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Cheap and sensitive gamma-ray detectors are desired for defence, medical and research applications. Solid-state gamma-radiation detectors made from solution-grown perovskites have now been demonstrated for multiple practical applications. The decay of the majority of radioactive isotopes involves the emission of gamma (γ) photons with energies of ∼50 keV to 10 MeV. Detectors of such hard radiation that are low-cost, highly sensitive and operate at ambient temperatures are desired for numerous applications in defence and medicine, as well as in research 1 , 2 . We demonstrate that 0.3–1 cm solution-grown single crystals (SCs) of semiconducting hybrid lead halide perovskites (MAPbI 3 , FAPbI 3 and I-treated MAPbBr 3 , where MA = methylammonium and FA = formamidinium) can serve as solid-state gamma-detecting materials. This possibility arises from a high charge-carrier mobility–lifetime ( μτ ) product of 1.0–1.8 × 10 −2  cm 2  V −1 , a low dark carrier density of 10 9 –10 11 cm −3 (refs  3 , 4 ), a low density of charge traps of 10 9 –10 10  cm −3 (refs  4 , 5 ) and a high absorptivity of hard radiation by the lead and iodine atoms. We demonstrate the utility of perovskite detectors for testing the radiopurity of medical radiotracer compounds such as 18 F-fallypride. Energy-resolved sensing at room temperature is presented using FAPbI 3 SCs and an 241 Am source.

Our world is subject to various kinds of pollution and contamination due to rapid growth and development of industrialization. Though, industries are helping to improve the human life style in many ways in day to day life such as power generation to treatment of diseases. At the same time, industries emit the waste which causes major environmental pollution and leads to harmful for all living organism. As the renewable energy sources are depleting, energy/power generation become a major research around the world. Nuclear energy is one of the promising energy to sort out the energy demand, but the problem associated with the nuclear energy is the management and treatment of radioactive waste/emission/effluent since which is more dangerous to all living organism. There is a large scale contamination of radioactive waste associated for the past 60 years of global nuclear activity. It is necessary to pay special attention to the management of radioactive wastes in order to approach pollution-free environment and avoid diseases to living organism through various clean-up strategies. In this review, we discussed the wide ranges of strategies available for radioactive waste management such as physical, chemical, and biological methods. Bioremediation may be the powerful tool for treatment of radioactive wastes. Additionally, discussed on recent advancement have been made in treatment of radioactive waste through microbial transformation as well as phytoremediation which play a major role in disposal of radioactive waste.

We present an application of multi-isotopic fingerprints (i.e., 236 U/ 238 U, 233 U/ 236 U, 236 U/ 129 I and 129 I/ 127 I) for the discovery of previously unrecognized sources of anthropogenic radioactivity. Our data indicate a source of reactor 236 U in the Baltic Sea in addition to inputs from the two European reprocessing plants and global fallout. This additional reactor 236 U may come from unreported discharges from Swedish nuclear research facilities as supported by high 236 U levels in sediment nearby Studsvik, or from accidental leakages of spent nuclear fuel disposed on the Baltic seafloor, either reported or unreported. Such leakages would indicate problems with the radiological safety of seafloor disposal, and may be accompanied by releases of other radionuclides. The results demonstrate the high sensitivity of multi-isotopic tracer systems, especially the 233 U/ 236 U signature, to distinguish environmental emissions of unrevealed radioactive releases for nuclear safeguards, emergency preparedness and environmental tracer studies. Anthropogenic activities lead to the accumulation of radioactive substances in the environment. Here the authors use multi-isotopic fingerprints of uranium and iodine to discover a previously unknown source of reactor uranium in the Baltic Sea, likely sourced from a Swedish nuclear facility.

Radiocarbon analyses are commonly used in a broad range of fields, including earth science, archaeology, forgery detection, isotope forensics, and physiology. Many applications are sensitive to the radiocarbon (14C) content of atmospheric CO₂, which has varied since 1890 as a result of nuclear weapons testing, fossil fuel emissions, and CO₂ cycling between atmospheric, oceanic, and terrestrial carbon reservoirs. Over this century, the ratio14C/C in atmospheric CO₂ (Δ14CO₂) will be determined by the amount of fossil fuel combustion, which decreases Δ14CO₂ because fossil fuels have lost all14C from radioactive decay. Simulations of Δ14CO₂ using the emission scenarios from the Intergovernmental Panel on Climate Change Fifth Assessment Report, the Representative Concentration Pathways, indicate that ambitious emission reductions could sustain Δ14CO₂ near the preindustrial level of 0‰ through 2100, whereas “business-as-usual” emissions will reduce Δ14CO₂ to −250‰, equivalent to the depletion expected from over 2,000 y of radioactive decay. Given current emissions trends, fossil fuel emission-driven artificial “aging” of the atmosphere is likely to occur much faster and with a larger magnitude than previously expected. This finding has strong and as yet unrecognized implications for many applications of radiocarbon in various fields, and it implies that radiocarbon dating may no longer provide definitive ages for samples up to 2,000 y old.

In the beginning of April 2020, large fires that started in the Chernobyl Exclusion Zone (CEZ) established after the Chernobyl accident in 1986 caused media and public concerns about the health impact from the resuspended radioactivity. In this paper, the emissions of previously deposited radionuclides from these fires are assessed and their dispersion and impact on the population is examined relying on the most recent data on radioactive contamination and emission factors combined with satellite observations. About 341 GBq of 137Cs, 51 GBq of 90Sr, 2 GBq of 238Pu, 33 MBq of 239Pu, 66 MBq of 240Pu and 504 MBq of 241Am were released in 1st–22nd April 2020 or about 1,000,000,000 times lower than the original accident in 1986 and mostly distributed in Central and East Europe. The large size of biomass burning particles carrying radionuclides prevents long-range transport as confirmed by concentrations reported in Europe. The highest cumulative effective doses (> 15 μSv) were calculated for firefighters and the population living in the CEZ, while doses were much lower in Kiev (2–5 μSv) and negligible in Belarus, Russia and Europe. All doses are radiologically insignificant and no health impact o

Isotopic ratios of radioactive releases into the environment are useful signatures for contamination source assessment. Uranium is known to behave conservatively in sea water so that a ratio of uranium trace isotopes may serve as a superior oceanographic tracer. Here we present data on the atomic 233 U/ 236 U ratio analyzed in representative environmental samples finding ratios of (0.1–3.7) ⋅ 10 − 2 . The ratios detected in compartments of the environment affected by releases of nuclear power production or by weapons fallout differ by one order of magnitude. Significant amounts of 233 U were only released in nuclear weapons fallout, either produced by fast neutron reactions or directly by 233 U-fueled devices. This makes the 233 U/ 236 U ratio a promising new fingerprint for radioactive emissions. Our findings indicate a higher release of 233 U by nuclear weapons tests before the maximum of global fallout in 1963, setting constraints on the design of the nuclear weapons employed. The dominant emission sources of anthropogenic radionuclides come from either atmospheric nuclear weapons tests or the nuclear industry (i.e., reprocessing plants or reactor accidents). Here, the authors identify a new environmental isotope tracer ( 233 U/ 236 U) which can help distinguish emissions from nuclear weapons tests, and can also provide constraints on past weapon designs and fuel sources, for which many details remain classified or lost.

The utilization of nuclear power will persist as a prominent energy source in the foreseeable future. However, it presents substantial challenges concerning waste disposal and the potential emission of untreated radioactive substances, such as radioactive 129I and 131I. The transportation of radioactive iodine poses a significant threat to both the environment and human health. Nevertheless, effectively, rapidly removing iodine ion from water using porous adsorbents remains a crucial challenge. In this work, three kinds of multiple sites porous organic polymers (POPs, POP-1, POP-2, and POP-3) have been developed using a monomer pre-modification strategy for highly efficient and fast I3− absorption from water. It is found that the POPs exhibited exceptional performance in terms of I3− adsorption, achieving a top-performing adsorption capacity of 5.25 g g−1 and the fastest average adsorption rate (K80% = 4.25 g g−1 h−1) with POP-1. Moreover, POP-1 exhibited exceptional capacity for the removal of I3− from flowing aqueous solutions, with 95% removal efficiency observed even at 0.0005 mol L−1. Such results indicate that this material has the potential to be utilized for the emergency preparation of potable water in areas contaminated with radioactive iodine. The adsorption process can be effectively characterized by the Freundlich model and the pseudo-second-order model. The exceptional I3− absorption capacity is primarily attributed to the incorporation of a substantial number of active adsorption sites, including bromine, carbonyl, and amide groups. The porous organic polymer adsorbent demonstrated outstanding performance in I3-adsorption, achieving an exceptional adsorption capacity, the highest average adsorption rate, and notable low-concentration adsorption efficiency. [Display omitted] •Multiple sites POPs were prepared by monomer pre-modification strategy.•POP-1 exhibit a top-performing adsorption capacity of 5.25 g g−1•POP-1 has a fastest average adsorption rate (K80 % = 4.25 g g−1 h−1).•Multiple sites cooperative interactions of I3− with the groups in POPs is the adsorption mechanism.

We review current understanding of kilonova/macronova emission from compact binary mergers (mergers of two neutron stars or a neutron star and a black hole). Kilonova/macronova is emission powered by radioactive decays of r -process nuclei and it is one of the most promising electromagnetic counterparts of gravitational wave sources. Emission from the dynamical ejecta of ~0.01 M ⊙ is likely to have a luminosity of ~1040–1041 erg s−1 with a characteristic timescale of about 1 week. The spectral peak is located in red optical or near-infrared wavelengths. A subsequent accretion disk wind may provide an additional luminosity or an earlier/bluer emission if it is not absorbed by the precedent dynamical ejecta. The detection of near-infrared excess in short GRB 130603B and possible optical excess in GRB 060614 supports the concept of the kilonova/macronova scenario. At 200 Mpc distance, a typical peak brightness of kilonova/macronova with 0.01 M ⊙ ejecta is about 22 mag and the emission rapidly fades to >24 mag within ~10 days. Kilonova/macronova candidates can be distinguished from supernovae by (1) the faster time evolution, (2) fainter absolute magnitudes, and (3) redder colors. Since the high expansion velocity ( v ~ 0.1 – 0.2 c ) is a robust outcome of compact binary mergers, the detection of smooth spectra will be the smoking gun to conclusively identify the gravitational wave source.

Supernova 2018ibb of the PISN category, related to the dynamical instability of oxygen core in a supermassive star induced by pair-creation shows at the nebular stage strong [O III] emission lines of an uncertain origin. I propose a simple model that demonstrates a possibility of [O III] lines emission from the supernova oxygen matter ionized and heated by the Co radioactive decay. The reason is pinpointed by which the [O III] line luminosity among supernovae of PISN category can vary in a broad range.

Purpose Weighting in LCA is important as it supports decision-making by prioritising and determining which impact categories are more important. However, the lack of weighting factors in developing countries forces LCA practitioners to adopt weighting values developed for other countries, leading to a less transparent decision-making process. One transparent and easily reproducible distance-to-target (DtT) weighting method that can be applied in Nigeria is the Swiss-developed ecological scarcity method. This method is based on the ratio of the current environmental situation of a country, region or product to the desired policy targets. The purpose of this study was to apply the ESM to develop weighting factors and eco-factors for Nigeria. Methods The normalization and current flows data for emissions and resource use in 2010 (base year) were collected from official data sources, and the critical flows were extracted from corresponding policy targets of the Government of Nigeria in 2030 (target year). The ESM was then applied to the aggregated data to derive Nigeria-specific weighting factors and eco-factors as the quantitative indicators for the emissions and resources. Results and discussion Weighting and eco-factors for emissions and resources were developed for 25 environmental issues in Nigeria. NOx, total petroleum hydrocarbon and land use weigh heavily. Except for carcinogenic substances in the air, emissions to water resulted in high eco-factors: TPH, phenol, total nitrogen, nitrate, ammonia and heavy metals (human and ecotoxicity). Policymakers in Nigeria need to set quantitative emission reduction targets for substances and such as carcinogenic substances in the air, oil spills and metal mineral resources. Conclusions The ESM was used to develop Nigeria’s eco-factors as quantitative indicators for emissions or resource use using the normalization and current flows in 2010 obtained from government data sources as base year data. The critical flows were extracted from the policy targets of the government of Nigeria, with 2030 as the target year. The eco-factors can support environmental sustainability decision-making in Nigeria. Future methodological development should apply updated policy targets and more data to calculate eco-factors for missing substances such as waste (radioactive and non-radioactive), heavy metal emissions to air and soil, emissions to groundwater, photochemical ozone creation substances and phosphorous in surface water and soil.