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21.
实验研究了球磨时间对纳米ZrO2水悬浮液性质的影响。结果表明,粒径小于15nm ZrO2在SND6800球磨剂的水相中球磨2h制备的悬浮液,可稳定存在14天。在SND6800球磨剂与ZrO2的质量比为5:95时,球磨时间对粒子粒度、悬浮液的密度和pH值以及沉降率影响不大;但对悬浮液的吸光度、表面张力和黏度有明显的影响。球磨时间50h是悬浮液的吸光度及表面张力最大,而黏度是球磨40h时最大。  相似文献   
22.
蒋玲  李淑勉  李占才  李洋 《光谱实验室》2012,29(4):2032-2036
以造纸污泥中提取的木质素和二乙基环氧丙基胺(简称环氧胺单体)为原料,通过接枝共聚反应制备了木质素胺絮凝剂(DL),并确定了最佳合成工艺条件,同时采用傅里叶变换红外光谱(FTIR)对产物结构进行了表征。结果表明,以1.5mo1·L-1NaOH为催化剂,木质素和环氧胺单体的质量比为1:1,于70℃下接枝反应2h时,所得絮凝剂DL对3种模拟染料废水的脱色率分别可达89.66%、74.10%和89.84%,通过比较DL与木质素的絮凝效果以及絮体微观形貌,对DL的絮凝机理进行了初步探讨。  相似文献   
23.
信息系统中的可移动Agent   总被引:1,自引:0,他引:1  
介绍了可移动Agent的特性,可移动Agent可在异质计算机网络中移动,它能感知网络的状态,监控系统并与其它Agent进行交互,导航模型可以让Agent适应网络的变化并自主制定导航计划,从而方便、有效、智能地完成信息检索的任务.  相似文献   
24.
The Schelling segregation models are “agent based” population models, where individual members of the population (agents) interact directly with other agents and move in space and time. In this note we study one-dimensional Schelling population models as finite dynamical systems. We define a natural notion of entropy which measures the complexity of the family of these dynamical systems. The entropy counts the asymptotic growth rate of the number of limit states. We find formulas and deduce precise asymptotics for the number of limit states, which enable us to explicitly compute the entropy.  相似文献   
25.
The principle aim of this paper is to reconsider the suitability of Austin and Searle’s Speech Act theory as a basis for agent communication languages. Two distinct computational interpretations of speech acts are considered: the standard “mentalistic” approach associated with the work of Cohen and Levesque which involves attributing beliefs and intentions to artificial agents, and the “social semantics” approach originating (in the context of MAS) with Singh which aims to model commitments that agents undertake as a consequence of communicative actions. Modifications and extensions are proposed to current commitment-based analyses, drawing on recent philosophical studies by Brandom, Habermas and Heath. A case is made for adopting Brandom’s framework of normative pragmatics, modelling dialogue states as deontic scoreboards which keep track of commitments and entitlements that speakers acknowledge and hearers attribute to other interlocutors. The paper concludes by outlining an update semantics and protocol for selected locutions. Rodger Kibble is a Lecturer in the Department of Computing, Goldsmiths College, University of London. He has worked as a researcher at the Information Technology Research Institute, University of Brighton, and the School of Oriental and African Studies, University of London. He received his PhD from the Centre for Cognitive Science in the University of Edinburgh in 1997. He has published conference papers and journal articles in the formal semantics of natural language, natural language generation, anaphora resolution, dialogue modelling, argumentation and multi-agent communication; and coedited Information Sharing: Reference and Presupposition in Language Generation and Interpretation (CSLI, 2002).  相似文献   
26.
A new compound floatation agent for graphite is described. It is very effective on the floatation of cryptocrystalline graphite. The structure and composition of the new floatation agent are studied by using Raman and infrared spectra.  相似文献   
27.
In a recent work [D. Campos, J.E. Llebot, V. Méndez, Theor. Popul. Biol. 74 (2009) 16] we have introduced a biological version of the Evolutionary Minority Game that tries to reproduce the intraspecific competition for limited resources in an ecosystem. In comparison with the complex decision-making mechanisms used in standard Minority Games, only two extremely simple strategies (juveniles and adults) are accessible to the agents. Complexity is introduced instead through an evolutionary learning rule that allows younger agents to learn taking better decisions. We find that this game shows many of the typical properties found for Evolutionary Minority Games, like self-segregation behavior or the existence of an oscillation phase for a certain range of the parameter values. However, an analytical treatment becomes much easier in our case, taking advantage of the simple strategies considered. Using a model consisting of a simple dynamical system, the phase diagram of the game (which differentiates three phases: adults crowd, juveniles crowd and oscillations) is reproduced.  相似文献   
28.
孟朝阳 《光谱实验室》2003,20(3):471-474
本文介绍了第三代安眠药亿梦返的化学结构和相关的药理性质,应用高效液相色谱和气-质联用方法定性和定量地分析了“亿梦返”的主要成分——佐匹克隆,并初步探讨其在人体内的致死量。  相似文献   
29.
MADCE中的多Agent协作策略研究   总被引:4,自引:0,他引:4  
描述Agent间的交互关系,提出了一种基于域的多Agent协作策略.该策略限定信息传播和共享的范围,实现Agent间负载的动态调整,它遵循就近原则,在局部范围内寻找最优的合作者,协作完成子计划,从而平衡负载,降低开销,扩大分布式计算环境的处理能力.为MADCE提供了一种有效的协作策略,并给出了算法描述、评价及例示.  相似文献   
30.
Sustained signal activation by hydroxyl radicals (⋅OH) has great significance, especially for tumor treatment, but remains challenging. Here, a built-in electric field (BIEF)-driven strategy was proposed for sustainable generation of ⋅OH, thereby achieving long-lasting chemodynamic therapy (LCDT). As a proof of concept, a novel Janus-like Fe@Fe3O4−Cu2O heterogeneous catalyst was designed and synthesized, in which the BIEF induced the transfer of electrons in the Fe core to the surface, reducing ≡Cu2+ to ≡Cu+, thus achieving continuous Fenton-like reactions and ⋅OH release for over 18 h, which is approximately 12 times longer than that of Fe3O4−Cu2O and 72 times longer than that of Cu2O nanoparticles. In vitro and in vivo antitumor results indicated that sustained ⋅OH levels led to persistent extracellular regulated protein kinases (ERK) signal activation and irreparable oxidative damage to tumor cells, which promoted irreversible tumor apoptosis. Importantly, this strategy provides ideas for developing long-acting nanoplatforms for various applications.  相似文献   
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