Thermal decomposition of foundry resins: A determination of organic products by thermogravimetry–gas chromatography–mass spectrometry (TG–GC–MS)

AbstractThe article presents the results of research on thermal decomposition of Ester-Cured Alkaline Phenolic No-Bake (ALPHASET) binders used in molding technology. In the ALPHASET system phenol-formaldehyde resin of resole type is cured with a liquid mixture of esters. Under the influence of the molten metal the thermal decomposition of the binder follows, resulting in the evolution of gases, often harmful, e.g. from benzene, toluene, ethylbenzene and xylenes (BTEX) or Polycyclic Aromatic Hydrocarbon (PAH) groups. The identification of gases evolved during the pyrolysis of the binders was carried out and their decomposition temperatures were determined using the Thermogravimetry–Gas Chromatography–Mass Spectrometry (TG–GC–MS) technique. The tests were subjected to two types of binders from different manufacturers. Among the products of pyrolysis there have been identified mainly benzene and its derivatives, and phenol and its derivatives. Compounds identified in pyrolytic gas are largely considered to be harmful to humans and the environment (some of the compounds are carcinogenic and mutagenic). The presented results of the TG–GC–MS measurements show that the applied analytic methods are feasible to perform a qualitative and also quantitative characterization of the binder samples

Thermal decomposition of foundry resins: A determination of organic products by thermogravimetry–gas chromatography–mass spectrometry (TG–GC–MS)

AbstractThe article presents the results of research on thermal decomposition of Ester-Cured Alkaline Phenolic No-Bake (ALPHASET) binders used in molding technology. In the ALPHASET system phenol-formaldehyde resin of resole type is cured with a liquid mixture of esters. Under the influence of the molten metal the thermal decomposition of the binder follows, resulting in the evolution of gases, often harmful, e.g. from benzene, toluene, ethylbenzene and xylenes (BTEX) or Polycyclic Aromatic Hydrocarbon (PAH) groups. The identification of gases evolved during the pyrolysis of the binders was carried out and their decomposition temperatures were determined using the Thermogravimetry–Gas Chromatography–Mass Spectrometry (TG–GC–MS) technique. The tests were subjected to two types of binders from different manufacturers. Among the products of pyrolysis there have been identified mainly benzene and its derivatives, and phenol and its derivatives. Compounds identified in pyrolytic gas are largely considered to be harmful to humans and the environment (some of the compounds are carcinogenic and mutagenic). The presented results of the TG–GC–MS measurements show that the applied analytic methods are feasible to perform a qualitative and also quantitative characterization of the binder samples

The revitalisation project as a tool to revival and regenerate the object's value illustrated with an example of Oberau castle

Rewitalizacja to przywrócenie wartości utraconych zespołów, wsi, miast. Zaprezentowany przykład koncepcji projektowej ukazuje sposoby wykorzystania walorów miejsca z równoczesną próbą ich aktywizacji dla turystyki regionu. Prace prowadzone na wielu płaszczyznach, przy poparciu społecznym, prowadzić mogą do odzyskania atrakcyjnego lokalnego dziedzictwa, przynosząc realne zyski gospodarcze i kulturowe.Revitalisation is to regenerate the lost objects’, villages’ and cities’ value. The presented example of a design concept presents how to take advantage of the place’s value with the simultaneous attempt to revival tourist offer of the region. Analyses carried out in numerous dimensions, with the support of society, can lead to the recovery of attractive local heritage, bringing real economic and cultural benefits

Thermal decomposition of foundry resins: A determination of organic products by thermogravimetry–gas chromatography–mass spectrometry (TG–GC–MS)

The article presents the results of research on thermal decomposition of Ester-Cured Alkaline Phenolic No-Bake (ALPHASET) binders used in molding technology. In the ALPHASET system phenol-formaldehyde resin of resole type is cured with a liquid mixture of esters. Under the influence of the molten metal the thermal decomposition of the binder follows, resulting in the evolution of gases, often harmful, e.g. from benzene, toluene, ethylbenzene and xylenes (BTEX) or Polycyclic Aromatic Hydrocarbon (PAH) groups. The identification of gases evolved during the pyrolysis of the binders was carried out and their decomposition temperatures were determined using the Thermogravimetry–Gas Chromatography–Mass Spectrometry (TG–GC–MS) technique. The tests were subjected to two types of binders from different manufacturers. Among the products of pyrolysis there have been identified mainly benzene and its derivatives, and phenol and its derivatives. Compounds identified in pyrolytic gas are largely considered to be harmful to humans and the environment (some of the compounds are carcinogenic and mutagenic). The presented results of the TG–GC–MS measurements show that the applied analytic methods are feasible to perform a qualitative and also quantitative characterization of the binder samples

Zinc ferrite nanoparticles as perspective functional materials for applications in casting technologies

In this article it discuss on possible application of magnetic oxide nanoparticles, namely non-stoichiometric zinc ferrite nanoparticles as a functionalizing agent in foundry processes. Thermal analysis showed a weight loss of the sample at 1 273 K in an amount of 7,7 %, which is a result of the following processes taking place in different temperature ranges. Upon its thermal treatment Zn_0,4Fe_2,6O₄ decomposes to zinc oxide and iron (III) oxide (first stage) and next to iron (II,III) oxide and oxygen (second stage). The degree of decomposition was expressed as Fe²⁺ / Fe_total. Mössbauer spectroscopy showed that the over 30 % of Fe³⁺ present in starting material was reduced to Fe²⁺

State space analysis of sleep after traumatic brain injury in rats

Objectives: Sleep-wake disturbances occur frequently after traumatic brain injury (TBI). Therefore, we aimed at studying the dynamic features of sleep after severe TBI in a rat model of traumatic brain injury. Methods: We obtained 24 h encephalographic recordings at different time points after TBI and analyzed the signal using a novel frequency based EEG analysis technique (state space analysis). In this quantitative sleep analysis approach, velocity in state space represents behavioral state instability. Results: We found a significantly higher mean velocity of slow wave sleep 7 days after TBI as compared to the control group (p=0.04, 2-sided t-test). This transient effect was no longer seen after 28 days and was not observed in the control group. Conclusions: The observed short-lasting elevation of state space velocity can be interpreted as a transient sleep state instability after TBI. These results shed a new light into the dynamics of pathological changes of sleep architecture after TBI that are not identified by conventional scoring and analysis techniques

Fraser syndrome and mouse blebbed phenotype caused by mutations in FRAS1/Fras1 encoding a putative extracellular matrix protein.

Fraser syndrome (OMIM 219000) is a multisystem malformation usually comprising cryptophthalmos, syndactyly and renal defects. Here we report autozygosity mapping and show that the locus FS1 at chromosome 4q21 is associated with Fraser syndrome, although the condition is genetically heterogeneous. Mutation analysis identified five frameshift mutations in FRAS1, which encodes one member of a family of novel proteins related to an extracellular matrix (ECM) blastocoelar protein found in sea urchin. The FRAS1 protein contains a series of N-terminal cysteine-rich repeat motifs previously implicated in BMP metabolism, suggesting that it has a role in both structure and signal propagation in the ECM. It has been speculated that Fraser syndrome is a human equivalent of the blebbed phenotype in the mouse, which has been associated with mutations in at least five loci including bl. As mapping data were consistent with homology of FRAS1 and bl, we screened DNA from bl/bl mice and identified a premature termination of mouse Fras1. Thus, the bl mouse is a model for Fraser syndrome in humans, a disorder caused by disrupted epithelial integrity in utero