ChemInform Abstract: THERMISCHE UMWANDLUNGEN VON THALLIUMTRIPHOSPHATHYDRAT

Prodan, E. A.; Pavlyuchenko, M. M.; Prodan, L. I.; Sotnikova‐Yuzhik, V. A.; Sotnikob‐Yuzhik, Yu. M.; Peslyak, G. V.

doi:10.1002/chin.197245055

Cited by 4 publications

(5 citation statements)

References 0 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…IR spectroscopy was performed with a UR-20 spectrometer (KBr disk method). The X-ray diffraction characteristics of Li4P2OT(/) corresponded to the published data for Li4P207(/) [2], and the characteristics of LisPaOxo" 5H20 also corresponded to the previously obtained data [12].…”

Section: Methodsmentioning

confidence: 55%

Thermal transformations of lithium phosphates

Galogaza

Prodan

Sotnikova‐Yuzhik

et al. 1986

Journal of Thermal Analysis

Self Cite

View full text Add to dashboard Cite

The iso-and non-isothermal transformations taking place on the heating of LiH2PO,~, Li2HPO4, LisPaOio-5H20, mixtures of LiH~PO4 + 2LizHPO 4 and LiH2PO4 + Li4P2OT(/) in vacuum, air and water vapour atmospheres at 20-1050" were studied using TG, DTG, DSC, DTA, IR spectroscopy, XRD and TLC analyses. It was shown that solid-phase interaction of the mixture components with the general ratio Li: P ~ 5: 3, in contrast to the interaction of analogous sodium (potassium) phosphate mixture components, does not lead to the quantitative formation of anhydrous triphosphate. This is explained by the high crystallization rate of lithium pyrophosphate, which, due to its low reactivity, does not participate in further anion condensation. The increase of triphosphate yield is promoted by the liquid pha~e formed on disproportionation of acid salts, on melting of reaction components or as a result of introduction of urea additive.

show abstract

Section: Methodsmentioning

confidence: 55%

Thermal transformations of lithium phosphates

Galogaza

Prodan

Sotnikova‐Yuzhik

et al. 1986

Journal of Thermal Analysis

Self Cite

View full text Add to dashboard Cite

show abstract

“…GC (23), UV and IR spectrophotometry (17,18,22,24,25), colorimetry (11-13, 19, 20, 26, 27), and polarography ( I 1, 28,29). Although some of these methods may be superior to the USP lime method, no assay procedure reported to date is specific for morphine.…”

Section: Discussionmentioning

confidence: 99%

“…A great majority of these have concerned inorganic salt decompositions [carbonates (1)(2)(3)(4)(5)(6)(7)(8)(9), oxalates (1&17), and permanganates (18)(19)(20)(21)], and several general patterns have been proposed as primary mechanisms in the decompositions; most notable of these are the Prout-Tompkins model (21) and the power laws (22)(23)(24)(25). Some studies have been reported in the pharmaceutical literature, notably the ones by Leeson and Mattocks (26), by Kornblum and Sciarrone (27), by Garrett et al (28), and by Guillory and Higuchi (29).…”

mentioning

confidence: 99%

Decomposition of Benzoic Acid Derivatives in Solid State

Carstensen

Musa

1972

Journal of Pharmaceutical Sciences

View full text Add to dashboard Cite

“…Let us list some of them. The kinetic characteristics of the process, not impeded by the reverse reaction, must be obtained under the conditions of "limit vacuum" [7] (or in inert gas flow). The particle size range of the sample should be dmax/drnin < 6 [9] (however, a too fine fraction may lead to a diffuse course of the process [7]), no temperature gradient should be present in the sample (the dimensionless criteria are as follows: temperature increase rate f2 <0.01 Bi < 1 [10]).…”

Section: E~ >E2 >E~mentioning

confidence: 99%

A comparative study of the thermal stability of coordination compounds by thermoanalytical methods

Логвиненко

Gegola

Myachina

1978

Journal of Thermal Analysis

View full text Add to dashboard Cite

The informative capacity of thermal analysis in the evaluation of the thermal stability of coordination compounds involving the evolution of volatile ligands is discussed. The temperature of decomposition under quasi-equilibrium conditions (Q-derivatograph, quasi-isobaric, quasi-isothermal operation) is suitable for characterizing the thermodynamic stability of compounds. The initial temperature of decompbsition at linear heating indicates the reaching of a defined value of the rate constant (depending on the sensitivity of the sensing device of the instrument and on expel'imental conditions). The temperature sequence of increasing thermal stability may not coincide with the sequence of increasing activation energy values, since in the majority of cases it demands on the value of activation enthropy.Many thermal reactions of coordination compounds involving the evolution of volatile ligands may be regarded as heterogeneous ligand exchange processes. It is therefore of interest to compare thermodynamic and kinetic stabilities for series of coordination compounds in similar-type. The sequences may be obtained if the equilibrium constants and the rate constants of the reactions in question are known at some standard temperature. It is difficult, however, to choose the standard temperature. Known sequences of stability for reactions of coordination compounds in solution are based, for instance, on data of stability constants determined at 25 ~ , and the total temperature range of the experiment does not exceed 0 to 100 ~ (at atmospheric pressure). The majority of crystalline coordination compounds are being synthetized at ambient temperature, and are rather stable at 25 ~ both kinetically and thermodynamically. The temperature range of interest for studying solid-phase transformations is much broader.Since thermal analysis is a traditional method for studying coordination compounds efforts have been made for a long time past to obtain qualitative sequences of their thermal stability indirectly from thermoanalytical data without determining the numerical values of the equilibrium constants and rate constants (at standard temperature).The sequences of the thermodynamic stability of isostructural compounds in similar-type can be obtained using the Q-derivatograph [1-2]. The particular features of the experimental method are as follows: dynamic heating of the sample at a determined rate takes place only up to the start of weight loss. As soon as weight loss begins a special system takes over the control of oven heating, the 5

show abstract

ChemInform Abstract: THERMISCHE UMWANDLUNGEN VON THALLIUMTRIPHOSPHATHYDRAT

Cited by 4 publications

References 0 publications

Thermal transformations of lithium phosphates

Thermal transformations of lithium phosphates

Decomposition of Benzoic Acid Derivatives in Solid State

A comparative study of the thermal stability of coordination compounds by thermoanalytical methods

Contact Info

Product

Resources

About