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Degradation purpose

Another aspect related to control release of drugs concerns the type of structures that currently appear to be working. Not unexpectedly, because of compatibility and degradation purposes, most of the effort on the control release formulations includes polymers that have both a hydrophobic and hydrophilic portion with the material necessarily containing atoms in addition to carbon. Another concern is that the products of degradation are not toxic or do not form toxic materials. It has also been found that amorphous materials appear to be better since they are more flexible and permit more ready entrance of potential degrad-ative compounds. [Pg.598]

It was mentioned earlier that catalytic hydrogenation of protoporphyrin-IX (19) produces mesoporphyrin-IX (46), and that this type of vinyl modification has been used in structural degradation methods. The vinyl group can also be modified for degradative purposes by addition of diazoacetic ester, which produces the corresponding cyclopropane derivatives... [Pg.402]

Batch reactors based on peroxidases are mainly applied for degradation purposes (see Chap. 8). LiP, manganese peroxidase (MnP), HRP, SBP, and CPO were used for the oxidation of phenolic compounds [3, 6, 7, 9, 20, 38, 74, 75, 95], decoloriza-tion of dye-containing effluents [5, 22], and pulp biobleaching [59]. In the field of synthesis, CPO is the most versatile and promising of the peroxidases (see Chap. 6). It was applied in discontinuous operation for epoxidations [78,79], enantioselective oxidations of alcohols to aldehydes [14,48], halogenations [77,80], hydroxylations, and oxidation of indole to oxindole, which is an important drug precursor [96]. [Pg.254]

ADH 4 and ADH 5 can only rarely be demonstrated. Both possess a low affinity with alcohol they are therefore of no importance for degradation purposes. ADH4 is only found in the gastric mucosa. It is to be noted that cimetidine and ranitidine inhibit the ADH of the liver and the gastric mucosa, thus elevating the blood alcohol level. This is, however, not the case with famotidine. In patients with liver disease, ADH activity is reduced - and therefore alcohol degradation as well. [Pg.62]

Degradants (Purposeful Degradation) Key challenge samples Isolated degradants Isolated Fractions Small scale synthesis Phase Equilibrium Supernatants Raw materials Isolated Intermediates... [Pg.147]

The main producers of organic accelerators for mbber vulcanization are shown in Table 3. This table is not meant to be completely comprehensive, but rather to indicate the principal historical suppHers to the mbber industry. Most producers offer chemical equivalents in the largest-volume products. Within the range of smaHer-volume specialty accelerators, chemical equivalents become less common. Each producer may offer different products to achieve the same purpose of rapid cross-linking, resistance to thermal degradation, or other performance characteristics. Many offer proprietary blends of accelerators. [Pg.223]

Cellulose (qv) is one of nature s most abundant stmctural materials, providing the primary framework of most plants. For industrial purposes cellulose is derived from two primary sources, cotton linters and wood pulp. Linters are derived from the machine by the same name used for removing the short fibers adhering to cotton seeds after ginning and consist essentially of pure cellulose (see Cotton). Wood (qv), on the other hand, contains 40—60% cellulose, which must be extracted by the chemical degradation of the wood stmcture. [Pg.248]

Another purpose of inerting is to control oxygen concentrations where process materials are subject to peroxide formation or oxidation to form unstable compounds (acetylides, etc.) or where materials in the process are degraded by atmospheric oxygen. An inert gas supply of sufficient capacity must be ensured. The supply pressure must be monitored continuously. [Pg.38]

For analytieal purposes, eonsider that the mass earrier in the expander with higher temperature and lower pressure eould be thought of as an ideal gas. Beeause exhaust gas pressure and temperature are nearly unehangeable onee seleeted (unless the effieieney degrades), its residual enthalpy may be assumed eonstant. The expander operating eondition mainly depends on the inlet parameters, and the power developed by an expander may be ealeulated from the equation ... [Pg.467]


See other pages where Degradation purpose is mentioned: [Pg.64]    [Pg.83]    [Pg.137]    [Pg.34]    [Pg.163]    [Pg.686]    [Pg.64]    [Pg.83]    [Pg.137]    [Pg.34]    [Pg.163]    [Pg.686]    [Pg.1438]    [Pg.586]    [Pg.589]    [Pg.32]    [Pg.38]    [Pg.205]    [Pg.13]    [Pg.264]    [Pg.269]    [Pg.249]    [Pg.268]    [Pg.423]    [Pg.549]    [Pg.184]    [Pg.45]    [Pg.383]    [Pg.285]    [Pg.274]    [Pg.214]    [Pg.273]    [Pg.438]    [Pg.448]    [Pg.478]    [Pg.243]    [Pg.515]    [Pg.231]    [Pg.271]    [Pg.472]    [Pg.312]    [Pg.540]    [Pg.1095]    [Pg.1190]    [Pg.361]    [Pg.345]    [Pg.654]   
See also in sourсe #XX -- [ Pg.59 ]

See also in sourсe #XX -- [ Pg.59 ]

See also in sourсe #XX -- [ Pg.59 ]




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Method development purposeful degradation

Purposeful degradation

Purposeful degradation definition

Purposeful degradation products

Purposeful degradation samples

Purposeful degradation stability samples

Purposeful degradation studies

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