•CdS QDs 3DOH ZnTiO3-ZnO-TiO2 composite was prepared by PS microspheres as the template.•The composite modified by CdS QDs has a good light absorption range.•Three-dimensional ordered hollow ...spherical structure enhances the charge transfer.•As-hollow structure offers more suitable transport channels for reactive molecules.•A rate of hydrogen evolution of CdS QDs 3DOH ZnTiO3-ZnO-TiO2 is 300 times of TiO2.
Three-dimensional ordered hollow spherical ZnTiO3-ZnO-TiO2 composite (3DOH ZnTiO3-ZnO-TiO2) was prepared by vacuum impregnation combined with calcination method using polystyrene (PS) colloidal microspheres as the template, and the CdS QDs were modified into 3DOH ZnTiO3-ZnO-TiO2 by water bath method. The crystal structure, chemical composition, surface morphology, optical absorption and surface physicochemical properties of CdS QDs modified 3DOH ZnTiO3-ZnO-TiO2 (CdS QDs 3DOH ZnTiO3-ZnO-TiO2) composite were well characterized. The results show that the three-dimensional ordered hollow spherical CdS QDs 3DOH ZnTiO3-ZnO-TiO2 composite mainly composes of anatase phase TiO2, rutile phase TiO2, and hexagonal phase ZnTiO3 and hexagonal phase ZnO. Among them, a homojunction is formed between the mixed crystal phase of TiO2 (anatase–rutile), and a heterojunction is found between hexagonal phase ZnTiO3 and hexagonal phase ZnO. In addition, the composite treated by the polystyrene (PS) colloidal microspheres template has formed the three-dimensional ordered hollow sphere structure, the hollow spheres are arranged neatly and orderly, and the sphere wall is formed by stacking nanoparticles. At the same time, the three-dimensional ordered hollow spherical structure of CdS QDs 3DOH ZnTiO3-ZnO-TiO2 composite provides more transfer paths for material transport and promotes repeated light absorption, prolonging the lifetime of photogenerated charge carriers. Moreover, due to the close connection between CdS QDs, ZnTiO3, ZnO and TiO2, the separation of electrons and hole pairs is facilitated, and the recombination of electron and hole pairs is effectively suppressed, so that CdS QDs 3DOH ZnTiO3-ZnO-TiO2 composite exhibits extremely high photocatalytic activity. Its hydrogen production is more than 300 times that of pure TiO2, moreover, of which cycle stability also shows better.
Inorganic and organic constituents present in textile effluents have a noticeable effect on the performance of Fenton processes. However, studies have been focused on simple wastewater matrices that ...do not offer enough information to stakeholders to evaluate their real potential in large-scale facilities. Chemical auxiliaries, commonly present in textile wastewaters (NaCl = 30 g/L, Na
2
CO
3
= 5 g/L, and CH
3
COONa = 1 g/L), affect both the economic and environmental performance of the process because they increase the treatment time (from 0.5 to 24 h) and the consumption of H
2
SO
4
(657%) and NaOH (148%) during conditioning steps. The life cycle assessment (LCA) performed with the IPCC-2013 method revealed that dyeing auxiliaries increase from 1.06 to 3.73 (252%) the emissions of carbon dioxide equivalent (CO
2
-Eqv/m
3
). Electricity consumption can be considered an environmental hotspot because it represents 60% of the carbon footprint of the Fenton process. Also, the presence of auxiliaries is critical for the process because it results in the increase of the relative impact (between 50 and 80%) in all environmental categories considered by the ReCiPe-2008 method. Chemical auxiliaries increased the costs of the treatment process in 178% (US$2.22/m
3
) due to the higher energy consumption and the additional reagent requirements. It is worthwhile mentioning that the technical simplicity of the Fenton process and its low economic and environmental costs turn this process into an attractive alternative for the treatment of textile effluents in emerging economies.
Vibrational relaxation of a single-component carbon dioxide in adiabatic thermal bath is studied in multi-temperature approaches using several models for the vibrational relaxation time. The energy ...production terms in two- and three-temperature vibrational energy relaxation equations are written in the frame of the common Landau-Teller model as well using corrections based on introducing multi-temperature relaxation times for various vibrational energy exchanges within and between CO2 modes. For the relaxation time evaluation, two theoretical models for the transition probabilities are implemented: the first-order perturbation theory and the forced harmonic oscillator model; several experimental data sets are also assessed. It is shown that the forced harmonic oscillator model provides satisfactory agreement with experimental relaxation times in a wide temperature range. Solutions obtained using the two theoretical models for the transition probabilities show essentially different trends, incubation time and relaxation rate.
Bioprinting is a biofabrication technology which allows efficient and large-scale manufacture of 3D cell culture systems. However, the available biomaterials for bioinks used in bioprinting are ...limited by their printability and biological functionality. Fabricated constructs are often homogeneous and have limited complexity in terms of current 3D cell culture systems comprising multiple cell types. Inspired by the phenomenon that hydrogels can exchange liquids under the infiltration action, infiltration-induced suspension bioprinting (IISBP), a novel printing technique based on a hyaluronic acid (HA) suspension system to modulate the properties of the printed scaffolds by infiltration action, was described in this study. HA served as a suspension system due to its shear-thinning and self-healing rheological properties, simplicity of preparation, reusability, and ease of adjustment to osmotic pressure. Changes in osmotic pressure were able to direct the swelling or shrinkage of 3D printed gelatin methacryloyl (GelMA)-based bioinks, enabling the regulation of physical properties such as fiber diameter, micromorphology, mechanical strength, and water absorption of 3D printed scaffolds. Human umbilical vein endothelial cells (HUVEC) were applied as a cell culture model and printed within cell-laden scaffolds at high resolution and cell viability with the IISBP technique. Herein, the IISBP technique had been realized as a reliable hydrogel-based bioprinting technique, which enabled facile modulation of 3D printed hydrogel scaffolds properties, being expected to meet the scaffolds requirements of a wide range of cell culture conditions to be utilized in bioprinting applications.
Nile tilapia, Oreochromis niloticus, is the most cultivated fish species in the world, due to its low cost, high growth rate, environmental adaptability, and resistance to disease and stress. ...Anesthetics for fish become necessary in management because they minimize mortality during transport and maintenance of ponds, one of the most used anesthetics is clove oil, which has eugenol as the major substance, representing 90–95 % of clove oil. The present study evaluates the effect of eugenol on cardiac activity in Oreochromis niloticus specimens and relates it to behavioral data to determine a concentration window for safe anesthesia. For the comportamental analysis, was used five treatments (50, 75, 100, 125, and 150 μL·L−1) were evaluated and for the eletrocardiographic test was used seven groups (Control, Vehicle, 50, 75, 100, 125, and 150 μL·L−1), n = 9/treatment, totaling 108 animals. Behavioral and electrocardiographic tests were performed on all treatments during induction and recovery. The results of the behavioral tests demonstrated the reversibility of the effects with recovery of the posture reflex, varying according to the concentration. The ECG results showed a slow recovery because, at concentrations above 100 μL·L−1, there was no full reversibility of the cardiac effects in the observed experiment time, which could cause greater changes in the tilapia hemodynamics, which led us to identify a window for safe anesthesia. Eugenol is an effective anesthetic in Nile tilapia juveniles when used in concentrations ranging from 50 to 100 μL·L−1, if there is a need for anesthetic deepening, doses above 100 μL·L−1, however, the animals must be monitored due to hemodynamic changes.
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•Eugenol is an effective anesthetic in Nile tilapia when used in a safe window of anesthetic concentration between 50 μL.L-1 to 100 μL.L-1;•The high doses of eugenol in tilapia can cause alterations in the hemodynamics of these animals, even after recovery;•The results suggest that eugenol has activity in cardiac tissue, independent of its central action;•High concentrations, there is desynchrony in the recovery of postural reflex and cardiac activity (sinus bradycardia);
Background There is insufficient evidence for daily chlorhexidine bathing to reduce nosocomial spread of carbapenem-resistant Acinetobacter baumannii (CRAB) in endemic situations. Methods An ...interrupted time series study was performed to evaluate the effect of daily chlorhexidine bathing on the acquisition of CRAB in a medical intensive care unit (ICU) with CRAB endemicity. There was a 14-month control period and 12-month chlorhexidine bathing period. Segmented Poisson regression analysis was performed to assess the impact of chlorhexidine bathing on the level and trend of the series of prevalence rates and incidence density. Also, chlorhexidine susceptibility testing was performed on CRAB isolates collected during the chlorhexidine bathing period. Results There was a 51.8% reduction of CRAB acquisition rates after an introduction of daily chlorhexidine bathing (44.0 vs 21.2 cases/1,000 at-risk patient days, P < .001). There was a significant reduction in the level (−0.604; 95% CI, −0.904 to −0.305; P < .001) of incidence density of CRAB, whereas there was no significant change in both level and trend of CRAB prevalence rates. Minimum inhibitory concentration of chlorhexidine against a total of 98 CRAB isolates ranged from 8-64 μg/mL. Conclusion Daily chlorhexidine bathing significantly reduces the acquisition of CRAB in a medical ICU with CRAB endemicity.
In this paper, we study the evaporation dynamics of the Sachdev-Ye-Kitaev model, with an initial temperature Tχ, by coupling it to a thermal bath with lower temperature Tψ < Tχ modeled by a larger ...SYK model. The coupling between the small system and the bath is turned on at time t = 0 . Then the system begins to evolve and finally becomes thermalized. Using the Keldysh approach, we analyze the relaxation process of the system for different temperatures and couplings. For marginal or irrelevant coupling, after a short-time energy absorption, we find a smooth thermalization of the small system where the energy relaxes before the system become thermalized. The relaxation rate of effective temperature is found to be bounded by T , while the energy thermalization rate increases without saturation when increasing the coupling strength. On the contrary, for the relevant coupling case, both energy and effective temperature show oscillations. We find this oscillations frequency to be coincident with the typical excitation energy of the small SYK system.
The diffusion mechanism of carbide-forming elements from a molten salt bath to a substrate surface was studied in this research, with particular focus on the processes occurring in the molten bath at ...the time of coating. Metal, oxide, and metal?oxide baths were investigated, and the coating process was performed on H13 steel substrates. Scanning electron microscopy and electron-probe microanalysis were used to study the coated samples and the quenched salt bath. The thickness of the carbide coating layer was 6.5 ± 0.5, 5.2 ± 0.5, or 5.7 ± 0.5μm depending on whether it was deposited in a metal, oxide, or metal?oxide bath, respectively. The phase distribution of vanadium-rich regions was 63%, 57%, and 74% of the total coating deposited in metal, oxide, and metal?oxide baths, respectively. The results obtained using the metal bath indicated that undissolved suspended metal particles deposited onto the substrate surface. Then, carbon subsequently diffused to the substrate surface and reacted with the metal particles to form the carbides. In the oxide bath, oxide powders dissolved in the bath with or without binding to the oxidative structure (Na2O) of borax; they were then reduced by aluminum and converted into metal particles. We concluded that, in the metal and oxide baths, the deposition of metal particles onto the sample surface is an important step in the formation of the coating.
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