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Nickel-Catalyzed Electroreductive Syntheses of Triphenylenes Using ortho-Dihalobenzene-Derived Benzynes

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Chinese Journal of Chemistry 2022年第19期40卷 2335-2344页

作者： Zhao-Ming Li Bin Shuai cong Ma Ping fang Tian-Sheng Mei State Key Laboratory of Organometallic Chemistry Center for Excellence in Molecular SynthesisShanghai Institute of Organic ChemistryUniversity of Chinese Academy of SciencesChinese Academy of Sciences345 Lingling RoadShanghai200032 China

Electrochemical nickel-catalyzed syntheses of triphenylenes by a)reductive trimerization of ortho-dibromobenzenes or ortho-bromoarylsulfurofluoridates,or b)reductive cross-coupling of ortho-dibromobenzenes to 2,2’-diiodobiphenyls,are described.The former provides a practical means for the construction of triphenylene derivatives in up to 87%isolated yield at room temperature.For 1,2-dihalo-3-methylbenzenes and related ortho-trisubstituted substrates,trimerizations proceed with high substrate-controlled regioselectivity for the non-C3h symmetric triphenylene isomer.

关键词： Electrochemistry Ni catalysis Benzyne Cyclotrimerization Cross coupling

Single-metal-atom site with high-spin state embedded in defective BN nanosheet promotes electrocatalytic nitrogen reduction

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Nano Research 2021年第11期14卷 4211-4219页

作者： cong fang Wei An College of Chemistry and Chemical Engineering Shanghai University of Engineering ScienceShanghai201620China

Single-atom catalysts (SACs) especially supported on two-dimensional nitrogen-doped carbon substrate have been widely reported to be able to effectively promote electrocatalytic N_(2) reduction reaction (eNRR). The precise design of single-metal-atom active site (SMAS) calls for fundamental understanding of its working mechanism for enhanced eNRR performance. Herein, by means of density functional theory calculations, we theoretically investigate the eNRR performance of nine prototypical SMAS, namely, MN_(2)B_(2) (M: transition metals of IIIB, IVB and VB groups) which comprises of asymmetric ligands of N_(2)B_(2) embedded in defective BN nanosheet. Our results reveal the significant role of spin state of SMAS in tuning the potential-determining steps of eNRR, in which MN_(2)B_(2) site with higher spin magnetic moment (μ) is beneficial to reducing limiting potentials (U_(L)) of eNRR. Specially, CrN_(2)B_(2) (μ = 4μB), VN_(2)B_(2) (μ = 3μB) and MoN_(2)B_(2) (μ = 2μB) demonstrate high activity and selectivity to eNRR. The asymmetric ligands of N_(2)B_(2) are deemed to be superior over mono-symmetric ligands. More importantly, our results demonstrate that breaking (or deviating) of the scaling relations between key N-containing intermediates (*N_(2)H/*N_(2) and *NH2/*N_(2)) on MN_(2)B_(2) can be realized by enhancing spin state of SMAS which renders the active site a balanced N-affinity critical for efficient eNRR. This observation is validated by the calculated Sabatier volcano-shape relation between eNRR limiting potentials and N_(2) adsorption energy. Our study develops the guidance for catalyst design to boost eNRR performance by tuning the spin state of an active site.

关键词： electrocatalysis N_(2)reduction BN nanosheet spin state single-atom catalyst jdensity functional theory(DFT)

Divergent synthesis of aryl amines and dihydroquinazolinones via electrochemistry-enabled rhodium-catalyzed C–H functionalization

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中国科学:化学英文版 2023年第10期66卷 2863-2870页

作者： Yi-Kang Xing Zhen-Hua Wang Ping fang cong Ma Tian-Sheng Mei State Key Laboratory of Organometallic Chemistry Shanghai Institute of Organic ChemistryUniversity of Chinese Academy of SciencesShanghai 200032China

Electrochemistry-enabled rhodium-catalyzed C–H amination and amination cyclization of arene assisted by a weakly coordinating amide have been reported. Additionally, aryl amines and dihydroquinazolinones could be obtained selectively by controlling the electric current. Mechanistic studies suggested that the amination reaction likely involves an electrochemical oxidation-induced reductive elimination of a high valent rhodium intermediate, which led to the amination reaction even proceeding smoothly at room temperature.

关键词： organic electrochemistry rhodium catalysis C-H functionalization divergent synthesis

Process intensification and energy saving of reactive distillation for production of ester compounds

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Chinese Journal of Chemical Engineering 2019年第6期27卷 1307-1323页

作者： Chunli Li cong Duan Jing fang Hongshi Li School of Chemical Engineering and Technology Hebei University of TechnologyTianjin 300130China National-Local Joint Engineering Laboratory for Energy Conservation of Chemical Process Integration and Resources Utilization Tianjin 300130China

Reactive distillation(RD) process is an innovative hybrid process combining reaction with distillation, which has recently come into sharp focus as a successful case of process intensification. Considered as the most representative case of process intensification, it has been applied for many productions, especially for production of ester compounds. However, such problems existing in the RD system for ester productions are still hard to solve,as the removal of the water which comes from the esterification, and the separation of the azeotropes of ester–alcohol(–water). Many methods have been studying on the process to solve the problems resulting in further intensification and energy saving. In this paper, azeotropic–reactive distillation or entrainer enhanced reactive distillation(ERD) process, reactive extractive distillation(RED) process, the method of co-production in RD process, pressure-swing reactive distillation(PSRD) process, reactive distillation–pervaporation coupled process(RD–PV), are introduced to solve the problems above, so the product(s) can be separated efficiently and the chemical equilibrium can be shifted. Dividing-wall column(DWC) structure and novel methods of loading catalyst are also introduced as the measures to intensify the process and save energy.

关键词： Reactive distillation Process intensification Process coupling Thermal coupling

Light control of droplets on photo-induced charged surfaces

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National Science Review 2023年第1期10卷 259-267页

作者： fang Wang Meijin Liu cong Liu Chao Huang Lidong Zhang Anyang Cui Zhigao Hu Xuemin Du Institute of Biomedical and Health Engineering Shenzhen Institute of Advanced TechnologyChinese Academy of Sciences University of Chinese Academy of Sciences Department of Chemistry and Molecular Engineering East China Normal University Technical Center for Multifunctional Magneto-Optical Spectroscopy(Shanghai) Engineering Research Center of Nanophotonics and Advanced Instrument(Ministry of Education)Department of Physics School of Physics and Electronic Science East China Normal University

The manipulation of droplets plays a vital role in fundamental research and practical applications,from chemical reactions to bioanalysis.As an intriguing and active format,light control of droplets,typically induced by photochemistry,photomechanics,light-induced Marangoni effects or light-induced electric fields,enables remote and contactless control with remarkable spatial and temporal accuracy.However,current light control of droplets suffers from poor performance and limited reliability.Here we develop a new superamphiphobic material that integrates the dual merits of light and electric field by rationally preparing liquid metal particles/poly(vinylidene fluoride-trifluoroethylene) polymer composites with photo-induced charge generation capability in real time,enabling light control of droplets on the basis of photo-induced dielectrophoretic force.We demonstrate that this photo-induced charged surface(PICS)imparts a new paradigm for controllable droplet motion,including high average velocity(～35.9 mm s-1),unlimited distance,multimode motions(e.***.forward,backward and rotation) and single-to-multiple droplet manipulation,which are otherwise unachievable in conventional strategies.We further extend light control of droplets to robotic and bio-applications,including transporting a solid cargo in a closed tube,crossing a tiny tunnel,avoiding obstacles,sensing the changing environment via naked-eye color shift,preparing hydrogel beads,transporting living cells and reliable biosensing.Our PICS not only provides insight into the development of new smart interface materials and microfluidics,but also brings new possibilities for chemical and biomedical applications.

关键词： light control droplet manipulation smart surface liquid metal ferroelectric

Clinical Characteristics,Diagnosis,and Therapeutics of COVID-19:A Review

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Current Medical Science 2023年第6期43卷 1066-1074页

作者： Na-na XIE Wen-cong ZHANG Jia CHEN fang-bing TIAN Jian-xin SONG Department of Infectious Diseases Tongji HospitalTongji Medical CollegeHuazhong University of Science and TechnologyWuhan430030China

The novel severe acute respiratory syndrome coronavirus 2(SARS-CoV-2)that suddenly emerged at the end of December 2019 and caused coronavirus disease 2019(COVID-19)continues to afflict humanity,not only seriously affecting healthcare systems but also leading to global social and economic imbalances.As of August 2022,there were approximately 580 million confirmed cases of COVID-19 and approximately 6.4 million confirmed deaths due to this disease.The data are sufficient to highlight the seriousness of SARS-CoV-2 infection.Although most patients with COVID-19 present primarily with respiratory symptoms,an increasing number of extrapulmonary systemic symptoms and manifestations have been associated with COVID-19.Since the outbreak of COVID-19,much has been learned about the disease and its causative agent.Therefore,great effort has been aimed at developing treatments and drug interventions to treat and reduce the incidence of COVID-19.In this narrative review,we provide a brief overview of the epidemiology,mechanisms,clinical manifestations,diagnosis,and therapeutics of COVID-19.

关键词： coronavirus disease 2019 severe acute respiratory syndrome coronavirus 2 mechanism clinical manifestations diagnosis therapeutics

Clinical application of the endometrial microbiota test combined with personalized treatment in patients with repeated implantation failure

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生殖与发育医学(英文) 2024年第1期08卷 18-23页

作者： Chen Rou-Zhu Wang Yan-fang Chen Pei-Gen fanG Cong Li Ting-Ting Reproductive Medicine Center The Sixth Affiliated Hospital 3. Sun Yat-sen University 4. Guangzhou 510655 5. China

Objective: The objective of this study was to investigate the clinical value of the endometrial microbiota test (EMT) combined with personalized treatment in patients with repeated implantation failure (RIF).Methods: From March 2019 to August 2022, the clinical data of patients with RIF at the Reproductive Medicine Research Center of the Sixth Affiliated Hospital of Sun Yat-sen University were retrospectively analyzed. A total of 356 patients underwent the EMT using 16S rRNA sequencing and were included in the EMT group. The SPSS statistical software propensity score was set at 1:1 to match the age, anti-Müllerian hormone (AMH), antral follicle count (AFC), years of infertility, and body mass index (BMI) of the women who had not undergone the EMT; subsequently, 354 patients were classified in the non-EMT group. We compared the clinical characteristics of the two groups and analyzed the clinical pregnancy outcomes after personalized treatment.Results: The clinical pregnancy rate (CPR) of the EMT group was significantly higher than that of the non-EMT group (47.81%vs. 13.38%,P <0.05). Among 356 patients who underwent the EMT, 55 patients (15.45%) in group A with normal endometrial microbiota composition did not test positive for the pathogenic bacteria causing chronic endometritis, 34 patients (9.55%) in group B with abnormal endometrial microbiota composition did not test positive for the pathogenic bacteria causing chronic endometritis, 35 patients (9.83%) in group C with normal endometrial microbiota composition tested positive for the pathogenic bacteria causing chronic endometritis, and 232 patients (65.17%) in group D with abnormal endometrial microbiota composition tested positive for the pathogenic bacteria causing chronic endometritis. After administration of probiotics or antibiotic plus probiotics treatment, the pregnancy rates of groups C and D were higher than those of group A (44.00%vs. 20.00% and 55.03%vs. 20.00%, respectively; bothP <0.05).Conclusion: The EMT combined with personalized treatment in

关键词： Endometrial microbiota test Assisted reproductive technology Repeated implantation failure Personalized treatment

The Crystallization Behavior and Stability of Chromite Synthesized in Chromium-Containing Wastewater at Room Temperature

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Engineering 2022年第2期8卷 67-76页

作者： Jin-fang Lv Ying-cong Quan Xiong Tong Yongjun Peng Yong-Xing Zheng Faculty of Land Resource Engineering Kunming University of Science and TechnologyKunming 650093China State Key Laboratory of Complex Nonferrous Metal Resources Clean Utilization Kunming University of Science and TechnologyKunming 650093China School of Chemical Engineering The University of QueenslandBrisbaneQLD 4072Australia

The ferrite process can not only purify wastewater containing heavy metal ions but also recycle valuable metals from wastewater. Therefore, it is considered a promising technology to treat chromiumcontaining wastewater. However, the process has not been extensively applied in industry due to its high synthesis temperature. In this paper, the feasibility of chromite synthesis at room temperature was comprehensively studied. The effects of critical factors on the effluent quality and the crystallization behavior and stability of the synthetic products were investigated. Results showed that the removal ratio of chromium from wastewater was over 99.0%, and the chromium concentration in the supernatant reached the sewage discharge standard after undergoing the ferrite process at room temperature. Increases in the aeration rate, stirring rate, and reaction time were favorable for the formation of stable chromite. The particles obtained by the ferrite process at room temperature were characterized by a compact structure, and the maximum size of the particles reached 52 μm. Chromium gradually entered the spinel crystal structure during the synthesis process, and the molecular formula of the synthetic chromite might be Fe3-xCrxO4, in which x was approximately 0.30. The path of the microscopic reaction was proposed to illuminate the synthesis mechanism of chromite under room temperature conditions. The present study has laid the foundation for the industrial application of the ferrite process in the purification and utilization of chromium-containing wastewater.

关键词： Chromium-containing wastewater Synthesis of chromite Room temperature Crystallization behavior Stability

Multi-performance evaluation of high-throughput accelerated corrosion test for high-strength low-alloy 921A steel

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JOURNAL OF IRON AND STEEL RESEARCH INTERNATIONAL 2023年第5期31卷 1260-1278页

作者： Du, cong-cong Qin, Ming-hua Wu, Zhan-fang Li, Dong-ling Zhao, Lei Li, Xiang-yang Wang, Hai-zhou Univ Sci & Technol Beijing Beijing Adv Innovat Ctr Mat Genome Engn Natl Ctr Mat Serv Safety Beijing 100083 Peoples R China Cent Iron & Steel Res Inst Beijing Adv Innovat Ctr Mat Genome Engn Beijing 100081 Peoples R China China Iron & Steel Res Inst Grp Co Ltd Beijing 100081 Peoples R China

The corrosion behavior of high-strength low-alloy 921A steel in a simulated marine atmospheric environment was studied using a high-throughput experimental method. The corrosion behavior, corrosion morphology, and corrosion products of 921A steels were analyzed using various techniques, including corrosion mass loss method, polarization curve, white-light interferometry, scanning electron microscopy, energy-dispersive spectrometry, microbeam X-ray fluorescence spectrometry, X-ray diffraction technique, and X-ray photoelectron spectroscopy. The test results indicated that 921A steel exhibits better corrosion resistance than Q450NQR1 steel in simulated harsh atmospheric environments, as evidenced by a lower corrosion mass loss rate throughout the corrosion tests. The corrosion products of both steels consisted of alpha-FeOOH, Fe3O4, and gamma-FeOOH, with alpha-FeOOH being more prevalent in the rust layer of 921A steel than in Q450NQR1 steel. The inner rust layer of 921A steel also exhibited an appositional enrichment region of Cr, Ni, Mo, and V, leading to its superior corrosion resistance compared to that of Q450NQR1 steel. The efficacy of high-throughput accelerated corrosion experimental methods was highlighted for evaluating the corrosion resistance of steel materials in harsh environmental conditions. The findings suggest that 921A steel exhibits better corrosion resistance compared to Q450NQR1 steel and has the potential to be more suitable in harsh marine atmospheric environments. The characterization of the rust layer structures and composition reveals the parallel enrichment of certain elements in the inner rust layer of 921A steel, which enhances its corrosion resistance.

关键词： Atmospheric corrosion High-throughput experimental method High-strength low-alloy steel Corrosion characteristics Rust layer Element enrichment CARBON-STEEL ATMOSPHERIC-CORROSION WEATHERING STEEL RUST LAYERS BEHAVIOR MARINE CR NI CU