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71.
72.
G. de Angelis T. Martinez A. Gadea N. Marginean E. Farnea E. Maglione S. Lenzi W. Gelletly C.A. Ur D.R. Napoli Th. Kroell S. Lunardi B. Rubio M. Axiotis D. Bazzacco A.M. Bizzeti Sona P.G. Bizzeti P. Bednarczyk A. Bracco F. Brandolini F. Camera D. Curien M. De Poli O. Dorvaux J. Eberth H. Grawe R. Menegazzo G. Nardelli J. Nyberg P. Pavan B. Quintana C. Rossi Alvarez P. Spolaore T. Steinhart I. Stefanescu O. Thelen R. Venturelli 《The European Physical Journal A - Hadrons and Nuclei》2001,12(1):51-55
Gamma ray transitions de-exciting states in the N = Z nucleus 70Br have been identified for the first time using the GASP and EUROBALL arrays coupled with ancillary detectors. The level
scheme of 70Br has been established by means of particle-gated γ-γ and γ-γ-γ coincidences. The Coulomb energy differences between isobaric
analogue states in 70Br and 70Se show a deviation from the expected behaviour which could be related to dripline effects.
Received: 18 July 2001 / Accepted: 25 September 2001 相似文献
73.
C. Mazzocchi Z. Janas J. Döring M. Axiotis L. Batist R. Borcea D. Cano-Ott E. Caurier G. de Angelis E. Farnea A. Faßbender A. Gadea H. Grawe A. Jungclaus M. Kapica R. Kirchner J. Kurcewicz S.M. Lenzi T. Martínez I. Mukha E. Nácher D.R. Napoli E. Roeckl B. Rubio R. Schwengner J.L. Tain C.A. Ur 《The European Physical Journal A - Hadrons and Nuclei》2001,12(3):269-277
By using the fusion-evaporation reaction 28Si(36Ar,p3n) and spectroscopy of β-delayed γ-rays and charged particles on mass-separated sources, β-decay properties of the neutron-deficient
isotope 60Ga were studied for the first time. The half-life of 60Ga was determined to be 70(15) ms, and, based on βγγ coincidences, the isobaric-analogue state in 60Zn was identified at 4851.9(7) keV. A semiempirical proton separation energy value of 40(70) keV was deduced for 60Ga. The experimental results on half-life, mass excess, proton separation energy, and structure of the 60Zn daughter states are discussed in comparison with various model predictions, including large-scale shell model calculations.
Received: 4 September 2001 / Accepted: 12 November 2001 相似文献
74.
V. N. Larina V. F. Ur’yash D. S. Kushch 《Russian Journal of Physical Chemistry A, Focus on Chemistry》2012,86(12):1776-1778
The standard enthalpies of combustion and formation of cellulose acetates with different degrees of acetylation are determined. It is established that there is a proportional dependence of these thermochemical characteristics vs. the degree of acetylation, weight fraction of bonded acetic acid, and molar mass of the repeating unit of cellulose acetates. 相似文献
75.
A. S. Gordetsov S. V. Zimina V. F. Ur’yash E. M. Moseeva 《Russian Journal of General Chemistry》2013,83(2):299-302
At the interaction of bis (η5-cyclopentadienyl)vanadium with iodobenzoic acid or trimethylsilyl o-iodobenzoate in toluene depending on the ratio of the initial reagents bis(η5-cyclopentadienyl)vanadium(o-iodobenzoate) or η5-cyclopentadienylvanadium-bis-o-iodobenzoate were obtained in high yields. The latter was also formed in the reaction of bis(η5-cyclopentadiene)vanadium dihloride with trimethylsilyl o-iodobenzoate. 相似文献
76.
Ixone Esnal Arlette Urías‐Benavides Dr. C. F. Azael Gómez‐Durán Dr. Carlos A. Osorio‐Martínez Prof. Inmaculada García‐Moreno Prof. Angel Costela Dr. Jorge Bañuelos Nerea Epelde Prof. Iñigo López Arbeloa Dr. Rongrong Hu Prof. Ben Zhong Tang Prof. Eduardo Peña‐Cabrera 《化学:亚洲杂志》2013,8(11):2691-2700
A thorough study of the photophysical and laser properties of 8‐aminoboron dipyrromethene dyes was undertaken to determine the role of amine substitution and spatial disposition on the properties of the dyes. It was found that the fluorescent and laser response varied significantly. Although primary amines give rise to highly fluorescent products at the blue edge of the visible region, secondary amines yield nonfluorescent analogues in polar media. The crystal structures of two analogues are reported and described. Steric hindrance and the higher electron‐releasing ability of the amine favor the formation of a quenching intramolecular charge‐transfer state. Accordingly, boron dipyrromethene derivatives with primary amines exhibited laser emission with efficiencies of up to 44 %. Besides, the more efficient derivative was also the most photostable, leading to a significant improvement in the lasing performance with regard to previously reported 8‐aminoboron dipyrromethene derivatives. An increase in the solvent polarity, and mainly the presence of tertiary cyclic amines, led to a dramatic decrease or even the loss of the laser action. 相似文献
77.
Khalil Ur Rehman Muhammad Awais Arif Hussain Nabeela Kousar Muhammad Yousaf Malik 《Mathematical Methods in the Applied Sciences》2019,42(1):24-38
A speculative investigation has been presented to explore the salient features of magnetohydrodynamic (MHD) Prandtl‐Eyring nanofluid over stretching surface. Effects of Navier slip and convective boundary conditions are included in flow configuration. The effects of higher order chemical reactions along with Nield conditions are assumed in the concentration of nanoparticles. The mathematical modelling of the said flow problem accomplished the nonlinear partial differential equations along with appropriate boundary conditions. The nondimensional form of governing problem is yielded with the aid of similarity variables. The pivotal physical quantities, ie, velocity, temperature, and concentration (in nondimensional form), within boundary layer region are computed with shooting technique. The physical significance of flow controlling parameters on velocity, temperature, and concentration is illustrated through graphs. Additionally, thermophysical aspects of fluid near stretching surface (wall friction factor, wall heat flux, and wall mass flux) are instantiated graphically. A comparison of the current solution with reported data is established to validate the accuracy of adapted procedure. It is observed that the current findings agree with existing data. This led to confidence on adapted numerical procedure. 相似文献
78.
D. Bucurescu D. Barnéoud R. Béraud G. Cata-Danil T. von Egidy A. Emsallem J. Genevey A. Gizon J. Gizon C. F. Liang P. Paris C. A. Ur B. Weiss 《Zeitschrift für Physik A Hadrons and Nuclei》1994,350(1):3-4
Excited states of 108 Te were populated in the 54 Fe + 58 Ni (270 MeV) reaction using the NORDBALL detector array equipped with charged-particle and neutron detector systems for reaction channel separation. Gamma rays belonging to the neutron deficient nucleus 108 Te were identified for the first time. On the basis of γγ-coincidence and angular correlation relations a level scheme was constructed with tentative spin and parity assignments. The structure of the nucleus is discussed in the framework of systematics of heavier Te nuclei. 相似文献
79.
S. Thummerer W. von Oertzen Tz. Kokalova H. G. Bohlen B. Gebauer A. Tumino T. N. Massey G. de Angelis M. Axiotis A. Gadea Th. Kröll N. Marginean D. R. Napoli M. De Poli C. Ur D. Bazzacco S. M. Lenzi C. Rossi Alvarez S. Lunardi R. Menegazzo P. G. Bizzeti A. M. Bizzeti-Sona 《Physics of Atomic Nuclei》2003,66(8):1428-1433
The reactions 16O(7Li, 2n) and 16O(7Li, np) populating 21Na and 21Ne have been studied at E L=27 MeV using the GASP γ-detector array. The level schemes for 21Na and 21Ne have been extended to higher spin. The population of the bands with K=3/2 and 1/2, forming parity doublets, are compared. Preferential E1 decay between bands of opposite parity is observed in agreement with the octupole scenario. The structure of these bands can be interpreted as consisting of an instrinsic asymmetric (4He + 16O) structure with octupole deformation. 相似文献
80.
Marko Uršič 《Acta Analytica》2002,17(1):53-67
This paper deals with one of the basic philosophical questions in modern cosmology: can the so-called “Anthropic Principle”,
considered as an alternative to the classical teleology of creation, be an adequate explanation of the evidence that our universe
is “fine-tuned” for the emergence of life and consciousness. The main problem with this principle is not its presumed teleology,
as it is sometimes wrongly supposed, but quite the contrary: its intention to avoid teleological explanations by including
the existence of many universes (“multiverse”) into extended cosmological models. After having compared logical and cosmological
many-worlds concepts, this paper reaches the conclusion that the ontological reality of the “multiverse” is an even more problematic
presupposition than some properly revised version of teleological causality. This in itself does not imply the classical theistic
explanation of creation, since it also yields a pantheistic explanation of the emergence of life and consciousness in our
universe. 相似文献