202 research outputs found
Qualification Testing, Evaluation and Test Methods of Gas Generator for IEDs Applications
In this work, the design qualification testing, evaluation and test methods of gas generator using double base (DB) propellant having square flake shape is explained for an improvised explosive devices (IEDs) applications. Various kinds of the gas generators are used to save life of an aeronaut in the fastest way from the disable fighter aircraft. Due to their ruggedised design, compactness, safe transportation, repeatability in performance and quick operation, the gas generator are used. The gas generator is designed and developed keeping functional, mechanical and structural requirements in mind. The gas generators are subjected to the various qualification tests, electrical characterisation followed by closed vessel (CV) firings at hot and cold temperatures. The gas generators after the successful qualification tests are validated through the ground trials i.e. dynamic firing of disruptor during the development phase. The damage caused due to impact of the projectile is assessed in terms of crater as acceptance criteria at stand-off distance of 0.5 m and 1m. The gas generator discussed in this research article is used to disrupt the suspected IEDs by creating a high-speed jet using water-jet disruptor. In conclusion, after successful qualification testing, the gas generator for IEDs application meets all the specifications as per userâs requirements
The study of Microstructure of III-V Polar on Non-Polar Heterostructures By HRXRD
In this article, we report on the detailed high resolution x-ray diffraction data analysis of three GaAs films deposited by metal organic vapour phase epitaxy on Si substrates. In the GaAs/Si films the effect of anti phase domains is seen by the selective broadening of (002) and (006) reflections. Further as the (006) reflection is a very weak reflection, such films cannot be analyzed by conventional Williamson-Hall plots using (002), (004) and (006) reflections. We find that using (111), (333) and (444) reflections it is possible to use the standard Williamson-Hall analysis and extract parameters related to the microstructure of the films. We have also carried out the analysis to determine the tilt and twist between the mosaic blocks after correcting for the effects of the finite lateral coherence length.
When you are citing the document, use the following link http://essuir.sumdu.edu.ua/handle/123456789/930
The study of Microstructure of III-V Polar on Non-Polar Heterostructures By HRXRD
In this article, we report on the detailed high resolution x-ray diffraction data analysis of three GaAs films deposited by metal organic vapour phase epitaxy on Si substrates. In the GaAs/Si films the effect of anti phase domains is seen by the selective broadening of (002) and (006) reflections. Further as the (006) reflection is a very weak reflection, such films cannot be analyzed by conventional Williamson-Hall plots using (002), (004) and (006) reflections. We find that using (111), (333) and (444) reflections it is possible to use the standard Williamson-Hall analysis and extract parameters related to the microstructure of the films. We have also carried out the analysis to determine the tilt and twist between the mosaic blocks after correcting for the effects of the finite lateral coherence length.
When you are citing the document, use the following link http://essuir.sumdu.edu.ua/handle/123456789/930
Evaluation of Vertical Coherence Length, Twist and Microstrain of GaAs / Si Epilayers Using Modified Williamson-Hall Analysis
Modified Williamson-Hall (WH) analysis is used to determine the reliable values of the microstructures for
Zincblende epilayers grown on non-polar substrates. Systematic high resolution X-ray diffraction (HRXRD) experiments
are performed for several skew symmetric reflections which enable an accurate measurement of the
values of vertical coherence length (VCL) and microstrain of GaAs epilayers grown on Si. Furthermore, a simple
method based on the orientation of Burgers vector is proposed for estimating the ratio of tilt and twist. In this
method, the twist can be found easily once tilt is known. It is rather quick and the measured values of twist are
very similar to those which are otherwise estimated by acquiring numerous HRXRD scans along with tedious
fitting procedures. Presence of 60 mixed dislocations is confirmed from the cross sectional high resolution
transmission electron microscope images of GaAs / Si samples. Furthermore, the estimated value of VCL is
equivalent to the layer thickness measured by the surface profiler.
When you are citing the document, use the following link http://essuir.sumdu.edu.ua/handle/123456789/3598
The Impact of Perceived Expectations and Uncertainty on Firm Investment
This paper analyses the (differential) impact of perceived expectations and uncertainty on investment spending in small and large firms. We analyse two types of investment, viz. aggregate investment and investment in energy-saving technologies, using Dutch firm level data. The results show that expectations and uncertainty about input- and output prices and domestic demand have substantial but different effects on investment spending in firms of different sizes. Furthermore, we find evidence, at least for small firms, that there are important differences between the effects of uncertainty about input and output variable
Author Correction: A chickpea genetic variation map based on the sequencing of 3,366 genomes
In Extended Data Fig. 1 of this Article, the labels âMarket classâ and âBiological statusâ were inadvertently swapped. In the corresponding figure legend, âTrack 1: Biological status; Track 2: Market class;â should have been âTrack 1: Market class; Track 2: Biological status;â. The original Article has been corrected online
Energy dependence of Ï meson production at forward rapidity in pp collisions at the LHC
The production of mesons has been studied in pp collisions at LHC energies with the ALICE detector via the dimuon decay channel in the rapidity region . Measurements of the differential cross section are presented as a function of the transverse momentum () at the center-of-mass energies , 8 and 13 TeV and compared with the ALICE results at midrapidity. The differential cross sections at and 13 TeV are also studied in several rapidity intervals as a function of , and as a function of rapidity in three intervals. A hardening of the -differential cross section with the collision energy is observed, while, for a given energy, spectra soften with increasing rapidity and, conversely, rapidity distributions get slightly narrower at increasing . The new results, complementing the published measurements at and 7 TeV, allow one to establish the energy dependence of meson production and to compare the measured cross sections with phenomenological models. None of the considered models manages to describe the evolution of the cross section with and rapidity at all the energies.publishedVersio
Ï production in pâPb collisions at âsNN=8.16 TeV
Ï production in pâPb interactions is studied at the centre-of-mass energy per nucleonânucleon collision âsNN = 8.16 TeV with the ALICE detector at the CERN LHC. The measurement is performed reconstructing bottomonium resonances via their dimuon decay channel, in the centre-of-mass rapidity intervals 2.03 < ycms < 3.53 and â4.46 < ycms < â2.96, down to zero transverse momentum. In this work, results on the Ï(1S) production cross section as a function of rapidity and transverse momentum are presented. The corresponding nuclear modification factor shows a suppression of the Ï(1S) yields with respect to pp collisions, both at forward and backward rapidity. This suppression is stronger in the low transverse momentum region and shows no significant dependence on the centrality of the interactions. Furthermore, the Ï(2S) nuclear modification factor is evaluated, suggesting a suppression similar to that of the Ï(1S). A first measurement of the Ï(3S) has also been performed. Finally, results are compared with previous ALICE measurements in pâPb collisions at âsNN = 5.02 TeV and with theoretical calculations.publishedVersio
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