Ozone generation by wire-to-cylinder corona reactor with N2+O2 mixture

The UV-visible spectroscopyin the range from190 to 320 nm wasutilizedtodetectthe ozone formation, in wire-to-cylindercorona reactorwithnegativepolarity. The effectof N2+O2 mixture on ozone production has been investigated. The maximum production of ozone was already corresponding to 70% of oxygen in the gas mixture forany applied voltage from 4,5 to 7 K

Experimental study of positive corona discharge in mixtures of CO2 and N2

Positive corona discharge in mixtures of CO2 and N2 has been experimentally investigated using a coaxial wire-to-cylinder corona discharge reactor. Special attention has been paid to the stability of the corona current and to the generation of ozone and nitrogen oxides in time, which are influenced by the applied voltage and the ratio of CO2:N2 in the gas mixture

Ozone production by corona discharge using a hollow needle-plate electrode system

Ozone generation using a hollow needle-to-plate corona reactor has been investigated using both positive and negative polarities and various flow rates. Oxygen could be introduced in the reactor either through the needle electrode or through a port on the lateral wall. This configuration al-lowed studying the effect of the flow direction on ozone production

Experimental study of dielectric barrier discharge in mixtures of carbon dioxide and oxygen

Carbon dioxide decomposition in mixtures of CO2and O2has been experimentally investigatedusing dielectric barrier discharge, with special interest on O3and COproductions. Experiments have been conducted at different frequencies and operating voltages, and the concentration of O3and COhave been measured by means of absorption spectroscopy in the UV and in the IR regions. According to the observations, theproductionof both speciescan be substantially increased by adding molecular oxygento carbon dioxide, even in small proportion

Negative corona discharge in mixtures of CO2 and N2: modeling and experiments

The decomposition of CO2 by the effect of negative corona discharge has been experimentally and numerically investigated for different admixtures of N2. The chemical kinetics model used in the simulation includes a wide variety of reactions between electrons, ions, atoms and molecules, such as ionization and recombination, electron+impact dissociation, dissociative recombination, dissociative attachment, thermal reactions between neutral chemical species, etc. Using the current+voltage characteristic as input data, the radial distributions of charged and neutral species has been predicted for different applied voltages and gas compositions. The generation of ozone, carbon monoxide and nitrogen oxides during the application of the corona discharge has been measured using ultraviolet and FTIR spectrophotometr

Ozone generation in a wire-to-cylinder corona discharge ozonizer fed with mixtures of O2 and N2

The generation of ozone in a coaxial wire-cylinder corona discharge reactor has been experimentally investigated using variable proportions (5% to 90%) of oxygen in nitrogen. The experiments have been carried out under negative polarity and using different gas flow rates (50 cm3/min to 200 cm3/min). The obtained results show that the corona current exhibits a certain dependence with the percentage of oxygen in the gas mixture, which may influence the rate of ozone production. Moreover, the evaluation of the ozone yield has revealed a non-linear dependence of this magnitude with the concentration of oxygen. The maximum ozone yield was obtained when the percentage of oxygen in the gas mixture was about 70%

The Use of a Scenario-Based Nominal Group Technique to Assess P/CVE Programs: Development and Pilot Testing of a Toolkit

Preventing and countering violent extremism (P/CVE) requires coordination among multiple agencies, stakeholders and systems. The complexity of this task (compounded by the variety of P/CVE programming around the world) creates a  challenge for those hoping to develop these initiatives. The purpose of this project was to develop a replicable process and corresponding toolkit to engage multiple stakeholders in consensus building around the efficacy and improvement of nascent, developing or mature systems-level P/CVE programs. As a method, we adapted the process of nominal group technique (NGT), a structured-brainstorming tool that provides an orderly procedure for obtaining qualitative and ranked information from heterogenous participant pools. The technique we developed is based on a case-study approach (“scenario”) which we then tested in three countries (USA, Sweden, and North Macedonia) with existing P/CVE initiatives at different stages of development. We conducted scenario-based NGT sessions in each location and then systematically analyzed the results using iterative qualitative coding based on a common framework. Results were analyzed to achieve consensus on the most common system-level challenges and system-level functions, necessary to overcome those challenges, in each location. Practitioners in each local jurisdiction were then able to utilize the results derived from the NGT for their own purposes, such as advocacy to policy makers, strategic regional P/CVE planning, and ongoing stakeholder engagement. Acknowledgments: This project was funded by the NATO Science for Peace and Security Programme under the award entitled "Evaluation Support for CVE at the Local Level" SPS.MYPG5556, the Swedish Contingency Agency (MSB), and the U.S. Department of Homeland Security (DHS), Science and Technology Directorate (Cooperative Agreement Number: 2015-ST-108-FRG005). The content of this manuscript as well as the views and discussions expressed are solely those of the authors and do not necessarily represent the official views of any of the above institutions, nor does mention of trade names, commercial practices, or organizations imply endorsement by the U.S. government

Chern-Simons Invariants of Torus Links

We compute the vacuum expectation values of torus knot operators in Chern-Simons theory, and we obtain explicit formulae for all classical gauge groups and for arbitrary representations. We reproduce a known formula for the HOMFLY invariants of torus links and we obtain an analogous formula for Kauffman invariants. We also derive a formula for cable knots. We use our results to test a recently proposed conjecture that relates HOMFLY and Kauffman invariants.Comment: 20 pages, 5 figures; v2: minor changes, version submitted to AHP. The final publication is available at http://www.springerlink.com/content/a2614232873l76h6