Physical properties of black cottonwood and balsam poplar

1986 ◽  
Vol 16 (3) ◽  
pp. 491-496 ◽  
Author(s):  
R. M. Kellogg ◽  
E. P. Swan
Keyword(s):  
Specific Gravity ◽  
Fiber Length ◽  
Bending Strength ◽  
Tree Height ◽  
Strength Properties ◽  
Species Group ◽  
Core Material ◽  
Black Cottonwood ◽  
Balsam Poplar ◽  
Dimension Lumber

The objective of this study was to characterize selected properties of black cottonwood and balsam poplar to determine whether these species should be distinguished in their utilization. At present, black cottonwood is excluded from the "northern aspen" species group embraced by the National Lumber Grading Agency grading rules for dimension lumber and from use as core material in softwood plywood. Samples of black cottonwood were obtained from three sites in British Columbia. Samples of balsam poplar were obtained from three sites in Alberta. Ten tres were randomly selected from each site and a single 130 cm long bolt was collected immediately above breast height (1.36 m) from each tree. From two trees on each site, three additional bolts of the same length were collected immediately above the height positions located at 25, 50, and 75% of total tree height. The average basic specific gravity of the two species did not differ significantly (black cottonwood, 0.338; balsam poplar, 0.337) in this study. However, differences do exist between site averages, at least for black cottonwood. The initial green moisture contents differ significantly (black cottonwood, 160.5%; balsam poplar, 120.6%) and may be expected to affect their drying requirements differentially. For both species, the specific gravity increases and the green moisture content decreases with increasing height position in the tree. The average fiber length of black cottonwood is significantly longer than that of balsam poplar. The bending properties of strength and stiffness for black cottonwood were found to be significantly greater than for balsam poplar. Variation of these properties with height position in the tree was studied. Fiber length was found to decrease with increasing height position, while the bending strength properties were not affected by height position.

Chemical properties of black cottonwood and balsam poplar

1986 ◽  
Vol 16 (3) ◽  
pp. 497-501 ◽  
Author(s):  
E. P. Swan ◽  
R. M. Kellogg
Keyword(s):  
Lignin Content ◽  
Chemical Properties ◽  
Species Group ◽  
Core Material ◽  
Chemical Components ◽  
Extractive Content ◽  
Black Cottonwood ◽  
Balsam Poplar ◽  
Dimension Lumber ◽  
Fraser Valley

Taxonomically, black cottonwood and balsam poplar are varieties of the same species. However, black cottonwood is excluded from the "northern aspen" species group embraced by the National Lumber Grading Agency grading rules for dimension lumber and from the use as core material in softwood plywood. This study examines the chemical properties of these two species varieties to assess whether continuing differentiation in their utilization is justified. Black cottonwood was sampled at three sites in British Columbia (Fraser Valley, Squamish Valley, Kingcome Inlet) and balsam poplar was sampled at three sites in Alberta (Lodgepole, Slave Lake, Lac La Biche). Representative subsamples of wood and bark meal were prepared from each original sample. Black cottonwood and balsam poplar did not differ significantly in lignin content. Within each species, the heartwood had higher lignin contents than the sapwood. The mean extractive content of the female trees is higher than that of the male trees, but this was statistically significant for only the benzene–alcohol extractive content of the black cottonwood sapwood. The pH and acidity did not differ significantly between species. However, there was a large difference between heart-wood and sapwood pH values in both species; sufficient to provide a basis for their differentiation. Acidity values were higher for both sapwoods than for heartwoods. The chemical component contents of black cottonwood and balsam poplar bark were the same, except for the benzene–alcohol extractive content, which was twice as great in balsam poplar. However, the same chemical components were found in each extractive mixture. Results do not provide any basis for separate commercial utilization of these two varieties of the same species.

scholarly journals Variation Among Poplar (Populus Deltoides Bartr.) Clones for Growth, Wood Traits and Tolerance to Leaf Spot Diseases

2020 ◽  
Vol 8 (2) ◽  
pp. 128-136
Author(s):  
GPS Dhillon ◽  
Jajjbir Singh Sandhu ◽  
Parminder Singh
Keyword(s):  
Specific Gravity ◽  
Leaf Spot ◽  
Fiber Length ◽  
Populus Deltoides ◽  
Growth Traits ◽  
Tree Height ◽  
Clonal Variation ◽  
Leaf Spot Disease ◽  
Wood Traits ◽  
Collar Diameter

Poplar is economically important and fast growing tree species which is widely adopted by farmers of northwest India. The nursery study was conducted for two years to find out clonal variation for plant height, collar diameter, biomass, wood traits and incidence of leaf spot disease. Results found significant differences among the clones for all growth traits, specific gravity and fiber length. Clones L-290/84, 22-N and L-50/88 were promising for tree height and collar diameter during 1st year study. In 2nd year the tree height was highest in L-7/87 but was at par with L-34/82. L-7/87, L-247/84 and L-48/89 were promising for diameter. Clones L-48/89, L-7/87, 22-N, L-247/84, S7C8, and WSL-22 recorded superiority for both above ground and root biomass. The maximum fiber length was recorded in clone WSL-29 (0.936 mm) which was at par with those of WSL-22, L-17/92 and L-50/88. The wood specific gravity ranged from 0.383 to 0.498. Clone L-290/84 was at top rank but statistically par with 40-N, G-48, L-50/88 and T-90. The relative resistance for leaf spot was the higher in L-290/84, 40-N and WSL-29 in 1st year, and WSL-29, L-17/92, L-290/84, 22-N, 40-N, S7C8, and L-48/89 were found to be resistant during 2nd year. On the basis of all the traits clones L-48/89, 22-N, L-290/84, 40-N, and WSL-22 have shown promise and need to be tested at multiple sites before commercial cultivation.

scholarly journals Basic strength properties of beech wood in coppice forests G.J. "Crni Vrh - Kupinovo",

2004 ◽  
pp. 141-153
Author(s):  
Zdravko Popovic ◽  
Nebojsa Todorovic
Keyword(s):  
Bending Strength ◽  
Beech Wood ◽  
Tree Height ◽  
Strength Properties ◽  
Scientific Production ◽  
Management Unit ◽  
Production Experiment ◽  
Shock Resistance ◽  
Coppice Forest ◽  
Basic Strength

The basic mechanical properties of beech wood in coppice forest, locality Bor-Boljevac, Management unit "Crni Vrh-Kupinovo" were studied: Bending strength, modulus of elasticity in bending and shock resistance. Eight trees were taken from two series covered by the scientific-production experiment in this management unit. The statistically processed results were presented for each tree. There is a very strong correlation of the general linear form y=ax+b between the study properties, except between density and shock resistance. Static bending strength decreases mildly with tree height. The analysis shows that the average values of the study properties of beech wood at this locality are approximately the same as the values at other localities in the former SFRY. The only deviation is shock resistance.

Mechanical Grading of Structural Larch Dimension Lumber

2012 ◽  
Vol 517 ◽  
pp. 683-688 ◽  
Author(s):  
Wan Li Lou ◽  
Hai Qing Ren ◽  
Zhao Hui Wang ◽  
Xiu Qin Luo
Keyword(s):  
Modulus Of Elasticity ◽  
Bending Strength ◽  
Strength Properties ◽  
Modulus Of Rupture ◽  
Bending Test ◽  
Total Production ◽  
Good Relationship ◽  
Dimension Lumber ◽  
Structural Applications ◽  
Viable Approach

Larch dimension lumber bending strength properties from full-size bending test were used to establish preliminary grade boundary settings for mechanical grading of lumber by modulus of elasticity. Simulated production using the grade boundary settings were evaluated for modulus of rupture, ultimate tensile strength, and ultimate compressive strength. The results showed a good relationship between modulus of rupture and modulus of elasticity, and the observed relationships between strengths properties were consistent with that assumed for the standard grades. Through mechanical grading, larch dimension lumber could be sort grades: M14, M30 and M40. Assuming the visual requirements are met, the M30 and M40 grades account for more than 80% of the total production. Mechanical grading of larch appears to be a viable approach for grading Chinese large for structural applications.

scholarly journals Density, hardness and strength properties of densified fir and aspen woods pretreated with water repellents

Holzforschung ◽  
2020 ◽  
Vol 0 (0) ◽  
Author(s):  
Hüseyin Pelit ◽  
Fatih Emiroglu
Keyword(s):  
Compression Ratio ◽  
Bending Strength ◽  
Linseed Oil ◽  
Vacuum Treatment ◽  
Strength Properties ◽  
Aspen Wood ◽  
Positive Effect ◽  
Water Repellents ◽  
Impregnated Wood ◽  
Compression Temperature

AbstractIn this study, the effect of thermo-mechanical densification on the density, hardness, compression strength, bending strength (MOR), and modulus of elasticity (MOE) of fir and aspen wood pretreated with water repellents was analyzed. Wood specimens were impregnated with paraffin, linseed oil and styrene after pre-vacuum treatment. Then, the impregnated wood specimens were densified with compression ratios of 20 and 40%, and at 120, 150 and 180 °C. The results indicated that the density, hardness and strength properties of the all densified specimens (untreated and impregnated) increased depending on the compression ratio and temperature. For all tested properties, higher increases were obtained in the paraffin and styrene pretreated specimens compared to untreated samples. However, the increase rates in linseed oil pretreated specimens were generally lower than untreated specimens. Regarding water repellents the most successful results in all tested properties were determined in styrene pretreated specimens. The density, hardness and strength properties of all specimens increased with the increase in compression ratio. On the other hand, the increase in the compression temperature negatively affects the properties of untreated and linseed oil pretreated specimens, while having a generally positive effect on the properties of paraffin pretreated specimens. However, all tested properties of styrene pretreated specimens have increased significantly due to the increase in compression temperature. The increasing strength properties of wood as a result of densification have increased much more with paraffin and especially styrene pretreatment. These combinations can be considered as an important potential for applications that require more hardness and strength.

Study on Particleboard made from Nipa palm (Nypa fruticans) stem wood and Rajkoroi (Albizia richardiana) wood

2018 ◽  
Vol 25 (1) ◽  
pp. 15-18
Author(s):  
Md. Mahabubur Rahaman ◽  
◽  
Khurshid Akhter ◽  
S. Hossain ◽  
Md. Rakibul Islam ◽  
...  
Keyword(s):  
Tensile Strength ◽  
Dimensional Stability ◽  
Bending Strength ◽  
Strength Properties ◽  
Wood Chips ◽  
Standard Specification ◽  
Stem Wood ◽  
Nypa Fruticans ◽  
Albizia Richardiana ◽  
Nipa Palm

The study was conducted to find out the suitability of making particleboard using nipa palm (Nypa fruticans) stem wood and rajkoroi (Albizia richardiana) wood chips. Particleboards were fabricated at six different ratios of nipa palm stem and rajkoroi wood chips such as 100:0, 75:25, 50:50, 25:75, 10:90 and 0:100. Characteristics of particleboards such as modulus of rupture, internal bond strength, water absorption, thickness swelling and moisture content were measured. Results shows that particleboards made from 100% rajkoroi wood chips have the highest static bending properties and highest tensile strength properties of other particleboards but 100% nipa palm stem wood chips have the lowest static bending and lowest tensile strength properties of other particleboards. 10% nipa palm stem wood chips particleboard have the highest bending strength and tensile strength is better than 100% nipa palm stem wood chips and other mixing chips of particleboards. Mechanical, water resistance and dimensional stability properties were tested according to Indian standard specification. Tensile strength passed the British and German standard specification and nearest to Bureau of Indian Standard, bending strength was found nearest to Indian Standard but lower than German and British Standard specification. Strength property of rajkoroi wood chips particleboard is higher than nipa palm steam wood chips particleboard but dimensional stability is lower than nipa palm steam wood chips particleboard.

scholarly journals Fractional pulping of packaging board in high consistency drum pulping

TAPPI Journal ◽  
2017 ◽  
Vol 16 (02) ◽  
pp. 89-95
Author(s):  
HEIKKI UPOLA ◽  
ARI AMMALA ◽  
MIRJA ILLIKAINEN
Keyword(s):  
Energy Consumption ◽  
Energy Saving ◽  
Fiber Length ◽  
Short Fiber ◽  
Strength Properties ◽  
Ash Content ◽  
Packaging Materials ◽  
Wet Strength ◽  
Fiber Fractions ◽  
High Consistency

A wide variety of packaging materials with different wetting rates and wet strength properties are used in old corrugated container (OCC) processing. The disintegration rates of the different grades also vary and enable the use of the fractional pulping concept where easily disintegrated material is removed at the early stages. In the present study, fractional drum pulping was studied by pulping (Pilot drum pulping) and fractionating (Tampella oscillating screen) a mixture of strong-grade kraftliner and weak-grade fluting at high consistency to determine if energy consumption could be reduced. The results showed that a 25% energy saving could be realized through fractional pulping and an even higher potential might be possible if pulping conditions are optimized. Average fiber length, fines content, and ash content in the separated fractions were analyzed. The separated short fiber fractions and long fiber fractions could be individually processed, thus decreasing the volumes in the unit processes on the OCC line.

scholarly journals New technology for developing a lightweight refiner plate for hardwood kraft pulp fibers

BioResources ◽  
2020 ◽  
Vol 15 (4) ◽  
pp. 9128-9142
Author(s):  
Byeong-Geol Min ◽  
Ji-Young Lee ◽  
Chul-Hwan Kim ◽  
See-Han Park ◽  
Min-Seok Lee ◽  
...  
Keyword(s):  
Stainless Steel ◽  
Fiber Length ◽  
Kraft Pulp ◽  
New Technology ◽  
Strength Properties ◽  
Pulp Fibers ◽  
Low Intensity ◽  
Novel Technology ◽  
Draft Angle ◽  
Reducing Energy

Sand casting makes it difficult to manufacture a fine bar plate for low intensity refining. This study introduced a novel technology for manufacturing lightweight fine bar plates and compared the effects to traditional bar plates. The lightweight fine bar plate base was manufactured using a lightweight aluminum alloy and stainless-steel. Because the bars were inserted into the plate vertically without the draft angle, the stock throughput was improved by approximately 27% compared to the sand-casted bar plates. Additionally, the lightweight fine bar plate maximized internal and external fibrillation while minimizing fiber length loss. In conclusion, the lightweight fine bar plate was shown to be more effective in improving the strength properties of paper and reducing energy consumption.

scholarly journals Size Effect on Strength Properties of Chinese Larch Dimension Lumber

BioResources ◽  
2015 ◽  
Vol 10 (2) ◽  
Author(s):  
Haibin Zhou ◽  
Liuyang Han ◽  
Haiqing Ren ◽  
Jianxiong Lu
Keyword(s):  
Size Effect ◽  
Strength Properties ◽  
Dimension Lumber
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