The article presents preliminary results of the biological durability of oil heat treated (OHT) alder wood (Alnus glutinosa) against pure cultures of rot fungi (Postia placenta and Trametes ...versicolor) in lab conditions. The modification was performed by heating of specimens immersed in soya oil. There were four heating regimes of different duration (6 and 10 hours) at final temperature of 180 and 200 ºC. The increase in mass (MI) caused by modification and mass loss of wood caused by fungal decay (ML) were determined. In addition, the natural durability of alder wood was determined and compared to the natural durability of beech wood as the reference wood species. After modification of alder wood at 200 °C, MI was lower than after treatment at 180 °C. MI was also lower after 10 hours of treatment than after 6 hours of treatment. The results showed significantly increased biological durability of modified alder wood against both tested fungi. The effect of OHT on increasing the biological durability of alder wood was higher against the fungus P. placenta. It seems that the fungus T. versicolor favours the remained oil after modification causing higher mass loss. The results showed that alder wood, thermally modified in soya oil by testing regimens, is not suitable for applications in use classes 3-5.
This paper presents the results of measurement of durability of beech wood (Fagus sylvatica) modified by Citric Acid (CA) against brown rot fungus Poria placenta according to EN 113. Modification was ...performedby impregnation with 7.0% CA and 6.5% sodium-hypophosphite (SHP) water solution and 10-hour curing at 140 °C. The influence of thermal treatment on durability was also researched. Weight percentage gain (WPG) caused by modification, moisture content (MC) and mass loss of wood (dm) after fungal nutrition were measured. WPG of modified beech wood was 6.1% and that of thermally treated wood was -0.3%. The results showed increased durability of modified wood to be 8.3 times greater than nonmodified, while thermal treatment did not give significant durability improvement. These results indicate modification by CA as a promising alternative, but further research on optimisation of modification parameters is needed to achieve improvement of wood properties.
The aim of this study was to test the value of computed tomography (CT)-guided endoscopy in the scientific study of mummified remains and the recovery of unidentified objects from ancient mummified ...remains. CT-guided endoscopy was performed on an Egyptian mummy from the Late Period to help retrieve an unidentified object from its skull. The combined use of CT and endoscopy facilitated the recovery of the object, minimizing further damage to the remains and to the object itself. The successful recovery of the brittle object allowed detailed analysis of the item to be performed in an attempt to determine the nature of its presence in the cranial cavity. It was confirmed that the object was a monocotyledon stem fragment. Relying on the existing literature on mummification and excerebration methods in ancient Egypt, we concluded that the stick was probably used for transnasal removal of the brain. The results of this study demonstrate the great potential of CT-guided endoscopy for minimally invasive recovery of small unidentified items from mummies that could yield important information about mummification procedures and the materials used to preserve bodies.
U radu su prezentirani preliminarni rezultati biološke otpornosti drva johe (Alnus glutinosa) termički modificiranoga u sojinu ulju protiv čistih kultura gljiva truležnica (Postia placenta i Trametes ...versicolor) u laboratorijskim uvjetima metodom mini blok prema CEN TS 15083-1. Modifikacija je izvedena zagrijavanjem uzoraka uronjenih u sojino ulje sobne temperature. Četiri načina termičke modifikacije razlikovala su se po trajanju držanja drva (6 i 10 sati) na konačnoj temperaturi (180 i 200 ºC). Usto je određena i prirodna otpornost johovine u usporedbi s prirodnom otpornosti bukovine kao referentne prirodno slabo otporne vrste drva. Mjereno je povećanje mase modifikacijom (DMM) i gubitak mase djelovanjem spomenutih gljiva (GMG). Nakon modifikacije pri višoj temperaturi DMM drva johe bio je manji nego nakon modifi kacije pri nižoj temperaturi. Slično tome, dulji je tretman rezultirao nižim DMM-om nego kraći tretman. Rezultati su potvrdili povećanje biološke otpornosti modificirane johovine protiv obje testirane gljive truležnice. S povećanjem temperature modifikacije znatno se povećava biološka otpornost protiv obje gljive, dok produljenje vremena zagrijavanja ima blagi učinak povećanja biološke otpornosti. Utjecaj modifikacije na povećanje biološke otpornosti veći je protiv gljive smeđe truleži P. placenta. Utvrđeno je da je veći gubitkom mase modificiranih uzoraka djelovanjem gljive T. versicolor (u usporedbi s gubitak mase djelovanjem gljive P. placenta) najvjerojatnije nastao zbog razaranja preostalog ulja u drvu nakon modifikacije. Dokaz tome je crvena boja mikroskopskih preparata modificiranih uzoraka (postojanje lignina) te lokalna plava obojenost u lumenima traheja (nedostatak lignina). U lumenima traheja ostalo je najviše ulja nakon modifi kacije, pa se tu ujedno i najjače razvio micelij gljive bijele truleži T. versicolor, koji je, osim razgradnje ulja, djelomično uništio i lignin. Rezultati su pokazali da johovina termički modificirana u biljnom ulju, prema testiranim režimima, nije primjerena za upotrebu u razredima opasnosti 3 i višima.
The article presents preliminary results of the biological durability of oil heat treated (OHT) alder wood (Alnus glutinosa) against pure cultures of rot fungi (Postia placenta and Trametes ...versicolor) in lab conditions. The modification was performed by heating of specimens immersed in soya oil. There were four heating regimes of different duration (6 and 10 hours) at final temperature of 180 and 200°C. The increase in mass (MI) caused by modification and mass loss of wood caused by fungal decay (ML) were determined. In addition, the natural durability of alder wood was determined and compared to the natural durability of beech wood as the reference wood species. After modification of alder wood at 200°C, MI was lower than after treatment at 180°C. MI was also lower after 10 hours of treatment than after 6 hours of treatment. The results showed significantly increased biological durability of modified alder wood against both tested fungi. The effect of OHT on increasing the biological durability of alder wood was higher against the fungus P. placenta. It seems that the fungus T. versicolor favours the remained oil after modification causing higher mass loss. The results showed that alder wood, thermally modified in soya oil by testing regimens, is not suitable for applications in use classes 3-5. Key words: durability class, Postia placenta, soya oil, Trametes versicolor, use class U radu su prezentirani preliminarni rezultati bioloske otpornosti drva johe (Alnus glutinosa) termicki modificiranoga u sojinu ulju protiv cistih kultura gljiva truleznica (Postia placenta i Trametes versicolor) u laboratorijskim uvjetima metodom mini blok prema CEN TS 15083-1. Modifikacija je izvedena zagrijavanjem uzoraka uronjenih u sojino ulje sobne temperature. Cetiri nacina termicke modifikacije razlikovala su se po trajanju drzanja drva (6 i 10 sati) na konacnoj temperaturi (180 i 200°C). Usto je odredena i prirodna otpornost johovine u usporedbi s prirodnom otpornosti bukovine kao referentne prirodno slabo otporne vrste drva. Mjereno je povecanje mase modifikacijom (DMM) i gubitak mase djelovanjem spomenutih gljiva (GMG). Nakon modifikacije pri visoj temperaturi DMM drva johe bio je manji nego nakon modifikacije pri nizoj temperaturi. Slicno tome, dulji je tretman rezultirao nizim DMM-om nego kraci tretman. Rezultati su potvrdili povecanje bioloske otpornosti modificirane johovine protiv obje testirane gljive truleznice. S povecanjem temperature modifikacije znatno se povecava bioloska otpornost protiv obje gljive, dok produljenje vremena zagrijavanja ima blagi ucinak povecanja bioloske otpornosti. Utjecaj modifikacije na povecanje bioloske otpornosti veci je protiv gljive smede trulezi P. placenta. Utvrdeno je da je veci gubitkom mase modificiranih uzoraka djelovanjem gljive T. versicolor (u usporedbi s gubitak mase djelovanjem gljive P. placenta) najvjerojatnije nastao zbog razaranja preostalog ulja u drvu nakon modifikacije. Dokaz tome je crvena boja mikroskopskih preparata modificiranih uzoraka (postojanje lignina) te lokalna plava obojenost u lumenima traheja (nedostatak lignina). U lumenima traheja ostalo je najvise ulja nakon modifikacije, pa se tu ujedno i najjace razvio micelij gljive bijele trulezi T. versicolor, koji je, osim razgradnje ulja, djelomicno unistio i lignin. Rezultati su pokazali da johovina termicki modificirana u biljnom ulju, prema testiranim rezimima, nije primjerena za upotrebu u razredima opasnosti 3 i visima. Kljucne rijeci: Postia placenta, razredi opasnosti, razred trajnosti, sojino ulje, Trametes versicolor
Gamma irradiation, which is an easy, fast and effective method for wood sterilisation, changes molecular structures not only in pest cells, but also in wood cell walls. Radiation-induced ...depolymerisation causes significant changes in some properties of wood crucial for restoration and for laboratory testing of wood-preservative effectiveness, as demonstrated by experimental data. The influence of gamma radiation on maximum swelling (αMAX), resistance to impact milling (RIM), and the total amount of water-soluble carbohydrates (TSC) was investigated. Cobalt (60Co) was used as a gamma source and Scots pine wood (Pinus sylvestris L.) was irradiated at doses of 30, 90 and 150 kGy. A strong linear correlation was found between TSC and radiation dosage. Leached irradiated specimens showed significantly greater TSC content than non-irradiated controls. RIM decreased significantly and linearly with increasing radiation dosage. After leaching, the linearity between these parameters improved. Gamma radiation had no significant effect on αMAX and the time elapsed after irradiation did not influence αMAX, RIM or TSC.
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