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Anionic structural effect in liquid–liquid separation of phenol from model oil by choline carboxylate ionic liquids

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Green Energy & Environment 2019年第2期4卷 131-138页

作者： Zhiyong Li Ruipeng Li Xiaoqing Yuan Yuanchao Pei Yuling Zhao Huiyong Wang Jianji Wang Collaborative Innovation Center of Henan Province for Green Manufacturing of Fine chemicals Key Laboratory of Green Chemical Media and ReactionsMinistry of Education School of Chemistry and Chemical Engineering Henan Normal University Henan Key Laboratory of Green Chemistry Henan Normal University

Phenolic compounds exist in crude oil as pollutants, and their removal is vital important for the refining and further application of oils. In traditional separation approaches, strong acid and strong base have to be used to remove these compounds, which may cause serious environmental problems. In this work, 19 kinds of cholinium ionic liquids have been developed to separate phenol from model oil by liquid–liquid extraction. Structural effect of anions of the ionic liquids in the separation is systematically investigated. It is found that depending on the chemical structure of ionic liquids, phenol can be removed from toluene with single-step removal efficiency from 86 to 99% under optimal conditions. The type of substituent groups and the-CH_2 number between two carboxylates have obvious effect on the removal efficiency, and more hydrophilic ionic liquids have a stronger extraction performance for phenol. Furthermore, thermodynamic,^(13) C NMR,~1 H NMR and density functional theory calculations have been performed to characterize the extraction process and to understand the extraction mechanism. It is shown that the extraction of phenol from oil to ionic liquid is a favorable process, and this process is mainly driven by enthalpy change. The formation of the hydrogen bond between anion of the ionic liquid and-OH of phenol is the main driving force for the extraction of phenol from oil to the ionic liquids.

关键词： Ionic liquid Extraction Phenol Choline Hydrogen bonding

Application of ^(14)N(d,α)^(12)C Nuclear Reaction to the Concentration Analysis of Nitrogen in Iron Meteorites

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Chinese Physics Letters 1995年第5期12卷 265-268页

作者： HU Beilai A.L.Hanson K.W.Jones Department of Physics Nankai UniversityTianjin 300071 Brookhaven National Laboratory UptonNew York 11973U.S.A.

The ^(14)N(d,α)^(12)C nuclear reaction has been used to measure the nitrogen content in iron *** analysis was made with 2.0MeV^(2)H^(+) beam from Brookhaven 3.5MV research electrostatic *** detection limits of about ... 详细信息

关键词： electrostatic beam

Selective Dealkenylative Functionalization of Styrenes via C-C Bond Cleavage

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Research 2020年第1期2020卷 1420-1428页

作者： Jianzhong Liu Jun Pan Xiao Luo Xu Qiu Cheng Zhang Ning Jiao State Key Laboratory of Natural and Biomimetic Drugs Peking University100191 BeijingChina State Key Laboratory of Organometallic Chemistry Chinese Academy of SciencesShanghai 200032China

As a readily available feedstock,styrene with about 25 million tons of global annual production serves as an important building block and organic synthon for the synthesis of fine chemicals,polystyrene plastics,and ***,in the past decades,many direct transformations of this costless styrene feedstock were disclosed for the preparation of high-value chemicals,which to date,generally performed on the functionalization of styrenes through the allylic C-H bond,C(sp2)-H bond,or the C=C double bond ***,the dealkenylative functionalization of styrenes via the direct C-C single bond cleavage is so far challenging and still ***,we report the novel and efficient C-C amination and hydroxylation reactions of styrenes for the synthesis of valuable aryl amines and phenols via the site-selective C(Ar)-C(alkenyl)single bond *** chemistry unlocks the new transformation and application of the styrene feedstock and provides an efficient protocol for the late-stage modification of substituted styrenes with the site-directed dealkenylative amination and hydroxylation.

关键词： styrene cleavage synthesis

Soft template synthesis of high selectivity mesoporous SnO_2 gas sensors

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Journal of Shanghai University(English Edition) 2010年第4期14卷 297-300页

作者：刘刚谈志金王丛吴若飞张海娇 School of Environmental and chemical Engineering Shanghai University

Mesoporous SnO2 was synthesized using cetyltrimethyl ammonium bromide （CTAB） as supermolecule-template by hydrothermal method followed by calcining under different temperature in air. X-ray diffraction analysis （XRD） and transmission electron microscopy （TEM） techniques were used to characterize the structure of mesoporous SnO2. The results indicated that the gas sensors prepared by using mesoporous SnO2 after calcination at 400 ℃ showed quick response and recovery to ethanol at 200 ℃. It was also found that the mesostructure SnO2 with small particle size had higher sensitivity and selectivity to C2HhOH than the SnO2 nanoparticles the particle size of which is 20 nm synthesized by sol-gel method.

关键词： tin dioxide mesoporous nanostructure cetyltrimethyl ammonium bromide (CTAB) gas sensing properties

Mass transport mechanisms within pervaporation membranes

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Frontiers of chemical Science and Engineering 2019年第3期13卷 458-474页

作者： Yimeng Song Fusheng Pan Ying Li Kaidong Quan Zhongyi Jiang Key Laboratory for Green chemical Technology School of Chemical Engineering and TechnologyTianjin UniversityTianjin 300350China Collaborative Innovation Center of chemical Science and Engineering (Tianjin) Tianjin 300072China

Pervaporation is an energy-efficient membrane technology for separating liquid molecules of similar physical properties, which may compete or combine with distillation separation technology in a number of applications. With the rapid development of new membrane materials, the pervaporation performance was significantly improved. Fundamental understanding of the mass transport mechanisms is crucial for the rational design of membrane materials and efficient intensification of pervaporation process. Based on the interactions between permeate molecules and membranes, this review focuses on two categories of mass transport mechanisms within pervaporation membranes: physical mechanism (solutiondiffusion mechanism, molecular sieving mechanism) and chemical mechanism (facilitated transport mechanism). Furthermore, the optimal integration and evolution of different mass transport mechanisms are briefly introduced. Material selection and relevant applications are highlighted under the guidance of mass transport mechanisms. Finally, the current challenges and future perspectives are tentatively identified.

关键词： pervaporation membrane mass transport mechanisms physical mechanism chemical mechanism

Fluorescence-resonance energy transfer(FRET)within the fluorescent metallacycles

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Chinese chemical Letters 2020年第11期31卷 2884-2890页

作者： Qinghui Ling Tanyu Cheng Shaoying Tan Junhai Huang Lin Xu Shanghai Key Laboratory of Green Chemistry and chemical processes School of Chemistry and Molecular EngineeringEast China Normal UniversityShanghai 200062China Key Laboratory of Resource Chemistry of Ministry of Education Shanghai Key Laboratory of Rare Earth Functional MaterialsShanghai Normal UniversityShanghai 200234China State Key Laboratory of New Drug and Pharmaceutical Process Shanghai Institute of Pharmaceutical IndustryChina State Institute of Pharmaceutical IndustryShanghai 201203China State Key Laboratory of Fine chemicals Dalian University of TechnologyDalian 116024China

During past few years,the construction of fluorescent metallacycles featuring the fluorescenceresonance energy transfer behavior has attracted extensive attention due to their diverse applications such as real-time monitoring the dynamics of coordination-driven self-assembly,photoswitching fluorescence-resonance energy transfer,and light-controlled generation of singlet oxygen for cancer *** review focuses on the recent advances on the design principles,preparation methods,optical properties,and the wide applications of fluorescent metallacycles with the FRET property.

关键词： Fluorescence-resonance energy transfer Coordination-driven self-assembly Metallacycle Fluorescent material Supramolecular chemistry

A new paleoenvironmental index for anoxic events—Mo isotopes in black shales from Upper Yangtze marine sediments

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Science China Earth Sciences 2011年第7期54卷 1024-1033页

作者： ZHOU Lian SU Jie HUANG JunHua YAN JiaXing XIE XiNong GAO Shan DAI MengNing Tonger State Key Laboratory of Geological processes and Mineral Resources China University ofGeosciences Wuhan 430074 China Key Laboratory of Biogeology and Environmental Geology of Ministry of Education China University of Geosciences Wuhan 430074 China Key Laboratory of Tectonics and Petroleum Resources of Ministry of Education China University of Geosciences Wuhan 430074 China State Key Laboratory of Continental Dynamics Department of Geology Northwest University Xi'an 710069 China Wuxi Institute of Petroleum Geology China Petroleum & Chemical Corporation Wuxi 214151 China

This paper investigates the high-solution of Mo isotopes and uses trace-element analyses for fresh and representative black shales and siliceous shales collected from the transition between the Late Ordovician and the Early Silurian at the Wangjiawan section in Yichang and the Late Permian Dalong Formation in the Shangsi Section of Sichuan. The applicability of different geochemical parameters used as paleo-oxygenation indices are also compared. The preliminary results show that V/（V＋Ni）, Uauth （auth U）, V/Cr, Ceanom and U/Th have a scattered variation range, but most samples plot within the suboxic-anoxic fields. The suboxic-anoxic environment was dominant during the deposition and formation of the two anoxic facies. These redox indicators show little correspondence to the δ98M0 values. The U/Mo ratio can be used as a potential proxy for the paleo-redox conditions due to the possibility that Mo is enriched relative to U at different redox gradients during early diagenesis. This evidence is more significant for the euxinicity condition and corresponds to positive δ98M0 （〉1.5%o） values with low U/Mo ratios. This evidence is likely related to the depositional conditions near the boundary between anoxic and euxinic environ- ments, which are characterised by low bioturbation or water circulation. Other samples reveal a wide scatter of U/Mo ratios and δ98M0 〈1.5%0. These results are likely due to punctuated improvements in oxygenation with intense bioturbation or water circulation, which led to the redistribution of trace element.

关键词： molybdenum isotopes proxy for paleo-redox conditions black shale Upper Yangtze

Experimental and computational studies on flow behavior of gas-solid fluidized bed with disparately sized binary particles

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Particuology 2008年第2期6卷 59-71页

作者： Jinsen Gao Jian Chang Chunxi Lu Chunming Xu State Key Laboratory of Heavy Oil Processing China University of Petroleum Changping Beijing 102249 China

This paper presents experimental and computational studies on the flow behavior of a gas-solid fluidized bed with disparately sized binary particle mixtures. The mixing/segregation behavior and segregation efficiency of the small and large particles are investigated experimentally. Particle composition and operating conditions that influence the fluidization behavior of mixing/segregation are examined. Based on the granular kinetics theory, a multi-fluid CFD model has been developed and verified against the experimental results. The simulation results are in reasonable agreement with experimental data. The results showed that the smaller particles are found near the bed surface while the larger particles tend to settle down to the bed bottom in turbulent fluidized bed. However, complete segregation of the binary particles does not occur in the gas velocity range of 0.695-0.904 m/s. Segregation efficiency increases with increasing gas velocity and mean residence time of the binary particles, but decreases with increasing the small particle concentration. The calculated results also show that the small particles move downward in the wall region and upward in the core. Due to the effect of large particles on the movement of small particles, the small particles present a more turbulent velocity profile in the dense phase than that in the dilute phase.

关键词： Binary particles Distinct size difference Mixing Segregation Fluidized bed CFD

Determination of Parathion-methyl in Vegetables by Fluorescent-Labeled Molecular Imprinted Polymer

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Chinese Journal of Chemistry 2011年第10期29卷 2134-2140页

作者：孙倩姚倩倩孙琳周天舒聂冬霞施国跃金利通 Department of Chemistry and Shanghai Key Laboratory of Green Chemistry and chemical Process East China Normal University 3663 Zhongshan Road （N） Shanghai 200062 China Department of Environmental Science East China Normal University 3663 Zhongshan Road （N） Shanghai 200062 China

A novel sensor for the determination of parathion-methyl based on couple grafting of functional molecular imprinted polymers （MIPs） was fabricated which is developed by anchoring the MIP layer on surfaces of silica particles embedded CdSe quantum dots by surface imprinting technology. The synthesized molecular imprinted silica nanospheres （CdSe@SiO2@MIP） allow a high selectivity and sensitivity of parathion-methyl via fluorescence intensity decreasing when the MIP material rebinding the parathion-methyl molecule. Compared with the MIP fabri- cated in traditional method, the template of parathion-methyl was easier to remove from the CdSe@SiO2@MIP imprinted material. Under optimal conditions, the fluorescence intensity of parathion-methyl at the imprinted sensor was detected by spectrofluorophotometer. The relative fluorescence intensity of CdSe@SiO2@MIP decreased linearly with the increasing concentration of parathion-methyl ranging from 0.013 mg·kg^-1 to 2.63mg·kg^-1 with a detection limit （3σ） of 0.004 mg·kg^-1 （S/N=3）, which is lower than the MIP in tradition. The imprinted film sensor was applied to detect parathion-methyl in vegetable samples without the interference of other organophosphate pesticides and showed a prosperous application in the field of food safety.

关键词： parathion-methyl quantum dots fluorescence molecular imprinted silica particles