Research Retention

When a new impurity is encountered during chemical process research, retention time and molecular weight information are compared to the database for rapid identification. This approach is similar to the procedure described for natural product dereplication. If the compound is not contained in the structure database, then the corresponding LC/MS/MS analysis is performed to obtain substructural detail and the proposal of a new structure. 

Dependences of retention time, limit of detection with nature and stmcture of analyzed substances were investigated. Chemically pyrethriods are derivatives of cyclopropanecarbonic acid. Researches have shown, that pyrethriods retention times depends on nature of assistants and increase with introduction into molecule of complex radicals (phenoxybenzyl-) or polar assistants (C1-, Br-, CN-groups). 

Many studies have examined the efficacy of a variety of psychosocial treatments for alcohol, cocaine, and opioid use disorders, alone and in conjunction with pharmacotherapy. However, only a handful of studies have explored how these two treatment approaches may interact. More research is needed to further explore the ways in which psychosocial interventions may be used in conjunction with pharmacotherapy to optimize outcomes for both treatments. Providing encouragement for abstinence, greater treatment retention, medication adherence, and coping with medication side effects are some potential applications of psychosocial therapies. 

Abdellatif M, Thakkar B, Motyka D. Constructing data retention CDs for the VA CSP 399 participating sites after trial completion. Hines VA Research Day 2003 P39. 

Data on the pectin content of the initial material (AUAC and DE) is presented in Table 1. It is evident that the main difference between the two lots of oranges was in their anhydrouronic acid content. Observations from previous research (1) were confirmed that microwave heating of the fresh material ensured better drying conditions by inactivating pectolitic enzymes, particularly pectinesterase. Thus a better retention of the degree of esterification of pectin was ensured. 

Separation and detection methods Very refined chromatographic and electrophoretic separation techniques have been developed for metallothioneins. The detection is commonly based on the retention time and UV detection. Other researchers measured the element with e.g. ICP-MS to quantify the compotmd. Combination with electrospray MS-MS leads to the unequivocal identification of the species. 

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