CHEMOSPHERE
·
2022
·
IF 8.943
Liyun Zhang,Yi He,Pingya Luo,Lan Ma,Shuangshuang Li,Yiling Nie,Jing Yu,Xiao Guo
Considering the emulsified oil and water-soluble dyes in wastewater, the exploitation of easy-manufacturing, energy-saving and high-efficiency separation materials is urgently required. In this work, integrating the positively charged polyethyleneimine (PEI) with negatively charged CNTs-COOH constructed the superhydrophilic Cassie–Baxter structure onto the electrospun polyacrylonitrile (PAN) membrane surface by ultrasonic, electrostatic interaction and thermal treatment. Based on it, the PEN@CNTs membrane achieved efficient separation for surfactant-free, tween 80-stabilized, SDS-stabilized, and CTAB-stabilized emulsions (the fluxes reached 508–3158 L m −2 h −1 , the separation efficiency reached 99.42%) by the splendid water-penetration and oil-repellency, electrostatic interaction, and “aperture sieve”. Moreover, because of the porosity and strong charged surface of PEN@CNTs membrane, the anionic dyes can be quickly removed by one-step filtrate method (∼403 L m −2 h −1 ). Meanwhile, the PEN@CNTs membrane also achieved synchronous and efficient remediation for oil/dye mixture emulsions after many cycles. More importantly, facing the complex physical and chemical environments, the combination of the stabilized PEN membrane, inactive CNTs-COOH layer, and the bond of embedding method between CNTs-COOH and PEN nanofibers made the PEN@CNTs membrane demonstrated robust stability and durable separation capability.
研究领域:
环境科学
·
材料科学
·
水处理
·
纳米技术
✓ 已验证
DOI
PubMed
高影响因子
COLLOIDS AND SURFACES A-PHYSICOCHEMICAL AND ENGINEERING ASPECTS
·
2022
·
IF 5.518
Xu Li,Chunsheng Pu,Yun Bai,Feifei Huang
Multiwalled Carbon nanotube (MWCNT) serves as one of emerging and attractive materials for stabilizing foams due to its small size, special surface property and rod-like structure. The combination of MWCNT and surfactant has been regarded as an effective strategy to improve foam stability in porous media . However, the effects of surfactant types on the dispersity of MWCNT and on the stability of MWCNT stabilized foams have yet to be clearly understood. More importantly, the lack of comprehensive study of the synergistic interactions between surfactants and MWCNTs seriously limits the understanding of MWCNT’s foam-stabilizing mechanism, restricting its application as the foam stabilizer . Herein, this paper aims to systematically study the foam-stabilizing performance and mechanism of different surfactant/MWCNT foam systems. Combining with the experimental results obtained from ultraviolet and visible spectrophotometry and zeta potential tests, environmental scanning electron microscope analyses, contact angle measurements, optical microscope observations, and surface tension and dilational viscoelastic modulus determinations, the foam-stabilizing mechanism of different surfactant/MWCNT foam systems can be conjectured as follows. Compared with anionic and nonionic surfactants (SDS and OP-10) modified MWCNT, the MWCNT modified by the cationic surfactant (CTAB) can yield better dispersity due to the larger electrostatic repulsion and higher steric resistance between MWCNTs after the adsorption of CTAB . The highly dispersed MWCNTs have small sizes, which make them enter the foam film easily and tend to aggregate at Plateau border. These aggregations can significantly slow down the film drainage. In addition, MWCNTs can improve the viscosity of foam film, which helps to increase the resistance of gas diffusion and mitigate bubble coalescence . After being adsorbed by surfactants, the modified MWCNT can adsorb on the air-water interface. Due to the higher detachment energy, the CTAB modified MWCNT has a stronger adsorption capacity at the air-water interface compared with SDS and OP-10 modified ones. This tight adsorption can improve the dilational viscoelastic modulus and thus enhance foam stability. Finally, the dual-sand pack experiments proved that the CTAB/MWCNT stabilized foams have good potential for conformance control in heterogenous reservoirs.
研究领域:
材料科学
·
化学工程
·
胶体与表面化学
·
石油工程
✓ 已验证
DOI
高影响因子
SEPARATION AND PURIFICATION TECHNOLOGY
·
2021
·
IF 7.312
Nan Hu,Keke Zhang,Yanfei Li,Tianyu Hou,Zhijun Zhang,Huizhen Li
The utilization of agro-food waste into protein products is an alternative solution for global protein shortage and waste management. Perilla ( Perilla frutescens L.) seed meal (PSM) is abundant and protein-rich by-products from the oilseed industry. To achieve the industrial production of valuable PSM protein (PSMP), a two-stage foam separation with a low cost and a high efficiency was developed to fractionate the high-concentration PSMP (1.3 times its critical micelle concentration (CMC)) from its crude extract. In the first-stage, glycine betaine (GB), a naturally occurring osmolyte, was used as a green enhancer for the recovery of PSMP. The result of SEM, FTIR, UV–vis and fluorescence spectra demonstrated that GB engaged in cation-π interactions with aromatic residues of PSMP, which made the protein structure unfold and enabled its hydrophobic groups of PSMP to be more exposed. These factors, plus protein aggregation, were responsible for the enhanced interfacial adsorption of PSMP. Its recovery percentage with 0.3 g/L GB (pH 7.0) increased by 52.9% compared to that without GB. Furthermore, an internal component of regular-hexagon hollow prismoid (RHP) was also designed to intensify the foam drainage and raise PSMP enrichment to 7.1 ± 0.3. In the second-stage, PSMP could be further recovered and its total recovery percentage reached 94.5 ± 4.7%. After foam separation, the amino acid composition of PSMP was analyzed by SDS-PAGE and HPLC–UV and its functional properties was also evaluated. These results provide a new insight into enhancing the protein separation from agro-food waste.
研究领域:
食品科学
·
蛋白质工程
·
废物管理
·
生物技术
✓ 已验证
产品关联
DOI
高影响因子
BIOPHYSICAL CHEMISTRY
·
2020
·
IF 1.995
Man Lyu,Huijun Liu,Yalin Ye,Zongning Yin
This study was aimed to investigate the inhibition effect of thiol-type antioxidants on protein oxidative aggregation caused by free radicals and the underlying mechanisms using six different thiol-type antioxidants ( N -acetyl-L-cysteine, methionine , taurine, alpha-lipoic acid, glutathione and thioproline), Cu 2+ –H 2 O 2 as a free radical generator (mainly a hydroxyl radical generator) and bovine serum albumin as the model protein. The inhibition effect of these antioxidants on protein oxidative aggregation and protective effect against oxidative damage in mouse brain tissues were investigated using SDS-PAGE, intrinsic fluorescence, simultaneous fluorescence, thioflavin T fluorescence, Congo red absorbance and inverted microscope. The results showed that all six antioxidants could inhibit protein oxidative aggregation by scavenging free radicals. In addition, alpha-lipoic acid could also bind to proteins via hydrophobic interactions and thioproline could bind to proteins via hydrogen bonds and van der Waals forces , thereby showing much stronger inhibition effect than others. Moreover, alpha-lipoic acid and thioproline could effectively prevent oxidative damage of mouse brain tissues. These results suggest that alpha-lipoic acid and thioproline can effectively inhibit free radical-induced protein aggregation and brain damage, which are worth testing for further anti-Alzheimer properties.
研究领域:
生物化学
·
药理学
·
神经科学
·
分子生物学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Food Chemistry-X
·
2022
·
IF 6.443
Xin Luo,Jiankang Lu,Yongyan Wu,Wenshan Duan,Fengping An,Qun Huang,Lei Chen,Shaofeng Wei
Potential allergenicity of amandin was reduced by binding amandin with (−)-epigallocatechin gallate (EGCG) via alkaline, free radical, ultrasound-assisted alkaline, and ultrasound-assisted free radical methods. These results of total phenol content, free sulfhydryl group, free amino group, surface hydrophobicity, and sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE) indicated that amandin might be covalently bound to EGCG through reactive groups such as sulfhydryl and amino groups, or non-covalently through hydrophobic interactions. Fourier transformed infrared (FT-IR) spectroscopy and fluorescence spectroscopy revealed structural changes of amandin-EGCG conjugate, which also caused significant reduction in potential allergenicity of amandin. Liquid chromatography-tandem mass spectrometry (LC-MS/MS) found that amandin bound to EGCG mainly through cysteine and glutamate residues, and linear epitope for amandin was reduced. This provided a new method and theoretical basis of hypoallergenic almond food.
研究领域:
食品科学
·
过敏学
·
化学
·
生物化学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
危险品化学品经营许可证（带存储）