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Rare earth elements (REEs) are essential for high-tech and low-carbon economies. Achieving global net-zero emissions by 2050 would require a significant increase in mineral input, including 3–7 times more REEs. At present, there are no direct high-grade ores of heavy REs like terbium. Bastnasite, monazite, and xenotime are the primary sources of terbium, while southern Chinese ion-adsorption clays are the richest commercial sources. To address the scarcity of rare earth resources, countries lacking RE deposits should focus on developing innovative and economically viable recycling techniques for the recovery of REs like terbium from different secondary resources. Spent fluorescent lamp phosphor powder represents a potential secondary resource for terbium recovery, although research efforts have been focused mostly on other REEs than Tb as value-added products. Hydrometallurgical processing is widely employed to extract terbium from different resources. The present review systematically summarizes in detail the major recovery/separation techniques used and critically evaluates the potential of terbium recovery from mineral resources and end-of-life fluorescent phosphor wastes. The advantages and limitations of each of these technologies have been provided. The objective is to foster valuable insights for researchers and the development of economical and promising extraction technologies for the recovery of terbium. [ABSTRACT FROM AUTHOR]

Disruptions in power quality have a negative impact on many energy consumers. These include lighting, where interference manifests itself, among others, in the form of light flickering. The article presents phenomena accompanying the operation of modern light sources against the background of exemplary results of studies on the flicker of conventional light sources, such as incandescent or fluorescent lamps. The flickering effect of light generated in modern lamps can occur under stable voltage conditions in the supply network. The main subjects of the conducted research were solid-state light sources—light-emitting diode (LED) lamps, currently available on the lighting market. To assess the effects of these phenomena, it is necessary to use measures other than those traditionally used. The method used allows for the measurement of flicker resulting from both power supply disturbances and the properties of modern light sources. Using the developed measurement system, it is possible to record temporal changes in flicker coefficients resulting from, for example, changing supply voltage conditions. Due to the possibility of flickering light from sources offered by different manufacturers, as shown by research, it is advisable to carry out measurements at the place of use of the lighting. [ABSTRACT FROM AUTHOR]

This paper reports an efficient in vitro rooting and acclimatization method for Pennisetum 'Vertigo®'. For that purpose, the influence of the IAA (indole-3-acetic acid) in MS (Murashige and Skoog) media, and different types of LED light (100% blue, 100% red, a combination of red and blue (70% + 30%), a combination of red, blue with yellow, green, or far-red (35% + 15% + 50%), and white LED) were investigated. A fluorescent lamp and a medium without auxin were used as controls. Subsequently, the plants were transferred ex vitro in trays to the greenhouse and later transplanted into pots. In all tested combinations, the shoots rooted at a high rate of 70–100% (except under blue light). The best results were obtained under white LED or the fluorescent lamp, where the highest number of roots was formed; however, IAA did not increase the rooting rate, the number, or the weight of roots. Shoots rooted under LEDs and on media containing IAA generally exhibited higher soluble sugar content compared to those rooted on auxin-free media. Consistent with the rooting results, the best acclimatization was observed in plants rooted under white LED or fluorescent light on auxin-free media. [ABSTRACT FROM AUTHOR]

The Sideritis genus includes over 150 species primarily found in the Mediterranean basin, including the S. clandestina subsp. pelopponesiaca from the Peloponnese and S. scardica from North and Central Greece. In vitro seed germination has proven effective for conserving and amplifying the genetic diversity of endangered species such as Sideritis. This study aimed to optimize in vitro germination and seedling growth of S. scardica and S. clandestina subsp. pelopponesiaca under different lighting conditions at 22 °C, including white fluorescent lamps (WFL-BG-40) and LEDs (LED-BGYOR-40, LED-BR-40, LED-BR-80, LED-BR-120) all under a 16-h light/8-h dark photoperiod (WFL: white fluorescent light, B:blue, G:green, Y:yellow, O:orange, R:red, 40–80–120 μmol m−2 s−1), along with a 24-h dark treatment. The results indicated that LED-BR-80 combined with 250 mg L−1 GA3 in the MS medium promoted best germination (40%, day 55) and shoot proliferation in S. clandestina subsp. pelopponesiaca. Conversely, 5-year-old cold stratified S. scardica seeds showed higher germination rates (80%) and robust seedling growth under LED-BGYOR-40 with 250 mg L−1 GA3, particularly thriving in LED-BR-120 for increased shoot height and root number. This is the first report of the efficacy of LED technology in optimizing in vitro conditions for Sideritis species, crucial for their conservation and sustainable commercial cultivation. [ABSTRACT FROM AUTHOR]

Artificial light sources in plant factories offer numerous advantages over traditional plant production. Optimal artificial l ighting systems will provide sufficient light to promote plant growth. Thus, this study aimed to determine different artificial light sources on plant growth, especially on internode length, root length, potassium (K), Calcium (Ca), and magnesium (Mg) contents of green oak lettuce (Lactuca sativa L.). Three artificial light sources were utilized in the plant factory: a fluorescent lamp (FL) typically used in plant factories and two light-emitting diodes (LED): bulb-LED and bar-LED lamps. Alternate periods of 12 h of light and dark were applied to the used factories. The results indicated that the lettuce grown under bulb-LED irradiation exhibited the lowest internode length and highest root length of green oak lettuce, regardless to light intensity and the higher photos ynthetic photon flux density (PPFD) values of bulb-LED at the growing stage. K, Ca, and Mg contents in the lettuce shoot decreased in the order of K > Ca > Mg for all artificial light sources. The highest K, Ca, and Mg contents were 14.77±3.08, 4.77±0.92 and 108.14±9.36 mg/g dried weight (DW) obtained in lettuce grown under FL irradiation. Lower FL light intensity promotes nutrient deficiency, resulting in increased plant uptake. There was no significant difference in nutrient content betwe en plants grown with bulb-LED and bar-LED. The K/Ca and K/Mg mole ratios were lowest in plants grown under FL irradiation. These findings suggest that FL can be used to control lettuce nutrient levels, whereas bulb-LED can be used to control lettuce growth. [ABSTRACT FROM AUTHOR]

Background Understanding the chemical composition of fluorescent lamp residue, particularly potentially toxic elements, is crucial for reducing environmental impacts and human health risks after disposal. However, the challenge lies in effectively analyzing these heterogeneous solid samples. Techniques involving quantitative dissolution become imperative, playing a fundamental role in quantifying trace elements. Objective The aim of this work is to develop and present a new, faster, and more efficient and environmentally friendly method using ultrasound-assisted acid extraction to quantify potentially toxic elements (Cu, Mn, Ni, Sr, and Zn) present in fluorescent lamp waste using the inductively coupled plasma-optical emission spectrometry technique. Methods An ultrasound-assisted acid extraction method for the quantification of potentially toxic elements in fluorescent lamp waste was developed and applied as a greener alternative to conventional digestion methods. For variable optimization, a full factorial design with two levels and two variables (time and temperature) was used to determine which factors significantly affected the observed response. Results The results obtained for the developed extraction method were compared with a reference method employing a heating acid digestion (with a mixture of HCl, HClO4, and HF) using statistical tools. The best results were obtained using an extraction time of 10 min and a temperature of 25°C. Inductively coupled plasma optical emission spectrometry was applied for element quantification. Conclusion The proposed extraction method showed good results for Cu, Mn, Ni, Sr, and Zn. Furthermore, the proposed method based on ultrasound radiation presents additional criteria that align with the concepts of green analytical chemistry. Highlights A greener alternative method for the determination of Cu, Mn, Ni, Sr, and Zn in fluorescent lamp waste was developed. Optimal conditions for ultrasound extraction of potentially toxic elements were achieved in 10 min at a temperature of 25°C. Environmentally friendly aspects of ultrasound align with the requirements of green analytical chemistry. [ABSTRACT FROM AUTHOR]

[Display omitted] The commonly used artificial light sources, such as fluorescent lamps and white light-emitting diodes, often have a high ratio of blue light emission, which poses potential blue light hazards, especially one of the main culprits leading to eye diseases. Therefore, developing novel white lighting sources with low blue-hazard is highly appreciated. In this work, an air-stable and color-tunable triplet–triplet annihilation upconversion (TTA-UC) mechanism was proposed to realize the low blue-hazard white-light emission. The proposed design was composed of three primary RGB colors from the annihilator (9,10-diphenylanthracene, DPA), the laser excitation source, and the photosensitizer (palladium (II) octaetylporphyrin, PdOEP), respectively. The introduction of oil-in-water (o/w) microemulsion can effectively block the potential oxygen-induced triplet-quenching and benefit high UC efficiency. Moreover, either raising ambient temperatures or adding isobutanol can activate the UC process to yield white-light emission. Notably, the white-light emission with a Commission Internationale de l'Eclairage (CIE) coordinate of (0.33, 0.33) as well as a low ratio of blue emission (14.2 %) was achieved at an ambient temperature of 42 °C. Therefore, the proposed air-stable TTA-UC mechanism can significantly lower the blue-hazard and provide a novel solution for applications in lighting and display. [ABSTRACT FROM AUTHOR]

Electrical transformers are generally designed to operate from sinusoidal sources. However, increased use of nonlinear loads, such as electric motor drives, lighting, fluorescent lamps, rectifiers, and computers, which generate high values of harmonics, makes this transformer operate in the nonlinear region. This paper discusses and focuses on the effect of the characteristics of a single-phase transformer when it is operated from a non-sinusoidal source with a non-linear load. An experimental 1 kVA single-phase transformer with a voltage of 220V and frequency of 50Hz with linear and nonlinear loads was considered. The results of this investigation show the losses increased by 25% when the transformer was fed from a sinusoidal power supply and the load was non-linear. In addition, the losses and THD for the current reached 40% and 12.4%, respectively, at nearfull load when the transformer was fed from a non-sinusoidal power supply and non-linear loads. The correlation between total harmonic distortion (THD) and these types of power supplies and loads was illustrated. The results showed that increasing the current harmonic distortion will lead to increased transformer losses and thus reduce their life expectancy. [ABSTRACT FROM AUTHOR]

In order to address the energy challenges of the near future, researchers are currently focused on developing environmentally friendly and energy-efficient phosphors for luminescence devices such as light-emitting diodes (LEDs). When it comes to this topic, older lighting devices such as halogen lamps, LCD backlights, incandescent lamps, and fluorescent lamps can be substituted with advanced next-generation lighting technology created with phosphor-transformed white LEDs. We've conducted a detailed analysis of the structural and optoelectronic characteristics of Cs-based phosphors Cs2MF6 (M = C, Ge, Pb, Si) for potential use in photoluminescence as well as photovoltaic applications such as LEDs. Utilizing the GGA scheme allows for an in-depth analysis of exchange and correlation energy potentials within density functional theory (DFT) first-principles calculations. The calculated structural properties reveals that Cs2PbF6 is the most stable compound among Cs2MF6 (M = C, Ge, Pb, Si) as they possess lowest ground state energy. Direct bandgaps of 1.57, 1.459, 1.481, and 1.59 eV are observed with the presence of intermediate bands for Cs2CF6, Cs2GeF6, Cs2PbF6, and Cs2SiF6, respectively. It is established by analyzing plots that the investigated hexafluorides absorb maximum photons in the UV region. Based on the spectra, it is evident that Cs2MF6 (M = C, Ge, Pb, Si) act as weak reflectors of incident photons in the visible and IR regions. However, around 40% of the incoming photons get reflected at various energies by individual compounds. Thermodynamic characteristics of these hexafluorides reveals that they are thermodynamically stable compounds. [ABSTRACT FROM AUTHOR]

Mercury is one of the main components of fluorescent lamps. Considering the adverse effects of mercury on human health and the environment, recovery of mercury-containing fluorescent lamps is very important in developed countries. The glass parts of used fluorescent lamps are among the dangerous wastes whose mercury content should be reduced to the lowest possible level according to international standards. The aim of this research is to achieve a systematic approach to minimize the amount of mercury present in fluorescent lamp glass residues according to the European Commission EC95/2002 regulations. In order to extract mercury from glasses, glass pieces were washed with deionized water, using stirring to increase washing efficiency. In order to achieve the maximum amount of extraction, parameters such as ratio of glass to deionized water (S/L), stirring time, temperature and pH were changed. The results showed that, the highest mercury extraction rate is about 98% and in the conditions S/L = 0.1, stirring time of 12 h, temperature of 60 °C and pH 1, which is using a combination of HCl and H3PO4 acid 5% with a ratio of 1:4 has been obtained. The success of this method not only increases environmental sustainability, but also classifies the resulting glass waste as non-hazardous. [ABSTRACT FROM AUTHOR]

Lighting makes up 17% of electrical loads and the largest energy end use in commercial buildings. Linear fixtures are among the largest opportunities for energy efficiency improvement, given their long operating hours. With continued, rapid light-emitting diode (LED) development and more LED replacement products on the market, lighting replacement decisions become more complex and warrant re-examination. With a goal to inform building managers and other decision-makers with practical guidance on lighting replacement, this study is a life cycle cost (LCC) analysis that compares the cost–benefit of six replacement options (one fluorescent and five LED) for a 0.61 m by 1.22 m (2 ft by 4 ft) T8 recessed troffer based on data for 168 lighting products from an online vendor. Results show that direct wire (i.e. unballasted) LED retrofits are the least-cost option to replacing fluorescent lamps in terms of normalized LCC. Plug-and-play lamps suffer from a lock-in with ballasts, but their ease of installation can help spur LED adoption. In cases where an existing ballast is still usable, hybrid LED retrofits provide the least upfront cost option by deferring the cost of rewiring. LED luminaires can offer improved aesthetics and reliability; however, they have high upfront cost. Among them, luminaires with replaceable lamps offer lower cost than those without. [ABSTRACT FROM AUTHOR]

Rare-earth elements (REEs) are critical to our modern economy, yet their mining from natural ores bears a profound environmental impact. Traditional separation techniques are chemical and energy-intensive because their chemical similarities make REEs very challenging to purify, requiring multiple extraction steps to achieve high purity products. This emphasizes the need for sustainable and straightforward separation methods. Here we introduce a strategy for the direct separation of europium (Eu) from complex mixtures under ambient conditions, leveraging on the redox non innocence of purely inorganic tungsten tetrathiolate (WS42−) ligands. The recovery of Eu is achieved upon reduction of Eu(III) to a Eu(II) coordination polymer, driven by an induced internal electron transfer from the tetrathiotungstate ligand. Applying this strategy to unconventional feedstock such as spent energy-saving lamps allows selective europium recovery with separation factors over 1000 and recovery efficiency as high as 99% without pre-treatment of the waste. Rare-earth elements (REEs) are vital to the modern economy, yet their mining poses both geopolitical and environmental challenges. Here, authors present a highly selective method for the recovery of europium from spent fluorescent lamps using redox active tetrathiotungstate ligands. [ABSTRACT FROM AUTHOR]

Currently, the hazardous potential of spent fluorescent lamps due to their mercury content, which usually exceeds the limit allowed by standards, it is well known. When these are taken out from use, mercury is distributed between all the components of the lamp; in particular, it can be found in the phosphorescent powder called "phosphor" which is attached as a thin layer on the walls of the lamps. Although many efforts have been made to develop technologies for recovery of mercury, in many cases their effectiveness is very hard to be proved from both technical and economic points of view. Therefore, this work is focused on evaluating the feasibility of valorizing this type of waste glass as an active precursor for the synthesis of fly ash-based alkali-activated materials. In this respect, the potential of synthesized alkali-activated materials to immobilize mercury from waste glass added to the synthesis mixture was experimentally proved through compliance leaching tests. Important microstructural changes that appear with the increasing addition of waste glass to the synthesis mixture were highlighted by SEM and N2-BET analysis. Sharp increase in the SiO2/Al2O3 molar ratio of the synthesis mixture with the increasing addition of waste glass leads to an increase in the unreacted glassy fraction that acts as defect sites in the structure of the alkali-activated material, having a negative effect on its mechanical properties. However, the compressive strength tests showed that an addition of waste glass up to 5% of the total mass of the synthesis mixture has a beneficial effect on the compressive strength of alkali-activated materials. [ABSTRACT FROM AUTHOR]

Plant in vitro cultures can be an effective tool in obtaining desired specialized metabolites. The purpose of this study was to evaluate the effect of light-emitting diodes (LEDs) on phenolic compounds in Rhaponticum carthamoides shoots cultured in vitro. R. carthamoides is an endemic and medicinal plant at risk of extinction due to the massive harvesting of its roots and rhizomes from the natural environment. The shoots were cultured on an agar-solidified and liquid-agitated Murashige and Skoog's medium supplemented with 0.1 mg/L of indole-3-acetic acid (IAA) and 0.5 mg/L of 6-benzyladenine (BA). The effect of the medium and different treatments of LED lights (blue (BL), red (RL), white (WL), and a combination of red and blue (R:BL; 7:3)) on R. carthamoides shoot growth and its biosynthetic potential was observed. Medium type and the duration of LED light exposure did not affect the proliferation rate of shoots, but they altered the shoot morphology and specialized metabolite accumulation. The liquid medium and BL light were the most beneficial for the caffeoylquinic acid derivatives (CQAs) production, shoot growth, and biomass increment. The liquid medium and BL light enhanced the content of the sum of all identified CQAs (6 mg/g DW) about three-fold compared to WL light and control, fluorescent lamps. HPLC-UV analysis confirmed that chlorogenic acid (5-CQA) was the primary compound in shoot extracts regardless of the type of culture and the light conditions (1.19–3.25 mg/g DW), with the highest level under R:BL light. BL and RL lights were equally effective. The abundant component was also 3,5-di-O-caffeoylquinic acid, accompanied by 4,5-di-O-caffeoylquinic acid, a tentatively identified dicaffeoylquinic acid derivative, and a tricaffeoylquinic acid derivative 2, the contents of which depended on the LED light conditions. [ABSTRACT FROM AUTHOR]

Over the past few years, light‐emitting diodes (LEDs) have emerged as an efficient replacement for standard incandescent and fluorescent lamps, due to their superior efficiency, energy conservation, service longevity, reliability, and affordability. However, identifying a red emitter for white LEDs has presented significant challenges. This study seeks to synthesize and analyze a novel red emitter, investigating its potential use in white LEDs and indoor plant growth lighting. The Sr2Lu(Nb,Mn)O6 is manufactured employing the traditional high‐temperature solid‐phase method. The internal and external quantum efficiencies (IQE and EQE) of double perovskites reached 32.39% and 21.67%. The g value calculates to 2.146, which corroborates that the magnetic dipolar transitions of Mn4+ ions inhabit symmetric octahedral sites. First‐principles investigations are utilized to unveil local electronic structures. Emission spectra reveal a substantial broad red emission peak at 688 nm. The Tanabe–Sugano diagram is applied to understand the luminescence mechanism. Additionally, the evaluation of parameters such as the internal UV emission ratio, crystal field strength, and Racah parameters is conducted. The luminescent intensity of the Sr2Lu(Nb,Mn)O6 can still be maintained at 60% upon reaching a temperature of 423 K. The findings suggest that Sr2Lu(Nb,Mn)O6 offers a novel alternative for white LEDs and indoor plant growth lighting. [ABSTRACT FROM AUTHOR]

• LED light at 610 nm negatively impacts the survival of dopamine neurons in culture. • 610 nm LED light damages mouse mesencephalic and hiPSC-derived dopamine neurons. • Elevated dopamine in differentiated MN9D cells increases vulnerability to light. • 610 nm LED light increases ROS production in differentiated MN9D cells. • MN9D co-treatment with H2O2 boosts light induced ROS production and cytotoxicity. Our recent study revealed that fluorescent lamp light can penetrate deep into the brain of mice and rats leading to the development of typical histological characteristics associated with Parkinson's disease such as the loss of dopamine neurons in the substantia nigra. Monochromatic LED lights were thus used in this work to deepen our knowledge on the effects of the major wavelength peaks of fluorescent light on mouse and human dopaminergic cells. In particular, we exposed immortalized dopaminergic MN9D neuronal cells, primary cultures of mouse mesencephalic dopaminergic cells and human dopaminergic neurons differentiated from induced pluripotent stem cells (hiPSC) to different LED light wavelengths. We found that chronic exposure to LED light reduced overall undifferentiated MN9D cell number, with the most significant effects observed at wavelengths of 485 nm and 610 nm. Moreover, LED light especially at 610 nm was able to negatively impact on the survival of mouse mesencephalic dopaminergic cells and of human dopaminergic neurons derived from hiPSC. Notably, differentiated MN9D dopaminergic cells, which closely resemble mature dopamine neuronal phenotype, acutely exposed for 3 h at 610 nm, showed a clear increase in ROS production and cytotoxicity compared to controls undifferentiated MN9D cells. These increases were even more pronounced by the co-treatment with the oxidative agent H 2 O 2. Collectively, these findings suggest that specific wavelengths, particularly those capable of penetrating deep into the brain, could potentially pose an environmental hazard in relation to Parkinson's disease. [ABSTRACT FROM AUTHOR]

This study describes the in vitro regeneration of 'Haruka' plants, a new cultivar of Japanese flowering cherry registered in 2021 by the Japanese statutory authority. As this is a double-flowered cultivar produced by inter-specific hybridization, in vitro regeneration is an effective method for large-scale propagation. To promote proliferation, apical shoots were cultured on half-strength Murashige and Skoog medium supplemented with 5 μM 6-benzylaminopurine. The highest average of 7.8 shoots per explant was obtained at 15°C in the dark. Cultures were maintained in continuous darkness for 12 wk and then transferred to lighting conditions under a 16-h photoperiod at 25°C. Subsequently, a 100% rooting rate was obtained with the application of 1 μM indole-3-butyric acid in combination with 0.1 μM naphthaleneacetic acid. Additionally, the number of roots per shoot and the maximum length of roots were significantly higher under exposure to pink light illumination provided by cold cathode fluorescent lamps emitting red- and blue-colored light at a ratio of 80% and 20%, respectively. More than 95% of the regenerated plantlets survived after ex vitro acclimatization. [ABSTRACT FROM AUTHOR]

Wind energy holds potential for in-situ powering large-scale distributed wireless sensor nodes (WSNs) in the Internet of Things (IoT) era. To achieve high performance in wind energy harvesting, a coaxial counter-rotating triboelectric nanogenerator with lift–drag hybrid blades, termed CCR-TENG, has been proposed. The CCR-TENG, which can work in non-contact and soft-contact modes, realizes low-speed wind energy harvesting through a combination of counter-clockwise rotating lift-type blades and clockwise rotating drag-type blades. Non-contact CCR-TENG realizes low-speed wind energy harvesting at wind speeds as low as 1 m/s. The output of a CCR-TENG, working in soft-contact mode, achieves 41% promotion with a maximum short-circuit current of 0.11 mA and a peak surface power density of 6.2 W/m2 with two TENGs connected in parallel. Furthermore, the power density per unit of wind speed achieves 746 mW/m3·s/m. Consequently, two fluorescent lamps were successfully illuminated and six temperature sensors were continuously lit by the CCR-TENG. The reported CCR-TENG significantly improves low-speed environmental wind energy utilization and demonstrates broad application prospects for in-situ power supply of distributed wireless transmission devices and sensors in the era of the IoT. [ABSTRACT FROM AUTHOR]

[Display omitted] • NH 4 -13X zeolite was tested for the recovery of REEs. • The solutions used mimic the leaching liquors of spent fluorescent lamps. • NH 4 -13X zeolite revealed a good affinity towards REEs. • Ce and La have a higher affinity for the zeolite than both NH 4 and Na. • NH 4 -13X zeolite is selective toward REEs with larger ionic radii. The constantly increasing demand of Rare Earth Elements (REEs) made them to be part of the so-called "critical elements" indispensable for the energy transition. The monopoly of only a few countries, the so-called balance problem between demand and natural abundance, and the need to limit the environmental costs of their mining, stress the necessity of a recycling policy of these elements. Different methods have been tested for REEs recovery. Despite the well-known ion-exchange properties of zeolites, just few preliminary works investigated their application for REEs separation and recycle. In this work we present a double ion exchange experiment on a NH 4 -13X zeolite, aimed at the recovery of different REEs from solutions mimicking the composition of liquors obtained from the leaching of spent fluorescent lamps. The results showed that the zeolite was able to exchange all the REEs tested, but the exchange capacity was different: despite Y being the more concentrated REE in the solutions, the cation exchange was lower than less concentrated ones (16 atoms p.u.c. vs 21 atoms for Ce and La solutions), suggesting a possible selectivity. In order to recover REEs from the zeolite, a second exchange with an ammonium solution was performed. The analyses of the zeolites show that almost all of Ce and Eu remain in the zeolite, while nearly half of La and Y are released. This, once again, suggests a possible selective release of REEs and open the possibility for a recovery process in which Rare Earths can be effectively separated. [ABSTRACT FROM AUTHOR]

The emergency lighting system (ELS) is mandatory to be installed at the commercial, residential, and public buildings and must be activated automatically in the case of disasters such as fire, earthquake, flood, hurricane, and electricity power outage situations. Conventional ELS must use an extra phase line to charge its battery as well as to detect the presence of an emergency condition. It is costly to use an additional phase line in the electrical system and requires a new system configuration in the existing systems. In this study, an ELS design is proposed that eliminates the need for additional phase line installation by using power line communication (PLC) circuitry. Additionally, LED lamp is preferred instead of fluorescent lamp due to their advantages. The proposed ELS detects the presence of emergency and power outage conditions and then charges the battery of the system through the PLC. [ABSTRACT FROM AUTHOR]

Rare earth elements (REEs), one of the global key strategic resources, are widely applied in electronic information and national defense, etc. The sharply increasing demand for REEs leads to their overexploitation and environmental pollution. Recycling REEs from their second resources such as waste fluorescent lamps (WFLs) is a win-win strategy for REEs resource utilization and environmental production. Pyrometallurgy pretreatment combined with acid leaching is proven as an efficient approach to recycling REEs from WFLs. Unfortunately, due to the uncontrollable components of wastes, many trials were required to obtain the optimal parameters, leading to a high cost of recovery and new environmental risks. This study applied machine learning (ML) to build models for assisting the leaching of six REEs (Tb, Y, Eu, La, and Gd) from WFLs, only needing the measurement of particle size and composition of the waste feed. The feature importance analysis of 40 input features demonstrated that the particle size, Mg, Al, Fe, Sr, Ca, Ba, and Sb content in the waste feed, the pyrometallurgical and leaching parameters have important effects on REEs leaching. Furthermore, their influence rules on different REEs leaching were revealed. Finally, some verification experiments were also conducted to demonstrate the reliability and practicality of the model. This study can quickly get the optimal parameters and leaching efficiency for REEs without extensive optimization experiments, which significantly reduces the recovery cost and environmental risks. Our work carves a path for the intelligent recycling of strategic REEs from waste. [ABSTRACT FROM AUTHOR]

Plants, whilst also having an ornamental role, are also a source of beneficial, bioactive compounds, and in vitro cultures are helpful in finding and obtaining them. Streptocarpus ×hybridus can be a source of antioxidants. The effect of different LED light qualities on the growth, development and metabolite composition of Streptocarpus multiplied in vitro on Murashige and Skoog medium was investigated. The used spectra were: 100% blue (B), 100% red (R), red and blue in 7:3 proportion (RB), 50% RB + 50% ultra violet (RBUV), 50% RB + 50% green (RBG), 50% RB + 50% yellow (RBY), 50% RB + 50% far red (RBfR), and white (WLed). A fluorescent lamp served as the control (Fl). For the best morphological quality of multiplied plants, the use of RBY light is recommended. Fl light reduced the antioxidant properties of extracts compared to LEDs. The most recommended spectrum in this aspect is RBfR, WLed, RBG and R light. These lights (except for R) stimulated the polyphenol content. RBY and R light influenced the highest content of free amino acids and reducing sugars. Studies showed that a selected LED light spectrum can influence the production of plant biomolecules with antioxidant properties and, compared to Fl light, improves the growth and development of multiplied plants. [ABSTRACT FROM AUTHOR]

In the aquaculture feed industry, the batch cultivation of the alga Chlorella ellipsoidea is frequent because it allows the control of factors contributing to product quality. In this study, we conducted batchcultivation experiments in a smart algae cabinet with 4 different light intensities, 1,000, 3,000 and 5,000 Lux, as well as a fluorescent lamp (8,000 Lux). The growth curves, specific growth rate and biomass productivity of C. ellipsoidea provided with the BG-11, Bold and Chu-13 nutrient formulae were evaluated. The results revealed biomasses of 1.315 ± 0.0087, 1.042 ± 0.0063 and 1.096 ± 0.0036 g/L/day and specific growth rates of 0.979 ± 0.0067, 0.7453 ± 0.0060 and 0.7781 ± 0.0026 per day for the 3 formulae, BG-11, Bold and Chu-13, respectively. The mean biomasses of C. ellipsoidea grown on BG-11 at all light intensities were significantly higher than those for other media (p-value = 0.0001). With the log phase achieved in 3 days, BG-11 was more suitable for rearing at all tested light intensities, while Chu-13 was only applicable at 5,000 Lux. Using all 3 light intensities, it was possible to reduce the log-phase of algae growth from 7 to 3 days and increase biomass by more than 1.2 times when compared to fluorescent light culture. [ABSTRACT FROM AUTHOR]

The article presents the results of a study of new ceramic materials φ-Bi8Pb5O17 obtained by pyrolysis using mannitol C6H14O6 as a reducing fuel. The values of the band gap of the obtained compositions are determined by analyzing the diffuse reflectance spectra using the Tauc construction. They are in the range from 2.57 to 2.67 eV, which corresponds to visible light photocatalysts. The degree of degradation of methylene orange when using synthesized samples ranged from 95 to 99% when irradiated for 3 h with a fluorescent mercury lamp. [ABSTRACT FROM AUTHOR]

[Objective] This study explored the effects of different green light intensities on development of Ectropis grisescens Warren to provide support for the green prevention and control of E. grisescens in tea plantations. [Method] The first instar larvae of the fifth generation of E. grisescens, which were reared in the room with fresh leaves, were treated with green light with intensities of 40, 80, 120, 140, 240 and 340 lx at wavelengths of 520-525 nm. There were 7 treatments in total including the control with 80 larvae in each treatment. The green light groups were irradiated by general fluorescent lamp (150-200 lx) for 12 hours during the day and by green light for 12 hours at night, while the control group was irradiated by general fluorescent lamp (150-200 lx) for 12 hours during the day and remained darkness for 12 hours at night. The effects of green light intensity on larval development duration, survival rate, pupa quality, pupation rate, adult emergence rate, adult longevity, duration of oviposition, female fecundity and hatching rate of E. grisescens were determined. [Result] With the increase of light intensity, the total developmental duration of E. grisescens larvae was shortened, among which 240 and 340 lx treatments were significantly different from the control. The survival rate of the 5th instar larvae of E. grisescens was decreased. Except for 40 lx, the pupation rates of E. grisescens of other treatments were significantly lower than that of the control. Compared with the control, the quality of male and female pupae decreased under different light intensities, and the quality of male pupae was lower than that of female pupae. With the increase of light intensity, the eclosion rate of E. grisescens adults decreased, and the green light treatments of 120, 140, 240 and 340 lx were significantly different from the control. The longevity of adults treated with 240 and 340 lx green light was significantly shortened, the maximum and average egg production per female was significantly decreased, and the oviposition duration was significantly shortened. Compared with the control, the hatching rate of eggs treated with different light intensities was significantly decreased with the lowest value of 17.00%. [Conclusion] The treatments with green light intensities of 240 and 340 lx significantly shortened the developmental duration of larvae and adult longevity, decreased eclosion rate, female fecundity and hatching rate, and thus inhibited the development of the population. It can be concluded that these two kinds of intensity green light can effectively prevent and control the E. grisescens warm. [ABSTRACT FROM AUTHOR]

Electronic (e-)waste viz. the spent fluorescent lamps can be a rich source of rare earth elements (REEs) for the secondary supply of them. This article reports a comparative study on mineral acid leaching and, then, compared an alkali diffusion-acid leaching process for higher efficiency of yttrium and europium. Using a direct acid leach process, 2 M HNO3 yielded a better dissolution efficiency of REEs at the moderate temperature of 60°C and in the presence of H2O2in comparison to 91% and 87% leaching efficiency with 2.0 M H2SO4. On the other hand, the alkali-fused phosphor mass leached in 2.0 M H2SO4 without H2O2 addition showed remarkable progress in dissolution efficiency, yielding >99% and >98% of yttrium and europium in the leach liquor. Furthermore, the leaching kinetics of the alkali-diffused phosphor showed the best fit with the logarithmic rate law. The apparent activation energy was calculated to be 43.3 kJ/mol and 35.1 kJ/mol for yttrium and europium, indicating two different mechanisms during the leaching process by following the chemical- and diffusion-controlled reactions, respectively. [ABSTRACT FROM AUTHOR]

The article presents the results of a study of new ceramic materials φ-Bi8Pb5O17 obtained by pyrolysis using mannitol C6H14O6 as a reducing fuel. The values of the band gap of the obtained compositions are determined by analyzing the diffuse reflectance spectra using the Tauc construction. They are in the range from 2.57 to 2.67 eV, which corresponds to visible light photocatalysts. The degree of degradation of methylene orange when using synthesized samples ranged from 95 to 99% when irradiated for 3 h with a fluorescent mercury lamp. [ABSTRACT FROM AUTHOR]

The discarding of spent fluorescent lamps, one of the most significant sources of mercury usage in industry, might cause mercury release into the environment when suffering from breakage. The reclamation disposal of fluorescent lamps for mercury recycling is essential, while how to achieve highly efficient conversion of various mercury species into elemental mercury vapor is a key challenge. Herein, the distillation method was adopted for mercury recycling from phosphor powder. The results show that the contents of elemental mercury and oxidized mercury vapor filled in the lamps were 150–3500μgand 5–20μg, respectively. The mercury release sustained for 13(±2) h, with a maximum mercury concentration of 4500μg/m3. The mercury in phosphor can be desorbed to an undetected level when distilling at 600 °C under vacuum for 30 min, while that would be achieved at 700 °C when distilling under atmospheric pressure. This suggests that the vacuum distillation was favorable for the conversion of oxidized mercury into elemental mercury. The variation of mineral phase, particle size distribution and morphology of phosphor after distillation was insignificant, which guaranteed the recycling of phosphor simultaneously accompanying with mercury recycling. This work clarified the mercury release behavior during lamps crushing and provided a feasible way for mercury recycling.

Phototherapy converts lipophilic unconjugated bilirubin to hydrophilic bilirubin photoisomers, such as lumirubin. We comparatively used a blue light-emitting diode (LED) and a green fluorescent lamp (FL) as light sources for phototherapy of hyperbilirubinemic preterm neonates with the aim of examining potential differences in urinary lumirubin excretion between these two wavelengths. Urinary lumirubin levels were measured using a fluorescence assay with blue light exposure in the presence of the unconjugated bilirubin-inducible fluorescent protein UnaG, and denoted as urinary UnaG-bound bilirubin (UUB)/creatinine (Cr) (μg/mg Cr). Preterm neonates born at ≤ 33 weeks gestational age and treated with phototherapy were subjected to this study. The maximum UUB/Cr level during phototherapy per device intensity was compared between neonates treated with the blue LED and the green FL. A total of 61 neonates were examined to determine the maximum UUB/Cr levels. The median of maximum UUB/Cr excretion per light intensity of each device (μg/mg Cr/μW/cm2/nm) was 0.83 for the blue LED and 1.29 for the green FL (p = 0.01). Green light was found to be more effective than blue one for bilirubin excretion via urinary lumirubin excretion. This is the first spectroscopic study to compare the efficacy of phototherapy at different wavelengths using fluorescence assay. [ABSTRACT FROM AUTHOR]

Korean bellflower (Campanula takesimana Nakai) is a rare and perennial herb with medicinal and ornamental values, is endemic to the Ulleung Island of Korea. In this study, we investigated the dormancy-release and germination characteristics of C. takesimana (Campanulaceae) seeds by subjecting them to varying temperatures (5, 10, 15, 20, and 25°C and diurnal/nocturnal temperatures of 15/6, 20/10, and 25/15°C), cold stratification periods (0, 4, 8, or 12 weeks at 5°C), and gibberellic acid (GA3) concentrations (0, 10, 100, or 1,000 mg·L-1 at 15/6°C and 25/15°C) to identify the ideal seed propagation conditions. The seeds were stimulated to germinate (at 25°C, 12-h photoperiod with fluorescent lamps at 40 ± 10 μmol∙m-2∙s-1) after cold stratification. To examine the germination characteristics, the seeds were tested for water imbibition and found to readily absorb water. The seeds exhibited underdeveloped embryos during dispersal, showed final germination of 37.00% ± 4.43 at 25°C and were not influenced by temperature. The seeds subjected to 0, 4, 8, or 12 weeks of cold stratification germinated at a success rate of 22.00% ± 4.76, 87.00% ± 6.80, 79.00% ± 2.52, and 77.00% ± 1.91, respectively. Additionally, the germination characteristics, which were based on final germination, mean germination time, and germination velocity (Timson index), were significantly greater in the seeds pretreated with 1,000 mg·L-1 GA3 at 25/15°C than in seeds pretreated with 0 mg·L-1 GA3. Overall, the seeds broke dormancy with GA3 and short-term cold stratification. Therefore, we concluded that C. takesimana seeds have non-deep, simple, morphophysiological dormancy, and pretreatment with cold stratification and GA3 is required for effective seed propagation. [ABSTRACT FROM AUTHOR]

Addressing the issue of system stability is a crucial step towards the successful integration of memristive devices in power electronics applications. This paper focuses on fluorescent lamps possessing memristive characteristics and investigates the instability phenomena and mechanisms within a full-bridge inverter with a fluorescent lamp load. Based on the memristive characteristics of fluorescent lamps, this paper establishes the averaged model of the system, whose coefficient matrix is nonlinear, periodic, and time-varying. This study identifies the occurrence of low-frequency oscillations within the system and elucidates the fundamental mechanism underlying the emergence of low-frequency oscillations. Furthermore, this paper establishes the stability boundaries of the system across different parameter planes. The research findings indicate that the low-frequency oscillations within the system are attributed to the occurrence of Hopf bifurcations in a frequency range higher than line frequency but significantly lower than switching frequency. Lastly, the PSpice circuit of the system is designed, and simulation results are provided for validation. This study can offer guidance on parameters and control strategies for ensuring the stable operation of a full-bridge inverter with fluorescent lamps. Moreover, it can facilitate the comprehension of instability mechanisms in systems incorporating memristive devices, thereby offering a foundation for the expansion of memristor applications. [ABSTRACT FROM AUTHOR]

We studied an electric breakdown in an 80-cm-long discharge tube with the inner diameter of 1.5 cm (the so-called "long discharge tube") in xenon at 1 Torr. The discharge was initiated by positive pulses of ramp voltage with a rise rate dU/dt on the order of 10–1–105 kV/s. The breakdown voltage was measured in darkness and upon tube illumination by fluorescent lamps, LEDs, or a diode laser. The effect of illumination depends on the slope of the pulse leading edge. The voltage drops at dU/dt > 100 kV/s, while growing at dU/dt < 100 kV/s. The voltage increases by a factor of six for the voltage slope of 0.1–1 kV/s. The dependence of the observed effect on radiation intensity, wavelength, and position of the illuminated area on the tube surface is studied. The pre-breakdown ionization wave behaves unusually under the described conditions: its speed and intensity of emission at its front grow in the course of wave propagation. Photodesorption of electrons from the tube surface as a result of which the wall near the anode becomes positively charged is assumed to represent the mechanism of the observed phenomena. This causes an increase in the breakdown voltage and accelerated propagation of the ionization wave. Additional experiments confirm the presence of the wall charge in the near-anode region under the discussed conditions. [ABSTRACT FROM AUTHOR]

Three novel donor–acceptor–acceptor configured small molecules with benzotriazole as the central A building block are synthesized as donor materials for vacuum‐deposited small‐molecule organic solar cells (SMOSCs). The effects of different lengths of the side chains attached to the benzotriazole block on the molecular structure, electrochemical behavior, and optical properties of these donors are investigated systematically. Vacuum‐deposited SMOSCs fabricated with these small molecule donors and C70 as the acceptor exhibit power conversion efficiencies (PCEs) in the range of 6.42–7.43% under air mass 1.5 global (AM 1.5 G) 100 mW cm−2 simulated solar illumination. Furthermore, the Me‐DTDCPT‐based devices deliver a promising PCE of 14.84% under 600 lux illumination by a fluorescent lamp, demonstrating its potential in indoor photovoltaic applications. [ABSTRACT FROM AUTHOR]

Copyright of Przegląd Elektrotechniczny is the property of Przeglad Elektrotechniczny 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.)

Plasma antennas have promising prospects for practical use with quick changes in their parameters in a wide frequency range. In this work, the radiation pattern of a plasma antenna system, which consists of a short linear antenna surrounded by fluorescent lamps, is analyzed in a frequency range of 0.5–1.5 GHz. In numerical simulation, the parameters of the gas-discharge plasma were used, which were obtained using the drift theory. In addition, an analysis of the radiation patterns using a simple and intuitive ring antenna array model was carried out, and the limit of its applicability was demonstrated. The experimental data were compared with those of simulation and theoretical analysis. Finally, a simulation was performed to compare the plasma antenna system with its metal counterpart. The results obtained are important for a whole class of nested antenna systems. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Mine Automation is the property of Industry & Mine Automation Editorial Department 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.)

Copyright of Gestión y Ambiente is the property of Universidad Nacional de Colombia 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.)

Plant tissue culture and novel breeding techniques such as genome editing in the economically important crop Arachis hypogaea constitute potential for genetic improvement. Therefore, in this study, high-frequency in vitro regeneration via formation of adventitious shoots was described for different A. hypogaea lines. The leaflets of the primary leaves of 5-day-old seedlings were cultured for 16 weeks on Murashige and Skoog's medium supplemented with equimolar concentrations (22.19 µM) of the cytokinins 6-benzylaminopurine (BAP); thidiazuron (TDZ); zeatin (Zea) or meta-topolin (MT), which was reduced to 7.40 µM after eight weeks plus 2.3 µM kinetin. Highest shoot regeneration percentages of 89.1% and 81.3% for BAP and TDZ containing media, respectively, were achieved in the line 'Jimmy's pride' with the maximum shoot number obtained on BAP. The regeneration percentages for three further lines were lower than 50%. Furthermore, the effect of different light qualities, applied using LEDs, and compared to fluorescent lamps was investigated. Shoot regeneration percentages did not improve significantly under the different LEDs, instead a pronounced effect on the regeneration efficiency of the culture temperature was observed which differed among the light treatments. However, fluorescent lamps can be replaced by red or blue LEDs without negative effects on shoot regeneration. [ABSTRACT FROM AUTHOR]

Copyright of Revista Técnica Energía is the property of Centro Nacional de Control de Energia CENACE 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.)

The development of an exceptionally sensitive diagnostic technique for early identification of aquaculture diseases, specifically Aeromonas hydrophila, is essential for efficient management of disease outbreaks at aquaculture locations. In this research, a swift and sensitive diagnostic assay employing Loop-mediated isothermal amplification (LAMP) of Aeromonas hydrophila was devised and compared to the conventional qPCR method documented by Rong Wang. Validation of the diagnostic assay was carried out using actual samples obtained from aquaculture fish. The findings revealed that based on the rapid detection of crude bacterial genomic DNA, the fluorescent LAMP assay possessed a lower limit of detection (LOD) of 0.559 ng/μL (0.315–1.693, 95% CI), while the LOD for qPCR stood at 4.301 ng/μL (2.084–8.876, 95% CI). Both techniques demonstrated outstanding specificity, exhibiting no cross-reactivity with bacteria from the same or closely related genera. A total of 74 fish samples suspected to be infected with the fish disease were gathered, with 26 and 23 samples testing positive for Aeromonas hydrophila via LAMP and qPCR, respectively. The concordance analysis for LAMP and qPCR methods generated a Kappa value of 0.909 (0.778–1.000, 95% CI), signifying a high degree of diagnostic consensus. This study highlights that the LAMP assay eliminates the thermal cycle temperature change process of qPCR, uses lysate to crudely extract bacterial genomic DNA, and can complete the detection within 40 min, rendering it a practical and efficient alternative for monitoring disease outbreaks at aquaculture sites. [ABSTRACT FROM AUTHOR]

This article is focused on the application of plasma technology for the development of microwave lens antennas with electronically controllable radiation gain. With this aim, the analytical background and design procedure for designing a biconcave lens based on plasma dielectric material are presented. The procedure is used to design a plasma lens antenna with a pyramidal horn feed. The effect of switching the designed lens ON and OFF on the radiation gain of the lens antenna is investigated. It is also shown that the plasma frequency of the lens can be used to dynamically adjust the radiation gain. A one-dimensional version of the proposed plasma lens operating at 10 GHz has been developed to validate the concept. Experimentally measured characteristics of a fabricated prototype of the lens antenna based on commercially available fluorescent lamps confirm the presented design procedure and numerical results. The results also show that changing the plasma frequency of the lens can be used to adjust the radiation gain of the proposed lens antenna. [ABSTRACT FROM AUTHOR]

Background: Ultraviolet C (UVC) irradiation was used in the food industry as an environmentally friendly and safe defense against inducible biological elicitors. Turnips have an excellent nutritional profile. The aim of this research is to study the effect of UVC on the morphological structure and antioxidants of Turnips seeds. Methods: The seeds of Turnips red were received from the Egyptian Ministry of Agriculture, and used as research samples. The ultraviolet irradiation system consists of one fluorescent lamp (type- C) which is covered totally with aluminum foil to illuminate the sample from all sides. The total phenolic content was determined using the Florin–Ciocalteu method. The structure of the used samples was studied by x-ray and IR analysis. Results: The values of germination height and the weight for turnip red seeds after exposure to UV- C for 1, 2, 3 and 4 hours at 5, 15 and 15 cm from ultraviolet (UV) source are less than non-irradiated seeds. Total phenolic and anthocyanin content in Turnip red seeds increased after exposure to UV- C for 1, 2, 3 and 4 hours at 5, 15 and 15 cm distances from the UV source. Also, an internal structure such as the order or arrangement or position of Turnip red molecules changed after exposure to UVC. [ABSTRACT FROM AUTHOR]

For many years, conventional lighting booths with custom standard fluorescent lamps have been used in industry for color material testing and quality control. Particularly, lamps that simulate Illuminant D50 are used in imaging and graphics fields. For this study, a spectrophotometer system based on an LED-based spectrally tunable light source (LSTL) was developed to assess Illuminant D50 simulator quality effects on object color evaluation. The LSTL, which was constructed with 23 bands of LEDs in the ultraviolet (UV) – visible range, can simulate any spectrum accurately by control of each LED. Using this system, various grades of Illuminant D50 were simulated and irradiated on test white papers for direct and detailed evaluation of the effects of different grades, which was difficult when using earlier light sources. The relations between the effects of fluorescence generated using UV light and the MIuv grade were carefully investigated. In addition, the quality of practical Illuminant D50 simulators (D50 lamps and D50 LEDs) in manufacturing was discussed based on these study findings and improvements the practical simulators were suggested. These experiments also demonstrated that the developed system incorporating the LSTL has unprecedented power for use in direct evaluation of lighting source effects on the object color. [ABSTRACT FROM AUTHOR]

For many years, there has been a growing trend toward producing plants using tissue culture, the most efficient method at present. Every year, more and more protocols for micropropagation of economically valuable species are appearing. Many factors influence the regenerating explants under sterile laboratory conditions. One of the most important is light. The aim of the present study was to increase the efficiency of micropropagation of hellebore 'Molly's White' using energy-efficient light-emitting diodes (LEDs), which were compared to traditionally used fluorescent lamps (FLs). To choose the best light and reduce production costs, white, blue or red LEDs with two levels of photosynthetic photon flux density (PPFD), 40 and 70 μmol/m2/s, were used at the multiplication and rooting stages. LED light color has been shown to affect regeneration rate and plant growth in length during micropropagation, while both light parameters (color as well as intensity) affect the length of regenerating shoots and the content of assimilation pigments in plants. The use of white LED light, which gives the highest multiplication rate, at an intensity of 70 μmol/m2/s saves more than 57 kWh during an 8-week micropropagation cycle compared to conventional fluorescent lamps with the same parameters. [ABSTRACT FROM AUTHOR]

BACKGROUND: Chameleon diamond is a kind of color diamond with photochromic and thermochromic phenomenon. If the chameleon diamond is placed in a dark room or heated for a long time, it can change from greenish yellow to fancy yellow, and return to its original color when the diamond cools. Previous studies on chameleon diamond mainly focus on spectral characteristics. Through testing a large number of samples, the gemological and spectral characteristics of chameleon diamond are summarized. The characteristics of chameleon diamond, including persistent yellow phosphorescence, 480nm absorption band, mainly the A-aggregate of nitrogen, and proposed a model to explain the thermochromic and photochromic phenomenon of chameleon diamond.The characteristics of chameleon diamond discovered by previous studies are also found in a few yellow diamonds. Diamonds colored by the 480nm band shows yellow fluorescence and phosphorescence under short wave ultraviolet light, low nitrogen content, high concentrations of defects related to hydrogen and nickel, but no obvious thermochromic and photochromic phenomena. Previous studies of the chameleon diamond and similar yellow diamonds were separated and did not compare the two similar diamonds. OBJECTIVES: To ascertain the difference of spectral characteristics and defect types between chameleon diamonds and similar yellow diamonds and then analyze the causes of thermochromic phenomenon of chameleon diamond, and have a deeper comprehend of the possible structure of the center responsible of the chameleon effect. METHODS: Firstly, two chameleon diamond samples and four similar yellow diamond samples were collected to observe the color changes of the diamonds before and after heating. Top illumination and scattering illumination were used to observe the internal characteristics and color distribution of the samples. The fluorescence and phosphorescence characteristics of diamonds at long wave （365nm） and short wave （254nm） were observed by ordinary fluorescent lamp. The fluorescence and phosphorescent characteristics and growth structure of the samples under ultra-violet light were observed by Diamond View MT. Secondly, in order to investigate the causes of thermochromism in chameleon diamond, the absorption characteristics of diamond samples in the range of ultraviolet visible light were collected before and after heating, and compared with those of similar yellow diamonds. Analyze the differences in absorption spectra between chameleon diamond and similar yellow diamond, explore the causes of thermochromic phenomena. Finally, infrared spectrometer was used to collect the infrared spectrum of diamond samples and analysis of the types and impurity elements of diamond samples. Through the comparative analysis of the infrared spectrum of samples, the differences in the types and contents of nitrogen and hydrogen impurities between chameleon diamond and similar yellow diamond were obtained.The laser Raman spectrometer was used to collected PL spectra of the samples at liquid nitrogen temperature by using 473nm,532nm and 830nm lasers. By comparing the PL characteristics of chameleon diamond and similar yellow diamond, the differences between the two defects were obtained. RESULTS: The color distribution of the 6 diamond samples was uniform. After heating, the chameleon diamond samples changed color from yellow-green to yellow, similar yellow diamonds had no obvious color change. Under long and short wavelength UV light, the samples were yellow fluorescence without phosphorescence. The performance of the samples in this study is consistent under long and short wavelength ultraviolet light, but it is different from the previous study results that the chameleon diamond has persistent yellow phosphorescence, which further indicates that the chameleon effect is not directly related to the phosphorescence. Under ultra-violet light, the samples were all green fluorescence with irregular patterns which were markedly similar to diamonds colored by the480nm band. Chameleon diamonds showed moderate green phosphorescence. All the samples have C defect absorption continuum combines with of 480nm absorption band. The specific wide absorption band of 650-800nm is obvious in chameleon diamond. After being heated, the 480nm and 650-800nm absorption band of chameleon diamond completely disappeared. However, the 480nm absorption band of similar yellow diamonds is weakened or has no obvious change. Therefore, the poor thermal stability of 480nm and 650-800nm absorption band is responsible for the thermochromic phenomenon of chameleon diamonds. The infrared absorption characteristics of chameleon diamond mainly show A-center absorption, isolated nitrogen and hydrogen-related features can be seen. In addition to the characteristic 1430cm-1 wide absorption which has a different origin than the platelet-related1430cm-1 feature in Cape diamond. The similar yellow diamond has higher nitrogen content, and the degree of nitrogen aggregation is higher, and does not show any type Ib character. The broadband emission of all samples occurred mainly as one band centered at 700nm, this band consists of a dozen of peaks from 595nm to 725nm in steps of about 10nm.Additionally sharp peaks at 753,771,799,818,838,845nm present in the chameleon diamond samples. This spectrum is virtually identical to that reported previously for diamonds containing the 480nm absorption band. Chameleon diamonds and similar yellow diamonds all contain nitrogen-vacancy, nickel-nitrogen related defects, but the amount of defects are different. Chameleon diamonds cannot be effectively distinguished based on the PL spectral. The PL spectrum analysis showed that the nickel impurity was responsible for the green fluorescence of the samples under ultra-violet light. CONCLUSIONS: This study focuses on the comparative analysis of gemology, UV-visible absorption, infrared absorption and photoluminescence characteristics of chameleon diamond and its similar yellow diamond. Chameleon diamond is Ia diamond, the total nitrogen, as well as the A-center concentration, is relatively low, and show some type Ib character, such as 1240cm-1 absorption. Chameleon diamond has 480nm and 650-800nm absorption bands, that were responsible for chameleon effect. The characteristics of chameleon diamond in this study are roughly same as those in previous studies. Absorption bands of 650-800nm and absorption peaks of1430cm-1 （unrelated to platelet） are the main differences between the chameleon diamond and similar yellow diamond sample. It is inferred that the absorption band of 650-800nm and the absorption peak of 1430cm-1 are related to the center causing the thermochromic phenomenon. Although similar yellow diamond samples also have 480nm center, their thermal stability is different from that of chameleon diamonds. The reason for this phenomenon is unknown, therefor further studies are needed. [ABSTRACT FROM AUTHOR]

Light is a determining factor in plant morphophysiology, as it influences the growth and development of agricultural crops. Thus, the objective was to investigate the effects of light sources on the growth and development of "biquinho" pepper cultivars. The experiment was performed in two stages (Exp1 and Exp2), evaluating two cultivars (BRS Moema;Airetama biquinho) in five light sources (white LEDs, red LEDs, blue LEDs, red/blue LEDs, and fluorescent lamps). In Exp1 theplants were kept in a controlled condition, with a completely randomized design, in a 2x5 factorial scheme (cultivars x light sources) until 76 days after emergence (DAE), in which growth variables and photosynthetic pigments were evaluated. In Exp2, the plants were removed from the above conditions and transplanted in pots, being kept in greenhouse for more76 DAE. At 152 DAE, the same variables as Exp1 were evaluated, as well as gain of shoot fresh and dry mass, and gain of root fresh and dry mass. In both experiments, growth variables were affected by cultivar and the light sources, however, the behavior did not follow the same trend for all variables, indicating that the light quality influences the growthof the crops, and impacting during greenhouse conditions. [ABSTRACT FROM AUTHOR]