scholarly journals Compression Properties of Small Clear Southern Yellow Pine Specimens Tested across Five Decades

2021 ◽  
Vol 71 (3) ◽  
pp. 240-245
Author(s):  
Rubin Shmulsky ◽  
Frederico José Nistal França ◽  
J. Tedrick Ratcliff ◽  
Benjamin Farber ◽  
C. Adam Senalik ◽  
...  
Keyword(s):  
Specific Gravity ◽  
Moisture Content ◽  
Wood Properties ◽  
Strength Properties ◽  
Raw Material ◽  
Clear Wood ◽  
Compression Properties ◽  
Three Samples ◽  
Yellow Pine ◽  
Southern Yellow Pine

Abstract Southern yellow pine (SYP) is one of the most used softwood species in the world. Most of this raw material come from fast-grown plantation trees. It is of interest to determine if SYP clear wood properties may have changed over the long term, in particular whether such properties may have declined. Herein, specific gravity (SG), ultimate compression strength parallel to grain (UCS‖), and UCS perpendicular to grain (UCS⊥) from three samples were compared: Sample 1 tested in 2014; Sample 2 from molding and millwork producers tested in 2017–2019; and Sample 3 from a study conducted in the mid-1960s. With respect to specific gravity (SG), the wood in Sample 1 was significantly lower than that from Samples 2 and 3. With respect to UCS‖, all three samples were statistically different. Adjusting to 12 percent moisture content had no influence on the mean separation of UCS‖. With respect to UCS⊥, no statistically significant differences were detected among the test data from any of the three samples. However, for the UCS data generated from the SG and moisture content–related model, Sample 2 was higher than Sample 3, and Sample 3 was higher than Sample 1, and these differences were statistically significant. Overall, these findings do not suggest that broad or consistent changes or declines of these wood strength properties have occurred during the past five decades.

scholarly journals Performance of Oriented Strand Board Made with Soy Substituted Resin in Termite Choice Tests with Southern Yellow Pine

2021 ◽  
Vol 71 (3) ◽  
pp. 199-208
Author(s):  
Qingzheng Cheng ◽  
Juliet D. Tang ◽  
Chengfeng Zhou ◽  
Wei Jiang ◽  
Lixia Hu ◽  
...  
Keyword(s):  
Weight Loss ◽  
Moisture Content ◽  
Oriented Strand Board ◽  
Soy Flour ◽  
Water Repellent ◽  
Rating Data ◽  
Structural Applications ◽  
Choice Tests ◽  
Yellow Pine ◽  
Southern Yellow Pine

Abstract Soy flour was evaluated as a partial substitute for resin in the manufacture of oriented strand board (OSB), a wood-based composite that often replaces solid lumber and plywood in structural applications in the construction industry. Since the presence of soy could alter OSB biodegradation properties, termite resistance of OSB panels made with 0, 10, and 20 percent of polymeric methylene diphenyl diisocyanate (pMDI) resin substituted with soy flour (OSB0, OSB10, and OSB20, respectively) was investigated. Single choice tests between three types of OSB and southern yellow pine (SYP) solid wood and an OSB choice test (OSB0 vs. OSB10) were evaluated. Results indicated that termites always showed a preference for SYP, with the OSB becoming less palatable when soy flour was present. Percentage weight losses for OSB0, OSB10, and OSB20 were 5.7×, 8.4×, and 8.6× less, respectively, compared with SYP. In the absence of SYP, termites did not differentiate OSB0 from OSB10, with OSB10 showing 1.5× less weight loss compared with OSB0. Visual rating data supported weight loss data, except significantly less damage was only found when the choice paired SYP with OSB made with soy (OSB10 or OSB20). Termite consumption preference for SYP was explained by differences in water absorption kinetics. SYP reached saturation (105% moisture content) within 1 week on moist sand, while moisture content of OSB composites slowly climbed to 79 percent over 4 weeks, never reaching a plateau. Lower moisture content was due to the presence of water-repellent resin and wax in the OSB.

Technological Properties of Wood from Trees in Polluted Regions

IAWA Journal ◽  
1986 ◽  
Vol 7 (4) ◽  
pp. 389-397 ◽  
Author(s):  
A. Frühwald
Keyword(s):  
Moisture Content ◽  
Wood Quality ◽  
Wood Properties ◽  
Biological Indicators ◽  
Strength Properties ◽  
West Germany ◽  
Technological Properties ◽  
Growth Rings ◽  
Physical Chemical ◽  
Faster Development

Wood quality from about 230 healthy and diseased fir, spruce, pine and beech trees from various locations in West Germany was tested. In general results are satisfactory for mechanical wood properties, but some physical, chemical and biological indicators lead to the conclusion that logs from heavily diseased trees may be attacked a !ittle earlier and faster by microorganisms during storage. Width of growth rings is reduced in severely damaged softwood trees on most locations whereas beech shows no significant reduction. Declining health of the trees had no or little influence on wood density; the modulus of elasticity and strength were at normal levels and independent of tree damage. Width and moisture content of sapwood were reduced little in pines but more in spruce and fir. A tendency to a more intensely developed irregular brown heartwood in severeIy damaged beech trees could not be proved until now. Storage of spruce in a log yard for four months has shown a slightly faster development of discoloration caused by fungi in diseased trees whereas after seven months wood from healthy trees was more discoloured. After storage strength properties are not or only slightly reduced, but no difference was found between trees assigned to the various health classes. After two years of storage under sprinkling water, pine logs from healthy and diseased trees show no difference in discoloration.

scholarly journals SIFAT FISIK BATANG DAN CABANG KAYU MAKADAMIA

PERENNIAL ◽  
2006 ◽  
Vol 2 (1) ◽  
pp. 16
Author(s):  
Andi Detti Yunianti
Keyword(s):  
Specific Gravity ◽  
Moisture Content ◽  
Physical Properties ◽  
Quality Indicators ◽  
Basic Density ◽  
Raw Material ◽  
Longitudinal Shrinkage ◽  
Wood Production ◽  
Efficient Utilization ◽  
Tangential Shrinkage

Since there have been a big difference between wood production and industrial need, wood diversification plays an important role in handling wood deficiencies. Wood raw material diversification could developed and increased throughout the use of whole parts of the tree including branch. The current study was aimed at understanding stem and branch physical properties (basic density, air-dry specific gravity, air-dry moisture content and shrinkage) of macadamia wood as quality indicators for efficient utilization in the future. For the purpose of the study, parts of stem and branch of the tree were taken from a macadamia tree. Test specimens of stem were cut 50 cm from the ground while that of branch were selected from the largest diameter at 10 cm distance from the main stem of the tree. All samples were tested for their physical properties according to ISO standards, 1975. Results showed that the basic density, air dry specific gravity and longitudinal shrinkage of the branchwood of macadamia were higher than those of the stem. The air-dry moisture content, radial and tangential shrinkage were low on the branchwood. Keywords : Wood Physical Properties, Branchwood , Macadamia Wood

Raw Material Quality of Short-Rotation, Intensively Cultured Populus Clones. II. Wood and Bark from First-Rotation Stems and Stems Grown from Coppice

IAWA Journal ◽  
1987 ◽  
Vol 8 (2) ◽  
pp. 182-186
Author(s):  
J.E. Phelps ◽  
J.G. Isebrands ◽  
R.M. Teclaw
Keyword(s):  
Specific Gravity ◽  
Fibre Length ◽  
Wood Properties ◽  
Raw Material ◽  
Short Rotation ◽  
Growth System ◽  
Basal Portion ◽  
Dormant Season ◽  
Hybrid Clones

The coppicing ability of Populus hybrid clones after dormant season harvesting is weil suited to a short-rotation, intensively cultured (SRIC) growth system. stems formed from coppice exhibit a greater amount of growth than first-rotation trees during the juvenile stage. This research examines and compares properties, including specific gravity and fibre length of the wood and bark, of 3-year-old firstrotation stems (from cuttings) and 3-year-old coppiced stems of three hybrid Populus clones grown und er SRIC. Trees produced from coppiced stumps were 1.5 to 2.5 times larger (in height and diameter at the base) than first-rotation trees after 3 years of growth. Some of the wood properties of the first-rotation trees differed from those of the coppiced trees. For example, wood specific gravity was higher and wood fibres were longer in the sampies removed from the basal portion of the first-rotation trees. Although significant, these differences were small and not important from an industrial standpoint. The increase in woody biom ass after coppicing is likely to be more important to industry than any decreases in wood properties expected during short-rotation, intensive culture of Populus trees.

Recommended moisture adjustment factors for lumber stresses

1982 ◽  
Vol 9 (4) ◽  
pp. 602-610 ◽  
Author(s):  
Borg Madsen
Keyword(s):  
Moisture Content ◽  
Strength Properties ◽  
Bending Stiffness ◽  
Clear Wood ◽  
Full Size ◽  
Allowable Stresses ◽  
Adjustment Factors ◽  
Effect Of Moisture

The present allowable stresses for lumber and the associated adjustment factors stated in Canadian Standard CSA-086 are based upon tests conducted using small clear wood specimens. Recent comprehensive tests in which full-size lumber specimens were used (in-grade testing) showed that the present allowable stresses cannot be confirmed and also that new adjustment factors need to be developed.This paper deals with the effect of moisture content on the strength properties. Tests were conducted and reported dealing with: bending, stiffness, tension, compression parallel to grain, compression perpendicular to grain, and shear. From these tests it was possible to make specific recommendations for a new set of moisture content adjustment factors, to be used in design, that more realistically reflect the behaviour of lumber.

Identification of representative sampling heights for specific gravity and moisture content in plantation-grown loblolly pine (Pinus taeda)

2012 ◽  
Vol 42 (3) ◽  
pp. 574-584 ◽  
Author(s):  
Finto Antony ◽  
Laurence R. Schimleck ◽  
Richard F. Daniels
Keyword(s):  
Specific Gravity ◽  
Moisture Content ◽  
Pinus Taeda ◽  
Loblolly Pine ◽  
Wood Properties ◽  
Representative Sampling ◽  
Breast Height ◽  
Sampling Height ◽  
Pinus Taeda L ◽  
Whole Tree

Conventionally, increment cores collected at breast height (1.4 m) have been used to measure wood properties of standing loblolly pine (Pinus taeda L.) trees. This height has been used because of the ease of sampling and cost involved in extracting the cores. In this study, the efficacy of a breast-height core to represent whole-tree specific gravity (SG) and moisture content (MC) was examined. The sampling height that best represents whole-tree SG and MC was identified using the correlation between volume-weighted whole-tree SG and MC with SG and MC measurements collected at different heights within a tree. We found a high correlation between observed whole-disk SG and MC with volume-weighted whole-tree SG and MC at most sampling heights. The strength of the correlation followed a skewed parabolic curve form for both wood properties. The strongest correlations were observed between 4.6 and 6.1 m, with marginally lower correlations at the base of the tree, and the weakest correlations were observed towards the tip of the tree. In addition, it was found that the number of stands and trees that need to be sampled to achieve a certain accuracy in overall mean whole-tree SG and MC was greater if breast height was used as a sampling height compared with the most representative sampling heights identified (4.6 m for SG and 6.1 m for MC).

Moisture adsorption characteristics of copper-ethanolamine (Cu-EA) treated Southern yellow pine (Pinus spp.)

Holzforschung ◽  
2004 ◽  
Vol 58 (1) ◽  
pp. 32-38 ◽  
Author(s):  
J. Cao ◽  
D. P. Kamdem
Keyword(s):  
Water Vapor ◽  
Relative Humidity ◽  
Moisture Content ◽  
Treated Wood ◽  
Untreated Wood ◽  
Moisture Adsorption ◽  
Adsorption Sites ◽  
Yellow Pine ◽  
Pinus Spp ◽  
Southern Yellow Pine

Abstract Moisture adsorption isotherms were determined for untreated and copper-ethanolamine (Cu-EA) treated wood at different copper retention levels. The Cu-EA treatment reduces the water vapor accessibility in wood because copper has occupied some of the adsorption sites for moisture during the treatment. The percentage of adsorption sites occupied by copper was evaluated by M t/M u, which is the ratio of equilibrium moisture content for treated wood to untreated wood. The results show that, within the copper retention range used in this study, the M t/M u value decreases linearly at lower temperatures (4 and 15 °C) or logarithmically at higher temperatures (30 and 40 °C) with the increase of copper retention, suggesting that the percentage of adsorption sites occupied by copper (P) increases linearly or logarithmically with the copper retention in Cu-EA treated wood. P decreases with the increase of relative humidity. The reason is that more adsorption sites become available for moisture at higher relative humidity. It has also been found that the influence of Cu-EA treatment on hydrated water (M h) is more significant than that on dissolved water (M s).

Interrelationships of specific gravity, stiffness, and strength of yellow pine across five decades

BioResources ◽  
2021 ◽  
Vol 16 (2) ◽  
pp. 3815-3826
Author(s):  
Frederico Jose Nistal França ◽  
Rubin Shmulsky ◽  
Tedrick Ratcliff ◽  
Benjamin Farber ◽  
C. Adam Senalik ◽  
...  
Keyword(s):  
Specific Gravity ◽  
Modulus Of Rupture ◽  
Resource Monitoring ◽  
Non Destructive Evaluation ◽  
Three Samples ◽  
Yellow Pine ◽  
The Relationship ◽  
Non Destructive ◽  
Insight Into ◽  
Over Time

The interrelationships among specific gravity (SG), modulus of elasticity (MOE), and strength (modulus of rupture, MOR) are largely the foundational basis for non-destructive evaluation and testing. Resource monitoring and commercial structural lumber production often rely upon such non-destructive evaluation to predict the bending and/or tension strength of individual members. These technologies require routine calibration. In addition, it is important to know the extent to which a given resource may change over time. To that end, this study investigated the relationship among SG, MOE, and MOR of small clear specimens from three samples taken across an approximate 50-year period; 1965 to 2018. Coefficients of determination among these variables are presented along with the prediction equations. These findings can be used to gain insight into the reliability and stability of these relationships over time.

scholarly journals Potensi Tiga Jenis Kayu Tanah Gambut Sumatera sebagai Bahan Baku Pulp dan Kertas (The Potential of Three Peat Land Woods of Sumatera as Pulp and Paper Raw Material)

2021 ◽  
Vol 17 (2) ◽  
pp. 112-121
Author(s):  
Kanti D Rizqiani ◽  
Yeni Aprianis ◽  
Ahmad Junaedi
Keyword(s):  
Specific Gravity ◽  
Exotic Species ◽  
Wood Species ◽  
Government Regulation ◽  
Fiber Quality ◽  
Wood Properties ◽  
Pulp And Paper ◽  
Raw Material ◽  
Pulp Wood

The growth of pulp and paper industries has encouraged the expansion of the industrial plantation forests for pulp wood. The  exotic species planted for pulp wood initially maintained a relatively high productivity, however it decreases in the following rotation cycles.  The peat land wood species of Sumatera could be an alternative for exotic species. However, the insufficient information on the wood properties has brought about they are less considered. This paper examined the fiber quality of Sumatran local peat-wood and its possibility as a raw material of pulp and paper. For specific gravity, samples were selected based on three different diameter groups in each plot. Fiber properties (dimension and fiber derivative values) used to asses the suitability of the wood for pulp and paper raw material were determined in accordance with the method of the Forest Product Laboratory (FPL). The resulted data and information were compared to those of krasikarpa (Acacia crassicarpa Benth.). The results showed that the fiber quality of sekubung wood was classified into grade II, while gerunggang and mahang putih were classified into grade III. The specific gravity of gerunggang wood was higher than these of other woods and comparable to that of krasikarpa. Although the growth of Sumatran local peat-wood is still low, however, conformity with government regulations (Government Regulation Number 57-2016 and Ministry of Environment and Forestry Regulation Number 17-2017) and fiber quality, the local peat-wood could potentially substitute the exotic wood species.

scholarly journals PHARMACEUTICO-ANALYTICAL STUDY OF SHODHITA SHILAJATU

2020 ◽  
pp. 1-6
Author(s):  
K. A. Patil ◽  
Satish G Patil ◽  
R S Sarashetti
Keyword(s):  
Specific Gravity ◽  
Moisture Content ◽  
Analytical Study ◽  
Normal Limit ◽  
Raw Materials ◽  
Raw Material ◽  
Physical Constants ◽  
Ancient Time

In the Pharmaceutical process of different forms of medicines raw material & its quality plays an important role. During ancient time Vaidyas were themselves used to collect the raw materials herbs based on their occurrence and organoleptic characters, i.e., typical taste, texture, smell, color, and there types after selection they utilized them in preparing medicines. Based on their own observations, principles of drug processing and ideal quality of finished product, etc., have been documented by them. The principles were developed based upon the scientific parameters prevailing in those days. Materials and Method: Raw Shilajatu was subjected to Shodhana and Shodhita shilajatu was subjected to analytical study. The required materials for the process were collected from the Pharmacy of BLDEA's AVS Ayurveda Mahavidyalaya pharmacy Vijayapur, analytical lab. Raw drugs were purchased from Dorle and Sons retailer from Kolhapur Maharashtra. Shilajatu shodhana was carried out according to reference mentioned in Rasaratna samuchaya. Analytical tests concern Indian Pharmacopeia methods were followed. Result: Raw Shilajatu took 5 ½ hour to 6hour in Shodhan procedure in both batches. Three days for drying. In analytical tests physical constants like pH ash value, solubility, specific gravity, moisture content etc result values were under normal limit.

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