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A Study of Sympathiomimetic Amines, Synthesis of O-Alkylhydroxylamines

Description: Although many sympathomimetic amines have been prepared, the perfect one has not yet been made. Chemists are still attempting to synthesize a selective drug with more prolonged effects and free from side reactions or compensatory vasodilation. With this idea in mind it seemed feasible to prepare a group of O-substituted hydroxylamines.
Date: 1947
Creator: Robbins, Margaret C.
Partner: UNT Libraries

The low-temperature solubility of aniline, the toluidines and some of their N-alkyl derivatives in aviation gasoline

Description: Report presenting testing to determine the solubilities in gasoline at low temperatures of 15 aromatic amines from the NACA exploratory program as antiknock additives. The solubility data is summarized in a table by interpolating or extrapolating experimental results to obtain solubility at -60 degrees Celsius.
Date: June 1944
Creator: Olson, Walter T. & Kelly, Richard L.
Partner: UNT Libraries Government Documents Department

Some Amine Derivatives of 1,4-naphthoquinone

Description: It was the aim of this investigation to prepare derivatives of 1,4-naphthoquinone substituted at the 2- and 3- positions with various amino groups. 2,3-Dichloro-1,4-naphthoquinone was selected as the starting material because of the possibility of replacing the chloro groups in direct substitution reactions with amines.
Date: August 1959
Creator: Cunningham, Robert Gipson
Partner: UNT Libraries

Knock-limited performance of blends of AN-F-28 fuel containing 2 percent aromatic amines 4

Description: Report discussing tests on the effect of 2-percent additions of 13 aromatic amines on the knock-limited performance of 28-R fuel in a CFR engine. The amines tested gave good rich mixture response at standard F-4 operating conditions, but were sensitive to engine severity at lean fuel-air ratios.
Date: December 21, 1944
Creator: Alquist, Henry E. & Tower, Leonard K.
Partner: UNT Libraries Government Documents Department

Knock-limited performance of six aromatic amines blended with a base fuel in a full-scale aircraft-engine cylinder

Description: Report discussing tests to determine the effect of 2-percent additions of six aromatic amines on the knock-limited performance of 28-R fuel. All of the aromatic amine blends increased the performance and power of the base fuel. Different blends performed better at different fuel-air ratios.
Date: April 4, 1945
Creator: Jones, Anthony W.; Bull, Arthur W. & Jonash, Edmund R.
Partner: UNT Libraries Government Documents Department

Ultraviolet absorption spectra of aromatic amines in isooctane and in water

Description: Report discusses the results of a study of the ultraviolet absorption spectra in the 3200 A to 2500 A region of 27 aromatic amines in iscoctane and and in water solutions. Factors that affect the absorption spectra of aromatic amines were investigated, and the spectra in the two different solvents were compared. The main variables affecting the absorption are the nature of the solvent, the purity of the aromatic amines, and photochemical decomposition of the aromatic amines.
Date: November 1945
Creator: Tischler, Adelbert O. & Howard, J. Nelson
Partner: UNT Libraries Government Documents Department

Suitability of 18 aromatic amines for overwater storage when blended with aviation gasoline

Description: Report discussing testing of aromatic amines as antiknock additives, and more specifically the suitability of overwater storage for these fuel blends. 12 aromatic amines of three different concentrations at two temperatures were measured. The chemical properties of the most promising fuel blends are described in more detail and correlations were noted.
Date: June 20, 1945
Creator: Goodman, Irving A. & Howard, J. Nelson
Partner: UNT Libraries Government Documents Department

The effect of six aromatic amines on the preignition-limited performance of 28-R aviation fuel in a CFR engine

Description: Report discussing the results of testing on the suitability of six aromatic amines as fuel additives. Antiknock effectiveness, availability, physical properties, and chemical properties for knock tests were explored. The six aromatic amines were xylidines, cumidines, N-methylxylidines, N-methylcumidines, N-methylaniline, and N-methyltoluidine in 28-R aviation fuel.
Date: May 12, 1945
Creator: Male, Donald W.
Partner: UNT Libraries Government Documents Department


Description: Both the study and the use of extractions with highmolecular-weight amines (including quaternary ammoniums) in organic solution are increasing extensively. While equilibria have been measured in the extraction of an increasing range of acids and Aetal ions, a difficulty remains unresolved in that the amine concentration powerdependence of extraction often indicates a different stoichiometry of the complex existing in the organic phase than do limiting loading and other considerations. Nevertheless, amine extraction serves as a useful tool in studying complexes formed in aqueous systems. Process applications have progressed especially in nitrate and chioride systems, in addition to the sulfate systems first emphasized. Systematic surveys, together with information accruing from process development, have extended the ranges of extractions that can be correlated in usefully generalized patterns, which in turn should accelerate the development of new applications. However, many more areas remain to be surveyed before the many pertinent variables will have been covered. New amines of all classes have become available at commercial, development, or researchsample levels, while a few previously promising amines have become less available. Descriptions and current sources are reviewed. (auth)
Date: November 26, 1963
Creator: Coleman, C.F.
Partner: UNT Libraries Government Documents Department

Making Amines Strong Bases: Thermodynamic Stabilization ofProtonated Guests in a Highly-Charged Supramolecular Host

Description: A highly-charged, cavity-containing supramolecular assembly formed by metal-ligand interactions acts as a host to dramatically shift the effective basicity of encapsulated protonated amine guests. The scope of encapsulated protonated amine and phosphine guests shows size selectivity consistent with a constrained binding environment. Protonation of the encapsulated guests is confirmed by {sup 31}P NMR studies, mass spectrometry studies, and the pH dependence of guest encapsulation. Rates of guest self-exchange were measured using the Selective Inversion Recovery method and were found to correlate with the size rather than the basicity of the guests. The activation parameters for guest self-exchange are consistent with the established mechanism for guest exchange. The binding constants of the protonated amines are then used to calculate the effective basicity of the encapsulated amines. Depending on the nature of the guest, shifts in the effective basicities of the encapsulated amines of up to 4.5 pK{sub a} units are observed, signifying a substantial stabilization of the protonated form of the guest molecule and effectively making phosphines and amines strong bases.
Date: April 16, 2007
Creator: Pluth, Michael D.; Bergman, Robert G. & Raymond, Kenneth N.
Partner: UNT Libraries Government Documents Department

Improved Synthesis of [Si6Cl14]2-Salts as Precursors for Si6H12and other Novel Silanes

Description: The reaction of excess HSiCl{sub 3} with the aforementioned triamines led to the formation of [Si{sub 6}Cl{sub 14}]{sup 2-} containing salts in all instances. The isolated complex salts were characterized using FT-IR and elemental analysis. IR spectra of these compounds showed characteristic Si-H stretching modes around 2100cm{sup -1} due to the hexacoordinate silane cation and Si-Cl active modes near 528cm{sup -1} as a result of the cyclic dianion. Reaction yields and elemental analysis (CHN) of the salts are summarized in a table. The reaction of peralkylated triamines with HSiCl{sub 3} in dry CH{sub 2}Cl{sub 2} gives ionic compounds based upon the tetradecachlorocyclohexasilane dianion. Several substituted triamines(R{sub 2}NC{sub 2}H{sub 4}NR{prime}C{sub 2}H{sub 4}NR{sub 2}where R = R{prime} = Et, {sup n}Pr; R = Et, R{prime}= {sup n}Bu, {sup n}Hexyl, Benzyl) were examined for this reaction and N,N,N{prime},N{prime}-tetraethyl-N{sup {double_prime}}-benzyl-diethylenetriamine produced the best yields of [Si{sub 6}Cl{sub 14}]{sup 2-} salt at 23% based on the amine reagent. This improvement in yield could be attributed to the decreased nucleophilicity of the central amine through increased steric hindrance of the alkyl substituents. The overall consequence of this substituent variation study has revealed new reagents for the synthesis of [Si{sub 6}Cl{sub 14}]{sup 2-} salts and further demonstrated the ability of triamines to efficiently dismutate, complex, and condense chlorosilanes. The increased production of these salts has also opened a route for the study of Si{sub 6}X{sub 12} and its Lewis acid/base adducts.
Date: August 18, 2009
Creator: Anderson, Kenneth; Dai, Xuliang; Nelson, Kendric; Schulz, Doug & Boudjouk, Philip
Partner: UNT Libraries Government Documents Department