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Degree reduced

The initiation of thermal decomposition of the polymer begins with the oxygen-containing groups that are contained in the structure of the molecular chains and are "weak bridges, " to a considerable degree reducing the thermal stability of the rubbers. [Pg.325]

This work considers the process of modification of the Indian rubber in the form of latex with ozone. Kinetics of the process has been studied. The proposed process proved to make it possible obtaining of a polymer comprised of the terminal carbonyl and carboxyl groups. It was found that an increase of ozonization degree reduced molecular mass of the Indian rubber. Main physical and mechanical properties of the rubber compounds based on the mixture of original and ozonizated mbbers were determined. Some advantages of the rubber compounds on the basis of the ozonized polymer were discussed in this chapter. [Pg.158]

Therefore, polymer permeabUity P, density, and mass fraction in the edges are the key parameters for this property. Bhatt et al. [31,39] suggested that increasing the crosshnking degree reduces the gas loss during mechanical testing, which is probably due to a reduction in polymer permeabihty. [Pg.116]

Earthquakes cause damage and contamination to water reticulation systems and to food supplies in people s homes, retail and wholesale food facilities, as well as food processing plants. Transport routes, including road, rail, water-based, and airport infrastructure into the affected areas, will be damaged to varying degrees, reducing supplies for at least days and often weeks or months. [Pg.973]

It also should be noted in Fig. 4.4high concentration, then this reduces the loss of valuable raw materials in the... [Pg.240]

Short-term exposure. This is the maximum concentration to which workers can be exposed for a period of up to 15 minutes continuously without suffering from (a) intolerable irritation, (b) chronic or irreversible tissue change, or (c) narcosis of sufficient degree to increase accident proneness, impair self-rescue, or materially reduce efficiency, provided that no more than four excursions per day are permitted, with at least 60 minutes between exposure periods, and provided the daily time-weighted value is not exceeded. [Pg.260]

Although a diatomic molecule can produce only one vibration, this number increases with the number of atoms making up the molecule. For a molecule of N atoms, 3N-6 vibrations are possible. That corresponds to 3N degrees of freedom from which are subtracted 3 translational movements and 3 rotational movements for the overall molecule for which the energy is not quantified and corresponds to thermal energy. In reality, this number is most often reduced because of symmetry. Additionally, for a vibration to be active in the infrared, it must be accompanied by a variation in the molecule s dipole moment. [Pg.57]

During the past few years radioscopy has established itself in many fields that demand instant evaluation and a high degree of automation, as is the case in serial inspection. Furthermore, user experience has clearly shown that inspection costs can be considerably reduced by this technique. [Pg.435]

Infrared Spectroscopy. The infrared spectroscopy of adsorbates has been studied for many years, especially for chemisorbed species (see Section XVIII-2C). In the case of physisorption, where the molecule remains intact, one is interested in how the molecular symmetry is altered on adsorption. Perhaps the conceptually simplest case is that of H2 on NaCl(lOO). Being homo-polar, Ha by itself has no allowed vibrational absorption (except for some weak collision-induced transitions) but when adsorbed, the reduced symmetry allows a vibrational spectrum to be observed. Fig. XVII-16 shows the infrared spectrum at 30 K for various degrees of monolayer coverage [96] (the adsorption is Langmuirian with half-coverage at about 10 atm). The bands labeled sf are for transitions of H2 on a smooth face and are from the 7 = 0 and J = 1 rotational states Q /fR) is assigned as a combination band. The bands labeled... [Pg.634]

Although in principle the microscopic Hamiltonian contains the infonnation necessary to describe the phase separation kinetics, in practice the large number of degrees of freedom in the system makes it necessary to construct a reduced description. Generally, a subset of slowly varying macrovariables, such as the hydrodynamic modes, is a usefiil starting point. The equation of motion of the macrovariables can, in principle, be derived from the microscopic... [Pg.735]

Often a degree of freedom moves very slowly for example, a heavy-atom coordinate. In that case, a plausible approach is to use a sudden approximation, i.e. fix that coordinate and do reduced dimensionality quantum-dynamics simulations on the remaining coordinates. A connnon application of this teclmique, in a three-dimensional case, is to fix the angle of approach to the target [120. 121] (see figure B3.4.14). [Pg.2311]

In light of oxidative processes, the high degree of resonance stabilization that arises from the maximally occupied HOMO (10 electrons), makes it an extremely difficult task to remove an electron from the HOMO level [31], Thus, [60]fullerene can be considered mostly an electronegative entity which is much more easily reduced than oxidized. [Pg.2413]

Explicit forms of the coefficients Tt and A depend on the coordinate system employed, the level of approximation applied, and so on. They can be chosen, for example, such that a part of the coupling with other degrees of freedom (typically stretching vibrations) is accounted for. In the space-fixed coordinate system at the infinitesimal bending vibrations, Tt + 7 reduces to the kinetic energy operator of a two-dimensional (2D) isotropic haiinonic oscillator. [Pg.480]

However, in many applications the essential space cannot be reduced to only one degree of freedom, and the statistics of the force fluctuation or of the spatial distribution may appear to be too poor to allow for an accurate determination of a multidimensional potential of mean force. An example is the potential of mean force between two ions in aqueous solution the momentaneous forces are two orders of magnitude larger than their average which means that an error of 1% in the average requires a simulation length of 10 times the correlation time of the fluctuating force. This is in practice prohibitive. The errors do not result from incorrect force fields, but they are of a statistical nature even an exact force field would not suffice. [Pg.22]

Increasing the fuzziness of object description reduces the number of descriptors used and broadens the scope of a similarity search. At the same time, increasing fuzziness may reduce the discriminatory power of desaiptors to unacceptable levels. Therefore it is desirable to be able to control the degree of fuzziness of desaiptors. [Pg.311]


See other pages where Degree reduced is mentioned: [Pg.343]    [Pg.456]    [Pg.930]    [Pg.982]    [Pg.456]    [Pg.75]    [Pg.96]    [Pg.470]    [Pg.63]    [Pg.115]    [Pg.12]    [Pg.331]    [Pg.20]    [Pg.520]    [Pg.343]    [Pg.456]    [Pg.930]    [Pg.982]    [Pg.456]    [Pg.75]    [Pg.96]    [Pg.470]    [Pg.63]    [Pg.115]    [Pg.12]    [Pg.331]    [Pg.20]    [Pg.520]    [Pg.780]    [Pg.176]    [Pg.614]    [Pg.735]    [Pg.255]    [Pg.501]    [Pg.1838]    [Pg.2048]    [Pg.2212]    [Pg.220]    [Pg.480]    [Pg.507]    [Pg.270]    [Pg.3]    [Pg.5]    [Pg.15]    [Pg.132]    [Pg.299]    [Pg.318]    [Pg.367]    [Pg.356]    [Pg.386]   
See also in sourсe #XX -- [ Pg.120 , Pg.203 ]




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