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Thermally activated delayed fluorescent (TADF) and phosphorescent blue organic light‐emitting diodes (OLEDs) have been developed to overcome the relatively low triplet exciton utilization of traditional fluorescent OLEDs. However, broad emission spectra originating from charge transfer process limits the commercial application of such blue OLEDs. Herein, an effective phosphor‐sensitized fluorescent (PSF) OLED device structure was designed. PSF OLED exhibited a maximum blue index (BI) of 508 cd/A/CIEy with CIEy of 0.060, which has been the highest efficiency result reported for PSF deep‐blue OLEDs. Impressively, the sensitized OLEDs maintained blue index of 407 cd/A/CIEy, narrow emission spectra (FWHM = 17 nm) and high color purity (CIEy = 0.046), revealing the attractive technical advantages and commercial application potential. [ABSTRACT FROM AUTHOR]

Efficient and stable blue is the holy grail of OLED. beeOLED pioneers intra‐metallic Europium emitter that offer a unique combination of deep blue single peak emission spectrum, open shell electronic configuration for 100% efficiency, and potential of high operational stability as no organic bonds are weakened during light generation. [ABSTRACT FROM AUTHOR]

The development of the ultrapure and highly efficient blue organic light‐emitting diodes is a very critical issue in the organic light‐emitting diodes. As an approach, boron‐nitrogen based multi‐resonance compounds have been developed. In this work, a new class of materials were designed and synthesized as the deep blue organic emitters for high efficiency organic light‐emitting diodes. Only carbon and nitrogen were used to design the materials to induce the multi‐resonance effect in the emitters. A deep blue color, a narrow emission spectrum and high efficiency by thermally activated delayed fluorescence were achieved using the new emitting materials. [ABSTRACT FROM AUTHOR]

The myofibrillar protein (MP) of duck meat is prone to excessive oxidation during thermal processing, resulting in a decline in its overall quality. In this paper, the effect of shikimic acid on the oxidative structure of duck muscle fibrin was studied. The findings showed that, at a mass ratio of 1:50,000 (g/g) between shikimic acid and MP, the carbonyl content of MP was reduced by 74.20%, while the sulfhydryl content was increased by 73.56%. MP demonstrated the highest denaturation temperature, whereas its thermal absorption was the lowest. The percentage of α-helixes and β-sheets increased by 16.72% and 24.74%, respectively, while the percentage of irregular structures decreased by 56.23%. In addition, the surface hydrophobicity index of MP exhibited a significant decrease (p < 0.05), while there was a significant increase in its free radical-scavenging ability (p < 0.05). Molecular fluorescence spectrum analysis showed that shikimic acid could bind to MP, altering the internal environment of MP and enhancing its thermal stability. FTIR analysis showed that shikimic acid could enhance the distribution of protein particle sizes by reducing irregular structures, the proportion of β-rotation, and the degree of protein aggregation. It is hoped that this research can offer scientific support for improving meat processing technology. [ABSTRACT FROM AUTHOR]

At a time when the botanical origin of honey is being increasingly falsified, there is a need to find a quick, cheap and simple method of identifying its origin. Therefore, the aim of our work was to show that fluorescence spectrometry, together with statistical analysis, can be such a method. In total, 108 representative samples with 10 different botanic origins (9 unifloral and 1 multifloral), obtained in 2020–2022 from local apiaries, were analyzed. The fluorescence spectra of those samples were determined using a F-7000 Hitachi fluorescence spectrophotometer, Tokyo, Japan. It is shown that each honey variety produces a unique emission spectrum, which allows for the determination of its botanical origin. Taking into account the difficulties in analyzing these spectra, it was found that the most information regarding botanical differences and their identification is provided by synchronous cross-sections of these spectra obtained at Δλ = 100 nm. In addition, this analysis was supported by discriminant and canonical analysis, which allowed for the creation of mathematical models, allowing for the correct classification of each type of honey (except dandelion) with an accuracy of over 80%. The application of the method is universal (in accordance with the methodology described in this paper), but its use requires the creation of fluorescence spectral matrices (EEG) characteristic of a given geographical and botanical origin. [ABSTRACT FROM AUTHOR]

The autofluorescence of erythrocyte porphyrins has emerged as a potential method for multi-cancer early detection (MCED). With this method's dependence on research-grade spectrofluorometers, significant improvements in instrumentation are necessary to translate its potential into clinical practice, as with any promising medical technology. To fill this gap, in this paper, we present an automated ratio porphyrin analyzer for cancer screening (ARPA-CS), a low-cost, portable, and automated instrument for MCED via the ratio fluorometry of porphyrins. The ARPA-CS aims to facilitate cancer screening in an inexpensive, rapid, non-invasive, and reasonably accurate manner for use in primary clinics or at point of care. To accomplish this, the ARPA-CS uses an ultraviolet-excited optical apparatus for ratio fluorometry that features two photodetectors for detection at 590 and 630 nm. Additionally, it incorporates a synchronous detector for the precision measurement of signals based on the Walsh-ordered Walsh–Hadamard transform (WHT)w and circular shift. To estimate its single-photodetector capability, we established a linear calibration curve for the ARBA-CS exceeding four orders of magnitude with a linearity of up to 0.992 and a low detection limit of 0.296 µg/mL for riboflavin. The ARPA-CS also exhibited excellent repeatability (0.21%) and stability (0.60%). Moreover, the ratio fluorometry of three serially diluted standard solutions of riboflavin yielded a ratio of 0.4, which agrees with that expected based on the known emission spectra of riboflavin. Additionally, the ratio fluorometry of the porphyrin solution yielded a ratio of 49.82, which was ascribed to the predominant concentration of protoporphyrin IX in the brown eggshells, as confirmed in several studies. This study validates this instrument for the ratio fluorometry of porphyrins as a biomarker for MCED. Nevertheless, large and well-designed clinical trials are necessary to further elaborate more on this matter. [ABSTRACT FROM AUTHOR]

This paper reports a pioneering attempt at simultaneously analyzing gadolinium (Gd) distribution and surface imaging of surrogate debris samples with homogeneous and heterogeneous composition using a fiber-coupled acoustic wave-assisted microchip laser-induced breakdown spectroscopy (AW-mLIBS) system. This system must be applied to the remote analysis of fuel debris at the Fukushima Daiichi Nuclear Power Station (FDNPS). In the AW-mLIBS system, a microchip LIBS was used to measure the Gd distribution maps in the mixed oxide samples. Whereas, during elemental mapping by microchip LIBS, the laser-plasma acoustic waves were simultaneously recorded by microphone and applied for surface imaging of the samples. Additionally, the laser-plasma acoustic waves can be used to adjust the best-focusing position of the microchip LIBS because the acoustic wave amplitude is the strongest at the near best-focusing position. According to the measurement results, the emission spectra of the surrogate debris showed that the optical emission lines at 501.5 nm and 510.3 nm were suitable for Gd detection in the fuel debris sample. For Gd quantification, calibration curves were established from the intensity ratio of Gd/Ce emission lines, yielding the detection limits for Gd in the range of 0.04–0.09 wt% with a relative standard deviation of 3.9%. The surface imaging for the surrogate debris samples was successfully performed by collecting the laser-plasma acoustic waveforms during LIBS elemental mapping. [ABSTRACT FROM AUTHOR]

Multiple monochromatic x-ray imaging (MMI) is a technique for diagnosing the emission spectra of tracer elements in laser-driven inertial confinement fusion experiments. This study proposes an MMI method that combines a simple pinhole array with a laterally graded multilayer mirror. The method directly obtains multiple monochromatic x-ray images by regulating the multilayer thickness in different mirror positions to compensate for the energy-broadening effect. This paper presents a comprehensive design scheme, the multilayer fabrication and experimental verification of the gradient MMI imaging performance. The experimental results show that the method achieves monochromatic imaging with a spectral resolution of ∼70–90 eV in several keV energy regions. This paper presents a practical diagnostic approach for directly and synchronously capturing the spatial, temporal, and spectral information of laser plasma x rays. [ABSTRACT FROM AUTHOR]

This paper proposes a deep learning method to predict the electromagnetic emission spectrum in the electromagnetic compatibility (EMC) test of aerospace products. A threshold‐based data decomposition method is used to propose the spike signal, reconstruct the original test data, and solve the contradiction between the overfitting and prediction accuracy of the deep learning method to deal with the EMC test spectrum. Using a long short‐term memory neural network architecture for predicting electromagnetic emission spectrum, the Bayesian optimization method is used to optimize the network hyperparameter, and the acquisition function is introduced into the loss function to improve the comprehensive training optimization of deep learning network. Apply the method to three numerical examples: signal line current conduction emission, power line voltage conduction emission, and electric field radiation emission. The analysis results indicate that at a 95% confidence level, the predicted electromagnetic emission spectrum is basically consistent with the test results. The prediction results can be used as the basis for EMC evaluation of aerospace electronic equipment. [ABSTRACT FROM AUTHOR]

Southern leaf blight (SLB) is a foliar disease caused by the fungus Cochliobolus heterostrophus infecting maize plants in humid, warm weather conditions. SLB causes production losses to corn producers in different regions of the world such as Latin America, Europe, India, and Africa. In this paper, we demonstrate a non-destructive method to quantify the signs of fungal infection in SLB-infected corn plants using a deep UV (DUV) fluorescence spectrometer, with a 248.6 nm excitation wavelength, to acquire the emission spectra of healthy and SLB-infected corn leaves. Fluorescence emission spectra of healthy and diseased leaves were used to train an Autoencoder (AE) anomaly detection algorithm—an unsupervised machine learning model—to quantify the phenotype associated with SLB-infected leaves. For all samples, the signature of corn leaves consisted of two prominent peaks around 450 nm and 325 nm. However, SLB-infected leaves showed a higher response at 325 nm compared to healthy leaves, which was correlated to the presence of C. heterostrophus based on disease severity ratings from Visual Scores (VS). Specifically, we observed a linear inverse relationship between the AE error and the VS (R2 = 0.94 and RMSE = 0.935). With improved hardware, this method may enable improved quantification of SLB infection versus visual scoring based on e.g., fungal spore concentration per unit area and spatial localization. [ABSTRACT FROM AUTHOR]

Fluorescence pH sensing has proven to be efficient but with the drawback that molecules photobleach, requiring frequent calibrations. Double-emission peak molecules allow ratiometric measurements and theoretically avoid calibration. However, they are often expensive and fragile and usually have very low quantum yields. Single emission peaks such as fluorescein and derivatives are inexpensive and have very high quantum yields. Because they are single emission peaks, the pH is assumed to be derived from the ratio of emitted intensities at measured pH and at high pH values, i.e., they require frequent calibration. However, the shape of their single emitted peak evolves slightly with pH. In this paper, we first demonstrate a simple method to calculate the emission spectrum shape of each prototropic form of fluorescein (and derivatives) as well as the values of the pKas. A complete model of the evolution of the emission spectrum shape with pH is then constructed. Second, we evaluate the potential of these molecules for pH sensing by fitting the experimental spectra with the complete emission model. The method is applied to fluorescein, FITC and FAM. Depending on the molecule, pH can be measured from pH 1.9 to pH 7.3 with standard deviations between 0.06 and 0.08 pH units. Estimating pH and pKas from shape instead of intensity allows calibration-free measurements even with single-emission peak molecules. [ABSTRACT FROM AUTHOR]

The shot-to-shot measurement uncertainty restricts the application of laser-induced breakdown spectroscopy (LIBS) technically, to a certain extent. In order to further deepen the understanding of spectral stability, in this paper, the effects of the laser's focus depth, the delay of the spectrometer, and the position of the spectrum collection on the spectral stability were carefully researched. Moreover, the dynamic characteristics of plasma were studied at different laser focusing depths. Research has found that the morphological changes of plasma are relatively stable, without significant changes, despite varying depths of laser focus on the sample surface. In addition, it was found that stable elemental emission spectra can always be obtained in the early plasma aggregation region. [ABSTRACT FROM AUTHOR]

A key challenge in quantum photonics today is the efficient and on-demand generation of high-quality single photons and entangled photon pairs. In this regard, one of the most promising types of emitters are semiconductor quantum dots, fluorescent nanostructures also described as artificial atoms. The main technological challenge in upscaling to an industrial level is the typically random spatial and spectral distribution in their growth. Furthermore, depending on the intended application, different requirements are imposed on a quantum dot, which are reflected in its spectral properties. Given that an in-depth suitability analysis is lengthy and costly, it is common practice to pre-select promising candidate quantum dots using their emission spectrum. Currently, this is done by hand. Therefore, to automate and expedite this process, in this paper, we propose a data-driven machine-learning-based method of evaluating the applicability of a semiconductor quantum dot as single photon source. For this, first, a minimally redundant, but maximally relevant feature representation for quantum dot emission spectra is derived by combining conventional spectral analysis with an autoencoding convolutional neural network. The obtained feature vector is subsequently used as input to a neural network regression model, which is specifically designed to not only return a rating score, gauging the technical suitability of a quantum dot, but also a measure of confidence for its evaluation. For training and testing, a large dataset of self-assembled InAs/GaAs semiconductor quantum dot emission spectra is used, partially labelled by a team of experts in the field. Overall, highly convincing results are achieved, as quantum dots are reliably evaluated correctly. Note, that the presented methodology can account for different spectral requirements and is applicable regardless of the underlying photonic structure, fabrication method and material composition. We therefore consider it the first step towards a fully integrated evaluation framework for quantum dots, proving the use of machine learning beneficial in the advancement of future quantum technologies. [ABSTRACT FROM AUTHOR]

Background: Trees have developed a broad spectrum of molecular mechanisms to counteract oxidative stress. Secondary metabolites via phenolic compounds emblematized the hidden bridge among plant kingdom, human health, and oxidative stress. Although studies have demonstrated that abiotic stresses can increase the production of medicinal compounds in plants, research comparing the efficiency of these stresses still needs to be explored. Thus, the present research paper provided an exhaustive comparative metabolomic study in Dalbergia odorifera under salinity (ST) and waterlogging (WL). Results: High ST reduced D. odorifera's fresh biomass compared to WL. While WL only slightly affected leaf and vein size, ST had a significant negative impact. ST also caused more significant damage to water status and leaflet anatomy than WL. As a result, WL-treated seedlings exhibited better photosynthesis and an up-regulation of nonenzymatic pathways involved in scavenging reactive oxygen species. The metabolomic and physiological responses of D. odorifera under WL and salinity ST stress revealed an accumulation of secondary metabolites by the less aggressive stress (WL) to counterbalance the oxidative stress. Under WL, more metabolites were more regulated compared to ST. ST significantly altered the metabolite profile in D. odorifera leaflets, indicating its sensitivity to salinity. WL synthesized more metabolites involved in phenylpropanoid, flavone, flavonol, flavonoid, and isoflavonoid pathways than ST. Moreover, the down-regulation of L-phenylalanine correlated with increased p-coumarate, caffeate, and ferulate associated with better cell homeostasis and leaf anatomical indexes under WL. Conclusions: From a pharmacological and medicinal perspective, WL improved larger phenolics with therapeutic values compared to ST. Therefore, the data showed evidence of the crucial role of medical tree species' adaptability on ROS detoxification under environmental stresses that led to a significant accumulation of secondary metabolites with therapeutic value. [ABSTRACT FROM AUTHOR]

Near-infrared (NIR)-emitting phosphors with broadband absorption from ultraviolet to visible light have been considered significant spectral converter materials for solar cells. In this work, NIR phosphor Zn3Ga2GeO8 (ZGGO):Cr3+,Yb3+ spinel solid solutions were synthesized using the classical high-temperature solid-state method. With an increase in the doping concentration of Cr3+ ions in ZGGO:Cr3+,Yb3+, a more distorted octahedron appeared around Cr3+ ions, which increased crystal field splitting. This process was accompanied with a broadening of NIR emission from Cr3+ 4T2 → 4A2 transition and enlarged the overlap area between the absorption spectrum of Yb3+ and the emission spectrum of Cr3+, resulting in an efficient energy transfer between Cr3+ and Yb3+. In the case of high-concentration Cr3+ doping, the near-infrared luminescence intensity of Yb3+ was more than 8 times that of low-concentration doped Cr3+. Therefore, it is proposed that the Cr3+,Yb3+ co-doped ZGGO phosphor is a potential spectral convert materials for silicon-based solar cells and thereby improves photovoltaic conversion efficiency. [ABSTRACT FROM AUTHOR]

Organoboron compounds offer a new strategy to design optoelectronic materials with high fluorescence efficiency. In this paper, the organoboron compound B‐BNBP with double B←N bridged bipyridine bearing four fluorine atoms as core unit is facilely synthesized and exhibits a narrowband emission spectrum and a high photoluminescence quantum yield (PLQY) of 86.53 % in solution. Its polymorphic crystals were controllable prepared by different solution self‐assembly methods. Two microcrystals possess different molecular packing modes, one‐dimensional microstrips (1D‐MSs) for H‐aggregation and two‐dimensional microdisks (2D‐MDs) for J‐aggregation, owing to abundant intermolecular interactions of four fluorine atoms sticking out conjugated plane. Their structure‐property relationships were investigated by crystallographic analysis and theoretical calculation. Strong emission spectra with the full width at half maximum (FWHM) of less than 30 nm can also be observed in thin film and 2D‐MDs. 1D‐MSs possess thermally activated delayed fluorescence (TADF) property and exhibit superior optical waveguide performance with an optical loss of 0.061 dB/μm. This work enriches the diversity of polymorphic microcrystals and further reveals the structure‐property relationship in organoboron micro/nano‐crystals. [ABSTRACT FROM AUTHOR]

An experimental study on the packing thickness (PT) dependent plasma emission caused by laser ablating thin-layer microgranular samples in air was conducted using three sets of size-selected copper grains (median size d50 = 53 mm, 72 mm, and 100 mm, respectively). For each size-selected case, the PT parameter was tuned from 0.15 to 1.00 mm through varying the amount of grains packed into a vessel with a steel bottom wall and the emission spectra of laser-induced plasma were measured at various PT. It is found that there is a striking threshold phenomenon in the measured behavior of PTdependent plasma emission. Specifically, when PT is less than a threshold PTth, the emission intensity exhibits an exponential decreasing with incremental thickness; however, when it exceeds PTth, the emission intensity becomes almost constant. It is also found that the PTth slightly depends on grain size but the ratio of PTth to d50 seems to be size independent. Combining the mechanical fundamentals of granular materials, we interpreted the findings by considering a PT-dependent effect of the vessel's bottom on the formation circumstance of a laser-induced plasma. This work has practical significance in assessing a threshold thickness above which laser-induced breakdown spectroscopy, as an analytical technique to quantify elements embedded in microgranular materials, is viable regardless of PT difference. [ABSTRACT FROM AUTHOR]

This study describes the rational development and synthesis of a benzothiazole-salicylaldehyde Schiff base probe 1. This probe is designed to function as a ratiometric fluorescent probe specifically for detecting ClO− ions, utilizing the imine bond as the fluorophore unit. Upon interaction with ClO− ions, probe 1 exhibits a redshift in its absorption spectrum from 435 nm to 450 nm. Moreover, in its emission spectrum, there is a ratiometric emission enhancement observed at 610 nm, providing a clear indication of the presence of ClO− ions. The sensitivity of probe 1 for detecting ClO− ions is quantified, revealing a lowest detection limit of 5.5 μM, indicating its potential for sensitive detection even at low concentrations of ClO− ions. Additionally, it has been successfully utilized for biological imaging purposes, demonstrating low cytotoxicity, which is crucial for its applicability in biological systems. [ABSTRACT FROM AUTHOR]

A ground-based 110 GHz radiometer was designed to measure the stratospheric ozone vertical profile by observing the 110.836 GHz ozone emission spectrum and the instrument has been operational at Sookmyung Women's University (37.54° N, 126.97° E) in Seoul, Korea. In this paper, we detail the instrumental design, calibration procedures, correction methods, and the retrieved ozone vertical profile. The instrument is a heterodyne total power radiometer. It down-converts the observed 110.836 GHz ozone frequency to 0.609 GHz, with a frequency resolution of 61 kHz and a bandwidth of 800 MHz. The spectral intensity is digitized using a fast Fourier transform spectrometer. For hot-cold calibration, we use microwave absorbers at room temperature and liquid nitrogen as calibration targets. Tropospheric opacity is corrected using the continuous tipping curve calibration. The measured opacities were compared with simulated values from the Korea Local Analysis and Prediction System (KLAPS) data. Additionally, since 2016, the stratospheric ozone profiles over Seoul have been demonstrated for the vertical range of 100 hPa – 0.3 hPa (16 km–70 km) with validation performed by comparing them to the ozone profiles from the MLS on AURA satellite. [ABSTRACT FROM AUTHOR]

The National Transportation Noise Map predicts time-averaged road traffic noise across the continental United States (CONUS) based on annual average daily traffic counts. However, traffic noise can vary greatly with time. This paper outlines a method for predicting nationwide hourly varying source traffic sound emissions called the Vehicular Reduced-Order Observation-based Model (VROOM). The method incorporates three models that predict temporal variability of traffic volume, predict temporal variability of different traffic classes, and use Traffic Noise Model (TNM) 3.0 equations to give traffic noise emission levels based on vehicle numbers and class mix. Location-specific features are used to predict average class mix across CONUS. VROOM then incorporates dynamic traffic class mix data to obtain dynamic traffic class mix. TNM 3.0 equations then give estimated equivalent sound level emission spectra near roads with up to hourly resolution. Important temporal traffic noise characteristics are modeled, including diurnal traffic patterns, rush hours in urban locations, and weekly and yearly variation. Examples of the temporal variability are depicted and possible types of uncertainties are identified. Altogether, VROOM can be used to map national transportation noise with temporal and spectral variability. [ABSTRACT FROM AUTHOR]

Here, we report on a simplified laser frequency noise measurement technique employing an acousto-optic modulator, a delay line, and a real-time oscilloscope. The technique is a slight modification of the typical delayed heterodyne method. Instead of using a swept frequency spectrum to analyze the laser emission spectrum, the waveform captured on a real-time oscilloscope is used to directly calculate the laser frequency noise. The oscilloscope bandwidth and sampling requirements can be kept modest by choosing a modulator driven at a few hundred megahertz, making this technique attractive for a large number of laboratories. We show the frequency noise measurements of two different lasers with linewidths at 2.7 kHz and 2 MHz. We took the opportunity to investigate the noise floor of the frequency noise measurement system, and we found that the noise floor of the frequency noise measurement depends on the power level of the laser that is being characterized, with the kilohertz linewidths laser requiring more power to reduce the noise floor to acceptable levels. [ABSTRACT FROM AUTHOR]

This paper reports the optical characterization of a controlled atmospheric-pressure dielectric barrier discharge (DBD) plasma source in air and Ar environments. In this study, Ar flow rate is held constant at 1 L/min while the operating voltages varied from 6.5 kV to 12.7 kV. Under these conditions, a calibrated commercial compact spectrometer covering the range from 200 to 850 nm was used to record the emission spectra of DBD plasma operating at different voltages, gap distances, and gas types. Using the Boltzmann distribution, we calculated the electron density ( $ n_e $ ne) and excitation temperatures in the plasma of air and Ar DBD at 2 mm gap distance . The emission spectra lines of the hydroxyl radicals (OH), $ {{N_{2}}} $ N2, and Ar ions are acquired at different operating conditions. According to the findings, the light intensity of Ar DBD is significantly higher than that of air DBD under the same conditions of operation. The intensity of the generated plasma spectrum is also shown to rise with both an increase in the input voltage and a decrease in the gap distance. The measurements also showed that the average temperature of the excited electrons is around 1.1 eV for air DBD and 0.11 eV for Ar DBD, while $ n_e $ ne for both is on the order of $ {10^{16}}\,{{\rm cm}^{-3}} $ 1016cm−3. These results show that as the working voltage increases, the plasma changes from a filamentary state to a homogeneous mode. Knowing the DBD parameters increases its chance to compete with traditional methods in many fields, such as water, polymers, and biomedical treatments. [ABSTRACT FROM AUTHOR]

Development of multifunctional organic materials is an area of intense research interest in organic materials chemistry. This study reports the synthesis, crystal structure elucidation and investigation of multiple properties of E-3-pyridylvinyl benzoxazole (3-PVBO) and its methylated analogue, 3-MPVBO. With Z′ = 2, 3-PVBO belongs to a rare class of crystals for which Z′ > 1. Upon methylation, fascinating material properties were observed. [3-MPVBO]I exhibited strong emission spectra and readily available redox states. It exhibited stronger emission at 474 nm, with a larger Stokes shift of 8900 cm−1, than the emission of 3-PVBO at 386 nm, with a Stokes shift of 5450 cm−1. Upon exposure to UV light, crystals of 3-PVBO underwent a solid-state photodimerization reaction in a head-to-tail fashion (HT), leading to the formation of the HT-rctt isomer of the dimer, i.e., 1,3-bis(benzoxazole)-2,4-bis(3-pyridyl)cyclobutane (PBOCB). Herein, the crystal structure, solid-state photoreactivity, and multiple material properties, e.g., photophysical and electrochemical properties, are presented. [ABSTRACT FROM AUTHOR]

With the increasing performance demand from the display market, it has become ever more important to realize wide color gamut requirement. In this paper, we fabricated a series of pTSF green devices, the optimal devices which exhibit excellent performance in the range of CIEx 0.17‐ 0.22, with the central color point meeting Adobe's green light requirements, showing the advantages in wide color gamut. Additionally, they have comparable performance to existing phosphporescent devices under DCI‐P3 light color, showing the advantages of high performance and high color purity. [ABSTRACT FROM AUTHOR]

We report the synthesis, structures, and magnetic and luminescence properties of a series of new monoand dinuclear Er3+ complexes derived from sterically demanding aryloxide and fluorinated alkoxide ligands: [4-tBu-2,6-(Ph2CH)2C6H2O]3Er(THF) (1), [(C6F5)3CO]3Er(Me3SiOH) (2), [(C6F5)3CO]3Er[(Me3Si)2NH] (3), [(C6F5)3CO]3Er(C6H5CH3) (4), [(C6F5)3CO]3Er(o-Me2NC6H4CH3) (5) and {[Ph(CF3)2CO]2Er(μ²-OC (CF3)2Ph)}2 (6). In compounds 1, 2, and 4, the Er3+ ion is four-coordinated and adopts a distorted trigonal pyramidal geometry, while in 3, 5, and 6, the coordination geometry of Er3+ is impacted by the presence of several relatively short Er...F distances, making them rather 6-coordinated. All compounds behave as field-induced Single Molecule Magnets (SMMs) and exhibit an Er3+ characteristic near infrared (NIR) emission associated with the 4I13/2 → 4I15/2 transition with a remarkably long lifetime going up to 73 µs, which makes them multifunctional luminescent SMMs. The deconvolution of the NIR emission spectra allowed us to provide a direct probe of the crystal field splitting in these compounds, which was correlated with magnetic data. [ABSTRACT FROM AUTHOR]

Developing a single-phase white emitting nanophosphor with high quantum efficiency has become a hotspot for scientific world. Herein, single-phase white-light emitting Zn1-x O:xDy3+ nanophosphors have been synthesized via a sonochemical method. X-ray diffraction analysis and Raman spectroscopy-based investigations confirmed the hexagonal wurtzite phase for Zn1-xO:xDy3+ nanophosphors with preferential growth along the (101) plane. Scanning electron microscopy images showed the formation of a ribbonshaped morphology with a diameter of ~25 nm. The emission spectra of the Dy3+-activated ZnO nanophosphors exhibited three distinct peaks, namely blue (480 nm), yellow (572 nm), and red (635 nm) emissions, under near-UV excitations related to the 4F9/2 → 6HJ (J = 15/2, 13/2, and 11/2) transitions of Dy3+ ions. The values of CIE chromaticity coordinates for the optimized phosphor (x = 0.329, y = 0.334) with correlated color temperature (CCT) of 5657 K indicated cool white-light emission from the phosphor. The thermal stability of ZnO:Dy3+ nanophosphors was probed by temperature-dependent luminescence. Quantitative evaluation of Judd-Ofelt intensity parameters, radiative parameters, luminescence decay, and quantum efficiency of Zn1-xO:xDy3+ using the J-O theory suggests that these nanophosphors are promising luminescent media for commercial white LEDs and other display devices. [ABSTRACT FROM AUTHOR]

The paper presents a description of a device for studying the emission spectra of phosphors for laser lighting systems when they are affected by laser radiation with λ = 405–450 nm with different values of power and current. The scheme of the device driver and its component base is described in detail. When using a laser device, the authors of the work obtained the values of the luminous flux depending on various values of current and electric power. The use of a thermal imager made it possible to register the thermal fields formed during this kind of impact. Based on the results of the work, it was concluded that the design of a laser device with adjustable current strength and electrical power obtained in the course of the work makes it possible to carry out various applied scientific research related to the study of the effect of laser radiation on matter. [ABSTRACT FROM AUTHOR]

In the paper, we demonstrate the application of X-ray spectroscopy with high spatial resolution to study magnetic reconnection in laboratory astrophysical experiments performed with nano- and pico-second duration laser facilities at a moderate laser density on the target of <1018 W/cm2. A brief overview of the commonly used experimental schemes is given. Atomic kinetic calculations for the L-shell spectra of Ne- and F‑like Fe ions (iron, Z = 26) demonstrate the high sensitivity of the measurements to changes in plasma parameters. The scope of the different diagnostic approaches to measure electron temperature and laser plasma density is discussed. It is shown that transitions in Ne-like ions are a universal tool for measuring plasma parameters, both in the region of laser interaction with the target and in the reconnection zone. [ABSTRACT FROM AUTHOR]

With the increasing performance demand from the display market, it has become ever more important to realize wide color gamut requirement. In this paper, we fabricated a series of pTSF green devices, the optimal devices which exhibit excellent performance in the range of CIEx 0.17‐0.22, with the central color point meeting Adobe's green light requirements, showing the advantages in wide color gamut. Additionally, they have comparable performance to existing phosphporescent devices under DCI‐P3 light color, showing the advantages of High Performance and High Color Purity [ABSTRACT FROM AUTHOR]

We explore the application of artificial neural networks (ANNs) for predicting plasma temperatures in Laser-Induced Breakdown Spectroscopy (LIBS) analysis. Estimating plasma temperature from emission spectra is often challenging due to spectral interference and matrix effects. Traditional methods like the Boltzmann plot technique have limitations, both in applicability due to various matrix effects and in accuracy owing to the uncertainty of the underlying spectroscopic constants. Consequently, ANNs have already been successfully demonstrated as a viable alternative for plasma temperature prediction. We leverage synthetic data to isolate temperature effects from other factors and study the relationship between the LIBS spectra and temperature learnt by the ANN. We employ various post-hoc model interpretation techniques, including gradient-based methods, to verify that ANNs learn meaningful spectroscopic features for temperature prediction. Our findings demonstrate the potential of ANNs to learn complex relationships in LIBS spectra, offering a promising avenue for improved plasma temperature estimation and enhancing the overall accuracy of LIBS analysis. [ABSTRACT FROM AUTHOR]

This article describes the synthesis and crystal structure of ten new Tc(V) complexes with pyrazine containing homologous alkoxy ligands. We carried out an analysis of the Hirshfeld surfaces for the described compounds and found out that with increasing length of the hydrocarbon substituent from CH3 to C10H21 the percentage of H⋯H interactions in crystals increases from 28% to 59%. The purpose of this article was to show the pattern of increase in interplanar distances in crystals depending on the length of the hydrocarbon substituent, and also to study the thermochemical properties of Tc(V) complexes. The mechanism of thermolysis does not depend on the length of the hydrocarbon substituent and differs only in the temperature range of the reactions. The absorption bands of the obtained complexes in IR and UV-vis spectra do not depend on the length of the hydrocarbon substituent. Using a complex with a propyl substituent as an example, the UV-vis spectral data of the mother solution are presented. Based on DFT calculations of spectra and molecular models, an indirect identification of the reaction intermediate is provided. Using a complex with a methyl substituent as an example, data on MALDI spectrometry are presented. [ABSTRACT FROM AUTHOR]

Fluorescent polymeric materials have been exploited in the fields of aesthetical purposes, biomedical engineering, and three‐dimensional printing applications. While the fluorescent materials are prepared by the polymerization of fluorescent monomer or the blending a fluorescent dye with common polymer, the covalent immobilization of fluorescent dye onto common polymers is not the practical technique. In this paper, dansylated nitrile N‐oxide (Dansyl‐NO) has been designed and synthesized to be a stable nitrile N‐oxide as the derivative of 2‐hydroxy‐1‐naphthaldehyde. While Dansyl‐NO shows good reactivity to an alkene and an alkyne to give fluorescent Dansyl‐Ene and Dansyl‐Yne, respectively, it hardly reacts to a nitrile. The results indicate that Dansyl‐NO serves as a fluorescent dye clickable to alkenes and alkynes. To know the effects of solvent on the fluorescent properties, the UV‐vis and fluorescence spectra of Dansyl‐Ene are measured in three solvents. Dansyl‐Ene shows fluorescent solvatochromism, which appears to be red‐shifted along with the increase in solvent polarity. Poly(styrene‐co‐butadiene) directly reacts with Dansyl‐NO to give fluorescent modified SB. The emission spectrum of modified SB is blue‐shifted compared with that of Dansyl‐Ene. The blue‐shift could be possibly attributed to the presence of less polar polymer skeleton around the dansyl moieties of modified SB. [ABSTRACT FROM AUTHOR]

Cyan phosphors are urgently needed to fill the cyan gap and improve the spectral continuity of white light-emitting diodes (LEDs) to cater to the high demand for high-quality lighting. Here, a series of new Eu2+-activated La3Si6.5Al1.5N9.5O5.5 (LSANO) cyan phosphors were prepared, and their luminescence properties and color centers were analyzed through fluorescence spectral measurements from 7 K to 475 K. At 300 K, the photoluminescence excitation (PLE) spectrum monitored at 483 nm presents a broadband of 200–460 nm with a peak at 398 nm, matching well with commercial violet LED chips. When excited by 398 nm violet light, the photoluminescence emission (PL) spectrum of LSANO:0.01Eu2+ exhibits a cyan emission band at about 483 nm. At 7 K, the emission spectrum clearly shows an asymmetric emission band and the emission peak wavelength changes from 483 nm (300 K) to 500 nm (7 K), indicating that there are two possible color centers in the LSANO:Eu2+ phosphor. Moreover, the maximum emission value can be adjusted from 480 to 499 nm by adjusting the doping content of Eu2+. Finally, a violet-chip-based white LED with the optimized color quality of Ra = 91.4, Rf = 90.1, and Rg = 93.6 was fabricated by adding the prepared cyan phosphor, verifying the potential application of the prepared cyan phosphor LSANO:Eu2+ in high-quality white LEDs. [ABSTRACT FROM AUTHOR]

This paper describes the observed position dependent emission spectrum and vacuum ultraviolet (VUV) to clarify the optical structure of argon atmospheric pressure plasma jets (APJs). Visible emission spectra of argon, nitrogen, and OH molecules were measured as a function of position from the nozzle of plasma jet generator to gas flow direction. From the results, we realized that a certain electric field is required for producing high energy excited atoms of argon in the jet from the high voltage electrode in the device to the ground positioned at downstream side. Moreover, VUV was detected along the plasma jet through the downstream direction. Thus, we could picture that the light pattern of plasma jet of which intensity weaken depend to the distance from the nozzle is sustained by the above two factors with the present steady state experiments. [ABSTRACT FROM AUTHOR]

It is of great importance to develop new broadband red phosphors since they have possible applications like plant cultivation, indoor lighting and non-destructive sensing. Herein, we report a series of Eu2+, Mn2+ activated NaSrSc(BO3)2 phosphors via a conventional solid-state reaction route. It has been found that both Mn2+ and Eu2+ solo-doped NaSrSc(BO3)2 show weak or no luminescence, while Eu2+, Mn2+ co-doped NaSrSc(BO3)2 exhibits wide-band absorption and intense deep-red emission at 680 nm with color purity of 89%. Analysis of the absorption, excitation and emission spectra of Eu2+, Mn2+ solo- and co-doped NaSrSc(BO3)2 indicates that this deep-red broadband emission originates from Eu2+ sensitization of the octahedron Mn2+ 4T1–6A1 transition. It was found that the photoionization process led by energetic similarity of the host band-gap and the Eu2+ lowest 5d excited state was mainly responsible for the vanished luminescence of Eu2+. The values of internal quantum efficiency (IQE) and absorption efficiency (AE) for the optimal NSSO:0.007Eu2+,0.05Mn2+ sample are 24.5% and 61.8%, respectively. This work could provide new insights into exploring novel Mn-activated deep-red luminescent materials. [ABSTRACT FROM AUTHOR]

Two new spiroacridine-imidazole derivatives (SAF-BI and SAF-PI) with narrow deep-blue emission spectrum were synthesized by incorporating a spiroacridine donor unit with benzimidazole and phenanthroimidazole acceptors via the Buchwald–Hartwig cross coupling reaction, respectively. Their photophysical and electrochemical properties, based on theoretical calculations and experimental measurements, as well as thermal stabilities and organic electroluminescence properties were systematically investigated. These compounds exhibited a strong deep-blue emission (ca. 410 nm) with full-width at half maximum (FWHM) of less than 55 nm in toluene solution and a blue emission (ca. 440 nm) in solid films, and the theoretical singlet–triplet energy splittings (ΔEST) were calculated to be 0.05 eV for SAF-BI and 0.38 eV for SAF-PI. The doped devices with a structure of ITO/PEDOT:PSS (30 nm)/mCBP:SAF derivative (x wt%) (30 nm)/BmPyPB (35 nm)/Liq (2 nm)/Al (200 nm) were fabricated using solution-processed emitting layers to investigate their electroluminescence (EL) performances, in which the doped devices of SAF-BI exhibited a deep-blue emission with an EQEmax of 1.81% and an Lmax of 352 cd m−2, and its Commission Internationale de l′Eclairage (CIE) coordinates were (0.17, 0.07). [ABSTRACT FROM AUTHOR]

A coma-free superhigh spectral resolution optical spectrometer was successfully designed and constructed for practical application. The spectrometer consisted of 20 subgratings and a 2D BSI-CMOS array detector. The spectra were 20-fold with the physical size of the photoelectron detection along the diffraction direction and extended by a factor of 20 to achieve a spectral resolution of 0.01 nm per pixel without any moving parts. Ultrahigh dense emission lines of a hollow cathode Fe lamp were measured. Based on the data analysis and discussions, among the highly resolved spectral lines of Fe measured with an improved signal-to-noise ratio in the 170–600 nm spectral region, 2451 lines were identified in accordance with the reported ones in the literature; however, more than 1100 lines with lower intensity remained unassigned with an unknown mechanism of their origins. Our experimental data indicated the need to more fundamentally study and explore the spectral data of the Fe atoms with the potential for broad application prospects for Fe-based materials in the future. [ABSTRACT FROM AUTHOR]

Two types of developments for very accurate non‐adiabatic corrections to rovibrational molecular energy levels, one of a formal nature and the other of a heuristic nature, lead to fundamentally different approaches for effective nuclear masses. The former yields effective masses that have non‐physical interpretation at some ranges of nuclear distances. The later uses physical masses obtained from electronic structure calculations. This paper contains a brief review of the subject and proposes procedures to improve and generalize the heuristic approach. Comparisons are made of the results obtained by the two approaches for the H2 molecule, since no further calculations were found with the proper accuracy, but some issues involving the HeH+ ion and the water molecule are discussed. The conclusion is that the heuristic approach has many advantages over the formal one, namely, equivalent accuracy and physically grounded qualitative interpretation. But, moreover, it seems to be presently the only method that allows non‐adiabatic calculations for well isolated states of larger molecules. [ABSTRACT FROM AUTHOR]

• Heterojunction models consisting of stacked semiconductor monolayer and half-metallic monolayers is designed. • The MoSi 2 N 4 /ScSi 2 N 4 heterojunction has robust half-metallic behavior and tensile anisotropy at equilibrium. • The physical properties of MoSi 2 N 4 /ScSi 2 N 4 heterojunction can be modulated. Heterojunctions formed by stacking different two-dimensional monolayer materials typically have tunable electronic properties, which will greatly broaden the application prospects of 2D materials in electron devices. In this paper, the structures, electron properties, and anisotropy of MoSi 2 N 4 /ScSi 2 N 4 heterojunctions formed by stacking MoSi 2 N 4 monolayer with semiconductor properties and ScSi 2 N 4 monolayer with half-metallic properties have been systematically studied. The results show that Type-Ⅰ configuration has the most stable structure in terms of total energy, binding energy, phonon spectrum and molecular dynamics among the three configurations formed by MoSi 2 N 4 /ScSi 2 N 4 heterojunctions. The MoSi 2 N 4 /ScSi 2 N 4 heterojunction has robust half-metallic behavior and tensile anisotropy at equilibrium. At the same time, MoSi 2 N 4 /ScSi 2 N 4 heterojunction can still maintain stable ferromagnetic and half-metallic properties under large interlayer distance changes. Studies of magnetic anisotropy show that the direction of hard axis for MoSi 2 N 4 /ScSi 2 N 4 heterojunction is perpendicular to the 2D layer plane. The tunable properties of MoSi 2 N 4 /ScSi 2 N 4 heterojunction provides promising exploration for novel 2D materials. [ABSTRACT FROM AUTHOR]

In this paper, Lu 2.97 Al 5–x Ga x O 12 :Ce 0.03 (x = 0, 1, 2, 3) nanophosphors were synthesized using sol-gel method and calcined at 1100 °C for 3 h. The effect of Ga content on the structural, photoluminescence (PL), and notably thermoluminescence (TL) glow curve, dose response, repeatability and fading properties were investigated. X-ray diffraction (XRD) results indicated that all synthesized samples were crystallized in a pure garnet phase. The PL emission spectra exhibited a broad emission band corresponding to the 5 d → 4f (2F 5/2 , 2F 7/2) transition of Ce3+ ions in the garnet lattice. Furthermore, a significant decrease in emission intensity was observed upon increasing Ga content. The TL characteristics of nanopowders irradiated with β-rays revealed a significant effect of Ga content on the peak position, shape and intensities of TL Glow curves, which can be explained by the reduction of the energy gap and the distribution of trap levels. The dose response linearity in the range of 0.125–100 Gy was examined for different Ga content, revealing a good linear behavior for x = 0 and 1 Ga. Additionally, samples prepared with x = 0, 1, and 2 Ga exhibited a high level of repeatability across a batch of 10 samples. Also, fading studies were performed for 128 h and revealed strong fading in samples synthesized with x = 0 and 1 Ga. These results suggest potential applications of Lu 3 Al 5 O 12 :Ce and Lu 3 Al 4 Ga 1 O 12 :Ce in ionizing radiation dosimetry. • Lu 3 Al 5-x Ga x O 12 :Ce3+ (x = 0, 1, 2 and 3) nanophosphors were successfully synthesized using sol–gel method. • Thermoluminescence properties of prepared nanophosphors exhibited a strong dependence on Ga content. • Single garnet phase was obtained for all prepared nanophosphors. • Lu 3 Al 5-x Ga x O 12 :Ce 0.03 demonstrated a good linear behavior within the range 0.125–100 Gy for x = 0 and x = 1. • Nanophosphors prepared with Ga content of x = 0 and x = 1 displayed perfect repeatability and indicated a remarkably strong fading. [ABSTRACT FROM AUTHOR]

This paper employs first-principles methods to compute the stability, electrical properties, and optical properties of the GaN/Sc 2 CF 2 heterostructure and investigates its photoelectric effect by constructing a photodetector device. The GaN/Sc 2 CF 2 heterostructure has been found to be an indirect bandgap semiconductor with a bandgap value of 1.836 eV, and its substantial stability has been determined through phonon spectrum and molecular dynamics calculations. A charge transfer occurs in the GaN/Sc 2 CF 2 heterostructure, resulting in the formation of an internal electric field directed from the Sc 2 CF 2 layer to the GaN layer. Compared to single-layer GaN and Sc 2 CF 2 , the GaN/Sc 2 CF 2 heterostructure has a wider absorption spectrum and enhanced light absorption in the visible light range. For the GaN/Sc 2 CF 2 photodetector, it exhibits high photocurrent and extinction ratio, demonstrating favorable photoresponse characteristics, and it is more sensitive to changes in the polarization angle along the armchair direction. This research provides theoretical basis and research ideas for the photogalvanic detection capability of GaN/Sc 2 CF 2 van der Waals heterostructures, offering a promising candidate material for photodetectors. [Display omitted] • The electronic properties and photogalvanic effect of GaN/Sc 2 CF 2 heterojunction were studied using first principles calculations. • Compared with GaN monolayer and Sc 2 CF 2 monolayer, GaN/Sc 2 CF 2 heterojunctions have smaller band gap and better light absorption coefficient. • The GaN/Sc 2 CF 2 photodetector exhibits excellent polarization sensitivity. [ABSTRACT FROM AUTHOR]

The impact of plasma temperature on the formation and evolution of distinct and unique molecular species recorded as molecular signatures from laser induced plasma (LIP) was examined in this study. A definitive correlation between plasma temperature and the formation of molecular species has been established through a comprehensive temporal analysis of BO and BO2 molecular bands. The utilization of the signal-to-envelope ratio diagrams allowed for pinpointing the optimal temperature range for molecule emission. Notably, the molecule BO exhibited an ideal temperature range of 10,000–11,000 K for the proper formation of molecular emission bands, while BO2 preferred temperatures between 8,000–9,000 K. These optimal temperature ranges remained consistent regardless of the laser irradiation wavelength or ambient gas conditions of Ar, air or He studied in this work. These key findings highlight the significant influence of plasma temperature in shaping the molecular species observed in LIP. [ABSTRACT FROM AUTHOR]

Single artificial opal films, grown by the method of vertically moving meniscus and characterized by the reflection spectroscopy technique, have been impregnated with the Eu(CH3COO)3·xH2O salt. The influence of glycerol, embedded additionally in opal pores to reduce the dielectric contrast, on the europium (III) emission spectrum has been investigated. The effect of local heating of the emitting substance in opal pores under laser excitation is also discussed. [ABSTRACT FROM AUTHOR]

FU Ori– and EX Lup–type objects present natural experiments for understanding a critical stage in the star and planet formation process. These objects offer insight into the diversity of molecules available to forming planetary systems due to a sudden increase in accretion, and central luminosity causes the disk and surrounding material to increase in temperature. This allows for volatiles to sublimate off of grains and exist in the gas phase for tens to hundreds of years after initial outburst. While this dynamic stage may be common for solar-type protostars, observations of the chemical impact of these bursts are rare. In this article, we present observations from the NOrthern Extended Millimeter Array of five young stellar objects (YSOs) that have undergone outbursts within the past 100 yr and catalog the volatile chemistry found within ∼1000 au of the YSO. Only one source clearly shows a line-rich spectra with >11 molecules detected, including complex organics and water, as is expected for a spectra signature for a postoutburst source. This source is V1057 Cyg, and we present it as the northern analog to the well-studied and molecule-rich FU Ori source, V883 Ori. Our conclusions on the chemical inventory of the other four sources in our sample are sensitivity limited, as V1057 Cyg contains the highest disk/envelope gas mass. [ABSTRACT FROM AUTHOR]

Optically pumped spintronic terahertz emitters (STEs) have, in less than a decade, strongly impacted terahertz (THz) source technology, by the combination of their Fourier‐limited ultrafast response, their phononless emission spectrum and their wavelength‐independent operation. However, the intrinsic strength of the inverse spin Hall effect governing these devices introduces a challenge: the optical‐to‐terahertz conversion efficiency is considerably lower than traditional sources. It is therefore primordial to maximize at least their electromagnetic efficiency independently of the spin dynamics at play. Using a rigorous time‐domain treatment of the electromagnetic generation and extraction processes, an optimized design is presented and experimentally confirmed. With respect to the strongest reported spintronic THz emitters it achieves a 250% enhancement of the emitted THz field and therefore an 8 dB increase of emitted power. This experimental achievement brings STE close to the symbolic barrier of mW levels. The design strategy is generically applicable to any kind of ultrafast spin‐to‐charge conversion (S2C) system. On a broader level, our work highlights how a rigorous handling of the purely electromagnetic aspects of THz spintronic devices can uncover overlooked aspects of their operation and lead to substantial improvements. [ABSTRACT FROM AUTHOR]

In this work, two different composite nanostructures, YAG:Ce and Ga0.9In0.1N, were prepared by the Urea Glass Route method and tested for the production of white light. The first composite was prepared by synthetizing the Ga0.9In0.1N nanoparticles in the presence of YAG:Ce nanoparticles. The second one was prepared by synthetizing YAG:Ce nanoparticles in the presence of Ga0.9In0.1N nanoparticles. These systems can be useful for the production of white light. X-ray Diffraction and Transmission and Scanning Electron Microscopies (TEM and SEM) were used to evaluate their structural and morphological properties. Excitation and emission spectra, the quantum yield and colour of the emitted light were acquired to evaluate the optical properties of the systems. [ABSTRACT FROM AUTHOR]

Electrically conducting polymers are increasingly being used as NIR fluorescence probes in the area of biomedical engineering via the application of a structural modification process. Peroxydisulphate (PDS) initiated the chemical polymerization process of anthranilicacid (AnA) in a nitrogen atmosphere at a temperature of 0–5 °C. Rosebengal (RB) was used as an end capping agent, and vigorous stirring was maintained with and without sand. The produced polymer and its nanocomposite were examined using instruments for UV–visible, TGA, DSC, SEM, EDX, FTIR, CV, FES, HRTEM, and XRD. The thermal stability of the resulting polymers was investigated using non-isothermal degradation kinetics. Additionally, the thermodynamic parameter values were determined. In the 3% weight Sand loaded PAnA system, a conductivity value of 4.31 × 10−2 S/cm was recorded, signifying a 90.3% yield percentage. Sand was added, and this resulted in an increase in the rate of polymerization (Rp) of anthranilicacid to 1.8 × 10–4 mol/lit/sec. A peak at 507 cm−1 in the FTIR spectrum confirmed the metal-oxide stretching of nano Sand. The PAnA/sand nanocomposite system has a higher photo-conversion efficiency of 1.49 percent as compared to the RB end capped PAnA system. The UV–visible spectrum and emission spectrum showed peaks around 750 nm. The experimental results are scrutinized closely and compared to values reported in the literature. [ABSTRACT FROM AUTHOR]

We study a quantum cone, a novel structure composed of multiple quantum dots with gradually decreasing diameters from the base to the top. The dot distribution leads to a dispersive radiated spectrum. The blue edge of the spectrum is determined by the quantum confinement of excitons on top of the cones, while the red edge is determined by the bandgap of a semiconductor. We observe the kinetics of photoluminescence by obeying the stretch-exponential law from quantum cones formed on the surface of diamond-like carbon (DLC). They are explained by an increase in the lifetime of excitons along the height of the cone from the top to the base of the cone and an increasing concentration of excitons at the base due to their drift in the quasi-built-in electric field of the quantum cone. The possible visualization of the quantum cone tops of DLC using irradiation by a UV light source is shown. A quantum cone is an innovative nano-source of light because it substitutes for two elements in a conventional spectrometer: a source of light and a dispersive element—an ultrafast monochromator. These features enable the building of a nano-spectrometer to measure the absorbance spectra of virus and molecule particles. [ABSTRACT FROM AUTHOR]