APPLIED SURFACE SCIENCE
·
2018
·
IF 4.439
Junjie Pan,Xin Sun,Tao Wang,Zetao Zhu,Yuping He,Wei Xia,Jianping He
Magnetic metallic materials compounded with dielectric loss materials are promising for efficient microwave absorption as a result of the synergistic effect between dielectric loss and magnetic loss, as well as the optimized impedance matching. In this paper, porous coin-like structured Fe@MoS 2 composite has been fabricated via solvothermal method accompanied by subsequent heat treatment under H 2 /Ar atmosphere. The structure and morphology of as-prepared Fe@MoS 2 composite indicates that MoS 2 nanosheets with the two-dimensional (2D) structure are well dispersed on the porous coin-like Fe micro-sheets to form a core-shell structure. Particularly, the addition of MoS 2 regulates the permittivity as well as improves the impedance matching of the Fe@MoS 2 composite. The as-prepared composite shows efficient microwave absorption properties with the maximum effective absorption bandwidth (reflection loss below −10 dB) of about 4.73 GHz (11.13–15.86 GHz) at the corresponding coating thickness of 2.0 mm, accompanied by the minimum reflection loss of about −37.02 dB. When the calcination temperature increases to 650 °C, the effective microwave absorption frequency band shifts to the lower frequency (9.91–14.19 GHz) with the minimum reflection loss of about −35.5 dB under the coating thickness of 2.0 mm. Considering the efficient microwave attenuation, the as-fabricated porous coin-like Fe@MoS 2 composite can be a hopeful candidate in the field of microwave absorption.
✓ 已验证
产品关联
DOI
高影响因子
PROPELLANTS EXPLOSIVES PYROTECHNICS
·
2018
·Vol. 43
·期 7
·637-641
·
IF 1.749
Naimeng Song,Jianchao Liu,Guoying Zhang,Zhenzhan Yan,Hongxu Gao,Li Yang
This paper describes the preparation of two combustion catalysts Tannin-Fe (Ta−Fe) and Phloroglucinol-Fe (Ph−Fe) by spray drying. The particle size and morphology of the particles are observed by scanning electron microscopy (SEM). The results of SEM image show that the particles are regular spherical and very good dispersion. The diameter of most spherical particles is about 1 μm. The effects of Ta−Fe and Ph−Fe on the thermal decomposition of RDX and AP were tested by differential scanning calorimeter (DSC). DSC dates show that Ta−Fe and Ph−Fe can advance the high temperature exothermic peak of AP 18.0 °C and 16.1 °C, respectively. The burning rates illustrates that both Ta−Fe and Ph−Fe can significantly increase the combustion rate of HTPB propellants. The formulation with 2 mass% Ta−Fe shows an average 21.31 % increase in burning rate and has a low value of the exponent n=0.48. The formulation with 2 mass%Ph−Fe has a burning rate 20 to 60 % larger than that of the initial AP/HTPB/Al formulation, and has a lowest exponent n=0.45.
✓ 已验证
产品关联
DOI
高影响因子
CATALYSIS TODAY
·
2018
·
IF 4.667
Luyao Ren,Liangzhong Li,Shuai Chen,Hui Li,Yongdi Liu,Liyang Zhou,Su Guo,YunJiang Yu
In this study, Fe/FeS@SiO 2 yolk-shell particles (Fe/FeS@SiO 2 YSPs) were synthesized, characterized, and applied to tetrabromobisphenol A (TBBPA) removal in simulated groundwater. The X-ray photoelectron spectroscopy, X-ray diffraction, Scanning electron microscopy, transmission electron microscopy and Brunauer Emmett Teller results revealed that Fe/FeS@SiO 2 YSPs possess special structures, including active cores, mesoporous networks, shells, hollow cavities and a large surface area (85 m 2 /g vs. 8 m 2 /g) compared to Fe/FeS. The mobility of the synthesized particles in porous media was simulated with sand column experiments. Fe/FeS@SiO 2 YSPs showed a much better transportability (83.02% of particles successfully transported through the column) than Fe/FeS particles (only 1.68%), related to the better suspension stability and much lower particle surface charge (−22.7 mV vs. −7.6 mV) at neutral pH. Improved TBBPA reduction performance in synthetic solution was observed for Fe/FeS@SiO 2 YSPs over bare Fe/FeS. The transformation pathway of TBBPA was studied in detail, revealing the formation of tri-BBPA, di-BBPA, mono-BBPA and BPA as the main products. In brief, thanks to the hollow mesoporous silica spheres (HMSS) coated on the surface of Fe/FeS particles, Fe/FeS@SiO 2 YSPs showed an enhanced dispersibility, transportability and degradation of TBBPA in simulated groundwater. The results in this study proved that Fe/FeS@SiO 2 YSPs are a promising material for in situ remediation of TBBPA in soil and groundwater.
✓ 已验证
产品关联
DOI
高影响因子
Micro & Nano Letters
·
2019
·Vol. 14
·期 9
·976-979
·
IF 0.975
Wen Zeng,Qiqi Yang,Bin Shao,Donglin Guo,Chunhong Li,Yilong Ma,Xueguo Yin,Sibo Zhao,Kejian Li
The monodisperse Fe@SiO 2 core-shell nanocapsules were synthesised via hydrothermal reaction followed with heat treatment. Nanostructures were characterised by X-ray diffraction, scanning electron microscopy and transmission electron microscopy. The magnetic properties of Fe@SiO 2 nanocapsules were evaluated with magnetic property measurement system. The results show that Fe@SiO 2 core-shell nanocapsules are highly monodispersed. The silica thickness of Fe@SiO 2 nanocapsules increased from 10–20 to 25–35 nm with increasing tetraethyl orthosilicate (TEOS) amount. In the Fe@SiO 2 nanocapsules prepared with 900 μl TEOS, as the reaction temperature increases, the mean particle size of Fe@SiO 2 nanocapsules increases from 328 to 546 nm. It is remarkable that the saturation magnetisation of Fe@SiO 2 nanocapsules decreases with increasing silica thickness. However, the coercivity of nanocapsules has less influence with the variation of silica thickness and particles’ length.
✓ 已验证
产品关联
DOI
高影响因子
Polymers
·
2018
·Vol. 10
·期 9
·934
·
IF 2.935
Guangqian Zhu,Xianhui Zhang,Mengmeng Zhao,Liang Wang,Chuyang Jing,Peng Wang,Xiaowu Wang,Qinggang Wang
A series of iminopyridine complexes of Fe(II) and Co(II) complexes bearing fluorinated aryl substituents were synthesized for the polymerization of isoprene. The structures of complexes3a,2band3bwere determined by X-ray diffraction analysis. Complex3acontained two iminopyridine ligands coordinated to the iron metal center forming an octahedral geometry, whereas2badopted a chloro-bridged dimer, and3bfeatured with two patterns of cobalt centers bridged via chlorine atoms. Complexes2band3brepresented rare examples of chlorine bridged bimetallic Co(II) complexes. The fluorine substituents effects, particularly on catalytic activity and polymer properties such as molecular weight and regio-/stereo-selectivity were investigated when these complexes were employed for isoprene polymerization. Among the Fe(II)/methylaluminoxane (MAO) systems, the 4-CF3substituted iminopyridine Fe(II) complex1awas found as a highly active isoprene polymerization catalyst exhibiting the highest activity of 106g·(mol of Fe)−1·h−1. The resultant polymer displayed lower molecular weight (Mn= 3.5 × 104g/mol) and moderate polydispersity index (PDI = 2.1). Furthermore, the ratio ofcis-1,4-/3,4 was not affected by the F substituents. In the series of Co(II)/AlEt2Cl binary systems, complexes containing electron-withdrawing N-aryl substituents (R = 4-CF3, 2,6-2F) afforded higher molecular weights polyisoprene than that was obtained by the complex containing electron-donating N-alkyl substituents (R = octyl). However, ternary components system, complex/MAO/[Ph3C][B(C6F5)4] resulted in low molecular weight polyisoprene (Mn< 2000) with hightrans-1,4-unit (>95%).Keywords:iminopyridine ligands;Fe(II);Co(II) complexes;isoprene polymerization;fluorinated aryl substituents
✓ 已验证
产品关联
DOI
PubMed
高影响因子
MATERIALS RESEARCH BULLETIN
·
2014
·
IF 1.968
Li-Ping Jia,Bing Yan
RE–Fe–B–Na (RE = Nd–Er) colloidal nanoparticles are prepared by high-temperature solution synthesis. These nanoparticles are ultra-small monodisperse, air-stable and amorphous, whose particle size and magnetic property are characterized by transmission electron microscope and superconducting quantum interference device. Taking Nd–Fe–B–Na nanoparticle as an example, it is found that the particle size can be controlled in less than 7 nm. Besides, the magnetic properties of RE–Fe–B–Na colloidal nanoparticles can be compared for different rare earth elements. Based on the bulk ferromagnetic coupling, other possible magnetic coupling mechanism is discussed.
✓ 已验证
产品关联
DOI
高影响因子
RSC Advances
·
2014
·Vol. 4
·期 88
·47615-47624
·
IF 3.708
Ping Li,Chunbo Liu,Guoling Wu,Yang Heng,Shuang Lin,Ao Ren,Kehan Lv,Lisong Xiao,Weidong Shi
In this paper, Fe-doped SrTiO3 (FSTO) photocatalysts were successfully prepared via a facile solvothermal method, and their photocatalytic activities for degrading tetracycline (TC) under visible light irradiation were examined. It was found that doping Fe3+ into the lattice of SrTiO3 resulted in the formation of new absorption bands in the visible light region, and the energy band gap decreased from 3.2 eV to 2.6 eV with Fe3+ doping amounts of 0 to 5 wt%. The photocatalytic experimental results indicated that the as-prepared FSTO photocatalysts generate an extremely high enhancement in the TC degradation ratio compared to the pure SrTiO3 under visible light irradiation. In particular, the FSTO sample doped with 3% Fe exhibited the highest TC degradation ratio (71.6%) in 80 min, which is mainly attributed to the narrowed gap generated by the appropriate level of Fe3+ doping. This work suggests that this doping method should be applicable for exploiting other efficient visible light-driven photocatalysts with wide band gap semiconductors.
✓ 已验证
产品关联
DOI
高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2015
·
IF 4.321
Zhouwei Miao,Xiaogang Gu,Shuguang Lu,Dionysios D. Dionysiou,Souhail R. Al-Abed,Xueke Zang,Xiaoliang Wu,Zhaofu Qiu,Qian Sui,Muhammad Danish
The performance of chelated Fe(II)-based catalyzed sodium percarbonate (SPC) stimulating the degradation of perchloroethylene (PCE) in aqueous solution was investigated using six different chelating agents (CA), namely, citric acid monohydrate (CIT), oxalic acid (OA), l -ascorbic acid (ASC), ethylenediaminetetraacetic acid (EDTA), trisodium citrate 2-hydrate (CIT-Na 3 ), and EDTA-Na 2 , at CA/Fe(II)/SPC/PCE molar ratios of 2/4/4/1, 4/4/4/1 and 8/4/4/1. The results indicated that the addition of CIT and OA significantly enhanced the PCE degradation. In addition, investigations using free radical probe compounds and radical scavengers revealed that PCE was primarily degraded by HO radical oxidation in Fe(II)/SPC, CIT/Fe(II)/SPC, and OA/Fe(II)/SPC systems and O 2 − also participated in the degradation of PCE in CIT/Fe(II)/SPC and OA/Fe(II)/SPC systems. The intensity of HO detected by electron paramagnetic resonance (EPR) in CIT/Fe(II)/SPC and OA/Fe(II)/SPC systems indicated that the addition of CIT or OA indeed enhanced the continuous production of HO and enabled the intensity of HO to be more stable. The results demonstrated that CIT and OA significantly improved the PCE degradation efficiency by increasing the concentration of Fe(II) and maintaining the concentration of HO radicals in solution. In conclusion, chelated Fe(II)-based catalyzed SPC oxidation process shows enormous practical prospects for the remediation of PCE-contaminated groundwater because of the effectiveness without pre-adjusting the solution pH and complete mineralization in Fe(II)/SPC, CIT/Fe(II)/SPC and OA/Fe(II)/SPC systems.
✓ 已验证
产品关联
DOI
高影响因子
ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH
·
2013
·Vol. 21
·期 2
·1401-1410
·
IF 2.618
Wu Xiaoliang,Lu Shuguang,Qiu Zhaofu,Sui Qian,Lin Kuangfei,Du Xiaoming,Luo Qishi
Most studies on the treatment of chlorinated contaminants by Fe(0) focus on aqueous system tests. However, few is known about the effectiveness of these tests for degrading chlorinated contaminants such as 1,1,1-trichloroethane (TCA) in soil. In this work, the reductive degradation performance of 1,1,1-TCA by Fe(0) was thoroughly investigated in a soil slurry system. The effects of various factors including acid-washed iron, the initial 1,1,1-TCA concentration, Fe(0) dosage, slurry pH, and common constituents in groundwater and soil such as Cl − , HCO 3
− , SO 4
2− , and NO 3
− anions and humic acid (HA) were evaluated. The experimental results showed that 1,1,1-TCA could be effectively degraded in 12 h for an initial Fe(0) dosage of 10 g L −1 and a soil/water mass ratio of 1:5. The soil slurry experiments showed two-stage degradation kinetics: a slow reaction in the first stage and a fast reductive degradation of 1,1,1-TCA in the second stage. The reductive degradation of 1,1,1-TCA was expedited as the mass concentration of Fe(0) increased. In addition, high pHs adversely affected the degradation of 1,1,1-TCA over a pH range of 5.4–8.0 and the reductive degradation efficiency decreased with increasing slurry pH. The initial 1,1,1-TCA concentration and the presence of Cl − and SO 4
2− anions had negligible effects. HCO 3
− anions had a accelerative effect on 1,1,1-TCA removal, and both NO 3
− and HA had inhibitory effects. A Cl − mass balance showed that the amount of Cl − ions released into the soil slurry system during the 1,1,1-TCA degradation increased with increasing reaction time, suggesting that the main degradation mechanism of 1,1,1-TCA by Fe(0) in a soil slurry system was reductive dechlorination with 1,1-DCA as the main intermediate. In conclusion, this study provides a theoretical basis for the practical application of the remediation of contaminated sites containing chlorinated solvent.
✓ 已验证
产品关联
DOI
PubMed
高影响因子
SPECTROCHIMICA ACTA PART A-MOLECULAR AND BIOMOLECULAR SPECTROSCOPY
·
2014
·
IF 2.129
Zhengjuan Sun,Yali Liu,Yuanfang Li
A novel and rapid spectrofluorometry method for the recognition of 6-mercaptopurine (6-MP) has been developed based on luminescent metal–organic frameworks Fe-MIL-88NH 2 as fluorescent probe. The strong fluorescence of Fe-MIL-88NH 2 at 430 nm could be quenched by 6-MP directly, and the Fe-MIL-88NH 2 shows high selectivity for 6-MP compared to other thiol-containing amino acids such as homocysteine (Hcy), cysteine (Cys), glutathione (GSH), etc. Under optimal conditions, the relative fluorescence intensity was linearly proportional to the concentration of 6-MP in the range of 5–600 μM with the detection limit at 1.17 μM (S/N = 3). Furthermore, the present approach has been successfully applied to the determination of 6-MP in human serum samples. The possible fluorescence quenching mechanism has also been investigated, where it is revealed that the quenching was attributed to competition of absorption of the light source energy as well as electron transfer between Fe-MIL-88NH 2 and 6-MP.
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Journal of Materials Chemistry A
·
2017
·Vol. 5
·期 34
·18071-18080
·
IF 8.867
Zhigao Zhu,Chenghan Ji,Lingling Zhong,Shuang Liu,Fuyi Cui,Hongliang Sun,Wei Wang
Porous carbonaceous materials are widely used as catalyst carriers to activate peroxymonosulfate (PMS) for catalytic oxidative degradation of organic pollutants. Herein, hierarchical structured ferro-cobalt alloyed crystals supported on nitrogen doped activated porous carbon fibers (FeCo2@APCFs) were prepared by a combination of multicomponent electrospinning, activation, and carbonization. Benefiting from the precursor design and activation process, the carbon fibers derived from a PAN/PBZ (polyacrylonitrile/polybenzoxazine) precursor exhibited a tunable porous structure with an ultrahigh specific surface area (SSA) and pore volume of 2085 m2 g−1 and 1.12 cm3 g−1, respectively. Most importantly, the FeCo2 crystals can be directly synthesized by carbonization at high temperature in a N2 flow with no other reducing gases. The as-prepared FeCo2@APCFs exhibited robust activation of PMS with reactive oxygen radicals (SO4˙−, ˙OH, and 1O2) for ultrafast removal of organic pollutants, as well as good stability and recyclability with high total organic carbon (TOC) removal. The catalyst suspended in aqueous solution after catalysis can be easily separated with an external magnet without tedious separation processes. This study is meaningful for the development of novel catalyst carriers or a fascinating strategy for wastewater treatment.
✓ 已验证
产品关联
DOI
高影响因子
Journal of Nanomaterials
·
2016
·
IF 1.758
Yongli Zhang,Shujuan Dai,Yanbo Zhou,Kai Lin
Fe-Co-Ce composite catalysts were prepared by coprecipitation method using CO(NH2)2, NaOH, NH4HCO3, and NH3·H2O as precipitant agents. The effects of the precipitant agents on the physicochemical properties of the Fe-Co-Ce based catalysts were investigated by SEM, TEM, BET, TG-DTA, and XRD. It was found that the precipitant agents remarkably influenced the morphology and particle size of the catalysts and affected the COD removal efficiency, decolorization rate, and pH of methyl orange for catalytic wet air oxidation (CWAO). The specific surface area of the Fe-Co-Ce composite catalysts successively decreased in the order of NH3·H2O, NH4HCO3, NaOH, and CO(NH2)2, which correlated to an increasing particle size that increased for each catalyst. For the CWAO of a methyl orange aqueous solutions, the effects of precipitant agents NH3·H2O and NaOH were superior to those of CO(NH2)2 and NH4HCO3. The catalyst prepared using NH3·H2O as the precipitant agent was mostly composed of Fe2O3, CoO, and CeO2. The COD removal efficiency of methyl orange aqueous solution for NH3·H2O reached 92.9% in the catalytic wet air oxidation. Such a catalytic property was maintained for six runs.
✓ 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）