Applied Science Private University

About: Applied Science Private University is a education organization based out in Amman, Jordan. It is known for research contribution in the topics: Catalysis & Population. The organization has 4124 authors who have published 5299 publications receiving 116167 citations.

The determination of porosity and cellulose content of plant fibers by density methods

Abstract: A combination of the Archimedes method and the technique of helium pycnometry was used to perform accurate measurements of porosity and cellulose content. For this purpose, the densities of hemp, sisal, jute and kapok fibers were measured. An equation was developed using the bulk and absolute density of the fiber and the density of pure cellulose to determine the amount of cellulose a particular fiber contains. As a result, true plant fiber porosity and cellulose content were accurately determined.

Multimolecule ALMA observations toward the Seyfert 1 galaxy NGC 1097

Abstract: Context. The nearby Sy 1 galaxy NGC 1097 represents an ideal laboratory for exploring the molecular chemistry in the surroundings of an active galactic nucleus (AGN). Aims. Exploring the distribution of di erent molecular species allows us to understand the physical processes a ecting the interstellar medium both in the AGN vicinity and in the outer star forming molecular ring. Methods. We carried out 3 mm ALMA observations that include seven di erent molecular species, namely HCN, HCO + , CCH, CS, HNCO, SiO, HC3N, and SO, as well as the 13 C isotopologues of the first two. Spectra were extracted from selected positions and all species were imaged over the central 2 kpc ( 30 00 ) of the galaxy at a resolution of 2.2 00 1:5 00 (150 pc 100 pc). Results. HCO + and CS appear to be slightly enhanced in the star forming ring. CCH shows the largest variations across NGC 1097 and is suggested to be a good tracer of both obscured and early stage star formation. HNCO, SiO, and HC3N are significantly enhanced in the inner circumnuclear disk surrounding the AGN. Conclusions. Di erences in the molecular abundances are observed between the star forming ring and the inner circumnuclear disk. We conclude that the HCN/HCO + and HCN/CS di erences observed between AGN-dominated and starburst (SB) galaxies are not due to a HCN enhancement due to X-rays, but rather this enhancement is produced by shocked material at distances of 200 pc from the AGN. Additionally, we claim that lower HCN/CS is a combination of a small underabundance of CS in AGNs, together with excitation e ects, where a high density gas component ( 10 6 cm 3 ) may be more prominent in SB galaxies. However, the most promising are the di erences found among the dense gas tracers that, at our modest spatial resolution, seem to outline the physical structure of the molecular disk around the AGN. In this picture, HNCO probes the well-shielded gas in the disk, surrounding the dense material moderately exposed to the X-ray radiation traced by HC3N. Finally SiO might be the innermost molecule in the disk structure.