Library

X
feed icon rss

Your email was sent successfully. Check your inbox.

An error occurred while sending the email. Please try again.

Proceed reservation?

Export
  • 1
    Electronic Resource
    Electronic Resource
    The aggregation in dodecyltrimethylammonium hydroxide aqueous solutions (1995)
    Springer
    Colloid & polymer science 273 (1995), S. 959-966 
    Details
    ISSN: 1435-1536
    Keywords: Hydroxide surfactants ; critical micelle concentration ; aggregation ; cationic surfactants ; micelle charge
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology , Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics
    Notes: Abstract The aggregation of dodecyltrimethylammonium hydroxide (DTAOH) aqueous solutions has been studied by several methods. It is stepwise and four critical points were found. AtC T=(2.51±0.10)×10−4 mol · dm−3 the surface excess becomes zero, atC T=(1.300±0.041)×10−3 mol · dm−3 small aggregates from, which grow with concentration. AtC T=(1.108±0.010)×10−2 mol · dm−3 true micelles form (CMC) and at (3.02±0.28)×10−2 mol · dm−3 the structure of micelles probably changes affecting their properties. The DTAOH micelles are highly ionized (α=0.8) at the CMC, and decreases to reach very small values when the total concentration increases.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00660374
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 2
    Electronic Resource
    Electronic Resource
    The aggregation of aqueous dodecylphosphonic acid in dodecyltrimethylammonium hydroxide mixtures (1996)
    Springer
    Colloid & polymer science 274 (1996), S. 669-677 
    Details
    ISSN: 1435-1536
    Keywords: Dodecanephosphonic acid ; dodecyltrimethylammonium hydroxide ; mixed micelles ; critical micelle concentration ; aggregation
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology , Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics
    Notes: Abstract The aggregation of aqueous dodecylphosphonic acid (DPA) and dodecyltrimethylammonium hydroxide (DTAOH) mixtures was studied by several methods. The behavior of DPA-rich mixtures is close to that of pure DPA. This is probably due to the preservation of the hydrogen-bonded structure of the micellar headgroup layer. The behavior is almost ideal. Betweeny DPA =0.5 and 0.33 (y DPA being the mole fraction of DPA in the surfactant mixture), the hydrogen-bonded structure of the micellar headgroup layer is destroyed. A sort of “micellar azeotrope” is formed, and the maximum of non-ideal interaction between the two surfactants is attained aty DPA =0.4. Fory DPA 〈0.33 the system behaves as a common mixture of a cationic surfactant and a non-ionic one (DPA.2LTA). There is a phenomenon of counterion “condensation” on aggregates at concentrations over the CMC.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00653066
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 3
    Electronic Resource
    Electronic Resource
    The effect of NaOH on dodecyltrimethylammonium hydroxide aggregation in aqueous solutions (1996)
    Springer
    Colloid & polymer science 274 (1996), S. 854-859 
    Details
    ISSN: 1435-1536
    Keywords: Hydroxide surfactants ; critical micelle concentration ; aggregation ; cationic surfactants ; counterion effect
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology , Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics
    Notes: Abstract The aggregation of dodecyltrimethylammonium hydroxide (DTAOH) in aqueous NaOH solutions was studied as a function of NaOH concentration. As in NaOH-free DTAOH aqueous solutions, the surfactant underwent a stepwise aggregation mechanism. Changes in the structure of aggregates produced an increase of the concentration at which premicellar aggregates could solubilize hydrophobic dyes and also in the concentration at which hydroxide inons join the aggregates.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00654743
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 4
    Electronic Resource
    Electronic Resource
    Die partielle Hydrolyse von Phosphorhalogeniden (1958)
    Weinheim : Wiley-Blackwell
    Zeitschrift für anorganische Chemie 294 (1958), S. 224-232 
    Details
    ISSN: 0044-2313
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Die partielle Hydrolyse von POCl3 führt bei stöchiometrischen Verhältnissen zur Dichlorphosphorsäure. Diese Säure und einige ihrer Salze konnten rein dargestellt werden. Bei der weiteren Hydrolyse war die Monochlorphosphorsäure nicht zu fassen, da unter den gewählten Reaktionsbedingungen Kondensationsreaktionen zu Derivaten von Polyphosphorsäuren führten. Die Hydrolyse von PCl3 lieferte trotz Variation der Bedingungen phosphorige bzw. diphosphorige Säure als Hauptprodukte. Daneben tritt eine Disproportionierung in POCl3 und P4O ein. Der Reaktionsmechanismus wird diskutiert.
    Additional Material: 1 Tab.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/zaac.19582940314
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 5
    Electronic Resource
    Electronic Resource
    Zur Reinstdarstellung oligomerer ChlorcyclophosphazeneProfessor Kurt Issleib zum 60. Geburtstage gewidmet (1979)
    Weinheim : Wiley-Blackwell
    Zeitschrift für anorganische Chemie 458 (1979), S. 318-320 
    Details
    ISSN: 0044-2313
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Ultra-Purification of Oligomeric ChlorocyclophosphazenesChlorocyclophosphazenes are obtained usually as a mixture of different ring size oligomers. Isolation of the raw oligomeric species may be performed easily, while their ultrapurification is a rather difficult operation. For special requirements, ultrapure oligomeric chlorocyclophosphazenes may be obtained by a high-yield zone-melting procedure.
    Notes: Die applikativ und theoretisch bedeutenden oligomeren Chlorcyclophosphazene fallen bei den klassischen Syntheseverfahren als Komponenten eines Gemisches verschiedener Ringgrößen an. Während eine Isolierung der einzelnen Spezies in rohem Zustand im allgemeinen keine Schwierigkeiten bereitet, ist ihre Reinstdarstellung nicht unproblematisch. Die manchmal erforderlichen hochgereinigten Verbindungen sind mit geringem Aufwand im Zonenschmelzverfahren zugänglich.
    Additional Material: 1 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/zaac.19794580142
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 6
    Electronic Resource
    Electronic Resource
    Schwingungsspektren und Kraftkonstanten symmetrischer Kreisel. XXI [1]. Das Schwingungs-Rotationsspektrum von CF379Br und CF381Br im Bereich von v2Professor Josef Goubeau zum 80. Geburtstage am 31. März 1981 gewidmet (1981)
    Weinheim : Wiley-Blackwell
    Zeitschrift für anorganische Chemie 474 (1981), S. 74-82 
    Details
    ISSN: 0044-2313
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Vibrational Spectra and Force Constants of Symmetric Tops. XXI. Rovibrational Spectrum of CF379Br and CF381Br in the v2 RegionThe rovibrational spectrum of CF379Br and of natural CF3Br has been recorded in the region of the fundamental v2 near 750 cm-1 in the i.r. with a resolution of 0.04 cm-1. From the analysis of the spectra the values of v0, the anharmonicity constants x23, x25 and x26 as well as B″ and B′ from the J structure have been obtained both for CF379Br and CF381Br. v2 displays Fermi resonance with 2v3 which is located near 700 cm-1.
    Notes: Das Schwingungs-Rotations-Spektrum von CF379Br und natürlichem CF3Br wurde im Bereich der Grundschwingung v2 nahe 750 cm-1 im IR mit einer Auflösung von 0,04 cm-1 aufgenommen. Aus der Analyse der Spektren konnten für CF379Br und CF381Br v0, die Anharmonizitätskonstanten x23, x25 und x26 sowie aus der J-Struktur die Werte B″ und B′ ermittelt werden. v2 steht in Fermi-Resonanz mit 2v3 bei ∼700 cm-1.
    Additional Material: 2 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/zaac.19814740308
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 7
    Electronic Resource
    Electronic Resource
    Chalkogenolat-lonen und ihre Derivate. I. Darstellung und Eigenschaften salzartiger Chalkogenophenolate (1977)
    Weinheim : Wiley-Blackwell
    Zeitschrift für anorganische Chemie 435 (1977), S. 98-102 
    Details
    ISSN: 0044-2313
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Chalcogenolates and their Derivatives. I. Syntheses and Properties of Ionic ChalcogenophenolatesThe syntheses and properties of ionic chalcogenophenolates are described. Using liquid ammonia as solvent the alkali chalcogenophenolates M[EPh] (M = Na, K; E = Se, Te; Ph = C6H5) have been synthesized via reduction of the diphenyl dichalcogenides with alkali metals. Similarly, the tetraphenylphosphonium chalcogenophenolates [Ph4P][EPh] (E = S, Se, Te) have been obtained by reacting alkali chalcogenophenolates with tetraphenylphosphonium chloride.
    Notes: Darstellung und Eigenschaften salzartiger Chalkogenolate werden beschrieben. In verflüssigtem Ammoniak als Lösungsmittel lassen sich die Alkalichalkogenophenolate M[EPh] (M = Na, K; E = Se, Te; Ph = C6H5) durch Spaltung der Diphenyldichalkogenide mit Alkalimetallen, die Tetraphenylphosphoniumchalkogenophenolate [Ph4P][EPh] (E = S, Se, Te) durch doppelte Umsetzung der Alkalichalkogenophenolate mit Tetraphenylphosphoniumchlorid erhalten.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/zaac.19774350113
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 8
    Electronic Resource
    Electronic Resource
    Wasserstoffbrücken-Dimerisation einiger P-oxo-N-hydro-cyclophosphazene (1977)
    Weinheim : Wiley-Blackwell
    Zeitschrift für anorganische Chemie 436 (1977), S. 283-288 
    Details
    ISSN: 0044-2313
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Hydrogen-bonded Dimerisation of Several P-oxo-N-hydro-cyclophosphazenes1,3,3,5,5-Pentamethoxy-1-oxo-2-hydro-cyclotriphosphazadiene and 1,3,3,5,5,7,7-heptamethoxy-1-oxo-2-hydro-cyclo-tetraphosphazatriene are hydrogen-bonded dimers in solutions of low polarity. Partial dissoziation of these dimers occurs e. g. in chloroform. Monomeric and dimeric species may be properly quantitated by infrared spectroscopy in deuterochloroform. Equilibrium constants and dissociation enthalpies were determined.
    Notes: 1,3,3,5,5-Pentamethoxy-1-oxo-2-hydro-cyclotriphosphazadien und 1,3,3-,5,5,7,7-Heptamethoxy-1-oxo-2-hydro-cyclotetraphosphazatrien liegen in Lösungen geringer Polarität als doppelt wasserstoffverbrückte Dimere vor. In Chloroform sind diese teilweise dissoziiert. Monomeres und Dimeres können infrarotspektroskopisch in Deuterochloroform quantitativ erfaßt werden. Gleichgewichtskonstanten und Dissoziationsenthalpien wurden auf diesem Wege ermittelt.
    Additional Material: 2 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/zaac.19774360137
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 9
    Electronic Resource
    Electronic Resource
    Darstellung, Struktur und Temperaturabhängigkeit der Phasenbreite der Phase Ca2-xAs1-xBr1+x und thermisches Verhalten der Verbindung Ca3AsBr3Professor Robert Juza zum 80. Geburtstage am 8. Dezember 1984 gewidmet (1984)
    Weinheim : Wiley-Blackwell
    Zeitschrift für anorganische Chemie 518 (1984), S. 77-86 
    Details
    ISSN: 0044-2313
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Preparation, Crystal Structure, and Temperature Dependence of the Homogeneity Range of the Phase Ca2-xAs1-xBr1+x and Thermal Behaviour of Ca3AsBr3The phase (Ca2-x□x)(As1-xBr1+x) (yellow, NaCl type lattice, x ≙ degree of substitution) was prepared from “Ca3As2” and CaBr2 in different molar ratios in steel ampoules under argon at 900 and 950°C resp. The lattice constant as a function of the composition, the homogeneity range, and dependence of the bromine rich phase boundary on the temperature were determined. The structure was deduced from single crystal X-ray investigation and density measurements at different compositions.The thermal behaviour of Ca3AsBr3 (colourless, isotypic to Mg3NF3, prepared at 850°C) was studied by annealing samples in molybdenum ampoules under argon in the temperature range 900-1250°C and by differential thermal analysis.From the experimental results a section of the phase diagram Ca3As2-CaBr2 was constructed.
    Notes: (Ca2-x□x)(As1-xBr1+x) (gelb, NaCl-Typ, x ≙ Substitutionsgrad) stellte man aus „Ca3As2“ und CaBr2 (unterschiedliche Molverhältnisse) in Stahlampullen unter Argon bei 900 bzw. 950°C dar. Die Abhängigkeit der Gitterkonstante von der Zusammensetzung, der Homogenitätsbereich und die Temperaturabhängigkeit der bromidreichen Phasengrenze wurden ermittelt. Die Struktur bestimmte man durch die röntgenographische Einkristalluntersuchung und durch Dichtemessungen bei unterschiedlichen Zusammensetzungen.Das thermische Verhalten des Ca3AsBr3 (farblos, Mg3NF3-Typ, dargestellt bei 850°C) untersuchte man durch Erhitzen von Proben in Molybdänampullen unter Argon im Temperaturbereich 900 bis 1250°C und durch differenzthermoanalytische Messungen.Mit den experimentellen Ergebnissen wurde ein Ausschnitt aus dem Zustandsdiagramm Ca3As2-CaBr2 konstruiert.
    Additional Material: 3 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/zaac.19845181108
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
Close ⊗
This website uses cookies and the analysis tool Matomo. More information can be found here...