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Copper-Catalyzed Asymmetric Three-Component Radical 1,2-Carboamination of Acrylamides with Arylamines: Access to Chiral α-Tertiary N-Arylamines

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CCS Chemistry 2024年第11期6卷 2652-2661页

作者： Jia-Heng Fang Ji-Jun Chen Xuan-Yi Du Zhe Dong run-yan tian Chang-Jiang yang Fu-Li Wang Cheng Luan Zhong-Liang Li Xin-Yuan Liu School of Chemistry and Chemical Engineering Harbin Institute of TechnologyHarbin 150001 Shenzhen Grubbs Institute Department of ChemistryGuangming Advanced Research InstituteShenzhen Key Laboratory of CrossCoupling ReactionsSouthern University of Science and TechnologyShenzhen 518055 Department of Chemistry and Dongguan Key Laboratory for Data Science and Intelligent Medicine Great Bay UniversityDongguan 523000 Dongguan Key Laboratory of Interdisciplinary Science for Advanced Materials and Large-Scale Scientific Facilities School of Physical SciencesGreat Bay UniversityDongguan 523000

The asymmetric radical carboamination of 1,1-disubstituted alkenes from readily available alkyl halides and arylamines provides expedient access to valueadded chiralα-tertiary N-arylamines but has been less recognized.A challenge arises mainly from the difficult reaction initiation inherent in alkyl halides and the construction of fully substituted chiral C–N bonds from sterically congested tertiary alkyl ***,we report a copper-catalyzed asymmetric three-component radical carboamination of acrylamides utilizing an anionic chiral N,N,N-ligand under mild *** ligand was essential for the reaction initiation by enhancing the reducing capability of copper and enabling the enantiocontrol over tertiary alkyl *** substrate scope was broad,covering an array of acrylamides,aryl-and heteroaryl-amines,as well as alkyl halides and sulfonyl chlorides,enabling good functional group *** combined with the follow-up transformation,this strategy provides a versatile platform for accessing structurally diverse chiralα-tertiary N-arylamine building blocks of interest in organic synthesis.

关键词： asymmetric catalysis copper alkenes radical reactions chiral amines

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Advances in ethnopharmacology,phytochemistry and pharmacology of Erigerontis Herba and its Chinese medicine prescriptions

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Traditional Medicine Research 2025年第1期10卷 44-61页

作者： yang Zhou Yuan-yan Huang Ding-Yue Shang Ying Chen Meng tian Cheng-Yu Jin Xin Lu Bing-Chun yan Han-Qing Pang Institute of Translational Medicine School of MedicineYangzhou UniversityYangzhou 225009China Jiangsu Key Laboratory of Integrated Traditional Chinese and Western Medicine for Prevention and Treatment of Senile Diseases Yangzhou UniversityYangzhou 225009China School of Medicine Nanjing University of Chinese MedicineNanjing 210023China State Key Laboratory for Chemistry and Molecular Engineering of Medicinal Resources Guangxi Normal UniversityGuiling 541004China.

Erigerontis Herba(EH),the dried whole plant of Erigeron breviscapus,is well-known for circulating blood,activating meridians to alleviate pain,expelling wind,and clearing away *** has been extensively utilized in southern China for the treatment of stroke hemiplegia,chest stuffiness and pains,rheumatic arthralgia,headache,and *** review focuses on the botany,ethnopharmacology,phytochemistry,pharmacology and toxicity of EH and its related prescriptions to offer new insights for prospective research of *** information about EH was retrieved from ancient records and books,PubMed,China National Knowledge Infrastructure,Chinese Pharmacopoeia,Web of Science,Doctoral and Master’s Theses,and various electronic *** is a member of Compositae family and is mainly grown in southern *** Chinese medicine records that EH has the effects of circulating blood and removing blood stasis,expelling wind,and removing cold,as well as relieving rigidity of muscle and relieving *** now,nearly 200 ingredients have been characterized from EH,including flavonoids,caffeoyls,aromatic acids,coumarins,pentacyclic terpenoids,volatile oil and other *** extracts,EH related prescriptions(Dengzhan Xixin injection,Dengzhan Shengmai capsules,etc.)or compounds(scutellarin,scutellarein,etc.)possessed obvious therapeutic effects of ischemic stroke,cerebral hemorrhage,myocardial infarction,Alzheimer’s disease,diabetes and its complications,gastric cancer,bone,and joint degenerative ***,the major active compound of EH,has been used as a quality *** no obvious toxicity of EH has been *** to its traditional applications,ethnopharmacology,phytochemistry,pharmacology,and toxicity,EH was applied as a valuable herb for clinical application in food and medicine *** several compounds have been shown to possess diverse biological activities,the underlying mechanisms of their actions remain *** fully exploi

关键词： Erigeron breviscapus traditional applications ethnopharmacology phytochemistry pharmacology

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Computational analysis of fluid-structure interaction in case of fish swimming in the vortex street

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Journal of Hydrodynamics 2021年第4期33卷 747-762页

作者： Lang yan Xing-hua Chang Nian-hua Wang run-yu tian Lai-ping Zhang Wei Liu College of Aerospace Science and Engineering National University of Defense TechnologyChangsha410073China Unmanned Systems Research Center National Innovation Institute of Defense TechnologyBeijing100071China China Aerodynamics Research and Development Center State Key Laboratory of AerodynamicsMianyang621000China Hypervelocity Aerodynamics Institute China Aerodynamics Research and Development CenterMianyang621000China

The fluid-structure interaction (FSI) in case of fish swimming in the vortex street is investigated by numerical simulations. The vortex street is generated by a D-section cylinder. A 2-D fish model is placed on the downstream centerline of the bluff cylinder at a distance of 4 diameters away from the center of the cylinder. To simulate the fish body undulation and movement, the moving mesh is generated by a coupling approach based on the radial basis function and the overset grid technology. The Navier-Stokes equation in the arbitrary Lagrangian-Eulerian form is solved by coupling with the kinematics equation. Three cases are investigated: in a stationary position without deformation, a passive locomotion without deformation, and an active deformation based on the Kármán gait model. The results indicate that the fish body is acted by an alternating force and moment when it is located in the centerline of the vortex street. Furthermore, the fish could extract sufficient kinetic energy to overcome the drag under suitable conditions even when it keeps rigid and out of the suction zone. When the fish body undulates based on the Kármán gait model, the interaction is evidently shown between the fish body and the vortices. The theoretical analysis demonstrates that the lateral force and the moment acting on the fish body vary in a cosine formula, with the lateral translation and the body rotation as a result. This study focuses on the behavior of the fish body in the bluff cylinder wake and reproduces some phenomena observed in the experiments. Besides, the Kármán gait model is also theoretically analyzed, for the further exploration of the FSI mechanism in case of fish swimming.

关键词： Computational analysis fluid-structure interaction(FSI) Kármán gait vortex street passive locomotion fish swimming

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Modified frontolateral partial laryngectomy operation: combined muscle-pedicle hyoid bone and thyrohyoid membrane flap in laryngeal reconstruction

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Cancer Biology & Medicine 2013年第2期10卷 103-109页

作者： Dian Ouyang tian-run Liu yan-Feng Chen Jian Wang Key Laboratory of Oncology in Southern China Department of Head and Neck Sun Yat-sen University Cancer Center Department of Otorinolaryngology Head and Neck Surgery The Sixth Affiliated Hospital of Sun Yat-sen University Department of Anesthesia Sun Yat-Sen University Cancer Center

Objective: Laryngeal reconstruction is needed to preserve laryngeal function in patients who have undergone extensive vertical or frontal partial laryngectomy. However, the procedure remains a difficult challenge. Several reconstruction techniques have been described, but these techniques pose risks of complications such as laryngeal stenosis. This study aimed to evaluate the postoperative course and functional outcomes of a new technique that combined a muscle-pedicle hyoid bone and a thyrohyoid flap during laryngeal reconstruction after tumor resection. Methods: Four patients underwent extensive vertical partial or frontal partial laryngectomy for cancer. After tumor resection, laryngeal reconstruction was performed using the proposed technique. Postoperative recovery time, complications, and oncologic results were evaluated. Results: The four patients were successfully treated with the proposed technique. No dyspnea, dysphagia, or death occurred during the postoperative course. Decannulation was performed after a median of 3 days. The average postoperative hospital stay was 7 days. Short-term postoperative functional recovery was normal. No laryngeal stenosis or tumor recurrence was observed in any of the four patients after a follow-up period of more than 24 months. Conclusion: The combination of the muscle-pedicle hyoid bone and the thyrohyoid flap is a reliable procedure for laryngeal reconstruction after extensive vertical partial or frontal partial laryngectomy.

关键词： Hyoid bone reconstruction laryngeal cancer flap operation

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美丽园区建设的路径研究

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生态经济 2025年第1期41卷 44-51页

作者：陈吕军严坤田金平清华大学环境学院北京100084 清华大学生态文明研究中心北京100084 清华大学碳中和研究院北京100084

建设美丽中国是全面建设社会主义现代化国家、实现中华民族永续发展的重要举措。中国工业园区历经四十多年发展历程,已经成为建设实体经济、引领区域发展的先行者,目前已聚集全国80%的工业企业,推动工业园区建设成为人与自然和谐共生的... 详细信息

建设美丽中国是全面建设社会主义现代化国家、实现中华民族永续发展的重要举措。中国工业园区历经四十多年发展历程,已经成为建设实体经济、引领区域发展的先行者,目前已聚集全国80%的工业企业,推动工业园区建设成为人与自然和谐共生的美丽园区,对我国生态文明建设意义重大。论文回顾了中国工业园区的发展历程,面向新发展阶段存在的新挑战和新机遇,提出了工业园区在新时代需承担的高质量发展使命任务。在此基础上,本文针对园区社会、经济、自然三个子系统,从六个方面解析并详细阐述了中国工业园区打造美丽园区、支撑美丽中国建设的关键内涵。进一步地,根据国家对美丽中国建设提出的目标和计划,结合我国生态工业园区发展过程中形成的实践经验,从八个维度提出工业园区推进美丽中国建设的关键行动,支撑工业园区生态文明建设和美丽中国行动。

关键词：美丽中国工业园区美丽园区绿色发展生态文明

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The“harmful algae and algal toxins in coastal waters of China:investigation and database”project

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Journal of Oceanology and Limnology 2022年第6期40卷 2081-2093页

作者： tian yan CAS Key Laboratory of Marine Ecology and Environmental Sciences Institute of OceanologyChinese Academy of SciencesQingdao 266071China Laboratory for Marine Ecology and Environmental Science Pilot National Laboratory for Marine Science and Technology(Qingdao)Qingdao 266237China Center for Ocean Mega-Science Chinese Academy of SciencesQingdao 266071China

The“harmful algae and algal toxins in coastal waters of China:investigation and database”project(HAATC)is funded(US$2.3 million)by the Ministry of Science and Technology of China for 60 months starting on the 1st Jan *** the 1990s,national projects and other related work have greatly improved harmful algal bloom(HAB)research in ***,the existing research on HABs is often limited to specific sea areas or specific algal bloom disasters,which is insufficient for understanding the long-term evolution of HAB occurrence under the influence of intensified human activity and global *** HAATC project intends to determine the overall distribution of marine harmful microalgae and macroalgae,and marine algal toxins(in phytoplankton and shellfish)through a large-scale investigation in the coastal waters of China and continuous investigation in key sea *** also aims to observe biotic and abiotic processes during harmful red tides and green tides,and establish an open database and query platform of HABs in *** research consortium,led by chief scientist *** yan,includes approximately 100 scientists and *** than 2 years of work have shown the increased distribution of HAB species(including cysts)and algal toxins in China’s coastal waters,the increased occurrence of macroalgae blooms(mainly by Ulva prolifera and Sargassum horneri)in the Southern Yellow Sea,increased amount of causative species being identified due to the use of molecular technologies in taxonomy,and new records of algal toxins such as azaspiracid,cycloimines and neurotoxinsβ-N-methylamino-l-alanine have been detected,which complicates the research in algal toxins and ***,the project will provide systematic basic data and techniques for the rapid and accurate identification of harmful algae species to support the research,monitoring,and control of harmful algal blooms,as well as seafood safety management in China.

关键词： harmful algae algal toxins coastal waters of China database

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Photochromic radical states in 3D covalent organic frameworks with zyg topology for enhanced photocatalysis

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National Science Review 2024年第7期11卷 177-188页

作者： tian-tian Ma Guo-Zhang Huang Xiao-Han Wang yan Liang run-Han Li Bin Wang Su-Juan Yao Jia-Peng Liao Shun-Li Li Yong yan Ya-Qian Lan School of Chemistry South China Normal University Department of Chemistry Guangdong Provincial Key Laboratory of Catalytic Chemistry Southern University of Science and Technology

Covalent-organic frameworks（COFs） with photoinduced donor-acceptor（D-A） radical pairs show enhanced photocatalytic activity in principle. However, achieving long-lived charge separation in COFs proves challenging due to the rapid charge recombination. Here, we develop a novel strategy by combining[6 + 4] nodes to construct zyg-type 3D COFs, first reported in COF chemistry. This structure type exhibits a fused Olympic-rings-like shape, which provides a platform for stabilizing the photoinduced D-A radical pairs. The zyg-type COFs containing catalytically active moieties such as triphenylamine and phenothiazine（PTZ） show superior photocatalytic production rates of hydrogen peroxide（H2O2）. Significantly, the photochromic radical states of these COFs show up to 400% enhancement in photocatalytic activity compared to the parent states, achieving a remarkable H2O2synthesis rate of 3324 μmol g-1h-1, which makes the PTZ-COF one of the best crystalline porous photocatalysts in H2O2production. This work will shed light on the synthesis of efficient 3D COF photocatalysts built on topologies that can facilitate photogenerating D-A radical pairs for enhanced photocatalysis.

关键词： 3D covalent-organic frameworks photochromic radical states donor and acceptor hydrogen peroxide photocatalysis

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a-Synuclein: A fusion chaperone significantly boosting the enzymaticperformance of PET hydrolase

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Chinese Journal of Chemical Engineering 2023年第12期64卷 18-25页

作者： Renwen tian yan Sun Department of Biochemical Engineering School of Chemical Engineering and Technology and Key Laboratory of Systems Bioengineering and Frontiers Science Center for Synthetic Biology(Ministry of Education)Tianjin UniversityTianjin 300350China

Extensive use of polyethylene terephthalate (PET) has brought about global environmental problems. Arecently reported PET hydrolase (PETase) discovered from Ideonella sakaiensis showed high potentialfor degrading PET at moderate temperatures, but its activity and stability need further improvementfor practical applications. Herein, we proposed to use a-synuclein (aS) as a fusion chaperone and createdsix PETase-aS fusion enzymes with linkers of different types and lengths. All the fusion enzymes exhibited improved enzymatic performance, presenting 1.5 to 2.6-fold higher activity towards bis-2(hydroxyethyl) terephthalate than PETase, as well as significantly increased stabilities. Fluorescencespectroscopy indicated that the chaperone fusion tightened the overall conformation and resulted inthe opening of the substrate binding pocket, which led to the improved thermal stability and catalyticactivity of the fusion enzymes. Remarkably, one of the fusion proteins, PETase-[(GS)(EK)]10-aS, showed3.2 to 5.1 times higher PET degradation capability than PETase. The significantly boosted PET degradationperformance was not only attributed to the enhanced enzymatic activity and stability, but also possiblydue to the binding affinity of the fused aS domain for PET. These findings demonstrated that aS was aneffective fusion chaperone for significantly enhancing the enzymatic performance of PETase.

关键词： PET hydrolase a-Synuclein Fusion enzyme Stability Pollution Degradation

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Numerical simulation for 2D double-diffusive convection(DDC) in rectangular enclosures based on a high resolution upwind compact streamfunction model Ⅰ: numerical method and code validation

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Applied Mathematics and Mechanics(English Edition) 2022年第9期43卷 1431-1448页

作者： Yaping yan Shuang WU Kaiyuan tian Zhenfu tian Institute of Mechanics and Computational Engineering Department of Aeronautics and AstronauticsFudan UniversityShanghai 200433China College of Science Liaoning Technical UniversityFuxin 123000Liaoning ProvinceChina Research Institute of Intelligent Complex Systems Fudan UniversityShanghai 200433China School of Life Sciences Fudan UniversityShanghai 200433China

A high resolution upwind compact streamfunction numerical algorithm for two-dimensional(2D)double-diffusive convection(DDC)is *** unsteady Navier-Stokes(N-S)equations in the streamfunction-velocity form and the scalar temperature and concentration equations are *** optimized third-order upwind compact(UCD3 opt)scheme with a low dispersion error for the first derivatives is utilized to approximate the third derivatives of the streamfunction in the advection terms of the N-S equations and the first derivatives in the advection terms of the scalar temperature and concentration *** remaining first derivatives of the streamfunction(velocity),temperature,and concentration variables used in the governing equations are discretized by the fourth-order compact Pade(SCD4)*** the temperature and concentration variables and their approximate values of the first derivatives obtained by the SCD4 schemes,the explicit fourth-order compact schemes are suggested to approximate the second derivatives of temperature and concentration in the diffusion terms of the energy and concentration *** discretization of the temporal term is executed with the second-order Crank-Nicolson(C-N)*** assess the spatial behavior capability of the established numerical algorithm and verify the developed computer code,the DDC flow is numerically *** obtained results agree well with the benchmark solutions and some accurate results available in the literature,verifying the accuracy,effectiveness,and robustness of the provided ***,a preliminary application of the proposed method to the DDC is carried out.

关键词： double diffusive convection(DDC) high resolution heat and mass transfer upwind compact difference streamfunction formulation

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The focal depths of the 2008 Panzhihua earthquake sequence and the stress field in the source region

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Science China Earth Sciences 2020年第3期63卷 439-451页

作者： yan LUO Li ZHAO Jianhui tian Key Laboratory of Earthquake Prediction Institute of Earthquake ForecastingCEABeijing 100036China School of Earth and Space Sciences Peking UniversityBeijing 100871China

Focal depths of the 2008 Ms6.1 Panzhihua earthquake sequence and tectonic stress field in the source area are *** depths of 24 earthquakes in Panzhihua earthquake sequence with a magnitude M≥3.0 were determined using the seismic depth phase sPL;additionally,the focal depths of 232 earthquakes were measured by fitting the threecomponent waveforms of the P and S *** source depth of the main shock is^12 *** majority of the aftershocks with magnitude M≥3.0 occurred in the brittle upper crust at the depths range of 12-18 ***,the Source mechanisms of the 232events around the Panzhihua earthquake source area were determined,and the results show that the earthquakes have predominantly strike-slip mechanisms in the Dianzhong Block,but display complexity of the focal mechanisms outside and near the boundary of the Dianzhong *** 232 earthquake mechanisms from this study are combined with the solutions from the Global Centroid Moment Tensor (GCMT) catalog to derive 2D stress *** inversion results show that the Dianzhong block is predominantly under a strike slip faulting regime and the direction of the maximum principal compressionσ1 is northwestsoutheast (NW-SE)-*** distribution is coincide with GPS velocity ***,orientations of principal stress axes as well as the faulting types change outside and near the Dianzhong *** results show that the tectonic stress field in the study area is predominantly controlled by the southeast (SE)-trending horizontal movement and clockwise rotation of the Dianzhong block as a result of the eastward movement of eastern Tibetan meeting the old and rigid South China block (SCB).The Panzhihua earthquake ruptured at^12 km depth where the tectonic stress regime is under the SE-direction horizontal compression and the NE-direction horizontal extension.

关键词： Panzhihua earthquake sequence Depth phase Focal mechanism solution Tectonic stress field

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