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SBA-15 supported Mo, CoMo, NiMo catalysts were prepared. The supports were characterized by surface area, pore size distribution, and X-ray diffraction. The finished catalysts in oxide state were characterized by surface area analysis and X-ray diffraction in the region where the molybdenum oxide lines are seen. The sulfided catalysts were examined by oxygen chemisorption at low temperatures. The catalytic functionalities of these catalysts viz hydrodesulfurization (HDS) and hydrogenation were evaluated on sulfided catalysts. The catalytic activities of these catalysts are compared with γ-Al2O3- and SiO2-supported catalysts. An attempt is made to understand the relationship between oxygen chemisorption and catalytic activities with the help of other characterization results.

A series of catalyst with Mo loading from 2 to 14 wt.% on MgO–Al 2 O 3 mixed oxide support was prepared by incipient wetness impregnation method. Pure MgO and Al 2 O 3 were prepared by using Mg(NO 3 ) 2 ·6H 2 O and Al(NO 3 ) 3 ·9H 2 O salt solutions and urea as hydrolyzing agent. MgO–Al 2 O 3 (1:1) mixed oxide was prepared by co-precipitation of appropriate quantities of magnesium nitrate and aluminum nitrate salts. BET surface area, pore volume, pore size distribution, TPR, acidity and acid strength distributions of catalysts and supports were measured. MgO–Al 2 O 3 (1:1) mixed oxide showed a biomodal pore size distribution. LTOC and TPR results show that an optimum 8% Mo on MgO–Al 2 O 3 is sufficient to form MoO 3 monolayer. TPR technique can also be used as a vital tool to determine the monolayer coverage. HDS activity has been correlated with LTOC. Introduction of basic MgO in the lattice of Al 2 O 3 moderates the strong acidity in MgO–Al 2 O 3 . Impregnation of acidic MoO 3 species further enhances the acidity favorable for HYC.

Low-frequency noise measurements were performed on thin metallic very large-scale integration (VLSI) interconnects of three different geometries. These measurements were carried out under stressing current densities between 1.0/spl times/10/sup 5/ A/cm/sup 2/ and 2.2/spl times/10/sup 6/ A/cm/sup 2/ at different ambient temperatures up to 280/spl deg/C, in order to investigate the dependence of low-frequency noise on the geometrical shape of the VLSI interconnects. The behavior of these samples under these conditions is analyzed in this letter.

The preliminary results of integrating mobile tablet-PC technology and supporting classroom management software (CMS) in undergraduate electronic engineering technology courses is discussed in this WIP paper. The use of NetSupport School CMS in conjunction with a tablet-PC, improves course delivery by centrally instructing students on their tablet-PCs, broadcast the dynamic screen contents along with digital ink annotations in real-time, maintain student attention by monitoring student activities and Web usage, and save time by quickly polling the class and showing responses instantly. The students can share their class work instantly with other students or the instructor. The instantaneous sharing of work in real-time improves collaboration between students and faculty and adds new dimensions to the learning environment in the classroom. The initial results show a significant improvement in studentspsila class performance and learning experience. The technology integration, redesigned course, pedagogical approach, student experiences, and results are discussed in this WIP paper.

The paper describes the teaching experience gathered along four years, including the choices of robotics platform, simulator, typical experiments and projects we have conducted for students. We also discuss our efforts and plans to develop a hands-on laboratory course for the education in Robotics and Automation. The course is designed to the multidisciplinary and can be offered for engineering and non-engineering students. In order to offer hands-on experience in operating the robots and design of manufacturing works cells, a fully-equipped robotics laboratory has been established to provide basic as well as advanced experiments, to address the needs of students at different education levels.

Supporting efficient and reliable data transmission over wireless networks has been subject of continuous research over the last decade. The major concerns were in the area of security. The data confronts the security hazard during transmission over a wireless network. Indeed, it is relatively easy to eavesdrop on video/audio conversations, or intercept and modify data packets. Anyone with a PC and access to the public network has the ability to capture network traffic, potentially compromising the privacy and the reliability of the applications. Hence, it is mandatory for wireless applications to guarantee authentication, confidentiality and integrity of data. In this paper we present the security issues to be handled for safe and secure implementation of wireless LAN technology. Also discussed is the IEEE 802.11b standard, which is equipped with a privacy facility.

Publisher Summary This chapter discusses the catalytic functionalities of USY zeolite-supported hydrotreating catalysts. USY zeolites of varying silicon/aluminium (Si/Al) ratios are used as support for molybdenum (Mo), nickel molybdenum (NiMo), cobalt molybdenum (CoMo), and NiW catalysts. Both the effect of variation of Si/A1 ratio of the zeolite and Mo content on support at fixed Si/Al ratio is studied. The catalysts are examined by X-ray diffraction (XRD), oxygen chemisorptions, and temperature programmed reduction (TPR) techniques. The hydrodesulfurization and hydrogenation reaction studies indicate that these catalysts are more active than γ-A1 2 O 3 supported catalysts, and the increase in activities may be attributed to an increase in Mo dispersion and reducibility. Oxygen uptake correlates well with the catalytic activity.