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41.
Citrus fibre was used as a substitute for sucrose in the formulation of wheat-corn-based extrudates produced using twin screw extruder. Replacing 5 % sugar with an equal quantity of fibre resulted in an increase in die pressure, torque and specific mechanical energy (SME), and consequently the expansion ratio increased. A further increase in fibre content to 10 % (e.g. reducing sugar to 0 %) had little effect on the extrusion processing parameters. The microstructure of extrudates examined by X-ray computed tomography shows that the porosity of the extrudates increased with increasing fibre content, which was attributed to an increased number of large pores. As the citrus fibre content increased, the maximum force required to fracture the extrudate increased; however, the cell wall thickness decreased. This suggests that the fibre component may have contributed to the strength of the cell wall. This study demonstrated a potential utilisation of fibre from by-product of juice extraction as a source of dietary fibre in low sugar-extruded products.  相似文献   
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Scheduling is an important aspect in the overall control of a flexible manufacturing system. The research presented focuses on production scheduling of jobs within a flexible manufacturing cell (FMC)–one type of flexible manufacturing system. Due to the complexity of the FMC scheduling problem, a 0–1 mixed-integer linear programming (MILP) model is formulated for M machines and N jobs with alternative routings. Although small instances of the problem can be solved optimally with MILP models, a two-stage Tabu Search (TS2 ) algorithm that minimises the manufacturing makespan (MS) is proposed to solve medium-to-large-scale problems more efficiently. During Stage I (construction phase), two heuristics are utilised to generate an initial feasible sequence and an initial MS solution. In Stage II (improvement phase), the acquired initial solutions from Stage I are combined with a Tabu Search meta-heuristic procedure that provides improved MS solutions. The TS2 algorithm provides tremendous savings in computational time for medium/large-sized multi-machine FMC problems.  相似文献   
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Androgen-dependent urinary constituents from males hasten reproductive maturation (the Vandenbergh effect) and disrupt peri-implantation pregnancy (the Bruce effect) in nearby females. Each of these effects can be mimicked in socially isolated females by direct administration of exogenous oestrogens. The current experiments were designed to determine the role of males' urinary 17β-oestradiol (E(2)) in their capacities to induce these effects. A preliminary experiment showed that both males on a phyto-oestrogen-rich soy-based diet and those on a phyto-oestrogen-free diet could induce both effects. For subsequent experiments, males were castrated and treated with either oil vehicle or E(2). Enzyme immunoassay was conducted on non-invasively collected urine samples from these males. Concentrations of urinary testosterone were subnormal in both conditions, but urinary E(2) was restored to the normal range for intact males in castrates given E(2). Urinary creatinine was also quantified as a measure of hydration and was significantly reduced in males treated with E(2). Castration diminished the capacity of males to promote growth of the immature uterus and also their capacity to disrupt blastocyst implantation in inseminated females. Injections of E(2) to castrated males restored both capacities. These data converge with other studies indicating that E(2) is the main constituent of male urine responsible for induction of both the Vandenbergh and the Bruce effects.  相似文献   
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The use is reported of the CSIRO Staple Strength/Length System, designed to provide measurements of staple strength and length as a potential aid to predicting the processing performance of greasy wool. A discussion of the merits of the energy and force results provided by the system and of an experimental examination of the effect of various independent parameters (such as sample regain, cross-section, and length) is presented.  相似文献   
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The trend toward the use of composite materials and digital electronics has renewed the need to quantify the effects of lightning strikes to airplanes, since composite structures do not provide shielding equivalent to that of metal aircraft, and digital systems are potentially more susceptible to upset by electrical transients than are analog electronic systems. A research program, called the Storm Hazards Program, has been run by the National Aeronautics and Space Administration (NASA) for the past eight years and has provided the first statistically significant measurements of the electromagnetic interaction between lightning and aircraft. A NASA-owned F-106B airplane has been flown through thunderstorms about 1500 times at altitudes between 5000 and 40000 feet (1500 to 12000 meters). The airplane, lightning-hardened and outfitted with special instruments, was hit by lightning 714 times. The types of measurements made and the results are described. The Storm Hazards Program has concluded, and interpretation of the data gathered is underway  相似文献   
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