CERAMICS INTERNATIONAL
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2025
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IF 5.6
Xinyu Mu,Deng Lingli,Yang Guo,Rui Zhou,Xiaoying Guo,Xian Jian,Xiangyu Zhao
Construction of homogeneous composite structures based on covalent bond mediation represents an effective approach to achieve excellent microwave absorption performance (MAP). In this study, Ti 3 C 2 T x @Fe 3 O 4 @SiO 2 nanocomposites with uniform architecture were successfully fabricated using 3-aminopropyltrimethoxysilane (APTMS) as a coupling agent. By functionalizing Fe 3 O 4 @SiO 2 nanoparticles with surface amino groups via APTMS, covalent bonding was established between Ti 3 C 2 T x nanosheets through amide linkages, enabling homogeneous anchoring of Fe 3 O 4 @SiO 2 within Ti 3 C 2 T x . This fabrication method based on covalent bond mediation enhances interfacial polarization of the composite while simultaneously optimizing its conductive networks and impedance matching characteristics. Together with intrinsic magnetic resonance and eddy current loss mechanisms of Fe 3 O 4 , these enhancements endow the Ti 3 C 2 T x @Fe 3 O 4 @SiO 2 composites with exceptional MAP. At a thickness of 1.26 mm, the material exhibits an effective absorption bandwidth of 4.11 GHz, spanning the frequency range of the Ku band. At a slightly higher thickness (1.5 mm), a minimum reflection loss of −48.98 dB is attained. Notably, the composites also demonstrate superior thermal conductivity, enabling efficient electromagnetic energy dissipation through the conversion into thermal energy. The proposed covalent bonding-based scheme provides a theoretical framework for microstructure design and performance optimization of novel MXene-based microwave absorbers.
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高影响因子
INTERNATIONAL JOURNAL OF BIOLOGICAL MACROMOLECULES
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2016
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IF 3.138
Gang Fang,Honggao Chen,Yunpeng Zhang,Anqing Chen
Fe 3 O 4 magnetic nanometer particles (MNPS) with a diameter of 30–40 nm and coated by ammoniated silicon dioxides were developed by sol–gel method. The X-ray diffraction (XRD) pattern indicates that the Fe 3 O 4 is wrapped in the amorphous SiO 2 , and the Fourier-transform infrared spectroscopy (FT-IR) analysis confirmed the NH 2 group had been successfully introduced onto the surface of Fe 3 O 4 @SiO 2 nanoparticles. The main factors related to the immobilization process of pectinase onto the magnetic support were optimized by multi-factor orthogonal experiments, and the recommended combination is that 3% glutaraldehyde (coupling agent), pH = 8.0, 50 °C, and cross-linking time 8 h. Scanning electron microscope (SEM) and FT-IR analyses confirmed that the pectinase had been immobilized onto the surface of the amino modified nanoparticles. The storage stability and reusability of the pectinase were enhanced by the immobilization that 64.4% of the total starting activity was retrieved after 7 recycling batches and only about 21.1% of the total activity was lost after 30-day storage. For the application of the immobilized pectinase, the optimal pH and temperature were 8.5 and 55 °C, respectively.
研究领域:
生物化学
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纳米生物学
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酶工程
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DOI
PubMed
高影响因子
PHYSICAL CHEMISTRY CHEMICAL PHYSICS
·
2023
·Vol. 25
·期 37
·25780-25788
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IF 3.3
Runna He,Shuangqing Sun,Jianpeng Cui,Mingshuo Chi,Zhikun Wang,Songqing Hu
In recent years, Pickering emulsifiers have been widely used in various production fields due to their excellent structural stability, biocompatibility and environmental friendliness. For some applications, it is required that the emulsifier can quickly respond to environmental stimuli and control the transition between stable and unstable emulsions. In this paper, we report a novel composite Pickering emulsifier with Fe3O4 as the core and magnetic response recognition body, silica as the intermediate protective layer, and chitosan (CS) of different molecular weights to endow solid particles with surface activity and pH-responsive properties. This emulsifier can stabilize the emulsion in the emulsion system with deionized water as the aqueous phase and liquid paraffin as the oil phase and can control the demulsification of the formed emulsion under the dual pH/magnetic stimulation. The experimental results show that Fe3O4@SiO2@CS has good paramagnetism and pH responsiveness. The particle size of the composite emulsifier nanoparticles is between 90 nm and 120 nm, and the best stabilizing effect of the emulsion is achieved when the dosage is 0.5 wt%. In the pH range of 3–11, the emulsifier can rapidly demulsify a stable paraffin oil–water emulsion system under the action of a magnetic field of strength 0.4 T. The pH response of the emulsifier is as follows: when pH ≤ 2, the system can form a stable emulsion, which is composed of fully protonated chitosan as a free chain segment and Fe3O4@SiO2. Emulsion stabilization was achieved with monolithic Fe3O4@SiO2@CS as an emulsifier at pH > 2, and demulsification was achieved at pH ≈ pKb (CS) at 298 K. The research in this paper can provide a feasible idea and synthesis method for the preparation of organic–inorganic composite structure emulsifier.
研究领域:
材料科学
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化学工程
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纳米技术
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DOI
PubMed
高影响因子
MATERIALS RESEARCH BULLETIN
·
2019
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IF 3.355
Li Guo,Qiang Zhao,Chan Wang,Huidong Shen,Xuanxu an Han,Kailai Zhang,Danjun Wang,Feng Fu
Novel core-shell structural magnetic Fe3O4@SiO2/Bi2WO6 (F-BWO) was obtained by a multistep process. Bi2S3 Quantum Dots (QDs) with the size of about 5 nm were deposited on the surface of Bi2WO6 “shell” to obtain Fe3O4@SiO2/Bi2WO6/Bi2S3 (F-BWO-BS) heterostructures. The experimental results indicated that F-BWO-BS exhibits the enhanced fuel oil photocatalytic-oxidative-desulfurization (Photo-Cat-ODS) and RhB photocatalytic degradation activity than that of F-BWO. The as-prepared F-BWO-BS-2 exhibited the best activity, the rate constant ( k app /min −1 ) for RhB photocatalytic degradation is approximately 1.5 times higher than that of F-BWO. Furthermore, the F-BWO-BS-2 exhibited the best Photo-Cat-ODS activity, the desulfurization rate could reach 100% after illumination for 1.5 h. The enhanced photocatalytic activity of F-BWO-BS can be attributed to the synergistic effect of magnetic Fe 3 O 4 @SiO 2 support − “core”, Bi 2 WO 6 − “shell” and Bi 2 S 3 QDs. The experimental result also revealed that magnetic F-BWO-BS photocatalyst is easily magnetically separated with good stability and recyclability.
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高影响因子
Micro & Nano Letters
·
2019
·Vol. 14
·期 13
·1287-1292
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IF 0.975
Feng Wang,Jie Li,Long Xu,Feng Jiang,Jianfeng Zhang
In this work, the study of synthesis and denitrogenation of magnetic polymeric ionic liquids (PILs) for N-compounds in simulated oils and diesel are reported. Three functionalised magnetic particles, Fe 3 O 4 @SiO 2 @PILs with side alkyl chain of C2, C4 and C6, respectively, were prepared by grafting PILs on the surface of silica-coated Fe 3 O 4 . Fourier transform infrared spectra, thermogravimetric analysis, X-ray diffraction and scanning electron microscopy were carried out to characterise the structure of Fe 3 O 4 @SiO 2 @PILs. It has shown that Fe 3 O 4 @SiO 2 @ PILs possess precious merits for sorbents, such as regular morphology, good stability and magnetic properties. Denitrogenation experiments of simulated oils demonstrate that Fe 3 O 4 @SiO 2 @ PILs show better denitrogenation efficiency of basic N-compounds than neutral N-compounds. The effects of temperature, reaction times, ratio of reagent to oil on denitrogenation for simulated oils were explored, and 92.1% denitrogenation efficiency was obtained to remove quinoline from simulated oils. Denitrogenation of Fe 3 O 4 @SiO 2 @PILs in diesel leads to 84.3% denitrogenation efficiency, and it can remain 82.5% denitrogenation efficiency after five times of recycles. Compared with other similar sorbents, Fe 3 O 4 @SiO 2 @PILs show competitive performances to eliminate organic N-compounds. It is hopeful that Fe 3 O 4 @SiO 2 @PILs can be promising sorbents for purification of liquid fuel by adsorptive denitrogenation.
研究领域:
化学工程
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材料科学
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DOI
高影响因子
ACS Applied Polymer Materials
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2019
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IF 0
Su-Na Yin,Juan Liu,Defeng Wu,Su Chen,Weiwei Xia
As important biological functions of many creatures, structural colors and self-healing features play crucial roles in the survival of organisms. Inspired by these features, the intelligent self-healing colloidal photonic crystals (CPCs) materials with stable structural colors are constructed here by immobilizing magnetically assembling Fe3O4@SiO2 colloidal nanoparticles into a self-repairing hydrogel matrix. The self-repairing hydrogels, prepared by using biodegradable material poly(1-vinyl-2-pyrrolidinone-co-acrylamide) modified with O-carboxymethyl chitosan (O-CMC), exhibit an outstanding mechanical property with favorable toughness and elasticity. Interestingly, one-dimensional Fe3O4@SiO2 chain structures embedded in the framework can maintain the stability of the photonic band-gap structure and its resultant bright structural colors. Furthermore, O-CMC contained in the matrix can supply plentiful carboxyl, amino, and hydroxyl functional groups which can form abundant intermolecular hydrogen bonds, and thus give the robust self-healing capability to the CPC colored hydrogels. On the basis of such CPCs hydrogels with bright structural colors and robust self-healing properties, a 3D flower pattern has been designed to realize arbitrary 3D configurable modeling. This work might constitute a promising simple way to fabricate structural colored CPC materials with a longer functional life, and thus extend their practical applications.
研究领域:
材料科学
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生物仿生学
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DOI
TALANTA
·
2017
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IF 4.162
Li Liang,Xinghua Wang,Ying Sun,Pinyi Ma,Xinpei Li,Huilan Piao,Yanxiao Jiang,Daqian Song
The metal-organic framework (MOF) functionalized magnetic graphene oxide/mesoporous silica composites (Fe 3 O 4 @SiO 2 -GO/MIL-101(Cr)) were synthesized and utilized as magnetic solid-phase extraction (MSPE) adsorbent for the extraction of seven triazine herbicides (terbuthylazine, secbumeton , terbumeton , atraton , atrazine , prometon and trietazine) in rice samples. Several experimental parameters, including type and volume of extraction solvent, amount of MIL-101(Cr), extraction time, volume of desorption solvent and desorption time were investigated and optimized. The limits of detection (LODs) of seven triazine herbicides obtained by using the proposed MSPE method combined with high performance liquid chromatography (HPLC) were in the range of 0.010–0.080 µg kg −1 . The recoveries of the triazine herbicides in spiked rice samples ranged from of 83.9–103.5% with the relative standard deviations lower than 8.7%. The intra and inter-day (n = 6) precisions for all triazine herbicides at the spiked level of 100.0 µg kg −1 were 1.4–5.9% and 2.6–7.8%, respectively.
研究领域:
分析化学
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环境科学
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DOI
PubMed
高影响因子
JOURNAL OF ORGANOMETALLIC CHEMISTRY
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2024
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IF 2.1
Haijiao Jia,Yuchen Cui,Xiaoqian Yuan,Yanmei Xu,Youxin Li
A kind of magnetic hybrid organic-inorganic nanoparticles containing Ru metal (Fe 3 O 4 @SiO 2 -FPBA-Ru) was prepared. It was spherical with the characteristic lattice fringe of ruthenium atom. The size was in the range of 5–15 nm and it contained 0.30 mmol/g Ru. Its saturation magnetization value was 15.95 emu/g, which could be easily and efficiently recovered from solution through an external magnet. It was also stable below 240°C and hot filtration experiment proved Ru wasn't leaked from Fe 3 O 4 @SiO 2 -FPBA-Ru in 70°C oxidation reaction. It could be recovered and reused at least 7 cycles. The low amount of Fe 3 O 4 @SiO 2 -FPBA-Ru (75 mmol%) could convert the 99 % of 1-phenylethanol to acetophenone under solvent-free system, which verified its green and environment-friendly properties. The yield was exceed that of homogeneous (RuCl 3 , 85 %). Beside this, the TON (5181), TOF (7430 h −1 ) in oxidation of 1-phenylethanol and high conversion yields for a series of oxidation reactions of aromatic secondary alcohols proved the high catalytic ability of Fe 3 O 4 @SiO 2 -FPBA-Ru. These laid a foundation for its industrial applications.
研究领域:
材料科学
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催化化学
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环境科学
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高影响因子
Journal of Cleaner Production
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2020
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IF 7.246
Bowei Shen,XueJun Yu,Farong Zhang,Wenxiu Jiang,Hui Yuan,Zhiquan Pan,Hong Zhou
A new method of the catalytic alcoholysis of Dioscorea zingiberensis C. H. Wright into diosgenin by magnetic solid acid in a Teflon-lined stainless-steel autoclave for the first time. The magnetic solid acid, Fe 3 O 4 @SiO 2 –SO 3 H, was prepared by the connecting the –SO 3 H groups on the surface of SiO 2 encapsulated Fe 3 O 4 microspheres . The synthesized catalysts were systematically analyzed by Fourier transform infrared (FT-IR) spectroscopy, thermogravimetric analyzer (TGA), X-ray diffraction (XRD), vibrating sample magnetometry (VSM), temperature programmed desorption of ammonia (NH 3 -TPD), scanning electron microscope (SEM), transmission electron microscope (TEM) and transmission electron microscope-mapping(TEM-mapping). To obtain the best conditions for the alcoholysis of Dioscorea zingiberensis C. H. Wright, single factor test was first utilized to determine the range of optimal conditions and optimized by response surface method . A three-level-three-factor Box-Behnken design was adopted to illustrate the effect of solid acid mass, solvent volume, reaction time and temperature on the yield of diosgenin. The optimum conditions obtained by response surface methodology were: 0.42 g Fe 3 O 4 @SiO 2 –SO 3 H, 4.38 mL solvent of ethanol, the reaction temperature at 100 °C and 6.09 h reaction time. At the optimal conditions, this method can reach the highest yield 2.64% from Dioscorea zingiberensis C. H. Wright. The yield of the new method was 21.66% higher than conventional sulfuric acid hydrolysis based on the analysis results of UV and HPLC. Importantly, the catalysts and solvents used in the alcoholysis process by the solid acid can be recovered, which is green and environmentally friendly, indicating that the catalytic alcoholysis with magnetic solid acid under hydrothermal conditions had a broad application prospect in diosgenin production.
研究领域:
植物化学
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药物化学
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绿色化学
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高影响因子
JOURNAL OF CHROMATOGRAPHY A
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2019
·
IF 3.858
Fenqi Ji,Rongrong Jin,Chen Luo,Chunhui Deng,Yaoming Hu,Li Wang,Rongchang Wang,Jiabin Zhang,Guoxin Song
In this paper, a novel core–shell structure magnetic microsphere Fe 3 O 4 @SiO 2 -TPM@StVp(Fe 3 O 4 @SiO 2 -3-(trimethoxysilyl)propyl methacrylate@styrene and n -vinylpyrrolidone) was successfully synthesized and used as a magnetic solid-phase extraction adsorbent for extraction of aristolochic acid I (AAI) in traditional Chinese medicine soup. The prepared Fe 3 O 4 @SiO 2 -TPM@StVp was characterized by transmission electron microscopy (TEM), scanning electron microscopy (SEM), vibrating sample magnetometer (VSM) and Fourier-transform infrared spectroscopy (FT-IR). The microspheres have various advantages of excellent hydrophilicity and π-electron system, which is very suitable for determining target analytes followed by high performance liquid chromatography (HPLC). The main factors, including the pH of samples, amount of adsorbent, adsorption time, elution solvent and desorption time, were optimized. Under optimal conditions, the proposed method showed a wide linear range of 0.4–10 µg/mL and a good correlation coefficient ( R 2 = 0.9918). The pretreatment procedure was achieved within 10 min. The recoveries of aristolochic acid I in real samples range from 80.9% to 89.6% with relative standard deviations less than 4.9%, highlighting the accuracy of this method.
研究领域:
分析化学
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中药学
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毒理学
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DOI
PubMed
高影响因子
APPLIED CATALYSIS A-GENERAL
·
2021
·
IF 5.706
Jing Ding,Chengwei Zhou,Zuowang Wu,Chong Chen,Nengjie Feng,Lei Wang,Hui Wan,Guofeng Guan
Construction of an efficient and separable Bronsted acid catalyst to realize one-pot conversion from low-value oils to biodiesel has been a hot and difficult spot in recent years. Herein, a novel magnetically recyclable catalyst was fabricated by grafting the sponge-like structure of poly (ionic liquid) on the surface of support Fe 3 O 4 /SiO 2 . The grafting copolymerization of dual-acidic ionic liquid (sulfonated vinylimidazolium ionic liquid) on the Fe 3 O 4 /SiO 2 was beneficial to enhance the strong acidity of the magnetic carrier and also made dual-acidic ionic liquid own excellent separation characteristics. The characterization results of the prepared composite showed that a sponge-like structure of poly(ionic liquid) was wrapped on the outer surface of Fe 3 O 4 @SiO 2 , thereby providing more active sites to reactants. Meanwhile, the catalyst possessed high magnetization value (14.3 emu/g) that resulted in the simple and rapid separation from the reaction system through an external magnetic field. Benefiting from the synergy effect between dual-acidic poly(ionic liquids) and magnetic carrier, Fe 3 O 4 @SiO 2 @PIL exhibited good catalytic performance with the oleic acid conversion of 92.1 % and the methyl oleate yield of 92.1 %. Besides, the recycled catalyst showed no significant loss in the catalytic activity after repeated use for six times.
研究领域:
材料科学
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催化化学
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能源化学
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DOI
高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2014
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IF 4.058
Xianfei Zeng,Yang Zhou,Wenhui Ma,Shixing Wang,Keqiang Xie,Jijun Wu,Kuixian Wei
Di(2-picolyl)amine derivates functionalized inorganic/organic hybrid magnetic network was prepared for selective detection and removal of Zn (II). A significant visual color change from colorless to pink-red was observed under the irradiation of 365 nm UV lamp. The inorganic/organic hybrid Fe 3 O 4 @SiO 2 nanoparticles were characterized by TEM, XRD, VSM, FT-IR, and TGA techniques. The fluorescence photograph showed that di(2-picolyl)amine functionalized Fe 3 O 4 @SiO 2 nanoparticles were sensitive and selective to Zn 2+ in acetonitrile solution. The di(2-picolyl)amine functionalized Fe 3 O 4 @SiO 2 nanoparticles with high saturation magnetization can conveniently separate metal ions from aqueous solution. Fluorescence spectra showed that the intensity varied obviously with the concentration of Zn 2+ . The removal efficiency of Zn 2+ can reach as high as 97.1% and the saturated adsorption amount of Zn 2+ is 161.6 mg/g. Langmuir linear fitting can illustrate the well consistent with the adsorption results.
研究领域:
化学
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材料科学
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环境科学
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DOI
高影响因子
危险品化学品经营许可证（带存储）