Search results for " MoM"
showing 10 items of 2281 documents
1H NMR study of dynamical inequivalence of cations in [C(NH2)3]3Sb2Cl9
2001
Abstract The proton NMR second moment and spin–lattice relaxation time have been studied for polycrystalline tris-guanidinium nonachlorodiantimonate(III) in a wide temperature range. The C 3 reorientation of two types of the cations, hindered by very different potential barriers (20.5 and 54.5 kJ/mol) has been revealed. An unusually large dynamical inequivalence of two cations evidently reflects their different crystalline environments.
¿La vuelta a los dos demonios? Cine y pasado reciente en Argentina: una lectura actual / The Return to the theory of two demons? Cinema and Recent Pa…
2016
Este artículo indaga acerca de los tres “momentos de la memoria” (Zarco, 2016: 12-13), entendiendo con ello, el espacio, la puesta en agenda, la visibilidad, los límites y los alcances que los diferentes gobiernos han otorgado a la reconstrucción del pasado reciente argentino. Dependiendo de la estrategia memorística propuesta por cada gobierno, el cine tendrá mayor o menor apoyo estatal, implicando ello una mayor o menor repercusión de público. Para abordar las políticas de la memoria del actual gobierno argentino, se indaga acerca de lo que hemos denominado el cuarto momento de la memoria, “Vuelta a los dos demonios (2016-)” en el que se evidencia un regreso a la “teoría de los dos demoni…
Magnetization and61Ni Mössbauer effect study of the ternary arsenide CrNiAs
2008
The results of x-ray diffraction, dc magnetization, and 61Ni M?ssbauer spectroscopy studies of the ternary arsenide CrNiAs are reported. This compound crystallizes in the orthorhombic Fe2P-type structure (space group ) with the lattice parameters a = 6.1128(2)?? and c = 3.6585(1)??. CrNiAs is a mean-field ferromagnet with Curie temperature TC = 171.9(1)?K and the critical exponents ? = 0.514(18), ? = 1.010(16), and ? = 2.922(10). The temperature dependence of the magnetic susceptibility above TC follows the modified Curie?Weiss law with a paramagnetic Curie temperature of 176.0(3)?K and effective magnetic moment per transition metal atom of 2.42(1)??B. The magnetic moment per formula unit a…
Geometric, electronic, and magnetic structure ofCo2FeSi: Curie temperature and magnetic moment measurements and calculations
2005
In this work a simple concept was used for a systematic search for materials with high spin polarization. It is based on two semiempirical models. First, the Slater-Pauling rule was used for estimation of the magnetic moment. This model is well supported by electronic structure calculations. The second model was found particularly for ${\mathrm{Co}}_{2}$ based Heusler compounds when comparing their magnetic properties. It turned out that these compounds exhibit seemingly a linear dependence of the Curie temperature as function of the magnetic moment. Stimulated by these models, ${\mathrm{Co}}_{2}\mathrm{FeSi}$ was revisited. The compound was investigated in detail concerning its geometrical…
3D-simulation studies of the modified magnetic multipole structure for an electron cyclotron resonance ion source
2004
Experiments have shown that efficient operation of an electron cyclotron resonance ion source requires that the magnetic field fulfills the so-called scaling laws. In most cases the requirements for the radial magnetic field, i.e. the strength of the magnetic multipole are the most difficult to satisfy. This is due to the fact that the multipole is usually produced from permanent magnets, which makes a value of 1.3 T feasible. One possible solution to increase the multipole field is the so-called Modified MultiPole Structure (JYFL-MMPS). This new idea makes it possible to increase the magnetic field at the places where the plasma flux is in contact with the plasma chamber wall. In this arti…
Użycie słowa „czas” w Księdze Syracydesa
2020
Artykuł ma na celu przedstawienie użycia słowa „czas” w Księdze Syracydesa. W tym celu autor syntetycznie ukazał najpierw pole semantyczne terminu „czas” w języku hebrajskim i greckim. Następnie, na podstawie wskazanych rozróżnień, zostały przedstawione fragmenty, w których pojawia się omawiany termin, z uwzględnieniem kontekstu całej księgi, jak i pozostałych ksiąg biblijnych. Dla mędrca z Jerozolimy czas nie jest jedynie pojęciem wyznaczającym chronologię, ale rzeczywistością, którą codziennie człowiek odkrywa jako sposobność do czynienia dobra i przestrzeń działania Boga jako Stwórcy i Pana całego stworzonego świata. Różnorodność sytuacji życiowych, które przedstawia Ben Syrach w swej ks…
Measurement of dijet production with a veto on additional central jet activity in pp collisions at sqrt(s)=7 TeV using the ATLAS detector
2011
A measurement of jet activity in the rapidity interval bounded by a dijet system is presented. Events are vetoed if a jet with transverse momentum greater than 20 GeV is found between the two boundary jets. The fraction of dijet events that survive the jet veto is presented for boundary jets that are separated by up to six units of rapidity and with mean transverse momentum 50 < p¯T < 500 GeV. The mean multiplicity of jets above the veto scale in the rapidity interval bounded by the dijet system is also presented as an alternative method for quantifying perturbative QCD emission. The data are compared to a next-to-leading order plus parton shower prediction from the powheg-box, an all-order…
Exchange-transfer in mixed-valence clusters with one migrating hole
1996
Abstract A new mechanism for exchange-transfer specific to hole-type mixed-valence clusters is proposed. The intermediate state in the second-order exchange-transfer process is achieved by the jump of the electron from the spin-core of the dn+1 ion into the empty orbital of the dn ion. As distinguished from the mixed-valence clusters with one delocalized electron this intermediate state is the high-spin one giving rise to a ferromagnetic contribution to the ground manifold. On the basis of angular momentum theory a general solution of the exchange-transfer problem is given for arbitrary nuclearity mixed-valence hole-type clusters with many-electron paramagnetic spin-cores. The interplay bet…
General restrictions for the relaxation constants of the polarization moments of the density matrix
1992
General inequalities for the relaxation constants of polarization moments are examined. Concrete numerical limitations for the values of these constants are obtained. In recent years it has been generally accepted to characterize the distribution of the angular momentum j of atomic as well as molecular states in the framework of the irreducible tensorial operators PG. The state is described by means of polarization moments p& which are the expansion coefficients of the angular momentum density matrix pm,,,, on the tensorial operators pz:
Perturbative treatment of triple excitations in coupled‐cluster calculations of nuclear magnetic shielding constants
1996
A theory for the calculation of nuclear magnetic shielding constants at the coupled‐cluster singles and doubles level augmented by a perturbative correction for connected triple excitations (CCSD(T)) has been developed and implemented. The approach, which is based on the gauge‐including atomic orbital (GIAO) ansatz, is illustrated by several numerical examples. These include a comparison of CCSD(T) and other highly correlated methods with full configuration interaction for the BH molecule, and a systematic comparison with experiment for HF, H2O,NH3, CH4, N2, CO, HCN, and F2. The results demonstrate the importance of triple excitations in establishing quantitative accuracy. Finally, the abil…