Partially stable

This benzyl ether is partially stable to BF3 Et20 as used in glycosylation reactions and NaOMe, but is not stable to TFA at it for 30 min. 

The Phacm group is stable to the following conditions DIEA-CH2CI2, TFA-CH2CI2, piperidine-DMF, 0.1 M TBAF-DMF, and DBU-DMF for 24 h at It to HF-anisole or / -cresol (9 1) at 0° for 1 h and to TFA-scavengers (phenol, HSCH2CH2SH, p-cresol, anisole) for 2 h at 25°. It is partially stable (>80%) to TFMSA-TFA-/ -cresol for 2 h at 25°. These stability characteristics make the group compatible with BOC- or Fmoc-based peptide synthesis. ... 

The therapeutic success is measured by its effect on tumor size and can be described as tumor remission (complete or partial), stable disease, or progression of the tumor. Also, the impact of a therapy is related to time and can be measured as disease free interval, time to progress, or overall survival time. 

The ZW, FW, and UW are in most instances a consequence of product stability. In a situation where the intermediates are unstable, it is always advisable to proceed with the subsequent step(s) in the recipe as soon as the intermediates are formed, hence the ZW operational philosophy. Due to its nature, ZW does not require any dedicated storage for the intermediates and could be depicted by a flowsheet similar to that shown in Fig. 1.3. On the other hand, the intermediate could be partially stable and only commence decomposition after a certain period. In this case storage time has to be finite in order to prevent formation of unwanted material, hence the FW operational philosophy. The UW operational philosophy is applicable whenever the intermediates are stable over a significantly longer time than the time horizon of interest. In both FW and UW operational philosophies, storage of intermediates can either be within the processing equipment or dedicated storage unit. 

Various types of crack propagation, namely unstable, partially stable, and fully stable can be observed during SENB tests [85,131]. Solvent-modified epoxy networks prepared via CIPS with 13-16 wt % and 22 wt % cyclohexane show unstable crack propagation. For solvent-concentrations of 18 wt % and 20 wt % cyclohexane, a partially stable crack propagation is observed. The amount of energy consumption upon crack propagation is only 10% and 14% respectively for these two compositions. The change in the fracture behavior indicates that the... 

From the discussion presented above, it is clear that the stability of the debond process can be evaluated by a single parameter, Zmax, which is the shortest (remaining) bond length needed to maintain the debond process stable, and is a constant for a given composite system. Therefore, three different interface debond processes are identified in the following totally unstable, partially stable and totally stable debond processes. The schematic plots of the applied stress versus displacement curves are illustrated in Fig. 4.25 for these debond processes. 

Fig. 4.25. Schematic presentations of applied stress versus displacement (

Effect of Wood Moisture. It has been recommended that for acetylation with acetic anhydride, the moisture content of wood should be about 2% as excess moisture is likely to react with acetic anhydride and produce acetic acid (37). Goldstein et al. (28) observed that raising the moisture to 22% considerably slowed the reaction and each 1 percent of moisture in wood would lead to hydrolysis of about 5.7% acetic anhydride. Low moisture contents are not possible to attain in commercial treatment of wood. With ketene gas it has been possible to acetylate wood with as high as 20% moisture content with WPG about 25% (40). Thioacetic acid is only partially stable in cold water and dissociates at higher temperatures. The presence of moisture in wood could thus be critical in treatments with thioacetic acid also. Results of mango treated at 5 different moisture levels are depicted in Figure 3. As may be seen a moisture content up to 7.5% has no adverse effect on WPG. At 10% moisture content the WPG decreased to 4.6. With further increase in moisture, there was a gradual decrease in WPG attained. 

The in vivo metabolism of capecitabine (1) to the active tumor cytotoxic substance 5-fluorouracil (5) is now fairly well understood. When capecitabine is administered orally it is delivered to the small intestine, where it is not a substrate for thymidine phosphorylase in intestinal tissue, and so passes through the intestinal mucosa as an intact molecule and into the bloodstream. When 1 reaches the liver, the carbamate moiety is hydrolyzed through the action of carboxylesterase enzymes, liberating 5 -deoxy-5-fluorocytidine (5 -DFCR, 10). DFUR is partially stable in systemic circulation, but eventually diffuses into tumor cell tissue where it is transformed into 5 -deoxy-5-fluorouridine (5 -DFUR, 9) by cytidine deaminase, an enzyme present in high concentrations in various types of human cancers compared to adjacent healthy cells (although it is present in significantly lower levels in the liver). Within the tumor, 5-... 

In 1993, Molander found that in the presence of catalytic Fe(III) salts, Sml2 mediates intramolecular Barbier additions to esters to give cyclic ketones (or cyclic hemiketals, if they prove to be stable).135 Double addition to the ester is not observed, nor is reduction of the cyclic ketone product. This suggests that the tetrahedral intermediate, a samarium alkoxide of a cyclic hemiketal, is partially stable to the reaction conditions and the ketone group is not revealed until work-up. Molander found that both alkyl and allyl halides could be used in the additions (Scheme 5.83).135... 

Figure 15.8 Various partially stable configurations (outcome of relaxing Hj) with the corresponding adsorption energies (a) E= 54meV, (b) A = 114 meV, (c) A.E— 80meV, (d) AE — 56meV, (e) AE — 67meV, and (f) AE = llOmeV. (Reprinted with permission from Refs [25, 83] Copyright 2003 by the American Institute of Physics.)...

CRACK GROWTH Fully stable Partially stable then unstable Fully unstable after Fmax Fully unstable ... 

Transition 0 fully stable to partially stable fracture Below this transition, the whitened zone covers 100% of the fracture surface (see Figure 5d)... 

Transition I partially stable to fully unstable fracture Energy for initiation and propagation cannot be separated (Figure 5c) (drastic drop in force at Fmax)... 

Some columns require special care. Amino columns, for example, should not be exposed to solvents that contain aldehyde or keto groups. Amino columns also are only partially stable in an aqueous environment. When exposed to water, the high concentration of bond phase in the pores creates a strongly basic environment. Under these circumstances, the silica surface dissolves slowly, creating acid silanols. At some point, the acidic silanols neutralize the local basic environment, and the dissolution of the phase is slowed down or even halted. Since amino columns are often used in an aqueous environment as ion exchangers or for the analysis of carbohydrates, you should be aware of this effect. 

Hi) Homocitrulline. This derivative is formed from reaction of lysine with cyanate (Stark, 1965). It may be employed for the same reasons as described for homoarginine (although the charge conservation is lost) and is also encountered as a by-product of the cyanate end-group procedure of Stark and Smyth (1963). It is only partially stable to acid hydrolysis, some 25% being degraded to lysine in 24 hr under the normal conditions of acid hydrolysis. 

Silk I, the prespun pseudocrystalline form of silk present in the gland in a water-soluble state, remains without a consensus structure in the field and likely represented by many partially stable states. Many models have been proposed and likely reflect many local minima... 

While the asphaltene and resin fractions alone provide a partially stable film, the combination of resin and asphaltene produce extremely stable films. However, additional information is needed to confirm our assumptions that the films have a multilayer structure at lower diluent ratios and a bilayer structure at high diluent ratios. We hope that future measiuements of the disjoining pressiue-thickness isotherms will provide this confirmation as well as identify the surface forces that stabilize the water/diluted-bitumen/water films. 

Diethoxycyclopropenone, which is formally the diethyl ester of deltic acid has been prepared similarly by irradiation of diethoxy-cyclohutenedione [150]. It is very hygroscopic and is partially stable to cold alkali or acid but resinifies quickly when heated with 10% hydrochloric acid. 

A calculated partial stable liquidus surface in the iron rich comer, shown in Fig. 7, has been reported by [1996Koc] at 8 GPa based on the experimental work done by [1978Kam]. 

Figure 14.16 Crack growth resistance curves in partially stable zirconia (Mg-PSZ). The first two digits of the nomenclature show the average grain size, in microns. From Ref. [16].

This classification system aims to link management and prognostic evaluation with the imaging findings. It is based on the work of Tile and the Association for Osteosynthesis and relates to the site of fractures within the pelvic ring (Fig. 12.15a-c). There are three classifications, A, B and C. In type A fractures, the pelvic ring is stable, type B is partially stable this includes the open-book and bucket-handle fractures which are caused by external- and internal-rotation forces, respectively. In type C injuries, there is complete disruption of the posterior sacroiliac complex. In adults, type A lesions represent 52%, type B 27% and type C 21% (Theumann et al. 2002). The classification is shown in Table 12.1. 

Fig. 12.15a-c. The Tile classification. The black areas represent fracture zones. No displacement of the posterior arch. Incomplete disruption of the posterior arch (partially stable). Complete disruption of the posterior arch (unstable)... 

Type B1 External rotation or Bl.l unilateral antero- or Partially stable (complete rupture of... 

Fi 7.11 An electric displacement D as a function of the mechanical stress Ti (schematically), (a) Fully reversible twinning, (b) Partially stable twins... 

Other problems have to do with only partially stable stereocenters. New approaches to this class of problem have been proposed recently. ... 

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