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Glue-bond strength of simul (Bombax ceiba) plywood made of Neem (Azadiracta indica) leaves treated veneers
2013 - IRG/WP 13-40647
The glue-bond qualities of plywood made of treated simul (Bombax ceiba) veneers were investigated. The veneers were treated with cold and hot water solution of neem (Azadiracta indica, A. Juss.) leaves of different concentrations and treatment durations. The plywoods were made at three different pressures in hot press using urea formaldehyde glue. The glue-bond strength of untreated simul plywood in dry shear-test were found to be 2.17 and 2.29 N/mm2 made at 1.05 and 1.40 N/mm2 pressure respectively. It was observed that the glue-bond strength of neem leaves cold water treated (1:10) simul plywood in dry shear-test were 2.01 to 2.29 N/mm2 made at 1.05, 1.40 and 1.76 N/mm2 pressure. It was found that the values of load at failure of treated simul plywood in dry shear-test were gradually decreased with the increasing treatment duration and concentration of solution. For maximum treatments, lower values of shear strength were observed in plywood made of hot water-treated veneer compared to that of cold water-treated veneer. However, the values of glue bond strength in all Neem Leaves (NL) treated plywood met ‘A-grading’ requirement for gluing.
K Akhter, M A Hashem, S Akhter

Agar block durability test of plywood made of neem (Azadiracta indica) leaves treated veneer using two white rot fungi
2017 - IRG/WP 17-40782
This study has been undertaken to investigate the durability of plywood made from non-durable wood (simul, Bombax ceiba) veneer treated by neem (Azadiracta indica, A. Juss.) leaves. The veneers were treated with cold and hot water solution of neem leaves of different concentrations (10%, 5%, 2.5%) and treatment durations (1, 2, 3 days) for cold water and 20, 40 and 60 minutes for hot water. The plywood were made at three different pressures 1.05, 1.40, 1.76 N/mm2 in hot press using urea formaldehyde glue. Durability were investigated with pure cultures of two wood destroying white rot fungi Phanerochaete chrysosporium (Pc) and Ceriporiopsis subvermispora (Cs). After 16 weeks exposure, weight losses of 22.55-20.87 % were obtained in plywood samples treated with 10 % neem leaves in cold water. Weight losses of 29.71-26.92 % were obtained in plywood samples treated with 5% neem leaves- cold water. The plywood samples made of treated veneers with 1:10 (10%) neem leaves in hot water had average weight losses of 22.5-25.5%. In the present study, weight losses of 25.47 and 22.31 % was obtained in plywood samples treated with 10 % neem leaves in hot water. Weight losses of 34.49-30.77 % were obtained in plywood samples treated with 5% neem leaves-hot water. The percentage of weight losses observed in control plywood samples was ranging from 55 to 66. In all the cases, the analysis of variance showed significant difference among the time period & concentration 1:10, 1:20 and 1:40. After mycological test, the treated samples were classified according to British standard BS EN 350-1 (1994a) and 10 % neem leaves treated samples found moderately durable.
K Akhter, M A Hashem, S Akhter

Sterilization of mango wood (Mangifera indica L.) without heat
1995 - IRG/WP 95-30065
Researches revealed that boric acid can play an important role for sterilizing wood instead of heating. Wet (green) mango boards (Mangifera indica L.) were pressure treated in treating cylinder at initial vacuum of 508 mm Hg for 15 minutes and impregnation pressure of 7 kg/cm² for 4 hours with 5% solution (w/v) of 1:1:1 commercial grade (95% pure) sodium dichromate, copper sulphate and boric acid. Penetratons of copper sulphate and boric acid were examined by using standard reagents. Copper sulphate penetrated superficially but boric acid penetrated completely through the boards. In most hazardous conditions during rainy season the treated boards were saved like heatsterilized boards from the attack of decay fungi and insects. Untreated boards (control) were found decayed and damaged within three months with the decrease of strength significantly. Where heatsterilization and kiln-drying are practically impossible during rainy season, wet timbers can be stored after impregnating those with at least 2% solution (w/v) of boric acid which diffuses through wet wood successfully and can protect wood from decay fungi, and wood destroying borers.
A K Lahiry

IRG/COIPM INTERNATIONAL MARINE TEST - to determine the effect of timber substrate on the effectiveness of water-borne salt preservatives in sea-water. Progress Report 21: Report of eighth inspection (7 years) in Australia
1985 - IRG/WP 4119
This report tabulates the seven year (86 month) inspection results, obtained on 28 Fabruary l985, of the IRG/COIPM International Marine Test at Goat Island, Australia. This test was installed in December 1977. The results are given in Tables 1-6. Table 7 lists the number of marine borers identified from blocks (2 cm and 6 cm long respectively) cut from the ends of specimens removed at the previous inspection, i.e. after 72 months. At that inspection the central portion of the specimens removed from test were used for chemical analysis, and bacterial and soft rot assessment by various IRG researchers. Limnoria quadripunctata has been previously identified from other timbers treated with copper-containing preservatives (Barnacle et al., 1983). Limnoria indica had not been identified previously from Australia, and this occurrence together with additions to the description of the borer, will be given by Cookson (in preparation).
L J Cookson, J E Barnacle

The performance in the sea of seven experimental piles after sixteen years at Port Douglas, North Queensland
1989 - IRG/WP 4151
After 16 years at Port Douglas, two double-treated Pinus radiata piles were in excellent condition, a CCA-treated Pinus elliottii pile was in good condition other than for a confined streak of teredinid attack, while two CCA-treated and two untreated turpentine piles were moderately to severely attacked by Sphaeroma in the tidal zone. The marine borers collected were Sphaeroma terebrans, Martesia striata, Lyrodus sp., Teredo sp., Limnoria unicornis, Limnoria indica and Limnoria insulae.
L J Cookson, J E Barnacle, C N McEvoy

Borer fauna of Iran biodeterioration of wooden boats in Persian Gulf and Sea of Oman
1997 - IRG/WP 97-10230
In Persian Gulf and Sea of Oman (Indian Ocean) there are thousands of wooden boats from the time of Acheamenian and Sassand dynasti when India was a part of the Persian Empire. Now after 2500 years again, the Indian timbers specially Tectona Grandis and other Indian timbers and also tropical woods of Zanzibar (Tanzania) are brought to the Persian Gulf and Sea of Oman (Indian Ocean). Unfortunately the woods are not pressure impregnated but the boats are made from many kinds of woods (indigenous and exotic) and with bad oil impregnation (local impregnation). As a result the wooden boats are very badly attacked by different borers. None of the timber species currently in demand for boat building possesses any natural bioresistance, and will be completely destroyed within 6 to 12 months. The Iranian ministry of Jihad (reconstruction) should use pressure impregnation of wood with preservative chemicals, but the impregnation is inadequate. The need for long-term research in the field of marine biodeterioration for improving the efficiency of currently known control measures, with emphasis of application of non-polluting biological methods has been suggested in this paper.
P Niloufari

Non-pressure preservation technique of five less durable timber species – Kadam (Anthocephalus cadamba), Shimul (Bombax ceiba), Pithalu (Trewia nudiflora), Am (Mangifera indica) and Boroi (Ziziphus jujube) of Bangladesh
2006 - IRG/WP 06-40322
Wood is a versatile renewable resource, which has been extensively used as a reliable construction material as well in furniture ever since the beginning of civilization. The Major disadvantage of wood is its susceptibility to biodeterioration by fungi, insects and bacteria. In tropical countries like Bangladesh, fungi is the most significant of these biodeterioration agents. Kadam (Anthocephalus cadamba), Shimul (Bombax ceiba), Pithalu (Trewia nudiflora), Am (Magnifera indica), and Boroi (Ziziphus jujube) are five, local and available, useful but less durable timber species of Bangladesh. The heartwood of these timber species is more or less resistant to decay and insects, but sapwood faces quick deterioration while exposed to moisture and wood enemies. On the other hand, wood can be protected from attacks from these enemies with the appropriate preservative treatment, by reducing or changing the form of its food toxic to wood enemies. So, appropriate preservative treatment is required to increase the durability of these timber species. The study of chemical preservative treatment of these five timber species has been undertaken using a mixture of Chromate-copper-boron (CCB) at 2:2:1 ratio with four different concentrations of 4, 6, 8 and 10% and different treatment durations of 8, 16 and 24 hours by non-pressure dipping method. It has been observed that Pithalu showed comparatively higher preservative retention than other four species, which indicates that Pithalu is a permeable and diffuse specie for dipping method. A preservative penetration test provided the information that air dried wood samples using 10% preservative concentration with 8 hour and 24 hours duration of dipping gave the best result for copper, while 10% preservative concentration with 24 hours duration used on green wood has shown the best result for boron penetration. The major physical properties of wood viz., moisture content, density and shrinkage have also been studied. Anthocephalus cadamba showed a lower density, while Ziziphus jujube had a higher density. Bombax ceiba and Trewia nudiflora are very close to Anthocephalus cadamba and Magnifera indica is very close to Ziziphus jujube with respect to the moisture content. Bombax ceiba, Trewia nudiflora and Magnifera indica showed all moderate positions with respect to density.
G N M Ilias, A H Kabir, F Begum, M F Alam

Efficacy of Neem (Azadirachta indica) Leaves Against Wood Decay Fungi
2008 - IRG/WP 08-30450
Many plant-derived substances have fungitoxic, pecticidal and insecticidal ability. Neem leaves are very popular in this respect since the ancient time. The present study is to investigate the fungitoxic activities of neem leaves extractives against wood decay fungi. Three different solvents, i.e. acetone, methyl alcohol, ethyl alcohol, were used to isolate the extract of neem leaves. The extractives were then used to see the inhibition acitivity over the test fungi in laboratory and natural condition. Both results proved that 3% concentration of acetone extract is best for inhibiting the growth of test fungus. Acetone and methanolic extract was also effective against that decay fungus. From this investigation, it is established that neem extract is potential source of biological preservative of wood and it can be used in any wood related commercial purposes.
A Humayan Kabir, M A Rahman, M Firoz Alam

Quercetin - a potential compound of Azadirachta indica A. Juss. (Neem) leaves exhibiting activity against wood decaying fungi and termites
2008 - IRG/WP 08-30463
Azadirachta indica A.Juss. is widely recognized for its medicinal, insecticidal, pesticidal and anti-microbial property. Methanol extract of neem leaves revealed marked anti-fungal activity when subjected to malt-agar and soil block bioassay against wood destroying brown (Oligoporus placentus) and white rot (Trametes versicolor). The extract also revealed marked termicidal property when subjected to wood destroying termites i.e. Microcerotermes beesoni Synder in laboratory and against Odentotermes obesus Rambur in termite mound. Column chromatography of methanol extract resulted in isolation of compound exhibiting potential activity against fungi. The compound obtained was identified as flavanoid and structure elucidation was done by UV-Visible, IR, Mass, 1H & 13C NMR. The compound was identified as quercetin. It was further tested at 5µg concentration exhibiting 100% growth retardation of the test fungi.
S Dhyani, S Tripathi

Potenzy of Azadirachta indica heart wood extracts as wood bio-preservative against termite attack
2020 - IRG/WP 20-10972
Extractives in wood are one of the main reasons for wood resistance against bio-degradation. The chemical compositions of extractives from matured Azadirachta indica that are known to be very resistant against bio-degradation were studied to assess their role as wood preservative. Ethanol and toluene were used in the extraction of these compounds from the heartwood of Azadirahcta indica. Chemical analysis of the extracts was done using Gas Chromatography-Mass Spectrometry (GC-MS) after derivatization using N,O bis (trimethyl silyl) acetamide. The main groups of compounds identified from both extracts are fatty acids, hydrocarbons, sterols, sterol ketones, phenolics, sterol esters and waxes. The extracts obtained were used to treat sapwood of four different wood species that are known to be susceptible to bio-degradation at 12% (weight/weight) retention level. Treated samples were taken to timber graveyard for 12 months. It was observed that the extracts from Azadirachta indica used improved the resistance of these susceptible wood species to termite attack at the timber graveyard more than 70% when compared to the controls and also it was observed that removal of extractives from Azadirahcta indica significantly decreased their resistance to termite attack. Conclusively, the extractives from Azadirachta indica wood contribute greatly to the protection of susceptible wood species against termite attack.
L O Aguda, O B Olajide, O Y Aguda