Creating nanoporous graphene with swift heavy ions

This article has an erratum: DOI 10.1016/j.carbon.2017.03.065We examine swift heavy ion-induced defect production in suspended single layer graphene using Raman spectroscopy and a two temperature molecular dynamics model that couples the ionic and electronic subsystems. We show that an increase in the electronic stopping power of the ion results in an increase in the size of the pore-type defects, with a defect formation threshold at 1.22–1.48 keV/layer. We also report calculations of the specific electronic heat capacity of graphene with different chemical potentials and discuss the electronic thermal conductivity of graphene at high electronic temperatures, suggesting a value in the range of 1 Wm−1 K−1. These results indicate that swift heavy ions can create nanopores in graphene, and that their size can be tuned between 1 and 4 nm diameter by choosing a suitable stopping power.Peer reviewe

Kinetics of thermo heterogeneous process under non-isothermal terms on the titanium carbide : a study on the different irradation conditions

Please read abstract in the article.http://jomardpublishing.com/journals.aspx?lang=en&id=13am2023Physic

Global burden of disease due to rifampicin-resistant tuberculosis in 2020: a mathematical modelling analysis

In 2020, almost half a million individuals developed rifampicin-resistant tuberculosis (RR-TB). We estimated the global burden of RR-TB over the lifetime of affected individuals. We synthesized data on incidence, case detection, and treatment outcomes in 192 countries (99.99% of global tuberculosis). Using a mathematical model, we projected disability-adjusted life years (DALYs) over the lifetime for individuals developing tuberculosis in 2020 stratified by country, age, sex, HIV, and rifampicin resistance. Here we show that incident RR-TB in 2020 was responsible for an estimated 6.9 (95% uncertainty interval: 5.5, 8.5) million DALYs, 44% (31, 54) of which accrued among TB survivors. We estimated an average of 17 (14, 21) DALYs per person developing RR-TB, 34% (12, 56) greater than for rifampicin-susceptible tuberculosis. RR-TB burden per 100,000 was highest in former Soviet Union countries and southern African countries. While RR-TB causes substantial short-term morbidity and mortality, nearly half of the overall disease burden of RR-TB accrues among tuberculosis survivors. The substantial long-term health impacts among those surviving RR-TB disease suggest the need for improved post-treatment care and further justify increased health expenditures to prevent RR-TB transmission

Development of methods for the preparation of radiopure ⁸²Se sources for the SuperNEMO neutrinoless double-beta decay experiment

A radiochemical method for producing 82Se sources with an ultra-low level of contamination of natural radionuclides (40K, decay products of 232Th and 238U) has been developed based on cation-exchange chromatographic purification with reverse removal of impurities. It includes chromatographic separation (purification), reduction, conditioning (which includes decantation, centrifugation, washing, grinding, and drying), and 82Se foil production. The conditioning stage, during which highly dispersed elemental selenium is obtained by the reduction of purified selenious acid (H2SeO3) with sulfur dioxide (SO2) represents the crucial step in the preparation of radiopure 82Se samples. The natural selenium (600 g) was first produced in this procedure in order to refine the method. The technique developed was then used to produce 2.5 kg of radiopure enriched selenium (82Se). The produced 82Se samples were wrapped in polyethylene (12 μm thick) and radionuclides present in the sample were analyzed with the BiPo-3 detector. The radiopurity of the plastic materials (chromatographic column material and polypropylene chemical vessels), which were used at all stages, was determined by instrumental neutron activation analysis. The radiopurity of the 82Se foils was checked by measurements with the BiPo-3 spectrometer, which confirmed the high purity of the final product. The measured contamination level for 208Tl was 8-54 μBq/kg, and for 214Bi the detection limit of 600 μBq/kg has been reached.</p

The Application Uti Possidetis Principle in Africa

Uti possidetis originating from Roman jus civile which later transformed into a principle of interstate relations dealing with a transformation of former administrative borders into international boundaries of the newly independent states in Latin America was also effectively applied upon decolonisation in Africa in XX century. This article considers the relevant state practice of the African states and the OAU’s position on application of uti possidetis principle. The article also analyses the Burkina Faso vs Mali case which is one of the substantial cases on application of uti possidetis pinciple

Employment Of Population And Its Geographical Study

The indicators, types and forms of employment, indicators reflecting the effectiveness of the employment, and the factors affecting population employment were mentioned in this work. In addition, the description is also given to the characteristics of the formation of the labor market. Along with this, in this chapter, the main directions of state policy based on the provision of population with employment in some countries have been

Structure and thermal analysis of Ba<inf>0.5</inf> La<inf>0.5</inf> MnO<inf>3</inf> polycrystalline powder

© 2019 World Scientific Publishing Company. The structure and thermal properties of Ba0.5La0.5MnO3 polycrystalline powder have been investigated using X-ray diffraction (XRD), Scanning Electron Microscopy (SEM), X-ray photoelectron spectroscopy (XPS), thermogravimetric analysis (TGA) and differential scanning calorimetry (DSC) techniques. The structural studies have shown that Ba0.5La0.5MnO3 compound crystallizes in perovskite structure with Pm-3m cubic symmetry group. The lattice parameters were obtained to be a = b = c = 3.9073 Å. Mass changes have been observed from thermogravimetric (TG) and differential thermogravimetric (DTG) curves obtained in a wide temperature interval of 30-950°C. Free energy and enthalpy changes for all observed transformations were determined. Observed endo and exo effects