Добірка наукової літератури з теми "Tri Nitro Toluene"

Plane wave generator is normally composed of two explosives having dissimilar detonation velocity. It is used for directing the spherically outgoing shock wave front to a planar form. Plane wave generators are utilized to find material behavior under dynamic loading. This paper presents the shock arrival time for two plane wave generators by developed Matlab code and its comparison with Ansys Autodyn. The diameter of both plane wave generators is kept the same. One plane wave generator is composed of Octogen and Barium Nitrate and the other is composed of Octogen and Tri Nitro Toluene. Obtained results were surprisingly in agreement. Maximum and minimum obtained flatness for the plane wave were ±0.56 and ±0.08ms respectively within the whole diameter of the plane wave generator. The developed code can be utilized to find the profile of a plane wave generator, minimizing the time and cost many times.

This paper presents the results of an experimental test conducted on the blast resistance of a steel plate. A supporting steel frame on a concrete foundation was designed for testing a steel plate target against blast loading. A 1220 mm × 2140 mm × 10 mm steel plate was tested and subjected to the explosion of 50 kg of TNT (tri-nitro toluene) at a stand-off distance of 20 m. Data collected from the specimen included the strain and deflection of the steel plate. The test data were analyzed to evaluate the performance of the plate. The test results were compared with the results of Autodyn, which is a finite element method-based commercial software. The analytical results showed minor differences from the test results when the boundary conditions of the steel plate assumed that the upper and lower sides were fixed and the other sides were free.

The kinetics of hexogen coating with polyurethane-based hydroxyl-terminated polybutadiene (HTPB) using infrared spectrometry was investigated. The kinetics model was evaluated through reaction steps: (1) hydroxyl and isocyanate to produce urethane, (2) urethane and isocyanate to produce allophanate, and (3) nitro and isocyanate to produce diazene oxide and carbon dioxide. HTPB, ethyl acetate, TDI (toluene diisocyanate), and hexogen were mixed for 60 min at 40 °C. The sample was withdrawn and analyzed with infrared spectroscopy every ten minutes at reference wavelengths of 2270 (the specific absorption for isocyanate groups) and 1768 cm−1 (the specific absorption for N=N groups). The solvent was vaporized; then, the coated hexogen was cured in the oven for 7 days at 60 °C. The effect of temperature on the coating kinetics was studied by adjusting the reaction temperature at 40, 50, and 60 °C. This procedure was repeated with IPDI (isophorone diisocyanate) as a curing agent. The reaction rate constant, k3, was calculated from an independent graphic based on increasing diazene oxide concentration every ten minutes. The reaction rate constants, k1 and k2, were numerically calculated using the Newton–Raphson and Runge–Kutta methods based on decreasing isocyanate concentrations. The activation energy of those steps was 1178, 1021, and 912 kJ mole−1. The reaction rate of hexogen coating with IPDI was slightly faster than with TDI.

Abstract. Despite the high abundance of secondary aerosols in the atmosphere, their formation mechanisms remain poorly understood. In this study, the Master Chemical Mechanism (MCM) and the Chemical Aqueous-Phase Radical Mechanism (CAPRAM) are used to investigate the multiphase formation and processing of secondary aerosol constituents during the advection of air masses towards the measurement site of Mt. Tai in northern China. Trajectories with and without chemical–cloud interaction are modeled. Modeled radical and non-radical concentrations demonstrate that the summit of Mt. Tai, with an altitude of ∼1.5 km a.m.s.l., is characterized by a suburban oxidants budget. The modeled maximum gas-phase concentrations of the OH radical are 3.2×106 and 3.5×106 molec. cm−3 in simulations with and without cloud passages in the air parcel, respectively. In contrast with previous studies at Mt. Tai, this study has modeled chemical formation processes of secondary aerosol constituents under day vs. night and cloud vs. non-cloud cases along the trajectories towards Mt. Tai in detail. The model studies show that sulfate is mainly produced in simulations where the air parcel is influenced by cloud chemistry. Under the simulated conditions, the aqueous reaction of HSO3- with H2O2 is the major contributor to sulfate formation, contributing 67 % and 60 % in the simulations with cloud and non-cloud passages, respectively. The modeled nitrate formation is higher at nighttime than during daytime. The major pathway is aqueous-phase N2O5 hydrolysis, with a contribution of 72 % when cloud passages are considered and 70 % when they are not. Secondary organic aerosol (SOA) compounds, e.g., glyoxylic, oxalic, pyruvic and malonic acid, are found to be mostly produced from the aqueous oxidations of hydrated glyoxal, hydrated glyoxylic acid, nitro-2-oxopropanoate and hydrated 3-oxopropanoic acid, respectively. Sensitivity studies reveal that gaseous volatile organic compound (VOC) emissions have a huge impact on the concentrations of modeled secondary aerosol compounds. Increasing the VOC emissions by a factor of 2 leads to linearly increased concentrations of the corresponding SOA compounds. Studies using the relative incremental reactivity (RIR) method have identified isoprene, 1,3-butadiene and toluene as the key precursors for glyoxylic and oxalic acid, but only isoprene is found to be a key precursor for pyruvic acid. Additionally, the model investigations demonstrate that an increased aerosol partitioning of glyoxal can play an important role in the aqueous-phase formation of glyoxylic and oxalic acid. Overall, the present study is the first that provides more detailed insights in the formation pathways of secondary aerosol constituents at Mt. Tai and clearly emphasizes the importance of aqueous-phase chemical processes on the production of multifunctional carboxylic acids.

This study aimed to find an additional analytical reference procedure to verify the accuracy of single beam Spectrophotometer results that used to determine the concentration of nitro compound pollutants such as TNT, DNT, and MNT (Tri Nitro Toluene, Di Nitro toluene, and Mono Nitro Toluene respectively) in treated acidic wastewater generated from TNT manufacturing. This procedure was tested and confirmed to be a reference for a single-beam spectrophotometer. In this study 10 samples with known concentrations were taken and prepared for colorimetric analysis, the concentrations gradient from 10mg/L up to 60mg/L to make a ruler with gradient color, this ruler was suitable for high concentration samples but to specify the low concentration samples the procedure depended on adding a known concentration to the unknown concentration sample then this added concentration transferred the samples from unspecified color to specified color on the ruler consisted by known concentration mentioned above, the concentration of unknown concentration samples were specified by taking the concentration corresponding to the ruler color a subtracting the value of added concentration and the value of the remains was sample concentration. This study proved the reliability of this procedure to confirm single-beam spectrophotometer results, determining low concentration value of unknown concentration sample of TNT acidic wastewater, and then it can be used as a substituent of spectrophotometer in the event of malfunctions.

2,4,6-trinitrotoluene (TNT) degradation is of interest in environmental remediation, demilitarization, and national security. Electrochemical TNT reduction to 2,4,6-triaminotoluene is potentially energy efficient and operable at ambient conditions. Determining an elementary...

ABSTRACTA nano-scale biosensor chip surface was fabricated using dinitro-phenylated key hole limpet (DNP-KLH) protein conjugate as ligand supported by underlying 11-amino 1-undecanethiol hydrochloride(AUT) self assembled monolayer (SAM) and bis sulfosuccinimidyl suberate(BS3) as crosslinker. Bioactive thin films were fabricated over gold chip via layer-by-layer self assembly methods. Biomolecular interaction between substrate specific anti-TNT antibody and DNP-KLH conjugate surface was monitored through surface plasmon resonance based optical sensor. The quantitation of tri-nitro toluene(TNT) on this bioactive surface was done using the solution based competitive inhibition assay. The DNP-KLH surface biosensor has shown a detection limit of 0.14 ng/ml(140 ppt) for TNT molecule. The detection limit of surface plasmon resonance(SPR) biosensor was further enhanced by using goat anti mouse antibody to the 0.002 ng/ml for TNT analyte. This TNT specific biosensor holds the promise to be one of most sensitive sensor surface under indirect competitive assay format. A short injection (12 sec) of 10 mM Glycine-HCl solution was found adequate for regeneration of DNP-KLH surface for repeated use.

This paper aims at assessing a custom numerical procedure built to predict the level of stress in the structural components and equipment in proximity of a cannon-like weapon system when firing. In such a blast scenario, the structures adjacent to a gun may undergo sudden and unwanted damages, since they are commonly subjected to the blast load due to the impingement and propagation of the shock waves expanding from the weapon muzzle. The proposed procedure pertains the coupled use of an in-house developed tool (GUNWave3D) based on the power-law scaling technique and a general-purpose commercial fast dynamic solver to compute the structural response of the loaded components. The in-house tool, in particular, allows one to rapidly calculate the blast parameters over the surfaces of the items of interest in the function of the weapon characteristics and launch conditions, also accounting for the asymmetric shape characterizing the gun blast wave. Taking as reference the numerical free field peak overpressure profiles of a 30 mm gun, whose blast quantities were already validated in a previously published work, the final stage of the assessment was accomplished. Such an estimation consists of the comparison between the structural stresses calculated using the blast loads predicted through the in-house tool and those computed adopting the free spherical air blast of the tri-nitro-toluene model. This operation has the objective to quantify the discrepancy between the computational results of two Lagrangian techniques that can be alternatively adopted in industrial gun blast design procedures and methodologies.

ABSTRACTEpoxy-based copolymers were synthesized with N,N-diglycidyl aniline (DGA) and aniline (An), called poly(DGA-co-An), where azo coupling reactions were performed using amino benzonitrile (ABN) and nitro aniline (NA). Two azopolymers were dissolved with both tetrahydrofuran (THF)/dioxane complex solvent and THF to compare the diffraction efficiencies according to solvent. The thin films spin-cast with THF/dioxane showed the better diffractive efficiency than with THF due to the high boil point of the residual dioxane. The azopolymers of two azo bonds were spin-coated at 800 and 1300 rpm where the thicker film showed the better diffractive efficiency. The epoxy-based copolymers synthesized with diglycidyl ether of bisphenol A (DGEBA) and aniline (An) or 3-hydroxyl aniline (HAn) were coupled with hydroxyl nitro amino benzene (HNAB). Hydroxyl groups in chromophores helped to form hydrogen bonding with the nitrogen atoms in the azo bonds and prevented photoisomerization, showing no surface relief gratings under a normal laser intensity of 100 mW/cm2. Polyurethane-based azopolymers were synthesized with disperse orange 17 (DO17) and toluene-2,4-diisocyanate (TDI), which were no hydroxide groups in the main chains, and showed the better diffractive efficiency than the epoxy-based azopolymers with nitro substituents.

According to the assessments of the United Nations, there are more than 100 million mines lying buried in various conflict zones of many countries in the world. As per their assessment, many thousand casualties happen every year. Most of the demining operations are generally carried out after the conflicts end. This task is one of the most challenging and always a risky operation. There are various demining equipment available world-wide to perform this job in addition to the manual demining of minefield by trained soldiers. Explosive loading on machine components of service vehicles during military operations is a complex process. The complexity stems from unpredictable detonation, complicated component geometry and geographical terrain, debris effects etc. Consequently, the damage on structural components becomes highly unpredictable. There are too many other environmental parameters contributing to the final damage. In this context, both high explosive loading and material response behave like independent random variables. Blast loading on tubes and plates is vital in the design of combat and demining equipment of real life situations. Therefore, study of plain circular tubes (PCT), perforated circular tubes (PRCT) and plates subjected to blast loading due to explosion of high explosives such as TNT, RDX and TETRYL has been considered in the present thesis. Due to various design constraints, it is extremely difficult to design these components for desired service life for high quantum of blast load. This thesis explains the uses of perforations for handling this inevitable and extreme condition of loading on the target components. It is pertinent to note that the various blast parameters such as time of sight, overpressure, impulse etc. available in the literature are not reliable for close range of explosion of high explosive for scaled distance in order of 0.40 m/kg1/3. Therefore, it is essential to establish and quantify some of these parameters for close range blast, which will be useful for real life design problems. Accordingly, the present thesis covers experimental and numerical study of plain circular tube (PCT) and perforated circular tube (PRCT) under blast loading of high explosive. iv CONWEP code has been used for numerical simulation of PCT and PRCT subjected to blast loading. Some important blast parameters have been established in this research. It has been shown that there is approximately 58 % reduction in blast impact on the tube due to use of perforation. Square and hexagonal pattern of perforation has been studied. Theory of strong explosion has been discussed in the present thesis. Non-dimensional time and length scale has been proposed in place of scaled distance. Also, simplified empirical formula has been proposed for estimation of time of sight for close range blast covering scaled distance 0.40 m/kg1/3 - 0.45 m/kg1/3.
Defence Research & Development Organisation (DRDO)