Materials Design for High-Performance Organic Redox Flow Batteries and Electrocatalytic Carbon Dioxide and Nitrogen Reduction

Nowadays, the utilization of renewable energy resources such as solar and wind energy has been realized to be a sustainable and environmentally benign strategy to alleviate the world’s severe dependency on traditional fossil fuels, and thus enables the environmental recovery and sustainable development of the economy. The massive commercialization of solar and wind energy raises the demands for advanced energy storage technologies, among which the redox flow battery has been recognized as a promising solution due to it is low cost, safe, environmentally benign, and easy to be scaled up. All vanadium redox flow battery stands for the most important system in the market. However, the high price of raw material (V2O5), active materials crossover leaded self-discharge, and hazardous electrolyte limit its broad application. Therefore, it is urgent to explore new active materials that are cheaper, more stable and more sustainable. Redox active organic molecules are great candidates to meet those requirements. The metal-free molecules are normally composed of elements of C, H, O, N,etc., which have massive resources from nature. With the rational molecular design, the organic molecules could be very tolerant of side reactions and chemical decomposition. Their electrochemical and physicochemical properties (such as redox potential, solubility and so on) can also be tuned by molecular engineering. My efforts have been putting on design highly water-soluble and stable ferrocene derivative and other metal-free molecules, for example, viologen, (2,2,6,6-Tetramethylpiperidin-1-yl)oxyl (TEMPO), and anthraquinone derivatives. Their electrochemical properties and battery performance were evaluated with comprehensive techniques. Besides, we systematically studied the chemical decomposition mechanism of these active materials by UV-Vis monitoring, NMR characterization, and half-cell long term cycling. Elucidating the active material decomposition mechanism helps us to improve the molecular structure design for more stable organic redox active materials developing in the future. Electrocatalysis is a process where electrochemical reactions happen on the surface of the electrodes which deliver or accept electrons. Electrocatalysis could provide another solution for valuable product synthesis with environment protection especially when it is integrated with renewable energy. I have been focusing on electrocatalytic CO2 and N2 fixation to synthesis carbohydrate and ammonia in aqueous media. Using CO2 and water as the reactant, nitrogenase as the catalyst, we electrochemically synthesized formate with high efficiency. I also carefully examined the catalytic activity of Mo2N for nitrogen reduction reaction (NRR). 15N2 isotope labeling experiment revealed that instead of catalytic N2 reduction, the ammonia formation is from nitride decomposition. The present results raise an urgent alert to the application of other metal nitrides or even nitrogen contained materials for electrocatalytic N2 reduction reactions

Empowering Citizens in the Digital Age : a systematic evaluation of voting advice : applications and best practices for their design

Voting Advice Applications (VAAs) are online tools that match voters and parties based on common positions on a series of issues. Starting as tools for political education, VAAs have nowadays become relevant political actors. Besides providing information, they also raise electoral turnout, improve political knowledge and influence party choice. The degree in which they do so depends on their design. In this thesis, I view the design of VAAs as a process and focus on two steps: the questionnaire and the visualizations. For the questionnaire I focus on two aspects: the scales used to position users on the political map and the formulation of the questions. I assess the scales using various data-reduction techniques and rank them on unidimensionality, quality and reliability. I find that most scales score insufficient, though the score depends on the construction method used for the scale. The cause of these problematic scales is that VAA users often apply simplification methods. This means they do not always understand the question or use the response categories as intended. This results in problematic scales, resulting in a political map that is difficult to interpret. Also, I find that altering the questions in the main questionnaire to have either a positive or negative formulation, not only influences the responses of the users but the match between the user and the party as well. For the visualization, I run an online experiment in which I ask users to answer questions related to various kinds of visualization. I find that not only do they have difficulty to finish some basic tasks, they also have diverging interpretations of popular VAA visualizations. My main conclusion is therefore that the design of VAAs cannot be neutral. Also, the underlying information used to calculate the match and visualize the political map are often troublesome. Yet, I also show designers can use simple methods to improve their VAAs. This is important as VAAs are likely to become even more popular than they are already at this moment

The Role of CSR in Promoting Energy-Specific Pro-Environmental Behavior among Hotel Employees

Mitigating environmental crises requires efforts to reduce carbon emission at every level and segment of an economy. In this respect, the energy sector is blamed for increasing greenhouse gas emissions (GHG) throughout the globe. Specifically, it was specified that electrical energy contributes to 35% of the world’s GHG emissions. Without a doubt, the topics related to clean and green energies remained a part of academic discussion; however, a critical knowledge gap exists in most studies. That is, most of the prior literature focused only on the production side (supply side) of electrical energy, neglecting the consumption side (consumption at the level of individuals). Given that a significant amount of electricity has been consumed by the individuals in buildings (homes, offices, or others) for heating and cooling purposes, it is important to promote a target-specific (energy-specific) pro-environmental behavior (TSPEB) of individuals. However, such a debate did not receive any significant attention previously. Further, psychological factors such as employees’ environmental commitment (EEC) and green self-efficacy (GSE) were identified as critical mediators to drive different employees’ outcomes, but the mediating effect of EEC and GSE was not tested earlier to foster TSPEB in a CSR framework. The data for the current work were collected from employees of different hotels in a developing country by employing a survey strategy (n = 383). The structural equation modeling was used to analyze the data, which confirmed that hospitality employees’ CSR perceptions could improve TSPEB. The statistical results also confirmed the significant mediating effects of EEC and GSE. The finding of this study will help the hospitality sector to improve its efforts for de-carbonization by improving the energy consumption behavior of employees as an outcome of CSR

The Role of CSR in Promoting Energy-Specific Pro-Environmental Behavior among Hotel Employees

Mitigating environmental crises requires efforts to reduce carbon emission at every level and segment of an economy. In this respect, the energy sector is blamed for increasing greenhouse gas emissions (GHG) throughout the globe. Specifically, it was specified that electrical energy contributes to 35% of the world’s GHG emissions. Without a doubt, the topics related to clean and green energies remained a part of academic discussion; however, a critical knowledge gap exists in most studies. That is, most of the prior literature focused only on the production side (supply side) of electrical energy, neglecting the consumption side (consumption at the level of individuals). Given that a significant amount of electricity has been consumed by the individuals in buildings (homes, offices, or others) for heating and cooling purposes, it is important to promote a target-specific (energy-specific) pro-environmental behavior (TSPEB) of individuals. However, such a debate did not receive any significant attention previously. Further, psychological factors such as employees’ environmental commitment (EEC) and green self-efficacy (GSE) were identified as critical mediators to drive different employees’ outcomes, but the mediating effect of EEC and GSE was not tested earlier to foster TSPEB in a CSR framework. The data for the current work were collected from employees of different hotels in a developing country by employing a survey strategy (n = 383). The structural equation modeling was used to analyze the data, which confirmed that hospitality employees’ CSR perceptions could improve TSPEB. The statistical results also confirmed the significant mediating effects of EEC and GSE. The finding of this study will help the hospitality sector to improve its efforts for de-carbonization by improving the energy consumption behavior of employees as an outcome of CSR

Parametric analysis of microwave and laser systems for communication and tracking. Volume 3 - Reference data for advanced space communication and tracking systems

Reference data for advanced microwave and laser communication and tracking systems - Vol.

The critical analysis of scenario construction in the Polish foresight initiatives

The aim of the article is to present the diagnosis of scenario method application in the Polish foresight initiatives. The concept of scenario method, its evolution, the state of the art of the Polish foresight studies and the critical analysis of the application of this method have been presented. From the questionnaire results the authors have identified (i) the approach used in scenario construction, (ii) the most important phases of scenario construction, (iii) the interconnection of scenario method with other methods of scenario construction, (iv) the profile of experts involved in foresight projects, (v) the profile of experts involved in scenario construction, (vi) the application of the triangulation principle in scenario construction, (vii) the application of wild cards in scenario construction and techniques to identify them, (viii) the average time of scenario construction process, (ix) the linkage of scenarios to other documents, (x) the number of scenarios elaborated upon, and (xi) the main difficulties in the process of scenario construction. To achieve article aims there have been used the following research methods: a literature review, the method of critical analysis and logical construction, survey research, the status of Polish foresight projects, interim and final report analysis. The research has been funded by the National Science Centre in Poland within a research project entitled Scenarios in future shaping and anticipation for foresight studies, project number: 4194/B/H03/2011/40

Sketchmate: A Computer-Aided Sketching and Simulation Tool for Teaching Graph Algorithms

In this dissertation, we developed and tested a sketching, visualization, and simulation tool called Sketchmate for demonstrating graph algorithms commonly taught in undergraduate computer science courses. For this research, we chose to focus on shortest path and network flow algorithms. Two versions of this tool have been implemented: 1) an instructor tool that supports computer-aided manual simulations of algorithms that augment traditional whiteboard presentations, allowing lectures to be more dynamic and interactive, and 2) a student tool that supports computer-aided manual practice of algorithms that enables students to work through homework problems more quickly while providing detailed incremental feedback about their performance and about how to solve a problem when they get stuck. Previous algorithm simulation systems have essentially forced instructors to narrate an algorithm as though they were describing an automated set of slides. In contrast, our tool allows instructors to manually manipulate attributes of a graph as they demonstrate an algorithm. A set of experiments was conducted using the tools. The results for the student tool showed that there was no statistically significant difference in test score improvement between Sketchmate and paper and pencil students, although they did show that Sketchmate students scored roughly one letter grade higher than paper and pencil students. Based on survey data, the students preferred using the tool to using paper and pencil. The results of the experiment involving the instructor tool showed that although there was no statistically significant difference in learning between Sketchmate and the whiteboard, both the instructor and the students preferred a Sketchmate lecture to a whiteboard lecture