A hollow glass microsphere(HGM)/TiO2 composite hollow sphere was successfully prepared via a simple precipitation method.The TiO2 coating layers grew on the surface of the HGMs that range from 20 to 50μm in diameter ...A hollow glass microsphere(HGM)/TiO2 composite hollow sphere was successfully prepared via a simple precipitation method.The TiO2 coating layers grew on the surface of the HGMs that range from 20 to 50μm in diameter as nanoparticles with the formation of the SiO Ti bonds.The growth mechanism accounting for the formation of the TiO2 nanolayers was proposed.The morphology,composition,thermal insulation properties,and visible-near infrared(VIS-NIR)refl ectance of the HGMs/TiO2 composite hollow spheres were characterized.The VIS-NIR reflectance of the HGMs/TiO2 composite hollow spheres increased by more than 30%compared to raw HGMs.The thermal conductivity of the particles is 0.058 W/(m K).The result indicates that the VIS-NIR reflectance of the composite hollow spheres is strongly influenced by the coating of TiO2.The composite hollow spheres were used as the main functional filler to prepare the organic-inorganic composite coatings.The glass substrates coated by the organic-inorganic coatings had lower thermal conductivity and higher near infrared reflectivity.Therefore,the HGMs/TiO2 composite hollow spheres can reflect most of the solar energy and effectively keep out the heat as a thermal insulation coating for energy-saving constructions.展开更多
TiO2-coated SnO2 （TCS） hollow spheres, which are new anode materials for lithium ion （Li-ion） batteries, were prepared and characterized with X-ray diffraction （XRD）, scanning electron microscopy （SEM）, transm...TiO2-coated SnO2 （TCS） hollow spheres, which are new anode materials for lithium ion （Li-ion） batteries, were prepared and characterized with X-ray diffraction （XRD）, scanning electron microscopy （SEM）, transmission electron microscopy （TEM）, cyclic voltammetry （CV）, and galvanostatic charge/discharge tests. The results obtained from XRD, SEM, and TEM show that TiO2 can be uniforrrdy coated on the surface of SnO2 hollow spheres with the assistance of anionic surfactant. The cyclic voltammograms indicate that both TiO2 and SnO2 exhibit the activity for Li-ion storage. The charge/discharge tests show that the prepared TCS hollow spheres have a higher reversible coulomb efficiency and a better cycling stability than the uncoated SnO2 hollow spheres.展开更多
The anti-bacterial adhesion properties of TiO2-coated polymethyl methacrylate （PMMA） surfaces are investigated systematically. In detail, the adhesion of S. aureus （gram positive） and E. coli （gram negative） to ...The anti-bacterial adhesion properties of TiO2-coated polymethyl methacrylate （PMMA） surfaces are investigated systematically. In detail, the adhesion of S. aureus （gram positive） and E. coli （gram negative） to TiO2-coated and uncoated PMMA surfaces are performed by the plate counting method. Afterwards, the adhesion free energy of bacteria on both supporting materials is quantified using the thermodynamic approach of Lifshitz van der Waals and acid/base interactions. The superior anti-adhesion capability of TiO2-coated PMMA is demonstrated when compared to native PMMA, both experimentally and theoretically.展开更多
As an important green manufacturing process,dry grinding has problems such as high grinding temperature and insufficient cooling capacity.Aiming at the problems of sticking and burns in dry grinding of titanium alloys...As an important green manufacturing process,dry grinding has problems such as high grinding temperature and insufficient cooling capacity.Aiming at the problems of sticking and burns in dry grinding of titanium alloys,grinding performance evaluation of molybdenum disulfide(MoS_(2))solid lubricant coated brazed cubic boron carbide(CBN)grinding wheel(MoS_(2)-coated CBN wheel)in dry grinding titanium alloys was carried out.The lubrication mechanism of MoS_(2)in the grinding process is analyzed,and the MoS_(2)-coated CBN wheel is prepared.The results show that the MoS_(2)solid lubricant can form a lubricating film on the ground surface and reduce the friction coefficient and grinding force.Within the experimental parameters,normal grinding force decreased by 42.5%,and tangential grinding force decreased by 28.1%.MoS_(2)lubricant can effectively improve the heat dissipation effect of titanium alloy grinding arc area.Compared with common CBN grinding wheel,MoS_(2)-coated CBN wheel has lower grinding temperature.When the grinding depth reaches 20μm,the grinding temperature decreased by 30.5%.The wear of CBN grains of grinding wheel were analyzed by mathematical statistical method.MoS_(2)lubricating coating can essentially decrease the wear of grains,reduce the adhesion of titanium alloy chip,prolong the service life of grinding wheel,and help to enhance the surface quality of workpiece.This research provides high-quality and efficient technical support for titanium alloy grinding.展开更多
The simulation by the Monte Carlo method executed by the software PyPENELOPE proved effective to specify the particle propagation characteristics by calculating the absorption fractions, backscattering and transmissio...The simulation by the Monte Carlo method executed by the software PyPENELOPE proved effective to specify the particle propagation characteristics by calculating the absorption fractions, backscattering and transmission of electrons and secondary photons under the incidence of 0.5 to 20 KeV range of primary electrons. More than 99.9% of the primary electrons were transmitted in the 125 nm thick MgO/TiO<sub>2</sub> material at 20 KeV. This occurred because several interactions took place in the transmitted primary irradiation such as characteristic, fluorescence, and bremsstrahlung produced when of the occupation of the KL3, KL2, KM3, and KM2 shell and sub-shell of titanium and magnesium which are the elements with a high atomic number in the material. The transmission particle characteristic of this material is therefore an indicator capable of improving the electrical performance and properties of the sensor.展开更多
This study focused on the development and characterization of TiO<sub>2</sub>-PES composite fibers with varying TiO<sub>2</sub> loading amounts using a phase inversion process. The resulting co...This study focused on the development and characterization of TiO<sub>2</sub>-PES composite fibers with varying TiO<sub>2</sub> loading amounts using a phase inversion process. The resulting composite fibers exhibited a sponge-like structure with embedded TiO<sub>2</sub> nanoparticles within a polymer matrix. Their photocatalytic performance for ammonia removal from aqueous solutions under UV-A light exposure was thoroughly investigated. The findings revealed that PeTi8 composite fibers displayed superior adsorption capacity compared to other samples. Moreover, the study explored the impact of pH, light intensity, and catalyst dosage on the photocatalytic degradation of ammonia. Adsorption equilibrium isotherms closely followed the Langmuir model, with the results indicating a correlation between qm values of 2.49 mg/g and the porous structure of the adsorbents. The research underscored the efficacy of TiO<sub>2</sub> composite fibers in the photocatalytic removal of aqueous under UV-A light. Notably, increasing the distance between the photocatalyst and the light source resulted in de-creased hydroxyl radical concentration, influencing photocatalytic efficiency. These findings contribute to our understanding of TiO<sub>2</sub> composite fibers as promising photocatalysts for ammonia removal in water treatment applications.展开更多
The photocatalytic degradation of the synthetic textile dye Reactive Yellow 145 (RY 145) in aqueous solution, using TiO2 coated non-woven fibers as photocatalyst, under UV-lamp irradiation, was studied. The effects of...The photocatalytic degradation of the synthetic textile dye Reactive Yellow 145 (RY 145) in aqueous solution, using TiO2 coated non-woven fibers as photocatalyst, under UV-lamp irradiation, was studied. The effects of the operational parameters such as initial dye concentration, pH, addition of oxidant hydrogen peroxide and addition of ethanol on the reaction rate were investigated. The effect of some inorganic ions such as and , commonly present in real effluents, on the photodegradation of RY 145 was also examined. The experimental results showed that the photocatalytic degradation rate was favoured by a high concentration of solution in respect to Langmuir-Hinshelwood model. The maximum rate of complete decolorization of RY 145 was observed in the acidic medium at pH 3. The presence of and anions led to an increase of the effectiveness of the photocatalytic degradation. However, the presence of and anions decreased differently the photodegradation reaction rate. TiO2/UV process was proved to be capable of the complete degradation of the RY 145.展开更多
Several lithium-ion batteries of 18650-type were assembled with pristine or Al2O3-coated LiNi0.4Co0.2Mn0.4O2（NCM） as cathode material and mesocarbon microbeads（MCMB） as anode material.The cycling performance of th...Several lithium-ion batteries of 18650-type were assembled with pristine or Al2O3-coated LiNi0.4Co0.2Mn0.4O2（NCM） as cathode material and mesocarbon microbeads（MCMB） as anode material.The cycling performance of the batteries was examined under 25 °C at a 2C rate within a potential range of 2.75―4.20 V.The changes of the crystal structure,the lattice parameter,the mean crystallite size,and the mean micro-strain of pristine NCM and Al2O3-coated NCM during the charge-discharge cycling were determined by X-ray diffraction（XRD）.The results indicate that the bulk structure of Al2O3-coated NCM is more stable than that of pristine NCM,which leads to the better cycling performance of Al2O3-coated NCM compared to that of pristine NCM.展开更多
Growth of single-crystal Sn O_2 nanowires using a fluorine-doped Sn O_2(FTO) thin film as both the source and substrate is demonstrated for the first time at relatively low temperature(580 °C) which preserves the...Growth of single-crystal Sn O_2 nanowires using a fluorine-doped Sn O_2(FTO) thin film as both the source and substrate is demonstrated for the first time at relatively low temperature(580 °C) which preserves the integrity of the underlying glass support and improves scalability to devices. Furthermore, a microwave hydrothermal process is shown to grow Ti O_2 nanorods on these nanowires to create a hierarchical nanoheterostructure that will lead to efficient photogenerated charge carrier separation and rapid transport of electrons to the substrate. This process simplifies nanowire growth by using commercially available and widely used FTO substrates without the need for an additional upstream Sn source and can be used as a high surface area host structure to many other hierarchical structures.展开更多
文摘A hollow glass microsphere(HGM)/TiO2 composite hollow sphere was successfully prepared via a simple precipitation method.The TiO2 coating layers grew on the surface of the HGMs that range from 20 to 50μm in diameter as nanoparticles with the formation of the SiO Ti bonds.The growth mechanism accounting for the formation of the TiO2 nanolayers was proposed.The morphology,composition,thermal insulation properties,and visible-near infrared(VIS-NIR)refl ectance of the HGMs/TiO2 composite hollow spheres were characterized.The VIS-NIR reflectance of the HGMs/TiO2 composite hollow spheres increased by more than 30%compared to raw HGMs.The thermal conductivity of the particles is 0.058 W/(m K).The result indicates that the VIS-NIR reflectance of the composite hollow spheres is strongly influenced by the coating of TiO2.The composite hollow spheres were used as the main functional filler to prepare the organic-inorganic composite coatings.The glass substrates coated by the organic-inorganic coatings had lower thermal conductivity and higher near infrared reflectivity.Therefore,the HGMs/TiO2 composite hollow spheres can reflect most of the solar energy and effectively keep out the heat as a thermal insulation coating for energy-saving constructions.
基金financially supported by the National Natural Science Foundation of China (No.20873046)the Specialized Research Fund for the Doctoral Program of HigherEducation (No.200805740004)Natural Science Foundation of Guangdong Province (No.10351063101000001)
文摘TiO2-coated SnO2 （TCS） hollow spheres, which are new anode materials for lithium ion （Li-ion） batteries, were prepared and characterized with X-ray diffraction （XRD）, scanning electron microscopy （SEM）, transmission electron microscopy （TEM）, cyclic voltammetry （CV）, and galvanostatic charge/discharge tests. The results obtained from XRD, SEM, and TEM show that TiO2 can be uniforrrdy coated on the surface of SnO2 hollow spheres with the assistance of anionic surfactant. The cyclic voltammograms indicate that both TiO2 and SnO2 exhibit the activity for Li-ion storage. The charge/discharge tests show that the prepared TCS hollow spheres have a higher reversible coulomb efficiency and a better cycling stability than the uncoated SnO2 hollow spheres.
基金Supported by the Program for Changjiang Scholars and Innovative Research Team in University (PCSIR0818)Health Ministry Foundation of China (WKJ2005-2-003)Natural Science Foundation of Fujian Province (2008H0089 and 2009J01025)
文摘The anti-bacterial adhesion properties of TiO2-coated polymethyl methacrylate （PMMA） surfaces are investigated systematically. In detail, the adhesion of S. aureus （gram positive） and E. coli （gram negative） to TiO2-coated and uncoated PMMA surfaces are performed by the plate counting method. Afterwards, the adhesion free energy of bacteria on both supporting materials is quantified using the thermodynamic approach of Lifshitz van der Waals and acid/base interactions. The superior anti-adhesion capability of TiO2-coated PMMA is demonstrated when compared to native PMMA, both experimentally and theoretically.
基金Supported by National Natural Science Foundation of China(Grant Nos.92160301,92060203,52175415,52205475)Science Center for Gas Turbine Project of China(Grant Nos.P2022-AB-IV-002-001,P2023-B-IV-003-001)+1 种基金Jiangsu Provincial Natural Science Foundation of China(Grant No.BK20210295)Graduate Research and Innovation Projects in Jiangsu Province of China(Grant No.KYCX22_0339).
文摘As an important green manufacturing process,dry grinding has problems such as high grinding temperature and insufficient cooling capacity.Aiming at the problems of sticking and burns in dry grinding of titanium alloys,grinding performance evaluation of molybdenum disulfide(MoS_(2))solid lubricant coated brazed cubic boron carbide(CBN)grinding wheel(MoS_(2)-coated CBN wheel)in dry grinding titanium alloys was carried out.The lubrication mechanism of MoS_(2)in the grinding process is analyzed,and the MoS_(2)-coated CBN wheel is prepared.The results show that the MoS_(2)solid lubricant can form a lubricating film on the ground surface and reduce the friction coefficient and grinding force.Within the experimental parameters,normal grinding force decreased by 42.5%,and tangential grinding force decreased by 28.1%.MoS_(2)lubricant can effectively improve the heat dissipation effect of titanium alloy grinding arc area.Compared with common CBN grinding wheel,MoS_(2)-coated CBN wheel has lower grinding temperature.When the grinding depth reaches 20μm,the grinding temperature decreased by 30.5%.The wear of CBN grains of grinding wheel were analyzed by mathematical statistical method.MoS_(2)lubricating coating can essentially decrease the wear of grains,reduce the adhesion of titanium alloy chip,prolong the service life of grinding wheel,and help to enhance the surface quality of workpiece.This research provides high-quality and efficient technical support for titanium alloy grinding.
文摘The simulation by the Monte Carlo method executed by the software PyPENELOPE proved effective to specify the particle propagation characteristics by calculating the absorption fractions, backscattering and transmission of electrons and secondary photons under the incidence of 0.5 to 20 KeV range of primary electrons. More than 99.9% of the primary electrons were transmitted in the 125 nm thick MgO/TiO<sub>2</sub> material at 20 KeV. This occurred because several interactions took place in the transmitted primary irradiation such as characteristic, fluorescence, and bremsstrahlung produced when of the occupation of the KL3, KL2, KM3, and KM2 shell and sub-shell of titanium and magnesium which are the elements with a high atomic number in the material. The transmission particle characteristic of this material is therefore an indicator capable of improving the electrical performance and properties of the sensor.
文摘This study focused on the development and characterization of TiO<sub>2</sub>-PES composite fibers with varying TiO<sub>2</sub> loading amounts using a phase inversion process. The resulting composite fibers exhibited a sponge-like structure with embedded TiO<sub>2</sub> nanoparticles within a polymer matrix. Their photocatalytic performance for ammonia removal from aqueous solutions under UV-A light exposure was thoroughly investigated. The findings revealed that PeTi8 composite fibers displayed superior adsorption capacity compared to other samples. Moreover, the study explored the impact of pH, light intensity, and catalyst dosage on the photocatalytic degradation of ammonia. Adsorption equilibrium isotherms closely followed the Langmuir model, with the results indicating a correlation between qm values of 2.49 mg/g and the porous structure of the adsorbents. The research underscored the efficacy of TiO<sub>2</sub> composite fibers in the photocatalytic removal of aqueous under UV-A light. Notably, increasing the distance between the photocatalyst and the light source resulted in de-creased hydroxyl radical concentration, influencing photocatalytic efficiency. These findings contribute to our understanding of TiO<sub>2</sub> composite fibers as promising photocatalysts for ammonia removal in water treatment applications.
文摘The photocatalytic degradation of the synthetic textile dye Reactive Yellow 145 (RY 145) in aqueous solution, using TiO2 coated non-woven fibers as photocatalyst, under UV-lamp irradiation, was studied. The effects of the operational parameters such as initial dye concentration, pH, addition of oxidant hydrogen peroxide and addition of ethanol on the reaction rate were investigated. The effect of some inorganic ions such as and , commonly present in real effluents, on the photodegradation of RY 145 was also examined. The experimental results showed that the photocatalytic degradation rate was favoured by a high concentration of solution in respect to Langmuir-Hinshelwood model. The maximum rate of complete decolorization of RY 145 was observed in the acidic medium at pH 3. The presence of and anions led to an increase of the effectiveness of the photocatalytic degradation. However, the presence of and anions decreased differently the photodegradation reaction rate. TiO2/UV process was proved to be capable of the complete degradation of the RY 145.
基金Supported by the Project of Shanghai Committee of Science and Technology,China(Nos.1052nm00100,09ZR1437600)
文摘Several lithium-ion batteries of 18650-type were assembled with pristine or Al2O3-coated LiNi0.4Co0.2Mn0.4O2（NCM） as cathode material and mesocarbon microbeads（MCMB） as anode material.The cycling performance of the batteries was examined under 25 °C at a 2C rate within a potential range of 2.75―4.20 V.The changes of the crystal structure,the lattice parameter,the mean crystallite size,and the mean micro-strain of pristine NCM and Al2O3-coated NCM during the charge-discharge cycling were determined by X-ray diffraction（XRD）.The results indicate that the bulk structure of Al2O3-coated NCM is more stable than that of pristine NCM,which leads to the better cycling performance of Al2O3-coated NCM compared to that of pristine NCM.
基金funded by a NASA Space Technology Research Fellowshipa Facilities Grant from the Institute for Materials Research(IMR)at The Ohio State University
文摘Growth of single-crystal Sn O_2 nanowires using a fluorine-doped Sn O_2(FTO) thin film as both the source and substrate is demonstrated for the first time at relatively low temperature(580 °C) which preserves the integrity of the underlying glass support and improves scalability to devices. Furthermore, a microwave hydrothermal process is shown to grow Ti O_2 nanorods on these nanowires to create a hierarchical nanoheterostructure that will lead to efficient photogenerated charge carrier separation and rapid transport of electrons to the substrate. This process simplifies nanowire growth by using commercially available and widely used FTO substrates without the need for an additional upstream Sn source and can be used as a high surface area host structure to many other hierarchical structures.
