JOURNAL OF APPLIED POLYMER SCIENCE
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2014
·Vol. 131
·期 13
·
IF 1.64
Yang Cao,Lukuan Liu,Wanzhen Xu,Xiangyang Wu,Weihong Huang
The preparation of indole molecularly imprinted polymers (indole-MIPs) using 4-vinylpyridine as functional monomer, silica gel as matrix were used to adsorb indole from fuel oil specifically. The reverse atom transfer radical polymerization (RATRP) technology was introduced to prepare the surface molecularly imprinted polymers, and the precipitation polymerization was adopted in the preparation process. The obtained indole-MIPs were characterized by nitrogen adsorption, Fourier transform infrared spectrometry and scanning electron microscopy. The results show that indole-MIPs were provided with the larger surface areas and more pores. The adsorption capacity of indole-MIPs was 31.80 mg g −1 at 298 K, and the adsorption equilibrium was reached in a short time. The adsorption process was spontaneous by thermodynamic analysis, and an appropriate decrease in temperature could enhance the adsorption capacity. The adsorption process obeyed pseudo-second-order kinetic model by kinetics analysis. The isotherm analysis results show that both Langmuir and Sips equations were suitable to experimental data. The selective adsorption and reusable performance of indole-MIPs were favorable. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014 , 131 , 40473.
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高影响因子
RESEARCH ON CHEMICAL INTERMEDIATES
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2014
·Vol. 41
·期 10
·7073-7093
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IF 1.54
Lv T. M.,Zhu S. H.,Guo L.,Zhang S. T.
The inhibiting effect of indole on the corrosion of mild steel Q235 in 0.1 M H 2 SO 4 was investigated through different approaches including weight loss, potentiodynamic polarization, electrochemical impedance spectroscopy (EIS), scanning electron microscope experiments, and theoretical calculations. Polarization curves reveal that the indole acts as a mixed-type inhibitor and the reaction mechanism in respect of either hydrogen evolution or mild steel dissolution has not been modified. EIS results imply that the water molecules adsorbed on the steel surface are substituted by the indole molecules and the inhibiting behavior of indole is probably due to the formation of an adsorptive film on the steel surface. Thus the thermodynamic and kinetic parameters are determined and discussed to give better understanding of the adsorption process. Theoretical calculations are also discussed in light of the optimized molecular structure of indole to gain further insight of the inhibition mechanism.
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高影响因子
CHEMICAL ENGINEERING JOURNAL
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2015
·
IF 4.321
Qian Yao,Lujiang Xu,Zheng Han,Ying Zhang
Furfural, an abundant biomass derived compound, was converted into indoles via thermo-catalytic conversion and ammonization with zeolites. The effect of reaction temperature, catalyst, weight hourly space velocity (WHSV) and ammonia to furfural molar ratio on the product distribution was investigated systematically. They all played important roles on indoles production. The maximal carbon yield of indoles (20.79%) was achieved by using HZSM-5 (Si/Al = 25) catalyst at 650 °C with WHSV as 1.0 h −1 and NH 3 to furfural molar ratio as 2. The HZSM-5 (Si/Al = 25) catalyst was recycled for five times and showed slight deactivation. Three possible aldehyde group of furfural conversion pathways were proposed and one possible reaction pathway from furfural to indoles was verified based on the experimental and quantum calculation results, that is, furfural firstly reacted with ammonia to form furfural-imine, and then furfural-imine underwent a cracking reaction to form furan. Thereafter, furan was converted to pyrrole and finally to indoles.
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高影响因子
POLYMERS FOR ADVANCED TECHNOLOGIES
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2015
·Vol. 26
·期 5
·476-486
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IF 1.757
Pengfei Ma,Wenming Yang,Ting Fan,Hong Liu,Zhiping Zhou,Jinhui Li,Lin Zhang,Wanzhen Xu
Multi-template molecular imprinting technique was employed for the theoretical study about industrial oil denitrification. Prior to the preparation of multi-template molecularly imprinted polymers (MT-MIPs), density functional theory was used for simulating the imprinted pre-assembly systems composed of template (aniline, indole, or 3-methylinndole) and monomer [methacrylic acid, acrylamide (AM), and 4-vinylpyridine]. MT-MIPs were synthesized as surface MIPs simply and successively by seeded emulsion polymerization or two-stage precipitation polymerization. The experimental results were consistent with the simulative results, which demonstrated that AM was more suitable monomer together. In addition, seeded emulsion polymerization synthesized MT-MIPs with better performance compared with two-stage precipitation polymerization. The adsorption kinetics and adsorption isotherm of MT-MIP prepared with AM using seeded emulsion polymerization were fitted with different models. The fitting results indicated that pseudo-second-order kinetics model and Freundlich isotherm model were suitable for describing the adsorption process of AM seeded emulsion polymerization. This study will provide a certain guidance and theoretical basis for introducing the combination of multi-template molecular imprinting technique and computational simulation into the field of industrial denitrification. Copyright © 2015 John Wiley & Sons, Ltd.
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高影响因子
RSC Advances
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2013
·Vol. 4
·期 2
·605-616
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IF 2.562
Lukuan Liu,Yang Cao,Pengfei Ma,Chunxiao Qiu,Wanzhen Xu,Hong Liu,Weihong Huang
Novel magnetic imprinted polymers are designed by molecular simulation from a comprehensive perspective and prepared rationally by combining the modified surface imprinting technique with the improved atom transfer radical polymerization. The simulation results show that interaction intensity between indole and monomers are simultaneously affected by complex conformation, charge transfer and binding energy. The optimal monomer for the removal of indole is AM and the best ratio is 1 : 4 in the studied three monomers. To verify the reliability and accuracy of the simulation results, three kinds of novel magnetic imprinted polymers are prepared with different monomers. The experimental results show that molecular simulation is reliable in processing the pre-assembled complexes of molecularly imprinted polymers (MIPs). The MIPs using AM as monomer display the highest selectivity (2.561) and bonding percentage (31.062%). Structural superiority of the optimal adsorbent is reflected by using several characterization methods. A series of static adsorption tests such as kinetic, isotherm and selectivity are used to analyse the adsorption performance. The test results show that the novel adsorbents conform to the Elovich kinetic equation and follow the Langmuir isotherm model. Meanwhile, they display higher selectivity towards indole than towards other analogues. The novel adsorbents have potential application value in the denitrogenation field.
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高影响因子
Polymer Chemistry
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2015
·Vol. 7
·期 4
·860-866
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IF 5.52
Hongyuan Wang,Rongqi Zhu,Po Yang,Yi Gu
The chain propagations of Bisphenol A-aniline benzoxazine (defined as BA-a) polymerized by thermal induction and in the presence of various catalysts or curing agents during the curing process before gelation were investigated in this paper. DSC, gel time test and GPC were used to measure the curing behavior, number-average molecular weight (n), glass transition temperature (Tg), gel time (tgel) and curing conversion (α) of different benzoxazine systems. By comparing the experimental results (n and Tg) with the models of step polymerizations and chain polymerizations proposed by Flory et al., three kinds of chain propagations of benzoxazine were observed and confirmed. The step polymerization occurred in the thermal induction or in the presence of catalyst N,N-dibenzylaniline (tAm), and then the non-living chain polymerization and the living chain polymerization occurred, respectively, when indole (Id) and other additives such as phenol (tBp), acid (HA), imidazole (IMZ) etc. were added to benzoxazine as catalysts or curing agents. Moreover, the relationship between the chain propagation and curing kinetics of benzoxazine was also established. The chain propagation of benzoxazine systems involves step polymerization, non-living chain polymerization andliving chain polymerization, the conversion of the gel point (αgel) is almost equal to, less than and greater than the value of the conversion at which the polymerization rate reaches a maximum (αmax), respectively. The results may contribute to a better understanding of the polymerization mechanism of benzoxazine and provide new approaches to effective control of the polymerization kinetics and growth crosslink structures of benzoxazine.
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高影响因子
RSC Advances
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2016
·Vol. 6
·期 74
·69909-69918
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IF 3.289
Wentong Song,Shengyang Tao,Yongxian Yu,Xuanlu Du,Shuo Wang
This article reports a facile synthetic approach for preparing magnetic porous catalysts, on which various inorganic compounds are alternately loaded using a pyrogallic acid (PG)-assisted layer-by-layer (LbL) coating. The PG forms an adhesion and reductive layer on the surface of hierarchically porous silica, and Pd, Al2O3, ZrO2, or FeOx can then be introduced on the surface of the material. Compared with the conventional impregnation method, the PG layer obviously improves the dispersion of catalysts and greatly reduces the blocking of the pores, which is caused by the formation of metal oxide catalysts. At the same time, the reduction properties of the layer help to reduce the diameter of the Pd nanoparticles to 5 ± 1.3 nm. The Fe3+ ions are partially reduced into Fe2+ by the PG layer to form Fe3O4, which endows the porous catalysts with a magnetic separation property. The synthesized multicomponent catalysts show excellent catalytic activity for various reactions, including the Suzuki Miyaura coupling, reduction, Knoevenagel condensation and Friedel–Crafts alkylation reactions. The TOF values show an improvement of 2 to 4 times over those of the catalysts prepared by the traditional impregnation method. The multicomponent magnetic catalysts also exhibit superior catalytic performance for many one-pot multistep cascade reactions.
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高影响因子
Molecular Catalysis
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2017
·
IF 0
Zhanao Lv,Haibin Wang,Zhuqi Chen,Shuhua Zou,Shuaishuai Zhu,Chenlin Lou,Guochuan Yin
Dioxygen activation as the solely terminal oxidant in organic synthesis and catalytic oxidation is particularly attractive from the point of economic and environmental view. In our previous study, we have displayed that the introducing of non-redox metal ions can sharply improve the olefin epoxidation catalyzed by ruthenium complex with PhI(OAc) 2 as the organic oxidation. Inspired by the successful strategy and dioxygen activation, in this study, we demonstrate an alternative protocol that adding non-redox metal ions to cis -Ru(bpy) 2 Cl 2 catalyst can remarkably improve the oxidation from Ru(II) to Ru(IV) = O with dioxygen as the oxidant and promote oxidative dehydrogenation of saturated C–C bond whereas Ru(bpy) 2 Cl 2 alone is very sluggish. Through UV–Vis, NMR, cyclic voltammogram and EPR characterization, it has been testified that oxidation from Ru(II) to Ru(IV) = O can be realized under the condition of 1 atm of dioxygen and 323 K within 25 min while extreme tough condition of 20 atm of dioxygen, 343 K and 8 h is necessary for Ru(bpy) 2 Cl 2 alone. Combined the reaction data with characterization results, an adduct of Ru(IV) = O/Sc(III) is proposed as the key active species to improve the catalytic efficiency. The activity improvement in oxidative dehydrogenation illustrated a novel strategy of that adding non-redox metal ions to sluggish catalysts can remarkably improve its efficiency for dehydrogenation of saturated C–C bond, especially through dioxygen as ultimate oxidant.
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Journal of the Taiwan Institute of Chemical Engineers
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2016
·
IF 2.848
Bin Jiang,Zhaohe Huang,Luhong Zhang,Yongli Sun,Huawei Yang,Hanrong Bi
In this work, several kinds of imidazolate-based ether-functionalized ionic liquids (ILs) were synthesized and used for CO 2 capture. It is note-worthy that IL with [C 6 O 2 mim] + as cation has much smaller molecular weight but similar mole capacity compared with those with [P 66614 ] + , which is usually used as cation for anion-functionalized ILs in the carbon capture process. Among these task functionalized ILs, [C 6 O 2 mim][4-Br-Im] can be a potential candidate for carbon capture. Not only has [C 6 O 2 mim][4-Br-Im] an extremely high CO 2 capacity (more than 1.60 mol CO 2 per mol IL achieved), but also shows high uptake efficiency and recovery capability. In addition, [C 6 O 2 mim][4-Br-Im] has higher thermal stability, higher water stability and lower absorption enthalpy. The mechanism of this carbon capture process was investigated by FT-IR and NMR spectroscopy. Surprisingly, in this process, CO 2 first bound the cations to form zwitterions. When CO 2 was continuously bubbled into ILs, the zwitterions started to dissociate and the anions combined with CO 2 . It is verified that this process is a carbon capture transforming process with the Cationic-drive transforming to Anionic-drive. This work offers a deep understanding of the combination process between CO 2 and imidazolate-based with aprotic heterocyclic anions.
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FOOD RESEARCH INTERNATIONAL
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2024
·
IF 7
Jie-Qiong Wang,Ying Gao,Zhi-Hui Feng,Si-Han Deng,Jian-Xin Chen,Fang Wang,Yi-Fan Li,Ying-Bin Zhang,Jun-Feng Yin,Liang Zeng,Wei-Biao Zhou,Yong-Quan Xu
The deterioration of aroma quality in tea beverages during the shelf life is a significant issue. In this study, sensomics techniques were employed to identify the characteristic factor contributing to aroma degradation in green tea infusion. Samples A (no/faint retort odor) and B (high intensity retort odor) were selected based on their retort-like odor intensity after heat treatment simulating shelf-life conditions. The key odorants were identified through a combination of chemometrics analysis, comparative aromatic extract dilution analysis (cAEDA), detection frequency analysis (DFA), and odor-specific magnitude estimation (OSME). Subsequently, eight odorants, including linalool (892.451 μg/L), ( E )- β -damascenone (5.105 μg/L), phenylacetaldehyde (27.720 μg/L), nonanal (2201.439 μg/L), α -terpineol (7.166 μg/L), geraniol (0.499 μg/L), theaspirane (0.044 μg/L), and 2-hydroxy-5-methylacetophenone (2.973 μg/L), were identified as the key substances contributing to the retort-like odor in sample B. Aroma recombination and omission test further demonstrated that elevated concentrations of nonanal, geraniol, phenylacetaldehyde, and theaspirane might be the primary reasons for the retort odor observed in samples.
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PubMed
高影响因子
FUEL
·
2017
·
IF 4.601
Youan Ji,Yucui Hou,Shuhang Ren,Muge Niu,Congfei Yao,Weize Wu
Indole plays a significant role in the production of products such as spices, medicines, and exogenous auxins. Deep eutectic solvents (DESs) formed by indole and quaternary ammonium salts (QASs, including tetraethylammonium chloride-TEAC, tetrapropylammonium chloride-TPAC, triethylmethyl-ammonium chloride-TEMAC) were found and proposed to efficiently extract indole from model wash oil. The effects of time, temperature, mole ratio of QAS to indole and initial indole concentration on the extraction of indole were studied. The results indicate that these QASs can extract indole from wash oil with efficiencies up to 96.7% (TPAC). The extraction process can be finished within 5 min. It is also found that the ultimate concentrations are almost identical for one kind of QAS although their initial concentrations are different, and the indole concentration in model wash oil can be reduced to a very low level of 1.3 g/dm 3 (TPAC). The maximum distribution coefficients of indole are 40.8 for TEAC, 91.9 for TPAC, and 29.5 for TEMAC at the studied conditions, and the extraction ability follows the order of TPAC > TEAC > TEMAC. Moreover, QASs in DESs can be reused without obvious reduction in extraction efficiency. The extraction mechanism was studied by FT-IR, and the results indicate that there is a hydrogen bond between QAS and indole. Finally, a comparison was made between this method and other methods to verify and demonstrate its desirable properties of efficiency and environmentally friendliness.
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APPLIED SURFACE SCIENCE
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2024
·
IF 6.3
Yanting Guo,Qing Li,Lu Zheng,Dandan Liu,Guangming Nie
A highly sensitive humidity sensor based on Ag doped polyindole/hydroxyethyl cellulose (Ag-PIn/HEC) composite is constructed for relative humidity sensing at room temperature in this study. Doping of Ag and HClO 4 is used to solve the problem of poor electrical conductivity of polyindole (PIn). The humidity sensitive material is prepared by the combination of HEC binder and doped PIn, which realizes the high sensitivity humidity detection. The Ag-PIn/HEC sensor showed high response value (93800 %), good linearity (R 2 = 0.993), fast response time (8 s), low humidity hysteresis (4.16 %), good reproducibility, and stability over a detection range of 11 ∼ 84 % relative humidity (RH). In addition, the humidity sensor has a specific response to human breath. According to the change of impedance signals, it can easily distinguish between oral and nasal breathing as well as light or rapid breathing, which can be used in medical care, such as preventive monitoring for special groups (asthma patients). Moreover, the sensor can recognize certain simple words by detecting changes in exhalation while speaking, which provides potential applications in speech recognition and non-contact switches.
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危险品化学品经营许可证（带存储）