The 1991 International Aerospace and Ground Conference on Lightning and Static Electricity, volume 2

The proceedings of the conference are reported. The conference focussed on lightning protection, detection, and forecasting. The conference was divided into 26 sessions based on research in lightning, static electricity, modeling, and mapping. These sessions spanned the spectrum from basic science to engineering, concentrating on lightning prediction and detection and on safety for ground facilities, aircraft, and aerospace vehicles

Catalytic strategies for enhancing electrochemical oxidation of 1,4-dioxane: TiO2 dark activation and microbial stimulation

Includes bibliographical references.2016 Summer.1,4-dioxane, a probable human carcinogen, is an emerging contaminant currently being reviewed by the U.S. Environmental Protection Agency for possible health-based maximum contaminant level regulations. As both stabilizer in commonly used chlorinated solvents and as a widely used solvent in the production of many pharmaceuticals, personal care products, (PPCPs), 1,4-dioxane has been detected in surface water, groundwater and wastewater around the U.S. It is resistant to many of the traditional water treatment technologies such as sorption to activated carbon, air stripping, filtering and anaerobic biodegradation making 1,4-dioxane removal difficult and/or expensive. State-of-the art technologies for the removal of 1,4-dioxane usually apply advanced oxidation processes (AOPs) using strong oxidants in combination with UV-light and sometimes titanium dioxide (TiO2) catalyzed photolysis. These approaches require the use of expensive chemical reagents and are limited to ex situ (i.e. pump and treat) applications. Here, at Colorado State University’s Center for Contaminant Hydrology, innovative flow-through electrolytic reactors have been developed for treating groundwater contaminated with organic pollutants. The research presented in this dissertation has investigated catalytic strategies for enhancing electrochemical oxidation of 1,4-dioxane in flow-through reactors. Two types (abiotic and biotic) of catalysis were also explored: (1) dark, electrolytic activation of insulated, inter-electrode TiO2 pellets to catalyze the degradation of organic pollutants in the bulk solution by reactive oxygen species (ROS), and (2) adding permeable electrodes upstream of dioxane-degrading microbes, Pseudonocardia dioxanivorans CB1190, to pre-treat mixed contaminant water and provide O2 stimulation to these aerobic bacteria. For the abiotic form of catalysis, we characterized the properties of novel TiO2 inter-electrode material, and elucidated the properties most important to its catalytic activity, using 1,4-dioxane as the model contaminant. The TiO2 was novel in its use as an “inter-electrode” catalyst (not coated on the electrode and not used as a TiO2 slurry) and in the mechanism of its catalytic activation occurring in dark (not photocatalysis) and insulated (not typical electrocatalysis) conditions. Further studies were performed using electrochemical batch reactors and probe molecules in order to gain mechanistic insights into dark catalysis provided by detached TiO2 pellets in an electrochemical system. The results of our investigations show that electrolytic treatment, when used in combination with this catalytically active inter-electrode material, can successfully and efficiently degrade 1,4-dioxane. Benefits of catalyzed electrolysis as a green remediation technology are that (1) it does not require addition of chemicals during treatment, (2) it has low energy requirements that can be met through the use of solar photovoltaic modules, and (3) it is very versatile in that it could be applied in situ for contaminated groundwater sites or installed in-line on above-ground reactors to remediate contaminated groundwater. Although, 1,4-dioxane appears to be resistant to natural attenuation via anaerobic biodegradation, some aerobic bacteria have been shown to metabolize and co-metabolize 1,4-dioxane. For example, growth-supporting aerobic metabolism/degradation of 1,4-dioxane by Pseudonocardia dioxanivorans CB1190, has been demonstrated in laboratory studies. However, previous studies showed that this biodegradation process is inhibited by the presence of chlorinated solvents such as 1,1,1-trichlorethane (1,1,1-TCA) and trichloroethene (TCE). This could dramatically impact the success for in situ 1,4-dioxane biodegradation with P. dioxanivorans since chlorinated solvents are common co-contaminants of 1,4-dioxane. Our previous investigations into electrolytic treatment of organic pollutants both ex and in situ showed that effective degradation of chlorinated solvents like TCE was achievable. In addition, the electrolysis of water generates molecular O2 required by the CB1190 bacteria as well. This led us to hypothesize that the generation of O2 could enhance aerobic biodegradation processes, and the concurrent degradation of co-solvents could reduce their inhibitory impact on 1,4-dioxane biodegradation. In flow-through sand column studies presented here, we investigate the electrolytic stimulation of Pseudonocardia dioxanivorans CB1190, with the expectation that anodic O2 generation would enhance aerobic biodegradation processes, and concurrent degradation of TCE would reduce the expected inhibitory impact on 1,4-dioxane biodegradation. Results show that when both electrolytic and biotic processes are combined, oxidation rates of 1,4-dioxane substantially increased suggesting that aerobic biodegradation processes had been successfully stimulated. In summary, the results of this dissertation provide evidence of (1) efficient removal of recalcitrant 1,4-dioxane, especially with the addition of inter-electrode TiO2 catalysts, (2) elucidate possible mechanistic pathways for electro-activated dark TiO2 catalysis, and (3) provide evidence for successful synergistic performance for electro-bioremediation treatment during simulated mixed, contaminant plume conditions

The Road to Next-Generation Multiple Access: A 50-Year Tutorial Review

The evolution of wireless communications has been significantly influenced by remarkable advancements in multiple access (MA) technologies over the past five decades, shaping the landscape of modern connectivity. Within this context, a comprehensive tutorial review is presented, focusing on representative MA techniques developed over the past 50 years. The following areas are explored: i) The foundational principles and information-theoretic capacity limits of power-domain non-orthogonal multiple access (NOMA) are characterized, along with its extension to multiple-input multiple-output (MIMO)-NOMA. ii) Several MA transmission schemes exploiting the spatial domain are investigated, encompassing both conventional space-division multiple access (SDMA)/MIMO-NOMA systems and near-field MA systems utilizing spherical-wave propagation models. iii) The application of NOMA to integrated sensing and communications (ISAC) systems is studied. This includes an introduction to typical NOMA-based downlink/uplink ISAC frameworks, followed by an evaluation of their performance limits using a mutual information (MI)-based analytical framework. iv) Major issues and research opportunities associated with the integration of MA with other emerging technologies are identified to facilitate MA in next-generation networks, i.e., next-generation multiple access (NGMA). Throughout the paper, promising directions are highlighted to inspire future research endeavors in the realm of MA and NGMA.Comment: 43 pages, 38 figures; Submitted to Proceedings of the IEE

A cybernetic approach to prediction with an outline of an adaptive optical computer

This thesis was submitted for the degree of Doctor of Philosophy and awarded by Brunel University.Since the pioneering work of Kolmogoroff and Wiener the use of computing devices to solve problems concerned with - the prediction of future states of a time series has stimulated a large amount of research. Despite all this, however the results have been disappointing. If significant progress were to be made in this field it would lead not only to the possibility of forecasting economic events, the weather, earthquakes, epidemics, and so on, but also -to the possibility of simulating these system. Approaches involving the programming of a computer to carry out this task run into the difficulty of defining the variables involved in a precise enough manner, whereas using the computer -to investigate all the past events of that time series requires a large processing time and an enormous memory store. This thesis examines an approach to this problem which involves the use of a device for processing information in a parallel manner. The system envisaged consists of a holographic recognition device controlled by a digital computer -a combination of analogue and digital techniques. The principle of this device is that developed by Gabor and others, and allows the system to learn to predict the future of a time series. The system learns to predict the future of a time series by using a past length of time series as a training set. Using this training set it attempts to predict the next values of the time series, which can then be compared with the actual time series. The system, then, attempts to optimize its prediction by minimizing the error between the predicted and actual values

Argonne National Laboratory Report ANL-78-66

Report on various studies in the physics division of Argonne National Laboratory

Artificial Intelligence and Ambient Intelligence

This book includes a series of scientific papers published in the Special Issue on Artificial Intelligence and Ambient Intelligence at the journal Electronics MDPI. The book starts with an opinion paper on “Relations between Electronics, Artificial Intelligence and Information Society through Information Society Rules”, presenting relations between information society, electronics and artificial intelligence mainly through twenty-four IS laws. After that, the book continues with a series of technical papers that present applications of Artificial Intelligence and Ambient Intelligence in a variety of fields including affective computing, privacy and security in smart environments, and robotics. More specifically, the first part presents usage of Artificial Intelligence (AI) methods in combination with wearable devices (e.g., smartphones and wristbands) for recognizing human psychological states (e.g., emotions and cognitive load). The second part presents usage of AI methods in combination with laser sensors or Wi-Fi signals for improving security in smart buildings by identifying and counting the number of visitors. The last part presents usage of AI methods in robotics for improving robots’ ability for object gripping manipulation and perception. The language of the book is rather technical, thus the intended audience are scientists and researchers who have at least some basic knowledge in computer science

Experimental and Theoretical Investigations of Anion-pi Interactions Metallacyclic Architectures of First-Row Transition Metals and N-Heteroaromatic Ligands

Research into anion-pi interactions has shifted from attempts to establish the legitimacy of the interaction to the incorporation of anion-pi interactions into supramolecular architectures. The research discussed in this dissertation explores the subtle effects of ligand, anion, and metal ion on supramolecular architectures of tetrazine-based ligands in the context of anion-pi interactions and their importance in the design and synthesis of supramolecular architectures. Computational studies highlight the importance of the arene quadrupole moment, molecular polarizability, and substituent effects on the strength of anion-pi interactions. More importantly, however, this work establishes that there is a distinct directionality inherent to the anion-pi interaction between polyatomic anions and N-heterocycles, which can be used to direct ligands in supramolecular architectures as demonstrated through the work of the Dunbar group in recent years, particularly that of the square and pentagonal metallacycles. The extension of metallacycles of bptz to CoII and FeII demonstrates the ability to tune the size of the metallacyclic cavity by simply changing the metal ion and results in the surprising encapsulation of two [SbF6]- anions in [Fe5(bptz)5(NCCH3)10][SbF6]10. 1H NMR spectroscopy and electrochemical studies reveal slight but significant differences characteristic of the square and pentagonal metallacycles and support the presence of anion-pi interactions in solution and highlight the importance of the encapsulated anion in the templation and stability of the metallacycles. A study of the interconversion between the square and pentagonal metallacycles via 1H NMR is presented for the first time. Increasing the pi-acidity of the chelating ligand from bptz to bmtz results in the encapsulation of only one [SbF6]- anion in [Fe5(bmtz)5(NCCH3)10][SbF6]10, maximizing anion-pi interactions with the ligand despite the tighter fit. A significant hurdle in the incorporation of different anions into the metallacyclic structures was overcome with the development of a new synthetic protocol for [Fe(NCCH3)6]2+ salts of a wide range of anions from sodium salts and Fe4Cl8(THF)6. Also, the nuclearity of the less stable [Fe5(bptz)5(NCCH3)10][PF6]10 metallacycle was established via a combination of MS, electrochemistry and 1H NMR experiments through comparisons with known FeII metallacycle solution behavior

Characteristics of aerosol assisted and conventional chemical vapour deposition of metal oxide thin films on glass, with or without metal dopants

This thesis describes the characteristics and properties of aerosol assisted chemical vapour deposition (AACVD) and conventional atmospheric chemical vapour deposition (CVD) metal oxide thin films on glass substrates with or without metal, Au, Ag, Cu or Al dopants. Host metal oxide matrices including, ZnO and TiO2 with various dopants are known to give specific physical and optical properties desired by many industries and have various potential properties e.g. thermochromic, photochromic and are known as ‘intelligent coatings’. The AACVD synthesis technique was used singularly or in combination with APCVD to achieve thin films on glass substrates either in static or dynamic situations with a range of temperatures (300-600 ºC). Computational fluid dynamics (CFD), Fluent™ software, was used in a 2-equation, numerical study of fluid flow, velocity, particle trajectory, evaporation and thermophoretic effects on six combined AACVD/APCVD vertical reactor head designs; two designs were then selected as experimental prototypes and tested on a pilot rig chosen to more accurately simulate commercial Float glass production. Various functionalities of the thin films were analysed using transmittance/reflectance spectroscopy, RZ ink and stearic acid photocatalysis tests, resistivity and a variety of analytical techniques including SEM, XRD and XPS were used. The main findings include the effect of noble metal dopants (particularly Au and Ag), substrate synthesis temperature, fluid flow and droplet size have on the physical and chemical properties such as the morphology, crystallinity, water surface contact angle of the host metal oxide matrices. The nebulised AACVD droplet size, for solvent systems, are critical for deposition of the precursor chemicals onto the surface of the substrate, CFD particle trajectory of nebulised AACVD methanol droplets were calculated to be 1 order of magnitude too small to overcome the main forces of influence aerodynamic drag and at higher synthesis temperature evaporation