NEW JOURNAL OF CHEMISTRY
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2020
·Vol. 44
·期 27
·11704-11709
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IF 3.288
Chao Fan,Hao Tang,Licheng Wang,Yijing Li,Xusheng Wang,Shuai Wang,Xiaojing Liang
Using N-isopropylacrylamide (NIPAM) as a monomer, a core–shell material was successfully prepared via in situ polymerization on the surface of silica microspheres (named NIPAM@Sil), which acts as a hydrophilic interaction chromatography (HILIC) stationary phase. A method for the in situ polymerization of polymer monomers on a silica surface has been developed. It was shown using scanning electron microscopy (SEM) that NIPAM is evenly distributed on the surface of the silica. The synthesized NIPAM@Sil possesses a polar acylamino group arising from the polymerization of NIPAM. As demonstrated by the hydrophilicity, NIPAM@Sil showed excellent HILIC performance for the separation of hydrophilic compounds. This method provides a simple approach for the preparation of a polymer coated silica core–shell stationary phase.
研究领域:
分析化学
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材料科学
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产品关联
DOI
高影响因子
JOURNAL OF INDUSTRIAL AND ENGINEERING CHEMISTRY
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2024
·
IF 5.9
Yanping Ren,Xiaoqiang Fan,Kaiyue Lin,Shipeng Chen,Minhao Zhu
The preparation of a low shearing shell on the surface of carbon spheres (CS) is an attractive strategy to improve the lubrication properties of CS. In this study, core–shell structural C@Ag particles were prepared using CS as the hard core and Ag nanoparticles as the soft shell. Then, the additives were mixed with Polyalphaolefin 20 to prepare the C@Ag core–shell-enhanced lithium complex grease (C@Ag-LCG). The physicochemical properties, corrosion resistance, and tribological behaviors of LCGs were investigated. C@Ag-LCG exhibited the best high-temperature resistance and colloidal stability compared with the CS-enhanced lithium complex grease (LCG) and pure LCG. The dropping point and oil separation rate of 0.05 wt% C@Ag-LCG were 255 °C and 2.36 %, respectively. The tribological behavior of greases was tested using a four-ball friction tester, and the main damage mechanism was abrasive wear. The C@Ag additive reduced the average friction coefficient and wear spot diameter by 27.17 % and 26.12 %, respectively. The improved properties were attributed to the synergistic lubrication of hard CS core and soft Ag shell with the rolling, filling, and self-repairing effects, C@Ag deposit films and the self-lubricating oil film, as well as the thickener film and the tribochemical film at the frictional interfaces.
研究领域:
材料科学
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润滑工程
✓ 已验证
产品关联
DOI
高影响因子
COLLOIDS AND SURFACES A-PHYSICOCHEMICAL AND ENGINEERING ASPECTS
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2024
·
IF 4.9
Yang Xiao,Lin Zhang,Bin Wei,ChangFeng Lu,Ling Li
Generally, modification of materials by adding multiple types of nano particles could cause dispersion problems, generally limited the performance improvement effect. Herein, we report the modification of UHMWPE materials by organic-inorganic core-shell particles with PTFE as the core and Al(OH) 3 as the shell, which prepared by in-situ polymerization of sodium bicarbonate and aluminum sulfate solution . Core-shell particles were filled in UHMWPE matrix and sintered into composite by spark plasma sintering (SPS). The mechanical and tribological properties of the composites were characterized by tensile compression testing machine, universal micro tribometer (UMT-5), three-dimensional white light interferometer and scanning electron microscope (SEM). The results showed that the addition of core-shell structural materials effectively improved the tribological properties (friction coefficient decreased by 40%, wear rate decreased by 30%) and mechanical properties (compression strength increased by 2.4 times) of the composites. It was demonstrated that the inorganic framework provided strength to improve the mechanical properties and wear resistance of materials, and the organic phase was used as a lubricating phase to reduce the friction coefficient of materials. Surface treatment of core-shell particles both improved the binding between particles and matrix and decreased the formation of agglomerations, thus significantly reducing ploughing phenomena’s effect produced by abrasive wear of agglomeration
研究领域:
材料科学
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机械工程
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产品关联
DOI
高影响因子
Inorganic Chemistry Frontiers
·
2024
·
IF 6.1
Tianhao Yu,peng gao,Hong Du,ling dong
The oxygen evolution reaction (OER) requires the development of a strong and efficient electrocatalyst due to its slow mechanism and high overpotential. Hence, we assembled POM and NiCo-ZIF-67 to obtain the amorphous hollow core-shell material NiCo-ZIF-67@POM (donated as NiCo-ZIF@POM) with high catalytic activity. NiCo-ZIF@POM (1:3) presents a low overpotential (η≈150 mV@10 mA cm-2), a small Tafel slope (100 mV dec-1), and great stability for OER in 1 M KOH solution. Theoretical calculations indicate that the excellent activity of NiCo-ZIF@POM might be attributed to the charge rearrangement due to the interaction between Co and W. In addition, the low electronegativity of P and the high oxidation state of W in POM could accelerate the rapid OH- transfer and induce the intermediates to adsorb on the Co-O-W bridge bond conformation, which improves the performance of the catalytic OER. This study provides a new idea for the secondary assembly of POM and MOF materials.
研究领域:
材料科学
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电化学
✓ 已验证
产品关联
DOI
高影响因子
ANALYTICAL AND BIOANALYTICAL CHEMISTRY
·
2021
·Vol. 413
·期 28
·6987-6999
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IF 4.157
Yin Shi-Jun,Wang Xu,Jiang Hui,Lu Min,Zhou Xi,Li Li-Xian,Yang Feng-Qing
In this study, a magnetic yolk-shell structured metal-organic framework material (Fe 3 O 4 @YS-UiO-66-NH 2 ) is prepared by the directional etching of Co 2+ /peroxymonosulfate and in situ magnetization. The characteristic properties of the material were investigated by using field emission scanning electron microscopy, transmission electron microscopy, energy-dispersive X-ray spectroscopy, X-ray powder diffraction, Fourier transform infrared spectroscopy, vibrating sample magnetometer, Brunauer-Emmett-Teller, and contact angle test. The Fe 3 O 4 @YS-UiO-66-NH 2 shows the advantages of large surface area, good magnetic property, and satisfactory stability, as well as giving high affinity to alkaloids (ALs) via hydrophilic interaction, hydrogen bonding, and π-π interaction. The results of static adsorption experiment indicate that the Fe 3 O 4 @YS-UiO-66-NH 2 possesses high adsorption capacity towards ALs and the adsorption behaviors are fitted with Langmuir adsorption isotherm model. Furthermore, a magnetic solid-phase extraction using Fe 3 O 4 @YS-UiO-66-NH 2 and HPLC method was developed for the analysis of ALs in spiked samples with the recovery of 89.6–100.8%. In addition, the proposed method was successfully applied in the pharmacokinetics study of berberine, coptisine, and palmatine in the rat. In short, the developed method might be used for high-efficient recognition and determination of ALs in plasma sample, which would also provide a new way to fabricate magnetic functionalized metal-organic framework in separation science. Graphical abstract
研究领域:
材料科学
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分析化学
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药理学
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产品关联
DOI
PubMed
高影响因子
AICHE JOURNAL
·
2022
·Vol. 68
·期 8
·e17707
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IF 4.167
Xiaoquan Feng,Donglai Peng,Meixia Shan,Xinpu Niu,Yatao Zhang
The ZIF-8@Agmim core-shell hybrid material was synthesized via a favorable post-modification method of ion exchange (PMIE). This infrequent ZIF-8@Agmim core-shell structure maintains a well-integrated pore size that is almost the same as ZIF-8. The similar equilibrium isotherms with ZIF-8 and better kinetic separation toward propylene/propane than ZIF-8 render ZIF-8@Agmim to be an interesting candidate for propylene/propane separation. The core-shell hybrid nanomaterial was further used as nanofillers in the polymer of intrinsic microporosity matrix (PIM-1) for propylene/propane separation. The resultant mixed-matrix membranes (MMMs) exhibited a simultaneous increase in C 3 H 6 permeability and C 3 H 6 /C 3 H 8 ideal selectivity compared to pure polymer membrane owing to a synergistic effect of molecular sieving from ZIF-8 and π -complexation of Ag + with propylene. The separation performance of the prepared MMM surpasses the upper bound line of polymer membranes. Furthermore, the hybrid materials possess superb photochemical stability and the corresponding MMMs exhibit excellent anti-aging property and long-term stability.
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
Analytical Methods
·
2015
·Vol. 7
·期 8
·3486-3492
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IF 1.821
Houmei Liu,Yong Guo,Xusheng Wang,Xiaojing Liang,Xia Liu
In this paper, a novel sorbent, nano-Al2O3 coated mesoporous silica (Al2O3/SiO2), was prepared and used as a sorbent for solid-phase extraction of flavonoids. The synthesized sorbent material was characterized by X-ray photoelectron spectroscopy, energy dispersive spectroscopy and inductively coupled plasma emission spectrometry. The extraction properties of the resultant sorbent were evaluated by using four flavonoids (myricetin, quercetin, luteolin and kaempferol) as the test analytes. The extraction efficiencies of Al2O3/SiO2 were apparently superior to those of commercial C18 sorbents. Under optimal conditions, good linearities with R2 ranging from 98.8% to 99.8% were obtained and the LODs and LOQs were found to be in the range of 0.5–1 μg L−1 and 2.5–3 μg L−1, respectively. The proposed method was successfully applied for the real sample analysis of wild honey and red grape juice.
研究领域:
分析化学
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材料科学
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食品科学
✓ 已验证
产品关联
DOI
高影响因子
CHEMICAL ENGINEERING SCIENCE
·
2021
·
IF 4.311
Cunyin Zhang,Leibin Guo,Chengwei Deng,Haili Huang,Yuanhui Cheng
Aqueous zinc-based flow battery has advantages of low cost, high safety and abundant reservoir, showing a good application prospect. However, zinc dendrites remain a big issue to their cycling stability. Herein, we construct a multi-structured semi-solid anode by packaging multi-layered graphite felt and zinc slurry based on microporous carbon wrapped nano-ZnO ( [email protected] ). [email protected] is prepared by polymerizing dopamine on nano-ZnO and followed calcination . Microporous carbon shells act as restriction spaces, forbidding either oxidized or reduced zinc species flow out, but also serve as the first electron network. Meanwhile, carbon black and graphite felt function as the second and third electron networks. Besides, trace alkaline solutions deliver hydroxyl ions. Thus, the redox of zinc species proceeds in microporous carbon shells without zinc dendrites. Resultantly, semi-solid anode has high electrochemical activity and stability in zinc-iron flow batteries. The average efficiency is 74.8％ with negligible fluctuations over 840 h (460 cycles).
研究领域:
储能技术
·
材料科学
·
电化学
✓ 已验证
产品关联
DOI
高影响因子
危险品化学品经营许可证（带存储）