A Refinement on the Notion of Type I and II (Co)MoS Phases in Hydrotreating Catalysts

Hydrotalcite-like compounds with boron anions in the interlayer were obtained using a coprecipitation method. The effect of different pH values during the preparation was investigated and the effect on crystallinity and phase distribution studied. The influence of different methods of acidity regulation was also analyzed. The efficiency of synthesis of boron-containing anionic clays was evaluated, and the good thermal stability of the materials was noted. Surface characteristics were determined by X-ray photoelectron spectroscopy and correlated to the bulk properties obtained by X-ray diffraction and ²⁷Al and ¹¹B MAS NMR. The samples tested in gas-phase Beckmann rearrangement showed caprolactam formation, and the results were related to the surface features.     

Solid-state V NMR for characterization of vanadium-containing systems

This overview paper includes both published and original data of the current state of the field of ⁵¹V NMR in solid-state chemistry. Advantages and shortcomings of different NMR techniques in their applications to vanadium are discussed on the examples of their application to various vanadia based systems (including individual highly crystalline compounds, solid solutions, glasses, catalysts). New correlations between local structure of vanadium atoms and NMR parameters allowing to discriminate at least seven different types of vanadium sites (tetrahedral sites of Q⁰, Q¹ and Q² types; trigonal pyramids of 3=1 and 3=2 (V₂O₅ like) types; tetragonal pyramids of 4=1, 4=2 types) are proposed. It is demonstrated that competent combination of different NMR approaches permits now not only to describe different vanadium sites in highly crystalline and amorphous materials, but also to insight into the structural aspects of disorder in crystallinity as well as to reveal the behavior of different functional groups at elevated temperatures. The influence of low valence vanadium atoms on ⁵¹V NMR spectra is also discussed.     

用高分辨固体核磁共振谱模拟程序测定Y型分子筛的骨架硅铝比

用高分辨固体ＭＡＳ＾２９Ｓｉ－ＮＭＲ法测定Ｙ型分子筛的骨架硅铝比，直接可靠，优于依靠经验公式的Ｘ射线衍射法和红外光谱法，但谱峰重叠，严重妨碍实际应用。用固体核磁共振谱模拟程序处理分子筛的ＭＡＳ＾２９Ｓｉ－ＮＭＲ谱，不受谱峰重叠的限制。     

A Morphological Study of Poly[bis(trifluoroethoxy)phosphazene] Using High Resolution Solid-State 1H, 19F, 31P and 13C NMR Spectroscopy

High-resolution ¹⁹F, ¹H, ³¹P and ¹³C solid-state NMR methods were assessed to ascertain their suitability for studying the morphological behavior in the crystalline domain of phosphazene polymers with partially fluorinated side-chains. Poly[bis(trifluoroethoxy)phosphazene] (PBFP) was used as a sample system. Fast magic angle spinning (MAS), along with simultaneous ¹⁹F and ¹H decoupling using the xy-16 sequence, were employed, as this has proven to greatly improve resolution in ¹³C spectra of perfluorinated materials. Information obtained from Discrimination Induced by Variable Amplitude Minipulses (DIVAM) nutation experiments and cross-polarization (CP) methods aided the deconvolution analysis used to identify all components in the ¹H, ¹⁹F and ¹³C signals. DIVAM nutation experiments were also used to discriminate between signals from the amorphous and crystalline domain. The crystallinity in the solvent-cast PBFP was determined to be approximately 70%, which was seen to increase to approximately 80% in the heat-treated material, for all nuclei studied. A preliminary assignment was made for the crystalline signals in the ¹H and ¹³C spectra to the α-, β- and γ-phases. Therefore, high-resolution ¹³C and ¹H methods are valuable tools for morphological investigations into this class of polymer.     

EXAFS and MAS NMR studies of sodium molybdophosphate and sodium tungstophosphate glasses

The local order around molybdenum and tungsten atoms in various sodium molybdophosphate and sodium tungstophosphate glasses has been investigated using extended X-ray absorption fine structure (EXAFS). Both molybdenum and tungsten atoms are present in six-coordinated environment in these glasses. Magic angle spinning nuclear magnetic resonance (MAS NMR) of³¹P suggests that metaphosphate or neutral [POO_3/2] groups are present in these glasses.     

多Agent技术在多端线路保护系统中的应用

针对传统的输电线路继电保护所存在的不足,提出了Agent技术在T接线路保护中的应用方案,阐述了该保护系统的结构和决策过程。Agent可以由一个人、一些软件或智能系统构成,具有自治、协调和分布等特性。仿真结果表明,与传统的距离保护和纵联保护相比,该保护系统具有能够实现全线速动和不需要专用通信通道的优点。     

中厚板MAS轧制过程的有限元模拟

采用有限元软件ANSYS／LS-DYNA对MAS轧制过程及随后的展宽和精轧过程进行了模拟计算,分析了各变形阶段钢板的形状变化及不同MAS轧制参数对钢板边部形状的影响。结果表明：MAS轧制可以改善轧后钢板边部形状。钢板边部形状的改变不仅与MAS轧制的补偿面积有关,而且与MAS轧制段长度和压下量的比值有关,若MAS轧制参数选取不当,钢板边部会发生“过补偿”现象。根据计算结果选取MAS轧制参数,在中厚板轧机上进行了现场生产试验,效果良好。     

A platform for P2P agent-based collaborative applications

The operational environment can be a valuable source of information about the behavior of software applications and their usage context. Although a single instance of an application has limited evidence of the range of the possible behaviors and situations that might be experienced in the field, the collective knowledge composed by the evidence gathered by the many instances of a same application running in several diverse user environments (eg, a browser) might be an invaluable source of information. This information can be exploited by applications able to autonomously analyze how they behave in the field and adjust their behavior accordingly. Augmenting applications with the capability to collaborate and directly share information about their behavior is challenging because it requires the definition of a fully decentralized and dependable networked infrastructure whose nodes are the user machines. The nodes of the infrastructure must be collaborative, to share information, and autonomous, to exploit the available information to change their behavior, for instance, to better accommodate the needs of the users to prevent known problems. This paper describes the initial results that we obtained with the design and the development of an infrastructure that can enable the execution of collaborative scenarios in a fully decentralized way. Our idea is to combine the agent-based paradigm, which is well suited to design collaborative and autonomous nodes, and the peer-to-peer paradigm, which is well suited to design distributed and dynamic network infrastructures. To demonstrate our idea, we augmented the popular JADE agent-based platform with a software layer that supports both the creation of a fully decentralized peer-to-peer network of JADE platforms and the execution of services within that network, thus enabling JADE multiagent systems (MASs) to behave as peer-to-peer networks. The resulting platform can be used to study the design of collaborative applications running in the field.     

基于Agent理论的工业设计系统研究

在对工业设计过程分析的基础上 ,提出一个多Agent工业设计系统结构。该结构是用户驱动的、开放的和可重构的。给出各Agent的目标、功能、信息描述和结构     

智能控制-维护-管理系统的多Agent模型

为了在现代生产过程自动化系统中实现智能控制－－维护－管理系统，借助于多Agent系统理论，用Agent的概念和技术对自动化系统的各个部分进行分析、建模，建立起智能控制－－维护－管理系统的多Agent模型－CMMA Agent系统，给出了该模型的基本结构，分析了该模型中各个部分的功能，以及整个CMMA Agent系统的运行机制，探讨了Agent间通信实现的方法，该模型已在智能控制－－维护－管理系统平台的研制中得到了应用。