CERAMICS INTERNATIONAL
·
2020
·
IF 3.83
Zhongliu Wen,Xiaolei Song,Dongchu Chen,Ting Fan,Yang Liu,Qingshan Cai
In this work, diphasic mullite (3Al 2 O 3 ·2SiO 2 ) nanofibers with good homogeneity were prepared by electrospinning method. Aluminum nitrate (AN) and aluminum isopropoxide (AIP) were used as alumina sources, commercial colloidal silica as silica source, and polyvinyl alcohol (PVA) as polymer additive . Precursor nanofibers with continuous and uniform structures were acquired at mass ratio of PVA to precursor sol from 0.06 to 0.09. γ- Al 2 O 3 phase was obtained at 878 ° C and mullite phase formed at 1322 ° C upon heating of the precursor under air atmosphere. Calcined samples suggested mullite as dominant phase at 1300 ° C and amorphous SiO 2 could even exist at 1400 ° C. As-prepared nanofibers possessed continuous structures with subequal average diameters at 900–1200 °C. However, such morphological characteristics were lost at temperatures above 1300 ° C due to rapid growth of crystal grains. Al and Si elements were uniformly distributed in fibers and mixed at nanoscale, confirming homogeneity and diphasic features of nanofibers.
研究领域:
材料科学
·
陶瓷学
✓ 已验证
产品关联
DOI
高影响因子
COLLOIDS AND SURFACES A-PHYSICOCHEMICAL AND ENGINEERING ASPECTS
·
2023
·
IF 5.2
Hao Wu,Tianyi Jiang,Wenlong Wu,Shanguo Zhang,Ming Li,Jingzhuo Zhou,Mengya Zhu,Juzheng Chen,Ziyong Li,Yang Lu,Hongyuan Jiang
Water-in-oil-in-water (W/O/W) double emulsion droplets are a typical colloidal system applied in various practical fields. However, certain high-specification applications necessitate exact geometric homogeneity in terms of both shell diameter and thickness. Despite achieving uniformity in shell diameter, on-chip microfluidic emulsification always leads to an eccentric phenomenon due to innate density differences of the droplet solution. At the same time, the current regulation methods have multiple limitations, including their applicability, regulatory scope, and objective restrictions. Herein, we propose an off-chip osmosis-induced hydrodynamic method to accurately regulate the eccentricity of W/O/W double emulsion droplets. The rational selection of hypertonic osmosis can energize the droplets and induce inward transmembrane water flux. This flow helps to reposition the droplet core to align concentrically with the shell, regardless of the initial dimension and eccentricity of the droplets. As the osmotic induction reduces due to the dilution of the inner solute molar concentration , the optimal droplet configuration can be achieved when osmosis-induced hydrodynamic regulation sufficiently counteracts the adverse effects of droplet solution density difference. The microcapsules can thus be produced by instant UV polymerization of the regulated double emulsion droplets, and the silica microspheres with fine geometric homogeneity can be prepared through further heat treatment, which is expected to meet the stringent morphological requirements in practical applications.
研究领域:
胶体与界面化学
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微流控技术
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生物材料
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药物递送系统
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高分子科学
✓ 已验证
DOI
高影响因子
Nature Water
·
2025
·
IF 24.1
Lu Dan,Huang Mi,Zhang Chi,Bu Guangle,Li Ge,Geng Yifang,Xu Shiying,Xiang Xinchen,Qian Yukun,Lu Jiancong,Yao Zhikan,Jiao Lei,Zhang Lin,Wang Rong
Ion-selective membranes, crucial for diverse applications such as water purification, brine disposal and resource recovery, rely heavily on the pore architecture and surface charge. Narrowing the pore size distribution (PSD) of the membrane is generally acknowledged to be essential for achieving higher ion selectivity. Here we challenge the conventional emphasis on PSD by introducing an alternative determinant—surface charge homogeneity—drawing inspiration from a counterintuitive relationship between PSD and ion selectivity observed in both commercial and laboratory-made polyamide nanofiltration membranes. By integrating multimodal atomic force microscopy technologies, we visually extracted nanoscale charge maps from three dimensions: surface potential, phase and functional groups. The metrological analysis methodology was originally developed to quantitatively describe the spatial charge distribution. It is demonstrated that nanoscale spatial charge homogeneity plays a crucial role in governing ion selectivity, surpassing the influence of PSD. Based on this perception, we devised the high-selective nanofiltration membranes and modules for the lithium–magnesium mixture separation by using a polyethyleneimine multivariate strategy to program polyamide membranes with stepwise-enhanced homogeneous distribution of electropositive-amine moieties. Our work unveils a unique charge homogeneity-dominated selectivity mechanism and demonstrates the feasibility of developing highly ion-selective membranes by facile nanocharge manipulation, surpassing the need for precise PSD control.
研究领域:
膜科学与技术
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分离科学
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材料化学
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环境工程
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资源回收
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水处理
✓ 已验证
DOI
高影响因子
Gels
·
2021
·Vol. 7
·期 4
·206
·
IF 4.702
Yu Guo,Jie Gu,Yuxin Jiang,Yanyan Zhou,Zhenshu Zhu,Tingting Ma,Yuanqi Cheng,Zongzhou Ji,Yonghua Jiao,Bin Xue,Yi Cao
Poly(ethylene glycol) (PEG)-based synthetic hydrogels based on Michael-type addition reaction have been widely used for cell culture and tissue engineering. However, recent studies showed that these types of hydrogels were not homogenous as expected since micro domains generated due to the fast reaction kinetics. Here, we demonstrated a new kind of method to prepare homogenous poly(ethylene glycol) hydrogels based on Michael-type addition using the side chain amine-contained short peptides. By introducing such a kind of short peptides, the homogeneity of crosslinking and mechanical property of the hydrogels has been also significantly enhanced. The compressive mechanical and recovery properties of the homogeneous hydrogels prepared in the presence of side chain amine-contained short peptides were more reliable than those of inhomogeneous hydrogels while the excellent biocompatibility remained unchanged. Furthermore, the reaction rate and gelation kinetics of maleimide- and thiol-terminated PEG were proved to be significantly slowed down in the presence of the side chain amine-contained short peptides, thus leading to the improved homogeneity of the hydrogels. We anticipate that this new method can be widely applied to hydrogel preparation and modification based on Michael-type addition gelation.Keywords:hydrogel;reaction kinetics;mechanical homogeneity;peptide
研究领域:
材料科学
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生物材料
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组织工程
·
细胞培养
✓ 已验证
DOI
PubMed
高影响因子
JOURNAL OF APPLIED POLYMER SCIENCE
·
2017
·Vol. 134
·期 41
·45405
·
IF 1.86
Weijie Li,Jian Hao,Pucha Zhou,Yaodong Liu,Chunxiang Lu,Zhengfang Zhang
In this study, we systematically explored the dependence of the homogeneity and sol–gel transition temperatures of various polyacrylonitrile (PAN) solutions on the solvent solubility parameters. The Cole–Cole slope was used to characterize the solution homogeneity, and we found that the PAN/dimethyl sulfoxide (DMSO) solution, which had a smaller Hansen solubility parameter distance between the solvent and PAN, showed better solution homogeneity than the PAN/dimethylformamide and PAN/dimethylacetamide solutions. Additionally, we found that both heating and cooling were able to cause the gelation of the PAN solution, although their mechanisms were totally different. The gelation caused by heating was ascribed to the nitrile–nitrile coupling of PAN chains, whereas the gelation caused by cooling was due to the solvent bridge effect. In this case, DMSO, which had the highest polarity and the strongest interactions with nitrile groups, caused the highest gelation temperature of the PAN solution during cooling. The gelation temperature of the PAN solution exhibits dependence on its solvent polarity. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2017 , 134 , 45405.
研究领域:
高分子科学
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材料科学
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化学工程
✓ 已验证
DOI
高影响因子
危险品化学品经营许可证（带存储）