Zhun Dong (ZD) coal, which is characterized by high sodium levels, was burned in a pilot-scale furnace to investigate the behavior of fouling deposits on an oil-cooled probe with different surface temperatures. In this study, the fouling deposits were collected at 1298 K furnace temperature. In addition, the inlet temperatures of the conduction oil were set as 543, 493, and 443 K, which were comparable to the feedwater temperature in the coal-fired boiler economizer. The surface temperatures of the deposition probe varied in the ranges of 733–594, 714–571, and 671–507 K. A digital imaging technique was used to monitor variations in deposit thickness and deposit morphology over time for the three cases. The results revealed that the probe surface temperature had a significant effect on the growth, mineralogy, and microstructure of the fouling deposit. The stable thicknesses of the three fouling deposits fluctuated in the ranges of 9.63–9.82, 12.48–12.54, and 15.31–15.53 mm in the 543, 493, and 443 K cases, respectively. In addition, a low probe surface temperature resulted in the absence of significant sintering in the fouling deposit for the 443 K case.

Cobalt-doped manganese octahedral molecular sieves with an ordered cryptomelanes tructure (OMS-2) were synthesized by ao ne-step hydrothermalm ethod. The cobalt precursor was directly added into the solution before crystallization to allow its incorporation into the mixed-valent framework of K-OMS-2. The structure, redox properties, and surface hydrophobicity of Co-doped K-OMS-2 were examined by X-ray diffraction, FTIR spectroscopy,R amans pectroscopy,S EM,T EM, N 2 sorption, temperature-programmed reduction by H 2 ,X -ray photoelectron spectroscopy,a nd water contact-angle system. The incorporation of Co induced am orphological change in K-OMS-2 from nanorods to nanofibers and an increase in the specific surfacea rea from 70.6 to 188.3 m 2 g À1 .C o-doped K-OMS-2 was shown to be able to completely convert CO at 100 8Ci nt he presenceo fa pproximately 3% water vapor.T he promotion effect of Co on the catalytic activity is believed to originate from the enhanced redox capacity and surfacea rea of K-OMS-2, whereas the improved surfaceh ydrophobicity may induce superiorw ater-tolerant performance.CatalyticC Oo xidation hasb een extensively investigated and has already been applied in the field of air purification,a utomotive exhaust cleaning, CO removal of cigarettes moke, and CO 2 lasers. [1] However,f or the above purposes, the presence of water vapor inevitably leads to catalystd eactivation through temporary poisoning of the exposed active sites. [2] Such strict operation conditions have thus stimulated an increase in the demandt od evelop highly efficient and water-tolerantc atalysts for CO oxidation. Noble-metal catalysts such as Pd, Pt, and Au have been widely recognized as preferred choices, but both high costs and finite resources limit their application. [3] Alternatively,aseries of cheap transition-metal oxides (i.e.,C uO,

This paper presents the measurement of effective heat conductivity of ash deposit based on a novel technique for Zhun Dong coal (ZD) with high sodium in a pilot scale furnace. The variation of deposit thickness with time is determined by digital image technique. In addition, simplified two color method is applied to obtain the deposit surface temperature. Subsequently, the change of the average effective heat conductivity of the ash deposit with deposit growth is calculated by combining the deposit surface temperature and thickness. Meanwhile, mineral phases of the ash deposits were identified by X-ray diffraction spectrometry (XRD); scanning electron microscopy (SEM) was applied to analyze the microstructure of ash deposit, and the corresponding chemical compositions were determined by energy dispersive X-ray spectrometry (EDX). The growth process of the ash deposit on probe 2 was composed of four stages based on digital image technique. This was confirmed by the layer structures of the slagging deposits. In addition, the deposit surface temperature increased with time, and it finally fluctuated around 1255 °C. Meanwhile, the results showed that the average effective heat conductivity of the ash deposit on probe 2 increased linearly with deposit growth. The XRD analysis results of three deposits showed that these deposits had similar mineralogy in every layer structure. The content of gehlenite in the deposit increased with the deposit growth. Moreover, the loss of glass is accompanied by a corresponding increase in crystalline phase.

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The first example of the copper-catalyzed cyclization of 4-(phenylamino)-2H-chromen-2-ones employing the N-methyl moiety of DMF as the source of the methine (CH) group has been developed, providing an efficient synthetic pathway to access novel functionalized 6H-chromeno[4,3-b]quinolin-6-ones in moderate to good yields.

The highly efficient selective hydrogenation of 5-hydroxymethylfurfural (HMF) to 2,5-bis(hydroxymethyl)furan (BHMF) was achieved in a fixed-bed reactor by using inexpensive potassium-doped Cu/Al2O3 catalysts.