Glutaraldehyde-crosslinked alginate gel containing chitosan (AGCC) used for the removal of Hg 2þ ions from aqueous solutions. Three bead sizes were obtained and performed to study the uptake equilibrium and kinetics of Hg 2þ by AGCC (ca. an hour). The adsorption capacity was found to be independent of adsorbent particle size indicating that sorption occurs in the whole AGCC bead. A high initial rate of Hg 2þ uptake was followed by a slower uptake rate suggesting intraparticle diffusion as the rate-limiting step. The rate of Hg 2þ uptake increases with decreasing AGCC bead size. AGCC also enhanced the rate and the capacity of Hg 2þ adsorption. The maximum Hg 2þ adsorption capacity of AGCC was found 667 mg/g, which is over 20 times higher than that of alginate bead. Our results reveal the well-distributed chitosan powders in the alginate gel bead and Hg 2þ ions can reach inside the chitosan bead. It indicates the feasibility of using AGCC as metal adsorbent at low pH values, and allows the regeneration of adsorbent. Hg 2þ ions adsorbed on AGCC bead were desorbed effectively about 95% by H 2 SO 4 at the third cycle. The use of AGCC for the removal of Hg 2þ ions from the waste streams appears to be promising.

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Purpose The evolution of technology has become the mainstream of the current technological innovation era. Technological change is organized in its unique pattern and a new approach that takes place in a systematic and selective manner. Such change is generally molded with the amalgamation of various factors, namely, economic, social or scientific and technological. This paper aims to focus on identifying technological trajectories in a technological ecosystem with the case of m-payment technology. Design/methodology/approach This study constructs a patent citation network for mobile payment service technology through patent citation data and identifies the main evolution process using the main path analysis of the network. The scope of this study focuses on key innovation using social network analysis and patent citation network, validated using the case of a mobile payment system and analyzing its technological trajectory. Findings Analyzing technology evolution provides a greater insight of the overall technology landscape to the researcher and practitioner. Analyzing the m-payment technology landscape gives three main categories of m-payment systems: the mobile financial transaction system), the payee mobile device payment selection system and e-wallet services. Originality/value The novelty of this research lies in the process of identifying technological evolution using social network and patent citation network analysis. The case of m-payment technology ecosystem is studied quantitatively which is not explored by previous researchers. This research provides a way to develop the main path technology of innovative products or services to identify technology evolution using the case of m-payment landscape.

Abstract:The pure elements Ti, Zr, Cr, Nb were selected to produce an TiCrZrNb alloy target and deposited thin films thereof by a reactive high vacuum DC sputtering process. Nitrogen was used as the reactive gas to deposit the nitride thin films. The effect of nitriding on the properties of the TiCrZrNbN x film was tested by changing the nitrogen ratio of the atmosphere. All of the as-deposited TiCrZrNbN x nitride films exhibited an amorphous structure. The film thickness decreases by increasing the N 2 flow rate, because the Ar flow rate decreased and the target was poisoned by nitrogen. The hardness and Young's modulus were also measured by a nano-indenter. The hardness and Young's modulus of the TiCrZrNbN x nitride films were all lower than those of a TiCrZrNb metallic film.

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