Improved coloristic properties and high NIR reflectance of environment-friendly yellow pigments based on bismuth vanadate

Herein, fine powders of yellow pigments based on BiVO₄ were successfully prepared in two crystalline forms, tetragonal zircon-structured and monoclinic scheelite-structured, through a ethylene glycol-assisted method subjected to a thermal treatment at two different temperatures. The obtained materials were brightly colored with different hues of yellow, exhibited high reflection in the near-infrared region and showed visible luminescence under excitation by UV light. The new preparation method had a considerable effect on chromatic properties of the prepared scheelite-structured BiVO₄ pigments. The sample with the most vivid and bright shade of yellow was found to have the L^*a^*b^* and L^*C^*_ab h^*_ab color coordinates of (87.28, 0.37, 91.53) and (87.28, 91.53, 89.79), which are indicative of exceptionally good chromatic properties superior and/or comparable to those of other inorganic yellow pigments, both commercially available and recently described. In addition, the NIR reflectance of this powder was very high (≥?80%).     

The Absence of the AtSYT1 Function Elevates the Adverse Effect of Salt Stress on Photosynthesis in Arabidopsis

Arabidopsis thaliana SYNAPTOTAGMIN 1 (AtSYT1) was shown to be involved in responses to different environmental and biotic stresses. We investigated gas exchange and chlorophyll a fluorescence in Arabidopsis wild-type (WT, ecotype Col-0) and atsyt1 mutant plants irrigated for 48 h with 150 mM NaCl. We found that salt stress significantly decreases net photosynthetic assimilation, effective photochemical quantum yield of photosystem II (Φ_PSII), stomatal conductance and transpiration rate in both genotypes. Salt stress has a more severe impact on atsyt1 plants with increasing effect at higher illumination. Dark respiration, photochemical quenching (qP), non-photochemical quenching and Φ_PSII measured at 750 µmol m⁻² s⁻¹ photosynthetic photon flux density were significantly affected by salt in both genotypes. However, differences between mutant and WT plants were recorded only for qP and Φ_PSII. Decreased photosynthetic efficiency in atsyt1 under salt stress was accompanied by reduced chlorophyll and carotenoid and increased flavonol content in atsyt1 leaves. No differences in the abundance of key proteins participating in photosynthesis (except PsaC and PsbQ) and chlorophyll biosynthesis were found regardless of genotype or salt treatment. Microscopic analysis showed that irrigating plants with salt caused a partial closure of the stomata, and this effect was more pronounced in the mutant than in WT plants. The localization pattern of AtSYT1 was also altered by salt stress.     

Prospective scintillation electron detectors for S(T)EM based on garnet film scintillators

The performance of a scintillation electron detector for a scanning electron microscope and/or a scanning transmission electron microscope (S(T)EM) based on new epitaxial garnet film scintillators was explored. The LuGAGG:Ce and LuGAGG:Ce,Mg film scintillators with chemical formula (Ce_0.01Lu_0.27Gd_0.74)_3–wMg_w(Ga_2.48Al_2.46)O₁₂ were prepared and their cathodoluminescence (CL) and optical properties were studied and compared with the properties of current standard bulk single crystal YAG:Ce and YAP:Ce scintillators. More specifically, CL decay characteristics, CL emission spectra, CL intensities, optical absorption coefficients, and the refractive indices of the mentioned scintillators were measured. Furthermore, electron interaction volumes with absorbed energy distributions, photomultiplier (PMT) photocathode matchings, modulation transfer functions (MTF), and the photon transport efficiencies of scintillation detectors with the mentioned scintillators were calculated. A CL decay time for the LuGAGG:Ce,Mg film scintillator as low as 28 ns with an afterglow of only 0.02% at 1 μs after the e‐beam excitation was observed. As determined from calculated MTFs, the scintillation detectors with the new film scintillators lose contrast transfer ability above 0.6 lp/pixel, while the currently commonly used YAG:Ce single crystal scintillators already do so above 0.1 lp/pixel. It was also calculated that the new studied film scintillators have an 8% higher photon transfer efficiency, even for a simple disk shape compared with the standard bulk single crystal YAG:Ce scintillator. The studied LuGAGG:Ce,Mg epitaxial garnet film scintillators were evaluated as prospective fast scintillators for electron detectors, not only in S(T)EM but also in other e‐beam devices.     

Determination of permeability and inertial resistance coefficient of filter inserts used in the cleaning of natural gas

The article describes a methodology for determination of permeability and inertial resistance coefficient of filter inserts used for the separation of solid and liquid impurities in natural gas. The parameters of the filter inserts are described by analytical relations and their real values are obtained experimentally. The realized experiment was focused on the measurement of the pressure drop in the insert, with which both permeability and inertial resistance coefficient were possible to be expressed. The experiment was performed on the reduced physical model of the filter separator, which was constructed at a scale of 1:127. During the experimental measuring the working medium was pressure air. In a real filter separator there is compressed natural gas used as the working medium. The reduced model, therefore, had to meet the basic requirement of similarity of flowing in the model and the real object, which was based on equality of the Reynolds criteria for the work and the model.     

Structure Formation in Tailor-Made Buriti Oil Emulsion During Simulated Digestion (Adv. Funct. Mater. 49/2023)

Functional food emulsions enriched in health-promoting nutrients can help to maintain and improve health and lifestyle. The oil extracted from the Amazonian buriti fruit is renowned for its high levels of carotenoid, vitamin E, and unsaturated fatty acids, which have been linked to improvements in cardiometabolic health. Here, buriti oil in water emulsions are developed and their colloidal transformations are investigated in an advanced digestion model with oral, gastric, and intestinal parts with in situ synchrotron small-angle X-ray scattering, cryogenic electron microscopy, and dynamic light scattering under simulated “healthy” and “compromised” digestive conditions. The interior oil phase of whey-stabilized buriti oil-in-water emulsion transforms into highly ordered lyotropic liquid crystalline structures during simulated intestinal digestion at compromised bile conditions. Simulated gastric digestion influences intestinal digestion by slowing it down, resulting in less ordered structures. The digestion-triggered structure formation is pH- and bile salt-dependent and can be modulated by adding vitamin E to the oil. This tailoring of structures during digestion offers a new pathway to steer digestion kinetics and nutrient bioavailability.     

Customized daltonization: adaptation of different image types for observers with different severities of color vision deficiencies

Universal Access in the Information Society - The color vision deficiency, popularly called daltonism or color-blindness, manifests with limited color discrimination ranging from slightly reduced...     

Grain Coarsening of Columnar Iron Polycrystals by Repetitive Cold Work and Annealing

Metallurgical and Materials Transactions A - Experimental studies on single crystals of pure metals are essential for understanding the mechanisms governing their plastic deformation as well as for...     

Porous silicon nitride–based drug delivery carrier

Tetracalcium phosphate/monetite biocement was modified with the addition of 30 wt% highly porous silicon nitride/α-tricalcium phosphate (α-TCP) microgranules. The volume ratio of Si₃N₄ and α-TCP in microgranules was 1:1 and showed good in vitro simulated body fluid bioactivity with precipitation of hydroxyapatite particles. The intention of addition of microgranules to the biocement was to have a carrier of drug, which can be released into the body in due time. Granules prepared by the freeze granulation of starting mixture of silicon nitride and calcium phosphate and subsequent sintering at 1100°C have a suitable pore structure for the foreseen use. The pore volume was almost 1000 mm³/g with the open porosity of 77 vol%. This porosity and the biocompatible composition of silicon nitride–based granules gave a chance to fabricate a suitable composite cement for dexamethasone (DMZ) drug release into the human body. An accelerated release of dexamethasone from composite cement was observed and the full amount of DMZ was released from the composite biocement after 10 days. The presented results are a good base to adjust the total drug release time by the mixing of an appropriate amount of drug infiltrated ceramic granules with the tetracalcium phosphate/monetite cement.     

Hierarchically Porous Bio-Based Sustainable Conjugate Sponge for Highly Selective Oil/Organic Solvent Absorption

This paper describes a novel conjugate biodegradable sponge based on the tree gum kondagogu with excellent selective oil/organic solvent absorption ability. The conjugate sponge is made hydrophobic (water contact angle 133°) by post-process vapor phase silylation, has porosity of ≈94% with very low density (18.4 mg cm⁻³). The sponge can absorb selectively up to 19–43 times its weight of oils and organic solvents. Meanwhile, good reusability is also observed in up to at least 10 cycles. The biodegradation behavior is studied from BOD (biological oxygen demand) analysis, where the non-silylated and silylated sponges degraded over 28 days by 92% and 76%, respectively, in waste-water sludge. The novel conjugate bio-based and biodegradable sponge used in this study is a promising sustainable material for clearing oil spills and for water treatment.