SummaryWe present results of the second experiment on the chemical identification of element 112. Similar to the first test in 2000, we aimed at the production of the spontaneously fissioning

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PACS. 25.85. -Fission reactions. PACS. 23.40. -Beta decay; electron and muon capture. PACS. 27.70. -150 d A d 189.

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This paper presents a methodology for calculating exhaust emissions from on-road transport in cities with low-quality traffic data and outdated vehicle registries. The methodology consists of data collection approaches and emission calculation methods. For data collection, the paper suggests using video survey and parking lot survey methods developed for the International Vehicular Emissions model. Additional sources of information include data from the largest transportation companies, vehicle inspection stations, and official vehicle registries. The paper suggests using the European Computer Programme to Calculate Emissions from Road Transport (COPERT) 4 model to calculate emissions, especially in countries that implemented European emissions standards. If available, the local emission factors should be used instead of the default COPERT emission factors. The paper also suggests additional steps in the methodology to calculate emissions only from diesel vehicles. We applied this methodology to calculate black carbon emissions from diesel on-road vehicles in Murmansk, Russia. The results from Murmansk show that diesel vehicles emitted 11.7 tons of black carbon in 2014. The main factors determining the level of emissions are the structure of the vehicle fleet and the level of vehicle emission controls. Vehicles without controls emit about 55% of black carbon emissions.

In 54Cr ion bombardments of targets prepared from enriched lead isotopes the spontaneous fission probability for the isotopes of element 106 formed in the reactions Pb(54Cr, 1,2n)106 was investigated. The spontaneous fission half-life of the doubly-even isotope 26~has been shown to be TSF>~5ms. The half-lives of neighbouring oddmass isotopes have also been estimated: TSF(259106)~>0.1S and Tsv(261106)~>0.4s. The results of the experiments are discussed in comparison with the latest theoretical calculations.In connection with experiments to synthesize element 108 some data are necessary on properties of isotopes with Z=106 which can be produced as a result of the e-decay of the Z=108 nuclides. The nuclear stability itself of element 106 against spontaneous fission (lifetimes TSF ) presents also interest in view of a sharp change in the TSF systematics for Z = 104. For comparison with theory, doubly-even isotopes with Z> 104 (primarily Z= 106) are most informative since for these nuclei the uncertain hindrance factor for Tsv due to oddness is absent. The Tsv data for isotopes of element 106 are rather scarce, they concern only the odd-mass isotopes 259106[1] and 263106 [2]. In our experiments to search for spontaneously fissioning isotopes with Z=106, carried out in 1974, we used the "cold fusion" reactions Pb+54Cr which are most suitable because of the low excitation energy of the compound nucleus (Emi,~lgMeV). In bombardments of the lead isotopes 2~176176 by 54Cr ions of wide range energies up to 290 MeV we detected two spontaneous fission activities with sharply different half-lives: in millisecond (4-10ms) [1] and second (~l.5s) [3] ranges. As a result of a series of control experiments and cross bombardments it was unambiguously established that the activities are both due to isotopes of element 106. The long-lived activity was identified to be the isotope 255104 (the spontaneous fission probability bsv~50%) formed as a result of 2s9106 edecay, and this allowed one to establish the considerable e-decay probability for this isotope of element 106 [3]. The short-lived activity might be due to the isotopes 259106 or 26~ However, the theoretically predicted [4] lifetime TsF (26o106) had to be two orders of magnitude smaller than the known value of TsF 258 (154104) [5], i.e. to be ~0.1ms, which could not be observed in our experiments. The then available data on the probability of neutron emission in "cold fusion" experiments also indicated the most probable value A = 2591 With the construction of the U400 accelerator, the intensity of Ti, Cr, Mn and Fe ion beams increased by several tens of times. Having improved the experimental technique to adjust it to the increased beam intensity and having at our disposal lead isotopes with higher enrichment we turned again to the study of the reactions Pb + 5~Cr with the aim of determining in more detail the properties of both the oddmass and doubly-even isotopes of element 106. The performance of the experiments was similar to that described earlier, and it allowed one to re...

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