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DNA origami nanostructures are emerging as a bottom-up nanopatterning approach. Direct combination of this approach with top-down nanotechnology, such as ion beams, has not been considered because of the soft nature of the DNA material. Here we demonstrate that the shape of 2D DNA origami nanostructures deposited on Si substrates is well preserved upon irradiation by ion beams, modeling ion implantation, lithography, and sputtering conditions. Structural changes in 2D DNA origami nanostructures deposited on Si are analyzed using AFM imaging. The observed effects on DNA origami include structure height decrease or increase upon fast heavy ion irradiation in vacuum and in air, respectively. Slow- and medium-energy heavy ion irradiation results in the cutting of the nanostructures or crater formation with ion-induced damage in the 10 nm range around the primary ion track. In all these cases, the designed shape of the 2D origami nanostructure remains unperturbed. Present stability and nature of damages on DNA origami nanostructures enable fusion of DNA origami advantages such as shape and positioning control into novel ion beam nanofabrication approaches.

We performed experiments of implantation of energetic sulfur ions (105 keV) into 2:1 water:propane ices at 80 K and analyzed the resulting refractory organic matter with ultrahigh-resolution mass spectrometry. Our goal was to characterize the organic matter processed in the surface conditions of Europa, where it would receive a heavy flux of energetic particles, including sulfur ions, and determine whether organosulfurs could be formed in these conditions, using the simplest alkane that can exist in solid form on Europa’s surface. We find that the produced organic matter contains a large variety of both aliphatic and aromatic compounds (several thousand unique formulae), including polycyclic aromatic hydrocarbons (PAHs), with masses up to 900 amu. A large number of aromatic hydrocarbons is found along with oxygenated, mostly aliphatic, compounds. Organosulfurs are found in both CHS and CHOS form, demonstrating they can be formed from any organic compound through sulfur implantation. These organosulfurs’ properties (aromaticity, mass) appear similar to the rest of the organic matter, albeit their low quantity does not allow for a thorough comparison. Our results have implications for the type of refractory organic matter that could be observed by the JUICE and Europa Clipper space missions and how the surface of Europa could generate complex organics, including PAHs and organosulfurs, that could then enrich the subsurface ocean. In particular, they indicate that a large diversity of organic matter, including organosulfurs, can be formed from simple precursors in a geologically short time frame under the ion flux that reaches Europa.

In this paper, we compare the development and possibilities for improvement of waste management in three countries: Slovakia, the Czech Republic, and Poland. Waste management is part of the circular economy. The circular economy is the basis for waste management today. This applies to municipal waste management, too. In this paper, we work with data available in the Eurostat database. We mainly deal with municipal waste in the three chosen countries. The output of this paper is an assessment of indicators such as recycling rates and waste production. The outputs are documented graphically.

The valence ionization of uracil and mixed water–uracil clusters has been studied experimentally and by ab initio calculations. In both measurements, the spectrum onset shows a red shift with respect to the uracil molecule, with the mixed cluster characterized by peculiar features unexplained by the sum of independent contributions of the water or uracil aggregation. To interpret and assign all the contributions, we performed a series of multi-level calculations, starting from an exploration of several cluster structures using automated conformer-search algorithms based on a tight-binding approach. Ionization energies have been assessed on smaller clusters via a comparison between accurate wavefunction-based approaches and cost-effective DFT-based simulations, the latter of which were applied to clusters up to 12 uracil and 36 water molecules. The results confirm that (i) the bottom-up approach based on a multilevel method [Mattioli et al. Phys. Chem. Chem. Phys. 23, 1859 (2021)] to the structure of neutral clusters of unknown experimental composition converges to precise structure–property relationships and (ii) the coexistence of pure and mixed clusters in the water–uracil samples. A natural bond orbital (NBO) analysis performed on a subset of clusters highlighted the special role of H-bonds in the formation of the aggregates. The NBO analysis yields second-order perturbative energy between the H-bond donor and acceptor orbitals correlated with the calculated ionization energies. This sheds light on the role of the oxygen lone-pairs of the uracil CO group in the formation of strong H-bonds, with a stronger directionality in mixed clusters, giving a quantitative explanation for the formation of core–shell structures. [ABSTRACT FROM AUTHOR]

We have performed classical molecular dynamics simulations of 3 keV Ar + (C24H12)n(C60)m collisions where (n,m) = (3,2),(1,4),(9,4) and (2,11). The simulated mass spectra of covalently bound reaction products reproduce the main features of the corresponding experimental results reported by Domaracka et al., Phys. Chem. Chem. Phys., 2018, 20, 15052-15060. The present results support their conclusion that molecular growth is mainly driven by knockout where individual atoms are promptly removed in Rutherford type scattering processes. The so formed highly reactive fragments may then bind with neighboring molecules in the clusters producing a rich variety of growth products extending up to sizes containing several hundreds of atoms, and here we show examples of such structures. In addition, knocked out atoms may be absorbed such that e.g. hydrogenated coronene and fullerene molecules are formed. [ABSTRACT FROM AUTHOR]

Aims. Astrophysical ices on dust grain mantles in the interstellar medium (ISM) and dense circumstellar envelopes (CSEs) are continuously exposed to galactic cosmic rays (GCRs). In a laboratory setting, we studied the physical and chemical modifications of ice layers induced by energetic heavy ions as GCR analogues. The ice layers used have a molecular composition similar to that of icy grain mantles. Methods. Mixtures of H2O:CO:CH3OH molecules (percentages 73:24:3, 68:30:3, and 58:38:3) were condensed on a substrate at 15 K and irradiated with 40 MeV 58Ni11+ ion beams. Irradiation-induced modifications were followed using the mid-infrared absorption spectroscopy technique. Results. We observed the evolution of infrared bands of CO2, HCO, HCOOH, CH4, H2CO,H2O2, and more complex synthesised molecules. From the molecular column densities, cross-sections and sputtering yields were determined and compared to published results of water and carbon monoxide. Analysis of the chemical modifications reveals that the precursors are easily destroyed when they are in a molecular mixture, while others are desorbed. Conclusions. The main radiolitic modifications induced by GCR irradiations are molecular decomposition and sputtering. Extrapolation to astrophysical radiation conditions shows a strong dependence on the intensity of the GCR distributions at low energies, which allows the analysis of the ice evolution at timescales comparable to those of the ISM and CSE. [ABSTRACT FROM AUTHOR]

The emergence of the new SARS-CoV-2 virus two years ago strongly affected economic life and labour markets around the world. The pandemic affected many sectors, including the mining industry. Coal companies have had to cope with the challenges and adapt their operations to the situation. Due to the peculiarities of the mines, not only to the hazardous factors and conditions prevailing underground but also to the large number of employees who usually move in groups in the plants, the emergence of a new threat caused by a biological agent posed a real challenge for them. The aim of this paper was to present the initiatives and measures taken in the coal mining sector to ensure the safety of workers during a pandemic. The guidelines for the operation of mining plants during the SARS-CoV-2 epidemic were analysed, as well as the identification of locations in mining plants particularly vulnerable to infection with the virus. We also presented how the pandemic period affected the operations of a selected coal company in Poland from an economic point of view.

In this paper, we compare the development and possibilities for improvement of waste management in three countries: Slovakia, the Czech Republic, and Poland. Waste management is part of the circular economy. The circular economy is the basis for waste management today. This applies to municipal waste management, too. In this paper, we work with data available in the Eurostat database. We mainly deal with municipal waste in the three chosen countries. The output of this paper is an assessment of indicators such as recycling rates and waste production. The outputs are documented graphically. [ABSTRACT FROM AUTHOR]

This article investigates the radiolysis of a mixture of nitric acid with water (HNO3:H2O) at 16 K in high-vacuum (residual pressure < 10−6 mbar). A nitric acid-water ice film was exposed to 40 MeV 58Ni11+ ion beam in a heavy ion accelerator facility in France. For this astrochemically- and atmospherically-relevant ice mixture of nitric acid and water, we analyze the possible formation and destruction processes of N–O bearing species, thus providing spectroscopic data in the infrared (IR) region for theoretical, laboratory and observational future studies. The irradiation synthetized 18 species which were posteriorly examined by infrared spectroscopy: N2O, NH3, NO, NO2 and H x N y O z molecules, such as hidroxylamine (NH2OH), nitrous acid (HONO) as well as other species with bonding N–O, N–H and H–O–N converting surface-adsorbed nitrogen oxides into astrochemically active NO x. The interaction of HNO3 and H2O originates H–N–O molecular complexes, which were investigated as particular cases of the hydrogen-bonded species formed by a more electronegative atom (N or O) interacts intra or intermolecularly with a donor atom (N or O) and observed in the interstellar medium with higher quantities or great abundances. The HNO3 and H2O destruction cross sections have been determined to be 8.5 × 10−13 and 1.2 × 10−13 cm2, respectively, for the mentioned experimental conditions. [ABSTRACT FROM AUTHOR]

The interstellar chemistry of nitrogen is considerably less understood than the chemistry of other common elements, such as carbon and oxygen. Even though a relatively large number of species containing nitrogen atoms have already been detected in the interstellar medium, only six of them bear a nitrogen–oxygen (N–O) bond. Some astrophysical and primeval Earth models suggest that N–O species, such as hydroxylamine (NH2OH), are potential precursors of prebiotic amino acids, and even peptides. In this work, we have analyzed an apolar ice mixture of N2:CO of astrophysical interest to investigate possible formation mechanisms of N–O bearing molecules due to processing of the sample by 64Ni24+ 538 MeV ions (8.4 MeV/u) at 14 K. The results show the formation of simple nitrogen oxides (⁠|$\rm {N_{1 - 2}}{O_y})$|⁠ , but no CN–O species of any kind. We have also determined the formation cross-sections of some of the products, as well as the destruction cross-sections of precursors and products. The results presented here are discussed in light of our previous work on the processing of a NH3:CO ice mixture, which have found no N–O bearing molecules at all. [ABSTRACT FROM AUTHOR]

H2O and CO molecules are the main constituents of the interstellar dust grain ice mantles. Infrared spectra of the ices in line of sights of young stellar objects and background stars have shown that the CO stretching vibration band can be decomposed into three main components: 2143, 2139, and 2136 cm−1, assigned to CO in different environment sites. The relative strengths between the components have been associated with an evolutionary track of the interstellar molecular clouds. H2O:CO (3:2) and (10:1) ice samples were irradiated by 0.79 MeV/u 58Ni13+ ions to simulate the effects produced by heavy ion cosmic rays in typical interstellar ice mixtures. The CO stretching vibration band is decomposed into six Gaussian functions (2150, 2144, 2141, 2138, 2136, and 2133 cm−1) and their integrated absorbances were measured as a function of fluence. The results show that, at the final fluence, the component 2138 cm−1 is the main component of the CO stretching vibration band. The component 2150 cm−1 disappears at the beginning of irradiation. Based on the present and previous results, a time-scale for the components in the interstellar ices is proposed. For H2O:CO ices in the interstellar medium, it is predicted that, after 1 Ma, the main components of the CO stretching vibration band are the 2138 and 2141 cm−1, due to the CO monomers and dimers, respectively. [ABSTRACT FROM AUTHOR]

DNA origami nanostructures are emerging as a bottom-up nanopatterning approach. Direct combination of this approach with top-down nanotechnology, such as ion beams, has not been considered because of the soft nature of the DNA material. Here we demonstrate that the shape of 2D DNA origami nanostructures deposited on Si substrates is well preserved upon irradiation by ion beams, modeling ion implantation, lithography, and sputtering conditions. Structural changes in 2D DNA origami nanostructures deposited on Si are analyzed using AFM imaging. The observed effects on DNA origami include structure height decrease or increase upon fast heavy ion irradiation in vacuum and in air, respectively. Slow- and medium-energy heavy ion irradiation results in the cutting of the nanostructures or crater formation with ion-induced damage in the 10 nm range around the primary ion track. In all these cases, the designed shape of the 2D origami nanostructure remains unperturbed. Present stability and nature of damages on DNA origami nanostructures enable fusion of DNA origami advantages such as shape and positioning control into novel ion beam nanofabrication approaches., (Copyright © 2024, Sala et al.)