scholarly journals Mixing and Quantifying Multi-Component Materials for Pyrotechnic Applications

2014 ◽  
Vol 70 (a1) ◽  
pp. C1233-C1233
Author(s):  
Lisa Blair ◽  
Simon Coles ◽  
Ian Sinclair ◽  
Ranko Vrcelj
Keyword(s):  
Energetic Materials ◽  
Crystalline Lattice ◽  
X Ray Diffraction ◽  
Scanning Calorimetry ◽  
X Ray ◽  
Macroscopic Structure ◽  
Metal Organic ◽  
Physical Mixing ◽  
Mixing Method ◽  
Distribution Of Components

This multidisciplinary research is looking at the relationship between components of a pyrotechnic product and how manufacturing, in particular the mixing method employed, affects its macroscopic structure and properties. For pyrotechnics to produce the desired effect the ingredients must be intimately mixed, however, the present physical mixing approach can lead to inconsistencies in performance between batches. X-ray computed tomography (CT) was used to investigate the distribution of components in a pyrotechnic mixture. Near-neighbour distances between particles were calculated and used to assess the homogeneity of the mixtures and the efficiency of combustion. Another strand of this research to overcome batch inconsistencies was by chemically binding pyrotechnic ingredients rather than physically mixing them together. One method of achieving this was through incorporating two or more components within the same crystalline lattice. This may be achieved through co-crystallisation or coordination in functional frameworks, thereby reducing the number of components in a physical mixture and minimising the variation between batches. Pang et al. have investigated using MOFs (metal-organic frameworks) to stabilise energetic materials [1]. The research presented here uses MOFs to bring together fuels and oxidisers into one framework to create a MOFirework. Numerous linkers and metal centres were investigated to build up a structural family to correlate structure with pyrotechnic function (e.g. changing burn colour; Sr = red, Ba = green). Both powder and single crystal X-ray diffraction were used to characterise the products. Differential scanning calorimetry was used to look at the thermal profiles to investigate their possible uses as pyrotechnics. Lastly, a burn test was carried out to determine their pyrotechnic effect (e.g. gas, smoke, gas, light, heat, colour, and sound) and quantitatively link this to structure.

Structure and properties of Al–Mg mechanical alloys

2003 ◽  
Vol 18 (8) ◽  
pp. 1827-1836 ◽  
Author(s):  
Mirko Schoenitz ◽  
Edward L. Dreizin
Keyword(s):  
Solid Solution ◽  
Energetic Materials ◽  
Amorphous Material ◽  
Bulk Composition ◽  
X Ray Diffraction ◽  
Scanning Calorimetry ◽  
X Ray ◽  
Β Phase ◽  
Α Phase ◽  
Diffraction Microscopy

Mechanically alloys in the Al–Mg binary system in the range of 5–50 at.% Mg were produced for prospective use as metallic additives for propellants and explosives. Structure and composition of the alloys were characterized by x-ray diffraction microscopy (XRD) and scanning electron microscopy. The mechanical alloys consisted of a supersaturated solid solution of Mg in the α aluminum phase, γ phase (Al12Mg17), and additional amorphous material. The strongest supersaturation of Mg in the α phase (20.8%) was observed for bulk Mg concentrations up to 40%. At 30% Mg, the γ phase formed in quantities detectable by XRD; it became the dominating phase for higher Mg concentrations. No β phase (Al3Mg2) was detected in the mechanical alloys. The observed Al solid solution generally had a lower Mg concentration than the bulk composition. Thermal stability and structural transitions were investigated by differential scanning calorimetry. Several exothermic transitions, attributed to the crystallization of β and γ phases were observed. The present work provides the experimental basis for the development of detailed combustion and ignition models for these novel energetic materials.

scholarly journals Single-Step Synthesis and Interface Tuning of Core–shell Metal–organic Framework Nanoparticles

2020 ◽  
Author(s):  
Kieran Orr ◽  
Sean M. Collins ◽  
Emily Reynolds ◽  
Frank Nightingale ◽  
Hanna Boström ◽  
...  
Keyword(s):  
Spatial Distribution ◽  
Metal Organic Framework ◽  
Single Step ◽  
Core Shell ◽  
Composition Gradient ◽  
X Ray Diffraction ◽  
X Ray ◽  
Metal Organic ◽  
Distribution Of Components ◽  
Organic Framework

Control over the spatial distribution of components in metal–organic frameworks has potential to unlock improved performance and new behaviour in separations, sensing and catalysis. We report an unprecedented single-step synthesis of multi-component metal–organic framework (MOF) nanoparticles, which form with a core–shell structure whose internal interface can be systematically tuned. We use scanning transmission electron microscopy, X-ray energy dispersive spectroscopy and a new composition gradient model to fit high-resolution X-ray diffraction data to show how core–shell composition and interface characteristics are intricately controlled by synthesis temperature and reaction composition. Particle formation is investigated by in situ X-ray diffraction, which reveals that the spatial distribution of components evolves with time and is determined by the interplay of phase stability, crystallisation kinetics and diffusion. This work opens up new possibilities for the control and characterisation of functionality, component distribution and interfaces in MOF-based materials.

Exothermic behaviour of aluminium and graphene as a fuel in Fe2O3 based nanothermite

2021 ◽  
Vol 0 (0) ◽  
Author(s):  
Priya Thakur ◽  
Vimal Sharma ◽  
Nagesh Thakur
Keyword(s):  
Raman Spectroscopy ◽  
Energy Release ◽  
Graphene Sheets ◽  
X Ray Diffraction ◽  
Scanning Calorimetry ◽  
X Ray ◽  
Layer Graphene ◽  
Physical Mixing ◽  
Field Emission Electron Microscopy ◽  
Fesem Micrographs

Abstract The main frontier of this research is to study the influence of multi-layer graphene (MLG) and aluminium as a fuel in Al/Fe2O3 and MLG/Fe2O3 nanothermites, fabricated by physical mixing and ultrasonication techniques. To study the structural and energy release properties, prepared samples were characterized by XRD, FESEM, EDS, FTIR, Raman spectroscopy and DSC. The X-ray diffraction (XRD) technique showed that all the phases remain intact during the synthesis. Field emission electron microscopy (FESEM) micrographs displayed the surface morphology of the samples, and besides this, energy dispersive spectroscopy (EDS) was used to check the elemental composition of samples. Raman spectroscopy revealed that the ultrasonication waves did not deteriorate the aromatic structure of graphene sheets. Fourier transform infrared spectroscopy (FTIR) spectra were used to observe the information about various functional groups present in the thermite samples. The exothermic energy released by the thermite reaction in both the samples was investigated by differential scanning calorimetry (DSC) and the observed values of energy release for Al/Fe2O3 and MLG/Fe2O3 are 215 J/g and 1640 J/g.

scholarly journals ENHANCEMENT OF LORNOXICAM SOLUBILITY BY INCLUSION COMPLEXATION WITH CYCLODEXTRIN: PREPARATION AND CHARACTERIZATION

2016 ◽  
Vol 9 (1) ◽  
pp. 132 ◽  
Author(s):  
Shahira Fawzy El-menshawe ◽  
Essam Eissa ◽  
Adel A. Ali ◽  
Ahmed A. Abderhman
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Freeze Drying ◽  
Inclusion Complexation ◽  
X Ray Diffraction ◽  
Scanning Calorimetry ◽  
X Ray ◽  
Physical Mixing ◽  
Solid Complexes ◽  
Scanning Electron

<p><strong>Objective: </strong>Lornoxicam is a potent anti-inflammatory drug which has analgesic and antipyretic properties. It is water-insoluble powder. The inclusion complexes of lornoxicam (LOR) with β-cyclodextrin (βCD) and 2-hydroxypropyl-β-cyclodextrin (HPCD) were prepared and characterised in order to improve the solubility of the drug and enhance its bioavailability.</p><p><strong>Methods: </strong>Complexes were prepared by physical mixing and freeze-drying in three different drug/polymer ratios (1:1, 1:2 and 3:2). The solid complexes were characterised through differential scanning calorimetry (DSC), scanning electron microscopy (SEM), X-ray diffraction, nuclear magnetic resonance (NMR) spectroscopy, and Fourier transformed infrared (FTIR) spectroscopy.</p><p><strong>Results: </strong>The data showed that LOR may be complexed with cyclodextrin (CD) forming soluble complexes. The lyophilized 1:2 LOR/HPCD complex is the most soluble.</p><p><strong>Conclusion: </strong>Solubility increases with lyophilization than with physical mixing and by the use of HPCD than βCD in complexation.</p>

scholarly journals Inclusion of the Phytoalexin trans-Resveratrol in Native Cyclodextrins: A Thermal, Spectroscopic, and X-Ray Structural Study

Molecules ◽  
2020 ◽  
Vol 25 (4) ◽  
pp. 998 ◽  
Author(s):  
Laura Catenacci ◽  
Milena Sorrenti ◽  
Maria Cristina Bonferoni ◽  
Lee Hunt ◽  
Mino R. Caira
Keyword(s):  
Inclusion Complexation ◽  
Exothermic Effect ◽  
X Ray Diffraction ◽  
Scanning Calorimetry ◽  
X Ray ◽  
Physical Mixing ◽  
Ft Ir ◽  
Co Precipitation ◽  
Ft Ir Spectroscopy ◽  
Severe Disorder

The aim of the study was to determine the feasibility of complexation between the antioxidant trans-resveratrol (RSV) and underivatized cyclodextrins (CDs) using a variety of preparative methods, including physical mixing, kneading, microwave irradiation, co-evaporation, and co-precipitation techniques. Products were characterized using differential scanning calorimetry (DSC), simultaneous thermogravimetric/DSC analysis (TGA/DSC), Fourier transform infrared (FT-IR) spectroscopy, and powder X-ray diffraction (PXRD). With α-CD and RSV, sample amorphization was revealed by PXRD and FT-IR, but no definitive inclusion complexation was evident. Similar results were obtained in attempts to complex RSV with β-CD. However, complex formation between γ-CD and RSV was evident from observation of an endo-/exothermic effect appearing in the DSC trace of the product from kneading and was further corroborated by FT-IR and PXRD methods. The latter technique indicated complexation unequivocally as the diffraction peak profile for the product matched that for known isostructural γ-CD complexes. Single crystal X-ray analysis followed, confirming the predicted complex between γ-CD and RSV. A combination of 1H NMR and TGA data yielded the complex formula (γ-CD)3·(RSV)4·(H2O)62. However, severe disorder of the RSV molecules prevented their modeling. In contrast, our previous studies of the inclusion of RSV in methylated CDs yielded crystals with only minor guest disorder.

A Micro Fuse Realized by Integrating Al/CuO-Based Nanoenergetic Materials on a Micro Wire

2011 ◽  
Vol 694 ◽  
pp. 249-255 ◽  
Author(s):  
Xue Song ◽  
Guang Cheng Yang ◽  
Fu De Nie
Keyword(s):  
Electron Microscopy ◽  
Energetic Materials ◽  
X Ray Diffraction ◽  
Scanning Calorimetry ◽  
X Ray ◽  
Nanoenergetic Materials ◽  
Cu Film ◽  
Improved Performance ◽  
High Level ◽  
Scanning Electron

Nano energetic materials (nEMs) have improved performance in energy release, ignition, and mechanical properties compared to their bulk or micro counterparts. In this study a micro fuse developed by intergrating Al/CuO-based nanoenergetic materials on a micro wire. CuO nanowires are synthesized by thermally annealing Cu film deposited onto a micro wire. Nano-Al is integrated with the nanowires by thermal to realize an Al/CuO based nEMs. It allows batch and high level of integration and reliability. The micro fuse is tested by open-air combustion testing and characterized by scanning electron microscopy, x-ray diffraction, differential thermal analysis and differential scanning calorimetry.

scholarly journals Synthesis of Energetic 7-Nitro-3,5-dihydro-4H-pyrazolo[4,3-d][1,2,3]triazin-4-one Based on a Novel Hofmann-Type Rearrangement

Molecules ◽  
2021 ◽  
Vol 26 (23) ◽  
pp. 7319
Author(s):  
Fu-Qiang Bi ◽  
Yi-Fen Luo ◽  
Jun-Lin Zhang ◽  
Huan Huo ◽  
Bo-Zhou Wang
Keyword(s):  
Differential Scanning Calorimetry ◽  
Ir Spectroscopy ◽  
Organic Synthesis ◽  
Energetic Materials ◽  
Detonation Properties ◽  
X Ray Diffraction ◽  
Scanning Calorimetry ◽  
X Ray ◽  
Calculation Results ◽  
First Time

Rearrangement reactions are efficient strategies in organic synthesis and contribute enormously to the development of energetic materials. Here, we report on the preparation of a fused energetic structure of 7-nitro-3,5-dihydro-4H-pyrazolo[4,3-d][1,2,3]triazin-4-one (NPTO) based on a novel Hofmann-type rearrangement. The 1,2,3-triazine unit was introduced into the fused bicyclic skeleton from a pyrazole unit for the first time. The new compound of NPTO was fully characterized using multinuclear NMR and IR spectroscopy, elemental analysis as well as X-ray diffraction studies. The thermal behaviors and detonation properties of NPTO were investigated through a differential scanning calorimetry (DSC-TG) approach and EXPLO5 program-based calculations, respectively. The calculation results showed similar detonation performances between NPTO and the energetic materials of DNPP and ANPP, indicating that NPTO has a good application perspective in insensitive explosives and propellants.

scholarly journals Single-Step Synthesis and Interface Tuning of Core–shell Metal–organic Framework Nanoparticles

2020 ◽  
Author(s):  
Kieran Orr ◽  
Sean M. Collins ◽  
Emily Reynolds ◽  
Frank Nightingale ◽  
Hanna Boström ◽  
...  
Keyword(s):  
Spatial Distribution ◽  
Metal Organic Framework ◽  
Single Step ◽  
Core Shell ◽  
Composition Gradient ◽  
X Ray Diffraction ◽  
X Ray ◽  
Metal Organic ◽  
Distribution Of Components ◽  
Organic Framework

Control over the spatial distribution of components in metal–organic frameworks has potential to unlock improved performance and new behaviour in separations, sensing and catalysis. We report an unprecedented single-step synthesis of multi-component metal–organic framework (MOF) nanoparticles, which form with a core–shell structure whose internal interface can be systematically tuned. We use scanning transmission electron microscopy, X-ray energy dispersive spectroscopy and a new composition gradient model to fit high-resolution X-ray diffraction data to show how core–shell composition and interface characteristics are intricately controlled by synthesis temperature and reaction composition. Particle formation is investigated by in situ X-ray diffraction, which reveals that the spatial distribution of components evolves with time and is determined by the interplay of phase stability, crystallisation kinetics and diffusion. This work opens up new possibilities for the control and characterisation of functionality, component distribution and interfaces in MOF-based materials.

Revisiting the High-Pressure Properties of the Metal-Organic Frameworks ZIF-8 and ZIF-67

2020 ◽  
Author(s):  
Pia Vervoorts ◽  
Stefan Burger ◽  
Karina Hemmer ◽  
Gregor Kieslich
Keyword(s):  
High Pressure ◽  
State Of The Art ◽  
Energy Landscape ◽  
Structural Flexibility ◽  
Zeolitic Imidazolate Frameworks ◽  
Stimuli Responsive ◽  
X Ray Diffraction ◽  
X Ray ◽  
Open Questions ◽  
Metal Organic

The zeolitic imidazolate frameworks ZIF-8 and ZIF-67 harbour a series of fascinating stimuli responsive properties. Looking at their responsitivity to hydrostatic pressure as stimulus, open questions exist regarding the isotropic compression with non-penetrating pressure transmitting media. By applying a state-of-the-art high-pressure powder X-ray diffraction setup, we revisit the high-pressure behaviour of ZIF-8 and ZIF-67 up to <i>p</i> = 0.4 GPa in small pressure increments. We observe a drastic, reversible change of high-pressure powder X-ray diffraction data at <i>p</i> = 0.3 GPa, discovering large volume structural flexibility in ZIF-8 and ZIF-67. Our results imply a shallow underlying energy landscape in ZIF-8 and ZIF-67, an observation that might point at rich polymorphism of ZIF-8 and ZIF-67, similar to ZIF-4(Zn).<br>

Revisiting the High-Pressure Properties of the Metal-Organic Frameworks ZIF-8 and ZIF-67

2020 ◽  
Author(s):  
Pia Vervoorts ◽  
Stefan Burger ◽  
Karina Hemmer ◽  
Gregor Kieslich
Keyword(s):  
High Pressure ◽  
State Of The Art ◽  
Energy Landscape ◽  
Structural Flexibility ◽  
Zeolitic Imidazolate Frameworks ◽  
Stimuli Responsive ◽  
X Ray Diffraction ◽  
X Ray ◽  
Open Questions ◽  
Metal Organic

The zeolitic imidazolate frameworks ZIF-8 and ZIF-67 harbour a series of fascinating stimuli responsive properties. Looking at their responsitivity to hydrostatic pressure as stimulus, open questions exist regarding the isotropic compression with non-penetrating pressure transmitting media. By applying a state-of-the-art high-pressure powder X-ray diffraction setup, we revisit the high-pressure behaviour of ZIF-8 and ZIF-67 up to <i>p</i> = 0.4 GPa in small pressure increments. We observe a drastic, reversible change of high-pressure powder X-ray diffraction data at <i>p</i> = 0.3 GPa, discovering large volume structural flexibility in ZIF-8 and ZIF-67. Our results imply a shallow underlying energy landscape in ZIF-8 and ZIF-67, an observation that might point at rich polymorphism of ZIF-8 and ZIF-67, similar to ZIF-4(Zn).<br>

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