Effect of growth ring angle on lateral enlargement of compressed Cryptomeria japonica wood impregnated with polyethylene glycol

Chikara Mizoguchi; Hiroki Sakagami; Noboru Fujimoto; Tetsuya Nakao

doi:10.15376/biores.15.4.8756-8769

Effect of growth ring angle on lateral enlargement of compressed Cryptomeria japonica wood impregnated with polyethylene glycol

BioResources ◽

10.15376/biores.15.4.8756-8769 ◽

2020 ◽

Vol 15 (4) ◽

pp. 8756-8769

Author(s):

Chikara Mizoguchi ◽

Hiroki Sakagami ◽

Noboru Fujimoto ◽

Tetsuya Nakao

Keyword(s):

Polyethylene Glycol ◽

Compression Ratio ◽

Cryptomeria Japonica ◽

Growth Ring ◽

Local Area ◽

Fiber Direction ◽

Ratio Curve ◽

Inflection Points ◽

Weak Negative Correlation ◽

Void Volumes

The lateral enlargement perpendicular to the compressive direction for small thin boards of Cryptomeria japonica was investigated to evaluate the effects of density and compressive directions to the radial (plane-sawn board) and 45 degrees of tilt to the radial (45º sawn board). Samples were impregnated with 200 and 20,000 molecular weight polyethylene glycol (PEG). The enlargement perpendicular to the fiber direction with deformation was obtained for heartwood and sapwood specimens treated only with PEG20,000. The compression ratio of specimens treated with PEG 20,000 exceeded the void volumes regardless of the wood density. Enlarged specimens of both sapwood and heartwood showed the inflection points in the force-compression ratio curve and no correlation between the compressive directions and lateral enlargement of specimens. In the local area showing the largest deformation, however, a weak positive correlation from plane-sawn boards and weak negative correlation from 45º sawn boards between the angles of compressive direction to growth ring and lateral enlargement were derived. Microfocus X-ray computer tomography in these areas showed the different morphological compressive deformations. The cells in the 45º sawn board were forced out due to each cell moving, whereas the radially arranged ones in the plane sawn board buckled under compression.

Download Full-text

Mosaic, block-face microscopy for measuring cell dimensions, cell collapse, and spatial relationships in wood

IAWA Journal ◽

10.1163/22941932-bja10072 ◽

2021 ◽

pp. 1-13

Author(s):

Alan Dickson

Keyword(s):

Growth Ring ◽

Local Area ◽

Intermediate Step ◽

Growth Rings ◽

Wall Area ◽

Sufficient Detail ◽

Cell Dimensions ◽

Block Face ◽

Wood Surfaces ◽

Cell Collapse

Abstract A conventional stereo light microscope was used to image polished wood surfaces at cellular resolution over size scales of the growth ring or larger. Bandpass filtering and local area contrast enhancement were used to aid automatic image thresholding and binarisation. An estimate for the location and proportion of cell collapse was introduced based on the distance between uncollapsed cell lumens. Additionally, spatial associations between vessels were determined using a Euclidean distance transform. The analysis of pith to bark cores provided sufficient detail to show significant intra and inter-annual trends in Pinus radiata tracheid dimensions (wall thickness, wall area, and radial widths). These trends were consistent with expectations and in agreement with the literature. Measured cell dimensions may be influenced by cell collapse and deformation as a result of drying. The analysis of air, kiln and oven-dried Eucalyptus nitens showed that cell collapse was highly variable but generally more prominent in the outer third of growth rings. There were significant changes in vessel shape across the growth rings and vessel area was significantly reduced by drying. The technique provides an intermediate step between detailed microscopy and macroscopic imaging that allows spatial analysis at the wood cell level.

Download Full-text

Full-field tracking and analysis of shrinkage strain during moisture content loss in wood

Holzforschung ◽

10.1515/hf-2020-0086 ◽

2020 ◽

Vol 0 (0) ◽

Author(s):

Zongying Fu ◽

Xiang Weng ◽

Yufa Gao ◽

Yongdong Zhou

Keyword(s):

Moisture Content ◽

Growth Ring ◽

Shrinkage Strain ◽

Tangential Direction ◽

Saturation Point ◽

Full Field ◽

Parabolic Distribution ◽

Ratio Curve ◽

Radial Shrinkage ◽

A Minor

AbstractAnisotropic shrinkage is a typically feature in wood, which is of critical importance in wood drying. In this study, the shrinkage strains over each growth ring were determined by a full-field strain measurement system during moisture content (MC) loss. Color maps were used to visualize the full-field distribution of displacement and shrinkage strain under different MC conditions. The variation of tangential and radial shrinkage strain from pith to bark, as well as the anisotropic shrinkage in heartwood and sapwood were studied. Both of the displacement and strain values increased as the MC decreased. From pith to bark, the tangential strains were higher at two poles as compared to the center, showing a parabolic distribution below fiber saturation point. While for radial shrinkage strain, a minor difference was observed except for the MC of 10%. An intersection between tangential and radial shrinkage ratio curve was observed at the MC of 28%. Both expansion and shrinkage in tangential direction were larger than radial counterparts, and the transformation from expansion to shrinkage occurred at the MC region of 32–28%. In addition, the shrinkage in heartwood was larger than sapwood, whereas anisotropic shrinkage in sapwood was more pronounced as compared to heartwood.

Download Full-text

Effects of Concentrical Partial (Local) Compression on the Structural Behavior of Concrete Filled Steel Tubular Column

Advances in Materials Science and Engineering ◽

10.1155/2015/491038 ◽

2015 ◽

Vol 2015 ◽

pp. 1-9 ◽

Cited By ~ 1

Author(s):

S. Jayaganesh ◽

J. Raja Murugadoss ◽

G. Ganesh Prabhu ◽

J. Jegan

Keyword(s):

Compression Ratio ◽

Local Area ◽

Structural Behavior ◽

Structural Performance ◽

Circular Section ◽

Experimental Parameters ◽

Section Type ◽

Cfst Columns ◽

Compression Area ◽

Stub Columns

The objective of this present paper is to investigate the structural behavior of square and circular Concrete Filled Steel Tubular (CFST) stub columns subjected to axial partial/local compression. The experimental parameters were local compression area and section type. Among the twelve specimens, six specimens were tested under full compression and the remaining six specimens were tested under local compression. The experimental observation indicated that the failure pattern of the CFST column with partial compression is fairly different from the CFST column subjected to full compression. The confinement provided by the circular section is quite different than the confinement provided by the square section, when the CFST column is subjected to axially local compression. It was found that the elastic modulus (stiffness) and the ultimate bearing capacity of the CFST column decreased with the increase in local compression ratio. The circular and square CFST columns subjected to partial/local compression achieved an ultimate strength of 4.45% and 14.15%, respectively, less than that of the columns subjected to full compression. From the above observation, it can be inferred that the structural performance of the CFST column is significantly influenced by the local area compression ratio and this effect should be taken into account in design models.

Download Full-text

A New Technique for the Demarcation Between Juvenile and Mature Wood in Cryptomeria Japonica

IAWA Journal ◽

10.1163/22941932-90001440 ◽

1996 ◽

Vol 17 (2) ◽

pp. 125-131 ◽

Cited By ~ 5

Author(s):

Chen Hui Lee ◽

Song Yung Wang

Keyword(s):

Cryptomeria Japonica ◽

Growth Ring ◽

Individual Growth ◽

Growth Rings ◽

Breast Height ◽

Disk Specimen ◽

Sample Tree ◽

Growth Increments ◽

A New Technique ◽

Central Taiwan

Three average, healthy Cryptomeria trees were felled in fall 1990 from a 40-year-old plantation located in central Taiwan. The plantation was established with l- year-old cuttings at a 2 × 2 m spacing. A5 cm thick circular-shaped disk specimen was removed from each sample tree at breast height, then a 2 em wide wood strip cut along the south-north aspect of each disk specimen. The wood strip was separated further into individual growth increments in odd-numbered growth rings numbered 1 (near pith) to 33 (near bark) and forty latewood tracheids per growth ring were measured. Their mean lengths were used as items in an analysis of variance on each of eight sets of data.

Download Full-text

Immunocytochemical detection of hepatic carbohydrate metabolic enzymes: Improved resolution with polyethylene glycol embedding and visio-bond semithin sections

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100124367 ◽

1992 ◽

Vol 50 (1) ◽

pp. 792-793

Author(s):

Kuixiong Gao ◽

Randal E. Morris ◽

Bruce F. Giffin ◽

Robert R. Cardell

Keyword(s):

Polyethylene Glycol ◽

Glycogen Phosphorylase ◽

Phosphoenolpyruvate Carboxykinase ◽

Glycogen Synthase ◽

Metabolic Enzymes ◽

Silver Stain ◽

Accurate Localization ◽

Immunocytochemical Detection ◽

Semithin Sections ◽

Parenchymal Cells

Several enzymes are involved in the regulation of anabolic and catabolic pathways of carbohydrate metabolism in liver parenchymal cells. The lobular distribution of glycogen synthase (GS), phosphoenolpyruvate carboxykinase (PEPCK) and glycogen phosphorylase (GP) was studied by immunocytochemistry using cryosections of normal fed and fasted rat liver. Since sections of tissue embedded in polyethylene glycol (PEG) show good morphological preservation and increased detectability for immunocytochemical localization of antigenic sites, and semithin sections of Visio-Bond (VB) embedded tissue provide higher resolution of cellular structure, we applied these techniques and immunogold-silver stain (IGSS) for a more accurate localization of hepatic carbohydrate metabolic enzymes.

Download Full-text

Directional observation on lipid of male nectary of Lindera megaphylla hemsl. by the rapid embedding method with polyethylene glycol (PEG)

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100161151 ◽

1990 ◽

Vol 48 (3) ◽

pp. 718-719

Author(s):

Dai Dalin ◽

Guo Jianmin

Keyword(s):

Electron Microscope ◽

Polyethylene Glycol ◽

Chemical Reaction ◽

Traditional Method ◽

Osmium Tetroxide ◽

Unsaturated Lipid ◽

Embedding Method ◽

Long Period ◽

New Methods

Lipid cytochemistry has not yet advanced far at the EM level. A major problem has been the loss of lipid during dehydration and embedding. Although the adoption of glutaraldehyde and osmium tetroxide accelerate the chemical reaction of lipid and osmium tetroxide can react on the double bouds of unsaturated lipid to from the osmium black, osmium tetroxide can be reduced in saturated lipid and subsequently some of unsaturated lipid are lost during dehydration. In order to reduce the loss of lipid by traditional method, some researchers adopted a few new methods, such as the change of embedding procedure and the adoption of new embedding media, to solve the problem. In a sense, these new methods are effective. They, however, usually require a long period of preparation. In this paper, we do research on the fiora nectary strucure of lauraceae by the rapid-embedding method wwith PEG under electron microscope and attempt to find a better method to solve the problem mentioned above.

Download Full-text