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Nanopages
Authors: Elena Burakova, Alexandr Melezhyk, Alyona Gerasimova, Evgeny Galunin, Nariman Memetov, and Alexey Tkachev

In the present research, phenol-formaldehyde resins were used instead of common surfactants for dispersing carbon nanotubes and graphene nanoplatelets in order to develop new composite materials. The use of such resins makes it possible to increase the concentration of nanoparticles in solution by approximately two orders of magnitude. The presence of reactive groups on the surface of the phenol-formaldehyde-resin-modified carbonnanotubes and graphene nanoplatelets promotes synthesis of a variety of composites. According to the experiments performed herein, the modification of the nanomaterials with the phenol-formaldehyde resin significantly improves their compatibility and provides good water-solubility. While dispersing in water, the aggregates of the carbon nanotubes disappear, giving rise to an ordered structure. Besides, they form stable colloidal solutions at slightly alkaline pH values, but coagulate when decreasing the pH. This effect allows for self-assembly of carbon and composite nanostructures from nanoparticles in solution due to pH adjustment. This enables easy synthesis of hybrid composite materials based on carbon nanotubes, graphene nanoplatelets and phenol-formaldehyde resins.

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protection of the public against indoor exposure to radon (90/143/Euratom) Nagy É. H., Breitner D., Horváth Á., Szabó Cs. Study of a passive radon mitigation process and indoor radon concentration’s time dependence after

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Resolution and Discovery
Authors: Svetlana Jovanovic, Olaf C. Haenssler, Milica Budimir, Duška Kleut, Jovana Prekodravac, and Biljana Todorovic Markovic

into water (200 mL) and filtrated until the pH was 7. Chemical reduction of both GO and GQDs was conducted using in situ generated hydrogen [ 7 ]. Synthesized GQD and GO were dispersed in water in a concentration of 1 mg/mL and the ccHCl acid (35

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2008 Continuous monitoring of residual chlorine concentrations in response to controlled microbial intrusions in a laboratory-scale distribution system Water Research 42 3162

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bacterial cells were re-suspended in phosphate-buffered saline solution (PBS) and adjusted to the required concentration. Antibacterial activity experiments To assess the ability of K/rGO-CS matrix to capture and kill bacteria, each substrate was immersed in

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). The measurement conditions were an accelerating voltage of 30 kV with a beam diameter of 1 μm for a counting time of 60–120 s and a minimum detectable weight concentration ranging from 0.1 to 1 wt%. Physical separation treatment for Abu Rusheid

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to increase with high replacement level. Terrence [ 52 ] evaluated the efficacy of metakaolin in minimizing the expansion due to alkali-silica reaction (ASR). When HRM is used to replace up to 20% of OPC the alkali concentration of the pore solutions

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transducer surface for the PA probe with inclined elements. The obtained results have shown a high concentration of the ultrasound beam on the focal point direction with reduced effect of side lobes. Fig. 7. Dimensionless displacement amplitude over the

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International Review of Applied Sciences and Engineering
Authors: Adebayo Surajudeen Adekunle, Adekunle Akanni Adeleke, Peter Pelumi Ikubanni, Peter Olorunleke Omoniyi, Tajudeen Adelani Gbadamosi, and Jamiu Kolawole Odusote

–7 ]. Rapid quenching is required to circumvent unwanted concentration of alloying elements along the boundary structure grain. More so, failure not to quench faster than necessary in order to lessen residual stress can result into excessive cracking or

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comparison with other commercial fillers. He reported that the mechanical properties of the vulcanizates filled with rice husk ash were comparable to those filled with inert fillers. The influence of fibre length and concentration on the physical properties

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