Miracle-dz/UniFAR-FTUs huggingface dataset:
Photocatalytic removal of taste and odour compounds for drinking water treatment

Photocatalytic degradation of geosmin and 2-methylisoborneol (MIB), which are two taste and odour compounds commonly found in drinking water supply sources, was investigated using an immobilised TiO2 photoreactor. It was found that the degradation of geosmin and MIB followed similar pseudo-first-order kinetics with reaction rate constants being approximately 0.025 min-1 for typical geosmin and MIB concentrations of 250 and 500 ng/L. The normalised formal quantum efficiency was calculated to be in the range of 162–182 L/mol. Influence of additives (i.e. sodium bicarbonate and alcohols) on the degradation process was also investigated. It was found that there was a small reduction in the degradation rate constants of geosmin and MIB with increasing sodium bicarbonate concentration. At 50 mg/L sodium bicarbonate the degradation rate constants decreased by approximately 5%. Similarly, for methanol and ethanol concentrations up to 35 and 50 mg/L, respectively, these constants were found to also decrease. While addition of sodium bicarbonate and alcohols was seen to have relatively small negative effects on the photocatalytic degradation performance, the magnitude of their influence was consistent with the hypothesis that the degradation mechanism of geosmin and MIB was predominately that of attack involving HO∙ radicals.
Nutrient Dynamics During Flood Events in Tropical Catchments: A Case Study in Southern Vietnam

Assessing surface water quality variation as well as chasing water pollution sources is essential for water quality management. However, for existing conditions in developing countries, this assessment may not be done properly in many affected catchments due to limited data and lacking of tools. In particular, pollutant transport from the catchment to its river system during flood events needs quantification and is the aim of the study. For this, a combined water quality monitoring and modeling approach is proposed. The study was exemplarily performed for a typical ungauged medium scale catchment located in the southern area of Vietnam. The available budget allowed at least a limited monitoring of nutrients and driven parameters (e.g., flow, sediment). These data were used to, in total, successfully calibrate the complex Hydrological Simulation Program-Fortran (HSPF) model. The results lead to three main conclusions: (1) the contributions of point and diffuse sources to nutrient loadings could clearly be identified with the help of monitoring; (2) water quality sampling during flood events is critical to assess pollution sources, especially, diffuse ones. However, just a monitoring of data alone is not adequate to interpret the observed concentrations; modeling is required. (3) Despite of the limited amount of data, which could be recorded and processed during the study, a representative catchment modeling during floods could be performed. It delivered essential information for linking pollution sources with water quality data. Furthermore, the limits of an application of the complex HSPF model under given conditions were shown.
Diagnostics and control of radio‐frequency glow discharge

The diagnostics of 13.56 MHz planar radio‐frequency (rf) plasma were carried out using spatially resolved optical emission spectroscopy between the parallel electrodes. Plasma sheath thickness d evaluated from the optical emission profiles depends on gas pressure P, and a relationship of Pnd=const. was obtained for CH4, CF4, and O2 plasmas with n≥1/3, and for He and Ar plasmas with n≥1/2. The etching rate and the etching profile of silicon in CF4 plasma were also examined as a function of gas pressure. A novel technique for controlling rf plasmas using the optical sheath thickness and maximum optical emission intensity is presented. This technique was applied to dry etching of silicon in CF4 plasma. When this novel control technique was used, the deviation in the etched depth for a constant etching time became smaller than that obtained using conventional power control methods.
Subcellular distribution and chemical forms of chromium in rice plants suffering from different levels of chromium toxicity

The subcellular distribution and chemical forms of different heavy metals in rice are correlated with their bio-toxicity. An experiment was conducted to investigate the subcellular distribution and chemical forms of chromium (Cr) in two rice genotypes (Oryza sativa L. cv. Xiushui 113 and cv. Dan K5) differing in Cr accumulation, to understand the mechanisms of Cr toxicity and resistance in rice plants. The results show that Cr in the roots of rice plants exposed to Cr stress was mainly localized in cell walls, whereas Cr in leaves and stems was mainly present in both cell walls and vacuoles, suggesting that both compartments act as important protective barriers against Cr toxicity in rice plants. Although Cr ions in all plant tissues exist predominantly in the forms extracted by 80% ethanol and distilled water, the amount of Cr in the chemical forms extracted by 2% HAc, 0.6 M HCl, and in residues was significantly increased under the highest Cr level (100 μM Cr) compared to the plants grown under lower Cr levels. These results indicate that excess Cr accumulated in rice plants under Cr stress is bound to undissolved or low-bioavailable compounds, such as undissolved phosphate and oxalate, being beneficial for rice plants to alleviate Cr toxicity. In addition, under the highest Cr level (100 μM), Dan K5 had a higher percentage of Cr in the chemical forms extracted by 2% HAc, 0.6 M HCl, and in residues compared to Xiushui 113 in both stems and leaves, indicating that more Cr ions in shoots of Dan K5 were bound to undissolved or low-bioavailable compounds, in comparison with those of Xiushui 113. It is evident that the low bioavailability of Cr in the shoots of Dan K5 is related to a high Cr accumulation.
Development and physicochemical characterization of dexamethasone-loaded polymeric nanocapsule suspensions

The influence of drug concentration, oil phase, and surfactants on the characteristics of dexamethasone-loaded nanocapsules was investigated. The best formulations were obtained at dexamethasone concentrations of 0.25 and 0.50 mg.mL-1 (encapsulation efficiency: 80-90%; mean size: 189-253 nm). The type of oil phase influenced only the stability of dexamethasone-loaded nanocapsules. The association of polysorbate 80 and sorbitan monooleate provided a more stable formulation. Sunflower oil and sorbitan sesquioleate used for the first time as oil phase and surfactant for nanocapsules, respectively, have allowed obtaining suspensions with low mean size and narrow size distribution.
tempo vivo da memória: ensaios de psicologia social

Ecléa Bosi, no livro O tempo vivo da memória: ensaios de psicologia social, chama a atenção para a importância do estudo do passado recente e mostra que a memória oral é um precioso instrumento na constituição da crônica do cotidiano, à medida que pode funcionar como uma espécie de elo entre diferentes tempos. A autora faz indagações acerca da valorização atual da tradição oral e afirma que a formação de identidade se alimenta dos vínculos com o passado.
Optical Waveguide Spectrometry of Acridine Orange in Monolayer and Langmuir−Blodgett Film

The absorption spectrum of acridine orange in a monolayer or an LB membrane is studied using optical waveguide (OWG) spectrometry. Octadecyl acridine orange (C18-AO) is incorporated into the stacked base pairs of octadecyl adenine (C18-Ade) and octadecyl thymine (C18-Thy), which are known to form a stable monolayer at air−water interfaces. Visible absorption spectra of the monolayer, which are difficult to obtain by conventional spectrometry, are easily generated by OWG spectrometry. A linear relation between the absorbance of C18-AO and the amount of monolayer deposited on the substrate was clearly discerned. This suggests that quantitative analysis of the monolayer can be performed by OWG spectrometry. Quantitative analysis can also be made of the structure of LB films. The absorbance at 500 nm, which is a characteristic of acridine orange, increased proportional to the number of layers on the substrate. The principal advantage of OWG spectrometry is in detecting the absorbance of molecules on any subst.
The Synthesis of Salvinolone, Saprorthoquinone, and 4-Hydroxysapriparaquinone from (+)-Dehydroabietic Acid

Salvinolone, saprorthoquinone, and 4-hydroxysapriparaquinone isolated from the roots of Salvia prionitis Hance. were synthesized starting from (+)-dehydroabietic acid via 11,12-dimethoxyabieta-8,11,13-trien-7-one and 12-methoxyabieta-8, 11,13-triene.
Study of phase behavior on chitosan/viscose rayon blend film

A blend of chitosan and viscose rayon was investigated. A film was made from regenerating the blend of chitosan and viscose rayon. The film was characterized by various techniques, including Fourier transform infrared spectroscopy (FTIR), wide-angle X-ray scattering (WAXS), differential scanning calorimetry (DSC), dynamic mechanical analysis (DMA), and transmission electron microscopy (TEM). The phase behavior of the blend is influenced by its composition with or without carboxymeth-ylated chitosan (CM-Cs). Characterization of the chitosan/viscose rayon (Cs/VR) blend by DSC and DMA suggests partial compatibility of chitosan with VR and lack of compatibility in the remaining cases. Results of the TEM show that the addition of CM-Cs into the blend can improve the compatibility of Cs with VR. © 1998 John Wiley & Sons, Inc. J Appl Polym Sci 67:1965–1972, 1998
Application of a modified Dubinin-Radushkevich equation to adsorption of gases by coals under supercritical conditions

The classic Dubinin−Radushkevich (DR) equation, which is used to describe the adsorption of gases, requires a “saturation pressure” in its calculation, which is not defined for supercritical conditions. By using gas density instead of gas pressure (and adsorbed phase density rather than saturation pressure) to describe the sorption of the gas onto the surface, the DR equation can be applied in supercritical conditions. A proportionality term (k times the gas density) was added to this modified DR equation to account for possibilities such as Henry's law dissolution by the coal, errors in cell volume and helium density, and differences in the accessibility to coal between helium and the other gases. The sorption characteristics of three dry Australian bituminous coals when exposed to carbon dioxide, methane, and nitrogen were measured over the range 0−20 MPa at 53 °C. The data were fitted by the modified DR equation to within 1% of the sorption capacity across the isotherm in nearly all cases, substantiall.
Bioassisted Room‐Temperature Immobilization and Mineralization of Zinc Oxide—The Structural Ordering of ZnO Nanoparticles into a Flower‐Type Morphology

od library. Different amounts of this mixture were dispensed using a micropipette (Brand Transferpette) in the different columns. Solvent was evaporated under ambient conditions. Thicknesses were characterized using a stylus profilometer (Dektak 3M). The same mixture of solvents was used for the composition–period libraries. The exposure was performed using an USHIO lithographic system (filter at 365 nm, intensity 5 mW cm). After exposure and heating, all the samples were fully polymerized by flood exposure for 10 min and heating at 80 °C for an additional 10 min to fix the relief structure. We checked that this step had a minor influence on the final relief structure. The topography was measured using an automated atomic force microscope (NT-MDT Solver P7 LS, Moscow, Russia) with a motorized Yh-stage. The stage moves automatically to the 44 programmed coordinates on the sample surface corresponding to different processing conditions (e.g., energy–period, temperature–period). In case of the temperature–period library, the sample was virtually divided into 44 samples (11 × 4) and temperatures were estimated using a contact thermometer. All samples were prepared in a clean room (class 100).
Maturity Tests for Composts — Verification Of a Test Scheme for Assessing Maturity

Increased recycling of organic wastes has raised concern about the quality of compost end products. In addition to the limit values for heavy metals and impurities including weeds and pathogens, the quality criteria for compost products should also include criteria for maturity. There is a tremendous number of maturity assays, developed earlier by several authors, and recommended to be used to evaluate maturity of composts. Because no such single test alone reliably demonstrates the complex properties occurring during maturization of compost, we developed a fast and easy-to-use two-phase test scheme for the assessment of maturity. In the first phase the degradation phase e.g. stability of compost samples is evaluated by using a carbon dioxide evolution test and/or determination of the NO3-N/NH4-N ratio by simple test strips. In the second phase, the toxicity of the compost is evaluated by a plant growth test, germination tests and/or the Flash bioluminescence test. Eleven plants composting sewage sludge, source-separated biowaste, manure or a combination of these raw materials were sampled after 1-3 weeks of composting and when the compost was considered “ready for use”. Chemical and physical analyses were considered useful as additional information when evaluating maturity especially when the results were not conclusively clear. This fast and easy-to-use test scheme was designed especially for the composting plant operators and official laboratories responsible for evaluating compost quality.
Ultra-Microscale (5–25 μg C) Analysis of Individual Lipids by 14C AMS: Assessment and Correction for Sample Processing Blanks

Measurements of the natural abundance of radiocarbon in biomarker molecules can be used to elucidate the biogeochemical roles of marine bacteria and archaea in the oceanic water column. However, the relatively low concentration of biomass, especially below the euphotic zone, inevitably results in small sample sizes for compound-specific analyses. In ultra-microscale Δ14C measurements, which we define as measurements on samples smaller than 25 μg C, the process of isolating pure compounds and preparing them for measurement adds significant background carbon. This additional blank carbon can contribute up to 40% of the total sample mass; therefore, it is necessary to quantify all components of the processing blank in order to make appropriate corrections. Complete propagation of error is critical in order to report the correct analytical uncertainty. The carbon blank is composed of at least 3 different sources: i) those that scale in proportion to the mass of the sample; ii) sources that contribute a constant mass of blank, e.g. closed-tube combustion; and iii) contaminants from vacuum lines and/or other aspects of sample handling that are difficult to quantify. We approached the problem of correcting for the total sample processing blank by deriving a 4-part isotopic mass balance based on separating the 3 exogenous components from the sample. Subsequently, we derived the appropriate equations for the full propagation of error associated with these corrections. Equations for these terms are presented. Full treatment of a set of raw data is demonstrated using compound-specific Δ14C data from the North Central Pacific water column.
Treatment of Arsenic Contaminated Groundwater using Oxidation and Membrane Filtration

ii I hereby declare that I am the sole author of this thesis. This is a true copy of the thesis, including any required final revisions, as accepted by my examiners. I understand that my thesis may be made electronically available to the public. Abstract Arsenic is a known carcinogen, causing cancers of the skin, lungs, bladder and kidney. Current research suggests that drinking water is the most common pathway for long-term low dose exposure. Arsenic contaminated drinking water has caused serious health problems in many countries including: Nanofiltration (NF) is a promising technology for arsenic removal since it requires less energy than traditional reverse osmosis membranes. Several studies have shown that nanofiltration is capable of removing the oxidized form of arsenic [As(V)] while the reduced form of arsenic [As(III)] is poorly removed. To exploit this difference it has been suggested that a pretreatment step which oxidizes the As(III) to As(V) would improve the performance of membrane filtration, but this has never been demonstrated. The research had three objectives: The first was to investigate the ability of NF membranes to treat arsenic contaminated groundwater and evaluate the influence of the membrane type and operating conditions. Secondly, the effectiveness of a solid phase oxidizing media (MnO 2) to oxidize arsenite to arsenate was investigated. Lastly, the MnO 2 was combined with NF membrane filtration to determine the benefit, if any, of oxidizing the arsenic prior to membrane filtration. A pilot membrane system was installed to treat a naturally contaminated groundwater in Virden, Manitoba, Canada. The groundwater in Virden contains between 38 and 44 μg/L of arsenic, primarily made up of As(III), with little particulate arsenic. In the first experiment three Filmtec ® membranes were investigated: NF270, NF90 and XLE. Under all conditions tested the NF90 and NF270 membranes provided insufficient treatment of Virden's groundwater to meet Canada's recommended Interim Maximum Acceptable Concentration (IMAC) of 25 μg/L. The XLE membrane provided better arsenic removal and under the conditions of 25 Lmh flux and 70% recovery produced treated water with a total arsenic concentration of 21 μg/L. The XLE membrane is therefore able to sufficiently treat Virden's ground water. However treatment with the XLE membrane alone is insufficient to meet the USEPA's regulation of 10 μg/L or Canada's proposed Maximum Allowable Concentration (MAC) of 5 μg/L. The effects of recovery and flux on total arsenic passage are consistent with accepted membrane theory. Increasing …
Kinetic Study of the Urethane and Urea Reactions of Isophorone Diisocyanate

Kinetic studies of the catalyzed urethane reactions between isophorone diisocyanate (IPDI) and alcohols and of the urea reactions between an isocyanate-terminated prepolymer [IPDI–PPG2000–IPDI, where PPG2000 is poly(propylene glycol) with a number-average molecular weight of 2000 g/mol] and water in the bulk state were performed with Fourier transform infrared (FTIR) spectroscopy. Dibutyltin dilaurate was used as the catalyst for the urethane reaction, and various tertiary amines were used as catalysts for the urea reactions. The reactions were followed through the monitoring of the change in the intensity of the absorbance band for NCO stretching at 2270 cm−1 in the FTIR spectra; the activation parameters were determined through the evaluation of the kinetic data obtained at various temperatures (within the range of 30–60°C). The kinetic data indicated that the catalyzed isocyanate/alcohol and isocyanate/water reactions both followed second-order kinetics during their initial stages but later followed third-order kinetics resulting from the autocatalytic effects of hydrogen bonding between the hydroxyl groups and the newly formed urethane and urea groups. Furthermore, activation energies of 64.88 and about 80 kJ/mol for the isocyanate/alcohol and isocyanate/water reactions, respectively, indicated that the urea-forming reactions were more sensitive to the reaction temperature than the urethane-forming reactions. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci 2008
Synthesis and properties of conjugated polymers containing 3,9- and 2,9-linked carbazole units in the main chain

Novel conjugated polymers containing 3,9- or 2,9-linked carbazole units in the main chain were synthesized by the polycondensation of ethynyl- and iodo-substituted 9-arylenecarbazolylene monomers, and their optical and electrical properties were studied. Polymers with weight-average molecular weights of 3400–12,000 were obtained in 76–99% yields by the Sonogashira coupling polycondensation in piperidine or tetrahydrofuran (THF)/piperidine at 30 °C for 48 h. All the 3,9-linked polymers absorbed light around 300 nm. The para-phenylene-linked polymer also absorbed light around 350 nm, while meta-phenylene-linked one did not. The 3,9-linked polymers absorbed light at a wavelength longer than the 2,9-linked one. The polymers emitted blue fluorescence with high quantum yields (0.21–0.78) upon excitation at the absorption maxima. The polymers were oxidized around 0.6 V, and reduced around 0.5 V. Poly(1) showed the dark conductivity of 3.7 × 10−11 S/cm (103 V/cm). © 2009 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 47: 3506–3517, 2009
Effect of Sparger Surface Area on Bubble Diameter in Flotation Columns

AbstractThe effect of the parameter column cross-sectional area to sparger surface area Rs , on bubble diameter db , is determined for four sparger types, ceramic, stainless steel, rubber and filter cloth. Rs should be less than about 1 for generation of uniform-sized bubbles and operation in bubbly flow conditions. For Rs ≤ 1db is related to Rs by db = C 1[Rs · Vg ]n where Vg is the superficial gas velocity and C 1 and n are empirical constants; the product [Rs · Vg ] is equivalent to volumetric gas rate per unit area of sparger. The effect of sparger type appears to be relatively minor and a general relationship is proposed db = C 1[Rs · Vg ]0.25, where C 1 is dependent on the solution chemistry. Based on the findings, a methodology for sparger scale up is proposed.
Evidence for Two Distinct Positive Trapped Charge Components in NBTI Stressed p-MOSFETs Employing Ultrathin CVD Silicon Nitride

Besides the generation of interface states and the associated positive trapped charge ( ), experimental results unambiguously show the generation of another positive trapped charge component ( ) during negative-bias temperature instability (NBTI) stressing of p-MOSFETs employing ultrathin silicon nitride gate dielectric. For a given gate stress voltage, is generated at a much faster rate compared to . Under the pulsed gate condition studied, could almost be completely annihilated, regardless of the NBTI stress voltage, whereas only partial annihilation of is observed. This more resistant nature of to post-stress relaxation has serious implications on the dynamic NBTI reliability of these p-MOSFETs.
Comparison of Analysis Methods for the Calculation of Degradation Rates of Different Photovoltaic Technologies

The degradation rates of crystalline silicon (c-Si) and thin-film photovoltaic (PV) systems of different manufacturers and different technologies were calculated and compared for the systems’ first five years of outdoors exposure, by applying a host of different analysis methods, in order to quantify the differences between each method. These include linear regression using linear least squares (LLS), classical seasonal decomposition (CSD) and seasonal-trend decomposition by Loess (STL) on daily and monthly time series of two performance metrics, performance ratio (PR) and PR with temperature correction (PR-TC). The comparison of the resulting degradation rates for each PV group (c-Si and thin-film) showed that the monthly PR-TC-STL method provided the lowest standard deviation and a mean degradation rate of 1.12 %/year for the c-Si PV systems. On the other hand, the daily PR-TC-LLS method demonstrated the lowest standard deviation and an average degradation rate of 2.47 %/year for the thin-film PV systems. Linear regression using LLS produced the lowest degradation rates overall, but when temperature correction was applied, the calculated degradation rates were increased by 0.4 %/year. LLS also showed the lowest standard deviation for the thin-film PV systems, which was further reduced by applying temperature correction.