Length variation

When points for 20-ft-long tubes do not appear in Fig. 11-41, use 0.95 times the cost of the equivalent 16-ft-Iong exchanger. Length variation of steel heat exchangers affects costs by approximately 1 per square foot. Shell diameters for a given surface are approximately equal for U-tube and floating-head construc tion. 

Index of aromaticity based c bond-length variation (benzene = 100). ... 

Further, if a certain distorted structure and its countertype in which the bond-length variation is reversed are not equivalent (e. g., the two Kekule-type structures in IV), these two structures should be differentiated as a starting geometry. 

Table 17. Average metal-ligand bond lengths R for HS and LS isomers and bond length variation AR for complete HS <-> LS conversion of spin transition compounds...

W. H. Baur, Bond length variation and distorted coordination polyhedra in inorganic crystals. Trans. Am. Crystallogr. Assoc. 6 (1970) 129. 

The electrocontractile response of a composite of a PVA-PAA gel doped with PPy has been investigated by a group in the University of Pisa [70], The composite strip (initial length 3.05 cm, thickness 0.016 cm) in a 0.05 N NaCl solution has acted as both an electrode and an actuator. When dc voltages up to 2 V were applied, PPy doped in the gel underwent a redox reaction to change the pH inside the gel, and the change in size was observed within 30 min. The measured length variation was about 2%. 

McKean, D. C., J. E. Boggs, and L. Schafer. 1984. CH Bond Length Variations Due to the Intramolecular Environment a Comparison of the Results Obtained by the Method of Isolated CH Stretching Frequencies and by Ab Initio Gradient Calculations. J. Mol. Struct. 116, 313-330. 

Since the distance between the zeroes, in terms of sample length variation, is A/4, the total contraction of the sample is AL = N A/4, where N is the total number of zero crossing. The resolution of the system is basically A/4, but it could be improved with an evaluation of fractions of a fringe. 

The computational bond-length variations in Table 4.53 exhibit the expected periodic trends. Most noticeably, third- and second-series elements for groups 4, 6, and 10 exhibit similar bond lengths, i.e., the post-lanthanide contraction with respect to the ordinary increase of atomic size with increasing Z. 

The substitution at the 3-position in the acyl side chains is important for the agonistic activity of AHLs, but so far no clear prediction on the antagonistic effect of a modification at this position can be made [57]. Recently however, the biological impact of chain length variation and hydroxylation of C6-HSL was investigated [70]. Based on the halofuranone 26 from Deliseapulchra, a small... 

These bond length variations have been rationalized in terms of different degrees of ring 7t-bonding within a molecule. Strong electronegative substituents contract the d-orbital at the phosphorus atom and make them less available for... 

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