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侧链含氮原子磺化聚酰亚胺膜材料的制备及其性能研究

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高分子学报 2014年第8期24卷 1096-1102页

作者：李玉邯金日哲高连勋吉林工商学院实验中心长春130062 中国科学院长春应用化学研究所长春130022

以对苯二酚为原料经过三步反应,合成了含叔胺取代基的二胺单体2,5-二((二甲氨基)亚甲基)-1,4-二(对氨基苯氧基)苯(DMAPB),并与1,4,5,8-四酸萘二酐(NTDA)、磺化二胺4,4'-二氨基二苯醚-2,2'-二磺酸(ODADS)高温聚合,通过改变磺化二胺单体(O... 详细信息

以对苯二酚为原料经过三步反应,合成了含叔胺取代基的二胺单体2,5-二((二甲氨基)亚甲基)-1,4-二(对氨基苯氧基)苯(DMAPB),并与1,4,5,8-四酸萘二酐(NTDA)、磺化二胺4,4'-二氨基二苯醚-2,2'-二磺酸(ODADS)高温聚合,通过改变磺化二胺单体(ODADS)的含量,制备了一系列具有不同磺化度的侧链含氮原子磺化聚酰亚胺.采用间甲酚为溶剂,通过溶液浇铸法制备成膜.由于将N-原子引入到聚酰亚胺的侧链,使得其与磺酸基更易形成较强的离子交联,从而有效地控制膜溶胀,提高了膜稳定性.新的磺化聚酰亚胺的热稳定性高达330℃并显示了良好的氧稳定性,其阻醇性能也得到了提高,在20℃下,膜的甲醇渗透系数为2.05×10-7至5.11×10-7cm2/s,远低于Nafion 117(2×10-6cm2/s)一个数量级.磺化度40%的磺化聚酰亚胺膜在100℃去离子水中测试1000 h以上仍能保持较好的机械性能.膜在高湿条件下也显示了良好的机械性能.然而,膜的质子传输率有所下降,这应该是较强的离子交联导致膜产生较致密的结构,减少了含水量并阻碍了水和H+的移动.同时,磺酸基与氮原子发生离子交联,减少了参与质子传输的磺酸基数量,降低了聚合物膜的酸性.

关键词：磺化聚酰亚胺酸碱交联质子交换膜燃料电池

Crystal Structure and Solution Behavior of a Novel Enantiopure Helical Coordination Polymer Based on Binaphthyl-bisbipyridine Ligand

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Chemical Research in Chinese Universities 2010年第6期26卷 857-861页

作者： jin ri-zhe BIAN zheng HE Ya-bing GAO Lian-xun State Key Laboratory of Polymer Physics and Chemistry Changchun Institute of Applied Chemistry Chinese Academy of Sciences Changchun 130022 P R. China Graduate School of Chinese Academy of Sciences Beijing 100049 P R. China

An enantiopure helical coordination polymer AgPF6·（R）-3 as crystalline solid was synthesized by the self-assembly of chiral binaphthyl-based ligand（R）-6,6＇-di[6-（2,2＇-bipyridyl）]-2,2＇-diethoxyl-1,1＇-binaphthalene [（R）-3] and Ag＋ *** single crystal structural analysis indicates that this polymer exhibits an infinite cylindric single-stranded M-helical structure with local Λ configuration at each tetrahedral metal ***,the extended structure is dissociated into some oligomeric fragments in *** 1H NMR spectra of complex AgPF6·（R）-3 show that the ligand possesses a good C2 symmetry,and the chemical shifts of the protons depend on the concentration and *** addition,there are rapid dynamic exchanges among some oligonuclear fragments in the solution of AgPF6·（R）-3.

关键词： Helical structure Binapthyl Silver Chiral ligand Solution behaviour

Synthesis and Characterization of Novel Sulfonated Polyimides from 4,6-Bis（4-aminophenoxy）-naphthalene-2-sulfonic Acid

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Chemical Research in Chinese Universities 2013年第6期29卷 1225-1228页

作者： LI Yu-han WANG Wei-jian jin ri-zhe GAO Lian-xun College of Food Science and Engineering Jilin Business and Technology College Changchun 130062 P.R.China State Key Laboratory of Polymer Physics and Chemistry Changchun Institute of Applied ChemistryChinese Academy of Sciences Changchun 130022 P.R.China

A novel sulfonated diamine monomer, 4,6-bis（4-arninophenoxy）-naphthalene-2-sulfonic acid（BAPNS）, was synthesized. A series of sulfonated polyimide copolymers was prepared from BAPNS, 1,4,5,8-naphthalenetetracarboxylic dianhydride（NTDA） and nonsulfonated diamine 4,4＇-diaminodiphenyl ether（ODA）. Flexible, transparent, and mechanically strong membranes were obtained. The novel sulfonated polyimide（SPI） membranes show higher conductivity, for example, SPI-100 shows a conductivity of 0.0698 S/cm at 80℃（SPI-X： Xrefers to molar fraction of BAPNS）. The membranes exhibit the permeability of methanol from 2.18×10^-7 cm2/s to 2.57×10^-7 cm2/s, which is much lower than that of Nafion（2.00×10 6 cm^2/s）. The copolymers were thermally stable up to 330℃. The sulfonated polyimide copolymers also show reasonable mechanical strength; for example, the maximum tensile strength at break of the sulfonated polyimide copolymer with 100%（molar fraction） BAPNS is 1.35 GPa under high moisture condi- tions. The optimum concentration of BAPNS was found to be 100%（molar fraction） from the view point of proton conductivity, methanol permeability, and membrane stability.

关键词： Sulfonated polyimide Proton conductivity Proton-exchange membrane

Enantioselective Iodolactonizations of (E)-and (Z)-5-Substituted-4-pentenoic Acid Derivatives Mediated by Chiral Salen-Co(II) Complex

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Chemical Research in Chinese Universities 2011年第1期27卷 45-48页

作者： NING Zhao-lun DING jin-ying jin ri-zhe KANG Chuan-qing CHENG Yan-qin GAO Lian-xun State Key Laboratory of Polymer Physics and Chemistry Changchun Institute of Applied Chemistry Chinese Academy of Sciences Changchun 130022 P. R. China Graduate School of Chinese Academy of Scienees Beijing 100049 P. R. China

A number of salen-metal complexes were prepared and their enantioselective catalytic properties toward the asymmetric iodolactonization of （E）- and （Z）-5-substituted-4-pentenoic acid derivatives were investigated. The catalyst system based on salen-Co（II） complex exhibited moderate to good enantioselectivity with the e.e. value ranging from 53% to 74%, as well as high regioselectivity of δ- vs. γ-iodolactones. The salen-Co（II） complex showed the highest enantioselectivity on the asymmetric iodolactonizations of （Z）-5-substituted-4-pentenoic acid derivatives among these reagent-controlled iodolactonization protocols known so far.

关键词： Asymmetric catalysis Salen-complex Iodolactonization

Micromorphology and safety properties of meager and meager-lean coal for blast furnace injection

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International Journal of Minerals,Metallurgy and Materials 2021年第5期28卷 774-781页

作者： Long-zhe jin Xiao-meng Niu School of Civil and Resource Engineering University of Science and Technology BeijingBeijing 100083China

Four types of meager and meager-lean coal and one type of high-quality anthracite were selected based on the safety requirements for blast furnace coal injection and domestic coal quality to conduct microstructure and component *** analyses of the organic and inorganic macerals and the chemical compositions of the selected coal samples indicate that the four types of meager and meager-lean coal have low volatilization,low ash content,and low sulfur content;these qualities are suitable for blast furnace *** test was conducted on the four types of meager and meager-lean coal and the anthracite mixed coal *** indicate that the mixture of meager and meager-lean coal and anthracite is beneficial to improve the grindability of pulverized *** explosive tests reveal that the selected coal samples are non-explosive or weakly *** the proportion of meager and meager-lean coal is less than 40wt%,the mixed coal powder would not explode during the blowing *** minimum ignition temperature test determines that the minimum ignition temperatures of the four types of meager and meager-lean coal and anthracite are 326,313,310,315,and 393°C,*** study provides a guiding research idea for the safety of meager and meager-lean coal used in blast furnace injection.

关键词： meager coal meager-lean coal microstructure safety property blast furnace injection

Quantification of Effects of Natural Geographical Factors and Land-scape Patterns on Non-point Source Pollution in Watershed Based on Geodetector:Burhatong river Basin,Northeast China as An Example

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Chinese Geographical Science 2022年第4期32卷 707-723页

作者： SHI jinhao jin ri ZHU Weihong School of Geography and Ocean Sciences Yanbian UniversityHunchunChina Key Laboratory of Wetland Ecological Functions and Ecological Security HunchunChina

Changes in natural geographic features and landscape patterns directly influence the hydrology and non-point source pollution processes in the watershed;however,to slow down non-point source pollution,it is necessary to distinguish their *** the non-point source pollution process is interactional as a result of multiple factors,and the collinearity between multiple independent variables limits our ability of reason ***,taking the Burhatong river Basin,Northeast China as an example,the methods of hydrological simulation,geographic detectors,and redundancy analysis have been combined to determine the impact of natural geographic features and landscape patterns on non-point source pollution in the *** Soil&Water Assessment Tool(SWAT)has been adopted to simulate the spatial and temporal distribution characteristics of total nitrogen and total phosphorus in the *** results show that the proportions of agricultural land and forest area and the location-weighted landscape contrast index(LWLI)are the main indicators influencing the rivers total nitrogen and total *** interaction of these indicators with natural geographic features and landscape configuration indicators also significantly influences the changes in total nitrogen(TN)and total phosphorus(TP).Natural geographical features and landscape patterns have different comprehensive effects on non-point source pollution in the dry and wet *** and TP loads are affected mainly by the change in landscape pattern,especially in the wet *** the ecological restoration program has improved forest coverage,the purification effect of increased forest coverage on the water quality in the watershed may be offset by the negative impact of increased forest *** high concentration and complexity of farmland patches increase the risk of non-point source pollution spread to a certain extent.

关键词： Soil&Water Assessment Tool(SWAT)model Geodetector non-point source pollution impact factors redundancy ana-lysis

Volterra series based predistortion for broadband RF power amplifiers with memory effects

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Journal of Systems Engineering and Electronics 2008年第4期19卷 666-671页

作者： jin zhe Song Zhihuan He Jiaming zhejiang Univ. of Science and Technology Hangzhou 310023 P. R. China Coll. of Information Science and Engineering Zhejiang Univ. Hangzhou 310027 P. R. China Inst. of Communication Technologies Ningbo Univ. Ningbo 315211 P. R. China

RF power amplifiers （PAs） are usually considered as memoryless devices in most existing predistortion techniques. However, in broadband communication systems, such as WCDMA, the PA memory effects are significant, and memoryless predistortion cannot linearize the PAs effectively. After analyzing the PA memory effects, a novel predistortion method based on the simplified Volterra series is proposed to linearize broadband RF PAs with memory effects. The indirect learning architecture is adopted to design the predistortion scheme and the reeursive least squares algorithm with forgetting factor is applied to identify the parameters of the predistorter. Simulation results show that the proposed predistortion method can compensate the nonlinear distortion and memory effects of broadband RF PAs effectively.

关键词： power amplifiers predistortion memory effects Volterra series

Positron Spectroscopy of Free Volume in Poly(vinylidene fluoride) after Helium Ions Irradiation

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Chinese Journal of Polymer Science 2019年第5期37卷 527-534页

作者： jin-zhe Lyu Roman Laptev Natalya Dubrova Division for Experimental Physics School of Nuclear Science & EngineeringNational Research Tomsk Polytechnic University

Free volume is an extremely important intrinsic defect in polymers. Structurally, free volume is the randomly distributed holes in the polymer molecular chain segments. In proton exchange membrane fuel cells, free volume is also the space needed for the directional conduction of protons. Irradiation by α particles to grafting sulfonated poly(vinylidene fluoride)(PVDF) is one of the methods to produce proton exchange membrane with good proton channel rate. Positron annihilation lifetime spectroscopy was used to study the free volume size at different absorbed dose levels from 0.13 MGy to 0.65 MGy. Measurement method of positron annihilation lifetime spectroscopy for PVDF based on ^(44) Ti positron source was developed. For low dose irradiation at 0.26 MGy, a decrease in free volume and practically unchanged crystallinity were observed. Further increase of absorbed dose range from 0.26 MGy to 0.39 MGy led to an increasing crystallinity with the same free volume level. For the absorbed dose from 0.39 MGy to 0.65 MGy, crystallinity was decreased but free volume remained almost constant.

关键词： Positron annihilation Free volume XRD Poly(vinylidene fluoride) Helium ions Connection Degradation

Application of Short Sequential Extraction Procedure(SSEP) for the Determination of Zn, Cu, and Cd Contents in riverbed Sludge in Hejiagou, Harbin, China

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Chemical Research in Chinese Universities 2006年第6期22卷 696-702页

作者： LI Yu WANG zhe ZHAO Wen-jin Energy and Environment Research Center North China Electric Power University Beijing 102206 P. R. China College of Enviromnent and Resources Jilin University Changchun 130012 P. R. China Department of Internal Medicine of Digestion China -Japan Union Hospital Jilin University Changchun 130033 P. R. China

A short sequential extraction procedure（SSEP） was applied to the determination of more readily available metal fractions of Zn, Cu, and Cd in the riverbed sludge in Hejiagou, Harbin, China. From the results, a potential order of metal availability in seven sludge samples was proposed： Cd 〈 Cu 〈 Zn, and samples S1 , S2, and S4 were used for the determination of total Zn content, and sample S3 used for the determination of total Cu content in the mobile and the mobilizable fractions showed the highest pollution risk. The results with regard to metal mobility in sludge samples were confirmed by the individual and global contamination factors that were calculated from the nonresidual and residual metal contents. The results obtained from metal-release experiments after exposure of sludge to environmental conditions agreed well with those obtained from both SSEP and the individual and global contamination factors, indicating that the maximum metal release could be an additional factor to evaluate the heavy metal availability in contaminated sludge. A substantial time saving was achieved by using the metal-release method in the present study.

关键词： riverbed sludge Zn, Cu, and Cd Metal bioavailability Retention Release Sequential extraction procedure