Comparative Chemical Analysis of the Extractives Constituents in the Bark and Heartwood of Juglans regia L. from North of Iran

Exhaustive ethanol-toluene of the bark and heartwood of Juglans regia L. (Juglandaceae) afforded pale red colored extractives 10 and 12% yields, respectively. Detailed chemical evaluation of these extracts using GC/MS revealed the major components in the bark and heartwood extractives to be the 3,7-dioxa-2,8- disilanonane,2,2,8,8-tetramethyl (25.17%), while the major heartwood extractives constituent was benzoic acid, 3,4,5-tri(hydroxyl)/Gallic acid (44.57%). The same components of the bark and the heartwood also contained amounts of the gallic acid, 3,7-dioxa-2,8-disilanonane, 2,2,8,8- tetramethyl, and d-glucose,2,3,4,5,6- pentakis-o-(hydroxyl). The most toxic components in the heartwood were juglone (5.15%) and 2,7-dimethylphenanthrene (5.81%)

Utjecaj predimpregnacije anhidridom octene kiseline i vremena zagrijavanja na mehanička i fizička svojstva drvno-plastičnih kompozita

This research aimed to assess the influence of different pre-impregnation times (PITs) (60, 180, and 300 min), heating or reaction times (H/RTs) (60, 90, and 120 min), and chemical modification of wood flour (WF) on the mechanical and physical properties of wood-plastic composites (WPCs). The study employed acetylated beech (Fagus orientalis L.) flour as the filler and polypropylene (PP) as the matrix phase producing of WPC samples through melt compounding and injection molding. The resulting composites underwent testing for their physical and mechanical properties. The findings revealed that WPCs derived from acetylated wood with PITs of 60 min and H/RTs of 60 min exhibited the highest mechanical properties, except for the bending modulus. Moreover, the lowest water absorption (WA) was observed in the PITs-H/RTs combination of 60-120 min, while the lowest thickness swelling (TS) occurred in the PITs-H/RTs combination of 300-60 min. The simultaneous utilization of pre-impregnation and reaction times demonstrated a synergistic effect on the physical and mechanical properties. Consequently, the chemical modification of wood flour and the application of suitable reaction times improved the interfacial adhesion, thereby enhancing the overall performance of the WPCs.Cilj ovog istraživanja bio je procijeniti utjecaj različitih vremena predimpregnacije (PIT) (60, 180 i 300 min), vremena zagrijavanja (H/RT) (60, 90 i 120 min) i kemijske modifikacije drvnog brašna (WF) na mehanička i fizička svojstva drvno-plastičnih kompozita (WPC). U istraživanju je za proizvodnju uzoraka WPC-a taljenjem i injekcijskim prešanjem upotrijebljeno drvno brašno acetilirane bukovine (Fagus orientalis L.) kao punilo i polipropilen (PP) kao matrica. Zatim su ispitana fizička i mehanička svojstva dobivenih kompozita. Rezultati su pokazali da drvno-plastični kompoziti dobiveni od acetiliranog drva s vremenom predimpregnacije i zagrijavanja od 60 min imaju najbolja mehanička svojstva, osim modula na savijanje. Nadalje, najmanje upijanje vode (WA) zabilježeno je za kombinaciju PIT-H/RT 60-120 min, dok je najmanje debljinsko bubrenje (TS) izmjereno za kombinaciju PIT-H/RT 300-60 min. Istodobno je primjena predimpregnacije i zagrijavanja pokazala sinergijski utjecaj na fizička i mehanička svojstva. Posljedično su kemijska modifikacija drvnog brašna i odabir odgovarajućih vremena zagrijavanja poboljšali adheziju između faza, a time i svojstva drvno-plastičnih kompozita

Kemijska karakterizacija biološkog ulja dobivenoga pirolizom zdravoga i natrulog drva bukve (Fagus orientalis)

Among forest diseases, fungi are the most important agents that cause irreparable losses to the wood of standing trees and logs. In this study, pyrolysis of undecayed and decayed beech (Fagus orientalis) wood were carried out using a fixed-bed reactor at pyirolysis temperature of 500 °C in nitrogen atmosphere. The influence of Trametes versicolor fungal decay on the yield and chemical composition of products was investigated. The bio-oil yield was 62.5 wt% at a pyrolysis temperature of 500 °C for decayed wood, while the bio-oil yield was found to be about 58 wt% at the same temperature for undecayed wood. Bio-oils were characterized using some chromatographic and spectroscopic techniques, such as gas chromatography-mass spectrometry (GC/MS). It as found that Tetracosamethyl-cyclododecasiloxane (5.50 %), tetradecamethyl-hexasiloxane (4.85 %), 2,6-dimethoxy-phenol (4.21 %), and benzene acetic acid (3.16 %) were the main oil components present in decayed beech wood, while syringol (14.86%), methoxyeugenol (6.59 %), naphthalene (4.41 %), o-guaiacol (3.60 %), isoeugenol (3.17 %), and 2-methoxy-4-methyl-phenol (3.08 %) were present in undecayed beech wood. These results show that decayed wood can be used for the production of bio-oil.Među šumskim štetnicima gljive su najopasniji činitelji koji uzrokuju nepovratne gubitke drva rastućih stabala i trupaca. U ovom je istraživanju provedena piroliza uzoraka od zdravoga i natrulog drva bukve (Fagus orientalis) u atmosferi dušika, uz pomoć fiksnog reaktora i pri temperaturi pirolize 500 °C. Istraživan je utjecaj gljiva truležnica (Trametes versicolor) na prinose i kemijski sastav produkata pirolize tretiranog drva. Prinos biološkog ulja od natrulog drva pri temperaturi pirolize 500 °C bio je 62,5 % (težinskog udjela), dok je prinos biološkog ulja od zdravog drva bio oko 58 % (težinskog udjela) pri jednakoj temperaturi pirolize. Biološkog ulja su karakterizirana uz pomoć određenih kromatografskih i spektroskopskih tehnika kao što je plinska kromatografija / masena spektrometrija (GC/MS). Utvrđeno je da su glavne uljne komponente zastupljene u natruloj bukovini tetracosametilciklododekasiloksan (5,50 %), tetradekametil heksasiloksan (4,85 %), 2,6-dimetoksi-fenol (4,21 %) i benzen octena kiselina (3,16 %), dok je u zdravom bukovu drvu bilo siringola (14,86 %), metoksieugenola (6,59 %), naftalena (4,41 %), o-gvajakola (3,60 %), izoeugenola (3,17 %) i 2-metoksi-4-metilfenola (3,08 %). Dobiveni rezultati pokazuju da se natrulo drvo može iskoristiti za proizvodnju biološkog ulja

Brzina dugotrajnoga higroskopskog debljinskog bubrenja kompozita od polipropilena i hidrotermički tretirane bukovine

Long-term hygroscopic thickness swelling rate of polypropylene (PP) composites filled with thermally treated wood flour was investigated. The beech wood chips were heat treated at 120 °C, 150 °C or 180 °C for 30 or 120 min using saturated steam in a digester. The composites based on PP, beech wood flour (BF), and coupling agents (PP-g-MA) were made by melt compounding and injection molding. The weight ratio of BF to PP was controlled at 50/47 for all blends. The amount of coupling agent was fixed at 3 wt.% for all formulations. Further study was conducted to model thickness swelling of the composites, a swelling rate parameter (KSR). The thickness swelling of thermally-treated samples at 120 ºC for 30 min and at 150 ºC for 30 min were lower than that of control samples, followed by thermally-treated samples at 180 ºC for 120 min, at 180 ºC for 30 min, at 120 ºC for 120 min, and at 150 ºC for 120 min, respectively. Furthermore, the thickness swelling of the BF/PP composites decreased with increasing time and temperature of the thermal-treatment. In addition, at 120 ºC for 30 min, the composites showed a lower swelling rate than control samples. The KSR of the composites was influenced both by the time and temperature of thermal treatment.U radu je istražen dugotrajni stupanj higroskopskoga debljinskog bubrenja polipropilenskih (PP) kompozita punjenih toplinski obrađenim drvnim brašnom. Iverje od bukovine bilo je toplinski tretirano na 120, 150 ili 180 °C tijekom 30 ili 120 minuta uz pomoć zasićene pare u digestoru. Kompoziti na bazi PP-a, brašna od bukovine (BF)-a i veziva (PP-g-MA) izrađeni su taljenjem i injekcijskim prešanjem. Maseni je omjer BF/PP za sve smjese bio 50/47. Količina veziva za sve formulacije bila je na 3 wt.%. Nadalje, provedeno je modeliranje debljinskog bubrenja kompozita i parametra brzine bubrenja (KSR). Debljinsko bubrenje uzoraka toplinski tretiranih 30 min na 120 ºC i 30 min na 150 ºC bilo je niže nego na kontrolnim uzorcima, zatim slijede uzorci toplinski tretirani 120 min na 180 ºC, 30 min na 180 ºC, 120 min na 120 ºC, odnosno 120 min na 150 ºC. Nadalje, debljinsko bubrenje BF/PP kompozita smanjivalo se s povećanjem vremena i temperature toplinskog postupka. Osim toga, kompoziti su pri 30 min na 120 ºC pokazali niži parametar brzine bubrenja od kontrolnih uzoraka. Na parametar brzine bubrenja kompozita utjecali su vrijeme toplinskog tretmana i temperatura

Physical, mechanical and thermal properties of wood/zeolite/plastic hybrid composites

Effect of zeolite content on the physical, mechanical and thermal properties of wood plastic composites was investigated in this study. To meet this objective, pine wood flour (0, 10, 20, 30, 40, 50 wt%) with compatibilizing agent, zeolite (0, 10, 20, 30, 40, 50 wt%), and polypropylene were compounded in a twin screw co-rotating extruder. The mass ratio of the wood flour to polypropylene was 50/50 (w/w) in all compounds. Test specimens were produced using injection molding machine from the pellets. Physical and mechanical, and thermal (Thermogravimetry Analysis/Differential Scanning Calorimetry) properties of the wood plastic composites were determined. The water absorption and thickness swelling properties of wood plastic composites improved with increasing zeolite content. The flexural and tensile properties of the wood plastic composites decreased with increasing zeolite content. All the wood plastic composites provided the values of flexural strength (58,4-72,9 MPa) and flexural modulus (2718-5024 MPa) that were well over the requirement by the standard specified in ASTM D 6662. The mass loss rates values of wood plastic composites increased with increasing zeolite contents. The Differential Scanning Calorimetry analysis showed that the melt crystallization enthalpies and degree of crystallization of wood plastic composites decreased with increasing zeolite content. The decrease in the Tc and Xc indicated that zeolite was the poor nucleating agent for the wood plastic composites

Laboratory Study of Synergistic Effects of Mixtures of Organic Biocides, Metal Chelator and Antioxidant Materials against Rainbow White-rot Fungus

In this research, the individual and interaction effects of three organic biocides (propiconazole, tebuconazole, and chlorothalonile) with the metal chelator EDTA and the antioxidant BHT at different concentrations (50, 150, 250, 350, and 450 ppm) against the white-rot fungus, Trametes versicolor was investigated. In under laminar sterile hood, about 25 mL of the media was poured into the Petri plates. Three antibiogram discs (with triangular position) put on the media. By micro-sampler about 20 μL of steriled preservative solutions was poured on every disc, separately. Then, about 5 mm of mycelium plug of intended fungus that was inoculated previously was put in the center of plates. The plates were incubated and daily for one week, the mycelium growth of fungus and inhibition effects of different preservative solutions against fungus was measured. The results of this research demonstrated that chlorothalonil biocide by itself have not any inhibition effect on growth of fungus, whilst propiconazole and tebuconazole biocides by itself have significant effect at different concentrations on growth of fungus. In consider of synergistic effect of propiconazole, tebuconazole, and chlorothalonil biocides with non-biocides additives of EDTA and BHT, it has been found that there is synergistic effect between propiconazole biocide and the metal chelator EDTA at high concentration such as 450 ppm, but in combination with other solutions synergistic effect has not been found. Also, any synergistic effect has not found between tebuconazole and chlorothalonil biocides with other preservative solutions

Heartwood Extractives of Robinia pseudoacacia Wood

In this study, extracts from the heartwood of black locust (Robinia pseudoacacia L.) were obtained with ethanol solvent before and after extraction with n-hexane. Chemical composition were analyzed and compared by GC-MS. The results showed that the major components in the heartwood ethanol extract before extraction with n-hexane solvent to be the (23S)-ethylcholest-5-en-3.beta.-ol (18.33%), while the major heartwood ethanol extracts constituents after extraction with n-hexane solvent was resorcinol (51.96%). The same components of the heartwood ethanol extracts before and after extraction with n-hexane solvent also contained amounts of the Hexadecanoic acid and 9,12-Octadecadienoic acid (Z,Z)-. The other main components of the ethanol extracts mainly contained about 13.75% stigmasterol, 9.35% 9,19- Cyclolanostan-3-ol, 24-methylene-, (3.beta.)-, 7.11% Lup-20(29)-en-3- one, 6.27% 9,12,15-Octadecatrien-1- ol, (Z,Z,Z)-, 6.06% Hexadecanoic acid 4.54% Ergost-5-en-3-ol, (3.beta.)-, and 3.53% campesterol

Chemical Composition and Antioxidant Activity of Extracts from the Fruit, Leaf, and Branchlet of Cupressus arizonica Greene

Potent antioxidant activities of solvent extracts (96% aqueous ethanol) from the fruit, leaf, and branchlet without adherent leaf of Cupressus arizonica were evaluated using the 1,1-diphenyl-2-picrylhydrazyl (DPPH) assay and compared with butylated hydroxytoluene (BHT) and ascorbic acid (AA). Their chemical compositions were analyzed using gas chromatography-mass spectrometry (GC/MS). Branchlet extracts (BE) were the most active as an antioxidant agent at 93.3% at the concentration of 0.493 mg/mL, which was higher than the value of vitamin C (63.3%) at the same concentration. The major components identified in the BE were communic acid (43.7%), followed by agatholic acid (20%), and ferruginol (10.4%). The extract from fruit had good antioxidant activity (90.3%) at a concentration of 0.015 mg/mL. The major compounds identified in the fruit extracts (FE) were communic acid (46.8%), spirohexane-5-carboxylic acid, 1,1,2,2-tetramethyl-, methyl ester (27.4%), and ferruginol (6%). Leaf extracts (LE) were more active as an antioxidant agent at 80.3%, which was higher than the value of BHT (75.7%) at the concentration of 0.015 mg/mL. The major components identified in the LE were hexadecanoic acid (45.1%), 1H,5H-pyrrolo[1',2':3,4]imidazo[1,5-a]pyridine, octahydro- (9%), bicyclo [3.1.0]hex-3-en-2-one, 4-methyl-1-(1-methylethyl)- (8.1%)