SCIENCE OF THE TOTAL ENVIRONMENT
·
2018
·
IF 4.61
Shunquan Shi,Jiakuan Yang,Sha Liang,Mingyang Li,Quan Gan,Keke Xiao,Jingping Hu
Fe 3 O 4 @SiO 2 -NH 2 magnetic particles with core-shell structure were attached on carboxylated biochar derived from phoenix tree leaves to synthesize a novel magnetic biochar for removing Cr(VI) ions from acidic solutions. FSEM, FTEM, XRD characterizations of the synthesized magnetic biochar revealed that the Fe 3 O 4 @SiO 2 -NH 2 magnetic particles distributed uniformly on the surface or macrospores of carboxylated biochar by strong chemical bonding. The Cr(VI) ions adsorption capacity of magnetic biochar was 27.2 mg·g −1 , surpassing original carboxylated biochar (18.2 mg·g −1 ). VSM and XPS characterizations demonstrated that the attached Fe 3 O 4 @SiO 2 -NH 2 magnetic particles not only endowed biochar with perfect magnetic property (23 emu·g −1 ) but also provided complexing sites for binding Cr(III) cations reduced from Cr(VI) anions. The Cr(VI) ions removal by magnetic biochar contained three steps: (1) adsorption of Cr(VI) anions by protonated functional groups; (2) reduction of Cr(VI) anions to Cr(III) cations by electron-donor groups; and (3) chelation of Cr(III) cations by amine groups. The adsorption recycling test showed that magnetic biochar kept 85% of its initial Cr(VI) adsorption capacity at the sixth cycle, and the Fe leakage under pH 1.0 was smaller than 0.25 mg·L −1 . The results indicated that this novel magnetic biochar was applicable for the practical treatment of Cr(VI)-containing wastewater.
研究领域:
环境科学
·
材料科学
✓ 已验证
DOI
PubMed
高影响因子
JOURNAL OF SOL-GEL SCIENCE AND TECHNOLOGY
·
2012
·Vol. 64
·期 2
·347-357
·
IF 1.632
Zhang Jian-Ming,Zhai Shang-Ru,Zhai Bin,An Qing-Da,Tian Ge
Multifunctional nanomaterials with task-specific physicochemical properties, especially core–shell nanostructures with Fe 3 O 4 core and NH 2 -functional shells (Fe 3 O 4 @SiO 2 –NH 2 ), have been extensively investigated as high-performance adsorbents, catalysts and catalyst supports; and in most cases the controllable sol–gel technique is the choice for fabrication of this kind of widely applied materials. Herein, we demonstrated that mono-dispersed and spherical Fe 3 O 4 @SiO 2 –NH 2 nanomaterials with magnetic response core, NH 2 -functional shell structure can be facilely prepared by co-condensation of TEOS with APTMS using a versatile sol–gel process. It was shown that the proper usage of APTMS and appropriate pre-hydrolysis time of TEOS were crucial and key steps for formation of highly uniform and desirable amino loading Fe 3 O 4 @SiO 2 –NH 2 materials. The TEOS pre-hydrolysis and the critical time (around 90 min) before the addition of APTMS prove to be vital for uniform structure evolution, while the appropriate concentration of APTMS (~2.28 mmol L −1 in our system) leads to well-dispersed materials with relatively high loading of amino functionality. The as-prepared Fe 3 O 4 @SiO 2 –NH 2 magnetic nanoparticles prepared under optimum conditions possessing superparamagnetic behavior, uniform core–shell structure (~200 nm in diameter), relatively large BET surface area (~138 m 2 /g) and high incorporation of amino-functionality (~2.90 wt %).
研究领域:
材料科学
·
化学工程
·
纳米技术
✓ 已验证
产品关联
DOI
高影响因子
MATERIALS RESEARCH BULLETIN
·
2014
·
IF 1.968
Shi Li,Shang-Ru Zhai,Qing-Da An,Ming-Hui Li,Yu Song,Xiao-Wei Song
The preparation of Co(II) supported magnetic heterogeneous catalyst, i.e. Fe 3 O 4 @SiO 2 –NH 2 @CS–Co, and its efficient and selective catalytic properties toward the oxidation of ethylbenzene to acetophenone are presented. The materials were characterized by various physicochemical techniques such as scanning electron microscopy, transmission electron microscopy, Fourier transform infrared spectroscopy, vibrating sample magnetometer, elemental analysis, inductively coupled plasma-atomic emission spectrometer and X-ray photoelectron spectroscopy, etc. The reaction conditions were thoroughly investigated and highly improved catalytic performance (82.5% conversion of ethylbenzene and 80.1% selectivity to acetophenone) was gained under more mild reaction conditions of lower temperature (70 °C), shorter reaction period (60 min) and cheaper and greener oxygen source (H 2 O 2 ). More importantly, it could be reused successively at least 10 times when more than 80% of its catalytic activity maintained.
研究领域:
材料科学
·
催化化学
·
环境化学
✓ 已验证
DOI
高影响因子
COLLOIDS AND SURFACES A-PHYSICOCHEMICAL AND ENGINEERING ASPECTS
·
2023
·
IF 5.2
Nian Li,Zi-jian He,Jia-hui Zhao,Zhi-dong Zhao,Xing-rui Qi,Hao-dong Wang,Bo Liu,Hua-jie Lai,Tao Jin
Developing magnetic adsorbent that combines the merits of quick response, excellent enrichment capacity, uniform and stable dispersivity is of paramount importance in pollutants pretreatment. In this work, tunable strawberry-like Fe 3 O 4 @SiO 2 -NH 2 @Au@ 2-ME magnetic solid phase extraction materials were prepared via assembly method. The obtained nanocomposites were characterized using scanning electron microscopy, X-ray diffraction spectroscopy, infrared spectroscopy , X-ray photoelectron spectroscopy, and whereafter the preparation method was optimized. Integrating magnetic solid-phase extraction with high-performance liquid chromatography and fluorescence detection , a comprehensive enrichment and detection method toward bisphenol A (BPA) was well established. This method demonstrated high efficiency and rapidity, achieving rapid enrichment of BPA. The as-developed method exhibited good linear correlation within the range of 10.0–500 μg·L −1 , with a recovery of 85–92%. It showed excellent sensitivity and reproducibility in BPA extraction with low limit of detection (LOD, 0.274 μg·L −1 ), limit of quantitation (LOQ, 0.913 μg·L −1 ) and relative standard deviation (RSD, 1.5%, n = 6), respectively. The proposed Fe 3 O 4 @SiO 2 -NH 2 @Au nanoplatform firmly supports the envision that proper surface functionalization of magnetic substrate could promote the enrichment capacity toward various pollutants in actual application scenarios.
研究领域:
环境科学
·
分析化学
·
材料科学
✓ 已验证
产品关联
DOI
高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2012
·
IF 3.461
Jianming Zhang,Shangru Zhai,Shi Li,Zuoyi Xiao,Yu Song,Qingda An,Ge Tian
Contamination of natural water with heavy metals (especially lead ions) is a problem of major concern and thus great demand of effective adsorbents for removal of toxic ions is increasing. Due to the task-specific properties of amino groups, core–shell nanostructures of Fe 3 O 4 @SiO 2 –NH 2 have been extensively investigated as advanced adsorbents; however, most studies on surface modification of Fe 3 O 4 @SiO 2 substances were of environmentally inefficient grafting methods. Herein, we demonstrated that mono-dispersed and spherical Fe 3 O 4 @SiO 2 –NH 2 nanomaterials can be facilely prepared by co-condensation of TEOS with APTMS employing a green sol–gel process. The as-prepared Fe 3 O 4 @SiO 2 –NH 2 magnetic nanoparticles (MNPs) prepared under optimum conditions possessing uniform core–shell structure (∼200 nm in diameter), relatively high loading of amino-functionality (∼5.45 wt%), easy recovery by external magnet and effective removal of Pb(II) ( q m = 243.9 mg/g, 25 °C). The adsorption was shown to be effective and a higher temperature was more favorable for the adsorption. The adsorption equilibrium data obeyed the Langmuir model and the kinetic data were well fitted to the pseudo-second-order model. Thermodynamic studies revealed the feasibility and endothermic nature of the system. These results demonstrated that the sol–gel produced Fe 3 O 4 @SiO 2 –NH 2 , due to its easy synthesis and recovery and eco-friendliness, can be a potential adsorbent for Pb(II) removal.
研究领域:
环境科学
·
材料科学
✓ 已验证
产品关联
DOI
高影响因子
ENZYME AND MICROBIAL TECHNOLOGY
·
2019
·
IF 3.553
Xuejia Shi,Jin Xu,Changning Lu,Zhenzhong Wang,Wei Xiao,Linguo Zhao
The magnetic particle Fe 3 O 4 -SiO 2 -NH 2 -Cellu-ZIF8 (FSNCZ8) was used to immobilize the high-temperature resistant GH3 β-glucosidase (Tpebgl3) from the Thermomotoga petrophila DSM 13995. The Tpebgl3 has great potential in the catalytic conversion of pharmaceutically active components. The magnetic carrier (FSNCZ8) which provided stronger adsorption capacity, magnetic and high-temperature stability than the previously discussed Fe 3 O 4 -NH 2 -Cellu-ZIF8 without tetraethyl silicate coated. The properties of FSNCZ8-Tpebgl3 (FSNCZ8-T) were as follows: The optimal temperature and pH were 90 °C and 5.5, respectively; the highest activity of FSNCZ8-T approached 2672 U/g; Fe 2+ enabled immobilized enzyme to increase its relative activity to 194%. The main characteristics of FSNCZ8-T, including thermal stability, pH stability, and glucose tolerance, were greatly enhanced by adding Fe 2+ , which was also superior to free enzymes; moreover, the residual activity of FSNCZ8-T was 74% of the initial activity at the end of 10 repeated cycles.
研究领域:
生物化学
·
酶工程
·
材料科学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
BIOINORGANIC CHEMISTRY AND APPLICATIONS
·
2022
·
IF 4.724
Yuqin Yang,Junjie Miao,Zhendong Yin,Weili Hao,Hongmei Shi,Ling Ma,Tiesheng Shi
Efficient extractions of trace antibiotic residues in the environment are a key factor for accurate quantification of the residues. A new nanoporous material, namely, magnetically covalent organic polymer (MCOP, Fe3O4@SiO2-NH2-COP) was synthesized in this work and was used for magnetic solid-phase extraction (MSPE). The combination of MSPE with high-performance liquid chromatography separation together with ultraviolet detection (HPLC-UV) was established as an effective method for the determination of four sulfonamide (SA) residues in surface water surrounding a cattle farm. The synthesized magnetic material was characterized by SEM, TEM, FT-IR, magnetic properties measurement system (MPMS), and nitrogen gas porosimetry. The material possessed many attractive features, such as a unique microporous structure, a larger specific surface area (137.93 m2·g−1) than bare Fe3O4 (24.84 m2·g−1), high saturation magnetization (50.5 emu·g−1), open adsorption sites, and high stability. The influencing parameters, including pH, the used amount of MCOPs, the type of eluent, adsorption solution, and desorption time, were optimized. Under the optimized conditions, the method conferred good linearity ranges (R2 ≥ 0.9990), low detection limits (S/N = 3, LOD, 0.10–0.25 μg·L−1), and satisfactory recoveries (79.7% to 92.2%). The enrichment factor (EF) for the four SAs was 34.13–38.86. The relative standard deviations of intraday (n = 5) and of interday (n = 3) were less than 4.8% and 8.9%, respectively. The equilibria between extraction and desorption for SAs could be reached within 150 s. The proposed method was sensitive and convenient for detecting SA residues in complex environmental matrices, and the successful application of the new MCOPs as an adsorbent was demonstrated.
研究领域:
环境科学
·
分析化学
·
材料科学
·
水质
✓ 已验证
产品关联
DOI
PubMed
高影响因子
RSC Advances
·
2016
·Vol. 6
·期 97
·94976-94988
·
IF 3.289
Longfei Liao,Ying Liu,Zengyong Li,Junping Zhuang,Yanbin Zhou,Size Chen
Amino modified Fe3O4@SiO2 (Fe3O4@SiO2–NH2) was used to immobilize Cu2+ and VO2+ for preparing Fe3O4@SiO2–NH2–Cu2+ and Fe3O4@SiO2–NH2–VO2+ catalysts. Various technologies had been used for the characteristics of catalysts, such as XRD, XPS, FT-IR, SEM, TEM and VSM. The catalytic performance of Fe3O4@SiO2–NH2–VO2+ in HMF oxidation could be significantly enhanced by the use of Fe3O4@SiO2–NH2–Cu2+ as the co-catalysts. The type of reaction solvents showed a great influence on the oxidation of HMF. The highest HMF conversion reached up to 98.7% at 110 °C in toluene with an optimal 2,5-diformylfuran yield of 85.5%. Moreover, the Fe3O4@SiO2–NH2–Cu2+ and Fe3O4@SiO2–NH2–VO2+ catalyst exhibited great stability and could be readily applied in the next recycle after magnetic separation.
研究领域:
化学工程
·
催化材料
✓ 已验证
产品关联
DOI
高影响因子
INTERNATIONAL JOURNAL OF BIOLOGICAL MACROMOLECULES
·
2016
·
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
·
纳米生物学
·
酶工程
✓ 已验证
产品关联
DOI
PubMed
高影响因子
JOURNAL OF THERMAL ANALYSIS AND CALORIMETRY
·
2025
·
IF 3.1
Jin Jiafei,Cai Xiaoming,Zhang Zhiwu,Zhao Ziming,Fu Han,Tang Junwen,Xiao Weiqi,Qin Ming,Cai Jinming
As the power density of electronic devices continues to increase, traditional coolants (e.g., water and ethylene glycol) are unable to meet the demand for efficient heat dissipation. This study prepared graphene oxide (GO)/aminated iron (III) oxide (Fe 3 O 4 @SiO 2 –NH 2 ) nanofluids (NFs, abbreviated as GF NFs) with different mass fractions, and systematically investigated their stability, thermophysical properties, and heat transfer enhancement (HTE) mechanism under magnetic field modulation. Experimental results show the following: The viscosity of NFs increases with rising particle concentration and decreases with increasing temperature; Conductivity increases with increasing concentration and temperature. For heat transfer performance, the convective heat transfer coefficient (h) of the NFs increased significantly with flow rate. Adding 0.05 mass% GF to the base fluid, the maximum HTE of GF NFs reached 120%. reducing the device temperature by 2.2 °C. Under a 1460 G magnetic field, the 0.1mass% GF NF reduced the device temperature by 2.6 °C compared to the base fluid. Combined with numerical simulations, this study reveals that the Brownian motion of nanoparticles (NPs) and magnetically induced micro-convection synergistically disrupt the thermal boundary layer, thereby enhancing the heat transfer performance of NFs. This study provides novel functionalized NF materials and regulation strategies for the intelligent thermal management of high-power electronic devices.
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF LUMINESCENCE
·
2018
·
IF 2.732
Nengtao Wu,Yiping Tang,Min Zeng,Jinwei Gao,Xubing Lu,Yuhui Zheng
An efficient way to assemble Fe 3 O 4 @SiO 2 -NH 2 nanocomposite has been developed by coupling (3-aminopropyl)trimethoxysilane onto surface of core-shell structure through facile impregnation of Fe 3 O 4 @SiO 2 decorated with amino groups. The key step during the synthesis involves the incorporation of organic fluorophore and amines are treated with 1,8-naphthalic anhydride. The achieved hybrid inorganic-organic nanoparticle gives rise to blue emissions and shows enough stability. Furthermore, Cu 2+ can be recognized by the organic building block via coordination reaction and the “on-off” quenching effect is observed. The nanosensor provides a response concentration range (1–6 μM) to Cu 2+ with the detection limit of 0.65 μM. Owing to the magnetic properties , the hybrid nanoprobe can be easily retrieved from aqueous solution for repeated uses via magnetic separation (35 s). This approach will offer an alternative way for designing novel detection systems in biological related fields.
研究领域:
材料科学
·
分析化学
·
生物医学工程
✓ 已验证
产品关联
DOI
高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2021
·
IF 13.273
Zhihui Chen,Jun Yao,Tatjana Šolević Knudsen,Bo Ma,Bang Liu,Hao Li,Xiaozhe Zhu,Chenchen Zhao,Wancheng Pang,Ying Cao
The environmental impact of the mining industry requires efficient and eco-friendly technologies to mitigate the presence of mineral flotation reagents (MFRs) in mineral processing wastewater (MPW) prior to their discharge into the environment. In this work, for the first time, a robust, easily separable and reusable biocatalyst, Fe 3 O 4 @SiO 2 -NH 2 -Lac, was used for the degradation of a novel mineral flotation reagent 8-hydroxyquinoline (8-HQ). Under optimized conditions, Fe 3 O 4 @SiO 2 -NH 2 -Lac achieved 89.2% 8-HQ degradation efficiency within 6 h. The effect of the main constituents of MPW on 8-HQ degradation, including metal ions, organic solvents, surfactant, metal chelator and flotation frother was evaluated. The Fe 3 O 4 @SiO 2 -NH 2 -Lac also displayed favorable degradation efficiency of 8-HQ in real lead–zinc mine water. The biocatalyst could be easily recovered and had a satisfactory reusability, retaining 64.5% of 8-HQ degradation efficiency in the sixth reaction cycle. Identification of intermediate products revealed that Fe 3 O 4 @SiO 2 -NH 2 -Lac mediated reaction predominantly generated various structural 8-HQ oligomers/polymers. A potential degradation pathway for 8-HQ was speculated as follows: Fe 3 O 4 @SiO 2 -NH 2 -Lac initially catalyzed the oxidation of 8-HQ to yield the corresponding reactive radical intermediates, which subsequently undergone self-coupling reaction via C − C and C − O − C covalent coupling at their ortho and/or para positions, finally forming oligomers and polymers. The inhibition assays of marine bacterium ( Vibrio fischeri ) demonstrated that the toxicity of 8-HQ and its intermediate products was effectively reduced after Fe 3 O 4 @SiO 2 -NH 2 -Lac treatment. The results of this study might present an alternative immobilized laccase-based clean biotechnology for the clean-up and detoxification of 8-HQ contaminated MPW.
研究领域:
环境科学
·
生物技术
·
化学工程
·
材料科学
✓ 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）