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81.
Doina Bunaciu Viorica Florescu Daniela Fluerasu R. H. Pratt 《Zeitschrift für Physik A Hadrons and Nuclei》1981,301(2):109-118
An analytic method is presented for evalution of internal conversion coefficients (ICC) in inner shells of neutral or ionized atoms. Analytic formulas for ICC are given which include electron screening and static nuclear size effects. Predictions have also been obtained from these formulas for point Coulomb ICC or for screening effects included only in bound state normalization. Very good agreement with full numerical calculations is found, except in those cases where the formation region of the ICC is not well inside the atom. While the discussion in this paper concerns mediumZ elements (30<Z<80) and not too low energy, the method can be extended to other situations. The method is suited also for ICC of the inner shells of ionized atoms, even for very high degree of ionization. 相似文献
82.
Maria Viorica Stefanescu Massimiliano Ferrara Anton Stefanescu 《Optimization Letters》2013,7(5):855-870
(Φ, ρ)-invexity and (Φ, ρ) w -invexity generalize known invexity type properties and have been introduced with the intent of extending most of theoretical results in mathematical programming. Here, we push this approach further, to obtain authentic extensions of previously known optimality and duality results in multiobjective programming. 相似文献
83.
Viorica Lopez-Avila Janet Benedicto Emi Baldin Werner F. Beckert 《Journal of separation science》1991,14(9):601-607
Thirty five nitroaromatic compounds (currently listed in EPA Method 8091) and 1,4-naphthoquinone have been separated on DB-5–DB-1701 and SPB-5–SPB-1701 column pairs, which were in each case connected to an inlet splitter and separate electron capture detectors. Retention times are included for 21 additional compounds evaluated for their suitability as internal standards and/or surrogate compounds for incorporation into Method 8091. Method reproducibility and linearity are discussed, and results are presented for extracts of two real samples spiked with the 35 nitroaromatic compounds and 1,4-naphthoquinone and analyzed using the dual-column-dual-detector arrangement. 相似文献
84.
Study by thermal methods on the materials obtained by dye removal from waste waters with beech flour
Lucia Odochian Viorica Dulman M. Dumitraş A. Pui 《Journal of Thermal Analysis and Calorimetry》2007,89(2):625-631
The study is devoted to the characterization by both TG-DTG analysis and FTIR spectroscopy of beech flour, dyes and the sorbent-dyes
products obtained through retention of the dyes from aqueous solution on the beech flour, to the aim of obtaining information
on the nature of dyes’ retention, thermal behavior of the sorbent-dye materials as well as on their possible upgrading as
fuel.
Thermal analysis led to the conclusion that the mechanism of thermo-oxidative degradation is specific and the retention of
dyes occurs on cellulose from beech flour. The nature of the bonds involved in dyes’ retention is also investigated by FTIR
analysis, which evidences that dyes retention on cellulose is realized through hydrogen bonding between the NH and, respectively,
OH groups from dye molecule and the oxygen atoms from cellulose. Involvement of the non-participating electrons of the nitrogen
and, respectively, oxygen atoms of these groups in the extended electronic conjugation with aromatic nuclei strongly influences
the capacity of the amino and, respectively, hydroxyl groups of forming hydrogen bonds, thus achieving dyes fixation on the
sorbent. DTA analysis led to the conclusion that an improvement in the quality of the sorbent-dye materials as fuels is possible,
as compared to untreated beach flour, as a result of the modification of the cellulosic fibers in the process of dyes retention. 相似文献
85.
Aurelia Cionga Viorica Florescu 《Zeitschrift für Physik D Atoms, Molecules and Clusters》1986,2(1):49-59
We consider Rayleigh scattering from a hydrogenlike atom in an arbitrary excitedn=2 state, and we investigate theoretically the dependence of the scattered radiation intensity and Stokes parameters on the state multipoles for the case of unpolarized incident radiation. Because in then=2 case Rayleigh scattering can not be accompanied by the change of the electron angular momentum, only 10 out of the 16 state multipoles influence the scattered radiation attributes. Our study reveals the existence of a measurable quantity which is determined only by Rayleigh scattering from 2p states. For the particular case of excitation by electron impact, some quantitative predictions are made, at the photon scattering angle ?=π/2, based on values for the state multipoles extracted from the literature (Blum and Kleinpoppen, Band). The vicinity of Balmer α and Lyman α resonances are studied in detail. 相似文献
86.
Petru Jebelean Dumitru Motreanu Viorica Venera Motreanu 《Mathematische Nachrichten》2008,281(9):1283-1293
In this paper we establish the solvability and approximation of a general inequality problem by means of a sequence of problems satisfying some compatibility conditions with respect to the initial one. The setting allows to unify and extend various existence results in the smooth and nonsmooth analysis. The approach mainly relies on Galerkin like approximations, pseudo‐monotone operators and topics from nonsmooth analysis. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim) 相似文献
87.
The thermal behaviour of EPDM/NR blends was studied by differential scanning calorimetry over the temperature range 335–435 K. O'Neill's method (O'Neill MG. Anal Chem 1964;36:1238) was used for calculating the specific heat capacity with aluminia as standard. The presence of natural rubber induces a marked thermal instability because of the high content of double bonds. The contribution of each component to the Cp of the tested polymer systems is discussed. The law of reciprocal affinity, the linear contribution of components to the specific heat capacity is followed by EPDM/NR blends. The influence of natural rubber on the thermal behaviour of tested mixtures was assessed by oxygen uptake method and the first derivative procedure reveals the sequence in thermal stability of ethylene-propylene-diene/natural rubber compounds. 相似文献
88.
89.
90.
In this paper we solve an infinite-horizon linear quadratic control problem for a class of differential equations with countably infinite Markov jumps and multiplicative noise. The global solvability of the associated differential Riccati-type equations is studied under detectability hypotheses. A nonstochastic, operatorial approach is used. Some properties of the linear stochastic systems, such as stability, stabilizability and detectability, are also discussed on the basis of a new solution representation result. A generalized Ito's formula which applies to infinite dimensional stochastic differential equations with countably infinite Markov jumps is also provided. 相似文献