Effect of Nano-CuO on Luminous Intensity of Pyrotechnics Composite Containing KClO4 and Al

2012 ◽  
Vol 217-219 ◽  
pp. 669-672
Author(s):  
Shu Hong Ba ◽  
Zhe Zhang ◽  
Ming Hui Yan ◽  
Zhe Xing Sun ◽  
Xin Peng Teng
Keyword(s):  
Thermal Decomposition ◽  
Spherical Shape ◽  
Decomposition Temperature ◽  
Luminous Intensity ◽  
Precipitation Method ◽  
Thermal Decomposition Temperature ◽  
Direct Precipitation ◽  
Analysis Instrument ◽  
Average Size ◽  
Direct Precipitation Method

Nano-CuO had been successfully synthesized by using direct precipitation method. The prepared sample was characterized by XRD. The luminous intensities of pyrotechnics composite containing KClO4, Mg and nano-CuO were measured. The catalysis of CuO nanocrystal on KClO4 was investigated by thermal analysis instrument. The results show that the average size of nano-CuO is 19 nm and has spherical-shape. When nano-CuO is added into the pyrotechnics composites containing KClO4 and Al, it can improve the igniting and burning performance. The luminous intensity of trinary pyrotechnics composite is also greatly increased. On the other hand, nano-CuO can make thermal decomposition temperature of KClO4 to decrease 97.7 °C, the decalescence amount also reduced to 79.07 J/g. It is obviously that nano-CuO has strong catalysis to KClO4 thermal decomposition. The conclusion is consistent with the measure results of luminous intensity.

Preparation of Nanoscale CuO Powders

2010 ◽  
Vol 113-116 ◽  
pp. 1770-1773 ◽  
Author(s):  
Xi Hua Zhao ◽  
Min Xu
Keyword(s):  
Raw Materials ◽  
Precipitation Method ◽  
Optimum Conditions ◽  
Muffle Furnace ◽  
Factors Affecting ◽  
Direct Precipitation ◽  
Average Grain Size ◽  
Scherrer Formula ◽  
Average Size ◽  
Direct Precipitation Method

Cu(OH)2 precursor was synthesized by direct precipitation method and CuSO4 and NaOH were used as raw materials. Then, Cu(OH)2 precursor was calcined in muffle furnace at 400°C for 2h in order that CuO particle was obtained. Through the analysis of the factors affecting the CuO, the paper determined the optimum conditions for the synthesis of nano-CuO with the direct-precipitation method. Then the paper analyzed phase composition and crystal structure of samples using XRD and calculated the average grain size of samples by Scherrer formula, and observed and analyzed by TEM to characterize the morphology and particle size of samples. The optimum precipitation conditions are as follows: when the precipitation agent is 3.2:1, reaction time 40min and precipitant concentration 0.6mol.L-1. The average size of CuO particle prepared under the conditions is 18nm and the yield is 96%.

scholarly journals Investigating the Kinetics of the Thermolysis of 3-nitro-2,4-dihydro-3H-1,2,4-triazol-5-one (NTO) and Reduced Size NTO the Presence of Cobalt Ferrite Additive

2021 ◽  
Author(s):  
pragnesh N Dave ◽  
Ruksana Sirach ◽  
Riddhi Thakkar ◽  
M P Deshpande
Keyword(s):  
Thermal Decomposition ◽  
Energetic Materials ◽  
Cobalt Ferrite ◽  
Simultaneous Thermal Analysis ◽  
Isoconversional Methods ◽  
Decomposition Temperature ◽  
Precipitation Method ◽  
Thermal Decomposition Temperature ◽  
Highly Sensitive ◽  
Co Precipitation

Abstract Less sensitive high energetic materials (HEMs) are explored as a potential replacement of highly sensitive HEMs in propellants, and explosive applications. More research have been devoted to improve the thermal decomposition of such a less sensitive HEMs. Nanosize Cobalt ferrite (CoF) has been successfully synthesized using the co-precipitation method. Synthesis of less sensitive HEM 3-nitro-2,4-dihydro-3H-1,2,4-triazol-5-one(NTO) and its size reduction using solvent-antisolvent method is successfully achieved. Effect of 5 % by weight CoF on the thermolysis of NTO and NTO with reduced size (r-NTO) has been studied using the simultaneous thermal analysis. Three isoconversional methods namely Flynn Ozawa Wall, Kissinger-Akahira-Sunose (KAS), and Starink are employed to evaluate the kinetic parameter of NTO, and r-NTO in the presence of CoF additive. It was found that both the addition of CoF as well as reducing size of NTO can decrease the thermal decomposition temperature of NTO, the later decreasing the thermal decomposition temperature to a good extent compared to former. However, the kinetic study using isoconversional methods suggested that in the presence of CoF additive, the activation energy of both NTO as well as n-NTO is increased.

Synthesis of ZnO Nanoparticles by Direct Precipitation Method

2011 ◽  
Vol 380 ◽  
pp. 335-338 ◽  
Author(s):  
Li Juan An ◽  
Jun Wang ◽  
Tie Feng Zhang ◽  
Han Lin Yang ◽  
Zhi Hui Sun
Keyword(s):  
Zno Nanoparticles ◽  
Spherical Shape ◽  
Zinc Nitrate ◽  
Precipitation Method ◽  
Thermal Gravimetric ◽  
Direct Precipitation ◽  
Transmission Electron ◽  
Ft Ir ◽  
Tg And Dtg ◽  
Direct Precipitation Method

In this study, Zinc oxide (ZnO) nanoparticles were prepared using Zinc nitrate (Zn(NO3)2) and Ammonium carbonate ((NH4)2CO3) in aqueous solutions with proper concentration by a direct precipitation method. The properties of ZnO nanoparticles synthesized were characterized by the thermal gravimetric (TG) and differential thermal gravimetric (DTG), Fourier transform infrared (FT-IR) spectroscopy, X-ray diffraction (XRD), and transmission electron microscopy (TEM), respectively. Both TG and DTG curves of the precursor precipitates show that no further mass loss and thermal effect were observed above the temperature 450°C. The FT-IR results indicated that the precursor of ZnO nanoparticles was zinc hydroxy carbonate. The XRD results show that the prepared ZnO nanoparticles were pure wurtzite structures. TEM photographs demonstrated that ZnO nanoparticles were of a pseudo-spherical shape with an average crystal size of about 65 nm.

One-step growth of isoreticular luminescent metal–organic frameworks on cotton fibers

RSC Advances ◽  
2015 ◽  
Vol 5 (20) ◽  
pp. 15198-15204 ◽  
Author(s):  
R. R. Ozer ◽  
J. P. Hinestroza
Keyword(s):  
Metal Organic Frameworks ◽  
Precipitation Method ◽  
Cotton Fibers ◽  
Direct Precipitation ◽  
Metal Organic ◽  
One Step ◽  
Lanthanide Metal ◽  
Step Growth ◽  
Direct Precipitation Method ◽  
Temperature Water

A series of isoreticular lanthanide metal–organic frameworks, Ln-MOFs (Ln = Eu, Gd, and Tb), were directly grown on cotton fibers using a room temperature water-based direct precipitation method.

Transesterification of Jatropha Oil to Biodiesel by Using Catalyst Containing Ca(C3H7O3)2 as a Solid Base Catalyst

2013 ◽  
Vol 666 ◽  
pp. 93-102 ◽  
Author(s):  
Chang Jun Li ◽  
Zhi Wei Huang ◽  
Yu Jie He ◽  
Dong Zhou ◽  
Cheng Du ◽  
...  
Keyword(s):  
Fatty Acid Methyl Esters ◽  
Methyl Esters ◽  
Precipitation Method ◽  
Molar Ratio ◽  
Solid Base ◽  
Jatropha Oil ◽  
Direct Precipitation ◽  
Acid Methyl ◽  
Direct Precipitation Method ◽  
C Nmr

An direct precipitation method of Calcium glyceroxide Ca(C3H7O3)2 was proposed. The prepared Ca(C3H7O3)2 was effective in transesterification of Jatropha oil into fatty acid methyl esters (FAME). The Ca(C3H7O3)2 catalysts were characterized by using XRD, solid state 13C-NMR, FTIR, and Hammett indicator. The influence of various reaction variables on the conversion was investigated. Under a condition of methanol/oil molar ratio of 9:1, a catalyst amount of 4 wt %, reaction time of 1.5 h, and reaction temperature of 65 °C, over 95% of biodiesel yield was obtained.

scholarly journals Hydrothermal Synthesis of Hematite Nanoparticles Decorated on Carbon Mesospheres and Their Synergetic Action on the Thermal Decomposition of Nitrocellulose

Nanomaterials ◽  
2020 ◽  
Vol 10 (5) ◽  
pp. 968 ◽  
Author(s):  
Abdenacer Benhammada ◽  
Djalal Trache ◽  
Mohamed Kesraoui ◽  
Salim Chelouche
Keyword(s):  
Activation Energy ◽  
Thermal Decomposition ◽  
Analytical Techniques ◽  
Decomposition Reaction ◽  
Decomposition Temperature ◽  
Heating Rates ◽  
Scanning Calorimetry ◽  
Nano Catalyst ◽  
Average Size ◽  
A Minor

In this study, carbon mesospheres (CMS) and iron oxide nanoparticles decorated on carbon mesospheres (Fe2O3-CMS) were effectively synthesized by a direct and simple hydrothermal approach. α-Fe2O3 nanoparticles have been successfully dispersed in situ on a CMS surface. The nanoparticles obtained have been characterized by employing different analytical techniques encompassing Fourier transform infrared (FTIR) spectroscopy, Raman spectroscopy, X-ray diffraction (XRD) and scanning electron microscopy (SEM). The produced carbon mesospheres, mostly spherical in shape, exhibited an average size of 334.5 nm, whereas that of Fe2O3 supported on CMS is at around 80 nm. The catalytic effect of the nanocatalyst on the thermal behavior of cellulose nitrate (NC) was investigated by utilizing differential scanning calorimetry (DSC). The determination of kinetic parameters has been carried out using four isoconversional kinetic methods based on DSC data obtained at various heating rates. It is demonstrated that Fe2O3-CMS have a minor influence on the decomposition temperature of NC, while a noticeable diminution of the activation energy is acquired. In contrast, pure CMS have a slight stabilizing effect with an increase of apparent activation energy. Furthermore, the decomposition reaction mechanism of NC is affected by the introduction of the nano-catalyst. Lastly, we can infer that Fe2O3-CMS may be securely employed as an effective catalyst for the thermal decomposition of NC.

Preparation of Magnesium Carbonate Whisker by Using Magnesite Tailings

2010 ◽  
Vol 654-656 ◽  
pp. 2022-2024
Author(s):  
Nan Wang ◽  
Yue Yuan Li ◽  
Hong Wei Ni
Keyword(s):  
Thermal Decomposition ◽  
Aspect Ratio ◽  
Magnesium Carbonate ◽  
Decomposition Temperature ◽  
Magnesium Salt ◽  
Thermal Decomposition Temperature ◽  
Stirring Intensity

Magnesium carbonate whisker was prepared by thermal decomposition of Mg(HCO3)2 solution that was prepared through hydration and carbonation of light burnt magnesia derived from magnesite tailings. The effects of thermal decomposition conditions on the morphology of magnesium carbonate crystal were investigated. Magnesium carbonate whiskers were successfully prepared when a kind of soluble magnesium salt was added, and magnesium carbonate whiskers with the length of 20 to 60μm and aspect ratio of 10~20 were obtained under the condition of 50 °C thermal decomposition temperature and 200 rpm stirring intensity.

Measurement of Thermal Decomposition Temperature and Rate of Sodium Hydride

2020 ◽  
Author(s):  
Munemichi Kawaguchi
Keyword(s):  
Thermal Decomposition ◽  
Mass Loss ◽  
Heating Temperature ◽  
Fission Products ◽  
Sodium Hydride ◽  
Decomposition Temperature ◽  
Cold Trap ◽  
Thermal Decomposition Temperature ◽  
Heating Rates ◽  
Fundamental Research

Abstract In decommissioning sodium-cooled fast reactors, the operators can be exposed to radiation during dismantling of cold trap equipment (C/T). The C/T is higher dose equipment because the C/T trapped tritium of fission products during the operation to purify the sodium coolant. In this study, thermal decomposition temperature and rate of sodium hydride (NaH) were measured as a fundamental research for development of “thermolysis” process prior to the dismantling. We measured the thermal decomposition temperature and rate using NaH powder (95.3%, Sigma-Aldrich) in alumina pan with ThermoGravimetry-Differential Thermal Analysis (TG-DTA) instrument (STA2500 Regulus, NETZSCH Japan). The heating rates of TG-DTA were set to β = 2.0, 5.0, 10.0 and 20.0 K/min. The DTA showed endothermic reaction and the TG showed two-steps mass-loss over 580K. This first-step mass-loss was consistent with change of chemical composition of the NaH with heating (NaH → Na+1/2H2). The thermal decomposition temperature and rate were obtained from the onset temperature of the mass-loss and the simplified Kissinger plots, respectively. Furthermore, we set to the thermal decomposition temperature of around 590K, and the mass-loss rates were measured. As a result, over 590K, the thermal decomposition occurred actively, and showed good agreement with the estimation curves obtained by the simplified Kissinger plots. The thermal decomposition rate strongly depended on the heating temperature.

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