scholarly journals Impurity-induced and Second Order Raman Spectra of NaCl Crystals Doped with Different Ag+ Concentrations

1970 ◽  
Vol 25 (7) ◽  
pp. 1024-1029 ◽  
Author(s):  
W. Möller ◽  
R. Kaiser

Raman spectra of NaCl crystals doped with Ag+ ions up to 3.5 mol% have been measured in 4 scattering geometries. In the impurity induced part of the Eg- and F2g-spectra the strongest peaks are located at 85 and 171 cm-1. Their intensities increase proportional to the silver concentration. The second order Raman spectrum on the other hand appears to be independent of the Ag+ content. The spectra are fully explained by theory and by the assumption of Ag+ pairs

1993 ◽  
Vol 19 (1) ◽  
Author(s):  
S. M. Van Vuuren ◽  
M. Schepers

The construction and evaluation of a job satisfaction inventory for ministers. Job satisfaction is a multidimensional construct indicating the degree of adjustment of a worker to his work. A questionnaire was constructed for measuring the various aspects of job satisfaction of ministers. It was administered to 307 ministers. First and second order factor analyses were performed on the items of the questionnaire. Three strong factors of the job satisfaction of ministers were identified, viz. satisfaction with the work as such, the minister's experience of the relationships between him and his wife on the one hand, and his church council and congregation on the other hand, and his vocational self concept. The implications of these findings are discussed. Opsomming Werkstevredenheid is 'n meerdimensionele konstruk wat 'n aanduiding gee van die mate waarin 'n werker in sy werk aanpas. 'n Vraelys om verskeie aspekte van die werkstevredenheid van predikante te meet, is gekonstrueer. Dit is op 'n steekproef van 307 predikante toegepas. Eerste- en tweedeorde-faktorontledings is op die items van die vraelys uitgevoer. Drie sterk faktore van die werkstevredenheid van predikante is geidentifiseer, te wete die belewing van sy werk as sodanig, die belewing van die verhouding tussen horn en sy vrou aan die een kant, en die kerkraad en gemeente aan die ander kant, en sy beroepselfkonsep. Die implikasies van die bevindinge word bespreek.


2015 ◽  
Vol 5 (6) ◽  
pp. 115
Author(s):  
Lei Qiu

<p>Along with the general trends of research from traditional Gricean approach to postmodern approach, politeness has been conceptualized as facework, social indexing concept, relational work and interactional work. Based on examination of debates over East group-oriented and Western individual-oriented politeness, first-order and second-order politeness, as well as the universality and relativity of conceptualizations, this paper has roughly demonstrated that the tension between universality and relativity of politeness can help to explain the reason for lack of uniform definition and concept in this field. It is essential for researchers to seek a universal second-order culture-general theoretical construct on one hand, and to look at first-order culture-specific constructs on the other hand.</p>


A wave equation is given which, in the force-free case, describes a particle of unique spin and mass and which remains consistent when interactions are included. The equation is simple in the sense that it involves only matrices which satisfy the Pauli commutation rules. This simplicity is achieved at the expense of extending the particle field vector from one of 2j + 1 components to one of 4j. However, the extra 2j — 1 components are just what are needed to remove the inconsistency of the interacting system. In the force-free case these additional components vanish and the resulting equations are equivalent to the usual ones of Dirac, Fierz and Pauli. One the other hand, for the interacting system, the extra components do not vanish. The second order propagation equations are deduced in the case of external electromagnetic and gravitational fields.


1974 ◽  
Vol 52 (10) ◽  
pp. 2207-2218 ◽  
Author(s):  
A. Silvy

In Lycopersicum esculentum Mill, and L. pimpinellifolium Dun. ramification modes of plants with determinate and indeterminate habits are studied by macroscopic observation (apex evolution, phyllotaxis, and leaf number of the different branches of a mature plant) and also by analyzing mutated sectors after seed treatment. While the first inflorescence, a cyme, originates from the greater part of the prefloral apex, the top of which bears the first flower, second-order axes come up at the axils of the last two leaves. In all the varieties, the axillary bud of the second-last leaf produces a sympodial lateral ramification. On the other hand, that of the last leaf, which becomes visible on the side of the prefloral apex, as anticipated, immediately bears a second inflorescence in varieties with determinate habit, but makes up the second-order axis of the main sympodium in varieties with indeterminate habit. The characteristics of these two bud patterns are compared.


2005 ◽  
Vol 13 (S2) ◽  
pp. 3-11 ◽  
Author(s):  
KUNO LORENZ

The concept of symmetry is omnipresent, although originally, in Greek antiquity, distinctly different from the modern logical notion. In logic a binary relation R is called symmetric if xRy implies yRx. In Greek, ‘being symmetric’ in general usage is synonymous with ‘being harmonious’, and in technical usage, as in Euclid's Elements, it is synonymous with ‘commensurable’. Due to the second meaning, which is close to the etymology of συ´μμετρoς, ‘with measure’ has likewise to be read as ‘being [in] rational [ratios]’ and displays the origin of the concept of rationality of establishing a proportion. Heraclitus can be read as a master of such connections. Exercising rationality is a case of simultaneously finding and inventing symmetries. On that basis a proposal is made of how to relate the modern logical notion of symmetry, a second-order concept, on the one hand with modern first-order usages of the term symmetric in geometry and other fields, and on the other hand with the notion of balance that derives from the ancient usage of symmetric. It is argued that symmetries as states of balance exist only in theory, in practice they function as norms vis-à-vis broken symmetries.


Author(s):  
Jan Dereziński ◽  
Vladimir Georgescu

AbstractWe consider the Schrödinger operator on the halfline with the potential $$(m^2-\frac{1}{4})\frac{1}{x^2}$$ ( m 2 - 1 4 ) 1 x 2 , often called the Bessel operator. We assume that m is complex. We study the domains of various closed homogeneous realizations of the Bessel operator. In particular, we prove that the domain of its minimal realization for $$|\mathrm{Re}(m)|<1$$ | Re ( m ) | < 1 and of its unique closed realization for $$\mathrm{Re}(m)>1$$ Re ( m ) > 1 coincide with the minimal second-order Sobolev space. On the other hand, if $$\mathrm{Re}(m)=1$$ Re ( m ) = 1 the minimal second-order Sobolev space is a subspace of infinite codimension of the domain of the unique closed Bessel operator. The properties of Bessel operators are compared with the properties of the corresponding bilinear forms.


1982 ◽  
Vol 47 (1) ◽  
pp. 131-136 ◽  
Author(s):  
Marcel Crabbé

NFP is the predicative fragment of NF. In this system we do not allow a set to exist if it cannot be defined without using quantifiers ranging over its type or parameters of a higher type. NFI is a less restrictive fragment located between NFP and NF.We show that NFP is really weaker than NFI; similarly, NFI is weaker than NF. This result will be obtained in the following manner: on the one hand, we will show that NFP can be proved consistent in elementary arithmetic and that second order arithmetic is interpretable in NFI; on the other hand, we will prove the consistency of NFI in third order arithmetic, which is contained in NF.The paper is divided in four sections. In §1, we define the concepts needed and collect a few results together in such a way that they will be ready for later use. In §2, we will present a model-theoretic (quick) proof of the consistency of NFI (and thus of NFP). The proof will be chosen (it is not the quickest!) so as to motivate in a natural manner the details of the proof-theoretical version of it that will be presented in §3. §4 will be devoted to the axiom of infinity in NFP and NFI.


2020 ◽  
Vol 641 ◽  
pp. A48
Author(s):  
J. L. Ballester ◽  
R. Soler ◽  
J. Terradas ◽  
M. Carbonell

Context. Partially ionized plasmas constitute an essential ingredient of the solar atmosphere since layers such as the chromosphere and the photosphere and structures such as prominences and spicules are made of this plasma. On the other hand, ground- and space-based observations have indicated the presence of oscillations in partially ionized layers and structures of the solar atmosphere, which have been interpreted in terms of magnetohydrodynamic (MHD) waves. Aims. Our aim is to study the temporal behavior of nonlinear Alfvén waves, and the subsequent excitation of field-aligned motions and perturbations, in a partially ionized plasma when dissipative mechanisms such as ambipolar diffusion, radiative losses, and thermal conduction are taken into account. Methods. First, we applied the regular perturbations method for small-amplitude initial perturbations to obtain the temporal behavior of perturbations. Then we solved the full set of nonlinear MHD equations for larger values of the initial amplitude. Results. We obtain analytical and numerical solutions to first-, second-, and third-order systems of equations and study the effects produced by ambipolar diffusion and thermal mechanisms on the temporal behavior of Alfvén and slow waves. We also study how the majority of the energy is transferred from the Alfvén waves to plasma internal energy. After numerically solving the full nonlinear equations when a large amplitude is assumed, the profile of the perturbations displays the typical sawtooth profile characteristic of associated shocks. Conclusions. When ambipolar diffusion is taken into account, first-order Alfvén waves are damped in time, while second-order perturbations are undamped. However, due to the release of heat produced by ambipolar diffusion, other physical effects that modify the physical conditions in the spatial domain under consideration appear. On the other hand, the second-order perturbations are damped by thermal effects with a damping time that can be longer or shorter than that of Afvén waves. Therefore, after the initial excitation, Alfvén waves can be quickly damped, while slow waves remain in the plasma for a longer time, and vice versa.


2011 ◽  
Vol 20 (05) ◽  
pp. 1171-1182 ◽  
Author(s):  
DIPAK GHOSH ◽  
ARGHA DEB ◽  
SWARNAPRATIM BHATTACHARYYA ◽  
UTPAL DATTA

In this paper we have studied the multiplicity distribution of black and grey particles emitted from 16 O – AgBr interactions at 2.1 AGeV and 60 AGeV. We have also calculated the multiplicity moment up to the fifth order for both the interactions and for both kinds of emitted particles. The variation of multiplicity moment with the order number has been investigated. It is seen that in the case of black particles multiplicity moment up to fourth order remains almost constant as energy increases from 2.1 AGeV to 60 AGeV. Fifth order multiplicity moment increases insignificantly with energy. However in the case of grey particles no such constancy of multiplicity moment with energy of the projectile beam is obtained. Later we have extended our study on the basis of Regge–Mueller approach to find the existence of second order correlation during the emission of black as well as the grey particles. The second Mueller moment is found to be positive and it increases as energy increases in the case of black particles. On the contrary in the case of grey particles the second Mueller moment decreases with energy. It can be concluded that as energy increases correlation among the black particles increases. On the other hand with the increase of energy correlation among the grey particles is found to diminish.


1911 ◽  
Vol 30 ◽  
pp. 31-36
Author(s):  
D. M. Y. Sommerville

One of the most plausible of the host of “proofs” that have ever been offered for Euclid's parallel-postulate is that known as Bertrand's, which is based upon a consideration of infinite areas. The area of the whole plane being regarded as an infinity of the second order, the area of a strip of plane surface bounded by a linear segment AB and the rays AA′, BB perpendicular to AB is an infinity of the first order, since a single infinity of such strips is required to cover the plane. On the other hand, the area contained between two intersecting straight lines is an infinity of the same order as the plane, since the plane can be covered by a finite number of such sectors. Hence if AP is drawn making any angle, however small, with AA′, the area A′AP, an infinity of the second order, cannot be contained within the area A′ABB′, an infinity of the first order, and therefore AP must cut BB′. And this is just Euclid's postulate.


Sign in / Sign up

Export Citation Format

Share Document