Emissions inventories significantly affect photochemical air quality model performance and the development of effective control strategies. However, there have been very few studies to evaluate their accuracy. Here, to evaluate a volatile organic compound (VOC) emissions inventory, we implemented a combined approach: comparing the ratios of carbon bond (CB)-IV VOC groups to nitrogen oxides (NOx...

The reduction of nitrogen oxides (NOx) emissions from an existing burner is a a challenging task requiring the understanding of interactions between burner geometry and flame aerodynamics. Currently, three approaches for NOx control exist: fuel or flue gas treatment and combustion modifications. Low NOx burner design is economically attractive for natural gas and light fuel oil combustion since...

OpenFlow assumes a logically centralized controller, which ideally can be physically distributed. However, current deployments rely on a single controller which has major drawbacks including lack of scalability. We present HyperFlow, a distributed event-based control plane for OpenFlow. HyperFlow is logically centralized but physically distributed: it provides scalability while keeping the bene...

Forty light-duty gasoline vehicles (LDGVs), ninety two diesel trucks (DTs), and twenty rural vehicles (RVs) were measured in Beijing, Xi’an, and Shenzhen in China using a portable emissions measurement system (PEMS). We obtained gaseous emission factors (EFs) for LDGVs of different emission control technologies (including Euro 0, Euro I, Euro II, Euro III and Euro IV), and EFs of fine particula...

Ozone is produced by chemical interactions involving nitrogen oxides (NOx) and volatile organic compounds in the presence of sunlight. At high concentrations, ground-level ozone has been shown to be harmful to human health and to the environment. It has been recognized that ozone is a regional-scale problem and that regionwide control strategies would be needed to improve ozone air quality in t...

We recently showed elevated reactive oxygen species (ROS), reduced urinary excretion of NO metabolites (NOx), and increased NO sequestration as nitrotyrosine in various tissues in rats with lead-induced hypertension. This study was designed to discern whether the reduction in urinary NOx in lead-induced hypertension is, in part, due to depressed NO synthase (NOS) expression. Male Sprague-Dawley...

Control of aftertreatment systems for lean burn technology engines represents a big challenge, due to the lack of on-board emission measurements and the sensitivity of the hardware components to ageing and sulphur poisoning. In this paper, we consider the control and adaptation of aftertreatment systems involving lean NOx trap (LNT). A phenomenological LNT model is presented to facilitate the m...

The oxygen isotope composition of nitrogen oxides (NOx) in the atmosphere is a useful tool for understanding the oxidation of NOx into nitric acid / nitrate in the atmosphere. A set of experiments was conducted to examine change in isotopic composition of NOx due to NOx–O2– O3 photochemical cycling. At low NOx / O2 mixing ratios, NOx became progressively and nearly equally enriched in 17O and 1...

As the regulations of pollutant emission is getting more and more strict, models of pollutant formation, as a part of system level models for control design, are needed. In this thesis NOx (nitrogen oxides) formation is modeled. A method is developed to mix equilibrium and non-equilibrium reaction equations to model NOx formation in combustion processes. This algorithm reduces high-index DAE sy...