Bamboo tests

In a similar five-cycle water-soaking/ovendrying test on bamboo particleboards, control boards swelled more than 30 percent, while boards made from acetylated particles swelled about 10 percent. 

Because of the recent rash of hurricanes like Katrina and tsunamis, we have become more aware of the need for protection against their violence. Geotextiles play a major role in this protection. Reinforced soil was used by Babylonians 3000 years ago in the construction of their pyramid-like tower, ziggurats. One of these famous towers, the Tower of Babel, collapsed. For thousands of years, the Chinese used wood, straw, and bamboo for soil reinforcement including the construction of the Great Wall. In fact, the Chinese symbol for civil engineering can be translated as earth and wood. The Dutch have made extensive use of natural fibrous materials in their age-old battle with the sea. The Romans employed wood and reed for foundation reinforcement. By the 1920s, cotton fabrics were tested as a... 

Ku, Y. C. Chiou, C. H. "Tests on Fiber Morphology and Chemical Composition of Important Bamboos in Taiwan" Taiwan Foresty Institute Taipei, Taiwan, 1966 p 1-7. 

In February 2006, Japan s Mitsubishi Motors announced that it is to use the biopolymer, polybutylene succinate (PBS), in the interior of its new mini-car launched next year. In conjunction with Aichi Industrial Technology Institute, it has developed a material that uses PBS combined with bamboo fibre. PBS is composed of succinic acid, which is derived from fermented corn or cane sugar, and 1,4-butanediol. Bamboo grows quickly and is seen by Mitsubishi as a sustainable resource. In lifecycle tests, the PBS-bamboo fibre composite achieves a 50% cut in carbon dioxide emissions compared with polypropylene. Volatile organic compound levels are also drastically reduced, by roughly 85%, over processed wood hardboards. 

This research showed that bamboo has high tensile, flexural, and straining capacities. The tests also indicated that the strength-to-weight ratios are excellent for tension, compression, and flexure in all types of bamboo (14). However, bamboo has three major weaknesses low modulus, low bond stress, and high water absorption which leads to decay. These weaknesses are the major reasons why bamboo is not used widely in todays modem construction field. Many researchers have attempted to reduce the water absorption potential by using paint (2,6),... 

Numerous factors contribute to the bamboo strength, such as type, size, age, storage conditions and duration, type of test and test procedures,... 

In order to evaluate the variation in the stress-strain characteristics for a given bamboo culm, a Pennsylvania bamboo was used for this study. All Pennsylvania bamboo was obtained in the vicinity of Lehigh University. The diameter of the bamboo culm varies from 0.5 to 2 in. (1.27-5.08 cm). The length is approximately 10 to 15 ft (3.04-4.56 m) and is classified as A tecta bamboo (10). Figure 5 shows the bamboo specimens used for the compression tests. Two strain gages were placed on the... 

Table I. Comparison of Pull Test Performance by Treated and by Nontreated Bamboo Specimens...

Construction applications for sulfur have also been tested. Interlocking bricks made predominantly of sulfur have been found to speed up construction, but have inherent fire hazards, which restrict their use. Concrete blocks impregnated with molten sulfur have shown a more than tenfold increase in compressive strength, from 5.9 to 83.9 MPa (megapascals 1 MPa = 10 N/m ), at the same time as an improvement in tensile strength from 1.3 MPa to 8.5 MPa, for a 13-15% sulfur content [7]. It also improves its chemical resistance. Sulfur-coated bamboo has been found to be an economical yet effective concrete reinforcing agent as a replacement for steel, in areas where bamboo occurs naturally. 

Metal tube, pipe or piece of bamboo closed at one end, 4 to 6 inches long and 1 inch inside diameter, or glass test tube of similar dimensions. 

Hokama et al. developed an enzyme immunoassay (EIA) that replaced the RIA. ° The procedure incorporated horseradish peroxidase coupled to the sheep anticiguatoxin, and was similar in efficacy to the earlier RIA, but less expensive and more practical. However, trying to further simplify the enzymatic procedure, Hokama incorporated a coating on the bamboo sticks used as test tools, so they can adsorb the toxins and then be mixed with reagents.This method was proved successful in separating toxic from nontoxic fish. 

However, instead of the idealized coaxial layers shown in Figure 13.10a, MWNT prepared by CCVD sometimes exhibit a bamboo-like structure, as that shown in Figure 13.10c (85). This type of MWNT has many more defects than either SWNT or DWNT, and as a result, their intrinsic properties are inferior to those of less defective carbon forms. Also, the variabUity of properties from mbe to mbe is much higher than those seen in SWNT, as demonstrated by direct tensile test measurements conducted in a TEM chamber with AFM capabUity on individual MWNT grown by CCVD (86). 

Various commercially available textiles claiming antimicrobial activity were examined (Table 1). Active ingredients of the treated antimicrobial textiles included silvo, quaternary ammonium salts (QACs) and triclosan. The textile substrates for the treated samples were polyester or a polyester/ cotton blend. Fibres claiming antimicrobial properties such as bamboo and soy were also tested. Relevant untreated fobrics were examined as control samples. 

Characteristics Test Bamboo Bamboo Bamboo Bamboo Bamboo ... 

The photogrq)h showing the test tubes containing nutrient broth in which the samples of 100% bamboo fibre material and 100% cotton material (which were exposed to actual surgical conditions) were immersed and inoculated with Staphylococcus aureus and incubated for 24 hrs at 37° C, is shown in Fig.8. 

It could be seen from Fig.8 that in the test tube with cotton material sample, the nutrient broth is turbid. But in the test tube with bamboo material immersitmthe nutrient broth is clear. The development of turbidity in the nutrient broth is a clear indication of bacterial growth. Staying clear after 24 hrs incubation, the bamboo material has proved its anti bacterial characteristic. 

Immunological detection of ciguatoxins and related polyethers has received particular attention compared to other marine toxins. The initial RIA and enzyme immunoassay employing a polyclonal sheep anti-ciguatoxin antibody revealed cross-reactivities between ciguatoxins and other polyether toxins, suggesting the need for monoclonal antibodies. The availability of monoclonal antibodies allowed for the development of stick enzyme immrmoassay methods and solid-phase immunobead techniques (known as the paddle test), which successfully recognized toxins attached to correction fluid-coated bamboo sticks or paddles previously exposed to toxic fish tissues. 

In a novel study, Zou et al. [49] reported nanoscale structural and mechanical characterization of the cell wall of bamboo fibres. They reported the discovery of cobble-like polygonal cellulose nanograins with a diameter of 21-198 nm in the cell wall of bamboo fibres. These nanograins are basic building blocks that are used to construct individual bamboo fibres. Nanoscale mechanical tests were carried out on individual fibre cell walls by nanoindentation. It was found that the nanograin structured bamboo fibres are not brittle in nature but somewhat ductile. Figure 1.17a... 

It can be seen that the diameters vary from 0.3 to 0.9 mm for bamboo, from 0.1 to 0.8 mm for coir, from 30 to 150 pm for curaua, from 0.04 to 0.18 mm for jute, from 0.20 to 2.45 mm for piassava, from 0.019 to 0.209 mm for ramie, and from 0.04—0.22 mm for sisal fibers. Their mean diameters were found to be 0.56 mm, 0.28 mm, 90 pm, 0.082 mm, 1.00 mm, 0.114 mm, and 0.17 mm, respectively. Based on these, several diameter intervals for each fiber were considered, ranging from 5 to 12 intervals, depending on the fiber. Then, about 20 fibers from each interval were tested for fracture strength. 

Qian et al. conducted a study on bamboo particles (BP) that were treated with low-concentrations of alkali solution for various times and used as reinforcements in PLA based composites [35]. Characteristics of BP by composition analysis, scaiming electron microscopy, Brunauer-Emmett Teller test, and Fourier transform infrared spectroscopy, showed that low-concentration alkali treatment had a significant influence on the microstructure, specific surface area, and chemical groups of BP. PLA/treated-BP and PLA/untreated-BP composites were both produced with 30 wt% BP content. Mechanical measurements showed that tensile strength, tensile modulus, and elongation at break of PLA/BP composites increased when the alkali treatment time reached... 

H. Ismail, M. Edyhan, and B. Wirjosentono, Bamboo fibre filled natural rubber composites the effects of filler loading and bonding agent. Polym. Test. 21(2), 139-144 (2002). 

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