TAILIEUCHUNG - APPENDIX A TO PART 136 METHODS FOR ORGANIC CHEMICAL ANALYSIS OF MUNICIPAL, INDUSTRIAL WASTEWATER 611

Automatic sampler (optional)—The sampler must incorporate glass sample containers for the collection of a minimum of 250 mL of sample. Sample containers must be kept refrigerated at 4°C and protected from light during compositing. If the sampler uses a peristaltic pump, a minimum length of compressible silicone rubber tubing may be used. Before use, however, the compressible tubing should be thoroughly rinsed with methanol, followed by repeated rinsings with distilled water to minimize the potential for contamination of the sample. An integrating flow meter is required to collect flow proportional composites | APPENDIX A TO PART 136 METHODS FOR ORGANIC CHEMICAL ANALYSIS OF MUNICIPAL AND INDUSTRIAL WASTEWATER METHOD 611 HALOETHERS 1. Scope and Application This method covers the determination of certain haloethers. The following parameters can be determined by this method Parameter STORET No. CAS No. Bis 2-chloroethyl ether 34273 111-44-4 Bis 2-chloroethoxy methane 34278 111-91-1 Bis 2-chloroisopropyl ether 34283 108-60-1 4-Bromophenyl phenyl ether 34636 101-55-3 4-Chlorophenyl phenyl ether 34641 7005-72-3 This is a gas chromatographic GC method applicable to the determination of the compounds listed above in municipal and industrial discharges as provided under 40 CFR Part . When this method is used to analyze unfamiliar samples for any or all of the compounds above compound identifications should be supported by at least one additional qualitative technique. This method describes analytical conditions for a second gas chromatographic column that can be used to confirm measurements made with the primary column. Method 625 provides gas chromatograph mass spectrometer GC MS conditions appropriate for the qualitative and quantitative confirmation of results for all of the parameters listed above using the extract produced by this method. The method detection limit MDL defined in Section 1 for each parameter is listed in Table 1. The MDL for a specific wastewater may differ from those listed depending upon the nature of interferences in the sample matrix. The sample extraction and concentration steps in this method are essentially the same as in Methods 606 608 609 and 612. Thus a single sample may be extracted to measure the parameters included in the scope of each of these methods. When cleanup is required the concentration levels must be high enough to permit selecting aliquots as necessary to apply appropriate cleanup procedures. The analyst is allowed the latitude under Section 12 to select chromatographic conditions appropriate for the .

• Hoá dầu
• traditional predictors
• Involvement
• Prostaglandins
• Pathophysiology of Endometriosis
• Genetic Polymorphisms
• Molecular Pathogenesis