30 research outputs found

    Step by step procedures : degradation of polycyclic aromatic hydrocarbons in potable water using photo-Fenton oxidation process

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    Polycyclic aromatic hydrocarbons (PAHs) are carcinogenic compounds, composed of two or more fused benzene rings and abundantly found in mixed-use areas. Mixed-use areas consist of dense population, urbanization, industrial and agricultural activities. River pollution are common in mixed-use areas and 98% of Malaysia's fresh water supply originates from surface water. The biological degradation, adsorption and advanced oxidation process were documented as the available PAHs treatment for water. To date, the application of the photo-Fenton oxidation process has been reported for the treatment of PAHs from contaminated soil (review paper), landfill leachate, municipal solid waste leachate, sanitary landfill leachate, aniline wastewater, ammunition wastewater and saline aqueous solutions. As for potable water, the application of Fenton reagent was aided with photo treatment or electrolysis not focusing on PAHs removal. • The presented MethodsX was conducted for PAHs degradation analysis in potable water samples using photo-Fenton oxidation process. • The designed reactor for batch experiment is presented. • The batch experiment consists of parameters like concentration of 17 USEPA-PAHs in the prepared aqueous solution (fixed variable), reaction time, pH and molarity ratio of hydrogen peroxide (H2O2): ferrous sulfate (FeSO4)

    Managing globally distributed expertise with new competence management solutions: a big-science collaboration as a pilot case.

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    In today's global organisations and networks, a critical factor for effective innovation and project execution is appropriate competence and skills management. The challenges include selection of strategic competences, competence development, and leveraging the competences and skills to drive innovation and collaboration for shared goals. This paper presents a new industrial web-enabled competence management and networking solution and its implementation and piloting in a complex big-science environment of globally distributed competences

    Effect of Volcanic Ash and Natural Pozzolana on mechanical properties of sustainable cement concrete: A comprehensive review

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    Environmental degradation is on the rise due to escalating pollution caused by raw material depletion and the increasing demand for concrete products. Consequently, researchers and scientists have dedicated significant efforts towards developing sustainable, eco-friendly concrete using renewable materials. Among these materials, Volcanic Ash (VA) and other Natural Pozzolana (NP) types have emerged as promising Supplementary Cementitious Materials (SCMs). VA and NP types play a crucial role in reducing costs, energy consumption, and environmental impacts associated with cement production. Thus, it is imperative to investigate the characteristics of VA and NP and their influence on the performance of concrete and cement mortar. This paper presents a comprehensive review of previous studies examining the effect of VA and other NP types on the mechanical properties of concrete while evaluating their chemical, physical, and microstructure characteristics. The findings from these studies indicate that the properties of concrete primarily depend on the characteristics and quantities of NP employed. Notably, silica dioxide (SiO2) comprises the predominant component in VA compositions. In most cases, an increase in VA and NP content within concrete mixtures leads to a reduction in strength. Finally, recommendations and suggestions for future research are provided to enhance concrete properties and achieve the development of sustainable construction materials

    Purification, Characterization and Partial Amino Acid Sequencing of Two New Aspartic Proteinases from Fresh Flowers of Cynara cardunculus L.

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    Two new aspartic proteinases have been isolated from stigmas of the cardoon Cynara cardunculus L. by a two-step purification procedure including extraction at low pH, gel filtration on Superdex 200, and ion-exchange chromatography on Mono Q. To follow the conventional nomenclature for aspartic proteinases, we have named these proteinases cardosin A and cardosin B. On SDS/PAGE, cardosin A migrated as two bands with apparent molecular masses of 31 000 Da and 15000 Da where as the chains of cardosin B migrated as bands of 34000 Da and 14000 Da. The partial amino acid sequences of the two cardosins revealed that they are similar but not identical, and that they differ horn the previously reported cardoon proteinases named cynarases, which were assumed to be derived from a common precursor. Although the cardosins show some degree of similarity to each other, we could detect no immunological cross-reactivity between them. Both cardosins were active at low pH and were inhibited by pepstatin, with Ki values of 3 nM for cardosin A and 1 nM for cardosin B, indicating that they belong to the class of aspartic proteinases. Significant differences between the two enzymes were also found for the Kcat/Km values for the hydrolysis of two chromophoric synthetic peptides. The active-site ionization constants, pKe1 and pKe2, for cardosin A are 2.5±0.2 and 5.3±20.2, whereas for cardosin R they are 3.73±10.09 and 6.7±50.1. The results herein described on the structural and kinetic properties of the cardosins indicate that they are the products of distinct genes which have probably arisen by gene duplication. A scheme for the proteolytic processing of the two enzymes is also proposed
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