Structural losses

LRP4 is another receptor of the LDL receptor gene family involved in regulation of embryonic patterning, mainly controlling formation of limb structures. Loss of receptor activity in gene targeted mice or spontaneous mutation in bovine cause abnormal limb development and... 

CPI Tallies Dock Structure Losses, Chemical Week, Mar. 1, 1969, p. 12. 

The oxidation reaction was investigated using EG concentrations of 0.06 M, 0.2 M, 0.5 M and 1.0 M. In each case, the reference spectrum was collected at —0.85 V after which the potential was stepped to successively higher values. At each step another spectrum was collected and all the spectra were normalised to the reference. A typical result is shown in Figure 2.113(a) which shows the spectra obtained using the 0.5 M EG. The spectra were dominated by a broad structured loss feature extending down from 3000 cm-1 to below 1000cm" . This was attributed by the authors to the loss of OH-... 

Accumulation of homocysteine and reduced transsulfation of various compounds leads to abnormalities in connective tissue structures that cause altered blood vessel wall structure, loss of skeletal bone density (osteoporosis), dislocated optic lens (ectopia lentis), and increased risk of blood clots. 

Ryoo et al. [6] reported an improvement of hydrothermal stability of MCM-41 via so-called salt effects their XRD results didn t show any structural losses for the materials treated in boiling water for only 12 h. Other researchers [1,7,8] also claimed that the hydrophobicity and hydrothermal stability could be improved by trimethylsilylation. However, Pan et al. [9] found that the BET surface area and pore size of the silylated MCM-48 by (CH3)3Si-Cl decreased markedly after silylation, the BET surface area of MCM-48 dropped to about 45%, and pore diameter decreased from 27 A to <16 A, thus retarding the advantages of MCM mesoporous materials possessing high BET surface area and big pore size. 

The AlPOt molecular sieves show excellent physical properties. Many are thermally stable and resist loss of structure at 1000°C. Those studied for hydrothermal stability, including AlP0i,-5, -11, and -17, show no structure loss when treated with 16% steam at 600°C. The layer structures undergo structural collapse when the organic interlayer propant is removed thermally at 200-400°C. 

Fig. 5. Calculated structural loss factor based on RKU model for three-layer composite with varying Young s storage modulus and loss tangent of viscoelastic layer.

Fig. 13. Experimentally determined structural loss factor for three-layer constrained layer assembly as a function of frequency at 5 degrees Centigrade for the formulations listed in Figs. 10 and 11.

Noll, D.A. Maga, L.J. Palladino, D.J. "Computer Programs for Calculation of Structural Loss Factors Using the Ross, Kerwin, and Ungar Model", Research and Development Report DTNSRDC/SAD-87/69E-1944, September 1987, David. W. Taylor Research Center, Bethesda, MD, 20084-5000. 

Evaluation of Structure Loss During Melting/Softening of Biopofymer Gels... 

Standard deviation of gelatinized starch granules Standard deviation of ungelatinized starch granules Structure development rate, dG/dr Structure loss rate, (—dG/dr)... 

Sonographic findings in liver cirrhosis are polymorphic on account of the vastly differing individual hepatic structures (loss of parenchyma, regenerative nodes, connective tissue, fat depositions, compressed hepatic veins, etc.), (s. figs. 6.6, 6.7)... 

The atructural stability of a Variety of commercially available hydrothernally dealuminated Y type zeolitee in high pH ammonium salt eclutions vas studied It was found that such zeolites can lose large amounts of crystallinity, the susceptibility to structure loss increasing with salt concentration and pH, and with increases in both the chemical and framework eilica/alumina ratio of the zeolite ... 

A surprising result was that the structure losses were not due to the high pH s, but rather to a specific reaction involving ammonia. A mechanism originally proposed to account for certain aspects of stress cracking in silicate glasses seems to account for this observation. 

To test this hypotheeisi the stabilities of various conteka HDY s in pH 10 solutions of ethylenediamine (partially hindered H) and tetraiDethylethylenediamine (fully hindered H) were measured. The results are summarized In Table VI and show that while both compounds readily penetrated the zeolites/ ethylenediamine was almost always much leas destructive than ammonia while tetramethylethylenediamine caused no structure loss at all. 

Finally, it was found that the structure losses which some KDY b incur on contact with high pH ajttiimioniuin salt solutions are not the result cf the high pH, but rather a specific attack by a neutral ammonium species. This unexpected result may provide guidance for the development of catalyst manufacturing procedures which will not degrade highly strained zeolites. 

Light elements like O, C, and N will form inclusions above the solubility limits and is found in feedstock as SiC>2, SiC, and Si3N4. These impurities can create problems in the wafering process and during solidification. The consequence can be structure loss in the CZ process and instability in the MC process. 

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