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Molecular Weight Dependence of Associative Behavior in Polyimide/DMF Solutions

Chinese Journal of Polymer Science 2020年第6期38卷 629-637页

作者： Hong-Xiang Chen en-song zhang Mei Hong Wei Liu Xue-Min Dai Quan Chen Xue-Peng Qiu Xiang-Ling Ji State Key Laboratory of Polymer Physics and Chemistry Changchun Institute of Applied ChemistryChinese Academy of SciencesChangchun 130022China School of Applied Chemistry and engineering University of Science and Technology of ChinaHefei230026China Laboratory of Polymer Composites and engineering Changchun Institute of Applied ChemistryChinese Academy of SciencesChangchun 130022China

Eight 6FDA-TFDB polyimide(PI)samples with absolute molecular weights ranging from 1.25 × 10^5 g mol^-1 to 3.11 × 10^5 g mol^-1 are obtained by precipitation *** experiments are conducted to determine the influence of molecular weight on the associating behavior of PI in A/X-dimethylformamide(DMF)solutions in a broad volume fraction,including abnormal steady shear flow,solution heterogeneity,and scaling *** flow behaviors,i.e.,multi-region shear thinning and weak shear thickening,are studied,and these behaviors have not been reported in *** heterogeneity of PI/DMF solutions is examined by dynamic rheological *** plotting qsp versus four concentration regions of l-IV can be distinguished for all PI samples with various molecular *** scaling results in different concentration regions are in good agreement with the associative polymer theory proposed by Rubinstein and *** scaling exponents do not show molecular weight dependence in concentration regions I and *** concentration regions Ⅲ and Ⅳ,the scaling exponents change little when the molecular weight is below 242 k but increase when the molecular weight increases from 242 k to 311 *** work can help us to understand polyimide solution properties from dilute to semidilute entangled solutions,and will guide the polyimide solution preparation for different processing.

关键词： Soluble polyimide Molecular weight Rheology Associative polymer Scaling behavior

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Comparison of Different Methods for Determining the Imidization Degree of Polyimide Fibers

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Chinese Journal of Polymer Science 2016年第2期34卷 209-220页

作者： Wen-ke Yang Fang-fang Liu Guo-min Li en-song zhang Yan-hu Xue Zhi-xin Dong 邱雪鹏姬相玲 State Key Laboratory of Polymer Physics and Chemistry Changchun Institute of Applied Chemistry Chinese Academy of Sciences University of Chinese Academy of Sciences Laboratory of Polymer Composites and engineering Changchun Institute of Applied Chemistry Chinese Academy of Sciences

In this study, polyimide fibers at different stages of imidization were characterized by TGA, DSC, and FTIR. The imidization degree （ID） calculated by TGA was based on the weight loss of each sample, which was caused by the imidization of residual amic acid groups. The results of TGA showed good regularity with the thermal treatment temperature of the PI fibers. For DSC, the ID was calculated based on the area of endothermal peak of each sample. Compared with TGA, DSC showed a relatively higher value because the endothermal peak was reduced by the exothermic re-formation of polyamic acid which may be partially degraded during thermal treatment. The IDs obtained by the FTIR spectra generally showed poorer regularities than those obtained by both TGA and DSC, especially for the results calculated using the 730 cm^-1 band. Based on the 1350 cm^-1 band, the obtained IDs showed better agreement with the TGA or DSC results. The results obtained by these three methods were compared and analyzed. The ID obtained by TGA showed much more reliability among these three methods.

关键词： Imidization degree Polyimide fibers Polyamic acid Polyimide Characterization.

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金属卟啉二维纳米晶的制备及其光电性能

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物理化学学报 2016年第10期32卷 2447-2461页

作者：石乃恩宋传远张俊黄维南京邮电大学信息材料与纳米技术研究院江苏省有机电子与信息显示重点实验室南京210023 南京工业大学先进材料研究院江苏-新加坡有机/生物电子与信息显示联合研究中心南京211816

金属卟啉是一种重要的金属-有机复合物,在光电转换器件、催化、传感、医学等领域有着广阔的应用前景。对无机二维纳米材料(石墨烯或过渡金属硫属化合物等)的广泛研究促使金属-有机二维纳米材料成为当前的研究热点之一。本文针对金属-有... 详细信息

金属卟啉是一种重要的金属-有机复合物,在光电转换器件、催化、传感、医学等领域有着广阔的应用前景。对无机二维纳米材料(石墨烯或过渡金属硫属化合物等)的广泛研究促使金属-有机二维纳米材料成为当前的研究热点之一。本文针对金属-有机以及卟啉二维纳米材料的研究现状,在简要回顾金属-有机二维纳米材料发展历史的基础上,详细总结了金属卟啉单分散二维纳米晶和二维薄膜的制备方法,综述了其当前在太阳能电池、光电催化以及光学传感等方面的应用,最后讨论了金属卟啉二维纳米材料当前面临的研究问题及未来可能的发展方向。

关键词：卟啉二维材料纳米片纳米薄膜光电性质

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Synergistically enhanced ORR and HER performance on Co-N-C coupled in-situ generated PtCo intermetallic

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Journal of energy Chemistry 2025年第1期100卷 721-729页

作者： Guanyu Luo Min song Lulu An Xiao Huang Qian zhang Chenhao zhang Tao Shen Shuang Wang Deli Wang Key Laboratory of Material Chemistry for energy Conversion and Storage (Huazhong University of Science and Technology) Ministry of Education School of Chemistry and Chemical Engineering Huazhong University of Science and Technology

Integrating multi-scale sites in a composite catalyst is vital to realize efficient ***,a synergistic composite catalyst consisting of Co atomic sites and in-situ generated PtCo intermetallic compounds （IMCs）(o-PtCo@CoNC) is proposed through Co pre-anchoring and subsequent impregnation-reduction *** loading of Co atoms provides a chance for in-situ generating PtCo ordered intermetallic *** remaining Co single atoms and PtCo IMCs construct synergistic electrocatalytic *** from the ordered structure,synergistic effect of Pt Co IMCs and Co single atoms,o-PtCo@CoNC exhibits excellent electrocatalytic performance for oxygen reduction reaction （ORR） and hydrogen evolution reaction （HER） with mass activity of 1.21 A mgPt-1（at 0.9 V） and5.70 A mgPt-1（at an overpotential of 100 mV）,***,o-PtCo@CoNC delivers negligible loss of half-wave potential and overpotential during long-term stability test in acid solutions,with 13 mV decay after 50,000 potential cycles for ORR and a 2.7 mV decay after 20,000 potential cycles for *** integration strategy of single-atomic sites coupled IMCs paves the way for enhancing the activity and durability of Pt-based electrocatalysts.

关键词： Electrolytic reduction

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采用流变学方法研究聚酰胺酸6FDA-TFDB溶液的降解行为

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高分子学报 2017年第9期27卷 1497-1505页

作者：张恩菘代学民刘学杨文轲刘巍董志鑫邱雪鹏姬相玲中国科学院长春应用化学研究所高分子物理与化学国家重点实验室中国科学院大学北京100049 高分子复合材料工程实验室长春130022

合成了一种聚酰胺酸6FDA-TFDB溶液,利用流变仪研究其在不同影响因素(如:温度、升温速率、溶剂含水量等)下的流变行为,发现聚酰胺酸溶液的降解在高温区和低温区存在不同的行为.通过Andrade公式获得不同条件下聚酰胺酸溶液的黏流活化能,... 详细信息

合成了一种聚酰胺酸6FDA-TFDB溶液,利用流变仪研究其在不同影响因素(如:温度、升温速率、溶剂含水量等)下的流变行为,发现聚酰胺酸溶液的降解在高温区和低温区存在不同的行为.通过Andrade公式获得不同条件下聚酰胺酸溶液的黏流活化能,并比较其差异,同时对溶剂水含量在不同温度区域下对聚酰胺酸降解速率的影响也进行了深入的分析,从而建立一种半定量比较不同条件下聚酰胺酸溶液降解速率的方法.

关键词：聚酰胺酸降解行为流变仪黏度黏流活化能

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Universal design of three-dimensional porous graphene-iron based promotors for kinetically rationalized lithium-sulfur chemistry

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Journal of energy Chemistry 2025年第1期100卷 192-200页

作者： Hua Gao Yunfeng zhang Menglei Wang Ruoxuan Yang Shuai Feng Xuan Cao Yaping zhang Zhongyuan Lu Yingze song State Key Laboratory of environment-Friendly energy Materials School of Materials and Chemistry Southwest University of Science and Technology School of Material Science and engineering Henan University of Technology College of Chemistry and Chemical engineering Taishan University

Lithium-sulfur （Li-S） batteries are widely deemed to be one of the most potential candidates for future secondary batteries because of their remarkable energy ***,notorious polysulfide shuttling and retarded sulfur reaction kinetics pose significant obstacles to the further application of Li-S *** rationally designed highly active electrocatalysts can facilitate polysulfide conversion,the universal and scalable synthesis strategies need to be ***,a universal synthetic strategy to construct a series of three-dimensional （3D） porous graphene-iron （3DGr-Fe） based electrocatalysts involving 3DGr-FeP,3DGr-Fe3C,and 3DGr-Fe3Se4is exploited for manipulating the Li-S redox *** has been observed that the implementation of a 3D porous Gr architecture leads to the well-designed conductive networks,while the uniformly dispersed iron nanoparticles introduce an abundance of active sites,fostering the lithium polysulfide conversion,thereby bolstering the overall electrochemical *** Li-S battery with the 3DGr-Fe based electrocatalyst exhibits remarkable capacity retention of 94.8%upon 100 times at 0.2 ***,the soft-packaged Li-S pouch cell based on such a 3DGr-Fe electrocatalyst delivers superior capacity of 1060.71 mA h g-1and guarantees for the continuous 30 min work of fan *** investigation gives comprehensive insights into the design,synthesis,and mechanism of 3DGr-Fe based electrocatalysts with high activity toward efficient and durable Li-S batteries.

关键词： Lithium-sulfur battery Universal synthesis 3D graphene-iron based promotor Electrocatalysis

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Carbon-supported CenCl as an efficient catalyst for CO_(2)cycloaddition

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Nano Research 2025年第1期18卷 157-163页

作者： Li Liu Lingling zhang Xiang Chu Baokang Geng Huilin Wang Zongxiang Li Xiao Wang Shuyan song Hongjie zhang School of Applied Chemistry and engineering University of Science and Technology of ChinaHefei 230026China State Key Laboratory of Rare Earth Resource Utilization Changchun Institute of Applied ChemistryChinese Academy of SciencesChangchun 130022China Sinocare Incorporation Changsha 410221China Department of Chemistry Tsinghua UniversityBeijing 100084China

The cycloaddition reaction of CO_(2)with epoxide not only effectively reduces the concentration of CO_(2)in the atmosphere,but also has excellent industrial application value and up to 100%atom utilization,but there are difficulties in separation and recovery of traditional homogeneous catalysts,harsh reaction conditions of traditional heterogeneous catalysts,and activation of CO_(2)*** this paper,an easily synthesized heterogeneous catalyst CenCl/C was used to catalyze the cycloaddition reaction of CO_(2)with styrene oxide,with a high yield of 92.7%,a high selectivity of 96.7%,a turnover numbers(TON)value of 349,and a good stability demonstrated in six cycle tests(equivalent to 216 h of testing).Through comprehensive studies,it was shown that CenCl/C contains Lewis acid-base centers as active centers,which can effectively reduce the energy barrier required for ring opening of the reaction substrate,enhance the adsorption and activation of CO_(2),and promote the formation of intermediates,which led to the acquisition of excellent catalytic activity.

关键词： CO_(2)cycloaddition heterogeneous catalysis CenCl Lewis acid/base

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MoS_(2)Lubricate‑Toughened MXene/ANF Composites for Multifunctional Electromagnetic Interference Shielding

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Nano-Micro Letters 2025年第2期17卷 358-371页

作者： Jiaen Wang Wei Ming Longfu Chen Tianliang song Moxi Yele Hao zhang Long Yang Gegen Sarula Benliang Liang Luting Yan Guangsheng Wang School of Physical Science and engineering Beijing Jiaotong UniversityBeijing 100044People’s Republic of China Key Laboratory of Bio‑Inspired Smart Interfacial Science and Technology of Ministry of Education School of ChemistryBeihang UniversityBeijing 100191People’s Republic of China

The design and fabrication of high toughness electromagnetic interference(EMI)shielding composite films with diminished reflection are an imperative task to solve electromagnetic pollution *** MXene/ANF(aramid nanofibers)–MoS_(2)composite films with nacre-like layered structure here are fabricated after the introduction of MoS_(2)into binary MXene/ANF composite *** introduction of MoS_(2)fulfills an impressive“kill three birds with one stone”improvement effect:lubrication toughening mechanical performance,reduction in secondary reflection pollution of electromagnetic wave,and improvement in the performance of photothermal *** the introduction of MoS_(2)into binary MXene/ANF(mass ratio of 50:50),the strain to failure and tensile strength increase from 22.1±1.7%and 105.7±6.4 MPa and to 25.8±0.7%and 167.3±9.1 MPa,*** toughness elevates from 13.0±4.1 to 26.3±0.8 MJ m^(−3)(~102.3%)*** the reflection shielding effectiveness(SE_(R))of MXene/ANF(mass ratio of 50:50)decreases~10.8%.EMI shielding effectiveness(EMI SE)elevates to 41.0 dB(8.2–12.4 GHz);After the introduction of MoS_(2)into binary MXene/ANF(mass ratio of 60:40),the strain to failure increases from 18.3±1.9%to 28.1±0.7%(~53.5%),the SE_(R)decreases~22.2%,and the corresponding EMI SE is 43.9 *** MoS_(2)also leads to a more efficient photothermal conversion performance(~45 to~55℃).Additionally,MXene/ANF–MoS_(2)composite films exhibit excellent electric heating performance,quick temperature elevation(15 s),excellent cycle stability(2,2.5,and 3 V),and long-term stability(2520 s).Combining with excellent mechanical performance with high MXene content,electric heating performance,and photothermal conversion performance,EMI shielding ternary MXene/ANF–MoS_(2)composite films could be applied in many industrial *** work broadens how to achieve a balance between mechanical properties and versatility of composites in the case of high-function fillers.

关键词： MXene-MoS_(2) Lubrication toughening EMI shielding Photothermal conversion Electric heating performance

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钩吻现代功效研究进展

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现代中药研究与实践 2017年第5期31卷 74-77页

作者：宋恩峰张彩蝶武汉大学人民医院中医科湖北武汉430060

目的钩吻在我国民间治疗范围广泛,可用于治疗肿瘤、疼痛、类风湿等多种疾病。然而误服中毒甚至死亡的情况也时有发生,需要了解其现代功效,进一步应用于临床。方法随着近代实验研究和药理研究的发展,特别是在治疗肿瘤及疼痛方面的研究。... 详细信息

目的钩吻在我国民间治疗范围广泛,可用于治疗肿瘤、疼痛、类风湿等多种疾病。然而误服中毒甚至死亡的情况也时有发生,需要了解其现代功效,进一步应用于临床。方法随着近代实验研究和药理研究的发展,特别是在治疗肿瘤及疼痛方面的研究。通过大量阅读钩吻相关文献,对钩吻在抗肿瘤、镇痛剂其他作用进行综述。结果钩吻具有明显的抗肿瘤及镇痛作用,同时具有抗焦虑、修复放射损伤及放射增敏、造血保护、抗炎、抗曲霉菌等作用。结论钩吻具有良好的药用前景,为开发适合临床应用药物提供参考。

关键词：钩吻肿瘤疼痛现代功效

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Boosting charge extraction and efficiency of inverted perovskite solar cells through coordinating group modification at the buffer layer/cathode interface

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Nano Research 2025年第1期18卷 415-423页

作者： Zhiqing Liang Ziqiu Ren Ziyu Wang Nan Yan Ling Li Bo zhang Yanlin song College of Chemistry Zhengzhou UniversityZhengzhou 450052China Key Laboratory of Applied Surface and Colloid Chemistry Ministry of Education Shaanxi Key Laboratory for Advanced Energy DevicesShaanxi Engineering Lab for Advanced Energy Technology School of Materials Science and EngineeringShaanxi Normal UniversityXi’an 710119China Key Laboratory of Green Printing Institute of ChemistryChinese Academy of Sciences(ICCAS)Beijing Engineering Research Center of Nanomaterials for Green Printing TechnologyNational Laboratory for Molecular Sciences(BNLMS)Beijing 100190China

In inverted perovskite solar cells (PSCs),effective modification of the interface between the metalcathode and electron transport layer (ETL) is crucial forachieving high performance and stability. Herein, sulfonatedbathocuproine, commonly known as disodium bathocuproinedisulfonate (BCDS), was employed as a cathode buffer layerto address the interfacial issues at the [6,6]-phenyl-C61-butyricacid methyl ester (PCBM)/Ag interface. BCDS possesses theability to form coordinate bonds with Ag electrodes. Theutilization of the BCDS buffer layer enhanced the chargeextraction capability at the cathode interface whilesimultaneously achieving interfacial defect passivation,improving interfacial contact and increasing the built-in electricfield. Consequently, a power conversion efficiency (PCE) of25.06% was achieved. Furthermore, owing to the excellent filmforminguniformity of BCDS on PCBM, the stability of thedevice was also improved. After storage in dry air for morethan 2000 h, the device maintained 96% of its initial efficiency. This work underscores the remarkable potential of tailoringcoordination groups to enhance charge extraction efficiency at the ETL-cathode interface, unveiling a promising newfrontier in buffer layer development and performance optimization strategies for PSCs.

关键词： perovskite solar cells buffer layer bathocuproine disulfonate coordination group modification electron transport layer(ETL)-cathode interface

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