Dissertations / Theses on the topic 'Gas partition'

The influence of basicity, heat treatment as well as different oxygen partial pressures on the phase relationships in the CaO-MgO-SiO2-Cr2O3 slags was studied with a view to control the precipitation of Cr-spinel in the slag phase. The equilibrium phases in CaO-MgO-SiO2-Cr2O3 slag system in the range on 1673-1873 K have been investigated under low oxygen partial pressure as well as in as air atmosphere. In low oxygen partial pressure experiments, a suitable mixture of CO and CO2 was used to control the oxygen partial pressure. The oxygen partial pressure was kept at 10-4 Pa. The Cr2O3 and MgO contents in the slag were fixed to be 6 and 8wt% respectively. The basicity (CaO/ SiO2) of the slag was varied in the range 1.0-2.0. Gas/slag equilibrium technique was adopted to synthesize the slag at a suitable temperature above the liquidus point. One heat treatment procedure is that the samples were heated to and soaked at 1873 K for 24h in order to achieve the equilibrium state and subsequently quenched in water. The other is that the samples were heated to and soaked at 1873 K for 24h, then slow cooled to 1673 K and soaked at this temperature for additional 24h in order to achieve the equilibrium state at lower temperature before quenching in water. The chromium distribution and phase compositions in the quenched slag were studied using scanning electron microscopy (SEM), energy dispersive spectroscopy (EDS) and X-ray diffraction techniques (XRD). FACTsage software was used for the phase equilibrium calculations. The experimental results obtained from the present work are compared with the calculation results from FACTsage software as well as with results from samples directly quenched after soaking at 1873K. It is found that the spinel formation at 1873 K in air atmosphere is favored in the slag basicity range of 1.0 to 1.6. The size of spinel crystals increased drastically after slow cooling followed by annealing compared to samples being quenched after soaking at 1873 K. The amount of foreign elements dissolved in the spinel phase, and matrix phases decreased after slow cooling followed by annealing at lower temperature, resulting in purer phases with less defects. It was found that the amount of foreign elements in the spinel phase, and other phases decreased after soaking at very low PO2. The size of the spinel crystals was found to be larger in samples with low basicity. Spinel phase precipitation has improved in the samples with higher basicities compared to the results obtained in air.
QC 20111208

Heightened concerns for cleaner air and increasingly more stringent regulations on sulphur content in transportation fuels will make desulphurization more and more important. The sulphur problem is becoming more serious in general, particularly for diesel fuels as the regulated sulphur content is getting an order of magnitude lower, while the sulphur contents of crude oils are becoming higher. This thesis aimed to develop a desulphurisation process (based on oxidation followed by extraction) with high efficiency, selectivity and minimum energy consumption leading to minimum environmental impact via laboratory batch experiments, mathematical modelling and optimisation. Deep desulphurization of model sulphur compounds (di-n-butyl sulphide, dimethyl sulfoxide and dibenzothiophene) and heavy gas oils (HGO) derived from Libyan crude oil were conducted. A series of batch experiments were carried out using a small reactor operating at various temperatures (40-100 °C) with hydrogen peroxide (H2O2) as oxidant and formic acid (HCOOH) as catalyst. Kinetic models for the oxidation process are then developed based on 'total sulphur approach'. Extraction of unoxidised and oxidised gas oils was also investigated using methanol, dimethylformamide (DMF) and N-methyl pyrolidone (NMP) as solvents. For each solvent, the 'measures' such as: the partition coefficient (KP), effectiveness factor (Kf) and extractor factor (Ef) are used to select the best/effective solvent and to find the effective heavy gas oil/solvent ratios. A CSTR model is then developed for the process for evaluating viability of the large scale operation. It is noted that while the energy consumption and recovery issues could be ignored for batch experiments these could not be ignored for large scale operation. Large amount of heating is necessary even to carry out the reaction at 30-40 °C, the recovery of which is very important for maximising the profitability of operation and also to minimise environmental impact by reducing net CO2 release. Here the heat integration of the oxidation process is considered to recover most of the external energy input. However, this leads to putting a number of heat exchangers in the oxidation process requiring capital investment. Optimisation problem is formulated using gPROMS modelling tool to optimise some of the design and operating parameters (such as reaction temperature, residence time and splitter ratio) of integrated process while minimising an objective function which is a coupled function of capital and operating costs involving design and operating parameters. Two cases are studied: where (i) HGO and catalyst are fed as one feed stream and (ii) HGO and catalyst are treated as two feed streams. A liquid-liquid extraction model is then developed for the extraction of sulphur compounds from the oxidised heavy gas oil. With the experimentally determined KP multi stage liquid-liquid extraction process is modelled using gPROMS software and the process is simulated for three different solvents at different oil/solvent ratios to select the best solvent, and to obtain the best heavy gas oil to solvent ratio and number of extraction stages to reduce the sulphur content to less than 10 ppm. Finally, an integrated oxidation and extraction steps of ODS process is developed based on the batch experiments and modelling. The recovery of oxidant, catalyst and solvent are considered and preliminary economic analysis for the integrated ODS process is presented.

A new method of in situ extraction of alcohols from fermentation broth was investigated. The extraction method exploited the latent advantages of the non-equilibrium phase interaction of the fluid system in the flash tank to effectively recover the alcohol. Carbon dioxide gas ranging from 4.2L/min to 12.6L/min was used to continuously strip 2 and 12% (v/v) ethanol solution in a fermentor with a recycle. Ethanol and water in the stripped gas was recovered by compressing and then flashing into a flash tank that was maintained at 5 to 70bar and 5 to 55oC where two immiscible phases comprising CO2-rich phase (top layer) and H2O-rich phase (bottom layer) were formed. The H2O-rich bottom layer was collected as the Bottoms. The CO2-rich phase was continuously throttled producing a condensate (Tops) as a result of the Joule-Thompson cooling effect. The total ethanol recovered from the extraction scheme was 46.0 to 80% for the fermentor containing 2% (v/v) ethanol and 57 to 89% for the fermentor containing 12% (v/v) ethanol. The concentration of ethanol in the Bottoms ranged from 8.0 to 14.9 %(v/v) for the extraction from the 2 %(v/v) ethanol solution and 40.0 to 53.8 %(v/v) for the 12% (v/v) fermentor ethanol extraction. The Bottoms concentration showed a fourfold increase compared to the feed. The ethanol concentration of the Tops were much higher with the highest at approx. 90% (v/v) ethanol, however the yields were extremely low. Compression work required ranged from 6.4 to 20.1 MJ/kg ethanol recovered from the gas stream in the case of 12% (v/v) ethanol in fermentor. The energy requirement for the 2% (v/v) extraction was 84MJ/kg recovered ethanol. The measured Joule-Thompson cooling effect for the extraction scheme was in the range of 10 to 20% the work of compressing the gas. The lowest measured throttle valve temperature was -47oC at the flash tank conditions of 70bar and 25oC. Optimization of the extraction scheme showed that increasing the temperature of the flash tank reduced the amount of ethanol recovered. Increasing the pressure of the flash tank increased the total ethanol recovered but beyond 45bar it appeared to reduce the yield. The 12.6L/min carbon dioxide flow rate favored the high pressure(70bar) extraction whiles 4.2L/min appeared to favor the low pressure(40bar) extraction. The studies showed that the extraction method could potentially be used to recover ethanol and other fermentation products.
Master of Science

Petróleo Brasileiro S.A.
O presente trabalho aborda o comportamento da planta de processamento primário com alimentação por fluxo em padrão de golfadas. O fluxo no sistema de tubulações é descrito por um modelo de parâmetros concentrados, fornecendo as características principais necessárias para o controle da planta, e a resposta dinâmica desta pode então ser analisada. Usando a estratégia de controle tradicional verifica-se que as oscilações de fluxo são transmitidas para as vazões de saída de líquido e gás, para obter uma vazão de saída mais estável é permitida a flutuação de carga no separador dentro de uma tolerância, isto é possível reduzindo a atuação do controlador e estabelecendo um controle adicional diretamente na válvula de entrada.
The present work addresses the behavior of a primary processing plant subjected to slug flow pattern at its entrance. The flow in a pipeline system is described by a simplified concentrated parameter model, which preserves the main physical features that are important to control the plant. The dynamic response of the plant is then analyzed. Using a standard control strategy for the gas liquid separator, it is seen that the flow oscillations are transmitted to the liquid and gas outlets. In order to obtain a more stable outlet flow, the liquid level in the separator is then allowed to fluctuate within a given range, by reducing the effect of the controller constants, and establishing an additional control directly on the inlet entrance valve.

Perseguendo politiche comuni per gli Stati membri, l'Unione Europea si è trasformata da unione puramente economica ad unione politica. Tuttavia, per quanto riguarda quest'ultimo aspetto, è stato fatto poco. Lo scetticismo è venuto a caratterizzare il clima politico dell'Unione Europea e l’elevata eterogeneità nei termini degli Stati membri hanno causato difficoltà nel processo decisionale. Questa tesi si concentra sulle politiche europee da tre aspetti: la legittimità, che si riferisce al sostegno politico dei cittadini, il comportamento di voto e di partecipazione dei cittadini. Una delle questioni principali della ricerca riguarda l’esistenza delle basi per la genesi di veri e propri partiti politici europei, come via d’uscita dalla crisi di legittimità dell'Unione Europea. Ci si chiede poi quali sono i principali fattori che influenzano la partecipazione alle elezioni del Parlamento Europeo, dal momento che esso è l'unica fonte diretta di legittimità. Infine, si studiano le cause del gap in affluenza per le elezioni europee e nazionali, guardando la quota di voto del partito. L'argomento principale per l’esistenza dei partiti pan-europei è quello di difendere gli stessi interessi e valori su scala europea. I risultati empirici sottolineano che la polarizzazione di classe sociale, è già presente nei primi 12 Stati membri dell'UE, e anche nei nuovi Stati membri, mentre nelle elezioni del Parlamento europeo gli elettori votano sinceramente. In conclusione: l'Europa soddisfa la base per la creazione di partiti pan-Europei che difendino vere e proprie politiche europee, mirate ai gruppi sociali che rappresentano, come una possibile soluzione per la crisi di legittimità.
By pursuing common policies for its Member States, the European Union moved from being a purely economic union, to being a political one as well. However, little has been done to tackle the latter aspect. Skepticism has come to characterize the political climate of the European Union and high heterogeneity in terms of Member States has induced difficulties in the decision-making process. This thesis focuses on the European Politics from three aspects: legitimacy, which refers to citizens’ political support, voting behavior and turnout. One of the main research questions we address is whether or not the basis for the existence of true European party politics exists, as a way out of the European Union legitimacy crisis. Then, we ask what are the main factors that influence electoral participation in the European Parliament elections since it is the only source of direct legitimacy. Lastly, we investigate what are the causes for the turnout gap across European and National elections, looking at the party vote share. The main argument for pan-European to exist is to defend the same values and interests European-wide. Empirical results point out that social class's polarization already exists in the initial 12 EU Member States, as well as later entries, while in the European Parliament elections voters cast their vote sincerely. We conclude that Europe fulfils the base requirement for the creation of true European politics, party politics and social groups' targeted-policies being a possible solution for the legitimacy crisis.

碩士
國立中興大學
環境工程學系所
97
The source apportionment of dioxin compounds (a group of polyhalogenated compounds) is of interest because of its carcinogenicity to human and animals. Model approach can provide a quantitatively linkage between source and receptor of dioxin compounds. Nonetheless, the magnitudes of the simulated concentrations of dioxin compounds by a model are still underestimated, which was likely due to the lack of a comprehensive emission inventory. Besides, the assumptions made for simulating dioxin might not be appropriated. Therefore, this study is attempted to improve the modeling system of the Gaussian Trajectroy transfer-coefficient model (GTx) for dioxin simulation. The major improvements include an extension of an emission inventory and the introduction of a mechanism for gas/particle partition. Two stages for the emission inventory modification were performed. In the first stage, four pollution sources, including stationary sources, traffic sources, combustion of agriculture waste, and dust from exposed surface, were modeling for the comparison of the predicted concentrations of dioxin with the observations at 19 stations. Using the GTx model cooperated with gas/particle partition mechanism, the results showed that the correlation coefficient of TEQ between observation and simulation is 0.2 ± 0.2% with slightly overestimation. According to the statistical analysis, it was deduced that the amount of dust from exposed surface was affected by the precipitation and, consequently, the amount of precipitation was considered as an index for the exist dust from exposed surface. By adopting the critical value of rainfall of about 7×10-5 mm/s (0.25 mm/hr), the correlation coefficient increased up to TEQ to 0.4 ± 0.2%. Moreover, after incorporating the mechanism for gas/particle partition, the prediction of TEQ was close to the observation and the correlation coefficients of a value of 0.8 was obtained in the particle and total fingerprint matching. In the second stage, six weighted categories using OCDD as index were simulated. The results showed that the correlation coefficients of dioxin congener profiles in particle partition or gas plus particle partition were close to that mentioned in the first stage. But a great increase of correlation coefficient of dioxin congener profiles in individual gas partition reached about 0.7. The results of this study indicated that the predication efficiency of GTx model to simulate the dioxin concentration was improved with the modification of emission inventory and the addition of mechanism of gas/particle partition.

Yes
Literature data on solubilities of adamantane in organic solvents have been used to obtain properties, or descriptors, of adamantane. There is much less data on substituted adamantanes but we have been able to obtain descriptors for some 40 substituted adamantanes. These descriptors can then be used to estimate a wide range of physicochemical, environmental and other properties of the adamantanes. For the first time, the water-solvent partition coefficient and the gas-solvent partition coefficient into a large range of solvents, can be estimated, the latter being equivalent to Henry's Law constants. A variety of other important properties can also be estimated. These include vapor pressures, enthalpies of vaporization and sublimation, partitions from air and from blood into biological tissues, and skin permeability from water. The descriptors themselves are not exceptional. Adamantane itself has a rather low dipolarity, zero hydrogen bond acidity and a very low hydrogen bond basicity, in common with other multicyclic aliphatic compounds. These lead to adamantane being a very hydrophobic compound, as is evident from our estimated water-octanol partition coefficient.
The full-text of this article will be released for public view at the end of the publisher embargo on 24 Dec 2021.

博士
國立成功大學
環境醫學研究所
100
Polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs) have been widely considered as an important hazard to environment and human. Understanding of the fate of PCDD/Fs from source to receiver would be helpful for emission control and environmental impact reduction of PCDD/Fs. This study focuses on (1) the formation of PCDD/Fs in industrial process, (2) controlling PCDD/Fs emission from the potential sources through air pollution control devices (APCD), and (3) the environmental transportation of PCDD/Fs. In recent year, owing to the strict emission regulation, PCDD/Fs emissions from waste incinerators has decreased. In this stage, the focus has shifted to iron ore sinter plant for PCDD/Fs emission. Theoretically, in process suppression of PCDD/Fs generation is the best way to reduce PCDD/Fs emission. However, the PCDD/Fs formation pathway in sintering process is still unconcluded and limits the development of suppression of PCDD/Fs generation in sintering process. Therefore, the first research subject is to study the formation of PCDD/Fs during sinter process was studied. Since the sinter raw mix, (such as iron ores, coke breeze, flux and return fine), which with chlorine, metals and other organic matters have favored de novo synthesis. Moreover, the temperature profile of sinter bed revealed that the temperature of flue gas in the windbox of the later phase of sintering process could reach 400 to 500 C, indicating that the atmosphere of the windbox could be favorable for the de novo synthesis. However, the evidences for the possible de novo synthesis of PCDD/Fs in the windbox are still limited. We took the windbox dust from a commercial sinter plant for direct measurement of ionic and chemical functional group constituents for predicting possible de novo synthesis pathways of dibenzo-p-dioxins and dibenzofurans (PCDD/Fs). We discovered that the abundance in both KCl and NaCl may provide a favorable environment for de novo synthesis of PCDD/Fs in the WB. Al, Fe, K, Ca, and Pb were the top five contents in WB16 dusts, but the co-existence of the above five metal contents need further investigation on their roles in PCDD/F formation processes in the future. Although a low concentration of Cu was detected, it might be of importance to PCDD/Fs formation inside the WB. A total of 29 chemical compounds were identified. Among them, several oxygenated organic compound might be associated with PCDD/F formations at the beginning stage, but the roles of aromatic oxygenates on the formation of PCDD/Fs required further investigation. Finally, possible de novo synthesis pathways of PCDD/Fs were proposed based on the above findings. However, the above pathways are required further laboratory studies for validation before possible formation suppression approaches can be determined. Besides direct suppression of PCDD/Fs generation, the end-of-pipe treatment (air pollution control devices, APCDs) is widely used as a major ways to reduce PCDD/Fs emission nowadays. However, using the data obtained by current flue gas sampling methods to evaluate the PCDD/Fs removal efficiencies of installed APCDs remains potential error. The misestimating of removal efficiencies might cause the unexpected emission of PCDD/Fs into the environment. Therefore, the second part of this study was aimed at developing an approach for correcting the gas and particle partitioning of PCDD/F congeners for samples collected from the flue gas of an iron ore sinter plant. An iron ore sinter plant equipped with an electrostatic precipitator (EP) and a selective catalytic reduction (SCR) was selected. Flue gas samples were collected at EP inlet (EPi), EP outlet (EPo) and SCR outlet (SCRo). Both particle- and gas-phase PCDD/Fs were analyzed for each collected sample. PCDD/F contents in EP ashs (EPash) were also analyzed and used to correct the gas and particle partitioning of PCDD/F congeners of the collected flue gas samples. Results show that PCDD/Fs in the flue gas were dominated by the gas-phase. Before correction, the removal efficiencies for the gas- and particle-phase PCDD/Fs for EP were -58.1% and 64.3%, respectively, and SCR were 39.4% and 83.9%, respectively. The above results were conflict with the expected results for both EP and SCR indicating the need for correcting the gas and particle partitioning of PCDD/F congeners for all collected flue gas samples. After correction, the removal efficiencies become more reasonable for EP (=4.22% and 97.7%, respectively), and SCR (=54.7% and 62.0%, respectively). The above results confirm the feasibility of correcting approach developed by this study. Once PCDD/Fs as well as dioxin-like compounds have entered the atmosphere from the sources, they move from atmosphere to other environmental compartment and eventually entered the food chain. Therefore, understanding their fate in the terrestrial environment also became an important issue. In the third part of this study, the PCDD/Fs as well as dioxin-like compounds concentrations in the ambient air and their impact on vegetation and soil are investigated. Ambient air, vegetation, and soil samples were collected from the vicinity of an industrial complex. For each collected sample, the polychlorinated dibenzo-p-dioxins/dibenzofurans (PCDD/F), coplanar polychlorinated biphenyls (coplanar PCB), brominated dibenzo-p-dioxins/ dibenzofurans (PBDD/F), and polybrominated diphenyl ethers (PBDE) concentrations are analyzed. Principal component analysis (PCA) is adopted to explore the relationships between the concentration of each POP type in the ambient air and those in soil and vegetation. Results showed that atmospheric PCDD/Fs, PBDD/Fs, and PBDEs are dominated by the particle phase. PCDD/Fs in vegetation and soil are contributed by gas-phase and particle-phase PCDD/Fs, respectively. For coplanar PCBs, only the gas-phase coplanar PCBs contribute to the content in vegetation and soil. For PBDD/Fs, both vegetation and soil are contributed by particle-phase PBDD/Fs. PBDEs in vegetation are contributed by both gas- and particle-phase PBDEs, while soil PBDEs are by particle-phase only. The above results are confirmed by comparing with those obtained from theoretical calculations and previous studies.

博士
國立中山大學
環境工程研究所
101
The issues of atmospheric mercury have been discussed more popularly in the world. This study measured atmospheric mercury by using the modified sampling and analytical methods from four cases of small-scale regions to large-scale regions, and further investigated the tempospatial variation of atmospheric mercury, gas-particulate partition, the correlation analysis of mercury concentration with meteorological parameters and criteria air pollutants, the transportation routes of mercury, and the comparison of mercury concentration in urban areas and other stationary sources. First of all, an one-year field measurement results at a semi-conductor manufacturing complex showed that the seasonal averaged concentrations of TGM and Hgp were in the range of 3.30-6.89 and 0.06-0.14 ng/m3, respectively, while the highest 24-hr TGM and Hgp concentrations were 10.33 and 0.26 ng/m3, respectively. Atmospheric mercury apportioned as 92.59-99.01% TGM and 0.99-7.41% Hgp. As a whole, the highest and lowest concentrations of TGM were observed in the winter and summer sampling periods, respectively, while the concentration of Hgp did not vary much seasonally. The highest TGM concentrations were always observed at the downwind sites, indicating that the semi-conductor manufacturing complex was a hot spot of mercury emission source, which caused severe atmospheric mercury contamination over the investigation region. In an unique mercury-contaminated remediation site, an one-year field measurement results showed that the seasonal averaged concentrations of TGM and Hgp were in the range of 5.56-12.60 and 0.06-0.22 ng/m3, respectively, while the seasonal averaged deposition fluxes of dust-fall mercury were in the range of 27.0 to 56.8 g/km2-month. The maximum concentrations of TGM and Hgp were 38.95 and 0.58 ng/m3, respectively. The atmospheric mercury apportioned as 97.42-99.87% TGM and 0.13-2.58% Hgp. As a whole, the concentrations of mercury species were higher in the spring and summer than those in the winter and fall. The southern prevailing winds generally brought higher mercury concentrations, while the northern winds brought relatively lower mercury concentrations, to the nearby fishing villages. The hot spot of mercury emissions was allocated at the southern tip of the abandoned chlor-alkali manufacturing plant. On-site continuous monitoring of TGM at the mercury-contaminated remediation site observed that TGM concentrations during the open excavation period were 2 to 3 times higher than those during the non-excavation period. In a heavily polluted industrial city, Kaohsiung, field measurement results showed that TGM and Hgp concentrations were in the range of 2.38-9.41 and 0.02-0.59 ng/m3 with the highest concentrations of 9.41 and 0.59 ng/m3, respectively. Moreover, the partition of atmospheric mercury was apportioned as 92.71-99.17% TGM and 0.83-7.29% Hgp. As a whole, the concentrations of mercury species in the dry season were higher than those in the wet season, no matter of TGM or Hgp concentration. The TGM and Hgp concentrations at Hsiao-kang site was the highest in Kaohsiung City. The hot spots of atmospheric mercury were allocated at two regions in Kaohsiung City, including a steel industrial complex in the south and a petrochemical industrial complex in the north. In a coastal site of the Penghu Islands, the field measurement results showed that the average TGM concentration during the monitoring periods was 3.17±1.17 ng/m3 with the range of 1.17-8.63 ng/m3, as the highest concentration being observed in spring, while the average TGM concentrations in the daytime were typically higher than that at nighttime. Moreover, the lowest average TGM concentration of 1.81±0.15 ng/m3 was observed in summer. The backward trajectory simulation results showed that the elevated TGM concentrations could be transported from either North China, East China, or South China to the Penghu Islands, while those originated from South China Sea had the lowest contribution to the TGM levels of the Penghu Islands. Therefore, prevailing wind direction and air mass transportation routes potentially playing the critical roles on the variation of TGM concentration at the Penghu Islands. Furthermore, correlation analysis results indicated that the TGM concentration correlated positively with SO2, NOx, CO, ambient temperature, UVB and negatively with O3, relative humidity, and wind speed. While, Hgp correlated positively with SO2, NOx, O3 and negatively with ambient temperature, relative humidity, and wind speed.

Yes
We have set out an equation for partition of 87 neutral molecules from water to o-nitrophenyl octyl ether, NPOE, an equation for partition of the 87 neutral molecules and 21 ionic species from water to NPOE, and an equation for partition of 87 neutral molecules from the gas phase to NPOE. Comparison with equations for partition into other solvents shows that, as regards partition of neutral (nonelectrolyte) compounds, NPOE would be a good model for 1,2-dichloroethane and for nitrobenzene. In terms of partition of ions and ionic species, NPOE is quite similar to 1,2-dichloroethane and not far away from other aprotic solvents such as nitrobenzene.

碩士
國立成功大學
環境工程學系碩博士班
95
In order to investigate K and R municipal solid waste incinerators (MSWIs) PCDD/Fs of flue gas effect on the surrounding environment. This research focus on K and R MSWIs`s ambient air, Gas/Particle Partitions and Size Distributions of PCDD/Fs. The results are as follows: 　K MSWI average concentration in ambient air of PCDD/Fs is 0.0749 pg I-TEQ/Nm3; and R MSWI is 0.0727 pg I-TEQ/Nm3. 　K MSWI Gas/Particle Partitions of PCDD/Fs average concentration is 0.0358 and 0.0283 pg I-TEQ/Nm3; R MSWI is 0.0315 and 0.0195 pg I-TEQ/Nm3. K MSWI Gas/Particle Partitions simulation model of PCDD/Fs average concentration is 0.0405 and 0.034 pg I-TEQ/Nm3; R MSWI is 0.042 and 0.0305 pg I-TEQ/Nm3. To compare surveying and simulation value, that can get the sampling and analysis of Artifact. 　In MSWI, the size distributions of total particle mass is showed of two peaks, the total particle mass range 3.2~36.5 and 0.52~1.8 μm; the total PCDD/Fs and total I-TQE PCDD/Fs are showed of one peak, the total PCDD/Fs and total I-TQE PCDD/Fs range 0.31~1.0 μm. 　In MSWI, the cumulative percentage of the total particle mass, total PCDD/Fs and total I-TQE PCDD/Fs, the average MMD are 5.77, 0.77 and 0.78 μm. In MSWI, the average MMDo andδg,o of the total particle mass, total PCDD/Fs and total I-TQE PCDD/Fs, the value are (5.77, 0.77 and 0.71) and (5.17, 2.68 and 2.32) μm；the average MMDf and δg,f are (0.98, 0.62 and 0.59) and (1.91, 2.04 and 1.98) μm；the average MMDc and δg,c are (12.78, 7.44 and 8.74) and (2.72, 2.75 and 2.63) μm. 　In all of sampling site, the total PCDD/Fs of MMDo value are less than total particle mass of MMDo value. According to the total particle mass and the total PCDD/Fs of theδg,o, it indicates that the distribution range of small particles is larger than the coarse particles. And the range of particle distribution is quite large in atmosphere. Small particle has higher PCDD/Fs concentration than that of larger particle. It could be due to the small particle has larger surface and adsorb more PCDD/Fs on it.

碩士
國立雲林科技大學
環境與安全衛生工程系
106
Previous PM2.5 studies have shown a higher mass proportional on secondary aerosols (~50% of PM2.5) in southern Taiwan. The study attempts to investigate the sampling artifacts of secondary aerosols and its oxidational states in southern Taiwan (Douliou areas). The experiments, utilized by annular denuder sampler (ADS) and PEM sampler (ADS without denuders), applied on day/night samplings to examine the sampling artifacts (errors) and the distribution of gas/solid phases on secondary aerosols. Measurements included PM2.5 concentrations, levoglucosan (Levo.), water-soluble ions, and inorganic gases have been discussed. The results presented that mass concentrations of PM2.5 on PEM samplings were higher than that on ADS samplings (29.8 µg/m3 vs. 25.9 µg/m3). The variations might cause by adsorption denuders first collecting gas phase pollutions on ADS rather than simultaneous collecting of gaseous and particle phases on PEM, which easily overvalued in secondary aerosols on PEM samplings (positive artifact ~15%). Meanwhile, volatile secondary aerosols influenced by ambient temperature to loss their concentrations on filters (blow-off effect, a negative artifact) have been investigated. The study was used by day (~1.7°C) and night (~0.9°C) samplings to minimized variation of ambient temperature during sampling periods. Significant nitrate exhibited a loss of 36% and 16% proportions, and ammonia ion lost 22% and 11% in summer (~30°C) and winter (~20°C), respectively. Sulfate ion could be ignored when the ambient temperature lower than 20°C (loss only 3~5% at summer time). The study indicated that secondary aerosol carried a blow-off effect, which easily caused an under-estimation of secondary aerosols on PM2.5 samplings. Moreover, the study evaluated the conversion rate of nitrogen and sulfur (Fn and Fs). Both conversion rates showed a positive correlation with humidity in spring season, which enhanced formation of solid phase leading a higher PM2.5 concentration in the area. The conversion rate of sulfur (Fs) was distinctly higher in Douliou, and the value of Fs at night higher than at daytime. Furthermore, the study showed a good correlation between nitrous acid (HONO) and biomass marker of levoglucosan (R2~0.66), even the springtime was not the season of rice straw burning. Those HONO abundance (1-4ug/m3, 2-7 times higher than background) might be deriving from certain sources of biomass emissions. The HONO is a dominant precursor of ·OH radicals in atmosphere. Hydroxyl radical always play a major driving force to form the secondary aerosol of PM2.5 (might be first oxidized SO2 to sulfate, and releasing HO2 radical further transferred NO to NO2). However, the photochemical reaction in atmospheres is very complicated, and further study regarding daytime sources of HONO and mechanism of secondary aerosols formation is continually demanded.

碩士
中山醫學大學
公共衛生學系碩士班
106
The purpose of this study is to investigate the differences in compositions and gas/particle partitioning for polycyclic aromatic hydrocarbons (PAHs) in three different regions. During the period of 2014 to 2017, samples (gas phase and total suspended particles) were collected from coastal areas in Yunlin county, inland areas of Yunlin county, and inland areas of Taichung city. Twenty-nine PAHs from samples were analyzed by gas chromatography coupled with mass spectrometry (GC/MS). The differences in compositions, characterisitic ratios, gas/particle portioning coefficients, and the aging degree of PAHs between day and night, as well as the different seasons in three different regions, were discussed. The results of PAH compositions show that all three regions were affected by diesel engine emissions, while coastal areas in Yunlin county in autumn and winter were further affected by industrial combustion. The results of characterisitic ratios show that the PAH contribution sources were mainly from industrial combustion in coastal sites of Yunlin county, while the sources were from coal combustion and volatilization of petroleum hydrocarbons in inland sites of Yunlin county and Taichung city. The logKP-logPLo and logKp-logKoa models were used to discuss the equilibrium status of gas-particle partitioning of PAHs in three different regions. The distributions of gas-particle partitions in inland areas of Taichung city were closer to the equilibrium status than the other two regions. However, compared to other seasons, the distributions of gas-particle partitions in coastal areas and inland areas of Yunlin county was closer to the equilibrium status of spring. The results of the aging indices in three different regions show that the degree of aging for aerosols in the inland areas of Taichung city became more obvious than the other two regions.