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Bonded, practical application

The performance of the classifier has been verified using a number of practical applications, such as civil engineering [3], inspection of aerospace composite structures, ball bearings and aircraft multi-layer structures. Here we present shortly some results, focusing on detection of disbonds in adhesively joint multi-layer aerospace structures using Fokker Bond Tester resonance instrument, details can be found in [1]. [Pg.107]

One may wonder why it is important to distinguish between and keep track of these two energies and Dq, when it seems that one would do. Actually, both are important. The bond energy Dg dominates theoretical comparisons and the dissociation energy Dq, which is the ground state of the real molecule, is used in practical applications like calculating thermodynamic properties and reaction kinetics. [Pg.307]

The superacid-catalyzed cracking of hydrocarbons (a significant practical application) involves not only formation of trivalent carbo-cationic sites leading to subsequent /3-cleavage but also direct C-C bond protolysis. [Pg.163]

Rubber used in practical applications is crosslinked through disulfide (-S-S-) bonds, and is known as vulcanized rubber. Can you name another important class of polymers which are crosslinked through disulfide bonds Examine vulcanized rubber. How many individual strands does it comprise Are these strands of natural rubber or of gutta-percha What is the percentage (by weight) of sulfur incorporated into the polymer (The molecular weight of the sample is 1701 amu.) Does this classify as a low-sulfur polymer (<3%), a high-sulfur polymer (>10%) or in between ... [Pg.250]

The main advantage of PEO as a host is that it is chemically and electrochemically stable since it contains only strong unstrained C-O, C-C, and C-H bonds. The disadvantage is the inherent crystallinity, and considerable effort has gone into synthesizing all-amorphous polymer hosts. Unfortunately, with the bulk conductivity as the prime motivator, many amorphous polymer hosts incorporate organic functional groups which limit their practical application. Detailed accounts of many of the hosts synthesized have been reviewed [8, 32-36],... [Pg.504]

The new results of this study Include a clear demonstration of Pt-0 bonds to the support at low temperature In either He or H2. As the temperature Is raised above 600 K the Pt-0 bonds break and the Pt raft-llke clusters curl up to be more sphere-llke. Concurrently with this bond-breaking and change In shape, electrons flow to the Pt d-band. At temperatures above 600 K there Is a d-electron surplus In the Pt clusters compared to bulk Pt, l.e., they are more noble than Pt. This may be a significant result since practical applications of Pt-contalnlng catalysts are In the temperature range where these changes occur,... [Pg.292]

Numerous reactions of carbonyl compounds, alcohols, olefins, etc., with compounds bearing E14=X bonds in which the latter act as direct analogs of phosphorus and arsenic ylides have already been accomplished.17 Recently, an interest in reactivity of compounds with multiple E14-X bonds is increasing due to challenges of important practical applications (see,... [Pg.38]

Some practical applications of non-covalent interactions are also very interesting. The basis of the separation of enantiomers by the chromatographic method21 is the preferential interaction of one enantiomer of a substance with one enantiomer of another substance, which is usually part of the chiral stationary phase. Non-covalent interactions are more frequent hydrogen bonding, host-guest and donor-acceptor interactions. [Pg.427]

Photodimerization of cinnamic acids and its derivatives generally proceeds with high efficiency in the crystal (176), but very inefficiently in fluid phases (177). This low efficiency in the latter phases is apparently due to the rapid deactivation of excited monomers in such phases. However, in systems in which pairs of molecules are constrained so that potentially reactive double bonds are close to one another, the reaction may proceed in reasonable yield even in fluid and disordered states. The major practical application has been for production of photoresists, that is, insoluble photoformed polymers used for image-transfer systems (printed circuits, lithography, etc.) (178). Another application, of more interest here, is the use that has been made of mono- and dicinnamates for asymmetric synthesis (179), in studies of molecular association (180), and in the mapping of the geometry of complex molecules in fluid phases (181). In all of these it is tacitly assumed that there is quasi-topochemical control in other words, that the stereochemistry of the cyclobutane dimer is related to the prereaction geometry of the monomers in the same way as for the solid-state processes. [Pg.179]

Only the silica-based stationary phases with covalently bonded alkyl chain, cyano and propylamino ligands have found practical applications in HPLC. Besides these common ligands, the experimental use of naphthalene, pyrene and nitroaromatic as ligands has also been reported. Silica-based stationary phases with covalently bonded cyclodextrins or cyclodextrin derivatives have been frequently employed in the separation and quantitative determination of isomer pairs. [Pg.19]

The author hopes that this chapter has convinced the readers of the value of homogeneous catalysis for the synthesis of organophosphorus compounds and for organo-heteroatom compounds in a broader sense. Hydrosilylation and hydroboration are indispensable modern synthetic reactions in this category. The H-P addition reactions herein described joins them as a third member. Although this chapter does not cover, the addition reactions of the S-P and Se-P bonds in thiophosphates [39] and selenophosphates [40] to alkynes also proceed in the presence of transition metal catalysts. In view of the wide use of phosphorus compounds, the new procedures will find practical applications. [Pg.53]

The stereoselectivity of different catalysts in catalytic hydrogenations is discussed in the chapter on catalysts (pp. 4, 50). In addition to catalytic hydrogenation, a few other methods of reduction can be used for saturation of carbon-carbon double bonds. However, their practical applications are no match for catalytic hydrogenation. [Pg.41]

The research plan is organized around a set of well-defined model systems and a limited number of detailed experiments. The experiments are designed to progress over a five-year period from fundamental studies on model systems to development of thin film materials with potential practical applications. Together they will form a coherent bond of film growth using LCI with a variety of molecular building and LC solvents. The expected outcomes of this work will be... [Pg.490]


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See also in sourсe #XX -- [ Pg.596 ]




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Practical applications

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