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1.
K. Sistemich W. -D. Lauppe T. A. Khan H. Lawin H. A. Selič J. P. Bocquet E. Monnand F. Schussler 《Zeitschrift für Physik A Hadrons and Nuclei》1978,285(3):305-313
Nuclear spectroscopy studies of 51 133 Sb82 have been performed at the recoil fission product separators JOSEF and LOHENGRIN. A tentative level scheme has been established for this nucleus with one proton in addition to the doubly closed shell core132Sn. Two isomeric states with half-lives of 3 and 16 μs have been found at excitation energies of >4300 keV and 4526 keV, respectively. Lower limits of 15/2 are deduced for the spins of these levels. The h11/2 proton state is suggested at 2792 keV in agreement with the systematics of the lighter Z=51 isotopes and the heavier N=82 isotones. Several states have been observed between 4300 and 4600 keV which are probably due to the coupling of the single proton to core-excited states which have energies between 4000 and 4800 keV. 相似文献
2.
The transformation of ethyl 3-{[1-(alkoxycarbonyl)-2-(dimethylamino)ethenyl]amino}2-cyanoprop-2-enoates 2 to dialkyl 3-aminopyrrole-2,4-dicarboxylates 3 in good yields is described. 相似文献
3.
T. A. Khan W. D. Lauppe H. A. Selič H. Lawin G. Sadler M. Shaanan K. Sistemich 《Zeitschrift für Physik A Hadrons and Nuclei》1975,275(3):289-296
A windowless Si(Li) electron detector has been used in conjunction with the gas filled fission product separator JOSEF to study totally converted transitions in Zr and Mo isotopes. The existence of twoβ-decay modes in96Y,98Y and100Nb is confirmed. The half-lives of theβ-decaying levels feeding O 2 + states in96Zr and98Zr are 6.0 ± 0.4 sec and 0.60±0.05 sec respectively. A search for other first excited O 2 + states shows that no such states are apparent in100Zr and104Mo. 相似文献
4.
H. A. Selič G. Sadler T. A. Khan W. -D. Lauppe H. Lawin K. Sistemich E. Monnand J. Blachot J. P. Bocquet F. Schussler 《Zeitschrift für Physik A Hadrons and Nuclei》1979,289(2):197-210
Theβ-decays of99Y and99Zr have been investigated with the two recoil fission product separators JOSEF and LOHENGRIN. Half-lives of 1.51±0.08s and 2.1±0.1s respectively, have been determined. Aβ-decaying isomeric state has been observed in99Y. The level schemes of 40 99 Zr59 and 41 99 Nb58 have been established fromγ-ray spectroscopy. Absoluteγ-intensities have been obtained by means of two independent techniques. Halflives of 293±10 ns for the 251.9 keV state and 10.2±1.5 ns for the 614.0 or 667.2 keV level in99Zr have been measured through delayedβ,γ- andγ,γ-coincidence experiments. Values for the spins and parities of the low lying levels in99Zr are proposed in accordance with the systematics of lighter odd Zr isotopes. Spins and partities are assigned to some levels in99Nb fromγ,γ-angular correlation measurements. In this nucleus there is evidence for three-particle configurations of some excited states, where the odd proton is coupled to two neutrons which are in different orbits. 相似文献
5.
Methyl 2-acetyl-3-{[2-(dimethylamino)-1-(methoxycarbonyl)ethenyl]amino}prop-2-enoate ( 4 ) and phenyl-methyl 2-acetyl-3-{[2-(dimethylamino)-1(methoxycarbonyl)ethenyl]amino}prop-2-enoate ( 5 ) were prepared in three steps from the corresponding acetoacetic esters, and used as reagents for the preparation of N3-protected 3-amino-4H-pyrido[1,2-a]pyrimidin-4-ones 10 – 12 , 5H-thiazolo[3,2-a]pyrimidin-5-one 13 , 4H-pyrido[1,2-a]-pyridin-4-one 19 and 2H-1-benzopyran-2-ones 20 – 23 . Free 3-amino-4H-pyrido[1,2-a]pyrimidin-4-ones 24 – 26 were prepared from 10 – 12 by removal of the 2-(methoxycarbonyl)-3-oxobut-1-enyl or 3-oxo-2-[(phenyl-methoxy)carbonyl]but-1-envl as N-protecting group by various methods. 相似文献
6.
Lovro Seli
Renata Jake Kristina Lampi
Ljubo Goli
Simona Goli
‐Grdadolnik Branko Stanovnik 《Helvetica chimica acta》2000,83(10):2802-2811
Simple and stereoselective syntheses of aplysinopsins and their analogs from either methyl 2‐[(2,2‐disubstituted ethenyl)amino]‐3‐(dimethylamino)prop‐2‐enoates 11 or 5‐[(dimethylamino)methylidene]imidazolidine‐2,4‐diones 20 are described. The structures of products are established by 1H‐ and 13C‐NMR, and NOESY spectroscopy, and X‐ray crystal‐structure analysis. 相似文献
7.
Direct analysis of free bilirubin in human and animal blood serum samples is reported for the first time. A state-of-the-art system comprised of newly developed high-performance liquid chromatography (HPLC) on reverse-phase (RP) C18 support coupled with thermal lens spectrometric detection (TLS), based on excitation at λ = 457.9 nm by an argon laser was used for this purpose. This HPLC-TLS method enabled a baseline separation of all three structural isomers of bilirubin (XIII-α, IX-α and III-α) and the respective degradation products in isocratic mode in fewer than 7 min. The method excels in ultra-high sensitivity with limit of detection (LOD) and limit of quantitation (LOQ) of 90 pM and 250 pM, respectively. Moreover, this method also affords high precision and accuracy, with correlation coefficients R2 > 0.997 over a broad linear range (0.250–150 nM) and R2 = 0.9998 in a concentration range of clinical interest (0.500–25 nM). The method's boosted sensitivity enabled to streamline sample preparation to just one serum ultrafiltration step, which made qualitative evaluation of sample preparation possible for the first time. The performance of the HPLC-TLS method was assessed to have 20-fold enhanced sensitivity when compared to a comparable method incorporating HPLC coupled with diode array detector (DAD), which is also a novel method by itself, and could be applied for free bilirubin determination in patients with elevated bilirubin levels. 相似文献
8.
Andreja Zupančič Valant Lovro Žiberna Yannis Papaharilaou Andreas Anayiotos Georgios C. Georgiou 《Rheologica Acta》2011,50(4):389-402
During the complicated cardiac surgery on a non-beating heart with cardiopulmonary bypass, protection of the heart is accomplished
by injecting cold cardioplegic solutions. In most forms of circulatory shock, it is necessary to immediately restore the circulating
volume. Intravenous solutions of volume expanders, such as hydroxyethyl starch and dextrans, are used to increase the volume
of fluid in the circulating blood. In this work, blood samples of six donors were obtained and used to prepare mixtures with
different volume expanders in concentrations ranging from 10 to 50 vol./vol.%. The flow curves of all mixtures in the temperature
range from 4°C to 37°C were constructed and fitted to the Herschel–Bulkley model, in order to extract the shear thinning and
yield stress parameters. To assess the influence of the observed changes in the rheological properties of blood on the hemodynamics
in arterial vasculature, a realistic three-dimensional rigid-wall computational model was constructed from MRI images of the
right carotid bifurcation obtained in vivo from a healthy male volunteer. The time-varying flow field was numerically computed
using the Newtonian model as well as the Herschel–Bulkley model with the Papanastasiou regularization. The numerical simulations
indicate only moderate changes in the time-averaged flow field that become accentuated when the instantaneous flow field is
considered. We also found that although the influence of temperature, hematocrit, and volume expanders on hemodynamics is
significant, this can primarily be attributed to the changes in the nominal viscosity of the flow medium. 相似文献
9.
Despite their diverse origin, networks of large real-world systems reveal a number of common properties including small-world phenomena, scale-free degree distributions and modularity. Recently, network self-similarity as a natural outcome of the evolution of real-world systems has also attracted much attention within the physics literature. Here we investigate the scaling of density in complex networks under two classical box-covering renormalizations–network coarse-graining–and also different community-based renormalizations. The analysis on over 50 real-world networks reveals a power-law scaling of network density and size under adequate renormalization technique, yet irrespective of network type and origin. The results thus advance a recent discovery of a universal scaling of density among different real-world networks [P.J. Laurienti, K.E. Joyce, Q.K. Telesford, J.H. Burdette, S. Hayasaka, Universal fractal scaling of self-organized networks, Physica A 390 (20) (2011) 3608–3613] and imply an existence of a scale-free density also within–among different self-similar scales of–complex real-world networks. The latter further improves the comprehension of self-similar structure in large real-world networks with several possible applications. 相似文献
10.
K. Kawade G. Battistuzzi H. Lawin H. A. Selič K. Sistemich F. Schussler E. Monnand J. A. Pinston B. Pfeiffer G. Jung 《Zeitschrift für Physik A Hadrons and Nuclei》1982,304(4):293-299
New 0+-levels have been identified at 1,436 keV and 1,859 keV in98Zr through experiments at the fission product separators OSTIS and JOSEF. Half-lives of these levels of 0.69 ns and 0.24 ns, respectively, have been determined from measurements of delayedβ,γ coincidences.E0 transitions depopulating these 0+-levels have been observed. The results are in agreement with the assumption of shape coexistence in98Zr. 相似文献