Publications by authors named "Keqiang Sun"

Capitalizing on the recent advances in image generation models, existing controllable face image synthesis methods are able to generate high-fidelity images with some levels of controllability, e.g., controlling the shapes, expressions, textures, and poses of the generated face images.

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The direct redox reaction (galvanic displacement) between Pd(2+) and substrate Si was used to deposit Pd on Si, and the Pd-Si catalysts enabled a chemoselective hydrogenation of para-chloronitrobenzene with the selectivity for para-chloroaniline higher than 99.9% at complete conversion of para-chloronitrobenzene.

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Adding a small amount of fully dispersed Pt entities onto the Au surface in Au/SiO(2) catalyst is found to be an efficient approach to improve the catalytic activity of Au (up to 70-fold) for the hydrogenation of α,β-unsaturated carbonyl compounds, without alternating its selectivity towards C=O or C=C bond hydrogenation.

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The effect of Au(3+) percentage in Au/TiO(2) on its storage stability at room temperature was studied by varying the drying temperature and storage duration of a deposition-precipitation prepared Au/TiO(2) sample. Carefully-designed room temperature storage in a desiccator, in the dark to exclude any interference of light irradiation, was referenced to the freezing storage (255 K) in a refrigerator. The samples were characterized by well-calibrated H(2)-TPR, TEM and TG measurements.

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The evolution of nickel speciation during the successive preparation steps of Ni-SiO(2) catalysts is studied by UV-Vis-NIR, FT-IR, DTG, TPR and TEM. The study focuses on the effect of the number of chelating ligands in the precursor complexes [Ni(en)(x)(H(2)O)((6-2x))](2+) (en = ethylenediamine, x = 1, 2, 3) on the adsorption on silica, and on nickel speciation after thermal treatment. When the en:Ni ratio in solution increases from 1 to 3, the most abundant complex is [Ni(en)(H(2)O)(4)](2+) (64% of all Ni complexes), [Ni(en)(2)(H(2)O)(2)](2+) (81%) and [Ni(en)(3)](2+) (61%), respectively.

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Dibenzodioxin adsorption/desorption on solid surfaces is an important issue associated with the formation, adsorption, and emission of dioxins. Dibenzodioxin adsorption/desorption behaviors on inorganic materials (amorphous/mesoporous silica, metal oxides, and zeolites) were investigated using in situ FT-IR spectroscopy and thermogravimetric (TG) analysis. Desorption temperatures of adsorbed dibenzodioxin are very different for different kinds of inorganic materials: approximately 200 degrees C for amorphous/mesoporous silica, approximately 230 degrees C for metal oxides, and approximately 450 degrees C for NaY and mordenite zeolites.

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The concentration of alpha-oxygen which can oxidize methane to methanol and benzene to phenol at RT, increases linearly with the amount of introduced extraframework Al on Fe/ZSM-5 catalysts prepared by solid-state exchange of FeCl3 and AlCl3 with H-ZSM-5.

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