| Plantation wood of Carya illinoinensis (Wangenn.) K.Koch was collected by the forestry science institute in Huangshan city. It was aimed at providing theoretical basis for the processing and utilization of wood and " three things left" by systematic research on this economic and material wood. This paper mainly studied anatomical properties, and used X-ray diffraction to determine the cellulose crystallinity. Meanwhile, according to the standard in wood industry, determined the main chemical properties (such as cellulose content, lignin content and hemicellulose content, etc) and the physical and mechanical properties(such as bending strength, compressive strength, etc), then analyzed the properties variation within and between strains. The results were as follows:(1)The variation range of fiber length of Carya illinoinensis (Wangenn.) K.Koch was from 716.62μm to 1579.71μm,the average was 1181.35 μm, the radial variation was significant. Tree-age was influential, radial variation presented a increasing tendency and then reduced. The same to variation axial,increased gradually upward from stem basis, maximum at 3.3m, then decreased gradually to the minimum at the site of the trees.(2)The variation range of fiber diameter of Carya illinoinensis (Wangenn.) K.Koch was from 711.56μm to 40.11μm, the average was 23.96μm. The variation range of fiber lumen diameter was from 4.06μm to 26.12μm, the average was 10.71 μm. The variation range of double wall thickness was from 4.57μm to 24.95μm, the average was 13.29μm. The radial variation was significant. Increased gradually outward from the pith on radial, flucated in a limited and certain extent. The variation trend on axial reduced first and then increased, maximum at 1.3m, reduced gradually to minimum at 3.3m then increased upward.(3)The variation range of fiber length-width ratio of Carya illinoinensis (Wangenn.)K.Koch was from 41.39 to 64.75, the average was 51.59, the radial variation was significant. Tree-age is influential, the radial variation trend is similar with the fiber diameter and fiber lumen diameter, increased first then reduced. The axial variation trend was opposite to the fiber diameter and fiber lumen diameter, increased first then reduced,but the numerical value was fluctuated slightly.(4)The variation range of fiber wall thickness-lumen ratio of Carya illinoiennsis (Wangenn.) K.Koch was from 0.54 to 0.7, the average was 0.63, the radial variation was significant. Tree-age was influential, the numerical value fluctuated in a certain extent on radial. But the fluctuation on axial was not obvious, difference was very small. (5)The variation range of fiber lumen-diameter ratio of Carya illinoinensis (Wangenn.) K.Koch was from 0.37 to 0.51, the average was 0.45, the radial variation was not significant. Tree-age was not influential, the numerical value fluctuated in a limited extent on radial. The height of tree was also not influential,fluctuation on axial vas not obvious (6)Proportion of ray was from 22.72% to 33.52%, the average was 27.77%.Proportion of vessel was from 10.72% to 17.04%, the average was 12.87%. Proportion of fiber was from 53.2% to 65.28%, the average is 59.37%, the radial variation of three proportions were all significant. Tree-age was influential on the radial, the proportion of ray increased first then reduced while the proportion of fiber reduced first then increased, meanwhile, the proportion of vessel fluctuated within a certain growth. But the height of tree was not influential, the numerical value of three proportions were fluctuated slightly.(7) The variation range of the wood ray height of Carya illinoinensis (Wangenn.) K.Koch was from 190.03μm to 271.78μm, the average was 227.56μm. The variation range of the wood ray width was from 16.51 μm to 28.48μm, the average is 22.06μm, the radial variation were significant. Tree-age was influential, the numerical value fluctuated within a certain growth on radial. The height of tree was also influential, reduced first then increased on axial. (8)The variation range of the air-dry density of Carya illinoinensis (Wangenn.) K.Koch was from 0.57g/cm3 to 0.76g/cm3, the average was 0.68g/cm3. The height of tree was influential, the axial variation trend was increased upward.(9)The variation range of bending strength of Carya illinoinensis (Wangenn.) K.Koch was from 76.6MPa to 95.83MPa, the average was 88.46MPa. The variation range of bending modulus of elasticity was from 7.77GPa to 9.6GPa, the average was 8.24GPa. The height of tree was influential, the axial variation trend was reduced upward.(10)The variation range of compressive strength parallel-to-grain of Carya illinoinensis (Wangenn.)K.Koch was from 34.2MPa to 47.7MPa, the average was 38.59MPa. The variation range of compressive strength perpendicular-to-grain was from 18.3MPa to 31.7MPa, the average was 24.58MPa. The height of tree was influential, the axial variation trend was increased first then reduced..(11)The benzene-alcohol extracts,1% NaOH extracts, klason lignin, holocellulose, a-cellulose, nitric acid-ethanol cellulose and ash mass fraction were 1.92%,16.14%,23.80%,82.77%,45.2%,48.83% and 0.74% respectively.(12)The variation trend of chemical components along axial direction among different samples kept consistent, whose benzene-alcohol extracts, ash, 1% NaOH extracts and lignin mass fraction increased progressively, while those of a-cellulose, nitric acid-ethanol cellulose, and holocellulose decreased progressively.(13)The variation range of cellulose crystallinity of Carya illinoinensis (Wangenn.) K.Koch was from 29.7% to 44.9%,the average is 38.64%. The axial variation trend kept consistent between trees. The cellulose crystallinity increased firstly and then declined. Meanwhile, the size of the order of cellulose crystallinity content was middle part, then stem base and lowest in tip.(14)According to the analysis on this paper, the fiber length of Carya illinoinensis(Wangenn.) K.Koch was large and the content is high, so the "three things left" can be used as excellent pulp and artificial board material. The mechanical properties of Carya illinoinensis(Wangenn.) K.Koch was general, may not be used as bearing or supporting materials in the building and furniture, but can be used as decoration, furniture material. |
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