scholarly journals Fluorescent lamp tungsten filament thermionic emission gun as a novel humidity optical sensor

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Hossein Torabi-Monfared ◽  
Leila Sherafat ◽  
Mohammad Mahdi Doroodmand ◽  
Fazlolah Eshghi
Keyword(s):  
Optical Sensor ◽  
Detection System ◽  
Thermionic Emission ◽  
Fluorescent Lamp ◽  
Health Food ◽  
X Ray Diffraction ◽  
Tungsten Filament ◽  
X Ray ◽  
Relative Standard ◽  
Set Up

AbstractDetecting humidity have been remained a continuing concern within some important areas such as structural health, food processing, industrial as well as agricultural products. In this study, a novel humidity optical sensor is introduced based on the thermionic emission of tungsten filament using the fluorescent lamp set-up. Estimated blue compliant using a charged coupling device camera in optical image of the tungsten filament was confirmed as an appropriate detection system for relative humidity (RH) sensing. The fabricated optical sensor has wide linear range (2.0–98% RH), improved detection limit (< 5.0% RH), acceptable saturated limit (> 99.0% RH), improved percentage of relative standard deviation (4.18%, n = 2), adequate hysteresis (< 4.0% RH) and a shorter rise time (< 5.0 s), respectively. The mechanism behind this detection system is based on the interaction between H2O and tungsten filament during formation of W$${\mathrm{O}}_{3}$$ O 3 .x $${\mathrm{H}}_{2}$$ H 2 O (x = 1–2) in terms of some spectroscopic obtained evidences as well as Fourier transform infrared and X-ray diffraction spectrometries.

scholarly journals Fluorescent lamp tungsten filament thermionic emission gun as a novel humidity optical sensor

2021 ◽  
Author(s):  
Leila Sherafat ◽  
Hossein Torabi-Monfared ◽  
Mohammad Mahdi Doroodmand ◽  
Fazlolah Eshghi
Keyword(s):  
Optical Sensor ◽  
Food Processing ◽  
Detection System ◽  
Thermionic Emission ◽  
Fluorescent Lamp ◽  
Health Food ◽  
X Ray Diffraction ◽  
Tungsten Filament ◽  
X Ray ◽  
Relative Standard

Abstract Detecting humidity is a continuing concern within important area such as structural health, food processing, industrial as well agricultural products. In this study, a novel humidity optical sensor is introduced based on the thermionic emission of tungsten filament of a fluorescent lamp. Estimated blue compliant using a charged coupling device camera (CCD) in optical image of the tungsten filament is considered as appropriate detection system for relative humidity (RH) sensing. . The fabricated optical sensor has acceptable linear range (2.0- 98 % RH), improved detection limit (<5.0 % RH), acceptable saturated limit (> 99.0 % RH), improved percentage of relative standard deviation (4.18%, n=2), adequate hysteresis (<4.0 % RH) and a shorter rise time (<5.0 s), respectively. The mechanism behind this detection system was based on the interaction between H2O and tungsten filament during formation of WO3.x H2O (x = 1-2) based on the patented X-ray diffraction analysis.

Evaluation of Freezing Methods by Low Temperature X-Ray Diffraction

1977 ◽  
Vol 35 ◽  
pp. 330-333
Author(s):  
T. Gulik-Krzywicki ◽  
M.J. Costello
Keyword(s):  
Biological Materials ◽  
Molecular Organization ◽  
X Ray Diffraction ◽  
Glass Capillary ◽  
X Ray ◽  
Rate Dependent ◽  
Before And After ◽  
Freeze Etching ◽  
Diffraction Patterns ◽  
Set Up

Freeze-etching electron microscopy is currently one of the best methods for studying molecular organization of biological materials. Its application, however, is still limited by our imprecise knowledge about the perturbations of the original organization which may occur during quenching and fracturing of the samples and during the replication of fractured surfaces. Although it is well known that the preservation of the molecular organization of biological materials is critically dependent on the rate of freezing of the samples, little information is presently available concerning the nature and the extent of freezing-rate dependent perturbations of the original organizations. In order to obtain this information, we have developed a method based on the comparison of x-ray diffraction patterns of samples before and after freezing, prior to fracturing and replication.Our experimental set-up is shown in Fig. 1. The sample to be quenched is placed on its holder which is then mounted on a small metal holder (O) fixed on a glass capillary (p), whose position is controlled by a micromanipulator.

Rectifying Behavior of Aligned ZnO Nanorods on Mg0.3Zn0.7O Thin Film Template

2011 ◽  
Vol 364 ◽  
pp. 35-39 ◽  
Author(s):  
Salina Muhamad ◽  
Abu Bakar Suriani ◽  
Mohamad Hafiz Mamat ◽  
Rafidah Ahmad ◽  
Mohamad Rusop
Keyword(s):  
Thin Film ◽  
Zno Nanorods ◽  
Thermionic Emission ◽  
Deposition Method ◽  
X Ray Diffraction ◽  
X Ray ◽  
Hexagonal Shape ◽  
Semiconductor Junction ◽  
Vertically Aligned ◽  
Scanning Electron

Rectifying behavior more than 3 orders of aligned zinc oxide (ZnO) nanorods grown on Mg0.3Zn0.7O thin film template using chemical bath deposition method was observed, giving a barrier height of 0.75 eV, and the ideality factor achieved was almost 6, which was analyzed using thermionic emission theory. Field emission scanning electron microscope (FESEM) images revealed that the grown ZnO was in hexagonal shape, uniformly distributed and in vertically aligned form. The crystallinity of the sample being studied using X-ray diffraction (XRD), where the highest peak was found at (002) phase, confirming that high crytallinity of ZnO was attained. The effect of metal/semiconductor junction between metal and aligned ZnO nanorods was discussed in further details.

Large-scale and facile fabrication of PbSe nanostructures by selenization of a Pb sheet

2015 ◽  
Vol 08 (05) ◽  
pp. 1550063 ◽  
Author(s):  
Sara Hoomi ◽  
Ramin Yousefi ◽  
Farid Jamali-Sheini ◽  
Abdolhossein Sáaedi ◽  
Mohsen Cheraghizade ◽  
...  
Keyword(s):  
Large Scale ◽  
Chemical Vapor ◽  
Infrared Region ◽  
Photoelectron Spectra ◽  
X Ray Diffraction ◽  
X Ray ◽  
Facile Fabrication ◽  
Higher Temperature ◽  
Set Up ◽  
Lower Temperature

PbSe nanostructures were synthesized by selenization of lead sheets in a chemical vapor deposition (CVD) set-up under a selenium ambiance. The lead sheets were placed in the different temperature zones, between 300°C and 450°C. Field emission scanning electron microscope (FESEM) images showed that, PbSe nanostructures grown on the lead sheets with different morphologies. PbSe nanostructures with flakes shape were grown on the lead sheets that were placed in the lower temperature, while PbSe nanocubes and nanorods, which were grown on the nanocubes, were grown on the lead sheets in the higher temperature. The phase and composition of the product were identified by X-ray diffraction (XRD) pattern and X-ray photoelectron spectra (XPS). The XRD and XPS results showed that, the PbSe phase was started to form after 350°C and completed at 450°C. However, the XPS results showed that the Se concentration was different in the samples. In addition, Raman measurements confirmed the XRD and XPS results and indicated three Raman active modes, which belonged to PbSe phase for the nanostructures. The optical properties of the products were characterized by UV–Vis. The optical characterization results showed a band gap for the PbSe nanostructures in the infrared region.

An X-Ray Study of the Structure of the Alkaline Earth Oxide Cathode

1962 ◽  
Vol 6 ◽  
pp. 185-190
Author(s):  
Paul Lublin
Keyword(s):  
Diffraction Study ◽  
Alkaline Earth ◽  
Thermionic Emission ◽  
X Ray Diffraction ◽  
Emission Data ◽  
Alkaline Earth Oxide ◽  
X Ray ◽  
Oxide Cathode

AbstractArt X-ray diffraction study has been conducted on the emissive coating (Ba, Sr, CaO) of experimental diodes from which thermionic emission data were taken before X-ray analysis. The tubes were then opened and the oxide protected by special techniques in order to prevent the formation of the hydroxide. In addition to X-ray diffraction, other techniques were used to give a complete description of the structures present.

Synthesis and Structural Characterization of Ca14NbxIn1-xAs11 (x ≈ 0.85)

2016 ◽  
Vol 257 ◽  
pp. 147-151 ◽  
Author(s):  
Yi Wang ◽  
Svilen Bobev
Keyword(s):  
Physical Properties ◽  
Side Reaction ◽  
Structure Type ◽  
Major Product ◽  
X Ray Diffraction ◽  
X Ray ◽  
Ongoing Work ◽  
Set Up

Single-crystals of the new compound Ca14NbxIn1–xAs11 have been obtained from a solid-state reaction in a sealed Nb ampoule. The initial experiment had been set up with the aim to investigate the effect of electron doping (via In) on the crystal structure and physical properties of Ca14MnAs11. Subsequent single-crystal X-ray diffraction and elemental analysis work suggested that instead of Ca14MnxIn1–xAs11, the major product of the reaction is the phase Ca14NbxIn1–xAs11. This supposition was corroborated when the title compound was synthesized from a reaction of Ca, In and As in a sealed Nb ampoule, proving that, 1) Mn metal is not included in the structure, and 2) that the inadvertent side reaction of As with the walls of the Nb container is the source of the niobium. The overall structure is isotypic with the tetragonal Ca14AlSb11 structure type (space group I41/acd), although some marked differences between the two must be noted. Current ongoing work is focused on the synthesis of phase pure polycrystalline samples and determination of the physical properties of this unusual transition metal Zintl phase.

scholarly journals High-Throughput Crystallization Pipeline at the Crystallography Core Facility of the Institut Pasteur

Molecules ◽  
2019 ◽  
Vol 24 (24) ◽  
pp. 4451 ◽  
Author(s):  
Patrick Weber ◽  
Cédric Pissis ◽  
Rafael Navaza ◽  
Ariel E. Mechaly ◽  
Frederick Saul ◽  
...  
Keyword(s):  
High Throughput ◽  
Sequence Data ◽  
Data Bank ◽  
Whole Genome Sequence ◽  
Whole Genome ◽  
X Ray Diffraction ◽  
Sequencing Technology ◽  
X Ray ◽  
Set Up ◽  
General User

The availability of whole-genome sequence data, made possible by significant advances in DNA sequencing technology, led to the emergence of structural genomics projects in the late 1990s. These projects not only significantly increased the number of 3D structures deposited in the Protein Data Bank in the last two decades, but also influenced present crystallographic strategies by introducing automation and high-throughput approaches in the structure-determination pipeline. Today, dedicated crystallization facilities, many of which are open to the general user community, routinely set up and track thousands of crystallization screening trials per day. Here, we review the current methods for high-throughput crystallization and procedures to obtain crystals suitable for X-ray diffraction studies, and we describe the crystallization pipeline implemented in the medium-scale crystallography platform at the Institut Pasteur (Paris) as an example.

Shock Wave Compression of NaCl Single Crystals observed by Flash-X-Ray Diffraction

1978 ◽  
Vol 33 (8) ◽  
pp. 918-923 ◽  
Author(s):  
F. Müller ◽  
E. Schulte
Keyword(s):  
Shock Wave ◽  
Single Crystals ◽  
Observation Time ◽  
Plane Shock ◽  
X Ray Diffraction ◽  
X Ray ◽  
Wave Compression ◽  
Shock Wave Compression ◽  
Diffraction Patterns ◽  
Set Up

Flash-x-ray-diffraction patterns (FXD) with an exposure time of 4 ns of NaCl single crystals compressed by plane shock waves are obtained at pressures of about 30 kbar. From the diffraction patterns the compression is determined and compared with Hugoniot data. During shock load the lattice shows an uniaxial compression. While in case of measurements at the free surface an observation time of only a few nanoseconds is available, this experimental set-up allows an observation time of two microseconds.

A simple technique to control macromolecular crystal nucleation efficiently using a standard vapour-diffusion setup

2000 ◽  
Vol 33 (3) ◽  
pp. 988-989 ◽  
Author(s):  
Luca Jovine
Keyword(s):  
Data Collection ◽  
Diffraction Analysis ◽  
Vapour Pressure ◽  
Simple Technique ◽  
Crystal Nucleation ◽  
X Ray Diffraction ◽  
X Ray ◽  
Vapour Diffusion ◽  
Discrete Amount ◽  
Set Up

Excessive nucleation often leads to a large number of small macromolecular crystals that are not useful for X-ray diffraction analysis. Crystals with dimensions suitable for data collection can be reproducibly obtained by releasing, for a discrete amount of time, the vapour pressure in both hanging- and sitting-drop experiments, set up at lower precipitant concentrations than those required for crystallization.

Kinetics of high-pressure mineral phase transformations using in situ time-resolved X-ray diffraction in the Paris-Edinburgh cell: a practical guide for data acquisition and treatment

2008 ◽  
Vol 72 (2) ◽  
pp. 683-695 ◽  
Author(s):  
J. P. Perrillat
Keyword(s):  
High Pressure ◽  
Phase Transformations ◽  
Kinetic Studies ◽  
X Ray Diffraction ◽  
Time Resolved ◽  
X Ray ◽  
Practical Guide ◽  
Set Up ◽  
Isothermal Kinetic

AbstractSynchrotron X-ray diffraction (XRD) is a powerful technique to study in situ and in real-time the structural and kinetic processes of pressure-induced phase transformations. This paper presents the experimental set-up developed at beamline ID27 of the ESRF to perform time-resolved angle dispersive XRD in the Paris-Edinburgh cell. It provides a practical guide for the acquisition of isobaric-isothermal kinetic data and the construction of transformation-time plots. The interpretation of experimental data in terms of reaction mechanisms and transformation rates is supported by an overview of the kinetic theory of solid-solid transformations, with each step of data processing illustrated by experimental results of relevance to the geosciences. Reaction kinetics may be affected by several factors such as the sample microstructure, impurities or differential stress. Further high-pressure kinetic studies should investigate the influence of such processes, in order to acquire kinetic information more akin to natural or technological processes.

Sign in / Sign up

Export Citation Format

Share Document