Experimental Study on the Tensile Properties of Bamboo Related to its Distribution of Vascular Bundles

Considering bamboo as a 2-phase natural composite made up of vascular bundles (reinforcement or fiber) and matrixes (ground tissues) on the scale of micromechanics. By test of bamboo specimens and analysis of microscopic images of their cross sections, the distribution of vascular bundles along the axial and radial of bamboo culm were investigated. The relations between tensile properties of bamboo and its distribution of vascular bundles were studied. The results show that the vascular bundles are graded distributing along the radius of bamboo culm. The volume fraction of vascular bundles is larger near the outside, and attenuates rapidly to about 40 percent of that at the location away from outer side about 1/3 thickness of bamboo culm, and than slowly reduces to 0 near the inner side of culm. In axial direction, the volume fraction of vascular bundles in the bottom culm is smaller than that in the middle culm where the volume fraction is less variation, and reaches the largest value at the top culm. The tensile moduli and strength of bamboo are linearly related to the volume fraction of vascular bundles. The tensile moduli and the strength of vascular bundle are largely grater than that of matrix. The stiffness and the strength of bamboo are mainly offered by vascular bundles.

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Efficiently, accurately, intelligently dissecting bamboo: characteristic of vascular bundle in Phyllostachys

10.1101/2021.12.01.470805 ◽

2021 ◽

Author(s):

Haocheng Xu ◽

Ying Zhang ◽

Jiajun Wang ◽

Tuhua Zhong ◽

Xinxin Ma ◽

...

Keyword(s):

Cross Section ◽

Radial Distribution ◽

Vascular Bundle ◽

Fiber Volume Fraction ◽

Volume Fraction ◽

Width Ratio ◽

Vascular Bundles ◽

Fiber Volume ◽

Detection Model ◽

Gradient Change

AbstractA comprehensive understanding of vascular bundles is the key to elucidate the excellent intrinsic mechanical properties of bamboo. This research aims to investigate the gradient distribution of fiber volume fraction and the gradient changes in the shape of vascular bundles along the radial axis in Phyllostachys. We constructed a universal transfer-learning-based vascular bundle detection model with high precision of up to 96.97%, which can help to acquire the characteristics of vascular bundles quickly and accurately. The total number of vascular bundles, total fiber sheath area, the length, width and area of fiber sheath of individual vascular bundles within the entire cross-section were counted, and the results showed that these parameters had a strongly positive linear correlation with the outer circumference and wall thickness of bamboo culms, but the fiber volume fraction (around 25.5 %) and the length-to-width ratio of the vascular bundles (around 1.226) were relatively constant. Furthermore, we layered the cross section of bamboo according to the wall thickness finely and counted the characteristics of vascular bundle in each layer. The results showed that the radial distribution of fiber volume fraction decreased exponentially, the radial distribution of the length-to-width ratio of vascular bundle decreased quadratically, the radial distribution of the width of vascular bundle increased linearly. The trends of the gradient change in vascular bundle’s characteristics were found highly consistent among 29 bamboo species in Phyllostachys.One sentence summaryA universal vascular bundle detection model can efficiently dissect vascular bundles in Phyllostachys, and the radial gradient change of vascular bundles in cross-section are found highly consistent.

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3D Visualization of Bamboo Node’s Vascular Bundle

Forests ◽

10.3390/f12121799 ◽

2021 ◽

Vol 12 (12) ◽

pp. 1799

Author(s):

Shan Li ◽

Shumin Yang ◽

Lili Shang ◽

Xinge Liu ◽

Jianfeng Ma ◽

...

Keyword(s):

Vascular Bundle ◽

3D Visualization ◽

Three Dimensional ◽

Axial Direction ◽

Vascular Bundles ◽

Opposite Pattern ◽

Water Transportation ◽

Conducting Tissue ◽

3D Network ◽

3D Volume

The vascular bundle is an important structural unit that determines the growth and properties of bamboo. A high-resolution X-ray microtomography (μCT) was used to observe and reconstruct a three-dimensional (3D) morphometry model of the vascular bundle of the Qiongzhuea tumidinoda node due to its advantages of quick, nondestructive, and accurate testing of plant internal structure. The results showed that the morphology of vascular bundles varied significantly in the axial direction. In the cross-section, the number of axial vascular bundles reached a maximum at the lower end of the sheath scar, and the minimum of it was at the middle of the diaphragm. The frequency of axial vascular bundles decreased from the lower end of the node to the nodal ridge, and subsequently increased until the upper end of the bamboo node. The proportion of parenchyma, fibers, and conducting tissue was 65.7%, 30.5%, and 3.8%, respectively. The conducting tissues were intertwined to form a complex 3D network structure, with a connectivity of 94.77%. The conducting tissue with the largest volume accounted for 60.26% of the total volume of the conducting tissue. The 3D-distribution pattern of the conducting tissue of the node and that of the fibers were similar, but their thickness changed in the opposite pattern. This study revealed the 3D morphometry of the conducting tissue and fibers of the bamboo node, the reconstruction of the skeleton made the morphology more intuitive. Quantitative indicators such as the 3D volume, proportion, and connectivity of each type of tissue was obtained, the bamboo node was enlarged mainly caused by the particularly developed fibers. This work laid the foundation for a better understanding of the mechanical properties and water transportation of bamboo and revealed the mystery of bamboo node shedding of Q. tumidinoda.

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Variation in Tensile Properties of Single Vascular Bundles in Moso Bamboo

Forest Products Journal ◽

10.13073/fpj-d-21-00002 ◽

2021 ◽

Vol 71 (3) ◽

pp. 246-251

Author(s):

Lili Shang ◽

Xing'e Liu ◽

Zehui Jiang ◽

Genlin Tian ◽

Shumin Yang

Keyword(s):

Mechanical Properties ◽

Vascular Bundle ◽

Longitudinal Direction ◽

Functionally Graded ◽

Moso Bamboo ◽

Vascular Bundles ◽

Fibrous Sheath ◽

Bamboo Culm ◽

Functionally Graded Composite ◽

Bundle Structure

Abstract Moso bamboo (Phyllostachys edulis), an apt example of an anisotropic, functionally graded composite material, is the most important commercial bamboo species of China. This species has excellent mechanical properties due to its unique vascular bundle structure. This article examines the variation in mechanical properties of single vascular bundles with respect to their location within a bamboo culm. The mechanical exfoliation method was used to prepare the single vascular bundle. This study found that moso bamboo has superior stiffness and strength. Additionally, the variation in properties was large in the radial direction but minimal in longitudinal direction. The large variation in mechanical properties of vascular bundles can be ascribed to the synergistic effect of the fibrous sheath and parenchyma rather than to changes in fibrous sheath properties. This study provides a basis for the structure application for moso bamboo.

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BANANA LEAVES QUALITY OF Musa balbisiana Colla. AND Musa paradisiaca L. BASED ON ANATOMICAL STRUCTURE

KnE Life Sciences ◽

10.18502/kls.v2i1.174 ◽

2015 ◽

Vol 2 (1) ◽

pp. 361 ◽

Cited By ~ 1

Author(s):

Maryani _ ◽

Puput Pratiwi

Keyword(s):

Cross Sections ◽

Vascular Bundle ◽

Nutrient Content ◽

Anatomical Structure ◽

Vascular Bundles ◽

Musa Balbisiana ◽

Musa Paradisiaca ◽

Cell Layers ◽

Banana Leaves

Indonesia is the main centre of banana biodiversity. Banana is preferred because of its high nutrient content and economical value. Besides, banana leaves, particularly from “Klutuk” banana (Musa balbisiana Colla.) is also well-known used as traditional wrapper of cakes and foods. The objective of this research was to know and to compare the anatomical structure of Musa balbisiana Colla. and Musa paradisiaca L. leaves, and their anatomical characters as quality indication of banana leaves used as cakes and foods wrapper. Cross sections of banana leaves were prepared using free hand section and paraffin embedding methods. Leaf clearing method was used to prepare upper and lower epidermal tissue slides. Parameters used were the arrangement of cells/tissues, length and width of vascular bundles, mesophyll thickness, the thickness of schlerenchyma tissue, the number of laticiferous and tanin cells, and stomata indexs. The data were analyzed using Analysis of Variance (Anova) continued by Duncan test at level 5%. The results showed that the anatomical structure of M.balbisiana Colla. and M. paradisiaca L. leaves consisted of epidermis, hypodermis, mesophyll, and vascular bundles. The supporting tissues were composed of sclerenchyma located at upper and lower side of vascular bundle. The number of cell layers composing upper and lower hypodermis; stomata number, stomata index, the length and width of stomata; the thickness of vascular bundles; the thickness of layers composing adaxial and abaxial mesophyll; the thickness of schlerenchyma layers and width of schlerenchyma tissue at vascular bundle as well as laticiferous and tannin cell were found differently between M. balbisiana Colla. and M. paradisiaca L. The values of meshophyll thickness, length and width of vascular bundle, the thickness of schlerenchyma tissue, the number of laticiferous cells and the number of tanin cells were higher for M. paradisiaca L than in M. balbisiana Colla. The smaller the thickness of schlerenchyma layers and the width of schlerenchyma tissue at vascular bundle as well as the less number of laticiferous and tannin cells were assumed to be correlated with the good quality of M. balbisiana Colla leaves as foods and cakes wrapper. Keywords: anatomy, banana leaves, Musa balbisiana Colla., Musa paradisiaca L.

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ALCAN 2027 T3511

Alloy Digest ◽

10.31399/asm.ad.al0424 ◽

2009 ◽

Vol 58 (8) ◽

Keyword(s):

Corrosion Resistance ◽

Physical Properties ◽

Tensile Properties ◽

Cross Sections ◽

Damage Tolerance ◽

Heat Treating ◽

2024 Alloy ◽

Zr Alloy

Abstract Alcan 2027 is an Al-Cu-Mg-Mn-Zr alloy, developed to provide higher strength and damage tolerance than the incumbent 2024 alloy. Alcan 2027 T3511 possesses good damage tolerance. This datasheet covers Alcan 2027 T3511 in both thin and the heavier cross sections. This datasheet provides information on composition, physical properties, and tensile properties as well as fatigue. It also includes information on corrosion resistance as well as forming and heat treating. Filing Code: AL-424. Producer or source: Alcan Inc.

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An experimental study of the motion of ice past obstacles by the process of regelation

Journal of Glaciology ◽

10.1017/s0022143000030744 ◽

1976 ◽

Vol 17 (75) ◽

pp. 79-98 ◽

Cited By ~ 14

Author(s):

E. M. Morris

Keyword(s):

Thermal Conductivity ◽

Experimental Study ◽

Cross Sections ◽

Transition Point ◽

Water Layer ◽

Single Object ◽

Two Systems ◽

Basal Sliding

AbstractThe results of regelation experiments, in which a single object is pulled through ice, cannot be applied directly to the problem of basal sliding in glaciers because the two systems have different geometries. When the force applied to a single object is small, impurities trapped in the regelation water-layer around the object inhibit the regelation process. At larger forces, above the Drake-Shreve transition point, impurities are shed in a trace behind the object. However, when ice moves over a series of obstacles a trace may exist above and below the transition point. The regelation velocity below the transition point is not reduced by the effect of trapped impurities. In an experiment in which brass cylingerrs of various cross-sections rotate in ice, the ratio between the expected regelation velocity, calculated using the basal-sliding theory of Nye, and the measured regelation velocity is 8±2, both above and below the transition point. The same ratio has been obtained by other workers with wires of similar thermal conductivity above the transition point. Measurements of température differences indicate that supercooling cannot be the main source of the unexpectedly low regelation velocities above the transition point.

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Experimental study of the $ \gamma p \rightarrow K^{0}\Sigma^{+}$, $ \gamma n \rightarrow K^{0} \Lambda$, and $ \gamma n \rightarrow K^{0} \Sigma^{0}$ reactions at the Mainz Microtron

The European Physical Journal A ◽

10.1140/epja/i2019-12924-x ◽

2019 ◽

Vol 55 (11) ◽

Cited By ~ 1

Author(s):

C. S. Akondi ◽

K. Bantawa ◽

D. M. Manley ◽

S. Abt ◽

P. Achenbach ◽

...

Keyword(s):

Experimental Study ◽

Cross Sections ◽

Differential Cross ◽

Legendre Polynomials ◽

Neutral Kaon ◽

Experimental Results ◽

Differential Cross Sections ◽

Theoretical Predictions ◽

Photoproduction Reactions ◽

Insight Into

Abstract.This work measured $ \mathrm{d}\sigma/\mathrm{d}\Omega$dσ/dΩ for neutral kaon photoproduction reactions from threshold up to a c.m. energy of 1855MeV, focussing specifically on the $ \gamma p\rightarrow K^0\Sigma^+$γp→K0Σ+, $ \gamma n\rightarrow K^0\Lambda$γn→K0Λ, and $ \gamma n\rightarrow K^0 \Sigma^0$γn→K0Σ0 reactions. Our results for $ \gamma n\rightarrow K^0 \Sigma^0$γn→K0Σ0 are the first-ever measurements for that reaction. These data will provide insight into the properties of $ N^{\ast}$N* resonances and, in particular, will lead to an improved knowledge about those states that couple only weakly to the $ \pi N$πN channel. Integrated cross sections were extracted by fitting the differential cross sections for each reaction as a series of Legendre polynomials and our results are compared with prior experimental results and theoretical predictions.

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An effective thermal conductivity and thermomechanical homogenization scheme for a multiscale Nb3Sn filaments

Nanotechnology Reviews ◽

10.1515/ntrev-2021-0015 ◽

2021 ◽

Vol 10 (1) ◽

pp. 187-200

Author(s):

Xiaoyu Zhao ◽

Guannan Wang ◽

Qiang Chen ◽

Libin Duan ◽

Wenqiong Tu

Keyword(s):

Volume Fraction ◽

Material Design ◽

Axial Direction ◽

High Heat ◽

Thermomechanical Properties ◽

Homogenization Theory ◽

High Heat Flux ◽

Element Analysis ◽

Hierarchical Microstructure ◽

Thermal Conductivities

Abstract A comprehensive study of the multiscale homogenized thermal conductivities and thermomechanical properties is conducted towards the filament groups of European Advanced Superconductors (EAS) strand via the recently proposed Multiphysics Locally Exact Homogenization Theory (LEHT). The filament groups have a distinctive two-level hierarchical microstructure with a repeating pattern perpendicular to the axial direction of Nb3Sn filament. The Nb3Sn filaments are processed in a very high temperature between 600 and 700°C, while its operation temperature is extremely low, −269°C. Meanwhile, Nb3Sn may experience high heat flux due to low resistivity of Nb3Sn in the normal state. The intrinsic hierarchical microstructure of Nb3Sn filament groups and Multiphysics loading conditions make LEHT an ideal candidate to conduct the homogenized thermal conductivities and thermomechanical analysis. First, a comparison with a finite element analysis is conducted to validate effectiveness of Multiphysics LEHT and good agreement is obtained for the homogenized thermal conductivities and mechanical and thermal expansion properties. Then, the Multiphysics LEHT is applied to systematically investigate the effects of volume fraction and temperature on homogenized thermal conductivities and thermomechanical properties of Nb3Sn filaments at the microscale and mesoscale. Those homogenized properties provide a full picture for researchers or engineers to understand the Nb3Sn homogenized properties and will further facilitate the material design and application.

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Knockout of Auxin Response Factor SlARF4 Improves Tomato Resistance to Water Deficit

International Journal of Molecular Sciences ◽

10.3390/ijms22073347 ◽

2021 ◽

Vol 22 (7) ◽

pp. 3347

Author(s):

Mengyi Chen ◽

Xiaoyang Zhu ◽

Xiaojuan Liu ◽

Caiyu Wu ◽

Canye Yu ◽

...

Keyword(s):

Water Stress ◽

Water Deficit ◽

Vascular Bundle ◽

Plant Resistance ◽

Quantitative Polymerase Chain Reaction ◽

Photochemical Efficiency ◽

Differentially Expressed ◽

Vascular Bundles ◽

Aba Signaling ◽

Auxin Response

Auxin response factors (ARFs) play important roles in various plant physiological processes; however, knowledge of the exact role of ARFs in plant responses to water deficit is limited. In this study, SlARF4, a member of the ARF family, was functionally characterized under water deficit. Real-time fluorescence quantitative polymerase chain reaction (PCR) and β-glucuronidase (GUS) staining showed that water deficit and abscisic acid (ABA) treatment reduced the expression of SlARF4. SlARF4 was expressed in the vascular bundles and guard cells of tomato stomata. Loss of function of SlARF4 (arf4) by using Clustered Regularly Interspaced Short Palindromic Repeats/Cas 9 (CRISPR/Cas 9) technology enhanced plant resistance to water stress and rehydration ability. The arf4 mutant plants exhibited curly leaves and a thick stem. Malondialdehyde content was significantly lower in arf4 mutants than in wildtype plants under water stress; furthermore, arf4 mutants showed higher content of antioxidant substances, superoxide dismutase, actual photochemical efficiency of photosystem II (PSII), and catalase activities. Stomatal and vascular bundle morphology was changed in arf4 mutants. We identified 628 differentially expressed genes specifically expressed under water deficit in arf4 mutants; six of these genes, including ABA signaling pathway-related genes, were differentially expressed between the wildtype and arf4 mutants under water deficit and unlimited water supply. Auxin responsive element (AuxRE) elements were found in these genes’ promoters indicating that SlARF4 participates in ABA signaling pathways by regulating the expression of SlABI5/ABF and SCL3, thereby influencing stomatal morphology and vascular bundle development and ultimately improving plant resistance to water deficit.

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