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A portable X-ray powder diffractometer (p-XRD) PT-APXRD III has been developed for on-site analysis of paintings and archaeological samples. By using a Cu anode X-ray tube and a silicon drift diode (SDD) detector, diffraction patterns with a high signal-noise (S/N) ratio can be recorded. The X-ray tube can be operated at a maximum voltage of 60 kV, which makes it possible to simultaneously record X-ray fluorescence spectra up to the high-energy region. The total weight of this instrument is 16 kg, which can be carried anywhere and the goniometer unit (5.6 kg) can be placed on a tripod for analysis of mural paintings. We brought the instrument to the Rijksmuseum in the Netherlands to examine its applicability for the analysis of oil paintings. We successfully analyzed two seventeenth-century oil paintings by Johannes Vermeer and Jan Davidsz de Heem (copy after). Ultramarine blue, lead-tin yellow type I, and Naples yellow were identified from the diffraction patterns, demonstrating the high practicality of this instrument. Furthermore, it was found from the SEM-EDX analysis of a paint cross section that the yellow pigment was applied in separate layers rather than being mixed. This diffractometer will be commercially available in the near future and will have many applications in the field of material analysis. [ABSTRACT FROM AUTHOR]

Chemical state of cadmium in a hepatopancreas of a scallop (Patinopecten yessoensis) was studied by means of synchrotron radiation‐based X‐ray analytical techniques. X‐ray absorption fine structure (XAFS) and X‐ray fluorescence (XRF) imaging were used to identify the chemical state and the distribution of cadmium in the hepatopancreas, respectively. The results of invivo Cd K‐edge XAFS suggested that the neighboring atoms of the cadmium in the hepatopancreas are of sulfur. Therefore, we propose that cadmium was accumulated by a metalloprotein with sulfur. Micro XRF imaging of thin sections of the hepatopancreas showed that cadmium is distributed on the surface of intestinal epithelia and concentrated in the internal tissue of the hepatopancreas. These results indicated that scallops accumulate cadmium inside the hepatopancreas through the intestinal epithelium. [ABSTRACT FROM AUTHOR]

A prototype transition-edge sensor (TES) microcalorimeter is successfully integrated into a commercial field-emission scanning electron microscope (FE-SEM). The microcalorimeter is composed of a gold (Au) absorber, a Au/Ti bilayer thermometer and a thermal isolation structure with a SiNx membrane. Operating temperatures of 100–150 mK are obtained with a dilution refrigerator. The measured energy resolution was between 19–22 eV for Al Kα at an acceleration voltage of 5 keV. The newly developed system was applied to the analysis of nanosheets for the first time at a low acceleration voltage (≤ 5 kV). The energy dispersive spectrometer (EDS) spectra of Nb3O8 nanosheets of different thicknesses (less than 20 nm) were successfully detected. Moreover, Au particles on carbon nanotubes with a thickness less than 1 nm are detected clearly. With further improvement of both energy resolution and count rate, this system holds the promise for practical X-ray compositional characterization of nanomaterials with high image spatial resolution in the low-acceleration-voltage regime. [ABSTRACT FROM AUTHOR]

Highlights: [•] We developed a rapid and simple technique for the provenance analysis of soybean. [•] Our XRF technique allows the determination of trace elements at sub-μgg−1 levels. [•] Concentrations of Mg, P, Cl, K, Mn, Cu, Br and Ba were used for statistical analyses. [•] The trace element signatures distinguished between domestic and imported soybean. [•] The XRF technique was also suitable for the rapid analysis of Br content in food. [ABSTRACT FROM AUTHOR]

Abstract: An indole alkaloid (hypaphorine (1)) was isolated from Brazilian medicinal plant, Erythrina velutina (Leguminosae). This compound was investigated for sleep promoting effects in mice, and the results showed that it significantly increased non-rapid eye movement (NREM) sleep time during the first hour after its administration. The NREM sleep time was enhanced by 33% in the experimental mice when compared to that of the controls. This study therefore confirmed its sleep promoting property. [Copyright &y& Elsevier]

Co doped rutile thin films were fabricated onα-Al 2 O 3 (10-12) substrates by laser molecular beam epitaxy. X-ray diffraction, scanning electron microscopy, and transmission electron microscopy indicated that the rutile thin films are (101) oriented and have smooth surfaces with no impurity phases. Co K-edge x-ray absorption near-edge structure, extended x-ray absorption fine structure, and x-ray photoelectron spectroscopy revealed the coexistence of different valence states of Co in the film. Magnetic circular dichroism studies suggest that the observed ferromagnetism is uniform and is related to the electron band structure of TiO 2 rutile. Contribution of oxidized (Co 2+) and metallic (Co 0) cobalt to the ferromagnetism is discussed. [ABSTRACT FROM AUTHOR]

This paper reports on how the application of macro X-ray fluorescence (MA-XRF) imaging, in combination with the re-examination of existing paint cross-sections, has led to the discovery of a new pigment in Rembrandt's palette: artificial orpiment. In the NWO Science4Arts 'ReVisRembrandt' project, novel chemical imaging techniques are being developed and applied to the study of Rembrandt's late paintings in order to help resolve outstanding questions and to gain a better understanding of his late enigmatic painting technique. One of the selected case studies is the Portrait of a Couple as Isaac and Rebecca, known as 'The Jewish Bride', dated c. 1665 and on view in the Rijksmuseum. During the re-installation of the Rijksmuseum in 2013, the picture was scanned using the Bruker M6 Jetstream MA-XRF scanner. The resulting elemental distribution maps made it possible to distinguish many features in the painting, such as bone black remains of the original hat (P, Ca maps), and the now discolored smalt-rich background (Co, Ni, As, K maps). The arsenic (As) map also revealed areas of high-intensity in Isaac's sleeve and Rebecca's dress where it could be established that it was not related with the pigment smalt that also contains arsenic. This pointed to the presence of a yellow or orange arsenic-containing pigment, such as realgar or orpiment that is not associated with the artist's palette. Subsequent examination of existing paint cross-sections from these locations taken by Karin Groen in the 1990s identified isolated, almost perfectly round particles of arsenic sulfide. The round shape corresponds with published findings on a purified form of artificial orpiment glass obtained by dry processing, a sublimation reaction. In bright field, the particles characteristically exhibit a dark cross in the middle caused by internal light reflections. The results of additional non-invasive techniques (portable XRD and portable Raman) are discussed, as well as the implications of this finding and how it fits with Rembrandt's late experimental painting technique. [ABSTRACT FROM AUTHOR]

Abstract: Gynura pseudochina (L.) DC. is a zinc (Zn)/cadmium (Cd) hyperaccumulative plant. The aim of this study was to examine the tolerance of G. pseudochina (L.) DC. for Zn and/or Cd accumulation and protein expression. An in vitro tissue culture system was used to control the environment and effects of the microorganisms. Treatments with higher Zn and Cd concentrations increased chlorosis and the accumulation of metals in the root and shoot. Cd treatment at low levels induced the growth of the plant, and the translocation factor was high. A dual treatment with Cd and Zn decreased the metals’ toxicity and demonstrated the plant’s proclivity to accumulate Cd. The SDS–PAGE and FT-IR analyses showed the effect of the metals’ toxicity on protein expression and secondary structure. Moreover, using XAFS techniques, it was demonstrated that treatment with a high Zn concentration (100mgl−1) resulted in tetrahedral coordination with mixed S/O ligation in the protein extract as compared with Znation in the protein extract from the control plant cultured in the presence of trace levels of Zn (0.04mgl−1). This research suggested that G. pseudochina (L.) DC. had properties to tolerate a high Zn and Cd concentration, related to the sulphur proteins. [Copyright &y& Elsevier]