Degradation Tests

In addition, data are available for a study on the degradation of dimethyl-, dibutyl-, and dioctyltin chlorides in soil (Terytze et al, 2000). It is of note that the results of the degradation testing indicate that the diorganotin compounds are partially degraded to the corresponding monosubstituted compounds by way of example, dioctyltin concentrations were observed to decrease from 40 to 12 ng/1 over a 3-month period while the monooctyltin concentration stayed relatively constant at around 2 ng/1. It is therefore likely that only a fraction of dioctyltin decayed to monooctyltin and/or the... 

AU blends were semicrystalfine in nature and the mechanical properties were dominated by the PCL. The initial mass loss was very quickly in the degradation test which was thought to be associated with the rapid degradation of PEO. 

Fungal degradation of BP1 resulted in the formation of 4HB and 4DHB. The levels of these metabolites found after 3 and 6 days of treatment were similar to those achieved in BP3 degradation experiments. Likewise in BP3 degradation tests, THB and DHMB were not detected in any of the collected samples. The levels found of these metabolites were quite low therefore, these products cannot be considered as major degradation products. 

Perjesi P, Kuzmaa M, Fodora K and Rozmera, Z. 2007. Application of crocin bleaching and deoxyribose degradation tests to assess antioxidant capacity of capsaicinoids and some selected flavonoids. Eur J Pharm Sci 32 39. 

Smoke dampers are used to prevent the spread of products of combustion within ventilation systems. They are usually activated by the fire alarm and detection system. Smoke dampers are specified on the leakage class, maximum pressure, maximum velocity, installation mode (horizontal or vertical) and degradation test temperature of the fire. 

To avoid LC conditions involving the use of IP agents—as reported above—an alternative route was reported by Di Corcia et al. [16] for the separation and detection of breakdown products generated out of commercial LAS in a degradation test. This method was based on the conversion of the carboxylic groups into methyl esters. After this modification, the addition of 0.2 M ammonium acetate to the mobile phase sufficed to give sharp peaks. In addition, a 10-fold enhancement of the sensitivity of the ESI-MS detector was obtained. 

The time dependent properties creep and stress relaxation can be considered as tests to monitor degradation or as degradation tests that add mechanical stress. 

DEGRADATION TESTING PROTOCOL INCLUDING GOAL DEGRADATION PRODUCT... 

Tydeman, M. S., and Kirkwood, T. B. L. (1984), Design and analysis of accelerated degradation tests for the stability of biological standards. I. Properties of maximum likelihood estimators, / Biol. Stand., 12,195-206. 

Their conclusions were that many pharmaceuticals would degrade to innocuous substances but that degradation testing should take place as part of the portfolio of drug testing and also that analytical methods available at the time were inadequate to measure the expected concentrations of pharmaceuticals in the environmental matrices concerned. 

TABLE 2. Composition of Acid Used in Degradation Tests to Simulate Waste Acid... 

Brouns, T. M., and T. L. Stewart. 1988. Waste Acid Detoxification and Reclamation Final Phase II Report - Material Degradation Tests for FY 1987 and FY 1988. PNL-6651... 

SCI WGI Industrial, chemical and oil hoses SCI WG2 Automotive hose SCI WG3 Hydraulic hose SCI WG4 Hose test methods SC2 Physical and Degradation Tests SC2 WGI Physical properties SC2 WG2 Viscoelastic properties SC2 WG3 Degradation tests SC2 WG4 Application of statistical methods... 

Figure 20. Strain-to-break for Nafion 117 (left) and NRE-212 (right) membrane samples before and after Fenton degradation test.

Comparing to the accelerated life test where only the life distribution under a given stress level is recorded, the accelerated degradation test keeps track of the evolution of a damage metric (Fr), which allows the experimental validation of the correlation approach if the selected damage metric is observable. For example, the projected life distribution under normal stress can sometime... 

Figure 25. Concept of accelerated life and accelerated degradation test T1 and T2 are two stress levels and T3 is the normal stress level PI, P2, and P3 are the life distribution under stress level Tl, T2, and T3.

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