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Chinese Journal of Chemistry 2024年第14期42卷 1637-1643页

作者： Jie ma Xufeng li Yuqing chen Yongjia Shi Xiuyan Song Jian Lv Daoshan Yang Key Laboratory of Optic-electric Sensing and Analytical Chemistry for life Science MOECollege of Chemistry and Molecular EngineeringQingdao University of Science and TechnologyQingdaoShandong266042 China Zhejiang Wansheng Co. Ltd.LinhaiZhejiang317000 China National Engineering Research Center of Low-Carbon Processing and Utilization of Forest Biomass Nanjing Forestry UniversityNanjingJiangsu210037 China

Although,great achievements have been made in the synthesis of heterocycles using radical addition/cyclization strategy,developing versatile alkyl radical precursors,especially the non-stabilized long chain alkyl radicals for this strategy still remains a huge ***,we report an efficient annulation cascade reaction between cyclosulfonium salts and alkenes for the synthesis of sulfur-containing N-heterocycles by visible light/copper catalysis under mild *** C—S bond cleavage/radical cascade reaction delivers a variety of corresponding N-heterocycles containing aryl alkyl thioether motifs with good functional group ***,the current system could be used for the late-stage functionalization of complex bioactive molecules.

关键词： Visible light Radical reactions C-C coupling Sulfur heterocycles Photoredox catalysis

Multiple pollutants from crop and livestock production in the Yangtze River: status and challenges

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Frontiers of Agricultural Science and Engineering 2024年第1期11卷 134-139,I0005页

作者： lihua ma Shiyang li linfa FANG Xuanjing chen Ran XIAO Xiaoxuan SU Zhaolei li Zhaohai BAI lin ma Prakash LAKSHmaNAN Xinping chen Interdisciplinary Research Center for Agriculture Green development in Yangtze River Basin College of Resources and EnvironmentSouthwest UniversityChongqing 400715China Water Systems and Global Change Group Wageningen University&Research6708 PB Wageningenthe Netherlands Key Laboratory of Agricultural Water Resources Center for Agricultural Resources ResearchInstitute of Genetic and Developmental BiologyChinese Academy of SciencesShijiazhuang 050021China Key Laboratory of Sugarcane Biotechnology and Genetic Improvement(Guangxi) Ministry of Agriculture and Rural AffairsGuangxi Key Laboratory of Sugarcane Genetic ImprovementSugarcane Research InstituteGuangxi Academy of Agricultural SciencesNanning 530007China Queensland Alliance for Agriculture and Food Innovation University of QueenslandSt Lucia 4067Australia

The rapid increase in the proportion of cash crops and livestock production in the Yangtze River Basin has led to commensurate increases in fertilizer and pesticide inputs. Excessive application of chemical fertilizer, organophosphorus pesticides and inappropriate disposal of agricultural waste induced water pollution and potentially threaten Agriculture Green development(AGD). To ensure food security and the food supply capacity of the Yangtze River Basin, it is important to balance green and development, while ensuring the quality of water bodies. Multiple pollutants affect the transfer, adsorption, photolysis and degradation of each other throughout the soil-plant-water system. This paper considers the impact of multi-pollutants on the nitrogen and phosphorus cycles especially for crops, which are related to achieving food security and AGD. It presents prospective on theory, modeling and multi-pollutant control in the Yangtze River Basin for AGD that are of potential value for other developing regions.

关键词： Agriculture Green development crop production livestock production multi-pollutant models multiple pollutants Yangtze River Basin

Revealing precipitation behavior and mechanical response of wire-arc directed energy deposited Mg-Gd-Y-Zr alloy by tailoring aging procedures

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International Journal of Extreme manufacturing 2024年第4期6卷 176-200页

作者： Xinzhi li Xuewei Fang Zhiyan Zhang Shahid Ghafoor Ruikai chen Yi liu Kexin Tang Kai li Minghua ma Jiahao Shang Ke Huang State Key Laboratory for manufacturing Systems Engineering School of Mechanical EngineeringXi'an Jiaotong UniversityXi'an 710049 ShaanxiPeople's Republic of China

Mg-Gd-Y-Zr alloy,as a typical magnesium rare-earth(Mg-RE)alloy,is gaining popularity in the advanced equipment manufacturing fields owing to its noticeable age-hardening properties and high specific ***,it is extremely challenging to prepare wrought components with large dimensions and complex shapes because of the poor room-temperature processability of Mg-Gd-Y-Zr ***,we report a wire-arc directed energy deposited(deD)Mg-10.45Gd-2.27Y-0.52Zr(wt.%,GW102K)alloy with high RE content presenting a prominent combination of strength and ductility,realized by tailored nanoprecipitates through an optimized heat treatment ***,the solution-treated sample exhibits excellent ductility with an elongation(EL)of(14.6±0.1)%,while the aging-treated sample at 200°C for 58 h achieves an ultra-high ultimate tensile strength(UTS)of(371±1.5)***,the aging-treated sample at 250°C for 16 h attains a good strength-ductility synergy with a UTS of(316±2.1)MPa and a EL of(8.5±0.1)%.Particularly,the evolution mechanisms of precipitation response induced by various aging parameters and deformation behavior caused by nanoprecipitates type were also systematically *** excellent ductility resulted from coordinating localized strains facilitated by active slip *** the ultra-high strength should be ascribed to the dense nano-β'hampering dislocation ***,the shearable nano-β1 contributed to the good strength-ductility *** work thus offers insightful understanding into the nanoprecipitates manipulation and performance tailoring for the wire-arc deD preparation of large-sized Mg-Gd-Y-Zr components with complex geometries.

关键词： wire-arc directed energy deposition Mg-Gd-Y-Zr alloy precipitation response prominent strength-ductilitycombination deformation mechanism

Three Types of Isocoumarins with Unusual Carbon Skeletons from Artemisia dubia var. subdigitata and Their Antihepatoma Activity

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Chinese Journal of Chemistry 2024年第16期42卷 1901-1912页

作者： Ke-Xin Yang Tian-Ze li Yun-Bao ma Yong-Cui Wang Feng-Jiao li Ji-Jun chen State Key Laboratory of Phytochemistry and Plant Resources in West China Kunming Institute of BotanyChinese Academy of SciencesKunmingYunnan 650201China University of Chinese Academy of Sciences Beijing 100049China

Ten novel isocoumarins,including four pairs of enantiomers,were isolated from Artemisia dubia ***(Asteraceae).Compounds 1,2 and 3a/3b possessed a unique 6/6/6-tricyclic system comprising an unusual 1-(2-methylcyclohexyl)propan-1-one moiety fused with isocoumarin core *** 4a/4b were characterized as an unexpected 2,5-dimethylcyclohexan-1-one scaffold,and compounds 5a/5b and 6a/6b were rare 1,*** structures and absolute configurations were elucidated through spectroscopic data,X-ray crystallography,ECD and NMR calculations with DP4+*** biosynthetic pathways were proposed from the naturally occurring *** pharmacological analysis suggested that the targets of compound 1 were significantly enriched in the cell cycle and Pl3K-Akt signaling *** molecular docking revealed that compound 1 had high binding affinity with CDK2(total score:6.8717).Furthermore,compounds 1 and 2 exhibited inhibitory activity on three human hepatoma cell lines,with inhibitory ratios of 85.1% and 84.5%(HepG2),88.2% and 87.3%(Huh7),and 69.2% and 69.1%(SK-Hep-1)at 200μmol·L^(-1),respectively.

关键词： Artemisia dubia var.subdigitata Isocoumarins Antihepatoma activity Cancer Natural products X-ray diffraction

matrix-Mediated Color-Tunable Ultralong Organic Room Temperature Phosphorescence of 7H-Benzo[c]carbazole derivatives

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CCS Chemistry 2024年第3期6卷 798-811页

作者： chen Qian Xue Zhang Zhimin ma Xiaohua Fu Zewei li Huiwen Jin Mingxing chen Hong Jiang Zhiyong ma Beijing Advanced Innovation Center for Soft matter Science and Engineering State Key Laboratory of Organic–Inorganic CompositesCollege of Chemical EngineeringBeijing University of Chemical TechnologyBeijing 100029 Beijing National Laboratory for Molecular Sciences College of Chemistry and Molecular EngineeringPeking UniversityBeijing 100871

Building on the recent systematic research on 1Hbenzo[f]indole(Bd),an important advancement in constructing ultralong organic room temperature(UORTP)materials with a universal strategy via a readily obtained unit(7H-Benzo[c]carbazole,BCz)is proposed in this *** powders of BCz and its derivatives merely exhibit blue fluorescence at ambient ***,when BCz and its derivatives are dispersed into polymer or powder matrixes,strong photo-activated green UORTP can be observed from their doped systems at room ***,the UORTP color can be tuned between green and yellow depending on the *** ultralong phosphorescence originates from the generation of charge-separated states via *** matrixes play a key role in both stabilizing charge-separated states and controlling UORTP *** interestingly,when using polymethyl methacrylate as matrix,the doped films achieve stronger photo-activated ultralong phosphorescence underwater than in air at room *** Bd,BCz achieves better performance not only in ultralong phosphorescence properties but also in practical *** work gains a deeper insight into the mechanism of UORTP and paves a new approach to applying organic phosphorescent materials to underwater coating and imaging.

关键词： 7H-Benzo[c]carbazole ultralong organic room temperature phosphorescence ion radical matrix-mediated color tunning underwater application

Fe-N_(x) sites coupled with core-shell FeS@C nanoparticles to boost the oxygen catalysis for rechargeable Zn-air batteries

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Journal of Energy Chemistry 2024年第3期90卷 565-577,I0013页

作者： Katam Srinivas Zhuo chen Anran chen Fei ma Ming-qiang Zhu Yuanfu chen School of Integrated Circuit Science and Engineering and State Key Laboratory of Electronic Thin Films and Integrated DevicesUniversity of Electronic Science and Technology of ChinaChengdu 610054SichuanChina College of Mechanical and Electronic Engineering Northwest A&F UniversityYangling 712100ShaanxiChina School of materials and Energy Yunnan UniversityKunming 650091YunnanChina

The development of efficient single-atom catalysts(SACs) for the oxygen reduction reaction(ORR)remains a formidable challenge,primarily due to the symmetric charge distribution of metal singleatom sites(M-N_(4)).To address such issue,herein,Fe-N_(x) sites coupled synergistic catalysts fabrication strategy is presented to break the uniform electronic distribution,thus enhancing the intrinsic catalytic ***,atomically dispersed Fe-N_(x) sites supported on N/S-doped mesoporous carbon(NSC)coupled with FeS@C core-shell nanoparticles(FAS-NSC@950) is synthesized by a facile hydrothermal reaction and subsequent *** to the presence of an in situ-grown conductive graphitic layer(shell),the FeS nanoparticles(core) effectively adjust the electronic structure of single-atom Fe sites and facilitate the ORR kinetics via short/long-range coupling ***,FAS-NSC@950displays a more positive half-wave potential(E_(1/2)) of 0.871 V with a significantly boosted ORR kinetics(Tafel slope=52.2 mV dec^(-1)),outpacing the commercial Pt/C(E_(1/2)=0.84 V and Tafel slope=54.6 mV dec^(-1)).As a bifunctional electrocatalyst,it displays a smaller bifunctional activity parameter(ΔE) of 0.673 V,surpassing the Pt/C-RuO_(2) combination(ΔE=0.724 V).Besides,the FAS-NSC@950-based zincair battery(ZAB) displays superior power density,specific capacity,and long-term cycling performance to the Pt/C-Ir/C-based *** work significantly contributes to the field by offering a promising strategy to enhance the catalytic activity of SACs for ORR,with potential implications for energy conversion and storage technologies.

关键词： Fe-N_(x)sites Core-shell FeS@C Synergistic interactions Oxygen reduction reaction Zn-air battery

Simulation study on cuttings transport of the backreaming operation for long horizontal section wells

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Petroleum Science 2024年第2期21卷 1149-1170页

作者： Yu-Fei chen Hui Zhang Wen-Xin Wu Jun li Yong Ouyang Zong-Yu Lu de-Xin ma Yong-Chuan Wu Jun-Bo liu Ke-Rou liu Zhuo-Xin Dong China University of Petroleum(Beijing) Beijing102249China Beijing Normal University at Zhuhai Experimental and Practical Education Innovation CenterZhuhai519087GuangdongChina Oil&Gas Technology Research Institute of PetroChina Changqing Oilfield Company Xi'an710016ShaanxiChina PetroChina Xinjiang Oilfield Company Karamay834002XinjiangChina China Oilfield Services Ltd. Tianjin300459China

The backreaming operation plays a significant role in safe drilling for horizontal wellbores, while it may cause severe stuck pipe accidents. To lower the risk of the stuck pipe in backreaming operations, the mechanism of cuttings transport needs to be carefully investigated. In this research, a transient cuttings transport with multiple flow patterns model is developed to predict the evolution of cuttings transported in the annulus while backreaming. The established model can provide predictions of the distribution of cuttings bed along the wellbore considering the bulldozer effect caused by large-size drilling tools(LSDTs). The sensitivity analyses of the size of LSDTs, and backreaming operating parameters are conducted in Section 4. And a new theory is proposed to explain the mechanism of cuttings transport in the backreaming operation, in which both the bit and LSDTs have the “cleaning effect” and “plugging effect”.The results demonstrate that the cuttings bed in annuli is in a state of dynamic equilibrium, but the overall trend and the distribution pattern are obvious. First, larger diameters and longer drilling tools could lead to a higher risk of the stuck pipe. Second, we find that it is not the case that the higher flow rate is always better for hole cleaning, so three flow-rate intervals are discussed separately under the given conditions. When the “dangerous flow rate”(maller flow rate instead facilitates borehole cleaning. If the flow rate is large enough to be in the “high flow rate” interval(>35 L/s in Case 4),the higher the flow rate, the better the cleaning effect of cuttings beds. Third, an interval of tripping velocity called “dangerous velocity” is proposed, in which the cuttings bed accumulation near the LSDTs is more serious than

关键词： Backreaming Stuck pipe Hole cleaning Transient solid transport Multiple flow patterns

Revealing Tissue Heterogeneity and Spatial Dark Genes from Spatially Resolved Transcriptomics by Multiview Graph Networks

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Research 2024年第2期6卷 629-645页

作者： Ying li Yuejing Lu chen Kang Peiluan li Luonan chen School of mathematics and Statistics Henan University of Science and TechnologyLuoyang471023China Longmen Laboratory LuoyangHenan471003China Key Laboratory of Systems Biology Institute of Biochemistry and Cell BiologyCenter for Excellence in Molecular Cell ScienceChinese Academy of SciencesShanghai201100China Key Laboratory of Systems Health Science of Zhejang Province Hangzhou Institute for Advanced StudyUniversity of Chinese Academy of SciencesHangzhou310000China School of life Science and Technology ShanghaiTech UniversityShanghai201100.China

Spatially resolved transcriptomics(SRT)is capable of comprehensively characterizing gene expression patterns and providing an unbiased image of spatial *** fully understand the organizational complexity and tumor immune escape mechanism,we propose stMGATF,a multiview graph attention fusion model that integrates gene expression,histological images,spatial location,and gene *** better extract information,stMGATF exploits SimCLRv2 for visual feature exaction and employs edge feature enhanced graph attention networks for the learning potential embedding of each view.A global attention mechanism is used to adaptively integrate 3 views to obtain low-dimensional *** to diverse SRT datasets,stMGATF is robust and outperforms other methods in detecting spatial domains and denoising data even with different resolutions and *** particular,stMGATF contributes to the elucidation of tissue heterogeneity and extraction of 3-dimensional expression ***,considering the associations between genes in tumors,stMGATF can identify the spatial dark genes ignored by traditional methods,which can be used to predict tumor-driving transcription factors and reveal tumor immune escape mechanisms,providing theoretical evidence for the development of new immunotherapeutic strategies.

关键词： Spatial integrate driving

Sequestration of helium and xenon via iron-halide compounds in early Earth

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matter and Radiation at Extremes 2024年第3期9卷 83-88页

作者： Jurong Zhang Hanyu liu Changfeng chen Yanming ma Key Laboratory of material Simulation Methods and Software of Ministry of Education and State Key Laboratory of Superhard materials College of PhysicsJilin UniversityChangchun 130012China School of Physics and Electronics Shandong Normal UniversityJinan 250014China International Center of Future Science Jilin UniversityChangchun 130012China department of Physics and Astronomy University of NevadaLas VegasNevada 89154USA

The terrestrial abundance anomalies of helium and xenon suggest the presence of deep-Earth reservoirs of these elements,which has led to great interest in searching for materials that can host these usually unreactive ***,using an advanced crystal structure search approach in conjunction with first-principles calculations,we show that several Xe/He-bearing iron halides are thermodynamically stable in a broad region of P–T phase space below 60 *** results present a compelling case for sequestration of He and Xe in the early Earth and may suggest their much wider distribution in the present Earth than previously *** findings offer insights into key material-based and physical mechanisms for elucidating major geological phenomena.

关键词： halide searching insight

Branch-Chain-Rich Diisopropyl Ether with Steric Hindrance Facilitates Stable Cycling of lithium Batteries at-20℃

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Nano-Micro Letters 2024年第10期16卷 121-135页

作者： Houzhen li Yongchao Kang Wangran Wei Chuncheng Yan Xinrui ma Hao chen Yuanhua Sang Hong liu Shuhua Wang State Key Laboratory of Crystal materials Shandong UniversityJinan 250100People's Republic of China

li metal batteries(LMBs)offer signifi-cant potential as high energy density alternatives;nev-ertheless,their performance is hindered by the slow desolvation process of electrolytes,particularly at low temperatures(LT),leading to low coulombic efficiency and limited cycle ***,it is essential to opti-mize the solvation structure thereby achieving a rapid desolvation process in LMBs at ***,we introduce branch chain-rich diisopropyl ether(DIPE)into a 2.5 M li bis(fluorosulfonyl)imide dipropyl ether(DPE)elec-trolyte as a co-solvent for high-performance LMBs at-20℃.The incorporation of DIPE not only enhances the disorder within the electrolyte,but also induces a steric hindrance effect form DIPE’s branch chain,excluding other solvent molecules from li+solvation *** of these factors contribute to the weak interactions between li^(+)and solvent molecules,effectively reducing the desolvation energy of the ***,li(50μm)||LFP(mass loading~10 mg cm^(-2))cells in DPE/DIPE based electrolyte demonstrate stable performance over 650 cycles at-20℃,delivering 87.2 mah g^(-1),and over 255 cycles at 25℃ with 124.8 mah g^(-1).DIPE broadens the electrolyte design from molecular structure considera-tions,offering a promising avenue for highly stable LMBs at LT.

关键词： Solvation structure li metal battery Low temperature Steric hindrance Disorder