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  • 1
    Electronic Resource
    Electronic Resource
    New York, NY [u.a.] : Wiley-Blackwell
    Journal of Applied Polymer Science 35 (1988), S. 345-362 
    ISSN: 0021-8995
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics , Physics
    Notes: It is shown how the global deformation mechanism in filler-loaded vulcanizates were modified by additional filler-to-matrix bonds. A quantitative description is given in terms of an extended van der Waals treatment including the formulation of a reduced mechanical equation of state. An interpretation of the Mullins softening is presented.
    Additional Material: 6 Ill.
    Type of Medium: Electronic Resource
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  • 2
    Electronic Resource
    Electronic Resource
    New York, NY [u.a.] : Wiley-Blackwell
    Biotechnology and Bioengineering 27 (1985), S. 711-720 
    ISSN: 0006-3592
    Keywords: Chemistry ; Biochemistry and Biotechnology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology , Process Engineering, Biotechnology, Nutrition Technology
    Notes: To simulate production-scale conditions of gluconic acid fermentation by Gluconobacter oxydans, different experimental setups are presented in this study. From the determination of the time constants of a production-scale reactor, it can be concluded that mixing and oxygen transfer are the rate-limiting mechanisms. This results in oxygen concentration gradients which were simulated in a one-compartment reactor in which the oxygen concentration was fluctuated by a fluctuated gassing with air and nitrogen. It could be concluded that only very long periods of absence of oxygen (ca. 180 s) results in lower specific oxygen uptake rates by Gluconobacter oxydans. From scale-down studies carried out in a two-compartment system to simulate a production-scale reactor more accurately, it could be concluded that not only the residence time in the aerated part of the system is important, but the liquid flow in between the different parts of the reactor is also an essential parameter. It could also be concluded that the microorganisms are not influenced negatively by the fluctuated oxygen concentrations with respect to their maximal oxidation capacity. The two-compartment system can also be used for optimization experiments in which the “aerated” compartment was gassed with pure oxygen. From these experiments it was concluded that also a short residence of the cells at high oxygen concentrations diminished the growth and product formation rates. These experiments show the necessity of the scale-down experiments if optimization is carried out. The two-compartment system presented in this study is a very attractive tool for reliable scale-down experiments.
    Additional Material: 9 Ill.
    Type of Medium: Electronic Resource
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  • 3
    Electronic Resource
    Electronic Resource
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 122 (1989), S. 1489-1490 
    ISSN: 0009-2940
    Keywords: Binuclear complexes ; Zirconium ; Group VI metals ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Heterometallic Binuclear Complexes, I.  -  Reactive Zr(IV)-M(0) Compounds (M = Cr, Mo, W) with Bridging Diphenylphosphinocyclopentadienide LigandsReaction of ZrCl2(C5H4PPh2)2 (1) with labile complexes M(CO)3L3 (M = Cr, L = acetonitrile, M = Mo, W, L3 = cycloheptatriene) gives the binuclear compounds ZrCl(μ-Cl)(μ-C5H4PPh2)2M(CO)3 [M = Cr (2), Mo (3), W (4)]. The Cl bridge is readily cleaved by ligands such as CO, MeCN, or P(OMe)3.
    Additional Material: 1 Tab.
    Type of Medium: Electronic Resource
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  • 4
    Electronic Resource
    Electronic Resource
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 118 (1985), S. 403-408 
    ISSN: 0009-2940
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Reactions of 4,5-Diphenyl-1,3,4-oxadiazolylium-2-dicyanmethanide with Methanol and Singlet OxygenThe mesoionic title compound 1 reacts with methanol at room temperature to form methyl benzoate and 2,2-dicyano-2′ -phenyl-acetohydrazide (4), which thermally cyclizes to the amino-pyrazole 5. With photochemically generated singlet oxygen in the presence of methanol, 1, leads to the 1,3,4-oxadiazoline derivative 11 besides HCN and HNCO.
    Type of Medium: Electronic Resource
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  • 5
    Electronic Resource
    Electronic Resource
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 118 (1985), S. 4567-4577 
    ISSN: 0009-2940
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: First 1,4-Dipolar Cycloaddition Reactions of 3,6-Dihydro-6-oxo-1-pyrimidinium-4-olates to 1,2,4-Triazoline-3,5-dionesThe synthesis of some novel representatives of the pyrimidinium-4-olates of type 3 and 7, prepared from amidines 2 or 6 and bis(2,4,6-trichlorophenyl) malonates 1, is described. The representatives 3 or 7, which are substituted at the 5-position, react with the 1,2,4-triazoline-3,5-diones 4 even at room temperature to produce high yields of stable primary adducts 5 or 8, respectively, as a result of a 1,4-dipolar cycloaddition reaction, whereas the betaines 3i,j, which are unsubstituted at the 5-position, react with 4 to give the new betaines 9a,b.
    Notes: Die Synthese einiger neuer Vertreter der Pyrimidinium-4-olate vom Typ 3 und 7 aus den Amidinen 2 bzw. 6 und Malonsäure-bis(2,4,6-trichlorphenylestern) 1 wird beschrieben. Mit den 1,2,4-Triazolin-3,5-dionen 4 reagieren die in 5-Stellung substituierten Vertreter 3 oder 7 bereits bei Raumtemperatur in hohen Ausbeuten zu den stabilen Primäraddukten 5 bzw. 8 als Ergebnis einer 1,4-Dipolaren Cycloaddition, während die in 5-Position unsubstituierten Betaine 3i,j mit 4 die neuen Betaine 9a,b liefern.
    Type of Medium: Electronic Resource
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  • 6
    Electronic Resource
    Electronic Resource
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 119 (1986), S. 762-765 
    ISSN: 0009-2940
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Reactions of 1,2-Dimethyl-3,5-diphenylpyrazolium-4-olate and 3,5-Diphenyl-1,2-dithiolylium-4-olate with Singlet OxygenThe pyrazolium-4-olate 1a and 1,2-dithiolylium-4-olate 1b react with singlet oxygen to produce carbon monoxide and 1,2-dibenzoyl-1,2-dimethylhydrazine (5a) or dibenzoyl disulfide (5b), respectively.
    Type of Medium: Electronic Resource
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  • 7
    ISSN: 0009-2940
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Synthesis of 2,6-Diazabicyclo[2.2.2]oct-7-ene-3,5-diones and 2(1H)-Pyridinones. - A Contribution to the Mechanism and to the Regiochemistry of 1,4-Dipolar Cycloaddition Reactions of New and Known 3,6-Dihydro-6-oxo-1-pyrimidinium-4-olates to Electron-rich and Electron-poor AlkynesThe synthesis of some new representatives of the 3,6-dihydro-6-oxo-1-pyrimidinium-4-olates 3a-f is described. As masked 1,4-dipoles, the betaines 3a-d,g-i combine with bis(diethylamino)ethyne (4a), 1-(diethylamino)-1-propyne (4b), dimethyl acetylenedicarboxylate (4c), or methyl propiolate (4d) to produce the stable heterobicycles 5a-m, whereas the reactions of 3e, f with 4c or 3e with 4d proceed with elimination of phenyl isocyanate to give the 2(1H)-pyridiones 6g, i or 6h, respectively. At higher temperatures, the bicyclic primary adducts 5b-e,k,m also release phenyl isocyanate to form 2(1H)-pyridinone derivatives 6a-f in high yields. In the case of the cycloaddition of 3 to the unsymmetrical alkynes 4b,d the observed regioselectivities are in agreement with the results of MNDO calculations and the FMO and PMO theory.
    Notes: Die Synthese einiger Vertreter der 3,6-Dihydro-6-oxo-1-pyrimidinium -4-olate 3a-f wird beschrieben. Als maskierte 1,4-Dipole vereinigen sich die Betaine 3a-d,g-i mit Bis(diethylamino)ethin (4a), 1-(Diethylamino)-1-propin (4b), Acetylendicarbonsäure-dimethylester (4c) oder Propiolsäure-methylester (4d) zu den stabilen Heterobicyclen 5a-m, während die Reaktionen von 3e, f mit 4c oder 3e mit 4d unter Phenylisocyanat-Eliminierung die 2(1H)-Pyridinone 6g, i bzw. 6h ergeben. Bei höheren Temperaturen spalten auch die bicyclischen Primäraddukte 5b-e,k,m Phenylisocyanat ab und liefern in hohen Ausbeuten 2(1H)-Pyridinon-Derivate 6a-f. Im Falle der Cycloadditionen von 3 an die unsymmetrischen Alkine 4b,d sind die beobachteten Regioselektivitäten mit den Ergebnissen aus MNDO-Rechnungen und der FMO- und PMO-Theorie in Einklang.
    Additional Material: 6 Tab.
    Type of Medium: Electronic Resource
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  • 8
    Electronic Resource
    Electronic Resource
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 121 (1988), S. 2201-2208 
    ISSN: 0009-2940
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Elektronenübertragungen und Konformationsänderungen in 1,n-Diphenylpolyenen1,4-Diphenylbutadien (1), 1,6-Diphenylhexatrien (2) und 1,8-Diphenyloctatetraen (3) werden mit Alkalimetallen reduziert, und die resultierenden paramagnetischen Monoanionen sowie diamagnetischen Dianionen werden durch ESR- bzw. (1H-, 13C-)-NMR-Spektroskopie charakterisiert. Das stereodynamische Verhalten der Ionen wird als Funktion der Kettenlänge, der Ladung und des Gegenions untersucht. Die Reduktion von 1, 2 und 3 dient als Modellexperiment für die Beladung von ausgedehnten linearen Polyenen (Polyacetylenen).
    Notes: 1,4-Diphenylbutadiene (1), 1,6-diphenylhexatriene (2), and 1,8-diphenylocatatetraene (3) are reduced with alkali metals and the resulting paramagnetic monoanions and diamagnetic dianions characterized by ESR and (1H-, 13C-)NMR spectroscopy, respectively. The stereodynamic behavior of the ions is studied as a function of chain length, charge, and counterion. The reduction of 1, 2, and 3 serves as a model experiment for the doping of extended linear polyenes (polyacetylenes).
    Additional Material: 4 Ill.
    Type of Medium: Electronic Resource
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  • 9
    Electronic Resource
    Electronic Resource
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 122 (1989), S. 1623-1627 
    ISSN: 0009-2940
    Keywords: Binuclear complexes ; Molybdenum complexes ; Rhodium complexes ; Sulfur dioxide bridges ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Sulfur(IV) Compounds as Ligands, IX.  -  Binuclear Molybdenum-Rhodium Complexes with Sulfur Dioxide as a Bridging LigandThe hetero-binuclear complexes [MoRhCl(CO)3(μ-SO2)(μ-Ph2E1CH2E3Ph2)(μ-Ph2E2CH2E4Ph2)] (E = P, As, 1-4), [MoRhBr(CO)3(μ-SO2)(μ-Ph2PCH2PPh2)2] (5) and [MoRh(CN)(CO)3(μ-SO2)(μ-Ph2PCH2PPh 2)2] (6) are the first compounds which contain sulfur dioxide as a bridging ligand connected to two metal atoms from different groups of the periodic table. The synthesis starts from Mo(CO)3(NCMe)3 (7), which reacts with the chelating ligands Ph2PCH2PPh2 (dppm), Ph2AsCH2PPh2 (dapm), and Ph2AsCH2AsPh2 (daam) to give the mononuclear precursors Mo(CO)3-(η2-Ph2E1CH2E3 Ph2)(η1-Ph2E2CH2E4 Ph2) (9-12). With [Rh2Cl2(CO)4] these are converted to the binuclear complexes [MoRhCl(CO)4(μ-Ph2E1CH2E3 Ph2)(μ-Ph2E2CH2E4Ph 2)] (15-18). Reversible CO/SO2 exchange finally gives 1-4 and the analogous bromide 5, the cyanide complex 6 is obtained from 1 and NaCN in liquid ammonia.
    Notes: Die heteronuklearen Zweikernkomplexe [MoRhCl(CO)3(μ-SO2)(μ-Ph2E1CH2E3Ph2)(μ-Ph2E2CH2E4Ph2)] (E = P, As, 1-4), [MoRhBr(CO)3(μ-SO2)(μ-Ph2PCH2PPh2)2] (5) und [MoRh(CN)(CO)3-(μ-SO2)(μ-Ph2PCH2PPh 2)2] (6) sind die ersten Verbindungen, in denen Schwefeldioxid als Brückenligand an zwei Metallatome aus verschiedenen Gruppen des Periodensystems gebunden ist. Die Synthese geht von Mo(CO)3(NCMe)3 (7) aus, das mit den Chelatliganden Ph2PCH2PPh2 (dppm), Ph2AsCH2PPh2 (dapm) und Ph2AsCH2AsPh2 (daam) zu den einkernigen Vorstufen Mo(CO)3(η2-Ph2E1CH2E3 Ph2) (η1-Ph2E2CH2E4 Ph2) (9-12) umgesetzt wird. Daraus entstehen mit [Rh2Cl2(CC)4] die Zweikernkomplexe [MoRhCl(CO)4(μ-Ph2E1CH2E3Ph 2)(μ-Ph2E2CH2E4Ph2)] (15-18). Reversibler CO/SO2-Austausch ergibt schließlich 1-4 und das analoge Bromid 5, der Cyanokomplexe 6 wird aus 1 und NaCN in flüssigem Ammoniak erhalten.
    Additional Material: 1 Ill.
    Type of Medium: Electronic Resource
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  • 10
    ISSN: 0018-019X
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Selective oxidations of bis(tricarbonyliron) complexes of methyl (3,7,8-trimethylidenebicyclo[2.2.2]oct-5-en-2-ylidene)methyl ketones 15-17 afforded selectively the tricarbonyl {(1RS,4SR,7SR,8RS)-C,7,8,C-η-[methyl (3,7,8-trimethylidenebicyclo[2.2.2]oct-5-en-(2Z)-2-ylidene)methyl ketone]}iron (12), the corresponding (2E)-derivative 13 and the tricarbonyl{(1RS,2RS,3SR,4SR)-C,2,3,C-η-[methyl (3,7,8-trimethylidenebicyclo[2.2.2]oct-5-en-(2Z)-2-ylidene)methyl ketone]}iron (18). The stereoselectivity of the Diels-Alder reactions of the uncomplexed (Z)- and (E)-hexadienone 12 and 13, respectively, was established. The face of the diene syn with respect to the C(5), C(6) etheno bridge was preferred for the cycloadditions of N-phenyltriazolinedione (NPTAD). In contrast, the reactions of dimethyl acetylenedicarboxylate (DMAD) and methyl propynoate showed a slight preference for addtion to the face of the hexadienones anti with respect to the etheno bridges of 12 and 13. The crystal structure of the adduct 25 resulting from the cycloaddition of NPTAD to 12 is reported.
    Additional Material: 4 Tab.
    Type of Medium: Electronic Resource
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