Determination of Anthracene Derivatives in Baltic Amber Using SERS.

The article describes the results of Raman spectroscopy and SERS for the study of fluorescent components of Baltic amber via the extraction method. Using SERS, it was possible to confirm the presence of anthracene derivatives in amber: tetracene and benzanthracene. It has been shown that SERS methods are effective for the detection of aromatic compounds; they increase the registered Raman signal and make it possible to identify peaks characteristic of the compounds under study.

Spectral homogeneity of human platelets investigated by SERS.

This paper describes a detailed study of the spectral homogeneity of human platelets using Surface-enhanced Raman spectroscopy (SERS). We used a combined approach based on multivariate methods as principal component analysis and pair correlation algorithms to investigate platelets spectral properties. The correlation coefficients for each sample have been calculated, and the average coefficient of determination has been estimated.

Diamond refractive micro-lenses for full-field X-ray imaging and microscopy produced with ion beam lithography.

We demonstrate that ion-beam lithography can be applied to the fabrication of rotationally parabolic refractive diamond X-ray micro-lenses that are of interest to the field of high-resolution X-ray focusing and microscopy. Three single half-lenses with curvature radii of 4.8 µm were produced and stacked to form a compound refractive lens, which provided diffraction-limited focusing of X-ray radiation at the P14 beamline of PETRA-III (DESY).

Impact of beryllium microstructure on the imaging and optical properties of X-ray refractive lenses.

Beryllium is one of the most transparent materials to hard X-ray radiation and, as a direct consequence, it is the main material for the fabrication of X-ray refractive optics and instrumentation for synchrotron radiation sources and free-electron laser facilities. However, it is known that almost all beryllium currently in use is polycrystalline material. In this paper, the influence of the microstructure of different beryllium grades on the optical properties of X-ray refractive lenses is studied.

CRL-based ultra-compact transfocator for X-ray focusing and microscopy.

A new ultra-compact transfocator (UCTF) based on X-ray compound refractive lenses (CRLs) is presented. The device can be used to change the number of one- and two-dimensional focusing CRLs by moving the individual parabolic lenses one-by-one independently, thus providing permanent energy and focal-length tunability for scanning and full-field X-ray microscopy applications. The small overall size and light weight of the device allow it to be integrated in any synchrotron beamline, while even simplifying the experimental layout.

Zernike phase contrast in high-energy x-ray transmission microscopy based on refractive optics.

The current work represents the first implementation of Zernike phase contrast for compound refractive lens based x-ray microscopy, and also the first successful Zernike phase contrast experiment at photon energies above 12 keV. Phase contrast was achieved by fitting a compound refractive lens with a circular phase plate. The resolution is demonstrated to be sub-micron, and can be improved using already existing technology.

Protective radiolucent aluminium oxide coatings for beryllium X-ray optics.

Beryllium, being one of the most transparent materials to X-ray radiation, has become the material of choice for X-ray optics instrumentation at synchrotron radiation sources and free-electron laser facilities. However, there are concerns due to its high toxicity and, consequently, there is a need for special safety regulations. The authors propose to apply protective coatings in order to seal off beryllium from the ambient atmosphere, thus preventing degradation processes providing additional protection for users and prolonging the service time of the optical elements.

Highly porous nanoberyllium for X-ray beam speckle suppression.

This paper reports a special device called a `speckle suppressor', which contains a highly porous nanoberyllium plate squeezed between two beryllium windows. The insertion of the speckle suppressor in an X-ray beam allows manipulation of the spatial coherence length, thus changing the effective source size and removing the undesirable speckle structure in X-ray imaging experiments almost without beam attenuation. The absorption of the nanoberyllium plate is below 1% for 1 mm thickness at 12 keV.