In order to clarify the bending properties of the laminated clothes having regularly different bending rigidities, such as the padded clothes or the quilting coats, a non-uniform beam model whose bending rigidity is variant along the direction of the length is supposed. On the basis of the model an analytical method on the bending behaviour is considered. It was proved that the analytical method using “Area-moment method” was effective for describing the bending of the laminated clothes with the ease in calculating with a micro computer. By this method, if the distribution of bending rigidity and weight in a laminated cloth is previously known, it is possible to obtain the correct deflection curve. Furthermore, referring to the deflection curve of the laminated cloth, the partially unknown bending rigidity can be calculated.
The effect of hoop winding on tensile and compressive properties of glass fiber reinforced plastic (GFRP)-filament winding (FW) pipes has been investigated experimentally. Winding angles of the helical filaments in FW pipes were ±20°, ±30°, ±45°, and ±60°. Both in tensile and compressive tests, specimens with the same shape and size were used. As for the specimen with hoop winding, Young's moduli on tension and compression are nearly equal. But the breaking strengths of the specimens with winding angle of ±20° and ±30° are considerably larger on tension than on compression, because of the difference of the failure modes: On tension, tensile breakage of fibers (+θ) and shear slippage between fibers (-θ) are observed simultaneously. While on compression, the fibers (±θ) are buckled and broken by bending. The effects of adding the hoop winding (winding angle_??_90°) to the GFRP-FW pipe are as follows: (1) On tension, Young's modulus and Poisson's ratio decrease and breaking strength increases. (2) On compression, Young's modulus and breaking strength increase remarkably. (3) The pantographic deformation observed on tensile test of the ±45° specimen without hoop winding is restricted. (4) The helical propagation of cracks observed on compression of the specimen without hoop winding is arrested by adding the hoop winding.
The structure characteristics of silk plain fabrics were studied by means of high speed scanning microscopy (E. D. P.) pattern and the contact printing image. The results obtained are summarized as follows. 1. The areas of the openings in the fabrics were 11-12% (gray), 3% (habutae) and 2% (crape). The shapes of the openings were: habutae and gray fabrics, in slit form with symmetry in respect to the perpendicular axis, and crape, in fusi- or triangle form with unsymmetry in respect to the perpendicular axis. 2. E. D. P. patterns were observed as checked patterns which differed depending on the warp shifting up and down at the intersection of warp and filling lines. 3. Judging from the optical properties, the fine structures of the silk plain fabrics were figured in detail in the fraunhofer diffraction patterns of the contact printing images. 4. In the fraunhofer pattern of E. D. P. pattern, the diffusion around the interference points are observed as equivalent density outlines. 5. Fraunhofer patterns of the silk plain fabrics contain exact informations of the area, number, form, size and position of the opening.
Adsorptions of 1, 2-ethane disulfonic acid (EDSA), 1, 4-butane disulfonic acid (BDSA) and sulfuric acid as the model compounds of dibasic dyes on polyamide were studied by NMR, the adsorption experiment and the flow type microcalorimetry. The results obtained are as follows: (1) The adsorption isotherms of alkyldisulfonic acids and sulfuric acid on polyamide were the Langmuir type. (2) Only one of the two sulfonic acid groups in alkyldisulfonic acids seemed to take part in adsorption. (3) -Δμ°I is of alkyldisulfonic acids were larger than that of the corresponding alkylmonosulfonic acids, because of the larger -ΔH°C•θ=1 and ΔS°C•I. (4) ΔS°C•I and |Δδ| of BDSA were larger than those of EDSA. These are due to the larger contribution of the hydrophorbic hydration in the former. (5) ΔS°C•I was positive and decreased with temperature in all cases.