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Gurdip Singh

Bio: Gurdip Singh is an academic researcher from Indian Institute of Technology Roorkee. The author has contributed to research in topics: Thermal decomposition & Halide. The author has an hindex of 1, co-authored 5 publications receiving 21 citations.

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TL;DR: Three salts of phenylenediammonium diperchlorate have been prepared and characterized by X-ray crystallography and the kinetics of thermal decomposition was evaluated by model fitting and isoconversional methods using TG data.
Abstract: Three salts of phenylenediammonium diperchlorate have been prepared and characterized by X-ray crystallography. Their thermal decomposition has been studied by thermogravimetry (TG), differential thermal analysis (DTA), and explosion delay (DE) measurements. The kinetics of thermal decomposition was evaluated by model fitting and isoconversional methods using TG data. The oxidation-reduction reactions near the surface of thermolysing perchlorates may be responsible for the decomposition followed by explosion. The possible pathways of thermolysis have also been proposed.

19 citations

01 Aug 2000
TL;DR: In this paper, the role of the proton transfer mechanism in the thermal decomposition of ammonium cation has been investigated and the th e rm al decomposition pathways have also been proposcd.
Abstract: Ring substituted arylammonium fluorides ( RSAF) have been prepared and characterised. The thermal decomposition of these sal ts has been investigated by thennoanalytical techniques and kinetic parameters are evaluated. The th e rm al decomposition pathways have also been proposcd. The proton transfer mechanism ha s been postulated to play an important role in the thermal decomposition of large number of ammonium salts. Erdey et 01 .1.2 have investigated twenty six ammonium sa lt s deri vato graphi call y and results have been ex plained by app lyin g acid-base theory. The decomposition processes have also been reported whi ch are on the basis of thermograms. The formation of intermediate has been suggested where plateaux occur on TG curves. The th ermal decomposition of NH4F invo lv e the following reaction pat hway. 2NH.\F .. NfLF.HF + NH3 The intermediate ammonium hydroge n flu orid e begins to decompose slowly at this temperature but decomposition rate is hi ghest at 255 D C and NH3 and HF are report ed to be evolved. Therefore, it was thought approp ri ate to invest igate the role of rin g­ su bsti tuted phenyl group s, when sub stituted for hydrogen atom of ammonium cation. A lot of work has already been reponed on the preparation , characterisation and thermolysis of I . . 3-5 I I CHI I I 9-1 ~ ary ammon ium nttrates , perc 1 orates , su plates -, ch lorid es '3 ,,') and bromjdes '5 . ' 6 . These sa lt s have been fo und to dissociate to parent arylamine and acid mol ec ul es [H 2SO.j, HN03, HClO.\, HCI , HBr] and proton transfer [N-H bond heterolysis] seems to be th e primary and rate controllin g step. A large number of ring substituted arylammonium fluorides [RSAF] . have been prepared and characterised. Their th ermal decomposition ha s also been in ves ti ga ted Llsin g TG and simultaneous TG-DT A in ord er to understand their mechanism of decomposition . *For corrcspondencc Experimental Procedure Aniline (Quali gens), Ill- toluidine (Johnson Chemical Limited), p-toluidine (B DH), m-<:hl oroanilin e (CDH), p-<:hloroaniline (CDH), m-aminobenzoic acid (Merck), p-aminobenzoic ac id (S ISCO), lIl-nitroanilin e (Robert John son), p-nitroaniline (Johnson Chemical Co.) were purified by usual method s. Hydrofluoric ac id (CDH), silica gel G for TLC (Quali gens) we re used as rece ived. Preparation and characterisation of mono ring substitut ed arylammonium fluorides (RSAF)

1 citations

01 Aug 2010
TL;DR: Di-(2,4,6-trimethylanilinium) sulphate was synthesized by reaction of 2, 4, 6, trimethylinium with concentrated sulphuric acid at room temperature as discussed by the authors.
Abstract: Di-(2,4,6-trimethylanilinium) sulphate [2,4,6-TMAS] was synthesized by reaction of 2,4,6-trimethylaniline with concentrated sulphuric acid at room temperature. The crystal structure of this salt was determined using single crystal X-ray diffraction. It crystallizes in orthorhombic space group Pna21, a= 7.7115(1) Å, b= 30.3746 (6) Å, c=16.9251 (3)Å , α=β=γ [°]=90°, V=3964.43 (12)A and Z=8. The structure contains 2,4,6-trimethylanilinium ions that share vertices through intermolecular Hbonds with sulphate ions and a water molecule. Notably thermal and microwave heatings of di-(2,4,6TMA)S have afforded 3-amino-2,4,6-trimethylbenzenesulphonic acid (3-A-2,4,6-TMBSA) with release of a molecule of amine and water. It has been suggested that the proton transfer from anilinium to SO4 2ion is a primary and rate controlling step. Further di-(2,4,6-TMA)S and 3-A-2,4,6-TMBSA were characterized by infrared, mass spectrometry, elemental and thermogravimetricdifferential scanning calorimetric (TG-DSC) analyses. The mean value for the energy of activation (83.0 kJ mol) for the conversion of di-(2,4,6-TMA)S to 3-A-2,4,6-TMBSA has been determined from isothermal thermogravimetry data.

1 citations

01 Jan 2000
TL;DR: A review of the mechanistic aspects of thermolysis of nitrate, perchlorate, sulfate, chloride of alkyl and arylamines has been described critically in the present review taking into account the role of proton transfer reactions.
Abstract: Introduction The decomposition of ammonium salts has been explained on the basis of the high temperature acid­ base theoryl-3 . The base strength of the aniop increases with the rise in temperature until it reaches the base strength of the ammonia molecule. At this temperature, the anion base removes the proton froin the ammonium cation. The weaker the anion base, the higher would be the decomposition temperature. Many ammonium salts have been investigated with the help of thermoanalytical techniques and results have been explained2• Plateaux have been found to occur in TG curves which clearly indicates the formation of intermediates. Experimental weight losses agreed well in most cases with the theoretic�l losses expected for the formation of such compounds. Thermolysis of inorganic ammonium salts of H3P04, H2S04, HCI04, HCI, HI, HF, HBr, AcOH has been studied extensively and reported in a good number of publications4-1� Thermolysis of alkyl and arylammonium salts of some of the acids have . been undertaken in the last decade and most of the work is available in the ' literature in scattered manner, · and hence, it was thought to review these studies. The mechanistic aspects of thermolysis of nitrate, perchlorate, sulfate, chloride of alkyl and arylamines have been described critically in the present review taking into account the role of proton transfer reactions.

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TL;DR: In this article, Nanocrystalline transition metal oxides (NTMOs) have been successfully prepared by three different methods: novel quick precipitation method, surfactant mediated method and reduction of metal complexes with hydrazine as reducing agent (Mn2O3).
Abstract: Nanocrystalline transition metal oxides (NTMOs) have been successfully prepared by three different methods: novel quick precipitation method (Cr2O3 and Fe2O3); surfactant mediated method (CuO), and reduction of metal complexes with hydrazine as reducing agent (Mn2O3). The nano particles have been characterized by X-ray diffraction (XRD) which shows an average particle diameter of 35 – 54 nm. Their catalytic activity was measured in the thermal decomposition of ammonium perchlorate (AP). AP decomposition undergoes a two step process where the addition of metal oxide nanocrystals led to a shifting of the high temperature decomposition peak toward lower temperature. The kinetics of the thermal decomposition of AP and catalyzed AP has also been evaluated using model fitting and isoconversional method.

109 citations

Journal ArticleDOI
TL;DR: In this paper, the synthesis of Cu nanoparticles by reducing CuSO 4 with hydrazine in ethylene glycol under microwave irradiation, has been described, and the catalytic activity, of CU nanoparticles on thermal decomposition of ammonium perchlorate (AP), composite solid propellants (CSPs) using thermogravimetry (TG), differential scanning calorimetry(DSC) have been measured.

66 citations

Journal ArticleDOI
TL;DR: In this article, a coprecipitation method was used to obtain the average particle size by using Scherrer's equation for BTMF nanocrystals of formula MFe2O4 (M=Cu, Co, Ni) and characterized by X-ray diffraction.
Abstract: Binary transition metal ferrite (BTMF) nanocrystals of formula MFe2O4 (M=Cu, Co, Ni) were prepared by the coprecipitation method and characterized by X-ray diffraction (XRD). XRD patterns gave average particle size by using Scherrer's equation for CuFe2O4 (CuF), CoFe2O4 (CoF), and NiFe2O4 (NiF) as 39.9, 27.3, and 43.8 nm, respectively. The catalytic activity measurements on the thermal decomposition of ammonium perchlorate (AP) were carried out by using thermogravimetry (TG), differential thermal analysis (DTA), and ignition delay studies. Isothermal TG data up to a mass loss of 45% have been used to evaluate kinetic parameters by using model fitting as well as isoconversional method. The order of catalytic activity was found to be:

64 citations

Journal ArticleDOI
TL;DR: In this paper, the synthesis of nanocrystalline cadmium oxide (CdO) and its characterization by X-ray diffraction (XRD) and transmission electron microscopy (TEM) were reported.
Abstract: In this paper, we report the synthesis of nanocrystalline cadmium oxide (CdO) and its characterization by X-ray diffraction (XRD) and transmission electron microscopy (TEM). Its catalytic activity was investigated on the thermal decomposition of 1,2,5,7-tetranitro-1,3,5,7-tetraazacyclooctane (HMX), ammonium perchlorate (AP), hydroxyl terminated polybutadiene (HTPB) and composite solid propellants (CSPs) using thermogravimetric analysis (TG), simultaneous thermogravimerty and differential scanning calorimetry (TG–DSC) and ignition delay measurements. Kinetics of thermal decomposition of AP + CdO has also been investigated using model free (isoconversional) and model-fitting approaches which have been applied to data for isothermal TG decomposition. All these studies show enhancement in the rate of decomposition of AP, HTPB and CSPs but no effect on HMX. The burning rate of CSPs has also been found to be increased with CdO nanocrystals.

34 citations

Journal ArticleDOI
TL;DR: CdFe2O4 and Cd nanocrystals were synthesized by wet chemical and hydrazine reduction methods, respectively, and characterized by XRD and TEM as mentioned in this paper.

28 citations