This study set out to examine the Taiwan college students¡¦ underlying knowledge of English relative clauses in attempt to see what the factor(s) is/are that constrain(s) the learners¡¦ language acquisition process, whether it is the universal factor, the native language, or human general problem solving skill. Three predictor hypotheses were used in this investigation: NAPH, PDH, and SOHH, which are motivated by different theoretical backgrounds. The NPAH is based on the typological markedness, the PDH is based on the notion of human limited capacity of short term memory, and SOHH the combination of NPAH and PDH, and the structural difficulty of relative clause. The data from 84 non-English major college students of NSYSU were elicited using three kinds of tasks: sentence combination test, Chinese-English translation test, and grammaticality judgment test. 12 types of English relative clauses were analyzed in this study, namely SS, SO, SIO, SOPREP, SGEN, SOCOMP, OS, OO,OIO, OOPREP,OGEN, OOCOMP. In addition, the learners¡¦ avoidance strategies were extensively analyzed to see what was actually avoided as they were engaged in the formation of English relative clauses. Implicationally, the results suggest that Universal Grammar may be still operative in the minds of the adult FL language learners. Overall, we have the following findings: 1.The learners¡¦ acquisition of relative clauses is largely constrained by the universal markedness by NPAH, except GEN, and the order between IO and OPREP. 2.The retention of pronoun is largely constrained by the linguistic universals of NPAH, but Chinese also has certain influence on the learners¡¦ choice of supplying resumptive pronoun. 3.The learners largely did experience more difficulty in center-embedded relative clauses, which matches PDH. 4.Largely, SOHH is a valid prediction of the learners¡¦ acquisition of relative clauses. 5.The learners tended to avoid relativization on the positions low on the NPAH, except GEN. 6.The learners did frequently avoid OCOMP relatives and center-embedded relative clauses.

<p> The profiles of polycyclic aromatic compounds (PAC) were compared in three separate studies involving air samples collected in urban and rural locations across Canada. In the Freelton/Pier 25 study (conducted near Hamilton, Ontario) a total of 32 NPAH were analyzed for in 12 composite air particulate samples from Freelton (a rural site) and Pier 25 (an urban site) using negative ion chemical ionization gas chromatography-mass spectrometry.</p> <p> The NPAH levels at the two sites were found to be similar except for the two samples at Pier 25. These results were consistent with the PAH levels determined previously which showed significantly increased levels at Pier 25 under the same condition when the sampling site was downwind of the urban/industrial core. NPAH may be significant contributors to mutation induction due to exposures to ambient air since the offspring of male mice from the Pier 25 site exposed to ambient air showed inherited mutation rates about 2 times greater than offspring of mice exposed at the Freelton site. NPAH are highly mutagenic and carcinogenic compounds that act via reductive metabolism and can be readily metabolized to potent reactive intermediates within all cells.</p> <p> Concentration data for a set of polycyclic aromatic compounds were obtained for samples collected during the day and night during a study in Simcoe (rural) and Toronto (urban) as well as at three sites in British Columbia as part of the Pacific 2001 study (Slocan (urban), Langley (suburban/rural) and Sumas (rural)). The conversion of these concentration data into particulate loadings data (using elemental carbon data) enabled us to perform a number of unique interpretations and analyses of the data sets. Since particulate loadings values are not affected by air dispersion it was possible to compare samples and individual PAC across a range of samples.</p> <p> Principal components analysis of the loadings data showed dramatic differences between the urban and rural sites from each study. Day-night samples at the rural sites also showed dramatic profile differences. The urban sites showed significantly less differences in profiles, consistent with lesser degree of air transformation and closer proximities to sources.</p> / Thesis / Master of Science (MSc)

Les Hydrocarbures Aromatiques Polycycliques (HAP) sont des polluants dont la concentration est réglementée dans l’air ambiant, en raison de leurs caractères cancérigène et/ou mutagène. Ces composés, émis lors de combustions incomplètes, peuvent réagir dans l’atmosphère avec les principaux oxydants atmosphériques pour former des dérivés oxygénés (OHAP) et nitrés (NHAP), dont la toxicité est potentiellement encore plus importante. Dans ce contexte, ce travail a été réalisé par la combinaison de deux approches complémentaires : études de réactivité en atmosphère contrôlée et études de terrain, afin de mieux comprendre le devenir (formation/dégradation) de ces composés dans l’atmosphère. Ainsi, des particules naturelles, prélevées dans l’air ambiant, ont été exposées en réacteur à différents oxydants atmosphériques(O3, OH et NO2/O3). Les résultats montrent la dégradation effective des HAP et le benzo[a]pyrène, seul HAP réglementé aujourd’hui en Europe, apparait comme le composé le plus réactif. De plus, la formation significative de OHAP et NHAP a été mise en évidence, même si les quantités observées sont trop faibles pour boucler le bilan de masse, illustrant la formation de produits non détectés/détectables dans ce travail. La dégradation des HAP ayant été démontrée sur des particules naturelles, la question du lieu majoritaire de dégradation (atmosphère/support de prélèvement) a été étudiée au cours de différents échantillonnages atmosphériques, mettant en parallèle des préleveurs équipés ou non de pièges à ozone de type dénudeur. Ces études, bien que n’ayant pas permis de répondre définitivement à cette question, ont montré la formation de certains dérivés de HAP sur les supports d’échantillonnage. Suite à ces conclusions, des mesures ont été déployées sur le terrain, sur des sites de typologies différentes dans la région parisienne. Les concentrations en HAP, OHAP et NHAP mesurées se sont avérées 10 fois plus importantes sur un site trafic que sur un site périurbain. De plus, les différentes espèces mesurées sur chacun des sites ont montré que, contrairement aux HAP et OHAP, les NHAP majoritaires différaient selon la typologie du site. Ainsi, le site trafic a été identifié comme étant majoritairement influencé par des sources primaires, à l’opposé du site périurbain sur lequel les espèces secondaires étaient plus abondantes. Les études granulométriques ont montré que la distribution entaille des OHAP et NHAP particulaires était liée à leurs origines (primaire/secondaire). De plus, les OHAP et NHAP apparaissent associés à 85 % à la fraction la plus fine de l’aérosol (Dp < 2,5 µm), accentuant l’intérêt de leur étude d’un point de vue sanitaire. Enfin, la combinaison de l’étude de la distribution granulométrique de certains composés identifiés comme primaire ou secondaire, à celle des profils chimiques des NHAP ouOHAP, a permis de proposer des pistes quant à l’origine majoritaire de ces familles de composés dans l’air ambiant. / Polycyclic Aromatic Hydrocarbon (PAH) concentrations are regulated in ambient air because of theirmutagenic and carcinogenic properties. They are largely emitted by combustion processes and may react withmain atmospheric oxidants to form oxygenated (OPAH) and nitrated (NPAH) derivatives, which can be moretoxic than their parent PAHs. In this work, PAH derivatives were studied using the combination of twocomplementary approaches: laboratory reactivity experiments in controlled conditions and field studies, inorder to better understand their source and fate in the atmosphere. Reactivity study of PAHs adsorbed onnatural particles was carried out by exposing ambient particles to atmospheric oxidants (O3, OH and NO2/O3)in appropriate reactors. Large decays of PAH concentrations were observed, benzo[a]pyrene (B[a]P, which isthe only regulated PAH in Europe), appearing as the most reactive. The formation of OPAHs and NPAHs wasshowed. Nevertheless, quantities of both NPAHs and OPAHs formed were not sufficient to explain the totalamount of PAHs that react, highlighting the formation of other compounds, not detected in this work. PAHdegradation may occur in the atmosphere during the transport of air masses or directly on the filter during thesampling. The study of the major degradation processes was performed during field studies, using two highvolume samplers, one being equipped with an ozone scrubber. Even if, results were not enough to clearlyconclude about the relative importance of both degradation processes, the significant formation of some PAHderivatives on the sampling filter was observed. Then, field campaigns were led on different typologies ofsampling sites around Paris. PAH, OPAH and NPAH concentrations were about ten times higher at traffic sitethan at the suburban one. Moreover, for both OPAHs and PAHs, the major compounds were similar at bothsites, in contrary to the case of NPAHs that appeared different. The traffic site appeared strongly influenced byprimary emissions, whereas high amounts of secondary species were quantified at suburban site. Particle sizedistribution of OPAHs and NPAHs showed their strong association to the finest part of aerosols (Dp < 2.5 μm),highlighting the strong interest of this study considering sanitary impacts. Finally, the study of the particle sizedistribution of primary and/or secondary identified compounds, combined with chemical NPAH and OPAHprofiles, allowed to provide indications about the major origin of PAH derivatives in the atmosphere.