Growth and mortalities of the pink-shrimp Farfantepenaeus brasiliensis Latreille, 1970 and F. paulensis Pérez-Farfante 1967 in Southeast Brazil.

From July, 1999 until July, 2001 data from the pink-shrimp Farfantepenaeus brasiliensis Latreille, 1970 and F. paulensis Pérez-Farfante, 1967 fishery were collected from trawling by the fishing fleet based in Santos/Guarujá-SP. Growth and mortalities of these species were studied. F. brasiliensis and F. paulensis have longevity of 2 years and growth estimates of L Infinity = 29.0 cm and k = 1.24 year-1 for F. brasiliensis and L Infinity = 27.5 cm and k = 1.34 year-1 for F. paulensis. Females reach bigger lengths than males in both species. Natural mortalities (M) were 1.80 and 1.90 year-1 and fishing mortalities (F) were 4.7 and 6.8 year-1 for F. brasiliensis and F. paulensis, respectively. Survival rates are S = 0.15% and 0.02% for F. brasiliensis and F. paulensis, respectively, which are usually low values for shrimps.

Stock assessment and fishery management of the pink shrimp Farfantepenaeus brasiliensis Latreille, 1970 and F. paulensis Pérez-Farfante, 1967 in Southeastern Brazil (23 degrees to 28 degrees S).

Quantitative analyses of the pink shrimp (Farfantepenaeus brasiliensis and Farfantepenaeus paulensis) fisheries were carried out using data collected from July 1999 to July 2001 from the trawling operations of the fishing fleet based in Santos/Guarujá, SP. According to classical models, the fishery is at its maximum sustainable yield. Therefore, reduction of the fishing effort and adequate season and area closures seem to be the best management actions for the pink shrimp fishery.

Spectrophotometric and derivative spectrophotometric determination of aluminium with Hydroxynaphthol Blue.

The reaction of aluminium(III) with Hydroxynaphtol Blue (HNB) in aqueous media at apparent pH 5.5 results in a red complex that is stable for at least 4 hr. Beer's Law is obeyed up to 1.6 microg/ml of aluminium(III) with an apparent molar absorptivity of 1.66 x 10(4) l.mol(-1). cm(-1) at 569 nm. This paper proposes procedures for aluminium(III) determination by ordinary and first-derivative spectrophotometry. The results demonstrated that the linear dynamic range is 0.03-1.60 microg/ml for ordinary spectrophotometry and 11.8-320.0 ng/ml for first derivative spectrophotometry. The HNB is not selectivity for aluminium, but the addition of EDTA allows the aluminium determination in the presence of accepted amounts of Ca(II), Mg(II), Mn(II), Ba(II), Sr(II), Cd(II), Pb(II), La(III), In(III), Bi(III) and Zn(II). The interference of Cu(II) and Hg(II) can be masked by thiosulphate. Ions such as UO(2)(II), Mo(VI), Co(II), Ti(IV) and PO(4)(III) do interfere seriously. This method was applied for aluminium determination in copper-base alloy, zinc-base alloy, magnesium-base alloy, iron ore, manganese ore, cement, dolomite, feldspar and limestone. The results indicated high accuracy and precision.