Peak Intensity Research Articles

Enhancing salt-induced gelation of egg yolk granules through pH-ultrasound combined treatment: A physicochemical and microstructural analysis

Salted duck eggs are a popular food product, but their high salt content and uneven salt distribution can reduce acceptability. This study investigated the effects of pH-high-intensity ultrasound combined treatment on the salt-induced gelation properties of egg yolk granules. The results showed that the pH5 + 150 W treatment group exhibited the best physical and gelation properties, with the smallest particle size (1597.33 nm), optimal dispersibility (PDI 0.29), and good stability. The gelation properties of this group also demonstrated excellent springiness (0.30 mm), cohesiveness (0.56), and gumminess (0.05 N). Furthermore, the pH5 + 150 W group had the highest water holding capacity of 97.42 % and relatively high hydrophobicity (173.39 μg). Notably, it also showed high oil exudation (2.83 %) and good sandiness (62.07 %). The pH5 + 150 W led to a significant redshift of the fluorescence peak at 335 nm and an enhancement of the peak intensity at 562 nm compared to the control group. Structural characterization revealed a more ordered protein structure and a uniform gel structure with enhanced electrostatic repulsion between oil droplets. Secondary structure analysis of the proteins showed a significant reduction in α-helix and β-sheet, while β-turn and random coil increased. In summary, the pH5 + 150 W treatment displayed the best gelation properties, providing theoretical guidance for enhancing the processing performance of yolk and expanding their application in the food industry.

The massive 2016 marine heatwave in the Southwest Pacific: An "El Niño-Madden-Julian Oscillation" compound event.

El Niño typically induces cooling in the Southwest Pacific Ocean during austral summers, usually leading to decreased marine heatwave frequency and severity. However, the 2016 extreme El Niño unexpectedly coincided with the longest and most extensive marine heatwave ever recorded in the region. This heatwave, spanning over 1.7 million square kilometers, persisting for 24 days with a peak intensity of 1.5°C, resulted in massive coral bleaching and fish mortality. This exceptional warming resulted from anomalously strong shortwave radiation and reduced heat loss via latent heat fluxes, owing to low wind speed and increased air humidity. These anomalies are attributed to a rare combined event "Madden-Julian Oscillation and extreme El Niño." Following 10 February, the rapid dissipation of this marine heatwave results from the most intense cyclone ever recorded in the South Pacific. The hazardous ecological impacts of this extreme event highlight the needs for improving our understanding of marine heatwave-driving mechanisms that may result in better seasonal predictions.

Low-cost fabrication methods of ZnO nanorods and their physical and photoelectrochemical properties for optoelectronic applications

Zinc Oxide (ZnO) nanorods have great potential in several applications including gas sensors, light-emitting diodes, and solar cells because of their unique properties. Here, three low cost and ecofriendly techniques were used to produce ZnO nanorods on FTO substrates: hydrothermal, chemical bath deposition (CBD), and electrochemical deposition (ECD). This study explores the impact of such methods on the optical, structural, electrical, morphological, and photoelectrochemical properties of nanorods using various measurements. XRD analysis confirmed the hexagonal wurtzite structure of ZnO nanorods in all three methods, with hydrothermal showing a preferred orientation (002) and CBD and ECD samples showing multiple growth directions, with average particle sizes of 31 nm, 34 nm, and 33 nm, respectively. Raman spectra revealed hexagonal Wurtzite structure of ZnO, with hydrothermal method exhibiting higher E2 (high) peak at 438 cm−1 than CBD and ECD methods. SEM results revealed hexagonal ZnO nanorods became more regular and thicker for the hydrothermal method, while CBD and ECD led to less uniform with voids. UV-vis spectra showed absorption lines between 390 nm and 360 nm. Optical bandgap energies were calculated as 3.32 eV, 3.22 eV, and 3.23 eV for hydrothermal, CBD, and ECD samples, respectively. PL spectra revealed UV emission band with a small intensity peak around 389 nm and visible emission peaks at 580 nm. Temperature dependent PL measurements for ZnO nanorods indicated that the intensities ratio between bound exciton and free exciton decreases with temperature increases for the three methods. Photocurrent measurements revealed ZnO nanorod films as n-type semiconductors, with photocurrent values of 2.25 µA, 0.28 µA, and 0.3 µA for hydrothermal, CBD, and ECD samples, and photosensitivity values of 8.01, 2.79, and 3.56 respectively. Our results suggest that the hydrothermal method is the most effective approach for fabricating high-quality ZnO nanorods for optoelectronic applications.

Investigation geographic origin of Laurus nobilis L. leaves using FTIR, SEM-EDX, and XRD analysis

Laurus nobilis L. is a polypragmatic plant with high added value. Leaves collected from different regions in the natural state without breeding have different economic values. In this study, the Geographic Origin and Altitude Effects of Laurus nobilis L. leave samples collected from provinces close to each other were investigated. For this purpose, SEM–EDS was used for morphological characterization of leaves, XRD was used for the characterization of inorganic components and FTIR-ATR was used for the identification of functional groups. By SEM analysis in the samples from Zonguldak region, significant differences were observed in the density of trichomes and glandular plumes more dense and also morphological cell sizes were found to be more large then Kastamonu region. In XRD plot, besides the amorphous state, it has seen that the crystal structure is also present in the structure. The effect of different altitudes on the FTIR spectra of the samples collected according to the provinces was also examined, and no significant difference was observed in the peak positions and intensities in the spectra according to the altitudes. Score plot on ranges of 2800–3000 cm-1 and 750–1800 cm−1 allowed origin of the Laurus nobilis L. discrimination. In order to analysis and classify them according to their geographical origin, FTIR data were combined with chemometric methods using PCA and discriminant analysis. PCA analysis explained 88.7% of the variance in the model. When the results of the discriminant analysis were evaluated, 56 of the 72 samples were classified correctly and 77.8% success was achieved. Both analysis showed that there are differences in the response of the same plant species to their presence in different origins. As a result, FTIR analysis allowed possibility the discrimination of Laurus nobilis L. leaves and in this way it is thought to discriminate of examples for other areas.

Influence of NH3 flow rate on the photoelectric properties of high Al content p-AlGaN.

High Al content (60%) p-AlGaN with different NH3 flow rates was grown using metal-organic chemical vapor deposition (MOCVD), and changes in its photoelectric properties were studied using the Hall effect tester (Hall) and cathodoluminescence (CL) spectrometer. The results show that the film resistivity increases from 3.8 Ω·cm to 46.5 Ω·cm with increasing NH3 flow rate. The impurity peak intensity of p-AlGaN grown under high NH3 flow conditions is particularly high, indicating numerous point defects. The results of high-angle annular dark-field scanning transmission electron microscopy (HAADF-STEM) show a large number of Ga interstitial atoms (Gai) at the interface. As Gai acts as a donor, this may be the main reason for the increase in resistivity. And under high NH3 flow conditions, a lattice distortion and a high density of dislocation occur between p-AlGaN and p-GaN, which can lead to enhanced carrier scattering and decreased mobility. Additional validation via LED growth experiments indicates that the luminescence intensity of samples with low ammonia concentration increased by more than 13000 times.

Digital platform work reinforcing performativity: teacher responses to work intensification explored through trace ethnography

ABSTRACT This paper critically explores how teachers’ everyday work is reconfigured through work on and around different digital platforms. In particular, it demonstrates teacher experiences of workload and work intensification and the different workarounds and adaptions to platforms done by teachers, conditioned by demands of performativity, e.g. discourses of optimising work, making visible and caring for school performances as part of a market-competitive and increasingly digitalised school system. By ethnographically tracing the digital work of six teachers in public and private upper-secondary schools through logs, follow-up interviews, observations and digital ‘go-alongs’, we show how central tasks, administration, communication and teaching are reconfigured through the distribution of work onto local-domestic and global platforms and relatively local school and national regulations. Our contribution to the discussion on platforms in education is how platforms and aligning devices and procedures reinforce performativity demands in teacher work. This reconfiguration produces tensions, interruptions and intensity peaks, often seen as work-time conflicts, but which nonetheless relate to wider, critical issues of the changing nature of teacher digital work being established in relation to the marketised and highly digitalised school.

Fluorescence detection of superoxide anion with CsPbBr3 perovskite quantum dots in aqueous media

Among reactive oxygen species, the superoxide radical anion (O2−) is of particular interest due to its involvement in oxidative stress-related diseases and environmental pollutants. Through solution-phase strategy mediated by ligands, colloidal spherical and water-stable perovskite quantum dots (PQDs) of cesium lead bromide (CsPbBr3) were fabricated by functionalizing with D-tartaric acid (D-TA) (namely, CsPbBr3@D-TA PQDs), exhibiting exceptional photoluminescence quantum yield of 29.88 % and intense emission peak at 522 nm when excited at 380 nm. The as-fabricated CsPbBr3@D-TA PQDs showed strong durability and displayed bright green fluorescence when exposed to 365 nm UV radiation. The emission peak of CsPbBr3 PQDs at 522 nm was completely quenched by O2−, showing wider linear range from 0.125 to 25 µM with a detection limit of 39.82 nM. Moreover, CsPbBr3@D-TA PQDs were also applied for bio-imaging of yeast cells. The CsPbBr3@D-TA PQDs-based fluorescence approach holds great potential for sensing of O2− in real samples.

A Preliminary Experimental Study on Biodegradation of 3D-Printed Samples from Biomass–Fungi Composite Materials

Products made from petroleum-derived plastic materials are linked to many environmental problems, such as greenhouse gas emissions and plastic pollution. It is desirable to manufacture products from environmentally friendly materials instead of petroleum-based plastic materials. Products made from biomass–fungi composite materials are biodegradable and can be utilized for packaging, construction, and furniture. In biomass–fungi composite materials, biomass particles (derived from agricultural wastes) serve as the substrate, and the fungal hyphae network binds the biomass particles together. There are many reported studies on the 3D printing of biomass–fungi composite materials. However, there are no reported studies on the biodegradation of 3D-printed samples from biomass–fungi composite materials. In this study, two types of biomass materials were used to prepare printable mixture hemp hurd and beechwood sawdust. The fungi strain used was Trametes versicolor. Extrusion based 3D printing was used to print samples. 3D-printed samples were left for five days to allow fungi to grow. The samples were then dried in an oven for 4 h at 120 °C to kill all the fungi in the samples. The samples were buried in the soil using a mesh bag and kept in an environmental chamber at 25 °C with a relative humidity of 48%. The weight of these samples was measured every week over a period of three months. During the testing period, the hemp hurd test samples lost about 33% of their original weight, whereas the beechwood sawdust samples lost about 30% of their original weight. The SEM (scanning electron microscope) micrographs showed the presence of zygospores in the test samples, providing evidence of biodegradation of the test samples in the soils. Additionally, the difference in peak intensity between the control samples and test samples (for both hemp hurd and beechwood sawdust) showed additional evidence of biodegradation of the test samples in the soils.

The Impact of Combined Chemotherapy and Intra-Tumoural Injection of Phosphorus-32 Microparticles on Vascularity in Locally Advanced Pancreatic Carcinoma.

Poor intra-tumoural vascularity contributes to a lack of response to chemotherapy in pancreatic cancers. Preliminary data suggest that the addition of endoscopic ultrasound (EUS)-guided intra-tumoural injection of phosphorus-32 (32P) microparticles to standard chemotherapy is potentially beneficial in locally advanced pancreatic cancer (LAPC). We aimed to assess changes in pancreatic tumour vascularity following 32P implantation, using contrast-enhanced EUS (CE-EUS). This was a prospective single-centre trial from January 2022 to 2024 of patients with unresectable, non-metastatic LAPC undergoing standard FOLFIRINOX chemotherapy and 32P implantation. We performed CE-EUS pre-implantation after two chemotherapy cycles and 4 and 12 weeks after implantation. Time-intensity curves were analysed for 90 s after IV contrast bolus to ascertain peak intensity and intensity gain. A total of 20 patients underwent 32P implantation, with 15 completing 12-week follow-up. The technical success of 32P implantation was 100%. The median primary tumour size reduced from 32 mm (IQR 27.5-38.75) pre-implantation to 24 mm (IQR 16-26) 12 weeks post-implantation (p < 0.001). Five patients (25%) had tumour downstaging, and four underwent resections. The baseline (pre-implantation, post-chemotherapy) median intensity gain of contrast enhancement within the tumour was 32.15 (IQR 18.08-54.35). This increased to 46.85 (IQR 35.05-76.6; p = 0.007) and 66.3 (IQR 54.7-76.3; p = 0.001) at 4 weeks and 12 weeks post-implantation, respectively. Over a median follow-up of 11.2 months (IQR 7.8-12.8), 15/20 (75%) of patients remained alive, with 3/20 (15%) demonstrating local disease progression. Overall survival was not significantly different between patients with or without an increased intensity of 10 a.u. or more at 12 weeks post-implantation. This is the first clinical study to demonstrate treatment-induced increased vascularity within pancreatic primary tumours, which followed 32P implantation and FOLFIRINOX chemotherapy. Larger comparative trials are warranted.

Magnetic field-engineered optical nonlinearity in germanene nanotubes

Abstract The linear and nonlinear optical properties of germanene nanotubes (GeNTs) under the influence of magnetic fields are investigated through theoretical analysis. By employing a tight-binding model beyond the Dirac cone approximation, the electronic band structure, density of states, dipole matrix elements, and third-order nonlinear optical susceptibilities are calculated. The application of a magnetic field induces a Zeeman splitting of the energy levels, breaking the band degeneracy. Consequently, the dipole matrix elements exhibit a magnetic field dependence, altering the intensity and number of allowed transitions. In the infrared and ultraviolet energy regions, the linear optical absorption spectrum displays the splitting of peaks into dual neighboring peaks, with the splitting distance linearly dependent on the magnetic field strength. The third-order nonlinear optical susceptibilities, χTHG(3)3ω and χIDIR(3)ω, reveal the emergence of multiple resonance peaks in different energy regions due to two-photon and three-photon absorption processes. The magnetic field significantly influences the number, position, and height of these optical peaks, enabling effective control over the nonlinear optical response. By investigating the scaled energy (E/E_g) dependence, a universal behavior is observed for the three- and two photon resonance peaks, where their positions remain constant, but their peak intensities are significantly enhanced under the influence of the magnetic field. These findings demonstrate the potential of GeNTs as tunable nonlinear optical materials, with the magnetic field serving as an effective parameter for engineering their optical properties for various applications in optoelectronics, photonics, and related fields.&amp;#xD;

Surging compound drought–heatwaves underrated in global soils

Compound drought-heatwaves (CDHWs) accelerate the warming and drying of soils, triggering soil compound drought-heatwaves (SCDHWs) that jeopardize the health of soil ecosystems. Nevertheless, the behavior of these events worldwide and their responses to climatic warming are underexplored. Here, we show a global escalation in the frequency, duration, peak intensity, and severity of SCDHWs, as well as an increase in affected land area, from 1980 to 2023. The increasing trends, which are particularly prominent since the early 2000 s, and projected to persist throughout this century, are dominated by summertime SCDHWs and enhanced by El Niño. Intensive soil warming as well as climatologically lower soil temperatures compared to air temperatures lead to localized hotspots of escalating SCDHW severity in northern high latitudes, while prolonged duration causes such hotspots in northern South America. Transformation of natural ecosystems, particularly forests and wetlands, to cropland as well as forest degradation substantially enhance the strength of SCDHWs. Global SCDHWs consistently exhibit higher frequencies, longer durations, greater severities, and faster growth rates than CDHWs in all aspects from 1980 to 2023. They are undergoing a critical transition, with droughts replacing heatwaves as the primary constraint. We emphasize the significant intensification of SCDHWs in northern high latitudes as well as the prolonged duration of SCDHWs in the Southern Hemisphere, posing an underrated threat to achieving carbon neutrality and food security goals.

The effect of plasma activated water on antimicrobial activity of silver nanoparticles biosynthesized by cyanobacterium Alborzia kermanshahica

BackgroundSilver nanoparticles are extensively researched for their antimicrobial properties. Cold atmospheric plasma, containing reactive oxygen and nitrogen species, is increasingly used for disinfecting microbes, wound healing, and cancer treatment. Therefore, this study examined the effect of water activated by dielectric barrier discharge (DBD) plasma and gliding arc discharge plasma on the antimicrobial activity of silver nanoparticles from Alborzia kermanshahica.MethodsSilver nanoparticles were synthesized using the boiling method, as well as biomass from Alborzia kermanshahica extract grown in water activated by DBD and GA plasma. The physicochemical properties of the synthesized nanoparticles were evaluated using UV-vis spectroscopy, Fourier-transform infrared (FTIR) spectroscopy, dynamic light scattering (DLS), zeta potential analysis, transmission electron microscopy (TEM), and gas chromatography-mass spectrometry (GC-MS) analysis. Additionally, the disk diffusion method was used to assess the antimicrobial efficacy of the manufactured nanoparticles against both Gram-positive and Gram-negative bacteria.ResultsThe spectroscopy results verified the presence of silver nanoparticles, indicating their biosynthesis. The highest amount of absorption (1.049) belonged to the nanoparticles synthesized by boiling under GA plasma conditions. Comparing the FTIR spectra of the plasma-treated samples with DBD and GA revealed that the DBD-treated samples had more intense peaks, indicating that the DBD method proved to be more effective in enhancing the functional groups on the silver nanoparticles. The DLS results revealed that the boiling method synthesized silver nanoparticles under DBD plasma treatment had a smaller particle size (149.89 nm) with a PDI of 0.251 compared to the GA method, and the DBD method produced nanoparticles with a higher zeta potential (27.7 mV) than the GA method, indicating greater stability of the biosynthesized nanoparticles. Moreover, the highest antimicrobial properties against E. coli (14.333 ± 0.47 mm) were found in the DBD-treated nanoparticles. TEM tests confirmed that spherical nanoparticles attacked the E. coli bacterial membrane, causing cell membrane destruction and cell death. The GC-MS results showed that compounds like 2-methylfuran, 3-methylbutanal, 2-methylbutanal, 3-hydroxy-2-butanone, benzaldehyde, 2-phenylethanol, and 3-octen-2-ol were much higher in the samples that were treated with DBD compared to the samples that were treated with GA plasma.ConclusionThe research indicated that DBD plasma was more efficient than GA plasma in boosting the antimicrobial characteristics of nanoparticles. These results might be a cornerstone for future advancements in utilizing cold plasma to create nanoparticles with enhanced antimicrobial properties.

BIM-based parametric energy analysis of green building components for the roofs and facades

Buildings are distinguished by their high energy demand over their lifespan. Iimproving energy efficiency in buildings necessitates mitigating the operation energy performance by evaluating more sustainable building components such as green infrastructures. The novelty herein is to conduct a BIM-based parametric energy analysis of green building components for the roofs and facades, taking into consideration the climate classification and orientation of the building. The proposed framework of this study uses Autodesk Revit software and Autodesk Green Building Studio as BIM tools, and Minitab software as a parametric analysis tool to estimate the energy performance of several alternative components based on Energy Use Intensity (EUI) and Annual Peak Demand (APD). A case study of a residential building is examined in four cities within different climate zones in Brazil; Rio de Janeiro (climate zone 08), Macaé (climate zone 05), Petrópolis (climate zone 03), and Nova Friburgo (climate zone 02). The base model design of components of the building includes a reinforced concrete roof and ceramic masonry façade. The utilized alternatives are roof components (i.e. green roofs and expanded clay roofs), and green façade. This work insight using green façade for all elevations and green roofs to enhance energy efficiency in terms of EUI by (10,17 %) in Rio de Janeiro, (6,67 %) in Macaé, (11,43 %) in Pertópolis, and (16,43 %) in Nova Friburgo. While the efficiency in terms of APD would be about (28,07 %) in Rio de Janeiro, (22,79 %) in Macaé, (21,67 %) in Pertópolis, and (12,58 %) in Nova Friburgo. When the construction project is designed to install a green façade to the main elevation only, this work recommends using green roofs rather than the expanded clay roof or the base model design roofs to increase energy efficiency in such types of buildings. This work contributes to integrating green building components into building designs to improve energy efficiency and empower decision-making and sustainability in buildings.

Efficient photocatalytic degradation of microplastics by constructing a novel Z-scheme Fe-doped BiO2−x/BiOI heterojunction with full-spectrum response: Mechanistic insights and theory calculations

Recently, microplastics (MPs) have garnered significant attention as a challenging emerging pollutant to address. Here, a full-spectrum light-driven Fe-doping BiO2−x/BiOI (FBI) Z-scheme heterojunction was constructed for efficiently degrading MPs in waters. Compared with BiO2−x, Fe doping BiO2−x, and BiOI, the optimal photocatalyst (40-FBI) can cause deep cracks in the polyethylene terephthalate (PET) within 10 h under the irradiation of full-spectrum light. Meanwhile, FT-IR characterization revealed that the absorption peak intensities of the C-O group, CO group, -CH stretching vibration, and -OH group on the MPs surface gradually increased with degradation time. A series of experiments and theory calculations revealed that the introduction of Fe creates impurity levels, accelerating the separation of photo-generated carriers and reducing the work function of BiO2−x, thereby enhancing the transport of photo-generated carriers between Z-scheme heterojunctions. This study offers a valuable idea for designing an efficient photocatalyst by simultaneously introducing ion doping and constructing heterojunctions for enhancing MPs degradation.

1-arcsecond imaging of the ELAIS-N1 field at 144MHz using the LoTSS survey with the international LOFAR telescope

We present the first wide area ($2.5 deg ^2$) LOFAR high band antenna image at a resolution of $1.2 with a median noise of $ Jy beam $. It was made from an 8-hour International LOFAR Telescope (ILT) observation of the ELAIS-N1 field at frequencies ranging from 120 to 168\,MHz with the most up-to-date ILT imaging methods. This intermediate resolution falls between the highest possible resolution (0.3 achievable by using all ILT baselines and the standard 6-arcsecond resolution in the LOFAR Two-meter Sky Survey (LoTSS) image products utilising the LOFAR Dutch baselines only. This is the first demonstration of the feasibility of imaging using the ILT at a resolution of sim 1 which provides unique information on source morphology at scales that fall below the surface brightness limits at higher resolutions. The total calibration and imaging computational time is approximately 52,000 core hours, which is nearly five times more than required to produce a $6 resolution image. We also present a radio source catalogue containing 2263 sources detected over the $2.5 deg ^2$ image of the ELAIS-N1 field, with a peak intensity threshold of $5.5 The catalogue has been cross-matched with the LoTSS deep ELAIS-N1 field radio catalogue, and its flux density and positional accuracy have been investigated and corrected accordingly. We find that sim 80&lt;!PCT!&gt; of sources that we expect to be detectable based on their peak brightness in the LoTSS $6 resolution image are detected in this image, which is approximately a factor of two higher than for $0.3 resolution imaging in the Lockman Hole, implying there is a wealth of information on these intermediate scales.

Evaluation of corrosion properties of TA2-Q345 explosive composite plate at different heat treatment temperatures

This study investigated the effects of post-weld heat treatment (PWHT) at 500 °C, 600 °C, 700 °C, and 800 °C on the microstructure and corrosion performance of the TA2-Q345 explosive composite plate, with TA2 as the flyer plate and Q345 as the base plate. X-ray diffraction (XRD), optical microscopy (OM), scanning electron microscopy (SEM), and energy dispersive spectroscopy (EDS) analyses were performed, alongside electrochemical experiments. The explosive welding interface of the TA2-Q345 composite plate exhibited a characteristic wavy structure, which indicated high welding quality. The XRD results indicated that the PWHT temperature significantly affects both the phase structure and the intensity of the diffraction peaks of the oxide film. Additionally, the porosity calculations demonstrated that the sample subjected to PWHT at 500 °C exhibited the lowest porosity in the surface oxide film, resulting in a denser oxide film that effectively enhanced corrosion resistance. However, as the temperature continued to rise, defects such as craters, bulges, and delamination between the oxide film and the titanium matrix were observed. The results of the electrochemical analysis indicated that, compared to untreated samples, the PWHT samples demonstrated improved corrosion resistance. Specifically, the sample with PWHT at 500 °C has the lowest corrosion current density (icorr) of 6.1892E-06 A/cm2, while the untreated sample has the highest icorr of 6.3577E-05 A/cm2, indicating that 500 °C is the optimal temperature. The corrosion process involved the hydrolysis of titanium chloride to form a TiO2 film and localized corrosion of the TiO2 protective film. The corrosion products composed of mainly C, O, and Ti were dispersed on the surface of PWHT samples.

Investigating the exciton dynamics in InGaN/GaN core-shell nanorods using time-resolved cathodoluminescence.

This study examines the exciton dynamics in InGaN/GaN core-shell nanorods using time-resolved cathodoluminescence (TRCL), which provides nanometer-scale lateral spatial and tens of picoseconds temporal resolutions. The focus is on thick (>20 nm) InGaN layers on the non-polar, semi-polar and polar InGaN facets, which are accessible for study due to the unique nanorod geometry. Spectrally integrated TRCL decay transients reveal distinct recombination behaviours across these facets, indicating varied exciton lifetimes. By extracting fast and slow lifetime components and observing their temperature trends along with those of the integrated and peak intensity, the differences in behaviour were linked to variations in point defect density and the degree and density of localisation centres in the different regions. Further analysis shows that the non-polar and polar regions demonstrate increasing lifetimes with decreasing emission energy, attributed to an increase in the depth of localisation. The semi-polar facet instead showed a spectral independence of the lifetime which could not be rationalised by an absence of exciton localisation. This investigation provides insights into the intricate exciton dynamics in InGaN/GaN nanorods, offering valuable information for the design and development of optoelectronic devices.

Participative pilot study at the vicinity of airports for the construction of a noise point counter integrating instantaneous annoyance at overflight

Current regulations on transport noise are based on energetic acoustic indicators that do not adequately reflect the intensity and repetitive nature of noise peaks, particularly for aircraft overflights or rail traffic. The public debate on these issues therefore often centres on the questioning of these indicators, which are deemed to be inadequate to reflect the annoyance caused to local populations, particularly in a context of increasing traffic. Bruitparif suggests exploring a noise events counter, the Noise Point Counter (NPC), based on existing NAX indicators but freeing itself from the threshold effect, which is a drawback to their use. The idea is to count the number of noise events, weighting each event according to the level of instantaneous annoyance it is likely to generate for local residents. To make progress on the feasibility of developing such an indicator and to confirm its relevance, Bruitparif is proposing to carry out a pilot study on three selected overflown areas in the Île-de-France region, involving around thirty local residents on each occasion. The paper will present the principle behind the creation of this new indicator as well as the pilot study protocol.

Förster Resonance Energy Transfer and Enhanced Emission in Cs4PbBr6 Nanocrystals Encapsulated in Silicon Nano-Sheets for Perovskite Light Emitting Diode Applications.

Encapsulating Cs4PbBr6 quantum dots in silicon nano-sheets not only stabilizes the halide perovskite, but also takes advantage of the nano-sheet for a compatible integration with the traditional silicon semiconductor. Here, we report the preparation of un-passivated Cs4PbBr6 ellipsoidal nanocrystals and pseudo-spherical quantum dots in silicon nano-sheets and their enhanced photoluminescence (PL). For a sample with low concentrations of quantum dots in silicon nano-sheets, the emission from Cs4PbBr6 pseudo-spherical quantum dots is quenched and is dominated with Pb2+ ion/silicene emission, which is very stable during the whole measurement period. For a high concentration of Cs4PbBr6 ellipsoidal nanocrystals in silicon nano-sheets, we have observed Förster resonance energy transfer with up to 87% efficiency through the oscillation of two PL peaks when UV excitation switches between on and off, using recorded video and PL lifetime measurements. In an area of a non-uniform sample containing both ellipsoidal nanocrystals and pseudo-spherical quantum dots, where Pb2+ ion/silicene emissions, broadband emissions from quantum dots, and bandgap edge emissions (515 nm) appear, the 515 nm peak intensity increases five times over 30 min of UV excitation, probably due to a photon recycling effect. This irradiated sample has been stable for one year of ambient storage. Cs4PbBr6 quantum dots encapsulated in silicon nano-sheets can lead to applications of halide perovskite light emitting diodes (PeLEDs) and integration with traditional semiconductor materials.

Temperature-Dependent Rotation of Protonated Methyl Groups in Otherwise Deuterated Proteins Modulates DEER Distance Distributions

AbstractTemperature-dependent DEER effects are observed as a function of methyl rotation by either leucine- or nitroxide-specific protonated methyl groups in an otherwise deuterated background. Both species induce a site-specific enhancement in the apparent Tm relaxation of the paramagnetic nitroxide label. The presence of a single protonated methyl group in close proximity (4–10 Å) to only one of the two nitroxide rotamer ensembles in AviTagged immunoglobulin-binding B domain of protein A results in a selective and substantial decrease in Tm, manifested by differential decay of the peak intensities in the bimodal P(r) distance distribution as a function of the total dipolar evolution time, temperature, or both. The temperature-dependent differential decay of the individual distance components was globally analyzed by fitting the DEER dipolar time traces to a three-site jump model that is defined by the activation energy of leucine- or nitroxide-specific methyl rotation. Temperature-assisted Tm filtering will capture the DEER structural analysis of biomolecular systems heterogenic conformations, including complexes involving multimeric proteins.