Horizons: Nuclear Astrophysics in the 2020s and Beyond

Nuclear Astrophysics is a field at the intersection of nuclear physics and astrophysics, which seeks to understand the nuclear engines of astronomical objects and the origin of the chemical elements. This white paper summarizes progress and status of the field, the new open questions that have emerged, and the tremendous scientific opportunities that have opened up with major advances in capabilities across an ever growing number of disciplines and subfields that need to be integrated. We take a holistic view of the field discussing the unique challenges and opportunities in nuclear astrophysics in regards to science, diversity, education, and the interdisciplinarity and breadth of the field. Clearly nuclear astrophysics is a dynamic field with a bright future that is entering a new era of discovery opportunities.Comment: 96 pages. Submitted to Journal of Physics

Horizons: nuclear astrophysics in the 2020s and beyond

Nuclear astrophysics is a field at the intersection of nuclear physics and astrophysics, which seeks to understand the nuclear engines of astronomical objects and the origin of the chemical elements. This white paper summarizes progress and status of the field, the new open questions that have emerged, and the tremendous scientific opportunities that have opened up with major advances in capabilities across an ever growing number of disciplines and subfields that need to be integrated. We take a holistic view of the field discussing the unique challenges and opportunities in nuclear astrophysics in regards to science, diversity, education, and the interdisciplinarity and breadth of the field. Clearly nuclear astrophysics is a dynamic field with a bright future that is entering a new era of discovery opportunities

Inuloxins A???D, phytotoxic bi-and tri-cyclic sesquiterpene lactones produced by Inula viscosa: Potential for broomrapes and field dodder management

Four phytotoxic bi- and tri-cyclic sesquiterpene lactones, named inuloxins A???D, were isolated together with the known a-costic acid, from the aerial parts of Inula viscosa (family Asteraceae), a widespread Mediterranean plant well known for its content of pharmacologically active metabolites. The structures of inuloxins A???D were established by spectroscopic and chemical methods and determined to be: (4E,7R*,8R*,10S*)-3-oxo-germacra-4,11(13)-dien-8b-12-olide (A), its 11,13-dihydro analogue (B), (5*, 7R*,8R*,10R*)-1,15-methylene-5b-hydroxy-eudesm-1(15),11(13)-dien-8b-12-olide (C), and (7R*,8R*)-1,4-dimethyl-4-hydroxy-secoeudesm-5(10),11(13)-dien-8b-12-olide (D). The S absolute stereochemistry at C-5 of 5-hydroxyhexan-2-yl side chain of inuloxin D was assigned by applying an advanced Mosher???s method. The phytotoxic activity of inuloxins A???D, that of the diazo and monoacetyl derivatives (of inuloxin A and C, respectively), as well as that of a-costic acid was evaluated against two parasitic plant species, i.e. crenate broomrape (Orobanche crenata) and field dodder (Cuscuta campestris). Inuloxins A, C and D were the most active on both parasites and caused up to 100% inhibition of the seed germination. Inuloxin B was less active on Cuscuta and completely inactive against Orobanche. The main metabolite a-costic acid had a suppressive effect on the dodder seed germination but had a stimulating action on the broomrape seed germination. These preliminary results allowed to suppose some structure???activity relationships

Equilibrium and kinetic studies of methyl orange and Rhodamine B adsorption onto prepared activated carbon based on synthetic and agricultural wastes

The present study is focused on the valorization of a synthetic (tires) and agricultural (date pit) waste using a simple method in order to obtain an interesting activated carbon, which has been compared with commercial coal. Prepared active carbon is characterized by various techniques such as elemental analysis Brunauer, Emmett and Teller, elementary analysis, scanning electron microscopy (SEM), X-ray photoelectron spectroscopy (XPS), and temperature programmed desorption (TPD). Results of characterization of the two prepared carbons with chemical activation show clearly that a temperature of 550°C and particle diameter of 800 μm give interesting proprieties. The specific surface area reached 770 and 1,030 m2g, respectively, for the different active carbons obtained from tires and date pits. The ratio of carbon in the two prepared activated carbons reached 83% and 93%, respectively for the elementary analysis and surface chemical composition, and the analysis by TPD shows the formation of different functional groups (as radicals, carbonyl groups, and aromatic ethylinique). In order to evaluate the efficiency of these adsorbents, we selected an anionic dye (orange methyl) as a pollutant. Kinetic results show that the adsorption equilibrium is reached at around 60 min with an adsorbed amount of 21.42 and 38.83 mg/g for the tire activated carbon (TAC) and the date pits activated carbon (DPAC) , respectively. The different isotherms were well fitting by the Freundlich model

Preparation of activated carbon based on synthetic and agricultural wastes: application to the adsorption of methyl orange

This study focus on the optimization of operating conditions for activated carbons preparation starting from synthetic waste (tires) and agricultural waste (date pits) by chemical activation. The experimental design was used in order to determinate the optimal conditions for the preparation of a precursor with high properties. The results show that a temperature of 550°C and particle diameter of 800 μm are interesting. The specific surface area reached 770 and 1030m2/g respectively for the active carbons obtained from tires and date pits. In order to evaluate the efficiency of these adsorbents, we selected an anionic dye (orange methyl) as a pollutant. Kinetic results show that the adsorption equilibrium is reached at around 60 min with an adsorbed amount of 21.42 mg/ g and 38.83 mg/g for the TAC (Tire Activated Carbon) and the DPAC (Date Pits Activated Carbon) respectively. The different isotherms were well fitting by Freundlich model