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71.
72.
W. M. Seif 《The European Physical Journal A - Hadrons and Nuclei》2008,38(1):85-95
To probe the nuclear equation of state, several fusion cross-sections have been analyzed using microscopic nucleus-nucleus
potentials calculated in the framework of the Hamiltonian energy density approach through the well-known Skyrme nucleon-nucleon
effective interaction with eighteen different parameterizations which express various equations of state. Three density-dependent
M3Y-Paris effective forces are examined also within the double-folding model. The various effective forces give incompressibility
modulus values which vary over a rather wide range between 188MeV and 372MeV. The extracted fusion barrier distributions are
examined too with the same aim. The most successfully investigated interactions in deriving satisfactory fusion excitation
functions as well as barrier distributions are those giving equations of state with nuclear incompressibility values in the
range of 230-241MeV, according to the isospin asymmetry of the interacting nuclei. 相似文献
73.
Al Lafi Abdul G. Al Abdullah Jamal Amin Yusr Alnama Tasneem Aljbai Yara Hasan Reem Alsayes Ghina 《Journal of Radioanalytical and Nuclear Chemistry》2019,321(2):463-472
Various composite adsorbents based on sulfonated poly(ether ether ketone)/manganese dioxide were prepared for the removal of stable and radioactive ions from contaminated aqueous solution. Batch adsorption experiments revealed superior adsorption capacities of the composite using very low initial concentration of studied elements. Starting with 1000 µg L−1 contaminated solution, the maximum equilibrium metal uptake capacity reached 2.0 mg g−1 for Pb2+, 1.9 mg g−1 for Cd2+, Cu2+ and Zn2+, and 3.7 mg g−1 for Co2+. In addition, the distribution coefficient reached 11,600 mL g−1 for 137Cs and 70,000 mL g−1 for 210Pb.
相似文献74.
I. Borbély-Kiss M. Józsa Á. Z. Kiss E. Koltay B. Nyakó E. Somorjai Gy. Szabó S. Seif El-Nasr 《Journal of Radioanalytical and Nuclear Chemistry》1985,92(2):391-398
It is demonstrated that combined PIXE and PIGE measurements are suitable for the accurate determination of the elemental concentration of glass samples. Borosilicate glasses used as high voltage insulators in Van de Graaff accelerators and tested for the relevant physical properties have been analyzed. A correlation between concentrations and physical properties has been found, supporting the additivity rule. 相似文献
75.
I. Borbély-Kiss E. Koltay S. László Gy. Szabó S. Gödény S. Seif El-Nars 《Journal of Radioanalytical and Nuclear Chemistry》1984,83(1):175-185
Elemental concentrations of P, S, Cl, K, Ca, Fe, Ni, Cu, Zn, Br, Rb have been determined in erythrocyte and blood plasma samples from normal and diabetic human pregnancies. Average values, the dependence of the concentrations on the time during gestation period, the correlation coefficients for pairs of elements as well as for the same elements in plasma and erythrocyte samples are given. A marked difference appeared in a number of cases between normal and diabetic pregancies. 相似文献
76.
Our efforts toward the development of the synthesis of a novel type of receptor ligand and its tetrasubstituted phthalocyanines, 2,9,16,23-tetrakis(6-hydroxyhexylsulfanyl) phthalocyanine, M[Pc(S–C6H13OH)4] (M = Zn(II), Cu(II), Co(II)), bearing sulfur and oxygen donor atoms on the periphery together with hexyl moieties, have been carried out together with spectroscopic and electrochemical characterization. The newly synthesized functional phthalocyanines were soluble in MeOH, EtOH, THF, DMF, CNP (α-chloronapthalene), DMSO and quinoline, and less soluble in i-PrOH and CH3CN. Cation binding abilities of the functional phthalocyanines with Ag+, Pd2+, Hg2+ and Cd2+, resulting in the formation of polynuclear phthalocyanine complexes, were evaluated by UV–Vis spectroscopic techniques. The spectroscopic properties of the complexes were affected strongly by the electron-donating sulfanyl units on the periphery. The cyclic voltammetry of the complexes were examined on a platinum electrode in DMSO. The new synthesized compounds have been characterized by elemental analysis, FTIR, 1H and 13C NMR, MS (ESI and MALDI-TOF) and UV–Vis spectral data. 相似文献
77.
S. W. Seif 《Proceedings of the American Mathematical Society》1996,124(5):1361-1370
For an arbitrary algebra a new labelling, called the signed labelling, of the Hasse diagram of is described. Under the signed labelling, each edge of the Hasse diagram of receives a label from the set . The signed labelling depends completely on a subset of the unary polynomials of and its inspiration comes from semigroup theory. For finite algebras, the signed labelling complements the labelled congruence lattices of tame congruence theory (TCT). It provides a different kind of information about those algebras than the TCT labelling particularly with regard to congruence semimodularity. The main result of this paper shows that the congruence lattice of any algebra admits a natural join congruence, denoted , such that satisfies the semimodular law. In an application of that result, it is shown that for a regular semigroup , for which in , is actually a lattice congruence, coincides with , and satisfies the semimodular law.
78.
For a word w in an alphabet Γ, the alternation word digraph Alt(w), a certain directed acyclic graph associated with w, is presented as a means to analyze the free spectrum of the Perkins monoid \(\mathbf{B_2^1}\). Let \((f_n^{\mathbf{B_2^1}})\) denote the free spectrum of \(\mathbf{B_2^1}\), let a n be the number of distinct alternation word digraphs on words whose alphabet is contained in {x 1,..., x n }, and let p n denote the number of distinct labeled posets on {1,..., n}. The word problem for the Perkins semigroup \(\mathbf{B_2^1}\) is solved here in terms of alternation word digraphs: Roughly speaking, two words u and v are equivalent over \(\mathbf{B_2^1}\) if and only if certain alternation graphs associated with u and v are equal. This solution provides the main application, the bounds: \(p_n \leq a_n \leq f_n^{\mathbf{B_2^1}} \leq 2^{n}a_{2n}^2\). A result of the second author in a companion paper states that \((\operatorname{log} \; a_n)\in O(n^3)\), from which it follows that \((\operatorname{log} f_n^{\mathbf{B_2^1}})\in O(n^3)\) as well. Alternation word digraphs are of independent interest combinatorially. It is shown here that the computational complexity problem that has as instance {u,v} where u,v are words of finite length, and question “Is Alt(u)?=?Alt(v)?”, is co-NP-complete. Additionally, alternation word digraphs are acyclic, and certain of them are natural extensions of posets; each realizer of a finite poset determines an extension by an alternation word digraph. 相似文献
79.
Dr. Ayan Dasgupta Yara van Ingen Michael G. Guerzoni Dr. Kaveh Farshadfar Prof. Jeremy M. Rawson Dr. Emma Richards Prof. Alireza Ariafard Prof. Rebecca L. Melen 《Chemistry (Weinheim an der Bergstrasse, Germany)》2022,28(45):e202201422
An efficient and mild reaction protocol for the decarbonylation of isocyanates has been developed using catalytic amounts of Lewis acidic boranes. The electronic nature (electron withdrawing, electron neutral, and electron donating) and the position of the substituents (ortho/meta/para) bound to isocyanate controls the chain length and composition of the products formed in the reaction. Detailed DFT studies were undertaken to account for the formation of the mono/di-carboxamidation products and benzoxazolone compounds. 相似文献
80.
Gerami Alireza Alzahid Yara Mostaghimi Peyman Kashaninejad Navid Kazemifar Farzan Amirian Tammy Mosavat Nader Ebrahimi Warkiani Majid Armstrong Ryan T. 《Transport in Porous Media》2019,130(1):277-304
Transport in Porous Media - No matter how sophisticated the structures are and on what length scale the pore sizes are, fluid displacement in porous media can be visualized, captured, mimicked and... 相似文献