Scanning Electron Microscopy (SEM) Energy Dispersive X-ray Spectroscopy (EDS) Mapping and In-situ Observation of Carbonization of Culms of Bambusa Multiplex.

Green culms of bamboo and charcoal of Bambusa multiplex were investigated by scanning electron microscopy (SEM) and energy dispersive X-ray spectroscopy (EDS) mapping. A dynamic observation of the initial stage of carbonization was also performed in-situ by heating a radial longitudinal section of the bamboo culm at a rate of 20°C/min up to 500°C. EDS mapping of the green bamboo culms detected Si signals in the harder cells such as the epidermis (Ep), cortex (Cor) and vascular bundle sheath (Bs) and between these cells as silicon oxide particles. Appreciable morphological change of the cells occurred in a temperature range of about 300-400°C due to the decomposition of cellulose that is the main component of the bamboo cells. The charcoal of the bamboo culm has a skin layer which originates from the Ep and Cor and the main central cylinder with many openings that originate from the expanded xylem and phloem holes. During carbonization, the Si atoms in the Ep and Cor were segregated as thin silicon oxide layers onto both the sides of the skin layer and the Si included in the Bs fibers and parenchyma cells accumulated near the walls of the openings.

Structural investigations on green culms and charcoal of Bambusa multiplex.

Green culms of Bambusa multiplex and the bamboo charcoal carbonized from the green culms at 700°C have been studied by means of X-ray diffraction, X-ray fluorescent element analysis, analytical scanning electron microscopy, and analytical scanning transmission electron microscopy (STEM), aiming at industrial applications as raw materials for functional devices and substances. It is revealed that the green culms and the charcoal contain a significant amount of Si, in particular, ∼18 wt % in the skin. The green culms comprise amorphous and crystalline celluloses. The charcoal has a so-called amorphous structure which is composed of randomly distributed carbon nanotubes and fibers. The growth of Ag-doped activated charcoal powders that were produced by two different methods using this charcoal powder has also been studied.

Structural observations and biomechanical measurements of clarinet reeds made from Arundo donax.

Plant anatomy was examined for two clarinet reeds made out of Arundo donax by different means of microscopy: light microscopy, low-energy secondary electron scanning electron microscopy (SEM), backscattered electron SEM, and helium ion microscopy (HiM). The local indentation hardness HIT and Young's modulus EIT of different tissues on their cross sections were measured. A vascular bundle (Vb) (HIT = 60-100 MPa, EIT = 1,500-2,000 MPa) that includes soft tissues of phloem and xylem and a vascular bundle sheath (Bs) (HIT = 300-500 MPa, EIT = ∼7,000 MPa) form a pipe of the strong string along the longitudinal direction of the cane. This Vb/Bs string is connected transversally with a net of thin cell-walls of parenchyma cells (Pa) (HIT = 70-200 MPa, EIT = 2,000-3,000 MPa) that also range along the longitudinal direction of the cane. It was turned out that the acoustic quality of a reed is mainly ascribed to the shape and configuration of Vb and the size of Pa. A reed where Vb bundles with continuous Bs rings are homogeneously distributed with higher proportion among a softer network of small Pa cells enables musical performance.

Structure and biomechanics of culms of Phragmites australis used for reeds of Japanese wind instrument "hichiriki".

Hichiriki is a traditional Japanese double-reed wind instrument used in Japanese ancient imperial court music, gagaku, which has been performed since the 7th century. The best reeds for hichiriki have been made of culms or stems of Phragmites australis (P. australis) that are harvested from only a limited reed bed at Udono near Kyoto. The aim of this study is to elucidate why the stems from Udono are the best materials for hichiriki reeds. Plant anatomy was examined for choice stems of P. australis grown in different reed beds in Japan as well as morphology, and the local indentation hardness and Young's modulus of tissues on the cross-sections of some representatives of hichiriki reeds were measured. It is concluded that the good stems for hichiriki reeds have an outer diameter of about 11 mm, a wall thickness of about 1 mm and comparatively homogeneous structure where harder materials, such as epidermis, hypodermis, sclerenchymatous cells, and vascular bundle sheaths with hard walls, are orderly deployed with softer materials such as parenchyma cells and vascular bundles. This structure has smaller differences of hardness and Young's modulus between the hard and soft materials in the reed, providing the best music performance.