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Polymer-to-Monomers Chemically Recyclable Poly(imide-imine)Plastics with Extreme-Condition Resistance and Flame Retardancy

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Chinese Journal of Polymer Science 2024年第10期42卷 1525-1535,I0012页

作者： zhen-Yu Wang xiao-Kong Liu State Key Laboratory of Supramolecular Structure and Materials College of ChemistryJilin UniversityChangchun130012China

Polyimides are a family of high-tech plastics that have irreplaceable applications in the fields of aerospace,defense,and opto-electronics,but polyimides are difficult to be reprocessed and recycled at the end of their service life,resulting in a significant waste of ***,it is of great significance to develop recyclable polyimides with comparable properties to the commercial ***,we report a novel polymer-to-monomers chemically recyclable poly(imide-imine)(PtM-CR-PII)plastic,synthesized by cross-linking the amine-terminated aromatic bisimide monomer and the hexa-vanillin terminated cyclophosphazene monomer via dynamic imine *** PtM-CR-PII plastic exhibits comparable mechanical and thermal properties as well as chemical stability to the commercial *** PtM-CR-PII plastic possesses a high Young’s modulus of≈3.2 GPa and a tensile strength as high as≈108 MPa,which also exhibits high thermal stability with a glass transition temperature of≈220℃.Moreover,the PtM-CR-PII plastic exhibits outstanding waterproofness,acid/alkali-resistance,and solvent-resistance,its appearance and mechanical properties can be well maintained after long-term soaking in water,highly concentrated acid and base,and various organic ***,the cyclophosphazene moieties endow the PtM-CR-PII plastic with excellent flame *** PtM-CR-PII plastic exhibits the highest UL-94 flame-retarding rating of V-0 and a limiting oxygen index(LOI)value of 45.5%.Importantly,the PtM-CR-PII plastic can be depolymerized in an organic solvents-acid mixture medium at room temperature,allowing easy separation and recovery of both monomers in high *** recovered pure monomers can be used to regenerate new PtM-CR-PII plastics,enabling sustainable polymer-monomers-polymer circulation.

关键词： Chemical recyclability Polyimides Polyimines Dynamic imine bonds Mechanical properties Chemical stability

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Precise drag prediction of airfoil flows by a new algebraic model

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Acta Mechanica Sinica 2020年第1期36卷 35-43页

作者： Meng-Juan xiao zhen-Su She State Key Laboratory for Turbulence and Complex Systems College of EngineeringPeking UniversityBeijing100871China

We report the results of accurate prediction of lift(C L)and drag(C D)coefficients of two typical airfoil flows(NACA0012 and RAE2822)by a new algebraic turbulence model,in which the eddy viscosity is specified by a stress length(SL)function predicted by structural ensemble dynamics(SED)*** accuracy of the prediction of C D with error of a few counts(one count is 10−4)and of C L with error under 1%-2%are uniformly obtained for varying angles of attack(AoA),indicating an order of magnitude improvement of drag prediction accuracy compared to currently used models(typically around 20 to 30 counts).More interestingly,the SED-SL model is distinguished with fewer parameters of clear physical meaning,which quantify underlying turbulent boundary layer(TBL)with a universal multi-layer structure,and is thus promising to be more easily generalizable to complex *** use of the new model for the calibration of flow condition in experiment and the extraction of flow physics from numerical simulation data of aeronautic flows are discussed.

关键词： Lift and drag coefficients Airfoil Flows Stress Length Structural ensemble dynamics

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Effect of components in activated sludge liquor on membranefouling in a submerged membrane bioreactor

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Journal of Environmental Sciences 2006年第5期18卷 897-902页

作者： YU Shui-li zhao Fang-bo ZHANG xiao-hui JING Guo-lin zhen Xiang-hua School of Municipal and Environmental Engineering Harbin Institute of Technology Harbin 150090 China School of Chemical Engineeering Harbin Engineering University Harbin 150000 China Department of Pathology the Fourth Affiliated Hospital of Harbin Medical University Harbin 150001 China Department of Environmental Engineering Daqing Petroleum Institute Daqing 163000 China

By a membrane bioreactor with a settle tank in long-term operation and batch experiments, the effects of floes, soluble microorganism products （SMPs） and metal ions in activated sludge liquor on membrane fouling were investigated. The results showed that foulants absorbed each other and formed a fouling layer as a ＂second membrane＂ influencing the permeability of the membrane. The ＂gel layer＂ caused by SMPs and ＂cake layer＂ by floes showed great differences in morphology by analysis of scanning electron microscope and atomic force microscope. The ＂gel layer＂ was more compact and of poor permeability. When the membrane flux was 40 L/（m^2·h）, the rate of membrane fouling caused by supernatant （0.011 MPa/h） was greater than that by sludgc liquor （0.0063 MPa/h）. SMPs played very important roles on membrane fouling. In the bulking sludge, with SMPs increasing, the rate of membrane fouling （0.0132 MPa/h） was faster. While after flocculation of the SMPs, the rate of fouling decreased to 0.0034 M Pa/h. Floes could keep holes in their overlaps. They could alleviate membrane fouling by preventing the SMPs directly attaching on membrane surface.

关键词： membrane bioreactor (MBR) membrane fouling soluble microbial products (SMPs) atomic force microscopy (AFM)

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基于H5技术的移动学习在物理实验教学中的应用

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物理实验 2018年第8期38卷 47-50页

作者：白亮高宏马成举李娟妮张小真兆雪西安石油大学物理实验中心陕西西安710065

在物理实验教学过程中,采用H5技术,以手机、平板、电脑为媒介发布课前思考题,提供课堂实验操作步骤,给出课后数据处理指导,完成教学内容的传播.通过应用移动学习平台,可以解决学生学习过程中的问题,实现线上学生和教师之间的交流互动,... 详细信息

在物理实验教学过程中,采用H5技术,以手机、平板、电脑为媒介发布课前思考题,提供课堂实验操作步骤,给出课后数据处理指导,完成教学内容的传播.通过应用移动学习平台,可以解决学生学习过程中的问题,实现线上学生和教师之间的交流互动,还能够采集学生学习过程的数据并进行分析,优化传统课堂教学内容,更新移动教学内容,促进物理实验教学模式改革,提高学生学习效率和课程的教学质量.

关键词： H5技术移动学习物理实验

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A phosphotungstic acid coupled silica-Nafion composite membrane with significantly enhanced ion selectivity for vanadium redox flow battery

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Journal of Energy Chemistry 2020年第2期29卷 177-184页

作者： xiao-Bing Yang Lei zhao Kokswee Goh Xu-Lei Sui Ling-Hui Meng zhen-Bo Wang MIIT Key Laboratory of Critical Materials Technology for New Energy Conversion and Storage School of Chemistry and Chemical EngineeringHarbin Institute of TechnologyHarbin 150001HeilongjiangChina

An ultra-high ion-selective Nafion composite membrane modified by phosphotungstic acid(PWA)coupled silica for vanadium redox flow battery(VRB)was constructed and prepared through solution *** composite membrane exhibits excellent proton conductivity and vanadium ions blocking property by incorporating the nanohybrid composed of silica and PWA into the Nafion *** tuning for the filling amount of the nanohybrid endows the obtained membranes preeminent vanadium barrier property including a minimum vanadium permeability of 3.13×10-7cm2min-1and a maximum proton conductivity of 0.081 S cm-1at 25°*** indicate an ion selectivity of 2.59×105S min cm-3,which is 6.8times higher than that of recast Nafion(0.33×105S min cm-3).As a result,the VRB with the composite membrane shows superior battery performance containing a lower self-discharge rate,higher capacity retention and more robust cyclic stability compared with recast Nafion over a range of current densities from 40 to 100 m A cm-2.

关键词： Vanadium redox flow battery Modified silica Phosphotungstic acid Low vanadium permeability

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Impacts of channel morphology on residues and ecological risks of polychlorinated biphenyls in water and sediment in Chahe River

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Water Science and Engineering 2016年第4期9卷 300-311页

作者： zhen-hua zhao Jie Sun xiao-kun Fang Li-ling Xia Javid Hussain Department of Plant Soil and Microbial Sciences Michigan State University East Lansing MI 48824 USA Key Laboratory of Integrated Regulation and Resource Development on Shallow Lakes of Ministry of Education Hohai University Nanjing 210098 China College of Environment Hohai University Nanjing 210098 China Nanjing Institute of Industry Technology Nanjing 210016 China

The impacts of channel morphology on the residues and ecological risks of 14 polychlorinated biphenyl(PCB) congeners in water and sediment were investigated in summer(July) and autumn(September) in the Chahe River,in Nanjing,*** residual concentrations of trichlorobiphenyls(tri-CBs,PCB 18) and tetra-CBs(PCB 52) in water were significantly higher than those of penta-CBs to deca-CBs,and the average residual concentration of ∑PCBs(sum of 14 PCB congeners) in summer was about six times higher than in ***,the residues in sediment did not change *** analysis(RDA) indicated that channel morphology and the corresponding environmental indices had significant impacts on PCB residues and their composition profiles in water and *** overflow weir and lake-type watercourse may remarkably reduce the residual concentration and ecological risks of PCBs in *** highest reduction percentages of the residual concentration and ecological risks of ∑PCBs induced by an overflow weir were 78%and 67%,respectively,and those induced by a lake-type watercourse were 36%and 70%,*** watercourses with different channel morphologies were ranked by residual ∑PCBs concentrations in the following descending order:the natural ecological watercourse,vertical concrete watercourse,and vegetation-type riprap ***,they were ranked by residual ∑PCBs concentrations in sediment in the following descending order:the vertical concrete watercourse,vegetation-type riprap watercourse,and natural ecological watercourse.

关键词： Channel morphology RDA Ecological risk Toxic equivalent concentration

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习近平文化思想研究的现状、热点与趋势——基于CiteSpace的知识图谱分析

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长江师范学院学报 2025年第1期41卷 14-24页

作者：赵颖彬赵晓营华南师范大学马克思主义学院广东广州510631 中国人民警察大学公安政治学院河北廊坊065000

习近平文化思想是当前学术界研究的热点议题。借助CiteSpace软件,对中国知网2014年1月—2024年4月收录的465篇相关核心期刊文献进行可视化计量分析。结果显示:习近平文化思想研究的相关文献整体呈上升态势,伴随间断性波动与爆发式增长;... 详细信息

习近平文化思想是当前学术界研究的热点议题。借助CiteSpace软件,对中国知网2014年1月—2024年4月收录的465篇相关核心期刊文献进行可视化计量分析。结果显示:习近平文化思想研究的相关文献整体呈上升态势,伴随间断性波动与爆发式增长;研究力量初具规模,研究成果较为丰硕,相关合作呈内部性与近邻性、大分散与小聚集的特点;现有研究较为全面地阐述了习近平文化思想的理论意涵与理论特色、实践意义与实践路径,初步形成以马克思主义为主导、多学科共建的研究格局,但相关研究的理论系统性有待深化、内容创新性有待提升、现实应用性有待强化。未来,要把握理论整体,深化理论体系研究;创新研究内容,推动话语体系研究;聚焦现实应用,强化实践路向研究。

关键词：习近平文化思想热点与趋势 CiteSpace

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Paraneoplastic neurological syndrome with positive anti-Hu and anti-Yo antibodies:A case report

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World Journal of Clinical Cases 2022年第13期10卷 4190-4195页

作者： Zi-Chao Li Hong-Bin Cai zhen-zhen Fan xiao-Bin Zhai zhao-Ming Ge Department of Neurology Lanzhou University Second HospitalLanzhou 730000Gansu ProvinceChina

BACKGROUND Paraneoplastic neurological syndrome(PNS)is a rare complication in patients with *** can affect the central,peripheral,autonomic nervous system,neuromuscular junction,or muscles and cause various neurological ***-Yo antibody-positive neurological paraneoplasms and anti-Hu antibodypositive neurological paraneoplasms are common,but coexistence of both types has not been described in the *** SUMMARY Here we present a rare case of paraneoplastic neuropathy occurring in both breast and lung cancers.A 55-year-old woman was admitted to our hospital with unsteadiness while *** patient had a history of breast cancer two years *** computed tomography revealed a 4.6 cm×3.6 cm mass in the right lung,which was diagnosed as small-cell lung cancer(SCLC).Blood test was positive for anti-Yo antibodies,and the cerebrospinal fluid was positive for both anti-Yo and anti-Hu antibodies,and the neurological symptoms were considered to be related to the *** patient was treated with a course of intravenous immunoglobulin,without noticeable *** being discharged from hospital,the patient underwent regular chemotherapy for SCLC and periodic *** patient’s neurological symptoms continued to deteriorate at the follow-up visit in April *** This case suggests the possibility of two types of tumors appearing simultaneously with two paraneoplastic *** clinical appearance of two or more paraneoplastic tumors requires additional attention.

关键词： Paraneoplastic syndrome Anti-Hu antibody Anti-Yo antibody Small cell lung cancer Breast cancer Intravenous immunoglobulin Case report

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Direct pore engineering of 2D imine covalent organic frameworks via sub-stoichiometric synthesis

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Science China Chemistry 2022年第1期65卷 190-196页

作者： xiao Yang zhen Xie Ting Zhang Guang Zhang Ziqiang zhao Yong Wang Guolong Xing Long Chen Department of Chemistry Tianjin Key Laboratory of Molecular Optoelectronic ScienceTianjin UniversityTianjin 300072China

Two-dimensional covalent organic frameworks(2D COFs)bearing various topologies can be precisely designed based on the symmetry of *** pore environment can be further regulated via either pre-functionalization of the monomers or post-modification of the *** them,sub-stoichiometric synthesis is an efficient method which can mediate uncondensed functional moieties periodically arranged in the COF ***,a series of imine-linked 2D COFs with specifically decorated formyl or amino groups were selectively synthesized via sub-stoichiometric formyl *** molar ratios of the monomers directly determine the structures of the resulting COFs with periodic vertex *** COF with polar amino sites could efficiently capture CO_(2) and H_(2)*** work demonstrates tuning the stoichiometry of the monomers could facilely modulate the functions of the pore *** also provides insights into constructing novel COFs with complex structures for targeted applications.

关键词： covalent organic frameworks sub-stoichiometric periodic vertex vacancies

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Cuticular protein gene LmACP8 is involved in wing morphogenesis in the migratory locust,Locusta migratoria

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Journal of Integrative Agriculture 2021年第6期20卷 1596-1606页

作者： zhao xiao-ming YANG Jia-peng GOU Xin LIU Wei-min ZHANG Jian-zhen Institute of Applied Biology Shanxi UniversityTaiyuan 030006P.R.China College of Life Science Shanxi UniversityTaiyuan 030006P.R.China

Cuticular proteins(CPs)are major components of the insect cuticle-associated organs such as integument and wings,although the importance of CPs for wing development and function in hemimetabolous insects remains *** the present study,a wing cuticular protein LmACP8 was identified from Locusta migratoria,which belongs to the RR-2 subfamily of cuticular protein R&R consensus(CPR)chitin-binding ***8 was mainly expressed in the wing pads and showed high expression levels before ecdysis of third-,fourth-,and fifth-instar nymphs,with its encoded protein located in the procuticle of wing pads and adult *** of LmACP8 by RNA interference markedly reduced the amount of its protein,which consequently caused abnormal wing morphogenesis in the transition from nymph to adult of *** further demonstrated that the abnormal morphogenesis was caused by severe damage of the endocuticle in the ***8 was suppressed by 20-hydroxyecdysone(20 E)in vivo,however,its expression was significantly up-regulated after knocking down the hormone receptor gene ***,the LmACP8 that is negatively regulated by the LmHR39-mediated 20 E signaling pathway is involved in wing development during the nymph to adult transition.

关键词： cuticular proteins LmACP8,20-hydroxyecdysone wing development

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