Given a labeling c of the edges of a directed graph E by elements of a discrete group G, one can form a skew-product graph E ×c G. We show, using the universal properties of the various constructions involved, that there is a coaction δ of G on C∗(E) such that C∗(E ×c G) is isomorphic to the crossed product C ∗(E) ×δ G. This isomorphism is equivariant for the dual action δ̂ and a natural action ...

The phytochemistry of the genus Piper is rich in terms of numbers of compounds discovered, but given the diversity of this genus and the intraspecific diversity of secondary metabolites in those species that have been examined, Piper chemistry has not been adequately investigated. The natural products chemistry that has been elucidated is well documented and has been the subject of extensive re...

two experiments were conducted to evaluate the crude protein fractionation, in vitro gas production and the biological effects of tannins in alfalfa silage treated with different levels of pistachio by-products (pb) extract. pb was soaked in water with a ratio of 1:5 (w/v) for 12 h. after filtering and concentrating, the crude extract was added to fresh alfalfa to a final concentration of 1%, 2...

this work investigates the use of fenton’s process (ph 5.5 and 6; 0.10-0.50 mm fe(ii); molarratios fe(ii) to h2o2 of 1:5-1:20) combined with flocculation for the treatment of groundwater which is richin natural organic matter (nom) (10.6±0.37 mg c/l) and arsenic (110±6.7 μg/l). changes to the character ofthe residual nom fractions were followed, as well as the removal efficiencies of nom and ar...

In this study, oil was extracted from the liver and visceral fat of Patin (Pangasianodon hypophthalmus) and refined. The yield of oil after refining was 49.98%. The major yield loss (34.20%) happened during the degumming procedure. Fatty acids found in the crude and refined oil were C12:0, C14:0, C14:1, C16:0, C16:1, C18:0, C18:1, C18:2, C18:3, C18:4, C20:0, C20:1, C20:4, C20:5, and C22:6. The ...