Red Light-emitting Diodes Research Articles

Portable, smartphone-linked, and miniaturized photonic resonator absorption microscope (PRAM Mini) for point-of-care diagnostics.

We report the design, development, and characterization of a miniaturized version of the photonic resonator absorption microscope (PRAM Mini), whose cost, size, and functionality are compatible with point-of-care (POC) diagnostic assay applications. Compared to previously reported versions of the PRAM instrument, the PRAM Mini components are integrated within an optical framework comprised of an acrylic breadboard and plastic alignment fixtures. The instrument incorporates a Raspberry Pi microprocessor and Bluetooth communication circuit board for wireless control and data connection to a linked smartphone. PRAM takes advantage of enhanced optical absorption of ∼80 nm diameter gold nanoparticles (AuNP) whose localized surface plasmon resonance overlaps with the ∼625 nm resonant reflection wavelength of a photonic crystal (PC) surface. When illuminated with wide-field low-intensity collimated light from a ∼617 nm wavelength red LED, each AuNP linked to the PC surface results in locally reduced reflection intensity, which is visualized by observing dark spots in the PC-reflected image with an inexpensive CMOS image sensor. Each AuNP in the image field of view can be easily counted with digital resolution. We report upon the selection of optical/electronic components, image processing algorithm, and contrast achieved for single AuNP detection. The instrument is operated via a wireless connection to a linked mobile device using a custom-developed software application that runs on an Android smartphone. As a representative POC application, we used the PRAM Mini as the detection instrument for an assay that measures the presence of antibodies against SARS-CoV-2 infection in cat serum samples, where each dark spot in the image represents a complex between one immobilized viral antigen, one antibody molecule, and one AuNP tag. With dimensions of 23 × 21 × 10 cm3, the PRAM Mini offers a compact detection instrument for POC diagnostics.

DEVELOPMENT AND APPLICATION OF A WEARABLE TECHNOLOGY PRODUCT THAT DETECTS AND INFORMS THE PRESENCE OF ELECTRICAL ENERGY

Electrical energy has both positive and negative effects nowadays, with the potential to cause property and human loss. Technical professionals working at electrical energy generation, distribution, and utilization points may die due to carelessness or neglect. Although there are protection elements (fuses, residual current protection relays, etc.) in electrical panels that interrupt the flow of electrical energy in the event of a shock, there may be working areas where energy cannot be cut off due to incorrect electrical connections caused by unauthorized people interacting with the panel. Existing protective components may be insufficient. The experiments include both wired protection elements and wireless detection elements. However, they need to be enhanced because they have limited detection distances. Furthermore, using an ergonomic design can improve operability. New protection and warning features must be designed using developing technology. To prevent employees from being shocked by being exposed to electrical energy in the workplace, AC voltage can be detected without contact using this study, which includes the design and test results of a wearable technology product that warns when electricity is present. An electrical circuit that technical staff can wear on their finger detects voltage without contact and displays the existence of energy with a red LED. It was discovered that the test circuit detects 230V AC electrical energy up to 8 cm away and warns with light.

Carbon dots as a distinctive platform fabricated through a sustainable approach for versatile applications

Red-emitting carbon dots (R-CDs) have garnered significant interest owing to its exceptional fluorescence (FL) characteristics. In this study, we present a one-pot solvothermal synthesis for producing biomass-derived R-CDs, utilizing Birch leaves as the primary raw material. The R-CDs display high solubility in ethanol and demonstrate deep-red emission at 625 nm with narrowband characteristics. After conducting a selectivity assessment with different metal ions, it is observed that R-CDs demonstrate exceptional sensitivity and specificity specifically to Fe3+. This demonstrates a linear relationship up to a concentration of 500 μM, with a detection limit of 0.302 μM (S/N=3). In this research, we created photoluminescent and transparent composites made from polyvinyl alcohol (PVA) with embedded fluorescent R-CDs, using the solution casting method for fabrication. The synthesized R-CDs exhibit robust and consistent FL in solution, whereas, the R-CDs@PVA nanocomposites (NCs) films are transparent and exceptionally flexible. The optimized 0.08 wt% R-CDs demonstrated the most effective ultra violet (UV) blockage across the UV-A (76.84 %), UV-B (74.86 %), and UV-C (78.46 %) region. However, PVA alone absorbed < 25 % of the light in all UV regions. The study explored the shape memory and FL characteristics of the R-CDs@PVA NCs changed under varying conditions such as water, temperature and pH. In alkaline conditions, the FL intensity of the R-CDs@PVA NCs increased due to the deprotonation of the R-CDs surface. In addition, R-CDs dispersed within PVA exhibit superior ink-free patterned substrates, proving to be advantageous for non-destructive template relief printing. Furthermore, R-CDs serve as effective anti-oxidants, combating 2,2-Diphenyl-1-picrylhydrazyl (DPPH) scavenging activity and mitigating the oxidative stress (OS) in red blood cells (RBCs) induced by sodium nitrite (NaNO2). They aid in the restoration of essential stress indicators, encompassing lipid peroxidation (LPO), protein carbonyl content (PCC), total thiol (TT), superoxide dismutase (SOD), and catalase (CAT). Furthermore, R-CDs restored the damaged liver, kidney, heart, and pancreas by regulating biochemical parameters. Furthermore, incorporated R-CDs into red light-emitting diodes (R-LEDs) and white light-emitting diodes (W-LEDs), thereby enhancing plant growth efficiency. The results of this study highlight the possible of R-CDs as non-toxic, UV blocking agents suitable for developing edible coatings and packaging. These properties suggest their applicability in the food industry, anti-counterfeiting (AC) measures, and biomedical applications.

Design of LPG Leakage Detection Device using MQ-2 Sensor Equipped with Hazard Warning System

The use of liquefied petroleum gas (LPG) as household fuel in Indonesia has increased because it has greater heating power and equipment efficiency than other fuels. LPG is flammable and can explode if a leakage occurs and is exposed to a fire source. Therefore, explosions can be anticipated by installing a gas leakage detector equipped with a danger warning feature called Tor-G (LPG Detector) based on the NodeMCU ESP8266 microcontroller using an MQ-2 sensor with a buzzer and LED as a danger warning feature. Tor-G can detect when a gas leakage occurs and provides a danger signal in the form of a sound from a buzzer which can be heard several meters away by the homeowner so that an explosion can be anticipated quickly. This research carried out four tests: the sensor accuracy test, the sensor responsiveness test, the distance between the sensor and the leakage source test, and the responsiveness of the buzzer and LED test. The results of the tests show that the sensor only detects the LPG. The sensor readings are accurate since the value of Rs/Ro on the Tor-G is not much different from that of Rs/Ro on the datasheet, thus producing an error value in the 0% -0.08% range. The ideal installation position of the Tor-G is 75 cm from the gas cylinder and the danger warning system from the buzzer and red LED lights up within 18.88 seconds.

Duration, not timing during the photoperiod, of far-red application determines the yield increase in tomato

Supplementary far-red light may increase fruit yield in greenhouse tomato cultivation. Apart from end-of-day applications, research has focussed on the effects of far-red light during the entire photoperiod, while few studies focused on the timing of far-red application. In this study, we assessed the impact of timing and duration of far-red application on fruit yield and quality in a high-wire tomato crop. Two commercial tomato cultivars were grown under 226 μmol m−2 s−1 of red and white supplementary LED lighting. Far-red light (63 μmol m−2 s−1) was additionally supplied during either the first or the second half of the photoperiod. These treatments were compared to a negative control, where no far-red light was supplied, and a positive control, where far-red light was supplied during the whole photoperiod. A yield component analysis was conducted to identify the parameters responsible for changes in fruit yield. We determined that fruit yield, total fruit dry weight and fruit production per unit of supplementary PAR light (400–700 nm) increased linearly with the duration of far-red application. Fruit yield was increased to a similar extent whether far-red was supplemented in the first or in the second half of the photoperiod. While different light treatments included 0, 14, or 28 % far-red in their cumulative supplementary photon flux density, there were no significant differences in their fruit production per unit of supplementary radiation (400–800 nm). Supplementary far-red increased fruit dry weight per unit of cultivation area by 23 % to 25 % as a result of increasing both plant dry weight (10 % to 12 %) and dry weight partitioning to the fruits (10 % to 14 %). The increase in fruit yield was less than the corresponding increase in total fruit dry weight due to a simultaneous increase in fruit dry matter content. Total soluble solids and pH of the fruits were hardly affected by far-red application. We concluded that supplementary far-red increased tomato fruit yield without compromising fruit quality, with this increase being determined by the duration of far-red application, not by its timing during the photoperiod.

Facile preparation of a highly efficient coin cell supercapacitor based on WO3 nanorods

Developing sustainable energy storage devices is challenging for the progress of energy storage applications. Here, nanotechnology represents a strategic route to reduce the amount of used critical materials, while continuing to take advantage of their properties, thanks to the high surface to volume ratio which characterizes nanostructures. WO3 nanostructures represent a promising active material for energy storage applications, thanks to their wide capability of small positive ions (H+ and Li+) intercalation and their high stability in acidic conditions. The coupling between WO3 nanorods and carbon black powder is studied to realize a highly efficient coin cell supercapacitor. The morphology of WO3 nanorods and carbon black is investigated by using a scanning electron microscope, and the energy storage performances were evaluated by performing cycling voltammetry and galvanostatic charge and discharge analysis, thus obtaining promising specific capacitance results (79 and 70 F/g at 5 mV/s and 0.5 A/g respectively). Moreover, the stability of the obtained coin cell was investigated, thus getting good capacity retention over 250 charge-discharge cycles. Energy and power densities were also calculated, obtaining the highest energy density of 39 Wh/kg at a power density of 500 W/kg. The WO3‑carbon black coin cells are used to power a red LED, so demonstrating the viability for practical applications.

Co-exposure effect of different colour of LED lights and increasing temperature on zebrafish larvae (Danio rerio): Immunohistochemical, metabolomics, molecular and behaviour approaches

Although there are studies in the literature on the effects of different coloured light-emitting diodes (LEDs) on different organisms, there is limited information on how these effects change with temperature increase. In this study, the effects of blue, green, red and white LED lights on the early development process of zebrafish (Danio rerio (Hamilton, 1822)) were comprehensively investigated. In addition, to simulate global warming, it was examined how a one-degree temperature increase affects this process. For this purpose, zebrafish embryos, which were placed at 4 hpf (hours post fertilization) in an incubator whose interior was divided into four areas, were kept at three different temperatures (28, 29 and 30 °C) for 120 h. The group kept in a dark environment was chosen as the control. The temperature of the control group was also increased at the same rate as the other groups. The results showed that at the end of the exposure period, temperature and light colour caused an increase in body malformations. Histopathological damage and immunopositive signals of HSP 70 and 8-OHdG biomarkers in larval brains, increase in free oxygen radicals, apoptotic cells and lipid accumulation throughout the body, increase in locomotor activity, decrease in heart rate and blood flow, and significant changes in more than thirty metabolite levels were detected. In addition, it has been determined that many metabolic pathways are affected, especially glutathione, vitamin B6 and pyrimidine metabolism. Moreover, it has been observed that a one-degree temperature increase worsens this negative effect. It was concluded that blue light was the closest light to the control group and was less harmful than other light colours. The study revealed that blue light produced results that were most similar to those seen in the control group.

Unveiling the Versatility of Coumarin-Integrated with Phenanthroline/Thiabendazole-Based EuIII Complexes for Smart LEDs, Vapoluminescence, and Bioimaging Applications.

Narrow band red-emitting phosphors based on organo-Eu(III) complexes prove their energetic features with surprising performance in smart red/white LEDs, sensing, and biological fields. In this report, a series of unique Eu(III) complexes have been synthesized with coumarin integrated with a class of phenanthroline(Phen)/thiabendazole(TBZ) based ancillary ligands and dibenzoyl methane (DBM)/2-theonyl trifluoroacetone (TTA) as an anionic ligand. The computational study reveals that the TBZ/Phen-based neutral ligands are superior energy harvesters to those other reported analogue neutral ligands. All the Eu-complexes demonstrated outstanding red emission due to electric dipole (ED) transition (5D0 → 7F2) in solid, solution, and thin film with high quantum yield (QY). Theoretical analysis (TD-DFT) and experimental findings describe that the energy transfer (ET) from the ligand's triplet level to the Eu(III) ion is completely occurring. The Eu(III) complexes can potentially be used to fabricate intense hybrid white and red LEDs. All of the fabricated red LEDs revealed high luminous efficiency of radiation (LER) values. The fabricated blue LED based hybrid white LEDs displayed remarkable performance with a low correlated color temperature (5634 K), high color rendering index 88%, and CIE values (x = 0.33; y = 0.342) for 3Eu. By interaction with acid-base vapors, Eu-complexes displayed effectively alterable on-off-on luminescence. Further, cellular imaging shows that Eu-complexes can be a potential biomarker for cancer cell lines.

High Current Efficiency Red Perovskite Light-Emitting Diodes Meeting Rec. 2020 Standard.

Cesium lead iodide light-emitting diodes (LEDs) are attractive for displays due to their Rec. 2020 red standard compliance. However, achieving high current efficiencies (CEs), which is important for displays, is challenging because their emission spectrum is near the tail of the photopic luminosity function. Substituting some iodine with bromine can improve CEs by enlarging the bandgap, but defects easily form in iodine-bromine mixed perovskites. Here, we successfully reduced defect formation by adding organic ammonium salts and zwitterions. The organic ammonium salts do not form low-dimensional perovskites under the hydrogen bonding interaction of zwitterions. Instead, they passivate the cesium vacancy by forming new hydrogen bonds after perovskite crystallization. This approach leads to a red perovskite LED with a high CE of 12.8 cd A-1 and a peak external quantum efficiency of 20.3%, meeting the Rec. 2020 standard. It can be extended to large-area devices (2500 mm2) without a significant efficiency loss.

Carbon Quantum Dots with Highly Efficient Bandgap Emission for Electroluminescent Light-Emitting Diodes

Carbon quantum dots (CQDs) feature bright and tunable photoluminescence, solution processability, and low toxicity, showing great potential in optoelectronics. The multicolor fluorescent CQDs were first fabricated as active layers in our lab, and then the high-performance electroluminescent warm white light-emitting diodes (LEDs) were obtained with the synthesized bright red CQDs. More significantly, through designing the triangular structure of the carbon core, fluorescent CQDs first achieved the narrow-bandwidth (∼30 nm) electroluminescent LEDs with appreciable stability, high color purity, and high luminescence performance. These results lay the foundation for the development of next-generation high performance displays based on CQDs. Here, we will report the large-scale synthesis of CQDs with near-unity photoluminescence quantum yield and the synthesis of red (625 nm) phosphorescent carbon quantum dot organic frameworks (CDOFs) with a quantum yield of up to 42.3% and realization of high-efficiency red phosphorescent electroluminescent LEDs. The LEDs based on the CDOFs exhibited a red emission with a maximum luminance of 1818 cd m−2 and an EQE of 5.6%. This work explores the possibility of a new perspective for developing high-performance CQD-based electroluminescent LEDs.References Yuxin Shi, Louzhen Fan, et al., Red Phosphorescent Carbon Quantum Dot Organic Framework-Based Electroluminescent Light-Emitting Diodes Exceeding 5% External Quantum Efficiency, Am. Chem. Soc. 2021, 143, 45, 18941–18951Ting Yuan, Louzhen Fan, et al., Carbon Quantum Dots with Near-Unity Quantum Yield Bandgap Emission for Electroluminescent Light-Emitting Diodes, Angew. Chem. Int. Ed. 2023, e202218568.Fanglong Yuan，Louzhen Fan, et al., Engineering triangular carbon quantum dots with unprecedented narrow bandwidth emission for multicolored LEDs, Nat. Commun., 2018, 9, 2249. Figure 1

Type II photoinitiators with collagen-based cyanine for cell encapsulation under green-red LED

3D bioprinting with cell-laden materials is an emerging technique for fabricating functional tissue constructs. However, current cell-laden bioinks often lack sufficient cytocompatibility with commonly used UV-light sources. In this study, green to red photoinduced hydrogel crosslinking was obtained by introducing synthesized biosafety photoinitiators and used in light-based direct ink writing (DIW) 3D printing for enabling cell encapsulation successfully. The novel type II photointiators contain iodonium (ONI) and synthesized cyanine dyes CZBIN, TDPABIN, Col-SH-CZ, and Col-SH-TD with strong absorption in the range of 400–600 nm. Collagen-based macromolecule dyes Col-SH-CZ and Col-SH-TD showed excellent cytocompatibility. The photochemistry of these photoinitiators revealed an efficient photoinduced electron transfer (PET) process from the singlet excited states of the dyes to iodonium (ONI), facilitating the crosslinking of the biogels. L929 cells were encapsulated in Gel-MA hydrogels containing various photoinitiating systems and exposed to near-ultraviolet, green, or red LED irradiation. DIW-type 3D printing of Gel-MA bioink with L929 cells was also evaluated. The cell viability achieved with green light encapsulation reached 90 %. This novel approach offers promising prospects for bioprinting functional tissues with enhanced cytocompatibility under visible light conditions.

Identification of Blood Sugar Based on Non-invasive Measurements UsingPhotoplethysmography Method Signal Decoding in Diabetics in Tasikmalaya

Non-invasive blood sugar testing tools are now in great demand among the public. This research aims to develop a non-invasive blood sugar examination tool with a Photopletysmograph signal decoding system based on data acquisition from a wearable sensor device on the wrist. The tool used for data acquisition uses Near Infra Red Light-emitting Diode NIR LED 880 nm, 660 nm and 537 nm. This acquisition transfers signals from the body via a photodiode to a PC Personal Computer for processing using Matlab. The method used in this research is to look for the height of the systolic and diastolic amplitude of the Photopletysmograph PPG signal and use the peak-to-peak voltage Vpp to implement Beer Lambert's law. This method was tested on 54 people, randomly aged 26-89 years, with normal blood sugar to high blood sugar. The results show an error of 18.37% from the gold standard. In conclusion, the use of the PPG signal decoding method has proven to be significant in producing blood sugar values. Furthermore, this method was developed for real-time remote measurements via wearable sensor devices.

Supplementary Far-Red Light for Photosynthetic Active Radiation Differentially Influences the Photochemical Efficiency and Biomass Accumulation in Greenhouse-Grown Lettuce.

Adding far-red (FR, 700-800 nm) light to photosynthetic active radiation (400-700 nm) proved to be a possible approach to increasing plant biomass accumulation for lettuce production in indoor vertical farms with artificial lighting as a sole-source lighting. However, how FR light addition influences plant growth, development, and metabolic processes and the optimal value of FR photon flux density for greenhouse-grown lettuce under sunlight are still unclear. This work aims to quantify the value of supplementary FR light with different intensities on lettuce morphological and physiological characteristics in a greenhouse. Lettuce 'Dasusheng' (Lactuca sativa L.) was grown in a greenhouse under seven light treatments, including white plus red LEDs with FR photon flux density at 0, 10, 30, 50, 70, and 90 µmol m-2 s-1 (WR, WR + FR10, WR + FR30, WR + FR50, WR + FR70, and WR + FR90, respectively), and lettuce grown with sunlight only was marked as natural light (NL). FR light addition improved the electron transport flux per cross section and performance index (PIabs, PItotal) and decreased the changes in relative variable fluorescence of lettuce leaves compared to plants under NL. Specifically, the PIabs of lettuce leaves were 41%, 41%, 38%, 33%, 26%, and 25% lower under control than in plants under treatments WR + FR90, WR + FR70, WR + FR50, WR + FR30, WR + FR10, and WR, respectively. Leaf number, leaf area, and biomass accumulation of lettuce followed a quadratic function with increasing FR light intensity and were the highest under treatment WR + FR50. The shoot fresh weight and dry weight of lettuce were increased by 111% and 275%, respectively, under treatment WR + FR50 compared to NL. The contents of vitamin C, reducing sugar, total soluble sugar, and starch in lettuce showed a similar trend with biomass accumulation. In conclusion, with commonly used photosynthetic photon flux density (PPFD, 400-700 nm) around 200 μmol m-2 s-1, supplementary FR light intensity of 30~50 μmol m-2 s-1 was suggested to enhance the photochemistry efficiency, biomass accumulation, and carbohydrates' contents in greenhouse-grown lettuce.

Green Synthesis of Silver Nanoparticles using Moringa oleifera: Implementation to Photoantimicrobial of Candida albicans with LED Light

Green synthesis of silver nanoparticles using Moringa oleifera (AgNPs/MO) was carried out to produce nanoscale antifungal agents which are used as photosensitizing agents in photoantimicrobial therapy. This study focused on investigating the potential of AgNPs/MO producing some toxic radical compounds that inhibit the growth of Candida albicans biofilms. The inhibition mechanism uses the principle of photoinactivation treatment which combines a photosensitizer with an LED light source at a power of 100 mW for 60 - 300 s of exposure. Quantitative data analyzed were the number of viable cells and radical compounds, formed by malondialdehyde (MDA) level. It is investigated through staining the XTT (2,3-Bis-(2-Methoxy-4-Nitro-5-Sulfophenyl)-2H-Tetrazolium-5-Carboxanilide) and TBARS (Thiobarbituric Acid Reactive Substances). The results show that the maximum wavelength of AgNPs is 440 nm while the Moringa oleifera has 2 peaks at 425 and 635 nm. The maximum effect occurred in the group of photosensitizer AgNPs/MO combined LED with percentage inactivation about 76.80 % for blue LEDs and 76.20 % for red LEDs. The group of LED irradiation without photosensitizer obtained about 51.85 % for blue LEDs and 50.04 % for red LEDs. The MDA level group of AgNPs/MO combined LED also produced MDA levels of 1.772 nmol/mL for blue LED and 1.617 nmol/mL for red LED. Meanwhile, the application of photoantimicrobial using only LEDs produced MDA levels of only 1.353 nmol/mL for blue LEDs and 1.347 nmol/mL for red LEDs. This research has shown that the green synthesis of AgNPs/MO has a good potential to inhibit the growth of Candida albicans biofilms as a photosensitizer agent. HIGHLIGHTS Silver nanoparticles (AgNPs) combined with Moringa oleifera (MO) extract have been shown to have potential as a photosensitizer to inhibit the growth of Candida albicans Green synthesis AgNPs/MO have a characteristic spectrum at 440 nm which is close to the blue light spectrum. Green synthesis AgNPs/MO combined with LED light irradiation energy can reduce the cell viability of Candida albicans up to 76.80 % through the XTT assay staining test method and produce 1.772 nmol/mL of Malondialdehyde that reacts with ROS compounds to cause cell damage. GRAPHICAL ABSTRACT

Thermal management towards ultra-bright and stable perovskite nanocrystal-based pure red light-emitting diodes

Despite the promising candidacy of perovskite nanocrystals for light-emitting diodes, their pure red electroluminescence is hindered by low saturated luminance, severe external quantum efficiency roll-off, and inferior operational stability. Here, we report ultra-bright and stable pure red light-emitting diodes by manipulating Joule heat generation in the nanocrystal emissive layer and thermal management within the device. Diphenylphosphoryl azide-mediated regulation of the nanocrystal surface synergistically enhances the optical properties and carrier transport of the emissive layer, enabling reduced Joule heat generation and thus lowering the working temperature. These merits inhibit ion migration of the CsPb(Br/I)3 nanocrystal film, promising excellent spectra stability. Combined with the highly thermal-conductive sapphire substrates and implementation of pulse-driving mode, the pure red light-emitting diodes exhibit an ultra-bright luminance of 390,000 cd m−2, a peak external quantum efficiency of 25%, suppressed efficiency roll-off, an operational half-life of 20 hours, and superior spectral stability within 15 A cm−2.

Enhanced electrochemical performance of nickel cobalt sulfide microspheres for high energy symmetric supercapacitors

Herein, Nickel cobalt sulfide (NCS) microspheres are successfully synthesized by an easy one-step hydrothermal method at different reaction conditions. The as-synthesized samples are used as electrode material to demonstrate their practical application for supercapacitors (SCs). Various techniques including X-ray diffraction (XRD), Fourier transform infrared spectra (FTIR), Scanning electron microscopy (SEM), Energydispersive X-ray (EDX) spectroscopy are used for structural and morphological characterization of the synthesized materials which confirmed the successful formation of NCS. The electrochemical performance of prepared samples is tested using cyclic voltammetry (CV), galvanostatic charge/discharge (GCD) and electrochemical impedance spectroscopy (EIS). The optimized NCSW-200 sample delivered a remarkable specific capacitance of 369 F g−1 at 0.5 A g−1. The energy and power density exhibited by NCSW-200 sample are as high as 32.8 Wh kg−1 and 266.6 W kg−1, respectively. After 2000 consecutive charge/discharge cycles, capacitance retention of 67% is achieved, depicting better cyclic stability. To illustrate the practical feasibility of the prepared symmetric cells of the optimized sample NCSW-200, a lab scale setup of three SC cells connected in series is fabricated and tested using a red light emitting diode (LED). The SC setup is able to illuminate a red LED for 2.5 minutes. The electrochemical performance demonstrated by NCS microspheres suggests its viable application as supercapacitor electrodes.

Synthesis of layered scheelite SrLa2(MoO4)4: Eu3+ red phosphors with high quenching concentration and superior quantum efficiency for improving plant photosynthesis

Plant growth light-emitting diodes (LEDs) are gaining more interest in indoor agriculture because they can provide light spectra that better suit the growth needs of crops. Nevertheless, the big challenge of developing red phosphors that exhibit both exceptional thermal stability and high quantum efficiency remains a daunting undertaking. In this work, Eu3+ activated SrLa2(MoO4)4 red phosphors with layered scheelite structure have been successfully developed. When excited with light of 394 nm, these novel phosphors show the strongest emission at 615 nm. Particularly, the addition of NH4Cl flux significantly increased the quantum efficiency of SrLa2(MoO4)4: Eu3+, reaching an impressive 94.5%. In addition, even at a high temperature of 150 °C, the luminescence intensity remained at a remarkable 65.3% in comparison with the room temperature (RT) emission intensity. A red LED device with a photoelectric conversion efficiency of 5.4% and an output power of 35.9 mW at a drive current of 200 mA was prepared by using this red phosphor. Plant photosynthesis study demonstrated that the lotus leaves exposed to red LED lighting for a few weeks had a larger average diameter than those exposed to natural sunlight, which shows that the SrLa2(MoO4)4: Eu3+ phosphor efficiently converts the light provided by LEDs into red light beneficial for plant growth.

Enhancing the phytoremediation efficiency of Bacopa monnieri (L.) Wettst. using LED lights: a sustainable approach for heavy metal pollution control.

In this study, the impacts of LEDs on the phytoremediation of arsenic (As) and mercury (Hg) by Bacopa monnieri (L.) Wettst. were investigated, along with the examination of the biochemical characteristics of plants exposed to metal-induced toxicity. In vitro multiple and rapid plant propagations were successfully achieved by adding 1.0mg/L 6-Benzyl amino purine (BAP) to the Murashige and Skoog (MS) basal salt and vitamin culture medium. For plant-based remediation experiments, different concentrations of As (0-1.0mg/L) and Hg (0-0.2mg/L) were added to the water environment, and trials were conducted for four different application periods (1-21days). White, red, and blue LEDs, as well as white fluorescent light, were preferred as the light environment. The results revealed that LED lights were more effective for heavy metal accumulation, with red LED light significantly enhancing the plant's phytoremediation capacity compared to other LED applications. Moreover, when examining biochemical stress parameters such as levels of photosynthetic pigments, protein concentrations, and lipid peroxidation, plants under red LED light showed better results. Generally, the lowest results were obtained under white fluorescent light. These findings contribute to phytoremediation studies by highlighting the integration of LED lights, thereby enabling the development of a more effective, cost-efficient, and environmentally sustainable remediation system compared to other treatment methods.

Combining red photobiomodulation therapy with polydioxanone threads for wrinkle reduction in the glabella region: A randomized, controlled, double-blind clinical trial.

The combination of polydioxanone (PDO) threads with other technologies has garnered significant interest for rejuvenation purposes. Photobiomodulation (PBM) has the potential to improve patient comfort and recovery after minimally invasive rejuvenation protocols and also contribute to the overall efficacy of these procedures, fostering an integrative approach to cutaneous rejuvenation. The objective os this work was to investigate concurrent application of PDO threads and red LED PBM on glabellar static wrinkles, in a parallel randomized sham-controlled trial. Forty individuals with Glogau aging classification levels 3 and 4, static glabellar wrinkles, and no significant comorbidities received PDO threads applied along glabellar line. Effective PBM group received 1.35 J and 630 nm red LED light punctually along threads, twice weekly for nine sessions over 30 days. The outcome measures were swelling assessment, dermal thickness and PDO thread degradation via linear ultrasound. No swelling was detected 24 h post-PDO thread application, hindering PBM effect assessment. PDO threads induced dermal thickening; no added effect with PBM. No significant difference in thread hydrolysis between groups, though some ultrasound records inconclusive on thread presence. The absence of swelling may stem from various factors, including the timing of post-procedure swelling assessment, operator proficiency in thread application, and procedural characteristics. No evidence supports the notion that PBM augments dermal thickening, however other light parameters should be studied. Insufficient data to demonstrate PBM's effectiveness in controlling post-procedure swelling. Combination of PBM with PDO thread application doesn't enhance dermal thickening, nor accelerate thread degradation at the parameters used here.

SMART GARBAGE BIN

ABSTRACT: The smart trash can utilizes an ultrasonic sensor (like SONAR) to detect garbage proximity, prompting the servo motor to open the lid when garbage is nearby and closing it otherwise. By this our smart trashcan features sensor-based opening, enabling touchless operation for convenient disposal, ideal for hands-free access when busy or avoiding contact. Additionally, a moisture detector segregates wet and dry waste as per government protocols. An odour detector alerts users to foul smells, prompting timely disposal. A red LED indicates fullness, aiding efficient waste management. This innovative solution enhances public sanitation, suitable for street installation. An accompanying app locates nearby available bins, promoting convenient disposal. Keyword – garbage, smart trash can