- Silicon nanowire arrays - A new catalyst for the reduction of nitrobenzene derivatives
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Silicon nanowire arrays (SiNWAs) are under extensive investigation for solar cells and biomedical applications. This study reports for the first time that hydrogen fluoride-treated (H)-SiNWAs are an efficient catalyst for the reduction of nitrobenzene derivatives. We show that SiNWAs, after hydrogen fluoride treatment, have a high catalytic activity in p-nitrophenol (PNP) reduction. The conversion rate of PNP by H-SiNWAs increases with time and is almost complete within 30 min, which thus indicates catalytic activity comparable to that of platinum nanoparticles. The catalytic activity of SiNWAs is closely related to the chemical composition and specific morphology of the surface. Si-H bonds on the surface are essential for activity, and arrays with longer nanowires showed a higher catalytic activity. Moreover, the activity can be easily regenerated by hydrogen fluoride treatment. It was also found that H-SiNWAs exhibit a similar catalytic activity for the reduction of other nitrobenzene derivatives such as p-nitroaniline and sodium m- nitrobenzenesulfonate. It is concluded that H-SiNWAs may be considered as an environmentally friendly alternative to noble-metal-based catalysts for the reduction of nitrobenzene derivatives. No need to be noble: Hydrogen fluoride-treated silicon nanowire arrays (H-SiNWAs) are an efficient, recyclable catalyst for the chemical reduction of nitrobenzene derivatives. The activity of H-SiNWAs is because of the presence of Si-H bonds and the length of the nanowires. Copyright
- Xu, Yajun,Wang, Lei,Jiang, Wenwen,Wang, Hongwei,Yao, Jianlin,Guo, Qinghua,Yuan, Lin,Chen, Hong
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- Thermal oxidation to regenerate sulfone poisoned Pd-based catalyst: Effect of the valence of sulfur
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Sulfur deactivation is a serious problem which largely limits the industrial application of noble metals as catalysts. Here we report a thermal oxidation method to regenerate sulfone poisoned Pd/C catalyst applied in the hydrogenation of sodium-m-nitrobenzene sulfonate (SNS). It was found that the initial activity of Pd/C catalyst could be substantially recovered after treating it in air at temperatures as low as 100 °C. And the catalyst could be reused for at least 20 times without the significant loss of activity. The properties of deactivated and regenerated catalysts were studied in detail by BET measurement, X-ray photoelectron spectroscopy (XPS), temperature programmed desorption (TPD), and Fourier transform infrared spectroscopy (FT-IR). The results indicated that the main surface sulfur species found on deactivated and regenerated Pd surfaces were Sn and sulfate (SO4), respectively. The change of the valence of sulfur species was found to be the key factor influencing the catalytic activity of the Pd-based catalyst. the Partner Organisations 2014.
- Xu, Tieyong,Zhang, Qunfeng,Jiang, Dahao,Liang, Qiuxia,Lu, Chunshan,Cen, Jie,Li, Xiaonian
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- CERAMIDE GALACTOSYLTRANSFERASE INHIBITORS FOR THE TREATMENT OF DISEASE
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Described herein are compounds, methods of making such compounds, pharmaceutical compositions and medicaments containing such compounds, and methods of using such compounds to treat or prevent diseases or disorders associated with the enzyme ceramide galactosyltransferase (CGT), such as, for example, lysosomal storage diseases. Examples of lysosomal storage diseases include, for example, Krabbe disease and Metachromatic Leukodystrophy.
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Paragraph 00382; 00383
(2018/07/29)
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- Production method for preparing sodium m-aminobenzene sulfonate by means of continuous hydrogenation reduction
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The invention belongs to the field of fine chemical engineering, and in particular relates to a production method for preparing sodium m-aminobenzene sulfonate by means of continuous hydrogenation reduction. The method is characterized in that a sodium m-nitrobenzene sulfonate solution is pumped into multiple stages of hydrogenation reaction kettles which are in series connection, and a multi-element catalyst is added into all the reaction kettles; overflow pipes used for conveying a reaction solution are arranged among all the hydrogenation reaction kettles, and a microporus filter used for filtering the catalyst is installed at the front end of each overflow pipe; the reaction solution enters the next kettle by means of liquid level difference after being filtered by the microporus filter; furthermore, balance pipes used for transmitting hydrogen are arranged among all the hydrogenation reaction kettles so as to maintain all the hydrogenation reaction kettles to be communicated with one another in a pressure balance way; therefore, the sodium m-aminobenzene sulfonate can be prepared by means of continuous hydrogenation reduction. After the catalyst provided by the invention is adopted, a condensation side reaction producing azo compounds and oxidized azo compounds is effectively avoided in a high concentration hydrogenation process, dimer and polymer side reactions caused by a deamination reaction can be avoided, and the problem that tarry matters, formed in the side reactions, cover the surface of the catalyst and become catalyst poisons can be solved.
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Paragraph 0027-0028
(2017/07/21)
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- A facile approach of preparing nickel nanoparticles on porous silicon surface and its catalytic activities on reducing of nitroaromatics
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A facile approach of preparing nickel nanoparticles (Ni NPs) on porous silicon (PSi) surface and the catalysis towards reduction of nitroaromatics are depicted in this work in detail. When the PSi chip was immersed in the mixture of 40 % ammonium fluoride and 0.02 M nickel sulfate solutions with volume ratio of 1:1 at 60°C for 15 min, a large number of Ni NPs were generated on PSi surface, which exhibited high catalytic activities on reducing nitro groups of aromatics in the presence of sodium borohydride at ambient temperature. A suggested mechanism of Ni NPs generation on PSi surface was put forward according to theoretical and experimental analyses. The resultant Ni NPs on PSi surface were demonstrated with scanning electron microscopy and the reducing reactions are monitored with ultraviolet-visible spectroscopy.
- Liu, Xiang,Cheng, Heming
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p. 263 - 267
(2014/07/08)
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- Process for monoacylating water-soluble organic amino compounds
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A process for the monoacylation of water-soluble organic amino compounds with 2,4,6-trifluoro-s-triazine, which comprises introducing all reactants simultaneously and continuously in the amounts necessary for the required throughput into the reaction space and removing the resultant reaction products continuously therefrom.
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