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Effect of slag composition on kinetic behavior of deep deoxidation of 5 wt.% Si high-silicon austenitic stainless steel

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Journal of Iron and Steel Research International 2024年第8期31卷 1873-1885页

作者： Guan-xiong Dou Han-jie Guo Jing Guo Xue-cheng Peng qing-yun chen School of Metallurgical and Ecological Engineering University of Science and Technology Beijing(USTB)Beijing 100083China Beijing Key Laboratory of Special Melting and Preparation of High-End Metal Materials Beijing 100083China

Based on a thermodynamic study of 5 wt.%Si high-silicon austenitic stainless steel(SS-5Si)smelting using CaF_(2)-CaO-Al_(2)0_(3)-Mg-Si0_(2) slag to obtain a low oxygen content of less than 10×10^(-4) wt.%,a kinetic mass transfer model for deep deoxidation was established through laboratory studies,and the effects of slag components and temperature on deoxidation during the slag-steel reaction process of sS-5Si were systematically *** experimental data verified the accuracy of the model *** results showed that the final oxygen content in the steel at 1873 K was mainly controlled by the oxygen content derived from the activity of SiO_(2) regulated by the[Si]-[O]equilibrium reaction in the slag system;in particular,when the slag basicity R(R=w(CaO)/w(SiO2),where w(CaO)and w(SiO_(2))are the contents of CaO and SiO_(2) in the slag,respectively)is 3,the Al2O3 content in the slag needs to be less than 2.7%.The mass transfer rate equation for the kinetics of the deoxidation reaction revealed that the mass transfer of oxygen in the liquid metal is the rate-controlling step under different slag conditions at 1873 K,and the oxygen transfer coefficient ko.m increases with increasing the slag basicity from 4.0×10^(-6)m s^(-1)(R=1)to 4.3×10^(-5) m s^(-1)(R=3).ko.m values at R=2 and R=3 are almost the same,indicating that high slag basicity has little *** integral of the mass transfer rate equation for the deoxidation reaction of SS-5Si under different slag conditions is *** total oxygen content of the molten steel decreases with increasing basicity from an initial content of 22×10^(-4) to 3.2×10^(-4) wt.%(R=3),consistent with the change in ko.m with slag *** R=2,the slag-steel reaction takes 15 min to reach equilibrium(w[O]=5.5×10^(-4) wt.%),whereas at R=3,the slag-steel reaction takes 30 min to reach equilibrium(w[0]=3.2×10^(-4) wt.%).Considering the depth of deoxidation and reaction time of SS-5Si smelting,it is recommended the slag b

关键词： Slag-steel reaction Kinetics Rate-controlling step Deep deoxidation Transfer coefficient

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Deoxyfluorination of Carboxylic, Sulfonic, Phosphinic Acids and Phosphine Oxides by Perfluoroalkyl Ether Carboxylic Acids Featuring CF_(2)0 Units

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Chinese Journal of Chemistry 2021年第5期39卷 1225-1232页

作者： Shiyu Zhao Yong Guo Zhaoben Su chengying Wu Wei chen qing-yun chen Key Laboratory of Orgonofluorine Chemistry Shanghai Institute of Organic ChemistryChinese Academy of Sciences345 Lingling RoadShanghai 200032China Sanming Hexafluo Chemicals Company Ltd.Fluorinated New Material Industry ParkMingxiSanmingFujian 365200China University of Chinese Academy of Sciences Beijing 100049China

The deoxyfluorination of carboxylic,sulfonic,phosphinic acids and phosphine oxides is a fundamentally important approach to access acyl fluorides,sulfonyl fluorides and phosphoric fluorides,thus the development of inexpensive,stable,easy-to-handle,versatile,and efficient deoxyfluorination reagents is highly ***,we report the use of potassium salts of perfluoroalkyl ether carboxylic acids(PFECA)featuring CF_(2)0 units as deoxyfluorination reagents,which are generated mainly as by-products in the manufacture of hexafluoropropene oxide(HFPO).The synthesis of acyl fluorides,sulfonyl fluorides and phosphoric fluorides can be realized via carbonic difluoride(COF_(2))generated in situ from thermal degradation of the PFECA salt.

关键词： Fluorine Fluorides Deoxyfluorination Perfluoroalkyl ether carboxylic acids Carboxylic acids

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Bronchoscopy for diagnosis of COVID-19 with respiratory failure:A case report

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World Journal of Clinical Cases 2021年第5期9卷 1132-1138页

作者： qing-yun chen Yu-Sheng He Kai Liu Jing Cao Yong-Xing chen Department of Respiratory and Critical Care Medicine Hainan General HospitalHaikou 570311Hainan ProvinceChina Department of Internal Medicine Hainan Province's Fucheng Drug Rehabilitation CentreHaikou 570311Hainan ProvinceChina Infection Department Hainan General HospitalHaikou 570311Hainan ProvinceChina

BACKGROUND Although the imaging features of coronavirus disease 2019(COVID-19)are starting to be well determined,what actually occurs within the bronchi is poorly ***,we report the processes and findings of bronchoscopy in a patient with COVID-19 accompanied by respiratory *** SUMMARY A 65-year-old male patient was admitted to the Hainan General Hospital on February 3,2020 for fever and shortness of breath for 13 d that worsened for the last 2 *** severe acute respiratory syndrome coronavirus 2 nucleic acid test was *** blood examination on February 28 showed a white blood cell count of 11.02×109/L,86.9%of neutrophils,6.4%of lymphocytes,absolute lymphocyte count of 0.71×109/L,procalcitonin of 2.260 ng/mL,and C-reactive protein of 142.61 mg/*** saturation was 46%at baseline and turned to 94%after *** patient underwent video *** tracheal cartilage ring was clear,and no deformity was found in the *** trachea and bilateral bronchi were patent,while the mucosa was with slight hyperemia;no neoplasm or ulcer was *** amounts of white gelatinous secretions were found in the dorsal segment of the left inferior lobe,and the bronchial lumen was patent after sputum *** right inferior lobe was found with hyperemia and mucosal erosion,with white gelatinous secretion *** patient’s condition did not improve after the application of therapeutic *** For patients with COVID-19 and respiratory failure,bronchoscopy can be performed under mechanical ventilation to clarify the airway *** should be worn during the *** the risk of infection,it is not necessary to perform bronchoscopy in the mild to moderate COVID-19 patients.

关键词： COVID-19 Respiratory failure Bronchoscopy Diagnosis Treatment Case report

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Catalyst-Free Hydroxytrifluoromethylation of Alkenes UsingIodotrifluoromethane

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Chinese Journal of Chemistry 2019年第1期37卷 597-604页

作者： Zhaoben Su Yong Guo qing-yun chen Zhi-Gang Zhao Bao-Yi Nian College of Chemistry & Environment Protection Engineering Southwest Minzu UniversityChengduSichuan 610041China Key Laboratory of Organofluorine Chemistry Shanghai Institute of Organic ChemistryChinese Academy of Sciencesand University of Chinese Academy of Sciences345 Lingling RoadShanghai 200032China Sanming Institute of Fluorochemical Industry Sanming UniversitySanmingFujian 365004China

The importance of CF3-containing molecules in pharmaceuticals, agrochemicals and materials intrigues the intense interest in synthetic methodology of these compounds. With a purpose to enrich trifluoromethylation methodology, we carefully examined the substrate scope of hydroxytrifluoromethylation of alkenes using iodotrifluoromethane, and the reaction provided β-trifluoromethyl alcohols in good yields under extremely mild conditions without catalysts. We found that our reaction can be applied to not only styrenes but also various aliphatic alkenes with excellent selectivity;no ketone was detected in most of our cases. Another feature of our discovery is “simple”. The reaction was carried out in air, irradiated by visible light, at room temperature and most importantly no catalyst was needed. A solution of CF3I in DMSO was used as the facile trifluoromethylating reagent, which simplified the utilization of gaseous CF3I. Based on 19F NMR spectroscopy, we observed a halogen bond between CF3I and tertiary amine in this reaction. The interaction may promote single electron transfer by the visible light irradiation.

关键词： trifluoromethyl catalyst-free hydroxylation alkenes photochemistry

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Atypical aggressive vertebral hemangioma of the sacrum with postoperative recurrence:A case report

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World Journal of Clinical Cases 2022年第34期10卷 12648-12653页

作者： Guan-Xi Wang yun-qing chen Yan Wang Chuan-Ping Gao Department of Radiology Songshan Hospital of Qingdao University Medical College UniversityQingdao 266000Shandong ProvinceChina Department of Pathology The Affiliated Hospital of Qingdao UniversityQingdao 266003Shandong ProvinceChina Department of Radiology The Affiliated Hospital of Qingdao UniversityQingdao 266003Shandong ProvinceChina

BACKGROUND Aggressive vertebral hemangioma(VH)is an uncommon lesion in the adult *** vast majority of aggressive VHs have typical radiographic ***,preoperative diagnosis of atypical aggressive VH may be *** VHs are likely to recur even with en bloc *** SUMMARY A 52-year-old woman presented with a 3-mo history of numbness and pain in her right lower *** examination showed sacral tenderness and limited mobility,and the muscle strength was grade 4 in the right digital *** tomography revealed osteolytic bone destruction from S1 to *** resonance imaging(MRI)showed that the mass was compressing the dural sac;it was heterogeneously hypointense on T1-weighted MRI and hyperintense on T2-weighted MRI,and gadolinium contrast enhancement showed that the tumor was heterogeneously enhanced and invading the vertebral endplate of *** patient developed progressive back pain and numbness in the bilateral extremities 6 mo postoperatively,and MRI examination showed recurrence of the *** mass was larger in size than before the operation,and it was extending into the spinal *** The radiographic findings of atypical aggressive VH include osteolytic vertebral bone destruction,extension of the mass into the spinal canal,and heterogeneous signal intensity on T1-,T2-,and enhanced T1-weighted *** characteristics make preoperative diagnosis difficult,and biopsy is necessary to verify the *** decompression and gross total resection are recommended for treatment of aggressive ***,recurrence is inevitable in some cases.

关键词： Vertebral hemangioma Aggressive Spine Computed tomography Magnetic resonance imaging Case report

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First Principles Study of Uranium Solubility in Gd2Zr2O7 Pyrochlore

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Chinese Journal of Chemical Physics 2015年第6期28卷 -页

作者： qing-yun chen Kai-min Shih Chuan-min Meng Lie-lin Wang Hua Xie Tao Wu Key Subject Laboratory of National Defense for Radioactive Waste and Environmental Security Southwest University of Science and Technology Mianyang 621010 China Department of Civil Engineering The University of Hong Kong Pokfulam Road Hong Kong SARChina Key Lab for Shock Wave and Detonation Physics Research Institute of Fluid Physics Chinese Academy of Engineering Physics Mianyang 621900

Ab initio calculation is performed to investigate the uranium solubility in different sites of Gd2Zr2O7 pyrochlore. The Gd2Zr2O7 maintains its pyrochlore structure at low uranium dopant levels, and the lattice constants of Gd2(Zr2?yUy)O7and (Gd2?yUy)Zr2O7are gen- erally expressed as being linearly related to the uranium content y. Uranium is found to be a preferable substitute for the B-site gadolinium atoms in cation-disordered Gd2Zr2O7 (where gadolinium and zirconium atoms are swapped) over the A-site gadolinium atoms in ordered Gd2Zr2O7due to the lower total energy of (Gd2yZry)(Zr2yUy)O7.

关键词： Gd2Zr2O7 pyrochlore Nuclear waste Uranium solubility Density functional theory

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PENTAFLUOROBENZENESULFONYL BROMIDE AND ITS REACTIONS

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Chinese Chemical Letters 1991年第8期2卷 597-600页

作者： qing yun chen Ming Fang chen Shanghai Institute of Organic Chemistry Chinese Academy of SciencesShanghai 200032

Pentafluorobenzenesulfonyl bromide was synthesized by the reaction of pentafluorophenylmagnesium chloride with sulphur dioxide followed by bromine oxidation. The sulfonyl bromide reacted with polyfluorophenoxide to form polyfluorophenyl pentafluorobenzenesulfonates. Photolysis of pentafluorobenzenesulfonyl bromide gave bis(pentafluorobenzene)sulfone and decafluorodiphenyl.

关键词： THF SO PENTAFLUOROBENZENESULFONYL BROMIDE AND ITS REACTIONS chen FSS ITS

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Aliphatic sulfonyl fluoride synthesis via reductive decarboxylative fluorosulfonylation of aliphatic carboxylic acid NHPI esters

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Organic Chemistry Frontiers 2022年第4期9卷 1115-1120页

作者： Zhanhu Ma Yongan Liu Xiaoyu Ma Xiaojun Hu Yong Guo qing-yun chen Chao Liu School of Chemical and Environmental Engineering Shanghai Institute of Technology100 Haiquan RoadShanghai 201418China Key Laboratory of Organofluorine Chemistry Shanghai Institute of Organic ChemistryUniversity of Chinese Academy of SciencesChinese Academy of Sciences345 Lingling RoadShanghai 200032China

Based on a radical sulfur dioxide insertion and fluorination strategy,we have developed an efficient method for aliphatic sulfonyl fluoride synthesis using abundant carboxylic acids,a reductant,a sulfur dioxide surrogate and the electrophilic fluorination reagent N-fluorobenzenesulfonimide(NFSI)under reduction *** protocol provides a convenient synthetic pathway for various aliphatic sulfonyl fluorides and tolerates a wide range of functional groups.

关键词： conditions fluoride synthesis

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RiceDB:A Web-Based Integrated Database for Annotating Rice Microarray

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Rice science 2007年第4期14卷 256-264页

作者： HE Fei SHI qing-yun chen Ming WU Ping State Key Laboratory of Plant Physiology ＆ Biochemistry College of Life Sciences Zhejiang University Hangzhou 3100584 China

RiceDB, a web-based integrated database to annotate rice microarray in various biological contexts was developed. It is composed of eight modules. RiceMap module archives the process of Affymetrix probe sets mapping to different databases about rice, and aims to the genes represented by a microarray set by retrieving annotation information via the identifier or accession number of every database; RiceGO module indicates the association between a microarray set and gene ontology （GO） categories; RiceKO module is used to annotate a microarray set based on the KEGG biochemical pathways; RiceDO module indicates the information of domain associated with a microarray set; RiceUP module is used to obtain promoter sequences for all genes represented by a microarray set; RiceMR module lists potential microRNA which regulated the genes represented by a microarray set; RiceCD and RiceGF are used to annotate the genes represented by a microarray set in the context of chromosome distribution and rice paralogous family distribution. The results of automatic annotation are mostly consistent with manual annotation. Biological interpretation of the microarray data is quickened by the help of RiceDB.

关键词： Affymetrix microarray annotation Oryza sativa molecular database

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Recent catalytic syntheses of trifluoromethylthio-containing organic compounds by transition metals,chiral organocatalysts,and photocatalysts

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Chinese Chemical Letters 2017年第4期28卷 719-728页

作者： Yong Guo Mei-Wei Huang Xiao-Lin Fu Chao Liu qing-yun chen Zhi-Gang Zhao Ben-Zhong Zeng Jiong chen Key Laboratory of Organofluorine Chemistry Shanghai Institute of Organic Chemistry Chinese Academy of Sciences Shanghai 200032 China College of Chemistry and Environment Protection Engineering Southwest University for Nationalities Chengdu 610041 China Zhonghao chenguang Research Institute of Chemical Industry Zigong 643201 China

This review summarizes the recent advances in the catalytic syntheses of CFS-containing organic molecules using various nucleophilic or electrophilic trifluoromethylthiolating reagents.C-halogen and C—H bonds in various molecules have been transformed to C—SCFbonds by transition-metal-catalyzed reactions,such as cross-coupling of aryl *** reactions controlled by chiral metal complexes or chiral organocatalysts have afforded many trifluoromethylthiolated chiral architectures,such as β-ketoesters and *** recently,visible-light-induced photoredox trifluoromethylthiolations have been developed,providing versatile CFS-containing structures efficiently.

关键词： Trifluoromethylthiolation Catalysis Transition metal Chiral Photoredox

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