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Electronic assemblies statistics

Ionic contamination-expressed in sodium chloride equivalents is primarily used to assess the climatic resistance of electronic assemblies. Ionic measurement is suitable for statistical process control, but it does not furnish an absolute statement concerning the climatic resistance of an assembly. [Pg.918]

BMW Group Standard GS 95003 Electrical/Electronic Assemblies in Motor Vehicles. lEC 600 50(191) (lEV) Dependability and quality of sevices. lEC 60605-4 Equipment reliability testing Part 4 Statistical procedures for exponential distribution Point estimates, confidence intervals, prediction intervals and tolerance intervals. [Pg.790]

In the automobile industry, AEC (Q) 100 is used for complex components. It is a standard for the qualification of electric components. Simple components as resistors or capacitors are not covered in this standard. Since these simple components would often push aU statistic boimdaries through their variety of elements, such statistic observations are often insufficient for safety engineering. The risk for such simple components is that harmful components can be delivered to the production undetected. This is why the eligibility and whether the components are actually sufficiently dimensioned for their case of application are tested in the context of the qualification of the entire electric assembly group. The value for failiue rates is taken from the reliability handbooks. However, for the correct qualification including the proof of lifetime efficiency of the entire electronic assembly group it is assumed that the simple components is within the constant phase of failure rates of the bathtub curve. [Pg.49]

The basic theories of physics - classical mechanics and electromagnetism, relativity theory, quantum mechanics, statistical mechanics, quantum electrodynamics - support the theoretical apparatus which is used in molecular sciences. Quantum mechanics plays a particular role in theoretical chemistry, providing the basis for the valence theories which allow to interpret the structure of molecules and for the spectroscopic models employed in the determination of structural information from spectral patterns. Indeed, Quantum Chemistry often appears synonymous with Theoretical Chemistry it will, therefore, constitute a major part of this book series. However, the scope of the series will also include other areas of theoretical chemistry, such as mathematical chemistry (which involves the use of algebra and topology in the analysis of molecular structures and reactions) molecular mechanics, molecular dynamics and chemical thermodynamics, which play an important role in rationalizing the geometric and electronic structures of molecular assemblies and polymers, clusters and crystals surface, interface, solvent and solid-state effects excited-state dynamics, reactive collisions, and chemical reactions. [Pg.428]

If a metal particle, independent of the element, is reduced in one, two, or in all three dimensions to such an extent that the mobility of the electrons is decisively restricted, one speaks of size quantization because the electrons no longer follow the laws of classical physics based on the statistics of an inflnite assembly of atoms in three dimensions, but rather obey quantum mechanical mles as they are used to describe atoms or molecules. Figure 1 illustrates the formal transition from 3D to a OD state, represented by a so-called quantum dot with three-dimensional quantum confinement. ... [Pg.5941]

Theoretical studies of the properties of the individual components of nanocat-alytic systems (including metal nanoclusters, finite or extended supporting substrates, and molecular reactants and products), and of their assemblies (that is, a metal cluster anchored to the surface of a solid support material with molecular reactants adsorbed on either the cluster, the support surface, or both), employ an arsenal of diverse theoretical methodologies and techniques for a recent perspective article about computations in materials science and condensed matter studies [254], These theoretical tools include quantum mechanical electronic structure calculations coupled with structural optimizations (that is, determination of equilibrium, ground state nuclear configurations), searches for reaction pathways and microscopic reaction mechanisms, ab initio investigations of the dynamics of adsorption and reactive processes, statistical mechanical techniques (quantum, semiclassical, and classical) for determination of reaction rates, and evaluation of probabilities for reactive encounters between adsorbed reactants using kinetic equation for multiparticle adsorption, surface diffusion, and collisions between mobile adsorbed species, as well as explorations of spatiotemporal distributions of reactants and products. [Pg.71]

Odd-even electron numbers and energy level statistics in cluster assemblies... [Pg.1445]

The unique power of the scanning transmission electron microscopy (STEM) technique is its ability to examine isolated unstained structures in projection by mapping boundaries, internal mass distribution, and site-specific cluster labels, as well as measuring total mass. The digital STEM image can be compared directly to a computed projection of a model structure assembled from known or postulated components. If any feature of the proposed model is incorrect, the STEM image will provide direct statistical evidence as to the extent and significance of the discrepancy. This objective approach permits inclusion of a priori information from biochemistry and/or other structural studies to form a self-... [Pg.139]

The construction of systems capable of exhibiting long-range electron transfer requires (he linking of two different chromophores, such as a zinc porphyrin (donor) and a gold(III) porphyrin (acceptor). A statistical approach allows the assembly of the heteroitoiphyrinic compound 127, as indicated in Figure 69. [Pg.35]


See other pages where Electronic assemblies statistics is mentioned: [Pg.92]    [Pg.72]    [Pg.66]    [Pg.506]    [Pg.82]    [Pg.463]    [Pg.130]    [Pg.664]    [Pg.255]    [Pg.101]    [Pg.319]    [Pg.135]    [Pg.99]    [Pg.82]    [Pg.53]    [Pg.455]    [Pg.161]    [Pg.251]    [Pg.268]    [Pg.488]    [Pg.1447]    [Pg.1451]    [Pg.1451]    [Pg.114]    [Pg.143]    [Pg.75]   
See also in sourсe #XX -- [ Pg.770 , Pg.771 , Pg.772 ]




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Electron statistics

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