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Higher-order methods summary

In summary, nonlinear optical imaging methods, such as TPM, allow for an order of improvement in the signal simply by utilization of 10 times shorter pulses. The enhancement is even more dramatic for higher-order nonlinearities, such as third harmonic generation where two orders of magnitude increase is expected. These improvements, however, rely on successful measurement and elimination of phase distortions. [Pg.210]

Because of the higher heat-transfer rates, dropwise condensation would be preferred to Him condensation, but it is extremely difficult to maintain since most surfaces become wetted after exposure to a condensing vapor over an extended period of time. Various surface coatings and vapor additives have been used in attempts to maintain dropwise condensation, but these methods have not met with general success to date. Some of the pioneer work on drop condensation was conducted by Schmidt [26] and a good summary of the overall problem is presented in Ref. 27. Measurements of Ref. 35 indicate that the drop conduction is the main resistance to heat flow for atmospheric pressure and above. Nucleation site density on smooth surfaces can be of the order of 10 sites per square centimeter, and heat-transfer coefficients in the range of 170 to 290 kW/m2 °C [30,000 to 50,000 Btu/h ft2 °F] have been reported by a number of investigators. [Pg.492]

Summary The rich variety of the coordination chemistry of silicon is discussed and some theoretical issues are raised. In an attempt to understand further the underlying chemistry, some thermodynamic and kinetic parameters for the formation and substitution of pentacoordinate silicon compounds have been measured by NMR methods. Values of -31 3 kJ mol for SHand -100 10 J K mor for A5-were measured for the intramolecular coordination of a pyridine ligand to a chlorosilane moiety. A detailed kinetic analysis of a nucleophilic substitution at pentacoordinate silicon in a chelated complex revealed that substitution both with inversion and retention of configuration at silicon are taking place on the NMR time-scale. The substitution with inversion of configuration is zero order in nucleophile but a retentive route is zero order in nucleophile at low temperature but shows an increasing dependence on nucleophile at higher temperatures. These results are analysed and mechanistic hypotheses are proposed. Some tentative conclusions are drawn about the nature of reactivity in pentacoordinate silicon compounds. [Pg.411]

In summary, this series of studies on Nd -diketonates demonstrate that luminescence properties are enhanced when the fluorinated chain is lengthened. As a consequence, attempts have been made to use the benzoylacetonate derivatives 48e and 48f in luminescence determination of lanthanides in order to improve the sensitivity of the method. Luminescence intensities for Nd and Yb chelates formed with 48e and 48f are higher by a factor 1.2-1.6 than those observed for the ternary complexes formed with tta and phen. Although highly sensitive detection of Nd and Yb can also be achieved using tris complexes only, ternary... [Pg.292]

Current applications of MS/MS for amino acids are predominantly for screening purposes, especially in newborns, and follow-up confirmatory tests are necessary. Transient tyrosinemia, for example, is quite common in the newborn, and follow-up is perhaps advisable only if clinically indicated, or if tyrosine levels remain elevated 2-3 weeks after birth. In most cases, the amino acid elevations are marked (>5x normal mean) and follow-up tests are ordered promptly, otherwise a repeat screen is ordered. Follow-up testing is not necessary if the second screen is normal. Sulfocysteine levels in affected patients are more than an order of magnitude higher than in normal controls. A summary of the amino acids for which validation of the MS/MS method has been carried out, and the disorders associated with their elevation, is provided in Table E.2. [Pg.76]

The numerical results show the efficiency of the new obtained methods. In summary In the author produced P-stable super-implicit and Obrechkoff methods. It is known that the advantage of Obrechkoff methods is that they are high-order two-step or four-step methods (in our cases) and thus will not require additional starting values. They require higher derivatives of the right-hand side. In cases of very complex problems, the use may prefer super-implicit methods. In this paper super-implicit P-stable method of order 12 and an Obrechkoff method of order 18 have been obtained. [Pg.263]


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See also in sourсe #XX -- [ Pg.271 ]

See also in sourсe #XX -- [ Pg.415 ]




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Higher-order methods

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