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Interference mechanisms

Plasticization has been explained by a variety of theories in an attempt to explain how the plasticizer reduces the rigidity of the final part. All theories rely on the premise that the plasticizer reduces the strength of the intermolecular forces between the polymer chains. The theories fall into two broad categories interference mechanisms and expansion mechanisms. The interference mechanisms state that plasticizer molecules interact only weakly with the polymer chains after separating the chains from one another, thereby reducing the overall cohesion of the material. The expansion mechanisms state that the reduced rigidity arises from an increase in the free volume of the system as the system expands to incorporate bulky,... [Pg.350]

L.W. Jones, "Interference Mechanism in Waste Solidification/ Stabilization Processes, EPA-600/S-89/067 (NTIS No. PB90-156209/AS), USEPA, Risk Reduction Engineering Laboratory, Cincinati, OH, 1989. [Pg.121]

ICP-AES was validated for the simultaneous determination of Al, B, Ba, Be, Cd, Co, Cr, Cu, Fe, Li, Mn, Ni, Pb, Se, Sr and Zn in human serum in a clinical laboratory. The samples underwent digestion and yttrium was used as an internal standard. The LOD were as follows 0.002-0.003 (xM for Ba, Cd, Mn and Sr 0.014-0.07 (xM for Be, Co, Cr, Cu, Fe, Li, Ni, Pb and Zn and 0.2-0.9 (xM for Al, B and Se. The concentrations of Al, Be and Co in human serum were found to be above the LOD, while those of Cd, Cr, Ni and Pb were below the LOQ however, in case of acute intoxication with the latter elements the method is valid . Matrix effects were evaluated for ICP-AES analysis using solution nebulization and laser ablation (LA) techniques. The main matrix-related interferences stem from elements with a low second ionization potential however, these are drastically reduced when pure He is used as carrier gas. This points to Ar (the usual carrier) participation in the interference mechanism, probably by interacting with doubly charged species. ... [Pg.325]

In this strong-field regime the bk t) coefficients are embedded in k(E) [see Eq. (13.58)] and are themselves functions of e(f). Hence the problem is inherently nonlinear, necessitating an iterative solution. Nevertheless, the same interference mechanism outlined in the wealc-field domain applies. The only difference is that the pulse-shaping conditions are given implicitly via Eq. (13.66), rather than explicitly via Eq. (13.64), as in the weak-field domain. [Pg.321]

A few insecticides interfere mechanically with the insect s functions. For example, mineral oils suffocate insects silica dusts destroy their body water balance by damaging their protective wax covering. [Pg.84]

The present study uses a quantum statistical method to show how the time-profile of CARS from molecules in liquids is associated with the inteimolecular dephasing mechanisms. Liouville space Feynman diagrams are used for the development of relevant transitions associated with pmrs of molecules. - The structure of the inteimolecular dephasing constant is clarified to identify the difference between the inteimolecular dephasing constant and intramolecular dephasing constant in Sec.ll. Section III presents the rovibrational interference mechanism. The sub-picosecond decay observed in CARS profile of neat benzene is explained in terms of this mechanism. [Pg.170]

Cholesteric reflectors for all wavelengths of the visible spectrum [26-29] will be used as reflectors and polarizers for back lights of LC displays to get a higher yield of the emitted light Classical dyes containing polarizers absorb 50% of the polarized light in contrast to the cholesteric systems based on a non-absorptive interference mechanism. [Pg.580]

Figure 5.36 RiNA interference mechanism. A double-stranded RNA molecule is cleaved into 21-bp fragments by the enzyme Dicer to produce siRNAs. These siRNAs are incorporated into the RNA-induced silencing complex (RISC), where the single-stranded RNAs guide the cleavage of mRNAs that contain complementary sequences. Figure 5.36 RiNA interference mechanism. A double-stranded RNA molecule is cleaved into 21-bp fragments by the enzyme Dicer to produce siRNAs. These siRNAs are incorporated into the RNA-induced silencing complex (RISC), where the single-stranded RNAs guide the cleavage of mRNAs that contain complementary sequences.
Interference Mechanisms in Waste Stabilization/Solidification Processes... [Pg.90]

Photometric and polarimetric data obtained from telescopic observations and laboratory measurements at small phase angles have been accnmnlating for many years however, the interpretation of these effects, especially of the polarization branch, was not satisfactory until recently [7-20] when the coherent backscattering (interference) mechanism was developed to explain both effects. Since that time, additional experimental [21-23] and theoretical [18, 24-28] data were obtained, showing that the effects are more complex than initially considered. For example, negative polarization branches with two minima were discovered for some Jupiter satellites and bright asteroids [29,30], and unusual behavior of the opposition spike amphtude with albedo for the Moon, asteroids, and Jupiter s satellite Europa were found [31-33]. [Pg.194]

A modehng effort has demonstrated that the polarization opposition effect can be reproduced using the enhanced backscatter mechanism, namely the constractive interference of reciprocal rays. Varions models have been developed that reprodnce this featnre. For instance, a vector theory of coherent backscattering for a semi-infinite medinm of Rayleigh scatterers is able to reproduce the stracture of the polarization featnre when the cyclical (reciprocal) terms are inclnded [8-12]. In addition, various ray-tracing methodologies from different types of scattering systems also are able to produce the features of the polarization opposition effect when the constmctive interference mechanism is inclnded [13-21]. Several review articles address this topic [2, 7, 12, 18]. [Pg.210]

Chemical Interferences. Chemical effects originate either in the flame or in the sample solution. The interference mechanisms may be divided into the two groups (i) The atomization of the analyte element is not completed either in the solid phase or in the liquid (condensed) phase (ii) The vaporized atoms react with other atoms or radicals present in the gas phase. [Pg.66]

Yamaguchi,T., Kiwa,T.,Tsukada, K. and Yokosawa, K. (2007), Oxygen interference mechanism of platinum-FET hydrogen gas sensor. Sensors and Actuators A, 136(1), 244-8. [Pg.158]

Xingzhi Hu, Jikun Wang. Frequency devices. Electromagnetic interference mechanism of coal mine safety monitoring system [J] Journal of North China Institute of Science and Technology, 2013 (1) 83-85. (in Chinese). [Pg.362]

Chemical interference must be distinguished from resource competition. The studies of Nilsson and colleagues in which PVC pipes were used to reduce belowground competition, and activated carbon was used to reduce allelopathy, illustrate one approach to this problem. Muller s application of manure to bare zones in the chaparral represents another. Demonstrating density-dependent inhibition of growth offers another means of distinguishing the operation of these interference mechanisms. The probability that allelopathy and resource competition together cause the observed inhibitory effects (Nilsson 1994) must be kept in mind. [Pg.203]

In addition to the already described interference mechanisms, we also consider the special properties of light matter interactions at a metal surface. The transition moment Vj can be expressed as a function of the vector potential operator A of the excitation field and the momentum operator p = — itiV. It has been shown that the dipole approximation has significant deficiencies in a quantitative description of the optical excitation of adsorbates, which require explicit accounting of the variation in the vector potential at the surface in the... [Pg.270]

Although the relative importance of the various interference mechanisms that are simultaneously at work in the case of the Cs o-resonance and the SS... [Pg.270]


See other pages where Interference mechanisms is mentioned: [Pg.379]    [Pg.160]    [Pg.175]    [Pg.18]    [Pg.617]    [Pg.352]    [Pg.432]    [Pg.540]    [Pg.188]    [Pg.72]    [Pg.2361]    [Pg.169]    [Pg.174]    [Pg.174]    [Pg.176]    [Pg.2071]    [Pg.307]    [Pg.160]    [Pg.400]    [Pg.1007]    [Pg.333]    [Pg.566]    [Pg.102]    [Pg.215]   
See also in sourсe #XX -- [ Pg.332 ]

See also in sourсe #XX -- [ Pg.332 ]




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