Residual Emission Research Articles

Revisiting the local interstellar radiation field using Gaia DR3

Context. Dust grains in the interstellar medium are heated by the integrated radiation from stars in the Milky Way. Thus, knowledge of the local interstellar radiation field (LISRF) is necessary to interpret observations of dust emission in the infrared and constrain (some) properties of interstellar grains. The LISRF representation that is most widely used in dust modeling still dates back to the seminal works of Mezger et al. (1982, A&A, 105, 372) and Mathis et al. (1983, A&A, 128, 212). Aims. A new version of the LISRF is presented here, starting from the photometry of the Gaia Data Release 3 (DR3) and revisiting the available data. This dataset includes observations from the Pioneer 10 and 11 probes. Methods. The LISRF contribution by direct starlight was estimated in the Gaia bands by summing fluxes of all stars in DR3. The LISRF was extrapolated from the optical to the ultraviolet and near-infrared, using the astrophysical parameters provided by DR3 for a subsample of Gaia stars. The correlation between dust emission at 100 µm and residual diffuse emission in the Pioneer and other available maps was exploited to derive the contribution of dust-scattered starlight to the LISRF. Results. The new LISRF is significantly redder and emits ~30% more energy than the old model. The old LISRF is almost a factor two lower in the near-infrared, while, in the optical, it accounts only for direct starlight. For |b| < 50°, diffuse starlight contributes on average to ~25% of the total radiation, which is three times more than what can be derived using literature estimates at high Galactic latitudes. Conclusions. The new LISRF can modify the predicted mid-infrared (MIR) dust emission beyond the uncertainties normally assumed between dust models and observational constraints. These differences should be taken into account to redefine the properties of small grains and of carriers of the MIR emission bands.

Different organic composts application in dryland Mollisol:Residual effect and soil CO2 emission.

Organic compost application plays an important role in improving the fertility of Mollisol. However, the effects of different organic composts on carbon sequestration varies greatly and its internal mechanism are unclear. We conducted a field experiment to explore the residual proportion of different organic composts and their effects on carbon emissions in dryland Mollisol in Northeast China. There were a total of seven treatments, including chemical fertilizer control (SNF), organic composts from cattle excreta (CRH), sheep excreta (SHP), chicken excreta (CKN), residue after corn starch production (BCS), residue with crop straws (HRS) and mushroom residue (WMC). We monitored annual soil CO2 flux by static chamber method, as well as the changes of environmental factors and soil dissolved carbon and nitrogen. The regulatory mechanism of organic component characteristics on carbon residual porprotion of organic composts were examined by neural network analysis. The results showed that compared with the SNF treatment, soil dissolved organic carbon (DOC) and extractable organic nitrogen increased by 26.3%-103.5% and 21.4%-150.0%, respectively. The aromaticity of soil DOC was significantly reduced. Heterotrophic respiration flux was mainly affected by soil temperature and DOC content, while its temperature sensitivity was significantly reduced in the CKN treatment. Annual accumulation of heterotrophic respiration increased from 203 g·C·m-2 of the control to 234-334 g·C·m-2 under treatments with organic composts applications, with the CKN and HRS treatments showing the strongest impact. The annual carbon residual proportion of different organic composts in Mollisol was in an order of CRH (91.2%)> WMC (82.9%)> BCS (82.6%)> SHP (78.1%)> CKN (70.2%)> HRS (69.3%). Hemicellulose content and C/N of organic composts were the key factors, which explained 58.8% and 32.9% of the total variations of carbon residual proportion. Organic compost from cattle excreta had higher residual proportion due to lower C/N, hemicellulose content and soluble polyphenol content, and thus did not significantly affect Mollisol heterotrophic respiration. Therefore, the application of organic compost from cattle excreta was more efficient to improve organic carbon in dryland Mollisol.

LANDFILL MINING IN THE FRAMEWORK OF INTEGRATED WASTE MANAGEMENT: CASE STUDY OF AN ITALIAN LANDFILL

A remediation project involving landfill mining (LFM) was designed and is ongoing at the 40-year-old Villadose landfill in Rovigo, Italy. The original natural clay lining the bottom of the old landfill is being recovered and used as technical material. Meanwhile newly constructed landfill sectors, designed to contained more than four times more waste than previously are being filled with both excavated waste and fresh municipal solid waste. A laboratory scale experiment was conducted to simulate the expected landfill conditions and analyse the effects of different waste fractions on emissions. The fresh municipal waste although pretreated at a mechanical biological treatment plant shows a significant residual emission potential, in terms of TOC, and NH4. A landfill housing such quality of waste would not be expected to have achieved final storage quality by the end of its aftercare life. The joint disposal of this waste fraction and the substantially degraded excavated waste may contribute to shortening this timeline. This paper reports the landfill mining operation, an assessment of the emissions from the landfill simulation reactors and the implications for the expected landfill behaviour.

Residual carbon emissions in companies’ climate pledges: who has to reduce and who gets to remove?

ABSTRACT Corporate carbon neutrality pledges have been criticized for their lack of integrity, especially when they are primarily based on the simple purchase of carbon offsets without making any significant emission reductions. Neutrality pledges that are consistent with the goal of the ISO corporate net zero guidelines should be based on the reduction of all but the so-called unavoidable or residual emissions. The residual emissions should be neutralized not through reduction offsets but by actually removing the equivalent amount of emissions from the atmosphere. In this paper, I analyze whether climate pledges of 115 large companies, which cover all eleven Global Industry Classification Standards’ sectors, follow the aforementioned net zero definition. The assessed criteria are (i) the type of pledge made, (ii) the definition of residual emissions employed and (iii) whether the company commits to neutralize its emissions exclusively with removals. Secondly, the assessment involves evaluating the companies’ commitment to their net zero pledges by examining the residual emission level provided and determining if their climate goal extends to absolute scope 3 emissions. From the companies that had a net zero target (69) only 22% aimed to reduce emissions to a residual level and compensate with removals. The residual emission levels in the target year is specified by 29 companies and ranges between 0 and 80% (mean = 19.3%, median = 10%, n = 29). More than half of the residual emissions that exceed the median of 10% are claimed by sectors that are not classified as hard-to-abate such as information technology or communication companies.

68‐3: Distinguished Paper: A 4.7 inch 650 PPI AM‐QLED Display Prepared by Direct Photolithography

In this work, efficient QD‐photosensitive ligand system were designed. By direct photolithography, RGB pixel arrays with a single sub‐pixel size of 39 um × 5 um were successfully prepared on patterned PM substrates. While illuminated separately, there were no residual QD emission peaks from neighbor sub‐pixel in electroluminescence spectra. Experience on the PM substrate guided the successful preparation of a 4.7‐inch 650 ppi AM‐QLED display. This was the first AM‐QLED prototype prepared by direct lithography.

Experimental study of an improved pulse-jet cleaning method to enhance performance of cartridge dust collectors

In the field of industrial dedusting, incomplete cartridge cleaning and excessive pressure drop are main problems faced by cartridge dust collectors. The conventional way of cleaning dust accumulated on a cartridge is to spray pulsed airstream from a nozzle installed at the top of cartridge. However, this method has limited effect on sticky or moist dust. This article experimentally investigates the pulse-jet cleaning effect of a double-nozzle system arranged at the bottom and top of the cartridge respectively. Results show that the cleaning effect of the double-nozzle system was much better than that of the conventional single-nozzle system. At 0.3 MPa tank pressure, the mean residual pressure drop and dust emission concentration in the top-bottom simultaneous cleaning mode using double-nozzle system decreased by 24.32% and 12.91% respectively, compared with those in the top-only cleaning mode. At higher tank pressures (> 0.5 MPa), the top-bottom successive cleaning mode exhibited better effects.

A 4.7‐inch 650 PPI AMQLED display prepared by direct photolithography

AbstractIn this work, a highly efficient photosensitive quantum dot (QD) system was designed. The optimized photosensitive QD system had high photoluminescence quantum yield and colloidal stability. By direct photolithography, RGB pixel arrays with a single sub‐pixel size of 39 μm × 5 μm were successfully prepared. Further, the full‐color QLED device was realized. There were no residual QD emission peaks from neighboring sub‐pixels observed in the electroluminescence spectra. Experience on the full‐color QLED device guided the successful preparation of a 4.7‐inch 650 PPI active matrix QLED prototype. The active matrix QLED prototype could display clear and complete pictures. The color gamut reached 85% of the BT2020 standard. This is the first active matrix QLED prototype prepared with a record‐high resolution by direct photolithography, which promoted the development of QLED display technology.

One Health-based management for sustainably mitigating tetracycline-resistant Aeromonas hydrophila-induced health risk

Aeromonas hydrophila has ability to spread tetracycline resistance (tetR) under stresses of oxytetracycline (OTC), one of the most important antibiotics in aquaculture industry. Even though environmental reservoir of Aeromonas allows it to be at interfaces across One Health components, a robust modelling framework for rigorously assessing health risks is currently lacking. We proposed a One Health-based approach and leveraged recent advances in quantitative microbial risk assessment appraised by available dataset to interpret interactions at the human–animal–environment interfaces in various exposure scenarios. The dose–response models were constructed considering the effects on mortality for aquaculture species and tetR genes transfer for humans. A scenario-specific risk assessment on pond species-associated A. hydrophila infection and human gut-associated tetR genes transfer was examined. Risk-based control strategies were involved to test their effectiveness. We showed that farmed shrimp exposed to tetracycline-resistant A. hydrophila in OTC-contaminated water experienced higher infection risk (relative risk: 1.25–1.34). The tetR genes transfer risk for farmers in shrimp ponds (∼2 × 10−4) and swimmers in coastal areas (∼4 × 10−6) during autumn exceeded acceptable risk (10−6). This cautionary finding underscores the importance of accounting for monitoring, assessing, and mitigating occupational health hazards among workers in shrimp farming sectors within future One Health-based strategies for managing water infection risks. We recommend that OTC emission rate together with A. hydrophila concentration should be reduced by up to 70–99% to protect human, farmed shrimp, and environmental health. Our predictive framework can be adopted for other systems and be used as a “risk detector” for assessing tetR-related health risks that invoke potential risk management on addressing sustainable mitigation on offsetting residual OTC emission and tetR genes spread in a species–human–environmental health system.

Using Irradiation-Acquisition Interleaved Time-Integrated Imaging to Assess Delayed Luminescence and the Noise-Laden Residual Spontaneous Photon Emission of Yeast

Delayed luminescence from organisms informs oxidative stress that may be modulable by external stimulations. In the absence of external stress causing delayed luminescence, organisms may produce spontaneous ultraweak photon emission due to the residual oxygen demand. To better understand the oxidative state of an organism, it is desirable to acquire the delayed luminescence to reach the phase wherein the ultraweak photon emission resides. This, however, is challenging due to the significant difference in the order of magnitude of the photon counts between the two types of photon emission. Conventional time-gated measurement requires a high dynamic range to assess the noise-level photon emission, whereas simple long exposure can miss the kinetics of luminescence. There may be a compromise to be made between robustly acquiring the decay kinetics of the delayed luminescence and reliably acquiring the noise-laden spontaneous photon emission. We demonstrate an irradiation-acquisition interleaved time-integrated imaging approach that may enable the reliable acquisition of slow-decay delayed luminescence down to the level of ultraweak photon emission. Repetitive irradiation was interleaved with a gradually increased time of acquisition to assess the integrated time course of the post-irradiation luminescence. Such instrument configuration performed on yeast facilitated the use of time differentiation to assess the delayed luminescence down to the noise-level ultraweak photon emission at the expense of the total time of acquisition.

Heritability estimates and genome-wide association study of methane emission traits in Nellore cattle.

The objectives of the present study were to estimate the heritability for daily methane emission (CH4) and residual daily methane emission (CH4res) in Nellore cattle, as well as to perform genome-wide association studies (GWAS) to identify genomic regions and candidate genes influencing the genetic variation of CH4 and CH4res. Methane emission phenotypes of 743 Nellore animals belonging to 3 breeding programs were evaluated. CH4 was measured using the sulfur hexafluoride (SF6) tracer technique (which involves an SF6 permeation tube introduced into the rumen, and an appropriate apparatus on each animal), and CH4res was obtained as the difference between observed CH4 and CH4 adjusted for dry matter intake. A total of 6,252 genotyped individuals were used for genomic analyses. Data were analyzed with a univariate animal model by the single-step GBLUP method using the average information restricted maximum likelihood (AIREML) algorithm. The effects of single nucleotide polymorphisms (SNPs) were obtained using a single-step GWAS approach. Candidate genes were identified based on genomic windows associated with quantitative trait loci (QTLs) related to the 2 traits. Annotation of QTLs and identification of candidate genes were based on the initial and final coordinates of each genomic window considering the bovine genome ARS-UCD1.2 assembly. Heritability estimates were of moderate to high magnitude, being 0.42 ± 0.09 for CH4 and 0.21 ± 0.09 for CH4res, indicating that these traits will respond rapidly to genetic selection. GWAS revealed 11 and 15 SNPs that were significantly associated (P < 10-6) with genetic variation of CH4 and CH4res, respectively. QTLs associated with feed efficiency, residual feed intake, body weight, and height overlapped with significant markers for the traits evaluated. Ten candidate genes were present in the regions of significant SNPs; 3 were associated with CH4 and 7 with CH4res. The identified genes are related to different functions such as modulation of the rumen microbiota, fatty acid production, and lipid metabolism. CH4 and CH4res presented sufficient genetic variation and may respond rapidly to selection. Therefore, these traits can be included in animal breeding programs aimed at reducing enteric methane emissions across generations.

Effect of residual methane emission on physiological characteristics and carcass performance in Japanese Black cattle.

This study investigated the physiological characteristics and carcass performance associated with residual methane emissions (RME), and the effects of bull differences on CH4-related traits in Japanese Black cattle. Enteric methane (CH4) emissions from 156 Japanese Black cattle (111 heifers and 45 steers) were measured during early fattening using the sniffer method. Various physiological parameters were investigated to clarify the physiological traits between the high, middle, and low RME groups. CH4-related traits were examined to determine whether bull differences affected progeny CH4 emissions. Ruminal butyrate and NH3 concentrations were significantly higher in the high-RME group than in the low-RME group, whereas the propionate content was significantly higher in the low-RME group. Blood urea nitrogen, β-hydroxybutyric acid, and insulin concentrations were significantly higher, and blood amino acids were lower in the high-RME group than in the other groups. No significant differences were observed in the carcass traits and beef fat composition between RME groups. CH4-related traits were significantly different among bull herds. Our results show that CH4-related traits are heritable, wherein bull differences affect progeny CH4 production capability, and that the above-mentioned rumen fermentations and blood metabolites could be used to evaluate enteric methanogenesis in Japanese Black cattle.

Instantaneous CO2 emission modelling for a Euro 6 start-stop vehicle based on portable emission measurement system data and artificial intelligence methods

One of the increasingly common methods to counteract the increased fuel consumption of vehicles is start-stop technology. This paper introduces a methodology which presents the process of measuring and creating a computational model of CO2 emissions using artificial intelligence techniques for a vehicle equipped with start-stop technology. The method requires only measurement data of velocity, acceleration of vehicle, and gradient of road to predict the emission of CO2. In this paper, three methods of machine learning techniques were analyzed, while the best prediction results are shown by the gradient boosting method. For the developed models, the results were validated using the coefficient of determination, the mean squared error, and based on visual evaluation of residual and instantaneous emission plots and CO2 emission maps. The developed models present a novel methodology and can be used for microscale environmental analysis.

Residual methane emissions in grazing lactating dairy cows

ABSTRACT Residual methane emission (RME) is a trait that has previously been identified as being independent of animal production traits. The objective of this study was to investigate the effect of ranking grazing dairy cows by RME on animal productivity and enteric methane (CH4) emissions. Milk production, dry matter intake (DMI), liveweight (LWT) and CH4 were recorded on grazing late lactation dairy cows at Teagasc Moorepark, Ireland. The dairy cows were producing 352 g CH4/day, while consuming 16.6 kg DM. The mean methane yield was 20.79 g CH4/kg DMI. Residual methane emission was calculated as the difference between measured CH4 yield and New Zealand emission factor (21.6 g CH4/kg DMI). These dairy cows were ranked based on their RME and classified into groups. The low RME group produced 15% less CH4 than the high RME group while maintaining milk production and feed conversion efficiency. The low RME group had lower methane yield, and methane intensity. There are no significant phenotypic correlations between RME and animal production traits such as energy corrected milk yield, or LWT. These results indicate that RME has the ability to select and rank low emitting grazing dairy cows while being independent from animal productivity traits.

New detailed characterization of the residual luminescence emitted by the GAGG:Ce scintillator crystals for the HERMES Pathfinder mission

The HERMES (High Energy Rapid Modular Ensemble of Satellites) Pathfinder mission aims to develop a constellation of nanosatellites to study astronomical transient sources, such as gamma-ray bursts, in the X and soft γ energy range, exploiting a novel inorganic scintillator. This study presents the results obtained describing, with an empirical model, the unusually intense and long-lasting residual emission of the GAGG:Ce scintillating crystal after irradiating it with high energy protons (70 MeV) and ultraviolet light (∼ 300 nm). From the model so derived, the consequences of this residual luminescence for the detector performance in operational conditions has been analysed. The suitability of this detector for the HERMES Pathfinder nanosatellites was demonstrated by the low contribution of the afterglow, 1–2 pA at peak, to the input current of the front-end electronics.

Technology to the rescue? Techno-scientific practices in the United Kingdom Net Zero Strategy and their role in locking in high energy decarbonisation pathways

The development of country specific decarbonisation pathways is becoming increasingly common as more governments commit to achieving Net Zero. These pathways are critical for setting the direction and pace of decarbonisation.This article reviews the characteristics of fifteen different UK Net Zero pathways (three government pathways and 12 additional pathways) and shows how the expectation of technology innovation and low-carbon energy abundance closes down the space potential pathways can occupy. In particular, we find that while conceptually different, the three government pathways display a high degree of similarity and that the majority of pathways rely on significant amounts of new clean energy and retain large residual emissions in 2050 which requires the deployment of significant new carbon dioxide removal technologies.The dominance of high energy and high residual emission pathways is also observed in international scenarios including IPCC's Shared Socioeconomic Baseline Pathways and the IEA's Net Zero Energy Scenario. By situating these domestic plans within an international context, the paper explores how the reliance on new technology in developed countries perpetuates an unjust model of fossil-fuelled development and blocks the development of alternative, transformative decarbonisation pathways from being considered.

Comparative analysis of decarbonising economy in Siberia and Scandinavia megaregions: Price, value and values of energy

The climate change and deterioration of nature appear to be global problems, and the efficiency of solving them depends on the level of decarbonizing countries’ and regions’ economies. Siberia and Scandinavia are relevant megaregions with similar natural, climate, economic and energy characteristics, though demonstrat­ing, in many cases, different patterns of decarbonizing. The accomplished compara­tive analysis has confirmed that the differences have been conditioned by different approaches to the process of decarbonization. Low-carbon vector of Siberia suggests counterbalance of total GHG, owing to CO2 reduction and its removal with purpose to achieve carbon-neutrality by 2060. In Scandinavia reaching net-zero emission by 2050 suggests the compensation of only residual emission of GHG and only thanks to reliable removal and sequestration technologies. Differences depend on prices and values that refer to the energy sector as a prime emitter in both megaregions. In Siberia the focus is on the evolutionary, gradual energy transition from coal to natural gas, considering that fossil fuels are cheap, available, subsidized by state, and supported by the modernization activities of energy companies, which are led by principals of security, stability and profitability. Scandinavia megaregion seems to prefer the approach to electrifying economy with renewables. Such choice has been determined not only by the price-fall of renewables, but also by the growth of their value on behalf of long-term, innovative activities of energy companies, active role of the states with the purpose of reaching the common good.

A comparison of methods to balance geophysical flows

We compare a higher-order asymptotic construction for balance in geophysical flows with the method of ‘optimal balance’, a purely numerical approach to separating inertia–gravity waves from vortical modes. Both methods augment the linear geostrophic mode with dependent inertia–gravity wave mode contributions, the so-called slaved modes, such that the resulting approximately balanced states are characterized by very small residual wave emission during subsequent time evolution. In our benchmark setting – the single-layer rotating shallow water equations in the quasi-geostrophic regime – the performance of both methods is comparable across a range of Rossby numbers and for different initial conditions. Cross-balancing, i.e. balancing the model with one method and diagnosing the imbalance with the other, suggests that both methods find approximately the same balanced state. Our results also reinforce results from previous studies suggesting that spontaneous wave emission from balanced flow is very small. We further compare two numerical implementations of each of the methods: one pseudospectral, and the other a finite difference scheme on the standard C-grid. We find that a state that is balanced relative to one numerical scheme is poorly balanced for the other, independent of the method that was used for balancing. This shows that the notion of balance in the discrete case is fundamentally tied to a particular scheme.

Effect of stacking sequence and thickness variation on the thermo-mechanical properties of flax-kenaf laminated biocomposites and prediction of the optimal configuration using a decision-making framework

Abstract The use of naturally derived eco-friendly biocomposites became more popular due to growing environmental concerns and hunt for sustainable materials. Biocomposites can reduce the residual waste and carbon emission to the environment during their lifecycle. The present study aims to develop biocomposites by reinforcing flax fiber (F) and kenaf fiber (K) laminates with bio-epoxy matrix at four different arrangements (FFF, FKF, KFK, and KKK). The biocomposite samples were fabricated with three laminated thicknesses (3 mm, 4 mm and 5 mm) and the thermo-mechanical performance was investigated. The results showed that FFF biocomposites recorded higher tensile, flexural, and interfacial properties with lower density and absorption of water compared to KKK biocomposites due to higher cylindrical lumen diameter of flax laminates. The hybridization of flax with kenaf fiber at different stacking sequences provided greater strength, modulus, toughness, stiffness, thermal stability and degradation behaviour due to greater interfacial interaction between laminated fiber and bio-epoxy. The FKF biocomposites showed maximum impact strength (52.96 kJ/m2), tensile strength (110.21 MPa), and compressive strength (139.64 MPa) at 5 mm laminated thickness while, flexural (158.67 MPa) and shear strength (39.45 MPa) were maximum at 4 mm thickness with the highest degradation temperature (336 °C). The optimal biocomposite configuration has been identified through employability of a novel decision-making framework encompassing interval-valued intuitionistic fuzzy sets, TOmada de DecisaoInterativaMulticriterio (TODIM) and Schweizer–Sklar operations. The inclusive evaluation with regard to the applied framework has revealed that FKF and KFK biocomposites with 4 mm thickness (Lam5 and Lam8) configuration to have the optimal configuration. On the other hand, Lam 10, i.e., KKK_3 mm turned out to be inferior to all the considered biocomposite configurations.

Bright single-photon emission from a GeV center in diamond under a microfabricated solid immersion lens at room temperature

We report on the metrological characterization of the emission from a germanium-vacancy center in diamond under a microfabricated solid immersion lens in a confocal laser-scanning microscope setup. Ge ions were implanted into a synthetic diamond at 3 MeV, and germanium-vacancy centers were then formed by subsequent annealing. Afterward, solid immersion lenses were fabricated in a focused ion beam scanning electron microscope. The photoluminescence was investigated at room temperature in terms of the spectral distribution, the excited state lifetime, the second-order correlation function, and the saturation behavior, proving simultaneous high single-photon purity and high brightness. Two methods were exploited to minimize the residual multi-photon probability: spectral filtering and temporal filtering. According to these results, we assume that Raman scattered photons and emission from neighboring color centers play an important role in the residual multi-photon emission probability. The system efficiency of the single-photon source was investigated and found to be in accordance with the value calculated from all sources of loss in the setup. The branching ratio of the germanium-vacancy center for the decay into the ground state and into metastable state was calculated. The results enable the usage of the single-photon source in future quantum radiometric experiments.

Up-converted photorefractive optical transient detection with femtosecond laser pulses.

We report on experimental demonstration of optical transient detection (OTD) based on photorefractive two-wave mixing of femtosecond pulses. The demonstrated technique also combines nonlinear-crystal-based OTD with up-conversion from infrared into the visible range. The approach enables measurement of phase changes of a dynamic signal in the infrared using GaP- or Si-based detectors while suppressing stationary background. Experimental results reveal existence of the relation between input phases in the infrared and output phases in the visible wavelength range. We further present experimental evidence of additional merits of up-converted transient phase analysis under noisy conditions, such as residual continuous-wave emission affecting the ultrashort pulses from the laser.