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CeO2-WO3 (CW) catalysts were prepared by situ self-assembly method for the selective catalytic reduction (SCR) of NOx with NH3. With the increasing content of WO3, the interaction between WO3 and CeO2 improved, resulting in the formation of more acid sites, CeO2-WO3 solid solution and excellent redox ability, which could enhance the catalytic activity. Furthermore, an excess of WO3 over CW catalysts could decrease the SCR activity due to the attenuation of interaction. Hence, CW-20 (WO3 was 20 wt% over CeO2-WO3) possessed the widest active temperature window and nearly 100% NOx conversion was obtained at 225–400 °C, which relied on the contents of WO3.

The effect of different pH values (8, 9, 10 and 11) on the catalytic activity over CeSiW catalysts was investigated for the selective catalytic reduction of NO by NH3. CeSiW-9 showed a remarkable higher NOx conversion. The strongest interaction was observed between silicotungstic acid and CeO2 over CeSiW-9, resulting in the improvement of redox ability and surface acidity, which could increase the catalytic activity. The superior catalytic performance of the CeSiW-9 catalyst was attributed to the favored pore structures, excellent redox ability and the abundance of surface acid sites, which depended on pH values in the preparation process of CeSiW catalysts.

A series of CeO2 prepared with H2SO4 (C–S), H3PO4 (C–P) and H2SO4 + H3PO4 (C–P–S) were investigated in selective catalytic reduction of NOx with NH3. The sulfates contributed to the improvement of Bronsted (B) acid sites, while phosphates were prone to the enhancement of Lewis (L) acid sites, which could improve the catalytic activity. Furthermore, sulfates existed in the surface of C–P–S and C–S; phosphates occurred on the subsurface region or were highly dispersed on the surface of C–P–S and C–P. Besides, the nitrates adsorbed on the CeO2 and NH3 contacted with the sulfates, which followed the L–H mechanism at 200 °C on C–P–S and C–S. The adsorption and activation of NO and NH3 over C–P occurred at the same active sites, which obeyed the E–R mechanism at 200 °C. C–P–S possessed the best catalytic activity because of the appropriate surface acidity and redox property, and more than 80% conversion of NOx was obtained at 220–450 °C. CeO2 modified by H2SO4 (C–S), H3PO4 (C–P) and H2SO4 + H3PO4 (C–P–S) was prepared and used for selective catalytic reduction of NOx by NH3. The presence of sulfate species over C–S and C–P–S contributed to the formation of surface acidity. CeO2 modified by phosphoric acid favored excellent oxidation ability.

A two dimensional(2D) collision frequency model is developed based on the 2D solid state plasma concentration distribution model and mobility model for a heterogeneous Si/Si 1−x Ge x /Si structure SPiN(Surface PiN) devices, which are the basic radiating elements in the reconfigurable solid state plasma antenna. The lower collision frequency can be achieved when the Ge mole fraction x and applied voltage increase at the temperature T=300 K, and that the basically uniform distribution of collision frequency can be obtained for Ge mole fraction x=0.3. Moreover, radiation efficiency and the maximum gain of the antenna for the different collision frequency have also been studied. The proposed model can be a handful for the designing of the solid state plasma antenna.

A series of Mn2O3 catalysts were prepared by different hydrothermal temperatures and employed to the catalytic oxidation of benzene due to their high activity. The Mn-120 sample with three-dimensional (3D) hierarchical cube-like morphology mainly exposed (2 1 1) crystal plane exhibited the best catalytic activity for the oxidation of benzene and achieved the benzene conversion of 90% at 248 °C. Meanwhile, the best catalytic performance of the Mn-120 sample was attributed to the most amounts of the Mn3+ species and surface-adsorbed oxygen. With the increase of Mn3+ species, the oxygen binding capacity of Mn-120 was reduced, which could increase its oxygen mobility. The abundant adsorbed oxygen species of Mn-120 could improve the replenishment capacity of lattice oxygen species, and the reaction pathway of catalytic oxidation of benzene over MnO2 obeyed the Mars-Van-Krevelen (MVK) mechanism.

A series of Fe–Ti-Ox catalysts calcined at different temperatures (signed as Fe–Ti-x, and x symbolized the calcination temperature of 300, 400, 500, 600 and 700 °C, respectively) were prepared and studied for the catalytic hydrolysis of HCN in the presence of H2O. The results implied that Fe–Ti-4 (the calcination temperature was 400 °C) showed the best catalytic hydrolysis efficiency of HCN and the abundant productions (CO and NH3). With the calcination temperature increasing, the catalytic hydrolysis of HCN activity decreased dramatically, which was related to the reduction of specific surface areas and redox property, the formation of rutile TiO2 and decline in quantity of Fe2+ species. Besides, Fe–Ti-Ox catalysts with amorphous states of TiO2 could enhance catalytic hydrolysis of HCN, which depended on the effect of calcination temperature during the preparation process of Fe–Ti-Ox catalysts.

Using bisphenol A (BPA) as the template and the modified kaolinite as solid-support substrates, a novel surface molecularly imprinted polymer (S-MIPs) was prepared by combining self-assembly molecular imprinting technology and sacrificial support process. The resulting composites were characterized by transmission electron microscopy, thermogravimetric analysis, and nitrogen adsorption–desorption. The results of batch adsorption experiments suggested that pH 6.0 in testing solution was the optimal adsorption condition. The kinetic properties of S-MIPs were well described by the pseudo-second-order equation, which indicated that chemical process could be the rate-limiting step in the adsorption process for BPA. Equilibrium data were described by the Langmuir and Freundlich isotherm models. Results suggested that Langmuir isotherm model was fitted to the experimental data significantly better than the other models. Selectivity experiments showed the high affinity of target BPA over competitive compo...

Zinc silicate (Zn2SiO4) nanorods with diameters of 90–100 nm and lengths of up to 600–700 nm have been successfully prepared by a simple hydrothermal route without the assistance of any templates or surfactants. The characterisations of the products were carried out by X-ray diffraction (XRD), field-emission scanning electron microscopy and transmission electron microscopy technology. On the basis of XRD and scanning electron microscopy analyses of the products at different reaction time periods, an Ostwald ripening mechanism is proposed to elucidate the formation mechanism of the nanorod structure. The electrochemical performance of the as-prepared Zn2SiO4 nanorods was investigated by a galvanostatic charge–discharge method. The results have shown that the Zn2SiO4 nanorods exhibited a higher discharge capacity and better cyclability than the Zn2SiO4 bulk materials.

Systemic study on thermal dilute-acid hydrolysis of cotton straw has been conducted. The process of sequential two-step reaction has been established, which can greatly improve the utilization efficiency of lignocellulosic biomass. The hydrolyses were carried out in an 1 L erlenmeyer flask placed in the pressure steam sterilizer, where the hydrolysis retention time (0–60 min), liquid to solid ratio (8–14:1) and acid concentration (0–1 mol/L) were examined for the first stage. Optimization of first stage hydrolysis is desirable to achieve the highest yield of the sugars from hemicellulose and also as a pretreatment for the second acid hydrolysis. The solid residuals were further dilute-acid (0.2 mol/L) hydrolyzed in this study. This second-stage hydrolysis mainly completed the conversion of cellulose to levulinic acid and formic acid. At last, dilute-acid conversion of cotton straw to sugars (in the first stage), levulinic acid and formic acid (in the second stage) was completed.

Bimetallic Fe/Ni nanoparticles were synthesized and their nitrate reduction capacity was studied. Nitrate (354 mg L(-1), equal to 5.71 mmol L(-1)) reduction was performed using Fe/Ni nanoparticles with various Ni contents (1.0, 5.0, 10 and 20%) in an unbuffered condition. Optimum nitrate reduction rate (1.03 +/- 0.087 x 10(-4) mol x min(-1) x greduc(-1)) was obtained with 5.0% nano-scale Fe/Ni, while only 25% nitrate (1.05 +/- 0.091 x 10(-5) mol x min(-1) x greduc(-1)) was transformed by nano-scale Fe(0) within the same reaction time, which means that these bimetallic nanoparticles are obviously more reactive than monometallic nano-scale Fe(0). For this bimetallic system a near-neutral initial pH (6.5) is more favourable than an acidic condition (2.0 and 4.0). Relatively air-stable nano-scale Fe/Ni particles were developed by slowly aging them for 22 h and exhibited similar reactivity to freshly synthesized nano-scale Fe(0). Although undesirable transformation of nitrate (91.0 +/- 0.37%) to ammonium was observed in this study, Fe/Ni particles showed a much higher nitrate reduction rate and an optimum reduction rate at near-neutral pH, which may have important implications for nitrate-contaminated site remediation.

Catalytic reduction of nitrate in groundwater by sodium formate over the catalyst was investigated. Pd-Cu/γ-Al2O3 catalyst was prepared by impregnation and characterized by brunauer-emmett-teller (BET), inductive coupled plasma (ICP), X-ray diffraction (XRD), transmission electron microscopy (TEM) and energy dispersive X-ray (EDX). It was found that total nitrogen was effectively removed from the nitrate solution (100 mg/L) and the removal efficiency was 87%. The catalytic activity was affected by pH, catalyst amount used, concentration of sodium formate, and initial concentration of nitrate. As sodium formate was used as reductant, precise control in the initial pH was needed. Excessively high or low initial pH (7.0 or 3.0) reduced catalytic activity. At initial pH of 4.5, catalytic activity was enhanced by reducing the amount of catalyst, while concentrations of sodium formate increased with a considerable decrease in N2 selectivity. In which case, catalytic reduction followed the first order kinetics.

The pyrolysis oil from lignocellulosic biomass as a renewable resource has been exploited and utilized. Microbial degradation of the pyrolysis oil by several fungi strains was investigated. The results showed that Trichoderma viride, Aspergillus niger, Trichoderma harzianum, Penicillium oxalium and Phanerochaete chrysosporium could grow well using the pyrolysis oil as carbon source, while the growth of plant pathogen Cladosporium cucumerinum and Botrytis cinerea was inhibit by the pyrolysis oil. HPLC analysis showed that some water-soluble compounds in pyrolysis oil are biodegradable.

4008 Background: Sorafenib (SOR) has become the standard treatment for advanced hepatocellular carcinoma (HCC). Hand-foot skin reaction (HFSR) is one of the most common adverse events associated with SOR and its occurrence can impact patient quality of life and lead to dose modification or interruption, both of which may negatively impact clinical outcomes. This randomized controlled trial is the first large prospective study to investigate the prophylactic effect of urea-based creams on HFSR associated with SOR. Methods: Patients with advanced HCC treated with SOR were randomly assigned 1:1 to receive prophylactic urea-based cream (Arm A) or best supportive care (BSC) following development of HFSR (Arm B). SOR was administered 800 mg daily. Urea-based cream was given twice daily for up to 12 weeks starting on Day 1. BSC was at the physician’s discretion and excluded urea-based creams. The primary endpoint was the incidence of all-grade HFSR in the first12 weeks. Results: Eight hundred sixty eight patients were enrolled; 439 patients in Arm A and 432 patients in Arm B. There was no difference of baseline characteristics between two arms. Over the 12 week period of study, the incidence of all-grade HFSR was significantly lower in Arm A compared to Arm B; n=246 (56.0%) patients in Arm A versus n=318 (73.6%) patients in Arm B, p