Nebraska samples

During re-entry, stratified whole-leaf sampling was conducted. Twenty-four leaves from the harvesting zone of the crop were collected in a 500-mL polyethylene bottle in duplicate. Leaf samples were stored at 4 to 7°C in the laboratory until analysis. After analysis, the leaf volume was measured by stereometric volumetry using a method described by Sherle (1970). A linear relationship between leaf volume and leaf area was determined for carnation leafs by measuring leaf area (one-sided) with a LI-COR 3100 (Ll-Cor, Inc. Nebraska). 

Numerous sampling activities have been conducted in Iowa, Kansas, Nebraska, and Missouri since the initial detection of carbon tetrachloride at Waverly. 

The Nebraska Department of Environmental Quality, Nebraska Department of Health and Human Services, and the EPA has sampled 308 former USDA/CCC grain storage facilities. These efforts revealed 80 locations (26%) had detections of carbon tetrachloride, with 35 (11%) of these locations exceeding the drinking water standard of five micro grams per liter. 

As a result of these sampling efforts two locations (Bruno, Nebraska and Waverly, Nebraska were placed on EPA s National Priorities List (NPL) for clean-up of carbon tetrachloride contamination. The EPA entered into an Administrative Order on Consent with USDA for the groundwater contamination at Murdock, Nebraska. All locations that had detections that exceeded the drinking water standard were provided alternate sources of drinking water (i.e., bottled water, connection to public water supply). 

Allison Trentman and B.J. Kronschnabel of the City of Lincoln, Nebraska, Water Treatment Plant Laboratory take samples of drinking water from a distribution system sampling site. 

Tai Van Ha of the Nebraska State Agriculture Laboratory inspects a sample of fertilizer that is obviously not homogeneous. There are various light- and dark-colored granules of fertilizer in the bag. 

In the laboratory for the electroplating facility at Molex, Inc., Lincoln, Nebraska, seventeen plating baths set up for tin and tin-lead electroplating must be tested three times daily for acid content. The procedure involves an acid-base titration using standard sodium hydroxide as the titrant. Because the volume of samples is so large, an automatic bottle-top buret is used with a 2-gal bottle filled with the standard sodium hydroxide solution. 

In order to determine chemical elements in soil, samples of the soil must undergo a solid-liquid extraction. Sometimes the extracts resulting from this procedure have analyte concentrations that are too high to be measured accurately by the chosen method. Therefore, they must be diluted. At the Natural Resources Conservation Service (NRCS) Soil Survey Laboratory in Lincoln, Nebraska, an automated diluting device is used. Using this device, the analyst accurately transfers aliquots of the extract and a certain volume of extraction solution to the same container. This dilutor may also be used to pipet standards and prepare serial dilutions. 

Left, interchangeable colored glass filters used in a flow injection analyzer for different analytes. Notice the value of the wavelength inscribed on the edge of each filter. Right, Steve Kruse of the City of Lincoln, Nebraska, Wastewater Treatment Plant Laboratory prepares to change the filter in the instrument as he prepares to test for a different analyte in wastewater samples. 

Randy Karl of MDS Pharma Services in Lincoln, Nebraska, examines a centrifuge tube containing a heparinized plasma sample prior to performing an extraction procedure using ethyl acetate. 

Stephanie Marquardt, a technician in the bioanalytical laboratory at the MDS Pharma Services laboratory in Lincoln, Nebraska, prepares open columns for the preparation of urine samples for analysis for mutagens. 

Ion chromatography is used at the City of Lincoln, Nebraska, Water Treatment Plant Laboratory to analyze water samples taken from sampling sites in the distribution system around the city. The common anions determined by IC are not only nitrate, nitrite, fluoride, and sulfate, but also bromate. Bromate is found in the water because the Lincoln plant treats the water with ozone. Adding ozone to the water oxidizes any bromide to bromate. Bromate is regulated at 10 parts per billion (ppb) its concentration must be determined. 

The progress made in interfacingHPLC instruments with mass spectrometry has been a significant development for laboratory analyses in the pharmaceutical industry. The low concentrations of test drugs in extracts of blood, plasmas, serums, and urine are no problem for this highly sensitive HPLC detector. In addition, the analysis is extremely fast. Lots of samples with very low concentrations of the test drugs can thus be analyzed in a very short time. At the MDS Pharma Services facility in Lincoln, Nebraska, for example, a very busy pharmaceutical laboratory houses over 20 LC-MS units, and they are all in heavy use daily. 

In Nebraska, state regulations require that the chemical makeup of animal feed sold in the state be accurately reflected on the labels found on the feed bags. The Nebraska State Agriculture Laboratory is charged with the task of performing the analytical laboratory work required. An example is salt (sodium chloride) content. The method used to analyze the feed for sodium chloride involves a potentio-metric titration. A chloride ion-selective electrode in combination with a saturated calomel reference electrode is used. After dissolving the feed sample, the chloride is titrated with a silver nitrate standard solution. The reaction involves the formation of the insoluble precipitate silver chloride. The electrode monitors the decrease in the chloride concentration as the titration proceeds, ultimately detecting the end point (when the chloride ion concentration is zero). 

Charlie Focht of the Nebraska State Agriculture Laboratory refills a saturated calomel electrode with saturated potassium chloride while preparing to analyze animal feed samples for sodium chloride via a poten-tiometric titration. 

Larry Arnold, a technician with the National Soil Survey Laboratory in Lincoln, Nebraska, prepares soil samples for particle size analysis. 

John Howe, an analyst in the laboratory of MDS Pharma Services in Lincoln, Nebraska, checks an auto-sampler tray used with an HPLC instrument in the analysis of biological samples for drugs. A given run may include a large number of sample extracts to run alongside quality controls and standards, hence the need for an auto-sampler. 

Alachlor was found In two wells out of 14 sampled In Nebraska at about 0.04 ppb In a monitoring study which focused on atretzlne high use areas (24). These corn growing areas were known to have sandy soils and a shallow, unconflned aquifer. The wells sampled were assumed to be representative of over 1,000 wells located In the study area. 

Atrazlne has been found in ground water in Nebraska (24,43, 56,57), Wisconsin (54), and Iowa (55). The concentrations in several dozen wells were typically 0.8 ppb. The four positives out of nine wells sampled in Iowa were associated with an adjacent river which was contaminated with atrazlne by runoff. In 1979 and 1980, positive correlations between atrazlne and nitrate in ground water were reported (56,24). It has been estimated that 0,07% of the atrazlne applied to the surface leached to a 1.5 m depth in Nebraska (57). 

Olson, R.A., Rhodes, M.B. and Dreier, A.F. (1954) Available phosphorus status in Nebraska soils in relation to series classification, time of sampling and method of measurement. Agronomy Journal 45, 175-180. 

Elemental analysis was performed by Galbrith Labs., Knoxville, TN. Mass spectrometry was carried out by the Midwest Center for Mass Spectroscopy, University of Nebraska, Lincoln, NB. Samples were inserted in a glass ampule using a direct insertion probe (DIP-EI-MS). A Kratos MS-50 Mass Spectrometer was used. Spectra were recorded for samples ballistically heated to 450 C. 

High resolution electron impact mass spectral analyses were carried out at the Midwest Center for Mass Spectrometry, University of Nebraska, Lincoln, Nebraska. The samples were rapidly heated to about 450 C. 

Variation among Sampling Sites. Dissolved humic substance samples from seven end-member environments were isolated for study. Autochthonous inputs to DOM were expected to dominate in Big Soda Lake and in Island Lake, which is a groundwater-sustained eutrophic lake in the sandhills of western Nebraska. Allochthonous inputs to DOM from a swamp environment predominate in the Suwannee River. They also dominate in the Calcasieu River in western Louisiana, but the proportion of swampland is much lower there. The Temi River is a tropical blackwater tributary of the Orinoco River in Venezuela, where allochthonous inputs dominate. The entire Sagavanirktok River basin is located north of the tree line on the North Slope of Alaska a mixture of allochthonous and autochthonous inputs was expected for the various rivers and lakes in this basin. Lastly, Hidden Lake Creek, which is the outlet of Hidden Lake on the Kenai Peninsula of Alaska, was sampled to determine if nutrient inputs from decaying salmon were contributing to primary production and autochthonous inputs to DOM. 

Samples of DOM from the Sagavanirktok River and Hidden Lake Creek in Alaska and from Island Lake, Nebraska, were collected and analyzed with the assistance of Patricia A. Brown, Eric A. Stiles, and Ted I. Noyes of the U.S. Geological Survey, Denver, Colorado. Jeffrey Koenings of the Alaska Fish and Game Department, Soldotna, Alaska, suggested and coordinated the Hidden Lake Creek study. Thomas C. Winter and James W. LaBaugh suggested and coordinated the Island Lake, Nebraska, study. 

Harlan County Lake (Reservoir), Nebraska, USA 15 sediment core samples Weathered shales and other rocks agricultural irrigation drainage 5.7-9.0 Christensen and Juracek (2001)... 

USA Midwest (Western Interior) Arkansas, Iowa, Kansas, Missouri, Nebraska, Oklahoma mostly bituminous 311 samples USA Midwest (Western Interior) Kansas bituminous 32 samples USA National Average... 

Unpublished data. Atmospheric samples taken during the summer of 1936 after the dust clouds from the Dust Bowl reached Washington, D. C., showed concentrations as high as 250 mg per cu cm at breathing level. Settled dust samples from various localities in Kansas and Nebraska were furnished the author by Dr. James Leake of the U. S. Public Health Service. The samples were air-elutriated and fractions submitted for both petrographic and chemical analysis. 

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