CHINESE JOURNAL OF CHEMICAL ENGINEERING
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2020
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IF 2.627
Guohao Du,Jianfeng Hu,Jianhui Zhou,Guangwu Wang,Shengli Guan,Hailing Liu,Man Geng,Chuang Lü,Yaoqiang Ming,Jinqing Qu
The self-healing microcapsules can be buried in the coating to improve the anticorrosive ability. In this paper, self-healing microcapsules of polyurea (PU)/melamine resin (MF) double shell were prepared by in-situ polymerization and interfacial polymerization with isocyanate as the core material. Scanning electron microscope was used to observe the microcapsule morphology. The structures of microcapsules prepared with different chain extenders were characterized by Fourier transform infrared spectroscopy . The micromanipulation system was used to loading–holding, loading–unloading and loading to rupture individual microcapsules, so as to explore the mechanical properties of microcapsules. The Young's modulus corresponding to microcapsules was calculated by mathematical model fitting. The self-healing properties of microcapsule coating were characterized by optical microscope . The experimental results showed that the microcapsule shell prepared under optimized conditions had a complete morphology and good mechanical properties . The microcapsule was in the elastic deformation stage under small deformation , and the plastic deformation stage under large deformation . The Young's modulus range of microcapsules was 9.29–14.51 MPa, and the corresponding Young's modulus could be prepared by adjusting the process. The surface crack of the coating containing microcapsule could heal itself after 48 h in a humid environment .
研究领域:
材料科学
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化学工程
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DOI
高影响因子
JOURNAL OF CHROMATOGRAPHY A
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2019
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IF 3.858
Linling Yu,Qiuhong Zhai,Yan Sun
Our previous studies on protein adsorption to the anion-exchangers of poly(ethylenimine) (PEI)-grafted Sepharose FF found that both adsorption capacity and uptake rate of bovine serum albumin (BSA) increased greatly when the PEI grafting density reached over a critical ionic capacity (cIC) due to the 3D protein binding and occurrence of “chain delivery” of bound proteins. Moreover, by the investigation on the anion-exchangers of diethylaminoethyl (DEAE)-modified and DEAE-dextran-grafted Sepharose FF, we found the unique role of surface ligand in facilitating protein uptake kinetics on dextran-functionalized anion exchangers as the “transfer station” for the “chain delivery” of bound proteins. However, what would be the contribution of surface ligands on the transport of bound proteins on PEI chains at a wide range across cIC, particularly at the lower IC range where no “chain delivery” was present? We have thus designed this research to answer the question. To this purpose, we fabricated three series of PEI-Sepharose FF resins, one without surface ligand (i.e., FF-PEI) and two with surface DEAE modifications at DEAE coupling densities of 60 and 90 mmol/L (i.e., FF-D60-PEI and FF-D90-PEI), and focused on the role of surface DEAE at different PEI densities in BSA adsorption equilibrium and uptake kinetics in a wide IC range of PEI across cIC (∼600 mmol/L for BSA). It was found that, at low grafting-ligand densities (IC cIC, however, both adsorption capacity and uptake rate changed only slightly (<5% and <10%, respectively) by the addition of surface DEAE groups. The results revealed that at IC < cIC, the surface DEAE groups provided the supplement of available binding sites and facilitated the happenings of the “chain delivery” of bound proteins as the “transfer station”, both of which were limited at the low IC range. However, at IC > cIC, the extended flexible PEI chains have already afforded 3D binding space with high accessibility and easy happening of “chain delivery” of bound proteins, so the surface DEAE groups between neighboring PEI chains did not work in assisting the transport of bound proteins. Moreover, when the IC was lower but close to the cIC, the FF-D-PEI resins exhibited higher uptake rates than FF-PEI resins at a similar or even lower IC values. These findings indicate that surface modification of charged groups in PEI-based anion exchangers of low grafting density would be an efficient strategy to fabricate high performance protein ion exchangers.
研究领域:
生物化学
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分离科学
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蛋白质工程
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DOI
高影响因子
JOURNAL OF MOLECULAR LIQUIDS
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2021
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IF 6.165
Helin Xu,Xueqin Li,Yanyan Hao,Xiaoqing Xu,Yan Zhang,Jinli Zhang
Acteoside (ACT) is a bioactive component, which has potential applications in the fields of food, health care, medicine, etc. The development of adsorbents that can efficiently and selectively adsorb ACT is still challenging. Here, polyethyleneimine (PEI) modified heterostructure porous polymer microspheres (HPPM@PEI) were designed and synthesized via a double emulsion interfacial polymerization strategy for efficient adsorption of ACT. HPPM@PEI possessed porous structure with a large pore volume of 1.58 m 3 /g, and PEI moiety was identified on the interior pores and external surface of the microspheres. PEI played two significant roles in the adsorption performance of HPPM@PEI. First, the introduced PEI increased pore volume and specific surface area of HPPM@PEI to provide more adsorption sites. Second, the PEI on interior pores and external surface allowed pH to regulate adsorption capacity and selectivity for ACT on [email protected] /600/2g. The experimental results indicated that [email protected] /600/2g exhibited the highest adsorption capacity of 138.26 ± 8.7 mg/g and selectivity of 6.01 ± 0.16. The adsorption process of ACT can be fitted by pseudo-second-order kinetic and Langmuir isotherm models. The adsorption mechanisms proposed that electrostatic attraction, hydrogen bonding, π-π stacking, and van del Waals were the main interaction forces between [email protected] /600/2g and ACT. This work proposes a novel strategy to synthesize polymer microspheres with large pore volume and high specific surface area for efficient adsorption of bioactive components from plants.
研究领域:
材料科学
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生物化学
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药物开发
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DOI
高影响因子
TALANTA
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2012
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IF 3.794
Qin Liu,Xu Zhu,Zhaohui Huo,Xulun He,Yong Liang,Maotian Xu
Graphene (GR) was synthesized through electrochemical reduction of graphene oxide and characterized by spectroscopic and electrochemical techniques. Polyvinylpyrrolidone (PVP)/graphene modified glassy carbon electrode (PVP/GR/GCE) was prepared and applied for the fabrication of dopamine (DA) sensors without the interference of ascorbic acid (AA). Compared to bare GCE, an increase of current signal was observed, demonstrating that PVP/GR/GCE exhibited favorable electron transfer kinetics and electrocatalytic activity towards the oxidation of dopamine. Furthermore, PVP/GR/GCE exhibited good ability to suppress the background current from large excess ascorbic acid. Amperometric response results show that the PVP based sensor displayed a wide linear range of 5×10 −10 to 1.13×10 −3 mol/L DA with a correlation coefficient of 0.9990 and a detection limit of 0.2 nM (S/N=3). The determination of dopamine in urine and human serum samples were studied.
研究领域:
分析化学
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生物医学工程
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DOI
高影响因子
COMPOSITES SCIENCE AND TECHNOLOGY
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2015
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IF 3.569
Liang Zhang,Shuai Yuan,Shuo Chen,Dongrui Wang,Bao-Zhong Han,Zhi-Min Dang
Ag nanoparticles@polydopamine (AgNPs@PDA) core–shell particles were prepared by one-step oxidative–reductive reaction, which Ag + was used as oxidant and dopamine as reducing agent. The dopamine was polymerized to PDA surface and shielded the Ag nanoparticles . The AgNPs@PDA particles were used as fillers and introduced into poly(vinylidene difluoride) (PVDF) to prepare the AgNPs@PDA/PVDF dielectric composites. AgNPs were introduced aiming to increase the dielectric constant of the composites and PDA was employed to improve the compatibility between fillers and polymer. The morphology and the dielectric properties of the AgNPs@PDA/PVDF composite films were thoroughly investigated. The influencing factors to the dielectric performances of the composites were studied, including the ratio of AgNO 3 and dopamine, pH values of the preparing solution and the fraction of the fillers. The highest dielectric constant of the AgNPs@PDA/PVDF composites was about 53 when the content of fillers was 25 wt.% at 100 Hz. The percolation threshold of the composites was predicted at about 25.5 wt.%.
研究领域:
材料科学
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化学工程
✓ 已验证
DOI
高影响因子
POLYMER COMPOSITES
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2021
·Vol. 42
·期 9
·4775-4785
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IF 3.171
Lu Shen,Xueqin Zhang,Yanzhou Lei,Mei Liang,Yang Chen,Wenbin Chen,Huawei Zou
For improving the mechanical properties of epoxy resin (EP), it is an effective strategy to utilize surface-modified graphene oxide (GO) as a reinforcement. However, there is nearly no report on surface modification using rigid short-chain grafted GO, especially with multiple reactive sites. In this work, a novel surface functionalization of GO with an amine-rich rigid short-chain was successfully prepared and applied as a filler for EP with simultaneously high toughness and mechanical strength. Superior toughness and mechanical strength of the resultant epoxy nanocomposite can be obtained by grafting amine-rich rigid short-chain onto GO (DHN-GO) owing to the enhanced interface binding ability with the EP and the optimized dispersibility in the matrix. Compared with the pure EP, the epoxy nanocomposites at an extremely low loading (0.75 wt‰) of DHN-GO showed excellent mechanical properties. The tensile strength, elongation at break, and bending strength are increased by 28%, 37%, and 29%, respectively. This work is expected to provide more inspiration for the preparation of GO/EP composites with high toughness and mechanical strength.
研究领域:
材料科学
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化学工程
✓ 已验证
DOI
高影响因子
DYES AND PIGMENTS
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2020
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IF 4.613
Tiechen Yu,Yuntao Han,Hongyan Yao,Zheng Chen,Shaowei Guan
In recent years, colorless-to-black electrochromic (EC) and electrofluorochromic (EFC) materials are attracting increasing interest for the fundamental scientific research and potential applications. In order to achieve multiple-response optoelectronic materials with better black conversion and solid-state fluorescence performance (black-color/emission dual-switchable materials), we adopted a novel design strategy to synthesis a diamine monomer named TPE-NH 2, in which the π-core tetraphenylethene (TPE) connects with two oxidation centers. All the polyamides/polyimides based on this monomer exhibited good solubility, thermal stability and aggregation-induced emission (AIE) activity. Among these, polyamide 5a not only showed rare EC properties (colorless-to-black) with ultra-low voltage (0–0.75 V), high optical contrasts (up to 87.9% at 692 nm) and fast switching times (2.04/1.45 s) but also demonstrated high fluorescence properties with the introduction of TPE. In addition, polyamide 5a showed good continuous switching stability for EC property and acceptable stability for EFC property, which makes it a potential candidate in EC/EFC applications.
研究领域:
材料科学
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光学工程
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DOI
高影响因子
ACS Sustainable Chemistry & Engineering
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2020
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IF 7.632
Zain Ali Saleh Bairq,Hongxia Gao,Fatima Abduh Mohammed Murshed,Paitoon Tontiwachwuthikul,Zhiwu Liang
In the CO2 capture process, decreasing the energy consumption and increasing the desorption rate of loaded MEA-CO2 during the regeneration process of monoethanol amine have been identified as major challenges that need to be addressed. To overcome these challenges, three modified heterogeneous mesoporous catalysts, CMK-3-SiO2, CMK-3-MCM-41, and CMK-3-SBA-15, and a SO42–/ZrO2 solid acid catalyst were initially synthesized and investigated to determine their catalytic effectiveness in the process of CO2 and MEA solvent regeneration with a CO2 loading of 0.5 ± 0.02 mol CO2/mol MEA at 97 °C. According to the experimental results, the CMK-3-modified catalyst significantly decreased the energy requirement for CO2 desorption. The catalytic performance of the synthesized catalysts was in the order of CMK-3-SiO2 > CMK-3-MCM-41 > CMK-3-SBA-15 > SZ. CMK-3-SiO2 exhibited the best catalytic performance by enhancing the desorption rate by 195%, and decreasing the energy requirement by 37.41% compared to monoethanol amine as a blank run. Furthermore, the CMK-3-SiO2 catalyst exhibited the best catalytic performance compared to the literature with excellent stability and no unfavorable effects on the MEA-CO2 absorption activity for the regenerated amine solvent. This performance seems to be a result of the large mesoporous surface area (BET) and the large number of Brϕnsted and Lewis acid sites. In addition, a reasonable reaction mechanism for amine solvent regeneration with the CMK-3 heterogeneous catalyst is proposed.
研究领域:
化学工程
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环境科学
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DOI
高影响因子
Journal of Cleaner Production
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2021
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IF 9.297
Yonghui Tu,Long-Fei Ren,Yuanxin Lin,H. Susan Zhou,Jiahui Shao,Yiliang He
The traditional adsorbents for antimonate (Sb(V)) in industrial effluent suffered from poor adsorption capacity due to the lack of pores or adsorption sites. Three-dimensional (3D) amidoxime-polyacrylonitrile sphere (APANS) with hierarchical pores and abundant amidoxime groups was fabricated via nanoscale thermally induced phase separation (TIPS). The effects of fabrication parameters including diluent type, PAN concentration and amidoximation time on pore structure were studied with scanning electron microscopy (SEM), mercury intrusion instrument (MIP), fourier transform infrared spectrophotometer (FT-IR) and X-ray photoelectron spectroscopy (XPS). Results showed that APANS fabricated from 2% PAN/DMSO solution and amidoximated for 20 min had coarse surface, numerous mesopores , high porosity (88.5%) and large pore volume (20.5 mL/g). The pore formation mechanism revealed that the hierarchical pores were derived from multiscale DMSO crystals shaped by TIPS. Adsorption kinetics results showed that kinetics data were well fitted by pseudo-second-order model ( R 2 > 0.99) and the mesopores accelerated the adsorption (equilibrium time of 4 h) due to enormous surface excess and group exposure. Adsorption isotherm could be modeled by Freundlich ( R 2 > 0.99) and maximum adsorption capacity was 683.6 mg/g. The adsorption thermodynamics was also investigated, indicating the spontaneous and exothermic adsorption process . APANS exhibited excellent selectivity towards common anions (Cl − , SO 4 2− , NO 3 − and PO 4 3− ) and reliable reusability (preserving 80% capacity after five cycles). This adsorbent provided a clean and sustainable strategy for Sb(V) removal from aqueous environment by superhigh capacity, fast rate and reliable reusability.
研究领域:
环境科学
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材料科学
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DOI
高影响因子
Energy Storage Materials
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2020
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IF 16.28
Yu-Shan Zhang,Bin-Mei Zhang,Yu-Xia Hu,Jun Li,Chun Lu,Ming-Jin Liu,Kuangye Wang,Ling-Bin Kong,Chen-Zi Zhao,Wen-Jun Niu,Wen-Wu Liu,Kun Zhao,Mao-Cheng Liu,Yu-Lun Chueh
Graphite has been commercialized as a material of lithium ions batteries because of its abundant source, low cost and excellent conductivity while the small interlayer spacing of graphite limits its application for Na + insertion/extraction. Herein, an emerging and effective approach—chain-like H 2 N(CH 2 ) x NH 2 locked between graphene oxide (GO) sheets to expand the interlayer spacing of graphene with enhanced stability of layered structure was demonstrated by a dehydration condensation reaction . The as-obtained H 2 N(CH 2 ) x NH 2 , which can link GO (xDM-GO), exhibits a lock-link structure, resulting in expanded interlayer spacing, with which the excellent Na + storage performance with a high specific discharge capacity of 158.1 mAh g −1 at 0.1 A g −1 and outstanding capacity retention of 82.2% at a current density of 1 A g −1 can be achieved. The effects of interlayer spacing on Na + diffusion coefficient and the rate capability were investigated, for which 0.95 nm is the most suitable interlayer spacing for the Na + insertion/extraction. The novel strategy demonstrates an effective way to controllably tune the interlayer spacing with the improved structure stability of GO, resulting in the best Na + insertion/extraction behavior with the excellent Na + storage performance.
研究领域:
材料科学
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能源存储
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DOI
高影响因子
SEPARATION AND PURIFICATION TECHNOLOGY
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2022
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IF 9.136
Yuyang Yao,Junjie Mu,Junbin Liao,Jun Dong,Bin Luo,Huimin Ruan,Zhenlu Shen,Jiangnan Shen
In this work, a series of modified anion exchange membranes (AEMs) has been prepared via self-polymerization of L-dopa on the surface of commercial AEM (Fuji I type), followed by grafting the 4-amino-benzenesulfonic acid monosodium salt (ABS) on L-polydopamine thin layer. The chemical structures of modified AEMs were confirmed by the FTIR and XPS spectra. Our investigation demonstrates that the surface resistance of the modified AEM (L-PDA@ABS-Cl) increases slightly from 1.90 Ω cm 2 to 2.37 Ω cm 2 and the hydrophilicity of L-PDA@ABS-Cl significantly improves, verifying by the decreased water contact angles from 86.42° to 67.25°. The difference between pristine AEM and L-PDA@ABS-Cl in desalination rates only remained less than 4% throughout the test of 240 min. The modified AEMs have the negatively charged functional layers which produce an electrostatic repulsion effect and negatively charged bacteria cannot attach to the membrane surface. As a result, L-PDA@ABS-Cl shows good performance on fouling resistance, good inhibition effect on Escherichia coli ( E. coli ) and Staphylococcus aureus ( S. aureus ). Low surface resistance and superior foul inhibition performance indicate the potential application of modified AEMs in electrodialysis (ED).
研究领域:
材料科学
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环境工程
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生物医学
✓ 已验证
DOI
高影响因子
SENSORS AND ACTUATORS B-CHEMICAL
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2021
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IF 7.46
Xueyan Liu,Zhuo Chen,Rongsheng Gao,Chengyou Kan,Jianhong Xu
Recently, the colorimetric quantitative method based on a smartphone and red–green–blue (RGB) analysis is applied to provide rapid on-site monitoring of metal ions. To develop such a fluorescent and colorimetric chemosensor for Fe 3+ , the functionalized polyacrylamide hydrogel P(AM- co -MBA- co -RhBUEA) was synthesized by free radical polymerization on the basis of a rhodamine-based probe RhBUEA. The physicochemical properties and sensing behavior of the functionalized hydrogel were investigated by FTIR, SEM and fluorescence spectral analysis. And the effects of MBA and RhBUEA amount on gel content and swelling properties were explored. According to the recipe of 1.0 wt.% MBA, 2.0 wt.% RhBUEA to the total monomers, the fabricated hydrogel displayed excellent selectivity, sensitivity and reversibility for Fe 3+ sensing in the pH range of 4.95–8.02, with the detection limit of 0.088 μM for the fluorescent quantitative method and the response time less than 20 min, accompanied with a distinct color change. Owing to the integration of RGB analysis with colorimetric responses, the functionalized hydrogel permitted the convenient, simplified and rapid colorimetric quantitative detection of Fe 3+ with the detection limit of 1.1 μM, which avoids the need of sophisticated instruments and trained operators.
研究领域:
分析化学
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环境科学
✓ 已验证
DOI
高影响因子
危险品化学品经营许可证（带存储）