Compact Fluorescent Research Articles

Analysis of Losses Associated with Series Resistance (Rs) in Simple-Structured c-Si Solar Cells

The assessment of photovoltaic devices, which convert light energy into electricity, has become significantly more relevant due to the aspiration to reduce pollution on a global scale. In this context, the pursuit of optimizing the efficiency of converting light energy into electrical energy involves exhaustive studies and structural analyses of solar cells, all directed toward achieving this goal. This study introduces a research proposal aimed at analyzing the losses associated with series resistance (Rs). The analysis takes into account each component comprising this resistance, proposing a network of resistances that precisely models each of these elements. The aforementioned research focused on simple-structured crystalline silicon cells. During this investigation, the junction depth (xj) of the n-p materials was varied, with the aim of achieving efficiencies in the range of 12%. However, in the pursuit of this desired efficiency, a significant impact on series resistance was observed when analyzing the I-V curves of the cells obtained in each manufacturing process.

AN ANALYSIS OF DIFFERENCE IN FEMALES AND MALES ATTITUDE TOWARDS ECO-FRIENDLY PRACTICES AT HOME

Background: Eco-friendly behavior, sometimes referred to as green behavior or eco-behavior, is the idea that people, groups, and communities should make decisions and take activities to reduce their environmental effect and advance ecological sustainability. Ecological behavior is essential for maintaining biodiversity, protecting ecosystems, and conserving natural resources. The current study focuses on the environmentally conscious actions that Bhopal city’s men and women take at home. Objective: The objective of the study was to examine the attitude of men and women towards eco friendly habits at home. Methodology: The present research is quantitative, in nature. The study was conducted in the Bhopal city. Convenience sampling was used for the collection of the data. Respondents were asked closed-ended questions on 5-point Likert scale related to their demographic profile and their attitude towards eco friendly practices at home. 270 responses from162 male and 108 were female respondents aged more than 18 years was collected. Descriptive statistics was adopted to get the results of present research. Results: In order of importance male showcased importance for saving water (84%), switch the light off when leaving a room (76.5%), use of energy efficient light bulbs (76.5%) and turn AC off in unoccupied rooms (75.3%) are the top four eco-friendly practices. For female switching the light off when leaving a room (90.7%), saving water (83.3%), turning AC off in unoccupied rooms (81.5%) and turning heat off in unoccupied rooms (79.6%) were the top four eco-friendly practices followed at their homes. Conclusion: Saving water, switching the light off when leaving a room, using of energy efficient light bulbs and turning AC off in unoccupied rooms were the top four eco-friendly practices which are mostly practiced by males at their homes. For female switching the light off when leaving a room, saving water, Turning AC off in unoccupied rooms and Turning heat off in unoccupied rooms were the top four eco-friendly practices.

Influence of the Supply Voltage Variation on the Conducted Emission in the Frequency Range up to 150 kHz Injected into the Power Grid by CFL and LED Lamps—Case Study

In normal operating conditions, the mains voltage level provided by low-voltage distribution networks follows time-varying patterns within permissible limits. The statistical characterisation of disturbances inserted into the power grid by nonlinear electrical devices is useful since operators are able to establish power quality limits and assess the residual capacity of networks for new smart installations, which may include a multitude of power electronic devices. Existing standards related to emission tests recommend using a power supply source in the measurement circuit with a nominal voltage parameter. However, the range of permissible variations of relevant supply voltage parameters may have an impact on conducted emissions. It can also be considered that the symptoms of supply voltage variations may manifest themselves differently depending on the equipment’s architecture and also the range of frequency observation with reference to harmonics and supraharmonics. The purpose of this study is to measure and analyze non-intentional conducted emissions injected into the power grid by lighting devices, methodically, by numbers of studies under different supply voltage conditions within two frequency bands. The emission is evaluated separately in two ranges: up to 2 kHz and 9-150 kHz. Obtained results show that the level of conducted emission introduced into the low voltage network by modern lighting sources like fluorescent and LED lamps varies with the supply voltage level compared to the emission generated in the nominal voltage level condition. Additionally, in the case of a spectrum of higher frequencies, some trends of shifting of the characteristic frequency bands are recorded. The potential of the obtained results is to complement the knowledge of the emission of modern lighting sources, which can be further used for digital models of these devices and to estimate the impact on the grid under real working conditions.

Facile preparation of environmental benign LED white light active humic acid nanolayer coated titanium dioxide photocatalyst for bisphenol A degradation

Natural organic matter is a mixture of microbial decomposition products widely found in surface and groundwater. These organic materials have great potential as carbon-based precursors for chemical synthesis. This work demonstrated the development of a green photocatalyst via a facile adsorption process that combined colloidal titanium dioxide (TiO2) with humic acid. The resulting photocatalyst was visible light active and able to completely degrade 5 mg/L of BPA within 6 h under the irradiation of energy-efficient LED white light. The first-order kinetic rate constant of the reaction was determined to be 1.7 × 10−2 min−1. The enhanced photocatalytic activity was attributed to the decreased band gap energy and effective charge separation that limits the photogenerated electron-hole recombination. The outcome of this research opened an opportunity for the development of sustainable functional materials using natural organic matter.

Satellite Hyperspectral Nighttime Light Observation and Identification with DESIS

The satellite imagery of nighttime lights (NTLs) has been studied to understand human activities, economic development, and more recently, the ecological impact of brighter night skies. The Visible Infrared Imaging Radiometer Suite (VIIRS) Day–Night Band (DNB) offers perhaps the most advanced nighttime imaging capabilities to date, but its large pixel size and single band capture large-scale changes in NTL while missing granular but important details, such as lighting type and brightness. To better understand individual NTL sources in a region, the spectra of nighttime lights captured by the DLR Earth Sensing Imaging Spectrometer (DESIS) were extracted and compared against near-coincident VIIRS DNB imagery. The analysis shows that DESIS’s finer spatial and spectral resolutions can detect individual NTL locations and types beyond what is possible with the DNB. Extracted night light spectra, validated against ground truth measurements, demonstrate DESIS’s ability to accurately detect and identify narrow-band atomic emission lines that characterize the spectra of high-intensity discharge (HID) light sources and the broader spectral features associated with different light-emitting diode (LED) lights. These results suggest the possible application of using hyperspectral data from moderate-resolution sensors to identify lamp construction details, such as illumination source type and light quality in low-light contexts. NTL data from DESIS and other hyperspectral sensors may improve the scientific understanding of light pollution, lighting quality, and energy efficiency by identifying, evaluating, and mapping individual and small groups of light sources.

Enhanced efficiency and thermal performance of multistage gradient doping Ce:YAG transparent ceramics for laser lighting

The key to realizing the applications of ceramic based laser lighting devices depends on the heat management capability of color converters. In order to sufficiently absorb the blue light and smoothen the temperature gradient of luminescent ceramics, multistage gradient doping Ce3+:Y3Al5O12 (Ce:YAG) transparent ceramics (TCs) with five different concentrations were designed, including 0.01 at%, 0.05 at%, 0.1 at%, 0.2 at% and 0.4 at% Ce. The composite green bodies were prepared by aqueous tape casting and multistage gradient doping Ce:YAG TCs, with concentrations from low to high, were fabricated by vacuum sintering. The in-line transmission values at 800 nm of composite structure Ce:YAG TCs could reach 80.3%. Under 21.13 W/mm2 blue laser excitation, the gradient doping Ce:YAG TC (1.32 mm) realized a high luminous efficacy of 280.3 lm/W, which was 15.8% higher than that of 0.15 at% Ce:YAG TC (240.27 lm/W). Finally, during lighting process, the input-output temperature differences (Tin-Tout) between excitation surface and light-exit surface of 0.15 at% Ce:YAG TC was 5 ℃, while that in gradient doping TC reduced by 50% (2.5 ℃). The results indicate that the multistage gradient doping Ce:YAG TCs will be an interesting color converter for high-power and energy-saving laser-driven lighting.

Coping with darkness: residents’ experience of reduced outdoor lighting in neighbourhoods

Despite ongoing replacement of old lighting installations with new energy-efficient light emitting diodes, the energy crisis has led to the implementation of strategies for reducing energy use for public outdoor lighting in neighbourhood environments. This would save money and reduce light pollution; however, the situations should be evaluated from the residents’ perspective. This paper presents a pilot study, which aimed to explore how residents experience and respond to reduced outdoor lighting in their neighbourhoods during dark hours, by applying the adapted Human-Environment Interaction model to understand the relation between outdoor lighting quality, neighbourhood quality and local independent mobility from the residents’ perspective. The pilot study was based on a short questionnaire (N =76, 29 males, 47 females, Mage = 66.66 years) and telephone or online interviews (N = 13, 5 males, 8 females, Mage = 68.08 years) with the residents living in the neighbourhood areas, in Southern Sweden, where strategies were employed for reducing the use of public outdoor lighting. Data were collected between February and March 2023. Overall, the results affirmed the important role of outdoor lighting quality in residents’ experience of neighbourhood environments and local independent mobility (i.e. the ability of residents to walk or move around on their own in their neighbourhood area), whereas the effect of reduced outdoor lighting was rather insignificant. The interviews further showed different experiences of the reduced outdoor lighting and how the residents coped with the lighting conditions by using solutions (i.e. headlamps, flashlights, bike lamps and reflectors), and that high-level perceived safety from crime in the neighbourhoods was found to play an important role in local independent mobility during dark hours. The adapted conceptual model allowed for the evaluation of outdoor lighting conditions considering both internal and external factors from the residents’ perspective, and could provide a basis for discussion about potential changes in public outdoor lighting.

The Physiological Basis of Alfalfa Plant Height Establishment.

Plant height plays an important role in crop yield, product quality, and cultivation management. However, the physiological mechanisms that regulate the establishment of plant height in alfalfa plants remain unclear. Herein, we measured plant height traits, leaf characteristics, photosynthetic physiology, cell wall composition, and endogenous hormone contents of tall- and short-stalked alfalfa materials at different reproductive periods. We analyzed the physiology responsible for differences in plant height. The results demonstrated that the number of internodes in tall- and short-stalked alfalfa materials tended to converge with the advancement of the fertility period. Meanwhile, the average internode length (IL) of tall-stalked materials was significantly higher than that of short-stalked materials at different fertility periods, with internode length identified as the main trait determining the differences in alfalfa plant height. Leaf characteristics, which are closely related to photosynthetic capacity, are crucial energy sources supporting the expression of plant height traits, and we found that an increase in the number of leaves contributed to a proportional increase in plant height. Additionally, a significant positive correlation was observed between plant height and leaf dry weight per plant during the branching and early flowering stages of alfalfa. The leaves of alfalfa affect plant height through photosynthesis, with the budding stage identified as the key period for efficient light energy utilization. Plant height at the budding stage showed a significant positive correlation with soluble sugar (SS) content and a significant negative correlation with intercellular CO2 concentration. Moreover, we found that alfalfa plant height was significantly correlated with the contents of indole-3-acetic acid in stem tips (SIAA), gibberellin A3 in leaves (LGA3), zeatin in stem tips (SZT), and abscisic acid in leaves (LABA). Further investigation revealed that SS, SIAA, and LGA3 contents were important physiological indicators affecting alfalfa plant height. This study provides a theoretical basis for understanding the formation of alfalfa plant height traits and for genetic improvement studies.

Creating a new yellow and blue combination transparent film for Panax ginseng C.A. Meyer growth based on orthogonal designs

Panax ginseng C.A. Meyer originates from old-growth forest environments, where the light intensity and spectrum reaching the forest bed are influenced by the canopy and humidity. In farmlands, suitable light intensity for cultivation is achieved by controlling the light transmission rate using shading nets, while light quality is regulated by a cover of yellow or blue transparent film. Such films have a light quality distinct from that produced by old-growth forests. Herein, a large composite film was developed by alternating small pieces of yellow and blue transparent film. An orthogonal array was used to evaluate the influence of the small transparent film area (STFA), yellow transparent film (YTF) number, and blue transparent film (BTF) number on the associated changes in ginseng in a range of fluorescence-, photosynthesis-, morphology-, and crop quality-related factors. Our results showed that light intensity was influenced primarily by STFA, which caused an overall decrease, while the light quality ratio was affected primarily by YTF number, which increased the proportion of red light and decreased that of blue light, with corresponding influence on different growth parameters. Based on these observations, an improved yellow and blue combination transparent film (YBCTF) with the following characteristics was established: STFA: 15 × 15 cm, YTF: two pieces, and BTF: three pieces. The improved YBCTF facilitated efficient light energy use by the plants, and led to an increase in leaf area, the per leaf photosynthetic rate, dry root weight, and the per root single ginsenoside yield. The findings present a relatively low-cost approach for optimising the light environment of ginseng cultivated in farmland and other crops in large-scale agricultural settings.

Preparation and photoluminescence study of rare-earth-free red emitting La3Ga5SiO14:Mn4+ phosphors

Given the growing interest in eco-friendly lighting solutions, the use of high-quality phosphors has become integral to the advancement of all-solid white light-emitting diodes (WLEDs). One novel phosphor, La3Ga5SiO[Formula: see text]:Mn[Formula: see text] (LGS), has been successfully synthesized via a high-temperature solid-state reaction. The crystal structure of LGS is classified as belonging to the trigonal phase, with a space group P321. The excitation spectrum exhibits a wide peak within the wavelength range of 280–440 nm. It emits a highly intense red light, with a peak emission occurring at 715 nm within the spectral range of 670–740 nm is attributed to the transition of Mn[Formula: see text] from 4A2g to 4T2g. LGS:Mn[Formula: see text] demonstrates a favorable quantum efficiency of 16% when doped with a concentration of 0.25 mol% Mn. The decay curve of LGS:Mn[Formula: see text] exhibits a pattern of decreasing lifetime as the dopant concentration increases. Additionally, the LGS:Mn[Formula: see text] products demonstrate a CIE chromaticity of (0.688, 0.2644), which is located within the deep red light region. All the aforementioned findings support the potential application of LGS:Mn[Formula: see text] specimens in WLEDs, thereby contributing to the progress of environmentally friendly and energy-efficient lighting.

Nuclear mutagenesis and adaptive evolution improved photoautotrophic growth of Euglena gracilis with flue-gas CO2 fixation

To effectively improve biomass growth and flue-gas CO2 fixation of microalgae, acid-tolerant Euglena gracilis was modified with cobalt-60 γ-ray irradiation and polyethylene glycol (PEG) adaptive screening to obtain the mutant strain M800. The biomass dry weight and maximum CO2 fixation rate of M800 were both 1.47 times higher than that of wild strain, which was attributed to a substantial increase in key carbon fixation enzyme RuBisCO activity and photosynthetic pigment content. The high charge separation quantum efficiency in PSII reaction center, efficient light utilization and energy regulation that favors light conversion, were the underlying drivers of efficient photosynthetic carbon fixation in M800. M800 had stronger antioxidant capacity in sufficient high-carbon environment, alleviating lipid peroxidation damage. After adding 1 mM PEG, biomass dry weight of M800 reached 2.31 g/L, which was 79.1 % higher than that of wild strain. Cell proliferation of M800 was promoted, the apoptosis and necrosis rates decreased.

Exploring Sustainable Clothing Display Design under the Concept of Sustainability

This paper examines sustainable clothing display design under the sustainability concept. The fashion industry faces growing pressure to incorporate sustainability into display design due to environmental concerns and consumer expectations. Employing a comprehensive approach, including literature review, case studies, and consumer surveys, this research establishes a theoretical framework by elucidating sustainable development principles and objectives. Through the analysis of successful sustainable display design cases, particularly within clothing manufacturing and supply chains, the study highlights the pivotal role of brands in this process. Extensive surveys and interviews involving consumers of different demographics and shopping behaviors reveal a positive consumer attitude toward sustainable display design, with sustainability being a significant factor in purchasing decisions. The findings suggest that brands and retailers can enhance their reputation and sales effectiveness by adopting eco-friendly materials, energy-efficient lighting, and reusable display elements. Nevertheless, the study identifies challenges, such as the need for education and standardization in sustainable display design implementation. This study emphasizes the importance of sustainability in clothing display design and its potential to positively impact brand reputation and sales. The research provides valuable guidance to brands and retailers and proposes future research directions, including market segmentation, cultural considerations, and the establishment of sustainable development criteria, to further advance sustainability in the fashion industry.

Synergistic effect of net-houses and light sources on the enhancement of off-season flowering waves and production of ‘Da Hong’ red-fleshed pitaya

To meet the increasing demand for year-round production of ‘Da Hong’ red-fleshed pitaya (Hylocereus polyrhizus), which is limited by its natural flowering season in the summer and has been a dominant cultivar in Taiwan, China and East-SouthEast Asia owing to its self-compatibility and excellent fruit quality, extending the off-season cultivation period has become a crucial endeavor. This study aimed to assess the effects of net-houses and light sources on off-season (spring and winter) fruit quality yield of ‘Da Hong’ red-fleshed pitaya in Taiwan. Mature six-year-old plants were cultivated either in net-houses or open fields (OFs), with night-breaking achieved using artificial lighting: either 100 W incandescent bulbs (IBs) or 23 W compact fluorescent energy-saving bulbs (CFBs). The study was conducted during spring and winter in 2017–2018, with flowering rate and fruit production evaluated. Floral bud emergence in the net-house+IB and net-house+CFB groups preceded that in other treatments by at least 2 weeks during spring, with net-house+IB exhibiting the highest frequency of flowering waves (four in spring and three in winter). Across all treatments, night-breaking via artificial lighting in spring markedly increased yield, with IBs and CFBs producing similar outcomes. Quality-wise, OF cultivation surpassed net-house cultivation in spring, whereas net-house cultivation, particularly with IBs, proved more effective during winter. In summary, net-house cultivation offers several advantages for off-season production, including earlier peak flowering in spring, increased flowering cycles in both spring and winter, and higher flowering rates during winter. Overall, these results may help enhance and stabilize off-season ‘Da Hong’ red-fleshed pitaya cultivation. Moreover, the significance of our study has the potential to revolutionize the flowering physiology, the strategy to enhance year-round production and the advancement of agricultural sustainability in pitaya.

Design of a Smart Lighting System Based on Sensor Integration and Automation

As a crucial application of modern technology, smart lighting systems are transforming our interaction with the living environment. The key lies in utilizing advanced sensor technology to maximize lighting efficiency and conserve energy. This paper focuses on designing a sensor-based lighting control system that integrates Passive Infrared and light intensity sensors for the automated management of environmental lighting. Our research has extensively explored the integrated application of PIR and light-intensity sensors. The design aims to automatically adjust indoor lighting based on environmental light conditions and the presence or absence of occupants to enhance comfort and energy efficiency. The sensor fusion algorithm was optimized through a series of experiments to improve detection accuracy and effective energy utilization. Based on the design analysis, the system can significantly enhance energy savings by reducing unnecessary lighting without compromising occupant comfort. The system’s design also considers rooms of varying sizes and layouts, demonstrating good adaptability and versatility. The significance of this research lies in providing innovative solutions for the smart lighting domain. By enhancing the intelligence and responsiveness of lighting systems in home and commercial environments, our design offers a more intuitive and energy-efficient lighting experience. It paves the way for future developments and innovations in lighting systems. This work highlights the immense potential of sensor-based systems in creating interactive and adaptive environments suitable for diverse settings such as homes, corridors, and underground garages.

Audit Dan Peluang Penghematan Energi Listrik CV Tirta Windu Agung 3 Probolinggo

The use of electrical energy in the building and industrial sectors is very important, especially the use and allocation of funds spent is quite large. So it is necessary to use energy as efficiently as possible. So there is a need for an energy audit to determine the level of electrical energy consumption used, where the results will be compared with predetermined standards. This research was carried out at CV Tirta Windu Agung 3 using a PM5100 and lux meter. From initial audit calculations, the IKE value was found to be 13.42 kWh/m2/year. This IKE value is the total of the buildings and ponds. The IKE value still includes very efficient criteria. Based on the results of detailed audit calculations, the value obtained before improvement was 2.23 kWh/m2/year. The IKE value still includes the criteria for being very efficient or meeting standards. After improvements it became 1.65 kWh/m2/year. Energy saving opportunities are available in indoor and outdoor lighting systems by replacing CFL (compact fluorescent lamp) lamps with Philips LED lamps. Based on calculations, the savings in electrical energy costs are IDR 41,736/day, resulting in savings of IDR 15,233,640/year. Based on the Isc/IL calculation above, it can be seen that the Isc/IL value is 165.4. According to the IEEE 519-2014 standard, the ISC IL value in the range >1000 has a permissible THDi value limit of 15%. The nominal voltage used is 0.4 kV, so the permitted THDv is 8%. Based on table 3.9 THDv and THDi under standard conditions.

Integrated Systems of Light Pipes in Buildings: A State-of-the-Art Review

Artificial lighting comprises nearly one-third of the total electrical load of buildings, resulting in significant carbon emissions. Reducing the carbon emissions caused by artificial lighting is one of the ways to achieve low-carbon buildings. To meet the demand for high-efficiency, energy-saving, and comfortable lighting, light pipes are increasingly used in buildings. This paper reviews the research and development of light pipes and integrated technology. Sky conditions as a dynamic factor always affect the performance of light pipes. The combination of light pipes and an artificial lighting system can effectively solve this problem. A light pipe can be integrated with a ventilation stack to achieve the ventilation and cooling or heating of a building. A lighting-heating coupled light guide can improve the energy efficiency and sustainability in buildings, such as where antimony tin oxide nanofluid is introduced to absorb additional heat and then provide domestic hot water. The application of a photocatalyst to light pipes can realize air purification and self-cleaning. The use of light pipes does not consume electricity and can reduce the time spent using artificial lighting, thus allowing for power savings. From a whole life cycle perspective, the use of light pipes can be a balance of cost and benefit. In conclusion, such information could be useful for engineers, researchers, and designers to assess the suitability of applying integrated light pipes in different building types and examine the potential of energy and cost savings.

Comparative Response of Arbuscular Mycorrhizal Fungi versus Endophytic Fungi in Tangor Citrus: Photosynthetic Efficiency and P-Acquisition Traits

Citrus plants are prone to phosphorus (P) deficiency, especially in acidic soil, making them more dependent on root-associated endophytic fungi for growth and development. Beni-Madonna, a hybrid of Citrus nanko × C. amakusa, is a citrus known as “tangor” that is highly popular in China and other parts of the world due to its deep red color and jelly-like flesh. In this study, the inoculation response to two arbuscular mycorrhizal fungi (Diversispora versiformis, Dv; Funneliformis mosseae, Fm) and an endophytic fungus (Serendipita indica, Si) with regard to the growth, leaf gas exchange, light energy efficiency, P levels, acid phosphatase activity, and expression of the purple acid phosphatase (PAP) and phosphate transporter (PT) genes through a potted experiment using Beni-Madonna (tangor) citrus plants grafted on trifoliate orange (Poncirus trifoliata) was studied. Two years following inoculation, the root fungal colonization rates of inoculated plants were significantly increased, accompanied by an increase in plant height and stem diameter, with Si presenting the best effect. Fungal inoculations also significantly increased the leaf chlorophyll index, nitrogen-balance index, photosynthesis rate, stomatal conductance, transpiration rate, photosynthetic efficiency, and quantum yield of PSII, while it reduced photoinhibition and heat dissipation, with Si having the best effect on light energy efficiency. Si significantly increased leaf and root P levels, as well as root CsPAP1‒3, CsPT2, CsPT3, and CsPT7 expression and soil acid phosphatase activity; Fm in mycorrhizal fungi significantly increased leaf and root P levels, as well as root CsPT1 and CsPT7 expression and root/soil acid phosphatase activity. These observations suggested an advantage of Si over the other two AMF in terms of improved plant growth and P acquisition, while Fm displayed prominent effects on increased photosynthetic efficiency.

Energy Performance and Optimization of Commercial Building under Composite Climate using BIM

Abstract: The use of BIM REVIT for Energy Performance and Optimisation of Buildings (EPOBs) has been shown in this research to be a sustainable and energy-efficient response to the problems posed by climate change and growing energy expenses. These buildings are made to produce as much energy as they consume, ensuring that their net energy consumption is zero. The paper explores the evolution of energy performance and optimisation of buildings and the latest emerging technologies that are enabling their development, comprising innovative sensors, lightweight insulation panels, energy-efficient lighting and HVAC systems, building integrated photovoltaic (BIPV) systems, and smart building automation systems. The effectiveness of these strategies is analysed using Autodesk insights and Revit software. In order to ascertain the effectiveness of energy-efficient and renewable energy strategies, the article also compares energy use intensity (EUI) before and after implementation. The proposed building achieved a significant 44.3% reduction in energy consumption after implementing various energy performance and Optimization strategies for commercial building design, resulting in a mean EUI value of -33.1 kWh/sq. m/year. The analysis was conducted using Autodesk Insights and Revit software, utilising the Building Information Modelling (BIM) approach for building design. This paper concludes with a discussion on the future of energy performance and optimisation and how they are an important step towards achieving sustainable and efficient energy use in the building sector, resulting in cost savings and reducing carbon emissions.

Hetero atom-based metal complexes as emitters in organic light-emitting diodes

The new, more energy-efficient lighting systems and high-quality displays for new age digital devices is the demand of the current generation. In this regard, focused and deliberated research has been done on transition metal complexes as effective building blocks for organic light-emitting diodes (OLEDs). The activity of divalent metallic compounds was investigated through spotlighting Co (II), Ni (II), and Cu (II) metal ions with guanidinium naphthoate as blue phosphors in OLEDs. Using spectroscopic and diffraction techniques, the phosphors produced at the optimal temperature were studied both structurally and thermally. Additionally, the target compound's photophysical investigations in a variety of organic solvents with differing polarities were examined, and the findings were presented. Because of their quick photoluminescence response time and high emission quantum efficiency, Ni (II) complexes have drawn specific attention. Ni (II) complexes precisely exhibit thermally activated delayed fluorescence (TADF) and found to be the most promising materials for future lighting technology. We compared the efficiencies of various complexes in this study to provide an overview of the development of OLEDs. To affirm the pertinency of the synthesized compounds as phosphors, studies like photoluminescence, correlated color temperature, color purity, Duv, and the Television Lighting Consistency Index (TLCI) were performed and their photometric properties were also deliberated. Ni (II) shows an magnificent luminescence character and maximum coloring index for light sources and found to be an essential component for OLEDs.

Novel Ultra-High-Performance Concrete (UHPC) Enhanced by Superhydrophobic and Self-Luminescent Features

This study explores the potential of using basalt reinforced UHPC by incorporating simultaneously self-cleaning and self-luminescent features, paving the way for sustainable advancements in civil engineering. New green formulations of UHPC were developed by integrating supplementary cementitious materials and optimizing water to the binder ratio, followed by using basalt fibers to enhance strength and ductility. The fabricated samples with high particle-packing density exhibit sufficient workability and compressive strength up to 136 MPa, and, when incorporating basalt fibers, a notable reduction in brittleness. The inner microstructure of basalt fibers was observed to be smooth, homogeneously distributed, and well adhered to the UHPC matrix. To ensure the desired long-lasting visual appearance of decorative UHPC and reduce future maintenance costs, a time-effective strategy for creating a light-emitting biomimetic surface design was introduced. The samples exhibit high surface roughness, characterized by micro to nano-scale voids, displaying superhydrophobicity with contact angles reaching up to 155.45°. This is accompanied by roll-off angles decreasing to 7.1°, highlighting their self-cleaning features. The self-luminescence feature showcased intense initial light emission, offering a potential energy-efficient nighttime lighting solution.