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  • 1
    Electronic Resource
    Electronic Resource
    Alkoxy sol-gel derived Y3−xAl5O12:Tbx thin films as efficient cathodoluminescent phosphors (2001)
    Woodbury, NY : American Institute of Physics (AIP)
    Applied Physics Letters 78 (2001), S. 3800-3802 
    Details
    ISSN: 1077-3118
    Source: AIP Digital Archive
    Topics: Physics
    Notes: Thin-film Y3−xAl5O12:Tbx3+ (YAG:Tb) phosphor derived from a sol-gel chemistry is analyzed by x-ray diffraction, scanning electron microscopy, photoluminescence (PL) and cathodoluminescence (CL). The metal alkoxides organic precursors were chosen as the starting materials to form the sol-gel. This liquid sol-gel was spin coated on sapphire and silicon substrates to form the uniform thin films, then crystallized by annealing. The PL intensity of the crystallized film at 545 nm green emission was 15 times higher than that of the as-coated noncrystalline film. CL measurements show that luminance and efficiency are comparable to the films deposited by other techniques. © 2001 American Institute of Physics.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1063/1.1378313
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  • 2
    Electronic Resource
    Electronic Resource
    Enhanced-response pyroelectric heterostructures (2000)
    Woodbury, NY : American Institute of Physics (AIP)
    Applied Physics Letters 77 (2000), S. 2388-2390 
    Details
    ISSN: 1077-3118
    Source: AIP Digital Archive
    Topics: Physics
    Notes: We have observed enhanced pyroelectric responses in sub-100 nm, epitaxial Pb–Zr–Ti–O films contacted with conducting perovskite oxide top and bottom electrodes. These enhancements are obtained in capacitors where the bottom electrode is processed under reducing conditions. This leads to an asymmetric, temperature-dependent internal electric field that is produced within the ferroelectric capacitor and manifests itself as a strongly shifted ferroelectric hysteresis loop. Because the shifted coercive voltage lies near the unbiased operating point, the pyroelectric film has a large value of dP/dE. The product (dP/dE)/(dE/dT) gives rise to an enhanced pyroelectric response. Our data show that a 10–30 times increase in the pyroelectric response can be obtained over symmetric devices, with a concomitant improvement of the sensing figure-of-merit by three times. © 2000 American Institute of Physics.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1063/1.1316774
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  • 3
    Electronic Resource
    Electronic Resource
    DNAPL Flow Behavior in a Contaminated Aquifer: Evaluation of Field Data (1995)
    Oxford, UK : Blackwell Publishing Ltd
    Ground water monitoring & remediation 15 (1995), S. 0 
    Details
    ISSN: 1745-6592
    Source: Blackwell Publishing Journal Backfiles 1879-2005
    Topics: Energy, Environment Protection, Nuclear Power Engineering , Geosciences
    Notes: A pool of dense nonaqueous phase liquid (DNAPI.) containing TCE and other chlorinated solvents has been removed from the subsurface at Hill Air Force Base, Uthah. as part of an interim remedial action. The removal of the DNAPI. pool means that future off-site migration of dissolved contaminants in the ground water is minimized, and costs for final remedial actions are reduced. A pump-and-treat system recovered more than 23.000) gallons of DNAPI. and one million gallons of contaminated ground water from the aquifer. The efficiency of this remedial action was evaluated on the basis of extensive field and laboratory data. The behavior of DNAPI. flow in the aquifer sands was characterized by collecting core samples from two borings in the DNAPL pool and measuring relative permeabilities and DMAPI. saturation. Core Hooding results show that approximately one-third of the DNAPI. originally in the pool is not recovered by water displacement, but remains as a residual saturation held in place by capillary pressure. However, subsequent Hooding with two pore volumes of surfactant solution reduced the residual DNAPI. saturation in the sand by one order of magnitude. Analytical and numerical models for the DNAPI flow behavior at the site were developed. This is the first time that such models have been developed and applied to an actual DNAPI. pumping lest conducted in the field. Because measured permeabilities and residual saturations were used lo calibrate the models. the model predictions could be used lo provide valuable insights into the controlling mechanisms for DNAPL recovery. The data collection and modeling procedures outlined in this paper can be used lo enhance the efficiency and minimize the cost 10 clean up this and other DNAPI.-contaminated sites.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1111/j.1745-6592.1995.tb00560.x
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  • 4
    Electronic Resource
    Electronic Resource
    (Acetonitrile-N)(η4-2-methylbuta-1,3-diene)(η5-pentamethylcyclopentadienyl)ruthenium(II) trifluoromethanesulfonate (1999)
    Oxford [u.a.] : International Union of Crystallography (IUCr)
    Acta crystallographica 55 (1999), S. 2053-2055 
    Details
    ISSN: 1600-5759
    Source: Crystallography Journals Online : IUCR Backfile Archive 1948-2001
    Topics: Chemistry and Pharmacology , Geosciences , Physics
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1107/S0108270199012342
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  • 5
    Electronic Resource
    Electronic Resource
    Synthesis and characterization of phosphane-substituted hydroxyruthenocenes: crystal structure of [Ru(η^5-C"5H"4PPh"3)(η^5-C"5H"4OH)]PF"6
    Amsterdam : Elsevier
    Inorganica Chimica Acta 217 (1994), S. 203-207 
    Details
    ISSN: 0020-1693
    Keywords: Crystal structures ; Ruthenium complexes ; Substituted ruthenocene complexes
    Source: Elsevier Journal Backfiles on ScienceDirect 1907 - 2002
    Topics: Chemistry and Pharmacology
    Type of Medium: Electronic Resource
    URL: http://linkinghub.elsevier.com/retrieve/pii/0020-1693(93)03757-2
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  • 6
    Electronic Resource
    Electronic Resource
    Redox kinetics of metal complexes in nonaqueous solutions: Oxidation of a series of tris(1,10-phenanthroline)iron(II) ions by hexakis(trimethylphosphate)iron(III) in acetonitrile — A reactivity-selectivity relationship (1993)
    Springer
    Monatshefte für Chemie 124 (1993), S. 493-509 
    Details
    ISSN: 1434-4475
    Keywords: Nonaqueous electron transfer ; Iron(III)trimethylphosphate complexes ; Ligand exchange
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Zusammenfassung Es wurde die Kinetik der Outer-sphere Oxidation einer Reihe von Fe(Xphen) 3 2+ Ionen (X=H oder verschiedene Methylsubstituenten) mit Eisen(III), eingeführt als Fe(tmp)6(ClO4)3 (tmp=Trimethylphosphat), bei 25°C in Acetonitril (MeCN) untersucht. Diese Reaktionen sind sehr komplex, da gebundenestmp teilweise durchMeCN ausgetauscht wird, wobei der Ersatz einestmp-Moleküls durchMeCN das Redoxpotential um 0.2 V verschiebt. Deshalb sind die verschiedenen Solvatkomplexe in ihrer Reaktivität sehr unterschiedlich. Ein zweites wesentliches Merkmal der untersuchten Reaktionen ist der hohe Ladungstyp von +2/+3. Das bringt eine starke Erhöhung der Reaktionsgeschwindigkeit durch Elektrolytzusatz infolge von Ionenassoziation mit sich, die die Coulombsche Arbeit für die Bildung des Precursorkomplexes reduziert. Die Aufgabe bestand demnach in der Aufklärung von zwei Speziationsarten, der Solvations- und Ionenassoziationsgleichgewichte. Die Analyse weist auf das gleichzeitige Vorliegen von fünf Fe(tmp) n 3+ Species (n=2–6) hin, wobei vier von ihnen (n=2–5) reagieren. Zusätzlich gibt es für jedesn noch Ionenpaare und Ionentriplets mit Perchlorat. Eine zusätzliche Komplizierung ergibt sich, weil bestimmte Solvationsgleichgewichte nicht immer schnell sind im Vergleich zu den Redoxreaktionen, die dann nicht mehr pseudo-erster-Ordnung sind. Wenn auch die Geschwindigkeitskonstanten nicht mit der üblicherweise gewünschten Präzision angegeben werden können, sind zumindest zwei Ergebnisse nennenswert: (a) Es wird die relative Bedeutung der driving force und der Reaktantenladung für die Gesamtreaktivität hervorgehoben und (b) Je stärker die Reduktionskraft des Fe(Xphen) 3 2+ Ions, desto weniger kann es die verschiedenen Solvatspezies unterscheiden (Reaktivitäts-Selektivitäts-Beziehung).
    Notes: Summary The kinetics of outer-sphere oxidation of Fe(Xphen) 3 2+ ions (X=H or several methyl substituents) in acetonitrile (MeCN) solution by iron(III), introduced as Fe(tmp)6(ClO4)3 (tmp=trimethylphosphate), have been investigated at 25°C. The reactions are very complex because of solvation equilibria betweentmp andMeCN coordinated at Fe3+, with a reduction potential difference of 0.20 V for the replacement of onetmp byMeCN. This makes the various solvate species highly different in driving force. The second essential feature is the high charge-type of +2/+3. This brings about strong acceleration by salt because of ion association reducing the work necessary to overcome the Coulombic repulsion in forming the precursor complex. The task was to deconvolute two kinds of speciation: the ionic and the solvate speciations. The analysis suggests the concurrent existence of five Fe(tmp) n 3+ (n=2–6) species among which four species (n=2–5) are reacting, with an additional mono and bis perchlorate ion pair for eachn. Extra complications arise as some of the solvation equilibria are not always fast compared to the redox reactions, leading to non-first order rate constants. Although the rate constants could not be defined with the desired precision, at least two results are worth noting: (i) The relative effects of driving force and charge are highlighted in controlling overall reactivity. (ii) The stronger the reducing power of the Fe(Xphen) 3 2+ moiety, the less it can distinguish between the various solvate species (reactivity-selectivity relationship).
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00819517
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  • 7
    Electronic Resource
    Electronic Resource
    The substitution chemistry of RuCp* (temeda)Cl (1997)
    Springer
    Monatshefte für Chemie 128 (1997), S. 1189-1199 
    Details
    ISSN: 1434-4475
    Keywords: Ruthenium half-sandwich complexes ; Tetramethylethylenediamine ; Ruthenacycles
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Zusammenfassung Chloridabspaltung von RuCp*(tmeda)Cl (1,tmeda=Me2NCH2CH2NMe2) mittels NaBPh4 in CH2Cl2 führt zur Bildung des Halbsandwich-Komplexes RuCp*(η6-C6H5BPh3) (2), während in Gegenwart von CH3CN oder CO die beiden kationischen Verbindungen [RuCp*(tmeda)(CH3CN)]+ (3) und [RuCp*(tmeda)(CO)]+ (5) entstehen. In CH3CN als Lösungsmittel wird sogartmeda unter Bildung von [RuCp*(CH3CN)3]+ (4) verdrängt. Komplex1 reagiert sehr leicht mit terminalen Alkinen HC≡CR, wobei die Produkte stark von der Natur des SubstituentenR (Ph, SiMe3,n-Bu, COOEt) abhängen. Im Fall vonR=Ph entsteht der Ruthenacyclopentatrien-Komplex RuCp*(σσ′-C4Ph2H2)Cl (6), mitR=SiMe3 der Cyclobutadien-Komplex Ru(Cp*)(η4-C4H2(1,2-SiMe3)2)Cl (7), und im Fall vonR=n-Bu und COOEt bilden sich die binuklearen Komplexe (Cp*)RuCl2(η2:η4-μ2-C4H2(1,3-R)2)Ru(Cp*) (8,9). Überdies reagiert1 mit Maleinsäurediethylester in Gegenwart von LiCl zum neuen anionischen Komplex Li[Ru(Cp*) (η2-C2H2(COOEt)2)Cl2] (10). Von2,3,4,7 und10 wurden die Kristallstrukturen bestimmt.
    Notes: Summary Halide abstraction from RuCp*(tmeda)Cl (1,tmeda=Me2NCH2CH2NMe2) with NaBPh4 in CH2Cl2 leads to the formation of the sandwich complex RuCp*(η6-C6H5BPh3) (2). In the presence of CH3CN (1 equiv.) and CO, however, the cationic complexes [RuCp*(tmeda)(CH3CN)]+ (3) and [RuCp*(temeda)(CO)]+ (5) are obtained. In CH3CN,tmeda is also replaced giving [RuCp*(CH3CN)3]+ (4). Complex1 reacts readily with terminal acetylenes HC≡CR, the products depending on the nature ofR (Ph, SiMe3,n-Bu, COOEt). Thus, withR=Ph the ruthenacyclopentatriene complex RuCp*(σ,σ′-C4Ph2H2)Cl (6), withR=SiMe3 the cyclobutadiene complex Ru(Cp*)(σ4-C4H2(1,2-SiMe3)2)Cl (7), and withR=n-Bu and COOEt the binuclear complexes (Cp*)RuCl2(η2:η4-μ2-C4H2(1,3-R)2)Ru(Cp*) (8,9) are obtained. Furthermore, with diethyl maleate in the presence of 1 equiv. of LiCl,1 transforms into the new anionic complex Li[Ru(Cp*) (η2-C2H2(COOEt)2)Cl2] (10). X-ray structures of2,3,4,7, and10 are included.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00807250
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  • 8
    Electronic Resource
    Electronic Resource
    Synthesis and X-ray structures of some mono- and binuclear ruthenium complexes with bisphosphine ligands (1997)
    Springer
    Monatshefte für Chemie 128 (1997), S. 533-540 
    Details
    ISSN: 1434-4475
    Keywords: Ruthenium ; Binuclear complexes ; X-Ray analysis ; Oxidation ; Bisphosphines
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Zusammenfassung Die Komplexe {RuCp*(μ-Cl)}2(μ-dppm) (1) und {RuCp*(μ-Cl2(μ-dppe) (3) wurden durch Umsetzung von [RuCp*(μ3-Cl)]4 mitdppm bzw.dppe dargestellt.1 wird durch AgCF3SO3 zum zweikernigen Komplex [{RuCp*(μ-Cl)}2(μ-dppm)](SO3CF3)2 (2) oxidiert, welcher eine Ru-Ru-Metallbindung aufweist. Unter den gleiche Reaktionsbedingungen zersetzt sich3 zu undefinierten Produkten. Analog zu1 reagiert RuCp* (dmpe)Cl mit AgCF3SO3 zum Ru(III)-Komplex [Ru(Cp*)(dmpe)Cl](SO3CF3) (4) wobei es zu keiner Chloridabspaltung kommt. Von2,3, und4 wurden die Kristallstrukturen bestimmt.
    Notes: Summary The dinuclear complexes {RuCp*(μ-Cl)}2(μ-dppm) (1) and {RuCp*(μ-Cl)}2 (μ-dppe) (3) are obtained by reacting [RuCp*(μ3-Cl)]4 withdppm, anddppe, respectively.1 is readily oxidized with AgCF3SO3, instead of chloride abstraction, to afford the dinuclear complex [{RuCp*(μ-Cl)}2(μ-dppm)](SO3CF3)2 (2) with two metal centers connected by a single Ru-Ru bond. Under the same conditions,3 decomposes to several intractable materials. Similarly to1, RuCp* (dmpe)Cl reacts with AgCF3SO3 to afford the Ru(III) complex [RuCp*(dmpe)Cl](SO3CF3) (4) without no halide abstraction. The crystal structures of2,3, and4 are presented.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00807583
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  • 9
    Electronic Resource
    Electronic Resource
    Zur Oligomeren-Bildung bei der Styrol-Polymerisation (1969)
    Springer
    Naturwissenschaften 56 (1969), S. 515-516 
    Details
    ISSN: 1432-1904
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Chemistry and Pharmacology , Natural Sciences in General
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00601975
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  • 10
    Electronic Resource
    Electronic Resource
    Reaction kinetics of mercaptans with O(3P) atoms (1978)
    Springer
    Naturwissenschaften 65 (1978), S. 154-155 
    Details
    ISSN: 1432-1904
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Chemistry and Pharmacology , Natural Sciences in General
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00440349
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