79 research outputs found
Nuclear quadrupole coupling interaction at molybdenum (V) centers
Imperfect: lacks leaves 28, 45, 46.Thesis (B.S.) in Chemistry--University of Illinois at Urbana-Champaign, 1985.Bibliography: leaves 53-54.Microfiche of typescript. [Urbana, Ill.] : Photographic Services, University of Illinois, U of I Library, [1988]. 2 microfiches (59 frames) : negative ; 11 x 15 cm
Non-classical kinetics in hydrogen isotope exchange reaction on supported platinum catalysts: Experiments and simulations.
Non-classical kinetic behavior of the hydrogen isotope exchange reaction on supported platinum catalysts has been investigated by experimental and computer simulation studies. Monte Carlo simulations of the reaction A2 + B2 Products have provided several interesting models for experimental study. Anomalous reaction kinetics and reaction orders are exhibited at early time on a one-dimensional "large lattice" system. Non-classical reaction orders have also been found at steady state on "low dimensionality", one- and two-dimensional many-island systems. The former is attributed to strong initial reactant correlation which dissipates in time due to surface diffusion whereas the latter is attributed to a combination of effective "low dimensionality" and low concentration. A new analytical approach, which monitors neighbor pair densities instead of conventional surface concentration, has produced a clearer understanding of the non-classical results above by providing the nearest neighbor pair distance distributions, the pair orders, and the "local" vs. global concentrations. A computer algorithm scheme, which successfully monitors pair distributions, has also been developed for this simulation study. Four different platinum catalysts, with average metal island sizes ranging from 10 to 45 A, have been studied. The metal catalyst island sizes have been characterized by transmission electron microscopy. In situ analysis of both reactant and product gas concentrations have been provided by time-of-flight mass spectrometry. A theoretical methodology which correlates the surface reaction rate with the bulk gas pressure change rate for each reactant and product has been developed. Three catalysts with smaller metal islands have exhibited an early time tail in their product gas pressure curves which could not be fitted by the equation above whereas one catalyst, with an average of 45 A metal island, produced a bulk product gas pressure curve which could be fitted nicely due to the absence of the tail. The results indicate the possibility that the non-classical surface reaction rate, signified by the early time tail in the bulk gas pressure curve, may be attributed to low dimensionality of the system. It is interesting that both computer simulation and experimental study results show "dimensionality effects" on non-classical kinetics.Ph.D.ChemistryUniversity of Michigan, Horace H. Rackham School of Graduate Studieshttp://deepblue.lib.umich.edu/bitstream/2027.42/104445/1/9527599.pdfDescription of 9527599.pdf : Restricted to UM users only
Connections and Overlap Between Capacity Building Measures, Nonprofit Management Competencies, and Training Needs of Nonprofit Managers
PURPOSE: Studies conducted in the past twenty years have discussed capacity building needs of nonprofit organizations, nonprofit management competencies, and the training needs of nonprofit managers. However, many of these studies have been discussed in silos, separate journal articles and studied in different areas of the nonprofit management literature. There has been a scarcity of studies that document and track the common terms discussed across the nonprofit management literature. SUBJECTS: Common terms discussed across the nonprofit management literature. METHODS AND MATERIALS: Clustered social network analysis, and more specifically the open source software tool, Gephi, was used to identify the overlap in nonprofit capacity building measures, nonprofit management competencies and training needs terms listed in the literature. ANALYSES: The authors used social network analysis and identified12 terms were the most commonly discussed across the literature. Then these 12 terms were compared to the nonprofit management education literature and the courses being offered in nonprofit graduate education. RESULTS: The findings revealed 12 terms were hubs, meaning 12 terms were the most connected across literature. These terms included: Leadership, Planning, Public Relations, Volunteer Management, Financial Management, Communications, Marketing, Governance, Data Utilization, Human Resources, Fundraising, Information Technology. Leadership was listed the most frequently across all studies. CONCLUSIONS: Findings revealed that nonprofit management education are missing some of the important competencies, skills and training needs of nonprofit managers as identified in the social network analysis
MALDI-TOF spectrum of tryptic digests of mDHFR_38Am.
<p>Peptide Z38 (residues 26–39; NGDLPWPPLRNEZK; Z indicates 2Nal) contains an amber codon at the 38<sup>th</sup> position. Peptide K38 (residues 26–39; NGDLPWPPLRNEKK; K indicates Lys) contains Lys at the 38<sup>th</sup> position. Another tryptic digest (residues 85–98; ELKEPPRGAHFLAK) contains Phe.</p
Occupancy of UUU and UAG codons by various amino acids.
<p>Occupancy of UUU and UAG codons by various amino acids.</p
Fluorescence intensities of cells expressing GFP3.
<p>GFP3 was expressed in MPC390 expression hosts outfitted with yPheRS_naph and ytRNA<sup>Phe</sup><sub>CAA</sub> in minimal medium supplemented with 17 amino acids, 1.25 μM Leu, 5.0 μM Phe, 50 μM Trp, and no 2Nal (A); 3 mM 2Nal (B).</p
Flexible Crystalline-Silicon Photovoltaics: Light Management with Surface Structures
Flexible solar cells have been intensively studied in recent years for their applicability on curved or uneven surfaces, which augments their versatility toward various applications. Although emerging materials such as organics/polymers, perovskite, amorphous silicon, and copper indium gallium selenide have been used as light absorption materials for flexible solar cells, the commercialization of these materials is limited owing to their efficiency degradation, usage of toxic materials, short lifespan, or scarcity. On the contrary, crystalline silicon (c-Si) solar cells have been commercialized because of their low manufacturing cost, long lifespan of over 20 years, and high power-conversion efficiency (PCE) of ???26.7%. However, the development of flexible solar cells using c-Si substrate poses an intrinsic problem resulting from its rigid material characteristics. In recent years, flexible solar cells using thin c-Si wafers have become more attractive with archiving a higher PCE than that of the emerging flexible solar cells. In addition, the mechanical flexibility can be realized using a thin c-Si film with a thickness of ???50 ??m, which is a quarter of the substrate thickness of conventional c-Si solar cells. Nonetheless, thin c-Si-based flexible solar cells face critical challenges because of severe light absorption loss in the entire wavelength region (300???1100 nm) because of the low absorption coefficient and surface reflection of c-Si. The development of the c-Si flexible solar cells should focus on improving the light absorption of thin c-Si films as well as maintaining the mechanical flexibility and stability of the thin c-Si solar cells. Thus, in this Account, we introduce high-aspect-ratio c-Si microwires and a random inverted-pyramidal-transparent optical film as promising surface structures for the efficient trapping of incident light in thin c-Si films. Moreover, the principles regarding the improvement in light absorption of these surface structures are discussed along with the implementable strategies for maximizing PCE of the c-Si flexible solar cells. Lastly, perspectives on further improvement of the PCE and stability of the flexible c-Si solar cells are presented
Forced Ambiguity of the Leucine Codons for Multiple-Site-Specific Incorporation of a Noncanonical Amino Acid - Fig 2
<p><b>Extended wobble rules (A).</b> Mutant ytRNA<sup>Phe</sup><sub>AAA</sub> recognizing UUU and UUC Phe codons by Watson-Crick (W/C) base pairing and wobble base pairing, respectively (B). Mutant ytRNA<sup>Phe</sup><sub>CAA</sub> recognizing UUG Leu codon by W/C base pairing but none of other Leu codons (C).</p
Scheme of 2Nal incorporation into multiple UUG Leu codons based on forced ambiguity of the Leu codons.
<p><i>E</i>. <i>coli</i> leucyl-tRNA synthetase (LeuRS) charges Leu into its cognate tRNA<sup>Leu</sup><sub>s</sub> containing UAA anticodon (<i>E</i>. <i>coli</i> tRNA<sup>Leu</sup><sub>UAA</sub>) and CAA anticodon (<i>E</i>. <i>coli</i> tRNA<sup>Leu</sup><sub>CAA</sub>). Leu charged into <i>E</i>. <i>coli</i> tRNA<sup>Leu</sup><sub>UAA</sub> is incorporated into multiple UUA Leu codon sites of a target protein. The yPheRS_naph charges 2Nal into ytRNA<sup>Phe</sup> containing CAA anticodon (ytRNA<sup>Phe</sup><sub>CAA</sub>). Then, 2Nal is incorporated into multiple UUG Leu codons. According to the (extended) wobble rules, ytRNA<sup>Phe</sup><sub>CAA</sub> and <i>E</i>. <i>coli</i> tRNA<sup>Leu</sup><sub>UAA</sub> do not recognize UUA and UUG, respectively. UUG Leu codons can also be recognized by Leu-charged <i>E</i>. <i>coli</i> tRNA<sup>Leu</sup><sub>CAA</sub> resulting in partial occupancy of UUG codons by Leu.</p
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