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Chinese Chemical Letters 2024年第5期35卷 135-140页

作者： Zhen liu Zhi-Yuan Ren Chen Yang Xiangyi Shao li Chen xin li State Key Laboratory of Elemento-Organic Chemistry Frontiers Science Center for New Organic MatterCollege of ChemistryNankai UniversityTianjin 300071China Haihe Laboratory of Sustainable Chemical Transformations Tianjin 300192China Zhenhai High School of Zhejiang Ningbo 315299China

Catalytic enantioselective alkenylation is an efficient method to construct chiral alkene molecules,but the asymmetric alkenylation of simple alkenes catalyzed by metal-free catalysts remains an elusive ***,we reported an asymmetric alkenylation of benzoxazinones with diarylethylenes by utilizing a B(C_(6)F_(5))_(3)/chiral phosphoric acid catalyst.A broad of benzoxazinones and diarylethylenes with electron-withdrawing and electron-donating groups were tolerated(up to 95%yield and 97.5:2.5 e.r.)in the methodology under mild reaction ***,the synthetic utility was confirmed by the scaled-up reaction and transformations of the *** mechanism was preliminarily explored by control reactions,nonlinear effect experiment and DFT calculations.

关键词： Asymmetric alkenylation Simple alkenes Benzoxazinones B(C_(6)F_(5))_(3)/chiral phosphoric acid Theoretical calculations

Efficient capture of difluorocarbene by pyridinium 1,4-zwitterionic thiolates:A concise synthesis of difluoromethylene-containing 1,4-thiazine derivatives

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Chinese Chemical Letters 2024年第4期35卷 367-370页

作者： Zhiwei Chen Heyun Sheng Xue li Menghan Chen xin li Qiuling Song Institute of Next Generation Matter Transformation College of Materials Science&Engineering and College of Chemical Engineering at Huaqiao UniversityXiamen 361021China Fujian University Key Laboratory of Molecule Synthesis and Function Discovery College of ChemistryFuzhou UniversityFuzhou 350108China State Key Laboratory of Organometallic Chemistry and Key Laboratory of Organofluorine Chemistry Shanghai Institute of Organic ChemistryChinese Academy of SciencesShanghai 200032China

A practical method for the construction of difluoromethylene-containing 1,4-thiazine moieties using readily available diethyl bromodifluoromethanephosphonate(BrCF_(2)PO(OEt)_(2))as difluorocarbene precusor has been *** transformation features the efficient capture of difluorocarbene by pyridinium 1,4-zwitterionic thiolates.A series of structurally novel and functionalized difluoromethylene-containing 1,4-thiazine derivatives were thus synthesized in good yields.

关键词： Difluoromethylene Pyridinium 1 4-zwitterionic thiolates 1 4-Thiazine derivatives

Controllable Ring-opening Polymerization ofδ-Valerolactone Catalyzed by Quinolinyl-Urea/MTBD Systems

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Chinese Journal of Polymer Science 2024年第8期42卷 1103-1110页

作者： xin-Yu liu liang Zhu Su-Yun Jie Bo-Geng li State Key Laboratory of Chemical Engineering College of Chemical and Biological EngineeringZhejiang UniversityHangzhou 310058China

Due to their excellent biocompatibility and biodegradability,aliphatic polyesters are widely used in the biomedical,packaging and agricultural fields,which are usually accessed by the ring-opening polymerization(ROP)of lactones and the catalysts particularly play an important *** a series of quinolinyl-urea catalysts have been synthesized via the reaction between isocyanate and aminoquinoline with an amino group at different substitution positions and *** combination with 7-methyl-1,5,7-triazabicyclo[4,4,0]dec-5-ene(MTBD)as a cocatalyst and benzyl alcohol(BnOH)as an initiator,1-(3,5-bis(trifluoromethyl)phenyl)-3-(quinolin-3-yl)urea(3-QU)was observed to be most active for the ROP ofδ-valerolactone(δ-VL).The polymerization conditions were optimized by varying the type of organic base,catalyst concentration and reaction *** changing the ratio of[M]_0/[I],linear polyvalerolactones(PVLs)with different molecular weights and narrow molecular weight distribution were *** kinetic and chain extension experiments were carried out to prove the"living"/controllable *** the NMR experiments were used to support the proposal of possible mechanism.

关键词： Quinolinyl-urea Ring-opening polymerization PVL

CO_(2) corrosion of X80 steel welded joints under micro-turbulence induced by welding reinforcement height

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Journal of Iron and Steel Research International 2024年第4期31卷 1015-1032页

作者： Xiao-hui Dou Bin li Zong-hao He xin-wei Zhang Da-lei Zhang Yan li School of Materials Science and Engineering China University of Petroleum(East China)Qingdao 266580ShandongChina School of Energy and Power Engineering Jiangsu UniversityZhenjiang 212013JiangsuChina

Corrosion failure accidents owing to flow erosion and pipeline corrosion frequently occur during *** welding reinforcement height(WRH)can induce locally micro-turbulent flow field,which aggravates local corrosion of welded joints.A high wall shear stress(WsS)experimental setup was established to conduct the online electrochemical corrosion *** influence of WRH sizes on local corrosion of welded joints was studied at different flow *** electrochemical signals of the local corrosion of X80 welded joints at different flow rates were monitored in real time using electrochemical impedance spectroscopy and wire beam *** addition,the corrosion products composition and properties were *** results show that the micro-turbulent flow fields induced by the WRHs can enhance ion mass transfer near the welded *** corrosion products on the WRH surface also present different microscopic morphologies at different flow *** strong flow fields,the locally enhanced wsS can peel off the dense corrosion product partially,leading to the electrochemical distribution of large cathode and small anode,which accelerates the occurrence and development processes of the local corrosion of welded *** scientific guidelines for the corrosion protection of long-distance oil and gas pipelines can be potentially provided.

关键词： X80 steel welded joint Welding reinforcement height Micro-turbulence CO_(2)corrosion-Ion mass transfer

Corneal nerve changes by anti-glaucoma medications examined by in vivo confocal microscopy

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International Journal of Ophthalmology(English edition) 2024年第9期17卷 1645-1653页

作者： xin-Yuan Zhu Qing-shu Ge Zong-Yi li Long-Fang Zhou Qian-Wen Bu Ying Su xin-Jie Wang Qing-Jun Zhou Xiao-Jing Pan Die Hu School of Clinical Medicine Shandong Second Medical UniversityWeifang 261053Shandong ProvinceChina Eye Institute of Shandong First Medical University Qingdao Eye Hospital of Shandong First Medical UniversityQingdao 266071Shandong ProvinceChina State Key Laboratory Cultivation Base Shandong Provincial Key Laboratory of OphthalmologyQingdao 266071Shandong ProvinceChina School of Ophthalmology Shandong First Medical UniversityQingdao 266071Shandong ProvinceChina

AIM:To evaluate the effects of antiglaucoma eye drops on corneal nerves by in vivo confocal microscopy(IVCM).METHODS:This study comprised 79 patients diagnosed with glaucoma and 16 healthy control *** the glaucoma patients,54 were treated with medication,while 25 remained *** corneal images were evaluated by IVCM,and then ACCMetrics was used to calculate the following parameters:corneal nerve fiber density(CNFD),branch density(CNBD),fiber length(CNFL),total branch density(CTBD),fiber area(CNFA),fiber width(CNFW),and fractal dimension(CNFrD).The correlation between IVCM parameters and drugs was evaluated using non-parametric measurements of Spearman’s rank correlation ***:The CNFD was reduced in glaucoma groups compared to healthy subjects(Pline,while CNFW increased(all P<0.01).For the brinzolamide-therapy group,there was a significant decrease in CNFD and CNFL compared to the other monotherapy groups(P<0.001).In the absence of medication,CNFD in males was lower than that in females(P<0.05).Among patients under medication therapy,CNFD remained consistent between males and ***:Antiglaucoma eye drops affect the microstructure of corneal *** and ACCMetrics are useful tools that could be used to evaluate the corneal nerve changes.

关键词： glaucoma therapy corneal nerve fibers in vivo confocal microscopy ACCMetrics

Orbital pacing and secular evolution of lake-level changes reconstructed by sedimentary noise modeling during the Early Jurassic icehouses-(super)greenhouses

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Science China Earth Sciences 2024年第1期67卷 252-267页

作者： Meng li xin li Stephen P.HESSELBO Mingjie li Wenjin liU Wei WU Jienan PAN Ruizhen GAO School of Resources and Environment Henan Polytechnic UniversityJiaozuo 454000China Camborne School of Mines and Environment and Sustainability Institute University of ExeterPenryn TR109FEUnited Kingdom Qinghai No.105 Coal Geological Exploration Team Xining 810000China

Lake-level changes can significantly affect paleoenvironmental evolution,resource occurrence,terrestrial carbon budget,and biodiversity in continental *** is one of the most critical factors controlling lake-level *** of the Early Jurassic has been evidenced by oscillating icehouses to(super)greenhouses with interrupted intermittent extreme climatic events(hyperthermal and cooling),e.g.,the Toarcian oceanic anoxic event(~183 Ma)and the late Pliensbachian cooling event(~185 Ma).Lake-level evolution and hydrologic cycling on Earth’s surface during the Early Jurassic icehouses-to-(super)greenhouses are thus far poorly understood due to a lack of continuous high-resolution nonmarine *** we present a super-long nonmarine lake level record for this pivotal interval from the early Pliensbachian to Toarcian by sedimentary noise modeling,and construct a 16.7-Myr-long astronomical time scale(174.2 Ma to 190.9 Ma)based on cyclostratigraphy analysis of rock color datasets(CIE b*)of the Qaidam *** results document lake-level oscillations on a 5-to 10-million-year(Myr)scale which shows a pronounced correlation with long-term climate variation and extreme climatic events,and 1-to 2.5-Myr-scale lake-level changes that are prominently paced by the 2.4-Myr long-eccentricity forcing and the 1.2-Myr obliquity *** the Pliensbachian Stage,the 1.2-Myr-scale lake-level changes are in phase with the coeval sealevel *** forced growth and decay of the ephemeral or permanent ice sheets in polar regions are interpreted to control the synchronous ups-and-downs of continental lake level and global sea ***,during the Toarcian ice-free greenhouses to(super)greenhouses,the 1.2-Myr-scale lake-level variations show an anti-phase relationship with global sea level,indicating a‘seesaw’interaction between continental reservoirs(lakes and groundwater)and global *** 2.4-Myr longeccentricity cycles mainly regulate variation

关键词： Milankovitch cycles Orbital forcing Sedimentary noise model Lake level Continental basins

Improving the value of molecular testing:current status and opportunities in colorectal cancer precision medicine

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Cancer Biology & Medicine 2024年第1期21卷 21-28页

作者： Haiyun li linwei Guo Chenchen Wang xin Hu Ye Xu Department of Colorectal Surgery Fudan University Shanghai Cancer CenterShanghai 200032China Department of Oncology Shanghai Medical CollegeFudan UniversityShanghai 200032China Department of Gastrointestinal Medical Oncology Fudan University Shanghai Cancer CenterShanghai 200032China Precision Cancer Medical Center Affiliated with Fudan University Shanghai Cancer Center Shanghai 201315China

Colorectal cancer(CRC)is the second leading cause of cancer-related deaths *** radical resection with adjuvant chemotherapy remains the primary treatment choice for CRC,but the 5-year postoperative survival rate is only approximately 60%,and approximately one-third of patients with CRC experience recurrence within 2 years of ***,the transformation of high-throughput sequencing has accelerated the development of precision *** example,KRAS mutations indicate resistance to anti-epidermal growth factor receptor(EGFR)-targeted therapies in ***,molecular-guided individualized therapy has brought new promise in major clinical areas and challenges,such as novel biomarkers predicting sensitivity and resistance to immunotherapy for microsatellite stable(MSS)CRC.

关键词： cancer chemotherapy colorectal

Drinking water quality & health risk assessment of secondary water supply systems in residential neighborhoods

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Frontiers of Environmental Science & Engineering 2024年第2期18卷 47-62页

作者： Yating Wei Dong Hu Chengsong Ye Heng Zhang Haoran li xin Yu College of the Environment&Ecology Xiamen UniversityXiamen 361102China School of Public Health Shandong First Medical University&Shandong Academy of Medical SciencesJinan 250117China

Secondary water supply systems(SWSSs)are important components of the water supply infrastructure that ensure residents’drinking water *** are characterized by long detention time,warm temperature,and unreasonable management,which may trigger the deterioration of water quality and increase *** this study,drinking water quality index(DWQI)and health risk assessment(HRA)were selected and modified to quantitatively assess the water quality and health risks of SWSSs in residential *** total,121 seasonal water samples were *** was observed that the water quality was excellent with the DWQI of 0.14±0.04,excluding one sample,which was extremely poor owing to its excessive total bacterial *** HRA results revealed that the health risks were low:negligible non-carcinogenic risk for any population;negligible and acceptable carcinogenic risk for children aged 6–17 and ***,samples revealed higher carcinogenic risk(7.63×10−5±3.29×10−6)for children aged 0–5,and arsenic was the major *** samples had poor water quality and higher health risks,which called for *** further investigate the water quality and health risks of SWSSs,monthly sampling was conducted during *** 24 water samples were qualified in Chinese standard(GB 5749-2022)and characterized as excellent *** HRA results were consistent with the seasonal samples’and the health risks were mainly concentrated in ***,our study provides a suitable framework for water quality security,advice for managers,and references for administrators in other cities.

关键词： Drinking water quality Water quality index Health risk assessment Secondary water supply systems Heavy metals

Large eddy simulation of boundary layer combustion of hydrogen and hydrocarbon fuel films in a modeled scramjet combustor

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Chinese Journal of Aeronautics 2024年第7期37卷 109-133页

作者： Jianfei WEI Silong ZHANG Jingying ZUO xin li Jiang QIN Wen BAO School of Energy Science and Engineering Harbin Institute of TechnologyHarbin 150001China

Supersonic fuel film cooling is a promising way to simultaneously reduce the severe wall heat and friction load of the internal passage in a scramjet engine when operating at hypersonic *** eddy simulations were performed to investigate the cooling and wall friction characteristics of hydrogen and hydrocarbon films under inert and reactive *** results show that the essential difference of the turbulent state in the mixing layer contributes to the totally different behaviors of the cooling and wall friction reduction performances of the two fuel *** turbulent transport processes between the hydrogen film and the mainstream are much weaker as compared to the case of hydrocarbon film,making inert hydrogen rather superior in cooling and friction reduction ***,the increase of wall temperature for hydrogen film under the inert case is mainly driven by the loss of hydrogen with high heat capacity instead of by direct heat ***,the film cooling performance severely deteriorates when the hydrogen film burns due to presence of severe heat release sources near the *** the other hand,combustion of hydrocarbon film in the boundary layer can remarkably improve its originally barely-satisfactory cooling and friction reduction performance to the level comparable to that of hydrogen film,due to the suppression of turbulent transport processes in the mixing layer and presence of heat absorption sources near the ***,the hydrogen film is more advantageous in friction reduction,while the hydrocarbon film is more suitable for cooling.

关键词： Supersonic film cooling Hydrogen Hydrocarbon Boundary layer combustion Large eddy simulation

Construction of multifunctional lanthanum manganese mixed nanoparticles mediated by ionic liquids for selective aerobic oxidation of cyclohexane

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Rare Metals 2024年第5期43卷 2205-2221页

作者： Hao li Rui-Rui Zhang Ke-xin li shuang Wei Yu-Mei liu Rui-Xia liu Beijing Key Laboratory of Ionic liquids Clean Process CAS Key Laboratory of Green Process and EngineeringState Key Laboratory of Multiphase Complex SystemsInstitute of Process EngineeringChinese Academy of SciencesBeijing 100190China University of Chinese Academy of Sciences Beijing 100049China

Selective oxidation of alkanes to produce highvalue chemicals is an essential strategy and means to realize efficient utilization of *** this work,a strategy of lanthanum manganese mixed metal oxides(LMMO)regulated via a facile ionic liquid(IL)-assisted hydrothermal method was proposed to construct the multifunctional catalysts,which exhibited excellent catalytic performance in the selective aerobic oxidation of *** 8.9%cyclohexane conversion with 90%KA oi(cyclohexanol and cyclohexanone)selectivity was achieved over the optimal LMMO catalyst under mild *** effects of anion type,carbon chain length and concentration of ILs on the structure and properties of catalysts were investigated through various characterizations,indicating the structure-directing and template effect of ILs on the multifunctional *** formation of self-assembled spherical nanoparticles followed the"dissolution-nucleation-proliferation"mechanism with the introduction of 1-butyl-3-methylimidazolium hydrogen sulfate,ascribing the synergistic effect between the microenvironment of ILs and the hydrothermal ***,the high reactive oxygen concentration redox capacity,and suitable basic sites of LMMO catalysts mediated by ILs enhance the activation of C-H bonds and molecular oxygen,simultaneously influencing the adsorption and desorption of the substrate.A comprehensive understanding of the high KA oil selectivity and radical reaction mechanism was elucidated based on in situ diffuse reflectance infrared Fourier transform spectroscopy(DRIFTS)and radical trapping *** recycling and regeneration experiments further illuminated that the removal of adsorbed cyclohexanone acting on the LMMO catalyst was the key to achieve high KA oil selectivity.

关键词： Ionic liquids Nanoparticle Multifunctional catalyst Cyclohexane oxidation