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51.
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基础下早期人防工程处理的实践与探索 总被引:1,自引:0,他引:1
地下早期人防工程的处理是当前城市建设中经常遇到的问题。鲁南商城工程地上六层 ,地下一层 ,场区地下有一组早期人防工程 ,距地面 7 0m ,距拟建工程基底不足 2 0m ,影响了工程建设。设计人员通过对早期人防工程的加固处理 ,并在拟建工程设计中运用补偿基础理论 ,消除了地下早期人防工程的不良影响 ,使工程建设顺利进行。该工程实例对同类问题的解决具有实际意义。 相似文献
53.
有机锑和添加剂对聚氯乙烯热稳定性能的协同效应 总被引:7,自引:0,他引:7
采用HAAKE流变仪研究了在添加自制有机锑热稳定剂及各种助剂后的硬质聚氯乙烯(PVC)的热稳定性能,同时探讨了它们的防初期着色性能。结果表明:随着有机锑稳定剂用量的增加,PVC样品的动态稳定性能和防初期着色都变好;添加对叔丁基邻苯二酚(TBC)时有较好的防初期着色性能和较好的动态稳定性能;硬脂酸钙和有机锑热稳定剂并用有很好的协同效用,但是随着用量增大,PVC的初期颜色会逐渐变深;巯基乙酸异辛酯对初期颜色和长期稳定性能的影响有一个最佳的添加量。 相似文献
54.
In this paper, we employ a nonlinear adaptive mechanism to globally stabilize nth-order reactions. 相似文献
55.
Tsuyoshi Takahashi Masahito Kitou Michio Asai Mitsuyasu Kido Tomio Chiba Junzou Kawakami Yoshiaki Matsui 《Electrical Engineering in Japan》1994,114(2):18-33
Power system control equipment needs higher sensitivity and operational reliability. Advanced voltage control equipment is needed for reducing the frequency of tap changes and improving the characteristics (the relationship between the actual voltage and reference voltage) of the voltage to meet today's power system requirements. However, these objectives are in a trade-off relationship. Studies of voltage control derived from a knowledge base suitable for electric power systems can satisfy these objectives using fuzzy inference. Compared with corresponding conventional equipment, the new equipment improved the deviation of 30 min average voltage of 30 percent. This paper describes the design concept of new voltage control equipment using fuzzy inference. In addition, field test results are described along with rules of fuzzy inference, membership functions, and the deviation of 30 min average voltage through detailed simulation. 相似文献
56.
Sarrazin Jean-Christophe; Giraudo Marie-Dominique; Pailhous Jean; Bootsma Reinoud J. 《Canadian Metallurgical Quarterly》2004,30(3):411
In 3 experiments, the authors studied the organization of spatiotemporal information in memory. Stimuli consisted of configurations of dots, presented sequentially. The stimuli were either proportional, with interdot distances corresponding to interdot durations, or not proportional, with interdol distances not corresponding to interdot durations. After a learning phase, participants reproduced the spatial (Experiment 1), temporal (Experiment 2), or spatial and temporal (Experiment 3) characteristics of the target 60 times in succession. In the nonproportional conditions, effects of variable interdot durations or distances on the reproduction of, respectively, constant distances (tau effect) or durations (kappa effect) were observed, whereas no such effects were observed when variable distances or durations were to be produced. Tau and kappa effects influenced the accuracy but not the variability of responses. The results are discussed in light of the distinction between properties of the stabilized mental image and the process of stabilization. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
57.
Ying‐Hung So 《Polymer International》2006,55(2):127-138
Poly(2,4‐dimethyl‐1,4‐phenylene oxide) (PPO), poly(benzo[1,2‐d:5,4‐d′]bisoxazole‐2,6‐diyl‐1,4‐phenylene) (PBO) and poly(benzo[1,2‐d:4,5‐d′]bisthiazole‐2,6‐diyl‐1,4‐phenylene) (PBZT), which are polymers with extended conjugated structures, undergo a self‐sensitized photo‐induced electron‐transfer reaction. A second component is not required. This article presents many similar observations on these polymers when they are exposed to light and evidence to support the proposed photo‐induced electron‐transfer mechanism. Methods to stabilize these polymers against photo‐oxidation are also described. Workers investigating other conjugated polymeric systems may find the experimental methods, observations and polymer stabilization approaches discussed in this review useful. Copyright © 2005 Society of Chemical Industry 相似文献
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Biphenol monoacrylate (AL) was combined with a traditional hindered phenolic‐based binary antioxidant system to form a ternary stabilization system for the purpose of further improving the thermal–oxidative stability of polyamide 6 (PA6). The thermal stabilization effect of the antioxidant AL on PA6 was studied in terms of the reduced viscosity, the chemical structure, the yellow index, and the mechanical properties. The results showed that the antioxidant AL, with the proper chemical structure, could improve the thermal stability of PA6 effectively through a unique bifunctional stabilizing mechanism. The interaction of the molecules of PA6 with the antioxidant AL was investigated. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2008 相似文献
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