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We present first preliminary results of a novel method for measuring independent isotopic fission yields (IIFYs) of spontaneous fission (SF) via direct mass measurements, at the FRS Ion Catcher (FRS-IC) at GSI. Fission products were generated from a 252Cf source installed in a cryogenic stopping cell, and were identified and counted with the multiple-reflection time-of-flight mass spectrometer (MR-TOF-MS) of the FRS-IC, utilizing well-established measurement and data analysis methods. The MR-TOF-MS resolves isobars unambiguously, even with limited statistics, and its non-scanning nature ensures minimal relative systematic uncertainties amongst fission products. The analysis for extracting IIFYs includes isotope-dependent efficiency corrections for all components of the FRS-IC. In particular, we applied a self-consistent technique that takes into account the element-dependent survival efficiencies in the CSC, due to chemical reactions with the buffer gas. Our IIFY results, which cover several tens of fission products in the less-accessible high-mass peak (Z = 56 to 63) down to fission yields at the level of 10−5, are generally similar to those of the nuclear database ENDF/B-VII.0. Nevertheless, they reveal some structures that are not observed in the database smooth trends. These are the first results of a planned campaign to investigate IIFY distributions of spontaneous fission at the FRS-IC. Upcoming experiments will extend our results to wider Z and N ranges, lower fission yields, and other spontaneously-fissioning actinides.

Mass measurements of the $^{69}$As, $^{70,71}$Se and $^{71}$Br isotopes, produced via fragmentation of a $^{124}$Xe primary beam at the FRS at GSI, have been performed with the multiple-reflection time-of-flight mass spectrometer (MR-TOF-MS) of the FRS Ion Catcher with an unprecedented mass resolving power of almost 1,000,000. For the $^{69}$As isotope, this is the first direct mass measurement. A mass uncertainty of 22 keV was achieved with only 10 events. For the $^{70}$Se isotope, a mass uncertainty of 2.6 keV was obtained, corresponding to a relative accuracy of $\delta$m/m = 4.0$\times 10^{-8}$, with less than 500 events. The masses of the $^{71}$Se and $^{71}$Br isotopes were measured with an uncertainty of 23 and 16 keV, respectively. Our results for the $^{70,71}$Se and $^{71}$Br isotopes agree with the 2016 Atomic Mass Evaluation, and our result for the $^{69}$As isotope resolves the discrepancy between previous indirect measurements. We measured also the mass of $^{14}$N$^{15}$N$^{40}$Ar (A=69) with a relative accuracy of $\delta$m/m = 1.7$\times 10^{-8}$, the highest yet achieved with a MR-TOF-MS. Our results show that the measured restrengthening of the proton-neutron interaction ($\delta$V$_{pn}$) for odd-odd nuclei at the N=Z line above Z=29 (recently extended to Z=37) is hardly evident at N-Z=2, and not evident at N-Z=4. Nevertheless, detailed structure of $\delta$V$_{pn}$ along the N-Z=2 and N-Z=4 lines, confirmed by our mass measurements, may provide a hint regarding the ongoing $\approx$500 keV discrepancy in the mass value of the $^{70}$Br isotope, which prevents including it in the world average of ${Ft}$-value for superallowed 0$^+\rightarrow$ 0$^+$ $\beta$ decays. The reported work sets the stage for mass measurements with the FRS Ion Catcher of nuclei at and beyond the N=Z line in the same region of the nuclear chart, including the $^{70}$Br isotope., Comment: 11 pages, 4 figures, accepted for publication at Physical Review C

State-of-the-art ships focus on enhancing vessel performance, lower emissions, optimize space on board and save fuel. This paper describes an innovative marine solution in which the same electric machine can be operated as a conventional shaft generator and also as a variable speed propulsion motors. The distinctive design (patent pending) consists of a special synchronous machine provided with two separate exciters (one AC and the second DC) each capable to energize the same main rotor field through two independent rotating rectifiers. Whilst the conventional PTO/PTI systems may use the synchronous machine in a very narrow speed range - the presence of the independent AC exciter allows to energize the main field from zero rpm. The propeller can therefore be fully electrically operated. The dual-excitation arrangement is described in the paper highlighting its benefits compared to the conventional design. Numerical simulations are presented to assess the possible electromagnetic interactions between the two coaxial rotating excitation systems. Extensive testing campaign validated the design expectations.

Mini-Micro hydro power plants are widely used as they represent the best tradeoff among energy requirements, limited environmental-social impact, high system efficiency and reduced investments. The hydro generators are an essential part of the system and their performances effect the overall power plant quality goals. The direct-drive configuration (turbine and generator running at the same mechanical speed) will increase the system efficiency, save space in the hydro station, reduce maintenance, preserve the environment by limiting the lubricant usage in the power station. Adequate mechanical arrangements are necessary to match speed/stress constraints as well as electric/high efficiency performance requirements. In the paper a description on the possible solutions for mini hydroelectric generators is proposed.

Generators for essential and emergency service can be provided with special features to guarantee reliable and safe operation in all possible operating conditions. The paper illustrates possible enhanced capabilities for industrial, nuclear, marine and navy applications.

Lavandula x intermedia Emeric ex Loisel. 'Budrovka' is an indigenous cultivar of lavandin which has been widely cultivated in Croatia as an essential oil crop. Our previous studies revealed strong antioxidant and antibacterial activities of its various extracts [1, 2]. Continuing our evaluation of biomedical potential of lavandin ’Budrovka’, the present work focuses on the investigation of antifungal activity. For this purpose, liquid ethanolic extracts were prepared from different plant parts: flowers, inflorescence stalks and leaves. Employing the agar-well diffusion method, the extracts were screened for antifungal activity against eight yeast strains (Candida albicans, C. glabrata, C. krusei, C. kefyr, C. tropicalis, Cryptococcus neoformans, Blastoschizomyces capitatus and Hansenula anomala) and five molds (Aspergillus fumigatus, A. niger, Fusarium oxysporum, Penicillium citrinum and Trichoderma viride). Overall, the tested extracts were more effective against yeasts then molds. The measured zones of inhibition of fungal growth strongly indicated that the antifungal constituents reside primarily in the flower (ZI: 10-21 mm), whereas the inflorescence stalk and leaves extracts exhibited considerably weaker activity (ZI ≤ 10). Minimal inhibitory concentrations (MIC, vol%) and minimal fungicidal concentrations (MFC, vol%) for each strain were determined by the broth dilution assay. Results obtained for flower, leaf and inflorescence stalk extracts revealed that Candida krusei was the most sensitive tested strain (MIC: 0.05, 8 and 9%, respectively), while Aspergillus niger was the most resistant (MIC: 4, 30 and 35%, respectively). In conclusion, the present study highlighted the antifungal potential of Lavandula x intermedia 'Budrovka' flowers. References: 1. Blažeković, B., Vladimir-Knežević, S. (2008) Planta Med. 74:951. 2. Blažeković, B., Pepeljnjak, S., Stanić, G., Žutić, I. (2005) Book of Abstracts of 53 rd Annual Congress of the Society for Medicinal Plant Research. Firenca. Societa italiana di fitochimica, 145.