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, requirement for a small sample size and ability to provide detailed information about the physical and energetic properties of a sample [ 14 ]. Another thermal analysis technique for the investigation of polymorphism is hot-stage microscopy (HSM). The

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Háttér és célok: 2016-ban a Sportmotivációs Skála javított verziója (SMS2) kapcsán végzett fordítási és validációs próbálkozásaink során megállapítottuk, hogy a magyar nyelv sajátosságai, valamint a magyar sportolók gondolkodásának eltérő vonásai nem feltétlenül teszik lehetővé a sportmotivációs skálák egy az egyben történő fordítását. Ezért az eredeti irányvonalat és az eredeti elméleti keretrendszert, vagyis az önmeghatározás- elméletet (SDT – Self-determination theory) és annak faktorait (belső motiváció, integrált, identifikált, introjektált, külső szabályozás, amotiváció) megtartva, a magyar viszonyokhoz igazított, a nemzetközi eredményekkel mégis alapvetően összevethető instrumentum megalkotását tűztük ki célul.

Módszer: Az eredeti, angol nyelvű SMS2 skála kialakításához használt 61 item fordítását követően annak 500 fős sportolói mintán történő validálására került sor feltáró és magyarázó faktoranalízis révén. A mintát 319 férfiés 181 nő alkotta, átlagos életkoruk 21,16 év (szórás 6,45) volt.

Eredmények: A feltáró faktorelemzéssel kapott magyar nyelvű Sportmotivációs Skála (H-SMS) 22 tételének faktorstruktúrája az eredeti (SMS2) mérőeszköz faktorszerkezetéhez nagyon hasonló maradt. A H-SMS végső, megerősítő faktorelemzéssel kialakított verziója 6 faktort és 19 tételt foglal magába, melyeket egy 7 fokú skálán válaszol meg a kitöltő. A végleges változat két különböző modell közül került kiválasztásra, és maximálisan megfelel a pszichometriai instrumentumokkal szemben támasztott érvényességi (CMIN/df = 1,77; SRMSR = 0,042; RMSEA = 0,040; PCLOSE = 0,983; NFI = 0,953; TLI = 0,973; CFI = 0,979), valamint megbízhatósági (Cronbach alfa = 0,79–0,89; CR = 0,80–0,94; AVE = 0,65–0,89; AVE > MSV) kritériumoknak. Az eredetitől eltérően a végső struktúrában az intrinzik motivációt mérő faktort két alfaktorra osztottuk: az észlelt kompetenciára (kognitív) és az önhatékonyság növelésére (effektív) irányuló intrinzik motivációra.

Konklúzió: Az eredmények alapján biztonsággal kijelenthető, hogy a skála messzemenőkig alkalmas a sporthoz köthető motivációk mérésére, valamint a nemzetközi eredményekkel való összehasonlításra is.

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Journal of Thermal Analysis and Calorimetry
Authors: J. M. Ginés, M. J. Arias, J. R. Moyano, Cs. Novak, G. Pokol, and P. J. Sánchez-Soto

A thermal study using DSC and Hot Stage Microscopy (HSM) was carried out to investigate the interaction in solid state of the binary system PEG 4000 — oxazepam, and to establish their phase diagram. The eutectic composition, which melting occurs at lower temperature as compared with the pure components, has been determined. The results obtained by DSC and HSM have indicated that PEG 4000 — oxazepam mixtures displays no obvious incompatibilities, and that the system shows a typical eutectic behaviour. However because of the closeness of the melting of PEG 4000 to the eutectic temperature, it was difficult to determine precisely the eutectic composition and temperature on the basis of DSC measurements alone. The use of heats of fusion corresponding to physical mixtures allowed an estimation of the eutectic composition at 6% w/w oxazepam. Additional information of temperature (57.6‡C) and composition (5–10% w/w oxazepam) of the eutectic was obtained by HSM using the contact method. This low melting temperature in this range of compositions offers advantages in terms of drug stability and easy manufacture.

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Abstract  

Two polymorphs of the bronchodilator tulobuterol (2-chloro-α-[[(1,1-dimethylethyl)- amino]-methyl]benzenemethanol) with melting points differing by ~10 K were isolated and characterized by thermal analysis (HSM, TG, DSC), as well as powder and single crystal X-ray diffraction. Analysis of melting data for Forms 1 and 2 revealed a monotropic relationship, with ΔG 0, the Gibbs free energy difference at the melting temperature of the lower melting form, less than 1 kJ mol-1. This small difference is reconciled with known structural features in the crystals of the two forms. The hydrogen bonding capacity of the tulobuterol molecule is fully utilised in both polymorphs in forming a common trimeric unit via three strong O-H···N interactions. Consequently only weak intermolecular forces characterize the packing of the trimers in the monoclinic polymorph (Form 1, P21/n, Z =12) and the triclinic polymorph (Form 2, P(-1),Z =6).

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Abstract  

Thermochemical properties of crown ether complexes have been studied by simultaneous TG-DTA (thermogravimetric analysis-differential thermal analysis) coupled with a mass spectrometer, DSC (differential scanning calorimetry) and hot stage microscopy (HSM). The examined complexes contain benzylammonium- [BA], (R)-(+)-a-phenylethylammonium- [(R)-PEA], (R)-(+)- and (S)-(-)-a-(1-naphthyl)ethylammonium perchlorate [(R)-NEA and (S)-NEA] salts as guests. In the cases of BA and (R)-PEA an achiral pyridono-18-crown-6 ligand [P18C6], and in the case of (R)-NEA and (S)-NEA a chiral (R,R)-dimethylphenazino-18-crown-6 ligand [(R,R)-DMPh18C6] was used as host molecule to obtain four different crown ether complexes. In all cases, the melting points of the complexes were higher than those of both the host and the guest compounds. The decomposition of the complexes begins immediately after their melting is completed, while the BA and (R)-PEA salts and the crown ether ligands are thermally stable by 50 to 100 K above their melting points. During the decomposition of the salts and the four complexes strongly exothermic processes can be observed which are due to oxidative reactions of the perchlorate anion. Ammonium perchlorate crystals were identified among the decomposition residues of the salts. P18C6 was observed to crystallize with two molecules of water. The studied complexes of P18C6 did not contain any solvate. BA was observed to exhibit a reversible solid-solid phase transition upon heating. The heterochiral complex consisting of (S)-NEA and (R,R)-DMPh18C6 shows a solid-solid phase transition followed by two melting points. HSM observations identified three crystal modifications, two of them simultaneously co-existing.

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Journal of Thermal Analysis and Calorimetry
Authors: F. Giordano, A. Rossi, R. Bettini, A. Savioli, A. Gazzaniga, and Cs. Novák

Abstract  

The thermal behavior of binary mixtures of paracetamol and a polymeric excipient (microcrystalline cellulose, hydroxypropylmethylcellulose and cross-linked poly(vinylpyrrolidone)) was investigated. The physical mixtures, ranging from 50 to 90% by mass of drug, were submitted to a heating-cooling-heating program in the 35–180C temperature range. Solid-state analysis was performed by means of differential scanning calorimetry (DSC), hot stage microscopy (HSM), micro-Fourier transformed infrared spectroscopy (MFTIR), and scanning electron microscopy (SEM). The polymeric excipients were found to address in a reproducible manner the recrystallization of molten paracetamol within the binary mixture into Form II or Form III. The degree of crystallinity of paracetamol in the binary mixtures, evaluated from fusion enthalpies during the first and second heating scans, was influenced by the composition of the mixture, the nature of the excipient and the thermal history. In particular, DSC on mixtures with cross-linked poly(vinylpyrrolidone) and hydroxypropylmethylcellulose with drug contents below 65 and75%, respectively, evidenced the presence only of amorphous paracetamol after the cooling phase. Microcrystalline cellulose was very effective in directing the recrystallization of molten paracetamol as Form II.

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Abstract  

Much has been written about the discovery by physicists of quasicrystals and the almost simultaneous discovery by geometers of nonperiodic tessellations and honeycombs. A somewhat similar serendipity occurred when crystallographers saw what happens when identical balls of plastic clay or lead shot are shaken together and uniformly compressed, or when the bubbles (all of the same size) in a froth are measured; and almost simultaneously geometers investigated statistical honeycombs. Alternate doses of oil and water in a thin tube may be regarded as a one-dimensional "froth" {∞}, each "bubble" having just 2 neighbours. Analogously, soapsuds sandwiched between parallel glass plates (close together) may be regarded as a two-dimensional froth {6,3}, each bubble having just 6 neighbours. Three-dimensional froth presents a far more difficult problem because there is no regular honeycomb having 4 cells at each vertex. The best available substitute seems to be a "statistical" honeycomb {p, 3,3} where p, instead of being rational, is a real number such as π/ arctan
\documentclass{aastex} \usepackage{amsbsy} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{bm} \usepackage{mathrsfs} \usepackage{pifont} \usepackage{stmaryrd} \usepackage{textcomp} \usepackage{upgreek} \usepackage{portland,xspace} \usepackage{amsmath,amsxtra} \pagestyle{empty} \DeclareMathSizes{10}{9}{7}{6} \begin{document} $$\sqrt {\frac{1}{2}}$$ \end{document}
, somewhere between 5 and 6. ({5,3,3} is the regular 120-cell and {6,3,3} is non-Euclidean.) In such a statistical honeycomb, the number of neighbours for each bubble is 13.4, in good agreement with experiments in which the actual number is 12 or 14 and sometimes 15, but most often 13. Hoping not to be too fanciful, we venture to look for a statistical honeycomb {q,3,3,3} in Euclidean 4-space, q being a real number such as π/ arctan
\documentclass{aastex} \usepackage{amsbsy} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{bm} \usepackage{mathrsfs} \usepackage{pifont} \usepackage{stmaryrd} \usepackage{textcomp} \usepackage{upgreek} \usepackage{portland,xspace} \usepackage{amsmath,amsxtra} \pagestyle{empty} \DeclareMathSizes{10}{9}{7}{6} \begin{document} $$\sqrt {\frac{3}{5}}$$ \end{document}
, somewhere between 4 and 5. ({4,3,3,3} is the 5-cube while {5,3,3,3} is non-Euclidean.) In this case the number of neighbours for one bubble in the 4-dimensional froth is computed to be about 28.
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Abstract  

Isostructural solvates of the 1:1 molecular complex between the antibacterial drugs tetroxoprim (TXP) and sulfametrole (SMTR) with formulae TXPSMTRCH3OH (I), TXPSMTRC2H5OH (II) and TXPSMTRH2O (III), were investigated to establish their propensity for guest exchange. Separate exposure of powdered (I), (II) and (III) to a saturated atmosphere of each solvent of the complementary solvate pair at ambient temperature resulted in reversible solvent exchange in all cases. DSC and TG were the methods of choice for monitoring the exchange processes since (I)-(III) have distinct onset temperatures of desolvation and characteristic mass losses. Interpretation of the results in terms of the known locations of the solvent molecules in crystals of (I)-(III) led to the conclusion that solvent exchange probably proceeds by a co-operative mechanism involving material transport through channels while the common host framework is maintained.

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Abstract  

Thermal analysis (DSC and HSM), and equilibrium solubility determinations were carried out to elucidate the mechanism of interaction at the solid state in the binary system triamterene-D-mannitol. Physical mixtures (5–90% w/w triamterene) and solid dispersions (5 up to 40% w/w triamterene) were prepared and studied. From DSC and HSM results, the thermal changes were associated with the variations in composition of the binary mixture, being more pronounced in the range 20–50% w/w. The binary phase diagram was proposed, although the exact position of the eutectic was uncertain. This is in accordance with a partial dissolution process detected by HSM. A linear increase in the solubility of triamterene with increasing aqueous mannitol concentration was obtained. The thermodynamic parameters of the solution properties were calculated, with an activation energy value of 96.081 kJ/mole. The solubilization increase was associated with complexation processes and hydrogen bonding formation.

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Summary

Four preparatory drawings for stained glass windows by Sigmund, one of the members of the Munich Hebenstreit family are kept in the Budapest Museum of Fine Arts and in the British Museum (signed HSM and dated 1603). They represent scenes from the Apocalypse, based on woodcuts by Sebald Beham. Behams woodcuts follow the illustrations by the Monogrammist AW in the revised edition of 1530 by Martin Luthers New Testament translation.

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