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  • Foreword by George E. Keller, II xi Preface xiii Software Selection and Copyright Notice xvii Acknowledgments xix About the Authors xxi List of Computer Files xxiii 1 Simulation of Adsorption Processes 1 1.1 Introduction to Gas-phase Adsorption Technologies 1 1.2 Core Concepts in Gas Adsorption 2 1.2.1 The Adsorption Process 2 1.2.2 How the Driving Forces Achieve Separation 3 1.3 Isotherms 4 1.3.1 The Langmuir Isotherm (1918) 5 1.3.2 The Linear Isotherm 5 1.3.3 The Brunauer-Emmett-Teller (BET) Isotherm (1938) 5 1.3.4 The Freundlich Isotherm (1906) 6 1.3.5 The Sips (Langmuir-Freundlich) Isotherm (1948) 6 1.3.6 The Toth Isotherm (1971) 6 1.3.7 Summary 6 1.4 The Properties of Packed Beds 6 1.4.1 Void Fractions 7 1.4.2 External Voids 8 1.4.3 Internal Voids 8 1.4.4 Densities 8 Bulk Density 8 Skeletal or Solid Density 9 Envelope or Particle Density 10 Caveats 10 1.4.5 Relationships 10 1.4.6 Gas-phase Behavior 10 Pressure Drop 10 Compressibility 11 1.5 PSA and TSA Implementation Details 12 1.5.1 Common Adsorbent Characteristics 12 1.5.2 Common Process Configurations 12 1.6 Introduction to Aspen Adsorption 13 1.7 PSAWorkshop: Aspen Adsorption Modeling for Air Separation 15 1.7.1 Adding Components to an Aspen Adsorption Simulation 17 1.7.2 Creating a Flowsheet in Aspen Adsorption 22 1.7.3 Specifying Operating Conditions: Tables and Forms 33 1.7.4 Scheduling Events with the Cycle Organizer 42 1.7.5 Running an Aspen Simulation 51 1.7.6 Viewing and Exporting Simulation Results 51 1.8 PSAWorkshop: Hydrogen Separation in Aspen Adsorption 57 1.8.1 Define the Components and Property Model 58 1.8.2 Creating a Flowsheet in Aspen Adsorption 63 1.8.3 Run a Breakthrough Simulation 65 1.8.4 Create the PSA Flowsheet 77 1.9 PSAWorkshop: Modeling Hydrogen Separation using gCSS 87 1.9.1 Define the Components and Property Models 91 1.9.2 Working with Model Libraries: Advanced Flowsheet Options 95 1.9.3 Introduction to Scripting: Set Repeated Values and Initialize Blocks 108 1.9.4 Inspecting Blocks: Advanced Operating Conditions 112 1.9.5 Defining the Cycle Organizer 119 1.9.6 Viewing Results 127 1.10 TSAWorkshop: Temperature Swing Adsorption for Air Drying 128 1.11 Conclusions 140 1.12 Practice Problems 143 1.12.1 Introducing a gas_interaction Unit intoWorkshop 1 143 1.12.2 Naphtha Upgrading Using Adsorption 145 1.13 Nomenclature 149 Bibliography 150 2 Simulation of SMB Chromatographic Processes 155 2.1 Introduction to Chromatography 155 2.1.1 Mathematical Differences from Gas Adsorption 155 The Trace Liquid Assumption 155 Concentration Versus Partial Pressure 156 2.1.2 Thermodynamic Differences from Gas Adsorption 156 Isotherms 156 Physical Property Models 156 2.2 Introduction to SMB Chromatography 156 2.3 SMB Implementation Details 157 2.3.1 Common Process Configurations 157 2.3.2 M-Values 160 2.3.3 Scale-Up Concerns 161 2.3.4 Pressure Drop Limitations 162 2.3.5 Introduction to OperationalModes 163 2.4 SMBWorkshop: Simulate a Four-Zone SMB in Aspen Chromatography for the Separation of Troeger's Base Enantiomers 163 2.4.1 Creating a Flowsheet in Aspen Chromatography 163 2.4.2 Adding Components to an Aspen Chromatography Simulation 164 2.4.3 The Chrom_CCC_separator2 Block 165 2.4.4 Viewing Results 188 2.5 Tandem SMBWorkshop: Simulate a Separation with Dual SMB Columns 192 2.6 Practice Problems 194 2.6.1 RunWorkshop 2.4 as a Steady-State Simulation 194 2.6.2 Simulation of an Industrial-Scale Xylene Separation Using Literature Data 200 2.6.3 Simulate a Five-Zone SMB System for Separating Phenylalanine, Tryptophan, and Methionine 202 Bibliography 206 3 Shortcut Design of SMB Systems 213 3.1 General Concepts 213 3.1.1 Mass Balances 215 3.1.2 Differential Equations 217 3.1.3 The Method of Characteristics 218 3.2 TriangleTheory 219 3.2.1 Notations 219 3.2.2 Introduction 219 3.2.3 Constraints on the System 222 3.3 TriangleTheoryWorkshop: Design of a System for the Separation of Amino Acids 224 3.4 Exercise 1: Calculating Transitions in a Fixed Bed Using Mathematica 230 3.4.1 Differential Equations - Analysis 232 3.4.2 Constructing the Solution from Eigenvectors and Eigenvalues 238 3.4.3 Use the Steady-State Information to Constrain Operating 3.4.4 Calculate the Curves Defined by the Eigenvectors 241 3.4.5 Calculate the Eigenvalues along the Transition 244 3.4.6 Calculate the Concentrations in Time and Space 246 3.4.7 Account for ShockWaves 246 3.5 Exercise 2: Constructing the Constraints on the TMB System in Mathematica 249 3.6 StandingWave Design 253 3.6.1 StandingWave Design in a Nonlinear Ideal System 254 3.6.2 StandingWave Design in a System with Nonlinear Isotherm and Significant Mass Transfer Effects 261 3.7 StandingWave DesignWorkshop: Calculating the Operating Conditions for an Ideal and a Nonideal System 265 3.8 Conclusions 271 3.9 Practice Problems 272 3.9.1 Use the TriangleTheory Tool and the StandingWave Design Tool to Create an Aspen Simulation of the Separation of 1-phenol-1-propanol on Tribenzoate 272 Bibliography 274 4 Operational Modes of SMB Processes 283 4.1 Overview 283 4.2 Selection of OperationalModes 284 4.3 Varicol 284 4.3.1 Design Heuristics and Examples 286 4.3.2 Workshop 1: Apply Varicol to the 4-Zone SMB Model 287 4.4 PowerFeed 293 4.4.1 Design Heuristics and Examples 294 4.4.2 Workshop 2: Apply PowerFeed to the Four-Zone SMB Model 297 4.5 ModiCon 309 4.5.1 Design Heuristics and Examples 309 4.5.2 Workshop 3: Apply ModiCon to the 4-Zone SMB Model 315 4.6 Combined Modes 323 4.6.1 Workshop 4: Extend Previously Created Flowsheets 323 4.7 Parallel Two Zones 330 4.7.1 Introduction to Parallel Two Zones 330 4.7.2 Specification Analysis 334 4.7.3 Importing Flowsheets 337 4.8 Conclusions 345 4.9 Practice Problems 345 4.9.1 Simulation of a Five-Zone SMB Unit Using the ModiCon Operational Mode 345 4.9.2 Compare Parallel Two-Zone Results with SMB Results 345 Bibliography 347 5 Parameter Estimation, Regression, and Sensitivity of Adsorptive and Chromatographic Processes 349 5.1 Empirical Correlations for Physical Properties 349 5.1.1 Axial Dispersion Coefficient 349 5.1.2 Mass Transfer Coefficient 350 5.1.3 Caveats 351 5.2 ParameterWorkshop: Regressing against Steady-State Experiments 351 5.2.1 Introduction to "Experiments" In Aspen Software 351 5.2.2 Experimental Data 352 5.2.3 Parameter Regression in Excel 352 5.2.4 Parameter Regression in Aspen Chromatography 363 Defining an Estimation Flowsheet 363 Entering Experimental Data 364 Estimation Settings 368 Running an Estimation 370 5.2.5 Parameter Regression In Mathematica 370 Defining the Functions 371 Entering the Data 372 Regression 375 5.3 ParameterWorkshop: Regressing Against Dynamic Experiments 376 5.3.1 Problem Description 376 5.3.2 Dynamic Estimation Settings 376 5.3.3 Performance Concerns 380 5.4 Xylene Parameter Regression 380 5.5 Conclusions 386 5.6 Practice Problems 387 5.6.1 Perform Dynamic Parameter Estimation in Aspen Adsorption 387 5.6.2 Sensitivity Analysis Using Scripts in Aspen Adsorption 389 Bibliography 393 Literature Cited in the Text 395 Index 399.
  • (source: Nielsen Book Data)9783527814992 20180618
This book allows the reader to effectively design, simulate and optimize adsorptive and chromatographic separations for industrial applications. To achieve this, a unified approach is presented, which develops the ideal and intermediate equations necessary, while simultaneously offering hands-on case studies employing the rigorous simulation packages Aspen Adsorption and Aspen Chromatography. The first part of the book deals with design strategies, detailed design considerations and the assumptions, which the models are allowed to make and covers shortcut design methods as well as mathematical tools to determine optimal operating conditions. These insights are used in Chapter 4 & 5 to estimate and optimize performance parameters, such as purity, recovery, etc. as well as the regression of these parameters.
(source: Nielsen Book Data)9783527814992 20180618
1 online resource : illustrations
  • Introduction of Mass Spectrometry and Ambient Ionization Techniques / Yiyang Dong, Jiahui Liu, Tianyang Guo
  • DART Mass Spectrometry: Principle and Ionization Facilities / David Rondeau
  • Sampling and Analyte Enrichment Strategies for DART-MS / Wen Ma, Xianjiang Li, Huwei Liu
  • Optimization of DART and Mass Spectrometric Parameters / Guohua Wu, Wushuang Li
  • Interfacing DART to Extend Analytical Capabilities / Yiding Zhang, Shuting Xu, Yu Bai
  • Application of DART-MS in Foods and Agro-Products Analysis / Canping Pan, Lei Wang
  • Application of DART-MS for Industrial Chemical Analysis / Qiang Ma
  • Application of Direct Analysis in Real Time Coupled to Mass Spectrometry (DART-MS) for the Analysis of Environmental Contaminants / Maxime C Bridoux, Sébastien Schramm
  • Application of DART-MS in Clinical and Pharmacological Analysis / Yue Li
  • DART-MS Applications in Pharmaceuticals / Karina G Putri, Qianwen Wu, Young P Jang
  • Application of DART-MS in Natural Phytochemical Research / Vikas Bajpai, Awantika Singh, Brijesh Kumar, Kunnath P Madhusudanan
  • Miscellaneous Applications of DART-MS / Yoshihito Okada
  • Inherent Limitations and Prospects of DART-MS / Tim T Häbe, Matthias Nitsch, Gertrud E Morlock.
DART-MS is a relatively new, but very fast evolving technology. Due to its versatility, it addresses fields of crucial importance to people and community, e.g. food or agricultural, forensic, industrial, environmental, medicinal and clinical analysis.
(source: Nielsen Book Data)9783527803736 20180618
1 online resource (788 pages) : illustrations.
  • 1. Stark-Induced Adiabatic Passage Processes to Selectively Prepare Vibrationally Excited Single and Superposition of Quantum States 2. Advances in Two-Dimensional Correlation Spectroscopy (2DCOS) 3. Applications of 2D-IR Spectroscopy to Probe the Structural Dynamics of DNA 4. Vibrational Potential Energy Surfaces in Ground and Excited Electronic States 5. Structures and Dipole Moments of Molecules in Their Electronically Excited States 6. Two-Color Pulsed-Field Ionization-Photoelectron Spectroscopy: A Quest to Benchmark State-of-the-Art ab initio Quantum Electronic Structure Calculations of Spectroscopic and Energetic Properties for Transition Metal-Containing Species 7. Advances in Far-Ultraviolet Spectroscopy in the Solid and Liquid States 8. Development of Sub-10 fs Visible-NIR, UV, and DUV Pulses and Their Applications to Ultrafast Spectroscopy 9. Biomedical Applications of Surface-Enhanced Raman Scattering Spectroscopy 10. SERS Biomedical Applications: Diagnostics, Forensics, and Metabolomics 11. Quantitative Spectrometry of Complex Molecular Systems by Hypothetical Addition Multivariate Analysis With Numerical Differentiation (HAMAND) 12. Progress in FAST CARS Toward Quantum Biophotonics 13. Coherent Raman Generation in Solid-State Materials Using Spatial and Temporal Laser Field Shaping 14. Vibrational Optical Activity: From Small Chiral Molecules to Protein Pharmaceuticals and Beyond 15. High-Resolution Laboratory Terahertz Spectroscopy and Applications to Astrophysics 16. Studying Interaction, Ion-Pair Formation, and Mixing Behavior of Protic Ionic Liquids by Means of Far-Infrared Spectroscopy 17. Advancements in Microwave Spectroscopy 18. Nitric Oxide Laser-Induced Fluorescence Imaging Methods and Their Application to Study High-Speed Flows 19. Photogeneration of Rare Molecules in Cryogenic Matrices: Spectroscopists' Adventures in Wonderland 20. Matrix Isolation Spectroscopic Studies: Thermal and Soft Photochemical Bimolecular Reactions 21. Theory of Enantiomer-Specific Microwave Spectroscopy.
  • (source: Nielsen Book Data)9780128112205 20171211
Frontiers and Advances in Molecular Spectroscopy once again brings together the most eminent scientists from around the world to describe their work at the cutting-edge of molecular spectroscopy. Much of what we know about atoms, molecules and the nature of matter has been obtained using spectroscopy over the last one hundred years or so. Going far beyond the topics discussed in Jaan Laane's earlier book on the subject, these chapters describe new methodologies and applications, instrumental developments and theory, which are taking spectroscopy into still new frontiers. The robust range of topics once again demonstrates the wide utility of spectroscopic techniques. New topics include ultrafast spectroscopy of the transition state, SERS/far-uv spectroscopy, femtosecond coherent anti-Stokes Raman spectroscopy, high-resolution laser induced fluorescence spectroscopy, Raman spectroscopy and biosensors, vibrational optical activity, ultrafast two-dimensional spectroscopy, biology with x-ray lasers, isomerization dynamics and hydrogen bonding, single molecule imaging, spectra of intermediates, matrix isolation spectroscopy and more.
(source: Nielsen Book Data)9780128112205 20171211
1 online resource.
  • 1. Linear and non-linear Teraherz spectroscopy and Applications to biological and pharmaceutical sciences 2. Recent developments in the mid-infrared spectroscopy3. Near-IR Spectroscopy and its applications4. Two-Dimensional Correlation Spectroscopy: Applications in Vibrational and Optical Spectroscopy5. Spectroscopy of Cold Molecules in matrices: Study of conformational changes, Non-covalent interactions, and Noble-gas compounds6. Ultrafast Coherent Spectroscopy/Microscopy and Applications7. SERS, Single-Molecule SERS, and TERS (Tip-enhanced Raman Spectroscopy)8. Femtosecond spectroscopy and investigation of ultrafast dynamics in condensed matters9. Laser spectroscopy for nano-materials10. Recent Advances in Resonance Raman Spectroscopy11. Laser Applications to spectroscopy of unstable species12. Laser Breakdown spectroscopy and Applications13. Photoacoustic Spectroscopy14. Application of Raman spectroscopy in Art and Cultural Heritage materials (Pigment Analysis, Biomolecules, Corrosion, Ceramics, Glasses, and Enamels, Minerals and Gemstones etc.).
  • (source: Nielsen Book Data)9780128498835 20171017
Molecular and Laser Spectroscopy: Advances and Applications provides students and researchers with an up-to-date understanding of the fast-developing area of molecular and laser spectroscopy. Editor V.P. Gupta has brought together the eminent scientists on a selection of topics to develop a systematic approach, first covering basic principles needed to understand each cutting-edge technique and application. This book acts as a standard reference for advanced students of molecular and laser spectroscopy and as a graduate text for new entrants in the field. The book covers a wide range of applications of molecular and laser spectroscopy in diverse areas ranging from materials to medicine and defence, biomedical research, environmental monitoring, forensic investigations, food and agriculture, and chemical, pharmaceutical and petrochemical processes. Researchers and scientific personnel in these fields will learn the latest techniques in order to put them to practical use in their work.
(source: Nielsen Book Data)9780128498835 20171017
1 online resource (368 pages).
  • Instrumental Platforms for NMR-based Metabolomics-- NMR Pulse Sequences for Metabolomics-- NMR Spectroscopy of Urine-- NMR Spectroscopy of Serum and Plasma-- High-resolution Magic-angle Spinning (HR-MAS) NMR Spectroscopy-- Investigation of Tumor Metabolism by High-resolution Magic-angle Spinning (HR-MAS) Magnetic Resonance Spectroscopy (MRS)-- NMR in Environmental and Nutritional Research-- NMR Foodomics-- NMR-based Metabolomics: Understanding Plant Chemistry and Identification of Biologically Active Compounds-- 1H NMR-based Metabolic Profiling in Infectious Disease Research-- Imaging Metabolic Processes in Living Systems with Hyperpolarised 13C Magnetic Resonance-- Advances in Computational Analysis of Metabolomic NMR Data-- NMR Spectroscopy of Cell Culture, Tissues, and Other Biofluids.
  • (source: Nielsen Book Data)9781782627937 20180226
In the rapidly growing field of metabolomics, a comprehensive book describing the state of the art in the application of NMR spectroscopy will be a key title for practitioners. Providing a unique resource of background knowledge, resources, instrumental platforms and software, this book will introduce relevant theory to the researcher as well as serve as a practical guide detailing key experiments and data handling procedures. Information available on common sample types will be described together with reference to the latest web-based resources available. Application-specific considerations will be discussed for a wide range of research topics. Written by an expert team as a service to the metabolomics community, this book will appeal to NMR spectroscopists, analytical chemists and biochemists especially those with an interest in medical applications.
(source: Nielsen Book Data)9781782627937 20180226
1 online resource.
Omics Technologies and Bio-Engineering: Towards Improving Quality of Life, Volume 1 is a unique reference that brings together multiple perspectives on omics research, providing in-depth analysis and insights from an international team of authors. The book delivers pivotal information that will inform and improve medical and biological research by helping readers gain more direct access to analytic data, an increased understanding on data evaluation, and a comprehensive picture on how to use omics data in molecular biology, biotechnology and human health care.
1 online resource
Thermal analysis comprises a group of techniques used to determine the physical or chemical properties of a substance as it is heated, cooled, or held at constant temperature. It is particularly important for polymer characterization, but also has major application in analysis of pharmaceuticals and foodstuffs. This comprehensive handbook presents practical and theoretical aspects of the key techniques of DSC, TGA, TMA, DMA, and related methods. It also includes separate chapters on the glass transition, polymers, polymorphism, purity determination, and method development. The large number of practical examples included should inspire readers toward new ideas for applications in their own fields of work. The chapters are independent of one another and can be read individually in any desired order. Based on years of experience in thermal analysis of users, application specialists, consultants, and course instructors, this book provides practical help to newcomers, inexperienced users, and anyone else interested in the practical aspects of thermal analysis. With the purchase of this book, you also receive a free personal access code to download the eBook.
(source: Nielsen Book Data)9781569906439 20180611
1 online resource (1 files) : digital, PDF file.
Each year since 2015, NREL has presented Annual Technology Baseline (ATB) in a spreadsheet that contains detailed cost and performance data (both current and projected) for renewable and conventional technologies. The spreadsheet includes a workbook for each technology. This spreadsheet provides data for the 2017 ATB. In this edition of the ATB, offshore wind power has been updated to include 15 technical resource groups. And, two options are now provided for representing market conditions for project financing, including current market conditions and long-term historical conditions. For more information, see https://atb.nrel.gov/.
1 online resource (Article No. 43401) : digital, PDF file.
Here we report the first example of a class of additively manufactured carbon fiber reinforced composite (AMCFRC) materials which have been achieved through the use of a latent thermal cured aromatic thermoset resin system, through an adaptation of direct ink writing (DIW) 3D-printing technology. We have developed a means of printing high performance thermoset carbon fiber composites, which allow the fiber component of a resin and carbon fiber fluid to be aligned in three dimensions via controlled micro-extrusion and subsequently cured into complex geometries. Characterization of our composite systems clearly show that we achieved a high order of fiber alignment within the composite microstructure, which in turn allows these materials to outperform equivalently filled randomly oriented carbon fiber and polymer composites. Moreover, our AM carbon fiber composite systems exhibit highly orthotropic mechanical and electrical responses as a direct result of the alignment of carbon fiber bundles in the microscale which we predict will ultimately lead to the design of truly tailorable carbon fiber/polymer hybrid materials having locally programmable complex electrical, thermal and mechanical response.
1 online resource (p. 3493-3504) : digital, PDF file.
Here, the Frenkel exciton model is a useful tool for theoretical studies of multichromophore systems. We recently showed that the exciton model could be used to coarse-grain electronic structure in multichromophoric systems, focusing on singly excited exciton states. However, our previous implementation excluded charge-transfer excited states, which can play an important role in light-harvesting systems and near-infrared optoelectronic materials. Recent studies have also emphasized the significance of charge-transfer in singlet fission, which mediates the coupling between the locally excited states and the multiexcitonic states. In this work, we report on an ab initio exciton model that incorporates charge-transfer excited states and demonstrate that the model provides correct charge-transfer excitation energies and asymptotic behavior. Comparison with TDDFT and EOM-CC2 calculations shows that our exciton model is robust with respect to system size, screening parameter, and different density functionals. Inclusion of charge-transfer excited states makes the exciton model more useful for studies of singly excited states and provides a starting point for future construction of a model that also includes double-exciton states.
1 online resource (p. 3554-3565) : digital, PDF file.
We have used ab initio molecular dynamics (AIMD) to characterize water properties using two meta-generalized gradient approximation (meta-GGA) functionals, M06-L-D3 and B97M-rV, and compared their performance against a standard GGA corrected for dispersion, revPBE-D3, at ambient conditions (298 K, and 1 g cm<sup>–3</sup> or 1 atm). Simulations of the equilibrium density, radial distribution functions, self-diffusivity, the infrared spectrum, liquid dipole moments, and characterizations of the hydrogen bond network show that all three functionals have overcome the problem of the early AIMD simulations that erroneously found ambient water to be highly structured, but they differ substantially among themselves in agreement with experiment on this range of water properties. We show directly using water cluster data up through the pentamer that revPBE-D3 benefits from a cancellation of its intrinsic functional error by running classical trajectories, whereas the meta-GGA functionals are demonstrably more accurate and would require the simulation of nuclear quantum effects to realize better agreement with all cluster and condensed phase properties.
Compositions and methods of making a modified polyhydroxylated polymer comprising a polyhydroxylated polymer having reversibly modified hydroxyl groups, whereby the hydroxyl groups are modified by an acid-catalyzed reaction between a polydroxylated polymer and a reagent such as acetals, aldehydes, vinyl ethers and ketones such that the modified polyhydroxylated polymers become insoluble in water but freely soluble in common organic solvents allowing for the facile preparation of acid-sensitive materials. Materials made from these polymers can be made to degrade in a pH-dependent manner. Both hydrophobic and hydrophilic cargoes were successfully loaded into particles made from the present polymers using single and double emulsion techniques, respectively. Due to its ease of preparation, processability, pH-sensitivity, and biocompatibility, of the present modified polyhydroxylated polymers should find use in numerous drug delivery applications.
The feasibility of manufacturing hexagonal boron nitride objects via additive manufacturing techniques was investigated. It was demonstrated that it is possible to hot-extrude thermoplastic filaments containing uniformly distributed boron nitride particles with a volume concentration as high as 60% and that these thermoplastic filaments can be used as feedstock for 3D-printing objects using a fused deposition system. Objects 3D-printed by fused deposition were subsequently sintered at high temperature to obtain dense ceramic products. In a parallel study the behavior of hexagonal boron nitride in aqueous solutions was investigated. It was shown that the addition of a cationic dispersant to an azeotrope enabled the formulation of slurries with a volume concentration of boron nitride as high as 33%. Although these slurries exhibited complex rheological behavior, the results from this study are encouraging and provide a pathway for manufacturing hexagonal boron nitride objects via robocasting.
1 online resource (Article No. 13945 ): digital, PDF file.
Here, IRMOF-74 analogues are among the most widely studied metal-organic frameworks (MOFs) for adsorption applications because of their one-dimensional channels and high metal density. Most studies involving the IRMOF-74 series assume that the crystal lattice is rigid. This assumption guides the interpretation of experimental data, as changes in the crystal symmetry have so far been ignored as a possibility in the literature. Here, we report a deformation pattern, induced by the adsorption of argon, for IRMOF-74-V. This work has two main implications. First, we use molecular simulations to demonstrate that the IRMOF-74 series undergoes a deformation that is similar to the mechanism behind breathing MOFs, but is unique because the deformation pattern extends beyond a single unit cell of the original structure. Second, we provide an alternative interpretation of experimental small-angle X-ray scattering profiles of these systems, which changes how we view the fundamentals of adsorption in this MOF series.
The present invention provides an adsorbent catalytic nanoparticle including a mesoporous silica nanoparticle having at least one adsorbent functional group bound thereto. The adsorbent catalytic nanoparticle also includes at least one catalytic material. In various embodiments, the present invention provides methods of using and making the adsorbent catalytic nanoparticles. In some examples, the adsorbent catalytic nanoparticles can be used to selectively remove fatty acids from feedstocks for biodiesel, and to hydrotreat the separated fatty acids.
A process includes casting a solution including poly(phenylene oxide), inorganic nanoparticles, a solvent, and a non-solvent on a substrate; and removing the solvent to form a porous film; wherein: the porous film is configured for use as a porous separator for a lithium ion battery.
1 online resource (115-124) : digital, PDF file.
Here we discuss the oxygen reduction reaction (ORR) is one of the major factors that is limiting the overall performance output of microbial fuel cells (MFC). In this study, Platinum Group Metal-free (PGM-free) ORR catalysts based on Fe, Co, Ni, Mn and the same precursor (Aminoantipyrine, AAPyr) were synthesized using identical sacrificial support method (SSM). The catalysts were investigated for their electrochemical performance, and then integrated into an air-breathing cathode to be tested in “clean” environment and in a working microbial fuel cell (MFC). Their performances were also compared to activated carbon (AC) based cathode under similar conditions. Results showed that the addition of Mn, Fe, Co and Ni to AAPyr increased the performances compared to AC. Fe-AAPyr showed the highest open circuit potential (OCP) that was 0.307 ± 0.001 V (vs. Ag/AgCl) and the highest electrocatalytic activity at pH 7.5. On the contrary, AC had an OCP of 0.203 ± 0.002 V (vs. Ag/AgCl) and had the lowest electrochemical activity. In MFC, Fe-AAPyr also had the highest output of 251 ± 2.3 μWcm<sup>–2</sup>, followed by Co-AAPyr with 196 ± 1.5 μWcm<sup>–2</sup>, Ni-AAPyr with 171 ± 3.6 μWcm<sup>–2</sup>, Mn-AAPyr with 160 ± 2.8 μWcm<sup>–2</sup> and AC 129 ± 4.2 μWcm<sup>–2</sup>. The best performing catalyst (Fe-AAPyr) was then tested in MFC with increasing solution conductivity from 12.4 mScm<sup>–1</sup> to 63.1 mScm<sup>–1</sup>. A maximum power density of 482 ± 5 μWcm<sup>–2</sup> was obtained with increasing solution conductivity, which is one of the highest values reported in the field.
1 online resource (Article No. 15541) : digital, PDF file.
Terrestrial vegetation emits vast quantities of volatile organic compounds (VOCs) to he atmosphere1-3, which influence oxidants and aerosols leading to complex feedbacks on air quality and climate4-6. Isoprene dominates global non-methane VOC emissions with tropical regions contributing ~80% of global isoprene emissions2. Isoprene emission rates vary over several orders of magnitude for different plant species, and characterizing this immense biological chemodiversity is a challenge for estimating isoprene emission from tropical forests. Here we present the isoprene emission estimates from aircraft direct eddy covariance measurements over the pristine Amazon forest. We report isoprene emission rates that are 3 times higher than satellite top-down estimates and 35% higher than model predictions based on satellite land cover and vegetation specific emission factors (EFs). The results reveal strong correlations between observed isoprene emission rates and terrain elevations which are confirmed by similar correlations between satellite-derived isoprene emissions and terrain elevations. We propose that the elevational gradient in the Amazonian forest isoprene emission capacity is determined by plant species distributions and can explain a substantial degree of isoprene emission variability in tropical forests. Finally, we apply this approach over the central Amazon and use a model to demonstrate the impacts on regional air quality.
1 online resource (20 p.) : digital, PDF file.
The goal of this project is to characterize and document the differences between 4 sets of microclad samples, and provide this information to the detonator Design Agency (Q-6) for the purposes of evaluating “similitude” for stockpile use.
1 online resource (4 p.) : digital, PDF file.
In order to appropriately model and predict the chemical integrity and performance of cementitious materials used for waste immobilization at the Savannah River Site (SRS), it is critical to understand the I-129 solubility and distribution within the tank farm. Iodine in radioactive waste and in environmental media is typically highly mobile and long lived. Iodine is ubiquitous in SRS tank waste and waste forms. The iodine is assumed to be soluble and present at low levels in Performance Assessments (PAs) for SRS Tank Farms, and is one of the dose drivers in the PAs for both the SRS Salt Disposal Facility (SDF) and the H-Area Tank Farm (HTF). Analysis of tank waste samples is critical to understanding the Tank Farm iodine inventory and reducing disposal uncertainty. Higher than expected iodine levels have recently been observed in residual solids isolated from some SRS tanks prior to closure, indicating uncertainty regarding the chemical species involved. If the iodine inventory uncertainty is larger than anticipated, future work may be necessary to reduce the uncertainty. This memorandum satisfies a portion of the work scope identified in Task Plan SRNL-RP-2016-00651. A separate memorandum issued previously, reported historical unpublished I-129 data, a significant portion of which was below detectable analytical limits. This memorandum includes iodine and general chemical analysis results for six archived SRNL samples which were previously reported to have I-129 concentrations below detectable limits. Lower sample dilution factors were used for the current analyses in order to obtain concentrations above detection. The samples analyzed included surface and depth samples from SRS tanks 30, 32, and 39.


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