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A novel Ag/ZnO core-shell structure for efficient sterilization synergizing antibiotics and subsequently removing residuals
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作者 Wenmei Han Wenli Wang +4 位作者 Jie Fan Runping Jia Xuchun Yang Tong Wu Qingsheng Wu 《Green Energy & Environment》 SCIE EI CAS CSCD 2024年第2期366-377,共12页
The massive use of antibiotics has led to the aggravation of bacterial resistance and also brought environmental pollution problems.This poses a great threat to human health.If the dosage of antibiotics is reduced by ... The massive use of antibiotics has led to the aggravation of bacterial resistance and also brought environmental pollution problems.This poses a great threat to human health.If the dosage of antibiotics is reduced by increasing its bactericidal performance,the emergence of drug resistance is certainly delayed,so that there's not enough time for developing drug resistance during treatment.Therefore,we selected typical representative materials of metal Ag and semiconductor ZnO nano-bactericides to design and synthesize Ag/ZnO hollow core-shell structures(AZ for short).Antibiotics are grafted on the surface of AZ through rational modification to form a composite sterilization system.The research results show that the antibacterial efficiency of the composite system is significantly increased,from the sum(34.7%+22.8%-57.5%)of the antibacterial efficiency of AZ and gentamicin to 80.2%,net synergizes 22.7%,which fully reflects the effect of 1+1>2.Therefore,the dosage of antibiotics can be drastically reduced in this way,which makes both the possibility of bacterial resistance and medical expenses remarkably decrease.Subsequently,residual antibiotics can be degraded under simple illumination using AZ-self as a photocatalyst,which cuts off the path of environmental pollution.In short,such an innovative route has guiding significance for drug resistance. 展开更多
关键词 Ag/ZnO hollow core-shell structures ANTIBIOTICS GENTAMYCIN Synergistic sterilization PHOTODEGRADATION
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Exploring the Core-shell Structure of BaTiO3-based Dielectric Ceramics Using Machine Learning Models and Interpretability Analysis
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作者 孙家乐 XIONG Peifeng +1 位作者 郝华 LIU Hanxing 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS CSCD 2024年第3期561-569,共9页
A machine learning(ML)-based random forest(RF)classification model algorithm was employed to investigate the main factors affecting the formation of the core-shell structure of BaTiO_(3)-based ceramics and their inter... A machine learning(ML)-based random forest(RF)classification model algorithm was employed to investigate the main factors affecting the formation of the core-shell structure of BaTiO_(3)-based ceramics and their interpretability was analyzed by using Shapley additive explanations(SHAP).An F1-score changed from 0.8795 to 0.9310,accuracy from 0.8450 to 0.9070,precision from 0.8714 to 0.9000,recall from 0.8929 to 0.9643,and ROC/AUC value of 0.97±0.03 was achieved by the RF classification with the optimal set of features containing only 5 features,demonstrating the high accuracy of our model and its high robustness.During the interpretability analysis of the model,it was found that the electronegativity,melting point,and sintering temperature of the dopant contribute highly to the formation of the core-shell structure,and based on these characteristics,specific ranges were delineated and twelve elements were finally obtained that met all the requirements,namely Si,Sc,Mn,Fe,Co,Ni,Pd,Er,Tm,Lu,Pa,and Cm.In the process of exploring the structure of the core-shell,the doping elements can be effectively localized to be selected by choosing the range of features. 展开更多
关键词 machine learning BaTiO_(3) core-shell structure random forest classifier
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Fabricating Core-Shell WC@C/Pt Structures and its Enhanced Performance for Methanol Electrooxidation 被引量:1
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作者 陈赵扬 段隆发 +3 位作者 褚有群 盛江峰 林文锋 马淳安 《Chinese Journal of Chemical Physics》 SCIE CAS CSCD 2017年第4期450-456,I0002,共8页
The spray-dried spheres within a W/Pt multi-separation can be used to prepare discrete core-shell WC@C/Pt catalysts through a typical carburization production mechanism at 800 ℃. In contrast with previous studies of ... The spray-dried spheres within a W/Pt multi-separation can be used to prepare discrete core-shell WC@C/Pt catalysts through a typical carburization production mechanism at 800 ℃. In contrast with previous studies of the WC/Pt synthesis, the reaction observed here proceeds through an indirect annealing thereby resulting in core-shell structure, and mechanism at 600℃ wherein species diffuse, Pt nanoparticles were successfully dispersed in size/shape and randomly scattered across the in situ produced C spheres. Through direct carburization or at higher initial hydrochloroplatiuic acid concentrations, however, complete reaction with core-shell spheres was not observed. Indirect carburization reduces the strain felt by the bonds featuring the larger WC WC and Pt nanoparticles to be reserved, stability toward methanol oxidation. particles and allows the motion of carbon around influencing the eleetrocatalytic performance and 展开更多
关键词 Self-disperse core-shell structure Carbon-resist Tungsten carbide Methanol oxidation
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Recent advances in core-shell organic framework-based photocatalysts for energy conversion and environmental remediation
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作者 Qibing Dong Ximing Li +9 位作者 Yanyan Duan Qingyun Tian Xinxin Liang Yiyin Zhu Lin Tian Junjun Wang Atif Sial Yongqian Cui Ke Zhao Chuanyi Wang 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第8期168-199,I0004,共33页
Direct conversion of solar energy into chemical energy in an environmentally friendly manner is one of the most promising strategies to deal with the environmental pollution and energy crisis.Among a variety of materi... Direct conversion of solar energy into chemical energy in an environmentally friendly manner is one of the most promising strategies to deal with the environmental pollution and energy crisis.Among a variety of materials developed as photocatalysts,the core-shell metal/covalent-organic framework(MOF or COF)photocatalysts have garnered significant attention due to their highly porous structure and the adjustability in both structure and functionality.The existing reviews on core-shell organic framework photocatalytic materials have mainly focused on core-shell MOF materials.However,there is still a lack of indepth reviews specifically addressing the photocatalytic performance of core-shell COFs and MOFs@COFs.Simultaneously,there is an urgent need for a comprehensive review encompassing these three types of core-shell structures.Based on this,this review aims to provide a comprehensive understanding and useful guidelines for the exploration of suitable core-shell organic framework photocatalysts towards appropriate photocatalytic energy conversion and environmental governance.Firstly,the classification,synthesis,formation mechanisms,and reasonable regulation of core-shell organic framework were summarized.Then,the photocatalytic applications of these three kinds of core-shell structures in different areas,such as H_(2)evolution,CO_(2)reduction,and pollutants degradation are emphasized.Finally,the main challenges and development prospects of core-shell organic framework photocatalysts were introduced.This review aims to provide insights into the development of a novel generation of efficient and stable core-shell organic framework materials for energy conversion and environmental remediation. 展开更多
关键词 Organic framework core-shell structure PHOTOCATALYSIS Energy conversion Environmental remediation
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Mitigating Lattice Distortion of High‑Voltage LiCoO_(2)via Core‑Shell Structure Induced by Cationic Heterogeneous Co‑Doping for Lithium‑Ion Batteries
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作者 Zezhou Lin Ke Fan +9 位作者 Tiancheng Liu Zhihang Xu Gao Chen Honglei Zhang Hao Li Xuyun Guo Xi Zhang Ye Zhu Peiyu Hou Haitao Huang 《Nano-Micro Letters》 SCIE EI CSCD 2024年第3期169-182,共14页
Inactive elemental doping is commonly used to improve the structural stability of high-voltage layered transition-metal oxide cathodes.However,the one-step co-doping strategy usually results in small grain size since ... Inactive elemental doping is commonly used to improve the structural stability of high-voltage layered transition-metal oxide cathodes.However,the one-step co-doping strategy usually results in small grain size since the low diffusivity ions such as Ti^(4+)will be concentrated on grain boundaries,which hinders the grain growth.In order to synthesize large single-crystal layered oxide cathodes,considering the different diffusivities of different dopant ions,we propose a simple two-step multi-element co-doping strategy to fabricate core–shell structured LiCoO_(2)(CS-LCO).In the current work,the high-diffusivity Al^(3+)/Mg^(2+)ions occupy the core of single-crystal grain while the low diffusivity Ti^(4+)ions enrich the shell layer.The Ti^(4+)-enriched shell layer(~12 nm)with Co/Ti substitution and stronger Ti–O bond gives rise to less oxygen ligand holes.In-situ XRD demonstrates the constrained contraction of c-axis lattice parameter and mitigated structural distortion.Under a high upper cut-off voltage of 4.6 V,the single-crystal CS-LCO maintains a reversible capacity of 159.8 mAh g^(−1)with a good retention of~89%after 300 cycles,and reaches a high specific capacity of 163.8 mAh g^(−1)at 5C.The proposed strategy can be extended to other pairs of low-(Zr^(4+),Ta^(5+),and W6+,etc.)and high-diffusivity cations(Zn^(2+),Ni^(2+),and Fe^(3+),etc.)for rational design of advanced layered oxide core–shell structured cathodes for lithium-ion batteries. 展开更多
关键词 Lithium-ion battery LiCoO_(2) Heterogeneous co-doping core-shell structure High-voltage stability
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Interfacial reinforcement of core-shell HMX@energetic polymer composites featuring enhanced thermal and safety performance
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作者 Binghui Duan Hongchang Mo +3 位作者 Bojun Tan Xianming Lu Bozhou Wang Ning Liu 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2024年第1期387-399,共13页
The weak interface interaction and solid-solid phase transition have long been a conundrum for 1,3,5,7-tetranitro-1,3,5,7-tetraazacyclooctane(HMX)-based polymer-bonded explosives(PBX).A two-step strategy that involves... The weak interface interaction and solid-solid phase transition have long been a conundrum for 1,3,5,7-tetranitro-1,3,5,7-tetraazacyclooctane(HMX)-based polymer-bonded explosives(PBX).A two-step strategy that involves the pretreatment of HMX to endow—OH groups on the surface via polyalcohol bonding agent modification and in situ coating with nitrate ester-containing polymer,was proposed to address the problem.Two types of energetic polyether—glycidyl azide polymer(GAP)and nitrate modified GAP(GNP)were grafted onto HMX crystal based on isocyanate addition reaction bridged through neutral polymeric bonding agent(NPBA)layer.The morphology and structure of the HMX-based composites were characterized in detail and the core-shell structure was validated.The grafted polymers obviously enhanced the adhesion force between HMX crystals and fluoropolymer(F2314)binder.Due to the interfacial reinforcement among the components,the two HMX-based composites exhibited a remarkable increment of phase transition peak temperature by 10.2°C and 19.6°C with no more than 1.5%shell content,respectively.Furthermore,the impact and friction sensitivity of the composites decreased significantly as a result of the barrier produced by the grafted polymers.These findings will enhance the future prospects for the interface design of energetic composites aiming to solve the weak interface and safety concerns. 展开更多
关键词 HMX crystals Polyalcohol bonding agent Energetic polymer core-shell structure Interfacial reinforcement
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Fabrication of Core-Shell Hydrogel Bead Based on Sodium Alginate and Chitosan for Methylene Blue Adsorption
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作者 Xiaoyu Chen 《Journal of Renewable Materials》 EI CAS 2024年第4期815-826,共12页
A novel core-shell hydrogel bead was fabricated for effective removal of methylene blue dye from aqueous solutions.The core,made of sodium alginate-g-polyacrylamide and attapulgite nanofibers,was cross-linked by Calci... A novel core-shell hydrogel bead was fabricated for effective removal of methylene blue dye from aqueous solutions.The core,made of sodium alginate-g-polyacrylamide and attapulgite nanofibers,was cross-linked by Calcium ions(Ca^(2+)).The shell,composed of a chitosan/activated carbon mixture,was then coated onto the core.Fourier transform infrared spectroscopy confirmed the grafting polymerization of acrylamide onto sodium alginate.Scanning electron microscopy images showed the core-shell structure.The core exhibited a high water uptake ratio,facilitating the diffusion of methylene blue into the core.During the diffusion process,the methylene blue was first adsorbed by the shell and then further adsorbed by the core.Adsorption tests showed that the coreshell structure had a larger adsorption capacity than the core alone.The shell effectively enhanced the adsorption capacity to methylene blue compared to the single core.Methylene blue was adsorbed by activated carbon and chitosan in the shell,and the residual methylene blue diffused into the core and was further adsorbed. 展开更多
关键词 core-shell structure hydrogel bead attapulgite nanofiber sodium alginate POLYACRYLAMIDE methylene blue adsorption material
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Synthesis and Characterization of Fluorine-containing Polyacrylate Emulsion with Core-Shell Structure 被引量:29
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作者 肖新颜 刘健飞 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2008年第4期626-630,共5页
A fluorine-containing polyacrylate copolymer emulsion was synthesized by a seed emulsion polymerization method, in which methyl methacrylate (MMA) and butyl acrylate (BA) were used as main monomers and hexafluorob... A fluorine-containing polyacrylate copolymer emulsion was synthesized by a seed emulsion polymerization method, in which methyl methacrylate (MMA) and butyl acrylate (BA) were used as main monomers and hexafluorobutyl methacrylate (HFMA) as fluorine-containing monomer. The structure and properties were characterized by Fourier transform infrared spectrum (FT-IR), transmission electron microscopy (TEM), particle size analysis, X-ray photoelectron spectroscopy (XPS), contact angle (CA), differential scanning calorimetry (DSC) and thermogravimetry (TG) analysis. The FTIR and TEM results showed that HFMA was effectively involved in the emulsion copolymerization, and the formed emulsion particles had a core-shell structure and a narrow particle size distribution. XPS and CA analysis revealed that a gradient concentration of fluorine existed in the depth profile of fluorine-containing emulsion film which was richer in fluorine and more hydrophobic in one side. DSC and TG analysis also showed that a clear core-shell structure existed in the fluorine-containing emulsion particles, and their film showed higher thermal stability than that of fluorine-free emulsion. 展开更多
关键词 fluorine-containing polyacrylate emulsion core-shell structure seed emulsion polymerization
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PREPARATION OF ACRYLIC SUPERABSORBENTS WITH CORE-SHELL STRUCTURE BY MODIFIED INVERSE SUSPENSION POLYMERIZATION 被引量:10
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作者 崔英德 郭建维 +1 位作者 廖列文 尹国强 《化工学报》 EI CAS CSCD 北大核心 2000年第6期723-724,共2页
关键词 SUPERABSORBENTS core-shell structure inverse suspension
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Synthesis of core-shell nanostructured Cr2O3/C@TiO2 for photocatalytic hydrogen production 被引量:6
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作者 Yang Chen Guobing Mao +4 位作者 Yawen Tang Heng Wu Gang Wang Li Zhang Qi Liu 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 2021年第1期225-234,共10页
In this study,the Cr2O3/C@TiO2 composite was synthesized via the calcination of yolk–shell MIL-101@TiO2.The composite presented core–shell structure,where Cr-doped TiO2 and Cr2O3/C were the shell and core,respective... In this study,the Cr2O3/C@TiO2 composite was synthesized via the calcination of yolk–shell MIL-101@TiO2.The composite presented core–shell structure,where Cr-doped TiO2 and Cr2O3/C were the shell and core,respectively.The introduction of Cr^3+and Cr2O3/C,which were derived from the calcination of MIL-101,in the composite enhanced its visible light absorbing ability and lowered the recombination rate of the photogenerated electrons and holes.The large surface area of the Cr2O3/C@TiO2 composite provided numerous active sites for the photoreduction reaction.Consequently,the photocatalytic performance of the composite for the production of H2 was better than that of pure TiO2.Under the irradiation of a 300 W Xe arc lamp,the H2 production rate of the Cr2O3/C@TiO2 composite that was calcined at 500°C was 446μmol h−1 g−1,which was approximately four times higher than that of pristine TiO2 nanoparticles.Moreover,the composite exhibited the high H2 production rate of 25.5μmol h−1 g−1 under visible light irradiation(λ>420 nm).The high photocatalytic performance of Cr2O3/C@TiO2 could be attributed to its wide visible light photoresponse range and efficient separation of photogenerated electrons and holes.This paper offers some insights into the design of a novel efficient photocatalyst for water-splitting applications. 展开更多
关键词 core-shell structure CR2O3 TIO2 Hydrogen generation PHOTOCATALYST
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Effect of milling process on the core-shell structures and dielectric properties of fine-grained BaTiO_3-based X7R ceramic materials 被引量:3
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作者 Tian Wang Xiao-hui Wang Hai Wen Long-tu Li 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2009年第3期345-348,共4页
Fine-grained BaTiO3-based X7R ceramic materials were prepared and the effects of milling process on the core-shell structures and dielectric properties were investigated using scanning electron microscope, transmissio... Fine-grained BaTiO3-based X7R ceramic materials were prepared and the effects of milling process on the core-shell structures and dielectric properties were investigated using scanning electron microscope, transmission electron microscope, and energy dispersive spectroscopy (EDS). As the milling time extends, the dielectric constant of the ceramics increases, whereas the temperature coefficient of capacitance at 125℃ drops quickly. The changes in dielectric properties are considered relevant to the microstructure evolution caused by the milling process. Defects on the surface of BaTiO3 particles increase because of the effects of milling process, which will make it easier for additives to diffuse into the interior grains. As the milling time increases, the shell region gets thicker and the core region gets smaller; however, EDS results show that the chemical inhomogeneity between grain core and grain shell becomes weaker. 展开更多
关键词 fine-grain barium titanate core-shell structure milling process microstructure CAPACITOR
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Synthesis of Ag@Al_2O_3 Core-shell Structure Nanoparticles and Their Enhancement Effect on Dielectric Properties for Ag@Al_2O_3/Polyimide Nanocomposites 被引量:2
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作者 翁凌 YAN Liwen +2 位作者 LI Hongxia XIA Qianshan LIU Lizhu 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 2015年第1期47-50,共4页
A novel core-shell structure Ag@Al2O3 nano-particles were synthesized and doped into polyimide as conductive fillers to prepare the composite films with high dielectric properties and low dielectric loss. The morpholo... A novel core-shell structure Ag@Al2O3 nano-particles were synthesized and doped into polyimide as conductive fillers to prepare the composite films with high dielectric properties and low dielectric loss. The morphology and structures of the Ag@Al2O3 nano-particles were characterized by transmission electron microscopy (TEM), X-ray diffraction (XRD), and UV-visible spectroscopy. All the results proved that the Ag@Al2O3 nano-parficles had a typical core-shell structure, for the Ag particles were coated by Al2O3 shell and the average sizes ofAg@Al2O3 particles were between 30 to 150 nm. The as-prepared Ag@Al2O3 nanoparticles were doped into the polyimide with different mass fractions to fabricate the Ag@Al2O3/PI composite films via in-situ polymerization process. SEM analysis of composite films showed that the Ag@Al2O3 nano- particles homogeneously dispersed in polyimide matrix with nanoseale. As dielectric materials for electronic packaging systems, the Ag@Al2O3/PI composites exhibited appropriate mechanical properties and erthaneed dielectric properties, including greatly enhanced dielectric constant and just a slight increase in dielectric loss. These improvements were attributed to the core-shell structure of fillers and their fine dispersion in the PI matrix. 展开更多
关键词 core-shell structure POLYIMIDE NANOCOMPOSITES dielectrics
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Core-shell structured 1,4-benzoquinone@TiO_2 cathode for lithium batteries 被引量:3
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作者 Aikai Yang Xingchao Wang +3 位作者 Yong Lu Licheng Miao Wei Xie Jun Chen 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2018年第6期1644-1650,共7页
Organic carbonyl compounds are considered as promising candidates for lithium batteries due to theirhigh capacity and environmental friendliness, However, they suffer from serious dissolution in the elec-trolyte, lead... Organic carbonyl compounds are considered as promising candidates for lithium batteries due to theirhigh capacity and environmental friendliness, However, they suffer from serious dissolution in the elec-trolyte, leading to fast capacity decay. Here we report core-shell structured 1,4-benzoquinone@titaniumdioxide (BQ@TiO2) composite as cathode for lithium batteries. The composite cathode can deliver a highdischarge capacity of 441.2 mA h/g at 50 mA/g and a high capacity retention of 80.7% after 100 cycles. Thegood cycling performance of BQ@TiO2 composite can be attributed to the suppressed dissolution of BQ,which results from the physical confinement effect of Ti02 shell and the strong interactions between BQand Ti02. Moreover, the combination of ex situ infrared spectra and density functional theory calculationsreveals that the active redox sites of BQ are carbonyl groups. This work provides an alternative way tomitigate the dissolution of small carbonyl compounds and thus enhance their cycling stability. 展开更多
关键词 Lithium batteries Organic cathode BENZOQUINONE Titanium dioxide core-shell structure Density functional theory
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The Structure and Size-effect of Calcium Modified Lead Titanate Nanocrystal,Pb_(0.85)Ca_(0.15)TiO_3 被引量:1
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作者 FU Honggang QIANG Liangsheng +5 位作者 XU Chongquan ZHAN Zhiqian ZHANG Xin YU Haitao ZHANG Yanxi HUANG Li 《Chemical Research in Chinese Universities》 SCIE CAS CSCD 1999年第2期66-70,共5页
Calcium modified lead titanate nanocrystal material Pb0.85Ca0.15TiO3 was synthesized by means of a solgel method.The changes of crystal structure and grainsize of the samples were investigated under different conditio... Calcium modified lead titanate nanocrystal material Pb0.85Ca0.15TiO3 was synthesized by means of a solgel method.The changes of crystal structure and grainsize of the samples were investigated under different conditions of heat treatment.the results show that the tetragonal symmetry is reduced and the ferroelectricparaelectric phase transformation temperature is decreased with the reduce of the grainsize of the sample.the critical grainsize for the ferroelectricparaelectric phase transformation at room temperature was calculated.The change regularities of the lattice constant and tetragonality with the grainsize are discussed. 展开更多
关键词 PTC15 nanocrystal Crystal structure Size effect Crystal structure Size effect
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Shell-driven Fine Structure Transition of Core Materials in Co@Au Core-shell Nanoparticles 被引量:1
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作者 Yujun Song Yinghui Wang +1 位作者 Shaoxia Ji Jie Ding 《Nano-Micro Letters》 SCIE EI CAS 2012年第4期235-242,共8页
Co@Au core shell nanoparticles(NPs) of different shell thicknesses were fabricated by a combination of the displacement process and the reduction-deposition process in a microfluidic reactor. The effect of the shell t... Co@Au core shell nanoparticles(NPs) of different shell thicknesses were fabricated by a combination of the displacement process and the reduction-deposition process in a microfluidic reactor. The effect of the shell thickness on the fine structures(local atom arrangement) of core materials was investigated by X-ray Absorption Near Edge Structure(XANES) and Extended X-ray Absorption Fine Structure(EXAFS).The results indicate that the shell thickness affects the fine structure of the core materials by causing atomic re-arrangement between the hexagonal close pack(hcp) and the face centered cubic(fcc) structure, and forming Co-Au bonds in the core-shell interface. 展开更多
关键词 NANOPARTICLE core-shell Fine structure Microfluidic
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Preparation of Self-crosslinked Fluorocarbon Polymer Emulsion with Core-shell Structure by the Method of Soap-free Emulsion Polymerization 被引量:1
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作者 陈立军 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 2009年第4期631-636,共6页
Using methyl methacrylate (MMA), butyl acrylate(BA) and hexafluorobutyl acrylate(HFBA) as main raw materials, we prepared self-crosslinked fluorocarbon polymer emulsion with core-shell structure via soap-free em... Using methyl methacrylate (MMA), butyl acrylate(BA) and hexafluorobutyl acrylate(HFBA) as main raw materials, we prepared self-crosslinked fluorocarbon polymer emulsion with core-shell structure via soap-free emulsion polymerization when the conception of particle design and polymer morphology was adopted. Moreover, the influence of mole ratio of BA to MAA, pH value on the oligomer was studied. And the effects of the added amount of oligomer, self-crosslinked monomer and HFBA, mass ratio of BA to MMA, reaction temperature and the initiator on the polymerization technology and the performance of the product, were investigated and optimized. The structure and performance of the fluorocarbon polymer emulsion were characterized and tested with FTIR, TEM, MFT and contact angle and water absorption of the latex film. The experimental results show that the optimal conditions for preparing fluorocarbon polymer emulsion are as follows: for preparing the oligomer, tool ratio of BA to MAA is equal to 1.0 : 1.60, and pH value is controlled within the range of 8.0 and 9.0; for preparing fluorocarbon polymer emulsion, the added amount of oligmer[P(BA/MANa)] is 6%; mass ratio of BA to MMA is 40 " 60; the added amount of self-crosslinked monomer is 2%, the added amount of HFBA is 15 %; reaction temperature is 80 ℃; the mixture of potassium persulfate and sodium bisulfite is used as the initiator. The film-forming stability of the fluorocarbon polymer emul- sion and the performance of the latex film, which is prepared with the soap-free emulsion polymerization, are better than that prepared with the conventional emulsion polymerization. 展开更多
关键词 soap-free emulsion polymerization core-shell structure self-crosslinkage fluorocarbon polymer emulsion
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Synthesis of carbon-coated cobalt ferrite core-shell structure composite:A method for enhancing electromagnetic wave absorption properties by adjusting impedance matching 被引量:1
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作者 Jing Gao Zhijun Ma +1 位作者 Fuli Liu Cunxin Chen 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2022年第7期206-217,共12页
Cobalt ferrite has problems such as poor impedance matching and high density,which results in unsatisfactory electromagnetic wave(EMW)absorption performance.In this study,the CoFe_(2)O_(4)@C core-shell structure compo... Cobalt ferrite has problems such as poor impedance matching and high density,which results in unsatisfactory electromagnetic wave(EMW)absorption performance.In this study,the CoFe_(2)O_(4)@C core-shell structure composite was synthesized by a two-step hydrothermal method.X-ray diffraction,transmission electron microscopy,Fourier transform infrared spectroscopy,thermogravimetric analysis,and vector network analysis et al.were used to test the structure and EMW absorption properties of CoFe_(2)O_(4)@C composite.The results show that the reflection loss(RL)of the CoFe_(2)O_(4)@C composite reaches the maximum value of25.66 dB at 13.92 GHz,and the effective absorbing band(EAB)is 4.59 GHz(11.20-15.79 GHz)when the carbon mass content is 6.01%.The RL and EAB of CoFe_(2)O_(4)@C composite are increased by 219.55%and 4.59 GHz respectively,and the density is decreased by 20.78%compared with the cobalt ferrite.Such enhanced EMW absorption properties of CoFe_(2)O_(4)@C composite are attributed to the attenuation caused by the strong natural resonance of the cobalt ferrite,moreover,the carbon coating layer adjusts the impedance matching of the composite,and the introduced dipole polarization and interface polarization can cause multiple Debye relaxation processes. 展开更多
关键词 Cobalt ferrite core-shell structure composite Electromagnetic wave absorption Impedance matching
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Preparation and Properties of Polyurethane/Nickel Nanofiber with Core-Shell Structure Using Coaxial Electrospinning Method 被引量:1
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作者 FU Shaoju ZENG Pei +1 位作者 HOU Xuemei ZHAN Jianchao 《Journal of Donghua University(English Edition)》 CAS 2021年第2期114-117,共4页
Nanofiber has been widely used in numerous fields for its good advantages such as large surface area and porosity.However,the relationship between nanofiber structure and coaxial electrospinning process is still not c... Nanofiber has been widely used in numerous fields for its good advantages such as large surface area and porosity.However,the relationship between nanofiber structure and coaxial electrospinning process is still not clear and deserved to be studied.In this work,a kind of polyurethane/nickel(PU/Ni)nanofiber with core-shell structures was developed,and the effects of electrospinning parameters on the properties of nanofiber were evaluated.The results showed that the optimized parameters of core-shell electrospinning speeds were 1 mL/h(core)and 1 mL/h(shell),respectively.Sample c with the core-shell electrospinning speed ratio of 1∶1,exhibited the relatively smooth surface,good orientation,and bonding points.It also had the largest tensile strength at 99 cN,tensile elongation at 44.86%,and the best electricity conductivity,which showed great potential in the application of nanofiber fields. 展开更多
关键词 NANOFIBER surface area POROSITY core-shell structure electrospinning speed
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Application of Monodisperse Thermo-Responsive Composite Microgels with Core-Shell Structure Based on Au@Ag Bimetallic Nanorod as Core in Surface Enhanced Raman Spectroscopy Substrate 被引量:1
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作者 董旭 陈思远 査刘生 《Journal of Donghua University(English Edition)》 EI CAS 2016年第1期112-116,共5页
The monodisperse Au@Ag bimetallic nanorod is encapsulated by crosslinked poly( N-isopropylacrylamide)( PNIPAM) to produce thermo-responsive composite microgel with well-defined core-shell structure( Au@ Ag NR@ PNIPAM ... The monodisperse Au@Ag bimetallic nanorod is encapsulated by crosslinked poly( N-isopropylacrylamide)( PNIPAM) to produce thermo-responsive composite microgel with well-defined core-shell structure( Au@ Ag NR@ PNIPAM microgel)by seed-precipitation polymerization method using butenoic acid modified Au @ Ag NRs as seeds. When the temperature of the aqueous medium increases from 20℃ to 50℃,the localized surface plasmon resonance( LSPR) band of the entrapped Au @ Ag NR is pronouncedly red-shifted because of the decreased spatial distances between them as a result of shrinkage of the microgels,leading to their plasmonic coupling. The temperature tunable plasmonic coupling is demonstrated by temperature dependence of the surface enhanced Raman spectroscopy( SERS) signal of 1-naphthol in aqueous solution. Different from static plasmonic coupling modes from nanostructured assembly or array system of noble metals,the proposed plasmonic coupling can be dynamically controlled by environmental temperature. Therefore, the thermo responsive hybrid microgels have potential applications in mobile LSPR or SERS microsensors for living tissues or cells. 展开更多
关键词 smart composite microgels core-shell structure Au@Ag bimetallic nanorods thermo-responsiveness surface enhanced Raman spectroscopy(SERS)
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Immobilization of metalloporphyrins on CeO_2@SiO_2 with a core-shell structure prepared via microemulsion method for catalytic oxidation of ethylbenzene 被引量:1
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作者 沈丹华 吉琳韬 +4 位作者 付玲玲 董旭龙 刘志刚 刘强 刘世明 《Journal of Central South University》 SCIE EI CAS CSCD 2015年第3期862-867,共6页
Ce O2@Si O2 core-shell nanoparticles were prepared by microemulsion method, and metalloporphyrins were immobilized on the Ce O2@Si O2 core-shell nanoparticles surface via amide bond. The supported metalloporphyrin cat... Ce O2@Si O2 core-shell nanoparticles were prepared by microemulsion method, and metalloporphyrins were immobilized on the Ce O2@Si O2 core-shell nanoparticles surface via amide bond. The supported metalloporphyrin catalysts were characterized by N2 adsorption-desorption isotherm(BET), scanning electron microscopy(SEM), transmission electron microscopy(TEM), X-ray diffraction(XRD), ultraviolet and visible spectroscopy(UV-Vis), and Fourier transform infrared spectroscopy(FT-IR). The results show that the morphology of Ce O2@Si O2 nanoparticles is core-shell microspheres with about 30 nm in diameter, and metalloporphyrins are immobilized on the Ce O2@Si O2 core-shell nanoparticles via amide bond. Especially, the core-shell structure contains multi Ce O2 core and thin Si O2 shell, which may benefit the synergistic effect between the Ce O2 core and the porphyrin anchored on the very thin Si O2 shell. As a result, this supported metalloporphyrin catalysts present comparably high catalytic activity and stability for oxidation of ethylbenzene with molecular oxygen, namely, ethylbenzene conversion remains around 12% with identical selectivity of about 80% for acetophenone even after six-times reuse of the catalyst. 展开更多
关键词 Ce O2@Si O2 core-shell structure metalloporphyrin ethylbenzene oxidation
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