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Photoredox catalytic alkylarylation of alkynes with arylsulfonylacetate as bifunctional reagent

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Science China Chemistry 2024年第6期67卷 2022-2028页

作者： Chonglong He Min Wang Yulong Wang Lirong Zhao Youkang Zhou Keyuan Zhang Shenyu Shen Yaqiong Su Xin-Hua Duan le liu School of Chemistry Engineering Research Center of Energy Storage Materials and DevicesMinistry of EducationXi’an Key Laboratory of Sustainable Energy Material ChemistryXi’an Jiaotong UniversityXi’an710049China

Difunctionalization of alkynes represents a powerful and straightforward approach to the synthesis of complex molecules.However,the radical difunctionalization of alkynes mediated by bifunctional reagents remains challenging and underexplored,despite significant progress having been made in alkene difunctionalization.Here,we report a novel arylsulfonylacetate skeleton in which aryl rings are attached to acetates through SO_(2),serving as a powerful bifunctional reagent for the alkylarylation of alkynes via vinyl-radical intermediate under photoredox conditions.This modular bifunctional reagent enables the simultaneous incorporation of a wide range of functional groups,including(hetero)aryl ring and alkyl carboxylate into alkynes,resulting in synthetically valuable all-carbon tetrasubstituted alkene derivatives.This transformation is distinguished by its redox-neutral nature,readily accessible starting materials,compatibility with diverse functional groups and its capacity to facilitate convergent synthesis.The utility of this approach was further demonstrated by the late-stage functionalization of complex molecules and the preparation of fluorescent molecules and anti-cancer drugs.

关键词： bifunctional reagent photoredox catalysis Smiles rearrangement alkylarylation tetrasubstituted acyclic all-carbon olefins

Sensitivity impacts owing to the variations in the type of zero-range pairing forces on the fission properties using the density functional theory

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Nuclear Science and Techniques 2024年第3期35卷 198-207页

作者： Yang Su Ze-Yu Li Li-le liu Guo-Xiang Dong Xiao-Bao Wang Yong-Jing Chen China Nuclear Data Center China Institute of Atomic EnergyBeijing 102413China School of Science Huzhou UniversityHuzhou 313000China

Using the Skyrme density functional theory,potential energy surfaces of^(240)Pu with constraints on the axial quadrupole and octupole deformations(q_(20)and q_(30))were calculated.The volume-like and surface-like pairing forces,as well as a combination of these two forces,were used for the Hartree–Fock–Bogoliubov approximation.Variations in the least-energy fission path,fission barrier,pairing energy,total kinetic energy,scission line,and mass distribution of the fission fragments based on the different forms of the pairing forces were analyzed and discussed.The fission dynamics were studied based on the timedependent generator coordinate method plus the Gaussian overlap approximation.The results demonstrated a sensitivity of the mass and charge distributions of the fission fragments on the form of the pairing force.Based on the investigation of the neutron-induced fission of^(239)Pu,among the volume,mixed,and surface pairing forces,the mixed pairing force presented a good reproduction of the experimental data.

关键词： Nuclear fission Density functional theory Pairing force Potential energy surfaces Fission fragment distribution

ZIF-derived holey electrode with enhanced mass transfer and N-rich catalytic sites for high-power and long-life vanadium flow batteries

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Journal of Energy Chemistry 2022年第9期31卷 545-553,I0015页

作者： Yongbin liu Lihong Yu Xin liu le liu Jingyu Xi Institute of Materials Research Shenzhen International Graduate SchoolTsinghua UniversityShenzhen 518055GuangdongChina School of Materials&Environmental Engineering Shenzhen PolytechnicShenzhen 518055GuangdongChina

Electrode materials with good redox kinetics,excellent mass transfer characteristics and ultra-high stability play a crucial role in reducing the life-cycle cost and prolonging the maintenance-free time of the vanadium flow batteries(VFB).Herein,a nitrogen-doped porous graphite felt electrode(N-PGF)is proposed by growing ZIF-67 nanoparticles on carbon fibers and then calcinating and acid etching.The multi-scale structure of“carbon fiber gap(electrolyte flow),micro/nano pore(active species diffusion)and Nitrogen active center(reaction site)”in N-PGF electrode effectively increases the catalytic sites and promotes mass transfer characteristics.Reasonable electrode design makes the battery show excellent rate performance and ultra-high cycling stability.The peak power density of the battery reaches 1006 mW cm^(-2).During 1000 cycles at 150 mA cm^(-2),the average discharge capacity and average discharge energy of N-PGF increase substantially by 11.6%and 23.4%compared with the benchmark thermal activated graphite felt,respectively.More excitingly,after ultra-long term(5000 cycles)operation at an ultra-high current density(300 mA cm^(-2)),N-PGF exhibits an unprecedented energy efficiency retention(99.79%)and electrochemical performance stability.

关键词： Vanadium flow battery Multi-scale pore electrode Graphite felt Nitrogen-doping Cycling stability

Human impact on current environmental state in Chinese lakes

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Journal of Environmental Sciences 2023年第4期126卷 297-307页

作者： Qianhong Wang Yun Li le liu Suzhen Cui Xia liu Feizhou Chen Erik Jeppesen State Key Laboratory of Lake Science and Environment Nanjing Institute of Geography and LimnologyChinese Academy of SciencesNanjing 210008China University of Chinese Academy of Sciences Beijing 100049China Sino-Danish Centre for Education and Research(SDC) Beijing 100049China Department of Ecoscience Aarhus UniversitySilkeborg 8600Denmark Limnology Laboratory Department of Biological Sciences and Centre for Ecosystem Research and ImplementationMiddle East Technical UniversityAnkaraTurkey Institute of Marine Sciences Middle East Technical UniversityMersinTurkey

Anthropogenic and natural disturbance to inland aquatic ecosystems displays a notable spatial difference, yet data to measure these differences are scarce. This study encompasses 217 lakes distributed over five lake regions of China and elucidates the environmental factors determining the spatial variability of the water quality and trophic status. A significant correlation between human modification index in surrounding terrestrial systems(HMT)and trophic status of lake ecosystems(TSI) was found, and the regression slope in each region was similar except in the Qinghai-Tibet Plateau region. It was further noted that the pattern of environmental factor network(EF network) differed among freshwater and saline lakes. The EF network was complex for freshwater lakes in less human-influenced areas, but intensive man-made influence disrupted most relationships except for those between total nitrogen, total phosphorus, chlorophyll-a, and water turbidity. As for regions including saline lakes, correlations among water salinity and organic forms of carbon and nitrogen were apparent. Our results suggest that HMT and EF network can be useful indicators of the ecological integrity of local lake ecosystems, and integrating spatial information on a large scale provides conservation planners the option for evaluating the potential risk on inland aquatic systems.

关键词： Anthropogenic impact Trophic state Lake Spatial patterns Environmental management

Evaluation method for assessing the auxiliary service transaction mechanism in regional power markets

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Global Energy Interconnection 2023年第2期6卷 238-252页

作者： le liu Xueyu Chen Dexin Li Chang liu Dunnan liu Genzhu Li Jilin Power Exchange Center Co. Ltd.Changchun 130021P.R.China Electric Power Research Institute of Jilin Province Changchun 130021P.R.China School of Economics and Management North China Electric Power UniversityBeijing 102206P.R.China

Accurate and seamless auxiliary services in the power market can guarantee smooth and continuous power system operation. China’s new round of power system reform has entered a critical period, and reform implementation requires comprehensive improvements in the maturity of the supporting auxiliary service market. This study reviews the development status and evolution path of the European unified power market and the US regional power market, provides experience for the development of China’s regional power market, then identifies the key influencing factors of auxiliary service trading mechanism design in regional power markets. To analyze the rationality of the auxiliary service trading evaluation index, this paper established an evaluation model for assessing regional power markets. Using combined weight optimization, the gray correlation TOPSIS method was applied to comprehensively evaluate auxiliary service trading in the regional power market. Finally, the application of the proposed evaluation method was briefly analyzed to examine four regional power markets in China and evaluate the effectiveness of current market construction in different regions and provide suggestions for future market construction.

关键词： Power market Auxiliary services Transaction mechanism Evaluation index Evaluation model

Selective hydrogenation of glucose to sorbitol with tannic acid-based porous carbon sphere supported Ni-Ru bimetallic catalysts

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Green Energy & Environment 2023年第6期8卷 1719-1727页

作者： Ran Xi Yiwei Tang Richard lee Smith Jr Xiaoning liu le liu Xinhua Qi College of Environmental Science and Engineering Nankai UniversityNo.38Tongyan RoadJinnan DistrictTianjin300350China Graduate School of Environmental Studies Tohoku UniversityAramaki Aza Aoba 6-6-11AobaSendai980-8579Japan National-Local Joint Engineering Research Center of Biomass Resource Utilization Nankai UniversityNo.38Tongyan RoadJinnan DistrictTianjin300350China

Ni-Ru bimetallic porous carbon sphere(Ni-Ru@PCS) catalysts were synthesized via formaldehyde-assisted, metal-coordinated crosslinking sol-gel chemistry, in which biomass-derived tannic acid and F127 surfactant were used as carbon precursor and soft template, respectively, and Ni2+and Ru3+were used as cross-linkers. In the developed method, Ni-Ru particles became uniformly dispersed in the carbon skeleton due to strong coordination bonds between metal ions(Ni2+and Ru^(3+)) and tannic acid molecules and bimetal interactions. The as-synthesized Ni-Ru10:1@PCS catalyst with a loading Ni:Ru mole ratio of 10:1 was applied for the selective hydrogenation of glucose to sorbitol, and provided 99% glucose conversion with a sorbitol selectivity of 100% at 140℃ in 150 min reaction time and exhibited good stability and recyclability in which sorbitol yield remained at 98% after 4 cycles with little or no metal agglomeration. The catalyst was applied to glucose solutions as high as 20 wt% with 97% sorbitol yields being obtained at 140℃ in 20 h. The developed bimetallic porous carbon sphere catalysts take advantage of sustainably-derived materials in their structure and are applicable to related biomass conversion reactions.

关键词： Tannic acid Ni–Ru bimetal Glucose Sorbitol Catalytic hydrogenation

A contradictory phenomenon of thicken pericardium and cardiac compression without inferior vena cava dilation:sign of IVC escape

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Journal of Geriatric Cardiology 2024年第5期21卷 583-587页

作者： Tie-Nan CHEN Shuang ZHAO Shuai QIAO Yong-Yong HAN Qing liu Chang-le liu Guang-Ping LI Tong liu Hua-Ying FU Department of Cardiovascular Surgery Second Hospital of Tianjin Medical UniversityTianjinChina Department of Cardiology Tianjin Key Laboratory of Ionic-Molecular Function of Cardiovascular DiseaseTianjin Institute of Cardi-ologyThe Second Hospital of Tianjin Medical UniversityTianjinChina Department of Oncology Second Hospital of Tianjin Medical UniversityTianjinPeople's Republic of China

A 77-year-old female presented with shortness of breath and tightness of chest was admitted.Her past medical history included hypertension and she has been taking nifedipine regularly.Two years before,she was diagnosed with pericardial effusion(Figure 1)and had pericardiocentesis drainage.On physical examination,her blood pressure was 151/100 mm-Hg and her pulse rate was 91 beats/min.

关键词： admitted cardiac thick

The unconventional prefoldin RPB5 interactor mediates the gravitropic response by modulating cytoskeleton organization and auxin transport in Arabidopsis

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Journal of Integrative Plant Biology 2022年第10期64卷 1916-1934页

作者： Yi Yang Fang liu le liu Mingyue Zhu Jinfeng Yuan Yan‐Xia Mai Jun‐Jie Zou Jie le Yonghong Wang Klaus Palme Xugang Li Yong Wang Long Wang State Key Laboratory of Crop Biology College of Life SciencesShandong Agricultural UniversityDaizong Street 61Tai'an 271018China Shandong Provincial Key Laboratory of Biophysics Institute of BiophysicsDezhou UniversityDezhou 253023China Sino‐German Joint Research Center on Agricultural Biology College of Life SciencesShandong Agricultural UniversityDaizong Street 61Tai'an 271018China Faculty of Biology Institute of Biology II/Molecular Plant PhysiologyAlbert‐Ludwigs‐University of FreiburgSchänzlestrasse 1Freiburg D‐79104Germany National Key Laboratory of Plant Molecular Genetics(NKLPMG) CAS Center for Excellence in Molecular Plant SciencesInstitute of Plant Physiology and Ecology(SIPPE)Chinese Academy of Sciences(CAS)Shanghai 200032China Biotechnology Research Institute Chinese Academy of Agricultural SciencesBeijing 100081China Key Laboratory of Plant Molecular Physiology CAS Center for Excellence in Molecular Plant SciencesInstitute of BotanyChinese Academy of SciencesBeijing 100093China University of Chinese Academy of Sciences Beijing 100049China

Gravity-induced root curvature involves the asymmetric distribution of the phytohormone auxin.This response depends on the concerted activities of the auxin transporters such as PIN-FORMED(PIN)proteins for auxin efflux and AUXIN RESISTANT 1(AUX1)for auxin influx.However,how the auxin gradient is established remains elusive.Here we identified a new mutant with a short root,strong auxin distribution in the lateral root cap and an impaired gravitropic response.The causal gene encoded an Arabidopsis homolog of the human unconventional prefoldin RPB5 interactor(URI).At URI interacted with prefoldin 2(PFD2)and PFD6,twoβ-type PFD members that modulate actin and tubulin patterning in roots.The auxin reporter DR5_(rev):GFP showed that asymmetric auxin redistribution after gravistimulation is disordered in aturi-1 root tips.Treatment with the endomembrane protein trafficking inhibitor brefeldin A indicated that recycling of the auxin transporter PIN2 is disrupted in aturi-1 roots as well as in pfd mutants.We propose that At URI cooperates with PFDs to recycle PIN2and modulate auxin distribution.

关键词： Arabidopsis auxin cytoskeleton PIN2 prefoldin(PFD) unconventional prefoldin RPB5 interactor(URI)

Guazia, the earliest ovule without cupule but with unique integumentary lobes

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National Science Review 2022年第4期9卷 13-20页

作者： De-Ming Wang le liu Yi Zhou Min Qin Mei-Cen Meng Yun Guo Jin-Zhuang Xue Key Laboratory of Orogenic Belts and Crustal Evolution Department of GeologyPeking University School of Geoscience and Surveying Engineering China University of Mining and Technology (Beijing) Institute of Geology and Paleontology Linyi University Institute of Deep Time Terrestrial Ecology Institute of PalaeontologyYunnan Key Laboratory of Earth System ScienceYunnan University

The earliest ovules in the Late Devonian(Famennian) are surrounded by a cupule that is involved in both protection and pollination, and generally have free integumentary lobes. Here we report a new taxon from the Famennian of China, Guazia dongzhiensis gen. et sp. nov. The terminally borne ovule is apparently acupulate(without cupule) and has four radially arranged wing-like integumentary lobes that are extensively fused, and folded lengthwise and inwards. Guazia provides evidence that not all Devonian seeds possess a cupule and it increases their diversity in integumentary lobes. This genus also suggests that the integuments develop new functions, probably including wind dispersal at the expense of the cupules.

关键词： ovule cupule integument Devonian seed plants