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The Use Of Scheffe-Equivalent Equations To Predict Physical Properties Of Neoprene, Cheng Y. Loh
The Use Of Scheffe-Equivalent Equations To Predict Physical Properties Of Neoprene, Cheng Y. Loh
Retrospective Theses and Dissertations
The goal of this study is to find a more organized and directed approach to build models for mixture systems. An attempt is made to generate and then compare Scheffe (mixture) models with those generated by McGee using the ‘conventional’ method for neoprene data. The models are judged on their ability to predict physical properties of neoprene by comparing the following: predicted and actual values by inspection; the calculated % error of prediction; the squared multiple correlation coefficients; adjusted squared multiple correlation coefficients; the Fisher statistic and significance probability. Scheffe models do not have an intercept term and test statistics …
Ion Selective Electrodes Based On Aza- Substituted Crown Ethers, Lisa Ann Wellington
Ion Selective Electrodes Based On Aza- Substituted Crown Ethers, Lisa Ann Wellington
Retrospective Theses and Dissertations
A cation-responsive electrode system has been developed which incorporates aza-substituted crown ethers as ligands. In a novel application, uncomplexed crown ethers were used in the pelletized form for ionic transport. Electrodes have been produced which can be conditioned for a particular ion and following their use, be reconditioned and reused for other ions. Preparation method and lifetime studies are included.
The responses of two crown ethers with plasticizers were evaluated for thirteen representative cations. The concentration range covered in each evaluation was 1 x 10-1 to 1 x 10-7 M. For those ions exhibiting Nernstian or near-Nernstian response, …
Flow Injection And Photometric Determination Of S(Iv) In Rainwater With Pararosaniline, Frank A. Hedgecock
Flow Injection And Photometric Determination Of S(Iv) In Rainwater With Pararosaniline, Frank A. Hedgecock
Retrospective Theses and Dissertations
The photometric pararosaniline (pRA) method for determination of S(IV) has been adapted to flow injection sample processing (FIA). Prominent features of the method include a limit of detection of 0.010 ppm of dissolved sulfur dioxide and a sampling rate of 20 per hour. The concentration range investigated was 0.010 to 0.200 ppm S02. Sequential samples were collected from two rainstorms and SO2 concentrations were measured for 19 samples. The suppression of interference by Cr(III), Mn(II), and Fe(III) using 1,2-cyclohexylenedinitrilotetraacetic acid (CDTA) and ethylenediaminetetraacetic acid (EDTA) was investigated. A comparison of the adapted FIA method and its parent …
New Synthetic Applications Of Enaminoketones, Timothy J. Buck
New Synthetic Applications Of Enaminoketones, Timothy J. Buck
Retrospective Theses and Dissertations
This report discusses research concerning synthetic applications of enaminoketones. The work may be divided into four parts as follows: a) replacement of the dimethylamino group of certain enaminones by other amine groups through a simple procedure; b) formation of 3-alkyl-pyrazoles; c) formation of 2-amino-4-alkyl-pyrimidines; d) synthesis and subsequent reduction of iminium salts. The starting materials (E-1-(N,N-dimethylamino)-1-alkene-3-ones) have been condensed with hydrazine and guanidine to form pyrazoles and pyrimidines, respectively. The same starting materials have been reacted with POCl3 in CH2Cl2 to produce chlorovinyliminium salts. These have then been reacted in situ with reducing agents to produce …