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41.
We prove that any simplification order over arbitrary terms is an extension of an order by weight, by considering a related monadic term algebra called the spine. We show that any total ground-stable simplification order on the spine lifts to an order on the full term algebra. Conversely, under certain restrictions, a simplification ordering on the term algebra defines a weight function on the spine, which in turn can be lifted to a weight order on the original ground terms which contains the original order. We investigate the Knuth–Bendix and polynomial orders in this light. We provide a general framework for ordering terms by counting embedded patterns, which gives rise to many new orderings. We examine the recursive path order in this context. 相似文献
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In the dieless drawing technology the drawing dies are replaced by a heating device, generally by an induction coil. Bars of different cross-sections, round or even rectangular, with varying dimensions along the length can be produced. By using a cooling box in connection with the heating device this deformation process may also be employed for a thermomechanical treatment of steels. The special cooling strategy with low cooling rates at high temperatures (during ferrite formation) and higher cooling rates at lower temperatures favours the formation of multiphase microstructures (ferrite - bainite/martensite) with a low yield strength but a strong work hardening effect. The experiments were carried out on rods with a diameter of 16 mm of a plain low carbon steel (0.1%C, 0.7%Mn). The specimens were locally heated up to the maximum temperature ?max that initiates the dieless drawing process, and subsequently cooled with different coolants. The change in yield strength and tensile strength and the corresponding change in the ratio of both could be achieved by variation of ?max and the cooling conditions. The multiphase microstructure with desired mechanical properties was produced at a strain of about more than 0.45 within the region of ?max ≈ 900–1000°C and a finale cooling rate of about 20 K/s. 相似文献
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Ursula Fillat Montserrat Pepió Teresa Vidal M. Blanca Roncero 《Biomass & bioenergy》2010,34(12):1896-1905
Fiber crops constitute a good alternative to wood fiber for manufacturing pulp and paper. In fact, fiber plants like flax surpass wood fiber in some technical respects and also in the environmental benignity of their processing. In this work, flax fiber was subjected to environmentally friendly bleaching sequences in order to obtain a high-quality pulp. The totally chlorine-free sequences (TCF) used for this purpose (LE and LRE) included an enzyme treatment with laccase in the presence of HBT as mediator (L stage), an alkaline extraction (E stage) and a reductive treatment with NaBH4 (R stage). The operating conditions for the L stage (laccase and HBT doses, reaction time and oxygen pressure) were optimised by using a sequential statistical plan to assess their influence on pulp properties after the E stage.Mathematical models accurately predicting brightness and kappa number in terms of the previous four variables were developed based on which the most influential factors were the laccase and HBT rates, and treatment time. By contrast, oxygen pressures of 0.2–0.6 MPa in the reactor had no effect on brightness or kappa number. The flax pulp obtained contained some oxidized cellulose that was partially degraded in the alkaline extraction step and reduced viscosity as a result. The viscosity loss associated with the presence of oxidized cellulose in the control and enzyme-treated pulp samples was efficiently recovered by using a reductive stage with sodium borohydride. Effluent was also analysed in order to assess the environmental impact of the process. 相似文献
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与其他历史悠久的城市一样,丹麦首都哥本哈根市是有序和随意的规划设计共同作用的结果,它不仅继承了城市的人文建筑遗产,还体现了城市有机发展的过程.本项目位于哥本哈根市中心,紧挨着斯特罗里耶步行街. 相似文献
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To date, more than 1.3 million service members have served in the Global War on Terrorism. These men and women and their families face a range of stressful situations and must navigate many important tasks after a deployment. This article outlines four of the tasks of reintegration: redefining roles, expectations, and division of labor; managing strong emotions; abandoning emotional constriction and creating intimacy in relationships; and creating shared meaning. For each task, potential challenges are discussed and suggestions for how psychologists can support families are described. In addition, potential red flags and indicators that more intensive services may be warranted are reviewed. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
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The innovative principle of enzymatic sensors applied to monitor the feeding process in disposable bioreactors is described. Innovative is the type of enzyme immobilized within the 'paste' to monitor L-glutamate. Innovative is the application of the miniaturized disposable sensor developed at C-CIT AG for continuous monitoring. The sensor allows the amount of the digested nutrient to be estimated from the amperometric signal. Innovative is the wireless signal transduction between the sensor mounted to the bioreactor and the signal receiver. An example of a process control run is given and, also, the biocompatibility and the specifications of the biosensors. The comparison of results evaluated by different analytical methods is discussed. 相似文献