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Statistical Optimization of a Novel Approach for the Reductive Debenzylation of 2,4,6,8,10,12-Hexabenzyl-2,4,6,8,10,12-hexaazaisowurtzitane Using Pd@SiO2 Nano Catalyst

Zarandi M., Bayat Y., Zebardasti A., Khayrabadi A. A.

Central European Journal of Energetic Materials

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2017

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Vol. 14, no. 4

984--995

EN

The synthesis of 2,6,8,12-tetraacetyl-4,10-dibenzyl-2,4,6,8,10,12-hexaazaisowurtzitane (TADB), from 2,4,6,8,10,12-hexabenzyl-2,4,6,8,10,12-hexaazaisowurtzitane(HBIW) is a key step in the preparation of 2,4,6,8,10,12-hexanitro-2,4,6,8,10,12-hexaazaisowurtzitane (HNIW or CL-20). In this study, a novel highly efficient nano catalyst based on Pd@SiO2 was used for the reductive debenzylation of HBIW. It is notable that an orthogonal array design OA9 was applied as a statistical optimization method for the synthesis of TADB. The current application of the Taguchi method in optimizing the experimental parameters of the TADB synthetic procedure was successful. TADB was synthesized by investigating the effect of the reaction conditions, such as catalyst percentage, time (h) and temperature (°C). The effects of these factors on the yield of TADB were evaluated quantitavely by the analysis of variance (ANOVA). The Pd@SiO2 nano catalyst, consisting of a palladium core with SiO2 monolayer shells, was synthesized and characterized by SEM, TEM and IR spectroscopy. The optimum condition indicated that the use of fresh Pd@SiO2 nano catalyst provides a high yield (90%). The use of Pd@SiO2 nano catalyst after recovery gave a yield of 65%.

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Study on nano scale pyrotechnic star chemicals in aerial fireworks manufacturing

Azhagurajan A., Ruvankumar M.

Journal of Achievements in Materials and Manufacturing Engineering

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2016

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Vol. 74, nr 1

5--10

EN

Purpose: Firework products are commonly used by people during festival times. Recently people are attracted by aerial display type fireworks because of its mesmeric display performance in the sky. Aerial firework composition consists of various chemicals like aluminium (Al), sulphur (S), potassium nitrate (KNO3), strontium nitrate, sodium nitrate etc., since these mixtures are hazardous at certain factors like improper mixing of chemicals and presence of moisture, these sources lead to blasting of aerial firework at ground level itself. In normal conventional aerial composition, the usage of chemical is higher and cause more liberation of pollutant in atmosphere. Meanwhile by converting the same composition into nano particles, usage of chemical in aerial fireworks is reduced because of their quick burning rate. Design/methodology/approach: Ball milling was used for converting all the chemicals into nano particles around 100 nm. Impact sensitivity of the pyrotechnic mixture was tested using the BAM method with an impact sensitivity tester. The friction sensitiveness was determined using a friction tester using the common test methods of BAM25 and corresponded to the UN recommendations on the transport of dangerous goods. DSC and SEM analysis were used as well. Findings: By reducing the particle size of aerial firework, it reduces environmental damage by reducing the sulphur dioxide, carbon dioxide, carbon monoxide, nitroxide etc., formation by complete combustion of chemicals. The sound and sparkling effect can also be achieved higher than the conventional fireworks. Practical implications: The quantity of the chemicals used to manufacture the conventional firework composition can be reduced by converting it to the nano size. This reduces the release of pollutant in atmosphere and provides safety to environment.

3

Study of the Nanotechnology in Manufacture of Generators

Sheng J. G.

Przegląd Elektrotechniczny

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2012

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R. 88, nr 3b

39-41

EN

With the development of science and technology, the smaller sizes generator, the more attention by people. The main purpose of this article is to manufacture three-phase nanogenerator and piezoelectric nanogenerator under vibration, and their working principle are introduced and their performances are studied. The results show that, using the present nanomaterials, three-phase nanogenerator and piezoelectric nanogenerator can be prepared. In ambient vibration condition, piezoelectric materials produce larger rated current and voltage. However, copper laps cutting magnetic line of force produce less rated current and voltage. So the piezoelectric nanogenerator can be separately used to supply power. It may produce higher voltage, current and power if three-phase nanogenerator and piezoelectric nanogenerator in series-parallel connection, and there is commercial value.

PL

Przedstawiono możliwości wytwarzanie trzyfazowego i piezoelektrycznego generator w nanotechnologii. Przy typowych wibracjach materiały piezoelektryczne mogą służyć jako generatory napięcia i prądu. Przedstawiono możliwości połączenia obu generatorów w jeden system.

4

New models of fracture in solids at meso- and nanoscales

Wnuk M.

Czasopismo Techniczne. Mechanika

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2010

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R. 107, z. 4-M

167-180

EN

Novel properties of the present cohesive crack models provide a better insight and an effective tool to explain multiscale nature of fracture process and the associated transitions from macroto meso- and nano-levels of material response to deformation and fracture. Fracture testing of materials with cementitious bonding such as concrete and certain types of ceramics demonstrates that fractal cracks are commonly observed. In the limit of vanishing fracture quantum and/ or reduced degree of fractality the quantized cohesive model of a fractal crack, as presented here, reduces to the well-known classic models of Dugdale-Barenblatt or to the linear elastic fracture mechanics or the quantized fracture mechanics theories. Therefore, the basic concepts of linear elastic fracture mechanics, quantized fracture mechanics and fractal geometry are all incorporated into the present theory.

PL

Nowe właściwości materiału oraz jego zachowania w procesie deformacji i pękania zostały opisane teoretycznie na podstawie dyskretnego modelu kohezyjnego szczeliny, uwzględniającego również geometrię fraktalną. Okazuje się, że dla makroszczelin różnice między nowym opisem oraz klasycznymi teoriami zniszczenia, takimi jak teoria Griffitha oraz LEFM (liniowo-sprężysta mechanika zniszczenia), nie są zbyt istotne. Natomiast w zakresie nanoszczelin, kiedy długość szczeliny jest porównywalna z kwantum propagacji a[0], różnice te są istotne. Uwzględnienie geometrii fraktalnej oraz dyskretnej natury propagacji szczeliny ma znaczący wpływ na końcowe rezultaty teorii dotyczącej tzw. wytrzymałości rezydualnej materiału niedoskonałego zawierającego początkowe defekty.

5

Nanoinżyneria rolnicza

Rzeźnik Cz.

Journal of Research and Applications in Agricultural Engineering

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2009

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Vol. 54, nr 2

91-94

PL

Określenia poprzedzone przedrostkiem nano początkowo dotyczyły tylko różnych jednostek miar i określały, że jednostka z przedrostkiem nano stanowi 10-9 jednostki podstawowej. Obecnie pojawiają się one w wielu dziedzinach. Rozpoczęło się od nanotechnologii a potem były nanomedycyna, nanonauka itp. Przedrostek ten określa obszary wymagające dużych dokładności. Inżynieria rolnicza jako dyscyplina naukowa też będzie rozwiązywać wiele problemów naukowych w obszarze nano, stąd tytuł pracy nanoinżynieria rolnicza. Przedstawiono w niej istotę nano, efekty płynące z jej wykorzystania oraz potencjalne obszary zastosowań w inżynierii rolniczej.

EN

Definitions with the prefix nano initially regarded only to measure units and defined, that the size preceeded by it makes up 10-9 the basic individual. Nowadays they appear in many fields of the science. It began front nanotechnology and afterwards it was used in nanomedicine and nanoscience etc. This prefix defines the fields in which large exactitudes are used. Agricultural engineering as the scientific discipline can also solve many scientific problems in the area nano, front here the title of the work agricultural nanoengineering. Essence of nano, effects flowing from her utilization and the potential areas of its use in agricultural engineering were introduced in the work.