded on CNT, its specific surface area decreased, and the acid sites were occupied. The results from in situ DRIFTS demonstrated that, after anion poisoning, anions (SO 4 2-, O2–, and Cl-) would create new NH 3 adsorption sites while theoretical calculations also indicated that NH 3 adsorption was enhanced by the poisoning of anions, but the activation of adsorbed NH 3 was more difficult. Finally, in situ DRIFTS reveals that the SCR reaction on CNT is still under both E-R and L-H mechanisms. [ABSTRACT FROM AUTHOR]

Abstract Recently, intensively-investigated multi-functional sensors and luminescent lanthanide detectors have become two fields of intense investigation. Functional combination of these two fields is becoming cutting edge research area. Herein, three new dinuclear lanthanide complexes [Ln 2 (IMBA) 6 (dmp) 2 ] (IMBA = 4-iodo-3-methylbenzoic acid; dmp = 4,7-dimethyl-1,10-phenanthroline; Ln = Eu3+, 1a ; Ln = Gd3+, 1b ; Ln = Tb3+, 1c) are obtained. These complexes are fully characterized by multiple techniques such as single-crystal X-ray diffraction (SCXRD), powder X-ray diffraction (PXRD), thermogravimetric analysis (TGA), elemental analysis (EA) and Fourier transform infrared spectroscopy (FT-IR). Luminescence properties of 1a and 1c , including luminescence spectra, decay lifetimes and quantum yields are discussed in detail. It is noteworthy that 1a shows ultrahigh luminescence quantum yield (QY) of 73%. Besides, it is a highly selective bifunctional sensor for diethyl ether (Et 2 O) and Fe2+, and the Fe2+ can be discriminated easily by the naked eye with limit of detection (LOD) of 1.0 × 10−6 M. Further in-depth research evidences that the sensing of Fe2+ would not be disturbed by Fe3+ or other species. Graphical abstract Three new lanthanide complexes have been prepared. Eu3+ complex shows ultrahigh luminescence QY of 73%. It is a highly selective bifunctional sensor, the sensing of Fe2+ can be discriminated by the naked eyes and would not be disturbed by other species. fx1 [ABSTRACT FROM AUTHOR]

Abstract: A series of Ca doped Ce-Ti oxides prepared by a single step sol-gel method were investigated for the selective catalytic reduction of NO with NH3. The results show that Ca doping had both positive and negative effects on the activities of Ce-Ti oxide. Ca0.1CT possessed the best catalytic activity and widest temperature window. Further investigations on BET, XRD, XPS, H2-TPR and NH3-TPD demonstrated that the good SCR performance of Ca0.1CT could be attributed to the increase in the amount of Ce3+ and surface adsorbed oxygen as well as the enhancement of Brønsted acidity and redox ability. In addition, the good dispersion of active Ce species, the alleviation of support sintering, and the interaction among Ce, Ti and Ca species were also responsible for its enhanced activity.Graphical Abstract: [ABSTRACT FROM AUTHOR]

A series of Ce–Mo–Ti mixed oxide catalysts prepared by a homogeneous precipitation method were evaluated for selective catalytic reduction (SCR) of NO with NH 3 . These catalysts were characterized by BET, XRD, XPS, SEM, TEM and H 2 -TPR. The experimental results indicated that the optimal Ce–Mo–Ti mixed oxide catalyst (Ce 40 Mo 10 Ti) exhibited excellent SCR activity in a wide temperature range of 250–450   °C as well as strong resistance to high gas hourly space velocity, 10% H 2 O or/and 1000 ppm SO 2 . The introduction of Mo could enhance redox property and increase the amount of Ce 3+ , accompanied by the increment of oxygen vacancies and adsorbed oxygen species on the catalyst surface, which were advantageous to the SCR reaction over Ce–Mo–Ti oxide catalyst. In addition, good dispersion of Ce and Mo species on TiO 2 and their synergetic interaction also contributed to its remarkable NH 3 –SCR performance. [ABSTRACT FROM AUTHOR]

The compound {[Zn(μ-dicyanamide)(pyrazinamide)](pyrazinamide)} has been synthesized and further characterized by elemental analysis, single-crystal X-ray diffraction, and thermogravimetric analysis. Structural analysis revealed that the dicyanamide anion acted as bridging ligand in a μ-1,5 mode, resulting a polymeric 1-D chain structure. The pairwise N3-H3B···N1 and N9-H9B···N7, N3-H3A···O2 and N9-H9A···O1, N3-H3B···N7 and N9-H9B···N1 multiple hydrogen bonding interactions, impart enhanced stability to supramolecular structures. Hirshfeld surfaces and fingerprint plots were applied to arrive at the same conclusion, which is stabilised mainly by H-H, N-H, O-H interactions. DNA binding studies showed that the compound had interacted with DNA. [ABSTRACT FROM AUTHOR]

The novel cesium chloride–lactose complex (CsCl·C 12 H 22 O 10 (Cs-Lac), cesium chloride- d -arabinose and l -arabinose complexes (CsCl·C 5 H 10 O 5 , Cs-D-Ara and Cs-L-Ara) have been synthesized and characterized using X-ray diffraction, FTIR, FIR, THz and Raman spectroscopies. Cs + is 9-coordinated to two chloride ions and seven hydroxyl groups from five lactose molecules in Cs-Lac. In the structures of CsCl- d -arabinose and CsCl- l -arabinose complexes, two kinds of Cs + ions coexist in the structures. Cs1 is 10-coordinated with two chloride ions and eight hydroxyl groups from five arabinose molecule; Cs2 is 9-coordinated to three chloride ions and six hydroxyl groups from five arabinose molecules. Two coordination modes of arabinose coexist in the structures. α- d -arabinopyranose and α- l -arabinopyranose appear in the structures of Cs-D-Ara and Cs-L-Ara complexes. FTIR and Raman results indicate variations of hydrogen bonds and the conformation of the ligands after complexation. FIR and THz spectra also confirm the formation of Cs-complexes. Crystal structure, FTIR, FIR, THz and Raman spectra provide detailed information on the structure and coordination of hydroxyl groups to metal ions in the cesium chloride–lactose, cesium chloride-D- and l -arabinose complexes. [ABSTRACT FROM AUTHOR]

High-frequency microforging technology is used to produce micrometer-scale plastic deformation on the surface of material out of the vibration impact of a forging punch, and the cumulative effect of its various frequencies on micrometer-scale plastic deformation can cause changes of surface microstructure and mechanical properties. This study used (1) a self-made machine to treat NiCrBSi alloy, (2) a mechanical comparator and optical microscopy (OM) to study the geometric characteristics of plastic deformation, (3) OM and scanning electric microscopy (SEM) to observe influence on surface microstructure and cracking behavior of the laser cladding layer under microforging, (4) x-ray diffractometer (XRD) to measure the surface residual stress of laser cladding layer before and after forging, and (5) microhardness tester and wearing experimental machine to study changes of microhardness, friction coefficient, and wear characteristics of laser cladding layer after microforging. The results have shown that high-frequency microforging could produce plastic deformation about 150 μm deep on the surface of NiCrBSi alloy clad by laser. Regular dendrite and eutectic crystallization microstructure, which is a peculiar characteristic of the laser cladding layer, was broken into pieces and formed residual compression residual stress on the surface. Resistance to cracking of laser cladding layer improved greatly, microhardness and wearability increased, and the friction coefficient did not under go a noticeable change. [ABSTRACT FROM AUTHOR]

Abstract: A series of Ce-Ti mixed-oxide catalysts were prepared by the sol–gel method for selective catalytic reduction (SCR) of NO with ammonia as reductant. These catalysts were characterized by XRD, BET, and XPS techniques. The experimental results show that the best Ce-Ti mixed-oxide catalyst yielded 98.6% NO conversion, and 100% N2 selectivity at typical SCR reaction temperatures (300–400°C) and the high gas hourly space velocity of 50,000h−1. As the Ce loading (the mass ratio of CeO2/TiO2) was increased from 0 to 0.6, NO conversion increased markedly, but decreased at higher Ce loading. The most active catalyst was obtained with a Ce loading of 0.6. The high activity might be attributed to high Ce loading, strong interaction between Ce and Ti, high concentration of amorphous Ce on the catalyst surface, or the increase of chemisorbed oxygen or/and weakly bonded oxygen species, resulting from the presence of Ce3+ after Ce addition. The effect of the calcination temperature was also investigated, and the optimal calcination temperature was 500°C. The presence of oxygen played an essential role in NO reduction, and the activity of the Ce(0.6)Ti catalyst was not depressed when oxygen concentration was higher than 1%. The effect of SO2 and H2O on the activity of the Ce(0.6)Ti catalyst was bound up with the reaction temperature. [Copyright &y& Elsevier]

[Display omitted] • PbO could deactivate CeO 2 -MoO 3 /TiO 2 catalyst greatly. • The amount of Brønsted acid sites decreased greatly ascribed to reduced surface Ce3+and the interaction between PbO and Mo species. • The oxidation of NO to NO 2 was inhibited due to decreased surface chemisorbed oxygen by PbO. • The PbO poisoning mechanism of CeO 2 -MoO 3 /TiO 2 catalyst was proposed. The impact of PbO on CeO 2 -MoO 3 /TiO 2 catalyst for selective catalytic reduction of NO with NH 3 was studied and analyzed with BET, XRD, XPS, NH 3 -TPD, H 2 -TPR and in situ DRIFTS characterizations. The catalytic activity results showed that PbO could greatly deactivate CeO 2 -MoO 3 /TiO 2 catalyst. PbO could interact with Mo species to form PbMoO 4 while inhibit the transformation from surface Ce4+ to Ce3+, which caused a significant decrease in the surface acidity and reducibility of CeO 2 -MoO 3 /TiO 2 catalyst. The oxidation of NO to NO 2 was suppressed owing to a decline in the amount of surface chemisorbed oxygen. Additionally, the adsorption of NH 3 and NO x on Brønsted and Lewis acid sites was restrained. These factors were responsible for the deactivation of CeO 2 -MoO 3 /TiO 2 catalyst by PbO. The in situ DRIFTS results suggested that the NH 3 -SCR reaction on CeO 2 -MoO 3 /TiO 2 catalyst was governed by E-R and L-H mechanisms, which wasn't changed by PbO. [ABSTRACT FROM AUTHOR]

In this paper, flexible, robustly adhesive, surface smooth and oxide-resistive AgNWs/AZO composite transparent conductive films (TCFs) were prepared by spin-coating solvothermal derived AgNWs followed by magnetron sputtering AZO protective layer, after which, annealing treatment at 200 ℃ for 20 min was adopted to further increase the performance of the composite film. The samples were characterized by means of X-ray diffraction, Raman spectroscopy, scan electron microscopy, scanning probe microscope, UV–Vis spectrophotometer and four point probe. The best result of AgNWs/AZO composite films was the one with a transmittance of 85% at 550 nm accompanied with a low sheet resistance of 19 Ω/□ by controlling the spin-coating times fixed at three. The figure of merit for the composite TCFs was 10.4, which was larger than the value of 8.8 for commercial ITO film. These amazing results would render the AgNWs /AZO composite TCFs an ideal candidate to replace conventional ITO for its potential application in flexible devices including OPV and OLED. [ABSTRACT FROM AUTHOR]