Dimethylamine (DMA), in addition to the alkaloids hordenine and gramine, has been suggested as a potential precursor of nitrosodimethylamine (NDMA) in malt. Analytical procedures were adopted and applied to extract and quantify DMA from malt, green malt, malt roots and raw barley. Ground malt was extracted at room temperature with 0.1 N HC1, and the extract was derivatized with 1% pentafluorobenzoyl chloride in benzene. After purification, the derivatized DMA was quantitated by gas chromatography with a thermionic N-specific detector. The method yielded a 96.3 per cent recovery for DMA, and exhibited a linear relationship between DMA concentration and GC peak height within a given range. The identity of the DMA derivative was confirmed by mass spectrometry. Commercial barley samples of 4 and 5-day germination of Klages variety were analyzed. The mean value for the 4-day germination Klages was 4.9, and for the 5-day, 11.7 μg/gm. The DMA level of 5-day germination Klages were significantly higher than the 4-day (P < 0.05). Levels of DMA in samples at each stage of the malting process were determined. DMA was found with a mean and range of 0.9 (0.6- 1.0); 0.6 (0.5-0.6); 11.6 (8.2-17.7); 513 (396-762); 5.9 (4.8-6.6); and 607 μg/gm (.571-637 μg/gm) on a dry weight basis for, respectively, raw barley, steeped barley, green malt, green malt roots, kilned malt and kilned malt roots. It was found that roots contained the highest levels of DMA. These results indicate that DMA is biosynthetically formed during germination. The nitrosation of 5 varieties of green and kilned malts (Winter, Morex, Klages, Piroline and Steptoe) was carried out to determine the significance of DMA as a precursor for NDMA. The amount of NDMA from DMA was compared to the amounts of NDMA from hordenine and gramine for each sample. In every sample the amount of NDMA from DMA was larger than the combined amount of NDMA from hordenine and gramine. The results strongly suggest that DMA is the primary precursor of NDMA in malt. / Graduation date: 1985

Declining amphibian populations in association with an incidence of deformities have been observed globally. These observations have alarmed the scientific community as well as the general public. Potential causes include exposure to pesticides; therefore two experiments were performed to test the sublethal effects of the herbicide 2,4-dichlorophenoxyacetic acid (2,4-D) on tadpoles of the wood frog (<i>Rana sylvatica</i>). Wood frog tadpoles in the first experiment were exposed to 2,4-D amine at 0.1, 1.0 and 100 ug/L in outdoor microcosms. Morphometric measures (total length, snout-vent length (SVL) and wet weight) were taken at metamorphic climax. Deformities and circulating hormone concentrations (corticosterone - CORT) were also assessed. Results showed that though tadpoles were exposed to various concentrations of 2,4-D throughout their aquatic life, there were no treatment differences associated with any of the endpoints except for total length (p = 0.023). Total length during metamorphosis was highly variable. Although statistically significant, biological significance was questionable. The second experiment was conducted in the field using natural ponds. The experimental groups included forested ponds (removed from pesticide exposure), agricultural ponds (potentially exposed) and treated agricultural ponds (intentionally treated with 2,4-D to achieve a concentration of 10 ug/L). Relatively rapid degradation of 2,4-D occurred in all treated ponds. The mean half-life was 8.0 + 5.5 days. In spite of the degradation, 2,4-D was present in the ponds until tadpoles metamorphosed. Similar endpoints including morphometric measures, as well as deformities and plasma CORT hormone were determined. In addition, total lipid and total protein (of the carcass) were also measured. Unlike the microcosm study, statistically significant differences were observed in SVL, wet weight and total protein although the differences may have been unrelated to 2,4-D exposure. The metamorphs sampled from the forested ponds were smaller in SVL (23% shorter) and wet weight (58% lighter) (p < 0.029) relative to the other two groups. Total protein in the metamorphs from the forested ponds was 22% lower than that of the agricultural ponds (p = 0.020). Reduced hormonal response to acute stress (p = 0.001) was found in metamorphs of the forested ponds compared to those of the other two groups (66% lower response). Herbicide exposure may have induced low level stimulation of growth (a positive impact on the exposed animals), as well as a possible elevation of baseline corticosterone, in the agricultural and treated metamorphs or there may have been a negative stressor present in the forested pond environment. It is not possible to identify the specific factors that were involved. It is unclear if 2,4-D affected the growth and development of wood frog tadpoles.

Declining amphibian populations in association with an incidence of deformities have been observed globally. These observations have alarmed the scientific community as well as the general public. Potential causes include exposure to pesticides; therefore two experiments were performed to test the sublethal effects of the herbicide 2,4-dichlorophenoxyacetic acid (2,4-D) on tadpoles of the wood frog (<i>Rana sylvatica</i>). Wood frog tadpoles in the first experiment were exposed to 2,4-D amine at 0.1, 1.0 and 100 ug/L in outdoor microcosms. Morphometric measures (total length, snout-vent length (SVL) and wet weight) were taken at metamorphic climax. Deformities and circulating hormone concentrations (corticosterone - CORT) were also assessed. Results showed that though tadpoles were exposed to various concentrations of 2,4-D throughout their aquatic life, there were no treatment differences associated with any of the endpoints except for total length (p = 0.023). Total length during metamorphosis was highly variable. Although statistically significant, biological significance was questionable. The second experiment was conducted in the field using natural ponds. The experimental groups included forested ponds (removed from pesticide exposure), agricultural ponds (potentially exposed) and treated agricultural ponds (intentionally treated with 2,4-D to achieve a concentration of 10 ug/L). Relatively rapid degradation of 2,4-D occurred in all treated ponds. The mean half-life was 8.0 + 5.5 days. In spite of the degradation, 2,4-D was present in the ponds until tadpoles metamorphosed. Similar endpoints including morphometric measures, as well as deformities and plasma CORT hormone were determined. In addition, total lipid and total protein (of the carcass) were also measured. Unlike the microcosm study, statistically significant differences were observed in SVL, wet weight and total protein although the differences may have been unrelated to 2,4-D exposure. The metamorphs sampled from the forested ponds were smaller in SVL (23% shorter) and wet weight (58% lighter) (p < 0.029) relative to the other two groups. Total protein in the metamorphs from the forested ponds was 22% lower than that of the agricultural ponds (p = 0.020). Reduced hormonal response to acute stress (p = 0.001) was found in metamorphs of the forested ponds compared to those of the other two groups (66% lower response). Herbicide exposure may have induced low level stimulation of growth (a positive impact on the exposed animals), as well as a possible elevation of baseline corticosterone, in the agricultural and treated metamorphs or there may have been a negative stressor present in the forested pond environment. It is not possible to identify the specific factors that were involved. It is unclear if 2,4-D affected the growth and development of wood frog tadpoles.

El texto completo de este trabajo no está disponible en el Repositorio Académico UPC por restricciones de la casa editorial donde ha sido publicado. / Water-resistant MOF-235 was used to adsorb N,N-dimethylamine (DMA) from aqueous solutions. It was synthesized from terephthalic acid and FeCl3.6H2O under air-free conditions and characterized by its crystalline structure, functional groups and temperature resistance. The kinetic data results were best adjusted to the pseudo-second order model (R2>0.963). The best-fit isotherm, Langmuir model, suggested the adsorption of DMA is localized on homogenously distributed active sites on the surface. This fit was confirmed by the value of β = 1 on the Redlich-Peterson model. Our study suggests that the manipulation of novel materials such as MOF-235 promises new avenues for water treatment solutions. Schematic structure of MOF-235 and its application as adsorbent. / Revisión por pares

The research addresses two groups of reactions: chlorine atom reactions with fluorinated propenes and methyl amines. Most of the reactions were studied over a range of temperature and pressure with the goals of (i) assessing the potential importance of the reactions in atmospheric chemistry and (ii) obtaining kinetic and thermochemical information of fundamental physical–chemical interest. In the studies reported herein, laser flash photolysis (LFP) was coupled with time resolved atomic resonance fluorescence (RF) spectroscopic detection of chlorine atoms to investigate chlorine atom kinetics.

La dégradation photocatalytique de deux amines, la méthylamine (MA) et la diméthylamine (DMA), a été étudiée en présence de TiO2 Degussa P25. Différents paramètres ont été étudiés: l'adsorption à l’obscurité et sous UV, la photolyse, les cinétiques de dégradation, l'effet du pH, l'effet de la nature et de l'intensité du flux photonique ainsi que les voies de dégradation de la MA et DMA.A l’obscurité, le taux de recouvrement des groupes OH est similaire pour la MA et DMA. Sous UV, ce taux devient deux fois plus élevé pour la MA. Les réactivités de MA et DMA sont directement corrélées à leur adsorption sous UV. Les atomes d'azote sont principalement décomposés en ammonium. Le nitrite a été également détecté, mais rapidement oxydé en nitrate. À pH basique, l'hydrolyse photo‐assisté et l'attaque de OH• sur l’atome N augmente. DMA est essentiellement transformé en MA. Les analyses du Carbone Organique Total (COT) montrent la présence de produits finaux contenant de l’azote difficilement minéralisables. Nous avons montré que, quelle que soit l'énergie des photons (UV‐A ou UV‐B), le rendement quantique reste constant et égal à 0,033.L'inactivation photocatalytique de E. coli en présence de la lumière solaire naturelle en absence (SODIS) et en présence de différents catalyseurs a été étudiée. L'effet de la température sur l'inactivation de E. coli a été aussi étudié. Les résultats ont montré que l’addition des différents types de catalyseurs accélère l'effet bactéricide du rayonnement solaire. Aucun phénomène de reviviscence bactérien n’a été observé après l'arrêt de l'exposition solaire durant au moins 72 heures. Seulement les ions ammonium et potassium ont été détectés au cours de l'inactivation de E. coli en accord avec la perforation de la membrane et l’oxydation des protéines. / The photocatalytic degradation of two amino‐compounds, methylamine (MA) and dimethylamine (DMA) was investigated in the presence of UV‐irradiated TiO2 aqueous suspensions. Different parameters were studied: adsorption under dark and UV conditions, photolysis, kinetics of degradation, effect of pH, effect of the nature and intensities of photonic flux and finally the chemical pathway MA and DMA degradation.While, the percentage of covered OH in the dark was equal for MA and DMA, it becomes twice higher for MA under UV. The reactivity of MA and DMA is directly correlated with the adsorption under UV. The nitrogen atoms were decomposed mainly to ammonium. Nitrite was also formed but was rapidly oxidized to nitrate. At basic pH, photo assisted hydrolysis and the attack of OH• on N‐atom increase. DMA is mainly transformed to MA. Total Organic Carbon (TOC) analysis show the presence of final slightly mineralised intermediate compounds containing nitrogen atom. We shown that, whatever the energy of photons (UV‐A or UV‐B), the same quantum yield equal to 0.033 was obtained.The photocatalytic inactivation of E. coli under natural solar irradiation in the absence (SODIS) as well in the presence of different concentrations of varied photocatalysts has also been investigated. The effect of temperature on E. coli inactivation was studied. Results show that the additions of any types of catalyst to the water accelerate the bactericidal action of solar irradiation and leads to a total disinfection. No bacterial regrowth was observed during the subsequent dark period. Ammonium and potassium ions were formed during E. coli inactivation in agreement with the membrane perforation and the oxidation of proteins.

Amine boranes have recently been considered as solid hydrogen storage materials with high capability of hydrogen storage. Dimethylamine borane is one of the promising amine boranes with high theoretical gravimetric capacity of 16.9 wt%. Dimethylamine borane can undergo dehydrogenation only in the presence of a suitable catalyst at moderate temperature. In this project, throughout the dehydrogenation of dimethylamine borane (DMAB), the catalytic activity of ruthenium(III) acetylacetonate was examined for the first time. During the catalytic reaction, formation of a new in-situ ruthenium(II) species, [Ru{N2Me4}3(acac)H], is observed. Mercury poisoning experiment indicates that the in-situ ruthenium(II) species is a homogeneous catalyst in the dehydrogenation of dimethylamine borane. Kinetics of catalytic dehydrogenation of dimethylamine borane starting with ruthenium(III) acetylacetonate was investigated depending on catalyst concentration, substrate concentration and temperature. As a result, the hydrogen generation rate was found to be first-order with respect to catalyst concentration and zero-order regarding the substrate concentration. Besides, evaluation of the kinetic data yielded that the activation parameters for dehydrogenation reaction: the activation energy, Ea = 85 &plusmn / 2 kJ&bull / mol-1 / the enthalpy of activation, DH# = 82 &plusmn / 2 kJ&bull / mol-1 and the entropy of activation / DS# = -85 &plusmn / 5 J&bull / mol-1&bull / K-1. Additionally, before deactivation, [Ru{N2Me4}3(acac)H] provides 1700 turnovers over 100 hours in hydrogen evolution from the dehydrogenation of dimethlyamine borane. [Ru{N2Me4}3(acac)H] complex formed during the dehydrogenation of dimethylamine borane was isolated and characterized by UV-Visible, FTIR, 1H NMR, and Mass Spectroscopy. The isolated ruthenium(II) species was also tested as homogeneous catalyst in the dehydrogenation of dimethylamine borane.

The potential antimalarial and anticancer effect of molecules containing 1,10-phenanthroline skeleton has been suspected on several previous studies. It is why the goal of this project is to synthesize novel 1,10-phenanthrolines and cyclic analogs. The originality of this project is the synthesis way of these novel compounds. Indeed, these structures will be obtained through an original redox approach developed in the SMITH laboratory using the tetrakis(dimethylamino)ethylene (TDAE) reagent.      The TDAE is an electron rich organic molecule which is an effective reducing agent capable of generating an anion from halogenated derivatives under mild conditions via a single electron transfer (SET). From the different substrate we will work with, the TDAE will generate an anion which will be additioned on the 1,10-phenanthroline-5,6-dione. These different substrates will be aromatic and heterocyclic nitro-benzylic, and quinonic derivates as well as bromodifluoromethyl heteroarylated substrates. A one pot two step (reduction, dehydration) reaction will be done on these addition products, in order to obtain a cyclised product.        It is the first time we try these reactions on these kind on molecules, it is why this project needs a lot of optimization and that the yield obtained are medium or equal to zero. However, we observed that the addition reaction with TDAE worked with 4 substrates out of 6. We tried the cyclisation reaction on only one addition product and we think that after some improvement of the reaction conditions and the work-up, we will be able to obtain the product with a good yield. / Tidigare studier har indikerat att molekyler med 1,10-phenanthrolineskelett har en skyddande effekt mot malaria och cancer. Syftet med detta projekt är att syntetisera nya 1,10-phenanthrolinar och cykliska analoger. Framställningsmetoden som användes i denna studie har inte undersökts tidigare.    Föreningen skapades genom en originalmetod utnyttjande en redoxreaktion med hjälp av en TDAE-reagens. TDAE är en elektronrik organisk molekyl och fungerar som en effektiv reduktionsagent. Med hjälp av en enelektronöverföring (SET) kan en anjon framställas under milda förhållanden utifrån halogena derivat. Anjonen tillförs 1,10-phenanthroline-5,6-dione. De olika substraten är heteroaromatiska nitro-benzyliska och quinoniska derivat, samt bromodifluorometylheteroarylerade. Cykliska produkter erhölls genom en tvåstegsreaktion (reduktion, dehydratisering) genomförd i ett enda reaktionskärl.   Med detta projekt har dessa reaktioner för första gången testats på den här typen av molekyler. Det krävs mer optimering eftersom utbytena var låga till medelhöga. Utav sex möjliga substrat fungerade additionsreaktionen med TDAE med fyra stycken. I detta försök testades dock endast en cyklisk reaktion på additionsprodukten. Med ytterligare förbättringar av reaktionsvillkor och upparbetningar förväntas man kunna producera önskad produkt i gott utbyte.

A series of experiments provided data to parameterize and validate a coupled herbicide fate and target plant species effects model. This simulation model is currently designed to predict responses of water hyacinth populations to treatments of the dimethylamine formulation of 2,4- dichloro-phenoxy acetic acid (2,4-D -DMA). Experiments investigated 1) the response of water hyacinth to varying exposures of 2,4-D (DMA); 2) the role of water hyacinth density and herbicide interception in treatment effectiveness using 2,4-D (DMA); and 3) the importance of root exposure to obtain control of water hyacinth using 2,4- D (DMA). Results demonstrated the importance of leaf or canopy interception of 2,4-D (DMA) sprays in obtaining control of water hyacinth populations. The critical threshold plant tissue concentration of 2,4-D (DMA) required to elicit maximum mortality (98%) was estimated to be approximately 12 mg 2,4-D per kg water hyacinth tissue (wet weight). Root uptake apparently plays little or no role in the effectiveness of this herbicide for controlling water hyacinth growth. Validation trials illustrated the efficacy of the current model. The model was validated with data from a field operation. This research has provided considerable insight into optimal use of this auxin-type herbicide for control of water hyacinth, a monocotyledon.

京都大学 / 新制・課程博士 / 博士(工学) / 甲第24601号 / 工博第5107号 / 新制||工||1977(附属図書館) / 京都大学大学院工学研究科都市環境工学専攻 / (主査)教授 伊藤 禎彦, 准教授 西村 文武, 教授 越後 信哉 / 学位規則第4条第1項該当 / Doctor of Philosophy (Engineering) / Kyoto University / DGAM