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Ni-catalyzed cross-electrophile alkyl-alkyl coupling reactions

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Science China Chemistry 2025年

作者： Li-Xu You Lan Tian chun-Ling guo Shun-Xi Li Yu-Cheng liu Yu-Long Li Wei Shu College of Chemistry and Environmental Engineering Key Laboratory of Green Catalysis of Higher Education Institutes of Sichuan Sichuan University of Science and Engineering guangming Advanced Research Institute Shenzhen Grubbs Institute Department of Chemistry and Guangdong Provincial Key Laboratory of Catalysis Southern University of Science and Technology

Introducing saturated carbon-carbon bonds into organic molecules significantly increases the three-dimensional configuration,thus altering the physical and chemical properties as well as the functions of molecules. Transition-metal-catalyzed carboncarbon cross-couplings represent one of the most straightforward, efficient and modular alternatives to build saturation in a single step. However, the efficient construction of alkyl-alkyl bonds remains a formidable challenge due to the precise manipulation of multiple alkyl metallic intermediates as well as associated competitive side reactions and selectivity control. Over the past years, Ni-catalyzed cross-coupling under reductive conditions has gained more and more attention for alkyl-alkyl crosscoupling partially attributing to the low-valent state of metal centers under reducing conditions, which suppresses the competitive β-hydride elimination process, thus facilitating the formation of alkyl-alkyl bonds. In this review, the initiative and progress of Ni-catalyzed cross-electrophile alkyl-alkyl cross-coupling, including the efforts in racemic and enantioselective formation of alkyl-alkyl bonds, have been summarized and discussed. Moreover, the challenges and further opportunities in this area have also been discussed.

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基于刻蚀处理的池沸腾传热性能实验研究

原子与分子物理学报 2025年第3期42卷 180-188页

作者：王菊萍匡纯纯刘妮上海理工大学制冷技术研究所上海200093

为探究刻蚀处理铜板表面对池沸腾传热性能的改善效果,搭建了可视化实验平台,制备不同刻蚀浓度和刻蚀时间处理的表面,采用去离子水为工质,进行饱和池沸腾实验.结果表明,氨水刻蚀浓度越大,表面的换热性能越强,氨水刻蚀时间越长,表面换热... 详细信息

为探究刻蚀处理铜板表面对池沸腾传热性能的改善效果,搭建了可视化实验平台,制备不同刻蚀浓度和刻蚀时间处理的表面,采用去离子水为工质,进行饱和池沸腾实验.结果表明,氨水刻蚀浓度越大,表面的换热性能越强,氨水刻蚀时间越长,表面换热性能越强.热流密度为43.2 W/cm^(2)时,0.05 mol/L氨水刻蚀4 h表面、0.05 mol/L氨水刻蚀5 h表面、0.05 mol/L氨水刻蚀8 h表面、0.03 mol/L氨水刻蚀4 h表面、0.05 mol/L氨水刻蚀4 h表面和0.10 mol/L氨水刻蚀4 h表面上的换热系数分别提高了46%、92%、105%、36%、45%、78%.此外,对其表面进行表征,结果说明了其优异的沸腾性能.刻蚀处理增强了表面粗糙度,有效面积,从而促进液体的补充,能够在较小的过热度下达到更高的临界热流密度.可视化研究结果表明,刻蚀表面具有更多的成核位点,更小的气泡离开直径和离开频率.这些结果显示出刻蚀表面强化池沸腾换热的潜力.

关键词：池沸腾刻蚀传热性能气泡动力学微纳结构表面

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Sulfolane‑Based Flame‑Retardant Electrolyte for High‑Voltage Sodium‑Ion Batteries

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Nano-Micro Letters 2025年第2期17卷 498-516页

作者： Xuanlong He Jie Peng Qingyun Lin Meng Li Weibin Chen Pei liu Tao Huang Zhencheng Huang Yuying liu Jiaojiao Deng Shenghua Ye Xuming Yang Xiangzhong Ren Xiaoping Ouyang Jianhong liu Biwei Xiao Jiangtao Hu Qianling Zhang graphene Composite Research Center College of Chemistry and Environmental EngineeringShenzhen UniversityShenzhen 518060People’s Republic of China Center of Electron Microscopy State Key Laboratory of Silicon and Advanced Semiconductor MaterialsSchool of Materials Science and EngineeringZhejiang UniversityHangzhou 310027People’s Republic of China gRINM(guangdong)Research Institute for Advanced Materials and Technology FoshanGuangdong 528051People’s Republic of China College of Energy Engineering Zhejiang UniversityHangzhouZhejiang 310027People’s Republic of China School of Materials Science and Engineering Xiangtan UniversityXiangtan 411105People’s Republic of China Shenzhen Eigen-Equation graphene Technology Co.Ltd Shenzhen 518000People’s Republic of China

Sodium-ion batteries hold great promise as next-generation energy storage ***,the high instability of the electrode/electrolyte interphase during cycling has seriously hindered the development of *** particular,an unstable cathode–electrolyte interphase(CEI)leads to successive electrolyte side reactions,transition metal leaching and rapid capacity decay,which tends to be exacerbated under high-voltage ***,constructing dense and stable CEIs are crucial for high-performance *** work reports localized high-concentration electrolyte by incorporating a highly oxidation-resistant sulfolane solvent with non-solvent diluent 1H,1H,5H-octafluoropentyl-1,1,2,2-tetrafluoroethyl ether,which exhibited excellent oxidative stability and was able to form thin,dense and homogeneous *** excellent CEI enabled the O3-type layered oxide cathode NaNi_(1/3)Mn_(1/3)fe_(1/3)O_(2)(NaNMF)to achieve stable cycling,with a capacity retention of 79.48%after 300 cycles at 1 C and 81.15%after 400 cycles at 2 C with a high charging voltage of 4.2 *** addition,its nonflammable nature enhances the safety of *** work provides a viable pathway for the application of sulfolane-based electrolytes on SIBs and the design of next-generation high-voltage electrolytes.

关键词： Sodium-ion batteries Sulfolane-based electrolyte High voltage Layered oxide cathode Flame retardant

Deciphering Water Oxidation Catalysts:The Dominant Role of Surface Chemistry over Reconstruction Degree in Activity Promotion

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Nano-Micro Letters 2025年第3期17卷 340-354页

作者： Li An Jianyi Li Yuanmiao Sun Jiamin Zhu Justin Zhu Yeow Seow Hong Zhang Nan Zhang Pinxian Xi * Zhichuan JXu chun‑Hua Yan State Key Laboratory of Applied Organic Chemistry Key Laboratory of Nonferrous Metal Chemistry and Resources Utilization of Gansu ProvinceFrontiers Science Center for Rare IsotopesCollege of Chemistry and Chemical EngineeringLanzhou UniversityLanzhou 730000People’s Republic of China School of Materials Science and Engineering Nanyang Technological UniversitySingapore 639798Singapore Faculty of Materials Science and Energy Engineering Institute of Technology for Carbon NeutralityShenzhen Institute of Advanced TechnologyChinese Academy of SciencesShenzhen 518055People’s Republic of China Key Laboratory of Electromagnetic Materials and Devices National Center for International Research On Photoelectric and Energy MaterialsSchool of Materials and EnergyElectron Microscopy CenterYunnan UniversityKunming 650091People’s Republic of China State Key Laboratory of Baiyunobo Rare Earth Resource Researches and Comprehensive Utilization Baotou Research Institute of Rare EarthsBaotou 014030People’s Republic of China Beijing National Laboratory for Molecular Sciences State Key Laboratory of Rare Earth Materials Chemistry and ApplicationsPKU‑HKU Joint Laboratory in Rare Earth Materials and Bioinorganic ChemistryPeking UniversityBeijing 100871People’s Republic of China

Water splitting hinges crucially on the availability of electrocatalysts for the oxygen evolution *** surface reconstruction has been widely observed in perovskite catalysts,and the reconstruction degree has been often correlated with the activity ***,a systematic study on the roles of fe substitution in activation of perovskite LaNiO_(3)is *** substituting fe content influences both current change tendency and surface reconstruction ***_(0.9)fe_(0.1)O_(3)is found exhibiting a volcano-peak intrinsic activity in both pristine and reconstructed among all substituted perovskites in the LaNi_(1-x)fe_(x)O_(3)(x=0.00,0.10,0.25,0.50,0.75,1.00)*** reconstructed LaNi_(0.9)fe_(0.1)O_(3)shows a higher intrinsic activity than most reported Nife-based ***,density functional theory calculations reveal that fe substitution can lower the O 2p level,which thus stabilize lattice oxygen in LaNi0.9fe0.1O3 and ensure its long-term ***,it is vital interesting that activity of the reconstructed catalysts relied more on the surface chemistry rather than the reconstruction *** effect of fe on the degree of surface reconstruction of the perovskite is decoupled from that on its activity enhancement after surface *** finding showcases the importance to customize the surface chemistry of reconstructed catalysts for water oxidation.

关键词： Oxygen evolution reaction Perovskite oxides Doping Activation and reconstruction

Preparation of feCoNi medium entropy alloy from fe^(3+)-Co^(2+)-Ni^(2+)solution system

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International Journal of Minerals,Metallurgy and Materials 2025年第1期32卷 92-101页

作者： Zongyou Cheng Qing Zhao Mengjie Tao Jijun Du Xingxi Huang Chengjun liu Key Laboratory for Ecological Metallurgy of Multimetallic Mineral(Ministry of Education) Northeastern UniversityShenyang 110819China School of Metallurgy Northeastern UniversityShenyang 110819China Engineering Research Center of Frontier Technologies for Low-carbon Steelmaking(Ministry of Education) Shenyang 110819China

In recent years,medium entropy alloys have become a research hotspot due to their excellent physical and chemical *** controlling reasonable elemental composition and processing parameters,the medium entropy alloys can exhibit similar properties to high entropy alloys and have lower *** this paper,a feCoNi medium entropy alloy precursor was prepared via sol-gel and coprecipitation methods,respectively,and feCoNi medium entropy alloys were prepared by carbothermal and hydrogen *** phases and magnetic properties of feCoNi medium entropy alloy were *** showed that feCoNi medium entropy alloy was produced by carbothermal and hydrogen reduction at 1500℃.Some carbon was detected in the feCoNi medium entropy alloy prepared by carbothermal *** alloy prepared by hydrogen reduction was uniform and showed a relatively high ***,the hydrogen reduction product exhibited better saturation magnetization and lower coercivity.

关键词： medium entropy alloy sol-gel co-precipitation carbothermal hydrogen reduction

Effects of water level variations on the water quality of Huayang Lakes, China

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Journal of geographical Sciences 2025年第1期 173-188页

作者： AN Lesheng liu chun FAN Zhongya LIAO Kaihua WANg Wencai WANg Nan School of Resources and Environment Anqing Normal University South China Institute of Environmental Sciences Ministry of Ecology and Environment The Key Laboratory of Watershed geographic Sciences Nanjing Institute of Geography and LimnologyCAS

To explore water level variations and their dynamic influence on the water quality of Huayang Lakes, the water level from 1967 to 2023 and water quality from 2015 to 2023 were analyzed using the Mann–Kendall trend test, box plots, and violin plots. The results show a notable hydrological rhythm of water level alternation between dry and flood seasons in Huayang Lakes, with an average water level of 12.82 m and a monthly range of 11.21–17.24m. Since 2017, the water level of Huayang Rivers has shown a decreasing trend of –0.02 m/*** phosphorus(TP) has become the primary pollutant. The TP concentrations in Longgan Lake(the largest lake) during the dry, rising, flood, and retreating seasons from 2015 to 2023were 0.083, 0.061, 0.050, and 0.059 mg/L, respectively. The effect of water level on TP was mainly observed during the low-water period. When the water level in the dry season rose to 12.25 and 13.00 m, the percentage of TP exceeding 0.1 mg/L in Longgan Lake decreased to 55.8% and 33.3%, respectively. During the dry season, wind and wave disturbances caused the release of endogenous phosphorus in Huayang Lakes. This led to drastic fluctuations in TP concentration, reducing the correlation between water level and TP. When external control is limited, the water level during the dry season should be maintained between 12.25 and 13.0 m. Additionally, it is necessary to accelerate the restoration of submerged macrophyte species(such as Hydrilla verticillata and Vallisneria natans) in the Huayang Rivers.

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绿原酸对中性粒细胞功能及胞外诱捕网形成的影响及机制

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中国药理学通报 2025年第1期41卷 101-107页

作者：杨运刘娅王翠彭春红贵州中医药大学第二临床医学院贵州贵阳550025 七星关区中医妇幼集团医院贵州毕节551700 毕节市中医医院贵州毕节551700 贵州医科大学临床医学院贵州贵阳550025 贵州省人民医院呼吸与危重医学科贵州贵阳550002 国家卫健委肺脏免疫性疾病重点实验室贵州贵阳550002

目的探究绿原酸(chlorogenic acid,CgA)对中性粒细胞(neutrophil,NEU)功能及中性粒细胞胞外诱捕网(neutrophil extracellular traps,NETs)形成的影响及机制。方法从小鼠骨髓中分离并纯化NEU;将NEU与CgA共培养,通过CCK-8法筛选共培养适合的干预浓度;检测NEU迁移能力、髓过氧化物酶(MPO)以及脱颗粒弹性蛋白酶(NE)、基质金属蛋白酶9(MMP-9)的水平观察CgA对NEU功能的影响;免疫荧光法观察NETs的主要结构组蛋白H3及DNA骨架,以及检测NEU释放的游离DNA(cf-DNA)含量,观察NETs的形成情况;检测NEU产生的活性氧(ROS)水平,以确定CgA是否影响NEU释放NETs过程中的ROS的生成。结果CgA在浓度为100、200、400μmol·L^(-1)时对NEU活性有明显抑制作用(PgA(100、200、400μmol·L^(-1))干预后,细胞迁移能力及MPO、NE、MMP-9分泌量增加(PgA能够增强NEU功能及促进NETs的形成,可能与促进细胞内ROS水平增加有关。

关键词：绿原酸中性粒细胞胞外诱捕网免疫抗菌活性氧

Supersymmetry for fermion Masses

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Communications in Theoretical Physics 2007年第6期47卷 1088-1098页

作者： liu chun Institute of Theoretical Physics the Chinese Academy of Sciences P.O. Box 2735 Beijing 100080 China

It is proposed that supersymmetry （SUSY） may be used to understand fermion mass hierarchies. A family symmetry ZSL is introduced, which is the cyclic symmetry among the three generation SU（2） doublets. SUSY breaks at a high energy scale - 10^11 geV. The electroweak energy scale- 100 geV is unnaturally small No additional global symmetry, like the R-parlty, is imposed. The Yukawa couplings and R-parity violating couplings all take their natural values, which are О（10^0 -10^-2）. Under the family symmetry, only the third generation charged ferrnions get their masses. This family symmetry is broken in the soft SUSY breaking terms, which result in a hierarchical pattern of the fermion masses. It turns out that for the charged leptons, the r mass is from the Higgs vacuum expectation value （VEV） and the sneutrino VEVs, the muon mass is due to the sneutrino VEVs, and the electron gains its mass due to both ZZL and SUSY hreaking. The large neutrino mixing are produced with neutralinos playing the partial role of right-handed neutrinos. │Ve3│, which is for Ve-Vr mixing, is expected to be about 0.1. For the quarks, the third generation masses are from the Higgs VEVs, the second generation masses are from quantum corrections, and the down quark mass due to the sneutrino VEVs. It explains me/ms, ms/me, md 〉 mu and so on. Other aspects of the model are discussed.

关键词： fermion mass family symmetry supersymmetry

Multiobjective evolutionary algorithm for dynamic nonlinear constrained optimization problems

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Journal of Systems Engineering and Electronics 2009年第1期20卷 204-210页

作者： liu chun'an Wang Yuping Dept. of Mathematics Baoji Univ. of Arts and Science Baoji 721013 P. R. China School of Computer Engineering and Technology Xidian Univ. Xi'an 710071 P. R. China

A new method to solve dynamic nonlinear constrained optimization problems （DNCOP） is proposed. First, the time （environment） variable period of DNCOP is divided into several equal subperiods. In each subperiod, the DNCOP is approximated by a static nonlinear constrained optimization problem （SNCOP）. Second, for each SNCOP, inspired by the idea of multiobjective optimization, it is transformed into a static bi-objective optimization problem. As a result, the original DNCOP is approximately transformed into several static bi-objective optimization problems. Third, a new multiobjective evolutionary algorithm is proposed based on a new selection operator and an improved nonuniformity mutation operator. The simulation results indicate that the proposed algorithm is effective for DNCOP.

关键词： dynamic optimization nonlinear constrained optimization evolutionary algorithm optimal solutions