Daegu University

About: Daegu University is a education organization based out in Daegu, South Korea. It is known for research contribution in the topics: Population & Apoptosis. The organization has 1721 authors who have published 3844 publications receiving 62059 citations.

Biochar properties and eco-friendly applications for climate change mitigation, waste management, and wastewater treatment: A review

Abstract: Pyrolysis is one of the most promising technologies for the conversion of biomass into high-value products such as bio-oil, syngas, and biochar in the absence of oxygen High yield biochar can be produced through torrefaction or slow pyrolysis The efficiency of biochar production from biomass is highly dependent on the pyrolysis temperature, heating rate, type and composition of feedstock, particle size, and reactor conditions Application of biochar to agriculture may have a significant effect on reducing global warming through the reduction of greenhouse gas (GHG) emissions and the sequestering of atmospheric carbon into soil At the same time, biochar can help improve soil health and fertility, and enhance agricultural production Livestock manure, along with waste-feed residues and bedding materials, is a potential source of biochar This waste emits significant amounts of GHGs adding to global warming and threatening the environment in other ways The environmental challenges caused by agricultural and animal-waste disposal can be reduced by recycling the waste using pyrolysis, into biochar, energy, and value-added products Biochar can act as a sorbent for organic and inorganic contaminants and can efficiently remove these materials from affected waters Contaminant removal is mainly based on the presence of functional groups and charges on the surface of the biochar Thus, biochar can help to improve food security by contributing to sustainable production systems and maintaining an eco-friendly environment This review details the principles and concepts involved in biochar production, the factors that affect biochar quality, as well as the applications of biochar

Constraining the Symmetry Parameters of the Nuclear Interaction

Abstract: One of the major uncertainties in the dense matter equation of state has been the nuclear symmetry energy. The density dependence of the symmetry energy is important in nuclear astrophysics, as it controls the neutronization of matter in core-collapse supernovae, the radii of neutron stars and the thicknesses of their crusts, the rate of cooling of neutron stars, and the properties of nuclei involved in r-process nucleosynthesis. We show that fits of nuclear masses to experimental masses, combined with other experimental information from neutron skins, heavy ion collisions, giant dipole resonances and dipole polarizabilities, lead to stringent constraints on parameters that describe the symmetry energy near the nuclear saturation density. These constraints are remarkably consistent with inferences from theoretical calculations of pure neutron matter, and, furthermore, with astrophysical observations of neutron stars. The concordance of experimental, theoretical and observational analyses suggests that the symmetry parameters S v and L are in the range 29.0‐32.7 MeV and 40.5‐61.9 MeV, respectively, and that the neutron star radius, for a 1.4 M star, is in the narrow window 10.7 km < R < 13.1 km (90% confidence). We can also set tight limits to the size of neutron star crusts and the fractional moment of inertia they contain, as well as the overall moment of inertia and quadrupole polarizability of 1.4 M stars. Our results also have implications for the disk mass and ejected mass of compact mergers involving neutron stars.