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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
1 online resource (11 p. ) : digital, PDF file.
This is a Laboratory Analytical Procedure (LAP) for bio-oil analysis.
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.
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 (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
1 online resource (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.
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. 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
The invention provides methods and compositions useful for synthesizing alkylaromatics from an n-alkanes.
Book
1 online resource : illustrations (some color).
  • Wonders of Water
  • Water Structure
  • O:H-O Bond Cooperativity
  • Phase Diagram: Bonding Dynamics
  • O:H-O Bond Asymmetrical Potentials
  • Mechanical Compression
  • Thermal Excitation
  • Molecular Undercoordination: Supersolidity
  • Superlubricity of Ice
  • Water Supersolid Skin
  • Mpemba Paradox
  • Aqueous Solution Point Controllers
  • Hydration Shells versus Water Skin
  • Aqueous Solution Phase Transition
  • Water Floating Bridge
  • Miscellaneous Issues
  • Approaching Strategies
  • Laws for Water.
This book features the latest advances and future trends in water science and technology. It also discusses the scientific popularization and quantitative resolution of a variety of mysterious properties of water and ice from the perspective of hydrogen-bond cooperativity in response to stimuli such as chemical contamination, electrification, magnetification, mechanical compression, molecular undercoordination, and thermal excitation. Anomalies include the floating of ice, the Hofmeister effect in solutions, regelation of ice, slipperiness of ice, water's tough skin, the Mpemba paradox, and the floating bridge. It also addresses the superfluidity of microchannels, hydrogen bond potentials, nanodroplet and bubble thermodynamics, quasisolidity and supersolidity, controlling superhydrophobicity-superhydrophilicity transition, and high-pressure ice formation. The target audience for this book includes students, senior scholars, engineers and practitioners in the area of physical chemistry, biology, as well as aqueous and colloid solutions.
Compound of Formula I: are described, along with compositions containing the same and methods of use thereof. ##STR00001##
Book
1 online resource (p. 1474-1486 ) : digital, PDF file.
Lignocellulosic biorefineries will produce a substantial pool of lignin-enriched residues, which are currently slated to be burned for heat and power. Going forward, however, valorization strategies for residual solid lignin will be essential to the economic viability of modern biorefineries. To achieve these strategies, effective lignin depolymerization processes will be required that can convert specific lignin-enriched biorefinery substrates into products of sufficient value and market size. Base-catalyzed depolymerization (BCD) of lignin using sodium hydroxide and other basic media has been shown to be an effective depolymerization approach when using technical and isolated lignins relevant to the pulp and paper industry. Moreover, to gain insights in the application of BCD to lignin-rich, biofuels-relevant residues, here we apply BCD with sodium hydroxide at two catalyst loadings and temperatures of 270, 300, and 330 °C for 40 min to residual biomass from typical and emerging biochemical conversion processes. We obtained mass balances for each fraction from BCD, and characterized the resulting aqueous and solid residues using gel permeation chromatography, NMR, and GC–MS. When taken together, these results indicate that a significant fraction (45–78%) of the starting lignin-rich material can be depolymerized to low molecular weight, water-soluble species. The yield of the aqueous soluble fraction depends significantly on biomass processing method used prior to BCD. Namely, dilute acid pretreatment results in lower water-soluble yields compared to biomass processing that involves no acid pretreatment. We also find that the BCD product selectivity can be tuned with temperature to give higher yields of methoxyphenols at lower temperature, and a higher relative content of benzenediols with a greater extent of alkylation on the aromatic rings at higher temperature. Our study shows that residual, lignin-rich biomass produced from conventional and emerging biochemical conversion processes can be depolymerized with sodium hydroxide to produce significant yields of low molecular weight aromatics that potentially can be upgraded to fuels or chemicals.
A novel electron acceptor based on bay-annulated indigo (BAI) was synthesized and used for the preparation of a series of high performance donor-acceptor small molecules and polymers. The resulting materials possess low-lying LUMO energy level and small HOMO-LUMO gaps, while their films exhibited high crystallinity upon thermal treatment, commensurate with high field effect mobilities and ambipolar transfer characteristics.
Book
1 online resource (p. 2162-2170 ) : digital, PDF file.

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