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排序方式: 共有109条查询结果,搜索用时 15 毫秒
61.
REMEDIOS GONZÁLEZ-LUQUE MANUELA MERCHÁN MERCEDES RUBIO LUIS SERRANO-ANDRÉS BJÖRN O. ROOS MIGUEL-ÁNGEL MIRANDA 《Molecular physics》2013,111(13):1977-1982
The lower excited states of 2-benzoylthiophene have been studied using ab initio quantum chemical methods based on multiconfigurational wave functions. Six singlet and six triplet excited states have been characterized. The geometry has been optimized for the two lowest triplet states, which are responsible for the photoreactivity of the chromophore in the photosensitizing drug tiaprofenic acid. The T1(π → π?) and T2(n → π?) states have been found to be close in energy with the π → π? state slightly lower. The excited states have been characterized using density difference and spin density plots. The different photochemical behaviour of the two triplet states can be rationalized from the theoretical data. 相似文献
62.
Geyer Andrea Renata Cornelio Sousa Varley Dias Silveira Dâmaris 《Accreditation and quality assurance》2019,24(5):351-360
Accreditation and Quality Assurance - Good manufacturing practices (GMP) ensure that products are consistently produced and controlled according to appropriate quality standards. This study aimed... 相似文献
63.
BJÖRN O. ROOS 《Molecular physics》2013,111(1-2):87-91
Results are presented from a theoretical study of the × 6Σ+, A 6Σ+ and 6Δ electronic states of CrH using multiconfiguration second-order perturbation theory in the multi-state formalism (MS-CASPT2). It is shown that the results for the spectroscopic constants and radiative lifetimes for the A state are in agreement with experiment and an earlier multireference configuration interaction study only if the two close lying × and A states are allowed to interact at a level of approximation that includes dynamic correlation. 相似文献
64.
Larry Q. Reyes Buu Dao Wouter Vogel Johan Bijleveld Sam Tucker Steve Christensen Jeffrey Wiggins Theo Dingemans Russell J. Varley 《先进技术聚合物》2020,31(4):827-837
Isomeric tri‐aryl ketone amines, 1,3‐bis(3‐aminobenzoyl)benzene (133 BABB), 1,3‐bis(4‐aminobenzoyl)benzene (134 BABB), and 1,4‐bis(4‐aminobenzoyl)benzene (144 BABB) are synthesized and cured with diglycidyl ether of bisphenol A and diglycidyl ether of bisphenol F in this work. Differential scanning calorimetry and near‐infrared spectroscopy reveal higher rate constants and enhanced secondary amine conversion with increasing para substitution attributed to resonance effects and the electron withdrawing nature of the carbonyl linkages. Glass transition temperatures increase from 133 BABB to 134 BABB, but decrease modestly for the 144 BABB hardener. With increasing para substitution, the flexural modulus and strength both decrease while the strain to failure increases but all BABB amines displaying higher mechanical properties than the corresponding 4,4‐diaminodiphenyl sulfone (44 DDS) networks. The thermal stability of the BABB networks is found to be modestly lower than 44 DDS, but char yields are significantly higher. Changes in thermal and mechanical properties are described in terms of molecular structure and equilibrium packing density. 相似文献
65.
R. Lucas M.-G. Porquet Ts. Venkova I. Deloncle M. Houry Ch. Theisen A. Astier A. Bauchet S. Lalkovski G. Barreau N. Buforn T.P. Doan L. Donadille O. Dorvaux J. Durell Th. Ethvignot B.P.J. Gall D. Grimwood W. Korten Y. Le Coz M. Meyer A. Minkova A. Prévost N. Redon A. Roach N. Schulz A.G. Smith O. Stézowski B.J. Varley 《The European Physical Journal A - Hadrons and Nuclei》2002,15(3):315-323
The 115, 117, 119, 121In nuclei have been produced as fission fragments in three reactions induced by heavy ions: 12C + 238U at 90MeV bombarding energy, 18O + 208Pb reaction at 85MeV, and 31P + 176Yb at 152MeV. Their level schemes have been built from gamma-rays detected using the EUROBALL III and IV arrays. High-spin
states of 117, 119, 121In nuclei have been identified for the first time. Moreover, isomeric states lying around 2.5MeV have been established in
119, 121In from the delayed coincidences between the fission fragment detector SAPhIR and the gamma array. Most of the observed states
can be described by coupling a proton g
9/2 hole to a Sn core, while the intruder band based on an orbital from the π[g
7/2/d
5/2] sub-shells behaves as the ground-state band of neighbouring Cd isotopes.
Received: 24 May 2002 / Accepted: 11 June 2002 / Published online: 19 November 2002
RID="a"
ID="a"e-mail: porquet@csnsm.in2p3.fr
RID="b"
ID="b"Present address: CEA-DIF, DAM/DCRE/SDE/LDN, 91680 Bruyères-le-Chatel, France.
RID="c"
ID="c"Present address: CSNSM IN2P3-CNRS and Université Paris-Sud 91405 Orsay, France.
RID="d"
ID="d"Present address: CEA/Saclay, DSM/DAPNIA/SPhN, 91191 Gif-sur-Yvette Cedex, France.
Communicated by D. Schwalm 相似文献
66.
W.?UrbanEmail author T.?Rzaca-Urban J.?L.?Durell W.?R.?Phillips A.?G.?Smith B.?J.?Varley I.?Ahmad N.?Schulz 《The European Physical Journal A - Hadrons and Nuclei》2004,20(3):381-384
The ground-state band in 110Mo has been observed for the first time. The band, comprising six levels, has been populated in the spontaneous fission of 248Cm and studied by means of prompt
-ray spectroscopy using the EUROGAM2 array. The ratio
suggests that the deformation of 110Mo is smaller than that in 108Mo but may stabilize at higher neutron number, where an oblate shape is expected. The new data suggests that the deformation of Sr and Zr isotopes decreases above neutron number N = 64.Received: 23 February 2004, Published online: 2 June 2004PACS:
23.20.Lv
transitions and level energies - 21.60.Cs Shell model - 25.85.Ca Spontaneous fission - 27.60. + j
相似文献
67.
68.
69.
A. Nowak W. Urban W. Kurcewicz T. Rząca-Urban H. Mach B. Fogelberg J.L. Durell M.J. Leddy M.A. Jones W.R. Phillips A.G. Smith B.J. Varley M. Bentaleb E. Lubkiewicz N. Schulz I. Ahmad L.R. Morss 《The European Physical Journal A - Hadrons and Nuclei》1999,4(1):1-3
132Te was produced via the 232Th (α, fission) reaction at the Variable Energy Cyclotron , Calcutta. 132Te was separated in carrier-free form from the fission products by radiochemical separation and the half-lives for the 50
keV and 162 keV states of 132I were determined to be 2.94±0.11 ns and 0.55±0.04 ns respectively. The present results differ significantly from the previously
reported half-lives of 7.14 ns and 3.57 ns for the 50 keV and 162 keV states respectively.
Received: 28 July 1998 / Revised version: 23 September 1998 相似文献
70.
A. Korgul W. Urban T. Rząca-Urban M. Rejmund J.L. Durell M.J. Leddy M.A. Jones W.R. Phillips A.G. Smith B.J. Varley N. Schulz M. Bentaleb E. Lubkiewicz I. Ahmad L.R. Morss 《The European Physical Journal A - Hadrons and Nuclei》2000,7(2):167-176
Excited states in the neutron-rich, N=84 nuclei 134Sn, 136Te and 138Xe, populated in the spontaneous fission of 248Cm, were studied to medium spins using the EUROGAM2 array. OXBASH code calculations support the experimental identification
of maximum aligned configurations in these isotopes. Empirical shell model calculations agree with the proposed excitation
energy of the neutron h9/2 excitation in the 132Sn region. A discrepancy between the observed and calculated excitation energy of the Iπ= 12+ level in 136Te indicates possible admixtures of collective excitations in this nucleus. Clear signs of collective excitations are observed
in 138Xe.
Received: 10 November 1999 / Revised version: 22 December 1999 相似文献