Abstract: In this thesis we investigate the emergence of new phenomena in multigap superconductors and multicomponent Ginzburg-Landau theories in the presence of intraband and cross-band pairing. The first part contains a review of emergent phenomena in superconductors with only intraband pairing, in particular the mechanism behind gap resonances which are accompanied by Higgs and Leggett modes. Then we study the gap resonances induced by two-dimensional quantum confinement and describe its spatial profile using the Bogoliubov-de Gennes equations. In the second part we describe the conditions where the cross-band pair formation is feasible. Using the formalism of Green functions we obtain the equations governing the interplay between intraband and cross-band pairing. Also, we derived the Ginzburg-Landau equations considering both intraband and cross-band pairing. Finally, we describe the crossover between the intraband-dominated and crossband-dominated regimes. These two are delimited by a tendency towards a gapless state. When a magnetic field is applied close to the gapless state, we found new arrangements of vortices like square lattices, stripes, labyrinths or of vortex clusters. The experimental signatures and consequences of crosspairing are discussed for MgB2 and Ba0.6K0.4Fe2As2.

Abstract: Recent development, present state and expected future developments in energy-dispersive X-ray spectrometry are discussed. Attention is paid to the improvements in analytical selectivity, sensitivity, detection limit, quantitative character and applicability range, which are the result of new or better excitation sources, detectors, instrument design, automation, computer software and theoretical developments.

Abstract: BACKGROUND Simultaneous anammox and denitrification (SAD) can remove carbon and nitrogen. However, its performance is suppressed under saline surroundings. In this work, mannitol was used to enhance a SAD process treating saline wastewater. RESULTS The optimum carbon and nitrogen removal was achieved at 0.2 mmol L-1 mannitol, during which ammonium removal efficiency (ARE), nitrite removal efficiency (NRE) and chemical oxygen demand (COD) removal efficiency were 96.95%, 93.70% and 90.05%, respectively. The maximum ammonium removal rate (ARR), nitrite removal rate (NRR) and the specific anammox activity (SAA) were increased by 25.49%, 55.84% and 33.83% with optimum addition (0.2 mmol L-1 mannitol) respectively. The diameter of sludge was enlarged with the addition of mannitol (<= 0.2 mmol L-1). The Tseng-Wayman model was more suitable to simulate the whole SAD process. The modified logistic model, the modified Boltzman model and the modified Gompertz model were all appropriate to describe nitrogen removal in a typical cycle with the addition of mannitol. CONCLUSION Mannitol was effective in enhancing a SAD process treating saline wastewater, and maximum nitrogen removal was achieved at mannitol = 0.2 mmol L-1. The Tseng-Wayman model satisfactorily predicted the whole SAD process treating saline wastewater with mannitol addition. (c) 2018 Society of Chemical Industry

Abstract: The use of a photocatalyst (photosensitizer) which produces singlet oxygen instead of enzymes for oxidizing analytes creates opportunities for designing cost-efficient and sensitive photoelectrochemical sensors. We report that perfluoroisopropyl-substituted zinc phthalocyanine (F64PcZn) interacts specifically with a complex phenolic compound, the antibiotic rifampicin (RIF), but not with hydroquinone or another complex phenolic compound, the antibiotic doxycycline. The specificity is imparted by the selective preconcentration of RIF in the photocatalytic layer, as revealed by electrochemical and optical measurements, complemented by molecular modeling that confirms the important role of a hydrophobic cavity formed by the iso-perfluoropropyl groups of the photocatalyst. The preconcentration effect favorably enhances the RIF photoelectrochemical detection limit as well as sensitivity to nanomolar (ppb) concentrations, LOD = 7 nM (6 ppb) and 2.8 A.M-1.cm(-2), respectively. The selectivity to RIF, retained in the photosensitizer layer, is further enhanced by the selective removal of all unretained phenols via simple washing of the electrodes with pure buffer. The utility of the sensor for analyzing municipal wastewater was demonstrated. This first demonstration of enhanced selectivity and sensitivity due to intrinsic interactions of a molecular photocatalyst (photosensitizer) with an analyte, without use of a biorecognition element, may allow the design of related, robust, simple, and viable sensors.

Abstract: The mobilization of arsenic (As) in aquatic environment (groundwater) can cause severe environmental and healthy issues. To develop remediation strategies, we proposed a comprehensive mathematical model to describe the As removal in a arsenite (As (III)) oxidizing and ferrous iron (Fe (II)) oxidizing denitrifying granular biofilm system. In the model framework, the growth-linked microbial oxidation of As (III) and Fe (II) was coupled to chemolithotrophic denitrification of one-step reduction of nitrate to nitrogen gas. Meanwhile, the precipitation of ferric iron (Fe (III)) and adsorption of arsenate (As (V)) onto the biogenic Fe (III) (hydr)oxides were also considered. The model was calibrated by comparing the model predictions against experimental data from batch experiments. The validity of the model was further demonstrated through testing against long-term experimental results from five independent bioreactors with different reactor configurations and operational conditions. Modeling results revealed that the granule size would exert a limited impact on arsenic and iron removal. Nevertheless, their removal efficiencies increased rapidly with the increase of hydraulic retention time (HRT) from 1 h to 12 h, but became independent of HRT as it further increased. The established model framework enables interpretation of a range of experimental observations on As and Fe removal and helps to identify the optimal conditions for enhanced arsenic remediation. (C) 2017 Elsevier Ltd. All rights reserved.

Abstract: Mixed-culture biotechnologies are widely used to capture nutrients from wastewater. Purple non-sulfur bacteria (PNSB), a guild of anoxygenic photomixotrophic organisms, rise interest for their ability to directly assimilate nutrients in the biomass. One challenge targets the aggregation and accumulation of PNSB biomass to separate it from the treated water. Our aim was to enrich and produce a concentrated, fast-settling PNSB biomass with high nutrient removal capacity in a 1.5-L, stirred-tank, anaerobic sequencing-batch photobioreactor (SBR). PNSB were rapidly enriched after inoculation with activated sludge at 0.1 gVSS L–1 in a first batch of 24 h under continuous irradiance of infrared (IR) light (>700 nm) at 375 W m–2, with Rhodobacter reaching 54% of amplicon sequencing read counts. SBR operations with decreasing hydraulic retention times (48 to 16 h, i.e., 1–3 cycles d–1) and increasing volumetric organic loading rates (0.2–1.3 kg COD d–1 m–3) stimulated biomass aggregation, settling, and accumulation in the system, reaching as high as 3.8 g VSS L–1. The sludge retention time (SRT) increased freely from 2.5 to 11 days. Acetate, ammonium, and orthophosphate were removed up to 96% at a rate of 1.1 kg COD d–1 m–3, 77% at 113 g N d–1 m–3, and 73% at 15 g P d–1 m–3, respectively, with COD:N:P assimilation ratio of 100:6.7:0.9 m/m/m. SBR regime shifts sequentially selected for Rhodobacter (90%) under shorter SRT and non-limiting concentration of acetate during reaction phases, for Rhodopseudomonas (70%) under longer SRT and acetate limitation during reaction, and Blastochloris (10%) under higher biomass concentrations, underlying competition for substrate and photons in the PNSB guild. With SBR operations we produced a fast-settling biomass, highly (>90%) enriched in PNSB. A high nutrient removal was achieved by biomass assimilation, reaching the European nutrient discharge limits. We opened further insights on the microbial ecology of PNSB-based processes for water resource recovery.