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This paper aims to present the design and synthesis of a series of novel antibacterial monoazo disperse dyes based on sulfonamide derivatives to combine the dyeing and functional finishing steps on polyester into one process.

The diazoniom salts of sulfonamides, namely, 4-amino-N-(2-pyrimidinyl) benzenesulfonamide, 4-amino-N-(4-methyl-2-pyrimidinyl) benzenesulfonamide and 4-amino-N-(4,6-dimethyl-2-pyrimidinyl) benzenesulfonamide were prepared and then coupled to N,N-diethyl aniline, N,N-dicyanoethyl aniline and N,N-dihydroxy ethyl aniline, respectively, to produce the dyes.

The structures of the dyes were characterized using their spectral data (FTIR, 1H-NMR, UV-Vis) and elemental analysis. The results indicated that all the dyes exhibit positive solvatochromism in more polar solvents. Dispersion of the dyes was prepared in water and applied to polyester fabrics. The synthesized dye 3a which had good exhaustion on the fabric (89.98 per cent) and were tinctorially stronger (28899 l/mol.cm) showed higher visual colour yield (16.51). The antibacterial efficacy of the dyes was assessed, and they showed activity against both gram-positive and gram-negative bacteria but in different levels depending on their structures.

A simple way to combing functional finishing and dyeing in one process was successfully performed via design and synthesis of disperse dyes with an antibacterial moiety incorporated into dye molecules. The dyes were fully charaterized and evaluated on polyester.

A series of novel antibacterial monoazo disperse dyes based on sulfonamide derivatives were synthesized. The authors studied their application for dyeing of polyester fabric. The dyes offered good results in terms of preparation, yield, purity, visual colour yield, fastness properties and activity against bacteria.

The purpose of this paper is to investigate the relationship between internet filtering, emotions and information-seeking behaviour.

In total, 15 postgraduate students at an Iranian university participated in the study which involved a questionnaire, search tasks with think aloud narratives, and interviews.

Internet content filtering results in some changes in the information-seeking behaviour of users. Users who face website blocking use a variety of methods to bypass filtering, mostly by using anti-filter software. Filtering encourages users to use channels such as social networking services to share resources and it increases the use of library material by some of the users. Users who face filtering during their search are more likely to visit more pages of results and click on more hits in the results, unlike users who do not experience filtering who rarely go past the first page. Blocking users’ access to content stimulates their curiosity and they become more determined to access the content. In terms of the affective aspect, filtering causes several negative emotions (e.g. anger, disgust, sadness and anxiety) and the main reason for these emotions is not the inability to access information but the feeling of being controlled and not having freedom.

The study was limited to a small number of postgraduate students in social sciences and not generalisable to all user groups. The implication is that in countries where filtering is used, libraries can play an important role in serving users and reducing users negative emotions, especially if libraries can take advantage of technologies such as social media for their services.

This is first study to address the effects of internet filtering on information-seeking behaviour and emotions. The study shows that internet filtering causes negative emotions and results in some changes in information-seeking behaviour.