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The use of vehicle tires has been identified as a major source of microplastics in the environment and an increasing source of urban particulate air pollution. In light of increasing traffic volumes, increasingly heavier and more powerful vehicles due to trends and electrification, and the lack of tire wear regulation, methods to estimate and monitor changes in national emissions are needed as input for environmental impact assessments. Emission estimations of tire wear are made either based on the mileage approach or the sales approach. This study aims to investigate if and how the mileage approach can be improved by using emission factors for passenger cars and LDVs based on our own measurements and emission factors from the literature for HDVs and buses. An approach with emission factor adjustments based on weight and number of tires in combination with highly detailed mileage data has been evaluated. Sales approach calculations have been used to validate the method. A secondary aim was to use the new mileage approach framework to calculate the national tire wear emissions for Sweden. These calculations resulted in slightly lower total emissions than previous estimations provide, but with higher emissions for passenger cars and light-duty vehicles, and lower emissions for heavy-duty vehicles and motorcycles. Passenger cars constitute more than half of the total emissions. It is concluded that even though the framework offers greater detail, thus increasing the possibilities to adjust for changes in emission factors and mileages in specific vehicle categories, the challenges posed by such factors as the lack of measured emission factors for heavy-duty vehicles and uncertainties regarding the quality of mileage statistics makes the estimations uncertain.

This research proposes a fuel system conversion from a carburetor to an electronic fuel injection (EFI), to save fossil fuels using gasoline-ethanol combined with water injection. Beneficial as an offer for Indonesian motorcycle environmental friendliness in terms of exhaust emissions. The goal of this study is to improve engine performance and accommodate technology for the deployment of ethanol gasoline implementations. The experiment was conducted using fuel with a ration octane number (RON) of 92, gasoline-ethanol was executed up to E25 then applied water injection (Wi). The results show that converting a conventional carburetor to EFI and additional water injection increases engine performance, mileage, and reduces exhaust emissions.

Shang et al. (2024) recently suggested to include nitrous oxide (N2O) emissions during the fallow period to better estimate N2O emission factors (EFs). We however highlighted several pitfalls of the proposed adjusted EFs for croplands in the specific case of dry subhumid, semiarid, and arid regions with dry fallow periods, these regions covering about 47% of the Earth's terrestrial area.

Microplastics are released from terrestrial surfaces into the atmosphere where they are conveyed via wind and may be deposited, remain in the atmosphere, or disperse across long ranges. Because of this high atmospheric contamination, inhalation is one of the primary exposure pathways for microplastics. Inhalation exposure is controlled by two key factors: a) the quantity of microplastics available to be emitted from terrestrial environments to the atmosphere, and b) the factors that influence the potential of this emission occurring. The reported concentrations of microplastics on terrestrial surfaces vary widely based on monitoring methodology and characteristics of the capture region, making it difficult to estimate potentially emitted microplastics. Concentrations of traditional atmospheric aerosols such as particulate matter (PM10, PM 2.5), NOx, SOx, and heavy metals, vary based on region characteristics such as climate, land use, socioeconomic vulnerability, and urban sources including landfills, wastewater treatment plants, and hazardous waste sites. However, microplastics have unique properties: low density and high hydrophobicity, which may alter their emission mechanisms and spatial distribution. Thus, it is unknown how fluctuation in these exposure factors could affect the emission potential of microplastics, influencing concentration levels in the atmosphere. Additionally, the fundamental emission mechanisms and factors that could affect the emission potential of microplastics into the atmosphere are unclear. A wide body of literature models the atmospheric emission of particulate pollutants; however, no model to date adapts these traditional emission models by accounting for the unique properties of microplastics. The overall objective of the dissertation is to improve the mechanistic understanding of microplastic emission into the atmosphere, and the factors which may affect the exposure of human populations to higher levels of emitted microplastics in

Road dust is an important source to airborne particles in the Nordic countries. It consists of wear products from road pavement, tyres, brakes, traction sand, salt and dust dragged in from adjacent unbound roads or deposited from nearby or long distance dust sources, like building sites and farmland. The cold climate in the Nordic countries enhances the formation of road dust compared to most European countries, since it promotes the use of studded tyres, which abrades the road surfaces, and winter maintenance where dust forming material is added to the road surfaces. The NORDUST II project has aimed to enhance knowledge about road dust emissions through extensive investigations, including laboratory and field studies, measurements, modeling, and future scenarios. An initial work package summarized current knowledge on mitigating road dust emissions. It found that dust binding solutions are most effective during acute dust episodes, while sweeping is beneficial on a seasonal basis. Preventive measures during autumn and winter can reduce airborne dust in spring. A core component of the project was experimental parameterization of processes in the NORTRIP emissions model. Studies revealed that vehicle weight and speed significantly influence particulate matter (PM) emissions, with heavier vehicles and higher speeds increasing emissions. The type of tire and road surface properties also play crucial roles.Experiments showed that winter sand is quickly crushed into finer fractions when driven over, but only a small portion of the sand mass is crushed. Coarse particles are removed more efficiently than finer particles at low speeds, but all particles are removed at speeds above 20 km/h. A field test in Linköping, Sweden, examined the removal of the dust binder CMA by traffic. Results indicated that the NORTRIP model could largely replicate the impact of traffic migration on CMA concentrations., Research funding provided by Statens vegvesen, Trafikverket, Väylävirasto, Vegagerðin and Vejdirektoratet.

We report the first detection, at very high significance (23 sigma), of the cross-correlation between cosmic shear and the diffuse x-ray background, using data from the Dark Energy Survey and the ROSAT satellite. The x-ray cross-correlation signal is sensitive to the distribution of the surrounding gas in dark matter halos. This allows us to use our measurements to place constraints on key physical parameters that determine the impact of baryonic effects in the matter power spectrum. In particular, we determine the mass of halos in which feedback has expelled half of their gas content on average to be log10(Mc/M circle dot) 10 ( M c /M circle dot ) = 13 .643 & thorn;0 .081 -0.12 and the polytropic index of the gas to be Gamma = 1.231 & thorn;0.015 -0.011 . This represents a first step in the direct use of x-ray cross-correlations to obtain improved constraints on cosmology and the physics of the intergalactic gas.

Bright near-infrared-emitting Ag2S nanocrystals (NCs) are used for in vivo temperature sensing relying on a reversible variation in intensity and photoluminescence lifetime within the physiological temperature range. Here, to gain insights into the luminescence and quenching mechanisms, we investigated the temperature-dependent luminescence of Ag2S NCs from 300 to 10 K. Interestingly, both emission and lifetime measurements reveal similar and strong thermal quenching from 200 to 300 K, indicating an intrinsic quenching process that limits the photoluminescence quantum yield at room temperature, even for perfectly passivated NCs. The low thermal quenching temperature, broadband emission, and multiexponential microsecond decay behavior suggest the optical transition involves strong lattice relaxation, which is consistent with the recombination of a Ag+-trapped hole with a delocalized conduction band electron. Our findings offer valuable insights for understanding the optical properties of Ag2S NCs and the thermal quenching mechanism underlying their temperature-sensing capabilities.

Recycling of organic resources into agriculture has the potential to greatly increase nutrient use efficiency and improve soil carbon balance, but improper management can have adverse effects on the environment. Agriculture therefore faces large challenges to increase yields while decreasing these emissions to the environment. In this paper, we review (i) the availability and composition of organic resources, (ii) their agronomic value and risk of emissions, (iii) potential measures to reduce their emissions, and (iv) future challenges to support farmers and policy makers. The total amount of organic resource applied to soil amounted on average 41 kg nitrogen per ha agricultural land, 9 kg phosphorus per ha, and 456 kg carbon per ha in EU-27 + UK in 2017. Solid pig and cattle manures and cattle slurry are the most used organic resources. The availability of new organic resources from food processing, sewage sludge, municipal bio-wastes, and upcoming manure treatment techniques as fertilizer or soil conditioner is expected to strongly increase over the coming decade. Insight is needed into the composition of organic resources, the plant-availability of nutrients, the degradability of organic matter and the presence of contaminants. Measurement techniques become available to characterize soils, manures, crops, and emissions to the environment. However, the interpretation, and integration of data, and recommendations to farmers and policymakers using large amounts of data is expected to become more and more challenging. Many measures are available to improve nutrient and carbon management and to reduce emissions, including proper application, technological measures and structural changes in agriculture. For many measures, there is a risk of trade-offs that could lead to pollution swapping at different scales. We should focus on finding synergies between measures and no-regret management choices to develop effective mitigation strategies. The main future challenge for m

The world's population growth drives the need for new housing, infrastructure, and industries, with concrete being one of the most widely used building materials globally. However, today's concrete is not sustainable from a climate perspective, thus efforts are made to reduce the climate impact from the construction sector. The largest portion CO2 emission is generated from cement production and accounts for approximately 8% of global emissions. To reduce carbon dioxide emissions, development of alternative binders and techniques such as fossil-free transport and carbon storage is ongoing. Despite this, knowledge of how climate-improved concrete affects appearance is limited. This study examines the visual effects of climate-improved concrete with blast furnace slag as a binder on various facade techniques to contribute to sustainable construction. Through experiments with 12 different facade techniques, the results show that climate-improved concrete does not differ drastically in appearance compared to traditional concrete. The climate improved concrete has a lighter color tone and affects imprints during casting on different form materials. The conclusion is that climate-improved concrete has the potential to reduce climate impact without deteriorating visual properties compared to traditional concrete., Världens befolkningsökning är en drivande faktor bakom det växande behovet av nya bostäder, infrastruktur, industrier, anläggningar samt byggnader för olika verksamheter och näringsliv. Betong, som är ett av världens mest använda byggnadsmaterial, är idag inte hållbar utifrån ett klimatperspektiv. Samtidigt som befolkningen växer är det avgörande att minska klimatpåverkan och uppnå klimatmålen gällande byggande. Cement är den komponenten i betong som utgör den största klimatpåverkan med det högsta koldioxidutsläppet som står för cirka 8% av de totala globala utsläppen. För att reducera koldioxidutsläppen i betongproduktionen pågår en utveckling av alternativa bindemedel som ersätter en del av portlandcementen som används idag. Utveckling pågår även kring fossilfri transport, koldioxidlagring och annan innovativ teknik. Idag finns det begränsad kännedom om hur utseendet på betongfasader påverkas vid användning av klimatförbättrad betong. Syftet med arbetet är att bidra till ett hållbart byggande, genom att undersöka det estetiska uttrycket vid användning av klimatförbättrad betong med masugnsslagg som alternativt bindemedel vilket ersätter en del av portlandcementen. Olika varianter av fasadtekniker såsom handbearbetad, pigmenterad, frilagd, grafisk betong samt gjutning mot olika typer av formmaterial ligger till grund för undersökningen av det estetiska uttrycket. Målet för arbetet är stödja arkitekter, ingenjörer och andra sakkunniga med kunskap samt inspiration för arbetet mot ett klimatsmart byggande. Resultatet har erhållits genom experiment i form av provgjutningar av 12 olika fasadtekniker där hälften har gjutits med traditionell betong respektive klimatförbättrad betong. Utförandet av experimenten har varit möjligt genom ett samarbete med Heidelberg Materials Precast Abetong AB, Pigmentec AB och Graphic Concrete. Användningen av klimatförbättrad betong visar inga drastiska skillnader i utseende jämfört med traditionell betong. De olika fasadteknikerna visar p

Mikroplastförorening från textilier utgör ett betydande hot mot marina ekosystem, vilket har fått ökad uppmärksamhet från både forskare och allmänheten. Denna studie belyser vikten av val av skärmetod under produktionsfasen för att minska frigörandet av mikrofiber. Dessa insikter är avgörande för textilindustrin, särskilt modeföretag, som strävar efter att minimera sin miljöpåverkan. Studien undersöker effekterna av olika skärmetoder och materialorienteringar för frigörandet av mikrofibrer vid tvätt med användning av Textil och textilprodukter – Mikroplaster från textila källor – Del 1:Bestämning av materialförlust från tyger vid tvätt (ISO 4484-1:2023). Tygets sammansättning som används i denna studie är 83% återvunnen polyamid och 17% elastan i en single-jerseykonstruktion med en vikt på 170g/m². Studiens resultat visar på en korrelation mellan skärmetoder och omfattningen av mikrofiberförlust. Användningen av bandsåg är kopplad till ökad känslighet för mikrofibersläpp, jämfört med ultraljudsteknik som resulterade i de lägsta nivåerna. Dessutom påverkar varp- och väftriktningen mikrofibersläpp olika beroende på vilken skärmetod som används. Genom att anta lämpliga skärmetoder och ta hänsyn till materialorientering kan textilindustrin ta proaktiva steg för att minska mikrofiberföroreningar och dess skadliga effekter på marina miljöer., Microplastic pollution from textiles poses a significant threat to marine ecosystems, which has received increased attention from both scientists and the public. This research highlights the importance of considering cutting methods during the production phase to mitigate microfiber release. These insights are critical for the textile industry, particularly fashion companies, aiming to minimize their environmental footprint. This study investigates the impact of different cutting methods and material orientations on the release of microfibers during washing with the use of Textiles and textile products - Microplastics from textile sources - Part 1: Determination of material loss from fabrics during washing (ISO 4484-1:2023). The fabric composition used in this study is 83% recycled polyamide and 17% elastane in a single-jersey construction weighing 170 g/m². The findings of the study demonstrate a correlation between cutting methods and the extent of microfiber shedding. The utilization of a bandknife cutting method is associated with heightened susceptibility to shedding, contrasted by the ultrasonic cutting technique which yields the lowest levels of microfiber release. Moreover, the directional orientation of warp and weft affects microfiber release differently depending on the cutting methods used. By adopting appropriate cutting techniques and considering material orientation, the textile industry can take proactive steps towards reducing microfiber pollution and its detrimental effects on marine environments.

In this study, experimental engine tests were conducted to investigate the combustion, performance, and emission characteristics of a diesel engine using a fuel blend composed of diesel, biodiesel, and fusel oil. In the study, which was carried out by using fuels obtained from different wastes together in a diesel engine. Seven different fuels were prepared for experiments by adding waste cooking oil (30% and 50%) and fusel oil (5% and 10%) by volume to commercial diesel fuel. The tests were carried out on the Lombardini LDW 1003 engine, a three-cylinder diesel engine, at four different engine loads (10, 20, 30, and 40 Nm), and a constant speed (2000 rpm). The experimental results revealed that the use of WCO generally led to increased NOx emissions which generally decreased with the fusel oil addition to the fuel mixture. Considering diesel fuel as a reference at maximum load conditions, there was a 12.63% increase in NOx emissions with 50% WCO. A 2.45% decrease in NOx emissions was achieved by adding 10% fusel oil. Furthermore, HC emissions decreased with the addition of both fusel oil and WCO at all load levels. When diesel fuel is taken as a reference at maximum load conditions, a 90% reduction in HC emissions was achieved by adding 50% WCO, and a 50% reduction in HC emissions was achieved by adding 10% fusel oil. Additionally, when diesel fuel is taken as a reference at maximum load condition, it was observed that a 0.05% increase in the maximum cylinder pressure value with the addition of 50% WCO and a 2.09% increase in the maximum cylinder pressure value with the addition of 10% fusel oil. © The Author(s) 2024., Türkiye Bilimsel ve Teknolojik Araştırma Kurumu, TÜBİTAK

The increasing popularity of luminescent nanothermometry in recent years can be attributed to its application potential in biomedicine. In response to this need, we describe a biocompatible bimodal luminescent thermometer that operates in ratiometric and luminescence lifetime modes based on particles of MgTiO3:Cr3+,Nd3+@SiO2. The introduction of Cr3+ and Nd3+ dopants enabled the luminescence of Ti3+ ions to be observed, and the difference in the thermal quenching rates of Cr3+ (4T2→4A2), Ti3+ (2T2→2E) and Nd3+ (4F3/2 → 4I11/2) ions enabled the ratiometric thermometers. The highest sensitivity reaching SR = 1.00%K−1 was obtained for MgTiO3:0.1 % Cr3+, 0.1 % Nd3+ at 203 K. The shortening of the lifetime of the 4T2 level of Cr3+ ions associated with its thermal depopulation allows to develop a lifetime-based thermometer with a relative sensitivity reaching 0.85–1.18%K−1 in the physiological temperature range. The deposition of a SiO2 shell on a MgTiO3:Cr3+,Nd3+ did not introduce significant changes in the shape of the emission spectrum and slightly elongates the lifetime by reducing the probability of surface-related nonradiative processes. More importantly, the thermometric performance of this luminescence thermometer was preserved. The low cytotoxicity of the obtained materials underlines their potential in bioapplications of the described luminescent thermometers.

Presentatie gegeven op 24 mei tijdens een webinar over de invloeden van nieuwe stalsystemen op de eigenschappen, emissies en waarde van mest. Deze slides gaan over het effect van snelle mestverwijdering uit stallen op broeikasgas- en ammoniakemissie en organische stofafbraak in mest. Het onderzoek richt zich op de emissies uit mest die vrijkomen in de eerste 70 uur na uitscheiding.

The circumgalactic medium (CGM) and intergalactic medium (IGM), the tenuous gas surrounding galaxies represent a significant portion of matter in the universe as indicated by both theoretical and observational studies. This faint and diffuse gas is not well studied since it is very challenging to observe. Studying the CGM is essential for understanding astrophysical principles that govern the formation and evolution of stars and galaxies throughout the universe. It is believed to be the reservoir of gas and material that is both the source and regulator of star-forming fuel, controlling the exchange between the intergalactic medium (IGM) between galaxies and interstellar medium (ISM) within galaxies. This dissertation focuses on advancing our understanding of these processes through ultraviolet (UV) spectroscopic CGM emission line observations in high redshift galaxies in addition to instrumentation work for balloon-borne and space telescopes that target low redshift galaxies. This thesis describes four distinct but interrelated projects that combine observational astronomy, instrument building, and technology development. First, I analyzed data taken with the Palomar Cosmic Web Imager (PCWI) that observed the CGM around four different quasi-stellar object (QSO) or quasar pairs (z$\sim$2.3) during a period of peak star formation, cosmic noon. I then used the data to map the Lyman-alpha (Ly$\alpha$) emission intensity, kinematics, and surface brightness as a function of distance from the brighter QSO of each pair. Observations of galaxies throughout cosmic time serve as puzzle pieces in understanding galactic evolution. This study adds to the growing archive of galactic emission line studies to pinpoint redshift specific characteristics that drive the behavior of star formation. Second, I designed and built a new in-flight calibration system for the balloon-borne telescope FIREBall-2 (Faint Intergalactic-medium Redshifted Balloon) that flew in the September 2023 laun

[Abstract] The decarbonisation of the maritime sector is one of the world's priorities to reduce the volume of polluting emissions. The basis of this decarbonisation is the adaptation of existing ships to emission control regulations by means of transformations, installation of new equipment, development of new low-emission fuels and development of the infrastructure that makes the supply of this new generation of fuels feasible. In addition, hydrogen is the energy vector for all these new technologies, and its role over the next 30 years needs to be addressed. In a changing global situation such as the one we are currently experiencing; this article has the objective of making a review paper on the different fuels currently being used in the maritime sector and the existing alternatives. It also discusses the situation and the impact the current environmental situation has on the world ship order book, both in terms of legislation and economics. As a conclusion, the Liquefied Natural Gas (LNG) will have a very important role to play as a bridge between the current situation and the development of hydrogen technology. Hydrogen is an energy vector that can achieve the decarbonisation objectives by 2050. Storage problems, lack of infrastructures to supply it and the development of technology and regulations are the major challenges it will have to face. Biofuels also present a serious proposal for the decarbonisation of the sector, and the role of hydrogen in their composition, is essential to achieve green fuel generation.

We report on the optical properties of a CsPbBr3 polycrystallinethin film on a single grain level. A sample composed of isolated nanocrystals(NCs) mimicking the properties of the polycrystalline thin film grainsthat can be individually probed by photoluminescence spectroscopywas prepared. These NCs were analyzed using correlative microscopyallowing the examination of structural, chemical, and optical propertiesfrom identical sites. Our results show that the stoichiometry of theCsPbBr(3) NCs is uniform and independent of the NCs'morphology. The photoluminescence (PL) peak emission wavelength isslightly dependent on the dimensions of NCs, with a blue shift upto 9 nm for the smallest analyzed NCs. The magnitude of theblueshift is smaller than the emission line width, thus detectableonly by high-resolution PL mapping. By comparing the emission energiesobtained from the experiment and a rigorous effective mass model,we can fully attribute the observed variations to the size-dependentquantum confinement effect.

Focused beams of electrons, which act as both sources and sensors of electric fields, can be used to characterize the electric response of complex photonic systems by locally probing the induced optical near fields. This functionality can be complemented by embracing the recently developed vortex electron beams (VEBs), made up of electrons with orbital angular momentum, which could, in addition, probe induced magnetic near fields. In this work we revisit the theoretical description of this technique, dubbed vortex electron energy-loss spectroscopy (v-EELS). We map the fundamental, quantum-mechanical picture of the scattering of the VEB electrons to the intuitive classical models, which treat the electron beams as a superposition of linear electric and magnetic currents. We then apply this formalism to characterize the optical response of dielectric nanoantennas with v-EELS. Our calculations reveal that VEB electrons probe electric or magnetic modes with different efficiency, which can be adjusted by changing either beam vorticity or acceleration voltage to determine the nature of the probed excitations. We also study a chirally arranged nanostructure, which in the interaction with electron vortices produces dichroism in electron-energy-loss spectra. Our theoretical work establishes VEBs as versatile probes that could provide information on optical excitations otherwise inaccessible with conventional electron beams.

Since its inception more than 2 decades ago, proton-transfer-reaction mass spectrometry (PTR-MS) has established itself as a powerful technique for the measurements of a wide range of volatile organic compounds (VOCs) with high time resolution and low detection limits and without the need for any sample pre-treatment. As this technology has matured and its application become more widespread, there is a growing need for accurate and traceable calibration to ensure measurement comparability. As a result of the large number of VOCs detectable with PTR-MS, it is impractical to have a calibration standard or standards that cover all observable compounds. However, recent work has demonstrated that quantitative measurements of uncalibrated compounds are possible provided that the transmission curve is accurately constrained. To enable this, a novel traceable multi-component gas reference material containing 20 compounds spanning a mass range of 32 to 671 has been developed. The development and compositional evolution of this reference material are described along with an evaluation of its accuracy and stability. This work demonstrates that for the majority of components the accuracy is < 5 % (most < 3 %; < 10 % for hexamethylcyclotrisiloxane (D3-siloxane) and 1,2,4-trichlorobenzene - 1,2,4-TCB) with stabilities of > 2 years (> 1 year for acetonitrile, methanol and perfluorotributylamine - PFTBA).

For the past few years, the energy demand has been raised progressively all over the world. Numerous extensive studies have been conducted to reduce the rate of emission in diverse alternative fuels. However, currently numerous investigations have been undertaken to diminish the harmful impact of the exhaustion of gas emissions from the utilization of diesel, Liquefied Petroleum Gas (LPG), and gasoline fuels. Hence, a novel triple fuel system (i.e. petrol, diesel, and LPG) is proposed based on three different analyses, namely energy, exergy, and emission at diverse load (kg) conditions. Nonetheless, the validations of each method are performed by single-cylinder four-stroke diesel engines at optimized conditions. Moreover, the analyses are performed at a constant speed rate of 1500rpm, with six diverse engine loads (kg) of about (2.5, 5, 7.5, 10, 12.5, and 13.50 kg). Various measurable factors such as emission rate, heat transfer rate, and cylinder pressure are determined to estimate the steady state condition. Finally, various parameters such as brake thermal efficiency, specific fuel consumption, and exhaust gas analysis are performed and compared with single fuel, dual fuel, and the proposed triple fuel modes to determine the efficiency of the system., En los últimos años, la demanda de energía ha aumentado progresivamente en todo el mundo. Se han realizado numerosos estudios exhaustivos para reducir la tasa de emisiones de diversos combustibles alternativos. Sin embargo, en la situación actual, se están llevando a cabo numerosas investigaciones para disminuir los efectos nocivos del de las emisiones de gases procedentes de la utilización de combustibles como, el diésel, el gas licuado de petróleo (GLP) y la gasolina. A partir de ello, se propone un novedoso sistema de combustible triple (es decir, gasolina, gasóleo y GLP) basado en tres análisis diferentes; energía, exergía y emisiones para diferentes condiciones de carga (kg). Las validaciones de cada método se realizan con motores diésel monocilíndricos de cuatro tiempos en condiciones optimizadas. Además, los análisis se realizan a una velocidad constante de 1.500 rpm con seis cargas diferentes (kg) del motor de aproximadamente (2,5, 5, 7,5, 10, 12,5 y 13,50 kg). Se determinan varios factores medibles, como la tasa de emisión, la tasa de transferencia de calor y la presión del cilindro, para estimar la condición de estado estacionario. Por último, se realizan y comparan varios parámetros, como la eficiencia térmica de frenado, el consumo específico de combustible y el análisis de los gases de escape, con los modos de combustible único, combustible doble y combustible triple propuestos para determinar la eficiencia del sistema.

Artículo firmado por 183 autores. © ESO 2023. We would like to thank the Instituto de Astrofísica de Canarias for the excellent working conditions at the Observatorio del Roque de los Muchachos in La Palma. The financial support of the German BMBF and MPG; the Italian INFN and INAF; the Swiss National Fund SNF; the ERDF under the Spanish MINECO (FPA2017-87859-P, FPA2017-85668-P, FPA2017-82729-C6-2-R, FPA2017-82729-C6-6-R, FPA2017-82729-C6-5-R, AYA2015-71042-P, AYA2016-76012-C3-1-P, ESP2017-87055-C2-2-P, FPA2017-90566-REDC); the Indian Department of Atomic Energy; the Japanese ICRR, the University of Tokyo, JSPS, and MEXT; the Bulgarian Ministry of Education and Science, National RI Roadmap Project DO1-268/16.12.2019 and the Academy of Finland grant no. 320045 is gratefully acknowledged. This work was also supported by the Spanish Centro de Excelencia "Severo Ochoa" SEV-2016-0588 and SEV-2015-0548, the Unidad de Excelencia "María de Maeztu" MDM-2014-0369 and the "la Caixa" Foundation (fellowship LCF/BQ/PI18/11630012), by the Croatian Science Foundation (HrZZ) Project IP-2016-06-9782 and the University of Rijeka Project 13.12.1.3.02, by the DFG Collaborative Research Centers SFB823/C4 and SFB876/C3, the Polish National Research Centre grant UMO-2016/22/M/ST9/00382 and by the Brazilian MCTIC, CNPq and FAPERJ. The Fermi LAT Collaboration acknowledges generous ongoing support from a number of agencies and institutes that have supported both the development and the operation of the LAT as well as scientific data analysis. These include the National Aeronautics and Space Administration and the Department of Energy in the United States, the Commissariat a l'Energie Atomique and the Centre National de la Recherche Scientifique/Institut National de Physique Nucleaire et de Physique des Particules in France, the Agenzia Spaziale Italiana and the Istituto Nazionale di Fisica Nucleare in Italy, the Ministry of Education, Culture, Sports, Science and Technology (MEXT), High Energ, Context. Diffusive shock acceleration (DSA) is the most promising mechanism that accelerates Galactic cosmic rays (CRs) in the shocks of supernova remnants (SNRs). It is based on particles scattering caused by turbulence ahead and behind the shock. The turbulence upstream is supposedly generated by the CRs, but this process is not well understood. The dominant mechanism may depend on the evolutionary state of the shock and can be studied via the CRs escaping upstream into the interstellar medium (ISM). Aims. Previous observations of the gamma Cygni SNR showed a difference in morphology between GeV and TeV energies. Since this SNR has the right age and is at the evolutionary stage for a significant fraction of CRs to escape, our aim is to understand gamma-ray emission in the vicinity of the gamma Cygni SNR. Methods. We observed the region of the gamma Cygni SNR with the MAGIC Imaging Atmospheric Cherenkov telescopes between 2015 May and 2017 September recording 87 h of good-quality data. Additionally, we analysed Fermi-LAT data to study the energy dependence of the morphology as well as the energy spectrum in the GeV to TeV range. The energy spectra and morphology were compared against theoretical predictions, which include a detailed derivation of the CR escape process and their gamma-ray generation. Results. The MAGIC and Fermi-LAT data allowed us to identify three emission regions that can be associated with the SNR and that dominate at different energies. Our hadronic emission model accounts well for the morphology and energy spectrum of all source components. It constrains the time-dependence of the maximum energy of the CRs at the shock, the time-dependence of the level of turbulence, and the diffusion coefficient immediately outside the SNR shock. While in agreement with the standard picture of DSA, the time-dependence of the maximum energy was found to be steeper than predicted, and the level of turbulence was found to change over the lifetime of the SNR., German BMBF, German MPG, Italian INFN, Italian INAF, Swiss National Fund SNF, ERDF under the Spanish MINECO, Indian Department of Atomic Energy, Japanese ICRR, Japanese University of Tokyo, Japanese JSPS, Japanese MEXT, Bulgarian Ministry of Education and Science, National RI Roadmap Project, Academy of Finland, Centro de Excelencia "Severo Ochoa", Unidad de Excelencia "Maria de Maeztu", Fundación "la Caixa", Croatian Science Foundation (HrZZ) Project, University of Rijeka Project, DFG Collaborative Research Centers, Polish National Research Centre grant, Brazilian MCTIC, Brazilian CNPq, Brazilian FAPERJ, DOE, Depto. de Estructura de la Materia, Física Térmica y Electrónica, Fac. de Ciencias Físicas, TRUE, pub

External pressure is one of the key parameters to understand photoemission nanomaterials since the external pressure changes their photoproperties without introducing any chemical treatment. Here, we computationally elucidated the effects of the external pressure on structures, orbitals, photoproperties, and vibrational dynamics of a silicon vacancy (SiV) diamond nanoslab. We studied its attributes not only on the ground state at 0 K but also on the excited state around room temperature (RT) using an ab initio molecular dynamics simulation. We directly and mechanically pressed the SiV diamond nanoslab fluctuating around RT to mimic an actual external pressure usually generated in an anvil cell at RT. We found that the compression induces the shrunk SiV defect structures, the rearranged defect orbital energies, the switch of the optical transition from the SiV–SiV excitation to the nanoslab–SiV excitation, the hybridization of the SiV with nanoslab carbon (C) orbitals, and the blue shift and the smaller intensity of the spectra of the Si atom oscillation and the inner C–C bond vibration. The energies of absorption, emission, and zero-phonon line do not change monotonically but have the maxima below a 7%-compression. Especially, the absorption energy differs more between 0 K and RT as the compression increases, while the largest deviation between 0 K and RT in the emission energy appears below the 7%-compression. It is remarkable that all of these changes are caused only by the mechanical compression and that the compression differently pronounces the temperature effect. The obtained insights will provide a way to effectively control a split-vacancy center to be a promising single-photon source for nanoscale optical measurements of temperature and pressure in a compressed nanoscale material.

The 2015 Paris climate accord (Paris Agreement) is meant to control our planet’s rising temperature to limit climate change. But it may be doing the opposite in permitting a slow phase-in of CO2 emission mitigation. The accord asks its 195 national signatories to specify their emission reductions and to raise those contributions over time. However, there is no mechanism to enforce these pledges. This said, the accord puts dirty energy producers on notice that their days are numbered. Unfortunately, this “use it or lose it” message may accelerate the extraction and sale of fossil fuels and, thereby, permanently worsen climate change. Our paper uses a simple OLG model to illustrate this long-noted, highly troubling Green Paradox. Its framework properly treats climate damage as a negative externality imposed by today’s generations on tomorrow’s—an externality that is, in part, irreversible and, if large enough, can tip the climate to a permanently bad state. Our paper shows that delaying abatement can be worse than doing nothing. Indeed, it can make all generations worse off. In contrast, immediate policy action can make all generations better off. Finally, we question the standard use of infinitely lived, single-agent models to determine optimal abatement policy. Intergenerational altruism underlies such models. But its assumption lacks empirical support. Moreover, were such altruism widespread, effective limits on CO2 emissions would, presumably, already be in place. Unfortunately, optimal abatement prescriptions derived from such models can differ, potentially dramatically, from those actually needed to correct the negative climate externality that today’s generations are imposing on tomorrow’s

Seit der Bundesrat gefordert hat, dass ab 2030 nur noch emissionsfreie Fahrzeuge zugelassen werden sollen, hat die Debatte um den richtigen Weg in die Zukunft der Mobilität an Fahrt aufgenommen. Die Autoren begründen, warum die Bundesrats-Initiative, die de facto einem Zulassungsverbot für neue Benzin- und Dieselfahrzeuge gleichkommt, genau den richtigen Innovationsimpuls setzt - und es falsch wäre, ihn mit einseitigen Festlegungen zu verbinden.

Global energy justice remains far out of reach. If the goal of energy justice is the universal, equitable, and democratic provision of safe, affordable, and sustainable energy services, the international community currently lacks the physical, ideational, or governance infrastructure necessary for its realization. Instead, access to energy remains radically unequal, continuing greenhouse gas emissions are creating intergenerational sabotage, and fossil fuel revenues routinely corrupt democratic politics. In addition to distributive injustice, global energy governance also creates dilemmas of procedure and recognition that are our focus. Here, we first identify inherent tensions between local democratic sovereignty and global energy justice and then argue that existing energy governance infrastructures often amplify powerful actors’ leverage over the energy choices and strategies of less powerful communities. We conclude by discussing the design of a governance infrastructure that could promote climate mitigation and energy access goals without exploiting international inequalities in ways that risk undermining justice.

Im vergangenen Jahr waren die Zuwachszahlen im Bereich der Elektromobilität in Deutschland höher als jemals zuvor. Das enorme Wachstum ist vor allem der EU-Verordnung zur Flottenemissionsnorm zu verdanken. Die Elektromobilität hat damit einen wichtigen Schritt gemacht und gezeigt, dass sie das Potenzial hat, den Verbrennungsmotor bald zu verdrängen. Doch allein ein sehr hoher Marktanteil an Elektroautos genügt nicht, um die mittelfristigen deutschen Klimaschutzziele zu erreichen. Dies ist eine der zentralen Aussagen der Autoren des vorliegenden Impulspapiers. Sie empfehlen, dass die Europäische Union Herstellern weiterhin ambitionierte Zielvorgaben für emissionsarme Pkw machen sollte, damit schon im Jahr 2030 annähernd alle neu zugelassenen Pkw elektrisch angetrieben werden. Autos mit Hybridantrieb sind auf diesem Weg maximal eine wichtige Übergangstechnologie. Zentrale Voraussetzung ist zudem, dass die derzeitigen Ladevorgänge erleichtert werden, damit der Umstieg auf Fahrzeuge mit alternativem Antriebskonzept deutlich attraktiver wird.

We use medium-resolution JWST/NIRSpec observations from the Cosmic Evolution Early Release Science Survey to place the first constraints on dust attenuation and star formation based on Paschen lines for a sizable sample of 63 galaxies at redshifts z = 1.0-3.1. Our analysis indicates strong correlations between the Balmer decrement, H alpha/H beta, and line ratios that include Paschen lines (i.e., Pa alpha/H beta, Pa beta/H beta, and the Paschen decrement, Pa alpha/Pa beta), suggesting that the former is sensitive to the overall dust obscuration toward H ii regions in high-redshift galaxies. The line ratios are used to derive nebular reddening, E(B - V)(neb), and star formation rates (SFRs). There is marginal evidence that the SFRs deduced from Paschen lines may exceed by approximate to 25% those derived from Balmer lines alone, suggesting the presence of star formation that is optically thick in Balmer lines, though deeper observations are needed to confirm this result. Using the Paschen-line constraints on the bolometric SFRs, we reevaluate the relationship between dust obscuration and UV spectral slope, and find a reddening of the UV continuum that, on average, follows the SMC extinction curve. This analysis highlights the need for deeper spectroscopy of more representative samples to evaluate nebular dust attenuation and bolometric SFRs in high-redshift galaxies, and their relationship to the reddening of the UV continuum.

We report on the optical properties of a CsPbBr3 polycrystallinethin film on a single grain level. A sample composed of isolated nanocrystals(NCs) mimicking the properties of the polycrystalline thin film grainsthat can be individually probed by photoluminescence spectroscopywas prepared. These NCs were analyzed using correlative microscopyallowing the examination of structural, chemical, and optical propertiesfrom identical sites. Our results show that the stoichiometry of theCsPbBr(3) NCs is uniform and independent of the NCs'morphology. The photoluminescence (PL) peak emission wavelength isslightly dependent on the dimensions of NCs, with a blue shift upto 9 nm for the smallest analyzed NCs. The magnitude of theblueshift is smaller than the emission line width, thus detectableonly by high-resolution PL mapping. By comparing the emission energiesobtained from the experiment and a rigorous effective mass model,we can fully attribute the observed variations to the size-dependentquantum confinement effect.

We report on the optical properties of a CsPbBr3 polycrystallinethin film on a single grain level. A sample composed of isolated nanocrystals(NCs) mimicking the properties of the polycrystalline thin film grainsthat can be individually probed by photoluminescence spectroscopywas prepared. These NCs were analyzed using correlative microscopyallowing the examination of structural, chemical, and optical propertiesfrom identical sites. Our results show that the stoichiometry of theCsPbBr(3) NCs is uniform and independent of the NCs'morphology. The photoluminescence (PL) peak emission wavelength isslightly dependent on the dimensions of NCs, with a blue shift upto 9 nm for the smallest analyzed NCs. The magnitude of theblueshift is smaller than the emission line width, thus detectableonly by high-resolution PL mapping. By comparing the emission energiesobtained from the experiment and a rigorous effective mass model,we can fully attribute the observed variations to the size-dependentquantum confinement effect.

We report on the optical properties of a CsPbBr3 polycrystallinethin film on a single grain level. A sample composed of isolated nanocrystals(NCs) mimicking the properties of the polycrystalline thin film grainsthat can be individually probed by photoluminescence spectroscopywas prepared. These NCs were analyzed using correlative microscopyallowing the examination of structural, chemical, and optical propertiesfrom identical sites. Our results show that the stoichiometry of theCsPbBr(3) NCs is uniform and independent of the NCs'morphology. The photoluminescence (PL) peak emission wavelength isslightly dependent on the dimensions of NCs, with a blue shift upto 9 nm for the smallest analyzed NCs. The magnitude of theblueshift is smaller than the emission line width, thus detectableonly by high-resolution PL mapping. By comparing the emission energiesobtained from the experiment and a rigorous effective mass model,we can fully attribute the observed variations to the size-dependentquantum confinement effect.

We report on the optical properties of a CsPbBr3 polycrystallinethin film on a single grain level. A sample composed of isolated nanocrystals(NCs) mimicking the properties of the polycrystalline thin film grainsthat can be individually probed by photoluminescence spectroscopywas prepared. These NCs were analyzed using correlative microscopyallowing the examination of structural, chemical, and optical propertiesfrom identical sites. Our results show that the stoichiometry of theCsPbBr(3) NCs is uniform and independent of the NCs'morphology. The photoluminescence (PL) peak emission wavelength isslightly dependent on the dimensions of NCs, with a blue shift upto 9 nm for the smallest analyzed NCs. The magnitude of theblueshift is smaller than the emission line width, thus detectableonly by high-resolution PL mapping. By comparing the emission energiesobtained from the experiment and a rigorous effective mass model,we can fully attribute the observed variations to the size-dependentquantum confinement effect.