Experimental Techniques
Xianshuang Wang; Ruibin Liu
Abstract
The determination of detonation performance and sensitivity is an important research content of explosive testing technology. However, the traditional test method usually requires a large amount of samples due to the limitation of the critical diameter and other detonation conditions. Therefore, it will ...
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The determination of detonation performance and sensitivity is an important research content of explosive testing technology. However, the traditional test method usually requires a large amount of samples due to the limitation of the critical diameter and other detonation conditions. Therefore, it will inevitably bring great test risk, high test cost and measurement uncertainty. In this case, it is urgent to develop new testing technology with small dosage and high precision. Recently, a micro-zone explosive simulator for the characterization of explosives is proposed by Wang and Liu et.al. According to their work, laser-induced micro-explosion is produced by micrograms of explosives irritated by pulsed laser, has been proved to be closely related to macroscopic detonation. Therefore, it can be used as a micro-zone explosive simulator for the characterization of explosives. The aim of this letter is to shed new light on the determination of detonation performance and sensitivity and highlighted the importance of close integration of experimental, statistical, and theoretical efforts.
S. Kotresh; Y. T. Ravikiran; S.C. Vijaya Kumari; H.G. Raj Prakash; S. Thomas
Abstract
In this present work, Polyaniline (PANI) and Polyaniline-Niobium Pentoxide (PANI-Nb2O5) composite were synthesized separately at room temperature by chemical polymerization of aniline without/with Nb2O5. Comparative study of XRD pattern of PANI and the composite confirms superficial deposition of PANI ...
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In this present work, Polyaniline (PANI) and Polyaniline-Niobium Pentoxide (PANI-Nb2O5) composite were synthesized separately at room temperature by chemical polymerization of aniline without/with Nb2O5. Comparative study of XRD pattern of PANI and the composite confirms superficial deposition of PANI on Nb2O5 and the average size of the composite particle was found to be 10 nm. Aggregated granular morphology of the composite as compared to pristine PANI was confirmed by SEM images. Sensitivity of PANI-Nb2O5 composite to humidity at room temperature was tested using digital LCR meter at a selected frequency of 100 Hz and the results showed consistent variation in impedance from 60 KΩ to 360 KΩ within the relative humidity (RH) range 25% - 95%. Further, the response and recovery time of the composite were measured to be 80s and 90s respectively and the composite showed stable sensing ability over a period of one month.
A. B. Gadkari; T.J. Shinde; P.N. Vasambekar
Abstract
The Mg0.6Cd0.4Fe2O4 ferrite powder was synthesized by oxalate co-precipitation method. The crystal structure and surface morphology were examined by XRD, SEM and FT-IR techniques. The nanocrystallite Mg0.6Cd0.4Fe2O4 sensor was tested for LPG, Cl2 and C2H5OH. The sensitivity was measured at various operating ...
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The Mg0.6Cd0.4Fe2O4 ferrite powder was synthesized by oxalate co-precipitation method. The crystal structure and surface morphology were examined by XRD, SEM and FT-IR techniques. The nanocrystallite Mg0.6Cd0.4Fe2O4 sensor was tested for LPG, Cl2 and C2H5OH. The sensitivity was measured at various operating temperatures in the range of 100-400 o C. The sensor shows highest sensitivity at operating temperature 225 o C for LPG (~ 78%). It shows good sensitivity at operating temperature of 198 o C for Cl2 (~75%) and ethanol (~ 65%). The sensor exhibits a lower response and recovery time for LPG and Cl2 as compared to C2H5OH.
Richa Srivastava;B. C. Yadav
Abstract
Present paper deals with a comparative performance of n-type ZnO, ZnO-TiO2 and ZnO-Nb2O5 nanomaterials as humidity sensors. ZnO was synthesized through hydroxide route. TiO2 and then Nb2O5 were used as additives for improvement of sensitivity. Scanning electron micrograph of ZnO shows rod-like particles ...
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Present paper deals with a comparative performance of n-type ZnO, ZnO-TiO2 and ZnO-Nb2O5 nanomaterials as humidity sensors. ZnO was synthesized through hydroxide route. TiO2 and then Nb2O5 were used as additives for improvement of sensitivity. Scanning electron micrograph of ZnO shows rod-like particles with average diameter 40 nm. Structural properties by X-Ray diffraction were studied. The minimum crystallite sizes of ZnO-TiO2 and ZnO-Nb2O5 calculated from Scherrer’s formula were found to be 19 and 17 nm respectively. The pellet of each sensing material was annealed at temperatures 150, 300, 450 and 550 ?C for 3 h and checked for its sensing efficiency. Each heat treated pellet was exposed to humidity under controlled condition and variations in resistance with the humidity were recorded. Comparative study of sensitivities of each sensing element was performed. Average sensitivity achieved was 8 MΩ/%RH for the n-type ZnO annealed at 550 ?C. After chemical mixing of TiO2, the sensitivity increased to 18 MΩ/%RH and after Nb2O5, it was found to be 19 MΩ/%RH. Activation energy of electrical transport and Kelvin radii of each sensing elements were also studied.