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Book
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.
Book
1 online resource (p. 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.
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
1 online resource.
EBSCOhost Access limited to 1 user
A method of stripping tritium from flowing stream of molten salt includes providing a tritium-separating membrane structure having a porous support, a nanoporous structural metal-ion diffusion barrier layer, and a gas-tight, nonporous palladium-bearing separative layer, directing the flowing stream of molten salt into contact with the palladium-bearing layer so that tritium contained within the molten salt is transported through the tritium-separating membrane structure, and contacting a sweep gas with the porous support for collecting the tritium.
Book
1 online resource
  • Front Cover; Applications in High Resolution Mass Spectrometry; Applications in HighResolution Mass Spectrometry: Food Safety and Pesticide Residue Analysis; Copyright; Contents; List of Contributors; Preface; 1
  • HRMS: Fundamentals and Basic Concepts; 1.1 INTRODUCTION (TO HIGH-RESOLUTION MASS SPECTROMETRY); 1.1.1 BASIC CONCEPTS (UNITS AND DEFINITIONS); 1.1.2 LOW-RESOLUTION MASS SPECTROMETRY VERSUS HIGH-RESOLUTION MASS SPECTROMETRY; 1.2 RESOLUTION AND MASS RESOLVING POWER; 1.3 ACCURATE MASS MEASUREMENT: EXACT MASS AND MASS DEFECT; 1.4 MASS CALIBRATION IN HIGH-RESOLUTION MASS SPECTROMETRY
  • 1.5 GENERAL CONSIDERATIONSAcknowledgments; REFERENCES; 2
  • HRMS: Hardware and Software; 2.1 INTRODUCTION; 2.2 PRINCIPLES OF HIGH-RESOLUTION MASS SPECTROMETRY ANALYZERS; 2.2.1 TIME-OF-FLIGHT; 2.2.2 FOURIER TRANSFORM ION CYCLOTRON RESONANCE; 2.2.3 ORBITRAP; 2.3 TIME-OF-FLIGHT MASS SPECTROMETRY: INSTRUMENT CONFIGURATION AND MAIN FEATURES; 2.3.1 STAND-ALONE ELECTROSPRAY IONIZATION TIME-OF-FLIGHT AND HYBRID QUADRUPOLE TIME-OF-FLIGHT INSTRUMENTATION; 2.3.2 IMPROVEMENTS OF CURRENT (QUADRUPOLE) TIME-OF-FLIGHT INSTRUMENTATION; 2.3.3 ION MOBILITY QUADRUPOLE TIME-OF-FLIGHT
  • 2.3.4 HYBRID ION TRAP TIME-OF-FLIGHT2.3.5 GAS CHROMATOGRAPHY-TIME-OF-FLIGHT AND GAS CHROMATOGRAPHY-QUADRUPOLE TIME-OF-FLIGHT; 2.4 ORBITRAP ANALYZERS: INSTRUMENT CONFIGURATIONS AND MAIN FEATURES; 2.5 ACQUISITION MODES IN HIGH-RESOLUTION MASS SPECTROMETRY; 2.5.1 DATA-DEPENDENT ACQUISITION; 2.5.2 DATA-INDEPENDENT ACQUISITION; 2.5.3 POSTACQUISITION APPROACHES; 2.6 DATABASES AND THE INTERNET RESOURCES FOR HIGH-RESOLUTION MASS SPECTROMETRY; Acknowledgments; REFERENCES; 3
  • Analytical Strategies Used in HRMS; 3.1 INTRODUCTION; 3.2 ADVANTAGES OF HIGH-RESOLUTION MASS SPECTROMETRY IN PESTICIDE ANALYSIS
  • 3.2.1 SELECTIVITY IN HIGH-RESOLUTION MASS SPECTROMETRY: ACCURATE MASS AND RESOLUTION IN QUALITATIVE ANALYSIS3.2.2 IMPROVING SELECTIVITY BY TANDEM MASS SPECTROMETRY INFORMATION; 3.2.3 QUANTITATIVE PERFORMANCE; 3.3 DATA ANALYSIS WORKFLOWS IN HIGH-RESOLUTION MASS SPECTROMETRY; 3.3.1 QUALITATIVE SCREENING METHOD VALIDATION; 3.3.2 NONTARGET ANALYSIS; 3.4 CONCLUSIONS; Acknowledgments; REFERENCES; FURTHER READING; 4
  • Current Legislation on Pesticides; 4.1 INTRODUCTION; 4.2 PESTICIDES; 4.2.1 IDENTITY AND PHYSICOCHEMICAL PROPERTIES; 4.2.2 PESTICIDES CLASSIFICATION
  • 4.2.3 PESTICIDE METABOLITES AND TRANSFORMATION PRODUCTS4.3 LEGISLATION; 4.3.1 PESTICIDES AUTHORIZATION; 4.3.2 MAXIMUM RESIDUE LIMITS; 4.3.3 MONITORING PROGRAMS; 4.4 ANALYTICAL QUALITY CONTROL-METHOD VALIDATION; 4.4.1 GUIDELINES FOR PESTICIDE RESIDUE ANALYSIS; 4.4.1.1 Method Validation for Pesticide Residues; 4.4.1.2 Quality Assurance; 4.4.1.3 Uncertainty; 4.5 MASS SPECTROMETRY IN PESTICIDE RESIDUE ANALYSIS; 4.5.1 MASS SPECTROMETRY IDENTIFICATION AND CONFIRMATION; 4.5.2 POTENTIAL OF HIGH-RESOLUTION MASS SPECTROMETRY IN PESTICIDE RESIDUE ANALYSIS; REFERENCES
  • 5
  • Advanced Sample Preparation Techniques for Pesticide Residues Determination by HRMS Analysis
The present invention relates to methods and compositions for increasing production of methyl ketones in a genetically modified host cell that overproduces .beta.-ketoacyl-CoAs through a re-engineered .beta.-oxidation pathway and overexpresses FadM.
Book
1 online resource (p. 762-771 ): digital, PDF file.
Femtosecond two-dimensional Fourier transform spectroscopy is used to determine the static bandgap inhomogeneity of a colloidal quantum dot ensemble. The excited states of quantum dots absorb light, so their absorptive two-dimensional (2D) spectra will typically have positive and negative peaks. It is shown that the absorption bandgap inhomogeneity is robustly determined by the slope of the nodal line separating positive and negative peaks in the 2D spectrum around the bandgap transition; this nodal line slope is independent of excited state parameters not known from the absorption and emission spectra. The absorption bandgap inhomogeneity is compared to a size and shape distribution determined by electron microscopy. The electron microscopy images are analyzed using new 2D histograms that correlate major and minor image projections to reveal elongated nanocrystals, a conclusion supported by grazing incidence small-angle X-ray scattering and high-resolution transmission electron microscopy. Finally, the absorption bandgap inhomogeneity quantitatively agrees with the bandgap variations calculated from the size and shape distribution, placing upper bounds on any surface contributions.
Book
1 online resource (p. 762-771 ): digital, PDF file.
Femtosecond two-dimensional Fourier transform spectroscopy is used to determine the static bandgap inhomogeneity of a colloidal PbSe quantum dot ensemble. It is shown that the absorption bandgap inhomogeneity is robustly determined by the slope of the nodal line separating positive and negative peaks in the 2D spectrum around the bandgap transition; this nodal line slope is independent of excited state parameters not known from the absorption and emission spectra. The absorption bandgap inhomogeneity is compared to a size and shape distribution determined by electron microscopy. The electron microscopy images are analyzed using new 2D histograms that correlate major and minor image projections to reveal elongated nanocrystals, a conclusion supported by grazing incidence small angle X-ray scattering and high resolution transmission electron microscopy. Lastly, the absorption bandgap inhomogeneity quantitatively agrees with the bandgap variations calculated from the size and shape distribution, placing upper bounds on any surface contributions.
A catalytic composition from earth-abundant transition metal salts and biomass is disclosed. A calcined catalytic composition formed from soybean powder and ammonium molybdate is specifically exemplified herein. Methods for making the catalytic composition are disclosed as are electrodes for hydrogen evolution reactions comprising the catalytic composition.
Book
1 online resource (19 p.) : digital, PDF file.
No abstract provided.
A composite oxygen transport membrane having a dense layer, a porous support layer and an intermediate porous layer located between the dense layer and the porous support layer. Both the dense layer and the intermediate porous layer are formed from an ionic conductive material to conduct oxygen ions and an electrically conductive material to conduct electrons. The porous support layer has a high permeability, high porosity, and a microstructure exhibiting substantially uniform pore size distribution as a result of using PMMA pore forming materials or a bi-modal particle size distribution of the porous support layer materials. Catalyst particles selected to promote oxidation of a combustible substance are located in the intermediate porous layer and in the porous support adjacent to the intermediate porous layer. The catalyst particles can be formed by wicking a solution of catalyst precursors through the porous support toward the intermediate porous layer.
Catalysts that include at least one catalytically active element and one helper catalyst can be used to increase the rate or lower the overpotential of chemical reactions. The helper catalyst can simultaneously act as a director molecule, suppressing undesired reactions and thus increasing selectivity toward the desired reaction. These catalysts can be useful for a variety of chemical reactions including, in particular, the electrochemical conversion of CO.sub.2 or formic acid. The catalysts can also suppress H.sub.2 evolution, permitting electrochemical cell operation at potentials below RHE. Chemical processes and devices using the catalysts are also disclosed, including processes to produce CO, OH.sup.-, HCO.sup.-, H.sub.2CO, (HCO.sub.2).sup.-, H.sub.2CO.sub.2, CH.sub.3OH, CH.sub.4, C.sub.2H.sub.4, CH.sub.3CH.sub.2OH, CH.sub.3COO.sup.-, CH.sub.3COOH, C.sub.2H.sub.6, O.sub.2, H.sub.2, (COOH).sub.2, or (COO.sup.-).sub.2, and a specific device, namely, a CO.sub.2 sensor.
The present invention, among other things, provides highly syndiotactic poly(dicyclopentadiene) and/or hydrogenated poly(dicyclopentadiene), compositions thereof, and compounds and methods for preparing the same. In some embodiments, a provided compound is a compound of formula I, II or III. In some embodiments, a provided method comprises providing a compound of formula I, II or III.
The present invention provides a catalyst including a mesoporous silica nanoparticle and a catalytic material comprising iron. In various embodiments, the present invention provides methods of using and making the catalyst. In some examples, the catalyst can be used to hydrotreat fatty acids or to selectively remove fatty acids from feedstocks.
Complexes of cobalt and nickel with tridentate ligand PNHP.sup.R are effective for hydrogenation of unsaturated compounds. Cobalt complex [(PNHP.sup.Cy)Co(CH.sub.2SiMe.sub.3)]BAr.sup.F.sub.4 (PNHP.sup.Cy=bis[2-(dicyclohexylphosphino)ethyl]amine, BAr.sup.F.sub.4=B(3,5-(CF.sub.3).sub.2C.sub.6H.sub.3).sub.4)) was prepared and used with hydrogen for hydrogenation of alkenes, aldehydes, ketones, and imines under mild conditions (25-60.degree. C., 1-4 atm H.sub.2). Nickel complex [(PNHP.sup.Cy)Ni(H)]BPh.sub.4 was used for hydrogenation of styrene and 1-octene under mild conditions. (PNP.sup.Cy)Ni(H) was used for hydrogenating alkenes.
Book
1 online resource
Book
1 online resource (Article No. 41121 ): digital, PDF file.
N-Acylethanolamines (NAEs) are a group of fatty acid amides that play signaling roles in diverse physiological processes in eukaryotes. We used fatty acid amide hydrolase (FAAH) degrades NAE into ethanolamine and free fatty acid to terminate its signaling function. In animals, chemical inhibitors of FAAH for therapeutic treatment of pain and as tools to probe deeper into biochemical properties of FAAH. In a chemical genetic screen for small molecules that dampened the inhibitory effect of N-lauroylethanolamine (NAE 12:0) on Arabidopsis thaliana seedling growth, we identified 6-(2-methoxyphenyl)-1,3-dimethyl-5-phenyl-1H-pyrrolo[3,4-d]pyrim idine-2,4(3 H, 6 H)-dione (or MDPD). MDPD alleviated the growth inhibitory effects of NAE 12:0, in part by enhancing the enzymatic activity of Arabidopsis FAAH (AtFAAH). In vitro, biochemical assays showed that MDPD enhanced the apparent Vmax of AtFAAH but did not alter the affinity of AtFAAH for its NAE substrates. Furthermore, structural analogs of MDPD did not affect AtFAAH activity or dampen the inhibitory effect of NAE 12:0 on seedling growth indicating that MDPD is a specific synthetic chemical activator of AtFAAH. Our study demonstrates the feasibility of using an unbiased chemical genetic approach to identify new pharmacological tools for manipulating FAAH- and NAE-mediated physiological processes in plants.

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