Study of CaO–WO3–P2O5 glass system by dielectric properties, IR spectra and differential thermal analysis

PbO-Ga2O3-P2O5 glasses containing different amounts of Cr2O3, ranging from 0 to 1.0 mol%, were prepared. The dielectric properties (viz., constant ε’, loss tanδ , ac conductivity σac over a wide range of frequencies and temperatures, dielectric breakdown strength) have been studied as a function of the concentration of chromium ions. An anomaly has been observed in the dielectric properties of these glasses, when the concentration of Cr2O3 is about 0.4 mol%. This anomaly has been explained in the light of different oxidation states of chromium ions with the aid of data of differential thermal analysis and optical absorption spectra of these glasses.

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A Study of nucleation and devitrification kinetics of a low-melting-point solder-glass system PbO-ZnO-B2O3 by differential thermal analysis

Thermochimica Acta ◽

10.1016/0040-6031(90)80283-5 ◽

1990 ◽

Vol 161 (1) ◽

pp. 29-36 ◽

Cited By ~ 2

Author(s):

Jinn-Shing Lee ◽

Jaw-Chay Perng ◽

Ching-Wang Huang

Keyword(s):

Thermal Analysis ◽

Differential Thermal Analysis ◽

Melting Point ◽

Glass System ◽

Kinetics Of

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Analisis Transisi Fasa dan Sifat Dielektrik Pada Li2CoSiO4 yang Dipreparasi dari Silika Sekam Padi dan Produk Daur Ulang Katoda Baterai Ion Litium Bekas

ALCHEMY Jurnal Penelitian Kimia ◽

10.20961/alchemy.15.1.24622.89-103 ◽

2019 ◽

Vol 15 (1) ◽

pp. 89

Author(s):

Agus Riyanto ◽

Simon Sembiring ◽

Megawati Megawati ◽

Ni’matil Mabarroh ◽

Junaidi Junaidi ◽

...

Keyword(s):

Phase Transition ◽

Thermal Analysis ◽

Dielectric Constant ◽

Differential Thermal Analysis ◽

Dielectric Properties ◽

Lithium Ion Batteries ◽

Rice Husk ◽

Lithium Ion ◽

Polymorphic Transition ◽

Rice Husk Silica

Studi ini mendeskripsikan analisis transisi fasa dan sifat dielektrik pada bahan litium kobalt silikat (Li2CoSiO4) yang dipreparasi dari silika sekam padi dan produk daur ulang katoda baterai ion litium bekas dengan perbandingan massa 1:1. Transisi fasa pada sampel Li2CoSiO4 dipelajari menggunakan teknik termogravimetry/differential thermal analysis (TG/DTA). Sedangkan, nilai konstanta dielektrik pada sampel yang telah disinter pada suhu 600 – 900 oC dikarakterisasi menggunakan inductance, capacitance, dan resistance (LCR) meter. Hasilnya, pada rentang suhu 410 – 850 oC terjadi transisi polimorfik fasa menjadi fasa . Suhu 850 oC juga merupakan titik transisi dimana fasa berubah menjadi fasa . Transisi fasa yang terjadi pada sampel Li2CoSiO4 diikuti dengan peningkatan nilai konstanta dielektrik dalam rentang frekuensi 450 – 100.000 Hz.Analysis of Phase Transition and Dielectric Properties of Li2CoSiO4 Prepared from Rice Husk Silica and The Recycling Product of Used Lithium Ion Batteries Cathode. This study describes the analysis of the phase transition and dielectric properties of lithium cobalt silicate (Li2CoSiO4) prepared from rice husk silica and the recycling product of used lithium ion batteries cathode with mass ratio of 1:1. Phase transition in Li2CoSiO4 sample was studied using thermogravimetry/differential thermal analysis (TG/DTA) techniques. Meanwhile, the dielectric constant value in the samples sintered at temperature of 600 – 900 oC were characterized using inductance, capacitance, and resistance (LCR) meter. As a result, a polymorphic transition from phase to phase was occured in the temperature range of 410 – 850 oC. Temperature of 850 oC is a transition point from phase to phase. The phase transitions occured in the Li2CoSiO4 was followed by the increasing of the dielectric constant in the frequency range of 450 – 100,000 Hz.

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Differential thermal analysis and infrared studies on the effect of impurities on aragonite–calcite transformation

Canadian Journal of Chemistry ◽

10.1139/v78-006 ◽

1978 ◽

Vol 56 (1) ◽

pp. 32-35 ◽

Cited By ~ 15

Author(s):

Chebrolu RamaMohan Rao ◽

Pratap Narain Mehrotra

Keyword(s):

Thermal Analysis ◽

Differential Thermal Analysis ◽

Ir Spectra ◽

Pure Form ◽

Energy Of Activation ◽

Absorption Bands ◽

Infrared Studies ◽

Effect Of Impurities

The transformation of aragonite to calcite (A–C) is an irreversible reconstructive transformation involving a change from 6 to 9 in the primary coordination. Cationic impurities like Na+, Mg2+, Zn2+, Y3+, La3+, Nd3+, Gd3+, Dy3+ have been doped in pure aragonite and their effect on the kinetics and energetics of its transformation to calcite is studied. By employing a DTA technique, the enthalpy and energy of activation for the transformation have been calculated. The ir spectra of aragonite and calcite in pure form and with various impurities have been studied and the effect of impurities on absorption bands discussed.

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Zeolites Fit For A Crown: Probing Host-Guest Interactions with Thermogravimetric Methods

10.26434/chemrxiv.7429961 ◽

2018 ◽

Author(s):

Asel Sartbaeva ◽

Paul R. Raithby ◽

Remi Castaing ◽

Antony Nearchou

Keyword(s):

Mass Spectrometry ◽

Thermal Analysis ◽

Differential Thermal Analysis ◽

Petrochemical Industry ◽

Rational Use ◽

New Methodologies ◽

First Time ◽

Kinetics Of

Through a combination of thermogravimetry, mass spectrometry and differential thermal analysis, we demonstrate for the first time that all four zeolites show experimental differences in their host-guest interactions with 18C6. In addition, we have estimated the kinetics of 18C6 decomposition, which is a technique that has not been applied to zeolites previously. Using these findings as a toolkit, a more rational use of OSDAs can be utilised to prepare designer zeolites. Furthermore, the new methodologies presented herein can be applied to current zeolites, such as MFI-type zeolites used in the petrochemical industry.

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PHASE EQUILIBRIUM IN THE AS2TE3-TM2TE3 SYSTEM.

EurasianUnionScientists ◽

10.31618/esu.2413-9335.2020.5.77.985 ◽

2020 ◽

Vol 5 (8(77)) ◽

pp. 65-68

Author(s):

Teymur Mammad Ilyasly ◽

Rahman Hasanaga Fatullazade ◽

Zakir Islam Ismailov ◽

Nigar Nadir Jafarova

Keyword(s):

Thermal Analysis ◽

Solid Solution ◽

Differential Thermal Analysis ◽

Phase Equilibrium ◽

Physicochemical Properties ◽

Thermal Effects ◽

Isothermal Annealing ◽

Intermediate Phase ◽

Physicochemical Analysis ◽

Two Phases

The synthesis of alloys of the system was carried out stepwise in rotary furnaces. The synthesis mode was selected based on the physicochemical properties of the elementary components. For homogenization, the alloys were subjected to isothermal annealing at 750 and 1275 K, depending on the Tm2Te3 concentration, for 250 h after homogenization of the alloys, they were subjected to physicochemical analysis. The results of differential thermal analysis showed that reversible thermal effects are observed in the alloys of the system. In alloys in a 1: 1 ratio, a new intermediate phase is formed with a composition corresponding to the TmAsTe3 compound. The homogeneity area is observed in the concentration range 52.5-47.5. It was found that in the concentration range 98.5-52.5 Tm2Te3 there are two phases - a mixture of β and of the solid solution, and in the concentration range of 47.51 mol% Tm2Te3 phases and α are in equilibrium. ) 66 The eutectic has coordinates of 11.5 mol Tm2Te3 at a temperature of 575 K.

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PENINGKATAN LAJU DISOLUSI ACYCLOVIR DENGAN METODE SISTEM DISPERSI PADAT MENGGUNAKAN POLOXAMER 188

SCIENTIA : Jurnal Farmasi dan Kesehatan ◽

10.36434/scientia.v5i1.61 ◽

2016 ◽

Vol 5 (1) ◽

pp. 6

Author(s):

Budi Setiawan ◽

Erizal Zaini ◽

Salman Umar

Keyword(s):

Electron Microscopy ◽

Thermal Analysis ◽

Scanning Electron Microscopy ◽

Fourier Transform ◽

Differential Thermal Analysis ◽

Fourier Transform Infrared ◽

X Ray Diffraction ◽

Poloxamer 188 ◽

X Ray ◽

Scanning Electron

Sebuah penelitian tentang sistem dispersi padat dari asiklovir dengan poloxamer 188 telah dilakukan formulasi dengan pencampuran secara fisika dengan rasio 1 : 1, 1 : 3, 1 : 5 dan dispersi padat 1 : 1, 1 : 3, 1 : 5 dan penggilingan 1:1 sebagai pembanding. Dispersi padat dibuat menggunakan metode pencairan (fusi), yang digabung dengan poloxamer 188 pada hotplate kemudian asiklovir dimasukkan ke dalam hasil poloxamer 188 lalu di kocok hingga membentuk masa homogen. Semua formula yang terbentuk termasuk asiklovir poloxamer 188 murni dianalisis karakterisasinya dengan Differential Thermal Analysis (DTA), X-ray Diffraction, Scanning Electron Microscopy (SEM), dan Fourier Transform Infrared (FTIR), kemudian pengambilan dilakukan (penentuan kadar) mengunakan spektrofotometer UV pada panjang gelombang 257,08 nm dan uji laju disolusi dengan aquadest bebas CO2 menggunakan metode dayung. Hasil pengambilan (penentuan kadar) menunjukkan bahwa semua formula memenuhi persyaratan farmakope Amerika edisi 30 dan farmakope Indonesia edisi 4 yaitu 95-110%. Sedangkan hasil uji laju disolusi untuk campuran fisik 1: 1, dan dispersi padat 1: 1, dan penggilingan 1: 1 menunjukkan peningkatan yang nyata dibandingkan asiklovir murni. Hal ini juga dapat dilihat dari hasil perhitungan statistik menggunakan analisis varian satu arah SPSS 17.

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Kinetics of temperature-programmed reactivation of a hydrodesulphurization catalyst

Collection of Czechoslovak Chemical Communications ◽

10.1135/cccc19833340 ◽

1983 ◽

Vol 48 (12) ◽

pp. 3340-3355 ◽

Cited By ~ 2

Author(s):

Pavel Fott ◽

Pavel Šebesta

Keyword(s):

Carbon Dioxide ◽

Thermal Analysis ◽

Differential Thermal Analysis ◽

Thin Layer ◽

Kinetic Parameters ◽

Diffusion Region ◽

Reaction Heat ◽

Gaseous Products ◽

Temperature Programmed ◽

Kinetics Of

The kinetic parameters of reactivation of a carbonized hydrodesulphurization (HDS) catalyst by air were evaluated from combined thermogravimetric (TG) and differential thermal analysis (DTA) data. In addition, the gaseous products leaving a temperature-programmed reactor with a thin layer of catalyst were analyzed chromatographically. Two exothermic processes were found to take part in the reactivation, and their kinetics were described by 1st order equations. In the first process (180-400 °C), sulphur in Co and Mo sulphides is oxidized to sulphur dioxide; in the second process (300-540 °C), in which the essential portion of heat is produced, the deposited carbon is oxidized to give predominantly carbon dioxide. If the reaction heat is not removed efficiently enough, ignition of the catalyst takes place, which is associated with a transition to the diffusion region. The application of the obtained kinetic parameters to modelling a temperature-programmed reactivation is illustrated on the case of a single particle.

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