M.Tech. / A study was undertaken to develop and test the process for the recovery of high purity chromium oxide green from chromium waste. The process developed has a combination of leaching, ion exchange, coagulation, chelation and calcination. Based on the research findings, strong acid cation resin (Purolite 106) and weak acid cation exchange (Lewatit NCP 80) resins were selected for extraction of aluminium Ill ions and chromium Ill ions respectively. The optimal conditions for extraction of chromium (Ill) with ion exchange resins from chromium leachate solution were established taking into account the composition and the parameters of the chromium solution, the resin manufacturer's defined operating conditions and the empirical dependencies established in previous studies on model solutions of chromium (Ill). The effects of pH, compositions and the temperature on the extraction of chromium (Ill) were also examined. The yield of chromium (Ill) from tannery chromium hydroxide solid was about 96-98% after 35 min of phase contact with the sulphuric acid solution. Chromium hydroxide with Cr20 3 content of 88% was achieved by extracting chromium (Ill) with weak acid cation resin. The ferric and calcium ions present in the treated chromium hydroxide product were then removed by soaking the hydroxide cake in 0.1 to 0.2M ethyldiaminetretraacetic (EDTA) acid solution. The final product, chromium oxide green, with a Cr20 3 content of at least 95.14% achieved with the described process.

Oxide scale must be removed before cold drawing wire, otherwise it will cause bad surface quality, inferior die life and many wire ruptures. The nature of oxide scales and the methods of scale removal are reviewed, with particular emphasis on mechanical descaling. This is the major concern of the research, therefore a cantilever bending test has been developed to assess the ease of removal of the scale on commercial steel rod surface in the laboratory. A scanner method and a Finite Element model have been developed to evaluate the critical strain for scale cracking and removal after cantilever bending. Scanning electron microscopy (SEM), together with electron backscattered diffraction (EBSD), energy diffraction spectrum (EDS) and X-ray element mapping analysis, was used to characterize the scale before and/or after bending test. The effects of laying temperature, cooling conditions, ageing time, relative humidity and temperature, and coil positions on scale cracking and removal behaviour were studied. It was found that laying temperature has a larger effect on descalability than cooling conditions. The effect of relative humidity and temperature on descalability depended on a critical holding time. Beyond it, relative humidity and temperature had no further effect on descalability. The higher the environmental temperature, the less the critical holding time. Ageing time had an effect on descalability, but the effect was relatively small. Failure in tension started with first cracks formed at the places with high stress concentration. As tensile strain increased, new cracks formed midway between the existing cracks. Crack spacing stayed uniform but decreased until the scale segments spalled off the rod surface. The crack spacing increased with scale thickness and decreased with strain applied. Scale cracking and spallation mechanisms in compression depended on the relative shear strength of the oxide, the buckling stability of the layer and the relative shear strength of the interface. Spallation always required the propagation of a crack at the interface. The residual sub-layer left on the rod surface of EAF steel after the bending test was identified as magnetite. On the same sample, copper enrichment was found at the scale/metal interface, but within the metal side, and silicon enrichment was found at the scale/metal interface, but within the scale side.

The work in this thesis is concerned with the Green Rusts, which are bluegreen metastable Fe(II) - Fe(III) hydroxy compounds incorporating anions such as SO42-, Cl- or CO3-. These Green Rust compounds (or Fe-GR compounds to distinguish them from the aluminium Green Rusts (Al-GRs) which are isostructural Fe(II) - Al(III) hydroxy compounds) can be produced in a consistent fashion from Fe(II) solutions by the method of induced hydrolysis using Fe(III) gel at pH 7 and under anoxic conditions. A series of sulphate and chloride Fe-GR samples were synthesised, and characterised primarily by the analytical techniques of M8ssbauer spectroscopy, X-Ray diffractometry, infra-red spectroscopy, and vacuum microbalance to measure surface area using the BET N2 adsorption method. For comparison, a few samples of the analogous Al-GR compounds were also synthesised and characterised by the analytical techniques mentioned above. The results in this thesis showed that the systems producing the Fe-GR compounds were of a highly complex nature, and that the amount of precipitate formed depended crucially on the starting conditions. For the 0.1 M FeSO4 system, the GR formed was almost always accompanied by a goethite phase while, for the 0.1 M FeC12 system, pure GR material was only formed at initial Fe(II) - Fe(III) ratios (IFFRs) greater than 6. Any-differences between__the, sulphate and chloride Fe-GRs can. be attributed to the difference in anion-type. X-Ray diffraction in conjunction with electron microscopy and surface area measurements confirm-that the Fe-GRs have a pyroaurite crystal structure, with brucite-like layers formed by a matrix of Fe2+ and Fe 3+ cations and each layer bridged to the other by anions. As far as Messbauer spectroscopy is concerned, the most important diagnostic parameter is the quadrupole splitting (QS) of the Fe(II) doublet measured at 77K for the wet, fresh precipitate (i. e. frozen material). For sul phate Fe-GRs derived from 0.1 M FeSO4 the mean QS is 2.93 ± 0.05 mms-', while for the chloride Fe-GRs derived from 0.1 M FeC12 the mean QS is 2.80 ± 0.05 mms-1. Surface areas for the sulphate Fe-GRs are in the range 40-65 m2. g-1. The products of oxidation and ageing for the Fe-GRs indicate several transformation pathways, especially for the chloride Fe-GRs. Sulphate Fe-GRs converted to goethite on oxidation under both wet and dry conditions, while the chloride Fe-GRs converted to akaganeite on dry oxidation, and to lepidocrocite on wet oxidation. Under both wet and dry anoxic conditions, the chloride Fe-GRs converted to magnetite. In the case of the sulphate Fe-GRs, there was a suggestion that, under the right wet anoxic conditions, the material probably transformed into magnetite. These facts clearly demonstrate that the Fe-GRs are intermediaries in the thermodynamic transformation of Fe in the II oxidation state to Fe in the III oxidation state.

>Magister Scientiae - MSc / Tuberculosis (TB), a deadly disease second to HIV/AIDS, is a global health problem. Diagnosis of active tuberculosis is tedious and requires expensive procedures since there is no recognizable method for sole detection of active TB. Although this is a deadly disease, treatment drug toxicity is also an issue that also causes fatalities in diagnosed patients. Therefore, a rapid sensitive and specific diagnostic method is imperative for TB drug management. In this study spectroscopic and/or electrochemical biosensors were developed for the detection and quantification of TB treatment drugs. The biosensors were constructed with electroactive layers of graphene oxide coupled to silver nanoparticles and/or zinc oxide nanoparticles. These nanoparticles coupled with graphene oxide sheets were covalently attached onto the enzymes such as Cytochrome P450-2D6 to achieve the electrochemical detection of the TB treatment drugs and obtain the required electron transfer between the electrode surface and enzyme. The surface morphology of graphene oxide, nanoparticles as well as the green synthesized nanocomposites were achieved using High-Resolution Transmission Electron Microscopy (HRTEM), Atomic Force Microscopy (AFM), and High- Resolution Scanning Electron Microscopy (HRSEM) while the elemental analysis were obtained using Fourier Transform Infrared Spectroscopy (FTIR), Energy Dispersive X-Ray (EDX), Raman spectroscopy and X-Ray diffraction (XRD). Additionally, the optical properties of the developed nanocomposites where further characterised using Small Angle X-ray Scattering (SAXS), Photoluminescence Spectroscopy (PL) and Ultraviolet Spectroscopy (UV-vis). The electrochemical studies were obtained using cyclic voltammetry (CV) and showed an increase in electron conductivity for the green synthesized zinc oxide nanoparticles coupled with graphene oxide (ZnONPs/GO) and silver nanoparticles coupled with graphene oxide (AgNPs/GO) nanocomposite which was an indication that they were suitable as platforms towards biosensor development. Furthermore, amperometric technique was also used for biotransformation of the TB treatment drugs (Ethambutol and Pyrazinamide) in standard solutions of 0.1 M phosphate buffer (pH 7.0). Furthermore, the sensitivity value of 0.0748 μA/μM was determined for the ethambutol biosensor while a value of 0.1715 μA/μM was determined for the pyrazinamide biosensors. Very good detection limits were obtained for the standard solutions of ethambutol and pyrazinamide where a value of 0.02057 nM was determined for ethambutol at concentration linear range of 50 μM – 400 μM. Additionally, a value of 0.8975 x 10-2 nM was determined for pyrazinamide at the concentration linear range of 100 μM – 300 μM. The determined limit of detections have provided a clear indication that these biosensors have potential of being used in human samples since these values are below the peak serum concentrations of these drugs in TB diagnosed patients as reported in literature. This was further confirmed by the limit of quantification values determined for each biosensor where a value of 0.8975 x 10-2 nM was determined for pyrazinamide and a value of 0.02057 nM was determined for ethambutol.

Avec la prise de conscience du changement climatique et le dévelopement des sources d’énergies renouvelables, une demande accrue pour une électronique de puissance plus fiable et plus efficace apparait. L’électronique de puissance basé sur les semi-conducteurs à grand gap (carbure de silicium, nitrure de gallium et diamant) vont apporter une réelle amélioration par rapport aux systèmes actuels basés sur des composants au silicium. Ces améliorations concernent en particulier une réduction des pertes, une plus grande tension de bloquage, une amélioration de l’efficacité et de la fiabilité des composants, mais aussi en réduisant les exigences thermiques.Le diamant, bien connu pour sa valeur en joaillerie, possède des propriétés électriques et thermiques très utiles pour l’électronique de puissance. Différent type de design et architectures de dispositifs ont été fabriqués à l'aide de diamant semi-conducteur avec ses caractéristiques électriques prometteuses et pouvant ainsi être intégré à des systèmes. Un dispositif Metal-Oxyde-Semiconductor-Field-Effect-Transistor (MOSFET) en diamant pseudo-vertical offre une densité de courant élevée ainsi que des valeurs de résistance et de claquage élevées nécessaires dans les systèmes haute tension.L’objectif de cette thése est de fabriquer le premier MOSFET de puissance diamant à effet de champ pseudo-vertical avec des valeurs de claquage allant jusqu’à 6,5 kV (20 mOhm.cm-2, 200 ° C). Ce travail porte sur la maîtrise des différents processus impliqués dans la réalisation du dispositif en commençant par la caractérisation du substrat cristallin de diamant suivi des croissances épitaxiales, la microfabrication et pour finir la caractérisation de dispositifs.Dans cette thèse, les étapes nécessaires à la réalisation du MOSFET de puissance pseudo-vertical sont présentées ainsi que trois étapes critiques dans la réalisation du dispositif, qui sont les problèmes liés au substrat, la propagation de défauts à travers les différents empilements de couches et la fiabilité de l'oxyde de grille sont abordés. Le choix de substrats de qualité sans défauts de polissage et avec une faibles densités de dislocations est nécessaire pour une croissance de qualité des différentes couches épitaxiées. Différents substrats ont été achetés et caractérisés. Le type de substrat le plus approprié pour la croissance d'épitaxie de qualité est déterminé après caractérisation par topographie à rayons X, mesures de cathodoluminescence et mesures électriques. La propagation des défauts est inévitable durant la croissance des quatre couches d’épitaxie successives nécessaires à la fabrication du transistor MOSFET pseudovertical. L’apparition de défauts peut provenir des différentes concentrations d’impuretés et du type de dopage entrainant une modification du réseau cristallin et la création de contrainte à l'interface. La topographie aux rayons X et les rocking curves ont été utilisées pour étudier les couches après croissance. Une solution pour effectuer une amélioration dans la croissance de cet empilement de couche est proposé.La fiabilité de la grille est généralement source de préoccupation dans les composant de type MOS. Le décalage de la tension de seuil pendant le fonctionnement est une conséquence des charges présentes dans l'oxyde et des états d'interface du dispositif. Un dispositif capacité MOS de type p a été utilisé pour étudier ce phénomène de manière expérimentale. L'influence du recuit post-oxydation à haute température s'est avérée bénéfique pour obtenir des paramètres d'oxyde de grille stables. Le décalage de la tension de bande plate a également été exploré par des mesures de stress en tension.Toutes les étapes nécessaires à la fabrication du transistor ont ainsi été mises au point séparément, et la technologie a été validée par la réalisation et la caractérisation électrique de transistors Metal-Semiconducteur FET et diodes Schottky. / Due to the increase in climate change awareness and development of renewable energy sources, there is an increasing demand for more reliable and efficient power electronics at the point generation, transmision and consumption. Power electronic devices based on wide bandgap semiconductor materials (SiC, GaN and Diamond) will result in substantial improvements in the performance of power electronics systems compared to silicon based devices. They will offer higher blocking voltages, improved efficiency and reliability, as well as reduced thermal requirements.Diamond, though mostly known for its gem value has electrical and thermal properties that are highly beneficial for power electronics. Various device types and device architecture such as diodes, MESFETs and MOSFETS have been made using semiconducting diamond with promising electrical characteristics that could see it incorporated into systems. A pseudo vertical diamond MOSFET device offers possible high current density as well low resistance and high breakdown values needed in high voltage power systems.The aim of this work is to fabricate the first pseudovertical diamond power MOSFET with breakdown values of up to 6.5 kV (20 mOhm.cm-2, 200°C. This work focuses on mastering the series of process involved in the device realization from substrate characterization through epilayer growth to the device microfabrication and the characterization.In this thesis, the detailed steps involved in realizing the pseudovertical power MOSFET has be presented and three critical challenges in the device realization namely substrate related issues, defect propagation through stacked epilayers and the gate oxide reliabiliy has been addressed. The choice of quality substrates free of polishing defects and with low dislocation densities is needed for quality epilayer growth. Different substrates has been procured and characterized. The best substrate type for quality epilayer growth determined after characterization by x-ray topography, cathodoluminescence and electrical measurements have been proposed. Defects propagation was observed in the four stacked epilayer growth needed for the pseudovertical MOSFET transistor. The occurence of defects seems to arise from different impurity concentrations and doping type leading to lattice mismatch and strain in the layers. X-ray topography and rocking curve imaging has been employed to study the grown layers. A method for improved stacked layer growth has also been proposed. The reliability of the gate stack is usually a concern for MOS based devices. The shift in the threshold voltage during operation is a consequence of oxide and interface charges in the device. A p-type MOSCAP device was used to study this phenomenon experimentally. The influence of high temperature post oxidation annealing was found to be beneficial for stable gate oxide parameters. The shift in the flatband voltage has also been monitored through bias stress measurements. The maximum effective charge 9.8E-11 cm-2 as a result of flatband shift was obtained. This value is the same order of magnitude as those observed in state of the art and commercially available SiC devices. All the steps necessary for the transistor fabrication has been developped independently , and technology has been validated by the fabrication and electrical characterization of MESFET and Schottky diodes.

A dissertation submitted to the Faculty of Science, University of the Witwatersrand, Johannesburg, in fulfillment of the academic requirements for the degree of Master of Science. Johannesburg, March 2016. / Zinc oxide (ZnO) continues to receive widespread attention due to its excellent optical and electronic properties; it demonstrates the combined characteristics of high transmittance and electrical conductivity. Despite the tremendous drive for its application in optoelectronic devices, the full nature of the point defects and defect complexes have not been characterised comprehensively. In this work, luminescence characteristics of the intrinsic defects in ZnO thin films and the rare-earth ions Eu3+ and Tb3+ in ZnO powders are investigated under blue-laser excitation. The thin films used in this study were deposited using the radio-frequency magnetron sputtering method over a 2 hour duration under varied power and substrate bias conditions. The powders were synthesized by the chemical bath deposition method with dopant concentrations of 1.0 mol%. Grazing incidence X-ray diffraction (XRD) was used to determine the lattice properties of the samples. Photoluminescence studies were primarily conducted at room temperature (300 K) with the 457.9 nm, 476.5 nm and 488.0 nm laser lines as excitation sources. For the ZnO thin films, XRD patterns of a hexagonal wurtzite structure with a c/a ratio of about 1.60 and a u-parameter of 0.38 were obtained. Photoluminescence measurements show a broad emission band in the 500.0-900.0 nm range, centred at 656.0 nm. Annealed films yielded relatively more intense photoluminescence spectra than the as-prepared films. The intrinsic point defects and defect level transitions responsible for the broad emission are discussed. For the ZnO powders, the XRD patterns of the annealed samples of pristine ZnO, ZnO:Eu3+ and ZnO:Tb3+ are similarly consistent with a hexagonal wurtzite ZnO phase. Energy dispersive spectroscopy (EDS) confirmed the presence of the Eu3+ and Tb3+ dopants in the respective ZnO host while scanning electron microscopy (SEM) measurements showed the morphology of the sample powders. Photoluminescence spectra of pelletized samples, obtained in the 460.0-900.0 nm range, exhibit relatively intense Eu3+ and Tb3+ emission bands superimposed on a broad emission background. The RE3+ emission bands are attributed to the 5D0 → 7FJ (J = 0, 1, 2, 3, 4) and the 5D4 → 7FJ (J = 0, 1, 2, 3, 4, 5, 6) electronic transitions of Eu3+ and Tb3+, respectively, while the background emission is attributed to intrinsic defects. Crystal-field energy levels for the Eu3+ ion and the Tb3+ ion occupying a C3v symmetry site were deduced from fitting Gaussian curves to the RE3+ emission bands. Possible channels for transfer of energy from the intrinsic defects to Eu3+ and Tb3+ are discussed. / LG2017

Thesis (M.Sc.(Engineering)--University of the Witwatersrand, Faculty of Engineering and the Built Environment, School of Chemical and Metallurgical Engineering, 2012,. / The objective of this research was to improve alumina (Al2O3) mechanical and electrical properties by reinforcement using multi-walled carbon nanotubes (MWCNTs) and titanium carbide (TiC). The objective of the study was achieved with interesting and challenging difficulties along the way. The MWCNTs were initially coated with boron nitride (hBN) in order to improve the Alumina-CNTs interface which was previously discovered to be weak and also to protect them from reacting with Al2O3 during sintering. The coating of CNTs with hBN was done using nitridation method. This method was unsuccessful since it was not possible to coat each CNT individually. Dispersing hBN coated CNTs proved to be impossible without pealing the off the hBN coating. The “flaking off “of the hBN coating from the CNTs revealed that the CNT-hBN interface was weak; therefore uncoated CNTs were used for this study. The starting powders (Al2O3, TiC and CNTs) were individually dispersed before they were mixed together. TiC and Al2O3 were dispersed using an ultrasonic probe which was done successfully. The CNTs were dispersed by an ultrasonic probe and then attritor milled with the use of polyvinylpyrolidone (PVP) as a dispersant. The dispersed Al2O3 and TiC (30 wt%) powders were mixed in a planetary ball mill. The composite powder was sieved and sintered using SPS with temperature and pressure programmed to be 1700˚C, 35MPa respectively. In making the Al2O3+CNT composite powder, the already dispersed Al2O3 and CNTs (1 wt%) were mixed in a planetary ball mill, after sieving the powder it was sintered using SPS at 1600˚C, 35MPa (programmed conditions). Lastly in making the Al2O3+CNT+TiC composite, the already dispersed TiC, CNTs and Al2O3 were all mixed in a planetary ball mill, after sieving it was sintered using SPS at 1650˚C, 35MPa (programmed conditions). For comparison of properties, dispersed monolithic Al2O3 was also sintered using SPS at 1600˚C, 35 MPa. The density results showed that the monolithic Al2O3 was 99.8% dense, , Al2O3+CNTs was 99.4%, Al2O3+TiC+CNTs was 99.2% and Al2O3+TiC sample was 99.0%. The mechanical properties of the samples were measured using the indentation method. The hardness and fracture toughness of the samples were; Al2O3= 3.3MPa√m (17 GPa), Al2O3+CNTs = 4.2MPa√m (18 GPa), Al2O3+TiC = 4.8 MPa√m (23 GPa) and Al2O3+TiC+CNT= 5.0 MPa√m (23 GPa). The electrical properties showed that incorporating CNTs and TiC into Al2O3 improved Al2O3 electrical conductivity. The measured electrical conductivity of the ceramic samples were; Al2O3 iii ≈ 0 Sm-1, Al2O3+CNTs= 30 S.m-1, Al2O3 +TiC + CNTs = 6855 S.m-1 and Al2O3+TiC = 9664 S.m-1. The CNTs improved Al2O3 mechanical properties slightly inhibiting grain growth by pinning the grain boundary movement and also by crack bridging. The Al2O3 electrical conductivity was increased by the CNTs network that was located along the alumina grain boundaries. The TiC improved Al2O3 mechanical properties slightly inhibiting grain growth and through crack deflection mechanism. The addition of TiC into Al2O3 increased the electrical conductivity by serving as a conducting continuous secondary phase. The results show that the CNT-hBN interface is weak. The addition of CNTs and TiC into monolithic Al2O3 slightly improved its mechanical and electrical properties but it density was slightly compromised. CNTs and TiC slightly improved monolithic alumina hardness by in inhibiting Al2O3 grain growth and the fracture toughness through crack deflection and crack bridging mechanisms. The CNTs network located at the Al2O3 grain boundaries not only aided in improving Al2O3 hardness but also served as transport medium for electrons hence increasing the Al2O3 electrical conductivity. Addition of TiC into Al2O3 increased its electrical conductivity by conducting electrons from one TiC grain to the adjacent grain. The large increase in electrical conductivity upon addition of TiC is due to the presence of a continuous TiC phase within Al203.

No description available.

Although the terrestrial flux of solar energy is enough to support human endeavors, storage of solar energy remains a significant challenge to large-scale implementation of solar energy production. One route to energy storage involves the capture and conversion of sunlight to chemical species such as molecular hydrogen and oxygen via water splitting devices. The oxygen evolution half-reaction particularly suffers from large kinetic overpotentials. Additionally, a photoactive material that exhibits stability in oxidizing conditions present during oxygen evolution represents a unique challenge for devices. These concerns can be potentially addressed with a metal oxide photoanode coupled with efficient water oxidation electrocatalysts. Despite decades of research, structure-composition to property relationships are still needed for the design of metal oxide oxygen evolution materials. This dissertation investigates transition metal oxide materials for the oxygen evolution portion of water splitting devices. Chapter I introduces key challenges for solar driven water splitting. Chapter II elucidates the growth mechanism of tungsten oxide (WOX) nanowires (NWs), a proposed photoanode material for water splitting. Key findings include (1) a planar defect-driven pseudo-one-dimensional growth mechanism and (2) morphological control through the supersaturation of vapor precursors. Result 1 is significant as it illustrates that common vapor-phase syntheses of WOX NWs depend on the formation of planar defects through NWs, which necessitates reconsideration of WOX as a photoanode. Chapter III presents work towards (1) single crystal WOX synthesis and characterization and (2) WOX NW device fabrication. Chapter IV makes use of the key result that WOX NWs are defect rich and therefore conductive in order to utilize them as a catalyst scaffold for oxygen evolution in acidic media. Work towards utilizing NW scaffolds include key results such as stability under anodic potentials and strongly acidic conditions used for oxygen evolution. Chapter V includes work characterizing nickel oxide/oxyhydroxide oxygen evolution catalysts at near-neutral pH. Key findings include (1) previous reports of anodic conditioning resulting in greater catalytic activity are actually due to incidental incorporation of iron impurities from solution and (2) through intentional iron incorporation via electrochemical co-deposition, catalytic activity is increased ~50-fold over Fe-free catalysts. This dissertation contains previously published coauthored material.

by Chan Yee Man Elaine. / Thesis (M.Phil.)--Chinese University of Hong Kong, 1995. / Includes bibliographical references (leaves 130-143). / Abstract --- p.I / Acknowledgements --- p.III / Abbreviations --- p.IV / Objectives of the study --- p.VII / Table of Contents --- p.VIII / Chapter Section 1 --- Introduction --- p.1 / Chapter 1.1 --- Necrosis vs Apoptosis --- p.2 / Chapter 1.2 --- Cell Death by Apoptosis --- p.4 / Chapter 1.3 --- The Biochemistry of Nitric Oxide --- p.9 / Chapter 1.4 --- Mechanisms of NO Action --- p.14 / Chapter 1.5 --- Signal Transduction Pathways to Apoptosis --- p.17 / Chapter 1.5.1 --- Regulation by Ca2+ --- p.17 / Chapter 1.5.2 --- Protein Kinase C --- p.20 / Chapter 1.5.3 --- cAMP --- p.21 / Chapter 1.5.4 --- Protein tyrosine kinase --- p.21 / Chapter 1.5.5 --- Ceramide --- p.22 / Chapter 1.5.6 --- pH --- p.23 / Chapter 1.5.7 --- Oxygen Radicals --- p.23 / Chapter 1.5.8 --- Anchorage Dependence and Extracellular Matrix --- p.24 / Chapter Section 2 --- Materials and Methods --- p.27 / Chapter 2.1 --- Materials --- p.28 / Chapter 2.1.1 --- Animal --- p.28 / Chapter 2.1.2 --- Cell line --- p.28 / Chapter 2.1.3 --- "Culture media, buffers and chemicals" --- p.28 / Chapter 2.1.4 --- Dye solutions --- p.30 / Chapter 2.1.5 --- Reagents and buffers for polyacrylamide gel electrophoresis (PAGE) --- p.31 / Chapter 2.1.6 --- Reagents and buffers for Western blotting --- p.32 / Chapter 2.1.7 --- Reagents and buffers for agarose gel electrophoresis --- p.33 / Chapter 2.2 --- Methods --- p.35 / Chapter 2.2.1 --- Cell culture --- p.35 / Chapter 2.2.2 --- [3H]-Thymidine incorporation --- p.35 / Chapter 2.2.3 --- MTT assay --- p.36 / Chapter 2.2.4 --- Determination of NO by Griess assay --- p.36 / Chapter 2.2.5 --- Observation of apoptotic morphology of cells by confocal laser scanning microscopy (CLSM) --- p.37 / Chapter 2.2.6 --- Determination of cell death induced by NO producing drugs --- p.38 / Chapter 2.2.7 --- Determination of cell death induced by Concanavalin A --- p.38 / Chapter 2.2.8 --- Determination of effect of nitric oxide synthase (NOS) inhibitor on cell death induced by Con A --- p.39 / Chapter 2.2.9 --- Determination of the requirement of Ca2+ in cell death induced by NO producing drugs --- p.39 / Chapter 2.2.10 --- Determination of the requirement of cGMP in cell death induced by NO producing drugs --- p.40 / Chapter 2.2.11 --- Determination of cell death induced by PKC activation and depletion --- p.40 / Chapter 2.2.12 --- Determination of effect of PKC depletion on cell death induced by NO producing drugs and Con A --- p.41 / Chapter 2.2.13 --- Observation of immunofluorescence by confocal laser scanning microscopy --- p.41 / Chapter 2.2.14 --- Preparation of protein samples for PAGE --- p.42 / Chapter 2.2.15 --- Polyacrylamide gel electrophoresis --- p.43 / Chapter 2.2.16 --- Western blotting of PKC --- p.44 / Chapter 2.2.17 --- Preparation of DNA samples from cells --- p.46 / Chapter 2.2.18 --- Agarose gel electrophoresis of DNA --- p.47 / Chapter 2.2.19 --- Statistical analysis --- p.48 / Chapter Section 3 --- Results --- p.49 / Chapter 3.1 --- Induction of apoptosis in macrophages by NO producing drugs --- p.50 / Chapter 3.2 --- Apoptosis induced by NO producing drugs was caused by NO --- p.54 / Chapter 3.3 --- Signal transduction pathways to the NO-induced cell death in macrophages --- p.66 / Chapter 3.3.1 --- Calcium ion --- p.66 / Chapter 3.3.2 --- cGMP --- p.68 / Chapter 3.3.3 --- Protein kinase C --- p.71 / Chapter 3.4 --- Induction of apoptosis by Con A --- p.89 / Chapter 3.5 --- Tubulin structure in Con A-treated cells --- p.94 / Chapter 3.6 --- Nitric oxide and Con A-induced cell death in macrophages --- p.96 / Chapter 3.7 --- Effect ofNOS inhibitor on cell death induced by Con A --- p.102 / Chapter 3.8 --- Involvement of PKC in the Con A-induced cell death in macrophages --- p.106 / Chapter Section 4 --- Discussion --- p.114 / Chapter 4.1 --- Induction of apoptosis in macrophages by NO producing drugs --- p.118 / Chapter 4.2 --- Signal transduction pathways to the NO-induced cell death in macrophages --- p.120 / Chapter 4.2.1 --- Ca2+ ion --- p.120 / Chapter 4.2.2 --- cGMP --- p.120 / Chapter 4.2.3 --- Protein kinase C --- p.121 / Chapter 4.3 --- Induction of apoptosis by Con A --- p.124 / Chapter 4.4 --- Tubulin structure in Con A-treated cells --- p.124 / Chapter 4.5 --- Nitric oxide and Con A-induced cell death --- p.125 / Chapter 4.6 --- Effect ofNOS inhibitor on cell death induced by Con A --- p.125 / Chapter 4.7 --- Involvement of PKC in the Con A-induced cell death in macrophages --- p.127 / Chapter Section 5 --- Bibliography --- p.129 / References --- p.130