chemical pollution
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Universe ◽  
2022 ◽  
Vol 8 (1) ◽  
pp. 44
Author(s):  
Mario Cirillo ◽  
Luciano Piersanti ◽  
Oscar Straniero

Little is known about the first stars, but hints on this stellar population can be derived from the peculiar chemical composition of the most metal-poor objects in the Milky Way and in resolved stellar populations of nearby galaxies. In this paper, we review the evolution and nucleosynthesis of metal-poor and extremely metal-poor (EMP) stars with low and intermediate masses. In particular, new models of 6 M⊙ with three different levels of metallicity, namely Z=10−4, 10−6 and 10−10, are presented. In addition, we illustrate the results obtained for a 2 M⊙, Z=10−5 model. All these models have been computed by means of the latest version of the FuNS code. We adopted a fully coupled scheme of solutions for the complete set of differential equations describing the evolution of the physical structure and the chemical abundances, as modified by nuclear processes and convective mixing. The scarcity of CNO in the material from which these stars formed significantly affects their evolution, their final fate and their contribution to the chemical pollution of the ISM in primordial galaxies. We show the potential of these models for the interpretation of the composition of EMP stars, with particular emphasis on CEMP stars.


2022 ◽  
Vol 103 (1) ◽  
Author(s):  
Erin S. McCallum ◽  
Cody J. Dey ◽  
Daniel Cerveny ◽  
Aneesh P. H. Bose ◽  
Tomas Brodin
Keyword(s):  

2022 ◽  
Vol 174 ◽  
pp. 113230
Author(s):  
Jefferson R. Souza ◽  
Luiz Henrique Sielski ◽  
Maiara Krause ◽  
Brenda Silva Souza ◽  
Geisamanda Pedrini Brandão ◽  
...  
Keyword(s):  

2021 ◽  
Vol 64 (11) ◽  
pp. 839-845
Author(s):  
V. P. Meshalkin ◽  
O. B. Butusov ◽  
V. G. Dovi ◽  
A. Yu. Belozerskii ◽  
V. V. Chelnokov

The considered operating ferrous metallurgy enterprise uses three different technological modes of steel smelting, each of which is characterized by an individual composition of the ingredients of chemical pollutant emissions into the atmosphere affecting the state of the forest areas around this enterprise. Based on the decoding of satellite pixel photographs of forest areas, the technological mode with the least impact on forest areas was determined. It corresponds to the condition of the minimum area of ecological zones around the ferrous metallurgy enterprise. The authors propose an assessment of the impact of chemical pollution of ferrous metallurgy enterprises on forests in the form of areas of ecological zones of the state of forest vegetation and the volume of biomass in its various parts. The mosaic of ecological zones of forest areas is determined from their satellite pixel photographs using an original algorithm of “controlled cluster analysis”. The main recommendation for ferrous metallurgy enterprises to choose one of several alternative technological modes is as follows: the choice of technological mode should be based on a comparison of sizes of the areas of ecological zones. In this case, the technological mode with the smallest dimensions of the area is selected. Assessment of the damage caused by the chemical pollution of the plant to forest areas was determined by the area of ecological zones and the volume of biomass loss in forest areas in comparison with the background areas. The boundaries of ecological zones can be determined according to the “dose-effect” dependencies typical for the considered region.


2021 ◽  
Vol 10 (1) ◽  
Author(s):  
Dakis-Yaoba Ouédraogo ◽  
Olivier Perceval ◽  
Christine Ferrier-Pagès ◽  
Isabelle Domart-Coulon ◽  
Laetitia Hédouin ◽  
...  

Abstract Background Tropical coral reefs cover only ca. 0.1% of the Earth’s surface but host an outstanding biodiversity and provide important ecosystem services to millions of people living nearby. They are currently threatened by global (e.g., climate change) and local (e.g., chemical pollution) stressors that interact in different ways. While global stressors cannot be mitigated by local actions alone, local stressors can be reduced through ecosystem management. A systematic map on the impacts of chemicals arising from anthropogenic activities on tropical reef-building corals, which are the main engineer species of reef ecosystems, was published in 2021. This systematic map gathered an abundant literature (908 articles corresponding to 7937 studies), and identified four well-represented subtopics, amenable to relevant full syntheses. Here, we focused on one of the four subtopics: we aimed to systematically review the evidence on the ecotoxicological effects of chemicals on tropical reef-building corals. Methods The evidence will be identified from the recent systematic map on the impacts of chemicals arising from anthropogenic activities on tropical reef-building corals. Especially, all studies in the map database corresponding to the knowledge cluster “evidence on the ecotoxicological effects of chemicals on corals” will be selected. To identify the evidence produced since then, a search update will be performed using a subset of the search string used for the systematic map, and titles, abstracts and full-texts will be screened according to the criteria defining the selected cluster of the map. In addition, as the eligibility criteria for the systematic review are narrower than those used to define the cluster in the systematic map, additional screening will be carried out. The included studies will then be critically appraised and a low, medium, or high risk of bias will be assigned to each study. Data will be extracted from studies and synthesised according to a strategy depending on the type of exposure and outcome. Synthesis will be mainly quantitative but also narrative, aiming to identify toxicity thresholds of chemicals for corals.


2021 ◽  
Author(s):  
MM Saltykova ◽  
IP Bobrovnitskiy ◽  
AV Balakaeva

Increasing use of ionizing radiation sources in different spheres of human life dictates the need for investigating the effects of low-dose radiation on mortality and morbidity. The aim of this study was to compare mortality from the most common non-communicable diseases in the cities of Severodvinsk and Arkhangelsk. We analyzed the rates of age- and sex-specific mortality from circulatory system diseases (CSD), malignancies, digestive system disorders, respiratory system diseases, and external causes. CSD-related mortality among men and women past working age was higher in Severodvinsk than in Arkhangelsk (median (Q1; Q3): 3,349 (3,271; 3,458) vs 2,651 (2,618; 2,756), p < 0.012; 1,947 (1,890; 2,022) vs 1,753 (1,727; 1,809), p < 0.012; 292 (281; 342) vs 265 (253; 274), p < 0.025, respectively). For other causes of death, mortality rates in Severodvinsk did not exceed those in Arkhangelsk. Increased mortality from CSD in Severodvinsk cannot be linked to socioeconomic conditions or chemical air pollution because the standard of living is higher in Severodvinsk than in Arkhangelsk, whereas the level of chemical pollution is lower. At the same time, the presence of the nuclear shipyard and radioactive waste repository in Severodvinsk could cause chronic exposure to low-dose radiation. It is important to expand preventive measures aimed at early detection of vascular damage in nuclear workers and general groups of population residing in the vicinity of hazardous radiation sites.


Author(s):  
Liviu Popa-Simil

It is known for more than 2000 years that Damascus swords’ performances were not possible without the existence and usage of the “Damascus steel”, the first man made nano-hetero structural material that generalized is clearly showing that materials determine ultimate properties of the objects that made of. The actual world energy is manly based carbon emission materials, as coal, heavy oil, methane gas, with negative environment impact. Solar, wind and geothermal energy have also a negative impact on environment and have to be smartly used to minimize it. Nuclear energy, has lower CO2 emission, but because it is in its infancy it is complex, expensive and raises security and proliferation issues, has the potential for large scale accidents, and generates difficulties in dealing with waste fuel dispositioning.The novel developed families of engineered nano-materials, eliminate all the drawbacks of the actual nuclear power, rendering it among the most efficient and environmental friendly energy source. We learned from the global warming that the amount of energy man can produce on Earth is limited at 0.1% of sun delivered on Earth energy of 170 PW, which is of 200 TW, about 100 times more than today if it is chemical pollution free. Thermal pollution remains in place, therefore the upper clean power limit acceptable for the planet is at about 100 TW.The novel nuclear materials were developed in 6 families, each of them bringing in harmony a nuclear agent active inside that material as:- Micro-hetero structures, generally called “cer-Liq-Mesh”, that self-separates the fission products from the nuclear fuel and minimizes their fuel damage, allowing breed&burn to near perfect burning;- Nano-hetero structures generically called “CIci”, that form a super-capacitor, charged by nuclear energy and directly discharged as electricity;- Nano-clustered structure that enhances self-separation of transmutation products;- Fractal immiscible materials with radiation damage self-repairing capabilities eliminating the need for re-cladding in near perfect burning structures- Nano-structures with active NEMS used as fast control of nuclear reactivity by guiding neutrons in desired directions or ultralight shielding for mobile reactors.- Nano-structures that create active-quantum-nuclear-environment for long range nuclear reactions control by using quantum states entanglement and collective quantum states control.The use of these advanced materials in future nuclear energy related application will render a high efficiency, minimal nuclear waste, and optimal nuclear fuel cycle, delivering the needed planetary clean energy at will for the next 10,000 years.


Hydrology ◽  
2021 ◽  
Vol 8 (4) ◽  
pp. 175
Author(s):  
Aline Grard ◽  
Etienne Everbecq ◽  
Pol Magermans ◽  
Jean-François Deliège

Most anthropogenic pollution can be controlled, such as domestic and industrial releases, loads from agriculture, etc. However, some of them, which are associated to illegal discharges, industrial accidents, etc., are more difficult to forecast. This study was performed on the Tereos sugar industry accident that occurred during the night of 9 April 2020, when 88,000 cubic meters of effluents loaded with organic matter discharged in the Scheldt River (a 350 km long transnational river that flows through Northern France and Western Belgium). The accident had dramatic consequences on the receiving watercourse, over 120 km downstream. Fish mortalities have been observed and severe deoxygenation, reaching zero concentration in dissolved oxygen, have impacted river chemical quality. The objective was to understand and describe the dynamics of the chemical pollution and its propagation along the transboundary hydrographic network of the Scheldt. A method based on the processes of organic matter degradation in the river ecosystem was enhanced. It is demonstrated that the accident is doubtless the cause of the water column deoxygenation. This paper shows how the water quality modelling can help to understand and therefore to prevent the consequences of accidental pollution on a river network.


2021 ◽  
Vol 8 ◽  
Author(s):  
Tetsuro Ikuta ◽  
Ryota Nakajima ◽  
Masashi Tsuchiya ◽  
Sanae Chiba ◽  
Katsunori Fujikura

Marine ecosystems are continuously subjected to anthropogenic environmental pollution. Understanding the spread of pollution and the potential risks it poses to deep-sea ecosystems is important for developing better conservation measures. Here, we identified non-negligible levels of persistent organic pollutants in deep-sea chemosynthetic bivalves with limited or no filter feeding. The bivalves were collected from two sites: one located near a highly populated region and the other located relatively far from human activity. Analyses of samples collected nearly every decade in a period of 30 years suggested that environmental policy restrictions might be effective in reducing chemical pollution. However, the detection of contamination in deep-sea chemosynthetic animals suggests that the pollution could be spreading globally to chemosynthetic organisms with limited or no feeding. To protect these highly endemic and vulnerable deep-sea chemosynthetic ecosystems, our findings indicate that further research on chemical contamination and its effects on these ecosystems is required.


Life ◽  
2021 ◽  
Vol 11 (11) ◽  
pp. 1272
Author(s):  
Anton V. Korsakov ◽  
Alexandra A. Golovleva ◽  
Vladislav P. Troshin ◽  
Dmitry G. Lagerev ◽  
Leonid I. Pugach

Background: Radioactive contamination and chemical pollution of the environment can affect the processes of carcinogenesis, including the formation of malignant neoplasms of the ovaries in women. We used the data of official state statistics for 2000–2020 to test the hypothesis about the effect of radioactive contamination (following the Chernobyl disaster) and chemical pollutants on the incidence of ovarian malignancies in the female population of the Bryansk region. Methods: A variety of statistical approaches were used to estimate the incidence of ovarian malignancies, including the Shapiro–Wilk test, Mann–Whitney U test, Spearman’s rank correlation test and linear regression. Results: We did not establish statistically significant differences in the frequency of primary morbidity of women with malignant neoplasms of the ovaries, regardless of the environmental conditions of living. Furthermore, no significant correlations were found between the frequency of primary morbidity of ovarian malignancies, both with the level of contamination by Cesium-137 and Strontium-90, and air pollution with volatile organic compounds, carbon monoxide, sulfur dioxide and nitrogen oxides. A statistically significant increase in the long-term trend in the frequency of ovarian malignant neoplasms was revealed in the areas of chemical pollution (p = 0.02), however, in other territories, no statistically significant regularities were established. The forecast of the frequency of newly diagnosed malignant neoplasms of the ovaries on average in the Bryansk region shows an increase of 12.4% in 2020 in comparison with the real data for 2020, while the largest increase in predicted values is recorded in the territories of radioactive contamination (by 79.6%), and the least in the combined territories (by 6.9%). Conclusions: The results obtained indicate the need for further work to understand the trends in the presence/absence of independent and combined effects of pollutants and the growth of oncogynecological pathology from the perspective of assessing the distant and regional metastasis, histological and immunohistochemical profile of a specific malignant ovarian neoplasm with levels of environmental contamination.


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