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The increased popularity of high power microwave systems and the various sources to drive them is the motivation behind the work to be presented. A stand-alone, self-contained explosively driven high power microwave pulsed power system has been designed, built, and tested at Texas Tech University's Center for Pulsed Power and Power Electronics. The system integrates four different sub-units that are composed of a battery driven prime power source utilizing capacitive energy storage, a dual stage helical flux compression generator as the main energy amplification device, an integrated power conditioning system with inductive energy storage including a fast opening electro-explosive switch, and a triode reflex geometry virtual cathode oscillator as the microwave radiating source. This system has displayed a measured electrical source power level of over 5 GW and peak radiated microwaves of about 200 MW. It is contained within a 15 cm diameter housing and measures 2 m in length, giving a housing volume of slightly less than 39 l. The system and its sub-components have been extensively studied, both as integrated and individual units, to further expand on components behavior and operation physics. This report will serve as a detailed design overview of each of the four subcomponents and provide detailed analysis of the overall system performance and benchmarks.

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Soda lime phosphate bioglass-ceramics with incorporation of small additions of TiO2 were prepared in the metaphosphate and pyrophosphate region, using an appropriate two-step heat treatment of controlled crystallization defined by differential thermal analysis results. Identification and quantification of crystalline phases precipitated from the soda lime phosphate glasses were performed using X-ray diffraction analysis. Calcium pyrophosphate (beta-Ca2P2O7), sodium metaphosphate (NaPO3), calcium metaphosphate (beta-Ca(PO3)2), sodium pyrophosphate (Na4P2O7), sodium calcium phosphate (Na4Ca(PO3)6) and sodium titanium phosphate (Na5Ti(PO4)3) phases were detected in the prepared glass-ceramics. The degradation of the prepared glass-ceramics were carried out for different periods of time in simulated body fluid at 37 degrees C using granules in the range of (0.300-0.600 mm). The released ions were estimated by atomic absorption spectroscopy and the surface textures were measured by scanning electron microscopy. Evaluation of in vivo bioactivity of the prepared glass-ceramics was carried through implanting the samples in the rabbit femurs. The results showed that the addition of 0.5 TiO2 mol% enhanced the bioactivity while further increase of the TiO2 content decreased the bioactivity. The effect of titanium dioxide on the bioactivity was interpreted on the basis of its action on the crystallization process of the glass-ceramics.

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A simple, rapid, stability-indicating first-derivative spectrophotometric assay procedure for the determination of the degradation products of acetazolamide is described. The dissolution and kinetics of drug degradation in aqueous buffered solutions were studied using the proposed method. Acetazolamide solution exhibited optimum stability at pH 4. The influences of temperature and sonic energy on the degradation of acetazolamide in 0.01 M NaOH solution were also studied. The results showed first-order reaction kinetics, with a degradation rate constant and degradation half-life of 3.51 x 10(-3) day-1 and 8.23 days, respectively.

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Cimetidine has been determined in the presence of its acid-induced degradation products using a second derivative (D2-) spectrophotometric method (method I) or a colorimetric method (method II). The former is based on D2-value measurement at 216 nm, whilst the latter depends on charge-transfer complexation with dichlorophenol-indophenol. The two methods are proved to be stability indicating, since plots of log C% versus time were linear. The application to cimetidine determination in tablets and ampoules gave good results.

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A computer-assisted method for analysis of multicomponent mixtures by use of conventional absorbance as well as discrete Fourier transforin coefficients (combined trigonometric functions) is presented. The program can store absorbance data (A vs. lambda), process data by convolution with combined trigonometric functions, apply least-squares analysis and solve the resultant simultaneous linear equations, and display data on screen, printer or plotter.

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Third- and fourth-derivative spectrophotometry (3D + 4D), with a diode-array spectrophotometer, has been used for the assay of mixtures of each of isothipendyl hydrochloride (I) and its sulphoxide (II) or dimethothiazine mesylate (III) and its sulphoxide (IV). The parent compounds have been determined by measuring the 3D at 256 nm, 246-256 nm and 256-264 nm and 4D at 250 nm for (I) and 3D at 255 nm or 283 nm and 4D at 257 nm for (III). The sulphoxides have been assayed by measuring the 3D at 285-290 nm and 4D 285-290 nm for (II) and 3D at 305 nm and 4D at 303-310 nm for (IV). Beer's law is obeyed and the detection limits for the proposed 3D and 4D has been calculated. The recovery of these drugs and their sulphoxides in laboratory-made mixture and dosage forms has been reported.

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First (D1) and second (D2) derivative spectrophotometric methods are presented for the determination of clotrimazole after its acid hydrolysis. Mixtures of clotrimazole with azidamfenicol and dexamethasone have been assayed using D2 measurement at 302 nm after acid hydrolysis for clotrimazole, D1 measurement at 288 nm for azidamfenicol, and D1 measurement at 436 nm after reaction with phenylhydrazinium sulfate for dexamethasone. Reproducible results with relative standard deviations of less than 2% are obtained. The proposed method has been successfully applied to the analysis of creams, topical solutions, and vaginal tablets.

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Three 2-component mixtures, namely, dexamethazone-chlorpheniramine maleate, prednisolone-chlorpheniramine maleate, and prednisolone-salicylic acid, have been assayed using their first (D1) and second (D2) derivative spectra in methanol, delta absorption (delta A), and second derivative of delta A (delta D2) spectra in methanol-methanolic HCl. In the first 2 mixtures, chlorpheniramine maleate was determined by measuring its delta D2 value at 278 nm, while dexamethazone and prednisolone were analyzed by measuring their D1 values at 248 nm. Prednisolone and salicylic acid were analyzed in combination by using their respective D2 spectral responses at 272 and 314 nm. The results obtained are reasonably reproducible with a relative standard deviation less than 2%. The method has been successfully applied to the analysis of these drugs in their pharmaceutical formulations.

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A rapid and accurate method for determining acetaminophen and phenacetin in presence of their degradation products is presented. Solutions of these drugs in 0.1N HCl were analyzed by measuring their second derivative spectral response at 295 nm where the degradation products do not interfere. The mean percent recoveries for mixtures of acetaminophen and/or phenacetin with the corresponding degradation products were 100.2 +/- 0.6 and 100.6 +/- 1.1, respectively. The method can be used for assessing the stability of the 2 drugs. The proposed method is also applied to the determination of acetaminophen in tablets and syrups.

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Spectrofluorimetric methods are described for the assay of tetracycline (TC) and anhydrotetracycline (ATC) in combination, without prior separation. The interference from ATC in the TC assay has been corrected for by forming the aluminium complexes of both drugs and measuring the difference in fluorescence at 475 and 418 nm, with excitation at 393 nm. Similarly, measurement of the fluorescence of the magnesium complexes at 525 and 470 nm (excitation at 440 nm) nullifies TC interference in the ATC assay.

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A simple and direct method for the determination of ethinyloestradiol as a minor component in the presence of norethisterone and in oral contraceptive tablets is presented. The method is based on measuring the signal intensity, d delta A/d lambda and d2 delta A/d lambda 2, of the generated first and second derivative spectra of the delta-absorbance curves obtained by measuring solutions in methanol and methanol-sodium hydroxide at certain wavelengths. The method has been applied to the determination of ethinyloestradiol in oral contraceptive tablets, with a coefficient of variation of less than 2%.

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The reactions of chloranil, fluoranil, 2,5 dichlorobenzoquinone and chloranilic acid with some alkaloids on thin layer chromatograms were examined with a view to determine their suitability as visualizing agents. Chloranil and 2,5 dichlorobenzoquinone (each 0.5% w/v in dioxan) were found to be most suitable as they gave coloured reaction products with many alkaloids.

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In dioxan-chloroform medium the acceptor chloranilic acid forms 1:1 molecular complexes with the alkaloids atropine, pilocarpine and strychnine, with maximum absorption at 535, 527.5 and 535 nm respectively. Conformity with Beer's law allows the use of the complexes for the assay of these drugs.

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Two methods, kinetic and titrimetric, based on an electrophilic substitution reaction with bromine, are described for the assay of phenylephrine hydrochloride in nose drops, salicylamide in tablets, and tetracycline hydrochloride in capsules. The kinetic method depends on the linear relationship between concentration of the drug (microgram/mL) and time (s) for nuclear monobromination, indicated by bleaching of the methyl orange acid color. The titrimetric method is based on addition of excess of bromate-bromide with subsequent determination of excess bromine by an iodide-thiosulfate procedure. This method is also used to count the number of bromine atoms necessary for the electrophilic substitution reaction. Preservatives or tablet-capsule bases do not interfere in either method. Recoveries of drugs added to laboratory-prepared samples were good. As indicated by the F-test, the methods are equally reproducible.

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