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Chinese Journal of Polymer Science 2015年第9期33卷 1225-1233页

作者： Li-mei Wang 张奇峰 suo-bo Zhang College of Materials Science and Engineering Jilin Jianzhu University Key Laboratory of Polymer Ecomaterials Changchun Institute of Applied Chemistry Chinese Academy of Sciences

A series of cardo poly（aryl ether sulfone） copolymers bearing pendent sulfonic acid groups （SPES-X） have been prepared by a facile chemical graft method. The structure was confirmed by 1H-NMR spectra. The side-chain-type SPES-X membranes show significantly reduced swelling behavior and excellent mechanical properties as well as appropriate proton conductivity compared to the main-chain-type sulfonated polymers with similar ion exchange capacity （IEC） value. Moreover, they show methanol permeability in the range of 0.6 × 10^-7-5.7 × 10^-7 cmE/s which is lower than that of Nafion 117. All the results indicate that the SPES-Xmembranes are promising candidates for the direct methanol fuel cells.

关键词： Side-chain type Cardo poly(aryl ether sulfone) Proton exchange membrane.

Reducing partition skew on MapReduce: an incremental allocation approach

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Frontiers of Computer Science 2019年第5期13卷 960-975页

作者： Zhuo WANG Qun CHEN bo suo Wei PAN Zhanhuai LI School of Computer Science and Engineering North Western Polytechnical UniversityXi’an 710072 China

MapReduce,a parallel computational model,has been widely used in processing big data in a distributed *** of alternate map and reduce phases,MapReduce has to shuffle the intermediate data generated by mappers to *** key challenge of ensuring balanced workload on MapReduce is to reduce partition skew among reducers without detailed distribution information on mapped *** this paper,we propose an incremental data allocation approach to reduce partition skew among reducers on *** proposed approach divides mapped data into many micro-partitions and gradually gathers the statistics on their sizes in the process of *** micropartitions are then incrementally allocated to reducers in multiple *** propose to execute incremental allocation in two steps,micro-partition scheduling and micro-partition *** propose a Markov decision process (MDP)model to optimize the problem of multiple-round micropartition scheduling for allocation *** present an optimal solution with the time complexity of O(K· N2),in which K represents the number of allocation rounds and N represents the number of ***,we also present a greedy but more efficient algorithm with the time complexity of O(K.N ln N).Then,we propose a minmax programming model to handle the allocation mapping between micro-partitions and reducers,and present an effective heuristic solution due to its ***,we have implemented the proposed approach on Hadoop,an open-source MapReduce platform,and empirically evaluated its *** extensive experiments show that compared with the state-of-the-art approaches,the proposed approach achieves considerably better data load balance among reducers as well as overall better parallel performance.

关键词： incremental partitioning data balance MapReduce

Extended π-conjugated N-containing heteroaromatic hexacarboxylate organic anode for high performance rechargeable batteries

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Journal of Energy Chemistry 2020年第12期29卷 303-311页

作者： Shu-Biao Xia Teng Liu Wen-Jin Huang Hong-bo suo Fei-Xiang Cheng Hong Guo Jian-Jun Liu Center for Yunnan-Guizhou Plateau Chemical Functional Materials and Pollution Control Qujing Normal UniversityQujing 655011YunnanChina School of Pharmacy Liaocheng UniversityLiaocheng 252059ShandongChina School of Materials Science and Engineering Yunnan UniversityKunming 650091YunnanChina

Organic electrode materials are desirable for green and sustainable Li-ion batteries(LIBs) due to their light-weight, low cost, abundance and multi-electron transfer reactions during battery operation. However, the successful utilization of organic electrodes is hindered by their poor electrical conductivity and low cyclic stability. Herein, a facile synthesis of π-conjugated N-containing heteroaromatic hexacarboxylate(Li6-HAT) compound and its electrochemical performance as an anode material in LIBs is *** as-synthesized Li6-HAT electrode renders an ultrahigh initial capacity of 1126.3 m Ah g^(-1) at the current density of 100 m A g^(-1). Moreover, π-conjugated N-containing heteroaromatic center provide excellent reversibility of(de)lithiation process, resulting in excellent capacity retention. Furthermore, a combination of density functional theory(DFT) calculations, in-situ Fourier transform infrared(FTIR) and ex-situ X-ray photoelectron spectroscopy(XPS) characterization reveal that the π-conjugated nitrogen and carboxyl oxygen act as electrochemically active sites during the charge/discharge process. The current work provides novel insights into the charge storage mechanism of organic electrodes and opens up avenues for further development and utilization of organic electrodes in Li-ion batteries.

关键词： Li-ion batteries Hexacarboxylate π-conjugated compounds N-containing Organic anode

Synthesis, Crystal Structure and Reactivity of (2,4-C_7H_(11) )_2Yb·DME

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Chemical Research in Chinese Universities 2001年第1期17卷 14-19页

作者： ZHANG suo-bo LIU Ju-zheng ZHUANG Xiu-li HUANG Jing-qin HU Ning-hai CHEN Wen-qi Department of Chemistry Jilin UniversityChangchun 130023P.R.China Changchun Institute of Applied Chemistry Chinese Academy of SciencesChangchun 130022P.R.China

(2,4 C 7H 11 ) 2Yb·DME was synthesized by the reaction of YbCl 3 with K(2,4 C 7H 11 )(2,4 dimethylpentadienyl potassium), and the single crystal X ray diffraction showed that the complex exists in a cis staggered conformation. The crystal of the compound belongs to the monoclinic space group P2 1/n with a =0.875 2 (1) nm, b =1.490 6(1) nm, c =1.529 3(2) nm, β =97 55(2)° , V =1.977 79(4) nm 3, Z =4, F (000)=735.8 e, μ =49.49 cm -1 , R =0.033 and R w=0.032 . The title complex can be used as a catalyst for the polymerization of methyl methacrylate(MMA).

关键词： Dimethylpentadienyl Synthesis Crystal structure Catalyst Polymerization

Aryl-guanidine/Pd-catalyzed Suzuki Cross-coupling Reaction at Room Temperature

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Chemical Research in Chinese Universities 2012年第2期28卷 242-244页

作者： LI Yan-chun LIN Ying-jie ZHANG suo-bo LI Sheng-hai DUAN Hai-feng Departent of Organic Chemistry College of ChemistryJilin UniversityChangchun 130012P.R.China Key Laboratory of Polymer Ecomaterials Changchun Institute of Applied ChemistryChinese Academy of SciencesChangchun 130022P.R.China

Four aryl-guanidines（AG） were synthesized and used for the palladium-catalyzed Suzuki cross-coupling reaction to test the catalytic *** the presence of steric bulk AG,when aryl bromide and arylboronic acid were used as the reactants,the Suzuki reaction could be carried out smoothly at room temperature in aqueous solvent to afford the cross-coupling product in high *** catalysis system was also successful for the coupling of activated aryl chlorides at room temperature.

关键词： Aryl-guanidine Suzuki reaction Palladium Ligand

Regulation of Water Deficit-Induced Abscisic Acid Accumulation by Apoplastic Ascorbic Acid in Maize Seedlings

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Journal of Integrative Plant Biology 2005年第11期47卷 1335-1344页

作者： Jian-Fang HU Gui-Fen LI Zhi-Hui GAO Lin CHEN Hui-bo REN Wen-suo JIA College of Agronomy and Biotechnology State Key Laboratory of Plant Physiology and Biochemistry China Agricultural University Beijing 100094 China

Water deficit-induced abscisic acid （ABA） accumulation is one of the most important stress signaling pathways in plant cells. Redox regulation of cellular signaling has currently attracted particular attention, but much less is known about its roles and mechanisms in plant signaling. Herein, we report that water deficit-induced ABA accumulation could be regulated by ascorbic acid （AA）-controlled redox status in leave apoplast. The AA content in non-stressed leaves was approximately 3 umol/g FW, corresponding to a mean concentration of 3 mmol/L in a whole cell. Because AA is mainly localized in the cytosol and chloroplasts, the volume of which is much smaller than that of the whole cell, AA content in cytosolic and chloroplast compartments should be much higher than 3 mmol/L. Water deficit-induced ABA accumulation in both leaf and root tissues of maize seedlings was significantly inhibited by AA and reduced glutathione （GSH） at concentrations of 500 umol/L and was completely blocked by 50 mmol/L AA and GSH. These results suggest that the AA-induced inhibition of ABA accumulation should not occur at sites where AA exists in high concentrations. Although water deficit led to a small increase in the dehydroascorbic acid （DHA） content, no significant changes in AA content were observed in either leaf or root tissues. When compared with the whole leaf cell, the AA content in the apoplastic compartment was much lower （i.e. approximately 70 nmol/g FW, corresponding to 0.7 mmol/L）. Water deficit induced a significant decrease （approximately 2.5-fold） in the AA content and an increase （approximately 3.4-fold） in the DHA content in the apoplastic compartment, thus leading to a considerably decreased redox status there, which may have contributed to the relief of AA-induced inhibition of ABA accumulation, alternatively, promoting water deficit-induced ABA accumulation. Reactive oxygen species （ROS） could not mimic water deficit in inducing ABA accumulation, suggesting that the

关键词： abscisic acid (ABA) ascorbic acid (AA) maize (Zea mays) reactive oxygen species waterdeficit.

Synthesis and Crystal Structure of[(2 , 4-Me_2C_5H_5)_2NdC =CC_6H_5]_2

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Chemical Research in Chinese Universities 1994年第4期10卷 308-312页

作者： Zhang, suo-bo Liu, Ju-zheng Wei, Ge-cheng Jia, Heng-qing Chen, Wen-qi

he reaction of (2, 4-C_7H_11)_3Nd with HC=CC_6H_5 in toluene leads to [(2, 4-C_7H_11)_2NdC = CC_6H_5]_2 , which crystallizes in the space group P_cab with unit cell pa-rameters a=1 . 0489 (11), b=1.8033 (12), c=2. 1064 (15)nm and Z=4 , least-squares refinement based on 2323 observed reflections converged to a final R valueof 0. 08. The molecular structure shows that the complex is a dimer, in which two(2,4-C_7H_11)_2Nd units are connected by asymmetrical alkynide bridges with indepen-dent Nd-C(alkynide) bond lengths of 0. 2552(25)and 0. 2560(24)nm, Nd-C=C angles of 124. 1(17)° and 134. 2(17)°.

关键词： Synthesis Structure Tris (2 4-dimethylpentadienyl ) neodymium.Phenylacetylene

Synthesis and Crystal Structure of Bis（tetra－hydrofurfurylcyclopentadienyl）ytterbium Chloride

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Chemical Research in Chinese Universities 1994年第3期10卷 254-255页

作者： ZHUANG Xiu-li ZHANG suo-bo HU Ning-hai and CHEN Wen-qi ( Changchun Inistitute of Applied Chemistry, Academia Sinica , Changchun , 130022)

ＳｙｎｔｈｅｓｉｓａｎｄＣｒｙｓｔａｌＳｔｒｕｃｔｕｒｅｏｆＢｉｓ（ｔｅｔｒａ－ｈｙｄｒｏｆｕｒｆｕｒｙｌｃｙｃｌｏｐｅｎｔａｄｉｅｎｙｌ）ｙｔｔｅｒｂｉｕｍＣｈｌｏｒｉｄｅＺＨＵＡＮＧＸｉｕ－ｌｉ；ＺＨＡＮＧＳｕｏ... 详细信息

ＳｙｎｔｈｅｓｉｓａｎｄＣｒｙｓｔａｌＳｔｒｕｃｔｕｒｅｏｆＢｉｓ（ｔｅｔｒａ－ｈｙｄｒｏｆｕｒｆｕｒｙｌｃｙｃｌｏｐｅｎｔａｄｉｅｎｙｌ）ｙｔｔｅｒｂｉｕｍＣｈｌｏｒｉｄｅＺＨＵＡＮＧＸｉｕ－ｌｉ；ＺＨＡＮＧＳｕｏ－ｂｏ；ＨＵＮｉｎｇ－ｈａｉａｎｄ...

关键词： Synthesis Structure Tetrahydrofurfurylcyclopentadienyl,Ytterbium

CATALYSIS OF METALLO-PORPHYRINS IN OXIDATION OF P-NITROTOLUENE BY ELECTRO-GENEEATED SUPEROXIDE ION

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Chinese Chemical Letters 1992年第7期3卷 499-502页

作者： Su Fang WANG Hong Sheng LU suo bo ZHANG Yin Jie LIN Ying Kai XU Department of chemistry Jilin University.The National Laboratory of Enzyme Engineering.Changchun130023

The oxidation of pnitrotoluene with electro-generated superoxide ion in the presence or absence of metallo-porphyrins FeTPP, MnTPP and CoTPP in DMF was studied by cyclic voltammetry and controlled potential electrolysis, Metallo-porphyrins as catalysts for electroreduction of O_2, they can not only increase yields of p-nitrobensoic acid and selectivities of reaction but also enable the reaction proceed at lower negative potential.

关键词： TPP CATALYSIS OF METALLO-PORPHYRINS IN OXIDATION OF P-NITROTOLUENE BY ELECTRO-GENEEATED SUPEROXIDE ION 台五

Comparison of food sources of Pinctada fucata,***,*** and Pteria penguin using lipid and fatty acid biomarkers

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Comparison of food sources of Pinctada fucata,***,*** and Pt...