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The need for photosensors and gas sensors arises from their pivotal roles in various technological applications, ensuring enhanced efficiency, safety, and functionality in diverse fields. In this paper, interlinked PbS/Sb2O5 thin film has been synthesized by a magnetron sputtering method. We control the temperature to form the nanocomposite by using their different nucleation temperature during the sulfonation process. A nanostructured PbS/Sb2O5 with cross-linked morphology was synthesized by using this fast and efficient method. This method has also been used to grow a uniform thin film of nanocomposite. The photo-sensing and gas-sensing properties related to the PbS/Sb2O5 compared with those of other nanomaterials have also been investigated. The experimental and theoretical calculations reveal that the PbS/Sb2O5 exhibits extraordinarily superior photo-sensing and gas-sensing properties in terms of providing a pathway for electron transport to the electrode. The attractive highly sensitive photo and gas sensing properties of PbS/Sb2O5 make them applicable for many different kinds of applications. The responsivity and detectivity of PbS/Sb2O5 are 0.28 S/mWcm−2 and 1.68 × 1011 Jones respectively. The sensor response towards NO2 gas was found to be 0.98 at 10 ppb with an limit of detection (LOD) of 0.083 ppb. The PbS/Sb2O5 exhibits high selectivity towards the NO2 gas. Density functional theory (DFT) and time-dependent density functional theory (TD-DFT) were used to analyze the geometries, electronic structure, and electronic absorption spectra of a light sensor fabricated by PbS/Sb2O5. The results are very analogous to the experimental results. Both photosensors and gas sensors are indispensable tools that contribute significantly to the evolution of technology and the improvement of various aspects of modern life. [ABSTRACT FROM AUTHOR]

While cytochrome P450 (CYP; P450) enzymes are commonly associated with the metabolism of organic xenobiotics and drugs or the biosynthesis of organic signaling molecules, they are also impacted by a variety of inorganic species. Metallic nanoparticles, clusters, ions, and complexes can alter CYP expression, modify enzyme interactions with reductase partners, and serve as direct inhibitors. This commonly overlooked topic is reviewed here, with an emphasis on understanding the structural and physiochemical basis for these interactions. Intriguingly, while both organometallic and coordination compounds can act as potent CYP inhibitors, there is little evidence for the metabolism of inorganic compounds by CYPs, suggesting a potential alternative approach to evading issues associated with rapid modification and elimination of medically useful compounds. [ABSTRACT FROM AUTHOR]

In this work, the cadmium sulfide (CdS)/Perovskite/copper sulfide (CuS) film layers were fabricated via a chemical bath deposition, spin coating, and doctor blade methods. As-synthesized thin films are studied through standard characterization techniques such as X-ray diffraction (XRD), Raman spectroscopy, scanning electron microscopy (SEM) with EDAX, atomic force microscopy (AFM), and UV–visible spectroscopy. Structural properties were analyzed through XRD and Raman. The resulting optical energy bandgaps for CdS, perovskite, and CuS are 2.4 eV, 1.65 eV, and 2.3 eV, respectively. The morphological images of the samples are obtained from the SEM confirming their structures and from EDAX the elemental composition is verified. The measured surface roughness showed the increment as the layer-by-layer CdS/Perovskite/CuS structure fabricated, which somehow contributed to the enhancement of optoelectronic properties. The electrical and application-based properties were investigated through I-V characterization. The CdS/CuS bi-layer structure has been modified via the insertion of as-synthesized perovskite material. Moreover, the insertion of the perovskite layer between them has improved the photosensing performance. The improvement in the solar sensing performance is due to the perovskite properties such as rich charge carriers, narrow bandgap, and good conductivity, which makes it a good charge communicator in the CdS/CuS low-cost thin-film photosensor. [ABSTRACT FROM AUTHOR]

Amid the escalating global environmental concerns and energy demands, the synergistic remediation of these challenges through sustainable methodologies is paramount. Photocatalysis, a pivotal green technology, holds promise for energy evolution and pollutant degradation. We present a simple strategy for synthesizing CdS, MoS2, and CdS/MoS2 heterostructures via a cost-effective solution-based approach. The resultant materials exhibit hierarchical nanoarchitectures- nanoparticles, nanorods, and nanoflakes- controllable by solvent selection, such as water, ethylene glycol, and ethylenediamine, using l-cysteine, a natural source of sulfur, and demonstrate their photocatalytic performances. Employing density functional theory simulations, we corroborate experimental findings, unveiling structural evolution, band gap variation, and enhanced photocatalytic and photoresponsive properties. The CdS/MoS2 heterostructure demonstrates remarkable charge transfer and photoconductivity, stemming from van der Waals interactions and charge migration. This synergistic effect of charge transfers and lattice mismatch of these hybrid nanostructures manifests a substantially narrowed band gap, outperforming pristine counterparts, and substantiates exceptional photocatalytic and light-sensing performance. Our study advances morphology-driven photocatalysis, offering novel insights into green energy conversion. [ABSTRACT FROM AUTHOR]

Cyanobacteria are ancestors of chloroplast and perform oxygen-evolving photosynthesis similar to higher plants and algae. However, an obligatory requirement of photons for their growth results in the exposure of cyanobacteria to varying light conditions. Therefore, the light environment could act as a signal to drive the developmental processes, in addition to photosynthesis, in cyanobacteria. These Gram-negative prokaryotes exhibit characteristic light-dependent developmental processes that maximize their fitness and resource utilization. The development occurring in response to radiance (photomorphogenesis) involves fine-tuning cellular physiology, morphology and metabolism. The best-studied example of cyanobacterial photomorphogenesis is chromatic acclimation (CA), which allows a selected number of cyanobacteria to tailor their light-harvesting antenna called phycobilisome (PBS). The tailoring of PBS under existing wavelengths and abundance of light gives an advantage to cyanobacteria over another photoautotroph. In this work, we will provide a comprehensive update on light-sensing, molecular signaling and signal cascades found in cyanobacteria. We also include recent developments made in other aspects of CA, such as mechanistic insights into changes in the size and shape of cells, filaments and carboxysomes. [ABSTRACT FROM AUTHOR]

While cytochrome P450 (CYP; P450) enzymes are commonly associated with the metabolism of organic xenobiotics and drugs or the biosynthesis of organic signaling molecules, they are also impacted by a variety of inorganic species. Metallic nanoparticles, clusters, ions, and complexes can alter CYP expression, modify enzyme interactions with reductase partners, and serve as direct inhibitors. This commonly overlooked topic is reviewed here, with an emphasis on understanding the structural and physiochemical basis for these interactions. Intriguingly, while both organometallic and coordination compounds can act as potent CYP inhibitors, there is little evidence for the metabolism of inorganic compounds by CYPs, suggesting a potential alternative approach to evading issues associated with rapid modification and elimination of medically useful compounds.

A new architecture of photosensitive elements for the near- (0.7–1.4 μm) and short-wavelength (1.4–3.0 μm) infrared spectral ranges is proposed, which is based on hybrid nanostructures consisting of PbS colloidal quantum dots and ZnO and silver nanowire functional layers. Small-sized (12 × 12 μm) photosensitive elements with an energy barrier at the contact between layers of colloidal quantum dots with n- and p‑type conductivity have been studied. The I‒V characteristics, spectral dependences of optical absorption, and relative spectral photosensitivity Si(λ)/Si(λmax) of the barrier structures at room temperature have been examined. It is shown that the proposed architecture of the barrier structures ensures the photosensitivity in a wide spectral range from 0.4 to 2.0 µm. An excess of the average value of the relative spectral sensitivity Si(λ)/Si(λmax) by a factor of about 1.5 as compared with the values observed previously for the PbS colloidal quantum dot barrier nanostructures in the wavelength range of 0.9–1.85 μm has been found. [ABSTRACT FROM AUTHOR]

This report discusses about the improvement in photosensing characteristics of a silver (Ag) nanoparticles (NP) textured aluminum oxide (Al2O3) thin film (TF) device by glancing angle deposition (GLAD) technique. This device has been synthesized on n-Si substrates using an electron beam (e-beam) evaporation technique. The samples were then morphologically and crystallographically characterized by field emission scanning electron microscopy (FESEM), energy-dispersive X-ray spectroscopy (EDX), transmission electron microscopy (TEM), and X-ray diffraction (XRD), respectively. The Ag NP/Al2O3 TF-based device has a two fold improvement in photocurrent compared to the bare Al2O3 TF device owing to the generation of the interfacial trap states. The Ag NP/Al2O3 TF-based device also possessed 3.1 fold enhancement in photosensitivity, improved barrier height (0.80 eV), detectivity (3.7 × 107 jones), and noise equivalent power (NEP: 2.17 × 10−9 W). The Ag NP/Al2O3 TF device has faster photosensing performances (Tr = 0.25 s and Tf = 0.25 s) than the bare Al2O3 TF device (Tr = 0.60 s and Tf = 0.58 s). Therefore, the improved parameters will ensure that the Ag NP/Al2O3 TF device can be used as a fast-switching efficient photosensor. [ABSTRACT FROM AUTHOR]

In the present work, chemical bath deposition was employed at 80°C for the fabrication of pure and aluminum-substituted cadmium selenide thin films on glass substrate, with Al concentrations of 0–20%. x-ray diffraction and Raman spectroscopy were carried out to probe the structural properties of the thin films. In addition, the electronic structure and morphological and optical properties of the samples were systematically investigated by x-ray photoelectron spectroscopy (XPS), transmission electron microscopy (TEM), atomic force microscopy (AFM), UV–visible (UV–Vis) spectroscopy, and photoluminescence (PL) spectroscopy, respectively. XPS spectra were acquired to determine the surface composition of 15% and 20% Al-doped CdSe thin film, demonstrating the successful doping of Al, which was also confirmed from EDS spectra. The XPS spectra showed that the binding energy (BE) values were shifted toward the lower BE side for increasing Al content. The direct energy band estimated from UV–Vis and PL data revealed a blueshift for all thin films. Raman spectra recorded for the pure and Al-doped CdSe thin films exhibited the strongest first-order phonon modes at ~ 203 cm−1 features of CdSe nanostructure formation. The XRD pattern analyzed using Rietveld refinement revealed that pure and Al-doped CdSe were of a sphalerite cubic structure. TEM images revealed the formation of nanowires and agglomerated nanocrystals of pure CdSe and 5% Al-doped CdSe thin film, supported by the AFM micrographs. The 10% Al-doped CdSe thin-film-based photosensor exhibited higher responsivity (0.77 A/W) and specific detectivity ( 2.68 × 10 11 cm Hz1/2 W−1) than pure and 5% Al-doped CdSe thin film. [ABSTRACT FROM AUTHOR]

The features of the deviation of the open circuit potential at the semiconductor–electrolyte contact where cadmium and zinc sulfides are used as semiconductor materials are considered. Models of equivalent electrical circuits that explain the observed phenomena are proposed. Some examples of devices designed on the basis of the research results are given. [ABSTRACT FROM AUTHOR]

Digital cameras are widely used in artificial intelligent systems: machine vision, pattern recognition, automatic defect detection, etc. The quality of these systems is defined in significant degree by the registered images signal-to-noise ratio. Digital camera noise, conditions of shooting, low-light illumination decrease image quality. But information about camera noise allows to significantly improve it. However, noise characteristics are often absent in the instructions even for scientific digital cameras. There are various methods of photosensor noise measurement. They have different accuracy, speed of implementation and processing time. Therefore, the choice of the optimal method for measuring noise is of great interest. The paper presents the virtual camera-based analysis of methods of photosensor characterization. This technique determines the maximum and possible accuracy of the methods. Three methods of photosensor noise characterization are considered: the EMVA (European machine vision association) standard 1288, automatic segmentation of a non-uniform target (ASNT), and automatic segmentation of a striped target (ASST). The method's accuracy and processing time were estimated. [ABSTRACT FROM AUTHOR]

BackgroundLight is the primary synchronizing cue for the circadian timing system, capable of exerting robust physiological effects, even with very dim and/or brief photic exposure. Mammals, including humans, are particularly susceptible to light at night. As such, measures of light in the sleeping environment are critical for evaluating sleep health. Sleep diaries provide inexpensive measures of sleep, but do not typically include light information.MethodsFour questions probing visual perception of light in the bedtime and waking environments were added to the Consensus Sleep Diary for Morning administration. As part of a lighting intervention study, 18 hospital Labor and Delivery Department personnel completed the sleep diary for 1 week in each of two experimental conditions while wearing Actiwatch devices equipped with photosensors. Diary responses were evaluated against photosensor values from the beginning and end of each rest interval (n=194 rest intervals), as well as against sleep measures, utilizing linear mixed models.ResultsResponses to light questions were related to actual light measures at bedtime, controlling for shift type and experimental condition. In addition, subjective light information at bedtime and waking was related to both objective and subjective sleep parameters, with data generally indicating poorer sleep with light in the sleeping environment.ConclusionQuestions addressing perception of light in the sleeping environment may provide a crude yet affordable metric of relative photic intensity. Further, as responses relate to sleep outcomes, subjective light information may yield valuable insights regarding mechanisms and outcomes of clinical significance in sleep and circadian research.

Indium-doped zinc oxide (ZnO) thin films were coated onto glass and silicon substrates at different indium concentrations (0%, 2.5%, 5%, and 7%) using successive ionic layer adsorption and reaction (SILAR) method. Furthermore, crystalline structural, morphological, and elemental properties of indium-doped ZnO thin films were characterized using X-ray diffraction (XRD), scanning electron microscopy (SEM), and EDAX techniques. Moreover, the optical properties were analyzed using UV–vis optical absorption, photoluminescence (PL), and Raman spectroscopy techniques. XRD analysis confirmed the growth of ZnO films with perfect inclusion of indium ions into the ZnO lattice of the hexagonal wurtzite structure. Moreover, the optical studies showed improved transmittance and band gap with the indium doping of up to 2.5%. The photosensor fabricated using the ZnO film doped with 2.5% indium concentration exhibited maximum response regarding sensing properties. A p–n heterojunction device fabricated by coating the 2.5% indium-doped ZnO on p-Si substrate showed good rectifying property with photovoltaic nature, and it responded well for UV region.

The microwave-assisted successive ionic layer adsorption and reaction (mSILAR) deposition method was employed for the synthesis of nano-polycrystalline zinc oxide (ZnO) thin film. In this study, annealing of the prepared ZnO samples was carried out in an air and argon atmosphere. The morphology, crystallinity, and phase of the deposited nanostructured ZnO films were established with a field-emission scanning electron microscope (FESEM) and x-ray diffraction (XRD), respectively. The elemental compositions and chemical states of the ZnO nanostructures were determined by x-ray photoelectron spectroscopy (XPS), and the surface properties were evaluated using Brunauer–Emmett–Teller (BET) surface area analysis. The semiconducting behavior of the film was examined by plotting the current–voltage (I–V) characteristics. Moreover, temperature-dependent electrical resistance, photoconductivity, and photocatalytic studies were also carried out. This study showed that by electron beam irradiation, the electrical and photocatalytic activity, and the photo-conducting properties of ZnO thin film can be improved to the desired level. [ABSTRACT FROM AUTHOR]

Copyright of Electronic Processing of Materials / Elektronnaya Obrabotka Materialov is the property of Institute of Applied Physics and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

BLUF (blue light sensor using flavin) proteins are the blue light receptors that consist of flavin-binding BLUF domains and functional domains. Upon blue light excitation, the hydrogen bond network around the flavin chromophore changes, and the absorption spectrum in the visible region shifts to red. Light signal received in the BLUF domain is intramolecularly or intermolecularly transmitted to the functional region. In this review, the reactions of three BLUF proteins with similar EAL functional groups within the protein (BlrP1, and YcgF), or with a separated target protein (PapB) are described using time-resolved diffusion technique. The diffusion coefficients (D) of the BLUF domains did not significantly change upon photoexcitation, whereas those of the full-length proteins BlrP1 and YcgF and the PapB–PapA system significantly decreased. The changes in D should be due to diffusion-sensitive conformational changes (DSCC) that alter the friction of diffusion. The time constants of the major D changes of BlrP1 and PapB–PapA were similar (~ 20 ms), although the magnitude of the friction change depended on the proteins. Similarities and differences among the reactions of these proteins were clarified from the viewpoint of DSCC. [ABSTRACT FROM AUTHOR]

Cyanobacteriochromes (CBCRs) are phytochrome-related photosensory proteins that play an essential role in regulating phototaxis, chromatic acclimation, and cell aggregation in cyanobacteria. Here, we apply solid-state NMR spectroscopy to the red/green GAF2 domain of the CBCR AnPixJ assembled in vitro with a uniformly 13C- and 15N-labeled bilin chromophore, tracking changes in electronic structure, geometry, and structural heterogeneity of the chromophore as well as intimate contacts between the chromophore and protein residues in the photocycle. Our data confirm that the bilin ring D is strongly twisted with respect to the B–C plane in both dark and photoproduct states. We also identify a greater structural heterogeneity of the bilin chromophore in the photoproduct than in the dark state. In addition, the binding pocket is more hydrated in the photoproduct. Observation of interfacial 1H contacts of the photoproduct chromophore, together with quantum mechanics/molecular mechanics (QM/MM)-based structural models for this photoproduct, clearly suggests the presence of a biprotonated (cationic) imidazolium side-chain for a conserved histidine residue (322) at a distance of ~2.7 Å, generalizing the recent theoretical findings that explicitly link the structural heterogeneity of the dark-state chromophore to the protonation of this specific residue. Moreover, we examine pH effects on this in vitro assembled holoprotein, showing a substantially altered electronic structure and protonation of the photoproduct chromophore even with a small pH drop from 7.8 to 7.2. Our studies provide further information regarding the light- and pH-induced changes of the chromophore and the rearrangements of the hydrogen-bonding and electrostatic interaction network around it. Possible correlations between structural heterogeneity of the chromophore, protonation of the histidine residue nearby, and hydration of the pocket in both photostates are discussed. [ABSTRACT FROM AUTHOR]

The need for photosensors and gas sensors arises from their pivotal roles in various technological applications, ensuring enhanced efficiency, safety, and functionality in diverse fields. In this paper, interlinked PbS/Sb 2 O 5 thin film has been synthesized by a magnetron sputtering method. We control the temperature to form the nanocomposite by using their different nucleation temperature during the sulfonation process. A nanostructured PbS/Sb 2 O 5 with cross-linked morphology was synthesized by using this fast and efficient method. This method has also been used to grow a uniform thin film of nanocomposite. The photo-sensing and gas-sensing properties related to the PbS/Sb 2 O 5 compared with those of other nanomaterials have also been investigated. The experimental and theoretical calculations reveal that the PbS/Sb 2 O 5 exhibits extraordinarily superior photo-sensing and gas-sensing properties in terms of providing a pathway for electron transport to the electrode. The attractive highly sensitive photo and gas sensing properties of PbS/Sb 2 O 5 make them applicable for many different kinds of applications. The responsivity and detectivity of PbS/Sb 2 O 5 are 0.28 S/mWcm -2 and 1.68 × 10 11 Jones respectively. The sensor response towards NO 2 gas was found to be 0.98 at 10 ppb with an limit of detection (LOD) of 0.083 ppb. The PbS/Sb 2 O 5 exhibits high selectivity towards the NO 2 gas. Density functional theory (DFT) and time-dependent density functional theory (TD-DFT) were used to analyze the geometries, electronic structure, and electronic absorption spectra of a light sensor fabricated by PbS/Sb 2 O 5 . The results are very analogous to the experimental results. Both photosensors and gas sensors are indispensable tools that contribute significantly to the evolution of technology and the improvement of various aspects of modern life., (Creative Commons Attribution license.)

Summary: This report presents the synthesis of MnO2/Co3O4 with N and S co‐doped graphene oxide (GO) hybrid composite by hydrothermal route for supercapacitor and photosensor applications. MnO2/Co3O4 nanoflakes and nanoparticles were directly grown on dual N and S doped GO sheets, where doping was achieved using a single reagent thiourea in one‐pot synthesis. Individual Co3O4 and MnO2 electrodes have poor reversibility and cycling properties due to electrolytic instability and low electrical conductivities. However, the hybrid provides good catalytic properties, and combined with highly conducting two‐dimensional GO it can reduce mismatching properties due to high conductivity and layered structure. The incorporated composite sheet‐like structure provides good mechanical strength with high conductivity, permitting easy ion penetration into the electrode, and providing considerably more active surfaces. Thus, the proposed hybrid material delivers significantly improved performance for supercapacitor and/or photosensor applications, achieving 614 F.g−1 specific capacitance at 1 Ag−1, and exceeding 95% retention up to 10 000 cycles. This composite material also shows good photosensing with 1 order of increased current under visible light. [ABSTRACT FROM AUTHOR]

Resonant tunneling diode photodetectors appear to be promising architectures with a simple design for mid-infrared sensing operations at room temperature. We fabricated resonant tunneling devices with GaInAsSb absorbers that allow operation in the 2 – 4 μm range with significant electrical responsivity of 0.97 A/W at 2004 nm to optical readout. This paper characterizes the photosensor response contrasting different operational regimes and offering a comprehensive theoretical analysis of the main physical ingredients that rule the sensor functionalities and affect its performance. We demonstrate how the drift, accumulation, and escape efficiencies of photogenerated carriers influence the electrostatic modulation of the sensor's electrical response and how they allow controlling the device's sensing abilities. [ABSTRACT FROM AUTHOR]

A thin Si layer transfer process for monolithic 3D (M3D) integration is proposed using hydrogen ion (H+) implantation. The upper Si layer was transferred to CMOS circuits fabricated on the lower substrate by H+ implantation, oxide-to-oxide bonding, and a cleavage process at low temperature (< 500 °C). The M3D system comprising the photosensor connected to the CMOS device was demonstrated, where the thickness and roughness of the transferred Si layer were determined by H+ implantation and subsequent processes. The hetero-junctional photosensor was fabricated on the transferred Si layer, which generated the photocurrent ($\text{I}_{\text {ph}}$) by light exposure. The photosensor and ring oscillator circuits of the vertical structure implemented by the M3D process generated the $\text{I}_{\text {ph}}$ according to the light exposure intensity and showed different frequency behaviors accordingly. Compared with the continuous device scaling approach, M3D may be an alternative scheme for low-power, high-performance, and multi-functional devices. [ABSTRACT FROM AUTHOR]

Indium-doped zinc oxide (ZnO) thin films were coated onto glass and silicon substrates at different indium concentrations (0%, 2.5%, 5%, and 7%) using successive ionic layer adsorption and reaction (SILAR) method. Furthermore, crystalline structural, morphological, and elemental properties of indium-doped ZnO thin films were characterized using X-ray diffraction (XRD), scanning electron microscopy (SEM), and EDAX techniques. Moreover, the optical properties were analyzed using UV–vis optical absorption, photoluminescence (PL), and Raman spectroscopy techniques. XRD analysis confirmed the growth of ZnO films with perfect inclusion of indium ions into the ZnO lattice of the hexagonal wurtzite structure. Moreover, the optical studies showed improved transmittance and band gap with the indium doping of up to 2.5%. The photosensor fabricated using the ZnO film doped with 2.5% indium concentration exhibited maximum response regarding sensing properties. A p–n heterojunction device fabricated by coating the 2.5% indium-doped ZnO on p-Si substrate showed good rectifying property with photovoltaic nature, and it responded well for UV region. [ABSTRACT FROM AUTHOR]

Recent studies have indicated that that the application of nickel oxide (NiO) regulator nano-films is growing. The sol-gel method has become the primary method for preparing NiO thin films. This paper describes a method to achieve optimum NiO thin films through this method. Nanostructured NiO nanoparticle (NP) films were successfully fabricated using the sol-gel method at different annealing temperatures as a photosensor device. This was carried out using a systematic change of parameters, such as the thermal annealing, to study the effect on the size of the metal oxide nanoparticles. The optical, structural and electrical properties of NiO nanoparticle films were characterised by ultraviolet-visible (UV-visible) and X-ray diffraction analyses. The results show that the films exhibit an average grain size depending on the annealing temperature. The optical properties revealed that the deposited films were p-type, and increasing the annealing temperatures leads to a shift in the maximum value of the absorption peak towards long wavelengths (red). This results in a drop in the energy gap as the annealing temperature increases. The voltage-current characteristics for both types of NiO/p-Si heterojunction (dark and illuminated) were investigated as a function of the annealing temperature. This study demonstrated that the best-estimated structural, optical, and electrical characterisations were achieved with NiO films at 650 °C. [ABSTRACT FROM AUTHOR]

One of the features of the development of modern society is the growing need to restrict access to various objects. The main task of the State Border Guard is to ensure the inviolability of the state border, including the prevention of illegal crossing of the state border. Nowadays, presence detection systems are often used for this purpose - devices or functions of a security television system that generate an alarm when movement is detected in the field of view of the camcorder. The aim of the current study is to analyze the efficiency of the use of presence detection systems used in the structural units of the State Border Guard. [ABSTRACT FROM AUTHOR]

[Display omitted] • Dual phototrophs utilize light across the whole visible and NIR spectrum of sunlight. • Their regulation requires precise photoadaptation according to their environment. • On average, dual phototrophs have larger sets of photosensors than heterotrophs. For microbes and their hosts, sensing of external cues is essential for their survival. For example, in the case of plant associated microbes, the light absorbing pigment composition of the plant as well as the ambient light conditions determine the well-being of the microbe. In addition to light sensing, some microbes can utilize xanthorhodopsin based proton pumps and bacterial photosynthetic complexes that work in parallel for energy production. They are called dual phototrophic systems. Light sensing requirements in these type of systems are obviously demanding. In nature, the photosensing machinery follows mainly the same composition in all organisms. However, the specific role of each photosensor in specific light conditions is elusive. In this study, we provide an overall picture of photosensors present in dual phototrophic systems. We compare the genomes of the photosensor proteins from dual phototrophs to those from similar microbes with "single" phototrophicity or microbes without phototrophicity. We find that the dual phototrophic bacteria obtain a larger variety of photosensors than their light inactive counterparts. Their rich domain composition and functional repertoire remains similar across all microbial photosensors. Our study calls further investigations of this particular group of bacteria. This includes protein specific biophysical characterization in vitro , microbiological studies, as well as clarification of the ecological meaning of their host microbial interactions. [ABSTRACT FROM AUTHOR]

[Display omitted] • Development of Bi:ZnO nanopowders was done and reported with improved opto-electrical properties. • Crystallite and grain size were reduced and enhanced the surface-to-volume ratio due to Bi doping. • The 1–5% Bi-doped ZnO showed optical band gap values 3.292, 3.296 and 3.297 eV respectively. • Significant R (0.163 AW−1,) and D* (1.26 × 1010 J) values of 3% of Bi-doped ZnO were observed. • External quantum efficiency (EQE) of the 3 % of Bi-doped ZnO was found 53%. Bi (0, 1, 3 and 5 wt%) doped ZnO nanopowders were generated in this study using a simple and inexpensive wet chemical method. X-ray diffraction, Fourier-transform infrared spectroscopy, Scanning electron microscopy, photoluminescence spectroscopy, UV–Vis-DRS, studies are used to evaluate the effect of dopants in ZnO sample. Crystallite size and grain size of the samples were reduced and enhanced the surface to volume ratio due to Bi doping. Oxygen vacancies and shrinkage of bandgap plays a significant role in enhancement of photosensing property. Bi doped ZnO nanopowders had better photosensing activity than pristine ZnO nanopowders. Also, the doped metal ions improved the photosensing efficiency by increasing electromagnetic wave absorption and inhibiting the recombination rates of charge carriers resulting raise of hole-electron pair production. The significant photosensing parameters responsivity (R), detectivity (D*) and external quantum efficiency (EQE) of the 3 % of Bi doped ZnO sample exhibited maximum values such as 0.163 AW−1, 1.26 × 1010 Jones and 53% respectively. The findings of this present study show that the3 % Bi doped ZnO can be an excellent photosensing material. [ABSTRACT FROM AUTHOR]

This paper describes an experimental study and a quasi-one-dimensional calculation of acceleration of dispersed particles by gas detonation products in an expanding channel. The calculations show the possibility of a significant increase in the velocity of powder particles due to the conical expansion of a detonation channel. For particles with sizes of 30–40 m at cone angles of 2–4°, the maximum velocity increase reaches 35–60%. A method is developed for fixing the radiation of a packet of dispersed particles accelerated in a detonation channel by a photosensor, which makes it possible to measure the particle velocity with an accuracy of 5%. The calculation results are in good agreement with the experimental data. [ABSTRACT FROM AUTHOR]

• A hybrid control strategy is proposed and demonstrated to track the sun's path. • Real-time image data were used to avoid the cloud or wind disturbances. • Photosensors were used to enhance the accuracy of the concentrated daylight. • Tracking difficulties were overcome by operating two different feedback mechanisms. • Fiber-optics was used to transport collected daylight (sunlight) to the taget zone. This paper deals with a computer vision and photosensor based two-axis solar tracking system for an active daylighting system. The real-time image processing was performed by using a Raspberry Pi 4 controller, and processed data were used as an input of an ATmega128 microcontroller to track the sun's path. An active daylighting system requires a higher concentration of sunlight with an acceptable accuracy in different weather conditions. Alone, an image based or photosensor based control strategy cannot fulfill both requirements. Successful integration of two different feedback mechanisms could overcome the tracking difficulties. The system was composed of Raspberry Pi 4 and ATmega128 controllers, a camera, electronic circuits, and stepper motors. The proposed control system could distinguish the objects (e.g., sun or clouds) in front of the camera, and process the data required to run the solar tracker. The integration of extra photosensors and the camera was able to avoid the cloud disturbance. To investigate the efficacy of the solar tracker, it was integrated with the optical fiber cable to transmit harvested daylight for an indoor illumination. [ABSTRACT FROM AUTHOR]

Transparent visible-light sensors are of critical importance in invisible optoelectronic circuits as the interface between the optical and electrical domains. However, devices designed based on photocarrier generation for light sensing limit the transparency of the device in the visible region, as the optically active layer also passively absorbs light continuously. In this work, we present an all-transparent ITO/HfO2/ITO device with the wide bandgap HfO2 functioning as the resistive switching and the light sensing element. Electrically switching the resistive state of the device to a low-resistance soft-breakdown state is demonstrated to cause the wide-bandgap visible-light blind HfO2 to become photoresponsive. This allows us to optically functionalize the device for an optical response by electrical breakdown in the oxide and can be triggered on-demand. Apart from the on-demand optical response in the device, the inherent resistive switching properties of the HfO2 device allow for integration of memory and optical sensing capabilities, presenting a novel phenomenon for optical sensing in invisible optoelectronics.

Copyright of Journal of College of Education is the property of Republic of Iraq Ministry of Higher Education & Scientific Research (MOHESR) and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Herein, we report the photosensing property of CdS thin films. CdS thin films were coated onto glass substrates via a spray pyrolysis method using different spray pressures. Prepared films were characterized using X-ray diffraction (XRD), scanning electron microscopy (SEM), and optical and photoluminescence spectroscopy. XRD analysis demonstrated the growth of crystalline CdS films with crystallite sizes varying from 26 to 29 nm depending on the pressure. The SEM and EDAX analyses revealed nearly-stoichiometric CdS films with smooth surfaces and slight variation in grain morphology due to pressure changes. Optical measurements showed a direct bandgap varying from 2.37 eV to 2.42 eV due to pressure changes. A photodetector was also fabricated using the grown CdS films; the fabricated photodetector exhibited good performance depending on the spray pressure. A spray pressure of 1.5 GPa resulted in high photoresponsivity and external quantum efficiency. Image 1 [ABSTRACT FROM AUTHOR]

This study proposes a novel photodiode with photosensitive cavity structure, realized by simple KOH isotropic etching and ion implantation technology. The main design concept is using the photosensitive surface of the cavity to capture the light rays of the sensing area, so as to further increase sensing performance. A TracePro simulation shows that the light capture effect of a single cavity structure is enhanced as the etch depth increases due to increase in surface sensing area. However, since the etch depth is limited by the wafer thickness, this research proposes to increase the surface area of the photodiode by using an array of micro-cavity units to improve the sensing efficiency while reducing the needed etch depth. The experimental results show that under the same light-receiving conditions, the sensitivity of the photodiode with a single cavity and a multi-cavity is higher than that of the general planar design, by about 20% and 16%. In addition, at a luminance of 0 nt to $80\times 10^{3}$ nt, the linear adaptation rate ($\text{R}^{2}$) of the linear fitted curve is larger than 0.99. [ABSTRACT FROM AUTHOR]

The boosted photosensing performances have been reported for Indium (In) nanoparticles (NPs) capped TiO2 nanowire (NW) array using Glancing angle deposition (GLAD) technique. The In NP based photosensor possessed high ideality factor of ~12.8 and the enhancement in photoresponsivity has been also observed. The ON/OFF switching irradiation for the In NPs based photosensor has increased from $4.6~\mu \text{A}$ to $6.2~\mu \text{A}$ and vice versa with a rise time of 0.45 sec and fall time of 0.56 sec. [ABSTRACT FROM AUTHOR]

This study is about an improved high-quality light-emitting diode (LED) converter for a T8 LED tube. The converter is separated into the AC driving circuit and DC driving circuit. Also, the LED tube was applied with an output ripple eliminator for the optical performance. The AC driving circuit and DC driving circuit are assembled at the end of the LED tube in a G13 base and a G13 base dummy, respectively, and the output ripple eliminator is located on an LED PCB. The proposed LED converter is founded on a SSBB (single-stage buck-boost) converter topology and was designed for 10 W operation for a 600 mm T8 LED tube. The light waveform of the LED tube was measured by a photosensor. The waveform had almost no ripple and was the same as a straight line. The average calculated percent flicker of the proposed LED converter was an average of 1.9% at 100 and 240 VAC, 50 and 60 Hz. The proposed converter has lower power efficiency than a conventional converter by 2.7% at 100–240 VAC, but it still has high power efficiency (>87%). The measurement results represent that the LED output current regulation is below 0.92% at 100–240 VAC and the converter obtains the power factor more than 0.84 and the total harmonic distortion is less than 14.3%. All of the current harmonics reach the IEC 61000-3-2 Class D standards for high-quality LED converters. [ABSTRACT FROM AUTHOR]

A study was conducted to investigate the structural and optical properties of nanocrystalline beta metal-free phthalocyanine (β-H 2 Pc) thin films using computational and experimental methods. DFT calculations using the B3LYP basis set 6–311G were performed to predict the HOMO-LUMO gap of the β-H 2 Pc (2.13 eV). The crystalline structural properties of the β-H 2 Pc were examined through XRD analysis, which revealed that the powder β-H 2 Pc had a monoclinic polycrystalline structure, while the β-H 2 Pc thin film was amorphous. Various methods were used to determine and compare the average crystallite size and microstrain, with the size-strain plot method yielding an average crystallite size and microstrain size of 73.15 nm and 0.0051, respectively. Using SEM to analyze the film's surface topography, the mean grain size was found to be 0.85 µm due to agglomeration. Linear and nonlinear spectrophotometric measurements were employed to examine the optical properties of the β-H 2 Pc thin film. The film exhibited indirectly permitted inter-band transitions, with the onset and fundamental band gaps of 1.51 eV and 2.74 eV, respectively. Furthermore, several absorption and dispersion characteristics for thin films were identified. The properties exhibited by Au/β-H 2 Pc/p-Si/Al heterojunction indicate its potential suitability for photosensor applications. [Display omitted] [ABSTRACT FROM AUTHOR]

Resonant tunneling diode photodetectors appear to be promising architectures with a simple design for mid-infrared sensing operations at room temperature. We fabricated resonant tunneling devices with GaInAsSb absorbers that allow operation in the 2–4 μm range with significant electrical responsivity of 0.97 A/W at 2004 nm to optical readout. This paper characterizes the photosensor response contrasting different operational regimes and offering a comprehensive theoretical analysis of the main physical ingredients that rule the sensor functionalities and affect its performance. We demonstrate how the drift, accumulation, and escape efficiencies of photogenerated carriers influence the electrostatic modulation of the sensor’s electrical response and how they allow controlling the device’s sensing abilities.

This paper reports the fabrication of a CuO/CdS heterostructure and the characterization of its properties for optical sensing. Cadmium sulfide (CdS) and cupric oxide (CuO) films were deposited by spray pyrolysis and hydrothermal techniques in order to fabricate CuO/CdS heterojunction devices. The structural, morphological, and optical properties of the CuO and CdS thin films were analyzed using X-ray diffraction (XRD), field emission scanning electron microscopy (FE-SEM), and UV–vis spectroscopy. The concentration of the sulfur precursor, thiourea, was varied over a range from 0.01 to 0.06 M in the spray coating solution for CdS films, and 0.05 M was found to yield improved structural and optical properties. The prepared p-CuO/n-CdS heterojunction exhibited good optical sensing properties with excellent response and recovery speeds. A possible photosensing mechanism for the fabricated heterostructure is detailed using energy band diagrams. In addition, heterojunction properties, including the ideality factor and conduction mechanism are reported: a fabricated heterostructure diode showed a threshold voltage of 0.036 V and an ideality factor of 1.86. Highlights: p-CuO/n-CdS heterojunction photodiode is fabricated using hydrothermal and spray pyrolysis methods. Sulphur concentration of 0.05 M shows excellent structural and optical properties of CdS film. Fabricated heterojunction ideality factor is 1.86 and I-V nature indicated formation of diode. The photodiode showed fast recovery and response times for visible light sensing. [ABSTRACT FROM AUTHOR]

The passivation layers of an in situ-synthesized cadmium sulfide (CdS) nanowire (NW) photosensor were prepared for two reasons: (1) to improve the physical stability of the NW on an interdigitated electrode and (2) to enhance the immobilization efficiency of proteins for the on-chip immunoassay. The passivation layer was estimated to have suitable optical properties, and the photoresponse of photosensor was increased after the formation of passivation layer. The immobilization efficiency of a parylene-H film through covalent bonding was compared with the immobilization of Z-domains through physical adsorption. Finally, on-chip chemiluminescent immunoassay of bacteria was carried out by immobilizing antibodies against Escherichia coli through Z-domains for the orientation control of antibodies. The limit of detection was determined to be less than 104E. coli/mL (n=3), and the sensitivity of bacterial detection was estimated to be 0.339 pA/E. coli/mL (n=3) with a linearity factor (R2) of 0.999. These results showed that the on-chip chemiluminescent immunoassay for bacterial detection could be performed using passivation layer coated CdS NW photosensor. [ABSTRACT FROM AUTHOR]

A new form of interaction with digital displays is described, using the pages and binding of a physical book as the interface. This leads to a form of augmented book, or a‐book, which can seamlessly trigger multimedia content on a nearby device using embedded light, pressure or touch sensors. [ABSTRACT FROM AUTHOR]

A defect-passivated photosensor based on cesium lead bromide (CsPbBr 3 ) perovskite quantum dots (QD) was fabricated using parylene films, and the photosensor was applied for the microbial detection. The CsPbBr 3 perovskite QDs were synthesized to be homogeneous in size under thermodynamic control, and the perovskite QD-based photosensor was fabricated using MoS 2 flakes as the electron transfer layer. In this work, a parylene film with functional groups was deposited on a photosensor for physical protection (waterproof) and defect (halide vacancy) passivation of the perovskite QD. As the first effect of the parylene film, the physical protection of the perovskite QD from water was estimated by comparing the photosensor performance after incubation in water. As the second effect of the parylene, the interaction between the functional groups of the parylene film and the halide vacancies of the perovskite QDs was investigated through the bandgap, crystal structure, and trap-state density analysis. Additionally, density functional theory analysis on Mulliken charges, lattice parameters, and Gibbs free energy demonstrated the effect of the defect passivation by parylene films. Finally, the parylene-passivated QD-based photosensor was applied to the detection of two kinds of food-poisoning and gastroduodenal disease bacteria ( Listeria monocytogenes and Helicobacter pylori ).

Water-dispersible ZnS:Mn nanoparticles (NPs) were prepared by capping their surface with simple structured amino acids: l-alanine (Ala), l-glycine (Gly), and l-valine (Val) molecules, which have very similar structures except for the terminal organic functional groups. The detailed characterization works for the prepared colloidal NPs were performed using various spectroscopic methods. In particular, the NPs commonly showed UV/visible absorption peaks around 325 nm and PL emission peaks around 590 nm, corresponding to the wavelength of orange color light. In this study, these amino-acid-capped NPs were applied as optical photosensors in the detection of specific divalent transition metal cations in the same conditions. Consequently, all three NPs showed exclusive fluorescence quenching effects upon the addition of Cu (II) metal ions, whereas their quenching efficiencies were quite different to each other. These experimental results indicated that the Gly-ZnS:Mn NPs (k = 4.09 × 105 M−1) can be the most effective optical photosensor for the detection of Cu2+ ions in water among the three NPs in the same conditions. This study showed that the steric effect of the capping ligand can be one of the key factors affecting the sensor activities of the ZnS:Mn NPs.

We report on a room temperature Aerosol Jet printed two-terminal WSe2 crossbar architecture device on flexible substrate that achieves dual functionality of both a resistive random access memory (ReRAM), as well as a photosensor. As a ReRAM, the silver contacted WSe2 device exhibits forming free, sub 1-V switching voltage, and an on-off ratio of 2 orders. Furthermore, the WSe2 ReRAM exhibits both volatile and non-volatile switching behavior with a transition set current of ${2}~\mu \text{A}$ , translating to a low operating power of ${16}~\mu \text{W}$. As a photosensor with the same architecture, the transparent CNT electrodes contacted device allows incident light to pass through for photocurrent generation. The two terminals device allows photo sensitivity to be tuned by bias application. In such mode, a maximum photo responsivity of 1 A/W at a visible light wavelength of 660 nm is exhibited by the device at a bias of 1 V, allowing weak light signals to be amplified. In both cases, the WSe2 device retains its functionality even after bending down to a radius of 5 cm. The fabrication process can be up-scaled and has great potential to be used for conformal electronics system integration. [ABSTRACT FROM AUTHOR]

When purchasing sunglasses it is important to ensure that they offer effective protection against ultraviolet (UV) radiation. Although invisible, this type of radiation can cause serious damage to the retina. The use of lenses without adequate UV protection can prove to be harmful, since the decrease in visible light leads to an increase in the pupil of the eye. In this work, we propose the construction of a device to test the reduction in the light intensity introduced by colored sunglasses lenses. The system is based on color LEDs and a photosensor with integrated amplification. [ABSTRACT FROM AUTHOR]