Photochromic Characteristics of Tungsten Trioxide Films Prepared by Electric Current Heating Using Tungsten Wire

2009 ◽  
Vol 421-422 ◽  
pp. 364-367 ◽  
Author(s):  
Takumi Hagizawa ◽  
Takayuki Honma ◽  
Yuichiro Kuroki ◽  
Tomoichiro Okamoto ◽  
Masasuke Takata
Keyword(s):  
Particle Size ◽  
Electric Current ◽  
Wavelength Range ◽  
Uv Irradiation ◽  
Glass Substrate ◽  
Tungsten Trioxide ◽  
Tungsten Wire ◽  
Absorption Peak ◽  
Heating Method ◽  
Peak Intensity

Tungsten trioxide films were deposited on the glass substrate by electric current heating method using tungsten wire in air. Applied voltages to the tungsten wire were increased at rates of 0.05, 0.5, 5 and 50 V/min. The resultant films consisted of particles. A particle size of the crystals increased with increasing voltage applying rate. The effects of an ultraviolet (UV) irradiation on the reflectance of the films were investigated. The reflectance in the wavelength range of 500 - 2500 nm decreased by the irradiation. When the films were left in dark after the irradiation, the reflectance returned to the initial. With increasing voltage applying rate, absorption peak shifted toward longer wavelength in the region of 1250 - 1500 nm and the peak intensity decreased.

Relationship between particle size and photochromic characteristics of tungsten oxide films prepared by electric current heating method using tungsten wire

2013 ◽  
Vol 39 (3) ◽  
pp. 2851-2855 ◽  
Author(s):  
Takumi Hagizawa ◽  
Takayuki Honma ◽  
Yuichiro Kuroki ◽  
Tomoichiro Okamoto ◽  
Masasuke Takata
Keyword(s):  
Particle Size ◽  
Tungsten Oxide ◽  
Electric Current ◽  
Tungsten Wire ◽  
Oxide Films ◽  
Heating Method

Synthesis of Cubic Ni Nanoparticles by Electric Current Heating Method Using Ni Wire

2012 ◽  
Vol 512-515 ◽  
pp. 132-135
Author(s):  
Ikuhisa Tada ◽  
Tomoichiro Okamoto ◽  
Yuichiro Kuroki ◽  
Takumi Hagizawa ◽  
Keiichiro Oh-Ishi ◽  
...  
Keyword(s):  
Thin Films ◽  
Electric Current ◽  
Glass Substrate ◽  
Oxygen Atmosphere ◽  
Starting Material ◽  
Nickel Wire ◽  
Ni Nanoparticles ◽  
Heating Method ◽  
Peak Intensity ◽  
The Wire

Nickel wire was used as a starting material to fabricate Ni nanoparticles. A glass substrate was placed above the wire to deposit the particles. The wire was heated by applying a d. c. voltage in the range of 2.2 ~ 4.0 V in oxygen atmosphere until the wire broke. White deposits were observed on the substrate after the heating. The TEM observation revealed that the deposits consisted of cubic nanoparticles with the edge lengths of 2 ~ 200 nm. The size of the particle tended to decrease with decreasing voltage. The particles were covered with films of approximately 4 nm in thickness. After reducing in hydrogen at 250°C for 30 min, the thickness of the films on the cubic particles decreased and the XRD peak intensity attributed to NiO decreased. Consequently the particles were found to be cubic Ni nanoparticles covered with NiO thin films.

Cathodoluminescence of ZnO Crystals Prepared via Electric Current Heating Method Using Zn Wire

2011 ◽  
Vol 485 ◽  
pp. 261-264 ◽  
Author(s):  
Takumi Hagizawa ◽  
Yuichiro Kuroki ◽  
Tomoichiro Okamoto ◽  
Masasuke Takata
Keyword(s):  
Electric Current ◽  
Joule Heating ◽  
Glass Substrate ◽  
Crystal Size ◽  
Green Emission ◽  
Peak Intensity Ratio ◽  
Heating Method ◽  
Uv Emission ◽  
Peak Intensity ◽  
The Wire

Zn wire was used as starting material in the fabrication of ZnO crystals in which a glass substrate was placed above the wire to grow ZnO crystals. The wire was heated by electric current in air. When the wire broke because of Joule heating, smoke arose from the wire and ZnO crystals were observed on the broken point, in the vicinity of the broken point, and on the glass substrate. The morphology and cathodoluminescence of the crystals were investigated. The crystals on the wire were 0.2–5 μm in size. The peak intensity ratio of ultraviolet (UV) emission to green emission increased with decreasing crystal size. The crystals on the substrate were tetrapod-like; the length and diameter of the tetrapod legs were 100–500 nm and 10–30 nm, respectively. The tetrapod-like nanocrystals produced only UV emissions.

scholarly journals Fotodegradasi High Density Polyethylene Yang Mengandung Aditif Okso-Biodegradasi

2017 ◽  
Vol 4 (2) ◽  
pp. 402-405
Author(s):  
Ristika O. Asriza ◽  
Janiar Pitulima
Keyword(s):  
Mechanical Properties ◽  
Carbonyl Group ◽  
Wavelength Range ◽  
High Density Polyethylene ◽  
Room Temperature ◽  
Uv Light ◽  
High Density ◽  
Absorption Peak ◽  
Metal Compound ◽  
Peak Intensity

High Density Polyethylene (HDPE) is a type of plastic that widely used for packaging because it has good mechanical properties. HDPE is naturally non-biodegradable, and  the consequence it will increase plastic waste that will damage the environment. To increase their biodegradability, it is necessary to add an oxo-biodegradation additive in the form of a stearate metal compound. This oxo-biodegradation additive is a chromophore that can absorb UV light. Polyethylene oxo-biodegradation films are prepared by mixing HDPE and cobalt stearate to homogeneous on various compositions. To know the effect of adding cobalt stearate into HDPE has done by photodegradation  process. The polyethylene oxo-biodegradation film was given irradiation using UV light in the wavelength range 280-300 nm at room temperature for 10 days. After irradiation, in the ATR spectrum shows an absorption  peak at 1712 cm-1 wavenumber indicatied  the presence of a carbonyl group with a stronger intensity. The higher concentration of cobalt stearate added in HDPE, increases the peak intensity of carbonyl group. This is due to the increasing number of chromophores from cobalt stearate that can absorb UV light, the faster the breakdown of HDPE chains into small fragments so that HDPE is rapidly degraded in nature.

scholarly journals Pseudo-Continuous Flow FTIR System for Glucose, Fructose and Sucrose Identification in Mid-IR Range

Micromachines ◽  
2018 ◽  
Vol 9 (10) ◽  
pp. 517 ◽  
Author(s):  
Hamza Landari ◽  
Mourad Roudjane ◽  
Younès Messaddeq ◽  
Amine Miled
Keyword(s):  
Absorption Spectrum ◽  
Measurement Error ◽  
Wavelength Range ◽  
Continuous Flow ◽  
Flow System ◽  
Microfluidic System ◽  
Sample Distribution ◽  
Peak Intensity ◽  
Conventional Systems

In this paper, we present a new FTIR-based microfluidic system for Glucose, Fructose and Sucrose detection. The proposed microfluidic system is based on a pseudo-continuous flow coupled to a microscope-FTIR instrument. The detection and characterization of sugar samples were performed by recording their absorption spectrum in the wavelength range 700–1000 cm − 1 of the Mid-IR region. The proposed pseudo-continuous flow system is designed to improve the uniformity of the sample distribution in the analyzed area versus conventional systems. The obtained results for different sugars concentrations, show a very low measurement error of 4.35% in the absorption peak intensity, which is ten times lower than the error obtained using the conventional measurements.

Photoelectrocatalytic Properties of Porous TiO2 Films Prepared Using ODA as Template

2012 ◽  
Vol 457-458 ◽  
pp. 521-524 ◽  
Author(s):  
Wen Jie Zhang ◽  
Qian Li ◽  
Hong Bo He
Keyword(s):  
Reaction Time ◽  
Methyl Orange ◽  
Degradation Rate ◽  
Synergetic Effect ◽  
Degradation Process ◽  
Absorption Peak ◽  
Photocatalytic Process ◽  
Applied Potential ◽  
Peak Intensity ◽  
Photoelectrocatalytic Degradation

The functions of applied potential to the photoelectrocatalytic degradation process of methyl orange were investigated. When using 0.05 M NaCl and under different applied potentials, the degradation rate increased obviously with increasing applied potential. When the applied potential was between 0.6 V-1.0 V, the degradation rate was enhanced drastically. The detected current values got larger as the applied potential increased from 0 up to 1.2 V. There was no direct electro-degradation to the dye in the solution. The applied potential and the irradiated light had synergetic effect when they were applied to the solution at the same time. While after irradiation for 0 to 60 min, with the increasing reaction time, methyl orange absorption peak intensity shrank obviously. The azo and benzene groups in methyl orange degraded totally under photocatalytic process.

A New Modeling Approach to Estimate the Concentration of Tibolone in Acetone Solvent through Raman Spectra

2014 ◽  
Vol 881-883 ◽  
pp. 698-701
Author(s):  
Lei Lei Xiang ◽  
Zuo Liang Sha ◽  
Liang Zhu
Keyword(s):  
Particle Size ◽  
Particle Size Distribution ◽  
Raman Spectra ◽  
Temperature Characteristic ◽  
Characteristic Peak ◽  
Peak Intensity Ratio ◽  
Peak Intensity ◽  
Testing Data ◽  
The Mean ◽  
Estimated Error

Raman spectra are sensitive to solute, solid or polymorphs concentrations, particle size distribution and temperature. Characteristic peak positions of tibolone and acetone were observed at 1559cm-1 and 787cm-1. In this paper, we used the LabRAM HR800 System to detect the Raman spectra of 11 undersaturated standard solutions (concentration range 0-150 mg/ml) at 40°C; built model that estimating concentration of tibolone in acetone solvent by relating peak intensity ratio of the components to the concentration of the solution, and the mean estimated error was only 1.723% in the testing data. The results indicate that this method of estimating concentration is feasible and simple.

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