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61.
Michael M. Mandanas Walter Shaffer James H. Adair 《Journal of the American Ceramic Society》2002,85(9):2156-2160
A dispersion scheme for aqueous processing of manganese zinc ferrite suspensions is presented. The addition of oxalic acid leads to the formation of a uniform negative charge on the surface such that a cationic polyelectrolyte, polyethyleneimine (PEI), adsorbs and provides electrosteric dispersion. At 0.5 w/w (weight percent with respect to the dry powder) oxalic acid addition, there is a relatively uniform negative surface charge (approximately −30 mV) within the suspension pH range investigated (3–10), eliminating the isoelectric point (pH ∼7.6) present for the as-received metal oxide powder. At the addition of 0.5 w/w PEI on an oxalate-treated surface, the surface charge is constant and positive (∼20 mV) through a wide pH range, ∼5–10. The resulting rheological data for passivation–dispersion of relatively high-solids manganese zinc ferrite suspensions (∼80 wt%) demonstrate improved colloid stability with improved rheological properties. The resulting apparent viscosity and Bingham yield point is 0.01 Pa·s (12.0 cP) and 0.24 Pa (2.4 dynes/cm2 ), respectively. A sulfonated napthalene-based dispersant, typically used in industry, gives an apparent viscosity and Bingham yield point of 0.03 Pa·s (32 cP) and 3.1 Pa (31 dynes/cm2 ), respectively. 相似文献
62.
该文介绍一种简单、可靠、小巧的转速传感器。它的特点是在强振环境下仍具有很高的可靠,可用于坦克底盘、重型工程机械,燃气轮机组等机械作为转速监测。 相似文献
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65.
浅议朱提商业街规划设计中的文化传承 总被引:2,自引:2,他引:0
以朱提文化商业街为例,从地域文化分析、规划设计原则、人文环境设计、建筑造型四方面探讨了设计中的文化传承问题,以展示现代商业街街区的文脉,体现城市的文化。 相似文献
66.
《Canadian Metallurgical Quarterly》2003,39(3):581
The role of attention processes as possible mediators between family environment and school readiness was analyzed with data from 1,002 children and their families. Data on children's sustained attention, impulsivity, and school readiness (i.e., cognitive, achievement, language, and social development) were obtained at 54 months of age, and quality of the family environment was assessed throughout the first 54 months. Mediation tests showed that children's sustained attention partially accounted for the link between family environment and achievement and language outcomes. Impulsivity partially accounted for the link between family environment and achievement, social competence, and externalizing behaviors. The roles of sustained attention and of inhibition of impulsive responding in the relation between family characteristics and school readiness are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
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68.
V. Geros M. Santamouris S. Amourgis S. Medved E. Milford G. Robinson K. Steemers S. Karatasou 《Renewable Energy》2006,31(15):2447-2459
The present paper aims to present a distant-learning training module that concerns the environmental design of urban buildings. The whole approach attempts to integrate topics that concern the design of urban buildings from various points of views, e.g. active and passive systems, automation systems, indoor air quality, economic aspects, energy and resources management. The package offers both printed and electronic material that gives the possibility to the students to study the various topics by using different educational methods. Additionally, the present package contains software tools that permit the students to examine real or hypothetical situations and to study further the influence of various parameters that concern the environmental building design. 相似文献
69.
Environment as a first class abstraction in multiagent systems 总被引:2,自引:1,他引:1
The current practice in multiagent systems typically associates the environment with resources that are external to agents and their communication infrastructure. Advanced uses of the environment include infrastructures for indirect coordination, such as digital pheromones, or support for governed interaction in electronic institutions. Yet, in general, the notion of environment is not well defined. Functionalities of the environment are often dealt with implicitly or in an ad hoc manner. This is not only poor engineering practice, it also hinders engineers to exploit the full potential of the environment in multiagent systems. In this paper, we put forward the environment as an explicit part of multiagent systems.We give a definition stating that the environment in a multiagent system is a first-class abstraction with dual roles: (1) the environment provides the surrounding conditions for agents to exist, which implies that the environment is an essential part of every multiagent system, and (2) the environment provides an exploitable design abstraction for building multiagent system applications. We discuss the responsibilities of such an environment in multiagent systems and we present a reference model for the environment that can serve as a basis for environment engineering. To illustrate the power of the environment as a design abstraction, we show how the environment is successfully exploited in a real world application. Considering the environment as a first-class abstraction in multiagent systems opens up new horizons for research and development in multiagent systems. 相似文献
70.
在对山西资源现状分析的基础上,就山西如何走新型工业化道路,如何正确地处理山西日益突出的生态环境,自然资源和社会经济发展的矛盾问题,提出了对策和建议。 相似文献