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Book
xix, 416 pages : illustrations (some color) ; 24 cm
Analytical Applications of Ionic Liquids reviews the current research in analytic chemistry, covering subjects as diverse as separation science, chromatography, spectroscopy and analytical electrochemistry.As scientific developments have moved into the 21st century, they have increasingly had to take into account the effects on the environment, both locally and globally. Ionic liquids promise entirely new methods for solution chemistry which could improve the quality of measurements and eliminate the negative impact of waste on the environment. Because of this, the search for applications of ionic liquids is growing in every area of analytical chemistry. Here, material is presented by specialists, giving a critical overview of the current literature surrounding this increasingly prominent topic. Analysis is carried out on latest achievements and applications, followed by critical discussion of possible future developments.As well as stimulating further research among established analytical chemists, this book can also be used for undergraduate and graduate courses on chemistry and chemical technology.
(source: Nielsen Book Data)9781786340719 20161219
Science Library (Li and Ma)
Book
x, 383 pages : illustrations ; 25 cm
  • List of Abbreviations VII Symbols IX 1 What is Chemometrics? 1 1.1 The Computer-Based Laboratory 2 1.2 Statistics and Data Interpretation 10 1.3 Computer-Based Information Systems/Artificial Intelligence 11 General Reading 12 Questions and Problems 13 2 Basic Statistics 15 2.1 Descriptive Statistics 16 2.2 Statistical Tests 28 2.3 Analysis of Variance 44 General Reading 50 Questions and Problems 52 3 Signal Processing and Time Series Analysis 55 3.1 Signal Processing 56 3.2 Time Series Analysis 83 General Reading 90 Questions and Problems 91 4 Optimization and Experimental Design 93 4.1 Systematic Optimization 94 4.2 Objective Functions and Factors 95 4.3 Experimental Design and Response Surface Methods 102 4.4 Sequential Optimization: Simplex Method 125 General Reading 132 Questions and Problems 133 5 Pattern Recognition and Classification 135 5.1 Preprocessing of Data 137 5.2 Unsupervised Methods 140 5.3 Supervised Methods 184 General Reading 209 Questions and Problems 210 6 Modeling 213 6.1 Univariate Linear Regression 214 6.2 Multiple Linear Regression 231 6.3 Nonlinear Methods 258 General Reading 269 Questions and Problems 271 7 Analytical Databases 273 7.1 Representation of Analytical Information 274 7.2 Library Search 286 7.3 Simulation of Spectra 292 General Reading 294 Questions and Problems 295 8 Knowledge Processing and Soft Computing 297 8.1 Artificial Intelligence and Expert Systems 297 8.2 Neural Networks 306 8.3 Fuzzy Theory 321 8.4 Genetic Algorithms and Other Global Search Strategies 334 General Reading 342 Questions and Problems 344 9 Quality Assurance and Good Laboratory Practice 345 9.1 Validation and Quality Control 346 9.2 Accreditation and Good Laboratory Practice 351 General Reading 352 Questions and Problems 353 Appendix 355 Index 371.
  • (source: Nielsen Book Data)9783527340972 20170220
The third edition of this long-selling introductory textbook and ready reference covers all pertinent topics, from basic statistics via modeling and databases right up to the latest regulatory issues. The experienced and internationally recognized author, Matthias Otto, introduces the statistical-mathematical evaluation of chemical measurements, especially analytical ones, going on to provide a modern approach to signal processing, designing and optimizing experiments, pattern recognition and classification, as well as modeling simple and nonlinear relationships. Analytical databases are equally covered as are applications of multiway analysis, artificial intelligence, fuzzy theory, neural networks, and genetic algorithms. The new edition has 10% new content to cover such recent developments as orthogonal signal correction and new data exchange formats, tree based classification and regression, independent component analysis, ensemble methods and neuro-fuzzy systems. It still retains, however, the proven features from previous editions: worked examples, questions and problems, additional information and brief explanations in the margin.
(source: Nielsen Book Data)9783527340972 20170220
Science Library (Li and Ma)

3. Nanobiosensors [2017]

Book
1 online resource.
Nanobiosensors: Nanotechnology in the Agri-Food Industry, Volume 8, provides the latest information on the increasing demand for robust, rapid, inexpensive, and safe alternative technologies that monitor, test, and detect harmful or potentially dangerous foods. Due to their high sensitivity and selectivity, nanobiosensors have attracted attention for their use in monitoring not only biological contaminants in food, but also potential chemical and physical hazards. This book offers a broad overview regarding the current progress made in the field of nanosensors, including cutting-edge technological progress and the impact of these devices on the food industry. Special attention is given to the detection of microbial contaminants and harmful metabolotes, such as toxins and hormones, which have a great impact on both humans and animal health and feed.
Book
1 online resource (600 pages) : illustrations.
  • 1. Start of the Implementation of a New HPLC Method 2. Short Overviews of Analytical Techniques Not Containing an Independent Separation Step 3. Short Overviews of the Main Analytical Techniques Containing a Separation Step 4. Basic Information Regarding the HPLC Techniques 5. Properties of Analytes and Matrices Determining HPLC Selection 6. General Aspects Regarding the HPLC Analytical Column 7. RP-HPLC Analytical Columns 8. Polar Analytical Columns 9. Stationary Phases and Columns for Ion Exchange, Ion-Moderated, and Ligand Exchange Chromatography 10. Stationary Phases and Columns for Chiral Chromatography 11. Stationary Phases and Columns for Size Exclusion 12. Stationary Phases and Columns for Immunoaffinity Type Separations 13. Solvents, Buffers, and Additives Used in the Mobile Phase 14. Gradient Elution 15. The Practice of HPLC.
  • (source: Nielsen Book Data)9780128036846 20170313
Selection of the HPLC Method in Chemical Analysis serves as a practical guide to users of high-performance liquid chromatography and provides criteria for method selection, development, and validation. High-performance liquid chromatography (HPLC) is the most common analytical technique currently practiced in chemistry. However, the process of finding the appropriate information for a particular analytical project requires significant effort and pre-existent knowledge in the field. Further, sorting through the wealth of published data and literature takes both time and effort away from the critical aspects of HPLC method selection. For the first time, a systematic approach for sorting through the available information and reviewing critically the up-to-date progress in HPLC for selecting a specific analysis is available in a single book. Selection of the HPLC Method in Chemical Analysis is an inclusive go-to reference for HPLC method selection, development, and validation.
(source: Nielsen Book Data)9780128036846 20170313
Book
1 online resource.
Shale oil and gas have altered the energy landscape, possibly permanently. They burst upon the fossil energy scene with a suddenness that initially defied prediction. Even the political balance of the world has changed. But, with the methods employed, the vast majority of the oil and gas remains in the ground. At the same time, serious environmental impact issues have been raised. A new volume in the Emerging Issues in Analytical Chemistry series, Sustainable Shale Oil and Gas Production: Analytical, Biochemical, and Geochemical Methods was written on the premise that analytical methods to inform these areas were wanting. While not attempting to be comprehensive, it describes important analytical methods, some still in development. These methods are underpinned primarily by chemistry, but geochemistry and even biochemistry play significant roles. The book has a solutions flavor; problems are posed together with approaches to ameliorate them.
Book
1 online resource (778 pages)
  • How To Use This Book-- What is a CDS and its Evolution-- Laboratory Informatics and the Role of a CDS-- Applicable GXP Regulations and Guidance-- Concepts of Computer Validation-- Understanding Life Cycles and SW Classification-- CDS Data Integrity-- CSV Risk Management: System Risk-- Working Electronically-- Specifying User and System Requirements-- Controlling the Validation-- System Selection-- Auditing the Supplier-- Negotiating the Contract and System Purchase-- Planning the Installation-- CSV Risk Management-- Importance of the Traceability Matrix-- Writing the Configuration Specification-- Writing the Technical Specification-- Installing and Integrating System Components-- Designing the Test Suite-- Writing Test Cases-- Executing Test Scripts-- User Training and System Documentation-- IT Support-- System Description-- Defining CDS Raw Data and E-Records-- Validation Summary Report-- Integration in a Regulated Environment-- User Account Management-- Incident and Problem Management-- Change Control and Configuration Management-- On-Going IT Support-- Conducting a Periodic Review-- CDS Records Retention-- System Retirement-- Data Migration Options-- Retrospective Validation.
  • (source: Nielsen Book Data)9781849736626 20170213
Guiding chromatographers working in regulated industries and helping them to validate their chromatography data systems to meet data integrity, business and regulatory needs. This book is a detailed look at the life cycle and documented evidence required to ensure a system is fit for purpose throughout the lifecycle. Initially providing the regulatory, data integrity and system life cycle requirements for computerised system validation, the book then develops into a guide on planning, specifying, managing risk, configuring and testing a chromatography data system before release. This is followed by operational aspects such as training, integration and IT support and finally retirement. All areas are discussed in detail with case studies and practical examples provided as appropriate. The book has been carefully written and is right up to date including recently released FDA data integrity guidance. It provides detailed guidance on good practice and expands on the first edition making it an invaluable addition to a chromatographer's book shelf.
(source: Nielsen Book Data)9781849736626 20170213
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 (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.
  • Employing 'second generation' matrices.- (MA)LDI MS mass spectrometry imaging at high specificity and sensitivity.- Techniques for fingermark analysis using MALDI MS - a practical overview.- Whole/Intact Cell MALDI MS Biotyping in Mammalian Cell Analyis.- MALDI biotyping for microorganism identification in clinical microbiology.- Future applications of MALDI-TOF MS in microbiology.- MALDESI: Fundamentals, direct analysis, and MS imaging.- Microprobe MS Imaging of Live Tissues, Cells, and Bacterial Colonies using LAESI.- Efficient production of multiply charged MALDI ions.- Food Authentication by MALDI MS - MALDI-TOF MS Analysis of Fish Species.- Quantitative MALDI MS using Ionic Liquid Matrices.- Disease profiling by MALDI MS analysis of biofluids.- Ionic Liquids and other liquid matrices for sensitive MALDI MS analysis.- Coupling liquid MALDI MS to liquid chromatography.
  • (source: Nielsen Book Data)9783319048185 20160619
This book covers the state-of-the-art of modern MALDI (matrix-assisted laser desorption/ionization) and its applications. New applications and improvements in the MALDI field such as biotyping, clinical diagnosis, forensic imaging, and ESI-like ion production are covered in detail. Additional topics include MS imaging, biotyping/speciation and large-scale, high-speed MS sample profiling, new methods based on MALDI or MALDI-like sample preparations, and the advantages of ESI to MALDI MS analysis. This is an ideal book for graduate students and researchers in the field of bioanalytical sciences. This book also: * Showcases new techniques and applications in MALDI MS * Demonstrates how MALDI is preferable to ESI (electrospray ionization) * Illustrates the pros and cons associated with biomarker discovery studies in clinical proteomics and the various application areas, such as cancer proteomics.
(source: Nielsen Book Data)9783319048185 20160619
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.

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