Comprehensive Archaeological and Palaeoecological Studies of the Holocene Chronosequence in the Southern Taiga of the Middle Yenisei

The article presents the results of a comprehensive interdisciplinary analysis of archaeological and palaeoecological data. The aim of the study was to identify climatic changes in the habitat and their impact on the formation of the palaeoeconomics of the ancient population, on the expansion or reduction of the area of archaeological cultures with foraging and producing economy. Based on the analysis of palaeosignals obtained by a complex of methods (pollen, botanical analysis of peat, charcoal analysis, determination of the ash content of sediments), the following intervals of changing conditions were identified: 7400—6800 calibrated years before present (cal. BP) — humidity reduction, 4850—4400 cal. BP — an increase in humidity, 3850—3150 cal. BP — decrease in humidity, 3150—2000 cal. BP — stable humid, with 1600 cal. BP — moisture reduction, 1250—700 cal. BP — minimal moisture. Changes in conditions are consistent with changes in the boundaries of the subzone of the southern taiga and forest-steppe, as well as with the range of cultures of Siberian hunters, fishers, gatherers and pastoralists. The results can be projected over the entire Siberian region.

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A novel method for the determination of linting propensity of paper

TAPPI Journal ◽

10.32964/tj11.10.9 ◽

2012 ◽

Vol 11 (10) ◽

pp. 9-17

Author(s):

ALESSANDRA GERLI ◽

LEENDERT C. EIGENBROOD

Keyword(s):

Ash Content ◽

The Novel ◽

Offset Printing ◽

Excellent Correlation ◽

End Conditions ◽

Bottom Side ◽

Novel Method ◽

Total Fraction

A novel method was developed for the determination of linting propensity of paper based on printing with an IGT printability tester and image analysis of the printed strips. On average, the total fraction of the surface removed as lint during printing is 0.01%-0.1%. This value is lower than those reported in most laboratory printing tests, and more representative of commercial offset printing applications. Newsprint paper produced on a roll/blade former machine was evaluated for linting propensity using the novel method and also printed on a commercial coldset offset press. Laboratory and commercial printing results matched well, showing that linting was higher for the bottom side of paper than for the top side, and that linting could be reduced on both sides by application of a dry-strength additive. In a second case study, varying wet-end conditions were used on a hybrid former machine to produce four paper reels, with the goal of matching the low linting propensity of the paper produced on a machine with gap former configuration. We found that the retention program, by improving fiber fines retention, substantially reduced the linting propensity of the paper produced on the hybrid former machine. The papers were also printed on a commercial coldset offset press. An excellent correlation was found between the total lint area removed from the bottom side of the paper samples during laboratory printing and lint collected on halftone areas of the first upper printing unit after 45000 copies. Finally, the method was applied to determine the linting propensity of highly filled supercalendered paper produced on a hybrid former machine. In this case, the linting propensity of the bottom side of paper correlated with its ash content.

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Energetic properties of peat saturated with petroleum products

Safety and Reliability of Power Industry ◽

10.24223/1999-5555-2020-13-2-105-109 ◽

2020 ◽

Vol 13 (2) ◽

pp. 105-109

Author(s):

E. S. Dremicheva

Keyword(s):

Crude Oil ◽

Diesel Fuel ◽

Energy Use ◽

Experimental Studies ◽

Calorific Value ◽

Petroleum Products ◽

Ash Content ◽

Motor Oil ◽

Initial Sample

This paper presents a method of sorption using peat for elimination of emergency spills of crude oil and petroleum products and the possibility of energy use of oil-saturated peat. The results of assessment of the sorbent capacity of peat are presented, with waste motor oil and diesel fuel chosen as petroleum products. Natural peat has been found to possess sorption properties in relation to petroleum products. The sorbent capacity of peat can be observed from the first minutes of contact with motor oil and diesel fuel, and significantly depends on their viscosity. For the evaluation of thermal properties of peat saturated with petroleum products, experimental studies have been conducted on determination of moisture and ash content of as-fired fuel. It is shown that adsorbed oil increases the moisture and ash content of peat in comparison with the initial sample. Therefore, when intended for energy use, peat saturated with petroleum products is to be subjected to additional drying. Simulation of net calorific value has been performed based on the calorific values of peat and petroleum products with different ratios of petroleum product content in peat and for a saturated peat sample. The obtained results are compared with those of experiments conducted in a calorimetric bomb and recalculated for net calorific value. A satisfactory discrepancy is obtained, which amounts to about 12%. Options have been considered providing for combustion of saturated peat as fuel (burnt per se and combined with a solid fuel) and processing it to produce liquid, gaseous and solid fuels. Peat can be used to solve environmental problems of elimination of emergency spills of crude oil and petroleum products and as an additional resource in solving the problem of finding affordable energy.

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