Synthesis, Crystal Structure and Thermolysis of Cadmium Perchlorate Complex with Hexamethylenetetramine

The complex of cadmium perchlorate, [Cd(HMTA)2(H2O)4](ClO4)2•2H2O was synthesized by the reaction with hexamethylenetetramine (HMTA). C, H, N analyses, FT-IR, and X-ray crystallography were used to characterize the obtained complex. TG in the static air, simultaneous thermogravimetry-derivative thermogravimetry (TG-DTG), and differential scanning calorimetry (DSC) in streaming nitrogen atmosphere were evolved for thermal decay of prepared cadmium complex. To evaluate the reaction with quick warming, explosion delay measurements were attempted. The model-free isoconversional and model-fitting kinetic methodologies were applied to isothermal TG data for kinetic examination of the complex's thermal decomposition. At higher temperatures, the complex explodes to synthesize highly thermally stable residue most closely resembles cadmium oxide.

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Kinetics of Thermolysis of Nickel(II) Perchlorate Complex with n-Propylamine

Indian Journal of Materials Science ◽

10.1155/2014/787306 ◽

2014 ◽

Vol 2014 ◽

pp. 1-5 ◽

Cited By ~ 1

Author(s):

Chandra Prakash Singh ◽

Abhishek Singh

Keyword(s):

Model Fitting ◽

Isoconversional Method ◽

Nitrogen Atmosphere ◽

Molecular Formula ◽

Fast Heating ◽

Isothermal Tg ◽

Model Free ◽

Different Temperatures ◽

Explosion Delay ◽

Kinetics Of

Complex of nickel perchlorate with n-propylamine has been synthesised with molecular formula [Ni(n-pa)3(ClO4)(H2O)]ClO4. It has been characterised by elemental analysis, thermogravimetry, UV-VIS, and IR spectroscopic data. Thermal properties have been investigated by thermogravimetry (TG) in static air and by simultaneous thermogravimetry-derivative thermogravimetry-differential thermal analysis (TG-DTG-DTA) in flowing nitrogen atmosphere. Kinetics of thermolysis has been analysed applying model-fitting and model-free isoconversional method on isothermal TG data recorded at five different temperatures. To observe the response of complex towards fast heating, explosion delay time has been recorded at various temperatures and kinetics of explosion has been studied using these data.

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Synthesis, characterization and thermal decomposition of ethyl-2’-amino-5’-cyano-6’-(1H-indole-3yl)-2-oxospiro[indoline-3,4’-pyran]-3’-carboxylate under non‐isothermal condition in nitrogen atmosphere

European Journal of Chemistry ◽

10.5155/eurjchem.10.1.72-81.1812 ◽

2019 ◽

Vol 10 (1) ◽

pp. 72-81

Author(s):

Ganesan Nalini ◽

Natesan Jayachandramani ◽

Radhakrishnan Suresh ◽

Prakasam Thirumurugan ◽

Venugopal Thanikachalam ◽

...

Keyword(s):

Thermal Decomposition ◽

Kinetic Parameters ◽

Model Fitting ◽

Isothermal Condition ◽

Nitrogen Atmosphere ◽

Single Step ◽

Heating Rates ◽

Model Free ◽

Ft Ir ◽

Step Mechanism

A new compound, spiro-oxindole derivative compound namely ethyl-2ʹ-amino-5ʹ-cyano-6ʹ-(1H-indole-3yl)-2-oxospiro[indoline-3,4ʹ-pyran]-3ʹ-carboxylate (EACIOIPC) has been synthesized and characterized by microanalysis, FT-IR, mass spectrum and NMR (1H and 13C) techniques. The thermal decomposition of the compound was studied by thermogravimetric analysis under dynamic nitrogen atmosphere at different heating rates of 10, 15, 20 and 30 K/min. The kinetic parameters were calculated using model-free (Friedman’s, Kissinger-Akahira-Sunose (KAS) and Flynn-Wall-Ozawa (FWO) methods) and model-fitting (Coats and Redfern (CR)) methods. The decomposition process of EACIOIPC followed a single step mechanism as evidenced from the data. Existence of compensation effect is noticed for the decomposition of EACIOIPC. Invariant kinetic parameters are consistent with the average values obtained by Friedman and KAS in conversional methods.

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Thermal Behaviour of Candesartan Active substance and in pharmaceutical compounds

Revista de Chimie ◽

10.37358/rc.17.8.5787 ◽

2017 ◽

Vol 68 (8) ◽

pp. 1895-1902

Author(s):

Ioana Cristina Tita ◽

Eleonora Marian ◽

Bogdan Tita ◽

Claudia Crina Toma ◽

Laura Vicas

Keyword(s):

Thermal Behaviour ◽

Active Substance ◽

Pharmaceutical Research ◽

Pharmaceutical Product ◽

Nitrogen Atmosphere ◽

Pure Substance ◽

Scanning Calorimetry ◽

X Ray ◽

Ft Ir

Thermal analysis is one of the most frequently used instrumental techniques in the pharmaceutical research, for the thermal characterization of different materials from solids to semi-solids, which are of pharmaceutical relevance. In this paper, simultaneous thermogravimetry/derivative thermogravimetry (TG/DTG) and differential scanning calorimetry (DSC) were used for characterization of the thermal behaviour of candesartan cilexetil � active substance (C-AS) under dynamic nitrogen atmosphere and nonisothermal conditions, in comparison with pharmaceutical product containing the corresponding active substance. It was observed that the commercial samples showed a different thermal profile than the standard sample, caused by the presence of excipients in the pharmaceutical product and to possible interaction of these with the active substance. The Fourier transformed infrared spectroscopy (FT-IR) and X-ray powder diffraction (XRPD) were used as complementary techniques adequately implement and assist in interpretation of the thermal results. The main conclusion of this comparative study was that the TG/DTG and DSC curves, together with the FT-IR spectra, respectively X-ray difractograms constitute believe data for the discrimination between the pure substance and pharmaceutical forms.

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Crystallization kinetics mechanism investigation of sol–gel-derived NaYF4:(Yb,Er) up-converting phosphors

CrystEngComm ◽

10.1039/c7ce01265a ◽

2017 ◽

Vol 19 (34) ◽

pp. 4992-5000 ◽

Cited By ~ 7

Author(s):

C. Bartha ◽

C. E. Secu ◽

E. Matei ◽

M. Secu

Keyword(s):

Differential Scanning Calorimetry ◽

Crystallization Kinetics ◽

Sol Gel ◽

Model Fitting ◽

Crystallization Mechanism ◽

Differential Scanning Calorimetry Analysis ◽

Scanning Calorimetry ◽

Model Free

The crystallization mechanism of sol–gel-derived NaYF4:(Yb,Er) up-converting phosphors has been studied by differential scanning calorimetry analysis using both model-free and model fitting approaches.

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Kinetic Analysis of the Thermal Decomposition of Polymer-Bonded Explosive Based on PETN: Model-Fitting Method and Isoconversional Method

Advances in Materials Science and Engineering ◽

10.1155/2020/9260818 ◽

2020 ◽

Vol 2020 ◽

pp. 1-12

Author(s):

Trung Toan Nguyen ◽

Duc Nhan Phan ◽

Van Thom Do ◽

Hoang Nam Nguyen

Keyword(s):

Thermal Decomposition ◽

Kinetic Parameters ◽

Model Fitting ◽

Isoconversional Method ◽

Isothermal Tg ◽

Decomposition Reactions ◽

Model Free ◽

Negative Effect ◽

Adverse Influence ◽

Vacuum Stability Test

This work investigates kinetics and thermal decomposition behaviors of pentaerythritol tetranitrate (PETN) and two polymer-bonded explosive (PBX) samples created from PETN (named as PBX-PN-85 and PBX-PP-85) using the vacuum stability test (VST) and thermogravimetry (TG/DTG) techniques. Both model-free (isoconversional) and model-fitting methods were applied to determine the kinetic parameters of the thermal decomposition. It was found that kinetic parameters obtained by the modified Kissinger–Akahira–Sunose method (using non-isothermal TG/DTG data) were close to those obtained by the isoconversional and model-fitting methods that use isothermal VST data. The activation energy values of thermal decomposition reactions were 125.6–137.1, 137.3–144.9, and 143.9–152.4 kJ·mol−1 for PBX-PN-85, PETN, and PBX-PP-85, respectively. The results demonstrate the negative effect of the nitrocellulose-based binder in reducing the thermal stability of single PETN, while the polystyrene-based binder seemingly shows no adverse influence on the thermal decomposition of PETN in our presented PBX compositions.

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Thermal decomposition of potassium titanium oxalate

Journal of the Serbian Chemical Society ◽

10.2298/jsc100615083m ◽

2011 ◽

Vol 76 (7) ◽

pp. 1015-1026 ◽

Cited By ~ 2

Author(s):

Karuvanthodi Muraleedharan ◽

Labeeb Pasha

Keyword(s):

Carbon Dioxide ◽

Thermal Decomposition ◽

Carbon Monoxide ◽

Model Fitting ◽

Nitrogen Atmosphere ◽

Single Step ◽

Heating Rates ◽

Decomposition Stage ◽

Model Free ◽

Good Agreement

The thermal decomposition of potassium titanium oxalate (PTO) was studied using non-isothermal thermogravimetry at different heating rates under a nitrogen atmosphere. The thermal decomposition of PTO proceeds mainly through five stages forming potassium titanate. The theoretical and experimental mass loss data are in good agreement for all stages of the thermal decomposition of PTO. The third thermal decomposition stage of PTO, the combined elimination of carbon monoxide and carbon dioxide, were subjected to kinetic analyses both by the method of model fitting and by the model free approach, which is based on the isoconversional principle. The model free analyses showed that the combined elimination of carbon monoxide and carbon dioxide and formation of final titanate in the thermal decomposition of PTO proceeds through a single step with an activation energy value of about 315 kJ mol-1.

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The Development of Pemetrexed Diacid-Loaded Gelatin-Cloisite 30B (MMT) Nanocomposite for Improved Oral Efficacy Against Cancer: Characterization, In-Vitro and Ex-Vivo Assessment

Current Drug Delivery ◽

10.2174/1567201817666200210120231 ◽

2020 ◽

Vol 17 (3) ◽

pp. 246-256

Author(s):

Kriti Soni ◽

Ali Mujtaba ◽

Md. Habban Akhter ◽

Kanchan Kohli

Keyword(s):

Drug Release ◽

Oral Delivery ◽

Ex Vivo ◽

Confocal Laser ◽

Release Mechanism ◽

Scanning Calorimetry ◽

Sem Images ◽

Cloisite 30B ◽

Ft Ir

Aim: The intention of this investigation was to develop Pemetrexed Diacid (PTX)-loaded gelatine-cloisite 30B (MMT) nanocomposite for the potential oral delivery of PTX and the in vitro, and ex vivo assessment. Background: Gelatin/Cloisite 30 B (MMT) nanocomposites were prepared by blending gelatin with MMT in aqueous solution. Methods: PTX was incorporated into the nanocomposite preparation. The nanocomposites were investigated by Fourier Transmission Infra Red Spectroscopy (FT-IR), Differential Scanning Calorimetry (DSC), Scanning Electron Microscope (SEM) X-Ray Diffraction (XRD) and Confocal Laser Microscopy (CLSM). FT-IR of nanocomposite showed the disappearance of all major peaks which corroborated the formation of nanocomposites. The nanocomposites were found to have a particle size of 121.9 ± 1.85 nm and zeta potential -12.1 ± 0.63 mV. DSC thermogram of drug loaded nanocomposites indicated peak at 117.165 oC and 205.816 oC, which clearly revealed that the drug has been incorporated into the nanocomposite because of cross-linking of cloisite 30 B and gelatin in the presence of glutaraldehyde. Results: SEM images of gelatin show a network like structure which disappears in the nanocomposite. The kinetics of the drug release was studied in order to ascertain the type of release mechanism. The drug release from nanocomposites was in a controlled manner, followed by first-order kinetics and the drug release mechanism was found to be of Fickian type. Conclusion: Ex vivo gut permeation studies revealed 4 times enhancement in the permeation of drug present in the nanocomposite as compared to plain drug solution and were further affirmed by CLSM. Thus, gelatin/(MMT) nanocomposite could be promising for the oral delivery of PTX in cancer therapy and future prospects for the industrial pharmacy.

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Optimization of the Production Process and Product Quality of Titanate Nanotube–Drug Composites

Nanomaterials ◽

10.3390/nano9101406 ◽

2019 ◽

Vol 9 (10) ◽

pp. 1406 ◽

Cited By ~ 1

Author(s):

Yasmin Ranjous ◽

Géza Regdon ◽

Klára Pintye-Hódi ◽

Tamás Varga ◽

Imre Szenti ◽

...

Keyword(s):

Scanning Calorimetry ◽

Good Solubility ◽

Composite Formation ◽

Alternative Materials ◽

High Volatility ◽

Ft Ir ◽

Fast Disintegrating Tablets ◽

As Solubility ◽

Properties Of Composites

Recently, there has been an increasing interest in the application of nanotubular structures for drug delivery. There are several promising results with carbon nanotubes; however, in light of some toxicity issues, the search for alternative materials has come into focus. The objective of the present study was to investigate the influence of the applied solvent on the composite formation of titanate nanotubes (TNTs) with various drugs in order to improve their pharmacokinetics, such as solubility, stability, and bioavailability. Composites were formed by the dissolution of atenolol (ATN) and hydrochlorothiazide (HCT) in ethanol, methanol, 0.01 M hydrochloric acid or in ethanol, 1M sodium hydroxide, dimethylformamide (DMF), dimethyl sulfoxide (DMSO), respectively, and then they were mixed with a suspension of TNTs under sonication for 30 min and vacuum-dried for 24 h. The structural properties of composites were characterized by SEM, TEM, FT-IR, differential scanning calorimetry (DSC), thermogravimetric (TG) analysis, and optical contact angle (OCA) measurements. Drug release was determined from the fast disintegrating tablets using a dissolution tester coupled with a UV–Vis spectrometer. The results revealed that not only the good solubility of the drug in the applied solvent, but also the high volatility of the solvent, is necessary for an optimal composite-formation process.

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Torrefaction Thermogravimetric Analysis and Kinetics of Sorghum Distilled Residue for Sustainable Fuel Production

Sustainability ◽

10.3390/su13084246 ◽

2021 ◽

Vol 13 (8) ◽

pp. 4246

Author(s):

Shih-Wei Yen ◽

Wei-Hsin Chen ◽

Jo-Shu Chang ◽

Chun-Fong Eng ◽

Salman Raza Naqvi ◽

...

Keyword(s):

Kinetic Model ◽

Pso Algorithm ◽

Nitrogen Atmosphere ◽

Computational Method ◽

Weight Changes ◽

Design And Optimization ◽

Thermogravimetric Analyzer ◽

Model Free ◽

Different Temperatures ◽

Kinetics Of

This study investigated the kinetics of isothermal torrefaction of sorghum distilled residue (SDR), the main byproduct of the sorghum liquor-making process. The samples chosen were torrefied isothermally at five different temperatures under a nitrogen atmosphere in a thermogravimetric analyzer. Afterward, two different kinetic methods, the traditional model-free approach, and a two-step parallel reaction (TPR) kinetic model, were used to obtain the torrefaction kinetics of SDR. With the acquired 92–97% fit quality, which is the degree of similarity between calculated and real torrefaction curves, the traditional method approached using the Arrhenius equation showed a poor ability on kinetics prediction, whereas the TPR kinetic model optimized by the particle swarm optimization (PSO) algorithm showed that all the fit qualities are as high as 99%. The results suggest that PSO can simulate the actual torrefaction kinetics more accurately than the traditional kinetics approach. Moreover, the PSO method can be further employed for simulating the weight changes of reaction intermediates throughout the process. This computational method could be used as a powerful tool for industrial design and optimization in the biochar manufacturing process.

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Preparation, Thermal, and Thermo-Mechanical Characterization of Polymeric Blends Based on Di(meth)acrylate Monomers

Polymers ◽

10.3390/polym13060878 ◽

2021 ◽

Vol 13 (6) ◽

pp. 878

Author(s):

Krystyna Wnuczek ◽

Andrzej Puszka ◽

Łukasz Klapiszewski ◽

Beata Podkościelna

Keyword(s):

Mechanical Analysis ◽

Attenuated Total Reflection ◽

Scanning Calorimetry ◽

Force Microscopy ◽

Chemical Structures ◽

Atomic Force ◽

Polymeric Blends ◽

Ft Ir ◽

Acrylate Monomers ◽

Synthesized Materials

This study presents the preparation and the thermo-mechanical characteristics of polymeric blends based on di(meth)acrylates monomers. Bisphenol A glycerolate diacrylate (BPA.GDA) or ethylene glycol dimethacrylate (EGDMA) were used as crosslinking monomers. Methyl methacrylate (MMA) was used as an active solvent in both copolymerization approaches. Commercial polycarbonate (PC) was used as a modifying soluble additive. The preparation of blends and method of polymerization by using UV initiator (Irqacure® 651) was proposed. Two parallel sets of MMA-based materials were obtained. The first included more harmless linear hydrocarbons (EGDMA + MMA), whereas the second included the usually used aromatic copolymers (BPA.GDA + MMA). The influence of different amounts of PC on the physicochemical properties was discussed in detail. Chemical structures of the copolymers were confirmed by attenuated total reflection–Fourier transform infrared (ATR/FT-IR) spectroscopy. Thermo-mechanical properties of the synthesized materials were investigated by means of differential scanning calorimetry (DSC), thermogravimetric (TG/DTG) analyses, and dynamic mechanical analysis (DMA). The hardness of the obtained materials was also tested. In order to evaluate the surface of the materials, their images were obtained with the use of atomic force microscopy (AFM).

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