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Thermal maturity of six organic rich samples from Jurassic continental successions cropping out in the Holy Cross Mountains in Central Poland, has been characterized by classic thermal maturity indicators, micro-Raman spectroscopy and Palynomorph Darkness Index, in order to create a multi-method workflow for complex palynofacies thermal maturity assessment. Transmitted light observations on dispersed organic matter define a Hettangian lacustrine depositional environment, characterized by periods of reducing/oxidizing conditions and variable sedimentation rates. Thermal maturity detected by classical maturity indicators and PDI indicates an early maturation stage of hydrocarbon generation and is in agreement with spectroscopic analyses performed on phytoclast groups. Moreover, Raman parameters in the sporomorph group indicate a systematic shift toward a lower degree of aromatization compared to the phytoclast group. Finally, the multivariate statistical analysis performed on Raman spectra is found to be a promising tool to define and predict the heterogeneity of dispersed organic matter in sediments.

Poland is considered the most prospective country for shale gas production in Europe. Hydrocarbon generation/expulsion scenarios, drawn in the latest intensive exploration phases, tend to overestimate maturation levels when compared with brand new data acquired after recent drillings. We tested an integrated workflow to correlate published and original thermal maturity datasets for the Paleozoic to Jurassic successions cropping out in the Holy Cross Mountains. These successions, when preserved in subsurface, host the major source rocks in the area. The application of the workflow allowed us to highlight the burial and thermal evolutionary scenarios of the two tectono-stratigraphic blocks of the Holy Cross Mountains (Łysogory and Kielce blocks) and to propose this approach as a tool for reducing levels of uncertainty in thermal maturity assessment of Paleozoic successions worldwide. In particular, published datasets including colour alteration indexes of Paleozoic microfossils (conodont, acritarchs) and vitrinite and graptolite reflectance data, show differences in levels of thermal maturity for the Łysogory (mid mature to overmature) and Kielce (immature to late mature) blocks. Original data, derived from optical analysis, pyrolysis, and Raman spectroscopy on kerogen, and X-Ray diffraction on fine-grained sediments, mostly confirm and integrate published data distribution. 1D thermal models, constrained by these data, show burial and exhumation events of different magnitude, during the Late Cretaceous, for the Łysogory (maximum burial depths of 9 km) and Kielce (burial depths of 6 km) blocks that have been related to the Holy Cross Fault polyphase activity. In the end, Palynomorph Darkness Index and Raman spectroscopy on kerogen, for Llandoverian and Cambrian rocks, turned out to be promising tools for assessing thermal maturity of Paleozoic organic facies devoid of vitrinite macerals.

We have studied the controlled adsorption of molecules of volatile compounds on thin Langmuir-Blodgett films of porphyrins deposited onto the surface of a quartz microbalance. The modification of the film optical anisotropy has been measured by reflectance anisotropy spectroscopy (RAS), and simultaneously, the amount of adsorbed molecules has been monitored. Optical spectra measured after adsorption of single analytes are interpreted straightforwardly in terms of anisotropies related to the H-like and J-like aggregation modes of porphyrins. By an appropriate selection of analytes, we have then investigated the effect of the exposure to controlled vapor mixtures. The experimental RAS line shape variation with respect to the signal measured before exposure is the sum of the variations produced by single analytes. This shows that the identification of types and even quantities of gases and vapors in gas sensing experiments is possible, and the responses of the sensing layer to single analytes could be listed in a library. © 2011 American Chemical Society.

A stable pseudomorphic phase of alpha-quaterthiophene, a well known organic semiconductor, is obtained by growing films with organic molecular beam epitaxy (OMBE) on a single crystal of another organic semiconductor, namely, tetracene. The structural characteristics of the new phase are investigated by monitoring in situ the OMBE process by reflectance anisotropy spectroscopy; thus assessing that incommensurate epitaxy is in this case, the driving force for tuning the molecular packing in organic molecular films and in turn, their solid state properties. ©2009 American Institute of Physics

Reflectance anisotropy spectra of porphyrin thin films (30 monolayers) show a permanent change in their line shape when porphyrins are exposed to some specific analytes (e.g., amines). From this experimental evidence, we concluded that a molecular package adjustment occurred in the film upon interaction with the volatile compound, most likely in the outermost layers. This result is of paramount importance for the consequent application of these films in optical gas-sensors. Consequently, this system could be used as a prototype for optical gas-sensing of aggressive analytes or, more ambitiously, to investigate the porphyrinanalyte interaction. © 2009 Society of Photo-Optical Instrumentation Engineers.

The controlled adsorption of molecules of volatile compounds on Langmuir-Schäfer films of tetraphenylporphyrins produces a modification of the film optical anisotropy, as revealed by reflectance anisotropy spectroscopy (RAS). These experiments allow a better understanding of the molecular package occurring in the film as well as of its alteration upon the interaction with volatile compounds, helping in the comprehension of the mechanisms responsible for the binding of molecules. The results recommend RAS as a potential transducer technique for chemical sensing. © 2009 American Institute of Physics.