scholarly journals These boots are made for burnin’: Inferring the position of the corpse and the presence of leather footwears during cremation through isotope (δ13C, δ18O) and infrared (FTIR) analyses of experimentally burnt skeletal remains

PLoS ONE ◽  
2021 ◽  
Vol 16 (10) ◽  
pp. e0257199
Author(s):  
Kevin Salesse ◽  
Elisavet Stamataki ◽  
Ioannis Kontopoulos ◽  
Georges Verly ◽  
Rica Annaert ◽  
...  
Keyword(s):  
Soft Tissues ◽  
Protective Layer ◽  
Shielding Effect ◽  
Mortuary Practice ◽  
Oxygen Isotope Ratios ◽  
Initial Location ◽  
Heat Shielding ◽  
Favorable Conditions ◽  
Calcined Bone ◽  
Bone Apatite

Cremation is a complex mortuary practice, involving a number of activities of the living towards the dead before, during, and after the destruction of the bodily soft tissues by fire. The limiting information concerning these behavioral patterns obtained from the pyre remains and/or cremation deposits prevents the reconstruction of the handling of the corpse during the burning process. This pioneering study tries to determine the initial positioning of the corpse in the pyre and assess whether the deceased was wearing closed leather shoes during cremation through isotopic (δ13C, δ18O) and infrared (ATR-FTIR) analyses of experimentally burnt pig remains, used as a proxy for humans. The results obtained show that both the position of feet on or within the pyre and the presence of footwears may moderately-to-highly influence the oxygen isotope ratios of bone apatite carbonates and the cyanamide content of calcined bone in certain situations. By forming a protective layer, shoes appear to temporarily delay the burning of the underlying pig tissues and to increase the heat-shielding effect of the soft tissues protecting the bone mineral fraction. In such case, bioapatite bone carbonates exchange oxygen with a relatively more 18O-depleted atmosphere (due to the influence of lignin-derived oxygen rather than cellulose-derived oxygen), resulting in more pronounced decrease in the δ18Ocarb values during burning of the shoed feet vs. unshoed feet. The shift observed here was as high as 2.5‰. A concomitant isotopic effect of the initial location of the feet in the pyres was also observed, resulting in a top-to-bottom decrease difference in the δ18Ocarb values of shoed feet of about 1.4‰ between each deposition level tested. Finally, the presence of cyanamide (CN/P ≥ 0.02) seems to be indicative of closed footwear since the latter creates favorable conditions for its incorporation into bone apatite.

scholarly journals Optimum Heat Shielding Effect of an Engine by using Aluminium, Zirconium Materials

2019 ◽  
Vol 8 (12) ◽  
pp. 1479-1485
Keyword(s):  
Shielding Effect ◽  
Heat Shields ◽  
Optimum Heat ◽  
Heat Shielding

A warmth shield is intended to shield a substance from retaining extreme warmth from an outside source by either dispersing, reflecting or basically engrossing the warmth. Because of the a lot of warmth radiated by inward burning motors, heat shields are utilized on most motors to shield segments and bodywork from warmth. Just as assurance, compelling warmth shields can give a presentation advantage by lessening the under-cap temperatures, accordingly decreasing the admission temperature. Warmth protecting is important to avert motor warmth from harming heat-delicate parts. Most of more established vehicles utilize straightforward steel warmth protecting to diminish warm radiation and convection. Itis currently most regular for present day vehicles are to utilize aluminum warmth protecting which has a lower thickness, can be effectively shaped and does not erode similarly as steel. Higher execution vehicles are starting to utilize fired warmth protecting as this can withstand far higher temperatures just as further decreases in warmth move.

Carbon Exchanges between Bone Apatite and Fuels during Cremation: Impact on Radiocarbon Dates

Radiocarbon ◽  
2014 ◽  
Vol 56 (2) ◽  
pp. 591-602 ◽  
Author(s):  
C Snoeck ◽  
F Brock ◽  
R J Schulting
Keyword(s):  
Carbon Isotopic Composition ◽  
Important Advance ◽  
Natural Conditions ◽  
Radiocarbon Dates ◽  
Archaeological Material ◽  
Carbon Isotopic ◽  
Calcined Bone ◽  
Crucial Part ◽  
Bone Apatite ◽  
Fuel Source

An important advance in the radiocarbon dating of archaeological material occurred in the late 1990s, with direct dating of cremated human remains. A crucial part of the argument was the demonstration that comparable results could be obtained from paired dates of charcoal and calcined bone from the same contexts. Recent studies, however, have noted the influence of carbon from the fuel sources, raising a question over the interpretation of the paired charcoal/bone dates. Here, fleshed modern animal joints were burned with “old” fuel of known age, providing experimental evidence under natural conditions, demonstrating a clear effect of the fuel source on the carbon isotopic composition of calcined bone. In most situations in which branchwood was used as fuel, dates on calcined bone should not show any significant offset, as the wood will be of a similar age to the cadaver. For cases in which old wood, coal, or peat are used as fuel, we expect an offset of some decades/centuries, potentially up to millennia. We observed, however, that the amount of14C intake from the fuel is extremely variable (from 39 to 95%). A strong correlation between age offset and δ13C values suggests that the latter might be useful in identifying large inputs from14C-depleted fuels. A level of caution is recommended when14C dating calcined bone in cases where fuels with an inbuilt age may have been used in the cremation process.

Carbon Exchanges between Bone Apatite and Fuels during Cremation: Impact on Radiocarbon Dates

Radiocarbon ◽  
2014 ◽  
Vol 56 (02) ◽  
pp. 591-602 ◽  
Author(s):  
C Snoeck ◽  
F Brock ◽  
R J Schulting
Keyword(s):  
Carbon Isotopic Composition ◽  
Important Advance ◽  
Natural Conditions ◽  
Radiocarbon Dates ◽  
Archaeological Material ◽  
Carbon Isotopic ◽  
Calcined Bone ◽  
Crucial Part ◽  
Bone Apatite ◽  
Fuel Source

An important advance in the radiocarbon dating of archaeological material occurred in the late 1990s, with direct dating of cremated human remains. A crucial part of the argument was the demonstration that comparable results could be obtained from paired dates of charcoal and calcined bone from the same contexts. Recent studies, however, have noted the influence of carbon from the fuel sources, raising a question over the interpretation of the paired charcoal/bone dates. Here, fleshed modern animal joints were burned with “old” fuel of known age, providing experimental evidence under natural conditions, demonstrating a clear effect of the fuel source on the carbon isotopic composition of calcined bone. In most situations in which branchwood was used as fuel, dates on calcined bone should not show any significant offset, as the wood will be of a similar age to the cadaver. For cases in which old wood, coal, or peat are used as fuel, we expect an offset of some decades/centuries, potentially up to millennia. We observed, however, that the amount of14C intake from the fuel is extremely variable (from 39 to 95%). A strong correlation between age offset and δ13C values suggests that the latter might be useful in identifying large inputs from14C-depleted fuels. A level of caution is recommended when14C dating calcined bone in cases where fuels with an inbuilt age may have been used in the cremation process.

scholarly journals Can we Use Calcined Bones for 14C Dating the Paleolithic?

Radiocarbon ◽  
2013 ◽  
Vol 55 (3) ◽  
pp. 1409-1421 ◽  
Author(s):  
Antoine Zazzo ◽  
Matthieu Lebon ◽  
Laurent Chiotti ◽  
Clothilde Comby ◽  
Emmanuelle Delqué-Količ ◽  
...  
Keyword(s):  
Bone Collagen ◽  
Clear Correlation ◽  
14C Dating ◽  
Splitting Factor ◽  
Minimum Age ◽  
C Value ◽  
Almost All ◽  
Calcined Bone ◽  
Bone Apatite ◽  
Different Levels

This work aims to test the reliability of calcined bones for radiocarbon dating of the Paleolithic. Fifty-five calcined bone samples coming from Aurignacian and Gravettian layers at Abri Pataud (Dordogne, France) were selected based on their macroscopic features. For each sample, the heating state was estimated on the basis of bone crystallinity (splitting factor [SF] using FTIR) and δ13C value. Twenty-seven bone samples (3 unburnt and 24 calcined) from 5 different levels were prepared for 14C dating. The majority (15/24) of the calcined samples had to undergo a sulfix treatment prior to graphitization, probably due to the presence of cyanamide ion in these samples. The comparison between our results and recently published dates on bone collagen for the same levels shows that unburned bone apatite is systematically too young, while a third of the calcined bones fall within or very near the range of expected age. No clear correlation was found between 14C age offset and δ13C value or SF. Most of the sulfixed samples (14/16) yielded ages that were too young, while almost all of the non-sulfixed samples (8/9) gave ages similar or <0.2 pMC from the expected minimum age. Although preliminary, these results suggest that sulfix should be avoided if possible and that clean CO2 gas from well-calcined Paleolithic bones can provide reliable 14C ages.

scholarly journals ASSESSMENT OF THE INFLUENCE OF THE HEAT SHIELDING EFFECT OF OILS ON THE POSSIBILITY OF JAMMING IN THE MOBILE INTERFACES OF TRANSPORT VEHICLES

2020 ◽  
Vol 8 (1) ◽  
pp. 135-139
Author(s):  
Dmitriy Popov ◽  
M. Rudik ◽  
A. Podzolkov
Keyword(s):  
Theoretical Calculations ◽  
Thermal Capacity ◽  
Shielding Effect ◽  
Material Density ◽  
Mobile Interfaces ◽  
Theoretical Assumptions ◽  
Empirical Tests ◽  
Heat Shielding ◽  
Boundary Films

the influence of the heat-shielding effect of oils on the occurrence of wear in mobile interfaces during jamming, characterized by such a defect as a bully and accompanied by the transfer of metal from one friction surface to another, is analyzed. The research was carried out both on the basis of theoretical calculations based on the thermodynamic theory of friction, and empirical tests using the developed device for simulating a temperature flash on a stationary friction contact and subsequent observation of the propagation of the heat flow according to the indications of thermocouples. On the basis of theoretical assumptions, and the results of the research, the hypothesis that the heat energy released as the result of frictional interactions at microscopic contact, has a high density and is spread with considerable speed mainly in the direction with the lowest thermal resistance due to the thermophysical characteristics of the material (density, conductivity) and thermal capacity, for example, thin boundary films (oil, oxide, servovite, sputtered, etc.) with a thickness of 1 µm and is comparable with the height of asperities. The results of the research confirm the hypothesis about the role of the heat-shielding effect of lubricants on the microcontact overheating and changes in the structure and properties of both the lubricant and the metal surface layer, which in turn cause increased wear of machine parts.

Sign in / Sign up

Export Citation Format

Share Document