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Four different dicyanamide-based ionic liquids (ILs), [Cnmpy][DCA] (n= 4, 6, 8, and 10), were synthesized, characterized, and used to separate ethylbenzene from n-octane. Equilibrium data for the corresponding ternary systems were measured at 313.15 K under atmospheric pressure. A higher selectivity is observed for lower aromatic concentrations in the feed (20% max); this is a key factor in selecting a suitable IL. The distribution ratio and selectivity obtained in this work are comparable to those of commercial solvents. The nonrandom two-liquid model (NRTL) was successfully used to correlate the experimental tie-lines and to calculate the phase compositions of the ternary systems. Moreover, the antimicrobial activities of the ILs were evaluated by examining their 50% effective concentrations (EC50) using the standard microbroth dilution test against four human bacterial pathogens. 1-Butyl 3-methylpyridinium dicyanamide [C4mpy][DCA] was found as the most suitable IL among those investigated because of its low toxicity with EC50values between 41.35 and 58.08 mmol·L–1and its performance in liquid–liquid extraction for the ethylbenzene/n-octane mixture.

We estimate the upper mantle temperature of the Antarctic Plate based on the thermoelastic properties of mantle minerals and Svelocities using a new 3‐D shear velocity model, AN1‐S. Crustal temperatures and surface heat fluxes are then calculated from the upper mantle temperature assuming steady state thermal conduction. The temperature at the top of the asthenosphere beneath the oceanic region and West Antarctica is higher than the dry mantle solidus, indicating the presence of melt. From the temperature values, we generate depth maps of the lithosphere‐asthenosphere boundary and the Curie temperature isotherm. The maps show that East Antarctica has a thick lithosphere similar to that of other stable cratons, with the thickest lithosphere (~250 km) between Domes A and C. The thin crust and lithosphere beneath West Antarctica are similar to those of modern subduction‐related rift systems in East Asia. A cold region beneath the Antarctic Peninsula is similar in spatial extent to that of a flat‐subducted slab beneath the southern Andes, indicating a possible remnant of the Phoenix Plate, which was subducted prior to 10 Ma. The oceanic lithosphere generally thickens with increasing age, and the age‐thickness correlation depends on the spreading rate of the ridge that formed the lithosphere. Significant flattening of the age‐thickness curves is not observed for the mature oceanic lithosphere of the Antarctic Plate. High‐resolution crust/lithosphere temperature model covering the Antarctic PlateA fossil slab of the Phoenix Plate is found beneath the Antarctic PeninsulaThe age‐thickness relation of oceanic lithosphere depends on ridge spreading rate

Since 2007/2008, seismographs were deployed in many new locations across much of Antarctica. Using the records from 122 broadband seismic stations, over 10,000 Rayleigh wave fundamental‐mode dispersion curves have been retrieved from earthquake waveforms and from ambient noise. Using the processed data set, a 3‐D S‐velocity model for the Antarctic lithosphere was constructed using a single‐step surface wave tomographic method, and a Moho depth map was estimated from the model. Using the derived crustal thicknesses, the average ratio of lithospheric mantle and crustal densities of Antarctica was calculated. The calculated density ratio indicates that the average crustal density for Antarctica is much higher than the average values for continental crust or the average density of lithospheric mantle is so low as to be equal to low‐density bound of Archean lithosphere. The latter implies that the lithospheric mantle in much of Antarctica should be old and of Archean age. The East Antarctic Mountain Ranges (EAMOR) represent a thick crustal belt, with the thickest crust (~60 km) located close to Dome A. Very high velocities can be found at depths greater than 200 km beneath parts of East Antarctica, demonstrating that the continental lithosphere extends deeper than 200 km. The very thick crust beneath the EAMOR may represent the collision suture of East Gondwana with Indo‐Antarctica and West Gondwana during the Pan‐African orogeny. High‐resolution crust/lithosphere Vsmodel covering the whole Antarctic PlateLithospheric mantle in most of the Antarctica is significantly old and buoyantEast Antarctic Mountain Ranges are a thick‐crust belt

Brønsted‐acidic ionic liquids that bear a sulfonic acid group, known as Forbes acids, show a good catalytic activity for the Beckmann rearrangement, used to prepare ε‐caprolactam, which is a precursor of Nylon 6. The activity essentially stems from the acidity of the sulfonic acid group. Although these task specific ionic liquids suffer from a high viscosity, this drawback can be circumvented at higher temperatures. A combination of the hydrogen sulfate anion and the sulfonic acid group of the cation is needed to obtain the rearrangement product rapidly under mild conditions. When using an excess of ionic liquid, we postulate that the internal pressure of the ionic medium, generated by the high viscosity and the high number of hydrogen‐bonds, is strong enough to contribute to a decrease of the thermodynamic barrier. In accordance with the “Principles of Green Chemistry,” we have developed a synthesis of ε‐caprolactam that requires no additional chemicals except cyclohexanone oxime and the reusable TSIL.

AbstractThe blood supply to the skin is provided by a network of arterioles, capillaries and venules organized into a superficial and a deep plexus. The assessment of skin microcirculation is of valuable interest in cosmetology in the quantification of the sun protection factor, skin irritation and efficacy of antiredness treatments. Skin microcirculation can be measured by means of different techniques, based mainly on the quantification of optical and thermal properties of the skin which are modified by the amount of blood perfusion. Relevant and reproducible data can be obtained only through the understanding of the biophysical background of the technique(s) utilized. Standardization of measuring conditions and procedures is particularly required for blood flow assessment. In this paper, the advantages and disadvantages of the main techniques in use are discussed, and optimization of measurements for laser Doppler techniques is described.Copyright © 2002 S. Karger AG, Basel

The use of ionic liquids (ILs) as a novel class of environmentally friendly solvents is now of topical interest among the chemical community, worried about the environmental impact of chemicals. Many reactions of organic chemistry have thus been re-examined since the 1990s. Nevertheless, even if a given preparation of ILs does not represent any particular difficulty, the reaction times appear to be long and the use of large amounts of classical solvents for the synthesis and the purification steps is crucial. This article presents preliminary work performed for the ultrasound assisted preparation of several 1-butyl-3-methylimidazolium salts (BF₄, PF₆, CF₃SO₃ and BPh₄). In all cases a clear yield increase results and a dramatic reduction of the reaction time accompanied by an improved quality of the products occurs. After a short and simple work-up, the ILs are ready to use without a further purification step. Moreover, an original and simple analytical way to follow the reaction in real time is also presented.

AbstractBackground:The stratum corneum (SC) has an important barrier function. The effect of a mechanical stress applied to the SC is controversial on this important physiological parameter. Objective and Methods:To assess both in vitro and in vivo the structure and function of human SC submitted to controlled strains, we measured the transepidermal water loss (TEWL), in vivo, on human skin submitted to controlled strains ranging from 0 to 20% extension imposed by a Densi-score device. We also looked at the structure of the SC by means of X-ray diffraction and transmission electron microscopy. Results:Transmission electron microscopy and X-ray diffraction analysis were performed on harvested and stretched human SC. TEWL was not significantly influenced by the relative deformation applied to the skin. At high strain (60%) imposed in vitro to the SC, lipid bilayers and corneosomes were detached from corneocytes. Only rare corneosomes showed internal disruption. X-ray analysis did not reveal modifications in the supramolecular organization of intercellular lipids while stretching the SC. Conclusion:Submitting human SC to an extension force up to 20% elongation does not significantly alter the barrier function. Copyright © 2002 S. Karger AG, Basel

The role of the structural organization of intercorneocyte lipids in the barrier function of human stratum corneum was evaluated by treatment with heat and sodium lauryl sulfate. Measurement of transepidermal water loss in treated samples was used to quantify variations in stratum corneum permeability. Thermodynamic transition of lamellar lipids and their degree of organization were evaluated by differential scanning calorimetry and small-angle X-ray diffraction, respectively. Progressively preheating stratum corneum samples from 75°C to 90°C increased stratum corneum permeability to water vapor, while the fusion temperature of lamellar lipids and the intensity of the X-ray diffraction peaks of the polar lipids decreased. Sodium lauryl sulfate induced similar variations of these three parameters. These results support the hypothesis that, in addition to the chemical nature of intercorneocyte lipids, their structural arrangement and thermodynamic properties play an important role in the barrier function of the stratum corneum to water vapor.

The article profiles painter H. H. Steffens. He spent his childhood in Berlin, Germany at the time when the Nazi danger was growing, then he was imprisoned during the Russian Front and became a professor after his release. He then decided to live in the Roussillon region of France where he created imprints on stones and walls based on signs, writings and scratches. Several photographs of his works are also offered.

A biography of Gildo Caputo, an art dealer and gallery director, is presented. He was born of Italian parents in Paris, France on June 24, 1904. His inclination in art can be traced in his childhood where he has been exposed to literature and music. He is the grandson of the famous Italian editor Andelo Sommaruga. He studied in Louis le Grand school and became a friend of Vicente Huidobro, a Chilian poet. His way to achieve his accomplishments as art director and dealer is explored.

The article examines the totems and artworks made by sculptor Moon Shin. The monumental sculpture conceived by Shin in the context of Seoul Olympic Games is taken into account. The sculpture's association with the Tower of Babel and Romanian sculptor Constantin Brancusi's dizzying climbing columns is discussed. The sexual symbolism in many of his finely-worked pieces is also explored.

The article discusses the paintings of realist painter Istvan Sandorfi. His works were based on taken photographs. The details of such photographs become the material and the subject of his paintings which may undergo framing and demobilizing. His works are said to have the same pictorial meticulousness and usually express violence and suffering. Several art works of Sandorfi are also presented.

The article provides the author's view on the works Slavko Kopac, a Croatian painter. Commonly known for his last name, Kopac's portraits of women depicts a collection of debris with a feeling of delight and not according to a principle of lesson-giver of morals. According to the author, each painting of Kopac is the story of his adventure as much as the finality of a representation. Several paintings of Kopac are also presented.

The article features the works of painter Barros. Barros was born in Lisbon, Portugal in 1929 and went to Hamburg, Germany to study with a former student of Klee. His painting is defined as an exercise in a feeling of extreme pleasure which avoids the ruling theories and schools. His works maintain tonality through shades and have rhythms that make it alive and real.

The article profiles Léon Gischia who was a nonfigurative painter of the News École of Paris, France. It notes the quality of Gischia's works, particularly noting how his works present harmony and unity by its chromatic musicality and by its purely decorative element. Several photographs of his works are also presented.

The article focuses on the art work of Achille Perilli, an Italian painter whose works flourished in the 20th century which was characterized by a rich expression in geometry. The liberation of his instincts coupled with the domination of his intelligence paved the way for the distinctive style manifested in his works. Perilli's style modified in the passage of time, from the curved, droll, and grotesque silhouettes which recall Flemish sarabands to a more refined fashion. INSET: Biographie.

Multiparameter inversions of multimode dispersion data are performed for two large regions: the Pacific Ocean and North America. Anisotropy is taken into account by considering transversely isotropic structures with a vertical axis of symmetry. Two fundamental questions are studied in detail: (1) how to make the inverted models consistent when using different sets of parameters, (2) what is the significance of transversely isotropic inversion for the actual Earth's structure? It is proved that full consistency of the inverted models can be achieved by properly taking into account some a priori informations on the model and it is shown that the use of transversely isotropic models with vertical axis of symmetry does not cause severe limitations when interpreting the data. The models we have obtained are discussed in the light of these investigations. Considering an olivine-rich upper mantle, we make a tentative interpretation of these models in terms of preferred orientation of the a-axis of the crystals in one fixed horizontal direction.