ABSTRACT
The process of Near Eastern neolithization and its westward expansion from the core zone in the Levant and upper Mesopotamia has been broadly discussed in recent decades, and many models have been developed to describe the spread of early farming in terms of its timing, structure, geography and sociocultural impact. Until now, based on recent intensive investigations in northwestern and western Anatolia, the discussion has mainly centred on the importance of Anatolian inland routes for the westward spread of neolithization. This contribution focuses on the potential impact of east Mediterranean and Aegean maritime networks on the spread of the Neolithic lifestyle to the western edge of the Anatolian subcontinent in the earliest phases of sedentism. Employing the longue durée model and the concept of 'social memory', we will discuss the arrival of new groups via established maritime routes. The existence of maritime networks prior to the spread of farming is already indicated by the high mobility of Epipalaeolithic/Mesolithic groups exploring the Aegean and east Mediterranean seas, and reaching, for example, the Cyclades and Cyprus. Successful navigation by these early mobile groups across the open sea is attested by the distribution of Melian obsidian. The potential existence of an additional Pre-Pottery Neolithic (PPN) obsidian network that operated between Cappadocia/Cilicia and Cyprus further hints at the importance of maritime coastal trade. Since both the coastal and the high seas networks were apparently already well established in this early period, we may further assume appropriate knowledge of geographic routes, navigational technology and other aspects of successful seafaring. This Mesolithic/PPN maritime know-how package appears to have been used by later groups, in the early 7th millennium calBC, exploring the centre of the Anatolian Aegean coast, and in time establishing some of the first permanent settlements in that region. In the present paper, we link this background of newcomers to the western edge of Anatolia with new excavation results from Çukuriçi Höyük, which we have analysed in terms of subsistence strategies, materiality, technology and symbolism. Additionally, further detailed studies of nutrition and obsidian procurement shed light on the distinct maritime affinity of the early settlers in our case study, something that, in our view, can hardly be attributed to inland farming societies. We propose a maritime colonization in the 7th millennium via routes from the eastern Mediterranean to the eastern Aegean, based on previously developed sea networks. The pronounced maritime affinity of these farming and herding societies allows us to identify traces of earlier PPN concepts still embedded in the social-cultural memories of the newcomers and incorporated in a new local and regional Neolithic identity.
ABSTRACT
Extraction of Prussian Blue into chloroform in the presence of ajatin (dimethyl-lauryl-benzylammonium bromide) is proposed for the concentration and determination of ferrocyanide ion. Optimum concentrations of sulphuric acid and of ajatin have been established and the selectivity of the extraction has been investigated. Ways of eliminating some interferences are discussed.
ABSTRACT
An investigation of the possibilities of the use of di-2-naphthylthiocarbazone as titrant in spectrophotometric extractive titrations has been undertaken. A selective procedure for successive titration of silver in an ammoniacal medium has been developed and applied to the analysis of germanium dioxide. It has been established that the consecutive titration of mercury and zinc in the microgram range is possible. Because of low selectivity of this titration, a separation of mercury and zinc from other ions is necessary.
ABSTRACT
The possibility of using PAN as a titrant in spectrophotometric extractive titrations has been investigated. Conditions suitable for the titration of zinc and of cadmium were found, with the aid of equations derived earlier and after investigation of the absorption spectra and pH- and reagent-dependence of the extraction of the chelates involved. For the purpose of spectrophotometric extractive titration of copper with PAN the formation and extraction of ion-association pairs CuPAN(+).Br(-) and CuPAN(+).CNS(-) were studied in detail. This titration was found to be highly selective. Dilute solutions of PAN in ethanol are much more stable than solutions of dithizone.
ABSTRACT
The general equation of the titration curve for spectro-photometric extractive titrations is derived. The graphical location of the end-point is assumed and the significance of the general equation is discussed. Simple formulas for threshold pH and for sensitivity are obtained. An increased selectivity of spectrophotometric extractive titrations in comparison with that of the usual spectrophotometric extractive methods is demonstrated.
ABSTRACT
A simple and selective determination of zinc in germanium chloride and germanium dioxide is described. The sample is dissolved in sodium potassium tartrate solution and zinc is titrated spectrophotometrically at 532 mug( with a dithizone solution in carbon tetrachloride without discarding the organic phase. Interfering ions such as Bi(III), Cu(II), Cd(II), Co(II), Ni(II), Pb(II), Sn(II), Fe(II), Fe(III), Mn(II) and T1(I) are masked with bis(2-hydroxyethyl)dithiocarbamate. The detection limit is 3-23 x 10(-5)% of zinc and this may be lowered by taking a larger sample and by performing the analysis in a closed system. A simplified technique, consisting of the simultaneous titration of the sample and blank, is described.
ABSTRACT
A procedure for the simultaneous determination of silver and copper in high-purity lead is given. After dissolution of the sample the majority of the lead is removed by precipitation with ammonium sulphate. Silver and copper are then determined by spectrophotometric extractive titration at pH 4.3-5.5 with dithizone. Changes of absorbance are measured at 550 mmu. The procedure has been checked by the method of standard additions and by comparison with conventional methods. The procedure is highly selective. The limit of determination is 2.5 x 10(-5)% of silver and 1.1 x 10(-5)% of copper.
ABSTRACT
A procedure for the determination of the sum of metals, which are extractable with dithizone, in gallium arsenide is given. After the dissolution of the sample the impurities are extracted with several portions of 10(-4)M dithizone in carbon tetrachloride, gallium being screened by tartrate ion. The excess of the reagent is extracted into 0.1M aqueous ammonia and after stripping into carbon tetrachloride the dithizone is determined by spectrophotometric extractive titration. The effect of pH is considered. The limit of detection, based on the evaluation of twenty blanks, is 2.30 x 10(-8) mole, the equivalent of 1.50 mug of zinc.
ABSTRACT
A modification of extractive titrations, spectrophotometric end-point determination, is proposed. There is no need to discard the organic layer after each extraction because specially constructed titration cells are used. Precise, rapid and selective determination of microgram amounts of single cations, and in favourable cases pairs of cations, is possible.
