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
Thorium-234 and particle composition （organic matter, biogenic silica, carbonate and lithogenic component） were examined in the East China Sea （ECS） and the northern South China Sea （NSCS） in order to constrain ...Thorium-234 and particle composition （organic matter, biogenic silica, carbonate and lithogenic component） were examined in the East China Sea （ECS） and the northern South China Sea （NSCS） in order to constrain the particle types scavenging thorium isotopes. Good positive correlations between particulate organic matter （POM） or carbonate and thorium-234 in suspended particulate matter （SPM） indicates that POM and carbonate are efficient to scavenge thorium-234. No relationship between biogenic silica and thorium-234 suggests that geochemical behavior of thorium-234 may be not influenced by biogenic silica. A simple model was used to evaluate the affinity of thorium-234 to different particle components. The results show that POM is the most efficient scavenger for thorium-234 in the ECS and the NSCS, followed by carbonate. The authors＇ results lend support to the utility of thorium-234 as a proxy of POC and carbonate in the upper layer. However, the strong dependence of thorium scavenging on particle composition challenges thorium-230 as a constant flux proxy.展开更多
Novel bioactive injectable composites based on biopolymeric hydrogels reinforced with insulin-functionalized silica particles were synthesized.The insulin(INS)was immobilized on the surface of amine-modifed silica par...Novel bioactive injectable composites based on biopolymeric hydrogels reinforced with insulin-functionalized silica particles were synthesized.The insulin(INS)was immobilized on the surface of amine-modifed silica particles employing covalent attachment by EDC/NHS chemistry and via electrostatic interaction.The resulting formulations were examined for the morphology(SEM),chemical composition(FTIR,XPS)as well as protein content.To facilitate the injectability and support the bone regeneration,developed particles were dispersed in biopolymeric sol composed of collagen,chitosan and lysinemodifed hyaluronic acid and crosslinked with genipin.By means of rheological study,the sol-gel in situ transition of obtained systems was verifed.It was found in vitro study that MG-63 cells cultured on the developed composites exhibit signifcantly higher alkaline phosphatase(ALP)activity,compared to the pristine hydrogel.Furthermore,the biomineralization ability in the simulated body fluid(SBF)model was also demonstrated.Our fndings suggest that proposed herein novel hydrogel-based composites might be the promising formulation for regeneration of bone defects,especially as a less-cost effective support/alternative for BMP-2 systems.展开更多
In this paper, a facile synthesis of 100 nm commercial colloid silica coated with nano-ceria core-shell composite particles by the precipitation method using ammonium cerium nitrate and urea as a precipitator with pol...In this paper, a facile synthesis of 100 nm commercial colloid silica coated with nano-ceria core-shell composite particles by the precipitation method using ammonium cerium nitrate and urea as a precipitator with polyvinylpyrrolidone （PVP） as an assistant was briefly introduced. The results showed that the colloid silica was surrounded by nano-ceria uniformly forming the core-shell composite particles. The synthesis process was further discussed and optimized. It was found that the type and quantity of surfactant played a key role in the process. PVP connected the surface of colloid silica and that of the ceria precursor.展开更多
An access to an increase in the information storage capacity is to reduce memory units to a nano-scale. There fore, we used carboxylized phenyl-capped polyaniline tetramer (PCAT) as the functional component and silica...An access to an increase in the information storage capacity is to reduce memory units to a nano-scale. There fore, we used carboxylized phenyl-capped polyaniline tetramer (PCAT) as the functional component and silica as the carrier to prepare PCAT/silica composite nano-particles (= 60 nm) with a structure of core-shell. The functionalized particles were two-dimensionally arrayed on substrates such as silicon, glass and ITO glass at pH 3.SEM and AFM results proved the arraying regularity of these particles under any given conditions, and the electrostatic force microscopy showed their response to +3 V bias applied.展开更多
Nowadays, metallodielectric composite particles (especially spheres) have been the highlight to scientists due to their potential optical applications. In thi s paper, with wet chemistry method, we revised the Control...Nowadays, metallodielectric composite particles (especially spheres) have been the highlight to scientists due to their potential optical applications. In thi s paper, with wet chemistry method, we revised the Controlled-Double-Jet-Prec ipitation (CDJP) method and injected the silver salt and reducing agent into the silica-dispersed solution through two syringes. By changing the injected volum e and rate, we obtain silica/silver core/shell particles. TEM images show that t he silica surface was coated uniformly with silver nanoparticles and the samples were also uniform and low in polydispersity. Also XRD, EDX, DSC, UV-vis analys es were conducted to characterize thus-prepared samples.展开更多
基金Funded by Chinese National Natural Science Foundation (No.29674021) and Key Foundation (No. 59832090). and Open Foundation from State Key Lab. of Advanced Technology for Materials Synthesis and Processing.
文摘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.
基金The National Natural Science Foundation of China under contract Nos 40606022 and 90411016 the National Key Basic Research Special Foundation Program of China under contract No 2005CB422305
文摘Thorium-234 and particle composition （organic matter, biogenic silica, carbonate and lithogenic component） were examined in the East China Sea （ECS） and the northern South China Sea （NSCS） in order to constrain the particle types scavenging thorium isotopes. Good positive correlations between particulate organic matter （POM） or carbonate and thorium-234 in suspended particulate matter （SPM） indicates that POM and carbonate are efficient to scavenge thorium-234. No relationship between biogenic silica and thorium-234 suggests that geochemical behavior of thorium-234 may be not influenced by biogenic silica. A simple model was used to evaluate the affinity of thorium-234 to different particle components. The results show that POM is the most efficient scavenger for thorium-234 in the ECS and the NSCS, followed by carbonate. The authors＇ results lend support to the utility of thorium-234 as a proxy of POC and carbonate in the upper layer. However, the strong dependence of thorium scavenging on particle composition challenges thorium-230 as a constant flux proxy.
基金the financial support of National Science Centre,Poland,Grant 2016/21/D/ST5/01635。
文摘Novel bioactive injectable composites based on biopolymeric hydrogels reinforced with insulin-functionalized silica particles were synthesized.The insulin(INS)was immobilized on the surface of amine-modifed silica particles employing covalent attachment by EDC/NHS chemistry and via electrostatic interaction.The resulting formulations were examined for the morphology(SEM),chemical composition(FTIR,XPS)as well as protein content.To facilitate the injectability and support the bone regeneration,developed particles were dispersed in biopolymeric sol composed of collagen,chitosan and lysinemodifed hyaluronic acid and crosslinked with genipin.By means of rheological study,the sol-gel in situ transition of obtained systems was verifed.It was found in vitro study that MG-63 cells cultured on the developed composites exhibit signifcantly higher alkaline phosphatase(ALP)activity,compared to the pristine hydrogel.Furthermore,the biomineralization ability in the simulated body fluid(SBF)model was also demonstrated.Our fndings suggest that proposed herein novel hydrogel-based composites might be the promising formulation for regeneration of bone defects,especially as a less-cost effective support/alternative for BMP-2 systems.
基金supported by National Integrate Circuit Research Program of China (Nos.2011ZX02704-002,2009ZX02030-001)National Natural Science Foundation of China (No.51205387)Science and Technology Council of Shanghai (Nos.11nm0500300,10QB1403600)
文摘In this paper, a facile synthesis of 100 nm commercial colloid silica coated with nano-ceria core-shell composite particles by the precipitation method using ammonium cerium nitrate and urea as a precipitator with polyvinylpyrrolidone （PVP） as an assistant was briefly introduced. The results showed that the colloid silica was surrounded by nano-ceria uniformly forming the core-shell composite particles. The synthesis process was further discussed and optimized. It was found that the type and quantity of surfactant played a key role in the process. PVP connected the surface of colloid silica and that of the ceria precursor.
文摘An access to an increase in the information storage capacity is to reduce memory units to a nano-scale. There fore, we used carboxylized phenyl-capped polyaniline tetramer (PCAT) as the functional component and silica as the carrier to prepare PCAT/silica composite nano-particles (= 60 nm) with a structure of core-shell. The functionalized particles were two-dimensionally arrayed on substrates such as silicon, glass and ITO glass at pH 3.SEM and AFM results proved the arraying regularity of these particles under any given conditions, and the electrostatic force microscopy showed their response to +3 V bias applied.
文摘Nowadays, metallodielectric composite particles (especially spheres) have been the highlight to scientists due to their potential optical applications. In thi s paper, with wet chemistry method, we revised the Controlled-Double-Jet-Prec ipitation (CDJP) method and injected the silver salt and reducing agent into the silica-dispersed solution through two syringes. By changing the injected volum e and rate, we obtain silica/silver core/shell particles. TEM images show that t he silica surface was coated uniformly with silver nanoparticles and the samples were also uniform and low in polydispersity. Also XRD, EDX, DSC, UV-vis analys es were conducted to characterize thus-prepared samples.
