It is little more than jifty years since the Jirst manufacture of nitric acid by the oxidation of ammonia over a platinum catalyst. Ostwald’s original industrial plant had an output of some 100 tons of acid a year; today the world capacity for nitric acid manufacture by this process is about ten million tons a year. This article traces the beginnings and early developments of the process until ...

Cadmium ions influence on the content of anthocyanins as non-plastid pigments and the activity of phenylalanine ammonia-lyase (EC 4.3.1.24) as primary enzyme of their biosynthesis in two lettuce varieties (Lactuca sativa L.) with different anthocyanin content was investigated. The increases in anthocyanin content and enzymatic activity of phenylalanine ammonia-lyase of both lettuce plant variet...

The current critical level for ammonia (CLE(NH3)) in Europe is set at 8mug NH(3) m(-3) as an annual average concentration. Recent evidence has shown specific effects of ammonia (NH(3)) on plant community composition (a true ecological effect) at much smaller concentrations. The methods used in setting a CLE(NH3) are reviewed, and the available evidence collated, in proposing a new CLE(NH3) for ...

In the manufacturing of ammonium nitrate, a condensate containing ammonia and ammonium nitrate is obtained. The concentrations of these species are in practically all cases too high for direct discharge into a water recipient. At some plants, some of the dilute ammonium nitrate solution can be spread out on adjacent farmland, as it is a fertilizer, but commonly, nitric acid is added to this str...

Phenylalanine ammonia-lyase (PAL) performs a major role in the biosynthesis of polyphenolic compounds, which are involved in the defense mechanism in harsh environments related to different stimuli. The present study was carried out to detect the activity of phenylalanine ammonia-lyase in different plant parts of Anacardium occidentale such as flower, young leaves, shoot tip, mature leaves, raw...

Struvite precipitation proved to be an effective method of ammonia removal from the landfill leachate from two separate sources. Batch tests for precipitating struvite yielded several different chemical combinations that were effective at removing ammonia from leachate. The struvite precipitate samples were quite heterogeneous in composition, containing a mixture of short and thick crystals, el...

Design of an ammonia reactor was conceived as part a series item designs for plant in Cyprus. The Chemical and Mechanical aspects the design were considered. Optimization these studied, worked on, & discussed. safety, environmental legal regulations relevant followed concerned.

The Biocos strategy as a cyclical time controlled activated sludge system shows a great variability in operation and control. One topic such a type of treatment plant has to deal with is the optimum relation between aerobic and anoxic conditions. The aeration control has to adapt the length of the nitrification phases to the current constraints in order to save operational costs and maximise ni...

Efficient livestock production from pasture requires an understanding of preference and selection by grazing animals. Selective grazing influences diet not just in the short-term but more importantly, in the long-term through its affect on pasture composition. This paper summarises techniques developed to explore the nutritional basis for preference in complementary indoor and field studies. In...