according to environmental protection organization of iran, maximum permissible concentration of residual phosphorus in treated municipal wastewater is 1 mg /l-p. the total average phosphorus concentration in raw municipal wastewater is about 8 mg / l; about 70 percent of the incoming phosphorus normally is discharged with secondary treatment plant effluents. in this research, the role of addin...

In order to elucidate the reaction mechanism of the cyclization between an ethynyl group and an imino group at the ortho-position on an aromatic ring to afford isoquinolines, reaction of 2-ethynylbenzaldehydes under various conditions was examined. It is concluded that reaction proceeds via an ionic process and the isoquinoline 4-hydrogen atom derives from the solvent. In addition, it was found...

The reaction between COS and aqueous solutions of primary andsecondary amines has been studied by means of the stirred cell technique. Kinetic experiments at temperatures 283 to 333 K were carried out with MEA, DGA, DEA, DIPA, MMEA, AMP, and MOR. All kinetic experiments could be described by a zwitterion reaction mechanism similar to the mechanism proposed by Caplow (1968) for the reaction betw...

Nature's repertoire of biosynthetic transformations has recently been recognized to include the Diels-Alder cycloaddition reaction. Evidence now exists that there are enzymes that mediate the Diels-Alder reaction in secondary metabolic biosynthetic pathways. 2002 marked the 100th anniversary of Alder's birth and 75 years since the discovery of the Diels-Alder reaction. It would appear that livi...

We propose here a verifiable mechanism for the bacterial bioluminescence reaction involving a dioxirane intermediate. Participation of the dioxirane predicts either formation of an excited carbonyl, rather than the flavin, as the primary excited state in the reaction, or, through a CIEEL mechanism, the C4a hydroxyflavin or the chromophore of a secondary emitter protein could become excited. We ...

In vivo studies of murein biosynthesis show that newly synthesized murein unexpectedly differs in its chemical composition from preexisting murein. New murein is loosely crosslinked with the preexisting sacculus; in a maturation process involving further transpeptidation, the final stage of crosslinkage in murein is achieved. Newly inserted murein initially carries pentapeptide subunits, which ...

We report a new class of catalytic reaction: the thermal substitution of a secondary and or tertiary alkyl halide with a nitrogen nucleophile. The alkylation of a nitrogen nucleophile with an alkyl halide is a classical method for the construction of C-N bonds, but traditional substitution reactions are challenging to achieve with a secondary and or tertiary alkyl electrophile due to competing ...

A simple protocol for iron-catalyzed cross-coupling of nonactivated secondary alkyl bromides and iodides with alkynyl Grignard reagents at room temperature has been developed. A wide range of secondary alkyl halides and terminal alkynes are tolerated to afford the substituted alkynes in good yields. A slight modification of the reaction protocol also allows for cross-coupling with a variety of ...

Introduction Hemophagocytic Lymphohistiocytosis (HLH) is a rare histiocyte disorder associated with perforin-dependent cytotoxic function, characterized by a highly stimulated, but ineffective, immune response to antigens, which results in life-threatening cytokine storm and inflammatory reaction. Both familial and secondary forms have been described. Secondary HLH in associated with infections...

Capacitation (modifications required for gamete fusion) is produced by incubating guinea-pig spermatozoa in vitro in a chemically defined medium. It is shown that during such incubation a net uptake of Ca2+ by the sperm occurs in two distinguishable phases. An initial loose association of Ca2+, possibly to surface sites, is unaffected by agents (Mg2+, inhibitors of mitochondiral function) that ...