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Chinese Chemical Letters 2008年第3期19卷 329-332页

作者： Cai Sheng Wu bao lin guo Yu Xin Sheng Jin Lan Zhang Institute of Materia Medica Chinese Academy of Medical Sciences Peking Union Medical College Beijing 100050 China Institute of Medicinal Plant Development Chinese Academy of Medical Sciences Peking Union Medical College Beijing 100094 China

In this paper, a sensitive and specific liquid chromatography-electrospray ionisation-mass spectrometry （LC-ESI-MS） method has been developed and validated for the identification and determination of seven flavonoids, namely epimedin A, epimedin B, epimedin C, icariin, sagittatoside B, 2＂-O-rhamnosyl icariside II, and baohuoside I in Epimedium from different sources.

关键词： Flavonoids Epimedium Liquid chromatography-electrospray ionization-mass spectrometry Quantitative determination

Novel Synthesis of Sol-gel Derived Nanosized Mullite Powder

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Chinese Journal of Aeronautics 2006年第B12期19卷 71-73页

作者： LIANG Long LI Jian-bao lin Hong guo Gang-feng HE Ming-sheng State Key Lab of New Ceramics and Fine Processing Dept of Materials Science and Engineering Tsinghua University Beijing 100084 China

Using hydrous aluminum chloride （AlCl3·6H2O） and silicon ethoxide （Si （OC2H5）4） as raw materials, a kind of nano-sized mullite powder was synthesized with the sol-gel process at the medium calcination temperature. The microstructures of the alumina-silica binary aerogel and calcined nano-sized materials were investigated by means of thermogravimetry-differential thermal analysis （TG-DTA）, scanning electron microscopy （SEM） and X-ray diffractometer （XRD）. The results show that the mullitization of Al2O3-SiO2 in gel starts from about 1 000℃ and its formation ofmullite takes place in the range of 1 100℃-1 250 ℃. The size of the nano-sized mullite powder calcined at 1 250 ℃ is measured to be about 30 nm.

关键词： mullite sol-gel synthesis temperature

XAS Study of Low Dimensional Dilute Magnetic Semiconductors

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功能材料信息 2016年第4期13卷 38-39页

作者： bao-lin guo Xi'an Jiaotong University

Electrically conducting polymers induce specific cellular responses at the molecular *** of the crucial limitations of the use of conducting polymers in tissue engineering is their inability to *** incorporation of conducting polymers into degradable polymers to obtain materials that are both electroactive and degradable is therefore

关键词：英语阅读理解生物材料

Electrochemical Cascade Annulation for the Synthesis of 3-Sulfanylquinoline Derivatives under Mild Conditions

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Chinese Journal of Chemistry 2024年第16期42卷 1833-1838页

作者： Ke Li Ming-Zhong guo Zhuo Chen Hao-Ran Li Weisi guo Ming Li lin-bao Zhang State Key Laboratory Base of Eco-Chemical Engineering College of Chemistry and Molecular EngineeringQingdao University of Science&TechnologyQingdaoShandong 266042China

An efficient electrochemical approach has been developed for the construction of 3-sulfanylquinoline derivatives by treating phenylethynylbenzoxazinanones with disulfides in an undivided *** protocol provided a convenient route to functionalized quinolines with good functional group ***,it does not require any metal catalysts or additives,furnishing a series of biologicalquinolines inmoderatetogoodyields.

关键词： Electrocatalysis Electrooxidation Annulation 3-Sulfany quinoline C3-thioetherification

Fullerenes and derivatives as electrocatalysts: Promises and challenges

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Green Energy & Environment 2024年第1期9卷 7-27页

作者： Kun guo Ning Li Lipiao bao Xing Lu State Key Laboratory of Materials Processing and Die&Mould Technology School of Materials Science and EngineeringHuazhong University of Science and TechnologyWuhan430074China

Carbon-based metal-free nanomaterials are promising alternatives to precious metals as electrocatalysts of key energy storage and conversion *** paramount signiﬁcance are the establishment of design principles by understanding the catalytic mechanisms and identifying the active *** from sp2-conjugated graphene and carbon nanotube,fullerene possesses unique characteristics that are growingly being discovered and exploited by the electrocatalysis *** instance,the well-deﬁned atomic and molecular structures,the good electron afﬁnity to tune the electronic structures of other substances,the intermolecular self-assembly into superlattices,and the on-demand chemical modiﬁcation have endowed fullerene with incomparable advantages as electrocatalysts that are otherwise not applicable to other carbon *** increasing studies are being reported on this intriguing topic,it is necessary to provide a state-of-the-art overview of the recent *** review takes such an initiative by summarizing the promises and challenges in the electrocatalytic applications of fullerene and its *** content is structured according to the composition and structure of fullerene,including intact fullerene(e.g.,fullerene composite and superlattices)and fullerene derivatives(e.g.,doped,endohedral,and disintegrated fullerene).The synthesis,characterization,catalytic mechanisms,and deﬁciencies of these fullerene-based materials are explicitly *** conclude it by sharing our perspectives on the key aspects that future efforts shall consider.

关键词： Fullerene Fullerene derivative Metal-free catalyst Structural defect Electrocatalyst

Fast and Adaptive Multi-Agent Planning under Collaborative Temporal Logic Tasks via Poset Products

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Research 2024年第2期2024卷 81-94页

作者： Zesen Liu Meng guo Weimin bao Zhongkui Li Deparment of Mechanics and Engineering Science College of EngineeringPeking UniversityBejing 0081 China Science and Technology Commission of China Aerospace Science and Technology Corporation Beijing 100048China

Efficient coordination and planning is essential for large-scale multi-agent systems that collaborate in a shared dynamic environment. Heuristic search methods or learning-based approaches often lack the guarantee on correctness and performance. Moreover, when the collaborative tasks contain both spatial and temporal requirements, e.g., as linear temporal logic (LTL) formulas, formal methods provide a verifiable framework for task planning. However, since the planning complexity grows exponentially with the number of agents and the length of the task formula, existing studies are mostly limited to small artificial cases. To address this issue, a new planning paradigm is proposed in this work for system-wide temporal task formulas that are released online and continually. It avoids two common bottlenecks in the traditional methods, i.e., (a) the direct translation of the complete task formula to the associated B點hi automaton and (b) the synchronized product between the B點hi automaton and the transition models of all agents. Instead, an adaptive planning algorithm is proposed, which computes the product of relaxed partially ordered sets (R-posets) on-the-fly and assigns these subtasks to the agents subject to the ordering constraints. It is shown that the first valid plan can be derived with a polynomial time and memory complexity with respect to the system size and the formula length. Our method can take into account task formulas with a length of more than 400 and a fleet with more than 400 agents, while most existing methods fail at the formula length of 25 within a reasonable duration. The proposed method is validated on large fleets of service robots in both simulation and hardware experiments.

关键词： hardware service system

Lithium-induced graphene layer containing Li_(3)P alloy phase to achieve ultra-stable electrode interface for lithium metal anode

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Rare Metals 2024年第2期43卷 562-574页

作者： Jia-Xin Chen guo-Qiang Zhang Xian-Ying Qin Kui lin Zi-Jin Yang Ge-Meng Liang Yue Xia guo-Bin Zhang Hai-Kun Wu Qiu-Chan Cai Hai lin bao-Hua Li Shenzhen Key Laboratory on Power Battery Safety Research and Shenzhen Geim Graphene Center Tsinghua Shenzhen International Graduate SchoolShenzhen518055China Shenzhen Graphene Innovation Center Co. Ltd.Shenzhen518107China School of Chemical Engineering and Advanced Materials The University of AdelaideAdelaideSA5005Australia Department of Chemistry City University of Hong KongHong Kong990077China

Uncontrolled growth of lithium dendrite will lead to low Coulombic efficiency and poor cycle stability,which hinders the commercialization of lithium metal ***,a novel modified lithium anode with reduced graphene oxide conductive network containing trace lithiophilic phosphorus(P-rGO/Cu)is prepared by electrospraying technique combined with heat treatment *** rGO layer has a concave and undulating conductive structure,which can significantly improve the effective electrical contact between lithium metal and the current collector,speed up the kinetics of interfacial electron transport and reaction,and improve the resistance of the negative electrode to the internal stress caused by volume change of the lithium,which is advantageous for the stability of the SEI *** extremely small and uniformly distributed red phosphorus element avoids the volume change caused by lithiation to the maximum *** two-phase compound Li_(3)P obtained by alloying P with Li can directionally induce the homogeneous nucleation and dense deposition of lithium metal,address the issue of lithium dendrites and extend the cycle life of the *** obtained P-rGO/Cu exhibits excellent electrochemical performance with an average Coulombic efficiency(CE)of 98%at a current density of 1 mA·cm^(−2) for 400 cycles,and the capacity retention rate of the full cell matched with lithium iron phosphate(LFP)is 83%after 400 cycles at 1C.

关键词： Lithium anode Dendrite-free Lithiophilicity Induced nucleation deposition

Electrochemical Reduction of Benzo[b]thiophene 1,1-Dioxides with HFIP as Hydrogen Donor

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Chinese Journal of Chemistry 2024年第6期42卷 585-591页

作者： Ming-Zhong guo Mei-Jin Mou Zhuo Chen Shao-Fei Ni Ming Li Li-Rong Wen lin-bao Zhang State Key Laboratory Base of Eco-Chemical Engineering College of Chemistry and Molecular EngineeringQingdao University of Science & TechnologyQingdaoShandong266042 China Department of Chemistry and Key Laboratory for Preparation and Application of Ordered Structural Materials of Guangdong Province Shantou UniversityShantouGuangdong515063 China

A straightforward electrochemical reduction of benzo[b]thiophene 1,1-dioxides with HFIP as the hydrogen donor has been reported in an undivided cell under metal-free ***,the tolerance of various functional groups and ... 详细信息

关键词： Electrochemistry Reduction Benzo[b]thiophene 1,1-dioxides Deuterium Hydrogen source

New process for treating boron-bearing iron ore by flash reduction coupled with magnetic separation

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International Journal of Minerals,Metallurgy and Materials 2024年第3期31卷 473-484页

作者： Qipeng bao Lei guo Hong Yong Sohn Haibin Zuo Feng Liu Yongliang Gao Zhancheng guo State Key Laboratory of Advanced Metallurgy University of Science and Technology BeijingBeijing 100083China Department of Materials Science&Engineering University of UtahUtah 84112USA China ENFI Engineering Corporation Beijing 100038China

Boron is an important industrial raw material often sourced from minerals containing different compounds that cocrystallize,which makes it difficult to separate the mineral phases through conventional *** study proposed a new treatment called flash reduction-melting separation(FRMS)for boron-bearing iron *** this method,the concentrates were first flash-reduced at the temperature under which the particles melt,and the slag and the reduced iron phases disengaged at the particle *** reduc-tion and melting effects were achieved above 1550℃.The B_(2)O_(3) content in the separated slag was over 18wt%,and the B content in the iron was less than 0.03wt%.The proposed FRMS method was tested to investigate the effects of factors such as ore particle size and tem-perature on the reduction and melting steps with and without pre-reducing the raw *** mineral phase transformation and morphology evolution in the ore particles during FRMS were also comprehensively analyzed.

关键词： ludwigite boron-bearing iron concentrate flash reduction melting separation boron

Recent Advances in Pd-Catalyzed Reactions Involving the “On-Water” Mechanism

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Chinese Journal of Chemistry 2024年第5期42卷 533-542页

作者： Dong Wei guo-Qiang lin State Key Laboratory of Systems Medicine for Cancer Shanghai Cancer InstituteShanghai Key Laboratory of Systems Regulation and Clinical Translation for CancerRen Ji HospitalShanghai Jiao Tong University School of MedicineShanghai200127 China State Key Laboratory of Chemical Biology Shanghai Institute of Organic ChemistryUniversity of Chinese Academy of SciencesChinese Academy of SciencesShanghai200032 China

As the chemical industry grapples with the need for more eco-friendly practices,the use of water as a reaction medium is gaining attraction in organic *** mini-review delves into Pd-catalyzed reactions that utilize the "on-water" mechanism,spanning from 2019 to late *** reactions are neatly categorized into several types: (A) Catalytic C—H activations,(B) Mizoroki- Heck-type reactions,(C) Suzuki-Miyaura reactions,and (D) Cyclization *** showcasing the potential of water as a sustainable reaction medium for organic transformations,these reactions leave no doubt about the importance of embracing eco-friendly practices in the chemical *** Scientists In 1980,a seminal work by Breslow et *** an acceleration of reaction rate in the Diels-Alder *** and co-workers noted a significant increase in the rate of the [2σ+2σ+2π] cycloaddition of quadricyclane and dimethyl azodicarboxylate (DMAD) when the reaction was conducted in water,as opposed to when it was carried out in organic *** term "on-water" was then coined to describe this *** strategy was further expanded to transition-metal catalyzed transformations by Ackermann in ***,Varma and Leazer disclosed a Pd-catalyzed Mizoroki-Heck type arylation of alkenes with diaryliodonium salts “on-water”.The enantioselective version of "on-water" process was not realized until 2014 by the Zhou *** on,the Schaub group described a Pd-catalyzed Suzuki–Miyaura coupling reaction of electron-poor aryl chlorides with water,using only 50 ppm of catalyst *** recently,Liu and lin extended the "on-water" strategy to Pd-catalyzed double Mizoroki-Heck *** mini-review has focused on Pd-catalyzed reactions involving the “on-water” mechanism.

关键词： Pd-catalyzed “On-water” Green chemistry Aqueous reactions Mechanism Methodology and reactions Mizoroki-Heck reaction Cross-coupling