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Geochemical characterisation and of black shales from the Tarfaya-Layoune Basin (SW Morocco) : Implications for palaeoenvironmental controls on sulfurisation process of the organic matter

REA Auditado

Organic geochemical and petrological investigations were carried out on
Cenomanian/Turonian black shales from three sample sites in the Tarfaya Basin (SW
Morocco) to characterize the sedimentary organic matter. These black shales have a
variable bulk and molecular geochemical composition reflecting changes in the quantity
and quality of the organic matter. High TOC contents (up to 18wt%) and hydrogen indices
between 400 and 800 (mgHC/gTOC) indicate hydrogen-rich organic matter (Type I-II
kerogen) which qualifies these laminated black shale sequences as excellent oil-prone
source rocks.

Tema: general: 

• Ciencias›Ciencias del Medio Ambiente

On the statistical mechanics of matter in an electromagnetic field. I. Derivation of the maxwell equations from electron theory

REA Auditado

Maxwell's macroscopic field equations are derived from the fundamental microscopic equations of electron theory in a new way. Instead of the usual space-time averaging procedure a statistical ensemble averaging method is applied, which is perhaps more satisfactory both from a physical and from a mathematical point of view. The treatment is valid for multicomponent systems, in which every component may move in an arbitrary way, so that e.g. diffusion phenomena are included.

Tema: general: 

• Ciencias Sociales›Educación

A new perspective on matter coupling in two-dimensional quantum gravity

REA Auditado

We provide compelling evidence that a previously introduced model of non-perturbative
2d Lorentzian quantum gravity exhibits (two-dimensional) flat-space behaviour
when coupled to Ising spins. The evidence comes from both a high-temperature
expansion and from Monte Carlo simulations of the combined gravity-matter system.
This weak-coupling behaviour lends further support to the conclusion that
the Lorentzian model is a genuine alternative to Liouville quantum gravity in two
dimensions, with a different, and much ‘smoother’ critical behaviour.

Tema: general: 

• Ciencias Sociales›Educación

Determinants of the proinflammatory action of ambient particulate matter in immortalized murine macrophages

REA Auditado

Background: Proximity to traffic-related pollution has been associated with poor respiratory health in adults and children.
Objectives: We wished to test the hypothesis that particulate matter (PM) from high-traffic sites would display an enhanced capacity to elicit inflammation.
Methods: We examined the inflammatory potential of coarse [2.5–10 μm in aerodynamic diameter (PM2.5–10)] and fine [0.1–2.5 μm in aerodynamic diameter (PM0.1–2.5)] PM collected from nine sites throughout Europe with contrasting traffic contributions.

Tema: general: 

• Ciencias Sociales›Educación

Controls on the molecular and carbon isotopic composition of organic matter deposited in a Kimmeridgian euxinic shelf sea: Evidence for preservation of carbohydrates through sulfurisation

REA Auditado

Thirteen samples from the Kimmeridge Clay Formation (KCF) in Dorset, covering all different lithologies, were studied using bulk and molecular geochemical and microscopical techniques. Our data show that the positive correlation between TOC and 13CTOC reported for shales (Huc et al., 1992) also holds for other lithologies (e.g., limestones) if we correct for dilution by carbonate (TOC*).

Tema: general: 

• Ciencias›Ciencias del Medio Ambiente

Timing of early diagenetic sulfurization of organic matter: A precursor-product relationship in Holocene sediments of the anoxic Cariaco Basin, Venezuela

REA Auditado

The incorporation of reduced inorganic sulfur into organic matter is a significant mechanism for the preservation of functionalized organic compounds in the sedimentary environment, but the timing of this process is not currently known.

Tema: general: 

• Ciencias›Ciencias del Medio Ambiente

The influence of mineral matter on the separation of amorphous marine kerogens using density gradient centrifugation

REA Auditado

Three relatively immature amorphous marine kerogens were subjected to density gradient centrifugation (DGC). The density fractions obtained were analyzed by Curie-point pyrolysis in combination with gas chromatography (Py-GC) and with gas chromatography-mass spectrometry (Py-GC-MS). Despite the variations in density, no significant variations were observed in chemical compositions of the flash pyrolysates of the density fractions of each kerogen.

Tema: general: 

• Ciencias›Ciencias del Medio Ambiente

Organic Matter of the Mulhouse Basin, France: A synthesis

REA Auditado

The lower Oligocene evaporite sequence of the Mulhouse Basin (France) contains organic matter-rich marl deposits. These marls display an overall cyclic variation of sedimentation rate, organic carbon content, hydrogen index and selected molecular parameters over a 30 m thick stratigraphic interval. The integration of all sedimentological and geochemical parameters has allowed the reconstruction and characterization of the paleoenvironment of deposition. The marls were deposited in a perennial lake that was at times connected to the sea.

Tema: general: 

• Ciencias›Ciencias del Medio Ambiente

Characterization of high-molecular-weight organic matter in the marls of Salt IV Formation of the Mulhouse basin

REA Auditado

High-molecular-weight organic matter of six marl samples of the Mulhouse Basin has been characterized. The kerogen, asphaltene and polar fractions were analysed by flash pyrolysis-GC-(MS). In addition, sulphur-rich geomacromolecules present in the polar fractions were also desulphurized with Raney Ni and the released hydrocarbons were characterized by GC-MS. The kerogen and asphaltene pyrolysates are dominated by linear and isoprenoid alkanes and alkenes most likely derived from aliphatic biopolymers of algae (algaenans), and contain moderate to low amounts of alkylated thiophenes.

Tema: general: 

• Ciencias›Ciencias del Medio Ambiente

Time inSight : the matter of time in visual perception

REA Auditado

Time: it seems a simple concept, a single dimension along which the world evolves. The future becomes the present, and the present becomes the past, continuously and inexorably. Open your eyes, and you see the world. You think that what you see now is what is happening now. In fact, processing sensory information takes time. By the time the brain has processed the incoming visual information such that you become aware of it, it is outdated. So what you see now, has in truth already happened: when you open your eyes, you see the past.

Tema: general: 

• General