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In this study, curled gelatin nanofiber was successfully electrospun from aqueous solution by elevating the spinning temperature. The effect of relative humidity was investigated on the morphology of gelatin nanofibers in the current study. It was observed that with the increase of relative humidity during electrospinning process, the proportion of the curled gelatin nanofiber increases. Futhermore, the curled gelatin nanofiber converted into helical structure when electrospun at relative humidity higher than 50%.

An attempt was made to replace the commonly used Fiber Reinforced Polymer (FRP) with aluminium alloy in NSM technique. This paper presents experimental investigation of interfacial bond behavior between NSM aluminium laminates and concrete structures. Aluminum laminates were mounted into premade slit of concrete with epoxy resin. Test results show that both maximum applied force and ductility of NSM reinforced specimens can be effectively improved by increasing bond length and width of aluminium laminates, whilst almost no change was found in average bond strength at the same time. Besides, the loaded end slip of specimen, corresponding to the maximum applied force, was mutually influenced by bond length and width of aluminium laminates. Furthermore, the measured strain distribution of aluminium laminates along the direction of bond length of specimen was found to be similar to that of FRP in NSM technique.

This paper presents an experimental study on the bond performance of aluminum alloy plate-to-concrete interface via a series of simple shear test. The parameters examined include the bond length and width of the aluminum alloy plates. Two types of failure modes were observed through the experimental program. The test results demonstrate the bond strength of the aluminum plate-to-concrete interface depends strongly on the coupling effect of bond length and width. The variation of the aluminum strain distribution along the bond length against the applied load clearly illustrates the existence of an effective bond length. The load-slip curves show that the bond width has more sensitive effect to the bond strength.

A magnetic-controlled detection system, with a rectangular solenoid coil in a waveguide test fixture, is proposed for radar absorbing coatings. By applying Ku-band rectangular waveguide, the field patterns at different positions, the reflection coefficientS11and its variation of several coating samples are simulated and measured under current loaded from 0 to 1.0 A. The results show that this detection system is repeatable and stable, and also reliable with the error of less than 10%.

The effects of Cemfiber on the workability, mechanical properties, resistance to chemical corrosion and drying shrinkage of High-Performance Concrete (HPC) have been studied systematically. The results show that: (1) the effects of Cemfiber on the workability of HPC are related to parameter of mix proportion. Generally speaking, Cemfiber does not reduce the workability of HPC; (2) the effect of Cemfiber on the compressive strength and flexural strength is very small; (3) the HPC incorporated with Cemfiber has high resistance to corrosion of hydrochloric acid; (4) Cemfiber may reduce drying shrinkage of HPC significantly; (5) Cemfiber may increase cracking resistance of HPC resulting from drying shrinkage.

Polypropylene fiber is a new measure to prevent plastic cracks of concrete. Effects of the parameters, such as dosage and types of fibers, on the plastic cracks were studied systematically. The properties of cracking resistance of mortar, ordinary concrete and high performance concrete were investigated by using samples of two types in shape. The results show that: (1) polypropylene fibers may increase the cracking resistance of concrete further; (2) as smaller quantity of cement and higher quantity of aggregate as possible should be used to prevent concrete form cracking; (3) the main reason why polypropylene fibers increase cracking resistance of concrete is that they increase strain capacity of concrete at early age, decrease shrinkage strain, improve plastic tensile strength and decrease tensile stress of the capillary.

The ASTM C1202 method is observed that the total electric charge passed is not an ideal indicator for classification of concrete quality when different binders are considered. Considering the drawback of the ASTM 1202 method, a simple modification to the ASTM C1202 method is recommended. The modification involves an additional test using curing water as electrolyze solution. The difference in the total charge passed obtained between standard test and test performed in curing water is suggested as an indicator for concrete quality. The test results show that there exists a good correlation between the ACSIRO and the ASTM C1202 methods. The relationship can be formulated as a linear function.