A hitherto unknown composition is highlighted in the red and black inks preserved on ancient Egyptian papyri from the Roman period (circa 100 to 200 CE). Synchrotron-based macro–X-ray fluorescence (XRF) mapping brings to light the presence of iron (Fe) and lead (Pb) compounds in the majority of the red inks inscribed on 12 papyrus fragments from the Tebtunis temple library. The iron-based compounds in the inks can be assigned to ocher, notably due to the colocalization of Fe with aluminum, and the detection of hematite (Fe₂O₃) by micro–X-ray diffraction. Using the same techniques together with micro-Fourier transform infrared spectroscopy, Pb is shown to be associated with fatty acid phosphate, sulfate, chloride, and carboxylate ions. Moreover, micro-XRF maps reveal a peculiar distribution and colocalization of Pb, phosphorus (P), and sulfur (S), which are present at the micrometric scale resembling diffused “coffee rings” surrounding the ocher particles imbedded in the red letters, and at the submicrometric scale concentrated in the papyrus cell walls. A similar Pb, P, and S composition was found in three black inks, suggesting that the same lead components were employed in the manufacture of carbon-based inks. Bearing in mind that pigments such as red lead (Pb₃O₄) and lead white (hydrocerussite [Pb₃(CO₃)₂(OH)₂] and/or cerussite [PbCO₃]) were not detected, the results presented here suggest that the lead compound in the ink was used as a drier rather than as a pigment. Accordingly, the study calls for a reassessment of the composition of lead-based components in ancient Mediterranean pigments. Significance Ink, invented in ancient Egypt circa 5,000 y ago, is the established and time-honored medium wherewith humankind commits words to writing. A comprehensive synchrotron-based microanalysis of a considerable corpus of ancient Egyptian papyri from the Roman period, inscribed with red and black inks, reveal a hitherto undetected complex composition of inks. Highlighted by the presence of iron, the red color can be attributed to the use of ocher. Unexpectedly, lead is regularly present in both the red and black inks and is associated to phosphate, sulfate, chloride, and carboxylate ions. The analysis shows that lead was probably used as a drier rather than as a pigment, similar to its usage in 15th century Europe during the development of oil paintings.

The performance of a new X-ray spectrometer is presented. The device was designed originally to be employed in environmental sciences, and allows the use of different types of primary radiation sources, such as a radioactive source (²⁴¹Am) or tubes with anodes of different metals (Rh or W). Among the advantages of this spectrometer are the possibility of exchanging detectors to improve efficiency at different X-ray energy ranges [such as Si (Li), Si-PIN, hyperpure Ge, or CdTe detectors], to attach it to a wavelength dispersive system, and its use in vacuum or atmospheric pressure. Furthermore, it is feasible to modify the geometry so a secondary target may be installed for using polarized X-rays as exciting radiation.

The morphology of TiO₂ particles and their status within soil aggregates may provide insights on their origin.

An extended study on an advanced method for the cleaning of carbon contaminations from large optical\ud surfaces using a remote inductively coupled low-pressure RF plasma source (GV10x DownStream Asher)\ud is reported. Technical and scientific features of this scaled up cleaning process are analysed, such as the\ud cleaning efficiency for different carbon allotropes (amorphous and diamond-like carbon) as a function of\ud feedstock gas, RF power (from 30 to 300W), and source-object distances (415 to 840 mm). The underlying\ud physical phenomena for these functional dependences are discussed.The authors would like to acknowledge the help by Guillaume\ud Sauthier (ICN2) for his collaboration during the XPS characterization.\ud We also thank ibss Group Inc. for supplying the GV10x DS\ud Asher systems as well as the DLC samples.Peer reviewe

The increasing number of patents suggests that the use of nanoparticles (NPs) in agriculture will continue to grow in the future. Properties associated with nanosized objects might be desirable, but may pose a threat to the environment since the fate of nanomaterials is poorly understood. Seed treatment is an extensive practice to provide micronutrients and disease protection. This study investigates the effect of Ag₂S NPs, Ag⁰ NPs, and AgNO₃ (1, 100, and 1000 mg Ag per L) on the germination of Phaseolus vulgaris seeds and the mechanism of interaction in the seed coat. Ag treatments did not affect the germination rate. On the other hand, the development of seedlings was significantly improved by Ag₂S NPs while AgNO₃ showed a negative effect compared to the control (water). Silver from different sources was accumulated and biotransformed along the seed coat. Ag from the AgNO₃ treatment was found as AgCl and bound to oxygen, and Ag⁰ NPs underwent oxidative dissolution forming thiolate complexes. On the other hand, Ag₂S NPs did not show any detectable chemical changes. Silver distribution and speciation were investigated in the bean testa using μ-XRF and μ-XANES, while the macromolecular composition was assessed by ATR-FTIR. The Ag biotransformation depended on the source. For the FTIR results, it is possible to verify perturbations in the carbohydrate region as well as changes in the protein region. The combination of these results can contribute to building another step in the understanding of how nanoparticles can improve agricultural inputs and benefit food crops.