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Abstract  

CRTA technology offers better resolution and a more detailed interpretation of the decomposition processes of a clay mineral such as sepiolite via approaching equilibrium conditions of decomposition through the elimination of the slow transfer of heat to the sample as a controlling parameter on the process of decomposition. Constant-rate decomposition processes of non-isothermal nature reveal changes in the sepiolite as the sepiolite is converted to an anhydride. In the dynamic experiment two dehydration steps are observed over the ~20–170 and 170–350 °C temperature range. In the dynamic experiment three dehydroxylation steps are observed over the temperature ranges 201–337, 337–638 and 638–982 °C. The CRTA technology enables the separation of the thermal decomposition steps.

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Abstract  

Controlled rate thermal analysis (CRTA) technology offers better resolution and a more detailed interpretation of the decomposition processes of a clay mineral such as sepiolite via approaching equilibrium conditions of decomposition through the elimination of the slow transfer of heat to the sample as a controlling parameter on the process of decomposition. Constant-rate decomposition processes of non-isothermal nature reveal changes in the sepiolite as the sepiolite is converted to an anhydride. In the dynamic experiment two dehydration steps are observed over the ~20–170 and 170–350 °C temperature range. In the dynamic experiment three dehydroxylation steps are observed over the temperature ranges 201–337, 337–638 and 638–982 °C. The CRTA technology enables the separation of the thermal decomposition steps.

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Orvosi Hetilap
Authors: Zsuzsanna Erzsébet Papp, Izabella Kelemen, and Adrienne Horváth

Absztrakt:

Bevezetés: A gyermekkori malignus betegségek igen kis részét alkotják az összes gyermekgyógyászati patológiának. A kezdeti tünetek nem specifikusak, levertség, sápadtság, tumormassza-kompresszió, csontvelő-elégtelenség jelei mutatkozhatnak. Célkitűzés: Dolgozatunk célja röviden és áttekinthetően összefoglalni a gyermekkori malignus patológiák kezdeti tünettanát, hogy gyanú esetén útmutatót nyújthassunk a „frontvonalban” dolgozó orvosoknak. Módszer: Retrospektív munkánk során a Marosvásárhelyi 2. Sz. Gyermekgyógyászati Klinika Hematoonkológia Osztályának ötéves beteganyagát néztük át, a felvételre kerülő onkológiai esetek kezdeti tünettanát tanulmányozva. Eredmények: A vizsgált periódusban 34 gyermeket diagnosztizáltunk malignus betegséggel. A jelzésértékű tünetek, amelyeket találtunk: láz, gyenge általános állapot, fogyás, csont-/hasi fájdalom, anaemia vagy thrombocytopenia tünettana, gyakori fertőzések, adenopathiák. Következtetés: A gyermekkori akut leukaemiák tünettanába tartoznak az adenopathiák, hosszan tartó lázas állapotok, csontfájdalmak és az anaemia jelei. A szolid tumorok esetében az általános állapot romlása és a fájdalmas, kompressziós tünetek dominálnak. A beteggel találkozó első orvos felelőssége óriási a jelzésértékű tünetek korai felismerése szempontjából. Orv Hetil. 2017; 158(21): 829–834.

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Abstract

Four paleosol layers indicating wet and moderate periods and five loess layers indicating dry and cold climate were separated by different methods. The following climate cycle model, based on the development of the sediment sequence created by the influence of climatic, geologic and geomorphologic phenomena, was established by detailed paleomagnetic studies (e.g. anisotropy of magnetic susceptibility (AMS), isothermal remanent magnetization (IRM), frequency dependence of magnetic susceptibility (κFD), etc.):

  1. A well-foliated magnetic fabric predominantly built up by multi-domain ferromagnetic minerals (magnetite, maghemite) was developed during the semi-arid (350–400 mm/y) and cold loessification period of the Pleistocene. The magnetic fabric can reflect the direction of dust deposition and/or the paleoslope.
  2. The accumulation period of dust was followed by the more humid (650 mm/y) pedogenic period indicated by the enrichment of superparamagnetic minerals and by the disturbed or inverse magnetic fabric developed during pedogenesis by different processes (e.g. leaching and/or bioturbation).
  3. The third period following the pedogenic period is the humid erosional phase indicated by the finely layered reworked loess. The magnetic fabric built up by multi-domain ferro- and superparamagnetic minerals is characterized by better-aligned directions of principal susceptibilities than in the wind blown material. Sheet wash and other waterlogged surface processes appeared in the fabric of these layers. This process is possibly connected to sudden, rare yet significant events with high precipitation and absence of vegetation.
  4. The cycle was closed by the beginning of the next dust accumulation period.
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Abstract

Three halotrichites namely halotrichite Fe2&SO4·Al2(SO4)3·22H2O, apjohnite Mn2&SO4·Al2(SO4)3·22H2O and dietrichite ZnSO4·Al2(SO4)3·22H2O, were analysed by both dynamic, controlled rate thermogravimetric and differential thermogravimetric analysis. Because of the time limitation in the controlled rate experiment of 900 min, two experiments were undertaken (a) from ambient to 430 °C and (b) from 430 to 980 °C. For halotrichite in the dynamic experiment mass losses due to dehydration were observed at 80, 102, 319 and 343 °C. Three higher temperature mass losses occurred at 621, 750 and 805 °C. In the controlled rate thermal analysis experiment two isothermal dehydration steps are observed at 82 and 97 °C followed by a non-isothermal dehydration step at 328 °C. For apjohnite in the dynamic experiment mass losses due to dehydration were observed at 99, 116, 256, 271 and 304 °C. Two higher temperature mass losses occurred at 781 and 922 °C. In the controlled rate thermal analysis experiment three isothermal dehydration steps are observed at 57, 77 and 183 °C followed by a non-isothermal dehydration step at 294 °C. For dietrichite in the dynamic experiment mass losses due to dehydration were observed at 115, 173, 251, 276 and 342 °C. One higher temperature mass loss occurred at 746 °C. In the controlled rate thermal analysis experiment two isothermal dehydration steps are observed at 78 and 102 °C followed by three non-isothermal dehydration steps at 228, 243 and 323 °C. In the CRTA experiment a long isothermal step at 636 °C attributed to de-sulphation is observed.

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A differenciált pajzsmirigy-karcinómás betegek gondozásában a szérumtireoglobulin alapvető tumormarker. A tireoglobulin teljes hiányát nem lehet bizonyítani immunanalitikai módszerekkel, ha a beteg szérumában tireoglobulin ellen képződő autoantitest van jelen, ami differenciált pajzsmirigy-karcinómában szenvedő betegek közel 20%-ában előfordul. Ezért a szakmai ajánlások csak a tireoglobulin-autoantitest mennyiségének ismeretében javasolják a szérumtireoglobulin-lelet értékelését. A tireoglobulin-autoantitest normális szintje nem zárja ki a zavaró hatást, ugyanis nem ismert, hogy mekkora antitest-koncentrációnál nem kell antitest-interakcióval számolnunk. Ebben a tekintetben nem következetesek az irodalmi ajánlások, mivel ritkán tesznek különbséget a tireoglobulinautoantitest-negativitás és az alacsony, de még mérhető antitestszint között. Ezért nem egyértelmű, hogy az alacsony antitestszintek mennyire befolyásolják a tireoglobulin kimutathatóságát. A szerzők az irodalmi adatok és szakmai ajánlások tükrében tekintik át a szérumtireoglobulin- és tireoglobulinautoantitest-vizsgálat preanalitikai és analitikai korlátait, és saját eredményeik alapján javaslatot tesznek a tireoglobulinmeghatározás diagnosztikai pontosságának növelésére. Orv. Hetil., 2011, 152, 743–752.

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Abstract  

Dynamic and controlled rate thermal analysis (CRTA) has been used to characterise alunites of formula [M(Al)3(SO4)2(OH)6] where M+ is the cations K+, Na+ or NH4 +. Thermal decomposition occurs in a series of steps: (a) dehydration, (b) well-defined dehydroxylation and (c) desulphation. CRTA offers a better resolution and a more detailed interpretation of water formation processes via approaching equilibrium conditions of decomposition through the elimination of the slow transfer of heat to the sample as a controlling parameter on the process of decomposition. Constant-rate decomposition processes of water formation reveal the subtle nature of dehydration and dehydroxylation.

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Journal of Thermal Analysis and Calorimetry
Authors: Sara Palmer, J. Kristóf, Veronika Vágvölgyi, Erzsébet Horváth, and R. Frost

Abstract  

The mechanism for the decomposition of hydrotalcite remains unsolved. Controlled rate thermal analysis enables this decomposition pathway to be explored. The thermal decomposition of hydrotalcites with hexacyanoferrate(II) and hexacyanoferrate(III) in the interlayer has been studied using controlled rate thermal analysis technology. X-ray diffraction shows the hydrotalcites have a d(003) spacing of 10.9 and 11.1 Å which compares with a d-spacing of 7.9 and 7.98 Å for the hydrotalcite with carbonate or sulphate in the interlayer. Calculations show dehydration with a total loss of 7 moles of water proving the formula of hexacyanoferrate(II) intercalated hydrotalcite is Mg6Al2(OH)16[Fe(CN)6]0.5·7H2O and 9.0 moles for the hexacyanoferrate(III) intercalated hydrotalcite with the formula of Mg6Al2(OH)16[Fe(CN)6]0.66·9H2O. CRTA technology indicates the partial collapse of the dehydrated mineral. Dehydroxylation combined with CN unit loss occurs in two isothermal stages at 377 and 390°C for the hexacyanoferrate(III) and in a single isothermal process at 374°C for the hexacyanoferrate(III) hydrotalcite.

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Abstract  

Dynamic and controlled rate thermal analysis has been used to characterise synthesised jarosites of formula [M(Fe)3(SO4)2(OH)6] where M is Pb, Ag or Pb–Ag mixtures. Thermal decomposition occurs in a series of steps. (a) dehydration, (b) well defined dehydroxylation and (c) desulphation. CRTA offers a better resolution and a more detailed interpretation of water formation processes via approaching equilibrium conditions of decomposition through the elimination of the slow transfer of heat to the sample as a controlling parameter on the process of decomposition. Constant-rate decomposition processes of water formation reveal the subtle nature of dehydration and dehydroxylation. CRTA offers a better resolution and a more detailed interpretation of the decomposition processes via approaching equilibrium conditions of decomposition through the elimination of the slow transfer of heat to the sample as a controlling parameter on the process of decomposition. Constant-rate decomposition processes of non-isothermal nature reveal separation of the dehydroxylation steps, since in these cases a higher energy (higher temperature) is needed to drive out gaseous decomposition products through a decreasing space at a constant, pre-set rate.

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Bioautography can be extended to a complex system called BioArena by linking different steps to it, for example dissolving a variety of compounds in the cell suspension to affect biological activity, measuring putative mediators of antibiosis, for example formaldehyde (HCHO) and hydrogen peroxide (H 2 O 2 ) in the inoculated layer, and performing densitometric and ex and in situ spectroscopic examination to follow the changes in the inhibition zones and active compounds (e.g. antibiotics and toxins). Possibilities of the basic elements of BioArena system are illustrated in this paper by results with aflatoxin B1 (AFB1). Target bacterial cells in the logarithmic growth phase were found to be the most sensitive for direct bioautography. Densitometric signals of bioautograms (negative densitometry) of 0.125–1 μg AFB1 spots showed logarithmic correlation with the amount of AFB1. The HCHO capturer L-arginine decreased whereas the HCHO generator-mobilizer Cu(II) ions increased the antibacterial-toxic effect of AFB1. The latter effect was also confirmed by negative densitometry. Besides higher levels of HCHO, a decrease of H 2 O 2 in the toxin spot was found. HCHO could also originate, among other sources, from demethylation of AFB1, which is apparent from the Fourier transform Raman spectra obtained in situ from the AFB1-containing spots. These results support the suggested role of HCHO and its reaction products with H 2 O 2 (e.g. singlet oxygen ( 1 O 2 ), ozone (O 3 )) in the antibacterial-toxic effect of AFB1.

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