Implant-related infections and tissue inflammation are the main factors for peri-implantitis.Lack of antibacterial activity and poor soft tissue sealing property increase the occurrence probability of peri-implantitis...Implant-related infections and tissue inflammation are the main factors for peri-implantitis.Lack of antibacterial activity and poor soft tissue sealing property increase the occurrence probability of peri-implantitis.To prevent and treat peri-implantitis,cerium-doped defective titanium oxide coatings are prepared on medical titanium surfaces by plasma electrolytic oxidation and thermal reduction treatment.In the darkness,Ce-doped defective titanium oxide coatings with micro-porous structure surface can inhibit the bacteria adhesion to some extent with antibacterial rates of 38.0%against S.aureus and 65.0%against E.coli.Under near infrared(NIR)irradiation,Ce-doped defective titanium oxide coatings show good photothermal antibacterial activity with antibacterial rates of 99.9%against S.aureus and 99.9%against E.coli.Moreover,with the increasing content of Ce-doping,the coatings exhibit higher capacity to scavenge hydrogen peroxide(H2O2)and 2,2′-azinobis-(3-ethylbenzothiazoline-6-sulfonic acid)radical cation(ABTS^(·+)).The coatings with enhanced antioxidant effect can protect human gingival fibroblasts from oxidative stress damage by eliminating reactive oxygen species and promoting initial cell adhesion.Besides,Ce-doped coatings can regulate the immune microenvironment by up-regulating the expression of anti-inflammatory genes and down-regulating the pro-inflammatory genes.In vivo animal experiments further confirm the good antibacterial activity of Ce-doped defective titanium oxide coatings under NIR irradiation and good biosafety.This work provides a novel surface modification strategy for implant abutment,which shows good application prospects for preventing and treating peri-implantitis.展开更多
Lithium-ion batteries(LIBs)that reached their end-of-life(EoL)require recycling,rather than disposal,to recirculate valuable metals and protect the environment.This led us to investigate the extraction of metals from ...Lithium-ion batteries(LIBs)that reached their end-of-life(EoL)require recycling,rather than disposal,to recirculate valuable metals and protect the environment.This led us to investigate the extraction of metals from the cathodes of EoL lithium-titanate batteries using ethylenediaminetetraacetic acid disodium(EDTA-2Na).In this work,an orthogonal array was used to design experiments and sig-nal-to-noise calculations were used to define the optimal conditions,which were 0.50 mol/L EDTA-2Na,pH=6,75℃,180 min,2%pulp density,and 300 r/min,resulting in 97.96%,94.79%,96.45%,and 98.89%leaching efficiencies for Li,Ni,Co,and Mn,respectively.Stat-istically significant interactions between variables were then identified using Pearson’s correlation at the 95%confidence interval,and the pH and temperature were found to be significant.The extraction efficiency decreased as the pH increased,but increased as the temperat-ure increased.Machine learning fitting using linear regression for multi-output prediction was unsatisfactory,whereas random forest re-gression(RFR)produced satisfactory results.Permutation importance was computed on the fitted RFR to determine feature importance,and confirmed that the pH and temperature were influential variables;however,the time and pulp density were also noted.As the fitted RFR failed to satisfactorily predict leaching efficiencies in additional validation experiments,we recommend increasing the number of ex-periments and using additional fitting models.An additional analysis that included the initial oxidation-reduction potential(optimal 33.3 mV)revealed this to be the most important variable,the effect of which largely overshadows those of all the other variables.Finally,an environmental assessment highlighted the benefits of the chelating extraction;however,the economic assessment indicated room for improvement.展开更多
In order to remove nitric oxides (NO) from flue gas, experimental studies on the photocatalytic oxidation (PCO) of NO are carried out in an efficient laboratory-scale reactor. Nano-sized TiO2 particles loading on ...In order to remove nitric oxides (NO) from flue gas, experimental studies on the photocatalytic oxidation (PCO) of NO are carried out in an efficient laboratory-scale reactor. Nano-sized TiO2 particles loading on quartz sand are prepared and used as the photocatalyst. Effects of several key operating parameters on NO conversion are investigated, including operating temperature, NO inlet concentration, oxygen percentage, relative humidity and residence time. The results illustrate that the NO inlet concentration, the oxygen percentage and the relative humidity play an important role in the oxidation of NO. A lower NO inlet concentration and a higher oxygen percentage result in a higher NO conversion efficiency. When the relative humidity is 8%, the maximum value of NO conversion efficiency is achieved. In addition, the operating temperature and the residence time have a little effect on the conversion efficiency of NO.展开更多
Titanium oxide thin films were prepared on self-assembled monolayers-coated silicon substrate using layer-by-layer self-assembly method and chemical bath deposition from an aqueous solution. The effects of temperature...Titanium oxide thin films were prepared on self-assembled monolayers-coated silicon substrate using layer-by-layer self-assembly method and chemical bath deposition from an aqueous solution. The effects of temperature on structural properties, thickness and morphologies of titanium oxide thin films were investigated. The results show that the absorption peak of peroxo complexes of titanium at 410 nm decreases gradually with increasing the temperature. The deposited films consisting of titanium oxide nanocrystals are believed to be fully amorphous by XRD. Titanium oxide thin films fabricated at 60 °C for 2 h are continuous, dense and homogeneous with a size in the range of 20-40 nm by SEM. The chemical compositions of deposited thin films were studied by EDS, and the mole ratio of O to Ti is 2.2:1.展开更多
Anodic oxide films of the titanium alloy Ti-10V-2Fe-3Al in ammonium tartrate electrolyte without hydrofluoric acid or fluoride were fabricated. The morphology, components, and microstructure of the films were characte...Anodic oxide films of the titanium alloy Ti-10V-2Fe-3Al in ammonium tartrate electrolyte without hydrofluoric acid or fluoride were fabricated. The morphology, components, and microstructure of the films were characterized by scanning electron microscopy (SEM), X-ray photoelectron spectroscopy (XPS), X-ray diffraction (XRD), and Raman spectroscopy. The results showed that the films were thick, uniform, and nontransparent. Such films exhibited sedimentary morphology, with a thickness of about 3 μm, and the pore diameters of the deposits ranged from several hundred nanometers to 1.5 μm. The films were mainly titanium dioxide. Some coke-like deposits, which may contain or be changed by OH, NH, C-C, C-O, and C=O groups, were doped in the films. The films were mainly amorphous with a small amount of anatase and rutile phase.展开更多
Effects of different facing oxides, including including yttria colloidal and powders (Y/Y), yttria stabilized zirconia colloidal and powders (ZY/ZY), zirconia colloidal and powders (Z/Z) and zirconia colloidal and zi...Effects of different facing oxides, including including yttria colloidal and powders (Y/Y), yttria stabilized zirconia colloidal and powders (ZY/ZY), zirconia colloidal and powders (Z/Z) and zirconia colloidal and zireonite powders (Z/ZS) on the qualities of investment castings are studied. The outward appearance, microstructures, and microhardness profiles of castings made of commercial pure titanium, Ti--Al--V and Ti--Al--Zr are investigated. Castings made by shells with yttria as face materials have the least contamination and by zirconite shells have the most contamination. Thermodynamic of metal-mold reactions is also taken into consideration.展开更多
The oxidation of thiophene by H_(2)O_(2)under mild conditions was difficult in the past,and it appears again with the proposed oxidative deep desulfurization(ODS)process to obtain ultralow sulfur fuel for fuel cell in...The oxidation of thiophene by H_(2)O_(2)under mild conditions was difficult in the past,and it appears again with the proposed oxidative deep desulfurization(ODS)process to obtain ultralow sulfur fuel for fuel cell industry and for environmental protection[1,2].The ODS process is very efficient in reducing ben-zothiophene,di-benzothiophene and their corresponding alkyl derivatives[1.2].However,thiophene and its alkyl derivatives,most of which exist in gasoline,are not removed in this process.展开更多
Effects of titanium oxide (TiO 2) nanoparticles on Bel-7402 human hepatoma cells and L-02 human hepatocytes at different times were observed.Using cell culture,cell growth curves of Bel-7402 cells and L-02 cells trea...Effects of titanium oxide (TiO 2) nanoparticles on Bel-7402 human hepatoma cells and L-02 human hepatocytes at different times were observed.Using cell culture,cell growth curves of Bel-7402 cells and L-02 cells treated with TiO 2 nanoparticles were examined by MTT assay,and the cellular ultrastructure was observed by an analytical transmission electron microscope (ATEM).It is found that OD value of Bel-7402 cell treated with TiO 2 nanoparticles for 48-144h is obviously lower than that of control group (p<0.01).However the growth curve of L-02 cells is almost not affected by TiO 2 nanoparticles.ATEM and energy dispersive X ray (EDX) analyses show that there are obvious vacuoles increased heterolysosome,and particles with high electron density which are confirmed to be TiO 2 nanoparticles in Bel-7402 cytoplasm.More interestingly,it is alse found that TiO 2 nanoparticle obviously inhibits the proliferation of hepatoma cells by altering lysosome activity and destroying cytoplasm structure.The inhibition on proliferation of hepatocytes by TiO 2 nanoparticles is much slighter.The results demonstrate that TiO 2 nanoparticle has different killing effects on cancer cell and normal cell.展开更多
Gallium-titanium-zinc oxide(GTZO) transparent conducting oxide(TCO) thin films were deposited on glass substrates by radio frequency magnetron sputtering. The dependences of the microstructure and optoelectronic prope...Gallium-titanium-zinc oxide(GTZO) transparent conducting oxide(TCO) thin films were deposited on glass substrates by radio frequency magnetron sputtering. The dependences of the microstructure and optoelectronic properties of GTZO thin films on Ar gas pressure were observed. The X-ray diffraction(XRD) and scanning electron microscopy(SEM) results show that all the deposited films are polycrystalline with a hexagonal structure and have a preferred orientation along the c-axis perpendicular to the substrate. With the increment of Ar gas pressure, the microstructure and optoelectronic properties of GTZO thin films will be changed. When Ar gas pressure is 0.4 Pa, the deposited films possess the best crystal quality and optoelectronic properties.展开更多
The different investigation has been carried out on the biological activities of titanium dioxide nanoparticle but the effect of this nano product on the antibacterial activity of different antibiotics has not been ye...The different investigation has been carried out on the biological activities of titanium dioxide nanoparticle but the effect of this nano product on the antibacterial activity of different antibiotics has not been yet demonstrated. In this study the nano size TiO2 is synthesized using citric acid and alpha dextrose and the enhancement effect of TiO2 nanoparticle on the antibacterial activity of different antibiotics was evaluated against Methicillin-resistant Staphylococcus aureus (MRSA). During the present study, different concentrations of nano-scale TiO2 were tested to find out the best concentration that can have the most effective antibacterial property against the MRSA culture. Disk diffusion method was used to determine the antibacterial activity of these antibiotics in the absence and presence of sub inhibitory concentration of TiO2 nano particle. A clinical isolate of MRSA, isolated from Intensive Care Unit (ICU) was used as test strain. In the presence of sub-inhibitory concentration of TiO2 nanoparticle (20 μg/disc) the antibacterial activities of all antibiotics have been increased against test strain with minimum 2 mm to maximum 10mm. The highest increase in inhibitory zone for MRSA was observed against pencillin G and amikacin (each 10 mm). Conversely, in case of nalidixic acid, TiO2 nanoparticle showed a Synergic effect on the antibacterial activity of this antibiotic against test strain. These results signify that the TiO2 nanoparticle potentate the antimicrobial action of beta lactums, cephalosporins, aminoglycosides, glycopeptides, macrolids and lincosamides, tetracycline a possible utilization of nano compound in combination effect against MRSA.展开更多
The chemical stripping method of titanium alloy oxide films was studied. An environment friendly solution hydrogen peroxide and sodium hydroxide without hydrofluoric acid or fluoride were used to strip the oxide films...The chemical stripping method of titanium alloy oxide films was studied. An environment friendly solution hydrogen peroxide and sodium hydroxide without hydrofluoric acid or fluoride were used to strip the oxide films. The morphologies of the surface and cross-section of the oxide films before and after the films stripping were characterized by using scanning electron microscopy (SEM). The microstructure and chemical compositions of the oxide films before and after the films stripping were investigated by using Raman spectroscopy (Raman) and X-ray photoelectron spectroscopy (XPS). It was shown that the thickness of the oxide film was in the range of 5-6 μm. The oxide films were stripped for 2 to 8 min in the solution. Moreover, the effect of the stripping time on the efficiency of the film stripping was investigated, and the optimum stripping time was between 6-8 min. When the stripping solution completely dissolved the whole film, the α/β microstructure of the titanium alloy Ti-10V-2Fe-3Al was partly revealed. The stripping mechanism was discussed in terms of the dissolution of film delamination. The hydrogen peroxide had a significant effect on the dissolution of the titanium alloy anodic oxide film. The feasibility of the dissolution reaction also was evaluated.展开更多
Micro arc oxidation(MAO) coatings doped with graphene oxide(GO) were prepared on pure titanium by adding GO and sodium dodecyl benzene sulfonate(SDBS) into a sodium silicate solution. The as-deposited coatings were co...Micro arc oxidation(MAO) coatings doped with graphene oxide(GO) were prepared on pure titanium by adding GO and sodium dodecyl benzene sulfonate(SDBS) into a sodium silicate solution. The as-deposited coatings were comparatively analyzed by scanning electron microscopy(SEM), energydispersive X-ray spectroscopy(EDS) and X-ray diffraction(XRD). The binding forces of the MAO, MAO+GO and MAO+GO+SDBS three coatings were measured by a scratch tester. The mechanical property of the three coatings was analyzed using the nano-indentation technique. The corrosion resistance of the coatings was tested by the electrochemical system in 3.5% NaCl solution. The photocatalytic activity of the prepared samples was evaluated by determining the degradation of methylene blue(MB) solution. The results showed that compared to the MAO coating, the morphologies and phase compositions of MAO+GO and MAO+GO+SDBS composite coatings were significantly different. These two composite coatings all had superior photocatalytic activity. Especially, the MAO+GO composite coating still had enhanced binding force and excellent corrosion resistance. Furthermore, the relationship between the microstructure and the properties of these three MAO coatings was analyzed.展开更多
Surface energy and work of adhesion of titanium oxide related materials were investigated.Titanium oxide(TiOx) films were deposited by electron-beam evaporation system using TiO2 as a source material.The films deposit...Surface energy and work of adhesion of titanium oxide related materials were investigated.Titanium oxide(TiOx) films were deposited by electron-beam evaporation system using TiO2 as a source material.The films deposited by various thickness and growth rate were etched subsequently by different plasma using various gases like Ar and O2.TiOx films were further modified by self-assembled monolayer(SAM)of silanes and ultraviolet(UV)irradiation.The surface modified TiOx films showed a wide range of water contact angles from 6.9°to 75.2°.The surface energies of Titania-related films and their work of adhesion with human blood were varied with different surface modification process.X-ray photoelectron spectroscopy(XPS)revealed that hydroxyl group present on the surface explains the hydrophilicity of the surface modified TiOx films.We also suggest that some surface modified samples can provide an excellent hemocompatible surface from the estimated work of adhesion between the surface modified TiOx samples and human blood.展开更多
Thin films of copper titanium oxide were deposited by metal organic chemical vapour deposition technique from the synthesized single solid source precursor, copper titanium acetylacatonate Cu [Ti(C5H7O2)3] at the depo...Thin films of copper titanium oxide were deposited by metal organic chemical vapour deposition technique from the synthesized single solid source precursor, copper titanium acetylacatonate Cu [Ti(C5H7O2)3] at the deposition temperature of 420°C. The deposited films were characterized using Rutherford Backscattering Spectroscopy, Scanning Electron Microscopy with Energy Dispersive X-Ray facility attached to it, X-Ray Diffractometry, UV-Visible Spectrometry and van-der Pauw Conductivity measurement. Results show that the thickness of the prepared film is determined as 101.236 nm and the film is amorphous in structure, having average grain size of approximately 1 μm. The optical behaviour showed that the absorption edge of the film was at 918 nm near infrared with corresponding direct energy band gap of 1.35 eV. The electrical characterization of the film gave the values of resistivity, sheet resistance and conductivity of the film as 3.43 × 10-1 Ω-cm, 3.39 × 106 Ω/square and 2.91 (Ω-cm)-1 respectively.展开更多
We present an enhancement of the fluorescence of shallow(<10 nm) nitrogen-vacancy(NV^-)centers by using atomic layer deposition to deposit titanium oxide layers on the diamond surface. In this way, the shallow NV-c...We present an enhancement of the fluorescence of shallow(<10 nm) nitrogen-vacancy(NV^-)centers by using atomic layer deposition to deposit titanium oxide layers on the diamond surface. In this way, the shallow NV-center charge states were stabilized, leading to the increasing fluorescence intensity of about 2 times. This surface coating technique could produce a protective layer of controllable thickness without any damages to the solid-state quantum system surface, which might be an approach to the further passivation or packaging techniques for the solid-state quantum devices.展开更多
The desulfurization and resulfurization of slag containing oxides of vanadium and titanium(CaO–SiO_(2)–MgO–Al_(2)O_(3)–V_(2)O_(3)–TiO_(2)–FeO)in the pretreatment of semi-steel desulfurization at 1623 K were inve...The desulfurization and resulfurization of slag containing oxides of vanadium and titanium(CaO–SiO_(2)–MgO–Al_(2)O_(3)–V_(2)O_(3)–TiO_(2)–FeO)in the pretreatment of semi-steel desulfurization at 1623 K were investigated.Based on the ionic structure theory of slag,it could be concluded that V_(2)O_(3) and TiO_(2) combined with(O_(2)–)to form complex anions including VO_(3)^(3–),TiO_(4)^(4–),etc.,which reduced the activity of(O_(2)–)and decreased the sulfur partition ratio(LS).And FeO enhanced the activity of[O]at the slag–metal interface,which decreased the desulfurization capacity of the slag.Compared to the binary basicity,the presented basicity expression containing V_(2)O_(3) and TiO_(2) described the relationship between LS and basicity more accurately.Considering the problems of dilute slag,a large amount of residual slag and much resulfurization in the slagging-off process after pretreatment,the effect of CaO+C-based slag modifier on the resulfurization,melting point and viscosity of the desulfurization slag was investigated.It was proposed that adding 5%–10%of the slag modifier to the desulfurization slag after desulfurization decreased the resulfurization effectively.And the added modifier adjusted the slag viscosity well,which helped to reduce iron loss and residual slag.展开更多
In this study,the workability of cement-based grouts containing n-TiO 2 nanoparticles and fly ash has been investigated experimentally.Several characteristic quantities(including,but not limited to,the marsh cone flow...In this study,the workability of cement-based grouts containing n-TiO 2 nanoparticles and fly ash has been investigated experimentally.Several characteristic quantities(including,but not limited to,the marsh cone flow time,the mini slump spreading diameter and the plate cohesion meter value)have been measured for different percentages of these additives.The use of fly ash as a mineral additive has been found to result in improvements in terms of workability behavior as expected.Moreover,if nano titanium oxide is also used,an improvement can be obtained regarding the bleeding values for the cement-based grout mixes.Using such experimental data,a multi-layer perceptron artificial neural network model has been developed(5 neurons in the hidden layer of the network model have been developed using a total of 42 experimental data).70%of the data employed in this model have been used for training,15%for validation and 15%for the test phase.The results demonstrate that the artificial neural network model can predict Marsh cone flow time,mini slump spreading diameter and plate cohesion meter values with an average error of 0.15%.展开更多
Niobium doped titanium oxide (TiO2) colloid was synthesized to fabricate a hydrogen gas sensor layer on oxidized silicon wafer substrate. The layers were obtained using spin coating technique and then heated in air at...Niobium doped titanium oxide (TiO2) colloid was synthesized to fabricate a hydrogen gas sensor layer on oxidized silicon wafer substrate. The layers were obtained using spin coating technique and then heated in air at 500°C for 30 min. The doping of TiO2 led to a significant enhancement of the sensitivity of the layer especially at low operating temperature. The effect of doping was found effective of operating the sensor at relatively low temperature (150°C). The layers show a very smooth nanostructure with average roughness of less than 0.5 nm. The behavior of the sensing characteristics of such layers was discussed related to their chemical compositions, morphology and their crystalline structure. The morphological and structural characteristics of the layers were studied through X-ray diffraction (XRD) and Atomic force microscopy (AFM).展开更多
A simple and effective method of removing polluted organics in water is reported here.Titanium dioxide is a catalyst in photo-oxidation of monocrotophos.The mechanism of photocatalytic oxidation and the kinetics of th...A simple and effective method of removing polluted organics in water is reported here.Titanium dioxide is a catalyst in photo-oxidation of monocrotophos.The mechanism of photocatalytic oxidation and the kinetics of the reaction were studied. This same principle also leads to the construction of instrument of PTR-FIA analysis for monitoring organic phosphorus and phosphate in water.展开更多
基金supported by the National Natural Science Foundation of China(No.52272283)the Science and Technology Commission of Shanghai Municipality(Nos.22S31902900 and 22ZR1457600)+3 种基金Youth Innovation Promotion Association CAS(No.2023263)Young Elite Scientists Sponsorship Program by CAST(No.2022-2024QNRC001)General Research Fund of the Research Grants Council(No.17207719)the Health and Medical Research Fund(No.20190244).
文摘Implant-related infections and tissue inflammation are the main factors for peri-implantitis.Lack of antibacterial activity and poor soft tissue sealing property increase the occurrence probability of peri-implantitis.To prevent and treat peri-implantitis,cerium-doped defective titanium oxide coatings are prepared on medical titanium surfaces by plasma electrolytic oxidation and thermal reduction treatment.In the darkness,Ce-doped defective titanium oxide coatings with micro-porous structure surface can inhibit the bacteria adhesion to some extent with antibacterial rates of 38.0%against S.aureus and 65.0%against E.coli.Under near infrared(NIR)irradiation,Ce-doped defective titanium oxide coatings show good photothermal antibacterial activity with antibacterial rates of 99.9%against S.aureus and 99.9%against E.coli.Moreover,with the increasing content of Ce-doping,the coatings exhibit higher capacity to scavenge hydrogen peroxide(H2O2)and 2,2′-azinobis-(3-ethylbenzothiazoline-6-sulfonic acid)radical cation(ABTS^(·+)).The coatings with enhanced antioxidant effect can protect human gingival fibroblasts from oxidative stress damage by eliminating reactive oxygen species and promoting initial cell adhesion.Besides,Ce-doped coatings can regulate the immune microenvironment by up-regulating the expression of anti-inflammatory genes and down-regulating the pro-inflammatory genes.In vivo animal experiments further confirm the good antibacterial activity of Ce-doped defective titanium oxide coatings under NIR irradiation and good biosafety.This work provides a novel surface modification strategy for implant abutment,which shows good application prospects for preventing and treating peri-implantitis.
基金supported by the National Research Foundation of Korea(NRF)grants funded by the Korea government(MSIT)(Nos.RS-2024-00406500 and RS-2024-00458682).
文摘Lithium-ion batteries(LIBs)that reached their end-of-life(EoL)require recycling,rather than disposal,to recirculate valuable metals and protect the environment.This led us to investigate the extraction of metals from the cathodes of EoL lithium-titanate batteries using ethylenediaminetetraacetic acid disodium(EDTA-2Na).In this work,an orthogonal array was used to design experiments and sig-nal-to-noise calculations were used to define the optimal conditions,which were 0.50 mol/L EDTA-2Na,pH=6,75℃,180 min,2%pulp density,and 300 r/min,resulting in 97.96%,94.79%,96.45%,and 98.89%leaching efficiencies for Li,Ni,Co,and Mn,respectively.Stat-istically significant interactions between variables were then identified using Pearson’s correlation at the 95%confidence interval,and the pH and temperature were found to be significant.The extraction efficiency decreased as the pH increased,but increased as the temperat-ure increased.Machine learning fitting using linear regression for multi-output prediction was unsatisfactory,whereas random forest re-gression(RFR)produced satisfactory results.Permutation importance was computed on the fitted RFR to determine feature importance,and confirmed that the pH and temperature were influential variables;however,the time and pulp density were also noted.As the fitted RFR failed to satisfactorily predict leaching efficiencies in additional validation experiments,we recommend increasing the number of ex-periments and using additional fitting models.An additional analysis that included the initial oxidation-reduction potential(optimal 33.3 mV)revealed this to be the most important variable,the effect of which largely overshadows those of all the other variables.Finally,an environmental assessment highlighted the benefits of the chelating extraction;however,the economic assessment indicated room for improvement.
基金The National High Technology Research Program of China (863 Program) (No. 2008AA05Z303)the Science and Technology Program of Jiangsu Province (No. BE2010184)the Environmental Protection Scientific Research Subject of Jiangsu Province (No.201031)
文摘In order to remove nitric oxides (NO) from flue gas, experimental studies on the photocatalytic oxidation (PCO) of NO are carried out in an efficient laboratory-scale reactor. Nano-sized TiO2 particles loading on quartz sand are prepared and used as the photocatalyst. Effects of several key operating parameters on NO conversion are investigated, including operating temperature, NO inlet concentration, oxygen percentage, relative humidity and residence time. The results illustrate that the NO inlet concentration, the oxygen percentage and the relative humidity play an important role in the oxidation of NO. A lower NO inlet concentration and a higher oxygen percentage result in a higher NO conversion efficiency. When the relative humidity is 8%, the maximum value of NO conversion efficiency is achieved. In addition, the operating temperature and the residence time have a little effect on the conversion efficiency of NO.
基金Projects(51204036,51234009)supported by the National Natural Science Foundation of ChinaProject(20110042120014)supported by the Research Fund for the Doctoral Program of Higher Education,China
文摘Titanium oxide thin films were prepared on self-assembled monolayers-coated silicon substrate using layer-by-layer self-assembly method and chemical bath deposition from an aqueous solution. The effects of temperature on structural properties, thickness and morphologies of titanium oxide thin films were investigated. The results show that the absorption peak of peroxo complexes of titanium at 410 nm decreases gradually with increasing the temperature. The deposited films consisting of titanium oxide nanocrystals are believed to be fully amorphous by XRD. Titanium oxide thin films fabricated at 60 °C for 2 h are continuous, dense and homogeneous with a size in the range of 20-40 nm by SEM. The chemical compositions of deposited thin films were studied by EDS, and the mole ratio of O to Ti is 2.2:1.
文摘Anodic oxide films of the titanium alloy Ti-10V-2Fe-3Al in ammonium tartrate electrolyte without hydrofluoric acid or fluoride were fabricated. The morphology, components, and microstructure of the films were characterized by scanning electron microscopy (SEM), X-ray photoelectron spectroscopy (XPS), X-ray diffraction (XRD), and Raman spectroscopy. The results showed that the films were thick, uniform, and nontransparent. Such films exhibited sedimentary morphology, with a thickness of about 3 μm, and the pore diameters of the deposits ranged from several hundred nanometers to 1.5 μm. The films were mainly titanium dioxide. Some coke-like deposits, which may contain or be changed by OH, NH, C-C, C-O, and C=O groups, were doped in the films. The films were mainly amorphous with a small amount of anatase and rutile phase.
文摘Effects of different facing oxides, including including yttria colloidal and powders (Y/Y), yttria stabilized zirconia colloidal and powders (ZY/ZY), zirconia colloidal and powders (Z/Z) and zirconia colloidal and zireonite powders (Z/ZS) on the qualities of investment castings are studied. The outward appearance, microstructures, and microhardness profiles of castings made of commercial pure titanium, Ti--Al--V and Ti--Al--Zr are investigated. Castings made by shells with yttria as face materials have the least contamination and by zirconite shells have the most contamination. Thermodynamic of metal-mold reactions is also taken into consideration.
文摘The oxidation of thiophene by H_(2)O_(2)under mild conditions was difficult in the past,and it appears again with the proposed oxidative deep desulfurization(ODS)process to obtain ultralow sulfur fuel for fuel cell industry and for environmental protection[1,2].The ODS process is very efficient in reducing ben-zothiophene,di-benzothiophene and their corresponding alkyl derivatives[1.2].However,thiophene and its alkyl derivatives,most of which exist in gasoline,are not removed in this process.
基金FundedbytheNationalNaturalScienceFoundationofChina (No :39770 2 2 5 )
文摘Effects of titanium oxide (TiO 2) nanoparticles on Bel-7402 human hepatoma cells and L-02 human hepatocytes at different times were observed.Using cell culture,cell growth curves of Bel-7402 cells and L-02 cells treated with TiO 2 nanoparticles were examined by MTT assay,and the cellular ultrastructure was observed by an analytical transmission electron microscope (ATEM).It is found that OD value of Bel-7402 cell treated with TiO 2 nanoparticles for 48-144h is obviously lower than that of control group (p<0.01).However the growth curve of L-02 cells is almost not affected by TiO 2 nanoparticles.ATEM and energy dispersive X ray (EDX) analyses show that there are obvious vacuoles increased heterolysosome,and particles with high electron density which are confirmed to be TiO 2 nanoparticles in Bel-7402 cytoplasm.More interestingly,it is alse found that TiO 2 nanoparticle obviously inhibits the proliferation of hepatoma cells by altering lysosome activity and destroying cytoplasm structure.The inhibition on proliferation of hepatocytes by TiO 2 nanoparticles is much slighter.The results demonstrate that TiO 2 nanoparticle has different killing effects on cancer cell and normal cell.
基金supported by the National Natural Science Foundation of China(No.11504436)the Natural Science Foundation of Hubei Province(No.2015CFB364)the Fundamental Research Funds for the Central Universities(Nos.CZW14019 and CZW15045)
文摘Gallium-titanium-zinc oxide(GTZO) transparent conducting oxide(TCO) thin films were deposited on glass substrates by radio frequency magnetron sputtering. The dependences of the microstructure and optoelectronic properties of GTZO thin films on Ar gas pressure were observed. The X-ray diffraction(XRD) and scanning electron microscopy(SEM) results show that all the deposited films are polycrystalline with a hexagonal structure and have a preferred orientation along the c-axis perpendicular to the substrate. With the increment of Ar gas pressure, the microstructure and optoelectronic properties of GTZO thin films will be changed. When Ar gas pressure is 0.4 Pa, the deposited films possess the best crystal quality and optoelectronic properties.
文摘The different investigation has been carried out on the biological activities of titanium dioxide nanoparticle but the effect of this nano product on the antibacterial activity of different antibiotics has not been yet demonstrated. In this study the nano size TiO2 is synthesized using citric acid and alpha dextrose and the enhancement effect of TiO2 nanoparticle on the antibacterial activity of different antibiotics was evaluated against Methicillin-resistant Staphylococcus aureus (MRSA). During the present study, different concentrations of nano-scale TiO2 were tested to find out the best concentration that can have the most effective antibacterial property against the MRSA culture. Disk diffusion method was used to determine the antibacterial activity of these antibiotics in the absence and presence of sub inhibitory concentration of TiO2 nano particle. A clinical isolate of MRSA, isolated from Intensive Care Unit (ICU) was used as test strain. In the presence of sub-inhibitory concentration of TiO2 nanoparticle (20 μg/disc) the antibacterial activities of all antibiotics have been increased against test strain with minimum 2 mm to maximum 10mm. The highest increase in inhibitory zone for MRSA was observed against pencillin G and amikacin (each 10 mm). Conversely, in case of nalidixic acid, TiO2 nanoparticle showed a Synergic effect on the antibacterial activity of this antibiotic against test strain. These results signify that the TiO2 nanoparticle potentate the antimicrobial action of beta lactums, cephalosporins, aminoglycosides, glycopeptides, macrolids and lincosamides, tetracycline a possible utilization of nano compound in combination effect against MRSA.
基金Funded by the National Natural Science Foundation of China(No. 51171011)
文摘The chemical stripping method of titanium alloy oxide films was studied. An environment friendly solution hydrogen peroxide and sodium hydroxide without hydrofluoric acid or fluoride were used to strip the oxide films. The morphologies of the surface and cross-section of the oxide films before and after the films stripping were characterized by using scanning electron microscopy (SEM). The microstructure and chemical compositions of the oxide films before and after the films stripping were investigated by using Raman spectroscopy (Raman) and X-ray photoelectron spectroscopy (XPS). It was shown that the thickness of the oxide film was in the range of 5-6 μm. The oxide films were stripped for 2 to 8 min in the solution. Moreover, the effect of the stripping time on the efficiency of the film stripping was investigated, and the optimum stripping time was between 6-8 min. When the stripping solution completely dissolved the whole film, the α/β microstructure of the titanium alloy Ti-10V-2Fe-3Al was partly revealed. The stripping mechanism was discussed in terms of the dissolution of film delamination. The hydrogen peroxide had a significant effect on the dissolution of the titanium alloy anodic oxide film. The feasibility of the dissolution reaction also was evaluated.
基金Funded by the National Natural Science Foundation of China(No.51571114)the Key Research and Development Plan of Shaanxi Province-Industrial Project(No.2018GY-127)
文摘Micro arc oxidation(MAO) coatings doped with graphene oxide(GO) were prepared on pure titanium by adding GO and sodium dodecyl benzene sulfonate(SDBS) into a sodium silicate solution. The as-deposited coatings were comparatively analyzed by scanning electron microscopy(SEM), energydispersive X-ray spectroscopy(EDS) and X-ray diffraction(XRD). The binding forces of the MAO, MAO+GO and MAO+GO+SDBS three coatings were measured by a scratch tester. The mechanical property of the three coatings was analyzed using the nano-indentation technique. The corrosion resistance of the coatings was tested by the electrochemical system in 3.5% NaCl solution. The photocatalytic activity of the prepared samples was evaluated by determining the degradation of methylene blue(MB) solution. The results showed that compared to the MAO coating, the morphologies and phase compositions of MAO+GO and MAO+GO+SDBS composite coatings were significantly different. These two composite coatings all had superior photocatalytic activity. Especially, the MAO+GO composite coating still had enhanced binding force and excellent corrosion resistance. Furthermore, the relationship between the microstructure and the properties of these three MAO coatings was analyzed.
基金Fundamental Research Funds for the Central Universities(N090403002)
文摘Surface energy and work of adhesion of titanium oxide related materials were investigated.Titanium oxide(TiOx) films were deposited by electron-beam evaporation system using TiO2 as a source material.The films deposited by various thickness and growth rate were etched subsequently by different plasma using various gases like Ar and O2.TiOx films were further modified by self-assembled monolayer(SAM)of silanes and ultraviolet(UV)irradiation.The surface modified TiOx films showed a wide range of water contact angles from 6.9°to 75.2°.The surface energies of Titania-related films and their work of adhesion with human blood were varied with different surface modification process.X-ray photoelectron spectroscopy(XPS)revealed that hydroxyl group present on the surface explains the hydrophilicity of the surface modified TiOx films.We also suggest that some surface modified samples can provide an excellent hemocompatible surface from the estimated work of adhesion between the surface modified TiOx samples and human blood.
文摘Thin films of copper titanium oxide were deposited by metal organic chemical vapour deposition technique from the synthesized single solid source precursor, copper titanium acetylacatonate Cu [Ti(C5H7O2)3] at the deposition temperature of 420°C. The deposited films were characterized using Rutherford Backscattering Spectroscopy, Scanning Electron Microscopy with Energy Dispersive X-Ray facility attached to it, X-Ray Diffractometry, UV-Visible Spectrometry and van-der Pauw Conductivity measurement. Results show that the thickness of the prepared film is determined as 101.236 nm and the film is amorphous in structure, having average grain size of approximately 1 μm. The optical behaviour showed that the absorption edge of the film was at 918 nm near infrared with corresponding direct energy band gap of 1.35 eV. The electrical characterization of the film gave the values of resistivity, sheet resistance and conductivity of the film as 3.43 × 10-1 Ω-cm, 3.39 × 106 Ω/square and 2.91 (Ω-cm)-1 respectively.
基金National Natu- ral Science Foundation of China (No.11374280 and No.50772110). The authors wish to thank Guo-ping Guo, Jie You and Yang Li from the Key Lab of Quan- tum Information for the support of electron beam lithography. We also thank Ming-ling Li at University of Science and Technology of China for the technical support of ALD.
文摘We present an enhancement of the fluorescence of shallow(<10 nm) nitrogen-vacancy(NV^-)centers by using atomic layer deposition to deposit titanium oxide layers on the diamond surface. In this way, the shallow NV-center charge states were stabilized, leading to the increasing fluorescence intensity of about 2 times. This surface coating technique could produce a protective layer of controllable thickness without any damages to the solid-state quantum system surface, which might be an approach to the further passivation or packaging techniques for the solid-state quantum devices.
文摘The desulfurization and resulfurization of slag containing oxides of vanadium and titanium(CaO–SiO_(2)–MgO–Al_(2)O_(3)–V_(2)O_(3)–TiO_(2)–FeO)in the pretreatment of semi-steel desulfurization at 1623 K were investigated.Based on the ionic structure theory of slag,it could be concluded that V_(2)O_(3) and TiO_(2) combined with(O_(2)–)to form complex anions including VO_(3)^(3–),TiO_(4)^(4–),etc.,which reduced the activity of(O_(2)–)and decreased the sulfur partition ratio(LS).And FeO enhanced the activity of[O]at the slag–metal interface,which decreased the desulfurization capacity of the slag.Compared to the binary basicity,the presented basicity expression containing V_(2)O_(3) and TiO_(2) described the relationship between LS and basicity more accurately.Considering the problems of dilute slag,a large amount of residual slag and much resulfurization in the slagging-off process after pretreatment,the effect of CaO+C-based slag modifier on the resulfurization,melting point and viscosity of the desulfurization slag was investigated.It was proposed that adding 5%–10%of the slag modifier to the desulfurization slag after desulfurization decreased the resulfurization effectively.And the added modifier adjusted the slag viscosity well,which helped to reduce iron loss and residual slag.
基金funded by The Scientific and Technological Research Council of Turkey-TUBITAK[Grant No.219M522].
文摘In this study,the workability of cement-based grouts containing n-TiO 2 nanoparticles and fly ash has been investigated experimentally.Several characteristic quantities(including,but not limited to,the marsh cone flow time,the mini slump spreading diameter and the plate cohesion meter value)have been measured for different percentages of these additives.The use of fly ash as a mineral additive has been found to result in improvements in terms of workability behavior as expected.Moreover,if nano titanium oxide is also used,an improvement can be obtained regarding the bleeding values for the cement-based grout mixes.Using such experimental data,a multi-layer perceptron artificial neural network model has been developed(5 neurons in the hidden layer of the network model have been developed using a total of 42 experimental data).70%of the data employed in this model have been used for training,15%for validation and 15%for the test phase.The results demonstrate that the artificial neural network model can predict Marsh cone flow time,mini slump spreading diameter and plate cohesion meter values with an average error of 0.15%.
文摘Niobium doped titanium oxide (TiO2) colloid was synthesized to fabricate a hydrogen gas sensor layer on oxidized silicon wafer substrate. The layers were obtained using spin coating technique and then heated in air at 500°C for 30 min. The doping of TiO2 led to a significant enhancement of the sensitivity of the layer especially at low operating temperature. The effect of doping was found effective of operating the sensor at relatively low temperature (150°C). The layers show a very smooth nanostructure with average roughness of less than 0.5 nm. The behavior of the sensing characteristics of such layers was discussed related to their chemical compositions, morphology and their crystalline structure. The morphological and structural characteristics of the layers were studied through X-ray diffraction (XRD) and Atomic force microscopy (AFM).
文摘A simple and effective method of removing polluted organics in water is reported here.Titanium dioxide is a catalyst in photo-oxidation of monocrotophos.The mechanism of photocatalytic oxidation and the kinetics of the reaction were studied. This same principle also leads to the construction of instrument of PTR-FIA analysis for monitoring organic phosphorus and phosphate in water.