Characterization of thermal imagers under various ambient conditions

2009 ◽  
Author(s):  
Riho Vendt ◽  
Priit Jaanson ◽  
Viktor Vabson ◽  
Martin Vilbaste ◽  
Toomas Kübarsepp ◽  
...  
Keyword(s):  
Ambient Conditions ◽  
Thermal Imagers

scholarly journals Characterization of interferences to in situ observations of <i>δ</i><sup>13</sup>CH<sub>4</sub> and C<sub>2</sub>H<sub>6</sub> when using a cavity ring-down spectrometer at industrial sites

2017 ◽  
Vol 10 (6) ◽  
pp. 2077-2091 ◽  
Author(s):  
Sabina Assan ◽  
Alexia Baudic ◽  
Ali Guemri ◽  
Philippe Ciais ◽  
Valerie Gros ◽  
...  
Keyword(s):  
Near Infrared ◽  
Field Tests ◽  
Isotopic Signature ◽  
Ambient Conditions ◽  
Industrial Sites ◽  
Source Determination ◽  
Infrared Spectral ◽  
The Subject

Abstract. Due to increased demand for an understanding of CH4 emissions from industrial sites, the subject of cross sensitivities caused by absorption from multiple gases on δ13CH4 and C2H6 measured in the near-infrared spectral domain using CRDS has become increasingly important. Extensive laboratory tests are presented here, which characterize these cross sensitivities and propose corrections for the biases they induce. We found methane isotopic measurements to be subject to interference from elevated C2H6 concentrations resulting in heavier δ13CH4 by +23.5 ‰ per ppm C2H6 ∕ ppm CH4. Measured C2H6 is subject to absorption interference from a number of other trace gases, predominantly H2O (with an average linear sensitivity of 0.9 ppm C2H6 per  % H2O in ambient conditions). Yet, this sensitivity was found to be discontinuous with a strong hysteresis effect and we suggest removing H2O from gas samples prior to analysis. The C2H6 calibration factor was calculated using a GC and measured as 0.5 (confirmed up to 5 ppm C2H6). Field tests at a natural gas compressor station demonstrated that the presence of C2H6 in gas emissions at an average level of 0.3 ppm shifted the isotopic signature by 2.5 ‰, whilst after calibration we find that the average C2H6 : CH4 ratio shifts by +0.06. These results indicate that, when using such a CRDS instrument in conditions of elevated C2H6 for CH4 source determination, it is imperative to account for the biases discussed within this study.

Preparation and Characterization of Carbon Xerogel Based Composites for Electrochemical Sensing and Photocatalytic Degradation

2021 ◽  
Vol 21 (4) ◽  
pp. 2323-2333
Author(s):  
Carmen I. Fort ◽  
Mihai M. Rusu ◽  
Lucian C. Pop ◽  
Liviu C. Cotet ◽  
Adriana Vulpoi ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Photocatalytic Degradation ◽  
Electrochemical Sensors ◽  
Sol Gel ◽  
Nanocomposite Material ◽  
Electrochemical Sensing ◽  
Ambient Conditions ◽  
Carbon Xerogel ◽  
Voltammetric Detection

In order to obtain a multifunctional nanocomposite material-for electrochemical sensors and photocatalytic applications, structures based on Bi, Fe and TiO2 were grown inside carbon xerogel supports (BiFeCX and BiFeCX-TiO2). First, a wet polymer containing Bi and Fe salts was obtained by following a modified resorcinol-formaldehyde based sol–gel route, followed by drying in ambient conditions, and pyrolysis under inert atmosphere. Then, through TiCl4 hydrolysis, TiO2 nanoparticles were deposited on the BiFeCX xerogel leading to BiFeCX-TiO2. The morphological and structural characterization of the investigated nanocomposites consisted in X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), Raman spectroscopy and N2 adsorption measurements, revealing porous carbon structures with embedded nanoparticles and the particularities driven by the pyrolysis and TiCl4 treatment. The new modified electrodes based on BiFeCX or BiFeCX-TiO2 nanocomposite materials, kept in a chitosan matrix (Chi) and deposited on a glassy carbon (GC) electrode surface (GC/Chi-BiFeCX or GC/Chi-BiFeCX-TiO2), were obtained and investigated for Pb(II) voltammetric detection and H2O2 amperometric detection. Moreover, the BiFeCX-TiO2 nanocomposite was tested for the photocatalytic degradation of methyl orange. The great potential of BiFeCX nanocomposite material for developing electrochemical sensors, or BiFeCX-TiO2 for sensors application and photocatalytic application was demonstrated.

scholarly journals Material Characterization of Magnetorheological Elastomers with Corroded Carbonyl Iron Particles: Morphological Images and Field-dependent Viscoelastic Properties

2019 ◽  
Vol 20 (13) ◽  
pp. 3311 ◽  
Author(s):  
Siti Aishah Binti Abdul Aziz ◽  
Saiful Amri Mazlan ◽  
Nur Azmah Nordin ◽  
Nor Azlin Nazira Abd Rahman ◽  
U Ubaidillah ◽  
...  
Keyword(s):  
Carbonyl Iron ◽  
Matrix Material ◽  
Rheological Characteristics ◽  
Iron Particles ◽  
Ambient Conditions ◽  
X Ray ◽  
Field Dependent ◽  
Mr Effect

High temperatures and humidity could alter the field-dependent rheological properties of MR materials. These environmental phenomena may accelerate the deterioration processes that will affect the long-term rheological reliability of MR materials such as MR elastomer (MRE). This study therefore attempts to investigate the field-dependent rheological characteristics of MRE with corroded carbonyl iron particles (CIPs). The corroded CIPs were treated with hydrochloric acid (HCl) as a way of providing realistic environments in gauging the CIPs reaction towards the ambient conditions. The corroded CIPs along with silicone rubber as a matrix material were used in the fabrication of the MRE samples. To observe the effect of HCl treatment on the CIPs, the morphological observations of MREs with non-corroded and corroded CIPs were investigated via field emission scanning electron microscopy (FESEM), energy-dispersive x-ray spectroscopy (EDX) and x-ray diffractometer (XRD). In addition, the magnetic properties were examined through the vibrating sample magnetometer (VSM), while the field-dependent rheological characteristics such as the storage modulus of MRE with the corroded CIPs were also tested and compared with the non-corroded CIPs. The results showed that the corroded CIPs possessed hydrangea-like structures. In the meantime, it was identified that a sudden reduction of up to 114% of the field-dependent MR effect of MRE with the corroded CIPs was observed as a result of the weakened interfacial bonding between the CIPs and the silicon in the outer layers of the CIPs structure.

Preparation and Characterization of Metal Sulfides in Ethylenediamine under Ambient Conditions through a γ-Irradiation Route

2001 ◽  
Vol 237 (1) ◽  
pp. 47-53 ◽  
Author(s):  
Meng Chen ◽  
Yi Xie ◽  
Haoyu Chen ◽  
Zhengping Qiao ◽  
Yitai Qian
Keyword(s):  
Metal Sulfides ◽  
Ambient Conditions ◽  
Γ Irradiation

Characterization of Plasma-Modified Fluoropolymer Surfaces Using Steady-State and Time-Resolved Fluorescence Spectroscopy

1994 ◽  
Vol 48 (5) ◽  
pp. 630-637 ◽  
Author(s):  
Ming Li ◽  
Michaeleen L. Pacholski ◽  
Frank V. Bright
Keyword(s):  
Steady State ◽  
Fluorescence Spectroscopy ◽  
Sulfonyl Chloride ◽  
Sodium Dodecylsulfate ◽  
Covalent Immobilization ◽  
Ambient Conditions ◽  
Time Resolved Fluorescence ◽  
Decay Kinetics ◽  
Time Resolved

Poly(hexafluoropropylene-co-tetrafluoroethylene) (FEP) has been widely used in biotechnology because of its unique surface properties and biocompatibility. Recent work from our group has shown that plasma discharge-modified FEP can be used as the substratum for development of a very stable immunosensor. This result has prompted us to study further this new surface under ambient conditions. In this paper, we report on the covalent immobilization of a pyrene residue (-Py) onto FEP-APS (FEP-aminopropyl silane) surfaces and the characterization of FEP-APS-Py using steady-state and time-resolved fluorescence spectroscopy. Among the immobilization schemes tested, we found that the covalent coupling of pyrene-sulfonyl chloride to FEP-APS is the easiest and yields the most photostable FEP-APS-Py derivative. Steady-state emission spectra of FEP-APS-Py in contact with H2O, β-cyclodextrin (β-CD), and sodium dodecylsulfate (SDS) aqueous solutions differ considerably from those of Py-SO3 in solution. Time-resolved fluorescence spectroscopy of FEP-APS-Py demonstrates that the decay kinetics are strongly affected by the presence of ionic quenchers and molecular oxygen, as well as β-CD and SDS. The results are consistent with the suggestion that the APS-Py moiety undergoes a slow time-dependent reconfiguration at the FEP/APS interface.

scholarly journals Infrared Radiation Assisted Stokes’ Law Based Synthesis and Optical Characterization of ZnS Nanoparticles

2016 ◽  
Vol 2016 ◽  
pp. 1-6 ◽  
Author(s):  
Beer Pal Singh ◽  
Ravish Kumar Upadhyay ◽  
Rakesh Kumar ◽  
Kamna Yadav ◽  
Hector I. Areizaga-Martinez
Keyword(s):  
Infrared Radiation ◽  
Zinc Nitrate ◽  
Ambient Conditions ◽  
X Ray Diffraction ◽  
Zns Nanoparticles ◽  
Ir Radiation ◽  
Phase Crystal ◽  
Free Body ◽  
Quiescent Fluid

The strategy and technique exploited in the synthesis of nanostructure materials have an explicit effect on the nucleation, growth, and properties of product materials. Nanoparticles of zinc sulfide (ZnS) have been synthesized by new infrared radiation (IR) assisted and Stokes’ law based controlled bottom-up approach without using any capping agent and stirring. IR has been used for heating the reaction surface designed in accordance with the well-known Stokes law for a free body falling in a quiescent fluid for the synthesis of ZnS nanoparticles. The desired concentration of aqueous solutions of zinc nitrate (Zn(NO3)2·4H2O) and thioacetamide (CH3CSNH2) was reacted in a controlled manner by IR radiation heating at the reaction area (top layer of reactants solution) of the solution which results in the formation of ZnS nanoparticles at ambient conditions following Stokes’ law for a free body falling in a quiescent fluid. The phase, crystal structure, and particle size of as-synthesized nanoparticles were studied by X-ray diffraction (XRD). The optical properties of as-synthesized ZnS nanoparticles were studied by means of optical absorption spectroscopic measurements. The optical energy band gap and the nature of transition have been studied using the well-known Tauc relation with the help of absorption spectra of as-synthesized ZnS nanoparticles.

Structural characterization of a new high-pressure phase of GaAsO4

2006 ◽  
Vol 62 (6) ◽  
pp. 1019-1024 ◽  
Author(s):  
David Santamaría-Pérez ◽  
Julien Haines ◽  
Ulises Amador ◽  
Emilio Morán ◽  
Angel Vegas
Keyword(s):  
Crystal Structure ◽  
High Pressure ◽  
High Pressures ◽  
Ambient Conditions ◽  
Hexagonal Cell ◽  
Octahedral Sites ◽  
New Phase ◽  
Pressure Phase

As in SiO2 which, at high pressures, undergoes the α-quartz → stishovite transition, GaAsO4 transforms into a dirutile structure at 9 GPa and 1173 K. In 2002, a new GaAsO4 polymorph was found by quenching the compound from 6 GPa and 1273 K to ambient conditions. The powder diagram was indexed on the basis of a hexagonal cell (a = 8.2033, c = 4.3941 Å, V = 256.08 Å3), but the structure did not correspond to any known structure of other AXO4 compounds. We report here the ab initio crystal structure determination of this hexagonal polymorph from powder data. The new phase is isostructural to β-MnSb2O6 and it can be described as a lacunary derivative of NiAs with half the octahedral sites being vacant, but it also contains fragments of the rutile-like structure.

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