We describe the development of a miniaturized HPGe gamma-spectrometer for space applications. The spectrometer is designed around a 170 cm3 intrinsically pure n-type Ge crystal in the closed-end coaxial configuration cooled by a miniature Sterling cycle electric cooler. The complete assembly has a mass of 2.9 kg and consumes 6.6 W under normal operation. The spectrometer was tested in a specially designed chamber which simulates the space environment. FWHM energy resolutions of 2.9 keV and 4.0 keV were achieved at 122 keV and 1332 keV, respectively. With the cooler switched-off, these improved to 2.0 keV and 3.0 keV, respectively, indicating that induced noise from the mechanical vibrations of the cooler accounts for about half the resolution.

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Supramolecular organic systems can be used as a host for the encapsulation of small organic molecules. Here, we chose melamine barbiturate as a robust system capable of supramolecular assembly and the Rhodamine 6G dye entrapment as a guest molecule. The encapsulation of the dye was investigated by UV-visible spectroscopy, SEM and optical fluorescent microscopy while the insight into the crystal structure of the system was obtained by single crystal and powder XRD. For investigation of the system’s properties on a molecular level, the DFT and Classical Molecular Dynamics methods were utilized. Surprisingly, both theoretical and experimental data show not only the successful encapsulation of Rhodamine 6G molecules inside the supramolecular assembly, but also that inclusion of such molecules leads to the drastic improvement in the organic crystal shape. The melamine barbiturate in presence of the Rhodamine 6G molecules tend to form crystals with lesser degree of twinning and higher symmetry in shape than the ones without dye molecules.

This article presents a methodology for the selection of priorities for science and technology (S&T) cooperation among the BRICS countries of Brazil, Russia, India, China and South Africa based on an analysis of international and national strategic documents of BRICS countries and a bibliometric analysis of joint publications by researchers from BRICS countries indexed in the Scopus database. The national S&T priorities for countries are systemized and a comparative assessment of capacities for S&T development in BRICS countries is developed. Indicators of publication activity of all BRICS countries have significantly increased since 2000. Analysis shows that Russia must pay particular attention to the development of cooperation with China, which is already one of the leaders on the global S&T stage. Cooperation with India, Brazil and, in some research areas, with South Africa could also have a positive impact on the performance of research and development in Russia. A list of 14 thematic priorities for S&T cooperation for BRICS countries is presented in the paper based on the analysis of a set of national, bilateral and multilateral strategic and forward-looking documents. Priorities of S&T development create a basis for more efficient and mutually beneficial cooperation between BRICS countries and allows individual scientists to broaden the range of research, use new tools for S&T cooperation and share best practices.

We discuss recent results obtained in the development of Si(Li), Si p-i-n, CdTe p-i-n and CdZnTe x-ray detectors with Peltier coolers for fabrication of laboratory and portable XRF analyzers. The characteristics of Si(Li) Peltier-cooled detectors are close to those of detectors cooled with the liquid nitrogen and remain the most preferred type of detectors for the tasks of x-ray fluorescence analysis. Considerable success was obtained in the improvement of the characteristics of CdTe p-i-n detectors and CdZnTe detectors with a metal-semiconductor-metal structure, effective in the energy range up to 100 keV. The spectra of all detectors are presented.