Materials Today Communications
·
2023
·
IF 3.8
Guangyin Liu,Jun Shen,Qin Tang,Hao Li,Chaofan Ma,Yuhui Zhang
Cu nano/microparticle pastes have garnered considerable research interest and investigation for their application in the packaging of power devices. However, their inherent porosity negatively affects joint performance. In this study, we addressed the issue of porosity in Cu-Cu joints by incorporating a liquid metal (LM) into a Cu nano/microparticle paste solder. The LM exhibits wettability and flowability , enabling it to spontaneously fill the pores in the Cu nano/microparticle structure and establish connections with the substrate surface. Moreover, the LM creates additional conductive pathways and reduces thermal resistance, resulting in enhanced electrical and thermal conductivities . The experimental thermal conductivity reached an impressive value of 342.68 W/(m·K), while the observed electrical resistivity was as low as 6.16 μΩ·cm. These findings demonstrate the positive effect of LM on Cu-Cu joints and offer a novel theoretical foundation for improving the electrical and mechanical properties of such joints.
研究领域:
材料科学
·
电子封装技术
✓ 已验证
产品关联
DOI
高影响因子
ACS Omega
·
2019
·
IF 2.584
Simin Cui,Xianglei He,Dan Wang,Jie-Xin Wang,Yuan Pu,Jian-Feng Chen
The ideal product of rare-earth-doped phosphors should have uniform particle size distribution and homogeneous doping ions in each particle, and therefore, intensified micromixing at mesoscale is highly required. In this article, inspired by the concept of “mesoscience”, we demonstrate the tuning of Eu3+ doping in GdBO3 microparticles at mesoscale by a high-gravity-assisted reactive precipitation-coupled calcination process. The high-gravity environment and tiny droplets generated by the high-gravity rotating packed bed (RPB) reactor lead to significant intensification of mass transfer and micromixing, which are beneficial for the homogeneous doping of Eu3+ in the host material during reactive precipitation in liquid solution. Under excitation at 395 nm, the emission spectra of the Eu3+-doped phosphors exhibit a narrow-band red emission centered at 625 nm and the highest intensity was observed at x = 0.2. The RPB products show higher intensity than that of the control group even when the reaction time was shortened to 1/6. After calculation, the quenching in the sample most likely results from dipole–dipole interactions. The chromaticity coordinates for the RPB sample was measured as (0.598, 0.341) with a quantum yield of up to 78.11%, and the phosphors exhibit good thermal stability at 423 K. The phosphors were used as the luminescent materials for light-emitting diodes (LEDs), and the devices showed good performance. Our preliminary study illustrated that high-gravity-assisted approaches are promising for tuning the doping of rare-earth ions in microparticles at mesoscale toward efficient production of phosphors for LEDs.
研究领域:
材料科学
·
发光材料
·
纳米技术
✓ 已验证
产品关联
DOI
PubMed
高影响因子
JOURNAL OF PETROLEUM SCIENCE AND ENGINEERING
·
2017
·
IF 1.873
Shuanglei Peng,Guancheng Jiang,Xinliang Li,Lili Yang,Fan Liu,Yinbo He
During the process of recirculating drilling fluids, the removal of useless solids, especially submicron particles, in drilling fluids is the most problematic issue in drilling operations. The cost and efficiency of currently used technologies are the two issues that have to be addressed urgently. In this study, the novel flocculant CMC- g -DMDAAC was synthesized by grafting diallyl dimethyl ammonium chloride (DMDAAC) onto carboxymethyl chitosan (CMC). The physicochemical structure of the CMC- g -DMDAAC product was characterized by Fourier-transform infrared (FT-IR) spectroscopy, proton nuclear magnetic resonance ( 1 H NMR) spectroscopy, and determination of the ζ-potential. A kaolinite suspension, a bentonite suspension, and drilling fluids from an oilfield were selected to evaluate the flocculation performance of CMC- g -DMDAAC by testing the products’ turbidities and particle size distributions. In comparison, the flocculation performances of chitosan, CMC, and commercial hydrolyzed polyacrylamide (HPAM) were also tested under the same conditions. The results showed that CMC- g -DMDAAC exhibited steady flocculation performances for all clay suspensions and drilling fluids at all pH ranges at low dosage. The scavenging capacity of submicron particles in drilling fluids was also excellent for the tested product.
研究领域:
化学工程
·
材料科学
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF ALLOYS AND COMPOUNDS
·
2018
·
IF 3.779
Shun Dong,Wenzheng Zhang,Ping Hu,Yumin Zhang,Jiecai Han,Xiaoguang Luo
Nitrogen-doped SiC microparticles (SiCp) and SiC nanowries (SiCNWs) with different nitrogen contents were successfully synthesized by a simple and effective method, in which SiCp and SiCNWs were directly annealed in N 2 at 1500 °C with different holding times to adjust the contents of nitrogen for the first time. The nitrogen content of N-doped SiCp and SiCNWs increased with holding time, from 2.91 at.% and 3.05 at.% for 1 h to 5.05 at.% and 5.25 at.% for 4 h. The size of N-doped SiCp and SiCNWs was larger than that of pristine SiCp and SiCNWs, while the size tended to increase firstly and then decrease. The results of dielectric parameters showed that both real part ε′ and imaginary part ε ″ of permittivity of the samples increased greatly with increasing N contents in most frequency range, while two opposing trends for nitrogen content dependent microwave absorption property of N-doped SiCp and SiCNWs were observed. The electromagnetic (EM) wave absorption capability of N-doped SiCp was significantly improved with increasing nitrogen content compared with fully permeable wave pristine SiCp, and the minimum reflection loss (RL m ) and maximum effective absorption bandwidth (EAB) could be up to −33.5 dB and 4.4 GHz, respectively. The EM wave absorption performance of N-doped SiCNWs exhibited a decreasing tendency with increasing nitrogen content, and the RL m was decreased from −57 dB for pristine SiCNWs, to −51.2 dB for SiCNWs with 3.05 at.% N, and to −29.3 dB for SiCNWs with 5.25 at.% N. Moreover, if the experimental process in present study was decomposed into heat-treatment and N-doping, the heat-treatment played extremely negative effect on the EM wave absorption performance of samples, while N-doping still had positive impact on the EM wave absorption performance. It is believed that the current work will provide a new insight into the fabrication of SiC materials with fascinating properties by doping.
研究领域:
材料科学
·
电磁学
✓ 已验证
产品关联
DOI
高影响因子
ACS Applied Energy Materials
·
2019
·
IF 0
Meng Tian,Peiyi Wu
Silicon as an anode material of a Li-ion battery has attracted many researchers widespread attention for proper lithium intercalation potential and superhigh theoretical capacity. However, a Si-based anode possesses so poor a cycle life that it cannot be commercialized on account of the drastic volume expansion of silicon particles in the process of charge/discharge. Herein, we present a simple, green, and inexpensive way to improve cycle life of silicon-based electrodes by modifying active materials (more cheap and fragile Si submicroparticles (SiSMPs) than silicon nanoparticles) using tannic acid (TA) (a biocompatible nature plant polyphenol) and then interacting it with poly(acrylic acid) (PAA) binder. The tannic acid conformal coating can protect SiSMPs from side reactions with the electrolyte and can conjugate with the PAA binder and conductive materials, which keeps the electrode structure integrity during cycling. Furthermore, the TA coating makes the PAA binder form a 3D cross-linked network, which can enhance the binding strength compared with linear PAA chains, and the wet adhesion of the TA mussel-inspired coating can ensure good adhesion between SiSMPs and other components in electrolytes. Therefore, the combination between moderate amounts of TA coating and PAA can improve cycle performance and rate performance of low-cost submicrosized Si particle-based Li-ion battery anodes.
研究领域:
材料科学
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能源存储
·
绿色化学
✓ 已验证
产品关联
DOI
JOURNAL OF CHROMATOGRAPHY B-ANALYTICAL TECHNOLOGIES IN THE BIOMEDICAL AND LIFE SCIENCES
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2016
·
IF 2.687
Shuang Guo,Bai-Ling Qiu,Chen-Qi Zhu,Ya-Ya Gao Yang,Di Wu,Qi-Hui Liang,Nan-Yin Han
Gravitational field-flow fractionation (GrFFF) is a useful technique for separation and characterization for micrometer-sized particles. Elution behavior of micrometer-sized particles in GrFFF was researched in this study. Particles in GrFFF channel are subject to hydrodynamic lift forces (HLF), fluid inertial forces and gravity, which drive them to different velocities by carrier flow, resulting in a size-based separation. Effects of ionic strength, flow rate and viscosity as well as methanol were investigated using polystyrene latex beads as model particles. This study is devoted to experimental verification of the effect of every factor and their comprehensive function. All experiments were performed to show isolated influence of every variable factor. The orthogonal design test was used to evaluate various factors comprehensively. Results suggested that retention ratio of particles increases with increasing flow rate or the viscosity of carrier liquid by adjusting external forces acting on particles. In addition, retention ratio increases as ionic strength decreases because of decreased electrostatic repulsion between particles and channel accumulation wall. As far as methanol, there is no general trend due to the change of both density and viscosity. On the basis of orthogonal design test it was found that viscosity of carrier liquid plays a significant role in determining resolution of micrometer-sized particles in GrFFF.
研究领域:
分析化学
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胶体科学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
JOURNAL OF SOL-GEL SCIENCE AND TECHNOLOGY
·
2017
·Vol. 85
·期 1
·76-83
·
IF 1.575
Zhu Chunjie,Zhao Guangying,Dou Wenchao
Abstract In this paper, we aimed to develop a two-step approach for highly efficient synthesis of bright core-shell colored silica submicron particles (core-shell colored SiO 2 SMPs) by coupling organic reactive dyes onto silica submicron particle (SiO 2 SMPs). C.I. Reactive Blue 21 was selected as model dye to synthesize a core-shell blue silica submicron particle (core-shell blue SiO 2 SMPs). 3-[2-(2-aminoethylamino)ethylamino]propyl-trimethoxysilane (3APTMS) and C.I. Reactive Blue 21 were grafted simultaneously on the surface of particles in the aqueous solution to produce bright blue SiO 2 SMPs. The effect of the amount of 3APTMS and C.I. Reactive Blue 21 on preparation of blue SiO 2 SMPs was studied. To prevent dye on blue SiO 2 SMPs from leaking, core-shell blue SiO 2 SMPs were prepared in a pre-hydrolyzed Stöber system. Scanning Electronic Microscopy (SEM) and Dynamic Light Scattering (DLS) were used to character the SiO 2 SMPs, blue SiO 2 SMPs, and core-shell blue SiO 2 SMPs. The results indicate that the blue SiO 2 SMPs and core-shell blue SiO 2 SMPs synthesized under the optimal conditions with regular morphology and good dispersibility. Coupling efficiency of the C.I. Reactive Blue 21 was as high as 89.2% (the quality of dye coupled was about 70 mg/g SiO 2 ). In the same way, six other different colored SiO 2 SMPs were also prepared by introducing different color organic reactive dyes on SiO 2 SMPs. The bright monodispersed core-shell colored SiO 2 SMPs is promising to be used as sensitive and reproducible maker in immunoassay. Graphical abstract A one-step approach for the high efficiently coupling of reactive dyes onto SiO 2 SMPs in an aqueous solution to synthesize monodispersed colored SiO 2 SMPs was designed. The hydrolysis and condensation of 3APTMS and dye coupling were preceded at the same time. After modification and coloration, a silica protection layer was grown onto the colored SiO 2 SMPs to prevent the dye leakage and to make the colored SiO 2 SMPs be pure silica surface.
研究领域:
材料科学
·
生物学
✓ 已验证
产品关联
DOI
高影响因子
POWDER TECHNOLOGY
·
2022
·
IF 5.64
Guannan Yang,Haiqi Lai,Wei Lin,Jing Tong,Zhen Peng,Jun Cao,Jiye Luo,Yu Zhang,Chengqiang Cui
In this study, we explore the structure-property relationship of sintered metal nano/microparticles from the perspective of the agglomerate size effect. Through sintering experiments and mechanical tests of Cu particle pastes with different solvents, a linear correlation between the agglomerate size in the particle paste ( L a ) and the size of large-scale cavities in the sintered structure ( L c ) is revealed, and a negative correlation between the cavity size and the shear strength of the sintered structure is discovered. Based on these results, a quantitative model is proposed to predict the overall strength of the sintered structure ( τ f ). A relationship τ f = τ c /(1 + √(2 L cmax / d )) is established, which fits the experimental results very well. The model reveals that the relative agglomerate size ( L a / d ) or relative cavity size ( L c / d ) plays a more important role than the particle size ( d ) itself in terms of defining the final sintering properties of metal nano/microparticles.
研究领域:
材料科学
·
力学
✓ 已验证
产品关联
DOI
高影响因子
International Journal of Nanomedicine
·
2013
·
IF 3.463
Gaobo Long,Xiao-lan Yang,Yi Zhang,Jun Pu,Lin Liu,Hong-bo Liu,Yuan-li Li,Fei Liao
Purpose Magnetic submicron particles (MSPs) are pivotal biomaterials for magnetic separations in bioanalyses, but their preparation remains a technical challenge. In this report, a facile one-step coating approach to MSPs suitable for magnetic separations was investigated.Methods Polyethylene glycol) (PEG) was derived into PEG-bis-(maleic monoester) and maleic monoester-PEG-succinic monoester as the monomers. Magnetofluids were prepared via chemical co-precipitation and dispersion with the monomers. MSPs were prepared via one-step coating of magnetofluids in a water-in-oil microemulsion system of aerosol-OT and heptane by radical co-polymerization of such monomers.Results The resulting MSPs contained abundant carboxyl groups, exhibited negligible nonspecific adsorption of common substances and excellent suspension stability, appeared as irregular particles by electronic microscopy, and had submicron sizes of broad distribution by laser scattering. Saturation magnetizations and average particle sizes were affected mainly by the quantities of monomers used for coating magnetofluids, and steric hindrance around carboxyl groups was alleviated by the use of longer monomers of one polymerizable bond for coating. After optimizations, MSPs bearing saturation magnetizations over 46 emu/g, average sizes of 0.32 μm, and titrated carboxyl groups of about 0.21 mmol/g were obtained. After the activation of carboxyl groups on MSPs into N-hydroxysuccinimide ester, biotin was immobilized on MSPs and the resulting biotin-functionalized MSPs isolated the conjugate of streptavidin and alkaline phosphatase at about 2.1 mg/g MSPs; streptavidin was immobilized at about 10 mg/g MSPs and retained 81% ± 18% (n = 5) of the specific activity of the free form.Conclusion The facile approach effectively prepares MSPs for magnetic separations.
研究领域:
生物材料
·
生物分析
·
化学工程
✓ 已验证
DOI
PubMed
高影响因子
MOLECULES
·
2025
·Vol. 30
·期 11
·2429
·
IF 4.6
Wei Wang,Xiangyao Chen,Wen-Can Huang,Simiao Di,Jie Luo
This study presents a multilayer magnetic Janus sub-micrometric particle (MMJSP) as a nanoreactor for lipase catalysis. The core of the nanoparticle is constructed from a core-shell Fe3O4@SiO2framework, which serves as a precursor for the sequential amino and aldehyde modifications using 3-aminopropyltriethoxysilane and benzaldehyde. Following localized etching and subsequent modification with N,N-dimethyldodecylamine, a Janus nanoparticle with distinct hydrophilic and hydrophobic domains is synthesized. The resulting MMJSP demonstrates a stable attachment to the reaction interface and significantly enhances lipase performance, exhibiting 1.4-fold and 1.6-fold enhancements in activity after immobilization during 1 h hydrolysis and 24 h esterification reactions, respectively. Additionally, the storage stability of the immobilized lipase is improved by 100% over a period of 30 days. Reusability assessments reveal that the immobilized enzyme retains 80.7% activity after 10 cycles of esterification and 80.6% after 50 cycles of hydrolysis, with the magnetic properties allowing for rapid separation and recovery of the immobilized enzyme.
研究领域:
生物化学
·
材料科学
·
酶工程
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Journal of Central South University
·
2016
·Vol. 23
·期 11
·2784-2791
·
IF 0.562
Tian Qing-hua,Ning Wen-bo,Wang Wei-jia,Yuan Xiu-hong,Bai Zhi-ming
Large scaled uniform and size-controllable magnetic submicroparticles (MSPs) were synthesized via solvothermal method with ferric chloride as iron source and sodium acetate as trapping agent. The influence of Fe 3+ and NaAc contents on the size distribution of MSPs was investigated. The structural and morphological properties of the synthesized particles were studied by scanning electron microscopy (SEM), X-ray power diffraction (XRD) and vibrating sample magnetometer (VSM). The well-dispersed MSPs with size of 100-1000 nm were obtained by simply adjusting the contents of Fe 3+ and NaAc. In addition, the hemolysis and cytotoxicity of Fe 3 O 4 MSPs, and their ability to case arrest in cell life-cycles were studied. The results indicate that larger size could lead to lower hemolysis. From MTT(3-(4,5-dimethylthuazol-2-yl)-2,5-diphenyltetrazolium bromide) assay, the interactions between MSPs and adhesive mouse fibroblast cell line(L929) were probed. Larger size of Fe 3 O 4 MSPs demonstrates lower cell viability following an exposure to the cells.
研究领域:
材料科学
·
生物医学工程
✓ 已验证
产品关联
DOI
高影响因子
POWDER TECHNOLOGY
·
2022
·
IF 5.64
Jie Yin,Jun Zhang,Li Lv,Hui Zhong
Enhancing the growth performance of fine particles in supersaturated water vapor environment (SWVE) is an important means to further improve the removal efficiency of fine particles in coal-fired flue gas . In this paper, the growth performance of fine particles was strengthened by direct coupling magnetic field (MF) and heterogeneous condensation technology. The particle growth and measurement experimental platform was used to measure the effect of MF on the growth performance of heterogeneous condensation for high-concentration particles under different particle concentration and residence time. Our results show that the growth performance of insoluble submicron particles can be improved by direct coupling MF and heterogeneous condensation technology. After adding the MF with an intensity of 61.1 mT, the number of submicron particles decreases, and the number of particles with particle size greater than 2.1 μm increases in grown particles. At the same particle concentration and supersaturation , the arithmetic mean diameter of the grown particles in the SWVE with MF increases by 0.45%–2.32%, compared with that without magnetic field. Under the same residence time and supersaturation, the arithmetic mean diameter increases by 0.32%–6.89% for the grown particles in the SWVE with MF.
研究领域:
环境科学
·
物理学
✓ 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）