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Moon4You is a project led by the Dutch Organisation for Applied Scientific Research TNO, with partners from industry and universities in the Netherlands that aims to provide a combined Raman/LIBS instrument as scientific payload for lunar exploration missions. It is the first time that Raman spectroscopy and LIBS (Laser Induced Breakdown Spectroscopy) are combined into one miniaturised instrument with minimum mass, volume and use of resources and can deliver data-products almost instantly. These characteristics make it the next-generation instrument for mineralogical and elemental (atomic) characterisation of lunar soil and rock samples, as well as for a host of other planetary exploration and terrestrial applications. © 2009 SPIE.

We report thin-film morphology studies of inkjet-printed single-droplet organic thin-film transistors (OTFTs) using angle-dependent polarized Raman spectroscopy. We show this to be an effective technique to determine the degree of molecular order as well as to spatially resolve the orientation of the conjugated backbones of the 6,13-bis(triisopropylsilylethynyl)pentacene (TIPS-Pentacene) molecules. The addition of an insulating polymer, polystyrene (PS), does not disrupt the p-p stacking of the TIPS-Pentacene molecules. Blending in fact improves the uniformity of the molecular morphology and the active layer coverage within the device and reduces the variation in molecular orientation between polycrystalline domains. For OTFT performance, blending enhances the saturation mobility from 0.22 ± 0.05 cm2/ (V·s) (TIPS-Pentacene) to 0.72 ± 0.17 cm2/(V·s) (TIPS-Pentacene:PS) in addition to improving the quality of the interface between TIPS-Pentacene and the gate dielectric in the channel, resulting in threshold voltages of ~0 V and steep subthreshold slopes. © 2011 American Chemical Society.

We show the chemical identification and quantification of the concentration and size of nanoparticle (NP) dispersions in aqueous solutions by using a combination of Raman Spectroscopy and Laser Induced Breakdown Spectroscopy (LIBS). The two spectroscopic techniques are applied to demonstrate the NP detection for off-line configuration. The implementation of the techniques for further in-line and on-line NP monitoring will allow for the optimization of the synthesis process, reduction of the failure rate and improvement of NP quality. We demonstrate the implementation of the Raman-LIBS technique on two metaloxide nanoparticles: titanium dioxide (TiO2) and a rare earth sesquioxide nanoparticle, holmium oxide (Ho2O3). The determination of the elemental (LIBS) and molecular (Raman) compositions, as well as the determination of the particle size down to 5 nm is demonstrated. The LIBS spectra of NP dispersions reveal the absorption of the continuum emission by the electrons present in the plasma via the inverse Bremsstrahlung effect. This effect manifests as the appearance of dips in the LIBS spectrum, rather than the conventional emission peaks. An interpretation of these spectra that incorporates this absorption effect is presented, enabling new opportunities for understanding the LIBS spectra of liquids. © 2013 Elsevier B.V. All rights reserved.

The chemical composition of vascular lesions, an important determinant of plaque progression and rupture, can not presently be determined in vivo. Prior studies have shown that Raman spectroscopy can accurately quantify the amounts of major lipid classes and calcium salts in homogenized coronary artery tissue. This study determines how the relative cholesterol content, which is calculated from Raman spectra collected at the luminal surface of an artery, is related to its depth in an intact arterial wall. Raman spectra of human atherosclerotic plaques were measured after thin tissue layers were successively placed on them. From these spectra, relative cholesterol contents were calculated and used to determine how cholesterol signal strength is attenuated by overlaying tissue. Then, intact artery samples (n = 13) were examined spectroscopically, sectioned and stained specifically for cholesterol. Images of these sections were digitized, and image intensities were related to cholesterol content. These cholesterol amounts were weighed appropriately for depth into the tissue and area-integrated for comparison with spectroscopy results. A decaying exponential curve was fit to the layer study data (r2 = 0.97) and showed that ~ 300 μm of tissue attenuates cholesterol signals by 50%. In intact plaques, the spectroscopically- determined cholesterol amounts correlated strongly and linearly with those determined by digital microscopy (r2 = 0.94). With Raman spectroscopy techniques, the cholesterol content of a lesion can be determined by properly accounting for its depth into an arterial wall. Our results suggest that chemical concentrations in an artery wall could be mapped throughout its thickness, possibly by combining Raman spectroscopy methods with other techniques.

The kinetics of formation of H2-TBAB semi-clathrate hydrates was studied in this work in order to elucidate their potential for H2 storage. The influence of pressure (5-16 MPa), TBAB concentration (2.6 mol% and 3.7 mol%) and formation method (T-cycle method and T-constant method) on the hydrate nucleation, hydrate growth and H2 storage capacity was determined. The results showed that kinetics is favored at higher pressures and solute concentrations. Additionally, the hydrate phase formation and dissociation was study for a solution of 2.6 mol% of TBAB in situ by using the Raman spectroscopy technique. The inclusion of H2 in the semi-hydrate phase was confirmed. The results showed the importance of H2 mass transfer on the storage capacity of the H2-TBAB semi-hydrates. © 2011, Hydrogen Energy Publications, LLC. Published by Elsevier Ltd. All rights.

Laser-assisted chemical vapour deposition (CVD) growth is an attractive mask-less process for growing locally aligned carbon nanotubes (CNTs) in selected places on temperature sensitive substrates. The nature of the localized process results in fast carbon nanotube growth with high experimental throughput. Here, we report on the detailed investigation of growth kinetics related to physical and chemical process characteristics. Specifically, the growth kinetics is investigated by monitoring the dynamical changes in reflected laser beam intensity during growth. Benefiting from the fast growth and high experimental throughput, we investigate a wide range of experimental conditions and propose several growth regimes. Rate-limiting steps are determined using rate equations linked to the proposed growth regimes, which are further characterized by Raman spectroscopy and Scanning Electron Microscopy (SEM), therefore directly linking growth regimes to the structural quality of the CNTs. Activation energies for the different regimes are found to be in the range of 0.3-0.8 eV. © 2014 the Owner Societies.

The kinetics of formation of semi-clathrate hydrates of tetra n-butyl ammonium fluoride (TBAF) with hydrogen (H2) and carbon dioxide (CO2) were studied in order to elucidate their potential for H 2 storage as well as for CO2 sequestration. The influence of pressure, TBAF concentration (1.8 mol% and 3.4 mol%) and formation method (T-cycle method and T-constant method) on the hydrate nucleation, hydrate growth and the amount of gas uptake were determined. The results showed that the kinetics of formation of H2-TBAF semi-hydrates is favored at high pressures and TBAF concentrations. The TBAF concentration did not display a large influence on the kinetics of formation of CO2-TBAF semi-hydrates and pressure only showed a major influence on the formation rate. Instead, the induction time and the amount of CO2 consumed were favored at low temperatures. Additionally, in situ Raman spectroscopy was used to confirm the gas uptake in the hydrate structure and to observe structural changes. © 2013, Hydrogen Energy Publications, LLC. Published by Elsevier Ltd. All rights.

Moon4You is an initiative led by the Dutch Organisation for Applied Scientific Research TNO, with partners from industry and universities in the Netherlands that aims to provide a combined Raman/LIBS instrument as scientific payload for lunar exploration missions, and specifically for Odyssey Moon's MoonOne mission, slated for launch in the second half of 2012. It is the first time that Raman spectroscopy and LIBS (Laser Induced Breakdown Spectroscopy) are combined into a single miniaturised instrument with minimum mass, volume and use of resources and can deliver data-products almost instantly. These characteristics make it the next-generation instrument for mineralogical and elemental (atomic) characterisation of lunar soil and rock samples, as well as for a host of other planetary exploration and terrestrial applications. This instrument would be the first Dutch 'footprint' on the surface of the Moon. We believe we will obtain the necessary investments for the Moon4You programme from the private sector by advocating the projected high media visibility of the Google Lunar X PRIZE, the potential of the combined Raman/LIBS technology for a large range of Space and on-Earth applications and the inspiration that the Moon4You programme will deliver for science education in the Netherlands. Copyright © 2009 International Astronautical Federation.

Two step atmospheric pressure processing of Cu(In,Ga)(Se,S)2 absorbers is an industrially attractive technology to produce CIGS thin film modules. For this procedure, absorber sulfurization is required to increase the Voc and thus the efficiency of the solar cells. Raman spectroscopy was used to qualitatively identify the presence of sulfur on the surface of the absorber. Moreover WDXRF and GDOES were used to quantitavely determine the sulfur content in the top of the absorbers. These results were used to globally quantify the Raman results. © 2018 IEEE.

Retinal diseases, such as age-related macular degeneration, are leading causes of vision impairment, increasing in incidence worldwide due to an aging society. If diagnosed early, most cases could be prevented. In contrast to standard ophthalmic diagnostic tools, Raman spectroscopy can provide a comprehensive overview of the biochemical composition of the retina in a label-free manner. A proof of concept study of the applicability of nonresonant Raman spectroscopy for retinal investigations is presented. Raman imaging provides valuable insights into the molecular composition of an isolated ex vivo human retina sample by probing the entire molecular fingerprint, i.e., the lipid, protein, carotenoid, and nucleic acid content. The results are compared to morphological information obtained by optical coherence tomography of the sample. The challenges of in vivo Raman studies due to laser safety limitations and predefined optical parameters given by the eye itself are explored. An in-house built setup simulating the optical pathway in the human eye was developed and used to demonstrate that even under laser safety regulations and the above-mentioned optical restrictions, Raman spectra of isolated ex vivo human retinas can be recorded. The results strongly support that in vivo studies using nonresonant Raman spectroscopy are feasible and that these studies provide comprehensive molecular information of the human retina. © The Authors. Published by SPIE.

Self-monitoring of glucose is important for managing diabetes. Noninvasive glucose monitors are not yet available, but patients would benefit highly from such a device. We present results that may lead to a novel, point-of-care noninvasive system to measure blood glucose based on Raman spectroscopy. A hospitalized cohort of 111 subjects was measured using a custommade Raman spectrometer system. Blood glucose reference samples were used to correlate Raman data to glucose levels, using advanced preprocessing and analysis algorithms. A correlation coefficient (R2) of .83 was found correlating independent Raman-based predictions on reference blood glucose for the full cohort. Stratification of the cohort in gender-specific groups raised correlation levels to .88 (females) and .94 (males). Glucose could be measured noninvasively with average errors as low as 0.9 mM. We conclude that this novel system shows promising results for the advance of noninvasive, point-of-care glucose monitoring.