The Nkout (Cameroon) and Putu (Liberia) oxide facies iron ore deposits comprise fresh magnetite banded iron formation (BIF) at depth, which weathers towards the surface, forming high grade martite–goethite ores. This study aimed to improve the mineralogical understanding of these deposits in order to predict their metallurgical responses. It concentrated on developing the QEMSCAN® technique and testing its application to these ore types, but also used a variety of other analysis methods. The QEMSCAN® species identification protocol was developed to include three goethite entries: goethite/limonite, phosphorus-bearing and aluminium-bearing goethite. QEMSCAN® was also used to distinguish between the iron oxides using their backscattered electron signals. To test the correlation between the mineralogy and metallurgical characteristics, magnetic separations were carried out. The samples were divided into 4 main groups based on their whole rock Fe content, determined by XRF analysis, and their degree of weathering: enriched material, weathered magnetite itabirite, transitional magnetite itabirite and magnetite itabirite. Quartz and Al oxide and hydroxide minerals such as gibbsite are the major gangue minerals in the magnetite BIF and martite–goethite ores respectively. From the QEMSCAN® analysis it was concluded that the iron oxides are closely associated and liberation of them individually is poor. Liberation increases when they are grouped together as iron oxide. Chamosite concentrations > 6 wt. % significantly lower liberation of the iron oxides. From the metallurgical testing, it was concluded that iron oxide modal mineralogy gives an indication of iron recovery but other QEMSCAN® data such as mineral association and liberation could be important especially if the iron oxide minerals are not liberated. Grain size and instrument characteristics also affect recovery of iron minerals. There is no evidence to show that there is any structural control on the BIF mineralisation at Nkout because metamorphism has significantly affected the lithological characteristics. The BIF mineralised zones occur as stacks with no particular stratigraphic relationship. Alteration and stratigraphy are the main controls on the martite–goethite ores. These results are applicable to most other BIFs so that as direct shipping ores are exhausted, the approach used here can help to develop the lower grade portions of the deposits.

Hepatitis A virus (HAV) is a non-enveloped, positively charged single stranded RNA hepatotropic agent from the family Picornaviridae, and the sole member of the genus Hepatovirus. There is only one HAV serotype but there are seven genotypes. Hepatitis A (HA) infection is usually self-limiting and the severity of the illness is age dependant. In children, infection with HAV is usually asymptomatic, while most adults and immunocompromised patients develop moderate to severe clinical disease. HA is endemic in South Africa (SA) with 100% of children from the lower socio-economic population acquiring immunity before the age of 10. With the current trends in urbanisation, a change in the epidemic vulnerability of the SA population can be expected. HAV is predominantly transmitted by the faecal-oral route and contaminated food and water are important sources of infection. However, the contribution of waterborne HAV to the burden of HA disease in SA is unknown. The aims of this investigation were to assess techniques for the recovery, isolation and detection of HAV from water sources. Thereafter these techniques were applied to estimate the potential risk of infection posed to communities using the water sources for recreational and domestic purposes. This would elucidate whether or not water plays a role in the spread of HAV infection in SA. An effective and sensitive concentration method is fundamental to the successful detection of HAV in water sources. Three primary recovery and two secondary concentration techniques were investigated in this study. An in-house modified glass wool technique, using 15g of glass wool and with the addition of three metal gauze grids at 5g intervals, proved to be the most sufficient and cost effective technique for the primary recovery of HAV from water sources. The packing density of the glass wool and positioning of the grids proved to be essential for efficient HAV recovery. A polyethylene glycol/sodium chloride secondary concentration technique proved to be more cost effective than commercial centrifugal devices. Combinations of cell cultures, propagation conditions, RNA extraction protocols and detection techniques were assessed for the isolation and detection of HAV. A combination of FRhK-4R cell culture propagation and reverse transcription-polymerase chain reaction-oligonucleotide probe assay was demonstrated to be the simple, most efficient technique for the detection of HAV. The nucleotide sequences of HAV strains from water sources and clinical specimens were compared to ascertain whether the strains from water were a potential source of infection. Although the majority of clinical strains clustered seperately from the water strains, one strain from an asymptomatic patient was identical to a number of strains from water. This suggests that HAV in the environment is a potential source of infection in SA. To assess the potential risk of infection constituted by HAV to persons using surface dam and river water for domestic and recreational purposes, a deterministic exponential risk assessment model which works with mean values and conservative assumptions was applied. Results indicated a minimal risk of infection to the higher socio-economic, non-immune population using the water for recreational purposes, if 100 ml of water was ingested per day. No risk was identified for the lower socio-economic, predominantly immune, population who uses the same water sources for domestic and drinking purposes. This study represents the first comprehensive data on risk of infection constituted by waterborne HAV in SA. / Dissertation (MSc)--University of Pretoria, 2008. / Medical Virology / unrestricted

L'Electrogravimetria AC empra una microbalança de quars electroquímica (EQCM) en règim dinàmic. En l'EQCM un dels elèctrodes d'or depositats sobre el cristall és recobert amb una fina pelolícula d'un polímer electroactiv i és emprat com a elèctrode de treball (WE) dins d'una celola electroquímica. Les variacions de la freqüència de ressonància de la microbalança de quars (QCM) permeten obtindre la resposta massa associada amb la transferència de càrrega que es dóna en la interfície polímer-electròlit. L'Electrogravimetria AC va ser proposta a fi de caracteritzar i separadament identificar el moviment dels ions i el solvent en la interfície polímer-electròlit. En esta tècnica s'analitza en el domine de la freqüència la resposta de massa davant de xicotetes pertorbacions de voltatge gràcies a l'ocupació de la microbalança de quars en règim dinàmic. Per a este propòsit s'aplica una xicoteta pertorbació sinusoidal superposada a una tensió contínua, entre l'elèctrode de referència i l'elèctrode de treball de la celola. Posteriorment, es pot dibuixar la funció de transferència electrogravimètrica (EGTF), definida esta com la raó (?m/?E) entre l'amplitud dels canvis de massa induïts (?m) i l'amplitud de la pertorbació sinusoïdal aplicada (?E). Esta funció de transferència se dibuixa en un pla complex per a cada una de les freqüències de la senyal de pertorbació. Les distintes espècies iònicas involucrades són identificades en el pla complex per mitjà de bucles característics sempre que els bucles no se superposen. Per mitjà d'esta tesi doctoral es proposa un nou sistema de conversió de freqüència-tensió basat en un doble ajust de freqüència implementat amb un PLL mesclant elements analògics i digitals (AD PLL). Els resultats trobats tant en la caracterització electrònica del dispositiu com en la fase experimental proven la fiabilitat del sistema per als mesuraments realitzats en la tècnica d'Electrogravimetria AC. / Torres Villa, RA. (2007). Instrumental techniques for improving the measurements based on Quartz Crystal Microbalances (Técnicas instrumentales para mejorar las mediciones con microbalanzas de cuarzo) [Tesis doctoral no publicada]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/17323 / Palancia

<p>U ovom radu vr&scaron;ena je izolacija sojeva<em>&nbsp; P. shigelloides</em>&nbsp; iz uzoraka povr&scaron;inskih voda<br />Panonske nizije i formirana je kolekcija kultura, nakon čega je obavljena karakterizacija<br />faktora virulencije i antibiotske rezistencije&nbsp; izolovanih sojeva. Pored toga vr&scaron;ena je<br />izolacija bakteriofaga specifičnih za vrstu <em>P. shigelloides</em> iz uzoraka povr&scaron;inskih i otpadnih voda kao i njihova karakterizacija. Karakterizacija je podrazumevala sledeće testove: ispitivanje efikasnosti lize, litičkog spektra, uticaja različitih ekolo&scaron;kih faktora,<br />određivanje proteinskog profila i karakterizaciju genoma. Pored toga, vr&scaron;ena je detekcija<br />izolovanih bakteriofaga kori&scaron;ćenjem protočnog citometra. Rezultati ovog rada su potvrdili<br />prisustvo bakterije <em>P. shigelloides</em>&nbsp; i njenih specifičnih bakteriofaga u povr&scaron;inskim&nbsp; vodama Panonske nizije. Budući da su bakteriofagi specifični za vrstu&nbsp;<em> P. shigelloides&nbsp;</em> po prvi put izolovani, rezultati ovog rada mogu predstavljajati prvi&nbsp; korak u ispitivanjima vezanim za regulaciju brojnosti ove bakterije putem primene bakteriofaga.</p> / <p>We analyzed surface waters collected in Panonian plane, for the presence of bacterium&nbsp; <em>P. shigelloides</em>. The bacterial strains were preserved and characterized for virulence factors and antibiotic resistance. In addition, isolation of&nbsp; <em>P. shigelloides</em>&nbsp; specific bacteriophages was performed. Characterization of isolated phages included the following tests: examination of lytic efficacy, lytic spectrum, the influence of various ecological factors, the determination of the protein profile and the characterization of the genome. In addition, isolated bacteriophages were detected using a flow cytometer. The results of this paper demonstrate that the surface waters of Panonian plane contain bacterium&nbsp; <em>P. shigelloides&nbsp;</em> and its specific bacteriophages. Since&nbsp; <em>P. shigelloides</em>&nbsp; &ndash;&nbsp; specific bacteriophages are for the&nbsp;first time isolated, the results of this paper can represent the first step in the studies related to the regulation of the number of this bacterium by the application of bacteriophages.</p>

O filtro cuno faz parte do circuito de tratamento de água do reator IEA-R1 que , quando saturado, é substituído, se tornando um rejeito radioativo que deve ser gerenciado. Neste trabalho foi realizada a caracterização primária do filtro cuno do reator nuclear IEA-R1 do IPEN utilizando-se espectrometria gama associada ao método de Monte Carlo. A espectrometria gama foi realizada utilizando-se um detector de germânio hiperpuro (HPGe). O cristal de germânio representa o volume ativo de detecção do detector HPGe, que possui uma região denominada camada morta ou camada inativa. Na literatura tem sido reportada uma diferença entre os valores experimentais e teóricos na obtenção da curva de eficiência desses detectores. Neste trabalho foi utilizado o código MCNP-4C para a obtenção da calibração em eficiência do detector para a geometria do filtro cuno, onde foram estudadas as influências da camada morta e do efeito de soma em cascata no detector HPGe. As correções dos valores de camada morta foram realizadas variando-se a espessura e o raio do cristal de germânio. O detector possui 75,83 cm3 de volume ativo de detecção, segundo informações fornecidas pelo fabricante. Entretanto os resultados encontrados mostraram que o valor de volume ativo real é menor do que o especificado, onde a camada morta representa 16% do volume total do cristal. A análise do filtro cuno por meio da espectrometria gama, permitiu a identificação de picos de energia. Por meio desses picos foram identificados três radionuclídeos no filtro: 108mAg, 110mAg e 60Co. A partir da calibração em eficiência obtida pelo método de Monte Carlo, o valor de atividade estimado para esses radionuclídeos está na ordem de MBq. / The Cuno filter is part of the water processing circuit of the IEA-R1 reactor and, when saturated, it is replaced and becomes a radioactive waste, which must be managed. In this work, the primary characterization of the Cuno filter of the IEA-R1 nuclear reactor at IPEN was carried out using gamma spectrometry associated with the Monte Carlo method. The gamma spectrometry was performed using a hyperpure germanium detector (HPGe). The germanium crystal represents the detection active volume of the HPGe detector, which has a region called dead layer or inactive layer. It has been reported in the literature a difference between the theoretical and experimental values when obtaining the efficiency curve of these detectors. In this study we used the MCNP-4C code to obtain the detector calibration efficiency for the geometry of the Cuno filter, and the influence of the dead layer and the effect of sum in cascade at the HPGe detector were studied. The correction of the dead layer values were made by varying the thickness and the radius of the germanium crystal. The detector has 75.83 cm3 of active volume of detection, according to information provided by the manufacturer. Nevertheless, the results showed that the actual value of active volume is less than the one specified, where the dead layer represents 16% of the total volume of the crystal. A Cuno filter analysis by gamma spectrometry has enabled identifying energy peaks. Using these peaks, three radionuclides were identified in the filter: 108mAg, 110mAg and 60Co. From the calibration efficiency obtained by the Monte Carlo method, the value of activity estimated for these radionuclides is in the order of MBq.

<p>Gradient structured (GS) metallic materials have shown unique properties including the synergy of high strength and good ductility, improved fatigue and wear/friction resistance etc. One of the severe surface modification technique, surface mechanical grinding treatment (SMGT), has been proven an effective method for the generation of gradient structures in metallic materials. Most of Ni-based superalloys are precipitation strengthened and with an extraordinary combination of high strength, ductility and resistance to oxidation at high temperatures. The precipitation behaviors of these materials are sensitive to their initial microstructures. This thesis focuses on the microstructure evolution and mechanical behaviors of two types of gradient Ni alloys. </p> <p>GS Hastelloy C-22HS and Inconel 718 (IN718) Ni-based superalloys were fabricated through the SMGT technique. The gradient structures consist of nanograined (NG) or nanolaminate (NL) surface layer and the subsurface layers with deformation twins. <i>In situ </i>compression test results reveal that intergranular back stress may contributes to the high work hardening capability of the GS C-22HS alloy. Mo-rich thick grain boundaries (GBs) formed in the gradient C-22HS samples after heat treatment. <i>In situ</i> micropillar compression studies coupled with molecular dynamics (MD) simulations reveal that the Mo-rich thick GBs are stronger barriers than conventional thin GBs to the transmission of dislocations, leading to significant strengthening. Furthermore, the formation of thick GBs also contributes to the improvement of thermal stability of nanograins in the C-22HS alloys. The gradient microstructures in the IN718 alloy changed the precipitation behavior and thermal stability of nanograins in the alloy. The studies on precipitation behaviors of GS IN718 alloy reveal that η phase formed in the severely deformed surface NG layer after annealing at 700 ^oC. Thermal stability studies show that NG IN718 alloy with grain sizes smaller than the critical value of ~ 40 nm is thermally more stable than their coarse-grained counterpart. The underlying mechanisms of strengthening and improved thermal stability of the gradient Ni-based superalloys are discussed based on transmission electron microscopy studies and MD simulations. This work suggests that tailoring the gradient microstructures may lead to the discovery of metallic materials with novel mechanical and thermodynamic properties. </p>

Catalysis is one of the Green Chemistry Principles given its importance for limiting environmental impacts and improving current processes, as well as for developing new sustainable processes and products. In order to provide more performant catalysts, this study provides a novel preparation method for controlling the distribution of metal nanoparticles (NPs) within hierarchically meso- and macroporous catalysts. It consists of the combination of latex synthesis, sonochemistry and sol-gel process. All these steps can be carried out in water, reducing environmental impact. The first step is the synthesis of latex, typically polystyrene. The second step is the sonochemical synthesis and deposition of noble metal NPs on the surface of the latex polymer. The third step is the synthesis of the support by sol-gel process using tetraethyl orthosilicate (TEOS) under controlled conditions to modulate the porosity of the final silica matrix. As a result, an original catalyst morphology is obtained with active sites preferentially located within the macropores, which are surrounded by a mesoporous matrix. Using this approach, a monodisperse polystyrene latex (~130 nm) was prepared by emulsion polymerisation and then decorated with Pt NPs (~2.3 nm) by sonochemical reduction. The mesoporous silica support was prepared by sol-gel synthesis in the presence of the decorated latex. After calcination, the organic template left behind macropores with the Pt NPs within the generated macropores. Mesopores (2-15 nm) connecting these macropores (110-400 nm) were tuned by varying the synthesis conditions. Typically, specific surface areas of 615 m2/g and total pore volumes of 0.74 cm3/g were obtained. In a first case of study, hierarchically porous Pt/SiO2 catalysts were evaluated in the selective hydrogenation of p-chloronitrobenzene (p-CNB) to produce p-chloroaniline. They exhibited activities up to 91.7 ± 2.9 molCNB/(min molPt) and selectivity values up to 100 ± 2% at 80% of conversion, in comparison with 47.7 ± 2.9 molCNB/(min molPt) and 91 ± 2%, respectively, obtained with a commercial catalyst under the same conditions. Moreover, in a second case of study, it was possible to prepare silica-supported Pd, Pd-Pt and Pd-CeO2 catalysts with hierarchical porosity (meso and macro). These materials were tested in the direct synthesis of hydrogen peroxide from hydrogen and oxygen. The best productivity of H2O2 was obtained with the bimetallic Pd-Pt catalyst with 32500 molH2O2/(h molmetal) in batch, and the best selectivity was obtained with Pd-CeO2/SiO2 catalyst (63 ± 2%) in semi-batch. In summary, this thesis proposes a new aqueous preparation method for hierarchically porous functional materials by the combination of latex synthesis, sonochemical reduction and sol-gel process. It has been demonstrated that this preparation technique provides a very powerful and versatile toolbox for catalyst tailoring and optimisation. Further perspectives to achieve improved morphologies and controlled active sites distribution are also proposed. / La catalyse est l'un des piliers pour le développement de procédés durables, car elle permet d'utiliser moins de ressources en accélérant les réactions chimiques. Afin de fournir des catalyseurs plus performants, cette étude propose une nouvelle méthode de préparation de catalyseurs pour contrôler la distribution de nanoparticules (NPs) métalliques au sein des catalyseurs hiérarchiquement poreux (méso et macro) en combinant la synthèse de latex, la réduction sonochimique et le procédé sol-gel. La première étape est la synthèse d'une empreinte porogène de billes de polystyrène (latex) obtenues par polymérisation en émulsion aqueuse. La deuxième étape est la synthèse et le dépôt de NPs de métaux nobles sur la surface des billes de polymère par voie sonochimique dans l’eau. La troisième étape est la synthèse du support catalytique par un procédé sol-gel en milieu aqueux en utilisant le latex décoré et l’orthosilicate de tétraéthyle (TEOS) dans des conditions contrôlées pour moduler la porosité finale de la matrice de silice (mésoporeuse). Toutes les étapes de cette approche sont effectuées dans l'eau, ce qui limite les impacts environnementaux de la préparation du catalyseur. L'élimination du porogène (latex) par calcination génère les macropores. Le matériau résultant possède alors une morphologie inédite pour un catalyseur, avec des macropores fonctionnalisés par des NPs métalliques, dans une matrice de silice mésoporeuse. Ainsi, il a été possible de synthétiser un latex monodisperse de polystyrène (~130 nm), lequel a été décoré avec des NPs de Pt (~2.3 nm) par réduction sonochimique. Le matériau final de silice a présenté des mésopores (2-15 nm) reliant les macropores (110-400 nm) contenant les NPs de Pt. Il a été possible d'obtenir des surfaces spécifiques et des volumes poreux totaux de 615 m2/g et 0,74 cm3/g, respectivement. Dans un premier cas d'étude, des catalyseurs de Pt/SiO2 à porosité hiérarchique ont été évalués dans l'hydrogénation sélective du p-chloronitrobenzene (p-CNB) pour produire la p-chloroaniline. Ils ont présenté des activités catalytiques allant jusqu'à 91,7 ± 2,9 molCNB/(min molPt) et des sélectivités jusqu'à 100 ± 2% à 80% de conversion, par rapport à 47,7 ± 2,9 molCNB/(min molPt) et 91 ± 2%, respectivement, obtenus dans les mêmes conditions avec un catalyseur commercial. Dans un deuxième cas d'étude, des catalyseurs à base de Pd, Pd-Pt et Pd-CeO2 supportés sur de la silice à porosité hiérarchique ont été préparés et testés dans la synthèse directe du peroxyde d'hydrogène. La meilleure productivité a été obtenue avec le catalyseur bimétallique Pd-Pt avec 32500 molH2O2/(h molmétal) en batch, et la meilleure sélectivité a été obtenue avec le catalyseur Pd-CeO2/SiO2 (63 ± 2%) en semi-continu. En résumé, cette thèse propose une nouvelle méthode de préparation dans l’eau de matériaux fonctionnels à porosité hiérarchique en combinant la synthèse de latex, la réduction sonochimique et le procédé sol-gel. Il a été démontré que cette technique de préparation fournit une boîte à outils très puissante et polyvalente pour la préparation et l'optimisation des catalyseurs. Des perspectives pour améliorer davantage les morphologies et la distribution contrôlée des sites actifs sont également proposées.

Malaria is one of the most serious tropical infectious diseases affecting mankind. The prevention of the disease is hampered by the increasing resistance of the parasite to existing chemotherapy and -prophylaxis drugs. The need for novel therapeutic targets and drugs is therefore enormous and the understanding of the biochemistry of the parasite is imperative. The aim of this study was the identification and molecular characterisation of the eDNA of one such metabolic target protein, ornithine decarboxylase (ODC), in the human malaria parasite P. falciparum. The P. falciparum ODC eDNA was isolated by means of a modified RT-PCR technique, RACE. No sequence data were available and the primers used were based on consensus areas identified in the protein sequences from other related organisms. The isolation and identification of the eDNA with degenerate primers was successful in 3' -RACE, but necessitated the optimisation of the eDNA synthesis protocol and the use of total RNA as starting material. The sequence obtained facilitated the application of 5' -RACE with ODC-specific primers based on the 3' -RACE sequence data. The full-length ODC eDNA sequence was obtained by overlap-alignment of various segments. A novel suppression PCR technology was applied during the 5' -RACE in order to create an uncloned eDNA library of amplified cDNAs representing only the mRNA population. The P. falciparum ODC eDNA contains an open reading frame of ---2847 bp and translates to a large 939 amino acid protein. The protein contained large internal insertions and was extended by '""273 N-terminal residues compared to ODCs from other organisms. Several possible signature motifs were identified for phosphorylation, glycosylation and transamidation. The P. falciparum ODC protein seems to contain more hydrophilic and a-helix forming residues. These characteristics should be further investigated after expression of the recombinant protein. The isolation of the P. falciparum ODC eDNA facilitates the validation of this protein as an antimalarial target. / Dissertation (MSc)--University of Pretoria, 1998. / gm2014 / Biochemistry / unrestricted

In the first part of this thesis, a Chomsky-Schützenberger characterisation and an automaton characterisation of multiple context-free grammars are proved. Furthermore, a framework for approximation of automata with storage is described. The second part develops each of the three theoretical results into a parsing algorithm.

<div>Polymer bonded explosives (PBXs) consist of energetic material (EM) crystals embedded inside a polymeric binder. These are highly heterogeneous structures designed to explode under controlled conditions. However, accidental ignition of PBXs leading to deflagration, or even detonation, may take place due to non-shock stimulus such as low velocity impacts and vibration. Thus, assessing the safety of PBXs under non-shock stimulus is very important.</div><div><br></div><div>The ignition in PBXs depends on several microstructural features which include mechanical properties of EM particles and polymeric binder, as well as the adhesive properties of interface between EM particles and binder. It is also sensitive to initial defects in EM particles including cracks or voids. EM particle size distribution, distance between particles and their relative location are also shown to be affecting the ignition behavior of PBXs. This study focuses on PBX composition consisting of HMX as EM and Sylgard or HTPB as polymeric binder. Among several mechanisms of hot-spot formation, this study focuses on frictional heating at cracks or debonded surfaces.</div><div><br></div><div>Finite element simulations are performed on a domain containing a single EM particle embedded inside polymer binder under compressive and tensile loading at 10 m/s. The effect of the binder properties and the particle surface properties, on damage evolution and corresponding temperature rise due to frictional heat generation, is investigated. Two binders, Sylgard and HTPB, while two surface qualities for HMX particle, low and high, are compared. The adhesion strength of the particle-polymer interface is varied and damage evolution is qualitatively compared with experimental results to estimate interfacial energy release rate for HMX-Sylgard and HMX-HTPB interfaces. Simulations of two HMX particles inside Sylgard binder, subjected to vibration loading, are performed to analyze the effect of particle-particle distance and relative location of particles on the damage evolution and frictional heating in the particles.</div><div><br></div><div>The results of impact simulations show that the low surface quality HMX particle inside HTPB is likely to propagate cracks as compared to high surface quality particle. The HMX particle inside Sylgard shows crack propagation irrespective of particle surface quality. The impact simulations with the lower stiffness binder do not show a significant increase in temperature after impact. A polymer with higher stiffness induces more particle damage under impact contributing to a larger temperature rise. Furthermore, high quality surface and higher adhesion strength induces larger stresses and increase the temperature rise. The vibration simulations show that a small particle is less likely to damage when it is shielded by a large particle irrespective of its distance, within 40-200$\mu$m, from the large particle. However, the small particle is likely to damage when it is in parallel to the large particle with respect to loading. The temperature rise in the small particle is higher than the larger particle only in case of parallel configuration. The adhesion between the particles and the polymer has a direct effect on the formation of hot-spots due to friction and through local increase of compressive stresses that may cause a surge in heat generation.</div><div><br></div><div>The energetic materials often show anisotropy in elastic and crystalline properties. Fracture in HMX along the preferred cleavage plane is considered. Anisotropy in the elastic constants is also incorporated in the fracture model. The dependence of pressure on temperature is considered using Mie-Gruneisen equation of state which is shown to be important for damage evolution in HMX at impact velocity of 100 m/s.</div>