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Book
17 p. : digital, PDF file.
Despite decades of research on the reactivity and stable isotope properties of Fe oxides, the ability to describe the redox behavior of Fe oxides in the environment is still quite limited. This is due, in large part, to the analytical and spatial complexities associated with studying microscopic processes at the Fe oxide-water interface. This project had the long-term vision of filling this gap by developing a detailed understanding of the relationship between interfacial ET processes, surface structure and charge, and mineral semiconducting properties. We focused on the Fe(III)-oxides and oxyhydroxides because of their geochemical preponderance, versatility in synthesis of compositionally, structurally, and morphologically tailored phases, and because they are amenable to a wide range of surface and bulk properties characterization. In particular, reductive transformation of phases such as hematite (α-Fe<sub>2</sub>O<sub>3</sub>) and goethite (α-FeOOH) in aqueous solution can serve as excellent model systems for studies of electron conduction processes, as well as provide valuable insights into effect of nanoscale conductive materials on contaminant fate at DOE sites. More specifically, the goal of the Iowa component of this project was to use stable Fe isotope measurements to simultaneously measure isotope specific oxidation states and concentrations of Fe at the hematite-water and goethite-water interface. This work builds on our previous work where we used an innovative combination of <sup>57</sup>Fe Mössbauer spectroscopy and high precision isotope ratio measurements (MC-ICP-MS) to probe the dynamics of the reaction of aqueous Fe(II) with goethite. Mössbauer spectroscopy detects <sup>57</sup>Fe only among all other Fe isotopes and we have capitalized on this to spectroscopically demonstrate Fe(II)-Fe(III) electron transfer between sorbed Fe(II) and Fe(III) oxides (Handler, et al., 2009; Gorski, et al. 2010; Rosso et al., 2010). By combining the Mössbauer spectroscopy and stable isotopes measurements, we have been able to simultaneously track the oxidation state and isotope concentration of the bulk Fe oxide and aqueous Fe. One of our most compelling findings is that despite the apparent stability of the Fe(II)-goethite system, there is actually a tremendous amount of Fe atom cycling occurring between the aqueous phase and the bulk goethite as indicated by the isotopic composition of both phases approaching the mass balance average (Handler et al., 2009). How such extensive re-crystallization and Fe atom exchange can occur with no significant morphological change is a fascinating question. Based on previous work from PI Rosso’s group showing that a potential gradient across hematite crystal faces leads to conduction through hematite and growth and dissolution at separate crystal faces we proposed that a redox-driven recrystallization could be occurring that would explain the extensive mixing observed with the isotope data. From our previous studies utilizing Mössbauer spectroscopy, we know that sorption of Fe(II) onto goethite results in electron transfer between the sorbed Fe(II) and the structural Fe(III) in goethite. Oxidation of the sorbed Fe(II) produces growth of goethite on goethite (i.e., homoepitaxy), as well as injection of an electron into goethite. It is possible that electron transfer from sorbed Fe(II) occurs across a potential gradient, and that Fe(II) atoms are dissolved at a different location on the goethite surface. These newly-reduced Fe(II) atoms could then dissolve into the aqueous phase, exposing fresh Fe(III) goethite to the aqueous phase. Through a repeated series of these five steps of sorption–electron transfer–crystal growth–conduction– dissolution, a redox-driven conveyor belt, could be established that would allow all of the goethite to be eventually exposed to the aqueous phase and exchanged. This surface-mediated recrystallization process would result in similar Fe isotope distributions i...
Book
1 online resource (p. 2825–2831 ) : digital, PDF file.
<sup>13</sup>C-Metabolic Flux Analysis (<sup>13</sup>C-MFA) is rapidly being recognized as the authoritative method for determining fluxes through metabolic networks. Site-specific <sup>13</sup>C enrichment information obtained using NMR spectroscopy is a valuable input for <sup>13</sup>C-MFA experiments. Chemical shift overlaps in the 1D or 2D NMR experiments typically used for <sup>13</sup>C-MFA frequently hinder assignment and quantitation of site-specific <sup>13</sup>C enrichment. Here we propose the use of a 3D TOCSY-HSQC experiment for <sup>13</sup>C-MFA. We employ Non-Uniform Sampling (NUS) to reduce the acquisition time of the experiment to a few hours, making it practical for use in <sup>13</sup>C-MFA experiments. Our data show that the NUS experiment is linear and quantitative. Identification of metabolites in complex mixtures, such as a biomass hydrolysate, is simplified by virtue of the <sup>13</sup>C chemical shift obtained in the experiment. In addition, the experiment reports <sup>13</sup>C-labeling information that reveals the position specific labeling of subsets of isotopomers. As a result, the information provided by this technique will enable more accurate estimation of metabolic fluxes in larger metabolic networks.
Book
9 p. : digital, PDF file.
<p>We report here the synthesis of a neutral viologen derivative, C<sub>24</sub>H<sub>16</sub>N<sub>2</sub>O<sub>4</sub>·2H<sub>2 </sub>O. The non-solvent portion of the structure (<italic>Z</italic>-Lig) is a zwitterion, consisting of two positively charged pyridinium cations and two negatively charged carboxylate anions. The carboxylate group is almost coplanar [dihedral angle = 2.04 (11)°] with the benzene ring, whereas the dihedral angle between pyridine and benzene rings is 46.28 (5)°. The<italic>Z</italic>-Lig molecule is positioned on a center of inversion (Fig. 1). The presence of the twofold axis perpendicular to the<italic>c</italic>-glide plane in space group<italic>C</italic>2/c generates a screw-axis parallel to the<italic>b</italic>axis that is shifted from the origin by 1/4 in the<bold>a</bold>and<bold>c</bold>directions. This screw-axis replicates the molecule (and solvent water molecules) through space. The<italic>Z</italic>-Lig molecule links to adjacent molecules<italic>via</italic>O—H...O hydrogen bonds involving solvent water molecules as well as intermolecular C—H...O interactions. There are also π–π interactions between benzene rings on adjacent molecules.</p>
Book
1 online resource (11 p. ) : digital, PDF file.
This is a Laboratory Analytical Procedure (LAP) for bio-oil analysis.
Book
1 online resource.
An acid-functionalized polyolefin material that can be used as an acid catalyst in a wide range of acid-promoted chemical reactions, wherein the acid-functionalized polyolefin material includes a polyolefin backbone on which acid groups are appended. Also described is a method for the preparation of the acid catalyst in which a precursor polyolefin is subjected to ionizing radiation (e.g., electron beam irradiation) of sufficient power and the irradiated precursor polyolefin reacted with at least one vinyl monomer having an acid group thereon. Further described is a method for conducting an acid-promoted chemical reaction, wherein an acid-reactive organic precursor is contacted in liquid form with a solid heterogeneous acid catalyst comprising a polyolefin backbone of at least 1 micron in one dimension and having carboxylic acid groups and either sulfonic acid or phosphoric acid groups appended thereto.
Book
1 online resource (9 p. ) : digital, PDF file.
The ACS Division of Nuclear Chemistry and Technology was initiated in 1955 as a subdivision of the Division of Industrial and Engineering Chemistry. Probationary divisional status was lifted in 1965. The Division’s first symposium was held in Denver in 1964 and it is fitting that we kicked-off the 50th Anniversary in Denver in the spring of 2015. Listed as a small ACS Division with only about 1,000 members, NUCL’s impact over the past fifty years has been remarkable. National ACS meetings have had many symposia sponsored or cosponsored by NUCL that included Nobel Laureates, U.S. Senators, other high-ranking officials and many students as speakers. The range of subjects has been exceptional as are the various prestigious awards established by the Division. Of major impact has been the past 30 years of the NUCL Nuclear Chemistry Summer Schools to help fill the void of qualified nuclear scientists and technicians. In celebrating the 50th Anniversary we honor the past, celebrate the present and shape the future of the Division and nuclear science and technology. To celebrate this auspicious occasion a commemorative lapel pin has been designed for distribution to NUCL Division members.
Book
1 online resource (12 p. ) : digital, PDF file.
In this study, the Fischer-Tropsch synthesis (FTS) reaction is one of the most promising processes to convert alternative energy sources, such as natural gas, coal or biomass, into liquid fuels and other high-value products. Despite its commercial implementation, we still lack fundamental insights into the various deactivation processes taking place during FTS. In this work, a combination of three methods for studying single catalyst particles at different length scales has been developed and applied to study the deactivation of Co/TiO<sub>2</sub> Fischer-Tropsch synthesis (FTS) catalysts. By combining transmission X-ray microscopy (TXM), scanning transmission X-ray microscopy (STXM) and scanning transmission electron microscopy-electron energy loss spectroscopy (STEM-EELS) we visualized changes in the structure, aggregate size and distribution of supported Co nanoparticles that occur during FTS. At the microscale, Co nanoparticle aggregates are transported over several μm leading to a more homogeneous Co distribution, while at the nanoscale Co forms a thin layer of ~1-2 nm around the TiO<sub>2</sub> support. The formation of the Co layer is the opposite case to the “classical” strong metal-support interaction (SMSI) in which TiO<sub>2</sub> surrounds the Co, and is possibly related to the surface oxidation of Co metal nanoparticles in combination with coke formation. In other words, the observed migration and formation of a thin CoO<sub>x</sub> layer are similar to a previously discussed reaction-induced spreading of metal oxides across a TiO<sub>2</sub> surface.
Book
1 online resource.
  • Preface; Contents; 1 Introduction; 1.1 Preamble; 1.1.1 History of Manufacture of Sulphuric Acid in India; 1.1.2 History of Manufacture of Sulphuric Acid; 1.1.2.1 Sulphuric Acid Manufacture has Flourished Since the Mid-19th Century; 1.1.3 Salient Features of the Modified (3 + 2) DCDA Process; 2 Chemical and Physical Properties of Sulphur Dioxide and Sulphur Trioxide; 2.1 Introduction; 2.2 Sulphur Dioxide Physical Properties; 2.3 Vaporisation of SO2; 2.4 The Solubility of SO2 in Sulphuric Acid; 2.5 Solubility of Sulphur Dioxide in Water; 2.6 Chemical Properties of Sulphur Dioxide
  • 2.7 Physical Properties of Sulphur Trioxide2.8 General Properties of Liquid Sulphur Trioxide; 2.9 Properties of Liquid Sulphur Trioxide; 2.10 Viscosity of Liquid Sulphur Trioxide; 2.11 Specific Gravity of Sulphur Trioxide; 2.12 Vapour Pressure of Liquid Sulphur Trioxide; 2.13 Molar Heat Capacity of Liquid Sulphur Trioxide; 2.14 Vaporisation Curves for Sulphur Dioxide; 2.15 Enthalpy of Sulphur Trioxide Gas; 2.16 Chemical Properties of Sulphur Trioxide
  • 2.16.1 Commercially Sulphur Trioxide Is Produced by Converting 10
  • 12 % SO2 by Catalytic Conversion at Temperatures Between 360
  • 600 ̊C in Multipass Converter of Sulphuric Acid Plant2.17 One of the Special Chemical Properties of SO3 Which Has Been Safer but not Explored till date; 2.18 Sulphur Trioxide Is a Strong Sulphonating Agent for Difficult, Organic and Inorganic Chemicals; 2.18.1 Treatment of Sulphuric Acid Plant Tail Gas from Final Absorption Tower; 3 Manufacture of Sulphonating Agents Such as 25 and 65 % Oleums as well as Liquid Sulphur Trioxide; 3.1 Introduction
  • 3.2 Production of 25 % Oleum3.2.1 History; 3.3 Technical Considerations; 3.4 Manufacturing; 3.5 65 % Oleum; 3.5.1 Introduction; 3.6 Manufacturing; 3.7 Uses; 3.8 Sulphur Trioxide (Liquid or Gas); 3.8.1 Introduction; 3.9 Manufacture; 3.10 Economic Considerations; 4 Manufacture of Liquid Sulphur Dioxide; 4.1 Manufacture of Liquid Sulphur Dioxide; 4.2 Thermodynamic and Kinetic Consideration of the NEAT's Process; 4.3 International Scenario; 4.4 Merchant Market for SO2 in Various for Many Industrial Applications; 4.5 Process Description; 4.6 Operational Considerations
  • 4.6.1 Condensation and Filling Section4.7 Economics; 4.8 Environmental Considerations; 4.9 Conclusion; 5 World Production of Liquid SO2 and SO3; 5.1 Introduction; 5.2 World Scenario; 5.2.1 Comparative Analysis on Techno Economic Considerations; 5.3 Economics of Manufacture of Liquid SO2; 5.4 Economics of Manufacture of Liquid SO3; 5.5 Conclusion; 6 Techno Economic Evaluation of Processes Involved to Manufacture Liquid Sulphur Dioxide and Liquid Sulphur Trioxide; 6.1 Introduction; 6.2 History
This book presents a complete, in-depth analysis for on the impact of liquid sulfur dioxide and liquid sulfur trioxide to carry out complex and difficult sulfonations, as well as manufacture of sulfuric acid with a CAPEX requirement of less than half, an area requirement less than one-third, and no emission of sulfur dioxide. The processes described in this volume represents an innovative approach relevant to the current manufacturing processes of sulfuric acid, sulfamic acid, para toluene sulfonic acid and other sulfonated product.
The current invention describes methods and compositions of various sorbents based on aerogels of various silanes and their use as sorbent for carbon dioxide. Methods further provide for optimizing the compositions to increase the stability of the sorbents for prolonged use as carbon dioxide capture matrices.
Book
1 online resource.
Systems for converting aldose sugars to ketose sugars and separating and/or concentrating these sugars using differences in the sugars' abilities to bind to specific affinity ligands are described.
Book
1 online resource (3 p. ) : digital, PDF file.
This report documents a Pu isotopic analysis.
Book
1 online resource.
Provided in one embodiment is an electrochemical cell, comprising: (i) a plurality of electrodes, comprising a fuel electrode that comprises aluminum and an air electrode that absorbs gaseous oxygen, the electrodes being operable in a discharge mode wherein the aluminum is oxidized at the fuel electrode and oxygen is reduced at the air electrode, and (ii) an ionically conductive medium, comprising an organic solvent; wherein during non-use of the cell, the organic solvent promotes formation of a protective interface between the aluminum of the fuel electrode and the ionically conductive medium, and wherein at an onset of the discharge mode, at least some of the protective interface is removed from the aluminum to thereafter permit oxidation of the aluminum during the discharge mode.
Book
1 online resource (15 p. ) : digital, PDF file.
The degradation of Antifoam 747 to form flammable decomposition products has resulted in declaration of a Potential Inadequacy in the Safety Analysis (PISA) for the Defense Waste Processing Facility (DWPF). Savannah River National Laboratory (SRNL) testing with simulants showed that hexamethyldisiloxane (HMDSO), trimethylsilanol (TMS), and 1-propanal are formed in the offgas from the decomposition of the antifoam. A total of ten DWPF condensate samples from Batch 735 and 736 were analyzed by SRNL for three degradation products and additional analytes. All of the samples were analyzed to determine the concentrations of HMDSO, TMS, and propanal. The results of the organic analysis found concentrations for propanal and HMDSO near or below the detection limits for the analysis. The TMS concentrations ranged from below detection to 11 mg/L. The samples from Batch 736 were also analyzed for formate and oxalate anions, total organic carbon, and aluminum, iron, manganese, and silicon. Most of the samples contained low levels of formate and therefore low levels of organic carbon. These two values for each sample show reasonable agreement in most cases. Low levels of all the metals (Al, Fe, Mn, and Si) were present in most of the samples.
Book
1 online resource (26 p. ) : digital, PDF file.
The Bioenergy Program at Pacific Northwest National Laboratory (PNNL) is evaluating the feasibility of converting wastewater sludge materials to fuels. Wastewater sludge from various municipalities will be used in the evaluation process and as with any municipal waste, there is the potential for residual contaminates to remain in the sludge following wastewater treatment. Many surveys and studies have confirmed the presence of pharmaceuticals in municipal wastewater and effluents (World Health Organization, 2011). Determination of the presence and concentrations of the contaminants is required to define the proper handling of this sludge. A list of targeted compounds was acquired from the literature and an analytical method was developed for the pharmaceutical and personal care compounds. The presence of organics complicated the analytical techniques and, in some cases, the precision of the results. However, residual concentrations of a range of compounds were detected in the wastewater sludge and the presence and concentrations of these compounds will be considered in identifying the appropriate handling of this material in conduct of research.
Book
1 online resource (9 p. ) : digital, PDF file.
LANL has been contacted to provide possible assistance in safe disposition of a number of <sup>241</sup>Am-bearing materials associated with local industrial operations. Among the materials are ion exchange resins which have been in contact with <sup>241</sup>Am and nitric acid, and which might have potential for exothermic reaction. The purpose of this paper is to analyze and define the resin forms and quantities to the extent possible from available data to allow better bounding of the potential reactivity hazard of the resin materials. An additional purpose is to recommend handling procedures to minimize the probability of an uncontrolled exothermic reaction.
Book
16 p. : digital, PDF file.
Savannah River National Laboratory analyzed samples from Tank 38H and Tank 43H to support Enrichment Control Program and Corrosion Control Program. The total uranium in the Tank 38H samples ranged from 20.5 to 34.0 mg/L while the Tank 43H samples ranged from 47.6 to 50.6 mg/L. The U-235 percentage ranged from 0.62% to 0.64% over the four samples. The total uranium and percent U-235 results appear consistent with previous Tank 38H and Tank 43H uranium measurements. The Tank 38H plutonium results show a large difference between the surface and sub-surface sample concentrations and a somewhat higher concentration than previous sub-surface samples. The two Tank 43H samples show similar plutonium concentrations and are within the range of values measured on previous samples. The plutonium results may be biased high due to the presence of plutonium contamination in the blank samples from the cell sample preparations. The four samples analyzed show silicon concentrations ranging from 47.9 to 105 mg/L.
Book
Article No. 21660 : digital, PDF file.
Within the BaFe<sub>2</sub>As<sub>2</sub> crystal lattice, we partially substitute thallium for barium and report the effects of interlayer coupling in Ba<sub>1-x</sub>Tl<sub>x</sub>Fe<sub>2</sub>As<sub>2</sub> crystals. We demonstrate the unusual effects of magneto-elastic coupling and charge doping in this iron-arsenide material, whereby Néel temperature rises with small x, and then falls with additional x. Specifically, we find that Néel and structural transitions in BaFe<sub>2</sub>As<sub>2</sub> (TN = T<sub>s</sub> = 133 K) increase for x = 0.05 (T<sub>N</sub> = 138 K, T<sub>s</sub> = 140 K) from magnetization, heat capacity, resistivity, and neutron diffraction measurements. Evidence from single crystal X-ray diffraction and first principles calculations attributes the stronger magnetism in x = 0.05 to magneto-elastic coupling related to the shorter intraplanar Fe-Fe bond distance. With further thallium substitution, the transition temperatures decrease for x = 0.09 (T<sub>N </sub>= T<sub>s</sub> = 131 K), and this is due to charge doping. Finally, we illustrate that small changes related to 3d transition-metal state can have profound effects on magnetism.
Book
1 online resource.
The disclosure discloses abrasion resistant, persistently hydrophobic and oleophobic, anti-reflective and anti-soiling coatings for glass. The coatings described herein have wide application, including for example the front cover glass of solar modules. Methods of applying the coatings using various apparatus are disclosed. Methods for using the coatings in solar energy generation plants to achieve greater energy yield and reduced operations costs are disclosed. Coating materials are formed by combinations of hydrolyzed silane-base precursors through sol-gel processes. Several methods of synthesis and formulation of coating materials are disclosed.
Book
1 online resource.
Disclosed is an exemplary method of purifying lead which includes the steps of placing lead and a fluoride salt blend in a container; forming a first fluid of molten lead at a first temperature; forming a second fluid of the molten fluoride salt blend at a second temperature higher than the first temperature; mixing the first fluid and the second fluid together; separating the two fluids; solidifying the molten fluoride salt blend at a temperature above a melting point of the lead; and removing the molten lead from the container. In certain exemplary methods the molten lead is removed from the container by decanting. In still other exemplary methods the molten salt blend is a Lewis base fluoride eutectic salt blend, and in yet other exemplary methods the molten salt blend contains sodium fluoride, lithium fluoride, and potassium fluoride.
Book
1 online resource. Digital: text file; PDF.
  • Part I Introduction.- Ionic Liquids in the Context of Rare Earth Separation and Utilization.- Part II Chemistry of Ionic Liquids with Rare Earth.- Structural Studies of Rare Earth Salts Isolated From High Ionic Strength Media: The Importance Of Ionicity in Ionic Liquids Separations.- The Coordination Chemistry of Ionic Liquids and Rare Earth.- Solvation Microdynamics and Quantum Chemistry Modeling of Rare Earth in Ionic Liquid by NMR Method.- Part III Ionic Liquids for the Extraction and Separation of Rare Earth.- Actinide and Lanthanide Separations from Rare-Earth Fission Products by Ionic Liquids.- Extraction of Rare-Earth Ions Using Ionic Liquids as Solvent.- Ionic Liquids for Rare Earth Separation.- Part IV Electrodeposition of Rare Earth Metal in Ionic Liquids.- Electrodeposition of Rare Earth Metal in Ionic Liquids.- Part V Ionic Liquids for Rare Earth Utilization.- Ionic Liquids and Rare Earth Soft Photoluminescence Materials.- Preparation of Rare Earth Functional Materials in Ionic Liquids.
  • (source: Nielsen Book Data)9783662475096 20160619
This book comprehensively details the applications of ionic liquids in rare earth green separation and utilization based on the unique interactions of ionic liquids with rare earth ions. It consists of nine chapters demonstrating the synthesis and properties of ionic liquids, coordination chemistry of ionic liquids and rare earth, ionic liquids as diluents, extractants, adsorption resins for rare earth extraction and separation, electrodeposition of rare earth metals in ionic liquids, and preparation of rare earth material with the aid of ionic liquids. It is both interesting and useful to chemists, metallurgists and graduate students working on fundamental research of ionic liquids as well as professionals in the rare earth industry. It provides considerable insights into green chemistry and sustainable processes for rare earth separation in order to meet the environmental challenge of rare earth metallurgy around the globe, especially in China. Ji Chen is a Professor of Chemistry at the Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, China.
(source: Nielsen Book Data)9783662475096 20160619

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