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Practical Synthesis of NFSI Derivatives through ArSO_(2) NHF without F_(2)

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Chinese Journal of Chemistry 2022年第24期40卷 2956-2962页

作者： Yu-Yang Zhang xiu-Hua Xu Feng-Ling qing Key Laboratory of Organofluorine Chemistry Shanghai Institute of Organic ChemistryUniversity of Chinese Academy of ScienceChinese Academy of Sciences345 Lingling LuShanghai200032 China

N-Fluorobenzenesulfonimide (NFSI) is one of the most popular fluorine-containing reagents for fluorination, imidation, sulfonylation, and oxidation reactions. Consequently, a variety of NFSI derivatives were designed and synthesized to modify the reactivity and/or selectivity of the parent reagent. However, the hazardous F_(2) was inevitably required for the synthesis of NFSI derivatives. Herein, we disclosed a practical synthesis of various NFSI derivatives without F_(2) in common organic chemistry laboratories. This synthetic protocol started from NFSI through pyridine-promoted desulfonylation for formation of N-fluoroarenesulfonamide (ArSO_(2)NHF) and followed by condensation with arenesulfonyl chlorides. The reduction potentials and fluorinating reactivities of these NFSI derivatives demonstrated that NFSI derivatives bearing the electron-withdrawing groups on benzene ring had the higher oxidizing and fluorinating abilities than NFSI.

关键词： Fluorine Fluorinating reagent Sulfonamides Synthetic methods Desulfonylation NFSI Condensation

Synthesis and Properties of CF3(OCF3)CH-Substituted Arenes and Alkenes

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Chinese Journal of Chemistry 2020年第8期38卷 847-854页

作者： Wen-Qi Xu xiu-Hua Xu Feng-Ling qing Key Laboratory of Organofluorine Chemistry Center for Excellence in Molecular SynthesisShanghai Institute of Organic ChemistryUniversity of Chinese Academy of ScienceChinese Academy of Science345 Lingling LuShanghai 200032China Key Laboratory of Science and Technology of Eco-Textiles Ministry of EducationCollege of ChemistryChemical Engineering and BiotechnologyDonghua University2999 North Renmin LuShanghai 201620China

A silver-mediated oxidative trifluoromethylation of easily accessibleαα-trifluoromethyl alcohols with TMSCF3 was developed to access novel CF3(OCF3)CH-containing *** of CF3(OCF3)CH-substituted arenes afforded synthetically useful CF3O-substituted ***,evaluation of the lipophilicities(log P)indicated that CH(OCF3)CF3 is more lipophilic than the common fluorinated motifs such as CF3,OCF3,and SCF3,thus rendering the CH(OCF3)CF3 motif appealing in drug discovery.

关键词： compounds substituted rendering

Morphology Study for GeV Emission of Nearby Supernova Remnant G332.5-5.6

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Research in Astronomy and Astrophysics 2024年第4期24卷 134-140页

作者： Ming-Hong Luo qing-Wen Tang xiu-Rong Mo Department of Physics School of Physics and Materials ScienceNanchang UniversityNanchang 330031China

A spatial template is important to study nearby supernova remnants(SNRs).For SNR G332.5-5.6,we report a Gaussian disk with a radius of about 1°.06 to be a potential good spatial model in the γ-ray *** this new Gaussian disk,its GeV lightcurve shows a significant variability of about seven *** γ-ray observations of this SNR could be explained well either by a leptonic model or a hadronic model,in which a flat spectrum for the ejected electrons/protons is required.

关键词： ISM:supernova remnants gamma rays:ISM

Production of low-silicon molten iron from high-silica hematite using biochar

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Journal of Iron and Steel Research International 2017年第1期24卷 27-33页

作者： Hui-qing Tang xiu-feng Fu Yan-qi Qin Shi-yu Zhao qing-guo Xue State Key Laboratory of Advanced Metallurgy University of Science and Technology BeijingBeijing 100083China

A new method of utilizing high-silica hematite to produce low-silicon molten iron was *** this method,FASTMELT,which comprised direct reduction and melt separation processes,was applied,with highly reactive biochar as the reductant in the direct reduction *** proposed method was experimentally investigated and the results show that the method is *** the direct reduction stage,ore-char briquette could achieve a metallization rate of 84%-88% and residual carbon of 0.27-0.89mass% at temperature of 1373 K,biochar mixing ratio of 0.8-0.9,and reduction time of 15 *** silica particles remained embedded in the iron phase after the *** the melting separation stage,molten iron with a carbon content of 0.02-0.03mass% and silicon content of 0.02-0.18mass%could be obtained from the metallic briquettes under the above-mentioned conditions;the iron recovery rate was83%-91% and impurities in the obtained metal were negligible.

关键词： High-silica hematite Low-silicon molten iron Biochar Direct reduction Melt separation

Monocyte to High-density Lipoprotein Cholesterol Ratio as a Predictor of Nonalcoholic Fatty Liver Disease in Childhood Obesity

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Current Medical Science 2024年第4期44卷 692-697页

作者： Jun-feng ZHANG Feng-qing CAI xiu-cai ZHANG qing YE Department of Laboratory Medicine Children’s HospitalZhejiang University School of MedicineNational Clinical Research Center for Child HealthHangzhou310052China

Objective Inflammation is involved in the development and progression of nonalcoholic fatty liver disease(NAFLD).The monocyte to high-density lipoprotein cholesterol ratio(MHR)has emerged as a marker for various inflammation-related *** aim of the present study was to investigate the association between the MHR and NAFLD in a population with childhood *** Based on hepatic ultrasound,a total of 504 children with obesity(357 with NAFLD and 147 without NAFLD)were included in the *** correlation between the MHR and NAFLD risk factors was assessed by Pearson’s and Spearman’s *** stepwise logistic regression analyses were conducted to explore the association between the MHR and the risk of *** The MHR in patients with NAFLD was significantly greater than that in patients without NAFLD[0.52(0.44-0.67)versus 0.44(0.34-0.57),Pduals with childhood obesity.

关键词： nonalcoholic fatty liver disease obesity monocyte-to-high-density lipoprotein ratio marker

Iron-Mediated Chlorotrifluoromethylation of Alkenes with Sodium Trifluoromethanesulfinate

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Chinese Journal of Chemistry 2016年第5期34卷 465-468页

作者： Bin Yang xiu-Hua Xu Feng-Ling qing Key Laboratory of Organofluorine Chemistry Shanghai Institute of Organic Chemistry Shanghai 200032 China College of Chemistry Chemical Engineering and Biotechnology Donghua University Shanghai 201620 China

An iron-mediated three-component chlorotrifluoromethylation of both styrenes and aliphatic alkenes has been presented here. This reaction employs ferric chloride （FeC13） as the CI source and the Langlois reagent （CF3SO2Na） as the CF3 source. It provides a convenient pathway towards a wide range of chlorotrifluoromethylated compounds.

关键词： chlorotrifluoromethylation alkene Langlois reagent radical

Design and concise synthesis of gem-difluoromethylenated analogue of 7-epi-castanospermine

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Chinese Chemical Letters 2014年第8期25卷 1115-1120页

作者： Xin-Yi Jiang xiu-Hua Xu Feng-Ling qing Key Laboratory of Organofluorine Chemistry Shanghai Institute of Organic Chemistry Chinese Academy of Science College of Chemistry Chemical Engineering and Biotechnology Donghua University

A novel gem-difluoromethylenated castanospermine analogue B was designed and synthesized, starting from 3-bromo-3,3-difluoropropene and L-（-）-malic acid. The key steps involve substitution cyclization reaction and R... 详细信息

关键词： lndolizidine Castanospermine gem-Difluoromethylene Cyclization Dihydroxylation

Effects of Exogenous Silicon on Photosynthetic Capacity and Antioxidant Enzyme Activities in Chloroplast of Cucumber Seedlings Under Excess Manganese

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Agricultural Sciences in China 2009年第1期8卷 40-50页

作者： FENG Jian-peng SHI qing-hua WANG xiu-feng College of Horticultural Science and Engineering Shandong Agricultural University Tai＇an 271018 P.R.China State Key Laboratory of Crop Biology Tai＇an 271018 P.R.China

Effects of silicon on photosynthetic parameters and antioxidant enzymes of chloroplast in cucumber seedlings under excess Mn were studied. Compared with the control, excess Mn significantly inhibited net photosynthetic rate （Pn）, stomatal conductance, as well as the maximum yield of the photosystem II photochemical reactions （Fv/Fm） and the quantum yield of photosysytem II electron transport （Φ PSII）, application of Si reversed the negative effects of excess Mn. In the further investigation, it was obtained that application of Si significantly increased the activities of enzymes related with ascorbate-glutathione cycle including ascorbate peroxidase （APX）, dehydroascorbate reductase （DHAR） and glutathione reductase （GR） in cucumber chloroplast under excess Mn, this could be responsible for the lower accumulation of H2O2 and lower lipid peroxidation of chloroplast induced by Mn, and resulted in keeping higher photosynthesis.

关键词： cucumber excess manganese photosynthesis chlorophyll fluorescence chloroplast antioxidant enzymes

Mathematical model of the direct reduction of dust composite pellets containing zinc and iron

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International Journal of Minerals,Metallurgy and Materials 2013年第7期20卷 627-635页

作者： xiu-wei An Jing-song Wang Xue-feng She qing-guo Xue State Key Laboratory of Advanced Metallurgy University of Science and Technology Beijing School of Metallurgical and Ecological Engineering University of Science and Technology Beijing School of Mechanical Engineering University of Science and Technology Beijing

Direct reduction of dust composite pellets containing zinc and iron was examined by simulating the conditions of actual production process of a rotary hearth furnace （RHF） in laboratory. A mathematical model was constructed to study the reduction kinetics of iron oxides and ZnO in the dust composite pellets. It was validated by comparing the calculated values with experimental results. The effects of furnace temperature, pellet radius, and pellet porosity on the reduction were investigated by the model. It is shown that furnace temperature has obvious influence on both of the reduction of iron oxides and ZnO, but the influence of pellet radius and porosity is much smaller. Model calculations suggest that both of the reduction of iron oxides and ZnO are under mixed control with interface reactions and Boudouard reaction in the early stage, but only with interface reactions in the later stage.

关键词： rotary hearth furnaces dust zinc ore pellets direct reduction process mathematical models kinetics