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31.
A. Kankainen V. S. Kolhinen V. -V. Elomaa T. Eronen J. Hakala A. Jokinen A. Saastamoinen J. Äystö 《The European Physical Journal A - Hadrons and Nuclei》2012,48(4):47
Penning-trap measurements on stable 92, 94-98, 100Mo isotopes have been performed with relative accuracy of \(\ensuremath 1\cdot 10^{-8}\) with the JYFLTRAP Penning-trap mass spectrometer by using 85Rb as a reference. The Mo isotopes have been found to be about 3keV more bound than given in the Atomic Mass Evaluation 2003 (AME03). The results confirm that the discrepancy between the ISOLTRAP and JYFLTRAP data for 101-105Cd isotopes was due to an erroneous value in the AME03 for 96Mo used as a reference at JYFLTRAP. The measured frequency ratios of Mo isotopes have been used to update mass-excess values of 30 neutron-deficient nuclides measured at JYFLTRAP. 相似文献
32.
Jouni Peltoniemi Teemu Hakala Juha Suomalainen Eetu Puttonen 《Journal of Quantitative Spectroscopy & Radiative Transfer》2009,110(17):1940-1953
The bidirectional reflectance factor and degree of linear polarisation of selected snow, soil, and gravel types have been measured using Finnish geodetic institute field goniospectropolariphotometer (FIGIFIGO). It was observed that with all measured samples the degree of linear polarisation is weakest 0–30 backwards from nadir, turning 1–5% negative in the backward direction, and growing larger (5–50%) in the forward and Brewster directions. Polarisation was found to be inversely but non-linearly proportional to reflectance. In addition, a wavelength-dependent trend was found to exist in some data, but in general, the wavelength dependence was smooth. Dry old snow polarises clearly more than melting snow or new snow. White gravel polarises somewhat similarly to snow in visible region, and black gravel resembles snow in infrared.The authors conclude that polarisation observations may be useful in land surface remote sensing, but that only far-forward angles (60–70) contain a strong enough signal for easy interpretation. The polarisation spectrum brings little additional information to reflection spectrum, but in conditions where the reflectance spectrum cannot be accurately normalised or incident irradiation is not known, polarisation spectrum could still be usable. The directional signal is strong and may yield refractive index or microstructure, and must be understood in any application. Polarisation near nadir is low for all known samples, and can thus be safely ignored with most non-polarised imaging applications. However, for accurate atmospheric polarimetry, e.g. by polarisation and directionality of the earth's reflectances (POLDER) or aerosol polarimetry sensor (APS) sensors, it is recommended to take into account land surface polarisation. 相似文献
33.
Algora A Jordan D Taín JL Rubio B Agramunt J Perez-Cerdan AB Molina F Caballero L Nácher E Krasznahorkay A Hunyadi MD Gulyás J Vitéz A Csatlós M Csige L Aysto J Penttilä H Moore ID Eronen T Jokinen A Nieminen A Hakala J Karvonen P Kankainen A Saastamoinen A Rissanen J Kessler T Weber C Ronkainen J Rahaman S Elomaa V Rinta-Antila S Hager U Sonoda T Burkard K Hüller W Batist L Gelletly W Nichols AL Yoshida T Sonzogni AA Peräjärvi K 《Physical review letters》2010,105(20):202501
The β feeding probability of (102,104,105,106,107)Tc, 105Mo, and 101Nb nuclei, which are important contributors to the decay heat in nuclear reactors, has been measured using the total absorption technique. We have coupled for the first time a total absorption spectrometer to a Penning trap in order to obtain sources of very high isobaric purity. Our results solve a significant part of a long-standing discrepancy in the γ component of the decay heat for 239Pu in the 4-3000 s range. 相似文献
34.
H. Penttil? P. Karvonen T. Eronen V. -V. Elomaa U. Hager J. Hakala A. Jokinen A. Kankainen I. D. Moore K. Per?j?rvi S. Rahaman S. Rinta-Antila V. Rubchenya A. Saastamoinen T. Sonoda J. ?yst? 《The European Physical Journal A - Hadrons and Nuclei》2010,44(1):147-168
A novel method to determine independent yields in particle-induced fission employing the ion guide technique and ion counting after a Penning trap has been developed. The method takes advantage of the fact that a Penning trap can be used as a precision mass filter, which allows an unambiguous identification of the fission fragments. The method was tested with 25MeV and 50MeV proton-induced fission of 238U . The data is internally reproducible with an accuracy of a few per cent. A satisfactory agreement was obtained with older ion guide yield measurements in 25MeV proton-induced fission. The results for Rb and Cs yields in 50MeV proton-induced fission agree with previous measurements performed at an isotope separator equipped with a chemically selective ion source. 相似文献
35.
Hakala J Rahaman S Elomaa VV Eronen T Hager U Jokinen A Kankainen A Moore ID Penttilä H Rinta-Antila S Rissanen J Saastamoinen A Sonoda T Weber C Aystö J 《Physical review letters》2008,101(5):052502
Atomic masses of the neutron-rich isotopes (76-80)Zn, (78-83)Ga, (80-85)Ge, (81-87)As, and (84-89)Se have been measured with high precision using the Penning trap mass spectrometer JYFLTRAP at the IGISOL facility. The masses of (82,83)Ga, (83-85)Ge, (84-87)As, and 89Se were measured for the first time. These new data represent a major improvement in the knowledge of the masses in this neutron-rich region. Two-neutron separation energies provide evidence for the reduction of the N=50 shell gap energy towards germanium (Z=32) and a subsequent increase at gallium (Z=31). The data are compared with a number of theoretical models. An indication of the persistent rigidity of the shell gap towards nickel (Z=28) is obtained. 相似文献
36.
Eronen T Elomaa VV Hager U Hakala J Hardy JC Jokinen A Kankainen A Moore ID Penttilä H Rahaman S Rinta-Antila S Rissanen J Saastamoinen A Sonoda T Weber C Aystö J 《Physical review letters》2008,100(13):132502
Using a new fast cleaning procedure to prepare isomerically pure ion samples, we have measured the beta-decay Q(EC) values of the superallowed beta emitters 5(0)Mn and (54)Co to be 7634.48(7) and 8244.54(10) keV, respectively, results which differ significantly from the previously accepted values. The corrected Ft values derived from our results strongly support new isospin-symmetry-breaking corrections that lead to a higher value of the up-down quark mixing element V(ud) and improved confirmation of the unitarity of the Cabibbo-Kobayashi-Maskawa matrix. 相似文献
37.
A. Bey B. Blank G. Canchel C. Dossat J. Giovinazzo I. Matea V. -V. Elomaa T. Eronen U. Hager J. Hakala A. Jokinen A. Kankainen I. Moore H. Penttilä S. Rinta-Antila A. Saastamoinen T. Sonoda J. Äystö N. Adimi G. de France J. -C. Thomas G. Voltolini T. Chaventré 《The European Physical Journal A - Hadrons and Nuclei》2008,36(2):121-126
Beta-decay branching ratios of 62Ga have been measured at the IGISOL facility of the Accelerator Laboratory of the University of Jyv?skyl?. 62Ga is one of the heavier T
z = 0 , 0+ → 0+ β -emitting nuclides used to determine the vector coupling constant of the weak interaction and the Vud quark-mixing matrix element. For part of the experimental studies presented here, the JYFLTRAP facility has been employed
to prepare isotopically pure beams of 62Ga . The branching ratio obtained, BR = 99.893(24) %, for the super-allowed branch is in agreement with previous measurements and allows to determine the ft value and the universal Ft value for the super-allowed β -decay of 62Ga . 相似文献
38.
Kunnari TJ Ylihonko KP Klika KD Mäntsälä PI Hakala JM 《The Journal of organic chemistry》2000,65(10):2851-2855
The genetic engineering of antibiotic-producing Streptomyces strains is an approach that is emerging and ready to become established as a successful methodology in developing analogues of the original, pharmaceutically important, natural products obtained from the organisms. The current report highlights this succes by demonstrating the high-level production of novel anthracyclines. The biosynthetic pathways of the nogalamycin-producing Streptomyces nogalater and the aclacinomycin-producing S. galilaeus were combined by transferring the genes of S. nogalater polyketide synthetase into a nonproducing S. galilaeus mutant. The resulting anthracycline antibiotics that were produced possessed structural features characteristic of compounds from both of the undoctored Streptomycesstrains. 相似文献
39.
[reaction: see text] Novel nucleosidic phosphoramidite blocks were synthesized by a Mitsunobu reaction between 2'-deoxy-5'-O-(4,4'-dimethoxytrityl)uridine and a primary alcohol containing a conjugate group in its structure (a protected functional group, an organic dye, or a precursor of a lanthanide(III) chelate) followed by phosphitylation. They were used in machine-assisted DNA synthesis in the standard manner. A slightly modified deprotection procedure was used for the preparation of oligonucleotide conjugates tethered to lanthanide(III) chelates. For the latter application one non-nucleosidic block was also synthesized. 相似文献
40.
Practical detection limits were 2 and 10 μg l?1 vanadium for pyrolyte graphite-furnace a.a.s. and d.c.p.-a.e.s., respectively, which allowed screening for urinary vanadium (? 10 μg ?in ? subjects, by direct measurements. Extraction of vanadium with ammonium 1?inecarbodithioate into 4-methylpentan-2-one gave detection limits of 0.5 and ? μg l?1 vanadium, respectively, for the two techniques. 相似文献