Journal of Environmental Chemical Engineering
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2023
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IF 7.7
Jiguang Huang,Haiping Chen,Run Qi,Jihao Yang,Zhaohao Li,Heng Zhang
Coal fly ash (CFA) is a substitute material for ceramic membrane which can effectively reduce the preparation cost. However, CFA based ceramic membranes usually show insufficient mechanical strength for application. Revealing pore-forming mechanisms of different pore-forming agents in membranes preparation is of great significance to improve mechanical strength without harming permeability. In this work, three different pore-forming agents, carbon powder, dolomite and dextrin, were adopted to prepare CFA membranes. Characters including porosity, pore size distribution and permeability of membranes were comparatively analyzed. Effects of pore-forming agents on membranes were discussed. The membrane with dextrin at 1200 °C sintering showed the best comprehensive properties. Its porosity, flexural strength and Darcian permeability coefficient were 39.46 %, 35.56 MPa and 3.84 × 10 −14 m 2 , respectively. Application in oil-in-water emulsion separation indicated higher than 94 % oil rejection. This research provides experimental bases for improving performances of low-cost CFA membranes, thereby conducive to engineering applications.
研究领域:
材料科学
·
环境工程
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产品关联
DOI
高影响因子
EUROPEAN JOURNAL OF PHARMACEUTICAL SCIENCES
·
2017
·
IF 3.756
Shuli Zhang,Xuan Meng,Zheng Wang,Aiping Fan,Guocheng Wang,Yanjun Zhao,Yu Tang
It is often challenging to precisely manipulate the release behavior of hydrophilic drugs that is believed to be crucial for a satisfactory therapeutic outcome. The aim of this work was to regulate the dissolution of hydrophilic drug from hot-melt extruded solid dispersion via rational screening of the pore-forming agents. Venlafaxine hydrochloride and Compritol® 888 ATO was selected as the model drug and carrier excipient, respectively. Hydrophilic polyethylene glycol (PEG 6000) and polyvinylpyrolidone (PVP K30) were chosen as the transient pore-forming agents. The X-ray diffraction and thermal analysis showed that both drug and carrier existed in the crystalline form. Both types of polymers could generate pores upon dissolution test and the drug release rate was proportionally correlated to the pore-forming agent content. The mathematical modelling showed that the Ritger-Peppas model gave the best fit to the release curves, which demonstrates a diffusion-dominant release mechanism. The scanning electron microscopy and mercury intrusion porosimetry analysis proved that PVP K30 could generate large pores with low porosity, but PEG 6000 produced smaller pores with relatively high porosity. The in vivo pharmacokinetics study in rat revealed that solid dispersions containing either PEG 6000 or PVP K30 (both at 2.5%, w/w) exhibited an elevated bioavailability compared to the commercial product, Effexor® XR. The current work implied that rational screening of transient pore-forming polymer in solid dispersion could be a robust approach for controlling hydrophilic drug release.
研究领域:
药剂学
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药物释放系统
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DOI
PubMed
高影响因子
Journal of Energy Storage
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2024
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IF 8.9
Xinglin Luo,Congwei Wang,Kun Zhang,Rongyu Li,Gang Li
The widely applicable gel polymer electrolytes (GPEs) hold significant promise for the commercialization of low-temperature flexible quasi-solid-state supercapacitors (FQSCs). However, their flexibility and electrochemical performance are compromised under extreme cold conditions, severely limiting their practical applications. Inspired by the novel effects of “pore-form agents (PFA)”in hydrogel-controlled drug release & delivery, polyvinyl alcohol (PVA) hydrogel electrolytes with optimized internal porosity (polymeric structure) were prepared by introducing PFA as pore-regulator and in-situ leaching process, hereby enhancing the hydrogel's electrical conductivity and low-temperature performance. Furthermore, in order to further enhance its low-temperature tolerance, the composition of the electrolyte was adjusted via binary solvent replacement method. FQSCs composed of PVA-PFA30-EG exhibited significantly improved high specific capacitances of 131.72 F g −1 at 25 °C and 72.90 F g −1 at −40 °C when tested at 1 A g −1 , with only a 6.36 % capacitance decay after 10,000 cycles at −40 °C. This performance surpasses that of most previously reported low-temperature FQSCs. The novel approach proposed in this paper provides a new avenue for flexible energy storage devices in extremely cold conditions.
研究领域:
材料科学
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能源存储
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化学工程
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产品关联
DOI
高影响因子
INDUSTRIAL & ENGINEERING CHEMISTRY RESEARCH
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2023
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IF 4.2
Chenyu Zhu,Xue Zhang,Fuzhi Li,Ruochen Yang,Xuan Zhao
Thin-film composite (TFC) nanofiltration (NF) has been widely utilized to separate monovalent ions from multivalent ions in industrial wastewater treatment. In this study, the pore properties of polyvinylidene fluoride (PVDF) substrates were adjusted by varying the content and molecular weights (MWs) of porogen polyethylene glycol (PEG). The TFC membranes fabricated on different substrates showed distinguishable permeance and selectivity. The PVDF membranes with 2 kDa PEG of 0.5–3.0 wt % and 20 kDa PEG of 0.2 wt % were fit for the substrates of the TFC NF membrane. These substrates are usually characterized by evenly distributed surface pores with porosity of 7–12% and tiny finger-like pores of less than 15 μm length. Such pore structures in the substrates are fit for the storage and migration of amine monomers, resulting in a defect-free PA layer. In a 6 h filtration of mining wastewater using an optimized TFC membrane, the permeance remained around 5 LMH/bar and the separation factor of SO42–/Cl– stayed over 13.39 with a maximum value over 30. This study shed light on improving NF membrane performance by simply adjusting the porogen in the substrate casting solution.
研究领域:
环境科学
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材料科学
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膜技术
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产品关联
DOI
高影响因子
CHEMISTRY-A EUROPEAN JOURNAL
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2018
·Vol. 24
·期 41
·10460-10467
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IF 5.16
Ruiying Shi,Cuiping Han,Xiaofu Xu,Xianying Qin,Lei Xu,Hongfei Li,Junqin Li,Ching-Ping Wong,Baohua Li
Graphical Highly graphitized : A highly graphitized activated carbon nanofiber (a-PANF) has been obtained by a bottom-up synthesis involving electrospinning of polyacrylonitrile followed by calcination and chemical activation (see figure). The product has a hierarchical porous structure and abundant N-heteroatom doping. The lithium-ion capacitor (LIC) has been regarded as a promising device that combines the merits of lithium-ion batteries and supercapacitors, and that meets the requirements for both high energy and high power density. The development of advanced electrode materials is the key requirement. Herein, we report the bottom-up synthesis of activated carbon nanofiber (a-PANF) with a hierarchical porous structure and a high degree of graphitization. Electrospinning has been employed to prepare an interconnected fiber network with macropores, and ferric acetylacetonate has been introduced as both a mesopore-creating agent and a graphitic catalyst to increase the degree of graphitization. Furthermore, chemical activation enlarges the specific surface area by producing abundant micropores. Half-cell evaluation of the as-prepared a-PANF gave a discharge capacity of 80 mA h g −1 at 0.1 A g −1 within 2–4.5 V and no capacity fading after 1000 cycles at 2 A g −1 , which represents a significant improvement compared to conventional activated carbon (AC). Furthermore, an as-assembled LIC with a-PANF cathode and Fe 3 O 4 anode showed a superior energy density of 124.6 W h kg −1 at a specific power of 93.8 W kg −1 , which remained at 103.7 W h kg −1 at 4687.5 W kg −1 . This indicates promising application potential of a-PANF as an electrode material for efficient energy storage systems.
研究领域:
材料科学
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电化学
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能源存储
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纳米技术
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DOI
高影响因子
CHROMATOGRAPHIA
·
2016
·Vol. 80
·期 1
·23-30
·
IF 1.332
Guo Ruixian,Zhang Doudou,Zhu Xianghui,Tang Liying,Zhang Xuemeng,Bai Ligai,Liu Haiyan
A polymer-based monolithic column was prepared for high-performance liquid chromatography (HPLC), using ionic liquids as porogen within the confines of a stainless steel column (50 × 4.6 mm i.d.). In the process, 1-butyl-3-methylimidazolium chloride and dodecyl alcohol were used as bi-porogens, vinyl ester resin as the monomer, ethyleneglycol dimethacrylate as the crosslinker, CCl 4 as the initiator, and FeCl 2 as the catalytic agent to prepare the polymer-based monolithic column. Scanning electron microscopy, nitrogen adsorption–desorption instrument, and mercury intrusion porosimetry were used to assay the characteristics of the monolith, respectively. The optimized monolith showed uniform structure and good permeability. Then, the column was used as the stationary phase of HPLC to separate standard proteins and human plasma with gradient elution. Besides, the monolith was used to separate aromatic compounds from the mixture. The results showed that the addition of IL could effectively improve the structure of monoliths prepared by atom transfer radical polymerization technique. The results also suggested that this kind of monolith could be used as a simple, cheap and effective stationary phase for HPLC.
研究领域:
分析化学
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材料科学
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色谱学
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产品关联
DOI
高影响因子
危险品化学品经营许可证（带存储）