The Experts below are selected from a list of 4611 Experts worldwide ranked by ideXlab platform
Kelsie Simons - One of the best experts on this subject based on the ideXlab platform.
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forensic analysis of a single particle of partially burnt Gunpowder by solid phase micro extraction gas chromatography nitrogen phosphorus detector
Journal of Chromatography A, 2009Co-Authors: Garrett Lee Burleson, Brittney Gonzalez, Kelsie SimonsAbstract:Solid phase micro-extraction (SPME) was adopted to extract organic gun shot residues (OGSRs) from a single particle of partially burnt Gunpowder. The partially burnt particle samples were collected from gun shot residue (GSR) deposited near the target areas. OGSRs, such as diphenylamine (DPA), methyl centralite (MC), ethyl centralite (EC), from only one single particle of partially burnt Gunpowder were successfully extracted by SPME and analyzed by a gas chromatography coupled to a nitrogen phosphorus detector (GC-NPD). The results confirmed that the new extraction procedure is capable of extracting trace amount of MC and EC as signature molecules for the identification of GSR. The method represents a solvent-free extraction as a complementary analytical procedure for the forensic analysis of GSR-related evidences. The new extraction scheme with the capability of analyzing single particle of partially burnt Gunpowder can also be applied to the identification of explosive residues, such as in post-blast investigations of improvised explosive devices.
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Forensic analysis of a single particle of partially burnt Gunpowder by solid phase micro-extraction–gas chromatography-nitrogen phosphorus detector
Journal of Chromatography A, 2009Co-Authors: Garrett Lee Burleson, Brittney Gonzalez, Kelsie Simons, Jorn C. C. YuAbstract:Solid phase micro-extraction (SPME) was adopted to extract organic gun shot residues (OGSRs) from a single particle of partially burnt Gunpowder. The partially burnt particle samples were collected from gun shot residue (GSR) deposited near the target areas. OGSRs, such as diphenylamine (DPA), methyl centralite (MC), ethyl centralite (EC), from only one single particle of partially burnt Gunpowder were successfully extracted by SPME and analyzed by a gas chromatography coupled to a nitrogen phosphorus detector (GC-NPD). The results confirmed that the new extraction procedure is capable of extracting trace amount of MC and EC as signature molecules for the identification of GSR. The method represents a solvent-free extraction as a complementary analytical procedure for the forensic analysis of GSR-related evidences. The new extraction scheme with the capability of analyzing single particle of partially burnt Gunpowder can also be applied to the identification of explosive residues, such as in post-blast investigations of improvised explosive devices.
Garrett Lee Burleson - One of the best experts on this subject based on the ideXlab platform.
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forensic analysis of a single particle of partially burnt Gunpowder by solid phase micro extraction gas chromatography nitrogen phosphorus detector
Journal of Chromatography A, 2009Co-Authors: Garrett Lee Burleson, Brittney Gonzalez, Kelsie SimonsAbstract:Solid phase micro-extraction (SPME) was adopted to extract organic gun shot residues (OGSRs) from a single particle of partially burnt Gunpowder. The partially burnt particle samples were collected from gun shot residue (GSR) deposited near the target areas. OGSRs, such as diphenylamine (DPA), methyl centralite (MC), ethyl centralite (EC), from only one single particle of partially burnt Gunpowder were successfully extracted by SPME and analyzed by a gas chromatography coupled to a nitrogen phosphorus detector (GC-NPD). The results confirmed that the new extraction procedure is capable of extracting trace amount of MC and EC as signature molecules for the identification of GSR. The method represents a solvent-free extraction as a complementary analytical procedure for the forensic analysis of GSR-related evidences. The new extraction scheme with the capability of analyzing single particle of partially burnt Gunpowder can also be applied to the identification of explosive residues, such as in post-blast investigations of improvised explosive devices.
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Forensic analysis of a single particle of partially burnt Gunpowder by solid phase micro-extraction–gas chromatography-nitrogen phosphorus detector
Journal of Chromatography A, 2009Co-Authors: Garrett Lee Burleson, Brittney Gonzalez, Kelsie Simons, Jorn C. C. YuAbstract:Solid phase micro-extraction (SPME) was adopted to extract organic gun shot residues (OGSRs) from a single particle of partially burnt Gunpowder. The partially burnt particle samples were collected from gun shot residue (GSR) deposited near the target areas. OGSRs, such as diphenylamine (DPA), methyl centralite (MC), ethyl centralite (EC), from only one single particle of partially burnt Gunpowder were successfully extracted by SPME and analyzed by a gas chromatography coupled to a nitrogen phosphorus detector (GC-NPD). The results confirmed that the new extraction procedure is capable of extracting trace amount of MC and EC as signature molecules for the identification of GSR. The method represents a solvent-free extraction as a complementary analytical procedure for the forensic analysis of GSR-related evidences. The new extraction scheme with the capability of analyzing single particle of partially burnt Gunpowder can also be applied to the identification of explosive residues, such as in post-blast investigations of improvised explosive devices.
Brittney Gonzalez - One of the best experts on this subject based on the ideXlab platform.
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forensic analysis of a single particle of partially burnt Gunpowder by solid phase micro extraction gas chromatography nitrogen phosphorus detector
Journal of Chromatography A, 2009Co-Authors: Garrett Lee Burleson, Brittney Gonzalez, Kelsie SimonsAbstract:Solid phase micro-extraction (SPME) was adopted to extract organic gun shot residues (OGSRs) from a single particle of partially burnt Gunpowder. The partially burnt particle samples were collected from gun shot residue (GSR) deposited near the target areas. OGSRs, such as diphenylamine (DPA), methyl centralite (MC), ethyl centralite (EC), from only one single particle of partially burnt Gunpowder were successfully extracted by SPME and analyzed by a gas chromatography coupled to a nitrogen phosphorus detector (GC-NPD). The results confirmed that the new extraction procedure is capable of extracting trace amount of MC and EC as signature molecules for the identification of GSR. The method represents a solvent-free extraction as a complementary analytical procedure for the forensic analysis of GSR-related evidences. The new extraction scheme with the capability of analyzing single particle of partially burnt Gunpowder can also be applied to the identification of explosive residues, such as in post-blast investigations of improvised explosive devices.
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Forensic analysis of a single particle of partially burnt Gunpowder by solid phase micro-extraction–gas chromatography-nitrogen phosphorus detector
Journal of Chromatography A, 2009Co-Authors: Garrett Lee Burleson, Brittney Gonzalez, Kelsie Simons, Jorn C. C. YuAbstract:Solid phase micro-extraction (SPME) was adopted to extract organic gun shot residues (OGSRs) from a single particle of partially burnt Gunpowder. The partially burnt particle samples were collected from gun shot residue (GSR) deposited near the target areas. OGSRs, such as diphenylamine (DPA), methyl centralite (MC), ethyl centralite (EC), from only one single particle of partially burnt Gunpowder were successfully extracted by SPME and analyzed by a gas chromatography coupled to a nitrogen phosphorus detector (GC-NPD). The results confirmed that the new extraction procedure is capable of extracting trace amount of MC and EC as signature molecules for the identification of GSR. The method represents a solvent-free extraction as a complementary analytical procedure for the forensic analysis of GSR-related evidences. The new extraction scheme with the capability of analyzing single particle of partially burnt Gunpowder can also be applied to the identification of explosive residues, such as in post-blast investigations of improvised explosive devices.
Jin Yong Jiang - One of the best experts on this subject based on the ideXlab platform.
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Study on the Combustion Mechanism and Models of Gunpowder Composite Welding Rod
Advanced Materials Research, 2013Co-Authors: Xiao Biao Jia, Jin Yong Jiang, Wen Ping Chang, Hao Nan Jia, Tao ZhangAbstract:The physical model of the flame of Gunpowder composite welding rod (GCWR) is built based on the flame topography and the combustion mechanism of thermite. The chemical reactions in different flame regions are fixed with the physical model, combustion characteristics of thermite and Gunpowder combustion theory. The combustion mathematic model on the relationship of combustion velocity of GCWR with thermite content is fixed with the concept of unit volume combustion heat. At last, the results of the test indicate that the rates of combustion obtained by theoretical arithmetic and test are similar.
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Study on the Mechanical Property of Gunpowder Composite Welding Rod
Applied Mechanics and Materials, 2012Co-Authors: Jin Yong Jiang, Xiao Biao Jia, Lu Ming Jiang, Wen Ping Chang, Hao Nan JiaAbstract:Gunpowder composite welding rod is a new type of welding material, which is mainly composed with Gunpowder and thermite. This welding rod has the following characteristics: (1) portable welding rod; (2) simple and safe in operation; (3) high controllability of combustion; (4) don’t need outside energy source, et al. obviously, all characteristics indicate that this welding material can satisfy the demand of field emergency or civil device emergency. In this article, the mainly components and characteristics of Gunpowder composite welding rod are introduced in detail.
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Study on the energy density of Gunpowder heat source
2011 International Conference on Materials for Renewable Energy & Environment, 2011Co-Authors: Wen Ping Chang, Jin Yong JiangAbstract:In order to reapply the waste energetic materials as welding heat source, in this article, the energy densities of several types of Gunpowder were calculated with the equation of energy density. The results show that the energy densities of powders are very low, which are impossible to weld metal. Otherwise, the effects of aluminium powder and thermite on the energy density of Gunpowder were investigated, the results show that the effects of aluminium powder and thermite are different, to the former the effect is not evident, but to the later the energy density can be elevated obviously by adding it.
Carmen García-ruiz - One of the best experts on this subject based on the ideXlab platform.
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Surface-enhanced Raman spectroscopy for the analysis of smokeless Gunpowders and macroscopic gunshot residues
Analytical and Bioanalytical Chemistry, 2016Co-Authors: María López-lópez, Carmen García-ruiz, Virginia Merk, Janina KneippAbstract:Gunshot residues (GSR) result from the discharge of a firearm being a potential piece of evidence in criminal investigations. The macroscopic GSR particles are basically formed by burned and non-burned Gunpowder. Motivated by the demand of trace analysis of these samples, in this paper, the use of surface-enhanced Raman scattering (SERS) was evaluated for the analysis of Gunpowders and macroscopic GSR particles. Twenty-one different smokeless Gunpowders were extracted with ethanol. SERS spectra were obtained from the diluted extracts using gold nanoaggregates and an excitation wavelength of 633 nm. They show mainly bands that could be assigned to the stabilizers diphenylamine and ethylcentralite present in the Gunpowders. Then, macroscopic GSR particles obtained after firing two different ammunition cartridges on clothing were also measured using the same procedure. SERS allowed the detection of the particles collected with an aluminum stub from cloth targets without interferences from the adhesive carbon. The results demonstrate the great potential of SERS for the analysis of macroscopic GSR particles. Furthermore, they indicate that the grain-to-grain inhomogeneity of the Gunpowders needs to be considered. Graphical Abstract SERS allows the detection of GSR particles collected with adhesive stubs from cloth targets using gold nanoaggregates and an excitation wavelength of 633 nm.
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Diphenylamine and derivatives as predictors of Gunpowder age by means of HPLC and statistical models.
Talanta, 2013Co-Authors: María López-lópez, J.carlos Bravo, Carmen García-ruiz, M. TorreAbstract:The Gunpowder age is information of great importance that could help to establish safety regulations related to the propellants use and manipulation. In this work, a forced aging treatment (65°C for 120 days) was applied to four Gunpowders stabilized with diphenylamine (DPA). The evolution of DPA and derivatives (N-nitroso-DPA, 2-nitro-DPA, 4-nitro-DPA, and 4-4'-dinitro-DPA) concentration during the days was leaded by High Performance Liquid Chromatography (HPLC). The variation with time of the peak areas of these compounds was used to construct different statistical models that could predict the Gunpowders age. These models were validated using nitrocellulose-based Gunpowders of known manufacture date. Models that best predicted the Gunpowder age provided prediction errors lower than 6, 4, and 2 years for single-base Gunpowders with dinitrotoluene (≥ 10%(m/m)), single-base Gunpowders and double-base Gunpowders, respectively.
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Comparative analysis of smokeless Gunpowders by Fourier transform infrared and Raman spectroscopy
Analytica Chimica Acta, 2012Co-Authors: María López-lópez, Jose Luis Ferrando, Carmen García-ruizAbstract:Abstract Fourier Transform Infrared (FTIR) and Raman spectroscopic techniques were used to perform a comparative study of the spectral profiles of single-base, double-base and triple-base smokeless Gunpowders. Preliminary results based on visual comparison of the spectra point out that spectra obtained by both vibrational techniques were useful for a rapid identification of Gunpowders containing dinitrotoluene as one of the major components and triple-base Gunpowders. Additionally, the Raman spectra of Gunpowders with diphenylamine in its primary composition showed a characteristic band, assigned to 2-nitro-diphenylamine, allowing the identification of this type of Gunpowders. Further differentiation among the spectra of different types of smokeless Gunpowders obtained by both vibrational spectroscopic techniques was investigated by discriminant analysis. Different analyses were applied to spectral data considering the different composition of Gunpowders. The presence or absence of different compounds (such as dinitrotoluene, diphenylamine or dibutyl phthalate) or the type of Gunpowder according to the number of active components (single-base or double-base Gunpowder) has been taken into account. FTIR and Raman spectroscopy in combination with discriminant analyses were successful tools of forensic interest for the classification of Gunpowders and the possible identification of unknown samples of Gunpowders.
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New protocol for the isolation of nitrocellulose from Gunpowders: utility in their identification.
Talanta, 2010Co-Authors: María López-lópez, Jose Luis Ferrando, María Angeles Fernández De La Ossa, Jorge Sáiz Galindo, Alfonso Vega, Mercedes Torre, Carmen García-ruizAbstract:In this work, a new approach for the isolation of nitrocellulose from smokeless Gunpowders has been developed. A multistep solvent extraction method was needed to purify nitrocellulose contained in Gunpowders. For single-base or double-base Gunpowders six consecutive solvent extractions were selected: three extractions with methanol (to remove nitroglycerin, 2,4-dinitrotoluene, ethyl-centralite, diphenylamine, and diphenylamine derivatives); one extraction with dichloromethane (to remove colorants and plasticizers of organic nature); one extraction with methanol (to facilitate a final polar extraction); and one extraction with water (to remove ionic components) were necessary at 35 degrees C. For the triple-base Gunpowder studied, eight solvent extractions were needed due to a high concentration of the water-soluble nitroguanidine was present. In addition to the same five initial phases used for the single-base and double-base Gunpowders, three water extraction phases at a higher temperature (75 degrees C instead of 35 degrees C) were also needed. A final step to solubilize nitrocellulose in methyl ethyl ketone was used to remove inert components (mainly graphite). Nitrocellulose isolated from these propellants was characterized by Fourier-Transformed Infrared Spectroscopy (FTIR spectroscopy). The same FTIR spectra were observed for nitrocelluloses isolated from different types of Gunpowders. A comparison of FTIR spectra of nitrocellulose samples of different nitration degree evidenced that the bands regions most affected by this factor were: 3600-3400cm(-1), corresponding to the stretching vibrations of residual hydroxyl groups; 1200-1000cm(-1), attributed to the valence vibrations nuCO of the glucopyranose cycle; and 750-690cm(-1), assigned to vibrations of the nitrate group. In both cases, the bands appearing in these regions were more pronounced in the spectra of nitrocellulose samples of low nitration degree.
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New protocol for the isolation of nitrocellulose from Gunpowders: Utility in their identification
Talanta, 2010Co-Authors: María López-lópez, M. Torre, Jose Luis Ferrando, María Angeles Fernández De La Ossa, Jorge Sáiz Galindo, Alfonso Vega, Carmen García-ruizAbstract:Abstract In this work, a new approach for the isolation of nitrocellulose from smokeless Gunpowders has been developed. A multistep solvent extraction method was needed to purify nitrocellulose contained in Gunpowders. For single-base or double-base Gunpowders six consecutive solvent extractions were selected: three extractions with methanol (to remove nitroglycerin, 2,4-dinitrotoluene, ethyl-centralite, diphenylamine, and diphenylamine derivatives); one extraction with dichloromethane (to remove colorants and plasticizers of organic nature); one extraction with methanol (to facilitate a final polar extraction); and one extraction with water (to remove ionic components) were necessary at 35 °C. For the triple-base Gunpowder studied, eight solvent extractions were needed due to a high concentration of the water-soluble nitroguanidine was present. In addition to the same five initial phases used for the single-base and double-base Gunpowders, three water extraction phases at a higher temperature (75 °C instead of 35 °C) were also needed. A final step to solubilize nitrocellulose in methyl ethyl ketone was used to remove inert components (mainly graphite). Nitrocellulose isolated from these propellants was characterized by Fourier-Transformed Infrared Spectroscopy (FTIR spectroscopy). The same FTIR spectra were observed for nitrocelluloses isolated from different types of Gunpowders. A comparison of FTIR spectra of nitrocellulose samples of different nitration degree evidenced that the bands regions most affected by this factor were: 3600–3400 cm −1 , corresponding to the stretching vibrations of residual hydroxyl groups; 1200–1000 cm −1 , attributed to the valence vibrations ν CO of the glucopyranose cycle; and 750–690 cm −1 , assigned to vibrations of the nitrate group. In both cases, the bands appearing in these regions were more pronounced in the spectra of nitrocellulose samples of low nitration degree.