Satoru Kanamori

Kosa aerosol as eolian carrier of anthropogenic material

Abstract Nine samples of three Kosa aerosols (Asian dust) were collected at Yaku Island located ∼900 km southeast off the coast of China, during winter and spring 1988. Aluminum, Mg, Ca and Fe were present in highest concentration, but, as reported previously, high levels of NO 3 and SO 4 2 were also found. The increase in NO 3 and SO 4 2 levels in Kosa aerosol compared with normal aerosol during non-Kosa events were associated with the coarse size fraction, whereas no increase was found in the fine size fraction. The high correlation coefficient between NO 3 , non-sea-salt SO 4 2 , and total surface area of aerosol particles for all size fractions of the coarse fraction indicate that these ions are deposited on and transported with the Kosa aerosol.

Calcium-alkalinity relationship in the North Pacific

The dissolution of calcium carbonate in deep ocean water causes variation in calcium concentration (ΔCa) and alkalinity (ΔTA) in the ratio of one to two. The decomposition of organic matter generates nitric acid, phosphoric acid and sulfuric acid. A proton flux which is derived from this process also changes alkalinity. Using the variation in nitrate concentration (ΔNO3) as an index of the proton flux, the relationship betweenΔCa,ΔTA andΔNO3 is expressed asΔCa=0.5ΔTA+0.63ΔNO3 The values of ΔCa obtained from direct measurements in the North Pacific are in good agreement with the values estimated from this equation.

Computer-processed potentiometric titration for the determination of calcium and magnesium in sea water

An improved potentiometric titration method for the determination of calcium and magnesium in sea water has been newly devised. In this method, a mini-computer is used for the automation of titrations, and ion-selective electrodes are used as an end-point detector. Calcium is determined by titration with EGTA, and total alkaline earth metals (magnesium + calcium + strontium) by titration with EDTA. Magnesium can be determined by the difference, strontium having been determined by a suitable method. In the present method, calcium and magnesium in sea water can be determined with a precision of 0.1 %.

The determination of Mn, Fe, Ni, Cu and Zn in seawater by atomic absorption spectrometry after coprecipitation with lanthanum hydroxide

A simple and rapid coprecipitation method for the determination of several trace metals in seawater is presented. These metals are coprecipitated with lanthanum hydroxide, the precipitate is dissolved, and then the metals are determined by atomic absorption spectrometry. Lanthanum hydroxide was chosen as a coprecipitant for the following reasons, (a) lanthanum hydroxide has a sufficiently low solubility and forms an easily filterable flocculate at about 80‡C, and (b) lanthanum has an absorption wavelength that is sufficiently separated from those of the other elements to be analysed, i.e., Mn, Fe, Ni, Cu and Zn. Experimental results show that these metals are coprecipitated by the present method with excellent recoveries.

The reversible effect of temperature on the chemical composition of interstitial water of marine sediment

The reversibility of the temperature effect on the chemical composition of interstitial waters of three deep-sea sediment samples was examined between 2 and 25°C for Cl, Na, K, Mg, Ca, Si, B, Mn and alkalinity. When the temperature of sediment samples was returned from 25°C to the initial value of 2°C, most chemical species gave nearly their initial concentrations. However, for alkalinity and in one case for magnesium, it took another three to four hours to reach their initial concentrations.

Calcium-alkalinity-nitrate relationship in the north pacific and the Japan Sea

When biogenic particles of calcium carbonate and organic matter are formed or decomposed in sea water, calcium concentration, alkalinity and nitrate concentration are changed according to the following equation: ΔCa=0.5 ΔTA+0.63 ΔNO3, where ΔCa, ΔTA and ΔNO3 are the differences in calcium, alkalinity and nitrate concentration, respectively, between two waters. This relationship was pointed out in a previous paper of ours, and it holds well for data obtained from the North Pacific and the Japan Sea. Furthermore, in sea water containing little or no nutrients, the variations in calcium concentration and alkalinity are consistent with the variations expected from the formation and dissolution of calcium carbonate alone.

Shipboard calibration of an infrared absorption gas analyser for total carbon dioxide determination in sea water

A new method for shipboard calibration of an infrared absorption carbon dioxide analyser was devised, utilizing the oxidative decomposition reaction of oxalic acid by permanganate in acid solution. With the present method, shipboard analysis of total carbon dioxide in 2 ml of sea water can be carried out with an error of less than 0.5 %. Some improvements in the analyser system are also presented.

Chemical modification of sea water by submarine volcanism at Nishinoshima-Shintô Island

Sea water samples, still hot from volcanic emanations were taken in a bay of Nishinoshima-Shintô Island just after volcanic activity had ceased and were analysed for borate-B, fluoride-F and bromide-Br. The hot water is considered to be formed by the conservative mixing of volcanic emanations with sea water, and the emanations containedCl, B, F andBr in the ratio of 1∶1.84×10−3∶0.474×10−3∶6.47×10−3 by weight.RatiosB/Cl andF/Cl can be used as effective measures of the contribution of volcanic emanations to sea water.