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The metrological support of optoelectronic instruments for measuring spatial coordinates is described. In order to meet current consumer requirements for accuracy in measuring spatial coordinates with electronic total stations and their counterparts (laser scanners; absolute trackers), GET 199-2024 State primary special standard of the unit of length includes technical means of reproducing, maintaining, and disseminating the unit of length in three-dimensional measurement mode. A standard three-dimensional measurement system (coordinate measurements; coordinate increments) was developed and studied. The means and methods for disseminating the unit of length in coordinate (length) increment measurement mode are presented, as well as the metrological characteristics of GET 199-2024. The sources of the residual systematic error and the standard deviation of the measurement result were determined. The conducted study enabled a reproduction of the unit of length in the mode of measuring coordinate increments within the range of 0–60 m with the standard deviation not exceeding 25 μm at ten independent measurements and a residual systematic error (at a confidence level of 0.99) of 19 μm. The functional capabilities of GET 199-2024 will provide a means to solve relevant problems associated with the metrological support of high-precision electronic total stations and their counterparts in three-dimensional measurement mode. [ABSTRACT FROM AUTHOR]

The emergence of pottery in Europe is associated with two distinct traditions: hunter-gatherers in the east of the continent during the early 6th millennium BC and early agricultural communities in the south-west in the late 7th millennium BC. Here we investigate the function of pottery from the site of Rakushechny Yar, located at the Southern fringe of Eastern Europe, in this putative contact zone between these two economic ‘worlds’. To investigate, organic residue analysis was conducted on 120 samples from the Early Neolithic phase (ca. mid-6th millennium BC) along with microscopic and SEM analysis of associated foodcrusts. The results showed that the earliest phase of pottery use was predominantly used to process riverine resources. Many of the vessels have molecular and isotopic characteristics consistent with migratory fish, such as sturgeon, confirmed by the identification of sturgeon bony structures embedded in the charred surface deposits. There was no evidence of dairy products in any of the vessels, despite the fact these have been routinely identified in coeval sites to the south. Further analysis of some of the mammalian bones using ZooMS failed to demonstrate that domesticated animals were present in the Early Neolithic. Nevertheless, we argue that intensive exploitation of seasonally migratory fish, accompanied by large-scale pottery production, created storable surpluses that led to similar socio-economic outcomes as documented in early agricultural societies. [ABSTRACT FROM AUTHOR]

Two kinds of samples of Early and Late Neolithic ceramic sherds of pots from excavations of sites located in Dnepr–Dvina and Low Don region (Serteya II and Rakushechny Yar) were investigated for multi-analytical comparison. The methods include thermogravimetric analysis, X-ray powder diffraction, X-ray photoelectron spectroscopy and method of standard contact porosimetry. The pottery manufactured in Serteya II and Rakushechny Yar has different clay sources, but close mineral composition. Inner sides of sherds are less thermally durable as a result of the contact with cooking meal or boiling water in ancient times: They lose more mass during thermogravimetric measurements. At the same time, the minerals in outer sides of the samples are partly destroyed because of contact with fire in the past. According to differential scanning calorimetry curves, there are thermal effects above 1000 °C in all sherds due to mullite formation. There are organic C–F bonds and sharp endothermic peaks at 600–750 °C in samples from Serteya II site. In addition to elevated level of nitrogen and phosphorus and carbon black layer on the inner side, it allows to propose that the pot from Serteya II was used for cooking. The sherds from both sites have close overall porosity, but in case of Serteya II size of mesopore is more isotropic. [ABSTRACT FROM AUTHOR]