Porous silver-TiO2 Schottky-type chemical sensor fabricated on thermally oxidised titanium

2008 ◽  
Vol 44 (2) ◽  
pp. 161 ◽  
Author(s):  
F. Hossein-Babaei
Keyword(s):  
Chemical Sensor ◽  
Schottky Type ◽  
Porous Silver

Ultrahigh-Vacuum Electron Microscopy for Gold Nanostructures

2001 ◽  
Vol 7 (S2) ◽  
pp. 920-921
Author(s):  
Yukihito Kondo ◽  
Kimiharu Okamoto ◽  
Mikio Naruse ◽  
Toshikazu Honda ◽  
Mike Kersker
Keyword(s):  
Electron Microscopy ◽  
Field Emission ◽  
Electronic Devices ◽  
Ultrahigh Vacuum ◽  
Gold Nanostructures ◽  
Scanning Tunneling ◽  
Nano Scale ◽  
Transmission Electron ◽  
Column Type ◽  
Schottky Type

Ultrahigh-vacuum transmission electron microscopy (UHVTEM) has become increasingly popular for the direct observation of nanostructures having clean surfaces, since industrial requirements to make and research nano-scale materials have been rapidly growing for quantum or nanoscale electronic devices. Since we have first developed high resolution UHVTEM in 1986, the UHVTEMs have been evolved with steady advances such as UHV compatible goniometer, field emission gun or etc. Furthermore, the UHVTEM started to combine analytical capabilities such as energy dispersive X-ray spectrometer, in-column type energy filter and etc., and to combine STM (scanning tunneling microscope). The UHV technology is essential for the analysis, because the portion of contaminant in a nano-scale specimen increases as the size of the specimen goes down. This paper reports the results of gold nanostructures by recently the developed UHVTEM.Figure 1 shows recently developed UHVTEM with Schottky type field emission gun.

scholarly journals Highly-Efficient Sulfonated UiO-66(Zr) Optical Fiber for Rapid Detection of Trace Levels of Pb2+

2021 ◽  
Vol 22 (11) ◽  
pp. 6053
Author(s):  
Marziyeh Nazari ◽  
Abbas Amini ◽  
Nathan T. Eden ◽  
Mikel C. Duke ◽  
Chun Cheng ◽  
...  
Keyword(s):  
Optical Fiber ◽  
Rapid Detection ◽  
Chemical Sensor ◽  
Metal Organic Framework ◽  
Aqueous System ◽  
Icp Oes ◽  
Efficient Detection ◽  
Low Concentrations ◽  
Fabry Perot ◽  
Metal Organic

Lead detection for biological environments, aqueous resources, and medicinal compounds, rely mainly on either utilizing bulky lab equipment such as ICP-OES or ready-made sensors, which are based on colorimetry with some limitations including selectivity and low interference. Remote, rapid and efficient detection of heavy metals in aqueous solutions at ppm and sub-ppm levels have faced significant challenges that requires novel compounds with such ability. Here, a UiO-66(Zr) metal-organic framework (MOF) functionalized with SO3H group (SO3H-UiO-66(Zr)) is deposited on the end-face of an optical fiber to detect lead cations (Pb2+) in water at 25.2, 43.5 and 64.0 ppm levels. The SO3H-UiO-66(Zr) system provides a Fabry–Perot sensor by which the lead ions are detected rapidly (milliseconds) at 25.2 ppm aqueous solution reflecting in the wavelength shifts in interference spectrum. The proposed removal mechanism is based on the adsorption of [Pb(OH2)6]2+ in water on SO3H-UiO-66(Zr) due to a strong affinity between functionalized MOF and lead. This is the first work that advances a multi-purpose optical fiber-coated functional MOF as an on-site remote chemical sensor for rapid detection of lead cations at extremely low concentrations in an aqueous system.

scholarly journals Optoelectronic properties of highly porous silver oxide thin film

2021 ◽  
Vol 3 (1) ◽  
Author(s):  
Ahmad Al-Sarraj ◽  
Khaled M. Saoud ◽  
Abdelaziz Elmel ◽  
Said Mansour ◽  
Yousef Haik
Keyword(s):  
Thin Film ◽  
Thin Films ◽  
Electron Microscope ◽  
Plasma Etching ◽  
Silver Oxide ◽  
Oxidation Time ◽  
Oxide Thin Film ◽  
X Ray ◽  
Porous Silver ◽  
Highly Porous

Abstract In this paper, we report oxidation time effect on highly porous silver oxide nanowires thin films fabricated using ultrasonic spray pyrolysis and oxygen plasma etching method. The NW’s morphological, electrical, and optical properties were investigated under different plasma etching periods and the number of deposition cycles. The increase of plasma etching and oxidation time increases the surface roughness of the Ag NWs until it fused to form a porous thin film of silver oxide. AgNWs based thin films were characterized using X-ray diffraction, scanning electron microscope, transmission electron microscope, X-ray photoemission spectroscopy, and UV–Vis spectroscopy techniques. The obtained results indicate the formation of mixed mesoporous Ag2O and AgO NW thin films. The Ag2O phase of silver oxide appears after 300 s of oxidation under the same conditions, while the optical transparency of the thin film decreases as plasma etching time increases. The sheet resistance of the final film is influenced by the oxidation time and the plasma application periodicity. Graphic abstract

scholarly journals Identification and Quantification of Olive Oil Quality Parameters Using an Electronic Nose

Agriculture ◽  
2021 ◽  
Vol 11 (7) ◽  
pp. 674
Author(s):  
Nawaf Abu-Khalaf
Keyword(s):  
Olive Oil ◽  
Electronic Nose ◽  
Chemical Sensor ◽  
Chemical Constituents ◽  
Oil Quality ◽  
Quality Parameters ◽  
Signal Acquisition ◽  
Good Precision ◽  
Olive Oil Quality ◽  
Quality Categories

An electronic nose (EN), which is a kind of chemical sensor, was employed to check olive oil quality parameters. Fifty samples of olive oil, covering the four quality categories extra virgin, virgin, ordinary virgin and lampante, were gathered from different Palestinian cities. The samples were analysed chemically using routine tests and signals for each chemical were obtained using EN. Each signal acquisition represents the concentration of certain chemical constituents. Partial least squares (PLS) models were used to analyse both chemical and EN data. The results demonstrate that the EN was capable of modelling the acidity parameter with a good performance. The correlation coefficients of the PLS-1 model for acidity were 0.87 and 0.88 for calibration and validation sets, respectively. Furthermore, the values of the standard error of performance to standard deviation (RPD) for acidity were 2.61 and 2.68 for the calibration and the validation sets, respectively. It was found that two principal components (PCs) in the PLS-1 scores plot model explained 86% and 5% of EN and acidity variance, respectively. PLS-1 scores plot showed a high performance in classifying olive oil samples according to quality categories. The results demonstrated that EN can predict/model acidity with good precision. Additionally, EN was able to discriminate between diverse olive oil quality categories.

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