Sampling equipment, water

F.D. Wilde, D.B. Radtke, J. Gibs, and R.T. Iwatsubo, Cleaning of Water Sampling Equipment , in National Field Manual for the Collection of Water-Quahty Data , US Geological Survey Techniques of Water Resource Investigations, US Geological Survey, Reston, VA, Book 9,... 

To decontaminate water sampling equipment (pumps, water level meter, bailers), we... 

Sampling. A rather wide variety of sampling techniques was used. In general, they were selected for ease of adaptation to the local situation. The water sampling equipment was as follows ... 

Figure 1 Pictures of black smokers. (A)- C) Brandon Vent a black smoker with 405°C fluid temperatures on the Southern East Pacific Rise at 21°33 S at a depth of 2834m in (A) and (B), shown instrumented with a Hobo recording temperature probe and in (C) with one of Alviiis manipulators. (D) Nadir vent at 17°26 S at a depth of 2562 m and fluid temperatures of 343°C shown prior to sampling in 1998. In the foreground is Alviiis basket with water sampling equipment. (E) Water sampling of Nadir vent fluids.

The recent development and comparative application of modern separation techniques with regard to determination of alkylphosphonic acids and lewisite derivatives have been demonstrated. This report highlights advantages and shortcomings of GC equipped with mass spectrometry detector and HPLC as well as CE with UV-Vis detector. The comparison was made from the sampling point of view and separation/detection ability. The derivatization procedure for GC of main degradation products of nerve agents to determine in water samples was applied. Direct determination of lewisite derivatives by HPLC-UV was shown. Also optimization of indirect determination of alkylphosphonic acids in CE-UV was developed. Finally, the new instrumental development and future trends will be discussed. 

For MPN determination, sterile pipettes calibrated in 0.1-ml increments are used. Other equipment includes sterile screw-top dilution bottles containing 99 ml of water and a rack containing six sets of five lactose broth fermentation tubes. A sterile pipette is used to transfer 1.0-ml portions of the sample into each of five fermentation tubes. This is followed by dispensing 0.1 ml into a second set of five. For the next higher dilution (the third), only 0.01 ml of sample water is required. This small quantity is very difficult to pipette accurately, so 1.0 ml of sample is placed in a dilution bottle containing 99 ml of sterile water and mixed. The 1.0-ml portions containing 0.01 ml of the surface water sample are then pipetted into the third set of five tubes. The fourth set receives 0.1 ml from this same dilution bottle. The process is then carried one more step by transferring 1.0 ml from the first dilution bottle into 99 ml of water in the second for another hundredfold dilution. Portions from this dilution bottle are pipetted into the fifth and sixth tube sets. After incubation (48 h at 35 C), the tubes are examined for gas production and the number of positive reactions for each of the serial dilutions is recorded. 

Equipment, facilities, supplies, tools, and utility services (e.g., PPE, sampling equipment, instrumentation, hot/cold water, electricity, sewage treatment). 

Environmental monitoring of chloroacetanilides requires methods that have the capability to distinguish between complex arrays of related residues. The two example methods detailed here for water monitoring meet this requirement, but the method for metabolites requires sophisticated mass spectral equipment for the detection of directly injected water samples. In the near term, some laboratories may need to modify this method by incorporation of an extraction/concentration step, such as SPE, that would allow for concentration of the sample, so that a less sensitive and, correspondingly, less expensive, mass spectral detector can be used. However, laboratories may want to consider purchasing a sensitive instrument rather than spending time on additional wet chemistry procedures. In the future, sensitive instrumentation may be less expensive and available to all laboratories. Work is under way to expand the existing multi-residue methods to include determination of additional chloroacetanilides and their metabolites in both water and soil samples. 

They describe the development of a system employing a Tenax GC filled purge and trap sampler, which collects and concentrates volatile organotins from water samples (and species volatilised by hydrodisation with sodium borohydride), coupled automatically to a gas chromatograph equipped with... 

Sampling Methods From the outset of the high density lake sampling program in 1987, the application of a robust and consistent sampling protocol was considered paramount and this is still the case. Lake sediment and water sampling is performed by 2-person teams primarily from float-equipped Bell 206B helicopters. 

Study, SPE sampling of >6>C-associated residues cannot be ruled out. Also, no data are available on the potential of the surficial retention of colloids or DOC by the SPE sorbent. These factors would lead to an overestimation of dissolved concentrations. Other sampling equipment may also yield inaccurate measurements of dissolved concentrations. Pre-equilibration of laboratory exposure systems is a separate issue related to attainment of steady-state water concentrations in the exposure system prior to initiation of the test. Clearly, the issue of DOC or colloidally sorbed contaminants deserves additional discussion. 

Since the level of tritium in the atmosphere is presently greater than 10 TU, it is possible to study many physical and chemical processes using this equipment for sample analysis. Since isotopic enrichment is unnecessary for most samples, direct rapid analysis is possible. The equipment is being used presently to analyze water samples from Nevada in a hydrology project. Table IV shows the analytic data. No attempt has yet been made to evaluate these data. What is apparent qualitatively... 

The condensation reaction was carried out in a stirred 50 cm3 glass flask under a reflux condition. The reaction temperature was maintained by a heated silicon oil bath surrounding the reactor, and measured by a mercury thermometer immersed into the reaction mixture. After the reaction, the solid product and catalyst were separated from the reaction solution by filtration. The product was dissolved in ethyl acetate and separated from the catalyst particles by another filtration. The product was washed by water and then dried over MgS04. Analysis of the product was made with a 1IPLC (Waters 990) equipped with a —Porasil column. A 30% ethyl acetate in hexane was used as an eluent. The conversion of IICHO, the limiting reactant, was calculated from the isolated solid product. The selectivity was calculated by comparing the peak area of the main product with that for an authentic 4,4 —MDU sample. 

High-performance liquid chromatograph (HPLC e.g., Waters Chromatography) equipped with column heater, solvent pump, UV detector (set at 210 nm), integrator, autosampler, and (for manual injection) a 10-pl sample loop 15 x 0.46-cm YMC-ODS-AQ analytical column (AQ12S031546WT, Waters Chromatography)... 

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