Dissertations / Theses on the topic 'Ethynyl ketone'

This thesis focuses on the asymmetric reduction of N-protected derivatives of (3S)-3-amino-1-chloro-4-phenyl-2-butanone to their corresponding diastereomeric alcohol products, which are key intermediates in the synthesis of HIV protease inhibitors. Although the stereoselective synthesis of the (S,S) alcohol product is easily achieved, preparing the (R,S) diastereomer is much more challenging. I investigated three diastereoselective reduction processes: 1) Meerwein-Ponndorf-Verley (MPV) reduction, 2) asymmetric transfer hydrogenation, and 3) boron reducing agents. The diastereoselectivity of the MPV reduction still favored the (S,S) product; however, I discovered a significant rate enhancement when the standard catalyst (aluminum isopropoxide) was replaced with aluminum tert-butoxide. Many reaction variables were investigated in the asymmetric transfer hydrogenation reaction and the diastereoselectivity was improved to give a ratio of the desired (R,S) diastereomer to the undesired (S,S) alcohol of 9.5:1. Using chiral oxazaborolidine catalysts, an unprecedented (R,S) to (S,S) ratio of 9.5:1 was achieved. Finally, I investigated the effect of the N-protecting group on the stereoselectivity of the reduction. When the original boc-protecting group was replaced with a phthalimide group, the diastereoselectivity of the MPV reduction was reversed to favor the desired (R,S) product.

In the solid state the rotation of a methyl group is hindered by a potential barrier and at low temperature the rotational motion is characterised by quantum tunnelling. The Pauli Exclusion Principle imposes constraints on the allowable eigenstates of the methyl rotor and leads to a combination of spatial and spin variables. The characteristics of these quantum tunnelling states, labelled A and E, are explored experimentally and methods are investigated for creating prescribed non-equilibrium states. We will investigate and explore the tunnelling polarization associated with the A and E tunnelling-magnetic levels by means of field-cycling NMR. Secondary rf irradiation is used to drive A-E and E-A transitions associated with NMR tunnelling sidebands. This polarization is then transferred to the 1H Zeeman system at a field-dependent level-crossing where the methyl tunnelling frequency equals one or two times the 1H Larmor frequency. The level-crossing contact is a necessary step since the tunnel temperature cannot be measured directly with a pulse. A new pulse sequence is described and the resulting spectra are analogous to the solid effect and dynamic nuclear polarization. Therefore we assign the phrase ‘dynamic tunnelling polarization’ to describe the experiments. Two samples are studied in depth, methyl ethyl ketone and acetophenone which have tunnel frequencies of 495 and 1435 kHz respectively. The experiments investigate the phenomena as a function of a variety of physical parameters in order to determine the fundamental physics.

Diacetyl (2,3-butanedione) is an important flavour active, oxidative compound that has significant impact on cellular health as well as financial impact in industrial fermentations. The presence of diacetyl in certain fermented beverages, such as beer, results in an unpleasant butterscotch-like flavour and its concentration needs to be reduced by yeast to below the taste threshold prior to filtration and packaging. This results in significant process inefficiency. Furthermore, diacetyl negatively impacts cellular health and has been associated with neurodegenerative diseases and general cell aging amongst others. The reduction of this compound is therefore essential for cellular health.
Several yeast cell enzymatic mechanisms responsible for diacetyl reduction were identified and characterised, including Old Yellow Enzyme (OYE) isoforms and D-Arabinose Dehydrogenase (ARA1). OYE isoforms displayed different micromolar affinities and catalytic turnover rates for diacetyl and catalysed diacetyl reduction in a biphasic manner. ARA1 catalysed diacetyl reduction in a monophasic manner with a millimolar Michaelis constant.
Knowledge gained in these studies was applied in investigations of diacetyl production and reduction in industrial brewing operations and the enzymatic systems further exploited for the development of a novel enzyme based assay to determine diacetyl concentrations in beer samples. Concentrations as low as 0.2 muM were detectable with high repeatability.

La production mondiale de solvants représente environ 28 millions de tonnes, dont 5 millions en Europe. L’industrie des peintures et des revêtements en est la principale consommatrice (46 % des solvants produits). Dans ce domaine, les solvants les plus utilisés sont l'acétate d'éthyle, l'acétate de butyle et la méthyl éthyl cétone. Ces molécules sont actuellement synthétisées industriellement à partir de substrats d’origine pétrochimique en présence de catalyseurs homogènes et dans des conditions énergivores. Afin de réduire l’impact environnemental des peintures et revêtements, la substitution de ces solvants issus du pétrole par leurs équivalents bio sourcés a été étudiée dans le cadre du projet européen ECOBIOFOR (FP7/2007-2013/Grant Agreement no 605215), dans lequel se sont inscrits ces travaux de thèse. Ainsi, l’objectif de cette thèse a été de développer, à partir de synthons renouvelables, des procédés de production de ces trois solvants simples à mettre en oeuvre, peu coûteux et respectueux des principes de la chimie verte. Pour la production des acétates d’éthyle et de butyle, deux voies de synthèse ont été étudiées en présence d’une résine échangeuse d'ions comme catalyseur hétérogène. La première voie utilise de l'acide acétique et l’alcool biosourcé correspondant (éthanol ou le butan-1-ol); la seconde met en jeu l’anhydride acétique à la place de l’acide acétique. Dans ces synthèses, quatre résines ont été testées. Des études cinétiques et thermodynamiques ont permis de choisir la résine la plus performante et les conditions de réaction les plus adaptées. Cette étude a finalement permis de proposer un procédé de coproduction des deux acétates efficace et innovant dans lequel la purification des acétates est facilitée, la production de déchets et coproduits est réduite et le recyclage de la résine est possible. L'évaluation des performances des acétates synthétisés dans des formulations de laques nitrocellulosiques et de vernis polyuréthanes a permis de montrer que ces molécules répondent au cahier des charges en terme de séchage, viscosité, formation de film, brillance et adhérence. Enfin, le bénéfice environnemental du processus de coproduction a été mis en évidence par le calcul des métriques de la chimie verte et l'analyse du cycle de vie des esters produits. De plus, l'influence de l'origine des alcools, biosourcés ou pétrochimiques, sur l’impact environnemental a été évaluée. L’impact sur le changement climatique est réduit avec l’utilisation des synthons bio-sourcés. Pour la synthèse de la méthyl éthyl cétone, nous avons décidé d’étudier la réaction de décarboxylation de l’acide lévulinique, molécule plateforme biosourcée disponible et peu coûteuse. Contrairement au principal procédé industriel qui repose sur la déshydrogénation du butan-2-ol d'origine fossile, la méthode développée dans ces travaux utilise des conditions plus respectueuses de l’environnement puisqu’elle est réalisée dans l’eau en présence de persulfate de potassium et d’un sel d'argent à une température raisonnable (100°C). L'évaluation du rôle de chacun des réactifs a permis de proposer un mécanisme réactionnel complexe de cette synthèse. L'étude de l’évolution des espèces en phase solide réalisés par diverses analyses spectroscopiques (RMN du solide, DRX, XPS, AES et MEB) a permis de mettre en évidence les espèces impliquées dans la décarboxylation et finalement de proposer une méthode permettant d’obtenir des conversions et des rendements élevés
Global solvent production accounts for about 28 million tonnes, including 5 million tonnes in Europe. The paint and coating industry is the main consumer (46% of the solvents produced). In this sector, the most used solvents are ethyl acetate, butyl acetate and methyl ethyl ketone. These molecules are currently synthesized industrially from petrochemical substrates in the presence of homogeneous catalysts and under energy-consuming conditions. In order to reduce the environmental impact of paints and coatings, the substitution of these fossil-based solvents by their bio-based equivalents has been studied in the framework of the European project ECOBIOFOR (FP7/2007-2013/Grant Agreement no 605215), in which this thesis work was inscribed. Thus, the objective of this thesis was to develop production processes for these three solvents that would start from renewable synthons and would be simple to implement, inexpensive and respectful of the principles of green chemistry. For the production of ethyl and butyl acetates, two synthetic routes have been studied in the presence of an ion exchange resin as a heterogeneous catalyst. The first route uses acetic acid and the corresponding bio-based alcohol (ethanol or butan-1-ol); the second involves acetic anhydride instead of acetic acid. Kinetic and thermodynamic studies have led to select the most efficient resin and the most suitable reaction conditions. This study has finally allowed to propose an efficient and innovative coproduction process for the two targeted acetates in which their purification is facilitated, the production of waste and co-products is reduced and the recycling of the resin is possible. The evaluation of the performance of the synthesized acetates in nitrocellulose lacquer and polyurethane varnish formulations has shown that these molecules meet the specifications in terms of drying, viscosity, film formation, gloss and adhesion. Finally, the environmental benefit of the co-production process was highlighted by the calculation of green metrics and the life cycle assessment (LCA) of the produced esters. Furthermore, the influence of the origin of alcohols (bio-based or petrochemical) on the environmental impact was evaluated. The impact on climate change is reduced through the use of bio-sourced synthons. For the synthesis of methyl ethyl ketone, we decided to study the decarboxylation reaction of levulinic acid, which is a bio-based platform molecule available and inexpensive. Unlike the main industrial process, which relies on the dehydrogenation of butan-2-ol from fossil origin, the method developed in this work uses conditions that are more respectful of the environment since the reaction is carried out in water in the presence of potassium persulfate and a silver salt at a moderate temperature (100°C). The evaluation of the role of each of the reagents allowed us to propose a complex reaction mechanism for this reaction. The study of the evolution of the solid phase species carried out through various spectroscopic analyzes (SSNMR, XRD, XPS, AES and SEM) made it possible to highlight the species involved in the decarboxylation and finally to propose a method to obtain high conversions and yields

Dissertation (Ph.D.) -- Worcester Polytechnic Institute.
Keywords: Activated carbons; Hydrogen cyanide; Methyl ethyl ketone; Adsorption; Mercury; Monte-Carlo; Solvents; Molecular simulations; Zeolites; Water; Methanol; Nanopores. Includes bibliographical references (leaves 147-150).

The production of packaging goods for cement is one of the most important industries, contributing to income of many workers. Production activities, however, cause air pollution and health risk. The study was conducted to assess air quality and health risks of workers through air quality data and interviewing employees from 2016-2017 at a packaging production factory, Can Tho city, Vietnam. The findings indicated that temperature and noise exceeded the national technical regulations (QCVN 22-26: 2016/TT-BYT) while the humidity, wind speed, light, respirable particles, toxic gases (benzene, toluene, methyl ethyl ketone (MEK)) were in accordance with the national standards for occupational health and safety (Decision 3733/2002/QĐ-BYT). However, health risk assessment showed that long-term exposure in this factory would result in severe impact on health of workers due to indoor air pollution. The non-cancer risk caused by benzene, toluene and MEK for workers in the working sections such as printing, film coating, weaving, spinning and pasting was expected to cause serious impact on workers’ health. The cancer risk (benzene) index was in the range of 1.3 x 10-5 to 7.7 x 10-4 and averaged at 3.3 x 10-4. The study clearly showed that benzene greatly contributes to serious workers’ health effects. Appropriate protection measures such as treatment of air pollutants, regular health check, wearing protective clothes should be implemented to mitigate impact of indoor air pollution at the factory. More importantly, it is necessary to reconsider the standard values of benzene, toluene, methyl ethyl ketone to ensure health of workers.
Công nghiệp sản xuất bao bì xi măng thuộc lĩnh vực ngành xây dựng là một trong những ngành công nghiệp quan trọng, đã góp phần mang lại nguồn thu nhập cho nhiều người lao động. Tuy nhiên hoạt động sản xuất cũng gây ra những vấn đề về ô nhiễm môi trường không khí và rủi ro sức khỏe. Nghiên cứu được thực hiện nhằm đánh giá mức độ ô nhiễm môi trường không khí và đánh giá rủi ro sức khỏe của công nhân thông qua số liệu chất lượng môi trường không khí và phỏng vấn trực tiếp người lao động trong khoảng thời gian từ 2016 - 2017. Kết quả nghiên cứu cho thấy nhiệt độ, tiếng ồn vượt qui chuẩn cho phép (QCVN 22-26:2016/TT-BYT) trong khi độ ẩm, tốc độ gió, ánh sáng, bụi hô hấp, hơi khí độc (Benzen, toluen, methyl ethyl ketone) đạt chuẩn cho phép theo tiêu chuẩn vệ sinh an toàn lao động (QĐ 3733/2002/QĐ-BYT). Tuy nhiên, kết quả đánh giá rủi ro sức khỏe cho thấy công nhân làm việc lâu dài sẽ bị ảnh hưởng nghiêm trọng đến sức khỏe do ô nhiễm không khí. Rủi ro không gây ung thư do benzene, toluene và MEK gây ra đối với công nhân ở từng khu vực có thể gây ảnh hưởng nghiêm trọng đến sức khỏe công nhân làm việc ở các khu vực sản xuất như in, tráng màng, dệt, kéo sợi và dán. Benzene gây rủi ro ung thư với xác suất từ 1 đến 7 người trong 10.000 người trong quá trình làm việc lâu dài tại nhà máy. Nghiên cứu cho thấy benzene đóng góp rất lớn vào khả năng gây ảnh hưởng nghiêm trọng đến sức khỏe công nhân. Môi trường không khí bên trong nhà máy cần được cải thiện hơn nữa đồng thời tuyên truyền nâng cao ý thức công nhân thực hiện nghiêm túc bảo hộ lao động, tổ chức khám sức khỏe định kỳ cho công nhân. Quan trọng hơn là cần điều chỉnh lại các giá trị qui chuẩn để đảm bảo an toàn sức khỏe cho công nhân đang làm việc tại những nơi có sự hiện diện của khí độc như benzene, toluen, methyl ethyl ketone.

La synthèse d'une pophyrine de fer à "anses de panier" chirale comportant des aminoacidés de configuration déterminée est décrite. On a étudié sa pureté optique et sa conformation en solution. Dans une deuxième partie on décrit un nouveau système oxydant catalytique utilisant l'eau oxygénée en présence d'une porphyrine de manganèse et d'imidazole permettant la conversion quantitative d'alcènes en époxydes et d'alcanes en alcools et cétones.

Chapter 1 outlines the potential application of metal alkynyl complexes and then describes the different methods in the literature for the synthesis of alkynyl, poly-ynyl and homo- and hetero-metal complexes. Their chemistry will then be discussed. This Chapter concludes with an outline of the work to be described in the remainder of the thesis. Chapter 2 describes a series of complexes containing a new tricyanovinylethynyl (3,4,4-tricyanobut-3-en-1-ynyl) ligand obtained by direct substitution of a CN group in tetracyanoethene by ethynyl complexes M(C=CH)(PP)Cp' [M = Ru, Os, (PP)Cp' = (PPh₃)₂Cp; M = Ru, PP = dppe, Cp' = Cp, Cp*]. The reactions proceed in higher yield as the metal environment becomes sterically larger and more donating; the normal [2 + 2]-cycloaddition / ring-opened product M{C[=C(CN)₂]CH=C(CN)₂}(PP)Cp' is also formed in some cases. The diynyl Ru(C=CC=CH)(dppe)Cp* reacts with tcne to give only the ring-opened adduct Ru{C=CC[=C(CN)₂]CH=C(CN)₂}(dppe)Cp*. Protonation of Ru{C=CC(CN)=C(CN)₂}(dppe)Cp* (10) afforded the vinylidene. A second transition metal fragment {MLn} [{MLn} = Ru(PPh₃)₂Cp, M'(dppe)Cp* (M' = Ru, Os), RuCl(dppe)₂] can be added to the CN group trans to the first. Compound 10 ready undergoes substitution of the 3-cyano group by nucleophiles. Some unexpected rearrangements and formation of O- and N-heterocyclic compounds were also found. Chapter 3 describes reactions between 1,2 dichlorohexafluorocyclopentene and Ru(C=CH)(dppe)Cp* (1) or Ru(C=CC=CLi)(dppe)Cp* which give Ru(C=C-c-C₅F₆Cl-2)(dppe)Cp* (36) and Ru(C=CC=C-c-C₅F₆Cl-2)(dppe)Cp*, respectively. Ready hydrolysis of 36 to Ru{C=C[c-C₅F₄Cl(O)]}(dppe)Cp* occurs, which can be converted to Ru{C=C(c-C₅F₄Cl[=C(CN)₂])}(dppe)Cp* by treatment with CH₂(CN)₂ / basic alumina. The cyano-fluorocarbon ligand in the latter is one of the most powerfully electron-withdrawing groups known. Chapter 4 describes the three methods of synthesising heterometallic carbon-chain complex {Cp*(dppe)Ru}C=CC=CC=CC{Co₃(μ-dppm)(CO)₇} (40), in two examples showing the first examples of Ru{(C=C)xI}(dppe)Cp* (x = 1, 2) being used in a cross coupling reaction with Ph₃ PAu(C=C)(₃-x)C{Co₃(μ-dppm)(CO)₇}. The reactivity of 40 with PPh₃, MeOTf, tcne, tcnq, Fe₂(CO)₉, NiCp₂ and Co₂(CO)₈ took place on either the C₈ bridge or on either metal centre. Chapter 5 discusses the reaction of 1 with oxalyl chloride which gave {Cp*(dppe)RuC=C}₂CO (52). This complex can be methylated to give [{Cp*(dppe)RuC=C}₂C(OMe)]OTf, which in turn can be protonated to the dication. Knövenagel condensation of 52 with CH₂(CN)₂ gave {Cp*(dppe)RuC=C}₂C{=C(CN)₂}. The reaction of 1 and bis(2,4-dinitrophenyl) oxalate afforded {Cp*(dppe)Ru}{c- C=C[C₆H₃(NO₂)₂]C(O)C(O)O}. The transmetallation reaction of {(Ph₃P)AuC=C}₂CO and RuCl(dppe)Cp unexpectedly gave the cyclic complex [1,4-{Cp(dppe)Ru}₂{c- COC(OMe)=CHCCH}]PF₆. Chapter 6 gives an account of the electrochemistry of many of these redox-active compounds and examines the UV-Vis absorption of the more polarised compounds. Some discussion of the various observed trends is presented. There is also a future direction of this chemistry given at the end of this work.
Thesis (Ph.D.) -- University of Adelaide, School of Chemistry and Physics, 2010

碩士
國立雲林科技大學
環境與安全工程系碩士班
89
In the past forty years in Japan and Taiwan, many thermal explosions have been caused by methyl ethyl ketone peroxide (MEKPO) under the influence of external fire. Thermograms of commercialized MEKPO with dimer were first screened by Differential Scanning Calorimetry (DSC) to determine the heat of decomposition and exothermic onset temperature. Thermal runaway phenomena were then thoroughly investigated by Vent Sizing Package2. (VSP2) Data of thermokinetics and thermal analysis were used for hazard evaluation of MEKPO thermal explosions. Instead of normal one reaction peak from the adiabatic calorimeter, two exothermic peaks on the DSC thermograms is novel finding among literatures. It was found that the reaction order of 1st peak of MEKPO decomposition by isothermal analysis was 1. The Arrhenius parameters were calculated to be Ea (kcalmol-1) = 25.9 and lnA (s-1) = 27, with reproducible confirmation. The reaction order of the 2nd peak of MEKPO decomposition was 0.3 by DSC, showing the Arrhenius parameters of Ea (kcalmol-1) = 28.2 and lnA (s-1) = 24. By VSP2, the Arrhenius parameters were determined as lnA (s-1) = 20.7, Ea (kcalmol-1) = 20.3, and n = 1, respectively. Preventative measures can be established by these basic parameters so that the pro-active disaster prevention program can be practically reached.

碩士
長庚大學
化工與材料工程研究所
94
The objective of this research is to obtain the adsorption equilibrium data of the liquid binary-component solution of MEK and MIBK at room temperature on the granular activated carbon in an agitated adsorption vessel. The goal is to examine the adsorption isotherm of the binary-component system with the single-component adsorption isotherm. Langmuir isotherm can well express both the single component adsorption isotherm of MEK and MIBK on activated carbon. The concentration of MEK and MIBK in the fluid phase discussed in the adsorption in the adsorption isotherm is up to 175 and 90 mmole/l respectively. Fitting with Langmuir isotherm, the parameters od K and q∞ of MEK and MIBK are 0.072 l/mmole, 3.06 mmole/g and 0.122 l/mmole, 7.05 mmole/g respectiviely. The effective diffusion coefficients De of MEK and KIBK in the activated carbon at 30℃ are about 3.7×10-5cm2/s and 6.2×10-5 cm2/s. The concentration of the discussed binary-component solution covers the range from 4 to 25 mmole/l. Extended Langmuir isotherm and Ideal Adsorbed Solution Theory(IAST) models are used to correlate the binary adsorption isotherm with the parameters of the pure component adsorption isotherms. The binary-component adsorption isotherm correlated with Extended Langmuir isotherm has the average error of 95.5% and 39.1% with respective to MEK and MIBK individually. However, the error is reduced to 31.8% and 28.6% for MEK and MIBK respectively if the MEK/MIBK binary-component isotherms are predicted by the IAST-Freundlich isotherms of MEK and MIBK. In the MEK/MIBK system, the binary adsorption isotherms on the activated carbon is better correlated with IAST-Freundlich equation.

碩士
國立高雄應用科技大學
化學工程與材料工程系
99
Methyl Ethyl Ketone (MEK) is a popular solvent/lotion in semiconductor industry, PU leather industry, tape manufacturing industry, and electronic industry. Due to the exhaust of manufacturing process, MEK becomes one of the main sources of the volatile organic compounds. Its harmful to human and surrounding environment cannot be regardless because of its large amount. This study investigates the incineration feasibility of MEK on seven kinds of ferrites (Cu-ferrite, Mn-ferrite, Zn-ferrite, Co-ferrite, Ni-ferrite, Cr-ferrite, Pure-ferrite) synthesized by ferrite process. The results showed that both Cu-ferrite (Cu/Fe=1/2.5) and Cr-ferrite (Cr/Fe=1/2.5) have better catalytic performances. Within the test ranges (variable parameters are inlet concentration of MEK, air flow rate, and oxygen content), the needed reaction temperature could be lower than 300 oC when reach 95 % removal efficiency. The particle size of the catalysts were confirmed around 60-120 nm by SEM inspection. X-ray diffraction results demonstrated that the FP catalysts were the Face-Centered Cubic crystal of spinel structure on fresh catalyst and used catalyst. The crystal did not change after catalytic incineration.

碩士
長庚大學
化工與材料工程研究所
94
This research discuss mainly UV/TiO2 process in the continuous packed bed reactor. We use glass pearls for loading TiO2.The gaseous phase pollutant is Methyl Ethyl Ketone (MEK) .The changes of this experiment includes such effects as wavelength of UV light , initial concentration, system temperature, flow rate and retention time, etc. Then we combine Langmuir-Hinshelwood adsorption theory with Fick mass transfer theory for examining the kinetic equation suitable for this experimental system. Find out several parameter such as L-H reaction rate constant (k) , MEK adsorption constant (Ka) , activate energy(E) , frequency factor (k0).At the end of our experiment we combine photocatalytic process with ozone process, and observe the effect of synergy reaction. From the experimental result we can conclude several points. Use UV light of wavelength 254nm to decompose MEK is better than UV light of wavelength 365nm.When we raise MEK initial concentration, it will induce to decrease the MEK conversion ratio and make photocatalyst more easily deactivate. The retention time effects for MEK photolysis can divide into two stages. When retention time is smaller than 30 seconds, the getting rise of retention time is in direct proportion to MEK conversion ratio. When retention time is greater than 30 seconds, the getting rise of retention time have nothing to do with MEK conversion ratio. The aspect of kinetic parameters, we can find k value will increase as temperature improves. It represents that reaction rate speeds up. Ka value will be reduced as temperature increases. It represents an unfavorable effect for the reactant to adsorb. As to three process of TiO2/UV, O3/TiO2, O3/TiO2/UV, under the same condition of retention time, decomposing efficiency of MEK is O3/TiO2/UV> TiO2/UV> O3/TiO2. Under the conditions of high initial concentrations and low retention times, the treatment result of O3/TiO2/UV process is the best.

博士
雲林科技大學
工程科技研究所博士班
96
The thermal stability of solutions of methyl ethyl ketone peroxide (MEKPO) dissolved in dimethyl phthalate (DMP), with the presence of inorganic acids (HCl, HNO3, H3PO4, and H2SO4) and the other incompatible materials as contaminants had been studied. MEKPO is extensively employed in the chemical industries. Several severe fires and explosions have been induced by MEKPO in East Asia during the last four decades. Therefore, this study was conducted with a view to realize its essentially hazardous characteristics. In this study, we used differential scanning calorimetry (DSC), thermal activity monitor III (TAMIII), and vent sizing package 2 (VSP2) with the following kinetics evaluation to identify the root-cause of the runaway reactions and kinetics-based curve fitting to assess hazardous phenomena via utilized curve fitting to optimize the kinetic parameters. Inorganic acids and other contaminants were mixed with MEKPO and studied under various perturbed situations. All the results indicated that when MEKPO is mixed with contaminants, it dramatically increases the degree of hazard in the initial stage, especially affected by HNO3. To lessen the degree of hazard, hazardous information must be provided to the manufacturing process.

碩士
國立雲林科技大學
環境與安全工程系碩士班
93
Historically, methyl ethyl ketone peroxide (MEKPO), a universal hardener in the rubber industries, has caused many serious explosions and fires in Taiwan, Japan, Korea, and China. This study used certain thermal analytical methods to thoroughly explore both why MEKPO led to these accidents and what happened during the upset conditions. Potential process contaminants (inorganic acids), such as HNO3、H3PO4、HCl、H2SO4, were deliberately selected to mix with MEKPO for discussing the exothermic phenomenon. Differential scanning calorimetry (DSC) and Vent Sizing Package 2 (VSP2) were employed to evaluate the runaway reaction. The results indicate that MEKPO is highly hazardous when mixed with any of the above-mentioned contaminants. Fire and explosion hazards could be effectively lessened if the safety information are properly imbedded into manufacturing processes.

碩士
國立雲林科技大學
環境與安全工程系碩士班
91
In the past four decades in Japan, Taiwan and China, Methyl Ethyl Ketone Peroxide (MEKPO) has caused many thermal explosions hazard with its thermal instability and incompatibility. In this study, the thermal decomposition and runaway behaviors of MEKPO with about 1 wt % incompatibilities such as H2SO4, HCl, NaOH, KOH, Fe2O3, FeCl3, and FeSO4 were analyzed by DSC (Differential Scanning Calorimetry) thermal analysis and VSP2 (Vent Sizing Package2) adiabatic calorimetry. The thermokinetic data, such as onset temperature, heat of decomposition, adiabatic temperature rise, and self-heat rate, were obtained by the abovementioned calorimeters. From the thermograms of pure MEKPO and these ones with incompatible substances, all the onset temperatures were advanced, especially with alkaline or iron ion material. In some tests, the incompatible reactions under low temperature conditions were found. In order to confirm the incompatible reaction hazard phenomena, we thoroughly investigated MEKPO with different incompatibilities by VSP2. From VSP2 tests, various onset temperatures, heat of decompositions, adiabatic temperature rises, and self-heat rates could be clearly compared. From the simple calculated kinetics, all the activation energies of incompatible tests were, in turn, corroborated to be lower than the MEKPO alone in a deeper degree.

Doctor of Philosophy
Department of Chemical Engineering
Keith L. Hohn
The present work describes the conversion of bio-derived methyl ethyl ketone (MEK) into different useful chemicals. The first part discusses the direct conversion of MEK to butene over supported copper catalysts (Cu-Al₂O₃, Cu-zeolite Y sodium (Cu-ZYNa) and Cu-zeolite Y hydrogen (Cu-ZYH)) in a fixed bed reactor. In this reaction, MEK is hydrogenated to 2-butanol over metal sites, and further dehydrated on acid sites to produce butene. Experimental results showed that the selectivity of butene was the highest over Cu-ZYNa, and it was improved by finding the optimum reaction temperature, hydrogen pressure and the percentage of copper loaded on ZYNa. The highest selectivity of butene (97.9%) was obtained at 270 °C and 20 wt% Cu-ZYNa. Over Cu-Al₂O₃, the selectivity of butenes was less than Cu-ZYNa since subsequent hydrogenation of butene occurred to produce butane. It was also observed that with increasing H₂/MEK molar ratio, butane selectivity increased. However, when this ratio was decreased, hydrogenation of butene was reduced, but dimerization to C₈ alkenes and alkane began to be favored. The main products over 20% Cu-Al₂O₃ were butene and butane, and the maximum selectivity of butene (87%) was achieved at an H₂/MEK molar ratio of five. The lowest selectivity of butene was obtained using Cu-ZYH, reaching ~40%. It was found that the amount of acidity in Cu-ZYH is much higher than in Cu-ZYNa (from (NH₃-TPD) measurements). This could have caused the selectivity of butene to decrease as a result of dimerization, oligomerization and cracking reactions. The second part describes the conversion of MEK to higher ketones in one step using a multifunctional catalyst having both aldol condensation (aldolization and dehydration) and hydrogenation properties. 15% Cu supported zirconia (ZrO₂) was investigated in the catalytic gas phase reaction of MEK in a fixed bed reactor. The results showed that the main product was 5-methyl-3-heptanone in addition to 5-methyl-3-heptanol and 2-butanol with side products including other heavy products (C₁₂ and up). The effects of temperature and the molar ratio of reactants (H₂/MEK) on overall product selectivity were studied. It was found that with increasing temperature, the selectivity to C₈ ketone increased, while selectivity to 2-butanol decreased. The hydrogen pressure plays significant role on the selectivity of products. It was observed that with increasing the H₂/MEK molar ratio, 2-butanol selectivity increased due to hydrogenation reaction while decreasing this ratio leads to increasing aldol condensation products. In addition, it was noted that both conversion and selectivity to the main product increased using a low loading percentage of copper, 1% Cu-ZrO₂. The highest selectivity of 5-methyl-3-heptanone (~63%) was obtained at temperatures around 180 °C and a molar ratio of H₂/MEK of 2. Other metals (Ni, Pd and Pt) supported on ZrO₂ also produced 5-methyl 3-heptanone as the main product with slight differences in selectivity, suggesting that a hydrogenation catalyst is important for making the C₈ ketone, but the exact identity of the metal is less important. The third part discusses the conversion of C₈ ketones to C₈ alkenes and C₈ alkane over a catalyst consisting of a transition metal (Cu or Pt) loaded on alumina (Al₂O₃). These bifunctional catalysts provide both hydrogenation and dehydration functionalities. The main products over 20% Cu-Al₂O₃ were a mixture of 5-methyl-3-heptene, 5-methyl-2-heptene and 3-methyl heptane. However, using 1% Pt-Al₂O₃ the major product was 3-methyl heptane with a selectivity reaching over 97% and a conversion of 99.9 %. Both temperature and the hydrogen pressure play an important role on the conversion of C₈ ketone as well as the selectivity of products (C₈ alkenes and C₈ alkane). Over 20% Cu-Al₂O₃, it was observed that increasing the reaction temperature led to an increase in the selectivity to C₈ alkane as a result of hydrogenation of the C₈ alkene. Also, it was observed that with an increase in H₂/C₈ ketone molar ratio, C₈ alkane selectivity increased. However, when this ratio was decreased, the further hydrogenation of C₈ alkene to C₈ alkane was reduced. The highest selectivity of C₈ alkene (81.7%) was obtained at 220 °C and a H₂/C₈ ketone molar ratio of 2. In addition, an experiment was carried out using a low loading percentage of copper, and it was noted that both conversion and selectivity to the main products decreased over 1% Cu-Al₂O₃. Over 1% Pt-Al₂O₃, C₈ alkane was the major product with different temperatures indicating that further hydrogenation of C₈ alkene was promoted on 1% Pt-Al₂O₃. At low temperature, for both Cu-Al₂O₃ and Pt-Al₂O₃, significant amounts of C₈ alcohols are formed because subsequent reactions do not proceed at a fast enough rate. Also using 1% Pt-Al₂O₃, the main product selectivity is still C₈ alkane with all H₂/C₈ ketone ratios.

博士
國立中興大學
化學工程學系所
96
Methyl ethyl ketone peroxide (MEKPO) is extensively employed in the chemical industries. In the past four decades, several thermal explosions hazard with its thermal instability and incompatibility caused fires and explosions have been induced by MEKPO in East Asia. In this study, the thermal decomposition and runaway behaviors of MEKPO with about 1 mass % incompatibilities such as H2SO4, HCl, NaOH, KOH, Fe2O3, FeCl3, and FeSO4 were analyzed by differential scanning calorimetry (DSC) with the following kinetics evaluation to identify the root-cause of the runaway reactions and kinetics-based curve fitting to assess hazardous phenomena via utilized curve fitting to optimize the kinetic parameters. And used Vent Sizing Package2 (VSP2), the adiabatic calorimetry to obtain the thermokinetic data and analyzed the hazardous phenomena. From the thermal curves of pure MEKPO and ones with incompatible substances, all the onset temperatures were advanced, especially with alkaline or iron ion material. In some tests, the incompatible reactions under low temperature conditions were found. To confirm the incompatible reaction hazard phenomena, we thoroughly investigated MEKPO with different incompatibilities by VSP2. From the tests, various onset temperatures, heat of decompositions, adiabatic temperature rises, and self-heat rates could be clearly compared. From the simple calculated kinetics, all the activation energies of incompatible tests were corroborated to be lower than the MEKPO alone in a deeper degree.

碩士
國立雲林科技大學
環境與安全衛生工程系
103
Abstract The study is based on a chemical plant in Kaohsiung Linyuan Industrial Area. We used ALOHA (Area Location of Hazardous Atmosphere) analysis and simulation software, according to the geographical location and environmental characteristics. To predict the harmful gas diffusion distribution, after the toluene, methyl ethyl ketone, cyclohexanone, etc.tanks leakage caused by the earthquake. The diffusion results (Figure footprint footprint) nested a Google Earth map, discussed the following items, as a reference to take appropriate control measures and emergency response it to be in advance of disasters can grasp the situation, to reduce disaster risks. . 1. The diffusion hazards analysis of chemical substance in the tank leakage. 2. Effect of changes in wind direction diffusion range of hazards 3. Impact on the degree of diffusion of harmful range difference variation depending on the wind speed. 4. Flammable gas leaks, vapor cloud explosion hazard scope of the analysis. 5.Compare the diffusion hazards difference between methyl ethyl ketone, cyclohexane, toluene, etc. Forecasting heavy gas cloud chemical diffusion distribution of simulation results are summarized as follows: 1. The simulation results show that the diffusion hazards range order, is: cyclohexanone> toluene> butanone. 2. The greater the amount of leakage per unit time, the greater the range of diffusion harm. 3. The lower the wind speed, the greater the harm diffusion range. KeyWords：ALOHA、toluene、 methyl ethyl ketone、 cyclohexanone

碩士
國立臺灣科技大學
化學工程系
107
The tech industry becomes the major industry in Taiwan gradually due to the increase in the demand of computer, communication, and consumer electronics. The amount of organic solvent used for manufacture thus is increased sharply. Some companies assign waste treatment companies to incinerate these waste solvent, resulting in plenty of air pollution and energy consumption. The chemical looping combustion (CLC) is a novel combustion process with flameless, high combustion efficiency, and direct separation of carbon dioxide. The operation conditions, such as reactor design, degree of fluidization, and contact time between gas and solid, will affect the reaction rate. The oxygen carrier plays the important role in CLC, and the natural iron ore is widely used due to its environmentally friendliness and cheap cost. In this study, the Brazilian iron ore was used as the oxygen carrier, and the waste solvent of methyl ethyl ketone was used as the fuel. The experiment was carried out in interconnected fluidized bed. In this system, the air reactor and the fuel reactor were fast fluidized bed and bubbling bed, respectively. The oxygen carrier was transferred between the fuel reactor and the air reactor, which provided oxygen in the fuel reactor and regained oxygen in the air reactor. The temperature, the pressure distribution and the composition of the exhaust gas (air reactor and fuel reactor) in the system were continuously monitored. Three parts of operating conditions were investigated in this work. In the first part, the effect of gas flow rate of air reactor and loop seal on fluidization phenomenon was analyzed to establish the basic operation parameters. The second part was the system temperature, which affected the carbon conversion and purity of CO2. In the last part, the maximum treatment capacity for waste solvent of this system was evaluated. The experimental results indicated that the optimal parameters were obtained at 7.5 L/min of air flow for air reactor, 4 L/min of N2 for loop seal, 750oC of the system. The maximum feed rate of solvent was 2 mL/min in this system. The composition of the flue gas was 83% carbon dioxide, 10% methane, 6% ethylene, 1% carbon monoxide. The research results can be used as a reference for the operation parameters of pilot.

碩士
中國醫藥大學
環境醫學研究所碩士班
97
Noise has been documented as the most important hazard about hearing loss, especially at occupational settings. Aircraft maintenance workers are at the high risk of hearing loss associated with a great amount of noise exposure at work such as regular check of airplane taking off and landing. Organic solvents exposure has been noted as an additional factor of hearing loss among aircraft maintenance workers. Previous studies have revealed that organic solvents related occupational hearing loss might be due to the ototoxicity after exposure in workers. N-hexane and MEK are the most frequently used solvents during the aircraft maintenance process. To the best of our knowledge, limited studies have been conducted on the hearing loss associated with n-hexane and/or MEK exposure and the interaction of with noise among aircraft maintenance workers. The purpose of this study is to investigate whether among aircraft maintenance workers exposed to noise, n-hexane, and MEK are at elevated risk of hearing loss. The aircraft maintenance workers in Taiwan were recruited as the subjects of this study. We classified these subjects into seven exposure groups based on their exposure profiles of noise, n-hexane, and MEK, including noise exposure only (group 1), n-hexane exposure group (group 2), MEK exposure only (group 3), noise and n-hexane co-exposure (group 4), noise and MEK co-exposure (group 5), noise, n-hexane, and MEK co-exposure (group 6), and non-exposure (group 7). Hearing loss examination was used to estimate the status of hearing impairment among workers. Information on demographics and potential confounders were collected using questionnaires. Linear regression models were used to estimate the risk of hearing loss among exposure groups controlling for potential confounders. The results showed that the ranges of hearing threshold loss of the all exposure groups on left and right ears were 3.1~9.0、3.8~11.8、2.8~8.8、2.7~8.4、3.6~14、2.7~9.6 dB, respectively; The prevalence of hearing loss among the corresponding exposure groups were 33.3%、35.1%、21.7%、32%、33.3%、34.5%, respectively. After adjustment of confounders, the threshold of hearing loss significantly increased as the exposure level increased. The results of this study indicate that exposure to occupational noise and organic solvents increased the risk of hearing loss for the aircraft maintenance workers. The aircraft maintenance workers are encouraged to use personal protective equipments at the work. We suggest that hearing conservation programs should be implemented for these aircraft maintenance workers.

碩士
義守大學
化學工程學系暨生物技術與化學工程研究所
107
Butanone (MEK) and 3-methyl-2-butanone (MIPK) are volatile organic compounds (VOCs), and often used in factories as solvents, dewaxing agents and cleaning agents, which will lead to water and air pollution. Ozone can effectively decompose organic compounds due to its highly oxidizing properties. This research was applied the high oxidation capacity of ozone to study the products of reaction of ozone with methyl ethyl ketone and 3-methyl-2-butanone. The results will helpful for understanding the oxidation mechanism of oxidation reaction by ozone. This study was applied GC/MS and IR to analyze and identify the products of reaction of methyl ethyl ketone and 3-methyl-2-butanone with ozone. The products of the ozone reaction with MEK include acetaldehyde, acetic acid, 3-hydroxy-2-butanone and butanedione. After the reaction of ozone with MIPK, the products detected were acetaldehyde, acetone, 3,3-dimethyl-2-butanone, vinyl acetate, 3-hydroxy-3-methyl-2-butanone and 2-methyl-3-pentanone. When ozone reacts with ketones, ozone will react with the position of α-CH. MEK has secondary and primary α-CH, while MIPK has tertiary and primary α-CH. The results show that ozone does not react with the position of primary α-CH, and tertiary α-CH is easier to react with ozone than secondary α-CH. The reaction mechanism is also discussed.

碩士
國立成功大學
環境醫學研究所
92
The exposure of the humans to the chemical mixtures is the general rule in the general environment as well as in most occupational settings. Lower toxicity or higher toxicity from mixtures than the expected depends on their constituents and potencies. It is very likely that the workers could be exposed to N,N-dimethylformamide (DMF), methyl ethyl ketone (MEK), and toluene (TOL) in the occupational environments simultaneously. This study was aimed to investigate the effects of the different co-exposure levels of MEK and toluene and different DMF on different biomarkers of DMF exposure metabolism-free form (U-DMF) and biotransformation-required forms (U-NMF, and U-AMCC), and the effects of co-exposure to DMF on urinary MEK biomarker, respectively. Twenty workers were selected from a two-stage field investigation strategy and were classified into four subgroups based on their DMF exposure and co-exposure levels. Breathing-zone air concentrations of DMF, MEK and TOL as well as dermal DMF exposure were determined for two consecutive and another five consecutive working days. The concentrations of U-DMF, U-NMF, U-AMCC and U-MEK in pre- and post-shift as well as during at least 36-hour period since the end of the exposure for each individual were analyzed. For post-shift urine measurements, we found U-DMF concentrations in high DMF subgroups were significantly higher than those in low DMF subgroups (p＜0.05). On the other hand, U-NMF and U-AMCC concentrations in high-DMF-high-coexposure subgroup were significantly lower than those in high-DMF-high-coexposure subgroup but no significant differences between two low DMF subgroups. Metabolic index (MI) showed the biotransformation from DMF to NMF, but not from NMF to AMCC, was significantly suppressed at high co-exposure (p＜0.001). We also found a significant daily accumulation of pre-shift U-NMF across five consecutive working days for those who have high co-exposure to high MEK/TOL and the day-to-day increase of U-NMF at pre-shift was approximate 1.4-fold given the occupational exposure to DMF at the same level. The lag time of excretory U-NMF for high MEK/TOL co-exposure group was significantly longer that for low co-exposure group in conventional kinetics study. The estimates of half-life, area under curve (AUC), and mean residence time (MRT) also showed the same tendency as found for lag time. For the biological monitoring of MEK part, the regression equations of A-MEK to post-shift U-MEK showed no significant differences between high and low DMF co-exposure groups. On the other hand, the estimates of the half-life and maximum concentration of post-shift U-MEK for high DMF co-exposure groups were greater than those for low DMF co-exposure groups in kinetics study. Owing to the insufficient sample sizes, this finding warranted a further study. The discrepancy between conventional kinetics approach and physiologically-based pharmacokinetics (PBPK) approach could result from the differences in races and exposure scenarios as well as insufficient sample size. We concluded that co-exposure to high MEK/TOL could result in 1. the suppression of U-NMF and U-AMCC at high DMF exposure; 2. the accumulation of U-NMF at daily pre-shift urines; 3). the increases of the lag time, half-life, MRT, and AUC for U-NMF. Difference. For the biological monitoring of MEK part, no significant effects of co-exposure to DMF on post-shift U-MEK. Some effects might exist in the estimates of the kinetic parameters and this warranted a further study to confirm. Due to the ubiquity of co-existence of MEK, TOL and DMF in occupational settings, biological monitoring for the above-mentioned chemicals should be carefully evaluated while the co-exposure is substantial and a more comprehensive longitudinal health evaluation program should be performed for those workers.

博士
長庚大學
化工與材料工程研究所
95
This study attempts to combine the technologies of adsorption of volatile organic compound (VOC) on activated carbon and oxidation of VOC by O3. In the adsorption/oxidation process, the effects of ozone for the adsorption characteristics of methyl ethyl ketone (MEK) vapor on activated carbon are investigated. The kinetic parameters of reaction for MEK vapor and O3 on activated carbon are also determined. The results show that the destructive efficiencies of MEK by 1000 ppmv O3 on activated carbon are from 12.4 % to 48.5 %. From the power law kinetic model, the apparent kinetic constant, k, is obtained having a value of 0.0438 h-1 in this process. Moreover, the activation energy, Ea, is found to be 5.12 Kcal/mole and the value of rate constant, A, is 189.54 h from the analytical results of the Arrhenius equation. The Langmuir-Hishelwood model (Escobar et al., 2004) is also used to determined the kinetics parameters of and . The values are found to be 0.035 and 0.6183, respectively. Finally, the modified Wheeler equation (Wood and Moyer, 1989; Yoon and Nelson, 1984; Busmundrud, 1993) in combination with the power law kinetic model or Langmuir-Hishelwood is used to predict the breakthrough curves. The destruction of MEK can be effectively promoted as the bed height of activate carbon and the concentration of ozone increase. The pretreatment of the metal-organic chemical vapor deposition process is used to modify the characteristics of the activated carbon The pore and surface characteristics of various adsorbents are analyzed by BET, ICP/AES, and SEM/EDX. In addition to this, desorption experiments are performed in a thermogravimetric analyzer. The kinetics parameters, E, A, and n, of thermal desorption from spent adsorbents saturated with MEK vapor are also calculated. The kinetic parameters, E, A, and n, of thermal desorption from the spent adsorbents saturated with MEK vapor are calculated according to the differential method. The optimum fitting results are where n=1.5. The differential method has a better fitting curve and all the fitting R-square values are more effective than 0.88. The apparent activation energy of AC with 1000 ppmv O3 for MEK vapor are 22.67 – 18.32 kJ/mole (303–363 K)and the apparent activation energy of Cu/AC with 1000 ppmv O3 for MEK vapor is 29.32- 10.64 kJ/mole(303 -363K). The destructive efficiency of MEK is still greater than 95% even after a prolonged operational time when ozone concentration is increased to 7800 ppmv and the amount of activated carbon is increased to 5 g. From the results of this study, adsorption process in combination with ozone oxidation shows potential for the control of VOCs and odor.

碩士
中國醫藥大學
職業安全與衛生學系碩士班
99
Objectives: The repeated-measure study was to investigate effects of co-exposure to occupational noise and methyl ethyl ketone (MEK) on ambulatory blood pressure among aviation industry workers. Methods: We selected an aircraft manufacturing company to recruit 145 volunteers as the study population. These workers were classified into five different-exposure groups based on their individual noise levels and MEK concentrations at work, including the co-exposure (≥71.2 dBA; MEK ≥1.182 ppm), noise-exposure (≥71.2 dBA; MEK <1.182 ppm), MEK-exposure (<71.2 dBA; MEK ≥ 1.182 ppm), low-exposure (<71.2 dBA; MEK <1.182 ppm) and control groups. The ambulatory blood pressure monitoring device and noise dosimeter as well as low-flow air sampling pump with charcoal tubes and GC/FID were used to determine individual 24-hour ambulatory blood pressure, 24-hour noise exposure and 8-hour occupational exposure to MEK. We collected confounders from personal health check-ups, self-administered questionnaire and activity records. The linear mixed effects regression models were used to investigate effects of co-exposure to noise and MEK exposure on ambulatory systolic blood pressure (SBP) and diastolic pressure (DBP) during day time (7:30-16:30), night time (16:30-23:00), sleep time (23:00-7:30) and 24-hour average on working and non-working days among all subjects. Results: We found that the co-exposure group had significantly higher mean values of ambulatory SBP than the control group during the work time (13.75 mmHg, 95% CI = 5.04-22.45), off-duty time (8.96 mmHg, 95% CI = 0.15-17.78), sleep time (11.05 mmHg, 95% CI = 2.19-19.92) and 24-hour average (11.16 mmHg, 95% CI = 3.43-18.89) on the working day. The MEK-exposure group also had significantly higher mean values of ambulatory SBP then the control group during the work time (12.31 mmHg, 95% CI = 3.49-21.13) and 24-hour average (9.52 mmHg, 95% CI = 1.64-17.40) on the working day. Per 1-dBA increase in the 24-hour average noise exposure was significantly associated with transient elevations of SBP (0.26 mmHg, 95% CI = 0.15-0.36; 0.13 mmHg, 95% CI = 0.04-0.22) and DBP (0.24 mmHg, 95% CI = 0.16-0.31; 0.10 mmHg, 95% CI = 0.03-0.16) among the co-exposure group on both working and non-working days. Such effects on SBP and DBP still persisted at the 120-min time-lagged noise exposure. Conclusions: Co-exposure to noise and MEK may affect the ambulatory blood pressure among aircraft manugacturing workers. MEK exposure may have an obviously higher effect than noise exposure. Co-exposure to noise and MEK may have a synergistic effect on ambulatory SBP.

碩士
國立臺灣大學
化學研究所
90
Abstract In this thesie, I describe the reductive double electrophilic coupling reactions of ethyl thiophene-2-carboxylate and ketones promoted by SmI2/HMPA and application of these compounds in the areas of liquid crystals and photochromism are under study. Ethyl thiophene-2-carboxylate underwent the reductive double electrophilic coupling reactions with aryl ketones by promotion of SmI2/HMPA to give disubstituted 4,5-dihydrothiophene-2-carboxylates in high regio- and stereoselective manner. The products obtained from the reductive double electrophilic reactions of ethyl thiophene-2-carboxylate were converted to thiophene-fused p-terphenyls, polybenz[b]thiophenes and thiophene-fused polycyclic compounds via sequential oxidation-electrocyclization-oxidation reactions. The SmI2-promoted coupling reactions of ethyl thiophene- 2-carboxylate with aryl ketones, followed by acid-catalyzed dehydration and oxidative aromatization gave dialkenylthiophenes M which under went electrocyclizations upon irradiation to give the corresponding closed-ring species N constitutes a novel photochromic system. By a simplar procedure, dienes 37, trienes 38 and benzothiophenes 39 bearing long-chain substitutents were prepared. Among them, dienes 37 and trienes 38 possess the liquid crystalline properties of smectic-A type. Thieno-p-terphyls 39 exist as solids with rather high melting points, even though they are equipped with soft long chains of decoxy, dedecoxy, tetradecoxy and hexadecoxy groups. By comparison with the thienyl rings in 37 and 38, the rigid core of benzothiophene is longer to disfavor the liquid-crystalline property.

Humans are exposed to electrophilically reactive compounds, both formed endogenously and from exogenous exposure. Such compounds could react and form stable reaction products, adducts, at nucleophilic sites in proteins and DNA. The formation of adducts constitutes a risk for effects, such as cancer and contact allergy, and plays a role in ageing processes. Adducts to proteins offer a possibility to measure electrophilic compounds in vivo. Adductomic approaches aim to study the totality of adducts, to specific biomolecules, by mass spectrometric screening. This thesis describes the development and application of an adductomic approach for the screening of unknown adducts to N-terminal valine (Val) in hemoglobin (Hb) by liquid chromatography tandem mass spectrometry (LC/MS/MS). The adductomic approach is based on the FIRE procedure, a modified Edman procedure for the analysis of adducts to N-terminal Val in Hb by LC/MS/MS. The adduct screening was performed by stepwise scanning of precursor ions in small mass increments and monitoring four fragments common for derivatives of detached Val adducts, in the multiple reaction monitoring mode. Samples from 12 smokers/nonsmokers were screened with the adductomic approach, and seven previously identified adducts and 19 unknown adducts were detected. A semiquantitative approach was applied for approximate quantification of adduct levels. A strategy for identifying unknown Hb adducts using adductome LC/MS/MS data was formulated and applied for the identification of unknown adducts. Identifications were based on the observed m/z of precursor ions and retention times combined with databases and Log P calculations. Hypothesized adducts were generated in vitro for comparison and matching with the corresponding unknown adducts. Five identified adducts correspond to the precursor electrophiles ethyl vinyl ketone (EVK), glyoxal, methylglyoxal, acrylic acid, and 1-octen-3-one. These adducts, except the adducts corresponding to glyoxal and methylglyoxal, have not been observed as protein adducts before.  Probable exposure sources to these electrophiles are diet and/or endogenous formation. The observation of these adducts motivate further studies to evaluate possible contributions to health risks, as well as their potential as biomarkers of exposure. The adduct from EVK was quantitatively assessed through different experiments to estimate the daily internal dose (area under the concentration-time-curve, AUC). EVK is about 2 × 103 more reactive than the reference compound acrylamide. The EVK adduct was shown to be unstable, with a relatively short half-life. The daily AUC in humans of EVK was estimated to be about 20 times lower than the corresponding AUC of acrylamide from intake via food. To confirm the observation of the detected unknown adducts and obtain a statistical foundation, analysis of unknown adducts were performed in large sets of blood samples (n = 50–120) from human cohorts. The majority of the previously detected unknown adducts were found in all analyzed samples, and the levels of many adducts showed large variations between individuals. The cause and significance of these observed variations are not yet clarified, but are of importance for the directions of future studies. In conclusion, a new approach for identification of unknown human exposure to electrophiles was developed and successfully applied.

At the time of the doctoral defense, the following paper was unpublished and had a status as follows: Paper 4: Submitted.