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Synthesis of Poly[2,2'-(m-phenylene)-5,5'-bibenzimidazole] and Poly(2,5-benzimidazole) by Microwave Irradiation

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Chemical Research in Chinese Universities 2009年第4期25卷 585-589页

作者： HE Rong-huan SUN bao-ying YANG Jing-shuai CHE quan-tong Department of Chemistry College of Sciences Northeastern University Shenyang 110004 P. R. China

A rapid way assisted by microwave irradiation was proposed to synthesize poly[2,2＇-（m-phenylene）-5,5＇-bibenzimidazole]（PBI） and poly（2,5-benzimidazole）（ab-PBI）.Synthesis of PBI in polyphosphoric acid is conducted for 20 h or even *** microwave irradiation,the polycondensations could be completed in polyphosphoric acid within 3 h from 3,3＇-diaminobenzidine tetrahydrochloride（DAB·4HCl·2H2O） and isophthalic acid for PBI,and from 3,4-diaminobenzoic acids（DABA） for ab-PBI,*** conditions for the polymerization including the power of microwave irradiation,temperature,heating time,and concentrations of the reactants in polyphosphoric acid were *** inherent viscosity of the polymers in concentrated sulfuric acid at 30 ℃ was 0.9766 dL/g for PBI,and 0.6480 dL/g for ab-PBI,*** of the polymer products was made by nuclear magnetic resonance（1^H NMR）,Fourier transform infrared spectra（FTIR） and thermogravimetric analysis（TGA）.

关键词： Microwave irradiation Polybenzimidazole Polycondensation Synthesis

A tunable ionic covalent organic framework platform for efficient CO_(2) catalytic conversion

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Frontiers of Chemical Science and Engineering 2024年第1期18卷 25-36页

作者： Ting Li Ji Xiong Minghui Chen quan Shi Xiangyu Li Yu Jiang Yaqing Feng bao Zhang School of Chemical Engineering and Technology Tianjin UniversityTianjin 300350China Guangdong Laboratory of Chemistry and Fine Chemical Industry Jieyang Center Jieyang 522000China Haihe Laboratory of Sustainable Chemical Transformations Tianjin 300192China

The cycloaddition reaction between epoxides and CO_(2) is an effective method to utilize CO_(2) *** organic frameworks(COFs)provide a promising platform for the catalytic CO_(2) transformations on account of their remarkable chemical and physical ***,a family of novel vinylene-linked ionic COFs named TE-COFs(TTE-COF,TME-COF,TPE-COF,TBE-COF)has been facilely synthesized from N-ethyl2,4,6-trimethylpyridinium bromide and a series of triphenyl aromatic aldehydes involving different numbers of nitrogen atoms in the central aromatic *** resulting catalyst TTE-COF with excellent adsorption capacity(45.6 cm3·g^(-1),273 K)exhibited outstanding catalytic performance,remarkable recyclability and great substrate ***,it was also observed that the introduction of nitrogen atom in the precursor led to a great improvement in the crystallinity and CO_(2) adsorption capacity of TE-COFs,thus resulting to a progressively improved catalytic *** work not only illustrated the influence of monomer nitrogen content on the crystallinity and CO_(2) adsorption capacity of TE-COFs but also provided a green heterogeneous candidate for catalyzing the cycloaddition between CO_(2) and epoxides,which shed a light on improving the catalytic performance of the CO_(2) cycloaddition reaction by designing the covalent organic frameworks structures.

关键词： CO_(2)cycloaddition nreaction covalent organic frameworks cyclic carbonate vinylene-linked synergetic effects

Phosphorylation of Microtubule-associated Protein SB401 from Solanum berthaultii Regulates Its Effect on Microtubules

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Journal of Integrative Plant Biology 2009年第3期51卷 235-242页

作者： bao-quan Liu Lifeng Jin Lei Zhu Jiejie Li Shuli Huang Ming Yuan State Key Laboratory of Plant Physiology and Biochemistry Department of Plant Sciences College of Biological Sciences China Agricultural University Beijing 100094 China Department of Biological Engineering College of Life Sciences Dalian Nationalities University Dalian 116600 China

We reported previously that the protein SB401 from Solanum berthaultii binds to and bundles both microtubules and F-actin. In the current study, we investigated the regulation of SB401 activity by its phosphorylation. Our experimental results showed that the phosphorylation of SB401 by casein kinase II （CKII） downregulates the activities of SB401, namely the bundling of microtubules and enhancement of the polymerization of tubulin. However, phosphorylation of SB401 had no observable effect on its bundling of F-actin. Further investigation using extract of potato pollen indicated that a CKIl-like kinase may exist in potato pollen. Antibodies against CKII alpha recognized specifically a major band from the pollen extract and the pollen extract was able to phosphorylate the SB401 protein in vitro. The CKIl-like kinase showed a similar ability to downregulate the bundling of microtubules. Our experiments demonstrated that phosphorylation plays an important role in the regulation of SB401 activity. We propose that this phosphorylation may regulate the effects of SB401 on microtubules and the actin cytoskeleton.

关键词： F-actin microtubule-associated protein microtubules phosphorylation Solanum berthaultii.

Electrolyte composition and galvanic corrosion for ruthenium/copper electrochemical mechanical polishing

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Rare Metals 2020年第11期39卷 1300-1306页

作者： Yan-Fei Bian Wen-Jie Zhai Yuan-Yuan Cheng bao-quan Zhu School of Mechatronics Engineering Harbin Institute of TechnologyHarbin150001China School of Civil Engineering Harbin Institute of TechnologyHarbin150001China

Electrochemical mechanical polishing(ECMP)is a new and highly promising technology.A specific challenge for integrating Ru as barrier in Cu interconnect structures is the galvanic corrosion of Cu that occurs during *** mitigate the problem,the benzotriazole(BTA)and ascorbic acid(AA)were chosen as selective anodic and cathodic inhibitors for Cu and Ru,*** optimization of electrolytes at different pHs including BTA,hydroxyethylidenediphosphoric acid(HEDP),and AA were investigated using electrochemical *** Ru/Cu removal rate and the planarization efficiency during Ru/Cu ECMP can be approximated using electrochemical measurements of the removal rate,with and without surface *** systems that exhibit a 1:1 selectivity between the barrier layer and copper would be ideal for the barrier removal step of *** slurry consists of 20.0 wt%HEDP,0.5 wt%BTA,and 0.3 wt%AA at pH *** the optimized slurry,the selectivity of Ru to Cu is near *** measurements of open circuit potentials,potentiodynamic polarization,and impedance spectroscopy were performed to investigate the galvanic corrosion between ruthenium and copper.

关键词： Electrochemical mechanical polishing Electrolyte composition Galvanic corrosion Benzotriazole Ascorbic acid

Spatial distribution and dynamics of carbon storage in natural Larix gmelinii forest in Daxing'anling mountains of Inner Mongolia,northeastern China

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Journal of Mountain Science 2017年第8期14卷 1633-1641页

作者： MENG Sheng-wang LIU Qi-jing JIA quan-quan ZHUANG Hui-xia QI Ying LU Cheng-xue DENG Liu-bao College of Forestry Beijing Forestry University Forestry Industry Bureau of Inner Mongolia

In order to clarify the geographic distribution and change of natural Larix gmelinii forest in carbon storage in Daxing'anling mountains(Great Khingan Range) in North China's Inner Mongolia, an area-irrelevant conversion equation of biomass from timber volume in the form of B = 0.6966 V was developed by using survey data. Based on the equation, the carbon storage was estimated at 190.172 Tg, and the average carbon density was 41.659 Mg/hm^2(area 4.565 × 10~6 hm^2). Carbon stored in standing trees was predominantly distributed in mid-age and mature forests and mainly stocked in the northern part of the study area. Assuming the carbon density of intact area as the maximum value, the potential carbon storage in the entire study area would be 263.674 Tg, approximately 1.4 times of the actual level. Over the period of 1995 to 2010, the carbon storage and carbon densityincreased by 3.260 Tg and 0.224 Mg/hm^2, respectively, indicating a weak carbon sink. Comparing with China's national average level, the carbon density in this area is not as high as expected. Forest quality in terms of carbon capacity is expected to be enhanced by appropriate management schemes under the in-implementation program of forest protection.

关键词： Biomass conversion equation Carbonstorage Great Khingan Range Distribution Larixgmelinii

Tricarboxy Ligand CuⅡ Metal-organic Framework with Magnetic and Proton Conduction Properties

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Chinese Journal of Structural Chemistry 2020年第9期39卷 1689-1693,1556页

作者： SHEN Zhi LUO bao-Min XIE Hai-quan ZHAO Qiang College of Chemistry and Pharmaceutical Engineering Nanyang Normal UniversityNanyang 473061China

Hydrothermal reaction of Cu(NO3)2·3 H2O and 4-(4-carboxyphenoxy)isophthalic acid(H3cpia)results in a two-dimensional coordination polymer based on paddle-wheel-like dinuclear clusters,namely[C60H54Cu4O39]n(1).Complex 1 is of triclinic system,space group P1 with a=10.7318(18),b=12.267(2),c=14.528(2)?,α=113.560(2)o,β=96.156(3)o,γ=103.552(3)o,V=1660.5(5)?3,Z=1,S=1.057,F(000)=842,R=0.0517 and wR=0.1426(I>2σ(I)).In this structure,tricarboxylate liagnds are partial deprotonation and potenial proton *** antiferromagnetic interaction between CuⅡions exists within the Cu2 cluster and complex 1 exhibits relatively high proton conductivity(σ>1.23×10-5 S×cm-1)at 76%relative humidity(RH).

关键词： metal-organic framework tricarboxylate ligands magnetic properties proton conductivity

Strain transfer of surface-bonded fiber Bragg grating sensors for airship envelope structural health monitoring

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2012年第7期13卷 538-545页

作者： Hai-tao ZHAO quan-bao WANG Ye QIU Ji-an CHEN Yue-ying WANG Zhen-min FAN School of Aeronautics and Astronautics Shanghai Jiao Tong UniversityShanghai 200240China

This paper deals with an improved bonding approach of surface-bonded fiber Bragg grating (FBG) sensors for airship envelope structural health monitoring (SHM) under the strain transfer theory. A theoretical formula is derived from the proposed model to predict the strain transfer relationship between the airship envelope and fiber core. Then theoretical predictions are validated by numerical analysis using the finite element method (FEM). Finally, on the basis of the theoretical approach and numerical validation, parameters that influence the strain transfer rate from the airship envelope to fiber core and the ratio of effective sensing length are analyzed, and some meaningful conclusions are provided.

关键词： airship envelope Fiber Bragg grating (FBG) Surface-bonded Strain transfer Structural health monitoring (SHM)

Microstructure and mechanical property of MIM 418 superalloy

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Rare Metals 2018年第1期37卷 35-39页

作者： Fu-bao Yang Yan-Hong Jing Dan Li Lin Zhang Da-quan Li Qiang Zhu National Engineering and Technology Research Center for Nonferrous Metal Matrix Composites General Research Institute for Nonferrous Metals Powder Metallurgy Research Institute University of Science and Technology Beijing

In this study, the influence of hot isostatic pressing（HIP） process on the 418 alloy produced by metal injection molding（MIM） technique（named as MIM 418）was investigated based on the characteristic analysis of 418 alloy powder. And comparison analysis of the microstructure and mechanical property between the MIM 418 and as-cast 418 alloys was performed by scanning electron microscopy（SEM）, energy-dispersive spectroscopy（EDS）,and X-ray diffraction（XRD）. The results show that MIM418 alloy exhibits fine grain（~30 μm） and uniform microstructure. The defects existing in MIM 418 alloy formed during sintering process can be eliminated through HIP treatment, and the relative density increases from97.0 % to 99.5 %. The mechanical property can be improved significantly because of the elimination of defects, and the tensile strength and elongation are1,271 MPa and 16.8 %, respectively, which are increased by 34.5 % and 180 % compared with K418 alloy after solution heat treatment.

关键词： K418 superalloy Metal injection molding Hot isostatic pressing Microstructure Mechanical property

Stability and Passivity Analysis for Lur'e Singular Systems with Markovian Switching

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International Journal of Automation and computing 2013年第1期10卷 79-84页

作者： Ping-Fang Zhou Yue-Ying Wang quan-bao Wang Ji-An Chen Deng-Ping Duan School of Aeronautics and Astronautics Shanghai Jiao Tong University

This paper is concerned with the stochastic stability and passivity analysis for a class of Lur’e singular systems with time-varying delay and Markovian switching. By using the free-weighting matrices approach, a delay-dependent stability criterion, which guarantees that the system is stochastically stable and robustly passive, is derived in terms of linear matrix inequality （LMI）. Two numerical examples are provided to illustrate the effectiveness of the proposed method. 更多还原

关键词： Lur’e singular time-delay systems Markovian jump systems delay-dependent passivity linear matrix inequality (LMI)