Готові списки джерел за темами / Chemical explosive mode analysis

Добірка наукової літератури з теми "Chemical explosive mode analysis"

Автор: Grafiati

Опубліковано: 6 вересня 2023

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Статті в журналах з теми "Chemical explosive mode analysis"

LU, T. F., C. S. YOO, J. H. CHEN, and C. K. LAW. "Three-dimensional direct numerical simulation of a turbulent lifted hydrogen jet flame in heated coflow: a chemical explosive mode analysis." Journal of Fluid Mechanics 652 (May 19, 2010): 45–64. http://dx.doi.org/10.1017/s002211201000039x.

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A chemical explosive mode analysis (CEMA) was developed as a new diagnostic to identify flame and ignition structure in complex flows. CEMA was then used to analyse the near-field structure of the stabilization region of a turbulent lifted hydrogen–air slot jet flame in a heated air coflow computed with three-dimensional direct numerical simulation. The simulation was performed with a detailed hydrogen–air mechanism and mixture-averaged transport properties at a jet Reynolds number of 11000 with over 900 million grid points. Explosive chemical modes and their characteristic time scales, as well as the species involved, were identified from the Jacobian matrix of the chemical source terms for species and temperature. An explosion index was defined for explosive modes, indicating the contribution of species and temperature in the explosion process. Radical and thermal runaway can consequently be distinguished. CEMA of the lifted flame shows the existence of two premixed flame fronts, which are difficult to detect with conventional methods. The upstream fork preceding the two flame fronts thereby identifies the stabilization point. A Damköhler number was defined based on the time scale of the chemical explosive mode and the local instantaneous scalar dissipation rate to highlight the role of auto-ignition in affecting the stabilization points in the lifted jet flame.

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Xu, Chao, Ji-Woong Park, Chun Sang Yoo, Jacqueline H. Chen, and Tianfeng Lu. "Identification of premixed flame propagation modes using chemical explosive mode analysis." Proceedings of the Combustion Institute 37, no. 2 (2019): 2407–15. http://dx.doi.org/10.1016/j.proci.2018.07.069.

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Wu, Wantong, Ying Piao, Qing Xie, and Zhuyin Ren. "Flame Diagnostics with a Conservative Representation of Chemical Explosive Mode Analysis." AIAA Journal 57, no. 4 (April 2019): 1355–63. http://dx.doi.org/10.2514/1.j057994.

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Shan, Ruiqin, Chun Sang Yoo, Jacqueline H. Chen, and Tianfeng Lu. "Computational diagnostics for n-heptane flames with chemical explosive mode analysis." Combustion and Flame 159, no. 10 (October 2012): 3119–27. http://dx.doi.org/10.1016/j.combustflame.2012.05.012.

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Xu, Chao, Muhsin M. Ameen, Sibendu Som, Jacqueline H. Chen, Zhuyin Ren, and Tianfeng Lu. "Dynamic adaptive combustion modeling of spray flames based on chemical explosive mode analysis." Combustion and Flame 195 (September 2018): 30–39. http://dx.doi.org/10.1016/j.combustflame.2018.05.019.

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Wang, Lei, Yong Jiang, and Rong Qiu. "Chemical Explosive Mode Analysis for Local Reignition Scenarios in H2/N2 Turbulent Diffusion Flames." Energy & Fuels 31, no. 9 (September 6, 2017): 9939–49. http://dx.doi.org/10.1021/acs.energyfuels.6b03175.

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Hu, Yupeng, Jiawen Liu, Qiang Wan, Meng Zhang, and Minghai Li. "Numerical Study of PBX 9501 Explosive Combustion Process in Confined Space." Processes 11, no. 7 (July 10, 2023): 2056. http://dx.doi.org/10.3390/pr11072056.

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Explosives combustion is primarily classified into conductive and convective combustion. In situations where confinement is sufficiently strong, the instantaneous high pressure generated by convective combustion in cracks can cause rapid fragmentation of the explosive matrix, resulting in a significant increase in the combustion surface area and triggering a high-intensity reaction with potentially catastrophic consequences. Therefore, the study of convective combustion in cracks is crucial for ensuring the safety of weapons and explosives. Previous simulation studies have primarily used finite element analysis software, which has excellent performance in handling explosive detonation processes. However, its accuracy in describing gas behavior between explosives and constrained containers is limited. This study divides the combustion process of a pre-cracked explosive in a confined space into four stages based on reasonable assumptions and simplifications. We developed a simulation method that combines the Arrhenius formula with the MWSD model to model the combustion rate of the explosive. By introducing a correction coefficient, Con, to the Arrhenius formula, the formula and MWSD model control the first and third stages of explosive combustion, respectively, while smoothly transitioning during the second stage. We used this method to numerically simulate the experimental results of Shang Hailin et al. on a crack width of 50 μm. The simulation results include the temperature field and pressure field of the first three stages of explosive combustion and the pressure rise curve of the pressure measurement point at the same location, as in the experiment. The simulation results are consistent with the experimental results.

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Cifuentes, Luis, Ehsan Fooladgar, and Christophe Duwig. "Chemical Explosive Mode Analysis for a Jet-in-Hot-Coflow burner operating in MILD combustion." Fuel 232 (November 2018): 712–23. http://dx.doi.org/10.1016/j.fuel.2018.05.171.

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Luo, Zhaoyu, Chun Sang Yoo, Edward S. Richardson, Jacqueline H. Chen, Chung K. Law, and Tianfeng Lu. "Chemical explosive mode analysis for a turbulent lifted ethylene jet flame in highly-heated coflow." Combustion and Flame 159, no. 1 (January 2012): 265–74. http://dx.doi.org/10.1016/j.combustflame.2011.05.023.

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Szachogluchowicz, Ireneusz, Lucjan Sniezek, Krzysztof Grzelak, Heorhiy Sulym, Ihor Turchyn, and Iaroslav Pasternak. "The Analytical Model of Stress Zone Formation of Ti4Al4V/AA1050/AA2519 Laminate Produced by Explosive Bonding." Metals 9, no. 7 (July 12, 2019): 779. http://dx.doi.org/10.3390/met9070779.

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This paper contains an analytical description of the deformation of the upper layer AA2519/AA1050/Ti6Al4V laminate produced by an explosive bonding method. The basic parameters of the explosive welding process that influence the quality of the bonding are the detonation velocity of the explosive, the explosion energy, and the impact angle of the combined materials. The developed description uses the theory of elastodynamic character of materials deformation at the connection point due to local traction load. The presence of high pressure during joining was limited to the region where the plane surface moving with a constant subsonic velocity. An analytical description of the residual stresses distribution was also a performer. Results of analytical investigations were verified by structure examination of the bond zone. The work was supplemented by the chemical composition analysis of the base materials and a monotonic stretching test characterizing the basic mechanical properties of the produced laminate.

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Більше джерел

Дисертації з теми "Chemical explosive mode analysis"

Keene, Stephen G. "An analysis of the Naval Innovation Laboratory's virtual work environment-based management information system for application in joint service explosive ordnance disposal notional concepts management." Monterey, California : Naval Postgraduate School, 2009. http://edocs.nps.edu/npspubs/scholarly/MBAPR/2009/Dec/09Dec%5FKeene%5FMBA.pdf.

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"Submitted in partial fulfillment of the requirements for the degree of Master of Business Administration from the Naval Postgraduate School, December 2009."
Advisor(s): Boudreau, Michael ; Brinkley, Douglas. "December 2009." "MBA Professional report"--Cover. Description based on title screen as viewed on January 28, 2010. Author(s) subject terms: Notional Concept, Virtual Work Environment, Management Information System, Urgent Universal Needs Statement, share drive-based database. Includes bibliographical references (p. 65-66). Also available in print.

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Bui, Lan Nang. "Application of neural network analysis to the thickness-shear mode chemical sensor." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1999. http://www.collectionscanada.ca/obj/s4/f2/dsk1/tape7/PQDD_0011/NQ59096.pdf.

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Solam, Anupama. "Analytical and Numerical Analysis of Low Optical Overlap Mode Evanescent Wave Chemical Sensors." Ohio University / OhioLINK, 2009. http://rave.ohiolink.edu/etdc/view?acc_num=ohiou1247498921.

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Bradshaw, John Thomas. "BROADBAND COUPLING INTO SINGLE MODE, PLANAR INTEGRATED OPTICAL WAVEGUIDE STRUCTURES FOR SPECTRAL ANALYSIS OF THIN FILM ANALYTES AND INTERFACIAL CHEMICAL ENVIRONMENTS." Diss., Tucson, Arizona : University of Arizona, 2005. http://etd.library.arizona.edu/etd/GetFileServlet?file=file:///data1/pdf/etd/azu%5Fetd%5F1144%5F1%5Fm.pdf&type=application/pdf.

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Raj, Sharad K. "Chemical Information Based Elastic Network Model: A Novel Way To Identification Of Vibration Frequencies In Proteins." Amherst, Mass. : University of Massachusetts Amherst, 2009. http://scholarworks.umass.edu/theses/261/.

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Brunson, Kennard Marcellus. "Synthesis and Characterization of methylene bis (p-cyclohexyl isocyanate)-poly (tetramethyl oxide) based Polyurethane Elastomers." VCU Scholars Compass, 2005. http://scholarscompass.vcu.edu/etd/1211.

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This research concerns the development and characterization of methylene bis (p-cyclohexyl isocyanate/butanediol) (HMDI/BD) based polyurethanes used in connection with surface-active anti-microbial polyurethanes. Previously studied polyurethanes having an isophorone diisocyanate/butanediol (IPDI/BD) hard block contaminated water during dynamic contact angle (DCA) analyses. This contamination by unknown species confounds results from biocidal studies and jeopardizes the use of the polyurethane as a matrix polyurethane. By contrast, polyurethanes with methylene bis (p-cyclohexyl isocyanate)/butanediol hard block showed no contamination during DCA analysis. For this reason, further study of HMDI/BD/PTMO polyurethanes was conducted. HMDI/BD polyurethanes were synthesized with 15-50wt% hard block and a soft block of PTMO-2000 or PTMO-1000 where PTMO-2000 is poly (tetramethylene oxide) with a molecular weight of 2000g/mol and PTMO-1000 has a molecular weight of 1000g/mol. Characterization was performed with FT-IR and 1H NMR spectroscopy to verify polyurethane composition as well as hard block percentage. Thermal characterization was performed with modulated differential scanning calorimetry (MDSC). From MDSC, the glass transition temperatures of the soft and hard block for polyurethanes with PTMO-2000 as the soft block were -80°C and 86°C, respectively. For corresponding polyurethanes containing PTMO-1000 as the soft block, the measured Tgs for the soft and hard segments were -55°C and 65°C, respectively. The disparity between the respective soft and hard segment Tgs of these polyurethanes of differing soft block molecular weights is due to increased phase mixing that causes an increase in soft block Tg and a decrease in hard block Tg for the PTMO-1000 polyurethanes. From dynamic contact angle analyses of HMDI/BD/PTMO polyurethanes, the advancing and receding contact angles gradually decreased with each cycle but approached 80° and 60°, respectively. Results from force-distance curves with flamed glass slides obtained before and after immersion of the polyurethane coatings indicated that no water contamination occurred. Tensile tests demonstrated that hard block percentage, soft block molecular weight, and the amount of chain extender influences mechanical properties. For example, increasing hard block weight percentage increases the modulus. HMDI/BD(30)/PTMO-2000 (PU-1), HMDI/BD(25)/PTMO-2000, (PU-2) and HMDI/BD(35)/PTMO-2000 (PU-10) exhibited the best elastomeric properties. As the final outcome, lack of contamination and good mechanical properties made PU-2 and PU-9 (HMDI/BD(50)/PTMO-1000) suitable candidates as polyurethane matrices for polymer surface modifier evaluation.

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Sjöstrand, Björn. "Evaluation of Compression Testing and Compression Failure Modes of Paperboard : Video analysis of paperboard during short-span compression and the suitability of short- and long-span compression testing of paperboard." Thesis, Karlstads universitet, Institutionen för ingenjörs- och kemivetenskaper (from 2013), 2013. http://urn.kb.se/resolve?urn=urn:nbn:se:kau:diva-27519.

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The objectives of the thesis were to find the mechanisms that govern compression failures in paperboard and to find the link between manufacturing process and paperboard properties. The thesis also investigates two different test methods and evaluates how suitable they are for paperboard grades. The materials are several commercial board grades and a set of hand-formed dynamic sheets that are made to mimic the construction of commercial paperboard. The method consists of mounting a stereomicroscope on a short-span compression tester and recording the compression failure on video, long-span compression testing and standard properties testing. The observed failure modes of paperboard under compression were classified into four categories depending on the appearance of the failures. Initiation of failure takes place where the structure is weakest and fiber buckling happens after the initiation, which consists of breaking of fiber-fiber bonds or fiber wall delamination. The compression strength is correlated to density and operations and raw materials that increase the density also increases the compression strength. Short-span compression and Long-span compression are not suitable for testing all kinds of papers; the clamps in short-span give bulky specimens an initial geometrical shape that can affect the given value of compression strength. Long-span compression is only suitable for a limited range of papers, one problem with too thin papers are low wavelength buckling.

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Auberlet, Delle-Vedove Agnès. "Synthèse et étude structurale de n-benzoyl-n'-phenylurees, insecticides, en vue d'établir une relation entre la structure, la rétention dans des adsorbants modèles et le mode de dégradation. Suivi de recherches sur l'enseignement expérimental de la formulation : étude d'une famille de tensioactifs." Angers, 1995. http://www.theses.fr/1995ANGE0002.

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Dans une première partie, cinq n-benzoyl-n'-phenylurees sont synthétisées, en vue de modéliser leurs interactions avec l’environnement : rétention dans les sols, dégradation. Ces molécules sont des insecticides rémanents agissant par inhibition de la biosynthèse de la chitine. L'analyse d'extraits d'adsorbants modèles traites avec ces molécules est effectuée par chromatographie liquide haute pression en phase inverse. L'étude structurale de ces molécules est réalisée par la combinaison de diverses techniques spectroscopiques : spectrométrie de masse, spectroscopie de rayons X, RMN du proton, du carbone 13, de l'azote 15, spectroscopies U. V. Et infra-rouge, ainsi que par chromatographie sur couche mince, mécanique moléculaire et calcul semi-empirique am1. D'une part nous en déduisons une relation entre la coplaneite du groupe urée et du groupe 4- chlorophényle et la rétention sur adsorbants. D'autre part les indices de liaison, la fragmentation de masse et les études conformationnelle permettent d'interpréter la dégradation du composé, '- difluoré en urée et acide benzoïque tandis que dans les mêmes conditions le composé, '- dichlore est dégradé en benzamide et aniline substituées. Dans une seconde partie, nous présentons un projet didactique d'enseignement expérimental de la formulation, portant sur une famille de tensio-actifs utilisés dans les préparations phytosanitaires : détermination de la concentration micellaire critique, de la H. L. B. , de la température de trouble.

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Hugon, Olivier. "Conception et réalisation d'un transducteur à plasmon de surface en optique intégrée sur verre : application : détecteur de molécules." Grenoble INPG, 1998. http://www.theses.fr/1998INPG0136.

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Des capteurs optiques performants utilisant des plasmons de surface pour la detection de molecules chimiques ou biologiques sont commercialises depuis peu. La prochaine generation sera plus fiable, moins chere et plus facile d'emploi grace a la technologie de l'optique integree. Notre travail a porte sur l'etude, la realisation et la caracterisation d'une structure optique composee d'une fine couche d'argent recouvrant un guide de surface realise par echange d'ions dans un substrat de verre. La forte dependance de la puissance optique de sortie en fonction des caracteristiques optogeometriques (indice et epaisseur) d'une couche dielectrique deposee a la surface du metal en fait un capteur tres sensible. L'etude detaillee des phenomenes de couplage et de propagation des modes au sein de cette structure multimode a conduit a l'elaboration d'un simulateur destine a l'optimisation de ses parametres. Les resultats theoriques obtenus grace aux simulations sont validees par leur confrontation avec des mesures effectuees sur banc optique. Ce travail se termine par une application : la detection de vapeurs de solvants.

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Jones, Christina Michele. "Applications and challenges in mass spectrometry-based untargeted metabolomics." Diss., Georgia Institute of Technology, 2015. http://hdl.handle.net/1853/54830.

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Metabolomics is the methodical scientific study of biochemical processes associated with the metabolome—which comprises the entire collection of metabolites in any biological entity. Metabolome changes occur as a result of modifications in the genome and proteome, and are, therefore, directly related to cellular phenotype. Thus, metabolomic analysis is capable of providing a snapshot of cellular physiology. Untargeted metabolomics is an impartial, all-inclusive approach for detecting as many metabolites as possible without a priori knowledge of their identity. Hence, it is a valuable exploratory tool capable of providing extensive chemical information for discovery and hypothesis-generation regarding biochemical processes. A history of metabolomics and advances in the field corresponding to improved analytical technologies are described in Chapter 1 of this dissertation. Additionally, Chapter 1 introduces the analytical workflows involved in untargeted metabolomics research to provide a foundation for Chapters 2 – 5. Part I of this dissertation which encompasses Chapters 2 – 3 describes the utilization of mass spectrometry (MS)-based untargeted metabolomic analysis to acquire new insight into cancer detection. There is a knowledge deficit regarding the biochemical processes of the origin and proliferative molecular mechanisms of many types of cancer which has also led to a shortage of sensitive and specific biomarkers. Chapter 2 describes the development of an in vitro diagnostic multivariate index assay (IVDMIA) for prostate cancer (PCa) prediction based on ultra performance liquid chromatography-mass spectrometry (UPLC-MS) metabolic profiling of blood serum samples from 64 PCa patients and 50 healthy individuals. A panel of 40 metabolic spectral features was found to be differential with 92.1% sensitivity, 94.3% specificity, and 93.0% accuracy. The performance of the IVDMIA was higher than the prevalent prostate-specific antigen blood test, thus, highlighting that a combination of multiple discriminant features yields higher predictive power for PCa detection than the univariate analysis of a single marker. Chapter 3 describes two approaches that were taken to investigate metabolic patterns for early detection of ovarian cancer (OC). First, Dicer-Pten double knockout (DKO) mice that phenocopy many of the features of metastatic high-grade serous carcinoma (HGSC) observed in women were studied. Using UPLC-MS, serum samples from 14 early-stage tumor DKO mice and 11 controls were analyzed. Iterative multivariate classification selected 18 metabolites that, when considered as a panel, yielded 100% accuracy, sensitivity, and specificity for early-stage HGSC detection. In the second approach, serum metabolic phenotypes of an early-stage OC pilot patient cohort were characterized. Serum samples were collected from 24 early-stage OC patients and 40 healthy women, and subsequently analyzed using UPLC-MS. Multivariate statistical analysis employing support vector machine learning methods and recursive feature elimination selected a panel of metabolites that differentiated between age-matched samples with 100% cross-validated accuracy, sensitivity, and specificity. This small pilot study demonstrated that metabolic phenotypes may be useful for detecting early-stage OC and, thus, supports conducting larger, more comprehensive studies. Many challenges exist in the field of untargeted metabolomics. Part II of this dissertation which encompasses Chapters 4 – 5 focuses on two specific challenges. While metabolomic data may be used to generate hypothesis concerning biological processes, determining causal relationships within metabolic networks with only metabolomic data is impractical. Proteins play major roles in these networks; therefore, pairing metabolomic information with that acquired from proteomics gives a more comprehensive snapshot of perturbations to metabolic pathways. Chapter 4 describes the integration of MS- and NMR-based metabolomics with proteomics analyses to investigate the role of chemically mediated ecological interactions between Karenia brevis and two diatom competitors, Asterionellopsis glacialis and Thalassiosira pseudonana. This integrated systems biology approach showed that K. brevis allelopathy distinctively perturbed the metabolisms of these two competitors. A. glacialis had a more robust metabolic response to K. brevis allelopathy which may be a result of its repeated exposure to K. brevis blooms in the Gulf of Mexico. However, K. brevis allelopathy disrupted energy metabolism and obstructed cellular protection mechanisms including altering cell membrane components, inhibiting osmoregulation, and increasing oxidative stress in T. pseudonana. This work represents the first instance of metabolites and proteins measured simultaneously to understand the effects of allelopathy or in fact any form of competition. Chromatography is traditionally coupled to MS for untargeted metabolomics studies. While coupling chromatography to MS greatly enhances metabolome analysis due to the orthogonality of the techniques, the lengthy analysis times pose challenges for large metabolomics studies. Consequently, there is still a need for developing higher throughput MS approaches. A rapid metabolic fingerprinting method that utilizes a new transmission mode direct analysis in real time (TM-DART) ambient sampling technique is presented in Chapter 5. The optimization of TM-DART parameters directly affecting metabolite desorption and ionization, such as sample position and ionizing gas desorption temperature, was critical in achieving high sensitivity and detecting a broad mass range of metabolites. In terms of reproducibility, TM-DART compared favorably with traditional probe mode DART analysis, with coefficients of variation as low as 16%. TM-DART MS proved to be a powerful analytical technique for rapid metabolome analysis of human blood sera and was adapted for exhaled breath condensate (EBC) analysis. To determine the feasibility of utilizing TM-DART for metabolomics investigations, TM-DART was interfaced with traveling wave ion mobility spectrometry (TWIMS) time-of-flight (TOF) MS for the analysis of EBC samples from cystic fibrosis patients and healthy controls. TM-DART-TWIMS-TOF MS was able to successfully detect cystic fibrosis in this small sample cohort, thereby, demonstrating it can be employed for probing metabolome changes. Finally, in Chapter 6, a perspective on the presented work is provided along with goals on which future studies may focus.

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Книги з теми "Chemical explosive mode analysis"

Cui, Qiang, and Ivet Bahar. Normal Mode Analysis: Theory and Applications to Biological and Chemical Systems. Taylor & Francis Group, 2010.

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Cui, Qiang, and Ivet Bahar. Normal Mode Analysis: Theory and Applications to Biological and Chemical Systems. Taylor & Francis Group, 2005.

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Cui, Qiang, and Ivet Bahar. Normal Mode Analysis: Theory and Applications to Biological and Chemical Systems. Taylor & Francis Group, 2005.

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Bui, Lan Nang. Application of neural network analysis to the thickness-shear mode chemical sensor. Dept of Chemistry, U of Toronto, 1998.

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(Editor), Qiang Cui, and Ivet Bahar (Editor), eds. Normal Mode Analysis: Theory and Applications to Biological and Chemical Systems (Mathematical and Computational Biology). Chapman & Hall/CRC, 2005.

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Numerical Modeling of Explosives and Propellants. 3rd ed. CRC, 2007.

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Частини книг з теми "Chemical explosive mode analysis"

Yoo, Chun Sang, Tianfeng Lu, and Jacqueline H. Chen. "Chemical Explosive Mode Analysis for Diagnostics of Direct Numerical Simulations." In Data Analysis for Direct Numerical Simulations of Turbulent Combustion, 89–108. Cham: Springer International Publishing, 2020. http://dx.doi.org/10.1007/978-3-030-44718-2_5.

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Basov, Nikolay G., Anatoly S. Bashkin, Valery I. Igoshin, Anatoly N. Oraevsky, and Vladimir A. Shcheglov. "Kinetics and Numerical Analysis of Chain-Reaction Chemical Lasers (Pulsed Mode)." In Chemical Lasers, 107–65. Berlin, Heidelberg: Springer Berlin Heidelberg, 1990. http://dx.doi.org/10.1007/978-3-642-70961-6_3.

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Bull, John W., and C. H. Woodford. "The numerical analysis and modelling of repaired runways following chemical explosive crater formation." In Numerical Analysis and Modelling of Composite Materials, 128–51. Dordrecht: Springer Netherlands, 1996. http://dx.doi.org/10.1007/978-94-011-0603-0_6.

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Tavan, Paul. "Quantum Chemical Normal Mode Analysis for Interpretation of Vibrational Spectra of Biomolecules: State of the Art." In Spectroscopy of Biological Molecules, 3–6. Dordrecht: Springer Netherlands, 1995. http://dx.doi.org/10.1007/978-94-011-0371-8_1.

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Bell, Michael J., Michael L. Thompson, and Philip W. Moody. "Using Soil Tests to Evaluate Plant Availability of Potassium in Soils." In Improving Potassium Recommendations for Agricultural Crops, 191–218. Cham: Springer International Publishing, 2020. http://dx.doi.org/10.1007/978-3-030-59197-7_8.

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AbstractThe purpose of this chapter is to describe how bioavailable soil K is assessed or predicted by soil tests. Soil testing commonly refers to the collection of a sample of soil representative of a field or agronomic management unit and, by way of extraction using chemical reagents, determination of the quantity of a nutrient that can be related to plant uptake or yield. Normally only a small fraction of the total quantity of the nutrient present in the soil is extracted during the procedure, but if that amount can be correlated with actual crop uptake or overall crop productivity, then the soil test is deemed to have useful predictive power.Soil tests are routinely used to guide applications of fertilizer to soil so that crop demand for nutrients can be met effectively and economically. Here, we summarize the procedures involved in collecting a representative soil sample for K analysis, outline how that sample should be prepared for laboratory analysis, highlight the principles and mode of action of routine soil tests, and explore some common issues that may confound the correlation between a soil K test result and plant K acquisition or crop yield. Soil testing methods are discussed in the context of their relationship to the different forms of soil K and the in-soil chemical processes that may change these forms into K that can be taken up by roots.

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Albright, Richard D. "Ordnance Detection and Analysis." In Cleanup of Chemical and Explosive Munitions, 89–103. Elsevier, 2008. http://dx.doi.org/10.1016/b978-081551540-1.50012-6.

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Albright, Richard D. "Ordnance Detection and Analysis." In Cleanup of Chemical and Explosive Munitions, 99–111. Elsevier, 2012. http://dx.doi.org/10.1016/b978-1-4377-3477-5.00007-6.

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Griep, Mark A., and Marjorie L. Mikasen. "Chem 101: Learning by Doing." In ReAction! Oxford University Press, 2009. http://dx.doi.org/10.1093/oso/9780195326925.003.0012.

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This chapter stands at the midpoint of the “bright side” of this book. Its oppositional partner on the “dark side” is chapter 3 on chemical arsenals. Thus, education and war making present a core contrast in the uses of chemical knowledge in the movies. We have only to think of the closed world of Dr. Mabuse, symbolized so well by the writings in his notebook, as described in chapter 3. His inward, secret scribblings speak of outward, villainous purposes. In juxtaposition, the writing on the blackboards of this chapter’s movies is exposed; it is to be seen. This writing represents the open, cool, dispassionate transmission of facts in symbolic chemical language. But a little something more has slipped through in this section’s movie example. When we read its blackboard, we see the explosive nature of knowledge itself. “You have to see and read a movie at the same time,” says Harvard professor Tom Conley, whose creative film analyses leave readers with an appreciation of just how rich cinematic art can be (Savisky 2006). In his book Film Hieroglyphs, Conley considers writing as it appears in movies. He shows it is often an incidental and uncontrollable element that inserts itself into our movie-watching experience, leaving us to ponder nonnarrative written material observed on the movie sets. Conley calls the points where story, image, and writing are at odds with one another “ruptures.” Graphically interrupting the flow of the moving image, these points provide “slide areas” for analysis and new insights (Conley 1991). This section examines chemical notations appearing in our movie examples, and how they provide opportunities for an enhanced reading of these movies. The blackboard in The Affairs of Dobie Gillis (1953), a musical campus comedy, ruptures the movie like no other blackboard in movie history. But first, let us set the scene. Pansy Hammer (Debbie Reynolds) attends Grainbelt University to “work, work, work.” As she and her lab mates begin their first laboratory exercise, she gleefully tells them she really likes chemistry. After a few moments, the professor announces, “Don’t let the bubbles come too fast” and then Hammer’s experiment explodes.

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Nejad, Hadis Z., and Reza Samizadeh. "Decision Support Model for Fire Insurance Risk Analysis in a Petrochemical Case Study." In Transportation Systems and Engineering, 990–1004. IGI Global, 2015. http://dx.doi.org/10.4018/978-1-4666-8473-7.ch050.

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A decision support system was researched and applied to a case study in the petrochemical industry. The participants were an insurance company underwriting the policies of oil and gas refineries located in a major oil producing nation. The Chemical Process Quantitative Risk Analysis methodology was applied as a framework to implement uncertainty quantification and risk analysis using a specialized commercial DSS software product. A gas vapor explosion was simulated at an oil refinery, to predict the fire and radiation damage. Costs and risks were entered into the model based on historical data. Loss estimates were generated for equipment and buildings located various distances (pressures) from the explosion origin. Overall, the DSS model predicted an expected loss of over $14,000,000 USD for equipment located in the 50 meter explosion radius, which represented a loss ratio of almost 52%. The losses predicted from the DSS model were comparable to the literature and to experiences of the case study company. The margin of error from the DSS model was less than ±5% which made it very reliable according to benchmarks.

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Mihoub, Mohamed, Ahmed Said, and Ridha Ben. "Multimodel Discrete Second Order Sliding Mode Control: Stability Analysis and Real Time Application on a Chemical Reactor." In Sliding Mode Control. InTech, 2011. http://dx.doi.org/10.5772/15828.

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Тези доповідей конференцій з теми "Chemical explosive mode analysis"

Towery, Colin A., Peter E. Hamlington, Xinyu Zhao, Chao Xu, Tianfeng Lu, and Alexei Poludnenko. "Lagrangian Chemical Explosive Mode Analysis of Highly Turbulent Premixed Flames." In AIAA Scitech 2019 Forum. Reston, Virginia: American Institute of Aeronautics and Astronautics, 2019. http://dx.doi.org/10.2514/6.2019-1643.

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Zhou, Dezhi, Hongyuan Zhang, and Suo Yang. "Computational Diagnostics for Reacting Flows with Global Pathway Analysis Aided by Chemical Explosive Mode Analysis." In AIAA Scitech 2021 Forum. Reston, Virginia: American Institute of Aeronautics and Astronautics, 2021. http://dx.doi.org/10.2514/6.2021-1368.

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Wemhoff, Aaron P., Richard Becker, and Alan K. Burnham. "Calibration of Chemical Kinetic Models Using Simulations of Small-Scale Cookoff Experiments." In ASME 2008 Heat Transfer Summer Conference collocated with the Fluids Engineering, Energy Sustainability, and 3rd Energy Nanotechnology Conferences. ASMEDC, 2008. http://dx.doi.org/10.1115/ht2008-56108.

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Establishing safe handling limits for explosives in elevated temperature environments is a difficult problem that often requires extensive simulation. The largest influence on predicting thermal cookoff safety lies in the chemical kinetic model used in these simulations, and these kinetic model reaction sequences often contain multiple steps. Several small-scale cookoff experiments, notably Differential Scanning Calorimetry (DSC), Thermogravimetric Analysis (TGA), One-Dimensional Time-to-Explosion (ODTX), and the Scaled Thermal Explosion (STEX) have been performed on various explosives to aid in cookoff behavior determination. Past work has used a single test from this group to create a cookoff model, which does not guarantee agreement with the other experiments. In this study, we update the kinetic parameters of an existing model for the common explosive 2,4,6-Trinitrotoluene (TNT) using DSC and ODTX experimental data at the same time by minimizing a global Figure of Merit based on hydrodynamic simulated data. We then show that the new kinetic model maintains STEX agreement, reduces DSC agreement, and improves ODTX and TGA agreement when compared to the original model. In addition, we describe a means to use implicit hydrodynamic simulations of DSC experiments to develop a reaction model for TNT melting.

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King, Kim W., and Johnny H. Waclawczyk. "Blast Containment Chamber Development and Testing." In ASME 2006 Pressure Vessels and Piping/ICPVT-11 Conference. ASMEDC, 2006. http://dx.doi.org/10.1115/pvp2006-icpvt-11-93028.

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Explosive containment chambers are produced for a number of purposes. Some chambers are designed to protect personnel from a single accidental explosion, such as storage in a manufacturing process. Other chambers are designed for multiple intended detonations such as a chamber used for explosive research and testing. Several bomb containment vessels are produced that are used for explosives storage and transportation, as well as the destruction of conventional and chemical-biological improvised explosive devices (IED). Multiple spherical vessels exist that are rated for multiple detonations of explosives that range from 10-lbs TNT equivalent to more than 25-lbs TNT in what would be considered a venting mode of operation. Additionally, there are similar chambers designed to limit the risk of exposure to hazardous materials during the transportation and destruction of an IED that has an associated chemical or biological hazard. The charge rating for these chambers is typically less due to the nature of the threat. A new type of bomb containment vessel has emerged to contain the effects of a device found in luggage or smaller shipping packages. These chambers are typically intended to contain IEDs that do not have an associated chemical or biological hazard. Often times these units do not have the preferred geometrical shape of a sphere because of use and spatial restrictions. Additionally, these units are designed for a single detonation of the design charge weight (i.e., it is not reusable). It is expected to undergo severe permanent displacement during an event, but will not rupture. Other explosive containment chambers are used to destroy military munitions. Many of these chambers have survived hundreds or even thousands or detonations. Typically, these chambers are designed using a dynamic non-linear finite element analysis (FEA) during initial design. Following the design phase, these vessels are tested to confirm performance, and (in the case of a sealed chamber) characterize the leakage characteristics. Additionally, the test program is intended to identify and eliminate any physical weaknesses in the system, quantify structural response of the system under various explosive charge weights, and identify operational and maintenance problems. This paper describes the design and testing procedures for these programs and compares them based on similarities and differences.

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Yip, Mien, Brent Haroldsen, and Joe Puskar. "Code Case Validation of Impulsively Loaded EDS Subscale Vessel." In ASME 2008 Pressure Vessels and Piping Conference. ASMEDC, 2008. http://dx.doi.org/10.1115/pvp2008-61381.

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The Explosive Destruction System (EDS) was developed by Sandia National Laboratories for the US Army Product Manager for Non-Stockpile Chemical Materiel (PMNSCM) to destroy recovered, explosively configured, chemical munitions. PMNSCM currently has five EDS units that have processed over 850 items. The system uses linear and conical shaped charges to open munitions and attack the burster followed by chemical treatment of the agent. The main component of the EDS is a stainless steel, cylindrical vessel, which contains the explosion and the subsequent chemical treatment. Extensive modeling and testing have been, and continue to be used, to design and qualify the vessel for different applications and conditions. This has included explosive overtests using small, geometrically scaled vessels to study overloads, plastic deformation, and failure limits. Recently the ASME Task Group on Impulsively Loaded Vessels has developed a Code Case under Section VIII Division 3 of the ASME Boiler and Pressure Vessel Code for the design of vessel like the EDS. In this article, a representative EDS subscale vessel is investigated against the ASME Design Codes for vessels subjected to impulsive loads. Topics include strain-based plastic collapse, fatigue and fracture analysis, and leak-before-burst. Vessel design validation is based on model results, where the high explosive (HE) pressure histories and subsequent vessel response (strain histories) are modeled using the analysis codes CTH and LS-DYNA, respectively.

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Jella, Sandeep, Gilles Bourque, Pierre Gauthier, Philippe Versailles, Jeffrey Bergthorson, Ji-Woong Park, Tianfeng Lu, Snehashish Panigrahy, and Henry Curran. "Analysis of Autoignition Chemistry in Aeroderivative Premixers at Engine Conditions." In ASME Turbo Expo 2020: Turbomachinery Technical Conference and Exposition. American Society of Mechanical Engineers, 2020. http://dx.doi.org/10.1115/gt2020-15697.

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Abstract The minimization of autoignition risk is critical to the design of premixers of high power aeroderivative gas turbines as an increased use of highly reactive future fuels (for example, hydrogen or higher hydrocarbons) is anticipated. Safety factors based on ignition delays of homogeneous mixtures, are generally used to guide the choice of a residence time for a given premixer. However, autoignition chemistry at aeroderivative conditions is fast (0.5–2 milliseconds) and can be initiated within typical premixer residence times. The analysis of what takes place in this short period necessarily involves the study of low-temperature autoignition precursor chemistry, but precursors can change with fuel and local reactivity. Chemical Explosive Modes are a natural alternative to study this as they can provide a measure of autoignition risk by considering the whole thermochemical state in the framework of an eigenvalue problem. When transport effects are included by coupling the evolution of the Chemical Explosive Modes to turbulence, it is possible to obtain a measure of spatial autoignition risk where both chemical (e.g. ignition delay) and aerodynamic (e.g. local residence time) influences are unified. In this article, we describe a method that couples Large Eddy Simulation to newly developed, reduced autoignition chemical kinetics to study autoignition precursors in an example pre-mixer representative of real life geometric complexity. A blend of pure methane and dimethyl ether (DME), a common fuel used for experimental autoignition studies, was transported using the reduced mechanism (38 species / 238 reactions) at engine conditions at increasing levels of DME concentration until exothermic autoignition kernels were formed. The resolution of species profiles was ensured by using a thickened flame model where dynamic thickening was carried out with a flame sensor modified to work with multi-stage heat release. The paper is outlined as follows: First, a reduced mechanism is constructed and validated for modeling methane as well as di-methyl ether (DME) autoignition. Second, sensitivity analysis is used to show the need for Chemical Explosive Modes. Third, the thickened flame model modifications are described and then applied to an example premixer at 25 bar / 890K preheat. The Chemical Explosive Mode analysis closely follows the large thermochemical changes in the premixer as a function of DME concentration and identifies where the premixer is sensitive and flame anchoring is likely to occur.

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Pal, Pinaki, Chao Xu, Gaurav Kumar, Scott A. Drennan, Brent A. Rankin, and Sibendu Som. "Large-Eddy Simulation and Chemical Explosive Mode Analysis of Non-Ideal Combustion in a Non-Premixed Rotating Detonation Engine." In AIAA Scitech 2020 Forum. Reston, Virginia: American Institute of Aeronautics and Astronautics, 2020. http://dx.doi.org/10.2514/6.2020-2161.

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Yip, Mien, and Brent Haroldsen. "Life Assessment of Full-Scale EDS Vessel Under Impulsive Loadings." In ASME 2010 Pressure Vessels and Piping Division/K-PVP Conference. ASMEDC, 2010. http://dx.doi.org/10.1115/pvp2010-26036.

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The Explosive Destruction System (EDS) was developed by Sandia National Laboratories for the US Army Product Manager for Non-Stockpile Chemical Materiel (PMNSCM) to destroy recovered, explosively configured, chemical munitions. PMNSCM currently has five EDS units that have processed over 1,400 items. The system uses linear and conical shaped charges to open munitions and attack the burster followed by chemical treatment of the agent. The main component of the EDS is a stainless steel, cylindrical vessel, which contains the explosion and the subsequent chemical treatment. Extensive modeling and testing have been used to design and qualify the vessel for different applications and conditions. The high explosive (HE) pressure histories and subsequent vessel response (strain histories) are modeled using the analysis codes CTH and LS-DYNA, respectively. Using the model results, a load rating for the EDS is determined based on design guidance provided in the ASME Code, Sect. VIII, Div. 3, Code Case No. 2564. One of the goals is to assess and understand the vessel’s capacity in containing a wide variety of detonation sequences at various load levels. Of particular interest are to know the total number of detonation events at the rated load that can be processed inside each vessel, and a maximum load (such as that arising from an upset condition) that can be contained without causing catastrophic failure of the vessel. This paper will discuss application of Code Case 2564 to the stainless steel EDS vessels, including a fatigue analysis using a J-R curve, vessel response to extreme upset loads, and the effects of strain hardening from successive events.

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LIU, RUI, TIANCHU WANG, GE KANG, ZHENG YANG, ZHONGBIN ZHOU, and PENGWAN CHEN. "DAMAGE FAILURE AND SAFETY OF POLYMER BONDED EXPLOSIVE CHARGES UNDER IMPACT LOADING." In 32ND INTERNATIONAL SYMPOSIUM ON BALLISTICS. Destech Publications, Inc., 2022. http://dx.doi.org/10.12783/ballistics22/36071.

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As energetic composite materials, polymer bonded explosives (PBX) are composed of highly filled explosive crystals and a small of polymer binder. Accidental explosion could occur under low velocity impact. The ignition mechanism has drawn great attention to scientists and engineers. Hotspot is considered to induce the occurrence of ignition. Our works focus on the relation between the microcrack evolution and hotspot formation. The deformation, damage and failure behavior of PBX was investigated by split Hopkinson pressure bar, gas gun impact and penetration. In these dynamic loading experiments, the microstructure of the recovered specimens was analyzed by scanning electron microscope. It reveals that the cracking along the interface between the explosive crystal and the polymer binder under the tension, while the intergranular fracture is the main mode under the compression. The numerical manifold method was developed to simulate the tension and compression behavior. The effect of the initial defect, the strain rate and temperature on the tension and compression behavior was analyzed. The fracture modes of the tension and compression match the dynamic experiments above well. The low impact ignition analysis was conducted by means of Steven impact test. The specimen size effect on the ignition was mainly focused. The ignition observation and ignition delay time were measured. Also, the ignition velocity and reaction level were discussed. In addition, based on Visco-SCRAM model, a mechanical-thermal-chemical coupling model was developed to understand the ignition behavior in Steven impact test. The effect of the impact velocity on the ignition was analyzed. The mechanism of the size effect on ignition was discussed. Different projectile shapes were designed to act on the specimen. The difference of the ignition among these projectiles was compared. Further, the model was applied to simulate the multi impact corresponding to the real application scenarios. Moreover, in order to refine the microcrack evolution, the tension-compression asymmetrical microcrack evolution was proposed. The stochastic distribution of the microcrack length and density produced the ignition uncertainty, and further based on the Monte Carlo method, the ignition probability was quantified. These simulations matched the experimental results well.

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Yiren, Lian, Sun Hongchao, Chen Lei, Meng Dongyuan, Li Guoqiang, Zhuang Dajie, Sun Shutang, and Zhang Jiangang. "Review and Security Assessment of Red Oil Explosions in Evaporator." In 2018 26th International Conference on Nuclear Engineering. American Society of Mechanical Engineers, 2018. http://dx.doi.org/10.1115/icone26-82221.

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Purex progress is widely applied in the nuclear fuel reprocessing plants all over the world. However, various security problems occur in reprocessing facility involving the intense attention of red oil explosion. The exothermic reactions among TBP, nitric salts and nitric acid were responsible for the red oil explosion. In this paper, explosion events at nuclear fuel reprocessing plants initiated by red oil phenomena were reviewed. The formation and reaction mechanisms of red oil causing explosions were analyzed. Moreover, the evaluation and analysis model was built up to evaluate the security assessment of red oil explosion from the associated calculations of data in the typical red oil explosive accidents and the results of subsequent laboratory studies on the chemical reaction.

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Звіти організацій з теми "Chemical explosive mode analysis"

Glasscott, Matthew, Johanna Jernberg, Erik Alberts, and Lee Moores. Toward the electrochemical detection of 2,4-dinitroanisole (DNAN) and pentaerythritol tetranitrate (PETN). Engineer Research and Development Center (U.S.), March 2022. http://dx.doi.org/10.21079/11681/43826.

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Analytical methods to rapidly detect explosive compounds with high precision are paramount for applications ranging from national security to environmental remediation. This report demonstrates two proof-of-concept electroanalytical methods for the quantification of 2,4-dinitroanisol (DNAN) and pentaerythritol tetranitrate (PETN). For the first time, DNAN reduction was analyzed and compared at a bare graphitic carbon electrode, a polyaniline-modified (PANI) electrode, and a molecularly imprinted polymer (MIP) electrode utilizing PANI to explore the effect of surface-area and preconcentration affinity on the analytical response. Since some explosive compounds such as PETN are not appreciably soluble in water (<10 μg/L), necessitating a different solvent system to permit direct detection via electrochemical reduction. A 1,2-dichloroethane system was explored as a possibility by generating a liquid-liquid extraction-based sensor exploiting the immiscibility of 1,2-dichloroethane and water. The reduction process was explored using a scan rate analysis to extract a diffusion coefficient of 6.67 x 10⁻⁶ cm/s, in agreement with literature values for similarly structured nitrate esters. Once further refined, these techniques may be extended to other explosives and combined with portable electrochemical hardware to bring real-time chemical information to soldiers and citizens alike.

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Gurevitz, Michael, William A. Catterall, and Dalia Gordon. Learning from Nature How to Design Anti-insect Selective Pesticides - Clarification of the Interacting Face between Insecticidal Toxins and their Na-channel Receptors. United States Department of Agriculture, January 2010. http://dx.doi.org/10.32747/2010.7697101.bard.

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Structural details on the interacting faces of toxins and sodium channels (Navs), and particularly identification of elements that confer specificity for insects, are difficult to approach and require suitable experimental systems. Therefore, natural toxins capable of differential recognition of insect and mammalian Navs are valuable leads for design of selective compounds in insect control. We have characterized several scorpion toxins that vary in preference for insect and mammalian Navs, and identified residues important for their action. However, despite many efforts worldwide, only little is known about the receptor sites of these toxins, and particularly on differences between these sites on insect and mammalian Navs. Another problem arises from the massive overuse of chemical insecticides, which increases resistance buildup among various insect pests. A possible solution to this problem is to combine different insecticidal compounds, especially those that provide synergic effects. Our recent finding that combinations of insecticidal receptor site-3 toxins (sea anemone and scorpion alpha) with scorpion beta toxins or their truncated derivatives are synergic in toxicity to insects is therefore timely and strongly supports this approach. Our ability to produce toxins and various Navs in recombinant forms, enable thorough analysis and structural manipulations of both toxins and receptors. On this basis we propose to (1) restrict by mutagenesis the activity of insecticidal scorpion -toxins and sea anemone toxins to insects, and clarify the molecular basis of their synergic toxicity with antiinsect selective -toxins; (2) identify Nav elements that interact with scorpion alpha and sea anemone toxins and those that determine toxin selectivity to insects; (3) determine toxin-channel pairwise side-chain interactions by thermodynamic mutant cycle analysis using our large collection of mutant -toxins and Nav mutants identified in aim 2; (4) clarify the mode of interaction of truncated -toxins with insect Navs, and elucidate how they enhance the activity of insecticidal site-3 toxins. This research may lead to rational design of novel anti-insect peptidomimetics with minimal impact on human health and the environment, and will establish the grounds for a new strategy in insect pest control, whereby a combination of allosterically interacting compounds increase insecticidal action and reduce risks of resistance buildup.

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Sessa, Guido, and Gregory Martin. A functional genomics approach to dissect resistance of tomato to bacterial spot disease. United States Department of Agriculture, January 2004. http://dx.doi.org/10.32747/2004.7695876.bard.

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The research problem. Bacterial spot disease in tomato is of great economic importance worldwide and it is particularly severe in warm and moist areas affecting yield and quality of tomato fruits. Causal agent of spot disease is the Gram-negative bacterium Xanthomonas campestris pv. vesicatoria (Xcv), which can be a contaminant on tomato seeds, or survive in plant debris and in association with certain weeds. Despite the economic significance of spot disease, plant protection against Xcvby cultural practices and chemical control have so far proven unsuccessful. In addition, breeding for resistance to bacterial spot in tomato has been undermined by the genetic complexity of the available sources of resistance and by the multiple races of the pathogen. Genetic resistance to specific Xcvraces have been identified in tomato lines that develop a hypersensitive response and additional defense responses upon bacterial challenge. Central goals of this research were: 1. To identify plant genes involved in signaling and defense responses that result in the onset of resistance. 2. To characterize molecular properties and mode of action of bacterial proteins, which function as avirulence or virulence factors during the interaction between Xcvand resistant or susceptible tomato plants, respectively. Our main achievements during this research program are in three major areas: 1. Identification of differentially expressed genes during the resistance response of tomato to Xcvrace T3. A combination of suppression subtractive hybridization and microarray analysis identified a large set of tomato genes that are induced or repressed during the response of resistant plants to avirulent XcvT3 bacteria. These genes were grouped in clusters based on coordinate expression kinetics, and classified into over 20 functional classes. Among them we identified genes that are directly modulated by expression of the type III effector protein AvrXv3 and genes that are induced also during the tomato resistance response to Pseudomonas syringae pv. tomato. 2. Characterization of molecular and biochemical properties of the tomato LeMPK3MAP kinase. A detailed molecular and biochemical analysis was performed for LeMPK3 MAP kinase, which was among the genes induced by XcvT3 in resistant tomato plants. LeMPK3 was induced at the mRNA level by different pathogens, elicitors, and wounding, but not by defense-related plant hormones. Moreover, an induction of LeMPK3 kinase activity was observed in resistant tomato plants upon Xcvinfection. LeMPK3 was biochemically defined as a dual-specificity MAP kinase, and extensively characterized in vitro in terms of kinase activity, sites and mechanism of autophosphorylation, divalent cation preference, Kₘand Vₘₐₓ values for ATP. 3. Characteriztion of molecular properties of the Xcveffector protein AvrRxv. The avirulence gene avrRxvis involved in the genetic interaction that determines tomato resistance to Xcvrace T1. We found that AvrRxv functions inside the plant cell, localizes to the cytoplasm, and is sufficient to confer avirulence to virulent Xcvstrains. In addition, we showed that the AvrRxv cysteine protease catalytic core is essential for host recognition. Finally, insights into cellular processes activated by AvrRxv expression in resistant plants were obtained by microarray analysis of 8,600 tomato genes. Scientific and agricultural significance: The findings of these activities depict a comprehensive and detailed picture of cellular processes taking place during the onset of tomato resistance to Xcv. In this research, a large pool of genes, which may be involved in the control and execution of plant defense responses, was identified and the stage is set for the dissection of signaling pathways specifically triggered by Xcv.

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