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Acetylene fermentation assays, nitrogen fixation assays, and growth studies were performed with Pelobacter sp. strain SFB93 and Pelobacter acetylenicus DSM3246. Data includes concentrations of acetylene and ethylene over time, and growth measured with OD680 and cell counts.
2016 four-figure standard and conventional atomic weights of the chemical elements
Survival, growth and reproduction of the amphipod Hyalella azteca in 42-d water only treatments with and without the addition of bromide
Poor survival, growth and reproduction of the amphipod Hyalella azteca has been observed in exposures using reconstituted waters. Previous studies have reported success in H. azteca water-only exposures with the addition of relatively high concentrations of bromide (Br). This study evaluated the influence of lower environmentally representative concentrations of Br on the response of the amphipod H. azteca in 42-d water-only exposure conditions in various reconstituted waters. Improved performance of H. azteca was observed in reconstituted waters with >0.02 mg Br/L. These tables and figures provide online supplemental information that will not be included in the journal article.
The vernal pool fairy shrimp, Branchinecta lynchi, (Branchiopoda; Anostraca) and other fairy shrimp species have been listed as ‘threatened’ or ‘endangered’ under the United States’ Endangered Species Act (ESA). There is little information about the sensitivity of Branchinecta spp. to toxic effects of contaminants, making it difficult to determine whether they are adequately protected by water quality criteria. A series of acute (24 hr) lethality/immobilization tests were conducted with three species of fairy shrimp (Branchinecta lynchi, Branchinecta lindahli, and Thamnocephalus platyurus) and 10 chemicals with varying modes of toxic action: ammonia, potassium, chloride, sulfate, chromium(VI), copper, nickel, zinc,...
Design and Development of a Prototype Tool for Integrated Climate Downscaling and Streamflow Prediction using Open Source GIS Software
Tables supporting optimization of on-line hydrogen stable isotope-ratio measurements of halogen- and sulfur-bearing organic compounds using elemental analyzer-chromium/high-temperature conversion-isotope-ratio mass spectrometry
Tabular data demonstrates the performance of a modified reactor setup that enables high-quality hydrogen isotopic analysis of halogen- and sulfur-bearing organics with a modified elemental analyzer–chromium/high temperature conversion reactor that demonstrated an overall hydrogen-recovery of higher than 96 percent. These data support the article by Matthias Gehre, Julian Renpenning, Heike Geilmann, Haiping Qi, Tyler B. Coplen, Steffen Kümmel, Natalija Ivdra, Willi A. Brand, and Arndt Schimmelmann titled "Optimization of on-line hydrogen stable isotope-ratio measurements of halogen- and sulfur-bearing organic compounds using elemental analyzer-chromium/high-temperature conversion-isotope-ratio mass spectrometry (EA–Cr/HTC–IRMS)"...
Variability of mercury concentrations among whole bird feathers, feather homogenates, and feather components quantified in California in 2017-2018
These data are the raw total mercury (THg) concentrations in whole feathers, feather homogenates, and feather components (i.e., rachis, vane, calamus) that are presented in the Journal Article "Mercury concentrations vary within and among individual bird feathers: A critical evaluation and guidelines for feather use in mercury monitoring programs" in Environmental Toxicology and Chemistry by Peterson et al.
Using an inter-lab study to revise methods for conduction 10- to 42-d water or sediment toxicity tests with Hyalella azteca
Studies have been conducted to refine USEPA, ASTM, and Environment Canada standard methods for conducting 42-d reproduction tests with H. azteca in water or in sediment. Modifications to the H. azteca method include better defined ionic composition requirements for exposure water (i.e., >15 mg/L of chloride and >0.02 mg/L of bromide) and improved survival, growth and reproduction with alternate diets provided as increased rations over time in water-only or whole-sediment toxicity tests. A total of 24 laboratories volunteered to participate in an inter-laboratory study evaluating the performance of H. azteca in 42-d studies in control sand or control sediment using the refined methods. Improved growth and reproduction...
Tables and charts for isotope-abundance variations and atomic weights of selected elements: 2016 (Ver. 1.1, May 2018)
Twelve chemical elements have intervals for their standard atomic weights, namely hydrogen, lithium, boron, carbon, nitrogen, oxygen, magnesium, silicon, sulfur, chlorine, bromine and thallium. Isotopic abundances, isotope-delta values, and atomic weights for each of the lower and upper bounds of materials and compounds of these 12 elements are tabulated. Version 1.1 is the most current version.
The total concentration of dissolved constituents in water is routinely quantified by measurements of salinity or total dissolved solids (TDS). However, salinity and TDS are operationally defined by their analytical methods and are not equivalent for most waters. Furthermore, multiple methods are available to determine salinity and TDS, and these methods have inherent differences. TDS is defined as the mass of anhydrous residue remaining in a sample vessel after evaporation and subsequent oven drying at a defined temperature. Salinity is a measure of the mass of dissolved salts in a given mass of solution. In addition, there are approaches that quantify the total solute (TS) concentration, including gases. PHREECI...
Standard atomic weights of the elements 2015
Four-figure standard atomic weights of the chemical elements are shown for 1961, 1975, 1983, 2007, 2009, 2011, 2013, 2015, and the current value for 2016. Values between 1975 and 2015 are only shown when there is a change in value with respect to the previous column.
This dataset is intended to assess trends and percent change per year (PCPY) in yearly averages of turbidity in Florida, summarized to HUC 12 watershed. Assessments (condition) was classified depending on the following follow thresholds for PCPY: <= -1.0% - “Decreasing” > -1.0 & < 0.0% - “Stable (-)” = 0.0% - “Stable (No Change)” > 0.0 & < 1.0% - “Stable (+)” >= 1.0% - “Increasing”