Two standoff detection systems were assembled using an infrared telescope coupled to a Fourier transform spectrometer, cryocooled mercury-cadmium telluride detector, and telescope-coupled midinfrared excitation source. Samples of the highly energetic materials (HEMs) 2,4,6-trinitrotoluene (TNT) pentaerythritol tetranitrate (PETN) deposited on aluminum plates detected at several source-target distances by carrying out remote spectroscopy (RIRS) measurements substrates in active mode. The...

Measurements of ultrafast light scattering within a hemisphere are performed for statistical analysis nonequilibrium processes in VO2 epitaxial film. A Gerchberg-Saxton error reduction algorithm is applied accurate calculation surface autocorrelation function from data and partial reconstruction power spectral density function. Upon photoinduced phase transition VO2, the elastic reveals anisotropic grain-size-dependent dynamics. It was found that rate depends on optical absorption...

A tunable quantum cascade laser (QCL) spectrometer was used to develop methods for detecting and quantifying high explosives (HE) in soil based on multivariate analysis (MVA) artificial intelligence (AI). For quantification, mixes of 2,4-dinitrotoluene (DNT) concentrations from 0% 20% w/w with samples were investigated. Three types soils, bentonite, synthetic soil, natural used. partial least squares (PLS) regression model generated predicting DNT concentrations. To increase the selectivity,...

Mid-infrared (MIR) laser spectroscopy was used to detect the presence of residues high explosives (HEs) on fabrics. The discrimination vibrational signals HEs from a highly MIR-absorbing substrate achieved by simple and fast spectral evaluation without preparation standards using classical least squares (CLS) algorithm. Classical focuses minimizing differences between features actual spectra acquired MIR calculated modeled linear combinations neat components: HEs, fabrics, bias. Samples in...

Experimental observation of metal-insulator transition in epitaxial films vanadium dioxide is reported. Hemispherical angle-resolved light scattering technique applied for statistical analysis the phase processes on mesoscale. It shown that thermal hysteresis strongly depends spatial frequency surface irregularities. The transformation indicatrix sample morphology and principally different thin with higher internal elastic strain thicker where this suppressed by introduction misfit...

The growth-controlled synthesis of zinc oxide nanorods (ZnO NR) in the aqueous phase has been investigated. rods were grown on ZnO films previously deposited onto Si(100) and indium tin (ITO) substrates by RF magnetron sputtering. formation took place presence hexamethylenetetramine (HMT) as habit-control reagent. grains base film acted seeds that promoted longitudinal growth oxide. As-synthesized characterized X-ray diffraction, scanning electron microscopy (SEM), field emission SEM,...

Active mode standoff measurement using infrared spectroscopy were carried out in which the angle between target and source was varied from 0-70° with respect to surface normal of substrates containing traces highly energetic materials (explosives). The experiments made three sources: a modulated (Mod-FTIR), an unmodulated (UnMod-FTIR) scanning quantum cascade laser (QCL), part dispersive mid (MIR) spectrometer. targets consisted PENT 200 μg/cm² deposited on aluminum plates...

A tunable quantum cascade laser (QCL) spectrometer was used to develop methods for detecting and quantifying high explosives (HE) in soil based on multivariate analysis (MVA) artificial intelligence (AI). For quantification, mixes of 2,4-dinitrotoluene (2,4-DNT) with concentrations from 0% 20% w/w were investigated using three types soils: bentonite, synthetic soil, natural soil. Partial least squares regression model generated predicting 2,4-DNT concentrations. To increase its selectivity,...

A standoff multivariate calibration for detection of highly energetic materials (HEM) using Fourier transform infrared spectroscopy is presented in this report. The procedure consists sensing at 1 m distance and the variation three parameters detection. first variable considered was angular dependence: 0° to 45‡ from source-target with respect alignment target-detector. second consisted on use several surfaces which material deposited. substrates used were polished aluminum...

The optical properties for crystalline films of the highly energetic material (HEM) hexahydro-1,3,5-trinitro-s-triazine, which is also known as RDX, deposited on gold (Au) and stainless steel (SS) substrates are presented. RDX has two important stable conformational polymorphs at room temperature: α-RDX β-RDX. obtained in present work correspond to thin film samples predominantly β-RDX polymorph. infrared spectroscopic intensities measured showed significant differences with respect...

Abstract 1,3,5‐trinitroso‐1,3,5‐triazine (R‐Salt) is an insensitive energetic that has previously been used as improvised explosive. The work presented here a comprehensive study on the thermal properties and chemical characterization of R‐Salt. Thermal analysis was performed via differential scanning calorimetry (DSC) thermogravimetric (TGA) which found both crude recrystallized R‐Salt have similar but selected lid impacted profile onset temperature. Chemical Raman, Fourier‐transform...

Silver, gold, copper and platinum nanoparticles (NPs) were grown on surfaces in the form of patterns by exposure laser radiation onto droplets metal ion solutions aid a reducing agent. The generation from metallic NPs was achieved combining induced growth nanostructures incidence directly optical image formation techniques for transferring patterns. Near-UV (363.8 nm) visible (532 wavelengths used laser-induced into microstructures glass, quartz, stainless steel, silicon, gold-on-silicon...

Dielectric measurements of plastic explosives using a loaded waveguide technique via vector network analyzer and banded MMW extender modules operating at V-band (50 – 75 GHz) are performed. A portion explosive sample is inserted into shim 2mm in length trimmed flush with the faces shim. Two-port S-parameter were conducted on explosive; empty similarly characterized. Using standard equations measured shim, complex data obtained filled optimized to four free parameters — permittivity distance...

Dielectric measurements of plastic explosives using a loaded waveguide technique via vector network analyzer and banded millimeter wave extender modules operating at V-band (50 to 75 GHz) are performed. A portion an explosive sample is inserted into shim 2 mm in length trimmed flush with the faces shim. Two-port S-parameter conducted on explosive; empty similarly characterized. Using standard equations measured shim, complex data obtained filled optimized four free parameters—complex...