Low permeability of many wood species due to their anatomical properties causes problems during timber drying as well as impregnating with preservatives and resins. Microwave (MW) treatment influences heartwood permeability and improves preservative uptake and distribution. In the present study, microwave treatment of chir pine (Pinus roxburghii) wood was done at 2,45 GHz frequency at different level of intensity and radiation time. The gas permeability of chir pine wood was measured in an in-house built apparatus. Preservative uptake was tested using acid copper chromate (ACC) preservative by a dipping process. The effect of radiation intensity and time on preservative uptake and air permeability were studied. The results revealed remarkable increase in longitudinal wood air permeability and preservative uptake with the increase of intensity and time of treatment. The results indicate that this technology can be tested and applied on pilot scale for application in wood preservation industry.

Chemical modification is used to efficiently improve some properties of wood to make it suitable for specific end uses. Modification using acetic anhydride (AA) is found suitable to make the wood more stable dimensionally. Pinus radiata wood samples treated with pyridine catalyzed AA were exposed to four different treatment methods comprising vacuum dipping and full cell method (cured with and without chemical). Physical properties like weight percentage gain (WPG), bulking coefficient, swelling coefficient (S) due to the chemical, water absorption and anti-swelling efficiency (ASE) were assessed for a comparative analysis. Results indicated a significant reduction in water absorption of acetylated wood. The swelling coefficients of all the treatments were found in the range of 3.86–4.96, which was twice to three times less than in the control (11.72) attributing 55–64% improvement in dimensional stability. Samples treated with full cell method and cured in the chemical mixture showed minimum swelling coefficient and best anti-swelling efficiency. All the four treatment methods chosen for the study returned significantly better dimensional stability as compared to untreated wood.

Wood is prone to fire attack making its application restricted as building material. The current study aims to evaluate the effect of double step chemical modification on Pinus radiata using Dimethyl Methyl phosphonate with Propylene oxide and Maleic anhydride. Wood samples were modified by single step using Propylene oxide (PO) or Maleic anhydride (MA) and the doublestep modification comprised firstly of pressure treatment with Dimethyl Methyl phosphonate (DMMP) followed by chemical modification using Propylene oxide (PD) or Maleic anhydride (MD). Thermal property was studied using Thermo Gravimetric Analysis (TGA) and Derivative Thermogravimetric (DTG). The chemical modification resulted in better thermal stability of wood than control wood. Among treatments PD showed best fire retardancy property with maximum weight loss at 367°C with 18.2% residual mass. The preliminary study indicates that double step modification improved the thermal property increasing the temperature for maximum weight loss and residual mass comprising of char.

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The effectiveness and integrity of forest-based emissions reduction schemes such as Clean Development Mechanism Afforestation Reforestation (CDM A R) project and Reducing Emissions from Deforestation and Degradation (REDD+), along with conservation and enhancement of carbon (C) stocks implementation and assessment in developing countries are required not only, the appropriate monitoring and evaluation, rather the precise values of constants being used to estimate the C stocks or C credit in place of default or guess value. Estimates are reported of the C content of wood of four forest species (Shorea robusta, Pinus roxburghii, Tectona grandis and Cinnamomum camphora) and two important farm species (Populus deltoides and Eucalyptus treticornis) in the temperate region of Indian Himalayas, derived using the ash content method. These species were considered keeping in view of their potentiality for the C sequestration and storage projects across the developing countries specifically the South East Asian Countries. The specific gravity, ash content and C proportion is estimated for these six species by selecting random woods pieces. These estimates are designed to improve the calculations of biomass C for use in estimation of C credits in the developing region under CDM A R projects and REDD+ program supported by developed country. Regression analysis of C prediction models revealed that, for all six species, C content may be estimated through specific gravity of the wood by a linear equation without intercept. Indirectly, this results also implies that among the two farm trees, eucalyptus has high potentiality for C capturing