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Protein adsorption on the poly(L-lactic acid) surface modified by chitosan and its derivatives

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Chinese Science Bulletin 2009年第18期54卷 3167-3173页

作者： JIAO YanPeng ZHOU ChangRen LI LiHua ding shan lu lu luO BingHong LI Hong Department of Materials Science and Engineering Jinan University Guangzhou China 510632

Surface modification of biomaterials has been adopted over the years to improve their biocompatibility. In this study, aiming to promote hydrophilicity and to introduce natural recognition sites onto poly(L-lactic acid) (PLLA) films, chitosan and its derivatives, carboxymethyl chitosan(CMC) and N-methylene phosphonic chitosan (NPC), were used to modify the surface of PLLA films by an entrapment method. Radiolabeled (125I) proteins were used to measure the amount of protein adsorbed to PLLA surfaces. Fibronectin (Fn) was used to study the protein adsorption on the modified PLLA surfaces, including isotherm adsorption and adsorption kinetics of single protein, competitive adsorption of binary proteins system and serum multi-proteins and the desorption behavior in serum solution. The results showed that in the isotherm adsorption, Fn had a larger adsorption capacity on the CS-modified surface at lower concentrations, but had a high adsorption capacity at CMC-modified surface at higher concentrations. In the study of absorption kinetics, Fn had a fastest adsorption equilibrium and a highest equilibrium adsorption capacity at the CS-modified surface, while it was opposite at the PCS-modified surface. When BSA and serum were added, it had the greatest effect on the adsorption of Fn on the PCS-modified surface. After 6 hours soaking in the desorption study, Fn had reached desorption equilibrium on all the modified surfaces, which had different effects on the desorption rate and the remaining percentage of Fn.

关键词：材料表面改性蛋白质吸附改性壳聚糖聚乳酸衍生物羧甲基壳聚糖 125I标记纤维连接蛋白

Influence of carbon content on wear resistance and wear mechanism of Mn13Cr2 and Mn18Cr2 cast steels

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China Foundry 2015年第1期12卷 39-47页

作者： ding-shan lu Zhong-yi Liu Wei Li Zhao Liao Hui Tian Jian-zhong Xian Department of Materials Science and Engineering Jinan University Engineering Research Center of Wear Resistant Materials Jinan University Guangxi Great Wall Mining Machinery Equipment Manufacturing Company

By means of impact abrasion tests, micro-hardness tests, and worn surface morphology observation via SEM, a comparison research based upon different impact abrasive wear conditions was conducted in this research to study the influence of different carbon contents(1.25 wt.%, 1.35 wt.%, and 1.45 wt.%) on the wear resistance and wear mechanism of water-quenched Mn13Cr2 and Mn18Cr2 cast steels. The research results show that the wear resistance of the Mn18Cr2 cast steel is superior to that of the Mn13Cr2 cast steel under the condition of the same carbon content and different impact abrasive wear conditions because the Mn18Cr2 cast steel possesses higher worn work hardening capacity as well as a more desirable combination of high hardness and impact toughness than that of the Mn13Cr2 cast steel. When a 4.5 J impact abrasive load is applied, the wear mechanism of both steels is that plastic deformation fatigue spalling and micro-cutting coexist, and the former dominates. When the carbon content is increased, the worn work hardening effect becomes increasingly dramatic, while the wear resistance of both steels decreases, which implies that an increase in impact toughness is beneficial to improving the wear resistance under severe impact abrasive wear conditions. Under the condition of a 1.0 J impact abrasive load, the wear mechanism of both steels is that plastic deformation fatigue spalling and micro-cutting coexist, and the latter plays a leading role. The worn work hardening effect and wear resistance intensify when the carbon content is increased, which implies that a higher hardness can be conducive to better wear resistance under low impact abrasive condition.

关键词： high manganese steel carbon content water-quenched hardness-toughness combination wear-resistance wear mechanism

Weighted Boundedness for a Class of Rough Multilinear Operators

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Acta Mathematica Sinica,English Series 2001年第3期17卷 517-526页

作者： Yong ding shan Zhen lu Department of Mathematics,Beijing Normal University,Beijing 100875,P.R.China E-mail:dingy@*** lusz@*** Department of Mathematics Beijing Normal University Beijing 100875 P. R. China

In this paper we give the (L^p(ω~p),L^q(ω~q)) boundedness for a class of multilinear operators, which is similar to the higher-order commutator for the rough fractional *** our results the kernel function is merely ... 详细信息

关键词： Multilinear operator Fractional integral Rough kernel BMO A(p,q) weight

Continuity of Higher Order Commutators on Certain Hardy Spaces

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Acta Mathematica Sinica,English Series 2002年第2期18卷 391-404页

作者： ding Yong lu shan Zhen Department of Mathematics,Beijing Normal University,Beijing 100875.P.R.China E-mail:dingy@*** lusz@***ZHANG Pu Department of Mathematics.Zhejiang University(at Xixi Campus).Hangzhou 310028,P.R.China,E-mail:zhpjj@263,net Department of Mathematics Beijing Normal University Beijing P.R. China Department of Mathematics Zhejiang University (at Xixi Campus) Hangzhou P.R. China

In this *** authors study the continuity properties of higher order commutators generated by the homogeneous fractional integral and BMO functions on certain Hardy spaces,weak Hardy spaces and Herz-type Hardy spaces.

关键词： Fractional integral Homogeneous kernel L^r-Dini condition Hardy space Herz-type Hardy space

氧化时间对内燃机用IN718合金在300℃蒸气中氧化层组织的影响

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材料保护 2020年第9期53卷 56-59,69页

作者：朱镜瑾张勇丁录善黄河交通学院汽车工程学院河南焦作454950 海马汽车有限公司河南焦作454950

为了提高对内燃机用IN718合金表面抗氧化机理的认识,通过试验测试的手段研究了氧化时间对合金在300℃蒸气中氧化层组织的影响。结果表明:当氧化时间增加后,试样的重量也不断提高。2160 h氧化后合金依然形成γ基体与(Fe0.6Cr0.4)2O3衍射... 详细信息

为了提高对内燃机用IN718合金表面抗氧化机理的认识,通过试验测试的手段研究了氧化时间对合金在300℃蒸气中氧化层组织的影响。结果表明:当氧化时间增加后,试样的重量也不断提高。2160 h氧化后合金依然形成γ基体与(Fe0.6Cr0.4)2O3衍射峰,(Fe0.6Cr0.4)2O3衍射峰明显增强。当氧化时间达到96 h时,试样表面生成具有完整组织结构的氧化层;当氧化时间到达1440 h时,试样表面生成了相连胞状(Fe0.6Cr0.4)2O3;经过2160 h氧化后试样表面产生具有连续结构的胞状氧化层,在外氧化层中含有较高的Cr。随着氧化时间的增加,氧化层的厚度明显增加。2160 h氧化后合金形成约1.8μm外氧化层,同时内氧化层的深度提高至2.3μm,内氧化层具备更快的生长速率。在外氧化层中也含有较高比例的Cr,Ti含量很低,Al元素聚集于外氧化层和基体的交界区域以及内氧化层中。

关键词： IN718合金蒸汽氧化氧化时间微观组织

From waste to wealth:Coal tar residue derived carbon materials as low-cost anodes for potassium-ion batteries

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International Journal of Minerals,Metallurgy and Materials 2025年第2期32卷 464-475页

作者： Zhonghua lu Jun Shen Xin Zhang Lingcong Chao Liang Chen ding Zhang Tao Wei Shoudong Xu College of Chemical Engineering and Technology Taiyuan University of TechnologyTaiyuan 030024China College of Chemistry Taiyuan University of TechnologyTaiyuan 030024China School of Chemical Engineering and Pharmacy Wuhan Institute of TechnologyWuhan 430205China School of Energy and Power Jiangsu University of Science and TechnologyZhenjiang 212003China

Carbon materials are widely recognized as highly promising electrode materials for various energy storage system *** tar residues(CTR),as a type of carbon-rich solid waste with high value-added utilization,are crucially important for the development of a more sustainable *** this study,we employed a straightforward direct carbonization method within the temperature range of 700-1000℃to convert the worthless solid waste CTR into economically valuable carbon materials as anodes for potassium-ion batteries(PIBs).The effect of carbonization temperature on the microstructure and the potassium ions storage properties of CTR-derived carbons(CTRCs)were systematically explored by structural and morphological characterization,alongside electrochemical performances *** on the co-regulation between the turbine layers,crystal structure,pore structure,functional groups,and electrical conductivity of CTR-derived carbon carbonized at 900℃(CTRC-900H),the electrode material with high reversible capacity of 265.6m Ah·g^(-1)at 50 m A·g^(-1),a desirable cycling stability with 93.8%capacity retention even after 100 cycles,and the remarkable rate performance for PIBs were ***,cyclic voltammetry(CV)at different scan rates and galvanostatic intermittent titration technique(GITT)have been employed to explore the potassium ions storage mechanism and electrochemical kinetics of *** indicate that the electrode behavior is predominantly governed by surface-induced capacitive processes,particularly under high current densities,with the potassium storage mechanism characterized by an“adsorption-weak intercalation”*** work highlights the potential of CTR-based carbon as a promising electrode material category suitable for high-performance PIBs electrodes,while also provides valuable insights into the new avenues for the high value-added utilization of CTR.

关键词： coal tar residue carbon materials anode potassium-ion batteries high value-added

Staged dendrite suppression for high safe and stable lithium-sulfur batteries

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Journal of Energy Chemistry 2025年第1期100卷 674-683页

作者： Jun Jiang Zhenjie lu Yanwen ding Shujun Liu Zhijie Qi Tian Tang Yunfan Zhang Zhiyuan Ma Jingwen Sun Liang Xue Wenyao Zhang Pan Xiong Xin Wang Junwu Zhu Yongsheng Fu Key Laboratory for Soft Chemistry and Functional Materials of Ministry of Education Nanjing University of Science and Technology Jiangsu Pylon Battery Co.Ltd

The unavoidable dendrite growth and shuttle effect have long been stranglehold challenges limiting the safety and practicality of lithium-sulfur ***,we propose a dual-action strategy to address the lithium dendrite issue in stages by constructing a multifunctional surface-negatively-charged nanodiamond layer with high ductility and robust puncture resistance on polypropylene （PP） *** uniformly loaded compact negative layer can not only significantly enhance electron transmission efficiency and promote uniform lithium deposition,but also reduce the formation of dendrite during early deposition *** importantly,under the strong puncture stress encountered during the deterioration of lithium dendrite growth under limiting current,the high ductility and robust puncture resistance（145.88 MPa） of as-obtained nanodiamond layer can effectively prevent short circuits caused by unavoidable lithium *** Li||Li symmetrical cells assembled with nanodiamond layer modified PP demonstrated a stable cycle of over 1000 h at 2 mA cm-2with a polarization voltage of only 29.3 ***,the negative charged layer serves as a physical barrier blocking lithium polysulfide ions,effectively mitigating capacity *** improved cells achieved a capacity decay of only 0.042%per cycle after 700 cycles at 3 C,demonstrating effective suppression of dendrite growth and capacity attenuation,showing promising prospect.

关键词： Lithium-sulfur batteries Staged dendrite suppression Shuttle effect Surface-negatively-charged nanodiamond

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高阶交换子在Hardy空间上的连续性

数学学报（中文版） 2005年第1期48卷 191-200页

作者：丁勇陆善镇张璞北京师范大学数学系北京100875 浙江工程学院信息与计算科学系杭州310018

本文研究了由齐性分数次积分和BMO函数生成的高阶交换子在某些Hardy空间、弱Hardy空间和Herz型Hardy空间上的连续性.

关键词： Herz型Hardy空间高阶交换子连续性分数次积分 BMO函数弱Hardy空间生成

新时代大学生爱国主义教育的现实境遇与实践理路——基于《爱国主义教育法》实施视角

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高校辅导员学刊 2025年第1期17卷 15-19,95,96页

作者：丁露江西陶瓷工艺美术职业技术学院马克思主义学院江西景德镇333300

在“两个大局”背景下,西方强势的意识形态输出、国家经济社会发展的新矛盾新问题、碎片化和去中心化的“信息茧房”给新时代大学生爱国主义教育带来严峻挑战。《中华人民共和国爱国主义教育法》应运而生,为新时代大学生爱国主义教育的... 详细信息

在“两个大局”背景下,西方强势的意识形态输出、国家经济社会发展的新矛盾新问题、碎片化和去中心化的“信息茧房”给新时代大学生爱国主义教育带来严峻挑战。《中华人民共和国爱国主义教育法》应运而生,为新时代大学生爱国主义教育的现实境遇提供了规范——“教什么”、创新——“怎么教”、落实——“谁来教”的价值指向,同时通过尊法、学法、守法、用法、执法、护法的“六维”方式找到了涵养大学生爱国主义教育法治思维、规范大学生爱国主义教育法治行动、保障大学生爱国主义教育运行的实践理路。

关键词：《中华人民共和国爱国主义教育法》大学生爱国主义教育现实境遇实践理路