22 research outputs found

    Tungsten Catalysts for Visible Light Driven Ofloxacin Photocatalytic Degradation and Hydrogen Production

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    Some tungsten catalysts of interest that are synthesized are bismuth tungstate (BT) and Tetrabutylammonium decatungstate (TBADT), using two consolidated procedures. BT is used as a photo-catalyst for the simulated solar light degradation of ofloxacin (OFL) antibiotic under relevant real conditions (µg L−1, fresh water) with the limit of 0.05 g L−1 of catalyst. A quantitative drug decomposition occurred following a bi-exponential first-order law, with an efficiency comparable with the most used P25 TiO2 catalyst. The photocatalytic profiles of OFL at µg L−1 and mg L−1 were monitored by high-pressure liquid chromatography (HPLC) coupled with fluorescence (FD) and ultraviolet (UV) detectors. Additionally, the main photoproducts were identified by high-pressure liquid chromatography coupled to electrospray ionization in tandem with mass spectrometry (HPLC-ESI-MS/MS). The catalyst Tetrabutylammonium decatungstate (TBADT) was used as a catalyst to produce hydrogen from glucose and 2-propanol in aqueous solution, providing hydrogen gas evolution up to 10 µmol g−1 h−1

    Computational Study of the Stability of Natural Amino Acid isomers

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    The secular debate on the origin of life on our planet represents one of the open challenges for the scientific community. In this endeavour, chemistry has a pivotal role in disclosing novel scenarios that allow us to understand how the formation of simple organic molecules would be possible in the early primitive geological ages of Earth. Amino acids play a crucial role in biological processes. They are known to be formed in experiments simulating primitive conditions and were found in meteoric samples retrieved throughout the years. Understanding their formation is a key step for prebiotic chemistry. Following this reasoning, we performed a computational investigation over 100′000 structural isomers of natural amino acids. The results we have found suggest that natural amino acids are among the most thermodynamically stable structures and, therefore, one of the most probable ones to be synthesised among their possible isomers

    Computational Study of the Stability of Natural Amino Acid isomers

    Get PDF
    The secular debate on the origin of life on our planet represents one of the open challenges for the scientific community. In this endeavour, chemistry has a pivotal role in disclosing novel scenarios that allow us to understand how the formation of simple organic molecules would be possible in the early primitive geological ages of Earth. Amino acids play a crucial role in biological processes. They are known to be formed in experiments simulating primitive conditions and were found in meteoric samples retrieved throughout the years. Understanding their formation is a key step for prebiotic chemistry. Following this reasoning, we performed a computational investigation over 100′000 structural isomers of natural amino acids. The results we have found suggest that natural amino acids are among the most thermodynamically stable structures and, therefore, one of the most probable ones to be synthesised among their possible isomers.</p

    Pre-impregnation approach to encapsulate radioactive liquid organic waste in geopolymer

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    The pre-disposal management of Radioactive Liquid Organic Waste (RLOW) is hampered by its challenging physico-chemical properties. In this work, a straightforward conditioning option based on RLOW impregnation on absorbing materials and followed by encapsulation in a stable geopolymeric matrix is proposed, avoiding onerous pre-treatments and the use of surfactants. Recycled materials have been investigated as adsorbent and geopolymer precursors to foster process sustainability. Relevant properties have been studied to ascertain the waste acceptance criteria accomplishment: materials compatibility, RLOW loading factor and bleeding, microstructure, compressive strength, leaching and thermal stability. This approach is promising, although some criticalities remain unsolved

    Preparation of Catalysts from Renewable and Waste Materials

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    Research in the field of renewable, non-polluting energy sources is a current trend because of the need to replace fossil fuels due to socioeconomic issues and pollution by carbon&ndash;oxygen derivatives [...

    Protective textiles from the past and for the modern age

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    Our skin is a delicate environment. Temperature, humidity, UV rays, and other factors might induce unwanted alterations leading first to discomfort and later to skin alteration. For this reason, men always spent time and effort creating new technologies for textiles. Nowadays, protective textiles are well integrated having access to many materials and technologies, including a possible future where textiles are smart and, thanks to their sensors and actuators, can have an active protection. Nevertheless, modernity means use of high amount of natural resources and, in the context of sustainability, we might need to check back to our past and consider again old fibers, like Spanish Broom or Nettle

    Shortest Path Routing in Solar Powered WSNs Using Soft Computing Techniques

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    23-27The main objective of this paper is to develop a three phase genetic algorithm to find the shortest path routing in solar poweredWireless Sensor Networks (WSNs), and thereby reducing the energy loss and the time consumed in the communication between various nodes (sensors) of the same. A three phase hybrid genetic algorithm is proposed for solving the shortest Path (SP) routing problem. The performance of the proposed algorithm is compared with Dijkstra, Munemoto, and Ahn algorithms. Here we have classified the wireless sensors as clusters which uses k-means clustering algorithm and within each cluster the shortest path routing for communication is found out using proposed three phase genetic algorithms

    Tungsten Catalysts for Visible Light Driven Ofloxacin Photocatalytic Degradation and Hydrogen Production

    No full text
    Some tungsten catalysts of interest that are synthesized are bismuth tungstate (BT) and Tetrabutylammonium decatungstate (TBADT), using two consolidated procedures. BT is used as a photo-catalyst for the simulated solar light degradation of ofloxacin (OFL) antibiotic under relevant real conditions (&micro;g L&minus;1, fresh water) with the limit of 0.05 g L&minus;1 of catalyst. A quantitative drug decomposition occurred following a bi-exponential first-order law, with an efficiency comparable with the most used P25 TiO2 catalyst. The photocatalytic profiles of OFL at &micro;g L&minus;1 and mg L&minus;1 were monitored by high-pressure liquid chromatography (HPLC) coupled with fluorescence (FD) and ultraviolet (UV) detectors. Additionally, the main photoproducts were identified by high-pressure liquid chromatography coupled to electrospray ionization in tandem with mass spectrometry (HPLC-ESI-MS/MS). The catalyst Tetrabutylammonium decatungstate (TBADT) was used as a catalyst to produce hydrogen from glucose and 2-propanol in aqueous solution, providing hydrogen gas evolution up to 10 &micro;mol g&minus;1 h&minus;1

    Carbon dioxide photoreduction in prebiotic environments

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    The reduction of carbon dioxide is one of the hottest topics due to the concern of global warming. Carbon dioxide reduction is also an essential step for life's origins as photoautotrophs arose soon after Earth formation. Both the topics are of high general interest, and possibly, there could be a fruitful cross-fertilization of the two fields. Herein, we selected and collected papers related to photoreduction of carbon dioxide using compounds easily available on the Earth and considered of prebiotic relevance. This work might be useful also to scientists interested in carbon dioxide photoreduction and/or to have an overview of the techniques available
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