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Synthesis of polyurea from 1,6-hexanediamine with CO_2 through a two-step polymerization

green Energy & Environment 2017年第4期2卷 370-376页

作者： Shan Jiang Ruhui Shi Haiyang Cheng Chao Zhang Fengyu Zhao School of Chemical Engineering Changchun University of Technology State Key Laboratory of Electroanalytical Chemistry Changchun Institute of Applied Chemistry Chinese Academy of Sciences Jilin Province Key Laboratory of Green Chemistry and Process Changchun Institute of Applied Chemistry Chinese Academy of Sciences

Activation and transformation of CO_2 is one of the important issues in the field of green and sustainable chemistry. Herein, CO_2 as a carbonoxygen resource was converted to CO_2-polyurea with 1,6-hexanediamine through a two-step polymerization. The reaction parameters such as temperature, pressure and reaction time were examined; and several kinds of catalysts were screened in the absence and presence of NMP solvent. The formed oligomer and the final polyurea were characterized by FT-IR, VT-DRIFTS, NMR, XRD, AFM and their thermal properties were examined by TGA and DSC. It was confirmed that the final polyurea has a high thermal stability; the melting temperature is 269℃ and the decomposition temperature is above 300℃. It is a brittle polymer with a tensile strength of 18.35 MPa at break length of 1.64%. The polyurea has a stronger solvent resistance due to the ordered hydrogen bond in structure. The average molecular weight should be enhanced in the postpolymerization as the appearance, hydrogen bond intensity, crystallinity, melting point and the thermal stability changed largely compared to the oligomer. The present work provides a new kind of polyurea, it is expected to have a wide application in the field of polymer materials.

关键词： CO2 Polyurea Two-step polymerization Catalysis

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Inside Cover: Delicate Control on the Shell Structure of Hollow Spheres Enables Tunable Mass Transport in Water Splitting (Angew. Chem. Int. Ed. 13/2021)

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Angewandte Chemie International Edition 2021年第13期60卷

作者： Dr. Ping Hou Dr. Dan Li Prof. Nailiang Yang Prof. Jiawei Wan Dr. Chunhui Zhang Prof. Xiqi Zhang Dr. Hongyu Jiang Prof. Qinghua Zhang Prof. Lin Gu Prof. Dan Wang State Key Laboratory of Biochemical Engineering Institute of Process Engineering Chinese Academy of Sciences 1 North 2nd Street Zhongguancun Haidian District Beijing 100190 P. R. China University of Chinese Academy of Sciences 19A Yuquan Road Beijing 10049 P. R. China Laboratory of Bio-Inspired Materials and Interface Sciences Technical Institute of Physics and Chemistry Chinese Academy of Sciences Beijing 100190 P. R. China Institute of Physics Chinese Academy of Sciences Beijing 100190 P. R. China

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Delicate Control on the Shell Structure of Hollow Spheres Enables Tunable Mass Transport in Water Splitting

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Angewandte Chemie 2021年第13期133卷

In the study of structure–property relationships for rational materials design, hollow multishell structures (HoMSs) have attracted tremendous attention owing to the optimal balance between mass transfer and surface exposure. Considering the shell structure can significantly affect the properties of HoMSs, in this paper, we provide a novel one-step strategy to continually regulate the shell structures of HoMSs. Through a simple phosphorization process, we can effectively modify the shell from solid to bubble-like and even duplicate the shells with a narrow spacing. Benefitting from the structure merits, the fabricated CoP HoMSs with close duplicated shells can promote gas release owing to the unbalanced Laplace pressure, while accelerating liquid transfer for enhanced capillary force. It can provide effective channels for water and gas and thus exhibits a superior electrocatalytic performance in the hydrogen and oxygen evolution reaction.

关键词： duplicate shells hollow structures mass transport multi-shell structures water splitting

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Innentitelbild: Delicate Control on the Shell Structure of Hollow Spheres Enables Tunable Mass Transport in Water Splitting (Angew. Chem. 13/2021)

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Angewandte Chemie 2021年第13期133卷

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Photocatalysts: Steering Hollow Multishelled Structures in Photocatalysis: Optimizing Surface and Mass Transport (Adv. Mater. 44/2020)

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Advanced Materials 2020年第44期32卷

作者： Yanze Wei Nailiang Yang KeKe Huang Jiawei Wan Feifei You Ranbo Yu Shouhua Feng Dan Wang State Key Laboratory of Biochemical Engineering Institute of Process Engineering Chinese Academy of Sciences 1 North 2nd Street Zhongguancun Beijing 100190 P. R. China Department of Physical Chemistry School of Metallurgical and Ecological Engineering University of Science and Technology Beijing 30 Xueyuan Road Beijing 100083 P. R. China State Key Laboratory of Inorganic Synthesis and Preparative Chemistry Jilin University Changchun 130012 P. R. China

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CO_2 absorption with ionic liquids at elevated temperatures

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Journal of Energy Chemistry 2017年第5期26卷 1001-1006页

作者： Lu Bai Dawei Shang Mengdie Li Zhongde Dai Liyuan Deng Xiangping Zhang Key Laboratory of Green Process and Engineering State Key Laboratory of Multiphase Complex System Beijing Key Laboratory of Ionic Liquids Clean Process Institute of Process Engineering Chinese Academy of Sciences Department of Chemical Engineering Norwegian University of Science and Technology (NTNU)

COcapture with ionic liquids（ILs） has attracted many attentions, and most works focused on absorption ability at ambient temperatures, while seldom research was concerned at elevated *** not only limits the COabsorption application at elevated temperature, but also the determination of the operation condition of the COdesorption generally occurring at higher temperature. This work mainly reported COsolubilities in ILs at elevated temperatures and related properties were also provided. 1-alkyl-3-methylimidazolium bis（trifluoromethylsulfonyl）imide（[CnMIm][TfN]） ILs were selected as physical absorbents for COcapture in this work due to their relative higher COabsorption capacities and good thermal stabilities. The long-term stability tests showed that [CnMIm][TfN] is thermally stable at 393.15 K for long time. COsolubilities in [CnMIm][TfN] were systematically determined at temperatures from 353.15 K to 393.15 K. It demonstrated that COsolubility obviously increases with the increase of pressure while slightly decreases with increase of temperature. As the length of alkyl chain on the cation increases, COsolubility in ILs increases. Additionally, the thermodynamic properties including the Gibbs free energy, enthalpy, and entropy of COwere also calculated.

关键词： Ionic liquids CO2 capture Elevated temperature Pre-combustion

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Acid‐Activatable Transmorphic Peptide‐Based Nanomaterials for Photodynamic Therapy

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Angewandte Chemie 2020年第46期132卷

作者： Bingbing Sun Rui Chang Shoupeng Cao Chengqian Yuan Luyang Zhao Haowen Yang Junbai Li Xuehai Yan Jan C. M. van Hest Bio-Organic Chemistry Institute of Complex Molecular Systems Department of Biomedical Engineering Eindhoven University of Technology P. O. Box 513 5600 MB Eindhoven The Netherlands State Key Laboratory of Biochemical Engineering Institute of Process Engineering Chinese Academy of Sciences Beijing 100190 China Laboratory of Immunoengineering Department of Biomedical Engineering Institute for Complex Molecular Systems Eindhoven University of Technology 5600 MB Eindhoven The Netherlands Beijing National Laboratory for Molecular Sciences CAS Key Laboratory of Colloid Interface and Chemical Thermodynamics Institute of Chemistry Chinese Academy of Sciences Beijing 100190 China

Inspired by the dynamic morphology control of molecular assemblies in biological systems, we have developed pH‐responsive transformable peptide‐based nanoparticles for photodynamic therapy (PDT) with prolonged tumor retention times. The self‐assembled peptide–porphyrin nanoparticles transformed into nanofibers when exposed to the acidic tumor microenvironment, which was mainly driven by enhanced intermolecular hydrogen bond formation between the protonated molecules. The nanoparticle transformation into fibrils improved their singlet oxygen generation ability and enabled high accumulation and long‐term retention at tumor sites. Strong fluorescent signals of these nanomaterials were detected in tumor tissue up to 7 days after administration. Moreover, the peptide assemblies exhibited excellent anti‐tumor efficacy via PDT in vivo. This in situ fibrillar transformation strategy could be utilized to design effective stimuli‐responsive biomaterials for long‐term imaging and therapy.

关键词： fibrillar transformation peptides photodynamic therapy photosensitizers self-assembly

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Upconversion 32Nb_(2)O_(5)-10La_(2)O_(3)-16ZrO_(2) glass activated with Er^(3+)/Yb^(3+) and dye sensitized solar cell application

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Journal of Advanced Ceramics 2017年第4期6卷 312-319页

作者： Xiaoyu LI Jiaying LI Jianqiang LI Hong LIN Bo LI National Engineering Laboratory for Hydrometallurgical Cleaner Production Technology Key Laboratory of Green Process and EngineeringInstitute of Process EngineeringChinese Academy of SciencesBeijing 100190China Advanced Materials Institute Graduate School at ShenzhenTsinghua UniversityShenzhenGuangdong 518055China University of Chinese Academy of Sciences Beijing 100049China State Key Laboratory of New Ceramics and Fine Processing Department of Materials Science and EngineeringTsinghua UniversityBeijing 100084China

Er^(3+)/Yb^(3+)codoped niobium pentoxide glasses were fabricated by the aerodynamic levitation(ADL)method with rapid cooling *** samples with various doping concentrations showed good upconversion luminescence properties under 980 nm laser *** structure,transmittance spectrum,and luminescence properties of the samples were systemically investigated by XRD,UV-Vis-NIR spectrophotometer,and upconversion *** transparent samples exhibited green and red upconversion emissions centered at 532,547,and 670 *** results showed that the sample codoped with 1 mol%Er^(3+)/Yb^(3+)has the strongest upconversion emissions,and the increase of the doped Yb^(3+)concentration results in the increased red emission and reduced green *** logI-logP plot of green emission indicated that the green emissions reach the saturation at high pump power excitation,deviating from the low-power *** one-photon energy transfer(ET)process,^(4)I_(11/2)+^(4)I_(11/2)→^(4)F_(7/2)+^(4)I_(15/2) process between the two neighboring Er^(3+)ions was responsible for the population of the 4S3/2/4H11/2 *** niobium pentoxide codoped with Er^(3+)/Yb^(3+)bulk glasses could be used in the dye sensitized solar cell(DSSC)to improve the efficiency.

关键词： aerodynamic levitation(ADL) niobium pentoxide upconversion rare earth concentration solar cell

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Synthesis of isosorbide-based polycarbonates via melt polycondensation catalyzed by quaternary ammonium ionic liquids

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Chinese Journal of Catalysis 2017年第5期38卷 908-917页

作者： Wei Sun Fei Xu Weiguo Cheng Jian Sun Guoqing Ning Suojiang Zhang College of Chemistry and Chemical Engineering China University of Petroleum‐Beijing Beijing 102249 China Key Laboratory of Green Process and Engineering Beijing Key Laboratory of Ionic Liquids Clean Process State Key Laboratory of Multiphase Complex Systems Institute of Process Engineering Chinese Academy of Sciences Beijing 100190 China

A series of quaternary ammonium ionic liquids(ILs)were synthesized and employed as catalysts for the production of poly(isosorbide carbonate)(PIC)from diphenyl carbonate and isosorbide via a melt polycondensation *** relationship between the anions of the ILs and the catalytic activities was investigated,and the readily‐prepared IL tetraethylammonium imidazolate(TEAI)was found to exhibit the highest catalytic *** optimizing the reaction conditions,a PIC with a weight‐average molecular weight(Mw)of25600g/mol was obtained,in conjunction with an isosorbide conversion of92%.As a means of modifying the molecular flexibility and thermal properties of the PIC,poly(aliphatic diol‐co‐isosorbide carbonate)s(PAIC)s were successfully synthesized,again using TEAI,and polymers with Mw values ranging from29000to112000g/mol were obtained.13C NMR analyses determined that the PAIC specimens had random microstructures,while differential scanning calorimetry demonstrated that each of the PAICs were amorphous and had glass transition temperatures ranging from50to115°*** analyses found Td‐5%values ranging from316to332°C for these *** on these data,it is evident that the incorporation of linear or cyclohexane‐based diol repeating units changed the thermal properties of the PIC.

关键词： Quaternary ammonium ionic liquid catalyst Isosorbide Polycarbonate Melt polycondensation Aliphatic diol

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Sequential Templating Approach: Sequential Templating Approach: A Groundbreaking Strategy to Create Hollow Multishelled Structures (Adv. Mater. 38/2019)

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Advanced Materials 2019年第38期31卷

作者： Dan Mao Jiawei Wan Jiangyan Wang Dan Wang State Key Laboratory of Biochemical Engineering Institute of Process Engineering Chinese Academy of Sciences No. 1 Beiertiao Zhongguancun Haidian District Beijing 100190 China

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