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Picture restoration

A higher standard of reversibility was that demanded by picture restorers in Berlin in the 1840s that the treatment when reversed should not affect subsequent treatments (Mure, 1853). This is one of the necessary requirements for a facing technique on paintings. [Pg.22]

Caley, T. (1998). A note on the reversal of BEVA Unings. The Picture Restorer, 14, 14. [Pg.147]

Makin, S. (1997). Miniatures and their conservation. The Picture Restorer (12), 8-10. [Pg.165]

Szmit-Naud, E. (2003). Research on materials for easel painting retouches Part 2. The Picture Restorer (24), 5-9. [Pg.166]

Prunet-Brewer, T., Routledge, V. (2001). Retouching with MS2A another approach. The Picture Restorer (20), 15-16. [Pg.217]

Lead(II) sulphide is oxidised to lead(II) sulphate this reaction has been used in the restoration of old pictures where the white lead pigment has become blackened by conversion to lead sulphide due to hydrogen sulphide in urban air ... [Pg.280]

The requirement I > 2 can be understood from the symmetry considerations. The case of no restoring force, 1=1, corresponds to a domain translation. Within our picture, this mode corresponds to the tunneling transition itself. The translation of the defects center of mass violates momentum conservation and thus must be accompanied by absorbing a phonon. Such resonant processes couple linearly to the lattice strain and contribute the most to the phonon absorption at the low temperatures, dominated by one-phonon processes. On the other hand, I = 0 corresponds to a uniform dilation of the shell. This mode is formally related to the domain growth at T>Tg and is described by the theory in Xia and Wolynes [ 1 ]. It is thus possible, in principle, to interpret our formalism as a multipole expansion of the interaction of the domain with the rest of the sample. Harmonics with I > 2 correspond to pure shape modulations of the membrane. [Pg.149]

The production of DA from levodopa should restore the normal striatal picture from that proposed for PD by inhibiting striatal output pathways (Fig. 15.8). It may... [Pg.312]

Ordinarily, when the current pulse is over, the excess charges will be drained through the passive transport channels, and by operation of the sodium-potassium pumps the original values of membrane potential and of the concentration gradients will be reestablished. However, when in the case of depolarization the negative value of cp has dropped below a certain threshold value, which is about -50 mV, the picture changes drastically Excitation of the membrane occurs. When the current is turned off, the membrane potential not only fails to be restored but continues to... [Pg.580]

In summary, the chain dynamics for short times, where entanglement effects do not yet play a role, are excellently described by the picture of Langevin dynamics with entropic restoring forces. The Rouse model quantitatively describes (1) the Q-dependence of the characteristic relaxation rate, (2) the spectral form of both the self- and the pair correlation, and (3) it establishes the correct relation to the macroscopic viscosity. [Pg.22]

To be suitable for use in museum preservation and restoration practice, picture varnishes must have a number of defined characteristics (a) they must not interact with the object in a detri-... [Pg.183]

Giant dipole resonance. Isovector giant resonances contain information about the SE through the restoring force. In particular the excitation of the isovector giant dipole resonance (GDR) with isoscalar probes has been used to extract A R/R [32], In the distorted wave Bom approximation optical model analysis of the cross section the neutron and proton transition densities are needed as an input. For example, in the Goldhaber-Teller picture these are... [Pg.107]

According to this picture, it is possible to restore the notion of a mechanistic spectrum of ET and Sfg2 processes that the sole consideration of energetic factors did not permit. Within this framework, there is no real difference between the notions of comptetition between the two mechanisms... [Pg.109]

These solid phases are connected to the components in Fig. 4, with which they are in reversible equilibrium. For example, if magnesium ion were added to a complex solution containing solid calcium oxalate monohydrate (COM), the magnesium would compete with calcium for an increased share of the oxalate this would reduce the amount of the calcium oxalate complex, and finally a small amount of calcium oxalate sohd would dissolve to restore the complex concentration to its equilibrium value. In urine, this picture must be extended to account for the molecular substances that coat crystals and reduce access of the solution to the surface coated crystals do not redissolve readily. [Pg.91]

Nonlinear optical effects can be introduced into this picture by postulating that the restoring force in equation 1 is no longer linear in the displacement and adding a term, say ar2, to the left hand side of the equation, (3). The differential equation can no longer be solved in a simple way but, if the correction term is assumed to be small relative to the linear term, a straightforward solution follows leading to a modification of equation 3. [Pg.39]

If restoration or preservation is required, a professional is consulted to slow the deterioration, thus giving the work an extended life. With some works of art, this is difficult. Many modem works are made of materials that are difficult to preserve and restore, such as newspaper, poor-quality paint, and experimental materials that may be glued to the surface or mixed with the paint. Many pictures are painted on a poorly prepared surface using very heavy applications of paint in time, the paint will begin to fall off the canvas or other working surface. It is the task of the restorer to do whatever is possible to preserve as much of the work as possible. [Pg.345]

The picture of a chemical reaction as the passage from the reactant to the product energy well implies the existence of the M.I.R., but some assumption is required about the shape of the wells in order to obtain an analytical formulation of the rate constant. The simplest case is that of harmonic energy wells, based on Hooke s law which relates the restoring force F linearly to the displacement Ax,... [Pg.100]

Second order corrections to the energy of sp3 carbon atom. In order to construct the required mechanistic picture, the estimate of the restoring force which opposes both the quasi- and pseudorotation (deformation) of the hybridization tetrahedra is necessary. That can be obtained by a linear response procedure. For the sp3 carbon atom in the symmetric tetrahedral environment, the related resonance energy is a diagonal quadratic form with respect to small quasi- and pseudorotations together with triply degenerate eigenvalues [44,45] ... [Pg.242]

Knowing the structure of a complex machine and knowing how it works are two different matters. One could open the hood of a car and take pictures of the motor until the cows come home, but the snapshots by themselves would not give a clear idea of how the different parts produced the function. Ultimately, in order to find out how a thing works, you have to take it apart and reassemble it, stopping at many points to see if function has yet been restored. Even this may not... [Pg.62]


See other pages where Picture restoration is mentioned: [Pg.54]    [Pg.54]    [Pg.522]    [Pg.562]    [Pg.61]    [Pg.195]    [Pg.538]    [Pg.429]    [Pg.465]    [Pg.118]    [Pg.34]    [Pg.24]    [Pg.31]    [Pg.422]    [Pg.233]    [Pg.48]    [Pg.2]    [Pg.131]    [Pg.79]    [Pg.619]    [Pg.263]    [Pg.523]    [Pg.420]    [Pg.38]    [Pg.130]    [Pg.280]    [Pg.178]    [Pg.309]    [Pg.544]    [Pg.87]   
See also in sourсe #XX -- [ Pg.7 ]




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Restoration

Restorative

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