Alteration of Chemical Composition of Fossil Bones by Soil Processes and Groundwater

The investigation I am about to bring before the Royal Society, was undertaken in consequence of a discussion which took place in the Zoological Society of London in 1843, in reference to the chemical composition of the bones of the gigantic bird the Dinornis, discovered some time previously in New Zealand. At the meeting in question, the distinguished palæontologist Dr Falconer drew attention to the frequent, if not constant, occurrence of fluoride of calcium in fossil bones, and, as he stated, also in those of mummies; and threw out the suggestion, that the fluoride might shew itself in these animal remains, not as an original ingredient of the bones, or as derived from the matrix in which they were found, but as a product of the transmutation of their phosphate of lime. The idea of such a conversion taking place, is as old at least as the days of Klaproth, who suggested the possibility of phosphoric acid becoming changed into fluoric. It is commented upon by Fourcroy and Vauquelin, as well as by Gay Lussac, as a thing possible but not probable, and which their ignorance of the nature of fluoric acid prevented them from discussing satisfactorily.

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Assemblage Data and Bone and Teeth Modifications as an Aid to Paleoenvironmental Interpretations of the Open-Air Pleistocene Site of Tighenif (Algeria)

Quaternary Research ◽

10.1006/qres.1994.1084 ◽

1994 ◽

Vol 42 (3) ◽

pp. 340-349 ◽

Cited By ~ 20

Author(s):

Yannicke Dauphin ◽

Casimir Kowalski ◽

Christiane Denys

Keyword(s):

Chemical Composition ◽

Fossil Record ◽

Climatic Changes ◽

Skeletal Remains ◽

Complex Interaction ◽

Fossil Bones

AbstractVariations in the proportions of the various groups of Rodentia collected from eight stratigraphic levels at Tighenif had previously been interpreted as representing environmental (climatic) changes. However, the processes involved in the formation of assemblages are still not well understood. Examination of fragmentation, crystallinity, and chemical composition of fossil bones and teeth, compared to recent samples, shows that a possible explanation for the variations in frequencies is the differential preservation of skeletal remains. Thus, the evaluation of postmortem effects is essential in determining the accuracy of the fossil record. The abundance and composition of remains are governed by the complex interaction of many factors. As indicated by actualistic studies, direct deductions from fauna lists must be avoided as much as possible.

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Diagnostic problems of elementary soil processes and profile-differentiated soils of the Precarpathian region

Fundamental and Applied Soil Science ◽

10.15421/041604 ◽

2016 ◽

Vol 17 (1-2) ◽

pp. 40-48

Author(s):

I. S. Smaga

Keyword(s):

Chemical Composition ◽

Soil Properties ◽

Diagnostic Criteria ◽

Humic Acids ◽

Soil Type ◽

Soil Profile ◽

Laboratory Simulation ◽

Soil Processes ◽

Acid Base ◽

Genetic Nature

Present condition, scientific concepts and ways of further development of diagnosis problem of elementary soil processes and genetic nature profiled-differentiated gleyed soils of the Pre-Carpathian region, known as brownish-podzolic, brownsoil-podzolic and sod-podzolic, based on stable indicators of soil properties are studied. Eluvial-illuvial differentiation nature of the soil profile of the studied soils is founded. The aim of research was to develop criteria for the diagnosis of elementary soil processes and genetic nature profiled-differentiated soil deposits of Ciscarpathia and discovering of the parameters of the relevant indicators of soil properties. The soil profile with his characteristic set of genetic horizons and morphological characteristics can result from taking place of both various set (kit) of ESP and of varying intensity of individual processes (complex ESP). Formation of genetic soil type is caused by the course of the profile forming (main) process with the possible participation of several (related) processes. An important condition for the diagnostic determination of profile-differentiated soils in the Ciscarpathia is the search for reliable diagnostic criteria for basic elementary soil processes (ESP) which play a crucial role in the genesis and determine their macromorphological characteristics: lessivage, podzolisation, gleying and eluvial-gleying processes. Diagnostic criteria of the elluvial processes resulted in gross chemical composition of the soil (molecular ratio), particle size distribution (loss sludge) and mineralogy silt fraction (montmorillonite content) were tested. The criteria for establishing genetic origin of the Pre-Carpathian soils, podzolization and eluvial-gley processes detection and their possible parameters were suggested. Followed the impact of the prevailing development of individual creating profile elementary soil processes (podzolization, eluvial-gley and gleying) by laboratory simulation modeling of soil regimes that are conducive to them (washing, water stagnant and contrast) for evaluative indicators of acid-base soil buffer and made the conclusions about the possibility of these processes isolation. Eluvial-illuvial differentiation of Ciscarpathia typical soils is coursed by passage of profile forming process of podzolisation (acid hydrolysis, podzolic) and related from the group of eluvial - eluvial-gleying process and lessivage. They are diagnosed by the gross grain and chemical composition of the soil and the content of montmorillonite. Brown soil forming processes have a significant impact on the formation of humus status and physical and chemical properties of the studied soil. Substantiated differences forming the group composition of humus and fractional composition of humic acids of soils formed underbrownsoil formation processes from the sod soils type (the ratio of humic acids to fulvic acid, gumatcalcium content, optical density of humic substances). Advantages and disadvantages of using quantitative identification criteria - profile humus accumulation factor in the genetic diagnosis of soil type are analyzed. In the conditions of wash and contrasting modes of moisture, causing the priority development processes of podzolisation and gleye- eluvial respectively a similar trend of formation of acid-base buffer capacity of soil and similar parameters of evaluating indicators within the soil profile are observed. It is impossible to separate the processes of podzolisation and gleye- eluvial using the indicators of acid-base buffering. Describing of profile structure, morphological and genetic traits of genetic horizons, the profile distribution of acid-base buffering indicators (even without the use of criteria based on gross chemical and grain composition and content of clay minerals) help to clear identify brownish-podzolic gley soils of Ciscarpathia.

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The Origin of the Moon

Symposium - International Astronomical Union ◽

10.1017/s0074180900178209 ◽

1962 ◽

Vol 14 ◽

pp. 149-155 ◽

Cited By ~ 1

Author(s):

E. L. Ruskol

Keyword(s):

Chemical Composition ◽

Solar System ◽

The Moon ◽

The Earth ◽

The Difference ◽

Origin Of The Moon

The difference between average densities of the Moon and Earth was interpreted in the preceding report by Professor H. Urey as indicating a difference in their chemical composition. Therefore, Urey assumes the Moon's formation to have taken place far away from the Earth, under conditions differing substantially from the conditions of Earth's formation. In such a case, the Earth should have captured the Moon. As is admitted by Professor Urey himself, such a capture is a very improbable event. In addition, an assumption that the “lunar” dimensions were representative of protoplanetary bodies in the entire solar system encounters great difficulties.

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On the Inhomogeneity of Chemical Composition over the Surface of 21 Per

International Astronomical Union Colloquium ◽

10.1017/s0252921100080659 ◽

1976 ◽

Vol 32 ◽

pp. 343-349

Author(s):

Yu.V. Glagolevsky ◽

K.I. Kozlova ◽

V.S. Lebedev ◽

N.S. Polosukhina

Keyword(s):

Chemical Composition ◽

Spectral Line ◽

Variable Star ◽

Radial Velocities ◽

Crimean Astrophysical Observatory ◽

Line Intensities ◽

Magnetic Variable

SummaryThe magnetic variable star 21 Per has been studied from 4 and 8 Å/mm spectra obtained with the 2.6 - meter reflector of the Crimean Astrophysical Observatory. Spectral line intensities (Wλ) and radial velocities (Vr) have been measured.

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Structural Studies on Mitotic Spindle Fibres

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100070345 ◽

1978 ◽

Vol 36 (3) ◽

pp. 615-626

Author(s):

J.R. Mcintosh

Keyword(s):

Chemical Composition ◽

Mitotic Spindle ◽

Structural Studies ◽

Mitotic Apparatus ◽

Chemical Studies ◽

Medical Interest ◽

Spindle Fibres

The mitotic apparatus is a structure of obvious biological and medical interest, but it has proved to be a difficult cellular machine to understand. The chemical composition of the spindle is only slightly elucidated, largely because of the difficulties in preparing useful isolates of the structure. Chemical studies of the mitotic spindle have been reviewed elsewhere (Mcintosh, 1977), and will not be discussed further here. One would think that structural studies on the mitotic apparatus (MA) in situ would be straightforward, but even with this approach there is some disagreement in the results obtained with various methods and by different investigators. In this paper I will review briefly the approaches which have been used in structural studies of the MA, pointing out the strengths and problems of each approach. I will summarize the principal findings of the different methods, and identify what seem to be fruitful avenues for further work.

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Effects of 5-5'-Diphenyl-2-thiohydantoin (DPTH) and Thyroxine on the Ultrastructure and Chemical Composition of Rat Liver

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100066917 ◽

1971 ◽

Vol 29 ◽

pp. 570-571

Author(s):

E. A. Elfont ◽

R. B. Tobin ◽

D. G. Colton ◽

M. A. Mehlman

Keyword(s):

Chemical Composition ◽

Rat Liver ◽

Future Study ◽

Mode Of Action ◽

Liver Mitochondria ◽

Rat Liver Mitochondria ◽

Effective Inhibitor ◽

Biochemical Effects ◽

Glycerophosphate Dehydrogenase ◽

Stimulation Of

Summary5,-5'-diphenyl-2-thiohydantoin (DPTH) is an effective inhibitor of thyroxine (T4) stimulation of α-glycerophosphate dehydrogenase in rat liver mitochondria. Because this finding indicated a possible tool for future study of the mode of action of thyroxine, the ultrastructural and biochemical effects of DPTH and/or thyroxine on rat liver mere investigated.Rats were fed either standard or DPTH (0.06%) diet for 30 days before T4 (250 ug/kg/day) was injected. Injection of T4 occurred daily for 10 days prior to sacrifice. After removal of the liver and kidneys, part of the tissue was frozen at -50°C for later biocheailcal analyses, while the rest was prefixed in buffered 3.5X glutaraldehyde (390 mOs) and post-fixed in buffered 1Z OsO4 (376 mOs). Tissues were embedded in Araldlte 502 and the sections examined in a Zeiss EM 9S.Hepatocytes from hyperthyroid rats (Fig. 2) demonstrated enlarged and more numerous mitochondria than those of controls (Fig. 1). Glycogen was almost totally absent from the cytoplasm of the T4-treated rats.

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Applications of Photoelectron Microscopy

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100092499 ◽

1976 ◽

Vol 34 ◽

pp. 506-507

Author(s):

William J. Baxter

Keyword(s):

Electron Microscopy ◽

Thermal Decomposition ◽

Chemical Composition ◽

Ultraviolet Radiation ◽

Thin Layer ◽

Edge Effects ◽

Electron Optics ◽

Surface Layers ◽

Crystalline Orientation ◽

Fluorescent Screen

In this form of electron microscopy, photoelectrons emitted from a metal by ultraviolet radiation are accelerated and imaged onto a fluorescent screen by conventional electron optics. image contrast is determined by spatial variations in the intensity of the photoemission. The dominant source of contrast is due to changes in the photoelectric work function, between surfaces of different crystalline orientation, or different chemical composition. Topographical variations produce a relatively weak contrast due to shadowing and edge effects.Since the photoelectrons originate from the surface layers (e.g. ∼5-10 nm for metals), photoelectron microscopy is surface sensitive. Thus to see the microstructure of a metal the thin layer (∼3 nm) of surface oxide must be removed, either by ion bombardment or by thermal decomposition in the vacuum of the microscope.

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