New strategy for microplastic degradation: Green photocatalysis using a protein-based porous N-TiO2 semiconductor

Currently, the global community considers microplastics as a marine pollutant of emerging concern. To mitigate the oceanic microplastic pollution, it is necessary to reduce inputs from inland. In this sense, we present the first report on the use of photocatalysis for the degradation of HDPE microplastics extracted from a commercially available facial scrub. This was achieved by using two proposed semiconductors based on N-TiO₂. One was green synthesized using the extrapallial fluid of fresh blue mussels, which presented an excellent capacity to promote photocatalytic degradation in solid and aqueous environments; while the second photocatalyst, obtained from a conventional sol-gel synthesis, presented good capacity to promote mass loss of the as-extracted microplastics in an aqueous environment. Mass losses, SEM and FTIR analysis confirmed HDPE degradation. Results showed that environmental conditions, microplastics/N-TiO₂ interaction and the N-TiO₂ surface area should be carefully set and monitored in order of avoiding the arrest of photocatalysis.     

Synthesis of Crosslinked Copolymers based on Acrylonitrile Containing Carboxyl and Amidrazone Groups

Summary Chelating networks based on modified chemically acrylonitrile with hydrazine at alkaline solution were synthesized. The resin beads with different porosities were obtained by aqueous suspension copolymerization of acrylonitrile (AN) and divinylbenzene (DVB). The unmodified and modified resins were characterized by bulk density, surface area, average pore diameter, elemental analysis (CHN), FTIR, ¹³C CP/MAS NMR and scanning electronic microscopy. Elemental analyses were used to observe the increasing of nitrogen and oxygen contents due to chemical modification. Spectroscopic techniques (FTIR and ¹³C CP/MAS NMR) were employed to study the structural changes provoked by the modification with hydrazine. The contents of carboxyl and amidrazone group into the copolymer structure were dependent on the reaction conditions.     

The impact of clients’ decision-making on their adoption of industrialized building

Previous research has shown that client organizations’ decision-making about new-build creates individual-level and organizational-level barriers to the adoption of Swedish industrialized building (IB). However, it has been proposed that clients may overcome barriers on both levels by allowing multiple meanings and conflicting interpretations to surface and interact with their decision-making. The aim is to test this proposition. Based on the theoretical fields of decision-making and organizational information processing, a framework for analysis has been developed. In the framework, three decision-making approaches are operationalized: rational, judgments and managing multiple meanings. Data were collected using in-depth interviews with key decision-makers from four Swedish professional clients differing on when and if they adopted IB: one early-adopter, two late-adopters and one non-adopter. The empirical findings support the proposition and show a relationship between how clients manage multiple meanings in their decision-making and their adoption of IB. The research adds to the understanding of how clients may overcome barriers to the adoption of IB on both individual and organizational levels. Moreover, it increases understanding about how clients might better cope with radical changes and innovations.     

Book review

While risk and uncertainty management have received much attention within construction management research, management of information interpretation remains unexplored. Situations that are generally overlooked are those where increased amounts and flow of information are not the solution to the human problem of managing multiple meanings of information and conflicting interpretations, i.e. ‘equivocality’. The aim is to identify and differentiate between construction clients’ uncertainty and equivocality about industrialized construction in Sweden, and, in the light of those findings, to evaluate clients’ current information processing practice on investment decisions in new-build in order to assess and discuss clients’ ability to manage uncertainty and equivocality. Based on information processing theory, analysis of aggregated data from three previous studies shows that there is a need to manage both uncertainty and equivocality. At the same time, clients’ ability to do this is found to be limited. Consequently, when industrialized construction moves clients beyond their current frame of reference, clients’ information processing practice does not support decision making. It is also proposed that differentiating between uncertainty and equivocality will enable a more profound understanding of the sequential order for information processing, i.e. that one must define questions (reduce equivocality) before one can find answers to the questions (reduce uncertainty).     

Polyacrylamide-coated MCM-48 mesoporous silica spheres: synthesis,characterization and drug delivery study

Mesoporous type-MCM-48 silica was grafted with polyacrylamide (PAAm) by using an azo-type initiator. The effect of monomer and initiator concentrations, reaction time, and temperature were evaluated to determine the optimal grafting conditions. Functionalized MCM-48 silicas were characterized by X-ray diffraction (XRD), infrared spectroscopy, thermogravimetric analysis, nitrogen adsorption–desorption analyses, scanning electron microscopy (SEM) and transmission electron microscopy (TEM) which confirmed the grafting process. According to XRD, SEM and TEM results, PAAm-modified MCM-48 silica did not show changes in its morphology and mesostructure by comparing with pristine MCM-48. Also, modified silicas were tested as delivery system using nalidixic acid as drug model. MCM-48-PAAm silicas were able to load more significant amounts of nalidixic acid than the unmodified MCM-48, and showed a sustained delivery behaviour, releasing about 80% of drug.     

Influence of cobalt ferrite content on the structure and magnetic properties of (CoFe2O4)X (SiO2-PVA)100-X nanocomposites

(CoFe₂O₄)_X(SiO₂-PVA)_100-X (X = 5, 25, 50, 75 and 95%) nanocomposites were prepared via sol-gel route and annealed at 700 and 1100 °C. The influence of CoFe₂O₄ content on the structure, morphology and magnetic properties of nanocomposites was studied. X-ray diffraction patterns, Mössbauer and Fourier transform infrared spectra revealed the formation of CoFe₂O₄ as unique magnetic phase. The crystallinity degree increases with the CoFe₂O₄ content and the annealing temperature. Transmission electron microscopy images revealed the spherical shape of the obtained nanocomposites. Mössbauer spectra exhibit typical magnetic sextets, allowing the calculation of the cations distribution among tetrahedral and octahedral sites and the stoichiometry of CoFe₂O₄. A strong correlation between the particle morphology and the magnetic properties of nanocomposites was found. The highest saturation magnetization was identified for (CoFe₂O₄)₉₅(SiO₂-PVA)₅ nanocomposite.     

Subjective evaluation of natural high‐saturated images on a wide gamut display

In previous studies of image evaluation using wide color gamut displays, it is unclear to what degree people prefer the chroma‐varying images, especially the images that are more saturated than the most preferred image. Here, we present a study using a wide color gamut display, which measured viewers' most preferred level of image chroma (experiment 1) and their subjective evaluation of images that were less or more saturated than the previously most preferred one (experiment 2). The results showed that (a) the subjects' preferences for the original or for more saturated images depended on the images' original chroma and (b) the subjective evaluation of the images, that is, Valence and Arousal, did not deteriorate when the chroma of images increased more than the most preferred level. Such results indicate that the increase of the image chroma in wider color gamut displays can have a substantial influence on the impression images have on viewers.