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Propane dehydrogenation catalyzed by in-situ partially reduced zinc cations confined in zeolites

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Journal of Energy Chemistry 2021年第12期30卷 262-269,I0006页

作者： Linjun Xie Rui Wang Yuchao Chai Xuefei Weng Naijia Guan Landong Li School of Materials science and Engineering Nankai UniversityTianjin 300350China Vacuum Interconnected Nanotech Workstation Suzhou Institute of Nano-Tech and Nano-BionicsChinese Academy of SciencesSuzhou 215123JiangsuChina

Propane dehydrogenation(PDH), employing Pt-or Cr-based catalysts, represents an emerging industrial route for propylene production. Due to the scarcity of platinum and the toxicity of chromium, alternative PDH catalysts are being pursued. Herein, we report the construction of Zn-containing zeolite catalysts,namely Zn@S-1, for PDH reaction. Well-isolated zinc cations are successfully trapped and stabilized by the Si-OH groups in S-1 zeolites via in-situ hydrothermal synthesis. The as-prepared Zn@S-1 catalysts exhibit good dehydrogenation activity, high propylene selectivity, and regeneration capability in PDH reaction under employed conditions. The in-situ partial reduction of zinc species is observed and the partially reduced zinc cations are definitely identified as the active sites for PDH reaction.

关键词： Propane dehydrogenation Zinc catalysts Zn@S-1 In-situ reduction

Synthesis and Crystal Structure of a 1-D Coordination Polymer [Pb(ANS)_2(phen)]_n

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Chinese Journal of Structural Chemistry 2007年第6期26卷 717-720页

作者：崔增楠郭建华杨恩翠 College of Chemistry and Life science Tianjin Normal University

A new one-dimensional coordination polymer, [Pb（phen）（ANS）2]n （ANS = 2-aminonaphthalene-1-sulfonate, phen = 1,10-phenanthroline）, has been prepared by hydrothermal synthesis and structurally characterized by elemental analysis, IR and single-crystal X-ray diffraction. The results determined by XRD reveal that the complex crystallizes in monoclinic, space group P21/c with a = 16.8374（14）, b = 16.9825（14）, c = 9.9392 （8）A, β = 95.9830（10）°, V = 2826.5（4）A^3, Mr = 831.86, Dc = 1.955 g/cm^3, μ（MoKα） = 6.173 mm^-1, F（000） = 1624, Z = 4, the final R = 0.0272 and wR = 0.0694 for 4305 observed reflections （Ⅰ〉 2σ（Ⅰ））. In the complex, the adjacent lead（Ⅱ） ions are bridged through the oxygen atoms of sulfonate groups in a syn-syn conformation, yielding an infinite zigzag chain. And the intermolecular N-H…O hydrogen bonds link the chains into two-dimensional layered networks, which are further assembled into a separate two-layer-film-like packing structure.

关键词： lead-containing complex crystal structure hydrothermal synthesis

X-Ray Photoelectron Spectrum Analysis of Yb_(3)C_(60) Compound

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Chinese Physics Letters 2001年第5期18卷 656-658页

作者： CAO Xue-Wei SHAO Yue WANG Yu-Fang LAN Guo-Xiang Department of Physics Nankai UniversityTianjin 300071

The nominal composition of Yb_(3)C_(60) compound is characterised by means of x-ray photoelectron *** of the divalent state for the Yb cation in the as-grown crystalline Yb_(3)C_(60) is *** exposure to air the Yb_(3)C_(60) compound transforms to an amorphous phase and Yb_(2)O_(3) compound,while the valence state of the Yb cations changes from divalent to trivalent.

关键词： spectroscopy. compound divalent

Immobilization of carbonic anhydrase for facilitated CO2 capture and separation

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Chinese Journal of Chemical Engineering 2020年第11期28卷 2817-2831页

作者： Zhenhua Wu Yan Nan Yang Zhao Xueying Wang Shouying Huang Jiafu Shi Key Laboratory for Green Chemical Technology of Ministry of Education School of Chemical Engineering&TechnologyTianjin UniversityTianjin 300072China School of Environmental science&Engineering Tianjin UniversityTianjin 300072China Collaborative Innovation Center of Chemical science and Engineering Tianjin 300072China

Carbonic anhydrase(CA)as a typical metalloenzyme in biological system can accelerate the hydration/dehydration of carbon dioxide(CO2,the major components of greenhouse gases),which performer with high selectivity,environmental friendliness and superior ***,the free form of CA is quite expensive(~RMB 3000/100 mg),unstable,and non-reusable as the free form of CA is not easy for recovery from the reaction environment,which severely limits its large-scale industrial *** immobilization may solve these problems at the same *** this context,many efforts have been devoted to improving the chemical and thermal stabilities of CA through immobilization *** recently,a wide range of available inorganic,organic and hybrid compounds have been explored as carrier materials for CA immobilization,which could not only improve the tolerance of CA in hazardous environments,but also improve the efficiency and recovery to reduce the cost of large-scale application of *** excellent reviews about immobilization methods and application potential of CA have been *** contrast,in our review,we stressed on the way to better retain the biocatalytic activity of immobilized CA system based on different carrier materials and to solve the problems facing in practical operations *** concluding remarks are presented with a perspective on constructing efficient CO2 conversion systems through rational combining CA and advanced carrier materials.

关键词： Carbon dioxide Carbonic anhydrase Enzyme immobilization Capture and separation Carrier materials

Molecularly imprinted polymers with assistant recognition polymer chains for bovine serum albumin

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science China Chemistry 2010年第4期53卷 905-911页

作者： GUO MinJie1, GAO Ting1, FAN Zhi1, YAO JingXia1, XIA JianJun2 & MI HuaiFeng2 1Department of Chemistry, College of sciences, tianjin University of science and Technology, tianjin 300457, China 2Key Laboratory of Functional Polymer Materials, Ministry of Education Institute of Polymer Chemistry, Nankai University, tianjin 300071, China 1. Department of Chemistry College of Sciences Tianjin University of Science and Technology Tianjin 300457 China2. Key Laboratory of Functional Polymer Materials Ministry of Education Nankai University Tianjin 300071 China3. Institute of Polymer Chemistry Nankai University Tianjin 300071 China

A new protein molecularly imprinted polymer (MIP) was prepared with grafting polyvinyl alcohol as assistant recognition polymer chains (ARPCs). The ARPCs and acrylamide monomers were interpenetrated and then polymerized on the surface of macroporous acrylate adsorbent spheres. The template BSA was removed by treatment with 2.00 mol L-1 potassium chloride (KCl) solution and the adsorbed proteins were detected with sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE). 0.150, 0.500, and 2.00 mol L-1 KCl solutions were used as eluent to wash the adsorbed proteins. The SDS-PAGE results show that proteins washed out with 2.00 mol L-1KCl solution were from nonspecific adsorption of macroporous acrylate adsorbent spheres, and proteins washed out with 0.500 mol L-1KC1 solution were specific proteins imprinted by MIP resins. MIP resins with ARPCs had better recognition to the target proteins than that without ARPCs. The adsorption capacity of MIP resins immobilized ARPCs to the template BSA was about 80-100 μg g-1 when it was used for the adsorption of proteins mixture, and the specific adsorption of the target protein was obviously increased.

关键词： polyvinyl alcohol assistant recognition polymer chains molecular imprinting protein

One-way hash function based on hyper-chaotic cellular neural network

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Chinese Physics B 2008年第7期17卷 2388-2393页

作者：杨群亭高铁杠 College of Software Nankai University

The design of an efficient one-way hash function with good performance is a hot spot in modern cryptography researches. In this paper, a hash function construction method based on cell neural network with hyper-chaos characteristics is proposed. First, the chaos sequence is gotten by iterating cellular neural network with Runge Kutta algorithm, and then the chaos sequence is iterated with the message. The hash code is obtained through the corre- sponding transform of the latter chaos sequence. Simulation and analysis demonstrate that the new method has the merit of convenience, high sensitivity to initial values, good hash performance, especially the strong stability.

关键词： one-way hash function hyper-chaos cellular neural network Runge Kutta formula

Synthesis of MgO-doped ordered mesoporous carbons by Mg^(2+)-tannin coordination for efficient isomerization of glucose to fructose

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Green Energy & Environment 2023年第3期8卷 842-851页

作者： Junyan Fu Feng Shen Xiaoning Liu Xinhua Qi College of Environmental science and Engineering Nankai UniversityNo.38Tongyan RoadJinnan DistrictTianjin300350China Agro-Environmental Protection Institute Ministry of Agriculture and Rural AffairsNo.31Fukang RoadNankai DistrictTianjin300191China

In-situ MgO-doped ordered mesoporous carbon(OMC@MgO)was fabricated by formaldehyde-free self-assembly method,in which biomass-derived tannin was used as carbon precursor replacing fossil-based phenolics,Mg^(2+)as both cross-linker and precursor of catalytic *** to~20 wt% MgO could be doped in the carbon skeleton with good dispersion retaining well-ordered mesoporous structures,while more MgO content(35 wt%)led to the failing in the formation of ordered mesoporous *** OMC@MgO possessed a high specific surface area(298.8 m^(2) g^(-1)),uniform pore size distribution(4.8 nm)and small crystallite size of MgO(1.73 nm)due to the confinement effect of ordered mesoporous *** OMC@MgO as the heterogeneous catalyst,a maximum fructose yield of 32.4% with a selectivity up to 81.1%was achieved from glucose in water(90℃,60 min),which is much higher than that obtained using the MgO doped active carbon via conventional post-impregnation method(26.5%yield with 58.3% selectivity).Higher reaction temperature(>90℃)resulted in decrease of selectivity due to the formation of *** designed OMC@MgO displayed tolerant to high initial glucose concentrations(10 wt%)and could remain good recyclability without significant loss of activity for three cycles.

关键词： Glucose Fructose Isomerization Porous carbon Biomass Catalysis

Quantifying public health benefits of environmental strategy of PM2.5 air quality management in Beijing–tianjin–Hebei region,China

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Journal of Environmental sciences 2017年第7期29卷 33-40页

作者： Li Chen Mengshuang Shi Suhuan Li Shuang Gao Hui Zhang Yanling Sun Jian Mao Zhipeng Bai Zhongliang Wang Jiang Zhou College of Urban and Environmental science Tianjin Normal UniversityTianjin 300387China Chinese Research Academy of Environmental sciences Beijing 100012China

In 2013,China issued ＂Air Pollution Prevention and Control Action Plan（Action Plan）＂ to improve air *** assess the benefits of this program in Beijing-tianjin-Hebei（BTH）region,where the density of population and emissions vary greatly,we simulated the air quality benefit based on Ben MAP to satisfy the Action *** this study,we estimate PM_（2.5） concentration using Voronoi spatial interpolation method on a grid with a spatial resolution of 1 × 1 km^*** with the exposure-response function between PM_（2.5） concentration and health endpoints,health effects of PM_（2.5） exposure are *** economic loss is assessed by using the willingness to pay（WTP） method and human capital（HC） *** the PM_（2.5） concentration falls by 25% in BTH and reached 60 μg/m^3 in Beijing,the avoiding deaths will be in the range of 3175 to 14051 based on different functions each *** the estimated mortality attributable to all causes,3117 annual deaths were due to lung cancer,1924 – 6318 annual deaths were due to cardiovascular,and343 – 1697 annual deaths were due to *** on WTP,the estimated monetary values for the avoided cases of all cause mortality,cardiovascular mortality,respiratory mortality and lung cancer ranged from 1110 to 29632,673 to 13325,120 to 3579,1091 to 6574 million yuan,*** on HC,the corresponding values for the avoided cases of these four mortalities were 267 to 1178,161 to 529,29 to 143 and 261 million yuan,respectively.

关键词： BenMAP Air pollution Health benefits PM_(2.5) Beijing–tianjin–Hebei

Direct demonstration of triplet excimer in purely organic room temperature phosphorescence through rational molecular design

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Light(science & Applications) 2022年第6期11卷 1218-1226页

作者： Zhenjiang Liu Yu Tian Jie Yang Aisen Li Yunsheng Wang Jia Ren Manman Fang Ben Zhong Tang Zhen Li Institute of Molecular Aggregation science Tianjin UniversityTianjin 300072China Joint School of National University of Singapore Tianjin UniversityInternational Campus of Tianjin UniversityBinhai New CityFuzhou 350207China Shenzhen Institute of Molecular Aggregate science and Engineering School of Science and EngineeringThe Chinese University of Hong KongShenzhenGuangdong 518172China tianjin Key Laboratory of Molecular Optoelectronic sciences Department of ChemistryTianjin UniversityTianjin 300072China Department of Chemistry Wuhan UniversityWuhan 430072China Wuhan National Laboratory for Optoelectronics Huazhong University of Science and TechnologyWuhan 430074China

Organic luminogens with room temperature phosphorescence(RTP)have been paid great attention and developed rapidly for their wide application *** now,the internal mechanism and source of phosphorescence are still obscure,especially for the relationship between molecular dimer and RTP ***,we designed and synthesized eight phenothiazine 5,5-dioxide derivatives to directly reveal how the monomer and dimer in packing affect the RTP *** with strongπ-πstacking(θ<20.66°;d<3.86A)lead to pure triplet excimer emission,while those with weakπ-πstacking(27.02°<θ<40.64°;3.84A

关键词： RTP excimer rational