Nitrite and ammonia are two of the most common toxic nitrogenous pollutants in aquatic ecosystem, which can pose a serious threat to health organisms. Cladocerans, as an important part freshwater will inevitably be harmed by these pollutants. To evaluate combined effects on cladocerans, we simulated 15 combinations five nitrite concentrations (0, 0.5, 2, 4, 8 mg L −1 ) three 0.1, 1 study change...

The Cover Feature represents the concept of employing two (frustrated) Lewis acid-base pairs within a pincer-type compound to activate defiant N2-molecule; N≡N triple bond is thereby extended by remarkable 0.34 Å. Once caught tailor-made activator molecule, N2 prone stepwise reduction with hydride (compensated protons) finally release one molecule ammonia, whereas remaining nitrogen could not b...

The need for gas compound measurement concerns overall three domains: environmental monitoring, emission measurement and risk assessment. These fields are different because of concentration range (from 10–3 to thousands mg.m–3). A fast technique has been developed based on UV spectrophotometry. Simple robust optics and absence of interference from water vapour and carbon dioxide are two of the ...

In the preceding paper (1) an enzyme preparation was described which catalyzed the synthesis of citrulline from ornithine in the presence of adenosinetriphosphate (ATP), ammonia, magnesium and bicarbonate ions, and carbamylglutamate. Glutamic acid could not replace the latter compound. Balance studies have failed to provide satisfactory evidence for the r61e of carbamylglutamate in this system....

In a previous paper [J. Subotnik, Y. Shao and W. Liang, and M. Head-Gordon, J. Chem. Phys., 2004, 121, 9220], we proposed a new and efficient method for computing localized Edmiston-Ruedenberg (ER) orbitals, which are those localized orbitals that maximize self-interaction. In this paper, we improve upon our previous algorithm in two ways. First, we incorporate the resolution of the identity (R...

Ergothioneine (ESH) is a low-molecular-mass thiol present in millimolar concentrations in a limited number of tissues, including erythrocytes, kidney, seminal fluid and liver; however, its biological function is still unclear. In the present study we investigated the role of ESH in the catabolism of S-nitrosoglutathione (GSNO). The results show that: (1) GSNO decomposition is strongly influence...

In biological nitrogen fixation the key intermediate compound, defined as the end product of the fixation reaction and the initial reactant of assimilation, is believed to be either ammonia or hydroxylamine. Burris and Wilson (1945) noted that these two possibilities need not be mutually exclusive but may occur simultaneously, depending on the concentrations of the carbon compounds serving as a...

Intensive livestock production is connected with a number of environmental effects, including emissions of ammonia (NH3), greenhouse gases (CH4 and N2O), odour, and particulate matter (PM10 and PM2.5). Possible strategies for emission reduction include feed management, adaptation of housing design, and, in case of mechanically ventilated animal houses, the application of end-of-pipe air treatme...

Dietary protein intake is the most important factor determining milk production, milk composition, milk nitrogen efficiency, urinary nitrogen losses, urea content in milk and consequently, ammonia emissions from dairy cow manure. According to the nutrition requirements two main protein sources are available for cows: rumen degradable protein, provided to the animal through ruminally synthesized...

The electroreduction of benzophenone in liquid ammonia was studied by cyclic voltammetry. In anhydrous solutions, the reduction occurs in two reversible one-electron steps producing the anion radical and the dianion. In the presence of alcohol, the first reduction is unaffected and the second reduction wave becomes irreversible and is shifted toward positive potentials, following qualitatively ...