Water States in Yellow Poplar During Drying Studied by Time-Domain Nuclear Magnetic Resonance
Keywords:Water state, migration, NMR, relaxation time
AbstractThe time-domain nuclear magnetic resonance (NMR) technique can easily distinguish water states according to spin-spin relaxation time and can give more quantitative information on water in wood than any other method. In this study, water states in yellow poplar were investigated with a time-domain NMR technique. Water migration during drying was also analyzed. The results of this study show that yellow poplar has five components in water states (bound and free water) according to spin-spin relaxation time at moisture contents greater than 100%. The number of different water states decreased with decreasing moisture content. The longest spin-spin relaxation time was about 400 ms for free water, and the shortest was about 1 ms for bound water. With the NMR resonance technique, water states in yellow poplar drying are distinguished easily and migration from one water state to another can be analyzed quantitatively. This technique can benefit wood drying modeling and simulation.
Araujo CD, Mackay AL, Hailey JRT, Whittall KP (1992) Proton magnetic-resonance techniques for characterization of water in wood—Application to white spruce. Wood Sci Technol 26(2):101-113.nCasieri C, Senni L, Romagnoli M, Santamaria U, De Luca F (2004) Determination of moisture fraction in wood by mobile NMR device. J Magn Reson 171(2):364-372.nCox J, McDonald PJ, Gardiner PA (2010) A study of water exchange in wood by means of 2D NMR relaxation correlation and exchange. Holzforschung 64(2):259-266.nEngelund ET, Thygesen LG, Svensson S, Hill CAS (2013) A critical discussion of the physics of wood-water interactions. Wood Sci Technol 47:141-161.nHartley ID, Kamke FA, Peemoeller H (1994) Absolute moisture-content determination of aspen wood below the fiber saturation point using pulsed NMR. Holzforschung 48(6):474-479.nLabbe N, De Jeso BJ, Lartigue C, Daudé G, Pétraud M, Ratier M (2006) Time-domain H-1 NMR characterization of the liquid phase in greenwood. Holzforschung 60(3):265-270.nLi T-Q, Odberg L (1993) Determination of pore sizes in wood cellu1ose fibers by 2D and IH NMR. Nord Pu1p Pap Res J 3:326-330.nMenon RS, Mackay AL, Hailey JRT, Bloom M, Burgess AE, Swanson JS (1987) An NMR determination of the physiological water distribution in wood during drying. J Appl Polym Sci 33(4):1141-1155.nMerela M, Oven P, Sersa I, Mikac U (2009) A single point NMR method for an instantaneous determination of the moisture content of wood. Holzforschung 63(3):348-351.nNanassy AJ (1976) True dry-mass and moisture content of wood by NMR. Wood Sci 9(2):104-109.nSharp AR, Riggin MT, Kaiser R, Schneider MH (1978) Determination of moisture content of wood by pulsed nuclear magnetic resonance. Wood Fiber Sci 10(2):74-81.nSimpson WT, Skaar C (1968) Effect of transverse compressive stress on loss of wood moisture, FPL-0197. USDA For Serv Forest Prod Lab, Madison, WI. 9 pp.nSkaar C (1988) Wood-water relations. Springer-Verlag, Berlin, Germany, New York, NY. 292 pp.nThygesen LG (1996) PLS calibration of pulse NMR free induction decay for determining moisture content and basic density of softwood above fiber saturation. Holzforschung 50(5):434-436.nXu Y, Araujo CD, Mackay AL, Whittall KP (1996) Proton spin-lattice relaxation in wood—T-1 related to local specific gravity using a fast-exchange model. J Magn Reson B 110(1):55-64.nZhang M, Gazo R, Cassens D, Xie J (2006) Moisture distribution in a dried red oak lumber package stored in a high humidity environment. Forest Prod J 56(4):75-80.nZhang M, Gazo R, Cassens D, Xie J (2007) Water vapor adsorption in kiln dried red oak. Wood Fiber Sci 39(3):397-403.n
The copyright of an article published in Wood and Fiber Science is transferred to the Society of Wood Science and Technology (for U. S. Government employees: to the extent transferable), effective if and when the article is accepted for publication. This transfer grants the Society of Wood Science and Technology permission to republish all or any part of the article in any form, e.g., reprints for sale, microfiche, proceedings, etc. However, the authors reserve the following as set forth in the Copyright Law:
1. All proprietary rights other than copyright, such as patent rights.
2. The right to grant or refuse permission to third parties to republish all or part of the article or translations thereof. In the case of whole articles, such third parties must obtain Society of Wood Science and Technology written permission as well. However, the Society may grant rights with respect to Journal issues as a whole.
3. The right to use all or part of this article in future works of their own, such as lectures, press releases, reviews, text books, or reprint books.