This PhD thesis is an analysis of the chemical kinetics and oxidation behavior of fuel components via experiments and correlations. First, a number of experimental studies of the reactivity of OH radicals with unsaturated hydrocarbons are performed at temperatures ranging from 294 to 1400 K by OH absorption and laser induced fluorescence techniques in two different reactors: shock tube and flow reactor. It is found that OH has a tendency to add to the unsaturated CC bond, forming a relatively stable adduct. The thermal stability of these adducts is vital for a better understanding of the kinetics of olefins, poly-olefins, alkynes and other unsaturated components in real and surrogate fuel blends. In this work, the reaction rate coefficient of the reaction of hydroxyl radical with many olefins (butenes, pentenes, hexenes), di-olefins (butadienes, and pentadienes) and allyl radical are measured. A strong competition between H-abstraction and OH-addition pathways is seen particularly in the intermediate temperature window of ~ 400 to 900 K. All of these measured elementary reactions give new insights into the chemical kinetics of fuels and allow modelers to improve the predictive capability of their models. Second, measurements of the ignition delay times of propene, isobutene, 2-methylhexane and 2-methylbutanol in air are performed using a high-pressure shock tube. Details about multi-stage ignition and ignition delay dependence on various thermodynamic properties is investigated for these four hydrocarbons. We followed this with a correlation study of ignition delay times of fuel blends and real fuel streams. The main requirement of these correlations is that these should be predictive enough to compete with the predictive capabilities of detailed chemical kinetic models but at a much reduced computational cost. The obtained correlation scheme does not only predict ignition timing during CFD simulations but also other combustion properties such as low-temperature heat release timing and resulting temperature and pressure increases due to cool flame. A discussion on the weak dependence of high-temperature ignition delay times on the composition of real fuels is also presented, where universal Arrhenius type expressions of ignition delay times of gasoline, diesel and jet fuels are given.

Content: Leather industry is one of many traditional, characteristic and ascendant industries. During the development of Leather industry, the problem of a certain the waste of resources and environmental pollution has been yielded. The waste tallow is one of the problems should be solved quickly. Based on the problem of the waste of resources and environmental pollution form the waste tallow during the leather industry, act waste beef tallow from tannery as raw material, detection of its physical and chemical properties, de-colorization, deodorization, amidation, esterification and sulfitation were done successively. Results suggested that the acid value and the saponification value of the waste beef tallow is 45mgKOH/g, 207mgKOH/g respectively. When 6% activated clay was used after 10% hydrogen peroxide, it has the best effect in decolorization and deodorization. When catalyzed by 1% sodium formate, n（ethanolamine）：n （waste beef tallow）is 4:1，the reaction temperature was 130~140oC and time was 2hrs, the acid value and hydroxyl value of the treated beef tallow is 15~30mgKOH/g, about 280mgKOH/g respectively. When the optimum dosage of sodium sulfite is 20%, the fatliquor obtained light yellow and good stability. The sheepskin garment leather fatliquored by this fatliquor is very soft. Take-Away: Modification of a sulfited fatliquor based on waste beef tallow. Application of this sulfited fatliquor. Other methods of modification of waste beef tallow.

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The presence of excess free radicals in the body can result in severe health consequences because of oxidative damage to cells. Spin traps may be used as a probe to examine radical reactions in cells, but there is a need for less toxic and more lipid soluble examples. Melatonin is one of the numerous antioxidants used to scavenge free radicals in the body and reportedly one of the most efficient radical scavengers known. It is relatively nontoxic and easily crosses the lipid bilayer in cell membranes. Melatonin is thought to undergo a multistep oxidation process and this work investigates the potential for it to be used as a spin trap. The presence of electron withdrawing or donating groups added to melatonin may stabilize an intermediate and allow it to function as a spin trap. The essence of this study is to conduct a computational inquiry into the relative stability of melatonin, selected derivatives, and the partial oxidation products formed from the scavenging of hydroxyl radical. To determine this, geometries were optimized for each molecule at the DFT/B3LYP/6-31G(d) and HF/6-31G(d) levels of theory.

Contamination of surface and ground water from industrial wastes and anthropogenic activities represents one of the greatest challenges to the sustainable development of human society. Heterogeneous photocatalysis, a kind of advanced oxidation process characterized by the production of highly oxidative hydroxyl radicals, is a relatively novel subject with tremendous potential in water treatment applications.     The purpose of this research was first to develop feasible hydroxyl radical detection methods, which can be used to evaluate efficiency of photocatalytic process, and second to prepare immobilized TiO2 films with high photocatalytic activities by the sol gel method.     The feasibility of Indigo carmine and phthalic hydrazide as OH-radical probes was investigated. The organic dye Indigo carmine absorbs visual light strongly at 610 nm and its destruction can be monitored conveniently in a spectrophotometer. Results showed that both ·OH and HO2· can bleach Indigo carmine, and the bleaching yield of ·OH was pH independent. The photocatalytic dye bleaching in black light UV illuminated Degussa P25 TiO2 aerated suspensions was then investigated. A strong pH dependency of the bleaching yield was found.  This implies that the quantum yield of OH radical at pH 3 is one fourth compared to that at pH 10. The reaction of the OH radical with phthalic hydrazide will form strongly chemiluminescent 3-hydroxyphthalic hydrazide. Using the more specific phthalic hydrazide as OH radical probe, an even stronger pH dependent quantum yield of OH radical was found. At pH 10 the quantum yield reached the same magnitude as that obtained by using Indigo carmine, whereas the quantum yields at acidic pH were close to zero. However it was found that the addition of phosphate and fluoride anions can substantially enhance the OH radical yield at acidic pH by blocking the adsorption of phthalic hydrazide onto the TiO2 surfaces. Hence the adsorption of phthalic hydrazide to TiO2 is an important factor to consider when this method is used.     Photocatalytic TiO2 films coated on metal plates were prepared by a sol gel method using titanium isopropoxide as TiO2 precursor and isopropanol as solvent. The photocatalytic activity of the obtained films was evaluated by bleaching of indigo carmine at pH 9 under black light UV irradiation. The effect of the molar ratio of isopropanol, water and hydrochloric acid to titanium isopropoxide was studied. It was also shown that the activities of TiO2 films are considerably influenced by calcination temperature, coating cycles and the supporting materials. / Förorening av yt- och grundvatten från industrier och humana aktiviteter utgör en av de största utmaningarna för en hållbar utveckling av det mänskliga samhället. Heterogen fotokatalys, en slags avancerad oxidations process som kännetecknas av att starkt oxidativa hydroxylradikaler produceras, är en relativt ny teknik med stor potential för vattenrening.     Ett syfte med detta licentiatarbete var först att utveckla och genomföra olika metoder för att detektera bildningen av hydroxylradikaler såväl i laboratoriet som i tekniska miljöer. Det andra syftet med arbetet var att syntetisera immobiliserade TiO2 filmer med hög fotokatalytisk effektivitet med en sol-gel metod.     Möjligheten att använda indigokarmin och ftalhydrazid som OH-radikalprob undersöktes. Det organiska färgämnet indigokarmin absorberar synligt ljus starkt vid 610 nm vilket gör att dess nedbrytning lätt kan följas i en spektrofotometer. Resultaten av gammaradiolys visade att båda •OH och HO2• kan bleka indigokarmin och att den blekning som härrör från •OH var oberoende av pH. Fotokatalytisk blekning av indigokarmin med blacklight UV bestrålning av  Degussa P25 TiO2 suspensioner undersöktes sedan. Ett starkt pH-beroende av blekningsutbytet erhölls vilket tolkas som att kvantutbytet av OH-radikaler vid pH 3 är en fjärdedel jämfört med det vid pH 10.     När ftalhydrazid reagerar med OH-radikaler bildas starkt kemiluminiscent 3-hydroxy-ftalhydrazid. Med denna  specifika OH-radikalprob, erhölls ett ännu starkare pH beroende. Vid pH 10 var kvantutbytet i paritet med det som erhölls med indigokarmin, medan kvantutbytet vid lågt pH var nära noll. Tillsats av fosfat-  och fluoridjoner visade sig avsevärt öka OH-radikalutbytet vid lågt pH-värde genom att blockera adsorption av ftalhydrazid på TiO2 ytorna. Adsorptionen av ftalhydrazid på TiO2 är således en viktig faktor när denna metod används.     Fotokatalytiskt verksamma TiO2-filmer på metallplattor framställdes med sol-gel metoden med titan-isopropoxide som TiO2-prekursor och isopropanol som lösningsmedel. Den fotokatalytiska aktiviteten av TiO2-belagda plattor utvärderades genom blekning av indigokarmin vid pH 9 under blacklight UV-bestrålning. Effekten av olika proportioner mellan isopropanol, vatten och saltsyra till titan isopropoxide undersöktes. Det visade sig att denfotokatalytiska aktiviteten av TiO2-plattorna i hög grad påverkades av kalcineringstemperatur, beläggningscykler och materialet i plattorna.

The present study was designed to explore the role of ontogenetic lead (Pb2+) exposure on a putative dopaminergic-nitrergic interaction in the nigrostriatal pathway. Pregnant Wistar rats were given tap water containing 250-ppm lead acetate, for the duration of pregnancy, with regular tap water (without Pb2+) being substituted at birth. Control rats were derived from dams that consumed tap water throughout pregnancy, and had no exposure to Pb2+ afterwards. At 12 weeks after birth in vivo microdialysis of the neostriatum was employed to demonstrate that maternal Pb2+ exposure was without effect on the baseline dopamine (DA) microdialysate concentration as well as amphetamine (AMPH, 1.0 mg/kg i.p.)-evoked release of striatal DA. Also, prenatal Pb2+ exposure did not enhance AMPH- and 7-nitroindazole (neuronal nitric oxide synthase inhibitor) (7-NI, 20 mg/kg i.p.)-induced hydroxyl radical (HO{radical dot}) formation in the striatum, as indicated by analysis of the salicylate spin-trap product 2,5-dihydroxybenzoic acid. However, in rats exposed prenatally to Pb2+, the facilitatory effect of 7-NI on DA exocytosis was attenuated. On the basis of the current study we conclude that maternal Pb2+ exposure distorts the dopaminergic-nitrergic interaction in the nigrostriatal pathway, but without involvement of reactive oxygen species (ROS).

It is well established that low level Pb-exposure is associated with a wide range of cognitive and neurobehavioral dysfunctions in children. In fact, Pb-induced damage occurs preferentially in the prefrontal cerebral cortex, hippocampus and cerebellum - the anatomical sites which are crucial in modulating emotional response, memory and learning. Previously it was also shown that nitric oxide (NO) signaling pathway as well as glutamatergic neurotransmission are both involved in brain development, neurotoxicity and neurodegeneration processes whereas Pb2+ interfere with both. For this reason we investigated the effect of ontogenetic Pb2+ exposure on dopaminergic neurotransmission in the medial prefrontal cortex (mPFC) of rats after amphetamine (AMPH) and/or 7-nitroindazole (7-NI) administration. Furthermore, the possible role of oxidative stress in Pb2+-induced neurotoxicity in prenatally Pb2+-treated rats was explored in the content of hydroxyl radical (HO•) species in mPFC after AMPH and/or 7-NI injection, assessed by HPLC analysis of 2.3-dihydroxybenzoic acid (2.3-DHBA) - spin trap product of salicylate. As shown, the results of this study suggest that Pb2+ exposure during intrauterine life did not substantially affect cortical dopaminergic neurotransmission in adult offspring rats evaluated by means of microdialysis of mPFC and the content of the cortical HO•. It is likely that striatum, nucleus accumbens or other dopamine rich brain areas are more intricately associated with Pb2+ precipitated behavioral, dopamine - dependent impairments observed in mammalians.

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京都大学 / 0048 / 新制・課程博士 / 博士(医学) / 甲第17974号 / 医博第3838号 / 新制||医||1001(附属図書館) / 80818 / 京都大学大学院医学研究科医学専攻 / (主査)教授 羽賀 博典, 教授 坂井 義治, 教授 千葉 勉 / 学位規則第4条第1項該当 / Doctor of Medical Science / Kyoto University / DFAM

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