Dissertations / Theses on the topic 'Photochemical model'

Halogen-driven ozone and nonmethane hydrocarbon losses in springtime Arctic boundary layer are investigated using a regional chemical transport model (CTM). Surface observation of O3 at Alert and Barrow and aircraft observations of O3 and hydrocarbons during the TOPSE experiment from February to May in 2000 are analyzed. We prescribe halogen radical distributions based on GOME BrO observations and calculated or observed other halogen radical to BrO ratios. GOME BrO shows an apparent anti-correlation with surface temperature over high BrO regions. At its peak, area of simulated near-surface O3 depletions (O3 LT 20ppbv) covers GT 50% of the north high latitudes. Model simulated O3 losses are in agreement with surface and aircraft O3 observations. Simulation of halogen distributions are constrained using aircraft hydrocarbon measurements. We find the currently chemical mechanism overestimate the Cl/BrO ratios. The model can reproduce the observed halogen loss of NMHCs using the empirical Cl/BrO ratios. We find that the hydrocarbon loss is not as sensitive to the prescribed boundary layer height of halogen as that of O3, therefore producing a more robust measure for evaluating satellite column measurement. Tropospheric tracer transport and chemical oxidation processes are examined on the basis of the observations at northern mid-high latitudes and over the tropical Pacific and the corresponding global 3D CTM (GEOS-CHEM) simulations. The correlation between propane and ethane/propane ratio is employed using a finite mixing model to examine the mixing in addition to the OH oxidations. At northern mid-high latitudes the model agrees with the observations before March. The model appears to overestimate the transport from lower to middle latitudes and the horizontal transport and mixing at high latitudes in May. Over the tropical Pacific the model reproduces the observed two-branch slope values reflecting an underestimate of continental convective transport at northern mid-latitudes and an overestimate of latitudinal transport into the tropics. Inverse modeling using the subsets of observed and simulated data is more reliable by reducing (systematic) biases introduced by systematic model transport model transport errors. On the basis of this subset we find the model underestimates the emissions of ethane and propane by 14 5%.

Approved for public release; distribution is unlimited<br>The production of nitric oxide by soft solar X-rays in the E-region of the ionosphere is investigated. An empirical expression for the variation in X-ray flux as a function of F10.7 is determined. This expression is incorporated into a one-dimensional diffusive photochemical model to compute nitric oxide densities. No results of these calculation are compared with NO observation from the Solar Mesosphere Explorer satellite. Variations of X-ray flux by a factor of 30 over the solar cycle can explain the observed variation in nitric oxide densities.<br>http://archive.org/details/investigationofp00duma<br>Lieutenant, United States Navy

Thesis (Ph. D.)--Earth and Atmospheric Sciences, Georgia Institute of Technology, 2006.<br>Wang, Yuhang, Committee Chair ; Black, Robert, Committee Member ; Curry, Judith, Committee Member ; Huey, Greg, Committee Member ; Russell, Armistead G, Committee Member. Includes bibliographical references.

The functionality of devices that utilise TiO2 is heavily influenced by the interactions which occur at the surface and interface. Developing a full mechanistic understanding of these interactions is essential, and the focus of the work presented in this thesis. The interactions of phenylphosphonic acid (PPA) and [C4C1Im][BF4] with the surface of anatase(101) have been investigated using X-ray photoelectron spectroscopy (XPS) and near edge X-ray absorption fine structure (NEXAFS) spectroscopy because of their potential applications in dye-sensitised solar cells. XPS data suggests that at 0.15 monolayer (ML) coverage PPA adsorbs in a bidentate geometry following the deprotonation of both P-OH groups. At 0.85 ML coverage there is a shift to a mixed bidentate/monodentate binding mode. NEXAFS spectroscopy data shows that the phenyl ring is oriented 65 ±4 away from the surface plane and twisted 57 ±11 away from the [101] azimuth. [C4C1Im][BF4] is found to order at the surface of anatase(101) via electrostatic attraction only at low coverages, with the imidazolium ring oriented 32 ± 4 from the surface. XPS data suggests that the anion undergoes a surface induced degradation to form BF3, resulting in incorporation of F into O vacancies. The behaviour of metallic clusters supported on metal oxide supports and the nature of the crystal structure modification of TiO2 following doping with impurity ions both have important implications in catalysis. XPS and scanning tunnelling microscopy (STM) data show that the interaction of Ag with the anatase(101) surface leads to a metal-surface charge transfer, as evidenced by the reduction of Ti4+ to Ti3+, and the formation of 3D size limiting clusters. Under exposure to 3 mbar CO/H2O, partial oxidation of the Ag clusters in conjunction with the formation of a transient Ag-carbonyl species is observed. Upon returning to ultra-high vacuum these species disappear. XPS and photoelectron diffraction (PhD) have been employed and show that nitrogen doping results in an additional Ti species due to TiO2-N. XPS suggests that nitrogen exists in substitutional sites, a conclusion which is reinforced by the PhD data where the N 1s and O 1s modulation functions exhibit similarities. Theoretical modulation functions are yet to be calculated and future work will aim to provide quantitative information regarding the substitutional nature of this system. The effect of adventitious carbon on Ti implants has been modelled by studying peptide adsorption on single crystal TiO2, both as-prepared and pyrocatechol capped. XPS shows that pyrocatechol successfully prevents the adsorption of adventitious carbon species from air and leads to a greater uptake of RGD, which bonds to Ti atoms via the deprotonated carboxylate groups. An increased uptake of RGD is also observed on the SLActive surface and we conclude that the chemistry of the hydrocarbon overlayer governs the uptake of RGD, and may affect osseointegration.

The objective of this study was to determine the photothermal and photochemical tissue response to carbon nanotube inclusion in laser therapy using experimental and computational methods. In this study, we specifically considered varying types and concentrations (0.01-1 mg/ml) of carbon nanotubes (CNTs), e.g., multi-walled carbon nanotubes (MWNTs), single-walled carbon nanotubes (SWNTs), and single-walled carbon nanohorns (SWNHs). In order to determine the photothermal effect of CNT inclusion, the thermal conductivity and optical properties of tissue representative phantoms with CNT inclusion were measured. Thermal conductivity of tissue phantoms containing CNTs was measured using the hot wire probe method. For identical CNT concentrations, phantoms containing MWNTs had the highest thermal conductivity. Optical properties (absorption and reduced scattering coefficients) of solutions and tissue phantoms containing carbon nanotubes were measured with spectrophotometry and determined by the inverse adding doubling (IAD) method. Inclusion of CNTs in phantoms increased light absorption with minimal effect on scattering and anisotropy. Light absorption of MWNTs was found to be higher than SWNTs and SWNHs. The photochemical response to laser irradiation (wavelength 1064 nm) of CNTs was measured with spin-trap electron paramagnetic resonance (EPR) spectroscopy. Only SWNHs appeared to produce significant levels of ROS production in response to laser excitation in the presence of NADH. We detected the predominant presence of trapped hydroxyl radical (•OH) with a trace of the trapped super oxide (O2•-) radical. These free radicals are highly reactive and could be utilized to cause targeted toxicity to cancer cells. The distribution of CNTs at the cellular level, in phantoms, and in kidney tumors was measured using transmission electron microscopy (TEM) imaging. Samples were imaged following various time periods (2-48h) of incubation and CNTs were observed inside the cell cytoplasm, nucleus, vacuole, and outside cells for the above mentioned time periods. CNTs in phantoms and tumor tissue were randomly and uniformly distributed in the entire volume. Computational model geometries were developed based on CNTs distribution in cells, tissue phantoms, and kidney tumor tissue. In the computational part of this research the temperature response to laser irradiation alone or with CNT inclusion was determined using Penne's bioheat equation which was solved by finite element methods. Experimentally measured thermal conductivity and absorption and reduced scattering coefficients were used as input parameters in Penne's bioheat equation. The accuracy of the model predicted temperature distribution was determined by comparing it to experimentally measured temperature in tissue phantoms and kidney tumors following CNT inclusion and laser therapy. The model determined temperature distribution was in close correspondence with the experimentally measured temperature. Our computational model can predict the effectiveness of laser cancer therapy by predicting the transient temperature distribution.<br>Ph. D.

We investigate the solar cycle modulation of the quasi-biennial oscillation (QBO) in stratospheric zonal winds and its impact on stratospheric ozone with an updated version of the zonally averaged CHEM2D middle atmosphere model. We find that the duration of the westerly QBO phase at solar maximum is 3 months shorter than at solar minimum, a more robust result than in an earlier CHEM2D study due to reduced Rayleigh friction drag in the present version of the model. The modeled solar cycle ozone response, determined via multiple linear regression, is compared with observational estimates from the combined Solar Backscattered Ultraviolet (SBUV/2) data set for the period 1979–2003. We find that a model simulation including imposed solar UV variations, the zonal wind QBO, and an imposed 11-year variation in planetary wave 1 amplitude produces a lower stratospheric ozone response of ∼2.5% between 0 and 20°S and an upper stratospheric ozone response of ∼1% between 45 and 55 km, in good agreement with the SBUV-derived ozone response. This simulation also produces an (enhancement/reduction) in the (lower/upper) stratospheric temperature response at low latitudes compared to the effects of solar UV variations alone, which are consistent with model vertical velocity anomalies produced by the solar-modulated QBO and imposed changes in planetary wave forcing.

Orientadora: Profa Dra Cláudia Boian<br>Dissertação (mestrado) - Universidade Federal do ABC, Programa de Pós-Graduação em Ciência e Tecnologia Ambiental, 2017.<br>De acordo com o Decreto Estadual nº. 52469/07, a Região do Grande ABC (RGABC) encontra-se saturada por ozônio (O3) e apresenta peculiaridades em relação a outros locais da Região Metropolitana de São Paulo (RMSP), porque além de uma frota veicular significativa, também possui um forte caráter industrial, com a presença do Polo Petroquímico de Capuava (PPCP) na divisa dos municípios de Mauá e Santo André, em uma área residencial densamente ocupada. Os objetivos deste trabalho foram simular a qualidade do ar para O3 na RGABC, através do uso do modelo fotoquímico de qualidade do ar CIT (Caltech Institute Technology), considerando três cenários para avaliar a contribuição individual das emissões das fontes móveis ou fixas e de ambas para a formação do O3 e avaliar os efeitos da circulação meteorológica de brisa marítima no transporte de O3 e precursores. O período de estudo foi de 28 de setembro a 01 de outubro de 2011 quando houve ultrapassagens do padrão de qualidade e/ou do nível de atenção na RGABC. Os resultados mostraram que durante o período da tarde quando a atividade fotoquímica é mais intensa, as direções preferenciais dos ventos foram de noroeste (NW) e sudoeste (SW) com velocidades dos ventos variando de condições de aragem a brisa forte (0,5 a 8,8 m/s). Neste período a região estava sob o efeito da produção local e de transporte de O3 e precursores provenientes das sub-regiões oeste, norte e sudoeste da Região Metropolitana de São Paulo (RMSP) e também da cidade de São Paulo. Nos períodos da madrugada, manhã e noite a direção preferencial dos ventos foi de sudeste (SE), fazendo com que a RGABC se tornasse exportadora de poluentes. Em nível local a região mais afetada pelo efeito de transporte proveniente da área fonte (PPCP), quando sob efeito de brisa marítima, foi a cidade de São Caetano Sul. Considerando este período específico de simulação, a comparação entre os três cenários em geral mostrou concentrações mais altas na pluma de O3 para o cenário 3 (fontes móveis + fixas) seguido pelos cenários 1 (fontes móveis) e 2 (fontes fixas), mostrando que as emissões de hidrocarbonetos (HC) da fonte fixa foi mais significativa do que as de óxido de nitrogênio (NO) para a formação do O3. Assim, este trabalho mostrou que é de grande importância a avaliação da contribuição das emissões tanto das fontes móveis quanto fixas na RGABC, uma vez que os poluentes emitidos e gerados terão impactos não somente a nível local.<br>According to the State Decree nº. 52469/07, the Great ABC Region (GABCR) is satured with ozone once it presents peculiarities in relation to other locations in the Metropolitan Region of São Paulo (MRSP), as a significantly high vehicle fleet, it also has a strong industrial character, with the presence of the Petrochemical Capuava Complex (PCPC) on the border between the cities of Mauá and Santo André, a densely occupied residential area. The objectives of this work were to simulate air quality for O3 in GABCR through the use of the CIT (Caltech Institute Technology) air quality model, considering three scenarios to evaluate the individual contribution of emissions from mobile and/or fixed sources for the formation of O3 and to evaluate the effects of the meteorological circulation of sea breeze on the transport of O3 and precursors. The study period was from September 28 to October 1, 2011 when there were exceedances of the quality standard and/or level of attention in the GABCR. The results showed that during the afternoon when the photochemical activity is more intense, the main wind directions were northwestern (NW) and southwestern (SW) with varying wind velocities from breezes to strong breezes (0.5 to 8.8 m/s). In this period the region was under the effect of local production and transport of O3 and precursors from the western, northern and southwestern suburbs of the MRSP and also from the city of São Paulo. In the early morning, morning and night the main direction of the winds was of southeast (SE), causing the GABCR to become exporter of pollutants. At the local level, the region most affected by the transport effect from the source area (PPCP), when under sea breeze, was the city of São Caetano Sul. Considering this specific simulation period, the comparison between the three scenarios in general showed higher concentrations in the O3 plume for scenario 3 (mobile + fixed sources) followed by scenarios 1 (mobile sources) and 2 (fixed sources), showing that HC emissions from the fixed source was more significant than those of NO for O3 formation. Thus, this work showed that it is of great importance to evaluate the contribution of emissions from both mobile and fixed sources in the GABCR, since the generated and emitted pollutants will have impacts not only at the local level.

A megacity is generally defined as a city that, together with its suburbs or recognised metropolitan area, has a total population of more than 10 million people. Air pollution in megacities is a major concern due to large increases of populations over the past decades. Increases of air pollution result from more anthropogenic emission sources in megacities, which include energy production, transportation, industrial activities and domestic fuel burning. In the developing parts of Africa, urbanisation is increasing rapidly, with growth rates of populations in cities of up to 5% per annum. The major driving forces for these population increases in African countries can be attributed to population growth, natural disasters and armed ethnic conflicts. In South Africa, 62% of the total population lived in cities in 2010. The rate of urbanisation growth is predicted to be 1.2% per annum. The largest urbanised city in South Africa is the Johannesburg-Pretoria conurbation (referred to as Jhb-Pta megacity) that has more than 10 million inhabitants. Johannesburg is considered to be the central hub of economic activities and -growth in South Africa. The larger conurbation includes all the suburbs of Johannesburg and Pretoria. In South Africa, household combustion and traffic emissions are major sources of pollutants in urbanised areas. The major pollutants emitted from these activities include nitrogen oxide (NO), nitrogen dioxide (NO 2 ), sulphur dioxide (SO2 ), carbon monoxide (CO), particular matter (PM) and various organic compounds. The Jhb-Pta megacity is also located relatively close to large industrialised regions in South Africa, i.e. the Mpumalanga Highveld and the Vaal Triangle. Very few air quality modelling studies have been conducted for the Jhb-Pta megacity. According to the knowledge of the author, no literature existed in peer-reviewed publications at the time of the study. An in-depth modelling study was therefore conducted to assess the current state of air quality within the Jhb-Pta megacity. The main objectives were to optimise an existing photochemical box model for the Jhb-Pta megacity and to utilise the model to investigate the photochemical processes in the Jhb-Pta megacity and surrounding areas. In this investigation, ground-based measurements of criteria atmospheric pollutant species representative of the Jhb- Pta megacity were obtained to utilise as input data in the model, as well as to compare to results determined with the model. From the ground-based measurements, the possible contribution of the Jhb-Pta megacity to the NO2 hotspot observed over the South African Highveld from satellite retrievals was also contextualised. Five ground-based monitoring sites were situated strategically within the boundaries of the Jhb- Pta megacity to measure the direct influences of urban air pollution, e.g. traffic emissions, biomass burning and residential pollution. One measurement site was situated outside the modelling domain in order to collect rural background data in close proximity to the Jhb-Pta megacity. All the air quality stations continuously measured the criteria pollutants NOx, SO2 and O3. In addition, benzene, toluene, ethylbenzene and xylene (BTEX) were measured at four sites. Passive sampling of NOx, SO2 , O3 and BTEX was also conducted in March and April 2010. Active data was obtained for March to May 2009, since no active measurements were available for the same year that passive sampling was performed due to logistical reasons. Meteorological parameters that included temperature, pressure and relative humidity were also measured at the monitoring stations Ground-based measurements provided a good indication of the state of the air quality in the Jhb-Pta megacity. The air quality levels of NO2 , SO2 , O3 and BTEX could be compared to other cities in the world. A distinct diurnal cycle was observed for NO2 at most of the stations. An early morning peak between 6:00 and 9:00 coincided with the time that commuters travel to work, whereas an evening peak between 18:00 and 21:00 could be attributed to traffic emissions and household combustion. Levels of O3, which is a secondary pollutant, peaked between 13:00 and 15:00. This diurnal pattern could be attributed to the photochemical formation of O3 from precursor species NO and VOCs. Toluene was predominantly higher than the other BTEX species. Benzene and xylene concentrations were in the same order, while the lowest levels were measured for ethyl benzene Ground-based measurements also indicated that the NO2 Highveld hotspot, which is well known in the international science community due to its prominence in satellite images, is accompanied by a second hotspot over the Jhb-Pta megacity. Peak NO2 pollution levels in the Jhb-Pta megacity exceeded the maximum daily Highveld values during the morning and evening rush hours. This result is significant for the more than 10 million people living in the Jhb-Pta megacity. Although satellite instruments have been extremely valuable in pointing out global hotspots, a limitation of satellite retrievals due to their specific overpass times has been presented. Chemical processes in the Jhb-Pta megacity were investigated by utilising an existing photochemical box model, i.e. MECCA-MCM. This model was further developed in this study and was termed the MECCA-MCM-UPWIND model. This model included horizontal and vertical mixing processes in the atmosphere. These processes were included to simulate the advection of upwind air masses into the modelling domain, as well as the entrainment from the troposphere resulting from the diurnal mixing layer (ML) height variation. Three processes, i.e. horizontal mixing, vertical mixing and ML height variation, were built into the MECCA-MCM- UPWIND model. The model was tested and evaluated to determine the efficiency of the model to represent atmospheric mixing processes. MECCA-MCM-UPWIND simulated horizontal mixing, vertical entrainment and ML height variations as expected. The input data for the model runs for the Jhb-Pta megacity modelling runs were either obtained from ground-based measurements or literature. Input data included meteorology, emission inventory, ML height and mixing ratios of the atmospheric chemical species. The chemical composition of the air mass entering the Jhb-Pta megacity was determined with MECCA-MCM- UPWIND. The concentrations and diurnal variability of criteria pollutant species were well predicted with the MECCA-MCM-UPWIND model. The day-time chemistry, especially, compared well, while slight under-predictions were observed for the night-time chemistry for most of the species. The differences observed between modelled and measured data could partially be ascribed to uncertainties associated with some of the input data obtained from literature used. The MECCA-MCM-UPWIND model was used to perform sensitivity studies on the influence of different parameters on O3 levels in the Jhb-Pta megacity. Possible scenarios to alter or mitigate pollution were also investigated. The results from the sensitivity analyses showed that O3 mixing ratios decreased within the Jhb-Pta megacity with increasing wind speeds. The contribution of local emissions to the change in the concentration of pollutants is reduced at higher wind speeds. It also indicated that the Mpumalanga Highveld can potentially be a source of NOx in the Jhb-Pta megacity that can lead to the titration of O3 . This also implies that if the air quality of the surrounding area improves, the concentration of the secondary pollutant O 3 will increase in the Jhb-Pta megacity due to the decrease in the titration of O3 . Sensitivity analyses also indicated that the Jhb-Pta megacity is a VOC-limited (or NOx-saturated) regime. Therefore, O3 reduction in the Jhb-Pta megacity will mostly be effective if VOC emissions are reduced. The same effect was observed in various cities world-wide where O3 increased when NOx emissions the Jhb-Pta megacity on the instantaneous production of O 3 was also investigated. A significant increase of approximately 23ppb O3 production was observed when changing from Euro-0 to Euro-3 vehicles with lower emissions of VOCs, NOx and CO. This compares with other modelled sensitivity studies of traffic emissions that also predict that future urban O 3 concentrations will increase in many cities by 2050 due to the reduction in the NOx titration of O3 despite the implementation of O3 control regulations<br>Thesis (PhD (Environmental Sciences))--North-West University, Potchefstroom Campus, 2013

The main aim of this project was to investigate the photochemical degradation pathways of lignin models using singlet oxygen and other photo-induced reactive species, in order to understand the photochemical transformations of the lignin polymer and other lignin-like polymers. The sensitized photolytic oxidation of lignin models containing the 13-0-4' lignin substructures using visible light, Rose Bengal and oxygen was studied in an attempt to understand and develop photocatalytic oxidation as a method for the conversion of lignin into added-value chemicals, Initial studies using a simple model dimer and attempting to replicate a published method[1] resulted in significant differences in the products when compared with the previous literature studies. A time study was carried out and a possible mechanism of a photo catalysed dimerization has been proposed. The observed radical coupling reaction has been shown to precede the eventual cleavage of a key benzylic ether bond in the tetramer and the formation of a quinone product and guaiacol by-product. Similar radical couplings were also observed for 13-5' dimer and trimer lignin models, Identification of the coupling products was obtained by spectroscopic characterization and corroborated by independent synthesis. Batch and flow reactors were tested and compared for the photolysis reactions. The flow reactor was proved to be more efficient than the batch reactor in terms of time-space conversion and yield. It was also shown that the flow reaction is a good method for the study of mechanism and optimization of the conditions required for the process, The dimerization process was then used for the preparation of three novel unsymmetrical coupling products. Successful cross-coupling of lignin models in this way provides a flexible new synthetic strategy for the preparation of more complex lignin models which is competitive with previous synthetic routes.

A Região Metropolitana de São Paulo (RMSP) enfrenta sérios problemas relacionados à degradação da qualidade do ar devido às emissões de sua intensa frota veicular, apresentando constantes ultrapassagens dos Padrões de Qualidade do Ar de poluentes como o ozônio (PQAr ~80ppbv). O Ozônio é formado na atmosfera em condições complexas em presença de intensa radiação solar, altas temperaturas, baixa umidade relativa, ventos fracos e altas concentrações dos precursores, óxidos de nitrogênio (NOx = NO + NO2) e compostos orgânicos voláteis (COVs). Assim, o problema da poluição do ar em centros urbanos precisa ser tratado com metodologias mais modernas para que possam ser estabelecidos novos critérios para redução de seus precursores e o conhecimento das condições mais adequadas (relação entre os COVs e os NOx, além da especiação destes COVs) para a redução do ozônio troposférico. Neste contexto, modelos fotoquímicos de qualidade do ar têm sido usados para auxiliar na tomada de decisões ambientais estratégicas. O módulo químico SAPRC Statewide Air Pollution Research Center é um mecanismo detalhado para simular reações entre COVs e NOX, desenvolvido para ser aplicado para atmosferas urbanas e regionais dos Estados Unidos. Porém, devido características específicas do combustível (aproximadamente 30% da frota usa etanol), no Brasil a poluição urbana apresenta características próprias. Dessa forma, baseado em campanhas anteriores de amostragem de COVs, no presente estudo foram modificados o inventário de emissões e o módulo químico (SAPRC99) do modelo fotoquímico CIT a fim de melhorar a representação do ozônio quanto a sua formação e consumo na atmosfera da RMSP. Para isso, alguns COVs como xilenos, 1-buteno e trimetilbenzenos foram explicitados. As simulações para os dias 30 e 31 de outubro de 2006 mostraram aumentos de espécies como peroxiacetilnitrato e ozônio de aproximadamente 10% para o centro de formação de pluma sobre a RMSP.<br>The Metropolitan Area of São Paulo (MASP) suffers severe problems related to air quality degradation presenting constant air quality standard overpasses for pollutants like ozone (QSAir ~80ppbv), due to its intense vehicular fleet. Ozone is formed in the atmosphere under complex conditions in the presence of strong solar radiation, high temperatures, low relative humidity, weak winds and also high precursor concentrations, such as nitrogen oxides (NOx = NO + NO2) and volatile organic compounds (VOCs). Therefore, the problem of air pollution in urban centers has to be treated using modern methodologies in order to establish new criteria for reduction of precursors and to know more adequate conditions (relation between VOCs and NOx, as well as speciation of these VOCs) in order to reduce tropospheric ozone. In this context, air quality photochemical models have been used to support strategic environmental decisions. SAPRC chemical mechanism Statewide Air Pollution Research Center developed to be applied in the United States urban atmospheres, consists of a detailed mechanism to simulate reactions between VOCs and NOx. However, due to specific fuel properties (about 30% of vehicular fleet uses ethanol), urban air pollution in Brazil presents its own characteristics, such as higher level of the oxygenated compounds. Hence, based on previous campaigns where VOCs had been sampled, the emission inventory and the chemical module (SAPRC99) were modified in order to improve ozone consumption and formation representation in the MASP atmosphere. As a result, some VOCs like xylenes, 1-butene and trimethilbenzens were explicated. Simulations for 30 and 31 of October 2006 presented increases in species formation like peroxyacetylnitrate and ozone about 10% in the centre of the MASP plume.

L’un des objectifs de cette thèse est d’interpréter les observations des principaux hydrocarbures(C2H2 et C2H6) effectuées par Cassini (NASA/ESA) sur Jupiter et Saturne. Les modèles photochimiques à une dimension sont insuffisants pour interpréter ces observations spatialement résolues. J’ai développé le premier modèle photochimique saisonnier à deux dimensions (altitude-latitude) des planètes géantes qui calcule leur composition chimique.En l’absence de transport méridional, la composition chimique de Saturne suit les variations d’ensoleillement. Les abondances de C2H2 et C2H6 mesurées par Cassini (Guerletet al., 2009) sont reproduites jusqu’aux latitudes moyennes, à des pressions supérieures à0,1mbar. Les écarts notés dans l’hémisphère sud suggèrent la présence de dynamique ou d’une chimie entre les ions et les espèces neutres. J’ai couplé, pour la première fois, mon modèle photochimique avec le modèle radiatif de Greathouse et al. (2008). Nous prédisons un décalage du pic saisonnier de température, par rapport aux précédents modèles, d’une demi-saison à haute altitude et aux hautes latitudes.Jupiter présente de faibles variations saisonnières de composition chimique, uniquement contrôlées par son excentricité. Les distributions méridionales observées de C2H2 etC2H6 présentent des tendances opposées (Nixon et al., 2010). Mon modèle est en accord avec les observations de C2H6 lorsque j’invoque une combinaison de diffusion méridionale et de circulation stratosphérique, tout en provoquant un plus grand désaccord avec les observations de C2H2. La chimie ionique pourrait principalement affecter C2H2 et jouer un rôle important dans l’atmosphère de Jupiter<br>One of the goals of this thesis is to interpret the observations of the main hydrocarbons(C2H2 and C2H6) from Cassini (NASA/ESA) on Jupiter and Saturn. The one-dimensional photochemical models are insufficient to explain these spatially resolved observations. I have developed the first two-dimensional (altitude-latitude) seasonal photochemical model for the giant planets, which predicts their chemical composition.Without meridional transport, Saturn’s chemical composition follows the insolation variations. The C2H2 and C2H6 abundances measured by Cassini (Guerlet et al., 2009)are reproduced from the equator up to mid-latitudes, at pressures higher than 0.1mbar.At higher latitudes, the disagreements suggest either a stratospheric circulation cell orthe signature of ion-neutral chemistry. For the first time, I have coupled our seasonal photochemical model with the seasonal radiative model of Greathouse et al. (2008). I predict that the seasonal temperature peak is shifted half a season earlier, with respect to previous models, at high latitudes in the higher stratosphere.Jupiter shows weak seasonal variations of chemical composition, only controlled by its orbital eccentricity. The observed meridional distributions of C2H2 and C2H6 show opposition trends (Nixon et al., 2010). C2H6 observed distribution is reproduced when Isuppose a combination of meridional diffusion and stratospheric circulation, while causingat the same time a stronger agreement with the C2H2 observations. Accounting for theion-neutral chemistry might preferentially affect C2H2 and potentially play a key role on hydrocarbon abundances in Jupiter’s stratosphere

La llegada de plantas exóticas fuera de su rango de distribución original y su posterior asentamiento en ecosistemas naturales no es una excepción en las Islas Baleares. En la actualidad tenemos 308 especies no nativas naturalizadas y subespontáneas que representan el 16% del total de la flora Balear. En esta tesis se ha evaluado el estado de la cuestión a nivel global y local. Se ha confeccionado el primer catálogo de flora introducida y se ha analizado cuales de ellas son más abundantes y peligrosas; así como también qué ecosistemas son más vulnerables a la introducción de éstas. También se ha profundizado en el conocimiento de dos de las especies exóticas más peligrosas en el litoral Balear: Carpobrotus edulis y C. affine acinaciformis. Se ha evaluado su influencia sobre la polinización, su tasa de crecimiento bajo diferentes escenarios ambientales, se ha confeccionado un modelo de crecimiento y se ha evaluado su impacto sobre la composición y estructura de las comunidades nativas.<br>L'arribada de plantes exòtiques fora del seu rang de distribució original i el seu posterior assentament a ecosistemes naturals no és una excepció a les Illes Balears. A l'actualitat tenim 308 espècies no natives naturalitzades i subespontànies que representen el 16% del total de la flora Balear. En aquesta tesi s'ha avaluat l'estat de la qüestió a nivell global i local. S'ha confeccionat el primer catàleg de flora introduïda i s'han analitzat quines d'elles són més abundants i perilloses; així com també quins ecosistemes són més vulnerables a la introducció d'aquestes. També s'ha profunditzat en el coneixement de dues de les espècies exòtiques més perilloses del litoral Balear: Carpobrotus edulis y C. affine acinaciformis. S'ha avaluat la seva influència damunt els vectors de pol·linització, la taxa de creixement a diferents escenaris ambiental, s'ha confeccionat un model de creixement, i s'ha avaluat el seu impacte damunt la composició i estructura de les comunitats natives.<br>The constant arrival of exotic plants into areas outside their original distribution range and further settlement in natural ecosystems is not an exception in the Spanish Balearic archipelago. At the moment we have 308 non native species (naturalized and casual), the 16% from the total Balearic flora. This thesis has evaluated the exotic plant problematic at global and local level. We have elaborated the first exotic plants list, its distribution and abundance, as well as its degree of impact on the more vulnerable environments. We went deeply into the knowledge of two very invasive plants along the coast of the Balearic islands: Carpobrotus edulis y C. affine acinaciformis. We have evaluated its influence over pollen transmission, its growth rate at different environmental conditions, we have too elaborated a non liner growth model and its impact on composition and structure in natural communities

Dans le cas de li(le plus reactif), identification de li(co)::(n), ou n = 1,2,3,4,(ou 6), avec des frequences de vibration de valence de co plus perturbees que pour les metaux de transition carbonyle,et de li::(m) co, ou m = 2,3, avec frequences nu (co) abaissees. Pour na et k, observation d'especes de haute stoechiometrie (c::(n)o::(n))**(2-) (m**(+))::(2) ou n = 2,3,4, formees apres irradiation uv-visible et correspondant a des transformations chimiques. Essai d'interpretation de ces differences de reactivite par une description quantique des agregats de plus basse stoechiometrie : dans le complexe 1 :1, les deux etats electroniques inferieurs sont l'etat **(2)sigma non liant et l'etat **(2)pi liant; la courbe de potentiel de lico possede un minimum pour li-c equiv. A 2,5 a au-dessous de la courbe de l'etat **(2)pi alors que pour naco, le minimum de la courbe pour l'etat **(2)pi est au-dessous de la courbe de l'etat **(2)sigma ; le calcul met en evidence le caractere ionique de m::(2)c::(2)o::(2) (acetylenediolate) resultant d'une reaction chimique

Les mesures ont ete faites, pres du sol, dans une region accidentee (4**(o)s-1**(o)e) de 1978 a 1984. L'aerosol est surtout constitue de composes du carbone, et sa distribution dimensionnelle est formee de 3 modes dont le plus important est centre vers 0,1 micron. Les variations et la composante submicronique sont interpretees en termes de formation et d'evolution des particules et de melanges dans l'atmosphere. Les plus petits noyaux sont formes a partir de gaz emis par la biosphere, principalement au cours de reactions photochimiques. Pendant les heures ensoleillees, la production totale est estimee a 1,8. 10**(5) cm**(-2). S**(-1). 70% des particules formees restent alors dans les vallees, mais sous le couvert forestier la production est faible, et les concentrations augmentent, en fin d'apres-midi, lorsque les melanges amenent les particules formees, le jour, en altitude

碩士<br>國立臺灣大學<br>環境工程研究所<br>84<br>The pollution of ozone in and downwind of large urban areas is getting serious with the development of the city. The production of ozone is in association with the emission of the precursor and the process of photochemical reaction. We cannot control the concentration of ozone only by reducing the emission of the precursor. In this research, we will find the relationship between the concentration of ozone, the emission of pollutant and the meteorological factor by air quality model. In this research, we develop a multi-layer photochemical trajectory model to simulate the condition of ozone pollution. We divide the air column into 10 layers, use the CBM IV chemical mechanism to solve the chemical part, and Crank- Nicolson numerical scheme to solve diffusion part. In this research, we find that we can back 10 hours to find the pollutant source, but we cannot treat the second day ozone pollution. In treating the first day ozone pollution, the performance of the model is good. In simulating the real case, the Tainan city may increase the concentration of ozone in the downwind area up to 180%.

A scaling-level model of a photochemical mechanism has been developed and integrated into an air quality model used to study ozone formation in an urban environment. A scaling analysis was used to capture the internal workings of a photochemical mechanism using the OZIPR trajectory model to simulate a smog chamber for a wide range of precursor concentrations and a variety of environmental conditions. The Buckingham P i method of dimensional analysis was used to express the relevant variables in terms of dimensionless groups. These grouping show maximum ozone, initial NOx and initial VOC concentrations to be made non-dimensional by the average NO₂ photolysis rate (j[sub av]) and the rate constant for the NO-O3 titration reaction ([sup k]NO); temperature by the NO-O₃ activation energy (E/R) and time by the cumulative NO₂ photolysis rate (J). The analysis shows dimensionless maximum ozone concentration can be described by a product of powers of dimensionless initial NOx concentration, dimensionless temperature (θ(T)) and a similarity curve (f) directly dependent on the ratio of initial VOC to NOx concentration (R) and internally dependent on the cumulative NO₂ photolysis rate: [Chemical Equation Diagram] When Weibull transformed, the dimensionless model output cluster onto two line segments. This is interpreted as-a break in ..the scaling and can be understood,in-terms of a change in governing feedback mechanisms separating low- and high-NOx chemistry regimes. The similarity relationship can be modeled by two Weibull distributions using four parameters: two describing the slopes of the line segments (01,02) and two giving the location of their intersection (β, λ): [Chemical Equation Diagram] A fifth parameter (γ) is used to normalize the model output. The most important parameter, β, the VOC to NOx ratio at the scaling break, defines a characteristic process scale for ozone photochemistry. The scaling analysis, similarity curve and parameterization appear to be independent of the details of the chemical mechanism, hold for a variety of VOC species and mixtures and are applicable over a wide range of VOC and NOx concentrations. The similarity relationship is used to generalize ozone-precursor relationships in terms of four rules governing ozone production (P(O₃)), to quantify NOx-inhibition and define isopleth slope. The scaling framework is used to study VOC reactivity, explore the scaling properties of a simple reaction mechanism and collapse a wide range of smog chamber measurements onto a single similarity curve. To complement the scaling analysis, a meteorological model and an emissions inventory were developed. These were incorporated into an air quality model used to explore the sensitivity of a regional ozone plume to environmental conditions, and precursor .concentrations. The air quality model consisted of a series of box models being advected by the mean wind, for a single day, where photochemistry of the precursors emissions was modeled using the similarity relationships developed from the scaling analysis. The chosen domain was the Lower Fraser Valley B.C., a complex coastal region that experiences moderate ozone episodes during summertime fair-weather conditions. Emission fields were developed using published emission totals, four land-use categories and generic temporal emissions curves and were found to be comparable with fields based on more detailed inventories. Wind observations (speed and direction), from 53 stations, on a typical episode day, were interpolated to produce hourly wind fields. Mixing depths were determined using a simple slab model incorporating the interpolated wind fields and measured heat fluxes. The most problematic aspect of the model was determining the effects of pollutant build up in the boundary layer, prior to the modeling day. This was handled by emitting precursors into the boundary layer and advecting them, without chemical reactions, until steady state concentrations were reached. These were dependent on the choice of background concentrations used to initialize the pre-conditioning scheme and were set so resulting boundary layer NOx and VOC concentrations were in agreement with the limited available data and peak ozone concentrations were typical of recent episodes. In departure from previous modeling studies, model validation was not through point by point analysis of model output and observations but through high level comparison of model sensitivity with a range of modeling techniques and observations. The model appears to capture ozone sensitivity to meteorological conditions and precursor concentrations; justifying its use as a screening tool. The model suggests: the region to be VOC limited; projected emissions reductions may not improve present episodic ozone concentrations; larger than anticipated reductions in NOx emissions, without equivalent additional VOC reductions, could increase episodic concentrations and future emissions reductions, stemming from TIER 2 LDV standards, which target NOx emissions to a greater extent than VOC emissions, may not result in appreciable changes in episodic ozone concentrations. These conclusions are intended to guide comprehensive modeling studies.<br>Science, Faculty of<br>Earth, Ocean and Atmospheric Sciences, Department of<br>Graduate

碩士<br>國立中央大學<br>太空科學研究所<br>106<br>To study the chemistry and composition of the upper atmosphere, we can utilize airglow emissions from the photochemical reactions of the ions in this region. When the atomic oxygen ions distributed in the ionospheric F region experience an energy level transition, visible light with a wavelength of 630.0 nm is released. We used the photometer system built by our team at NCU to perform ground-based observations of airglow over the sky of Taiwan at Lulin Observatory (23.46°N, 120.87°E) during selected night times. Ground-based airglow spectrometer observations throughout 2016 from the Institute of Solar-Terrestrial Physics (ISTP) in Irkutsk, Russia (51.8°N, 103.1°E) are also utilized. [22] We combined the mean values of our observations every 10 minutes with photochemical models based on the formulas derived from the theories of Link and Cogger (1988), Sobral et al. (1993), and Vladislav et al. (2008). With these different methods, we can estimate how the density of oxygen atomic ions varies with time and altitude and compare the results from empirical models with satellite-based observation data from FORMOSAT-3/COSMIC. The airglow brightness values simulated (Unit: volume emission rate) by the empirical GLOW model v0.98 by Solomon (2017) are also applied to validate the effectiveness of the three inversion models used in this research. The tendency and variation of the atomic oxygen ion density calculated by our photochemical models is compared to the ground-based time variation of airglow radiance, electron density observations of FORMOSAT-3/COSMIC, and input variables from GLOW. Similarities and differences are discussed. The pattern of atomic oxygen ion variation resolved by our inversion model will be utilized for further analysis of ionospheric composition variation in the future.

碩士<br>國立中興大學<br>環境工程學系所<br>106<br>According to rapid industrialization and urbanization, air quality monitoring is very important in Taiwan. Particulate matter is one of the main pollutants that exacerbate air quality. The pathway of ammonium nitrate is complex. The influencing factors include nitrogen conversion rate, daytime and nighttime formation mechanism, equilibrium constant of ammonium nitrate, and ammonia concentration. In this study, the formation rates of sulfate and nitrate are calculated based on CALPUFF model (Scire et al., 2000), and the outcomes of Gaussian Trajectory Model (GTx) simulation will be compared with the observations data. The result show, use photochemical module to simulated the concentration of pollutants are more close to the observations, and the correlation coefficients between calculated and observed concentrations are increased. This implies that photochemical module improved the performance of the model.

<p>A series of meso-phenyloctamethylporphyrins covalently bonded at the 4'phenyl position to quinones via rigid bicyclo[2.2.2]octane spacers were synthesized for the study of the dependence of electron transfer reaction rate on solvent, distance, temperature, and energy gap. A general and convergent synthesis was developed based on the condensation of <i>ac</i>-biladienes with masked quinonespacer-benzaldehydes. From picosecond fluorescence spectroscopy emission lifetimes were measured in seven solvents of varying polarity. Rate constants were determined to vary from 5.0 x 10⁹ sec^-1 in N,N-dimethylformamide to 1.15 x 10¹⁰ sec^-1 in benzene, and were observed to rise at most by about a factor of three with decreasing solvent polarity. Experiments at low temperature in 2-MTHF glass (77K) revealed fast, nearly temperature-independent electron transfer characterized by non-exponential fluorescence decays, in contrast to monophasic behavior in fluid solution at 298K. This example evidently represents the first photosynthetic model system not based on proteins to display nearly temperature-independent electron transfer at high temperatures (nuclear tunneling). Low temperatures appear to freeze out the rotational motion of the chromophores, and the observed nonexponential fluorescence decays may be explained as a result of electron transfer from an ensemble of rotational conformations. The nonexponentiality demonstrates the sensitivity of the electron transfer rate to the precise magnitude of the electronic matrix element, which supports the expectation that electron transfer is nonadiabatic in this system. The addition of a second bicyclooctane moiety (15 Å vs. 18 Å edge-to-edge between porphyrin and quinone) reduces the transfer rate by at least a factor of 500-1500. Porphyrinquinones with variously substituted quinones allowed an examination of the dependence of the electron transfer rate constant κ_ET on reaction driving force. The classical trend of increasing rate versus increasing exothermicity occurs from 0.7 eV ≤ |ΔG^0'(R)| ≤ 1.0 eV until a maximum is reached (κ_ET = 3 x 10⁸ sec^-1 rising to 1.15 x 10¹⁰ sec^-1 in acetonitrile). The rate remains insensitive to ΔG⁰ for ~ 300 mV from 1.0 eV ≤ |ΔG^0’(R)| ≤ 1.3 eV, and then slightly decreases in the most exothermic case studied (cyanoquinone, κ_ET = 5 x 10⁹ sec^-1).</p>

碩士<br>淡江大學<br>水資源及環境工程學系碩士班<br>93<br>It is well known that meteorological conditions are important input data for air quality models. Since Taiwan is an island with steep mountains, the air flows in Taiwan are significantly affected by local topography as well as surface parameters such as sea surface temperature and roughness. In general, it is a difficult task to collect accurate input data for a meteorological model. Hence, it is worth to investigate the effects of input data and computation algorithm of a meteorological model on the simulation results of a photochemical air quality model. The mesoscale meteorological model, RAMS, and photochemical air quality model, CAMx, was used in this study. Several runs were carried out by varying the parameters that control four-dimensional data assimilation (FDDA), topographic initialization methods, and sea surface temperature data. The effects of these modifications on the results of simulated meteorological fields, including the distributions of wind, temperature, and humidity, were studied. Then, the simulated meteorological fields were used as input of CAMx. Model. The performances of the CAMx model were evaluated by comparing the results with observations. The RAMS model employs Newtonian relaxation method for FDDA. While the analysis nudging is used, the nudging term will be controlled by a time scale parameter. Too strong nudging should be avoided, otherwise some circulations, such as land-sea breezes, mountain-valley winds, and topography effects will be diminished. For topographic initialization, the results obtained by the reflected envelop topography scheme are superior to that obtained by the conventional averaging approach. Two sea surface temperature data set were used, i.e., climatologically data and optimal interpolated real time data. The results of air quality simulation obtained by using two dataset are similar.

碩士<br>國立雲林科技大學<br>環境與安全衛生工程系碩士班<br>99<br>Recently, duo to the fast development in East Asia, emissions of pollutants have gradually increased and it will result in a serious air pollutant problem. Emission sources of pollutants affect air quality not only in local, but also in other regions by long-range transport. Therefore, the assessment of ozone pollution in Taiwan should consider pollutants not only from inside, but also from outside. With the increased emission in nearby countries, the control direction of ozone precursors may change in Taiwan, due to transboundary long-range transport. In order to clarify that, impact of the emission of air pollutants in East Asia on Taiwan&apos;&apos;s ozone air quality. This study utilized the Taiwan Air Quality Model (TAQM) to long-term simulate with four months. This study analysis that, impact of the emission in the status quo (2007s) and the future (2020s) in East Asia on the ozone concentration and the control direction of ozone pollution in Taiwan. The four periods of modeling are February, May, August, October, representing winter, spring, summer, autumn, respectively. Using Four months of the simulation results, represent the impact of transboundary transport to Taiwan in 2007s and 2020s. The study also discussed that, new emissions which Economic Zone in West of Taiwan Strait affect Taiwan&apos;&apos;s ozone concentration in May and October in the future (2020s) except the whole of East Asia. The impact of transboundary transport in 2007s on the average of daily peak ozone in Taiwan is 15.5 ppb, and the most serious case in 2020s increased by 3.7 ppb. If further calculated exposure days with ozone over 120 ppb, this is equivalent to ozone PSI≧100 days of station, the influence of transboundary transport in 2007 contribution to 72% of days of station in Taiwan, and increased by 47% in 2020s. Using H2O2/HNO3 as a photochemical indicator, analyze impact of transboundary transport on the control species of ozone pollution in Taiwan. The control species of ozone pollution in Taiwan in 2007s are primarily VOCs-limited. If emissions remain unchanged in Taiwan, but other countries continue to grow emissions in East Asia. The control species of ozone pollution in Taiwan in 2020s are still VOCs-limited. However, the increase is more in NOx-limited (26487 km2-d), and the increase is less in VOCs-limited (13770 km2-d). Further statistics change in control direction of ozone pollution for each grid in Taiwan from 2007s to 2020s. Move to the area of NOx-limited is 15% of the total pollution area, and move to the area of VOCs-limited is only 3%. This means that the future with other countries to increase their emissions, through the impact of transboundary transport, NOx control will more important in Taiwan. Future (2020s) Economic Zone in West of Taiwan Strait may be added emissions after completion of construction. Taiwan will increase 0.5 ppb on the average of daily peak ozone, and 3.2% on days of station. Although the effect is only 3.2%, this is only the new emissions of a single region from China (Fujian Province and its vicinity). Therefore, the effect of 3.2% is quite substantial.

The aqueous photochemistry of 4-hydroxy-3,5-dimethoxybenzoic acid (syringic acid) has been studied as a model humic substance in order to better understand the reactions that compounds of this type undergo in the natural environment. Syringic acid was chosen since it has been identified as a component of humic substances in the environment and bears many of chemical moieties found in structures of this type. In addition, there has been speculation that humic substances are responsible for some of the production of halomethanes that are released into the environment. Photolysis of these compounds in marine and estuarine waters may be responsible for the release of halomethanes which are known stratospheric ozone depleters. Photochemical product studies of syringic acid and related compounds along with UV-Vis spectrometry, laser flash photolysis and membrane introduction mass spectrometry were carried out in aqueous solutions to study its photochemical transformations. Syringic acid was found to form methanol at a 0.01 quantum yield upon its photolysis in basic solution. Other major photoproducts included 3-methoxygallic acid and 3,5-dimethoxybenzoic acid. Chloromethane was identified as a minor photoproduct in chloride enriched solution by following its production via membrane introduction mass spectrometry. The proposed mechanism for the formation of these photoproducts involves an initial photoprotonation of the benzene ring, resulting in a carbocation that can facilitate the nucleophilic attack by water or chloride, to produce methanol or chloromethane, respectively. The formation of 3,5-dimethoxybenzoic acid is via a novel pathway that involves the loss of the hydroxy group from the aromatic ring after the photoprotonation.

博士<br>淡江大學<br>水資源及環境工程學系博士班<br>97<br>It is well known that ozone episodes occur under weak synoptic conditions with low wind speed and strong sunlight. During these periods, the Land use/ Land cover (LULC) dataset and surface parameterization scheme have significant influence on the meteorological simulation. To improve the performances of numerical ozone forecast, a better representation of land surface in the meteorological model is needed. The aims of this study is to carried out a numerical study to investigate the influence of LULC data and surface parameterization on the results of meteorological simulation and the calculated spatial distributions of atmospheric pollutants during ozone episodes in Taiwan. An ozone episode occurred during the period June 4-6, 2003, was simulated using the RAMS and CAMx model. The town energy balance (TEB) urban canopy model was coupled to RAMS. Three numerical simulations were performed. The first simulation used AVHRR dataset and the TEB computation was turn off. The second simulation used MODIS dataset and the TEB computation was also turn off. The urban effects were represented by LEAF3 scheme for the first two runs. The third simulation used MODIS data and the TEB computation was turn on. The wind speeds computed by the first case were overestimated and the surface temperatures were underestimated when compared with the observations obtained from eight urban surface weather stations. In MODIS case, the surface wind speeds have better agreement when compared with observations. The results of surface temperature during day time were improved; however, they still underestimated during night time. As for the third case, the results for wind speeds and surface temperature were improved. Overall the meteorological simulations are superior when TEB is used. Numerical results indicate that urban can increases the surface temperature by 1~2 ℃ and decreases the wind speed by 1~2 m/s. The simulation indicates that the urban heat island effect is stronger at night than daytime. Urban can enhance the convection and atmospheric turbulence and increase mixing height. The results of three meteorological simulations were used to drive the air quality model. The calculated concentrations of air pollutants were evaluated against the observations obtained by Taiwan EPA air quality monitoring network. Most of the results are very reasonable and the simulation using TEB is superior to the other cases. The present study shows that both nocturnal and diurnal urban effects have an important impact on the temporal and spatial distributions of ozone and nitrogen dioxide. This study also examined the capability of applying RAMS-TEB-CAMx model to ozone forecasting during a 3-day episode of 29–31 May 2003. The results are fair when compared with observed O3 and NO2 concentrations. The performance of forecast in northern Taiwan is pretty good. However, the results of O3 concentrations were underestimated and NO2 concentrations were overestimated in middle and southern Taiwan. The large point sources located in the coastal zone will reduce the ozone concentration because of NOx titration effect. The peak ozone concentrations near the mountain range were underestimated. A possible reason of this imprecision is the error of wind direction caused by the complicated wind system in the simulation domain. Although the performance of this ozone forecast system is reasonable, there are numerous opportunities for improvements in the future.

A photochemical mechanism is a very important component of an air quality model, which simulates the change of pollutant concentrations due to chemical reactions in the air. The accuracy of model prediction is directly impacted by the photochemical mechanism. In this study, two state-of-the-science photochemical mechanisms, SAPRC07 and Master Chemical Mechanism (MCM) v3.1, were implemented in the Community Multi-scale Air Quality Model (CMAQ) version 4.6 developed by the US EPA to study a high ozone (O3) episode during the 2000 Texas Air Quality Study (TexAQS) from August 16, 2000 to September 7, 2000. Predicted O3 concentrations by S07C are lower than those of S99 with a maximum difference as high as 20 percent. The two mechanisms also show significant differences in the predicted OH, PAN, HCHO and HNO3 concentrations. Although the two mechanisms predict different ozone concentrations, the relative response factors (RRFs) of O3 at rural, urban and industrial sites under emission controls of anthropogenic NOx and VOC by factors 0.6 – 1.4 predicted by the two mechanisms are very similar. Predicted O3 concentrations by MCM are similar to those of SAPRC07. The MCM predicted total VOC OH reactivity is similar to the SAPRC07 predictions at a suburban site where biogenic emissions dominate the OH reactivity and is slightly lower than the SAPRC07 predictions at an industrial site where anthropogenic emissions dominate. Besides, the predicted 1-hr and 24-hr average concentrations of major O3 precursor VOCs by MCM show under predictions of alkanes and alkenes by a factor of 2-5, 6 for ethane and 8.5 for propane. Major aromatic compounds generally agree better with observations, although benzene is under-predicted by 80 percent. Species specific emission adjustment factors can be derived from these direct comparisons to improve emission inventories in future studies. At the Clinton Drive site, most of the under-predictions occur in the afternoon when industrial facilities are in the immediate upwind direction and the missing industrial emissions are likely evaporative sources whose emission rates are temperature dependent.

碩士<br>國立雲林科技大學<br>環境與安全工程系碩士班<br>95<br>Ozone (O3) and particulate matter (PM) are two main reasons causing air pollution in Taiwan. The air quality data monitored by Taiwan EPA (Environmental Protection Agency) shows the tendency of O3 keeps rising up. O3 as the representative of photochemical air pollution has become the major PSI (Pollutants Standards Index) for many monitoring sites. Limited by computer capability, short-term events are usually selected to simulate and assess air quality in the past, but the representative of entire air quality is more controversial. In recent years, because of the reinforcement of computer capability, it is become possible for long-term simulation of air quality. Long-term simulation not only solves the representative problems but also decrease the evaluation uncertainty resulted from short-term simulation. It was considered that there was no formal reference evaluating the effectiveness of regulatory policy improving the air quality by long-term simulation. In order to gain more believable simulated results offered to evaluate air quality improvement, this study will aim at the items above to proceeding the long-term simulation and subsequent analysis. The whole year of 2003 was selected to simulate air quality using Models-3/CMAQ associated with the meteorological data of MM5 provided by Taiwan air quality modeling center. The modeling results show that, from 2000 to 2011, if Taiwan emission is under natural growth, the spatial exposure (km2-hour) of ozone event (O3 > 120 ppb) could be worse up to about 98% compared to the base case. However, if emission reduction control strategy is enforced during the same period, it could improve 70% spatial exposure compared to the natural growth case. If future emission of large sources, which need to be permitted by EIA from 2000 to 2023, are all in operation, the spatial exposure (km2-hour) of ozone event (O3 > 120 ppb) could be worse about 0.7 times compared to the base case. The result reveals that the future emission either by nature growth or by large new sources can result to serious air quality problem. Therefore the control strategy of emission reduction will be important for air quality improvement and/or maintainance.

碩士<br>國立臺灣大學<br>環境工程學研究所<br>86<br>To improve ozone air quality, the benefit of reduction in volatile organic compounds (VOCs) according to ozone formation potential was better than to traditional mass control. Using the Taiwan Emission Data System (TEDS) in association with the Speciate database developed by the U.S. EPA, the ozone formation potential in Southern Taiwan was determined by the Maximum Incremental Reactivity (MIR) Scale of volatile organic compounds (VOCs). The results show that the major source of VOC emissions and ozone formation was biogenic emissions. With regards to ozone formation by pollution type, the VOC with the maximum ozone formation potential was ethylene in point source pollution, carbon monoxide in line source pollution, toluene in area source pollution, and ethylene in biogenic source pollution. Excepting the biogenic source, ethylene, toluene, and carbon monoxide accounted for 40.10﹪of total estimated ozone formation. The photochemical trajectory model was used to evaluate whether the MIR scale was applicable to Southern Taiwan. Reduction in ozone concentrations by completely eliminating ethylene, toluene, and carbon monoxide was not significant (<2.00﹪). Decreasing NOx emissions by 20﹪on the other hand, increased ozone reduction to over 60﹪. The MIR scale is more suitable for conditions where ozone formation is the most sensitive to VOC. According to the EKMA elimination model, ozone formation in Southern Taiwan is l

The present thesis reports about vibrational and quantum chemical investigations on model systems undergoing photochemical processes and pharmaceutically active compounds, respectively. Infrared (IR) and Raman spectroscopy were applied for the characterization of the ground state molecular structure. Moreover, resonance Raman (RR) spectra contain additional information about the resonantly enhanced excited state molecular structure. A quantitative resonance Raman intensity analysis in conjunction with the simultaneous simulation of the absorption spectra by means of time-dependent propagation methods was accomplished in order to extract valuable information about the excited state molecular structures of the investigated systems. Surface enhanced Raman scattering (SERS) allows one to determine the interaction and adsorption site of active agents on a metal substrate. Furthermore, density functional theory (DFT) and potential energy distribution (PED) calculations were carried out for an exact assignment of the vibrational spectra. Complete active space self consistent field (CASSCF) and configuration interaction (CI) calculations for some model systems were also performed to assess the experimental results on the excited state potential surfaces. The fundamentals of resonance Raman spectroscopy are treated in detail, describing the physical processes and emphasizing the theoretical methodologies which allow one to obtain the information about the resonantly excited state via an RR intensity analysis. The Brownian oscillator model to determine the solvent reorganization energy is briefly presented. Furthermore, the SERS enhancement mechanisms and selection rules to determine the orientation of the molecules adsorbed on the metal substrate are discussed. The Hartree-Fock approach to calculate the ground state geometry is expatiated, and the basic characteristics of the CI and CASSCF calculations are specified. The chapter ends with a short description of the DFT calculations. Chapter 4 deals with the investigation of the excited state intramolecular proton transfer of the model system, 1-hydroxy-2-acetonaphthone (HAN). The vibrations showing the highest displacement parameters correspond to stretching and in-plane deformation modes of the naphthalene ring and the conjugated carbonyl group, while the OH stretching mode exhibits no observable enhancement. The cooperative effect of the skeletal vibrations reduces the distance between the carbonyl and hydroxyl oxygen atoms in accordance with a general electron density redistribution. Hence, the leading force in the proton transfer process is the increase in electron density on the carbonyl group and the decrease of the negative charge on the hydroxyl oxygen. In chapter 5 the structural and vibrational characteristics of the organic mixed valence system N,N,N’,N’-tetraphenylphenylenediamine radical cation (1+) are discussed. The resonance Raman measurements showed that at least eight vibrational modes are strongly coupled to the optical charge transfer process in (1+). These Franck-Condon active modes were assigned to symmetric vibrations. The most enhanced band corresponds to the symmetric stretching mode along the N-phenylene-N unit and exhibits the largest vibrational reorganization energy. Nevertheless, symmetric stretching modes of the phenylene and phenyl units as well as deformation modes are also coupled to the electronic process. The total vibrational reorganization energy of these symmetrical modes is dominant, while the solvent induced broadening and reorganization energy are found to be small. Hence, (1+) adopts a symmetrical delocalized Robin-Day Class III structure in the ground state. Chapter 6 reports about a vibrational spectroscopic investigation of a model organic photorefractive thiophene derivative, 2-(N,N-diethylamino)-5-(2’,2’-dicyanovinyl)-thiophene. The geometry of the first excited state were optimized and the FC parameters were calculated using the configuration interaction with single excitations method. These calculations show that the contribution of the zwitterionic structure to the excited state is significantly higher than in the ground state. The resonance Raman spectra indicate that several stretching modes along the bonds connecting the donor and acceptor moieties as well as the S-C stretching vibrations are enhanced. Chapter 7 presents the vibrational analysis of an aziridinyl tripeptide, a cysteine protease inhibitor active drug. The vibrational analysis reveals stronger H-bonding of the aziridine NH unit in the solid state of the aziridinyl tripeptide than in the liquid electrophilic building block, indicating medium strong intermolecular H-bond interactions in the crystal unit. The amide hydrogen atoms of the aziridinyl tripeptide are involved in weaker H-bonds than in an epoxide analogon. Furthermore, the characteristic vibrational modes of the peptide backbone were discussed. Chapter 8 reports on the adsorption mechanism of two related anti-leukemia active agents, 6-mercaptopurine (6MP) and 6-mercaptopurine-ribose (6MPR) on a silver colloid. Both molecules adsorb through the N1 and possibly S atom on the metal surface under basic conditions. The SERS spectra recorded for acidic pH values showed that the ribose derivative exhibits a different adsorption behavior compared to the free base. 6MP probably adsorbs on the silver sol through the N9 and N3 atoms, while 6MPR interacts with the surface via the N7 and probably S atoms. Around critical biological concentrations and pH values i.e. at low concentrations and almost neutral condition (pH 7-9), 6MPR interacts with the substrate through both N7 and N1 atoms, possibly forming two differently adsorbed species, while for 6MP only the species adsorbed via N1 was evidenced<br>In der vorliegenden Arbeit wurden schwingungsspektroskopische und quanten-chemische Untersuchungen an unterschiedlichen Modellsystemen, die an photochemischen Prozessen beteiligt sind, und an verschiedenen Pharmazeutika durchgeführt. Die Methoden der Infrarot- (IR) und Raman-Spektroskopie wurden für die Charakterisierung der Grund-zustandsgeometrie verwendet. Darüber hinaus konnten aus Resonanz-Raman- (RR) Spektren zusätzliche Informationen über den elektronisch angeregten Zustand erhalten werden. Diese aufschlussreichen Aussagen über die elektronisch angeregten Zustände der untersuchten Systeme wurden durch die simultane quantitative Analyse der Resonanz-Raman-Spektren und des Absorptionsspektrums gewonnen. Die Anregungsprofile für die Resonanz-Raman-Streuung und die Absorptionsquerschnitte wurden mittels zeitabhängiger Propagationsmethoden berechnet. Oberflächen-verstärkte Raman-Streu- (SERS) Experimente ermöglichten die Charakterisierung der Wechselwirkungen und Adsorptionsbindungsstellen von Wirkstoffen an Metalloberflächen. Des Weiteren wurden Dichtefunktionaltheorie- (DFT) und PED-Rechnungen durchgeführt, um eine genaue Zuordnung der Schwingungsspektren zu gestatten. CASSCF- und CI-Rechnungen wurden in einzelnen Fällen durchgeführt, um sie mit den experimentellen Ergebnissen für die Potenzialhyperfläche des angeregten Zustands vergleichen zu können. Die Grundlagen der Resonanz-Raman-Spekroskopie wurden ausführlich diskutiert. Dabei wurden die physikalischen Prozesse beschrieben und die mathematischen Techniken, die die Bestimmung der Parameter des angeregten Zustands durch die RR-Intensitätsanalyse ermöglichen, hervorgehoben. Das Modell des Brownian-Oszillators für die Ermittlung der Lösungsmittel-Reorganisations-energie wurde kurz beschrieben. Weiterhin wurden die SERS Verstärkungsmechanismen und Auswahlregeln diskutiert. Der Hartree-Fock-Ansatz zur Berechnung des Grundzustandes sowie die CI- und CASSCF-Methoden wurde erläutert. Das Kapitel endete mit einer kurzen Beschreibung der Grundlagen von DFT-Rechnungen. Im vierten Kapitel wurden die Untersuchungen an einem Modell-Systems (1-hydroxy-2-acetonaphthone HAN), das einen Protonentransferprozess im angeregten Zustand zeigt, dargestellt. Die Streck- und Deformationsmoden des Naphthalinrings und der konjugierten Carbonylgruppe weisen die größten Displacement-Parameter auf, während die O-H-Streckschwingung keine Resonanz-Verstärkung erfährt. Diese Gerüst-schwingungsmoden verringern den Abstand zwischen den Carbonyl- und Hydroxyl-Sauerstoffatomen, was mit einer generellen Umverteilung der Elektronendichte einhergeht. Daher wird der Protonentransferprozess durch die Zunahme der Elektronendichte auf dem Carbonylsauerstoffatom und der gleichzeitigen Abnahme der negativen Ladung auf dem Hydroxylsauerstoffatom gesteuert. Im fünften Kapitel wurden die strukturellen und vibronischen Eigenschaften eines organischen gemischtvalenten Systems, des N,N,N’,N’-tetraphenylphenylenediamine Radikalkations (1+), untersucht. Die Resonanz-Raman-Experimente zeigten, dass mindestens acht Schwingungsmoden stark an den optischen Ladungstransferprozess gekoppelt sind. Diese Franck-Condon aktiven Moden wurden vornehmlich symmetrischen Moden zugeordnet. Die am meisten verstärkte Mode entspricht der symmetrischen Streckschwingung entlang der N-Ar-N-Achse. Jedoch sind auch symmetrische Streckschwingungsmoden der Phenyl- und Phyenylen-Gruppen und Deformationsmoden an dem elektronischen Prozess beteiligt. Der Beitrag dieser symmetrischen Moden zur Reorganisationsenergie dominiert, während die Lösungsmittelreorganisationsenergie nur sehr gering ist. Die erhaltenen Ergebnisse beweisen, dass es sich hier um ein symmetrisches delokalisiertes Robin-Day-Class-III-System handelt. Das sechste Kapitel beschäftigt sich mit einer schwingungsspektroskopischen Analyse eines photorefraktiven Thiophen-Derivat-Modellsystems, 2-(N,N-diethylamino)-5(2’,2’-dicyanovinyl)-thiophen. Die Geometrien des Grund- und ersten angeregten Zustands wurden optimiert und die FC Parameter unter Anwendung der CIS Methode berechnet. Diese Rechnungen ergaben, dass der Anteil der zwitterionischen Struktur im angeregten Zustand dominiert. Die Resonanz-Raman-Spektren zeigten, dass mehrere Streckschwingungsmoden entlang der Bindungen, die die Donor- und Akzeptor-Einheiten verknüpfen, und die S-C Streckschwingungsmoden verstärkt wurden. Das siebte Kapitel behandelt die Analyse eines Aziridinyl-Tripeptids, ein Wirkstoff gegen Cystein-Proteasen. Die Schwingungsanalyse ergab eine stärkere Wasserstoffbrückenbindung der Aziridin NH-Gruppe des Aziridinyl-Tripeptids im festen Zustand als in der flüssigen Baueinheit. Die Wasserstoffatome der Amidgruppen des Tripeptids sind an schwächeren Wasserstoffbrückenbindungen als die des Epoxid-Analogons beteiligt. Darüber hinaus wurden die charakteristischen Gerüstschwingungsmoden des Tripeptids diskutiert. Im vorletzten Kapitel wurde der Adsorptionsmechanismus von zwei Anti-Leukämie-Wirkstoffen, 6-Mercaptopurin (6MP) und 6-Mercaptopurin-ribose (6MPR) diskutiert. Unter basischen Bedingungen adsorbieren beide Moleküle über die N1- und S-Atome an der Metalloberfläche. Für biologisch kritischen Konzentrationen und pH-Werten, d.h. für nahezu neutrale Bedingungen (pH-Wert 7-9) und eine geringe Konzentration, wurde festgestellt, dass das 6MPR-Molekül mit dem Substrat sowohl über das N7- als auch N1-Atom wechselwirkt, wobei wahrscheinlich zwei unterschiedlich adsorbierte Spezies vorhanden sind. Im Gegensatz dazu weist das 6MP-Molekül nur eine über das N1-Atom adsorbierte Spezies auf

Les aérosols atmosphériques (par exemple les matières particulaires ou PM) sont une source majeure d’incertitude dans les modèles climatiques. Plusieurs études ont démontré que des concentrations élevées de PM réduisent l’espérance de vie. Les aérosols organiques secondaires (Secondary Organic Aerosols en anglais, SOA) sont formés dans l’atmosphère à partir des précurseurs gazeux à travers les réactions chimiques et les SOA représentent des composants majeurs de la masse des PM à l’échelle mondiale. Afin de mieux comprendre les processus chimiques responsables de la formation des SOA, un modèle en 0-D est élaboré pour simuler dynamiquement l’évolution des espèces organiques dans une parcelle d’air qui subit une oxydation photochimique produisant des SOA. Le modèle incorpore des paramètres récemment publiés pour la formation des SOA à partir des composés organiques volatiles (VOCs), ainsi que des composés organiques semi-volatiles et des composés organiques à volatilité intermédiaire (SVOCs et IVOCs). Le modèle est restreint par plusieurs mesures de précurseurs, incluant des mesures récemment développées qui fournissent des contraintes grandement améliorées sur les concentrations des précurseurs, et les prédictions sont comparées par rapport aux mesures des SOA prises au cours de la campagne CalNex. Lorsque les effets des pertes sur les parois des chambres à smog sont considérés pour les rendements des VOCs, la quantité et la vitesse de la formation des SOA dans le modèle sont plus en accord avec les observations. Les résultats de cette étude indiquent que les SVOCs et les IVOCs primaires sont responsables de la majorité (70 à 86 %) de la masse de SOA modélisée, accentuant leur grande contribution en tant que précurseurs des SOA. Cependant, la masse de SOA simulée est sous-estimée à des temps courts d’oxydation lorsque comparée aux données sur le terrain, mais à des temps plus longs, un accord modèle/mesures est observé. Cet écart peut être dû à un ΔIVOC/ΔCO ratio d’émission bas ou une sous-estimation basse des constantes d’oxydations des IVOCs, ce qui met en évidence la nécessité de poursuivre les études sur le terrain et dans les laboratoires de ces composés.<br>Atmospheric aerosols (i.e. particulate matter or PM) are a major source of uncertainty in climate models. Many studies have also shown that elevated concentrations of PM reduce life expectancies. Secondary organic aerosol (SOA) is formed in the atmosphere from gaseous precursors through chemical reactions and SOA represents a major component of PM mass globally. To better understand the chemical pathways responsible for SOA formation, a box model is designed to simulate dynamically the evolution of organic species in an air parcel as it undergoes photochemical oxidation producing SOA. The model incorporates recently published parameterizations for the formation of SOA from volatile organic compounds (VOCs), as well as from semi-volatile and intermediate-volatility organic compounds (SVOCs and IVOCs). The model is constrained by several measurements of precursors, including recently developed measurements that provide greatly improved constraints on precursor concentrations, and the predications are compared against measurements of SOA taken during the CalNex campaign. When accounting for the effect of chamber wall-losses on VOC yields, the amount and rate of SOA formation in the model is more consistent with observations. The results of this study also indicate that the primary SVOCs and IVOCs are responsible for a majority (70 – 86 %) of the model SOA mass, emphasizing their high contribution as SOA precursors. However, the SOA mass predicted is underestimated at shorter photochemical ages when compared to field measurements, but at longer ages, model/measurement agreement is observed. This bias may be due to low IVOC/CO emissions ratios or low estimated IVOC oxidation rate constants, which highlights the need for further field and laboratory studies of these compounds.

碩士<br>國立交通大學<br>應用化學系分子科學碩博士班<br>103<br>Stroke, which occurs as a result of deficiency in blood supply to the brain by occlusion (ischemic stroke) or bleeding (hemorrhagic stroke), is a leading cause of death. The use of animal models is an indispensable component for biomedical research and pharmaceutical development. With its well-characterized genome, high reproductive rate, translucency in the body and high conservation relative to human beings, the zebrafish has recently emerged as a popular model organism. In this research, I evaluate the feasibility to test thrombolytic agents using our zebrafish model of photochemical thrombosis. For zebrafish injected with tissue plasminogen activator (tPA), the blood clot became lysed gradually and the clot size decreased significantly. In contrast, the clot continued to grow in size for the control group that was not injected with tPA. I extended this photochemical approach to develop the zebrafish model of ischemic stroke. Through the control of laser exposure, partial or complete occlusion at selected cerebral blood vessels was induced reproducibly. Facilitated with a transgenic fish line that expresses green fluorescence protein in motor neurons, an infarction area near the occluded vessel was identified with decreased cellular fluorescence and positive stain of propidium iodide. I demonstrate also the application of multiphoton induced ablation to induce hemorrhagic stroke in zebrafish. Finally, I characterized the remodeling and altered hemodynamics of cerebral vasculature after ischemic and hemorrhagic stroke. We anticipate that our approach will facilitate not only fundamental research of stroke but also investigation of new therapeutic strategies.

碩士<br>國立交通大學<br>應用化學系分子科學碩博士班<br>101<br>According to World Health Organization (WHO), stroke is the primary cause of adult disability in developed countries and ranks only behind cardiac diseases as a cause of death. Stroke could lead to a rapid loss of brain function as a result of disturbance of the cerebral blood flow. Stroke can be caused by ischemia or hemorrhage; the former is caused by an interruption of the blood supply while the latter results from a rupture of blood vessels. A variety of animals such as rats or mice have been employed as model animals in the basic research of stroke. Common methods to induce stroke in the model animals include corrosion of blood vessels with FeCl3, ligation an artery by introducing a nylon intraluminal suture or applying an electrical current to the vessel. However, these methods suffer from drawbacks such as irreproducibility or complicated procedures of surgery. Recently, zebrafish (Danio rerio) has become a popular model organism of both fundamental and applied biomedical research. The zebrafish is a well-characterized vertebrate with a short cycle of reproduction, and transparent embryos and early larvae, hence allowing observation of blood circulation with light microscopy. In this study, I report a novel zebrafish model of stroke by photochemically induced thrombosis. I first established experimental parameters at the dorsal aorta of zebrafish larvae. To determine the intravascular concentration of photosensitizer in vivo, we developed a method based on fluorescence detection. We then determined the time to form thrombus at varied doses of photosensitizers. We demonstrated photochemically induced thrombosis in the dorsal aorta and showed the three-dimensional structure of thrombus labeled with fluorescent antibody of platelets and fibrins. We then applied this approach and successfully induced thrombosis in selected cerebral blood vessels of zebrafish larvae. We found that there was a drastic change in the hemodynamics, cardiac function, and swimming behaviors. We also observed rerouting of some cerebral vessels and neovasculature after stroke in zebrafish. The phenomena conform to the characteristics of human stroke. To our knowledge, this is the first demonstration of photochemically induced thrombosis and stroke in zebrafish larvae. In contrast to conventional method, our approach does not require complicated procedures of surgery. We anticipate that this new stroke animal model might not only facilitate development of therapeutic interventions against stroke but also improve our understanding of the pathophysiology of stroke.

Yes<br>The peripheral nervous system has a limited innate capacity for self-repair following injury, and surgical intervention is often required. For injuries greater than a few millimeters autografting is standard practice although it is associated with donor site morbidity and is limited in its availability. Because of this, nerve guidance conduits (NGCs) can be viewed as an advantageous alternative, but currently have limited efficacy for short and large injury gaps in comparison to autograft. Current commercially available NGC designs rely on existing regulatory approved materials and traditional production methods, limiting improvement of their design. The aim of this study was to establish a novel method for NGC manufacture using a custom built laser-based microstereolithography (muSL) setup that incorporated a 405 nm laser source to produce 3D constructs with approximately 50 mum resolution from a photocurable poly(ethylene glycol) resin. These were evaluated by SEM, in vitro neuronal, Schwann and dorsal root ganglion culture and in vivo using a thy-1-YFP-H mouse common fibular nerve injury model. NGCs with dimensions of 1 mm internal diameter x 5 mm length with a wall thickness of 250 mum were fabricated and capable of supporting re-innervation across a 3 mm injury gap after 21 days, with results close to that of an autograft control. The study provides a technology platform for the rapid microfabrication of biocompatible materials, a novel method for in vivo evaluation, and a benchmark for future development in more advanced NGC designs, biodegradable and larger device sizes, and longer-term implantation studies.