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.

Low-temperature phase transition in glycine–glutaric acid co-crystals studied by single-crystal X-ray diffraction, Raman spectroscopy and differential scanning calorimetry

2012 ◽  
Vol 68 (3) ◽  
pp. 287-296 ◽  
Author(s):  
Boris A. Zakharov ◽  
Evgeniy A. Losev ◽  
Boris A. Kolesov ◽  
Valeri A. Drebushchak ◽  
Elena V. Boldyreva
Keyword(s):  
Phase Transition ◽  
Differential Scanning Calorimetry ◽  
Raman Spectroscopy ◽  
Single Crystal ◽  
Glutaric Acid ◽  
Group Symmetry ◽  
Temperature Phase ◽  
X Ray Diffraction ◽  
Scanning Calorimetry ◽  
X Ray

The occurrence of a first-order reversible phase transition in glycine–glutaric acid co-crystals at 220–230 K has been confirmed by three different techniques – single-crystal X-ray diffraction, polarized Raman spectroscopy and differential scanning calorimetry. The most interesting feature of this phase transition is that every second glutaric acid molecule changes its conformation, and this fact results in the space-group symmetry change from P21/c to P\bar 1. The topology of the hydrogen-bonded motifs remains almost the same and hydrogen bonds do not switch to other atoms, although the hydrogen bond lengths do change and some of the bonds become inequivalent.

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.

Characterization of New Cocrystals by Raman Spectroscopy, Powder X-ray Diffraction, Differential Scanning Calorimetry, and Transmission Raman Spectroscopy

2010 ◽  
Vol 10 (5) ◽  
pp. 2360-2371 ◽  
Author(s):  
M. A. Elbagerma ◽  
H. G. M. Edwards ◽  
T. Munshi ◽  
M. D. Hargreaves ◽  
Pavel Matousek ◽  
...  
Keyword(s):  
Differential Scanning Calorimetry ◽  
Raman Spectroscopy ◽  
X Ray Diffraction ◽  
Scanning Calorimetry ◽  
X Ray ◽  
Transmission Raman

scholarly journals Improvement of the optical and photocatalytic properties of ZnAl2O4: 1% La3+, x% Pb2+ nanoparticles synthesized by citrate sol-gel route

2021 ◽  
Author(s):  
Hichem Filali ◽  
Nahman Boukheit ◽  
Rafika Bouhroum ◽  
Wassila Chekirou ◽  
Ahcène Karaali
Keyword(s):  
Raman Spectroscopy ◽  
Single Phase ◽  
Sol Gel ◽  
X Ray Diffraction ◽  
Scanning Calorimetry ◽  
Constant Amount ◽  
Pure Zinc ◽  
Characterization Methods ◽  
X Ray ◽  
Gel Technique

Abstract Samples of pure zinc aluminate (ZnAl2O4) and doped both with lead (Pb2+) at different ratios (0, 0.5, 1, 1.5, 2 and 2.5% mol) and a constant amount of lanthanum (La: 1% mol), were prepared by the citrate sol-gel technique, and then annealed at 900°C for 2h. In order to study the structural, optical and thermal properties; different characterization methods were used, such as: powder X-ray diffraction (XRD), scanning electron microscope (SEM), energy dispersive X-ray spectroscopy (EDX), differential scanning calorimetry (DSC), TGA, Fourier transform infrared spectroscopy (FTIR) and Raman spectroscopy. The Analyzes by XRD revealed the presence of the cubic single phase ZnAl2O4 for all samples, with a crystallites size between 19 and 25 nm. These results were confirmed using FTIR, Raman spectroscopy and SEM. Also, photocatalytic study for different samples of ZnAl2O4 shows that they can be used like as photocatalyst and good adsorbents for degradation of Hexamethyl crystallized violet dye in aqueous solution.

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.

Thermodynamic and Structural Properties of Mev Ion Beam Amorphized Silicon

1989 ◽  
Vol 157 ◽  
Author(s):  
S. Roorda ◽  
W.C. Sinke ◽  
J.M. Poate ◽  
D.C. Jacobson ◽  
P. Fuoss ◽  
...  
Keyword(s):  
Differential Scanning Calorimetry ◽  
Raman Spectroscopy ◽  
Structural Properties ◽  
Atomic Structure ◽  
Structural Relaxation ◽  
Ion Beam ◽  
X Ray Diffraction ◽  
Scanning Calorimetry ◽  
X Ray ◽  
Amorphous Si

ABSTRACTThermodynamic and structural properties of amorphous Si (a-Si), prepared by MeV 28Si+-ion implantation are investigated by differential scanning calorimetry, Raman spectroscopy and X-ray diffraction. The influence of thermal annealing below 500 °C on a-Si is investigated with these different probes. The observed changes result from structural relaxation. Raman spectroscopy and X-ray diffraction show that structural relaxation is accompanied by changes in the average atomic structure.

scholarly journals Recent Advances in Solid-State Analysis of Pharmaceuticals

2015 ◽  
Vol 2 (1) ◽  
pp. 13-20 ◽  
Author(s):  
Syed Nasir Abbas Bukhari ◽  
Ng Shin Hwei ◽  
Ibrahim Jantan
Keyword(s):  
Electron Microscopy ◽  
Nuclear Magnetic Resonance ◽  
Differential Scanning Calorimetry ◽  
Raman Spectroscopy ◽  
Solid State ◽  
Magnetic Resonance ◽  
Spatial Resolution ◽  
X Ray Diffraction ◽  
Scanning Calorimetry ◽  
X Ray

Current analytical techniques for characterizing solid-state pharmaceuticals include powder x-ray diffraction, differential scanning calorimetry, thermogravimetric analysis, infrared spectroscopy, Raman spectroscopy, electron microscopy and nuclear magnetic resonance. Powder x-ray diffraction and differential scanning calorimetry are mainstream techniques but they lack spatial resolution. Scanning electron microscopy and micro-Raman spectroscopy provide good chemical and optical characterization but they are not capable of analysing very small nanoparticles. Transmission electron microscopy and nano-thermal analysis can provide explicit characterization of nanoparticles but they are invasive. Nuclear magnetic resonance offers good spatial resolution but its use is mainly limited by poor sensitivity and high costs. In view of the many challenges posed by existing methods, new and novel techniques are being continually researched and developed to cater to the growing number of solid formulations in the pipeline and in the market. Some of the recent advances attained in the solid-state analysis of pharmaceutical are summarized in this review article.

scholarly journals Structural Characterization of Co-Crystals of Chlordiazepoxide with p-Aminobenzoic Acid and Lorazepam with Nicotinamide by DSC, X-ray Diffraction, FTIR and Raman Spectroscopy

Pharmaceutics ◽  
2020 ◽  
Vol 12 (7) ◽  
pp. 648
Author(s):  
Patrycja Garbacz ◽  
Dominik Paukszta ◽  
Artur Sikorski ◽  
Marek Wesolowski
Keyword(s):  
Raman Spectroscopy ◽  
Water Solubility ◽  
Proton Exchange ◽  
Aminobenzoic Acid ◽  
X Ray Diffraction ◽  
Scanning Calorimetry ◽  
X Ray ◽  
Pharmaceutical Ingredients ◽  
Crystallization Procedure ◽  
Ftir And Raman Spectroscopy

The low water solubility of benzodiazepines seriously affects their bioavailability and, in consequence, their biological activity. Since co-crystallization has been found to be a promising way to modify undesirable properties in active pharmaceutical ingredients, the objective of this study was to prepare co-crystals of two benzodiazepines, chlordiazepoxide and lorazepam. Using different co-crystallization procedures, slurry evaporation and liquid-assisted grinding, co-crystals of chlordiazepoxide with p-aminobenzoic acid and lorazepam with nicotinamide were prepared for the first time. Confirmation that co-crystals were obtained was achieved through a comparison of the data acquired for both co-crystals using differential scanning calorimetry (DSC), powder X-ray diffraction (PXRD), Fourier-transform infrared (FTIR) and Raman spectroscopy, with comparisons acquired for the physical mixtures of both benzodiazepines and coformers. The compatibility of PXRD patterns of both benzodiazepines co-crystals with those contained in the base Powder Diffraction File (PDF-4+) suggests that new crystal structures were indeed created under the co-crystallization procedure. Single-crystal X-ray diffraction revealed that a chlordiazepoxide co-crystal with p-aminobenzoic acid and a lorazepam co-crystal with nicotinamide crystallized in the monoclinic P21/n and P21/c space group, respectively, with one molecule of benzodiazepine and one of coformer in the asymmetric unit. FTIR and Raman spectroscopy corroborated that benzodiazepine and coformer are linked by a hydrogen bond without proton exchange. Furthermore, a DSC study revealed that single endothermic DSC peaks assigned to the melting of co-crystals differ slightly depending on the co-crystallization procedures and solvent used, as well as differing from those of starting components.

scholarly journals Exceptionally High Temperature Spin Crossover in Amide-Functionalised 2,6-bis(pyrazol-1-yl)pyridine Iron(II) Complex Revealed by Variable Temperature Raman Spectroscopy and Single Crystal X-ray Diffraction.

2021 ◽  
Author(s):  
Max Attwood ◽  
Hiroki Akutsu ◽  
Lee Martin ◽  
Toby J Blundell ◽  
Pierre LeMagueres ◽  
...  
Keyword(s):  
Differential Scanning Calorimetry ◽  
Raman Spectroscopy ◽  
High Temperature ◽  
Spin Crossover ◽  
Variable Temperature ◽  
Squid Magnetometry ◽  
X Ray Diffraction ◽  
Scanning Calorimetry ◽  
X Ray ◽  
Complex Salts

The synthesis of a novel amide-functionalised 2,6-bis(pyrazol-1-yl)pyridine-4-carboxamide ligand (bppCONH2) is described. The complex salts [Fe(bppCONH2)2](BF4)2 and [Fe(bppCONH2)2](ClO4)2 were synthesised and characterised by SQUID magnetometry, differential scanning calorimetry, variable temperature Raman...

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