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The prosperity of electronic commerce has changed the traditional trading behaviors and more and more people are willing to conduct Internet shopping. However, the exponentially increasing information provided by the Internet enterprises causes the problem of overloaded information, and this inevitably reduces the customer''s satisfaction and loyalty. One way to overcome such a problem is to build personalized recommender systems to retrieve product information that really interests the customers. For products that people may purchase relatively often, such as books and CDs, recommender systems can be built to reason about a customer''s personal preferences from his purchasing history and then provide the most appropriate information services to meet his needs. On the other hand, for those commodities a general customer does not buy frequently, for example computers and home theater systems, more appropriate are the kinds of recommender systems able to retrieve optimal products based on the customer''s current preferences obtained from the iterative system–customer interactions. This paper presents the above two kinds of recommender systems we have developed for supporting Internet commerce. Experimental results show the promise of our systems. [Copyright &y& Elsevier]

Abstract: Plasma treatment of multi-walled carbon nanotubes (MWCNTs) using an atmospheric pressure hydroxyl radical (OH) source has been monitored with micro-Raman spectroscopy. We use dispersion behavior of the intensity ratio, band position, and linewidth of the D, G, D′, and G′ bands to probe the defect formation and oxidation process in MWCNTs. A simple kinetic model is adopted to interpret the observed dispersion trends in plasma-treated MWCNTs. X-ray photoelectron spectroscopic analysis, scanning electron microscopy inspection, and Raman dispersion characterization of MWCNT surfaces suggest that the dominant effect of OH plasma on MWCNTs is reduced π-conjugated states due to creating structural defects and attachment of oxygen-containing functional groups. [Copyright &y& Elsevier]

Abstract: Multiwalled carbon nanotubes (MWCNTs) were treated with an atmospheric pressure plasma source using an argon/water mixture. Optical emission diagnostics has shown that hydroxyl radicals (OH) were the major reactive species in the plasma. The structural changes in MWCNTs were monitored by micro-Raman spectroscopy. The observed variation of the D and G band intensity ratio and position dispersion with plasma treatment time was ascribed to the change in structural disorder on MWCNT surfaces. Scanning electron microscopic study showed that some defects can be induced in MWCNTs during plasma treatment. Results of thermogravimetric analysis indicated that atmospheric pressure OH plasma is as effective as traditional wet methods for purifying MWCNTs. [Copyright &y& Elsevier]