ADI-FDTD Method With Fourth Order Accuracy in Time

This letter presents an unconditionally stable alternating direction implicit finite-difference time-domain (ADI-FDTD) method with fourth order accuracy in time. Analytical proof of unconditional stability and detailed analysis of numerical dispersion are presented. Compared to second order ADI-FDTD and six-steps SS-FDTD, the fourth order ADI-FDTD generally achieves lower phase velocity error for sufficiently fine mesh. Using finer mesh gridding also reduces the phase velocity error floor, which dictates the accuracy limit due to spatial discretization errors when the time step size is reduced further.     

憎水性栀子蓝色素制备的研究

以浓盐酸为催化剂,采用乙酸酐酯化处理水溶性栀子蓝色素,制备了憎水性栀子蓝色素.探讨了栀子蓝色素与乙酸酐料液比、反应时间和反应温度等因素对憎水性栀子蓝色素色价的影响.结果表明:采用料液比1:20,在常温下反应4 h,为制备憎水性栀子蓝色素的最优条件.同时,通过红外光谱、可见吸收光谱及溶解性对栀子蓝色素的酯化改性进行了初步的探讨.     

Ionothermal synthesis of a three-dimensional zinc phosphate with DFT topology using unstable deep-eutectic solvent as template-delivery agent

A three-dimensional zinc phosphate compound with DFT topology, designated as ZnPO₄-EU1, has been synthesized by an ionothermal approach from the system HF-ZnO–P₂O₅-choline chloride-imidazolidone. Ethylenediamine, derived from decomposition of the imidazolidone component of the deep-eutectic solvent (DES) itself, is delivered to the synthesis and serves as an appropriate template for ZnPO₄-EU1. Experiments in which the synthesis conditions were varied showed that ZnPO₄-EU1 may be prepared over a wide molar ratio of P/Zn = 0.55–13.0. Powder X-ray diffraction patterns have been obtained at intervals to track the crystallization process of this material. The experimental data show that Zn₃(PO₄)₂ · 4H₂O (a dense phase) was first isolated from the DES after reaction for 1 h. Subsequently, the pure phase of ZnPO₄-EU1 was obtained with increasing crystallization time from 12 h to 72 h. The experimental results show that the nucleation and crystallization take place with relatively low levels of solvent degradation, demonstrating that zinc phosphate with a three-dimensional framework can be synthesized by in situ generation of an appropriate template using an unstable DES at high temperatures (150–200 °C).     

Automating application software generation

Many approaches have been proposed to enhance software productivity and reliability. These approaches typically fall into three categories: the engineering approach, the formal approach and the knowledge-based approach. But the optimal gain in software productivity cannot be obtained if one relies on only one of these approaches. This paper describes the work in knowledge-based software engineering conducted by the authors for the past 10 years. The final goal of the research is to develop a paradigm for software engineering which integrates the three approaches mentioned above. A knowledge-based tool which can support the whole process of software development is provided in this paper.     

An experiment for showing some kind of artificial understanding

In this paper we design an experiment which can be depicted as a simple scenario, a very limited 'world'. In this world, there are an actor that can pursue a project and an observer that is keeping its eyes on the actor. We try to show in the experiment that the observer can to some degree understand the actor based on its knowledge and some metaphors, i.e. understand what the actor is doing and why. As the conclusion of this experiment, we try to show some features of 'understanding'. These are (1) that 'understanding' has to be based on some preliminary knowledge; (2) that 'understanding' is a process of incremental learning; (3) that, as for symbolic systems, some metaphors are necessary for mapping real entities into concepts in mind.     

催化裂化汽油脱硫助剂TS-01的工业试验

中国石油化工股份有限公司九江分公司在I套催化裂化装置进行了TS—0l催化裂化汽油脱硫双功能助剂的工业应用。结果表明：TS—0l剂对催化裂化汽油有较好的脱硫效果。当TS—0l剂注入原料中的量为70μg／g时，对催化裂化汽油的硫脱除率约为20％；注入量为120μg／g时，硫脱除率可达到25％-30％。汽油中脱除的硫主要以硫化氢形态转移至于气、液化气中。TS—01剂对产品分布及产品其它质量无明显影响，该剂亦有良好的金属钝化效果。     

Commercial Test of Multi-functional Desulfurizing Agent TS-01 for Gasoline in FCC Process

Experimental use of multi-functional desulfurizing agent TS-01 for FCC gasoline in the FCC unit of SINOPEC Jiujiang Company shows that the multi-functional desulfurizing agent can effectively remove various kinds of sulfur in FCC gasoline and diesel fuel and fulfill passivation on heavy metals.     

Perceived risk and trust associated with purchasing at electronic marketplaces

Understanding consumer behaviour is of vital importance to consumer-oriented e-business models today. In this paper, we study the relationships between consumer perceptions of risk and trust and the attitude towards purchasing at a consumer-to-consumer electronic marketplace (EM). Typical for EM settings is that consumer behaviour is subject to perceptions of the selling party as well as of the institutional structures of the intermediary that is operating the EM. Building upon the well-established literature of trust, we consider the concepts of intermediary trust and seller trust. We extend this categorisation by introducing the concepts of intermediary risk and seller risk. We developed measurement instruments for intermediary risk and seller risk. All measurement scales have acceptable alphas and are unidimensional. An empirical study is conducted to explore the relationships between the risk and trust types and consumer purchase attitude. The results reveal significant, direct effects of seller trust and seller risk. Second-order effects of intermediary trust and intermediary risk are investigated and reported. The paper concludes with general observations and recommendations for research and practice.     

新型超微晶软磁合金FePCCuMoSi微观结构缺陷的正电子湮没研究

用正电子湮没方法研究了新型超微晶软磁合金的微观结构缺陷，样品选用的是在不同温度下退火的Ｆｅ８１Ｐ１２Ｃ３Ｃｕ１Ｍｏ０．５Ｓｉ２．５合金，结果表明，合金的微观结构构陷大小，密度随退火温度有规律地变化，这种现象可能与非晶的晶化过程有关。     

肝癌碘油栓塞后肝区平片所见碘油沉积量与疗效关系

本文分析了90例肝癌肝动脉灌注化疗碘油栓塞后,肝区平片所见碘油沉积量和疗效的关系。碘油沉积分为多,中,少三组,从ATP下降,肿瘤缩小率及一年生存率三方面比较。结果沉积多的与中等组三项都有显著差别;沉积中等的与少的组差别不明显。说明碘油沉积要达到一定的量后,疗效才会显著提高。同时分析了影响碘油沉积的几个因素。