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In the current research, the rare earth‐doped magnesium aluminate (MgAl2O4:Eu3+) spinels were produced by the combustion synthesis method. The employment of thermodynamic calculations revealed that the combustion approach is a proper way to synthesize MgAl2O4:Eu3+ material by urea fuel, although this procedure was fulfilled at 500°C, the final temperature will be around 2030°C. The x‐ray and FT‐IR spectra confirmed the successful formation of spinels, while it was shown that the calcination procedure results in a significant increase of crystallinity. On the other hand, it was interestingly seen that the addition of large amounts of Eu3+dopant (10 wt%) suppresses the crystallinity. The MAUD calculations interestingly revealed that the increase of Eu3+ dopant from 1 to 10 wt% leads to the increase of MgO and Al2O3 impurities. The related microstructural evaluations revealed that the particle size of the synthesized powders is mostly less than 40 nm which shows the superiority of combustion synthesis over other commercial methods. Also, the broadening of XRD peaks confirmed the formation of nano‐sized powder. The photoluminescence (PL) characterizations showed that doping of MgAl2O4 with 7 wt% Eu3+ brings the most intensive emission properties at the wavelengths of 592 and 617 nm. [ABSTRACT FROM AUTHOR]

Conventional jet fuels derived from fossil sources contribute to greenhouse gas emissions and air pollution, leading to climate change. Recent studies have shown that biobased jet fuels from different feedstocks offer a more sustainable alternative to conventional fuels as they are derived from renewable biomass, reducing greenhouse gas emissions. The major feedstocks reviewed are jatropha curcas, camelina, karanja oil, waste cooking oil, and municipal solid waste. They offer diverse benefits for sustainable aviation fuel development. As a comparative analysis, this review examined jet fuel characteristics based on their physicochemical properties, namely energy content, viscosity, calorific value, cetane number, and freezing and flash points. The objective was to understand the influence of the properties on performance evaluation, environmental impact, and combustion characteristics. The properties of biojet fuels are compared with their fossil counterparts to validate their suitability as renewable alternatives and their benefits in terms of emissions reduction and engine performance. Biojet fuels perform better in terms of lower sulfur content, lower soot content, and a lower freezing point, their aromatic content, and their high cetane number. This study enhances the understanding of biojet fuels and their quality, and supports the development of sustainable fuel options. Overall, adherence to the American Society for Testing and Materials (ASTM) D7566‐18 standard is crucial for the acceptance and integration of biojet fuels into the aviation sector. Future research should explore feedstocks such as wood biomass, wastepaper, and agricultural residues for biojet fuels. It should also investigate the combustion and emission characteristics of biosourced aviation fuel at higher blending ratios (>50% by volume) with fossil Jet A‐1. [ABSTRACT FROM AUTHOR]

This study aims to address critical challenges such as global warming and energy sustainability by targeting the reduction of high NOx emissions in diesel engines. The effects of acetone (AC) and magnesium oxide (MgO) nanoparticles (NPs) as additives in improving the physicochemical properties of biodiesel derived from renewable, nonedible Pistacia terebinthus oil, which is abundant in Turkey and has a high free fatty acid (FFA) content of 5.8%, were investigated. Due to the high FFA content, a two‐step (esterification followed by transesterification [TR]) method was used for biodiesel production. Additionally, a quantitative analysis of biodiesel obtained by both single (TR) and two‐step methods was performed to address a gap in the literature. The addition of AC and MgO NPs to B20 (80% diesel fuel and 20% biodiesel) fuel resulted in reductions in the rate of pressure rise, instantaneous energy release, cylinder pressure, mean gas temperature, and cumulative heat release rate. However, brake‐specific fuel consumption increased, and brake thermal efficiency decreased. Emissions analyses showed a reduction in CO emissions by 6.65% with AC and 2.10% with AC + MgO, and a reduction in NOx emissions by 41.64% with AC and 46.03% with AC + MgO. However, hydrocarbon emissions increased by 26.48%. The study highlights the synergistic benefits of AC and MgO additives in biodiesel, presenting a viable strategy for improving the environmental and performance metrics of biodiesel blends. It provides new insights into alternative fuel formulations. [ABSTRACT FROM AUTHOR]

The precise preparation of hierarchical micelles is a fundamental challenge in modern materials science and chemistry. Herein, poly(di‐n‐hexylfluorene)‐block‐poly(3‐tetraethylene glycol thiophene) (poly(1m‐b‐2n)) diblock copolymers and polyfluorene‐block‐polythiophene‐block‐poly(phenyl isocyanide) triblock copolymers were synthesized using a one‐pot process via the sequential addition of corresponding monomers using a Ni(II) complex as a single catalyst for living/controlled polymerization. The crystallization‐driven self‐assembly of amphiphilic conjugated poly(1m‐b‐2n) led to the formation of nanofibers with controlled lengths and narrow dispersity. The block copolymers exhibited white, yellow, and red emissions in different self‐assembly states. By using uniform poly(1m‐b‐2n) nanofibers as seeds, introducing the polyfluorene‐block‐polythiophene‐block‐poly(phenyl isocyanide) triblock polymer as a unimer in the seed growth process, and adjusting the structure of the poly(phenyl isocyanide) block and the polarity of self‐assembly solvent, A−B−A triblock micelles, multiarm branched micelles, and raft micelles were prepared. [ABSTRACT FROM AUTHOR]

In this contribution we report on a novel approach towards luminescent light‐responsive ligands. To this end, cyanostilbene‐ guanidiniocarbonyl‐pyrrole hybrids were designed and investigated. Merging of a luminophore with a supramolecular bioactive ligand bears numerous advantages by overcoming the typical drawbacks of drug‐labelling, influencing the overall performance of the active species by attachment of a large luminophore. Here we were able to establish a simple and easily accessible synthesis route to different cyanostyryl‐guanidininiocarbonyl‐pyrrole (CGCP) derivatives. These compounds were investigated regarding their light‐responsive double bond isomerisation, their molecular structures in single crystals by means of X‐ray diffractometry, their emission properties by state of the art photophysical characterisation as well as bioimaging and assessment of cell toxicity. [ABSTRACT FROM AUTHOR]

Microemulsion based fuels (MBF) have gained significant attention in recent years due to their potential to enhance combustion efficiency, reduce emissions, and improve overall engine performance. This research paper enlightens the effects of physiochemical properties on the emission characteristics of CI engine. The microemulsions are formulated using surfactants, co‐surfactants, water or alcohols, and fuel components. The effects of density, viscosity, calorific value, cold flow properties, and cetane number along with the stability and the multi‐component characteristics of (MBF) has been taken into consideration to examine its effects on Emission characteristics such as nitrogen oxides (NOx), sulfur oxides (SOx), carbon monoxide (CO), particulate matter (PM), and unburned hydrocarbons (UHC). Microemulsion‐based fuels lower emissions of NOx and PM, recognized to the more complete combustion. The review highlights various studies that have investigated the benefits of microemulsion fuels, including reduced emissions of different pollutants and thus reduce the adverse effect on environment. In conclusion, microemulsion‐based fuels show likely physiochemical properties, as well as favorable emission characteristics, with reduced NOx, SOx, CO, PM, and UHC emissions. This study highlights the potential of microemulsion‐based fuels as environment friendly alternatives, flagging the way for further research. [ABSTRACT FROM AUTHOR]

The growing demand of sustainable and environment friendly energy sources has spurred research and development efforts towards the integration of biofuels in various applications, particularly in internal combustion engines. Microemulsion technique is a new and innovative alternative to traditional fossil fuel that has gained a significant attention in recent years. This type of bio fuel is made by blending of small amount of biofuel and large amount of conventional diesel fuel. This review paper explores the potential of enhancing the performance of Compression ignition (CI) engines by incorporating additives into hybrid biofuels. The study focuses on the synergistic effects of combining traditional fossil fuels with bio‐derived components, such as ethanol, biodiesel, and other bio‐based additives. This review paper aim is to explore the performance of a 4‐stroke, single‐cylinder, direct injection Compression Ignition (CI) engine at different loads using different fuels blends like CNWEDB, BFNP150, PPNP150, and ME Diesel/Colza oil. The review outlines recent advancements in biofuel technology, including novel production methods and feedstock options, aiming to overcome limitations associated with conventional biofuels. The article aims to investigate the potential of vegetable oil in formulating MHBF, analyzing its performance and emissions in CI engines. The engine performance parameters viz., brake thermal efficiency brake specific fuel consumption have been reviewed and found that these values are comparable to the biodiesel blends with pure petrodiesel. At 60%, 80%, and full load condition the BTE of microemulsion diesel/colza oil is increasing while at 40%, 80%, and full load the BSFC is decreasing. Emissions reported by the various researchers, however, have a positive attribute with respect to NOx, CO, and UHC. At full load CO is decreasing and at all load conditions the value of UHC is decreasing. The paper concludes with a discussion on future research directions, emphasizing the need for continued innovation to address emerging issues and optimize the performance of CI engines for a sustainable and energy‐efficient future. [ABSTRACT FROM AUTHOR]

ABSTRACT The present paper discusses the synthesis of unprecedented red‐emitting mono‐azo compound pyrazole azo fluorescent tag (PAFT) by a diazotization method, followed by an electrophilic substitution reaction. Further, the metal complex of PAFT is also prepared by refluxing the ethanolic solution of the ligand with the corresponding metal (RuCl3 and C4H6CuO4.H2O) salts under suitable experimental conditions. The synthesized fluorophore PAFT displays intense fluorescence in the aggregate state and has excellent qualities, including high purity, low cost, eco‐friendliness, and good photostability. These unique characteristics of PAFT led to the development of new fluorescence‐based technology for the in situ viewing of latent fingerprints. Various spectroscopic and analytical techniques are used to confirm the structural characteristics of the synthesized compounds, including UV–Vis, FT‐IR, (1H) NMR, HRMS, TGA, VSM, ESR, and powder XRD methods. The potency of the antibacterial activity of the compounds was evaluated. The results revealed that compound PAFT and [Ru(PAFT)Cl3] H2O showed excellent sensitivity at 0.8 μL/mL against the Gram‐positive bacteria Staphylococcus aureus. [ABSTRACT FROM AUTHOR]

2D van der Waals (vdW) layered materials exhibit significant exciton binding energy and versatile stacking options, making them ideal for room‐temperature exciton‐polariton devices used in low‐threshold lasing, nonlinear optical switching, and quantum computing. However, most existing systems depend on external optical microcavities coupled with single monolayers, leading to limited controllability and increased costs. Here, external cavity‐free vdW magnet CrSBr crystals are presented that feature magnetically controllable self‐hybridized exciton‐polaritons that remain stable up to room temperature. The ultrastrong exciton‐photon coupling suppresses donor‐, phonon‐, and defect‐related emissions. Furthermore, the exciton‐polariton dispersion and emission spectra can be effectively controlled by adjusting the magnetic field, temperature, and CrSBr thickness. This vdW exciton‐polariton material platform, demonstrating remarkable magnetic responsiveness in open cavity configurations under ambient conditions, paves the way for the development of compact, fast, and low‐loss spin, quantum, and magneto‐photonic devices. [ABSTRACT FROM AUTHOR]

Synthesis and characterization of two curcumin analogues BAA and Br‐AA via a condensation reaction was reported. Both the synthesized organic luminophores exhibited aggregation‐induced emission (AIE) with bright yellow and green emission respectively. Increase in the water% enhanced the emission by both the compounds confirmed the AIE property. A detailed study of latent fingerprints visualization was also carried out for both the analogues. Both the compounds showed good to normal capability to develop latent fingerprints (LFPs). Compound BAA performed better as a fluorescent material to develop LFPs compared to Br‐AA. The LFPs developed were analyzed to obtain 1–3 level of fingerprint patterns under UV 365 nm illumination. The LFPs developed using BAA exhibited excellent efficiency, sensitivity, high contrast with low background interreference. All three levels of fingerprint patterns were identified by BAA. However, Br‐AA showed inability to develop high clarity images of latent fingerprints. The solid‐state emission nature of the analogues was also evaluated from their emission spectra and CIE coordinates were found to be were (0,187, 0.518) and (0.265, 0.484) for BAA and Br‐AA respectively. [ABSTRACT FROM AUTHOR]

Small organic molecules absorbing and emitting in the shortwave infrared (SWIR, 1000–2000 nm) region are desirable for biological imaging applications due to low auto‐fluorescence, reduce photon scattering, and good tissue penetration depth of photons which allows for in vivo imaging with high resolution and sensitivity. Si‐substituted xanthene‐based fluorophores with indolizine donors have demonstrated some of the longest wavelengths of absorption and emission from organic dyes. This work seeks to compare an indolizine heterocyclic nitrogen with dimethyl aniline nitrogen donors on otherwise identical Si‐substituted xanthene fluorophores via optical spectroscopy, computational chemistry and electrochemistry. Three donors are compared including an indolizine donor, a ubiquitous dimethyl aniline donor, and a vinyl dimethyl aniline group that keeps the number of π‐bonds consistent with indolizine. Significantly higher quantum yields and molar absorptivity are observed in these studies for a dimethylamine‐based donor relative to a simple indolizine donor absorbing and emitting at similar wavelengths (~1312 nm emission). Substantially longer wavelengths are obtainable by appending aniline‐based groups to the indolizine donor (~1700 nm) indicating longer wavelengths can be accessed with indolizine donors while stronger emitters can be accessed with anilines in place of indolizine. [ABSTRACT FROM AUTHOR]

Sequence‐independent detection of low concentrations of nucleic acids is important for applications in forensics and diagnostics. An emission‐based probe for detecting and quantifying DNA and RNA utilizing a water‐soluble dicationic tetraphenylethene (TPE) derivativewas developed. The recognition is based on the electrostatic and other non‐covalent interactions between the phosphate backbone of nucleic acids and the cationic probe, which cause the restriction of rotation of the aryl units of the probe, ensuing in the enhancement of the fluorescence signal. The binding was validated by different spectroscopic techniques and also by electrophoretic mobility shift assay. The probable mode of binding with the nucleic acids was studied by blind‐docking studies that correlated well with the experimental results. [ABSTRACT FROM AUTHOR]

In developing countries, electrical power distribution networks are often inadequate, particularly in small health centers. As a result, the electrical energy supplied by the grid is frequently interrupted. The productivity and quality of service delivered by these health centers to the people who live in these areas are severely affected by this issue. This issue can be resolved by incorporating battery storage systems along with renewable energy sources into the distribution system. The direct delivery of energy to customers is greatly aided by these renewable energy supplies. Partially, the grid supports such a system on a limited scale to guarantee the continuity of the energy supply. This study tried to resolve the problem due to these frequent power outages and its economic expenditures. To address the illustrated challenges, we tried to renovate the diesel generator with a solar and battery energy supply. The PVsyst software shows the average global solar radiation in the selected zone is5.84kmh/m2/day$$ 5.84\ \mathrm{kmh}/{\mathrm{m}}^2/\mathrm{day} $$. The annual energy demand for Gedeo health centers in 2023 is 3.32 MWH and the proposed PV‐battery hybrid system has a 10.95 MWH capacity. Moreover, when we utilize a diesel generator the Capital cost (CC), Net present cost (NPC), levelized cost of energy (LCOE), and payback period are 12 452.25$, 13 369.12$, 0.1$, and 10.7 years respectively. The economic assessment result of the proposed system is 4083$, 4727$, 0.059$, and 3.8 years consecutively. In southern Ethiopia, the annual emission from diesel generators alone, excluding the emission from the vehicles is close to 692 tons. Consequently, from the empirical economic assessment the installed solar energy is 90% more beneficial than the existing system. [ABSTRACT FROM AUTHOR]

Streams are important sources of methane (CH4) to the atmosphere but magnitudes and regulation of stream CH4 fluxes remain uncertain. Stream CH4 can come from groundwater and/or produced in anoxic sediments. A fraction can be microbially oxidized to carbon dioxide (CO2) when passing redox gradients in soil, sediment, or water, while the fraction escaping oxidation is emitted to the atmosphere. The relative importance of the CH4 sources (groundwater inputs vs. sediment production) and the fraction oxidized is typically unknown, yet key for the regulation and magnitude of stream emissions. In this study, we followed the transport of CH4 from below‐stream soils to the stream water surface and to the atmosphere using a combination of CH4 concentration and stable carbon isotope gradient measurements, high resolution stream flux and discharge assessments, and inverse mass‐balance modeling. Sampling was done in multiple locations in the stream network of two independent catchments in Sweden to consider spatial variability. We show that the surface water, sub‐surface, and groundwater CH4 concentration, CH4 oxidation, and emission were highly variable in space. Our results indicate that the variability could be related to stream morphology and soil characteristics. Of the total CH4 input into the streams, roughly half of it was estimated to come from groundwater CH4 in both catchments (39% and 57%; the rest from sediment production), and most of the CH4 was oxidized (97%–99%) before emission to the atmosphere. Our results indicate that CH4 oxidation is a major sink for CH4 in the studied streams. Plain Language Summary: Streams emit a large amount of the greenhouse gas methane to the atmosphere. Sources of this methane can be groundwater and/or production in stream sediments. A part of the methane can be oxidized by microbes into carbon dioxide and the rest can evade to the atmosphere as methane. The relative magnitudes of the sources, oxidation, and emission are usually unknown but important for understanding the regulation of stream methane emissions. In this study in two stream networks of Sweden, inverse mass‐balance modeling was done using multiple measurements and we show that the sources of methane, its oxidation and emission were highly variable in space. About half of the methane in the streams was contributed by groundwater and the rest was estimated to be produced in the sediments. Most of the methane was oxidized in the streams and only a small fraction escaped to the atmosphere. Key Points: Large spatial variability in CH4 concentration, net inputs, oxidation and emission was observedRoughly half of the CH4 inputs in the streams were contributed by groundwater and the rest by sediment productionMost of the total potential stream CH4 input was oxidized before reaching the atmosphere [ABSTRACT FROM AUTHOR]

Dichlorodifluoromethane (CFC‐12) is an ozone‐depleting substance and potent greenhouse gas, which was required to be phased out after 2010 under the Montreal Protocol. CFC‐12 emissions need to be quantitatively traced. However, estimates of CFC‐12 emissions in China based on atmospheric inversions are unavailable after 2010. Here, using atmospheric observations at nine sites across China and inversion techniques, we quantify CFC‐12 emissions in China during 2011–2020 (on average 11.0 ± 0.6 Gg yr−1). The emissions derived from observations are 8.5 times larger than the previously reported inventories. Apart from emissions from eastern China revealed in previous studies, this study reveals that 71% of national total emissions were from other parts of China. Moreover, this study reconciled the global CFC‐12 emissions during 2011–2020: 28% were traced to China by this study, 9% of emissions were traced in previous studies, while 63% remain untraced, indicating the need for more regional emission inversion studies. Plain Language Summary: Chlorofluorocarbons (CFCs), well known as Freon, are damaging to the stratospheric ozone layer and are potent greenhouse gases. Dichlorodifluoromethane (CFC‐12; CCl2F2) is one of the major CFCs. The production and consumption of CFC‐12 are controlled under the regulations of the Montreal Protocol and have been phased out globally since 2010. As the largest developing country and once a major producer and consumer of CFC‐12, CFC‐12 emissions in China are of great interest. In this study, we quantified emissions of CFC‐12 in China during 2011–2020 based on atmospheric observations in a network of nine sites across China. We find that the emissions derived from atmospheric inversion are 8.5 times larger than the previous emission inventories estimated using production and consumption information, suggesting unaccounted‐for emissions occurring in China. Apart from emissions from eastern China revealed in previous studies, this study reveals that 71% of national total emissions were from other parts of China. The Chinese emissions of CFC‐12 accounted for 28% of global totals from 2011 to 2020. However, there is a big gap between the total CFC‐12 emission from China, western Europe, Australia, the United States, India, and global totals, suggesting that more regional atmospheric inversion estimates are encouraged. Key Points: China's Dichlorodifluoromethane (CFC‐12) emissions during 2011–2020 were quantified using atmospheric observations at nine sites across China and inverse modelingA quantitative depiction of spatial CFC‐12 emissions across China was provided by this study28% of global CFC‐12 emissions for 2011–2020 occurred in China, according to this study [ABSTRACT FROM AUTHOR]

The application of transition metal complexes for antimicrobial photodynamic therapy (PDT) has emerged as an attractive alternative in mitigating a broad range of bacterial pathogens, including multidrug‐resistant pathogens. In view of their photostability, long excited‐state lifetimes, and tunable emission properties, transition metal complexes also contribute as bioimaging agents. In the present work, we designed mono and trinuclear cyclometalated iridium (III) complexes to explore their imaging application and antibacterial potential. For this, we used Methicillin‐resistant S. aureus (MRSA), the most prevalent of community‐associated (CA) multidrug‐resistant (MDR) bacteria (CA MDR) and Lactococcus lactis (L. lactis) as Gram‐positive while Campylobacter jejuni (C. jejuni) and E. coli as Gram‐negative bacteria. In addition to differential bioimaging of these bacteria, we assessed the antibacterial effects of both mono and trinuclear Ir(III) complexes under exposure to 427 nm LED light. The data presented herein strongly suggest better efficacy of trinuclear Ir(III) complex over the mononuclear complex in imparting photoinduced cell death of MRSA. Based on the safety profile of these complexes, we propose that trinuclear cyclometalated iridium(III) complex holds great promise for selective recognition and targeting MDR bacteria with minimal off‐target effect. [ABSTRACT FROM AUTHOR]

To develop new hybrid micelles with alkyl/polyaromatic core–shell structures, we synthesized umbrella‐shaped amphiphiles bearing a bent anthracene dimer with a linear alkyl chain (i.e. octyl and hexadecyl groups). The amphiphiles quantitatively assemble into spherical micelles (~2–3 nm in core diameter), possessing an alkylated cavity surrounded by a polyaromatic framework, in water. The alkylation significantly enhances the stability of the micellar structures against dilution (up to 9 μM) and heat (up to >120 °C). The highly condensed hexadecyl core of the hybrid micelle, as indicated by solvatochromic guest probes, displays increased uptake ability toward large alkylated metallodyes. Interestingly, efficient uptake of aromatic macrocycles (i.e. [n]cycloparaphenylenes) by the present micelle provides pseudorotaxane‐shaped host–guest composites with high emissivity (ΦF=up to 35 %). Internal multi‐alkylation of an aromatic micelle can thus successfully enhance its assembly stability/guest uptake functions. [ABSTRACT FROM AUTHOR]

We present a comprehensive study of the nightside aurora phenomenon on Mars, utilizing observations from EMUS onboard Emirates Mars Mission. The oxygen emission at 130.4 nm is by far the brightest FUV auroral emission line observed at Mars. Our statistical analysis reveals geographic, solar zenith angle, local time, and seasonal dependencies of auroral occurrence. Higher occurrence of aurora is observed in regions of open magnetic topology, where crustal magnetic fields are either very weak or both strong and vertical. Aurora occurs more frequently closer to the terminator and is more likely on the dusk side than on the dawn side of the night hemisphere. A pronounced auroral feature appears close to midnight local times in the southern hemisphere, consistent with the spot of energetic electron fluxes previously identified in the Mars Global Surveyor data. This auroral spot is more frequent after midnight than before. Additionally, some regions on Mars are "aurora voids" where essentially no aurora occurs. Aurora exhibits a seasonal dependence, with a major enhancement near perihelion. Non–crustal field aurora additionally shows a secondary enhancement near Ls 30°. This seasonal variability is a combination of the variability in ionospheric photoelectrons and thermospheric atomic oxygen abundance. Auroral occurrence also shows an increase with the rise of Solar Cycle 25. The brightest auroral pixels are observed during space weather events such as Coronal Mass Ejections and Stream Interaction Regions. These observations not only shed light on where and when Martian aurora occurs, but also add to our understanding of Mars' magnetic environment and its interaction with the heliosphere. Plain Language Summary: In this study, we explore the phenomenon of aurora on the nightside of Mars, using observations from the highly sensitive Emirates Mars Ultraviolet Spectrometer (EMUS) on the Emirates Mars Mission. Our analysis reveals distinct patterns in auroral occurrence on the planet. For instance, there is a higher rate of auroral activity in regions where Mars' magnetic field lines are open (i.e., connected to the collisional atmosphere at one end). We also found that aurora is more common near the terminator (with the occurrence decreasing as the solar zenith angle increases), and particularly during the evening hours, as opposed to early morning. Interestingly, these auroral events also show a seasonal dependence, peaking around perihelion in a Martian year, when Mars is closest to the sun. This seasonal pattern corresponds with the variation of photoelectrons in Mars' dayside ionosphere and the atomic oxygen abundance in the thermosphere. Auroral occurrence increases with increasing solar activity. Also, the auroral brightness increases during space weather events. Our study not only gives us a clearer picture of where and when the aurora occurs on Mars but also hints at the underlying processes influencing them, offering insights into the planet's magnetic and charged particle environment. Key Points: Higher auroral occurrence is observed in regions of open magnetic topology, where crustal fields are either very weak or primarily verticalAurora occurs more frequently near the terminator compared to deep night, with higher occurrence at dusk than at dawnAurora occurs more frequently near perihelion, with the brightest auroral pixels observed during space weather events [ABSTRACT FROM AUTHOR]

The current investigation uses biodiesel extracted from Moringa oleifera seeds in a diesel engine. M. oleifera biodiesel is prepared via conventional transesterification with standard conditions (60°C reaction temperature, 120 min reaction time, 1% by wt. catalyst, and 7.5:1 molar ratio). The test engine is a single‐cylinder air‐cooled naturally aspirated direct injection diesel engine. The test engine for experimentation is operated at 100% load with different engine speeds ranging from 1000 to 2400 rpm. Emissions characteristics were analyzed at different engine speeds. Results were interesting as the MB10 blend (10% M. oleifera biodiesel + 90% diesel) lowered the smoke by 24% and hydrocarbon by 10.34% with respect to neat diesel. Almost all the test fuels have higher HC profiles at reduced engine speeds. The MB20 blend lowered the CO profile to the CO profile of diesel fuel by about 0.84%. However, it can be observed that the MB10 blend's average CO profile is improved by 1.97% than mineral diesel. These results are compromised with higher CO and NOx profiles of 2.4% and 8.9%, respectively. [ABSTRACT FROM AUTHOR]

The impact of growth in the overall population is imposed on the continuous degradation process for environmental wastes like agricultural, industrial, food products, farming waste, etc. The improper degradation may lead to pollution and toxicity for ecological living. Based on waste management concepts, environmental wastes are reduced, reused, and recycled against environmental pollution. Most environmental wastes are recycled and used as biofuel for various energy sectors like alternative fuels. Globally, vegetable loss or wastage increased by more than 35% due to the level of retailers and consumers. The present study attempts to produce a low‐cost, reliable, environmentally emission‐free biofuel using waste vegetable resources via pyrolysis reactor arrangements. The synthesized bio‐fuel energy implemented for compression ignition engine and its performance was evaluated by single cylinder four stroke diesel engine and found higher brake power and thermal efficiency of 6.89 kW and 50.29%. Finally, the emission characteristics are assessed by an exhaust gas emission tester. CO and HC emissions showed minimum amounts like 0.021% and 47 ppm. [ABSTRACT FROM AUTHOR]

Fuels consisting of high hydrogen concentration can be consumed under colourless distributed combustion (CDC) to suppress flashback tendency in premixed conditions. Higher NOX challenges can also be overcome through CDC. For those purposes, coke oven gas was consumed under CDC within the scope of this study. To achieve CDC, N2 or CO2 diluents were introduced into the oxidizer so that oxygen concentration in the oxidizer would be decreased from 21% O2 to its lean blow‐off limits. Excess air ratios were determined as λ = 1.2 and λ = 1.5 along with a thermal power of 10 kW under premixed conditions. A commercial computational fluid dynamics code was used to predict temperature distribution and NOX, CO, and CO2 emissions. 162‐step reactions created with GRI‐Mech 3.0 chemical kinetics was integrated to the eddy dissipation concept combustion model. The temperature and NOX profiles predicted were compared with the experimental results. Consistency was achieved at ~95% for temperature profiles, and almost 100% for NOX profiles between the measured and the predicted ones. According to the results, it is concluded that a more homogeneous temperature distribution with the ~21% decrease in the maximum temperature was observed, and there was about 96% decrease in NOX level. It was also demonstrated that using CO2 as a diluent is more effective in terms of temperature distribution over the combustor and NOX reduction, while dilution with N2 is more effective in terms about 70% in decrease on CO. [ABSTRACT FROM AUTHOR]

The present study tested newly formulated hydrous ethanol–diesel‐emulsified fuel infused with nano‐sized γ‐Al2O3 particles on a turbocharged CRDI 4‐cylinder stationary diesel engine. W5H5, W5H10, and W10H5 test fuels were inducted into engine cylinders at a fixed engine speed of 2000 rpm. These test fuels significantly improved their physicochemical properties, with an 8.80% increase in gross calorific value and a 6.52% growth in cetane index. W5H10 exhibited a 16.01% increment in brake thermal efficiency and a 22.22% decrement in brake‐specific fuel consumption. Also, this fuel reported an 8.64% higher in‐cylinder pressure and a 40.71% higher heat release rate. W5H10 test fuel noted a 50% dip in carbon monoxide emissions and an 84.56% lower smoke opacity than diesel. W5H5 fuel reported 33.33% lower unburnt hydrocarbons than diesel at full load. W10H5 fuel observed an 88.46% drop in nitrogen oxide emissions compared with diesel at 10% engine load. The author found W5H10 the most suitable fuel for diesel engines with no modification costs. [ABSTRACT FROM AUTHOR]

Nanoparticles are now widely used in biodiesel‐diesel combinations for improving the engine performance and reduction of emissions. This present study investigates the Bio‐silica (Silicon‐dioxide, SiO2). The statistical and experimental study demonstrates the utilization of various levels of SiO2 in Azolla Biodiesel blend (ABD) with appropriate engine parameters such as fuel injection pressure, fuel injection timing and compression ratio for minimal emissions and optimal performance employing response surface approach. In a mixture of Azolla biodiesel and diesel, SiO2 nanoparticles were utilized at quantities of 25, 50, and 75 ppm. To determine the existence of Silicon‐dioxide, the produced nanoparticles were subjected to tests such as XRD, SEM, TEM, and EDS. The Response Surface optimizer was used with DOE L29 array and the engine predictors with a desirability value of 0.6180, were18.5°bTDC (IT), 238 Bar (IP), 17.1237 (CR), and 45.885 ppm SiO2 nanoparticle. The results were determined to be fit statistically and with high assurance levels. Thus, the addition of SiO2 nanoadditives along with aquatic fern Azolla oil methyl ester reduced the emission without affecting the engine performance. [ABSTRACT FROM AUTHOR]

Doping has been proven to be a good way to regulate the optical and electrical properties of the active elements including both inorganic and organic materials. In this paper, the study demonstrates a bipolar doping strategy for an intrinsic charge‐transfer binary‐complex through the use of p‐ and n‐type dopants, which incorporate toward highly‐ordered ternary complexes. Benefitting from the good lattice matching and energy level tuning, the supramolecular system with a large doping concentration range (0 ≤ x ≤ 50% or 40%) assembles into the original crystal lattice and exhibits tunable luminescence or quenching phenomena even at very low ratio. The 7h‐benzo[c]carbazole (BCZ) dopped cocrystals show yellow–green to red emission due to the Förster resonance energy transfer (FRET); while only 5% 7,7,8,8‐tetracyanoquinodimethane (TCNQ) dopant can bring superior photothermal (PT) behavior with a high PT conversion efficiency up to 75.3%, owing to the efficient non‐radiative decay way contribution. It is believed that the strong π–π interactions and free rotation of −C(C≡N)2 promote this decay way transition. This work on the charge‐transfer complex doping system suggests the great potential in optical, photothermal imaging, and therapy applications as well as information memory and photo sensing. [ABSTRACT FROM AUTHOR]

The pathogen‐based diseases are prime concern for modern society. Some oxide‐based nanomaterials have been found to show promising antimicrobial activities. However, the industrial synthesis of these oxide materials are harmful to environment. Zinc oxide nano‐flakes were prepared using corn silk (Zea mays) extract. The material was characterized by spectral and microscopic techniques. XRD data shows rutile structure and nano‐crystal size of 36.15 nm. SEM indicates morphology consisting of nano size particles with porous structure. EDX confirms presence of Zn and O. UV‐Vis data shows band gap of 3.62 eV. On excitation, PL exhibits a variety of emission bands in visible spectrum. Dielectric properties suggest the dielectric constant has a well‐dispersed real and imaginary portion. The ZnO NFs were subjected to antimicrobial activities (in dark and under white light) against various strains like E. coli, K. pneumonia and S. aureus. The light induced antibacterial activity is slightly higher as compared to that in dark. Best part of this study is that minimum concentration of ZnO can be used in presence of light thereby reducing the toxicity to the environment due to these metal oxides. Based on the observed results, this material could be used as multi‐dimensional functional material in day‐to‐day life. [ABSTRACT FROM AUTHOR]

Wildfires are increasing across the USA. While smoke events affect human exposure and air quality, wildfire smoke effects on ecosystem‐atmosphere interactions are poorly understood. We investigate smoke effects on biogenic volatile organic compound (VOC) emissions and photosynthesis for ponderosa pines. During several wildfire smoke events, we observed photosynthetic reduction with evidence for stomatal plugging and changes in leaf‐level uptake and emission of both biogenic and wildfire VOCs. During intense smoke events, photosynthesis and VOC emissions were almost entirely suppressed, but increased dramatically upon stomatal opening. We propose four types of VOC responses to this burst in stomatal opening: post‐burst emissions, pulsed emissions, surge emissions, and post‐burst uptake. Our observations suggest that wildfire smoke can affect plant physiology and leaf‐atmosphere gas exchange. Plain Language Summary: Wildfires are becoming more prevalent in the United States. Wildfire smoke affects human health and air quality, but we know little about how smoke interacts with plants, or the subsequent feedback with the atmosphere. We present results from a field experiment during which smoke repeatedly spread across a pine forest. We measured smoke‐induced changes in plant physiology (namely photosynthesis) and a suite of chemical emissions. During prolonged periods of intense smoke, we found that both photosynthesis and leaf emissions of chemical compounds decreased. When we induced photosynthesis, we observed a burst of different chemicals and identified several different pathways for these chemical releases. Further analyses suggest that smoke intensity and exposure may change the known relationship between emissions and temperature. Key Points: Wildfire smoke interacts with stomates and leaf surfaces, suppressing photosynthesis and stomatal conductanceIntense smoke can alter emissions and uptake of biogenic and other volatile organic compounds through three mechanismsThe effects of wildfires on photosynthetic capacity and leaf emissions appear proportional to the intensity and duration of smoke events [ABSTRACT FROM AUTHOR]

Perylene diimides (PDIs) have received considerable attention as a versatile class of functional dyes owing to their flexible reaction sites and remarkable stability. Recent advances have enhanced our understanding of the fluorescence and photothermal conversion properties of PDI molecules. The interplay between radiative and nonradiative transitions controls the emission and heat generation processes in these molecules. This comprehensive overview summarizes the recent strategies for manipulating the structures of PDI molecules for fluorescence and photothermal conversion applications. Additionally, challenges and potential solutions associated with the usage of fluorescent and photothermal PDI molecules are discussed. [ABSTRACT FROM AUTHOR]

We, herein, report a facile green synthetic route for the gram‐scale synthesis of high‐quality thiol‐derivatized zinc selenide quantum dots (QDs) using selenourea as the source of selenium at a relatively low temperature. The one‐pot synthesis of colloidal dots has been achieved by selenizing zinc (II) acetate in a non‐coordinating solvent medium. The structural, microstructural, optical, thermal, textural and electronic properties of the as‐synthesized monodisperse ZnSe dots have been investigated in detail. We attribute the observed green emission from the dots to the donor‐acceptor pair (DAP) recombination of photoexcited charge carriers. All the findings of the investigation indicate that ZnSe QDs hold great promise as a nanoscale emissive probe to unveil cellular dynamics beyond the capabilities of conventional imaging techniques. [ABSTRACT FROM AUTHOR]

Summary: This paper introduces grasshopper optimization algorithm to efficiently prove its superiority in the optimal power flow problem. To demonstrate the efficiency of the proposed algorithm, it is implemented on the standard IEEE 30‐bus, IEEE 57‐bus, and IEEE 118‐bus test systems with different objectives that reveal presentation indices of the power system. Twelve different cases, in single and multi‐objective optimization space, are considered on different curves of fuel cost, environmental pollution emission, voltage profile, and active power loss. The simulation results obtained from grasshopper optimization algorithm techniques are compared to other new evolutionary optimization methods surfaced in the current state‐of‐the‐art literature. It is revealed that the proposed approach secures better consequence over the other newly originated popular optimization techniques and reflects its improved quality solutions and faster convergence speed. The results obtained in this work demonstrate that the grasshopper optimization algorithm method can successfully be applied to solve the non‐linear problems connected to power systems. [ABSTRACT FROM AUTHOR]

Mars discrete aurorae are caused by accelerated electrons precipitating into the atmosphere and interacting with species such as atomic oxygen. However, the energy of the electrons causing these aurorae remains currently unclear: no simultaneous and concurrent measurements of electron analyzers and spectrometers have been performed so far, preventing from assessing the exact energy of the downgoing auroral electrons. Several auroral emissions have been observed so far on Mars, among which are two oxygen emissions in the far ultraviolet at 130.4 and 135.6 nm. In this study, we simulate the vertical distribution of these auroral oxygen emissions with an electron transport calculation coupled with a radiative transfer model to account for the optical thickness of the atmosphere for the 130.4‐nm triplet. We show that the brightness ratio of these oxygen emissions is independent of the downward electron energy flux and only slightly depends on the atomic oxygen atmospheric composition. In contrast, the brightness ratio is strongly related to the initial energy of the auroral electrons. Measuring the brightness ratio is therefore a unique tool to remotely estimate the energy of the electrons causing the Mars discrete aurorae. We compare our model results with observations from the Emirates Mars Ultraviolet Spectrometer on board the Emirates Mars Mission and find that electrons with typical energies of 250–300 eV are compatible with the observed ratio of 5. Plain Language Summary: Aurorae have been observed on the nightside of Mars. They are caused by energetic electrons that interact with the constituents of the Mars atmosphere. However, since no direct measurement has been performed during auroral events, the energy of these auroral electrons remains currently unclear. In this study, we simulate the brightnesses of two auroral emissions of atomic oxygen in the far ultraviolet as if they were seen from an orbiter. We use a photochemical model as well as an electron transport model and a radiative transfer model. We demonstrate that the brightness of these emissions strongly depends on the initial energy of the auroral electrons and their flux. In contrast, the ratio of the brightness of the emissions is independent on the flux and therefore represents a unique tool to remotely estimate the energy of the electrons causing the Mars discrete aurorae. We compare our model results with observations from the Emirates Mars Ultraviolet Spectrometer on board the Emirates Mars Mission and find that electrons with energies of 250–300 eV are responsible for the observed ratio of 5. Key Points: The 130.4 optically thick and the 135.6 nm optically thin oxygen emissions can be observed during a Mars auroral eventRadiative transfer effects increase the observed nadir brightness of the 130.4‐nm emissionBrightnesses of both emissions depends on O density, initial electron energy and flux, while their ratio depends on the electron energy [ABSTRACT FROM AUTHOR]

In this study, the melt quenching approach is used to synthesize a lead borate–strontium‐based glass system doped with samarium ions. Modifications in the glass network structure arising from the addition of various concentrations of Sm3+ ions were investigated via Fourier transform infrared (FTIR) spectroscopy. FTIR analysis revealed B–O–B bridges, BO3, and BO4 units are present. UV–vis–NIR spectroscopic measurement was performed to study the optical absorption spectra. Optical constants such as optical bandgap energies, refractive indices, and other related parameters were evaluated. The lifetime fluorescence decay was measured and ranged between 1.04 and 1.88 ns. The photoluminescence spectra in the range 500–750 nm revealed four transitions from the ground state 6G5/2 to the excited states 6H5/2, 6H7/2, 6H9/2 and 6H11/2 and J–O theory was utilized to study these optical transitions for Sm3+ ions. Calculations of the oscillator strengths and J–O intensity parameters were performed and the obtained J–O parameters followed the sequence Ω4 > Ω6 > Ω2. The ratio O/R indicated a high lattice asymmetry around the samarium ions. The values of lifetimes and branching ratios for the fabricated samples emphasized their suitability to be used in laser applications. The current glass samples are good candidates for orange and red emission devices. [ABSTRACT FROM AUTHOR]

We present the first observations of the dayside coronal oxygen emission in far ultraviolet (FUV) measured by the Emirates Mars Ultraviolet Spectrometer (EMUS) onboard the Emirates Mars Mission (EMM). The high sensitivity of EMUS is providing an opportunity to observe the tenuous oxygen corona in FUV, which is otherwise difficult to observe. Oxygen resonance fluorescence emission at 130.4 nm provides a measurement of the upper atmospheric and exospheric oxygen. More than 500 oxygen corona profiles are constructed using the long–exposure time cross–exospheric mode (OS4) of EMUS observations. These profiles range from ∼200 km altitude up to several Mars radii (>6 RM) across all seasons and for two Mars years. Our analysis shows that OI 130.4 nm is highly correlated with solar irradiance (solar photoionizing and 130.4 nm illuminating irradiances) as well as changes in the Sun–Mars distance. The prominent short term periodicity in oxygen corona brightness is consistent with the solar rotation period (quasi–27–day). A comparison between the perihelion seasons of Mars Year (MY) 36 and MY 37 shows interannual variability with enhanced emission intensities during MY 37, due to the rise of Solar Cycle 25. These observations show a highly variable oxygen corona, which has significant implications on constraining the photochemical escape of atomic oxygen from Mars. Plain Language Summary: The highly sensitive Emirates Mars Ultraviolet Spectrometer (EMUS) onboard Emirates Mars Mission (EMM) is capable of observing ultraviolet emissions emanating from Mars. Oxygen in the Martian exosphere is hard to see because it's tenuous. In this study, the analysis of long exposure time EMUS optical observations show that the hot oxygen corona on Mars has a short term variability due to solar rotation. Hot oxygen corona also shows a long–term variability that depends on the Sun–Mars distance and the solar cycle progression. When comparing data from two Martian years, it is noticed that the oxygen corona became brighter when the Sun is more active. Key Points: Brighter O corona is observed during perihelion and dimmer during aphelion, indicating a strong relationship with the Sun‐Mars distanceThe variation in OI 130.4 nm brightness shows a linear correlation with solar EUV irradiance, with a short‐term solar rotation periodicityInterannual variability is observed from MY 36 to MY 37, showing an enhancement in O corona brightness with the rise of Solar Cycle 25 [ABSTRACT FROM AUTHOR]

The green hub‐and‐spoke airline network (GHSAN) is emerging as a dominant feature due to its excellent economic and environmental‐friendly capabilities. However, environmental GHSAN designs still have some concerns, including single pollutant‐domain oversimplification and lack of comprehensive network‐level operation impacts. This paper proposes a multi‐emission‐driven efficient network design approach for GHSAN, utilizing a system, green, and user threefold optimization methodology. The approach includes a multi‐objective optimization model and a two‐layer solving method. The multi‐objective optimization aims at minimizing multiple emissions, including carbon dioxide, carbonic oxide hydrocarbon, and nitric oxide, while also considering transportation system costs and journey user costs. A two‐layer optimization algorithm is adopted to address different scales of optimization. Real‐world results demonstrate that the proposed method mitigates environmental impact and user costs and increases overall airline density in airline networks. The proposed method can have a 16.29% reduction in green‐fold (10 nodes) and a 12.06% decrease in user costs for the user‐fold (10 nodes). As the number of nodes (15, 25, 50 nodes) and hubs (3, 4, 5, 6, 7 hubs) increase, the genetic algorithm (GA) proves to be more efficient and suitable in large‐scale GHSAN. This work is further significant for the long‐term and sustainable development of the future air transport industry. [ABSTRACT FROM AUTHOR]

As the next generation of display technology, Mini Light‐Emitting Diodes (LEDs) have attracted much attention, among which the phosphor used as the backlight should meet the characteristics of small particle size and high brightness. A series of Ba1.2Ca0.7‐xSiO4:0.1Eu2+, xMn2+ are synthesized by the coprecipitation‐solid state method. Hence, the prepared phosphor has a submicron structure with an average particle size of 1.3 ± 0.9 µm. It can be excited by 365–410 nm, with an emission peak of 616 nm and a half‐peak width of 65 nm. At 150 °C, it exhibits a 94% emission intensity and good thermal stability. From 15% to 29%, the external quantum efficiency (EQE) increases. Therefore, the phosphors are suitable for Mini LED displays with near‐ultraviolet light as the excitation source. This method provides a new idea for the development of novel small particle sizes and narrow‐band emission phosphors. [ABSTRACT FROM AUTHOR]

Modified silver nanoparticles with a self‐assembled disulfide functionalized 2,2'‐bipyridine (L1 and L2) monolayer, and the corresponding rhenium complex [Re(L2)(CO)3Br] are shown to provide a method to position the nanoparticles at a water/dichloromethane interface forming a lustrous metal‐like‐liquid film (MeLLF) with a unique SERS response. The film formed using L2 showed divergent behaviour in the presence of a range of metal ions whilst bound to the surface. [Re(L)(CO)3Br] (where L=2,2'‐bipyridine, L1 and L2) in solution demonstrates a selective interaction with Hg2+, observed by UV‐vis, emission and 1H NMR spectroscopy, attributed to abstraction of the bromide. This interaction was demonstrated by subtle changes in the characteristic Raman Re‐CO stretch at 510 cm−1 both with the MeLLF, and when the film is immobilized in a PVA surface‐exposed‐nano‐sheet (SENS). The work provides proof of concept that the organometallic complexes can be employed as "labels" to generate SERS‐active nanoparticle films that possess detection capabilities. [ABSTRACT FROM AUTHOR]

The shift in consumer behaviour from in‐person to online shopping has led to an increase in parcel delivery volume and its associated negative impacts, such as CO2 emissions in cities. With the emergence of drone‐delivery technologies, the authors analyzed a joint delivery method using drones and trucks, which is an emerging alternative solution for last‐mile delivery in terms of CO2 emissions and delivery time. The analysis verified the highest possible level of reduction in CO2 emissions for the simultaneous and strategic operation of drones and trucks compared to diesel‐ or electric‐only truck operations. Moreover, this approach leads to reduced delivery times. A sensitivity analysis was performed to optimize the delivery‐drone flight performance in a drone‐and‐truck delivery strategy. It was found that a 1.5‐km drone flight performance was sufficient when considering the reasonable assumptions adopted in this study. Furthermore, based on the analysis results, drone‐and‐truck cooperative delivery strategies may not provide a significant advantage in terms of CO2 emissions compared with alternative transportation modes, such as fuel‐cell trucks with sufficiently low emissions. It has been empirically verified that changes in CO2 emissions are proportional to the number of clusters. However, there is a risk of local optima due to microscopic fluctuations among neighbouring cluster numbers, which occurs during the search for the optimal number of clusters. [ABSTRACT FROM AUTHOR]

Red and green rare‐earth ion (RE3+) (RE = Eu, Tb):MgLa2V2O9 micro‐powder phosphors were produced utilizing a standard solid‐state chemical process. The X‐ray diffraction examination performed on the phosphors showed that they were crystalline and had a monoclinic structure. The particles grouped together, as shown in the scanning electron microscopy (SEM) images. Powder phosphors were examined using a variety of spectroscopic techniques, including photoluminescence (PL), Fourier‐transform infrared, and energy dispersive X‐ray spectroscopy. Brilliant red emission at 615 nm (5D0 → 7F2) having an excitation wavelength (λexci) of 396 nm (7F0 → 5L6) and green emission at 545 nm (5D4 → 7F5) having an λexci = 316 nm (5D4 → 7F2) have both been seen in the emission spectra of Tb3+:MgLa2V2O9 nano‐phosphors. The emission mechanism that is raised in Eu3+:MgLa2V2O9 and Tb3+:MgLa2V2O9 powder phosphors has been explained in an energy level diagram. [ABSTRACT FROM AUTHOR]

Observations from the Michelson Interferometer for Global High‐Resolution Thermospheric Imaging onboard the Ionospheric Connection Explorer spacecraft are used to study the response of OI630.0 and OI557.7 nm dayglow to a moderate geomagnetic storm on 27 August 2021. The storm reaches a minimum Dst index of −82 nT, significantly impacting the dayglow within the latitudinal range of approximately 20°N–42°N, where the dayglow observations are of good quality. During the geomagnetic storm, the OI630.0 dayglow intensity slightly increases, while the peak volume emission rate (VER) decreases, and the peak height rises noticeably. The F‐layer intensity, peak VER, and the entire‐layer intensity of OI557.7 dayglow decrease significantly. The rise in peak height is not noticeable for the OI557.7 dayglow. The VERs of the both dayglow emissions respond differently to the geomagnetic storm at different altitudes. The OI630.0 dayglow layer as a whole extends upward and rises in altitude. For dayglow averaged above 35°N, the OI630.0 dayglow VER increases above approximately 225 km but decreases below this altitude. The largest increase occurs near 300 km, reaching approximately 82.8%, while the largest decrease occurs around 160 km, reaching about −22.0%. The OI630.0 dayglow intensity increases by approximately 6.3%, the peak VER decreases by about −8.0%, and the peak height rises by approximately 16.3 km, corresponding to a 7.8% increase. The F‐layer intensity, peak VER, and the entire‐layer intensity of OI557.7 dayglow decrease by approximately −27.5%, −32.4% and −17.4%, respectively. The response of the dayglow also depends on longitude and is accompanied by a southward meridional wind. Plain Language Summary: The atomic oxygen dayglow emissions at 630.0 and 557.7 nm are the brightest airglows in the upper atmosphere and important subjects of research. They indicate the connection between the thermosphere and ionosphere as they are influenced by both plasma and neutral species. Understanding this connection is crucial for studying the effects of space weather. During geomagnetic storms, increased Joule heating and particle heating in the polar regions cause the expansion of the upper atmosphere. This interaction disrupts the ionosphere, affecting the 630.0 and 557.7 nm airglows. The Michelson Interferometer for Global High‐Resolution Thermospheric Imaging onboard the Ionospheric Connection Explorer simultaneously gathers data from both dayglow emissions without the need for duty cycling or scanning. This study examined the response of both dayglow to a moderate geomagnetic storm on 27 August 2021. The results enhance our understanding of thermosphere‐ionosphere coupling and space weather impacts. Key Points: The OI630.0 dayglow emission layer moves and extends upward during the geomagnetic stormThe OI630.0 dayglow emission response varies with altitude, increasing above ∼225 km and decreasing below itBoth OI630.0 and OI557.7 dayglow responses depend on longitude, maximizing in the longitude sector around 70°W during this storm [ABSTRACT FROM AUTHOR]

Step‐scan Fourier‐transform infrared spectroscopy (ssFTIR) simultaneously provides the spectroscopic and kinetic information of a given reaction. ssFTIR has been extensively employed to acquire the transient absorption and emission spectra in gas phase for identifying unstable species, for example, various Criegee intermediates, and elucidating the dynamics and kinetics of the reaction, such as the molecular elimination dynamics of haloalkenes and the bimolecular reactions involving chlorine atoms and singlet oxygen atoms. In addition to gaseous studies, ssFTIR has been also utilized to record the time‐resolved difference spectra of the photochemical reactions in condensed phases, such as the photolysis of metal–ligand complexes, photocycles of the retinal proteins, coordination capability of solvents to unstable transient species, chemical reactions of atmosphere‐related molecules in aqua, and the exciplex dynamics of organic light emitting materials. Moreover, my group has pioneered the recording of the transient thermal infrared emission of gold nanostructures upon photoexcitation. The experimental setups and the working principles for probing the time‐resolved infrared absorption and emission in condensed phases will be revealed and a number of studies on chemical, biological, and materials systems will be described. These reported results demonstrate that ssFTIR is a versatile tool for exploring the properties of novel materials and photoreactions in condensed phases. [ABSTRACT FROM AUTHOR]

This work aims to define the optimum n‐decanol fraction in the inlet port and the corresponding engine load for the better emissions and performance characteristics of a partially premixed charged compression ignition (PCCI) engine by response surface methodology (RSM). The numerical model based on multi‐linear regression was established using experimental data. For this, the influence of various proportions of n‐decanol through intake port including 10%, 20%, 30%, and 40% were experimentally investigated besides the primary injection of neem oil biodiesel in the volumetric ratio of 80% diesel and 20% neem biodiesel, namely NB20. The optimization using RSM is exploited to capitalize the brake thermal efficiency (BTE) and diminish the emissions including oxides of nitrogen (NOx), carbon monoxide (CO) emission, smoke opacity, and hydrocarbon (HC) emission. The n‐decanol fraction in the port injection of 31.43% and the engine load in terms of brake power of 2.950 kW were found to be optimum parameters with the maximum desirability of 0.752. The optimal responses for brake‐specific fuel consumption (BSFC), BTE, CO, HC, smoke, and NOx under these operating conditions were found to be 0.305 kg/kWh, 28.8%, 0.145%, 19.61%, 54.85 ppm, and 837.7 ppm, respectively. Likewise, the correlation coefficient R2 values for BSFC, BTE, CO, HC, smoke and NOx have been found to be 99.85%, 99.95%, 93.58%, 90.32%, 99.97%, and 99.93%, respectively. According to the study's findings, the RSM is a realistic method for calculating and enhancing a diesel engine's emission and performance values operating in PCCI mode and using n‐decanol and NB20 as fuels. [ABSTRACT FROM AUTHOR]

For a thorough investigation of the combustion, performance, and emission characteristics of coconut oil distillate biodiesel under various engine loads and a constant engine speed of 1500 rpm, a Kirloskar 4‐stroke, single‐cylinder, the air‐cooled diesel engine is used. A total of three fuel samples, such as 100% biodiesel, B20, and B30 biofuel are used respectively. There is a 5% increase in brake thermal efficiency (BTE) for biodiesel and its blends as compared to diesel. The HC, CO, and Smoke are reduced except NOx. Reduction of harmful gases is possible in biodiesel usage and its blends. It is concluded that emission reductions and alternative diesel fuel is the output of this investigation. [ABSTRACT FROM AUTHOR]

Fast depletion and higher emissions of fossil fuels are posing problems to scientists across the globe. To overcome this, thorough research is needed to find out alternate renewable sources. Biodiesel is such a renewable, biodegradable, and innocuous fuel to meet this global need. Oil extracted from vegetable oil seeds is processed into biodiesel by the transesterification process. The experimental work is carried out to study the performance and emission characteristics of a single‐cylinder, air‐cooled diesel engine by using a mixture of two diverse biodiesels namely Pongamia and Mahua. The results indicate that at higher loads there is a reduction of smoke emission for the 100PM blend (50% Pongamia biodiesel and 50% Mahua biodiesel) along with a 4.4% reduction in brake thermal efficiency when compared to diesel. The smoke is reduced for 100PM by 78.4% and 70.8% and for 50D50PM (50% diesel and 25% each biodiesel) by 71% and 61% at higher loads. From the combustion analysis, it is found that peak cylinder pressure for 100PM and 50D50PM blends are higher when compared with diesel which may be due to the advanced start of injection and ignition of blends. Injection and ignition advance of the blends may be attributed to higher bulk modulus and higher cetane number of biodiesels. [ABSTRACT FROM AUTHOR]

In this present work, the impacts of exhaust gas recirculation (EGR) on exhaust emissions of a diesel engine powered with the blending of butanol with mineral diesel under different engine loads were studied. Experimental tests were performed using butanol‐diesel blends on a single cylinder, constant speed, direct injection (DI) unmodified diesel engine at different proportions by vol%. A higher alcohol—Butanol of 10%, 20%, and 30% blended with mineral diesel fuel. Three different EGR rates of 10 to 30% were employed to reduce the oxides of nitrogen (NOx) emissions that prevailed at higher engine loads. Experimental results revealed that by increasing the EGR rates reduces nitrogen oxide emissions by up to 32% at higher loads. Whereas smoke opacity barely raised to an EGR rate of 20%. There was a rise in hydrocarbon (HC) emissions and a slight surge in carbon monoxide (CO) emissions found with butanol‐diesel blends rather than mineral diesel. NOx emissions were decreased by 29% for 70% Diesel + 30% Butanol (Bu30) blend with EGR 30% than mineral diesel fuel. There is an increase in smoke opacity with engine load because of the burning of a higher amount of energy to generate higher brake power. Smoke opacity is decreased to 68.9% using Bu30 than conventional diesel. Overall, it was found that blends of 30% of butanol and 70% of diesel can be employed in existing unmodified diesel engines. [ABSTRACT FROM AUTHOR]

The present study aims on onsite production of hydrogen using electrolysis process in series and using temporary storage to store the gas and induce it at the required flow rate through the inlet manifold in a dual‐fueled engine along with injecting sapodilla oil through the fuel injector. Sapodilla oil biodiesel is prepared via conventional transesterification with standard operating conditions (65°C) reaction temperature, 3 h reaction time, 1.5% by wt. catalyst and 6:1 molar ratio). Diesel, B100 (100% biodiesel), B100 with two sets of hydrogen induction have been tested for its performance and emissions. Through this analysis it was found that the gas emission such as CO, HC, CO2 was greatly reduced compared to the diesel and sapodilla oil when hydrogen was induced but resulted in increase in NOx emission. There was improvement in parameters with increase in hydrogen induction. [ABSTRACT FROM AUTHOR]

This article is a Commentary on Jeffrey et al. (2024), 242: 49–60. [ABSTRACT FROM AUTHOR]

In desert regions like the Middle East, dust has a profound impact on the environment, climate, air quality, and solar devices. The size of dust particles determines the extent of these effects. Dust deposition (DD) measurements show that coarse dust particles with geometric radius r > 10 μm comprise most of the deposited mass. Still, these particles are not represented in the current models that are tuned to fit the observed aerosol optical depth (AOD). As a result, the existing models and reanalysis products underestimate DD and dust emission (DE) almost 3 times. This is the first study to constrain the dust simulations by both AOD and DD measurements to quantify the effect of coarse and fine dust using the WRF‐Chem model. We found that, on average, coarse dust contributes less than 10% to dust shortwave radiative forcing (RF) at the surface but comprises more than 70% of DE. Annual mean net RF over the Arabian Peninsula and regional seas locally reaches −25 W m−2. Airborne fine dust particles with radii r < 3 μm are mainly responsible for the significant dimming (5%–10%) of solar radiation, cooling the surface, and hampering solar energy production. However, dust mass deposition is primarily linked to coarse particles, decreasing the efficiency of photovoltaic panels by 2%–5% per day. Therefore, incorporating coarse dust in model simulations and data assimilation would improve the overall description of the dust mass balance and its impact on environmental systems and solar devices. Plain Language Summary: Most dust emission schemes used in aerosol chemical transport models are constrained primarily by observed aerosol optical depth (AOD) and do not generate enough coarse dust particles. This study represents the first attempt to constrain the dust emission scheme using AOD and dust deposition (DD) measurements conducted at King Abdullah University of Science and Technology (KAUST). By incorporating both AOD and DD observations, we aimed to enhance the accuracy of the dust emission scheme and provide a more comprehensive understanding of dust mass balance and dynamics in the region. We found that accounting for generating coarse and giant dust particles led to a tripling of dust emissions compared with the previous estimates. We assessed the size distribution of dust particles and their impact on shortwave and longwave radiation. We quantified how particles of different sizes contributed to the regional radiative forcing and examined the implications of DD on the performance and efficiency of solar panels for optimizing solar energy systems in dust‐prone regions. Key Points: Models and reanalysis products underestimate coarse dust emission and dust deposition by 2–3 timesFine dust affects radiation, but coarse dust dominates mass deposition ratesAtmospheric dust dims solar radiation, and coarse dust causes the soiling of solar panels [ABSTRACT FROM AUTHOR]

Two compounds, Na3[Eu(DPA)3] ⋅ 14H2O and [Eu(DPA)(HDPA)(H2O)2] ⋅ 4H2O, were created and the structure determined using single crystal X‐ray diffraction. The single crystal luminescence properties were compared and related to the Eu3+ coordination geometry. The formation of single crystals from solutions of Eu(CF3SO3)3 and H2DPA was found change with the pH value of the H2DPA solution. Mixtures of Na3[Eu(DPA)3] ⋅ 14H2O and [Eu(DPA)(HDPA)(H2O)2] ⋅ 4H2O were observed with a pH ratio between the two structures. While visual inspection showed that all samples contained both Na3[Eu(DPA)3] ⋅ 14H2O and [Eu(DPA)(HDPA)(H2O)2] ⋅ 4H2O, the PXRD and luminescence data did not immediately reveal that the samples were pure. Having discovered that the samples were indeed mixtures, quantification was attempted by Rietveld refinement of the PXRD data, and the luminescence spectra were compared to those from single crystals. As the data was not found to reveal that the samples were mixtures, even though we knew that this was the case, we must urge caution when inferring structure‐property relationships from powder samples. In this case we were able to isolate monophasic systems and do a comparative study, but this requires that the samples are identified as mixtures. [ABSTRACT FROM AUTHOR]

The excellent luminescence properties and structural dynamics driven by the stereoactivity of the lone pair in a variety of low‐dimensional ns2 metal halides have attracted growing investigations for optoelectronic applications. However, the structural and photophysical aspects of the excited state associated with the lone pair expression are currently open questions. Herein, zero‐dimensional Sn‐based halides with static stereoactive 5 s2 lone pairs are selected as a model system to understand the correlations between the distinctive lone pair expression and the excited‐state structural relaxation and charge carrier dynamics by continuous lattice manipulation. Lattice compression drives 5 s2 lone pair active switching and self‐trapped exciton (STE) redistribution by suppressing excited‐state structural deformation of the isolated SnBr42− units. Our results demonstrate that the static expression of the 5 s2 lone pair results in a red broadband triplet STE emission with a large Stokes shift, while its dynamic expression creates a sky‐blue narrowband emission dominated by the radiative recombination of singlet STEs. Our findings and the photophysical mechanism proposed highlight the stereochemical effects of lone pair expression in controlling light emission properties and offer constructive guidelines for tuning the optoelectronic properties in diverse ns2 metal halides. [ABSTRACT FROM AUTHOR]

A chloroplatinum complex was arylated to obtain stimuli‐responsive molecular crystals. The resulting arylplatinum complex showed polymorph‐dependent emission, mechano‐ and thermochromic luminescence as well as comproportionation and π‐bridged dimerization. Simple mixing of structurally similar arylplatinum complexes at room temperature resulted in the transfer of their aryl groups (comproportionation), which allowed their mechanochromic profiles to be tuned. We also found that recrystallization of the complex afforded a dimerized product in which two platinum ions are bridged by aryl groups resulting in a very short (3.0466(10) Å) Pt−Pt distance. [ABSTRACT FROM AUTHOR]

Compression ignition engines are currently optimized to run on petrodiesel fuel, but due to its increasing demand and depletion of fossil fuel reserves, alternative fuels must be utilized. In this article, an attempt was made to optimize the operating parameters of an unmodified compression ignition engine fueled with linseed methyl ester biodiesel. The input parameters were compression ratio, load, and fuel blend, while output responses included brake‐specific fuel consumption (BSFC), brake thermal efficiency (BTE), and exhaust gas temperature (EGT), peak cylinder pressure (PCP), the rate of pressure rise (RPR), and net heat release rate (NHR), hydrocarbon (HC), carbon monoxide (CO), NOx, and Smoke. The aim was to determine the optimal combination of input parameters for minimal emissions and better performance and combustion parameters, with a minimum number of experiments. The study used Taguchi's L9 orthogonal array with a grey relational analysis approach (GRA) to obtain the optimum combination of input parameters. The study found that fuel blend B10, CR 18, and load 100% were the optimal input parameter combinations using the TGRA method. The S/N ratio analysis of grey relational grade (GRG) showed the optimal input factor levels to be fuel B10, CR 16, and load 100%, which was confirmed by the AHP method. The analysis of variance (ANOVA) showed that the load was the most influential factor, followed by CR and fuel. The confirmatory results showed an improvement of 56.1%, indicating that biodiesel can be efficiently used in an unmodified compression ignition engine by varying these influencing factors. [ABSTRACT FROM AUTHOR]