[Cu(TO)2(H2O)4](PA)2的制备、结构表征和热分解机理研究

[Cu（TO）2（H2O）4]（PA）2 was prepared by the reaction of aqueous 1,2,4-triazol-5-one （TO） solution with the solution of copper picrate Cu（PA）2 and characterized by elemental analysis, FT IR and X-ray powder diffraction analysis. The title complex has been studied by means of TG-DTG and DSC under conditions of linear temperature increase. The thermal decomposition residues were examined by FT IR analysis. Thermal decomposition mechanism of the title complex was proposed. In the temperature range of 30-680 ℃, the thermal decomposition process was composed of four major stages. The first stage was an endothermic process with the loss of four coordination water molecules. Since the dehydration product was unstable, when it was heated, it would be decomposed much more easily. The second stage was composed of an acute endothermic process and a continued strong exothermic process and the main decomposed residues were CuCO3, Cu（NCO）2 and polymers during this stage. The third stage was a sharp exothermic process, which resulted from the decomposition of the polymer. After the forth stage, the final decomposed residues were certainly copper oxide. The Arrhenius parameters have been also studied on the dehydration process and the first-step exothermic decomposition of [Cu（TO）2（H2O）4]（PA）2 using Kissinger＇s method and Ozawa-Doyle＇s method. The results using both methods were consistent with each other. The Arrhenius equation can be expressed as in k=24.0-179.8 × 10^3/RT for the dehydration process and in k= 16.7-206.0 × 10^3/RT for the first-step exothermic decomposition, on the basis of the average of Ea and In A through the two methods.     

鬼臼毒素及其衍生物热分解反应的动力学研究

The thermal behavior and thermal decomposition kinetic parameters of podophyllotoxin （1） and 4 derivatives, picropodophyllin （2）, deoxypodophyllotoxin （3）, fl-apopicropodophyllin （4）, podophyllotoxone （5） in a temperature-programmed mode have been investigated by means of DSC and TG-DTG. The kinetic model functions in differential and integral forms of the thermal decomposition reactions mentioned above for first stage were established. The kinetic parameters of the apparent activation energy Ea and per-exponential factor A were obtained from analy- sis of the TG-DTG curves by integral and differential methods. The most probable kinetic model function of the decomposition reaction in differential form was （1- a）^2 for compounds 1-3,2/3·a^-1/2 for compound 4 and 1/2（1-a）·[-In（1-a）]^-1 for compound 5. The values of Ea indicated that the reactivity of compounds 1-5was increased in the order： 5〈4〈2〈1〈3. The values of the entropy of activation △S^≠, enthalpy of activation △H^≠ and free energy of activation △G^≠ of the reactions were estimated. The values of △G^≠ indicated that the thermal stability of compounds 1-3 with the samef（a） was increased in the order： 2〈3〈1.     

Thermal Kinetics and Decomposition Mechanism of 1-Amino-1,2,3-triazolium Nitrate

The thermal decomposition kinetics of 1-amino-l,2,3-triazolium nitrate（ATZ-NO3） was investigated by non-isothermal TG-DTG at various heating rates（2,5,10,15 and 20 ℃/min）.The results show that the thermal decomposition of ATZ-NO3 consists of two stages corresponding to the losing of nitrate anion,substituent group and the splitting of triazole ring respectively.The kinetic triplets of the two stages were described by a three-step method.First,the differential Kissinger and intergral Ozawa methods were used to calculate the apparent activation energies（E） and pre-exponential factors（A） of the two decomposition stages.Second,two calculation methods（intergral （S）atava-（S）esták and differential Achar methods） were used to obtain several probable decomposition mechanism functions.Third,three judgment methods（average,double-extrapolation and Popescu methods） were used to confirm the most probable decomposition mechanism functions.Both reaction models of the two stages were randominto-nucleation and random-growth mechanisms with n=3/2 for the first stage and n=1/3,m=3 for the second stage.The kinetic equations for the two decomposition stages of ATZ-NO3 may be expressed as da/dt=1013.60·e-128970/RT（1-α）[-1n（1-α）]-1/2 and da/dt=1011.41·e-117370/RT（1-α）[-1n（1-α）]-2/3.The thermodynamic parameters including Gibbs free energy of activation（△G≠）,entropy of activation（△S≠） and enthalpy of activation（△H≠）,for the thermal decomposition reaction were also derived.     

Evaluation of Thermal Hazard of Composite Modified Double-base Propellant by Microcalorimetery Method

<正>The thermal decomposition behavior of composite modified double-base(CMDB) propellant containing cyclotrimethylene trinitramine(RDX) was studied via a Calvet microcalorimeter at five different heating rates.The activation energy(E) and the pre-exponential factor(A) of two obvious exothermic processes were obtained by Kissinger's method and Ozawa's method.The entropy of activation(△A~≠),the enthalpy of activation(△H~≠),and the free energy of activation(△G~≠) of the first stage were calculated.To evaluate the thermal hazard of the RDX-CMDB propellant, the critical temperature of thermal explosion(T_b),the self acceleration decomposition temperature(T_(SADT)),the adiabatic decomposition temperature increment(△T_(ad)) and the time-to-explosion of adiabatic system(t) were presented as 145.3℃,138.15℃,1634 K and 583.71 s(n=0) and 586.28 s(n=1),respectively.     

Synthesis and Thermal Decomposition Kinetics of the Complex of Samarium p-Methylbenzoate with 1 ,10-Phenanthroline

The complex [Sm（p-MBA）3phen]2 （p-MBA, p-methylbenzoate; phen, 1,10-phenanthroline） was prepared and characterized by elemental analysis, IR and UV spectra. The thermal decomposition process of [Sm（pMBA）3phen]2 was studied under a static air atmosphere by TG-DTG and IR techniques. Thermal decomposition kinetics was investigated employing a newly proposed method, together with the integral isoconversional non-finear method. Meanwhile, the thermodynamic parameters （AH#, △G# and AS#） were also calculated. The lifetime equation at mass-loss of 10% was deduced as In r=-24.7825＋ 18070.43/T by isothermal thermogravimetric analysis.     

1，4-双(1′-苯基-3′-甲基-5′-氧代吡唑-4′-基)丁二酮-(1，4)合双铜(Ⅱ)配合物的合成、表征、非等温热分解反应动力学及电化学性质

The paper reported the synthetic procedure and character of Copper(Ⅱ) binuclear coordination compound of 1,4-bis-(1′-phenyl-3′-methyl-5′-pyrazolone-4′)-1,4-butanedione. The non-isothermal kinetic of the thermal decomposition of the complex has been studied from the TG-DTG curves by means of the Achar et al and Coats-Redfern methods. The electrochemical characterization of the complex were studied by means of powder microelectrodes technique.     

Dehydration Kinetics of Zinc Phosphate Tetrahydrate α-Zn3（PO4）2·4H2O Nanoparticle

TG-DTG technique and Harcourt-Esson integrated equation were used to study the dehydration process of zinc phosphate tetrahydrate α-Zn3（PO4）2·4H2O nanoparticle and its thermal decomposition kinetics. The results show that there are three stages of dehydration between 300 and 800 K during the thermal decomposition of α-Zn3（PO4）2·4H2O nanoparticle. The first stage is controlled by chemical reaction with an activation energy of 69.48 kJ·mol^-1 and a pre-exponential factor of 1.77×10^6 s^-1. The second is controlled by nucleation and growth with an activation energy of 78.74 kJ·mol^-1 and a pre-exponential factor of 5.86×10^9 s^-1. The third is controlled by nucleation and growth with an activation energy of 141.5 kJ·mol^-1 and a pre-exponential factor of 1.01×10^12 s^-1. The kinetic compensative effects not only exist in Arrhenius equation but also in Harcourt-Esson equation. Activation energy E is dependent on both the decomposition fraction α and temperature T.     

The Thermal Decomposition of Calcium Carbonate

The thermal decomposition reaction of calcium carbonate is a typical thermal decompo- sition reaction of the solid state. A great deal of studies on this reaction have been performed by previous investigators. This paper reports a procedure for estimating the non-isothermal kinetic parameters and the reaction mechanism of calcium carbonate.TG-DTG experiments were carried out on a LCT-1 model thermobalance and a WF-1 model differentiator with a TG-DTA-DTG simultaneous device. The size of…     

Preparation of nanometer FeCuP alloy and its application in decomposition of PH3

A new ternary Fe-based alloy catalyst FeCuP applied to decompose PH_3 was prepared with low-cost material by chemical reduction deposition method.The properties of it were characterized by XRD,ICP and SEM.Its catalytic activity on the decomposition of PH_3 and the decomposition conditions were studied.FeCuP alloy exhibits high thermal stabilities and high catalytic activity.Using it as catalyst,the decomposition temperature of phosphine decreases from over 800℃to 400-500℃.The decomposition rate of phosphine achieved 100%.     

Non-isothermal Decomposition Mechanism and Kinetics of LiClO4 in Nitrogen

The non-isothermal decomposition kinetics of LiClO4 in flow N2 atmosphere was studied.TG-DTA curves show that the decomposition proceeded through two well-defined steps below 900°C,and the mass loss was in agreement with the theoretica1 value.XRD profile demonstrates that the product of the thermal decomposition at 500°C is LiCl.For the decomposition kinetics study,the activation energies calculated with the Friedman method were considered as the initial values for non-linear regression and were used for verifying the correctness of the fitted models.The decomposition process was fitted by a two-step consecutive reaction:extended Prout-Tompkins equation[Bna,f (α) is (1?α)nα a] followed by a 1th order reaction(F1).The activation energies were (215.6±0.2) and (251.6±3.6) kJ/mol,respectively.The exponentials n and a for Bna reaction were (0.25±0.05) and (0.795±0.005),respectively.The reaction types and activation energies were in agreement with those obtained from the isothermal method,but the exponentials were optimized for better fitting and prediction.     

Non-isothermal Kinetics of the Thermal Decomposition of 3-Nitro-1,2,4-triazol-5-one Magnesium Complex

Introduction3 Nitro 1,2 ,4 triazol 5 one (NTO)metalcomplexeshavemanyspecialstructuresandsomepotentialusesinammunition .1 4 Wepreviouslypreparedanddeterminedthecrystalstructureofitsmagnesiumcomplex ,5andinthispaper ,wediscusseditsthermalbehaviorbyDSCandTG/DTGtechniquesandstudieditsnon isothermalkineticsbythemeansoftheKissingermethod ,theOzawamethod ,thedifferentialmethodandtheintegralmethod .ExperimentalSample[Mg(H2 O) 6 ](NTO) 2 ·2H2 Owaspreparedasfollows :AcalculatedamountofMg(OH…     

The Non‐Isothermal Decomposition Kinetics of NaNTO·H2O and the Relationship between its Structure and Properties

NaNTO·H₂O was prepared by mixing 3‐nitro‐1,2,4‐triazol‐5‐one (NTO) aqueous solution and sodium hydroxide aqueous solution. Its thermal decomposition and kinetics were studied under non‐isothermal conditions by DSC and TG/DTG methods. The kinetic parameters were obtained from analysis of the DSC and TG/DTG curves by the Kissinger method, the Ozawa method, the differential method and the integral method. The most probable mechanism function for the thermal decomposition of the first stage was suggested by comparing the kinetic parameters. The critical temperature of thermal explosion (T_b) was 240.93 °C. The theoretical investigation on the structure unit of the title compound was carried out by DFT‐B3LYP/CEP‐31G methods; atomic net charges and the population analysis were discussed.     

Synthesis and thermal decomposition reaction kinetics of complexes of [Sm2(m‐ClBA)6(phen)2] · 2H2O and [Sm2(m‐BrBA)6(phen)2] · 2H2O

Complexes of [Sm₂(m‐ClBA)₆(phen)₂] · 2H₂O and [Sm₂(m‐BrBA)₆(phen)₂] · 2H₂O (m‐ClBA = m‐chlorobenzoate, m‐BrBA = m‐bromobenzoate, and phen = 1,10‐phenanthroline) were prepared and characterized by elemental analysis and IR spectra. The thermal decomposition processes of the two complexes were studied by means of TG–DTG and IR techniques. Their thermal decomposition kinetics were investigated from the analysis of the TG and DTG curves by jointly using a new method proposed by us and a newly nonlinear isoconversional integral method. © 2006 Wiley Periodicals, Inc. Int J Chem Kinet 39: 67–74, 2007     

Thermal decomposition of barium(II) tetraphenylborate

Barium(II) tetraphenylborate, Ba(Bph₄))₂·4H₂O was prepared, and its decomposition mechanism was studied by means of TG and DTA. The products of thermal decomposition were examined by means of gas chromatography and chemical methods. A kinetic analysis of the first stage of thermal decomposition was made on the basis of TG and DTG curves and kinetic parameters were obtained from an analysis of the TG and DTG curves using integral and differential methods. The most probable kinetic function was suggested by comparison of kinetic parameters. A mathematical expression was derived for the kinetic compensation effect.     

Decomposition of Cyclohexyl-t-butyl-Dimethylammonium Tetraphenylborate: Synthesis and kinetics

A new compound cyclohexyl-t-butyldimethylammonium tetraphenylborate, [C₆H₁₁N(CH₃)₂(C(CH₃)₃)]BPh₄ has been prepared, and its decomposition mechanism was studied by TG. The IR spectra of the products of thermal decomposition were examined at every stage. Kinetic analysis for the first stage of thermal decomposition process was obtained by TG and DTG curves, and kinetic parameters were obtained from the analysis of the TG-DTG curves with integral and differential equations. The most probable kinetic function was suggested by comparison of kinetic parameters.This revised version was published online in November 2005 with corrections to the Cover Date.     

Preparation and Study of Thermal Decomposition Mechanism of Zn(Thr)(AcO)_2·2H_2O

Introduction -Amino acids as additive have a wide application in medicines, foodstuff and cosmetics.1-3 The synthetic methods of amino acid have been reviewed.4,5 The solu-bility property of Zn(AcO)2-Thr-H2O (Thr=Threonine) system at 298.15 K has been investigated by the semimicro-phase equilibrium method, in which the phase region of the complex did not exist.6 The prepara-tion of Zn(Thr)SO4H2O was reported in Ref. 7∶3 times volume of acetone relative to that of water was added into t…     

Researches on Thermal Decomposition Kinetics of Composite Modified Double-base Propellants

The thermal decomposition kinetics of composite modified double‐base (CMDB) propellants with a series of contents of hexogeon (RDX) was investigated by using parameters of T_eo, T_i, T_p, T_f, T_b, T_a, E, lg A and ΔH, which were obtained from using a CDR‐4P differential scanning calorimeter (DSC) and Perkin‐Elmer Pyris 1 thermogravimetric analyzer (TG) analyses with heating rates of 5, 10, 15 and 20 K/min. Reliable activation energy was calculated using Flynn‐Wall‐Ozawa method before analyzing the thermal decomposition mechanism. TG‐DTG curves were treated with Malek method in order to obtain the reaction mechanisms. The obtained results show that the thermal decomposition mechanisms with the conversion from 0.2 to 0.4 was f(α)?1/2α, and with the conversion from 0.5 to 0.7 was f(α)?(1/4)(1?α)[?ln(1?α)]^?3.     

环丙沙星-钨硅多金属氧酸盐的制备及热分解动力学

A new polyoxometalate （CPFX·HCl）3H4SiW12O40·10H2O was prepared from ciprofloxacin hydrochloride and H4SiW12O40·nH2O in aqueous solution, and characterized by elemental analysis, IR spectra and DTA-TG-DTG techniques. The IR spectrum confirmed the presence of Keggin structure and the characteristic functional group for ciprofloxacin in the compound. The TG-DTA-DTG curves showed that its thermal decomposition was a four-step process consisting of simultaneous collapse of Keggin type structure. The residue of decomposition was the mixture of WO3 and SiO2, confirmed by X-ray diffraction and IR spectroscopy. The decomposition mechanism and nonisothermal kinetic parameters of the polyoxometalate were obtained from an analysis to the TG-DTG curves by the single scanning methods （the Achar method and Coats-Redfern method） and the multiple scanning methods （the Kissinger method, Flynn-Wall-Ozawa method and Starink method）. The results indicate that the kinetic equationswith parameters describing the thermal decomposition reaction are dα/dt=6.65×10^6[3（1-α）^2/3]e^-10495.5/T with E=87.26 kJ/mol and A=6.65×10^6 s^-1 for the second step,dα/dt=7.01×10^9（1-α）e^-18770.7/T with E=156.06 kJ/mol and A=7.01×10^9 s^-1 for the third step,dα/dt=9.77×10^43[（1-α）^2]e^-88980.0/T with E=739.78 kJ/mol and A=9.77×10^43 s^-1 for the fourth step.