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Acoustic radiation force on a cylindrical composite particle with an elastic thin shell and an internal eccentric liquid column in a plane ultrasonic wave field
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作者 Rui-Qi Pan Zhi-Wei Du +2 位作者 Cheng-Hui Wang Jing Hu Run-Yang Mo 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第9期423-431,共9页
A model with three-layer structure is introduced to explore the acoustic radiation force(ARF)on composite particles with an elastic thin shell.Combing acoustic scattering of cylinder and the thin-shell theorem,the ARF... A model with three-layer structure is introduced to explore the acoustic radiation force(ARF)on composite particles with an elastic thin shell.Combing acoustic scattering of cylinder and the thin-shell theorem,the ARF expression was derived,and the longitudinal and transverse components of the force and axial torque for an eccentric liquid-filled composite particle was obtained.It was found that many factors,such as medium properties,acoustic parameters,eccentricity,and radius ratio of the inner liquid column,affect the acoustic scattering field of the particle,which in turn changes the forces and torque.The acoustic response varies with the particle structures,so the resonance peaks of the force function and torque shift with the eccentricity and radii ratio of particle.The acoustic response of the particle is enhanced and exhibits higher force values due to the presence of the elastic thin shell and the coupling effect with the eccentricity of the internal liquid column.The decrease of the inner liquid density may suppress the high-order resonance peaks,and internal fluid column has less effects on the change in force on composite particle at ka>3,while limited differences exist at ka<3.The axial torque on particles due to geometric asymmetry is closely related to ka and the eccentricity.The distribution of positive and negative force and torque along the axis ka exhibits that composite particle can be manipulated or separated by ultrasound.Our theoretical analysis can provide support for the acoustic manipulation,sorting,and targeting of inhomogeneous particles. 展开更多
关键词 acoustic radiation force acoustic scattering of cylinders elastic shell composite particles
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AgNi15 composite particles prepared by ultrasonic arc spray atomization method
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作者 谢建斌 温春明 +2 位作者 秦国义 许思勇 郭锦新 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2014年第11期3556-3561,共6页
Ultrasonic arc spray atomization (UASA) method was used to prepare high-melting-point, immiscible AgNi15 (mass fraction, %) composite particles. Sieving was used to determine the size distribution of the AgNi15 partic... Ultrasonic arc spray atomization (UASA) method was used to prepare high-melting-point, immiscible AgNi15 (mass fraction, %) composite particles. Sieving was used to determine the size distribution of the AgNi15 particles. The morphology, rapidly solidified structure and metastable solution expansion of the AgNi15 particles were analyzed by scanning electron microscopy (SEM), X-ray diffraction (XRD) and energy dispersive spectroscopy (EDS), respectively. The results show that the AgNi15 composite particles are spherical and well-dispersed, and the mass fractions of the particles with diameters <74μm and <55 μm are 99.5% and 98%, respectively. The rapidly solidified structure of the AgNi15 particles consists of spherical nickel-richβ(Ni)-phase particles dispersed throughout a silver-richα(Ag)-phase matrix andα(Ag)-phase nanoparticles dispersed throughout largerβ(Ni)-phase particles. The silver and nickel in the AgNi15 particles form a reciprocally extended metastable solution, and the solid solubility of nickel in the silver matrix at room temperature is in the range of 0.16%?0.36% (mole fraction). 展开更多
关键词 AgNi15 composite particle ultrasonic arc spray atomization rapidly solidified structure metastable solution extension
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Characterization of Calcined Kaolin/TiO_2 Composite Particle Material Prepared by Mechano-Chemical Method 被引量:3
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作者 王柏昆 丁浩 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 2010年第5期765-769,共5页
Calcined kaolin/TiO2 composite particle material (CK/TCPM) was prepared with TiO2 coating on the surfaces of calcined kaolin particles by the mechano-chemical method. X-ray diffraction (XRD) and scanning electron ... Calcined kaolin/TiO2 composite particle material (CK/TCPM) was prepared with TiO2 coating on the surfaces of calcined kaolin particles by the mechano-chemical method. X-ray diffraction (XRD) and scanning electron microscope (SEM) were used to investigate the microstructures and morphologies, respectively. The mechanism of the mechano-chemical reaction between calcined kaolin and TiO2 was studied by infrared spectra (IR). The results show that TiO2 coats evenly on the surfaces of calcined kaolin particles by Si-O-Ti and Al-O-Ti bonds on their interfaces. The hiding power and whiteness of CK/TCPM are 17.12 g/m^2 and 95.7%, respectively, presenting its similarity to TiO2 in pigment properties. 展开更多
关键词 mechano-chemical method calcined kaolin TIO2 composite particles material pigment properties
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Synthesis of nano-CaCO_3 composite particles and their application 被引量:2
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作者 Wei Wu Xueqin Zhang +1 位作者 Jianfeng Chen Shuling Shen 《Journal of University of Science and Technology Beijing》 EI CSCD 2008年第1期67-73,共7页
Nano-calcium carbonate composite particles were synthesized by the soapless emulsion polymerization technique of double monomers. The composite particles formation mechanism was investigated. The effects of composite ... Nano-calcium carbonate composite particles were synthesized by the soapless emulsion polymerization technique of double monomers. The composite particles formation mechanism was investigated. The effects of composite particles on the mechanical properties of nano-CaCO3-ABS (acrylonitrile-butadiene-styrene copolymer) composite material were studied. It was validated that the composite particles are made up of the nano-calcium carbonate cores and the shells of alternating copolymers of butyl acrylate (BA) and styrene (St). The shells are chemically grafted and physically wrapped on the surface of nano-calcium carbonate particles. When the composite particles were filled in ABS matrix, the CaCO3 particles are homogeneously dispersed in the composite material as nanoscales. The impact strength of the composite material is obviously enhanced after filling appropriate amounts of composite particles. It can be concluded that the soapless emulsion polymerization of double monomers is an effective method for nano-CaCO3 surface treatment. 2008 University of Science and Technology Beijing. All rights reserved. 展开更多
关键词 nano-calcium carbonate composite particles soapless emulsion polymerization composite material mechanical properties MECHANISM
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A simple method for purification of genomic DNA from whole blood using Fe_3O_4/Au composite particles as a carrier 被引量:1
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作者 Zhao Ming Zhang Xianqing +2 位作者 Wang Sen Chen Chao Cui Yali 《Journal of Medical Colleges of PLA(China)》 CAS 2009年第4期239-243,共5页
Objective: To establish a method of genomic DNA extraction from whole blood using Fe3O4/Au composite particles as a carrier. Methods: Two crucial conditions (sodium chloride concentration and amount of the magnetic... Objective: To establish a method of genomic DNA extraction from whole blood using Fe3O4/Au composite particles as a carrier. Methods: Two crucial conditions (sodium chloride concentration and amount of the magnetic particles) were optimized and 8 different human whole blood samples were used to purify genomic DNA under the optimal condition. Then agarose gel electrophoresis and polymerase cbain reaction (PCR) were performed. Results: The optimal binding condition was 1.5 mol/L NaC1/10% PEG, and the optimal amount of Fe3O4/Au composite particles was 600μg. The yields of the genomic DNA from 100μl of different whole blood samples were 2-5 μg, and the ratio of A260/A280 was in the range of 1.70-1.90. The size of genomic DNA was about 23 kb and the PCR was valid. Conclusion: The purification system using Fe3O4/Au composite microparticles has advantages in high yield, high purity, ease of operating, time saving and avoiding centrifugation. The purified sample was found to function satisfactorily in PCR amplification. 展开更多
关键词 Fe3O4/Au composite particles Genomic DNA PURIFICATION Whole blood
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HYBRID AND CHARACTERISTIC OF POLYANILINEBARIUM TITANATE NANOCOMPOSITE PARTICLES
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作者 龚荣洲 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 2000年第3期62-66,共5页
Polyaniline-barium titanate (PAn-Ba-TiO3) ultrafine composite particles were prepared by the oxidative polymerization of aniline with H2O2 while barium titanate nanoparticles were synthesized with a sol-gel method. Th... Polyaniline-barium titanate (PAn-Ba-TiO3) ultrafine composite particles were prepared by the oxidative polymerization of aniline with H2O2 while barium titanate nanoparticles were synthesized with a sol-gel method. The infrared spectrogram shows that the polymerization of PAn in the hybrid process of PAn-BaTiO3 is similar with the polymeric process of pure aniline, and there is interaction of PAn and BaTiO3 in the PAn-Ba-TiO3. SEM and TEM results show that the average diameter of the composite particles is 1.50μm and the diameters of BaTiO3 nanoparticles are 5 - 15 nm in the composite particle. The electrical conductivity of the ultrafine com-posite particles is transformable from 10°to 10-11S/cm by equilibrium doping or dedoping method using various concentration of HCl or NaOH solutions. 展开更多
关键词 ultrafine composite particles barium titanate POLYANILINE composite in situ
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Sol-Gel Preparation of Graphite/TiO_2 Composite Particles and Their Electrorheological Effect
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作者 Ling ZHENG and Yinong LIState Key Laboratory of Mechanical Transmission, Chongqing University, Chongqing 400044, ChinaAssoc. Prof., Ph.D., 《Journal of Materials Science & Technology》 SCIE EI CAS CSCD 2005年第1期83-86,共4页
Graphite/TiO2 composite particles were obtained by sol-gel technique in this paper. The structure and characteristic of the composite particles are analyzed by XRD, SEM and TG-DTA. The electrorheological properties of... Graphite/TiO2 composite particles were obtained by sol-gel technique in this paper. The structure and characteristic of the composite particles are analyzed by XRD, SEM and TG-DTA. The electrorheological properties of the ER fluid containing the particles were measured by a Couette-type rheometer under shear rates of 1-136 s-1 and AC electric fields of 0-3 kV/mm. The experimental results show that the leaking current density of the ER fluid is higher than that of pure titanium dioxide particles dispersed in damping oil. The shear yield stress of the ER fluid increases with increasing electric field and exhibits a typical Bingham flow behavior. The suspension demonstrates an excellent ER performance (τ/τo=1200) compared with conventional ER fluids (τ/τ0 ≤500). The sedimentation of the ER fluid is improved obviously due to the coating effect of the particles. 展开更多
关键词 Electrorheological fluid composite particle GRAPHITE TIO2 SOL-GEL
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Rheological properties of magnetorheological fluid prepared by gelatincarbonyl iron composite particles
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作者 潘华锦 黄红军 +2 位作者 张灵振 齐建英 曹少坤 《Journal of Central South University of Technology》 EI 2005年第4期411-415,共5页
Gelatincarbonyl iron composite particle was prepared by micro emulsion method. The analysis of scanning electron microscope(SEM) shows that the ultrafine particles are spheroids coated by gelatin, and the average size... Gelatincarbonyl iron composite particle was prepared by micro emulsion method. The analysis of scanning electron microscope(SEM) shows that the ultrafine particles are spheroids coated by gelatin, and the average sizes of particles are 310μm. The specific saturation magnetization σ_s is 130.9A·m2/kg, coercivity H_c is 0.823A/m, and residual magnetism r is 4.98Am2/kg for the composite particles. It is shown that the particles possess properties of soft magnetic. The yield stress of magnetorheological fluid(MRF) with composite particle reaches 70kPa at 0.5T magnetic induction. Magnetorheological effects are superior in lower magnetic field intensity and the subsidence stability of the MRF is excellent compared with pure carbonyl iron powder. 展开更多
关键词 micro emulsion composite particle gelatin carbonyl iron yield stress
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<i>H</i>, <i>W</i>, <i>Z</i>Bosons, Dark Matter: Composite Particles?
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作者 Raymond Fèvre 《Journal of High Energy Physics, Gravitation and Cosmology》 2021年第2期687-697,共11页
The present article develops a model initially published in ref. [1]. It is a quasi-classical quantum model of composite particles with ultra-relativistic (UR) constituents (leptons and quarks). The model is used to c... The present article develops a model initially published in ref. [1]. It is a quasi-classical quantum model of composite particles with ultra-relativistic (UR) constituents (leptons and quarks). The model is used to calculate the mass energy of three composite particles: a UR tauonium, a UR bottomonium and a UR leptoquarkonium. The result is that these three hypothetic particles have masses close to 125 GeV: the Higgs boson mass energy. These results are recalled in the present article. Then the model is extended to calculate the mass energy of <i>pi</i>-mesons, <i>W</i> and <i>Z</i> bosons. Finally, the model provides a hypothesis on dark matter. 展开更多
关键词 Higgs Boson W and Z bosons Dark Matter Pi-Mesons composite particle
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Observation of interface of two kinds of bi-metal composite parts prepared by thixo-forging 被引量:4
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作者 杨昭 周丽 董建雄 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2010年第9期1579-1584,共6页
Two kinds of bi-metal composite parts (Sn-15%Pb and Pb-22%Sn bi-metal system, and Al-7%Si and SiCp/6061 MMC bi-metal system) were prepared by the strain-induced melt activated thixo-forging. The interfaces of the bi... Two kinds of bi-metal composite parts (Sn-15%Pb and Pb-22%Sn bi-metal system, and Al-7%Si and SiCp/6061 MMC bi-metal system) were prepared by the strain-induced melt activated thixo-forging. The interfaces of the bi-metal composites were observed by OM and SEM. The observations show that the semisolid metals keep independence during thixo-forging. The solid phases in the semisolid slurries maintain their original morphologies after thixo-forging. The liquid phases near the interface mix together and form a thin layer. The interfaces are bonded firmly with the metallurgical bonding. No oxide layers are found at the interfaces. Strengths of the interfaces were investigated by the micro-hardness test. The experimental results show that the composite interfaces have high strength. However, the agglomerated enhancing particles cause fine defect on the interface of the Al-7%Si and SiCr/6061 MMC bi-metal composite. 展开更多
关键词 semisolid metal processing bi-metal composite thixo-forming die-forging metal matrix composite
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Preparation and Tribological Properties of Lanthanum-doped Muscovite Composite Particles as Lubricant Additives in Lithium Grease 被引量:4
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作者 Du Pengfei Chen Guoxu +4 位作者 Song Shiyuan Zhao Litao Wu Jiang Cheng Peng Yang Xiao 《China Petroleum Processing & Petrochemical Technology》 SCIE CAS 2016年第2期100-107,共8页
Lanthanum-doped muscovite(MC) composite particles(hereinafter abbreviated as La-MC) were prepared by the mechanical solid-state-chemistry-reaction method, followed by surface modification with oleic acid. The microstr... Lanthanum-doped muscovite(MC) composite particles(hereinafter abbreviated as La-MC) were prepared by the mechanical solid-state-chemistry-reaction method, followed by surface modification with oleic acid. The microstructure of materials was characterized by SEM, XRD, EDS and FTIR. Furthermore, the friction-reduction and anti-wear properties of MC and La-MC as lubricant additives in lithium grease were evaluated using a four-ball friction and wear tester. The results showed that La(OH)_3 nanoparticles were coated on the surface of muscovite. Both MC and La-MC can effectively improve the friction-reduction and anti-wear properties of lithium grease and La-MC presents better tribological properties than MC. The excellent tribological properties of La-MC can be attributed to the formation of the adsorbed La-MC film and the chemical reaction film mainly composed of Fe_2O_3 and SiO_2 on the worn surface, as well as the catalysis of lanthanum element during the friction process. 展开更多
关键词 MUSCOVITE composite particles LUBRICANT ADDITIVES friction-reduction and ANTI-WEAR mechanism
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Comparison of wear behavior of ABS and Nylon6-Fe powder composite parts prepared with fused deposition modelling 被引量:2
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作者 Harish Kumar Garg Rupinder Singh 《Journal of Central South University》 SCIE EI CAS CSCD 2015年第10期3705-3711,共7页
Fused deposition modeling(FDM) is one of the latest rapid prototyping techniques in which parts can be manufactured at a fast pace and are manufactured with a high accuracy. This research work is carried out to study ... Fused deposition modeling(FDM) is one of the latest rapid prototyping techniques in which parts can be manufactured at a fast pace and are manufactured with a high accuracy. This research work is carried out to study the friction and wear behavior of parts made of newly developed Nylon6-Fe composite material by FDM. This work also involves the comparison of the friction and wear characteristics of the Nylon6-Fe composite with the existing acrylonitrile butadiene styrene(ABS) filament of the FDM machine. This Is carried out on the pin on disk setup by varying the load(5, 10, 15 and 20 N) and speed(200 and 300 r/min). It is concluded that the newly developed composite is highly wear resistant and can be used in industrial applications where wear resistance is of paramount importance. Morphology of the surface in contact with the Nylon6-Fe composite and ABS is also carried out. 展开更多
关键词 composite material fused deposition modeling(FDM) parts TRIBOLOGY pin on disc iron(Fe) Nylon 6 acrylonitrile butadiene styrene(ABS)
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Formation mechanisms of sub-micron pharmaceutical composite particles derived from far-and near-field Raman microscopy 被引量:2
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作者 Jakob Hübner Jean-Baptiste Coty +1 位作者 Yan Busby Denis Spitzer 《Journal of Pharmaceutical Analysis》 SCIE CAS CSCD 2021年第4期480-489,共10页
Surface enhanced Raman spectroscopy(SERS) and confocal Raman microscopy are applied to investigate the structure and the molecular arrangement of sub-micron furosemide and polyvinylpyrrolidone(furosemide/PVP) particle... Surface enhanced Raman spectroscopy(SERS) and confocal Raman microscopy are applied to investigate the structure and the molecular arrangement of sub-micron furosemide and polyvinylpyrrolidone(furosemide/PVP) particles produced by spray flash evaporation(SFE). Morphology, size and crystallinity of furosemide/PVP particles are analyzed by scanning electron microscopy(SEM) and X-ray powder diffraction(XRPD). Far-field Raman spectra and confocal far-field Raman maps of furosemide/PVP particles are interpreted based on the far-field Raman spectra of pure furosemide and PVP precursors.Confocal far-field Raman microscopy shows that furosemide/PVP particles feature an intermixture of furosemide and PVP molecules at the sub-micron scale. SERS and surface-enhanced confocal Raman microscopy(SECo RM) are performed on furosemide, PVP and furosemide/PVP composite particles sputtered with silver(40 nm). SERS and SECo RM maps reveal that furosemide/PVP particle surfaces mainly consist of PVP molecules. The combination of surface and bulk sensitive analyses reveal that furosemide/PVP sub-micron particles are formed by the agglomeration of primary furosemide nanocrystals embedded in a thin PVP matrix. Interestingly, both far-field Raman microscopy and SECo RM provide molecular information on a statistically-relevant amount of sub-micron particles in a single microscopic map;this combination is thus an effective and time-saving tool for investigating organic sub-micron composites. 展开更多
关键词 SERS Confocal Raman microscopy Surface characterization Sub-micron particles Pharmaceutic composites
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Idealization Second Quantization of Composite Particles
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作者 ZHOU Duan-Lu YU Si-Xia SUN Chang-Pu 《Communications in Theoretical Physics》 SCIE CAS CSCD 2001年第11期525-530,共6页
A practical method is developed to deal with the second quantization of the many-body system containing the composite particles.In our treatment,the modes associated with composite particles are regarded approximately... A practical method is developed to deal with the second quantization of the many-body system containing the composite particles.In our treatment,the modes associated with composite particles are regarded approximately as independent ones compared with those of unbound particles.The field operators of the composite particles thus arise naturally in the second quantization Hamiltonian.To be emphasized,the second quantization Hamiltonian has the regular structures which correspond clearly to different physical processes. 展开更多
关键词 SECOND quantization composite partICLES
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C-V Characterization of α-Fe_2O_3/Block-Copolymer Composite Particulate Films
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作者 QIAN Xin-ming AI Xin +4 位作者 TANG Jun WANG Da-yang ZHANG Xin-tong SONG Qing BAI Yu-bai LI Tie-jin and TANG Xin-yi (Department of Chemistry, Jilin University, Changchun 130023, P. R. China) 《Chemical Research in Chinese Universities》 SCIE CAS CSCD 2000年第1期57-60,共4页
α-Fe_2O_3 nanocrystal was encapsulated by a block-copolymer, hydroxylated poly (styrene-b- butadiene-styrene) (HO-SBS) to fabricate composite microspheres with α-Fe_2O_3 cores and HOSBS shell. Its film fabricated o... α-Fe_2O_3 nanocrystal was encapsulated by a block-copolymer, hydroxylated poly (styrene-b- butadiene-styrene) (HO-SBS) to fabricate composite microspheres with α-Fe_2O_3 cores and HOSBS shell. Its film fabricated on n-Si wafer acts as the insulator layer in the metal-insulator- semiconductor(MIS) structure. The capacitance-voltage (C-V) properties were measured to characterize the composite particulate films. 展开更多
关键词 α-Fe_2O_3 nanocrystal/block-copolymer composite Metal-insulator-semiconductor structure CAPACITANCE-VOLTAGE
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Preparation of Composite Particles by Forming Pickering Emulsion Followed by Drying-In-Liquid and Effect of Stepwise Addition of Solid Powder on Structure of Composite Particles
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作者 Yasushi Akutsu Yoshinari Taguchi Masato Tanaka 《Materials Sciences and Applications》 2013年第12期786-793,共8页
It was tried to prepare composite particles made of polymer and two kinds of solid powders by forming Pickeringemulsion followed by the drying-in-liquid method and to investigate how the stepwise addition of solid pow... It was tried to prepare composite particles made of polymer and two kinds of solid powders by forming Pickeringemulsion followed by the drying-in-liquid method and to investigate how the stepwise addition of solid powders affected the contained ratio and adhesion ratio of solid powders and the structure of composite particles. Limonene oil dissolving expanded polystyrene and ethylene glycol were adopted as the dispersed phase and the continuous phase, respectively. Magnetite and titanium dioxide were used as solid powders. Magnetite was added before or after formation of the (O/W) dispersion. Titanium dioxide was added at the various elapsed times from addition of magnetite. Titanium dioxide adhered only on the surface of composite particles irrespective of addition time. At the earlier addition of both solid powders, the surface-covering type composite particles were prepared. At the latter addition of titanium dioxide, a part of magnetite adhered on the surface and the remainder was dispersed into composite particle. 展开更多
关键词 composite particles PICKERING EMULSION Drying-In-Liquid Method LIQUID-LIQUID Dispersion MAGNETITE Titanium Dioxide
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Preparation of Polymer Composite Particles by Phase Separation Followed by Suspension Polymerization
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作者 Yoshinari Taguchi Takanori Suzuki +2 位作者 Natsukaze Saito Hiroshi Yokoyama Masato Tanaka 《Open Journal of Composite Materials》 2017年第1期1-13,共13页
The novel method for preparing the polymer composite particles has been developed. It was tried to prepare polymer composite particles composed of polystyrene and carbon black with the phase separation method followed... The novel method for preparing the polymer composite particles has been developed. It was tried to prepare polymer composite particles composed of polystyrene and carbon black with the phase separation method followed by suspension polymerization. In order to prepare the polymer composite particles with the more uniform diameter, the styrene monomer droplets containing carbon black were formed with phase separation emulsification in which ethyl alcohol and water were used as the good solvent and the poor solvent for styrene monomer, respectively. In the experiment, the surfactant species and their concentrations, the pouring velocity of water and the weight ratio of carbon black to styrene monomer were mainly changed. Water was poured at the given pouring velocity into ethyl alcohol in which styrene monomer and an initiator were dissolved and carbon black was dispersed beforehand. The spherical polymer composite particles containing carbon black were prepared with Tween 20 and Tween 80 of nonionic surfactants and the irregular polymer composite particles were prepared with PVA, SDS and Kotamine. The diameters of polymer composite particles increased with the pouring velocity of water and with the weight ratio of carbon black to styrene monomer. 展开更多
关键词 Polymer composite partICLES Phase Separation Suspension POLYMERIZATION POLYSTYRENE BEADS Carbon Black AMPHIPHILIC Solvent
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Preparation of Composite Particles Made of Biodegradable Polymer and a Few Additives with Phase Separation Followed by Drying-in-Liquid
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作者 Mitsuru Kutsuwada Yoshinari Taguchi Masato Tanaka 《Journal of Encapsulation and Adsorption Sciences》 2015年第1期11-20,共10页
It was tried to prepare the biodegradable composite particles by the phase separation method followed by the drying-in-liquid method. The composite particles were made of poly-ε-caprolac-tone, quaternary ammonium, ca... It was tried to prepare the biodegradable composite particles by the phase separation method followed by the drying-in-liquid method. The composite particles were made of poly-ε-caprolac-tone, quaternary ammonium, carbon black and wax. In the experiment, acetone and water were selected as a good solvent and a poor solvent for poly-ε-caprolactone, quaternary ammonium and wax, respectively. The composite particles were prepared by changing the surfactant species and their concentration, the feeding velocity of water and the weight ratio of poly-ε-caprolactone with larger molecular weight to one with smaller molecular weight. The composite particles with the inner structure in which carbon black, quaternary ammonium and wax were coated well with poly-ε-caprolactone could be prepared by the preparation method presented in this study. The structure and the mean diameter of composite particles were strongly affected by the feeding velocity of water. The higher the feeding velocity of water, the larger the mean diameter of composite particles. The mean diameter was drastically decreased with the surfactant concentration and increased with the added amount of poly-ε-caprolactant with larger molecular weight. 展开更多
关键词 BIODEGRADABLE composite particles Phase Separation Drying-in-Liquid Poly-ε-Caprolactone MICROENCAPSULATION
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Fabrication and Characterization of Chitosan Based Injectable Thermosensitive Hydrogels Containing Silica/Calcium Phosphate Nanocomposite Particles
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作者 Seyed Mohsen Latifi Christina Tang Henry J. Donahue 《Journal of Biomaterials and Nanobiotechnology》 2021年第3期34-48,共15页
In this study, the effect of silica/calcium phosphate (SiCaP) nanocomposite particles on the properties of a novel chitosan-based thermosensitive hydrogel system was examined. SiCaP nanocomposite powder was fabricated... In this study, the effect of silica/calcium phosphate (SiCaP) nanocomposite particles on the properties of a novel chitosan-based thermosensitive hydrogel system was examined. SiCaP nanocomposite powder was fabricated using a sol-gel method and then used to fabricate nanocomposite hydrogels (Ch- <em>β</em>/7.5SiCaP and Ch-<em>β</em>/15SiCaP) including chitosan and <em>β</em>-glycerophosphate (Ch-<em>β</em>) as a matrix. Results revealed that compared to the Ch-<em>β </em>hydrogel without SiCaP, the presence of SiCaP particles in nanocomposite hydrogels maintained pH stability during the sol-gel transition, accelerated the gelation and improved the stiffness of nanocomposite hydrogels. Gelation time at 37℃ was reduced approximately 75% and stiffness was increased approximately 115%. Both of these changes are attributed to chemical and physical interactions of the SiCaP bioactive particles with chitosan. Furthermore, compared to the Ch-<em>β</em> hydrogel, the presence of SiCaP in the Ch-<em>β</em>/7.5SiCaP nanocomposite hydrogel did not affect biocompatibility negatively, but improved osteoblastic cell differentiation. Our studies suggest that these nanocomposite hydrogels may offer an innovative approach to bone regeneration strategies. 展开更多
关键词 THERMOSENSITIVITY composite Hydrogel Bioactive particles RHEOLOGY BIOCOMPATIBILITY
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The Angular Distribution of Light Composite Particle Projectile in Preequilibrium Reactions
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作者 Shen Qingbiao(China Institute of Atomic Energy,P.O.Box 275,Beijing 102413) 《Chinese journal of nuclear physics》 1994年第2期160-169,共10页
Formulations of double differential cross sections of light composite particleconsidering (1,m) and (2,m) pickup type reactions simultaneously for semi-classicalmulti-step compound and direct processes are presented.T... Formulations of double differential cross sections of light composite particleconsidering (1,m) and (2,m) pickup type reactions simultaneously for semi-classicalmulti-step compound and direct processes are presented.The calculated results of crosssections,spectra,and double differential cross sections indicate that generally the con-tributions of the (2,m) pickup type reactions are about 15%-25% when the incident en-ergies are below 50 MeV but can become dominant when the incident energies areabove 50 MeV in some region of the outgoing energies and angles.The forward tenden-cy of the calculated angular distributions by (2,m) configuration is weaker than those by(1,m) configuration.For the reactions of outgoing composite particle with higher inci-dent energy,the multi-step direct process must be considered. 展开更多
关键词 Preequilibrium composite partICLE Double DIFFERENTIAL CROSS SECTION
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