APECs

Apec-HTApplication Technology Information, ATI 849e, Mobay Coip., Pittsburgh, Pa., 1992-, Anwendungstechn. Information, ATI 489, Bayer AG, Leverkusen, Germany, 1992. 

Ben-Yaakov, Sam and Gregoiy Ivensky, Passive Lossless Snubbers for High Frequency PWM Converters, Seminar 12, APEC 99. 

The TMC polycarbonate homopolymer has a glass transition temperature of 238°C, nearly 100°C above that of the bis-phenol A polycarbonate. Therefore, copolymers will have intermediate glass transitions depending on the relative proportions of TMC and bis-phenol A. Commercial grades (marketed by Bayer as Apec HT) have Vicat softening points from 158 to... 

Fig. 6 General structures of the most important surfactants and metabolites alkylphenol polyethoxylate (APE) alkylphenol (AP) alkyl ether (AE) alkylphenol ethoxy carboxylate (APEC) linear alkylbenzenesulfonates (LAS) alkyltrimethylammonium compounds (ATMAC) dialkyldimethylammonium compounds (DADMAC) alkyldimethylbenzylammonium compounds (ADMBAC) esterquat (EQ) diesterquats (DEQ). X is usually a chlorine or bromine atom. DDAC (didecyldimethylammonium chloride) and BDD12AC (benzyldimethyldode-cylammonium) are the two target analytes with a reported immunochemical technique developed for their analysis [153,154]...

Several methods, applying MS-MS techniques, for the identification and characterization of APEOs and their metabolites, alkylphenoxy carboxylates (APECs) and alkylphenols (APs) in environmental liquid and solid samples and industrial blends are reported. APCI-MS-MS... 

With gradient elution using methanol-water on a C18 reversed-phase column, APECs, APs, XAPs and XAPECs can be easily separated. 

Petrovic and coworkers [6] used PLE applying MeOH acetone (1 1) for the extraction of APEOs, APECs, APs and their halogenated derivatives from sediment samples. In combination with column-switching LC, using a restricted access material precolumn, hours of sample treatment were saved. 

However, an issue of concern is the relatively high level of alkylphenolic compounds in both water and sediment upstream of known sources of pollution (WWTPs). The concentrations of total alkylphenolic compounds (APEO, AP and APEC) ranged from 5 to 15 jxg L-1 in water and from 0.075 to 0.55 xg g-1 in sediments, and may be attributed mainly to two origins. One is the use of sewage sludge in agriculture and the other is the uncontrolled discharge of industrial wastewaters in the upper course of the river. 

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