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史林 2022年第1期 42-50,219-220页

作者：庞煊麒上海师范大学人文学院历史系 200234

明代芦政的演变经历了明初至弘治年间的草创、嘉靖间的进一步改革以及万历以后制度的完善及其异化等三个阶段。芦洲刚开始不为人所重,大多为勋旧占垦、势豪侵占,所谓芦课亦仅被视为杂课之一种。此后随着其面积的扩大及国家财政的紧缩,... 详细信息

明代芦政的演变经历了明初至弘治年间的草创、嘉靖间的进一步改革以及万历以后制度的完善及其异化等三个阶段。芦洲刚开始不为人所重,大多为勋旧占垦、势豪侵占,所谓芦课亦仅被视为杂课之一种。此后随着其面积的扩大及国家财政的紧缩,它越来越受到国家的重视,从专门机构的设立到嘉靖间向一般民众开放占垦,经历了一个重新洗牌的过程,同时朝廷也完善了诸如洲地清丈、芦课征比等方面的则例办法,目的则都是为了更有利于国家赋税的征收,《芦政条例》的成书象征着明代国家层面洲政征管体系的成型。在这一过程中,芦政、芦课也越来越成为国家正项,其管理方式亦向陆上常田税课制度演化。与此同时,"洲头""洲保"等上下其手,聚敛需索等弊端亦接踵而来,成为此后长期困扰洲地社会的"痼疾"。

关键词：明代沙洲芦政芦课洲头

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区传递Steiner t-设计与散在单群

浙江大学学报（理学版） 2024年第3期51卷 265-272页

作者：庞璇詹小秦华东交通大学理学院江西南昌330013

研究具有某种高度对称性的t-设计及其自同构群的分类问题是代数组合学的重要课题之一。目前关于旗传递Steiner t-设计的分类问题已被Huber解决。然而当设计的自同构群的旗传递性减弱为区传递时,研究结果更加丰富,工作也更加困难。利用... 详细信息

研究具有某种高度对称性的t-设计及其自同构群的分类问题是代数组合学的重要课题之一。目前关于旗传递Steiner t-设计的分类问题已被Huber解决。然而当设计的自同构群的旗传递性减弱为区传递时,研究结果更加丰富,工作也更加困难。利用有限单群分类定理及2-传递置换群的分类结果,解决了自同构群为散在单群的区传递Steiner t-设计的分类问题,并证明了:设D=(P,E)为非平凡Steiner t-设计且G≤Aut(D)为点本原群,若G的基柱Soc(G)为散在单群,则G区传递作用在D上当且仅当G旗传递作用在D上,且D为已知的5种旗传递Steiner t-设计之一。

关键词： Steiner t-设计区传递点本原散在单群

选择性催化混合单体制备多组分聚酯的研究进展

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中国科学：化学 2021年第2期51卷 144-153页

作者：周延川庞烜陈学思中国科学院长春应用化学研究所中国科学院生态环境高分子材料重点实验室长春130022

以聚乳酸和聚碳酸酯等为代表的生物可降解高分子材料已被应用于包装材料和生物医用等领域.然而受链段结构的影响,这类均聚物材料在实际应用中受到了一定限制.将不同性质聚合物链段通过共价键连接形成的嵌段共聚物具有组分均匀、性能可... 详细信息

以聚乳酸和聚碳酸酯等为代表的生物可降解高分子材料已被应用于包装材料和生物医用等领域.然而受链段结构的影响,这类均聚物材料在实际应用中受到了一定限制.将不同性质聚合物链段通过共价键连接形成的嵌段共聚物具有组分均匀、性能可控等优点,是优化材料性能的一种方法.本文概述了环酯、环氧化物和CO_(2)(或环状酸酐)的多元共聚反应合成嵌段聚酯的研究进展.首先介绍了多元共聚反应中链增长机理和判断嵌段共聚物结构的表征方法,进一步讨论了催化体系-聚合物结构的关系和聚合物材料的性能表征.

关键词：选择性催化开环聚合反应聚酯多元共聚物

New sustainable polymers with on-demand depolymerization property

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Science China Chemistry 2024年第9期67卷 2803-2841页

作者： Yangyang Sun Zesheng An Yanshan Gao Rongrong Hu Ye Liu Hua Lu Xiao-Bing Lu xuan pang Anjun Qin Yong Shen Youhua Tao Yu-Zhong Wang Junpeng Wang Gang Wu Guang-Peng Wu Tie-Qi Xu Xing-Hong Zhang Yuetao Zhang Zhenbiao Zhang Jian-Bo Zhu Miao Hong Zhibo Li State Key Laboratory of Organometallic Chemistry Shanghai Institute of Organic ChemistryChinese Academy of SciencesShanghai 200032China State Key Laboratory Base of Eco-Chemical Engineering College of Chemical EngineeringQingdao University of Science and TechnologyQingdao266042China State Key Laboratory of Supramolecular Structure and Materials College of ChemistryJilin UniversityChangchun 130012China State Key Laboratory of Luminescent Materials and Devices Guangdong Provincial Key Laboratory of Luminescence from Molecular AggregatesSouth China University of TechnologyGuangzhou 510640China State Key Laboratory of Fine Chemicals Frontiers Science Center for Smart MaterialsDalian University of TechnologyDalian 116024China Beijing National Laboratory for Molecular Sciences Center for Soft Matter Science and EngineeringKey Laboratory of Polymer Chemistry and Physics of Ministry of EducationCollege of Chemistry and Molecular EngineeringPeking UniversityBeijing 100871China Key Laboratory of Polymer Ecomaterials Changchun Institute of Applied ChemistryChinese Academy of SciencesChangchun 130022China The Collaborative Innovation Center for Eco-Friendly and Fire-Safety Polymeric Materials(MoE) National Engineering Laboratory of Eco-Friendly Polymeric Materials(Sichuan)College of ChemistryState Key Laboratory of Polymer Materials EngineeringSichuan UniversityChengdu 610064China School of Polymer Science and Polymer Engineering the University of AkronAkronOH 44325USA MOE Key Laboratory of Macromolecular Synthesis and Functionalization Department of Polymer Science and EngineeringZhejiang UniversityHangzhou 310027China State and Local Joint Engineering Laboratory for Novel Functional Polymeric Materials Jiangsu Key Laboratory of Advanced Functional Polymer Design and ApplicationSuzhou Key Laboratory of Macromolecular Design and Precision SynthesisCollege of ChemistryChemical Engineering and Materials ScienceSoochow UniversitySuzhou 215123China

To combat the crisis of today's synthetic polymers arising from unsustainable production and disposal,it is essential for the synthetic polymer community to reshape the current polymer industry with sustainable *** an emerging class of sustainable polymers,the development of chemically depolymerizable polymers(CDPs),which can undergo closed-loop depolymerization/repolymerization cycles to reproduce virgin polymers without the loss of properties from recovered monomers,offers an ideal solution to preserve finite natural resources,provides a feasible solution to the end-of-life issue of polymer waste,and thereby establishes a circular materials ***,two grand key challenges have been encountered in the establishment of practically useful CDPs:how to balance polymerization and depolymerization ability and how to unify conflicted depolymerizability and physical ***,this critical review article presents our vision for summarizing feasible strategies to overcome the above two significant challenges and the design principles for constructing an ideal CDP by highlighting selected major progress made in this rapidly expanding field.

关键词： chemically depolymerizable polymers sustainable polymers depolymerization monomer recovery degradation plastics

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浅谈聚羧酸系减水剂的复配改性

福建建设科技 2008年第6期 67-68页

作者：潘轩福建省建筑科学研究院建材研究所350025

为了探讨聚羧酸系减水剂的复配改性,本文选择葡萄糖酸钠、消泡剂与聚羧酸系减水剂进行复配。采用相同配合比,在葡萄糖酸钠、消泡剂不同掺量情况下进行混凝土性能试验。研究结果表明:对聚羧酸系减水剂进行复配可优化混凝土的性能,但存在... 详细信息

为了探讨聚羧酸系减水剂的复配改性,本文选择葡萄糖酸钠、消泡剂与聚羧酸系减水剂进行复配。采用相同配合比,在葡萄糖酸钠、消泡剂不同掺量情况下进行混凝土性能试验。研究结果表明:对聚羧酸系减水剂进行复配可优化混凝土的性能,但存在一个最佳掺量。

关键词：聚羧酸系减水剂复配混凝土性能试验

席夫碱-铝配合物的合成及对丙交酯的立体选择性聚合

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高等学校化学学报 2014年第3期35卷 626-632页

作者：曲智李想庞烜段然龙高波陈学思中国科学院长春应用化学研究所生态环境高分子材料重点实验室长春130022 中国科学院大学北京100049

设计、合成了一系列不对称席夫碱配体,得到了相应的金属铝配合物.研究了配合物在外消旋丙交酯的开环聚合反应中的催化性能.结果表明,系列配合物对外消旋丙交酯(rac-LA)的聚合催化活性明显提高,并具有立体选择性.

关键词：丙交酯生物降解立体选择性聚合席夫碱

Three-dimensional fracture of UO2 ceramic pellets by phase field modeling

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Science China(Physics,Mechanics & Astronomy) 2025年第1期Mechanics & Astronomy) .卷 169-180页

作者： Wei Xiong xuan Ye Hongzhang Cheng Xiaoming Liu Institute of Nuclear and New Energy Technology Collaborative Innovation Center of Advanced Nuclear Energy Technology Key Laboratory of Advanced Reactor Engineering and Safety of Ministry of Education Tsinghua University State Key Laboratory of Nonlinear Mechanics Institute of Mechanics Chinese Academy of Sciences School of Engineering Science University of Chinese Academy of Sciences

Fracture is the primary failure type for the UO2ceramic pellets,which are operated under irradiation and thermal processes,and physically confined by the *** this work,by combining closely coupled physical processes of heat conduction,heat transfer,and mechanical deformation with the cohesive phase field framework,we proposed a high-precision modeling of quasistatic cracking of three-dimensional （3D） UO2ceramic fuel pellets under high temperature and *** simulation results agree well with the experimental results,indicating that the proposed method has the potential to capture 3D crack modes in the interested time ***,we studied the relation of the 3D fracture patterns of fuel pellets with the peak power *** was found that the power level plays a critical role in determining the competition between radial and circumferential cracks,as well as transverse penetrating cracks.

关键词： phase field method nuclear fuel pellet coupled thermo-mechanical model thermal fracture

Emerging progress: photochemical transformation of nitroso compounds

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Science China Chemistry 2025年第1期68卷 118-133页

作者： Ze-Le Chen Qiang-Qiang Li Armido Studer Jun xuan Anhui Province Key Laboratory of Chemistry for Inorganic/Organic Hybrid Functionalized Materials School of Chemistry & Chemical Engineering Anhui University Organisch-Chemisches Institut Universitat Münster

Nitroso compounds have emerged as highly valuable reaction partners or reagents in organic synthesis due to their rich *** versatile profile of these compounds allows them to function as electrophiles, nucleophiles, diradicals, and radical acceptors in diverse transformations. In recent years, notable progress has been made in harnessing photochemical reactions with nitroso compounds to prepare N,O-containing structures using mild and eco-friendly conditions. Various nitroso compounds like nitrosoarenes, acyloxy nitroso compounds, N-nitrosoamines and nitrites have received significant attention for their ability to introduce NO moieties into complex molecules that are otherwise difficult to access. In this review, we provide an overview of the recent advancements in the visible light-induced conversion of nitroso compounds, with particular emphasis on their role as bifunctional reagents and acceptors of radicals, carbenes and nitrenes.

关键词： nitroso compounds photochemistry radical reaction carbene transformation nitrosoarenes

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席夫碱-铝化合物催化己内酯的开环聚合

高等学校化学学报 2014年第4期35卷 869-872页

作者：曲智李想庞烜段然龙高波陈学思中国科学院长春应用化学研究所生态环境高分子材料重点实验室长春130022 中国科学院大学北京100049

设计合成了一系列不对称席夫碱-铝化合物1a^3a,考察了化合物在己内酯(CL)开环聚合反应中的催化性能,研究发现,配合物对CL聚合具有较高的反应活性,并具有活性聚合的特点,聚合反应均符合一级动力学反应特征.在其它条件相同时,吸电子取代... 详细信息

设计合成了一系列不对称席夫碱-铝化合物1a^3a,考察了化合物在己内酯(CL)开环聚合反应中的催化性能,研究发现,配合物对CL聚合具有较高的反应活性,并具有活性聚合的特点,聚合反应均符合一级动力学反应特征.在其它条件相同时,吸电子取代的配合物的催化速率约为无吸电子的配合物的4倍,表明席夫碱配体上吸电子基团的存在可以提高配合物催化聚合的活性.

关键词：着-己内酯开环聚合席夫碱-铝配合物催化剂