Visible Measurements Research Articles

Characterization of Graphene and Indium Tin Oxynitride Thin Films for Use as Layers in Resistive Memories

Graphene is a two‐dimensional material, comprising sp²‐hybridized carbon atoms organized in a hexagonal lattice. An application of this material lies in resistive random‐access memories (ReRAMs). In this work, resistive memory devices with three layers were manufactured. Graphene thin films were deposited by dip coating on indium tin oxynitride (ITON) electrodes. For the ITON contacts, indium tin oxide was evaporated in an oxygen atmosphere and subsequently annealed with a nitrogen flow atmosphere in a conventional furnace at different temperatures: 350, 400, 500 and 550 °C. The evaporation technique was employed to produce aluminum as top contacts. For graphene and ITON characterization, structural analysis of Raman, electrical measurements through Hall effect and optical UV – Vis measurements were performed. Resistive memories were also characterized through I × V analysis. The devices can be characterized as unipolar, with threshold switching attributed to the formation of oxygen vacancies. ITON was deposited with a substantial layer, containing oxygen, while graphene, with an average thickness of 30 nm measured by profilometer, forms a thinner layer. During the voltage increase and subsequent decrease, it is postulated that the oxygen vacancies within this material may migrate towards the intermediate layer, graphene, due to its reduced thickness and defects.

Characterization of Cs2AgInCl6: Bridging Optical and Electrical Properties for Advanced Optoelectronic Applications

ABSTRACTLead‐free double perovskites, such as Cs2AgInCl6, represent a promising class of materials for optoelectronic applications due to their favorable properties and environmental sustainability. This work focuses on the synthesis and comprehensive characterization of Cs2AgInCl6, employing a range of techniques including X‐ray diffraction (XRD) for structural verification, thermogravimetric analysis (TGA) to assess thermal stability, and UV–visible absorption measurements to determine the optical bandgap energy of 3.32 eV. Additionally, we explore photoluminescence (PL) and decay measurements to elucidate the luminescent properties of the compound. Complex impedance measurements are performed under both blue and red light to investigate the electrical behavior, revealing two distinct conduction mechanisms: the overlapping large–polaron tunneling (OLPT) and nonoverlapping small–polaron tunneling (NSPT). We analyze the implications of our findings on the current–voltage (I–V) behavior and trap density, further supported by Raman spectroscopy under both illumination conditions. The combined insights from optical and electrical characterizations highlight the potential of Cs2AgInCl6 in optical applications, paving the way for its use in advanced optoelectronic devices.

The Conscious Side of 'Subliminal' Linguistic Priming: A Systematic Review With Meta-Analysis and Reliability Analysis of Visibility Measures.

Research on unconscious processing has been a valuable source of evidence in psycholinguistics for shedding light on the cognitive architecture of language. The automaticity of syntactic processing, in particular, has long been debated. One strategy to establish this automaticity involves detecting significant syntactic priming effects in tasks that limit conscious awareness of the stimuli. Criteria for assessing unconscious priming include the visibility (d') of masked words not differing significantly from zero and no positive correlation between visibility and priming. However, such outcomes could also arise for strictly methodological reasons, such as low statistical power in visibility tests or low reliability of dependent measures. In this study, we aimed to address these potential limitations. Through meta-analysis and Bayesian re-analysis, we find evidence of low statistical power and of participants having above-chance awareness of 'subliminal' words. Moreover, we conducted reliability analyses on a dataset from Berkovitch and Dehaene (2019), finding that low reliability in both syntactic priming and visibility tasks may better explain the absence of a significant correlation. Overall, these findings cast doubt on the validity of previous conclusions regarding the automaticity of syntactic processing based on masked priming effects. The results underscore the importance of revisiting the methods employed when exploring unconscious processing in future psycholinguistic research.

Synthesis of ABCBA‐Type Pentablock Copolymers via Sequential Ring‐Opening, Free Radical, and Photoinduced Free‐Radical‐Promoted Cationic Polymerization Methods

ABSTRACTThis study reports the synthesis and characterization of ABCBA‐type pentablock copolymers comprising poly(cyclohexene oxide) (PCHO) as the A block, poly(ε‐caprolactone) (PCL) or poly(L‐lactide) (PLLA) as the B block, and polystyrene (PSt) as the C block. The target pentablock copolymers, PCHO‐PCL‐PSt‐PCL‐PCHO and PCHO‐PLLA‐PSt‐PLLA‐PCHO, were synthesized through a sequential combination of ring‐opening polymerization (ROP), free radical polymerization (FRP), and, for the first time to the best of our knowledge, photoinduced free‐radical‐promoted cationic polymerization (FRPCP) in pentablock copolymer synthesis. In the initial ROP step, well‐defined Bz‐PCL and Bz‐PLLA macrophotoinitiators were synthesized with photoactive benzoin (Bz) end groups. Next, Bz‐PCL and Bz‐PLLA were converted to the macro‐azo initiators, Bz‐PCL‐NN‐PCL‐Bz and Bz‐PLLA‐NN‐PLLA‐Bz, by esterification with 4,4′‐azobis(4‐cyanovaleric acid) (ACVA). These macro‐azo initiators were employed as initiators in the FRP of styrene to form triblock copolymers, which were then used as prepolymers in the photoinduced FRPCP of cyclohexene oxide (CHO) to produce the pentablock structures. Structural characterization conducted via FT‐IR and 1H NMR spectroscopy confirmed the presence of each polymer segment within the pentablock architecture, and gel permeation chromatography (GPC) analysis further validated pentablock formation, showing unimodal distributions. UV–Vis and fluorescence measurements also verified the successful incorporation of the benzoin groups. This multistep synthetic strategy introduces an effective approach for constructing ABCBA‐type pentablock copolymers, which might find the potential uses in advanced material design.

Water and Oil Volume Measurement Using UV–Visible Spectroscopy

Fluid saturation in relative permeability experiments is typically determined by volumetric or gravimetric measurements, as well as in-situ saturation monitoring (ISSM). Gravimetric measurements tend to have larger error due to grain loss. The conventional volumetric method used can be a challenge because produced volumes for oil and water must be separated and measured manually. ISSM method is also a costly technique. In this study, an UV–visible spectroscopy was used to continuously and cost effectively measure oil and water volumes. A water-oil unsteady state relative permeability was performed to investigate the feasibility of calculating oil and water volumes using UV–visible spectroscopy. UV–visible spectroscopy is a quantitative technique in analytical chemistry to determine concentrations of known solutes. A UV–visible spectroscope was located in the flow line immediately after the core holder and used to quantify fluid volumes (oil and water) produced from a core sample during unsteady state relative permeability study. A volumetric separator was also used to compare production volumes obtained from UV–visible spectroscope. The relative permeabilities were calculated using JBN method from both volumetric and UV-visible spectroscope measurements and then history matched with Sendra (PRORES AS). The final oil volume produced, oil and water relative permeability curves obtained from UV–visible spectroscope measurements were in good agreement with volumetric measurements. The Corey relative permeability curves simulated from Sendra also were closely matched with analytical relative permeability curves obtained using volume measurements from volumetric and UV–visible spectroscope data. Nuclear Magnetic Resonance (NMR) on post relative permeability experiment was also in good agreement with UV–visible spectroscope measurement. UV–visible spectroscopy was also used to measure the breakthrough time of the injected fluid. Breakthrough time estimated using in-line UV–visible spectrophotometer was 0.634 PVI compared to 0.617 and 0.673 PVI from pressure data and volumetric observations.Graphic

Study on Adsorption and Desorption Mechanism of CuO Particles on the Post-CMP Wafer Surface of Multi-Layered Copper

In the process of chemical mechanical polishing (CMP), the removal of surface pollution contamination on the wafer surface is an urgent problem to be solved, and the CuO removal is important for the cleaning after CMP. In this paper, a new type of alkaline cleaning solution based on composite complexing agent was proposed for CuO particles removal. The optimal concentration of the cleaning solution was explored using static corrosion rate and electrochemical quartz crystal microbalance measurements. When the components were 200 ppm FA/OII chelating agent and 0.1 vol% ammonium citrate, CuO residue on copper surface can be effectively removed. It can be confirmed that CuO cleaning depends mainly on the complexation of composite complexing agent. Scanning electron microscopy showed that a lower surface roughness was obtained after cleaning. X-ray photoelectron spectroscopy and UV–vis measurements confirmed that the synergistic effect of FA/OII chelating agent and ammonium citrate could effectively remove copper oxide contamination on the surface. The ratio of copper oxide on copper surface after CMP decreased significantly to 8.86%.

The pathways linking green spaces to reduced climate change anxiety

Exposure to green space could by hypothesized as having the potential to alleviate climate change anxiety. However, empirical evidence is lacking. This study aimed to explore the relationship between green space exposure and climate change anxiety, and to determine whether this association was mediated by green physical activity, extreme weather, and environmental comfort. Through an online survey with geographic location tracking capabilities, we calculated greenness values using the Normalized Difference Vegetation Index (NDVI) and forest cover around the homes of 653 participants, as well as self-reported measures of green space and visibility of trees from their windows. Two domains of climate change anxiety (emotional and cognitive impairment and functional impairment), generalized anxiety disorder, green physical activity (frequency of green walking and green leisure physical activity), extreme weather, and environmental comfort were also measured by questionnaire. A generalized additive model was used to test for nonlinear trends. Subsequently, structural equation modeling was employed to assess the mediating effects. Our results showed a weak linear relationship (p < 0.10) between perceived green space and functional impairment related to climate change anxiety, with environmental comfort playing a mediating role in this relationship. In sensitivity analyses where the outcome variables were binary coded (low and high levels of climate change anxiety), perceived green space was associated with a reduced risk of climate change anxiety (p < 0.05). Overall, we found limited evidence for green space exposure being associated with less climate change anxiety. Given the preliminary nature and limitations of this research, we call for future studies to examine these findings using better measurements, larger and more diverse populations, and more rigorous methods conducive to causal inference.

A new luminescent material based on bismuth(III): Synthesis, structural characterization, DFT calculations, Hirshfeld surface, thermal behavior, vibrational and optical properties

Bismuth-halide-based hybrid materials are desirable in luminescent applications due to low toxicity and chemical stability. (C8H12N)4Bi2Cl10, was elaborated by the slow evaporation technique at room temperature. Single-crystal X-ray diffraction analysis indicates that the compound belongs to the monoclinic crystal system with the centrosymmetric space group P21/c. The formula unit comprises four protonated organic cations (C8H12N)4+, one [Bi2Cl10]4− dimer. The organic layers are inserted between the inorganic ones and connected with N-H…Cl and C-H…Cl hydrogen bonds to build a three dimensional network. The infrared IR and Raman studies which were recorded at room temperature in the 500–4000 cm−1 and 50–4000 cm−1 frequency regions, respectively, confirmed the existence of vibrational modes that correspond to the organic and inorganic groups. The optimized molecular structure and vibrational frequencies were calculated by the Density Functional Theory (DFT) method using the B3LYP level employing level employing a LANL2DZbasis set. It shows a good agreement between the calculated and the experimental vibrational frequencies. Hirshfeld surface analysis of close intermolecular interactions in this compound enables the identification and examination of molecular shapes. The crystal exhibits thermal stability up to 160 °C using the Thermogravimetric analysis TGA. The optical properties were characterized experimentally by UV–visible absorption studies and photoluminescence measurements. The Photoluminescence spectrum shows a green luminescence peak which is attributed to excitonic emissions within the chlorobismuthate octahedron. HOMO-LUMO orbital energies were studied by using DFT calculations.

Excited State Dynamics of Geometrical Evolution of α-Substituted Dibenzoylmethanatoboron Difluoride Complex with Aggregation-Induced Emission Property.

Organic molecules with an aggregation-induced emission (AIE) property have been attracting much attention from the viewpoint of application to solid state emissive materials. For the AIE mechanism, quantum mechanical studies proposed the restriction of the intramolecular motion (RIM) model with the contribution of the conical intersection (CI) and deduced the importance of the restricted access to a conical intersection (RACI) in the potential energy surface (PES). Although these theoretical studies have contributed to the elucidation of AIE phenomena, direct detection of the reaction dynamics is indispensable to clarify the actual PES and the deactivation mechanism. Along this line, we investigated excited state dynamics of the AIE molecule with dibenzoylmethanatoboron difluoride complexes using time-resolved absorption spectroscopies in both visible and infrared (IR) regions. While the reference system of 1,3-bis(4-methoxyphenyl)methanatoboron difluoride (2aBF2) showed strong emission in solution, the methyl-substituted derivative at the α-position of the dioxaborine ring (2amBF2) led to the very weak fluorescence in solution but strong emission in the solid state. Time-resolved visible absorption measurements revealed a peak shift and broadening of the stimulated emission in the solution of 2amBF2, owing to the rapid change of the molecular geometry. With the temporal evolution of time-resolved IR absorption signals and density functional theory (DFT) calculation of these systems, it was deduced that 2amBF2 has two stable geometries, namely, planar and bending, in the S1 state and the bending geometry in the S1 state led to rapid conversion to the S0 state. These results support the RACI model in the aggregated states, leading to the AIE properties.

The Influence of Relative Humidity and Pollution on the Meteorological Optical Range During Rainy and Dry Months in Mexico City

The Meteorological Optical Range (MOR) is a measurement of atmospheric visibility. Visibility impairment has been linked to increased aerosol levels in the air. This study conducted statistical analyses using meteorological, air pollutant concentration, and MOR data collected in Mexico City from August 2014 to December 2015 to determine the factors contributing to haze occurrence (periods when MOR &lt; 10,000 m), defined using a light scatter sensor (PWS100). The outcomes revealed seasonal patterns in PM2.5 and relative humidity (RH) for haze occurrence along the year. PM2.5 levels during hazy periods in the dry season were higher compared to the wet season, aligning with periods of poor air quality (PM2.5 &gt; 45 μg/m3). Pollutant-to-CO ratios suggested that secondary aerosols’ production, led by SO2 conversion to sulfate particles, mainly impacts haze occurrence during the dry season. Meanwhile, during the rainy season, the PWS100 registered haze events even with PM2.5 values close to 15 μg/m3 (considered good air quality). The broadened distribution of extinction efficiency during the wet period and its correlation with RH suggest that aerosol water vapor uptake significantly impacts visibility during this season. Therefore, attributing poor visibility strictly to poor air quality may not be appropriate for all times and locations.

Comparative study of zirconium-zinc oxide thin films on ceramic and glass substrates: Structural, optical, and photocatalytic properties

This study investigates the structural, optical, and photocatalytic properties of zirconium-doped zinc oxide (Zr) thin films deposited on ceramic and glass substrates. X-ray diffraction (XRD) analysis revealed that all samples exhibited a polycrystalline wurtzite structure, with grain sizes ranging from 25 to 43 nm for ceramic substrates and 19 to 32 nm for glass substrates. UV–visible absorbance measurements indicated that Zr films absorbed visible light around 410 nm, with the band gap widening to 2.93 eV on ceramic substrates. Scanning electron microscopy (SEM) showed that Zr doping significantly affected the morphology of thin films, resulting in rougher surfaces and larger grains on ceramic substrates. Photocatalytic tests demonstrated that the 5 wt% Zr on DD1Z ceramic achieved a degradation efficiency of 61.44 % for orange II dye after 5 h of UV irradiation. In contrast, Zr on ceramic substrates achieved only 18.56 %, and the bare DD1Z substrate reached just 4.02 %. These findings highlight the superior photocatalytic performance of Zr on ceramic substrates, indicating their potential for advanced water purification technologies. The mechanism of photolysis was investigated using hole/radical scavengers, revealing that Zr-ZnO networks enhance the adsorption of hydroxyl ions on the surface. This acts as a trap site, reducing hole/electron pair recombination and thus increasing activity and photodegradation efficiency.

One-pot synthesis of copper phthalocyanine polymer: An efficient CO2 fixation catalyst

The chemical transformation of CO2 into high-value-added products is not only favourable to environmental preservation, but also promising for economy. Developing novel and practical catalysts play a critical role in facilitating conversion of CO2 and the synthesis of high value-added chemicals. Herein, we present the fabrication of biphenyl-typed copper phthalocyanine polymer (BPh-CuPc) from 4,4’-bis(3,4-dicyanophenoxy)biphenyl via a one-pot synthesis procedure, and application of it as a promising catalyst for CO2 conversion into cyclocarbonate. FTIR, XPS, UV–vis, TGA and SEM measurements confirm the successful fabrication of BPh-CuPc. Attributing to the existence of copper ions which can act as a Lewis acid to activate epoxide, and phthalocyanine rings that is positive for CO2 absorption, within the chemical framework of BPh-CuPc, it exhibits excellent catalytic activity for CO2 conversion into cyclic carbonates under mild conditions when combined with tetrabutylammonium iodide (TBAI). As a result, a 98 % yield and 99 % selectivity are obtained for the BPh-CuPc/TBAI system in CO2/propylene oxide conversion under condition of 90 °C, 8 h and 2.0 MPa. The obtained high yield and selectivity, as well as remarkable stability and versatility, validate the promising application of BPh-CuPc as a CO2 conversion catalyst. SynopsisAttributing to the existence of copper ions and phthalocyanine rings within the chemical framework, BPh-CuPc exhibits excellent catalytic activity for CO2 conversion into cyclic carbonates under mild conditions.

Application and electrochemical depression mechanism of sodium sulfite on the flotation separation of galena–pyrite mixed concentrate in Yiliang typical high‑sulfur lead–zinc deposit

The high content of pyrite in high‑sulfur lead–zinc sulfide resources affects the electrochemical properties and floatability of galena and sphalerite, which results in difficult flotation separation. In this study, the negative effects of a high-alkaline process were weakened by introducing an efficient mixed depressant CaO + Na2SO3 in selective flotation separation of galena from pyrite. Flotation separation tests of real ore samples showed that the mixed depressant was more efficient than single CaO (5000 g/t), and the best process conditions of Pb grade 64.01 % and Pb recovery 88.45 % were obtained. The effects of Na2SO3 on the electrochemical interaction between the two minerals were studied by micro-flotation tests, electrochemical, ion dissolution, UV–Vis measurements, zeta potential measurements, and X-ray photoelectron spectroscopy (XPS) detections. Results indicated that Na2SO3 could weaken the galvanic interaction between galena–pyrite and reduce the Pb2+ dissolution from the galena surface. Na2SO3 could desorb the collector ethyl xanthate pre-adsorbed on the pyrite surface.

Achieving high electrothermal and mechanical performance for Graphene/Poly(hexamethylene terephthalamide) composite films via interfacial engineering with two-dimensional polyarylamide nanosheets

Although graphene-based polymer electrothermal films have received great attention, the graphene aggregation restricts the improvement in electrothermal performance. This study reports graphene (GN)/two-dimensional polyarylamide nanosheets (2DPA) filled poly (hexamethylene terephthalamide) (PA6T) composite film with outstanding electrothermal and mechanical performance. Owing to the addition of 2DPA, the as-prepared 2DPA-GN/PA6T composite film can attain a high heating-up rate of 25.5 °C/s, 1.8 times higher than that of GN/PA6T composite film (14.1 °C/s). Furthermore, the 2DPA-modified composite film showed a remarkable heating temperature rise to ∼230 °C, 80 °C higher than that of GN/PA6T composite film (∼150 °C). Additionally, the film had excellent mechanical performance with tensile strength and modulus of elasticity of 32.5 MPa and 4.6 GPa, which were 24.2 % and 52.3 % higher than that of GN/PA6T composite film, respectively. Such outstanding performance came from strong interfacial adhesion between GN and PA6T, induced by 2DPA nanosheets through hydrogen bonding and π-π interactions, which were confirmed by FTIR and UV–Vis measurements. Besides improving interfacial adhesion, 2DPA can also reduce the surface defect density of the GN through π-π conjugation. Both improved interfacial adhesion and reduced defects of GN contributed to the formation of electrically conductive and stress transfer pathways, which supported the excellent electrothermal and mechanical properties of 2DPA-GN/PA6T composite films. This study demonstrates an effective way to prepare high-performance graphene composites for electrothermal applications, with expected uses in aerospace, industry, and other technological fields.

Characteristic of temporal light modulation reference meter and standard light source for calibration and verification

Abstract The measurement of the temporal light modulation (TLM) of a light source is gaining increasing importance owing to its detrimental effects on human vision and health. To establish traceability in TLM measurements, the National Institute of Metrology, China (NIM), established a TLM reference meter (TLMM) and standard TLM light source (STLS) for calibration and verification services. The TLMM and STLS employ detector- and source-based approaches, respectively, to define the standards for TLM quantities. The TLMM rapidly acquires light waveform data from the TLM light sources and calculates corresponding TLM quantities. Frequency calibration result is with an expanded uncertainty of 1 × 10−5, frequency response function is almost flat in range of 1 kHz–25 kHz, and response time is less than 8 × 10−6 s. The electrical noise was evaluated at approximately 1000:1–5000:1. The STLS generates an arbitrary TLM waveform by converting the virtual waveform into an actual LED output light waveform. For the frequency response function, the relative amplitude decreased by 1% with a frequency of 15 kHz, and response time was less than 5 × 10−6 s. The linearity of the frequency dependency was studied with ratio varied by approximately 0.19% when the periodic triangle excitation in frequency band from 1 Hz to 1 kHz. Experimental comparisons demonstrated that TLM quantities (frequency, percentage flicker, flicker index, short-term flicker severity P st LM , and stroboscopic effect visibility measure ( SVM )) are consistent between the TLMM and STLS devices on 14 typical TLM waveforms. For P st LM , most of the deviations were in the range of −0.019–0.079 (except for one with 0.182). For SVM , most of the deviations were in the range of −0.001–0.003 (except for one with 0.014).

Eco-friendly Chlorella vulgaris extracts for corrosion protection of steel in acidic environments

This study evaluates the potential of Chlorella vulgaris sp. extracts as eco-friendly corrosion inhibitors for API 5L 42 Steel in a 1M HCl acidic environment, offering sustainable alternatives for industrial applications. Two corrosion inhibitors were obtained through solvent extraction methods: M1 (methanol) and M2 (methanol/chloroform). The extracts were characterized using infrared spectroscopy, the analysis revealed hydroxyl, methyl and vinyl groups as the most representative. The effect of corrosion inhibition was study by electrochemical impedance spectroscopy (EIS) and potentiodynamic polarization. The results show significant reductions in corrosion current density and increases in charge transfer resistance, with M2 achieving the highest protection efficiency of 91.20 % and a charge transfer resistance of 501.80 Ω at a 120 ppm concentration, while M1 reached 88.22 % efficiency with a charge transfer resistance of 102.30 Ω. Uv–Vis measurements were performed to determine the electronic transitions of the metal-inhibitor system for each of the extracts. ANOVA highlighted the significant influence of biomass concentration on corrosion resistance. The adsorption of M1 and M2 extracts on the carbon steel surface obeyed the Langmuir isotherm and Gibbs free energy calculations indicated a physisorption mechanism for both extracts. Surface morphology analysis by Scanning electron microscope (SEM) revealed less pitting and reduced surface roughness as inhibitor concentration increased. These findings underscore the potential of Chlorella vulgaris extracts, particularly M2 at 120 ppm, as effective and sustainable corrosion inhibitors for steel in acidic environments.

Enriched photocatalytic degradation of methylene orange dye using carbon quantum dots surface-decorated TiO2 nanocomposites

Complex molecules in methylene orange (MO) dye-contaminated water are carcinogenic and mutagenic risks to human health. Carbon quantum dot surface-decorated titanium dioxide nanocomposites (CQD-TiO2 NCs) were synthesized via a sustainable hydrothermal method at concentrations of 1.5–3 mL. These NCs exhibits superior electron transfer, light harvesting capabilities, high stability, easy modification, optical characteristics, and photocatalytic properties. The surface morphology, porosity, physiochemical, and optical features of these CQD-TiO2 NCs were characterized using TEM, UV–Vis, PL, BET, BJH micromeritics, pHzpc, and photoelectrochemical measurements. The prepared NCs were evaluated against the photocatalytic degradation of MO dye molecules using a solar simulator system. The TEM revealed ultra-sensitive and tiny CQD materials with graphite phases ranging from 5 to 10 nm and attached to the octahedron surface of TiO2 NCs. The PL analysis observed three distinct emission peaks in the visible region, attributed to the near band edge, interstitial (Tii), and oxygen vacancy (V0). The BET and BJH analyses were conducted to determine the N2 adsorption-desorption surface area and mesoporous structure with pore sizes ranging from 2 to 50 nm. These NCs showed excellent photocatalytic performance, effectively degrading MO up to 99.00 % in a 3 mL variation, indicating that they could be a great candidate for photocatalytic purification of wastewater containing MO dyes.

Investigation on electronic and magnetic properties of Cr doped V2O5 thin films prepared by chemical solution deposition method

The present study examines the role of Cr doping on the electronic and magnetic behaviour of V2O5i.e. V2-xCrxO5 (x = 0, 0.05, and 0.10) thin films, prepared by chemical-solution deposition technique on Si (111) substrate. X-Ray diffraction technique shows the purity of the films and confirms no secondary phase formation. The atomic force microscopy was used to confirm the roughness of the films. A morphological investigation is done using High-resolution scanning electron microscopy associated with Energy dispersive X-Ray mapping of each element of the film. Fourier transform Infrared spectroscopy is utilised to identify functional groups that are present in obtained samples. The band-gap of these obtained samples is in the range of 0.8–0.6 eV, as examined by UV–Vis i.e., its value is decreasing with Cr doping. Using vibrating sample magnetometer, it is clear that samples shows ferromagnetic (FM) behaviour with saturation magnetization 0.3–0.6 μB/cc consistent with Langevin function fitting. It concludes the presence of FM behaviour of films and magnetization increases with carrier density, consistent with the carrier-induced origin of the ferromagnetism. X-ray photoemission spectroscopy (XPS) is utilised to understand its electronic properties. Core level spectra measurements suggest that V is in mixed state of 5+ and 4+. However Cr is in 3+ states. XPS and UV–Vis measurements imply that oxygen vacancies significantly contribute to the declination of the band gap and the promotion of FM-like behaviour. This discovery offers a promising pathway for engineering novel devices.

Visibility and annoyance of the phantom array effect varies with age and history of migraine

The phantom array effect (PAE) is a series of repeated images that may be perceived when a person moves their eyes in large saccades across a light source (or a specular reflection of that light source) that is modulating in output over time. Fifty-five people, including a group of 25 who experience migraine, evaluated the visibility and annoyingness of phantom arrays produced by 85 unique temporal light modulation waveforms (including sine, rectangular, complex and DC waveforms) generated using an LED placed against a black background. Those with migraine exhibited higher average visibility compared to those without migraine ( p = 0.019) and were relatively more sensitive at higher frequencies ( p &lt; 0.001). Younger participants also found more stimuli to be visible ( p &lt; 0.001). The threshold sensitivity function was similar to that developed for the phantom array visibility measure (PAVM), and PAVM was effective in predicting visibility ( R2 = 0.87 for the relevant region of PAVM &lt; 3). While those in the migraine group did not report seeing the PAE more often in everyday life at a statistically significant level, they reported being more annoyed by it and having more unwanted physiological responses (headaches, eye fatigue and distraction/disorientation). Members of the migraine group were also more likely to have changed their behaviour in architectural spaces (such as leaving a restaurant with ‘flickering’ lights). In the four hours after completing the experiment, 64% of the migraine group (vs. 19% of the non-migraine group) reported experiencing discomfort or an adverse reaction. In particular, 41% reported experiencing a headache (vs. 8% for those in the non-migraine group).

Using space lidar to infer bubble cloud depth on a global scale

Visible and microwave satellite measurements can provide the global whitecap fraction. The bubble clouds are three-dimensional structures, and a space-based lidar can provide complementary observations of the bubble depth. Here, we use lidar measurements of the Cloud-Aerosol Lidar and Infrared Pathfinder Satellite Observation (CALIPSO) satellite to quantify global bubble depth from the depolarization. The relationship between CALIPSO bubble depth and wind speed from the Advanced Microwave Scanning Radiometer for EOS (AMSR-E) and AMSR2 is similar to a recently derived relationship based on buoy measurements. The CALIPSO-based bubble depth data show global distributions and seasonal variations consistent with the high wind speed (> 7 m/s) but with some variance. We also found similarities between the CALIPSO bubble depth and the whitecap fraction from AMSR2 and WindSat. Our findings support the use of spaceborne lidar measurements for advancing the understanding of the 3D bubble properties, and the ocean physics at high wind speeds.