Gene/Protein
Disease
Symptom
Drug
Enzyme
Compound
Pivot Concepts:
Gene/Protein
Disease
Symptom
Drug
Enzyme
Compound
Target Concepts:
Gene/Protein
Disease
Symptom
Drug
Enzyme
Compound
Query: KEGG:D01931 (
TiO2
)
11,320
document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)
The pure titanium disks were divided into three groups and etched for 30 minutes with
HNO3
, hot H2SO4/H2O2 or hot H2SO4/HCl respectively. The treated disks were studied and analyzed with scanning electron microscope (SEM) and X-ray photoelectron spectroscopy (XPS). The disks etched with
HNO3
had a smooth surface, while those etched with hot H2SO4/H2O2 or hot H2SO4/HCl had rough surfaces, and the surface etched with hot H2SO4/HCl had larger micropores. The XPS analysis demonstrated that the main elements of the surface in three groups were titanium, oxygen and carbon. The carbon concentration was the lowest on the surface etched with hot H2SO4/H2O2 and the highest on that etched with hot H2SO4/HCl. The substances were
TiO2
, Ti2O3, TiO and metal Ti on the surface etched with
HNO3
or hot H2SO4/H2O2. Only
TiO2
was detected on the surface etched with hot H2SO4/HCl.
...
PMID:[Effects of three different etching methods on surface morphology and element of pure titanium]. 1700 14
A new method has been developed for the determination of gold based on separation and preconcentration with a microcolumn packed with nanometer
TiO2
immobilized on silica gel (immobilized nanometer
TiO2
) prior to its determination by flame atomic absorption spectrometry. The optimum experimental parameters for preconcentration of gold, such as pH of the sample, sample flow rate and volume, eluent and interfering ions, have been investigated. Gold could be quantitatively retained by immobilized nanometer
TiO2
in the pH range of 8-10, then eluted completely with 0.1 mol L(-1)
HNO3
. The detection limit of this method for Au was 0.21 ng mL(-1) with an enrichment factor of 50, and the relative standard deviation (R.S.D.) was 1.8% at the 100 ng mL(-1) Au level. The method has been applied for the determination of trace amounts of Au in geological and water samples with satisfactory results.
...
PMID:Determination of gold by nanometer titanium dioxide immobilized on silica gel packed microcolumn and flame atomic absorption spectrometry in geological and water samples. 1799 31
The direct determination method of trace composition, Fe2O3,
TiO2
, MnO, K2O, Na2O, CaO and MgO, and impurity elements, Pb, Cr, Cd, Cu and As, in kaolin was studied by using inductive coupled plasma mass spectrometry (ICP-MS). After the samples were dissolved completely in HF-
HNO3
at low temperature, silicon was volatilized in the form of SiF4 and separated from the solution. Then the solution was continually evaporated to dry to get the solid substance which was dissolved by the nitric acid (1+3). The internal elements 45Sc, 115In and 205Tl were added on line and the effect of matrix, interface and fluctuation of instrument was overcome effectively by using internal standard calibration method. By choosing the optional operating parameters and appropriate isotopes of element to be detected, the influence of mass spectrometry interference was conquered effectively. The effect of temperature in samples preparation on the determination of arsenic was tested. The recovery for spiking sample is in the range from 95.0% to 101.0% and the relative standard deviation is in the range from 1.1% to 2.01%. In order to check the accuracy of the method, the kaolin standard reference material GBW03122 was also analyzed, and the analytical values conformed to standard values. This method has the characteristics of being simple, rapid and accurate, and can be used in the testing of trace composition and impurity elements in kaolin and ceramic product.
...
PMID:[Study on the determination of trace composition and impurity elements in kaolin with ICP-MS]. 1944 38
An anatase
TiO2
and three kinds of novel
TiO2
nanoparticles were prepared by a hydrothermal method for dye-sensitized solar cells (DSSCs), which were obtained by mixing NaOH (10 M), KOH (14 M) and LiOH (10 M) solution with an anatase
TiO2
powder, respectively. The
TiO2
working electrodes of DSSCs were prepared and the photoelectric properties of the cells were characterized. The influence of different poly(ethylene glycol) contents in
TiO2
films with and without
HNO3
treatment on the electron transfer in DSSCs were investigated. It is found that the DSSC with
HNO3
(0.002 mol/l)-treated film containing 16.7 wt% PEG shows the higher power conversion efficiency of 6.0%, which was mainly depended on the degrees of
TiO2
pore size and uniformity of
TiO2
films.
...
PMID:Enhanced efficiency of dye-sensitized solar cells with novel synthesized TiO2. 2035 13
A nano-structured film composed of
TiO2
and reduced graphite oxide (GO) was synthesized on ITO glass via a typical electrochemical route. A mixed solvent of Ti(SO4)2 and GO was prepared, with the addition of H2O2,
HNO3
and DMF at different ratio. A setup of two electrodes of ITO glass in a plastic cell and an electrochemical analyzer is used for the film forming. The film is characterized with a microstructure of GO plates being perpendicular to the glass substrate, since GO in the electrolyte solvent is separated as small plates at about several nanometers in diameter.
TiO2
is found being deposited between these GO plates. This microstructure is quite different from the film formed by normal deposition, where the GO plates are generally parallel to the substrate. The oxygen containing groups of C=O, C-O-C and C-OH on the GO surface are reduced because of neighboring to
TiO2
, it means two phases being bonded to each other at the interface. The photoelectric current of the composite film is compared with the pure
TiO2
film, the former one is almost one time higher than the latter one. The degradation of methyl orange of two kinds of film is also analyzed under the irradiation of ultraviolet light. The photocatalytic activity of two kinds of film presents the same trend of variation as that of photoelectric current. These results suggest that the photoexcited electrons of
TiO2
may quickly transfer to the glass substrate through the reduced GO neighbor, that owns a better conductivity, and so far decrease the recovery of excited electron-hole. The unordinary microstructure of the composite film may favor both to the electron transmission between the GO and ITO glass substrate, and to the light excitation of
TiO2
. The microstructure of different films was studies by AFM, XPS, FESEM. The photo-electrochemical property was measured by an electrochemical instrument Model CHI660C with Blupoint4 as a UV light source.
...
PMID:Synthesis of TiO2/GO composite film via an electrochemical route. 2113 73
TiO2
films were prepared on glass substrates using the sol-gel process for a dye-sensitized solar cell application. The
TiO2
sol was prepared using hydrolysis/polycondensation. Titanium (IV) Tetra Isopropoxide (TTIP) was used as precursor and Nitric acid (
HNO3
) was used as a catalyst for the peptization. The crystal structure and morphology of the prepared materials were characterized by XRD, and an SEM. The observations confirmed the nanocrystalline nature of the
TiO2
. The reaction parameters, such as the catalyst concentrations, the calcination time, and the calcination temperature were varied during the synthesis in order to achieve nanosize
TiO2
particles. The prepared
TiO2
particles were coated onto FTO glass using a screen printing technique. The prepared
TiO2
films were characterized by UV-vis. The
TiO2
particles calcinated at low temperatures showed an anatase phase they grew into a rutile phase when the calcination temperature increased. The size and structure of the
TiO2
particles were adjusted to specific surface areas. It was found that the conversion efficiency of the DSSC was highly affected by the properties of the
TiO2
particles.
...
PMID:Nanostructured TiO2 films for dye-sensitized solar cells prepared by the sol-gel method. 2240 37
Three-dimensional (3D)
TiO2
hierarchical structures with various microstructures have been successfully synthesized via a surfactant-free and single-step solvothermal route, in which hydrochloric acid (HCl), nitric acid (
HNO3
), and acetic acid (HAc) are employed as the acid medium, respectively. The effects of acid medium on the microstructures and properties of 3D
TiO2
hierarchical structure have been studied. The results indicate that 3D dandelion-like microspheres assembled of radial rutile nanorods are obtained in the sample prepared with HCl. Both the fraction of rutile and the diameter of nanorod enhance with the increasing HCl concentration. For the products derived from either
HNO3
or HAc, 3D spheres composed of anatase nanoparticles are present. The 3D dandelion-like
TiO2
hierarchical structures show low reflectance and efficient light harvesting since this ordered rod geometry offers a light-transfer path for incident light as well as multiple reflective and scattering effects. Moreover, 3D
TiO2
with this unique topology shows superior photocatalytic activity despite low surface area, which can be ascribed to the enhanced light harvesting, fast electron transport, and low electron/hole recombination loss.
...
PMID:Effects of acid on the microstructures and properties of three-dimensional TiO2 hierarchical structures by solvothermal method. 2250 Sep 85
TiO2
nanofiber consisting of 15 +/- 5 nm anatase grains was synthesized by hydrothermal treatment of fibrous hydrogen titanate precursor at 180 degrees C for 20 h. The hydrogen titanate precursor was synthesized by hydrothermal treatment of commercial P25
TiO2
powder in 10 M NaOH at 200 degrees C for 20 h followed by soaking in 0.1 M
HNO3
to perform ion exchange between the as-synthesized Na titanate and H. By controlling pH of the solution during hydrothermal treatment of the hydrogen titanate precursor, pure anatase
TiO2
nanofiber was obtained. Its band-gap energy determined from the onset of diffused reflectance spectrum was 3.19 eV which is equal to that of anatase
TiO2
powder. The
TiO2
nanofiber showed higher photodecomposition efficiency than the Cotiox KA-100
TiO2
but lower than the P25
TiO2
. Photodegradation is the predominant process for 'Reactive blue 171' removal.
...
PMID:Hydrothermal synthesis and photocatalytic activity of anatase TiO2 nanofiber. 2290 66
Metastable hexagonal MoO3 microrods were grown from bulk MoS2 and used as support materials for MoS2 and
TiO2
nanoparticles. The hybrid composites that consisted of MoO3, MoS2, and
TiO2
were prepared at a low temperature using the one-step synthesis method. The crystallinity and morphology of the MoO3/MoS2/
TiO2
composites that were prepared using
HNO3
and titanium tetraisopropoxide were compared with those of the MoO3/MoS2 composites that were prepared without titanium tetraisopropoxide. Titanium isopropoxide facilitated the formation of the MoO3 microrods from the oxidation of the bulk MoS2. The desired MoO3/MoS2/
TiO2
composites were obtained using 0.5 g of bulk MoS2, 3-4 ml of
HNO3
, and 0.367 ml of titanium tetraisopropoxide. The MoO3/MoS2/
TiO2
composites that were treated with ultrasonic waves showed rapid degradation of the methylene blue solution (2 x 10(-4) M) in the dark and good photocatalytic ability under ultraviolet light irradiation. The decomposition of methylene blue depended on the composition of the composite.
...
PMID:Preparation of MoO3/MoS2/TiO2 composites for catalytic degradation of methylene blue. 2296 75
As an important precursor of hydroxyl radical, nitrous acid (HONO) plays a key role in the chemistry of the lower atmosphere. Recent atmospheric measurements and model calculations show strong enhancement for HONO formation during daytime, while they are inconsistent with the known sources in the atmosphere, suggesting that current models are lacking important sources for HONO. In this article, heterogeneous photochemical reactions of nitric acid/nitrate anion and nitrogen oxide on various aerosols were reviewed and their potential contribution to HONO formation was also discussed. It is demonstrated that HONO can be formed by photochemical reaction on surfaces with deposited
HNO3
, by photocatalytic reaction of NO2 on
TiO2
or
TiO2
-containing materials, and by photochemical reaction of NO2 on soot, humic acids or other photosensitized organic surfaces. Although significant uncertainties still exist in the exact mechanisms and the yield of HONO, these additional sources might explain daytime observations in the atmosphere.
...
PMID:Review of heterogeneous photochemical reactions of NOy on aerosol - A possible daytime source of nitrous acid (HONO) in the atmosphere. 2359 53
<< Previous
1
2
3
Next >>