The catalysis reaction performance, such as yield, is very crucial in organic chemistry. And predicting the reaction yield is still very challenging. In this thesis, machine learning is used to predict the reaction yield in a C–N cross-coupling approach. The reaction data are from the high-throughput experimental data with four variables: reactants, Pd catalysts, additives, and bases. Each reaction data will give the corresponding yield. The data are from the literature, which has been uploaded. The total data number used in machine learning is 7910. The method mainly consists of four steps. First, load the csv data and import modules. Second, encode data with molecular fingerprint or one-hot encoding. The data will be normalized if there is need. Third, split the dataset into train and test set with the size ratio of 7/3 or 8/2. Fourth, use six machine learning models to learn the data and evaluate their performance. Then, compare the prediction yield of the test set. The accuracy in prediction (RMSE value and R-squared) and running time will be considered for evaluation. By comparing the RMSE and R-squared values of different models, we can decide which one has better performance and better fitting results. Improved reaction performance, or high-performance catalysts and their characteristics may be obtained.

In a forensic investigation involving oil, a comparative analysis named oil spill fingerprinting between a source and an oil spill is normally performed. It is based on detecting a certain selection of biomarkers with gas chromatography (GC) coupled to mass spectrometry (MS) which are later divided into diagnostic ratios (DRs). An international guideline formed by European Committee for Standardization (CEN) denoted CEN/TR 15522-2:2012 describes the process of conducting oil spill fingerprinting. This method is currently being inspected and adjusted for standardization into EN 15522-2:2022. One section of the upcoming standard describes sample clean-up which is important to inhibit possible matrix effect that could either enhance or reduce peak intensity in the chromatogram. There is yet no conclusive SPE (Solid Phase Extraction) protocol in the current draft version of EN 15522-2:2022. The aim with this study was to develop such a protocol. Development included comparative testing of the recommended stationary phases silica and Florisil®. Additionally, the effect of both elution solvent and elution volume were investigated. The protocol must pass validation criteria to be implemented at National Forensic Centre (NFC) and possibly be used in the final version of EN 15522-2:2022. A successful method for Heavy Fuel Oil (HFO), diesel and lubricating oil was achieved with activated Florisil® as stationary phase, eluted with 6 ml dichloromethane (DCM). If the evidence material is suspected to contain FAMEs (Fatty Acid Methyl Esters), then 2 % acetone should be added to the DCM. The final SPE column was packed with 0.5 glass wool, 4 cm Florisil® and 0.5 cm sodium sulfate. Based on successful validation result, the SPE protocol should be considered for the final version of EN 15522-2:2022 as well as for implementation at NFC.

Untreated human sewage pollution in surface water is of concern because it contributes to the degradation of aquatic ecosystems and it could be a potential hazard to human health. Also, any pollution of surface water, which ultimately supplies drinking water, may affect the drinking water quality. Improper operation and maintenance of separate storm sewer systems are prominent contributors of untreated sewage to source waters, resulting from illicit connections, leakage of sewers, or cross-connections. This thesis studied anthropogenic markers to track untreated sewage in an urban watershed with separate storm sewer system, under dry weather conditions. The main feature of these chemical markers is their degradation behavior at municipal wastewater treatment plants: some markers are completely removed (labile markers), whereas others show only partial or no removal at all (conservative markers). A set of ubiquitous chemical markers with practical analytical detection limits was selected to exploit the labile vs conservative distinction, and determine if untreated human sewage was discharged from stormwater outfalls. The presence of labile markers alone was not enough to confirm the occurrence of untreated sewage in stormwater outfalls. The concentration ratios between labile and conservative markers from several chemical groups (pharmaceuticals and personal care products, over-the-counter medications, artificial sweeteners, and human metabolites) created a chemical fingerprint of untreated sewage, and it was statistically demonstrated to track untreated human sewage in local stormwater outfalls. / Civil Engineering

Les moisissures sont des biocontaminants courants des environnements intérieurs causant la biodégradation des matériaux qu'ils colonisent et favorisant l'apparition de diverses pathologies, notamment respiratoires telles que des allergies, des infections ou des toxi-infections.En raison de ces impacts, la maîtrise de la contamination fongique constitue une préoccupation majeure pour des secteurs aussi divers que les industries agro-alimentaires, pharmaceutiques, les hôpitaux ou encore les établissements patrimoniaux. Actuellement, les techniques utilisées pour surveiller ces environnements sensibles reposent sur la mesure de particules biologiques en suspension dans l'air émises après sporulation des moisissures. Afin de prévenir les effets de la prolifération de moisissures, le Centre Scientifique et Technique du Bâtiment (CSTB) a développé un indice de contamination fongique basé sur la détection de Composés Organiques Volatils (COV) spécifiques émis dès le début de cette croissance microbienne avant même l'émission dans l'air de particules délétères (Moularat, Robine et al. 2008; Moularat, Robine et al. 2008). Cet outil, breveté en 2007 (Moularat 2007), a été employé lors de différentes campagnes de mesures dans l'habitat, les bureaux, les écoles, les crèches, les musées…(Moularat, Derbez et al. 2008; Joblin, Moularat et al. 2010; Moularat, Hulin et al. 2011; Hulin, Moularat et al. 2012). Depuis le CSTB a élaboré un prototype de balise de surveillance intégrant cet indice et constitué de capteurs gaz à base de Polymères Conducteurs Electroniques (PCE), en collaboration avec l'ESIEE Paris (l'Ecole d'Ingénieurs de la Chambre de Commerce et d'Industrie de Paris) (pour la balise) et le Laboratoire de Physico-chimie des Polymères et des Interfaces (LPPI) (pour les PCE). Ainsi des capteurs à base de polypyrrole (PPy) et de Poly-(3,4-éthylènedioxythiophène)-poly(styrènesulfonate) (PEDOT-PSS) ont permis de différencier un environnement contaminé d'un environnement sain. Si ces couches sensibles se sont montrées efficaces pour la détection par l'identification d'une empreinte globale de COV d'origine fongique, elles ne s'avèrent pas encore suffisamment sélectives pour réaliser l'identification de chaque COV, indispensable pour le calcul de l'indice.Dans le cadre de la surveillance de la qualité microbiologique de l'air des environnements intérieurs, cette thèse a pour ambition de prolonger ces travaux en étudiant les mécanismes d'interaction entre COV et PCE en vue de l'application au développement de micro-capteurs chimiques adaptés à la mesure in situ. Cette recherche implique à la fois l'optimisation de la sensibilité et de la sélectivité de ces polymères et le développement d'une matrice de capteurs.Le premier aspect de cette étude a consisté à synthétiser de nouveaux PCE, plus spécifiques sur la base de ceux identifiés comme pertinents lors de la thèse de Joblin en 2011. Ainsi, des polymères, à base de pyrrole fonctionnalisés en position 1 et 3, ont été synthétisés par voie électrochimique. Le PEDOT-PSS, polymère commercial (sous forme de suspension dans l'eau), a, quant-à-lui, été conditionné par différents traitements thermiques.Le second aspect a porté sur l'étude de l'influence de l'exposition des COV à ces PCE sur leurs propriétés physico-chimiques. Ainsi, des caractérisations morphologiques, électrochimiques, optiques ainsi que la variation des propriétés de surface ont permis de mettre en évidence des interactions faibles, en général de type van der Waals ou par liaison hydrogène, entre COV et PCE.Enfin, le dernier aspect a porté sur l'étude expérimentale de la réponse des capteurs en contact avec différents COV issus ou non du métabolisme fongique. Cette dernière étape a permis de vérifier les hypothèses de mécanismes d'interaction. Par ailleurs, la spécificité de la matrice de capteurs vis-à-vis des composés fongiques a été démontrée. Cette matrice de capteurs a également permis d'obtenir des signatures spéci / Conducting polymers can be used as active materials of sensing devices that find application in different areas, such as quality control of products in industries such as food and beverage, cosmetics and solvents, in the monitoring of air quality for environmental and safety purposes, and as an auxiliary tool in the diagnosis of diseases. In spite of this, as a general rule, the details of the prevailing interactions of the volatile compounds and the polymer are not well understood. For this reason, we have focused the work of this thesis on the characterization of the interactions between vapors of volatile organic compounds and thin films of conducting polymers. These films, that were the active components of the sensors, were prepared atop of different geometry of interdigitated electrodes via electropolymerization, where several preparation parameters (such as doping agents nature and concentrations, monomer nature, thermal annealing) were observed to assure an homogeneous growth of the polymeric film. Several characterizations such as electrochemical studies, AFM observations and UV-VIS-NIR spectra studies were used to obtain detailed information about the interaction mechanisms between VOC and conducting polymers. We have also measured the contact angle of water, formamide and diiodomethane deposited on the surface of the polymeric films to evaluate surface free energy (and its acid-base and dispersive components). The selectivity and sensitivity of the polymeric sensors when exposed to different volatile organic compounds (VOCs) have shown to be dependent not only of the properties of the analyzed VOC but also on the nature of the counter-ion used to dope the polypyrrole film. As a final conclusion, we can say that as a result of this work it becomes possible to optimize the design of an arrangement of sensors such that both a better sensitivity and a better selectivity sensitivity to a given chemical environment can be achieved.

High levels of polychlorinated dibenzo-p-dioxins and polychlorinated dibenzofurans (PCDD/Fs) in edible fish in the Baltic Sea have raised health concerns in the Baltic region and the rest of Europe. Thus, there are urgent needs to characterize sources in order to formulate effective mitigation strategies. The aim of this thesis is to contribute to a better understanding of past and present sources of PCDD/Fs in the Baltic Sea environment by exploring chemical fingerprints in sediments, air, and biota. The spatial and temporal patterns of PCDD/F distributions in the Baltic Sea during the 20th century were studied in Swedish coastal and offshore sediment cores. The results showed that PCDD/F levels peaked in 1975 (± 7 years) in coastal and 1991 (± 5 years) in offshore areas. The time trends of PCDD/Fs in the sediment cores also showed that environmental half-lives of these pollutants have been shorter in coastal than in offshore areas (15 ± 5 and 29 ± 14 years, respectively). Consequently, there have been remarkable recoveries in coastal areas, but slower recovery in offshore areas with 81 ± 12% and 38 ± 11% reductions from peak levels, respectively. Source-to-receptor multivariate modeling by Positive Matrix Factorization (PMF) showed that six types of PCDD/F sources are and have been important for the Baltic Sea environment: PCDD/Fs related to i) atmospheric background, ii) thermal processes, iii) manufacture and use of tetra-chlorophenol (TCP) and iv) penta-chlorophenol (PCP), v) industrial use of elementary chlo- rine and the chloralkali-process (Chl), and vi) hexa-CDD sources. The results showed that diffuse sources (i and ii) have consistently contributed >80% of the total amounts in the Southern Baltic Sea. In the Northern Baltic Sea, where the biota is most heavily contaminated, impacts of local sources (TCP, PCP and Chl) have been higher, contributing ca. 50% of total amounts. Among the six sources, only Thermal and chlorophenols (ii-iv) have had major impacts on biota. The impact of thermal sources has, however, been declining as shown from source apportioned time-trend data of PCDD/Fs in Baltic herring. In contrast, impacts of chlorophenol-associated sources generally increased, remained at steady-state or slowly decreased during 1990-2010, suggesting that these sources have substantially contributed to the persistently high levels of PCDD/Fs in Baltic biota. Atmospheric sources of PCDD/Fs for the Baltic region (Northern Europe) were also investigated, and specifically whether the inclusion of parallel measurements of metals in the analysis of air would help back-tracking sources. PCDD/Fs and metals in high-volume air samples from a rural field station near the shore of the central Baltic Sea were measured. The study focused on the winter season and air from the S and E sectors, as these samples showed elevated levels of PCDD/Fs, particularly PCDFs. Several metals were found to correlate significantly with the PCDFs. The wide range of candidate metals as source markers for PCDD/F emissions, and the lack of an up-to-date extensive compilation of source characteristics for metal emission from vari- ous sources, limited the use of the metals as source markers. The study was not able to pin-point primary PCDD/F sources for Baltic air, but it demonstrated a new promising approach for source tracing of air emissions. The best leads for back-tracking primary sources of atmospheric PCDD/Fs in Baltic air were seasonal trends and PCDD/F congener patterns, pointing at non-industrial related thermal sources related to heating. The non-localized natures of the sources raise challenges for managing the emissions and thus societal efforts are required to better control atmospheric emissions of PCDD/Fs. / EcoChange / BalticPOPs