A transect across the lower St. Lawrence estuary was occupied to estimate volume transport and nutrient distributions (total dissolved nitrogen and phosphorus, and silicate) during February and May through September. Seaward transport was restricted to the upper 50 m and varied from 17 × 103 m3/s (August) to 129 × 103 m3/s (May). Nutrient and volume transport data are combined to estimate seasonal variability in monthly surface nutrient transport towards the Gulf of St. Lawrence. The estimates vary as follows: 0.72–6.72 × 103 tons N/mo, 0.05–0.48 × 103 tons P/mo and 0.50–6.73 tons Si/mo. Ratios between monthly freshwater input into the estuary and the corresponding values for net seaward transport, which varied from 1.1 to 9.4, are combined with annual data (1960–73) on monthly freshwater input into the estuary to estimate potential annual variability in seaward transport for each of the above months. Observed nutrient data, with the above transport estimates, suggest the possible range in monthly seaward nutrient transport that would be associated with the annual variability in monthly freshwater input into the estuary. Seaward nitrogen transport from May through September, estimated at 2.3 × 104 tons, is considered in relation to published data on the primary production in the western part of the Gulf of St. Lawrence. The estuary supplied a smaller amount of nutrients to the Gulf than has previously been assumed.

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Aromatic nitro compounds can be reduced with sulfurated sodium borohydride to the corresponding amine in high yields ( Z 80%) without affecting ester, nitrile, ether, halide or olefinic groups also present. With ortho-substituted nitro compounds the yields are around 60%.Primary aliphatic nitro compounds are reduced to the corresponding nitrile in high yields. Secondary aliphatic nitro compounds are reduced to mixtures of ketones and the corresponding oxime. Tertiary aliphatic nitro compounds are not reduced.Aromatic nitriles can be reduced to the corresponding amines with an excess of the reducing agent or converted to the corresponding thioamides with an excess of the nitrile.Amides and nitroso can be reduced to the corresponding amines in moderate yields.Les dkrivks nitrds aromatiques peuvent &tre rdduits en amines avec de bons rendements ( Z 80%) par I'hydrure de bore sulfurk, cette rdduction pouvant etre effectude sans affecter les fonctions ester, nitrile, dther, haloghe ou alckne prdsentes. Avec les dkrivks ortho, les rendements sont de I'ordre de 60%.Les dkrivds nitres aliphatiques primaires sont rkduits en nitriles avec de bons rendements. Les derivks nitrks aliphatiques secondaires sont rdduits en un mklange de cktones et d'oximes correspondantes. Les ddrivks nitrks aliphatiques tertiaires ne donnent pas de rkaction.Les nitriles aromatiques peuvent Ctre rdduits en arnines, avec un excks de rdducteur, ou en thioamides, avec un excks de nitrile.Les amides et les nitroso peuvent Ctre rkduits en amines avec des rendements moddrds.

Sulfurated sodium borohydride can reduce oximes to the corresponding amine with yields depending on the steric requirement of the oxime. Intermediate hydroxylamine can be obtained predominantly under appropriate experimental conditions. A reaction mechanism taking into account the availability of only one hydrogen for reduction on the hydride and the production of intermediate hydroxylamine is proposed.