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This paper presents the design and manufacturing process of a carbon fibre composite bicycle crank by using the compressionmoulding (CM) technology. Bulk moulding compound (B.M.C.)was manufactured by mixing strands (>1”) of chopped carbon fibres in a mixer with polyester resin. The crank body is treated as a composite sandwichstructure, where the interior is a short fibre layer (B.M.C.) while the exterior is coated with a main long fibre layer andan inner reinforcing layer near the metallic interface ring of the crank.The composite material was hot pressed and manufactured into crank body to reduce most of its weight. In the CMprocess, the long and short fibre layers were joined together by a metallic interface ring. Its characteristics include base composite material, interface ring, hollow square inner wall and exterior projected rib. The inner reinforcing layer provides the maximum bending strength and to reduce stress concentration of themetallic interface ring- to-crank attachment. The FEM model was then calibrated on the basis of the constituent material characterization and the definition of suitable boundary conditions in order to achieve a reliable simulation of the experimental tests and optimum design. Several designs of composite cranks were given to demonstrate the feasibility and applications of the proposed method.

Li/Al layered double hydroxide (Li/Al LDH), known as anionic clay, comprises positive charges, which are counter-balanced by interlayer anions. The material is capable of adsorbing anions through ion-exchange reaction. This property of LDH leads to its potential application in scavenging anionic contaminants, such as Cr(VI) in the waste streams. In this study, the adsorption of Cr(VI) by Li/Al LDH was investigated at 10 and 30 °C. The results showed that Cr(VI) adsorption was relatively rapid; however, a portion of adsorbed Cr(VI) was released over the reaction time and the releasing rate was dependent on reaction temperature. Particularly at 30 °C as high as 80.1% of adsorbed Cr(VI) was released after 24 h reaction. The release of adsorbed Cr(VI) is due to the deintercalation of Li+ from Li/Al LDH structures in aqueous solution and gibbsite, which was used as the precursor to synthesize Li/Al LDH, was the product of the deintercalation reaction. The Li deintercalation reaction of Li/Al LDH and its dependence on temperature of may be utilized to develop a method of treating Cr(VI)-containing wastes and recovering Cr(VI). That is, Li/Al LDH can be used as an adsorbent to remove Cr(VI) in wastewater. Then the Cr(VI)-bearing LDH particles are collected and re-suspended in hot water to enhance Li deintercalation and Cr(VI) desorption. Consequently Cr(VI) can be recovered from the solution and the solid product, i.e., gibbsite, can be recycled for further uses.

As part of a study examining the possible effects of organochlorine compounds on juvenile northern elephant seals (Mirounga angustirostris), blubber and blood samples were taken from animals present on the Año Nuevo (California) rookery, and from animals admitted for rehabilitation at The Marine Mammal Center (Sausalito CA). Blubber samples were collected from immobilized seals. A pre-cleaned 6 mm K-medic biopsy punch was used to extract the blubber from a 1 cm incision near the hip, near the dorsal mid point. Blood samples were taken from the extradural vein; two mL of serum was analyzed for organochlorine compounds. Blubber samples (approximately 0.1g) were ground with Na2SO4 and extracted with 20 mL hexane:methylene chloride (1:1). Sera samples were extracted using commercially available disposable C18 columns. The extracts were separated on a micro-Florisil column, and analyzed by HRGC-ECD. Lipid determination in the serum was obtained by colorimetric analysis with 20 microliters samples. Results from the analysis of replicates and standard reference materials showed good recoveries, precision, and accuracy for both the blubber and blood methods.

In this paper, the resin transfer molding (RTM) and compression molding manufacturing processes were used to fabricate composite wind turbine blades by stacking pieces of glass-fiber fabric, expandable polystyrene (EPS) foam and inserting parts in an interior pressure mold. The blade preform is a composite foam-filled sandwich structure, where the interior is an EPS foam layer while the exterior is coated with a main fiber layer, root reinforcing fiber layer and the parts are inserted. The inserted parts that were investigated were the I-beam, LED, conductor, root connection joint and repair patch. The reinforcing fiber layer was designed to provide maximum bending stiffness in the flexure to resist the stress concentration of the composite wind turbine blade. This research will also be used to develop adhesive bonding repair techniques for life extension of the damaged components in a wind turbine blade. A number of composite wind turbine blade constructions were fabricated to demonstrate the feasibility and applications of the proposed manufacturing method.

The effect of temperature, pH, cations, and caramelized sugars on L-alanine-induced germination of Bacillus licheniformis and B. cereus -7 spores was investigated. The germination of B. licheniformis spores was optimal at higher temperatures, with more than 99% germination at 37 and 55C, but none at 21C. B. cereus -7 spores germinated optimally at 37C, slowly at 21C, and much more slowly at 55C. The optimal pH for L-alanine induced spore germination in both Bacillus species was pH 7.0. Germination for B. cereus -7 spores was more sensitive to pH than B. licheniformis . With regard to the effect of ionic-inducement, for B. licheniformis potassium did not affect germination, but the divalent cations calcium and magnesium inhibited germination, especially at 100mM concentrations. Ferric ion inhibited germination at the lower concentrations but as the concentrations increased, this inhibitory property was lost. For B. cereus -7 spores, potassium, calcium, and magnesium were inhibitory to germination. Ferric ion was also inhibitory at the lower concentrations but was stimulatory at 50mM and higher. None of the caramels from four sugars (glucose, fructose, galactose, and lactose) affected L-alanine-induced germination of spores of B. licheniformis or B. cereus -7.