The nitrates content in 12various sorts of vegetables and potatoes was measured in years 2005 - 2007 using nitrate ion selective electrode. From total number 539 of analyzed samples 72 samples exceeded the maximal limit concentration of nitrates. Most frequently non-permissible values were found in the kohlrabi (26 samples from 44), radish (18 from 45), potatoes (8 from 48), root parsley (4 from 26), red beet (4 from 27) and white cabbage (6 from 45). Absolutely highest content of nitrates was measured in kohlrabi 4 610 mg NO3-.kg-1(in fresh matter) and red beet 4 977 mg NO3-.kg-1. Although over 13 % of samples exceeded limits of nitrates given by law, in generally, can be assumed that positive factors from vegetables consumption play more important role than potential risc from possible nitrates overdosage.

nÃo hà / Neste ensaio investiga-se a perda de conteÃdo dos modelos de previsÃo autoregressivos, na medida em que se alarga o horizonte temporal no qual a variÃvel à estimada. O conteÃdo à medido pela reduÃÃo relativa do erro quadrado mÃdio que o modelo proporciona em comparaÃÃo ao processo simplificado de utilizar a mÃdia incondicional da sÃrie temporal. A variÃvel estudada à a arrecadaÃÃo mensal do Imposto sobre CirculaÃÃo de Mercadorias e ServiÃos (ICMS) proveniente do segmento de energia elÃtrica, no Estado do CearÃ, no perÃodo de janeiro de 1999 a setembro de 2010. Utiliza-se o mÃtodo e o modelo computacional formulados por Galbraith (2003), analisando-se a forecast content function, na qual o conteÃdo depende do nÃmero de perÃodos estimados. Os resultados confirmam que, para a sÃrie temporal explorada, quando se eleva o alcance da previsÃo o conteÃdo decai rapidamente, podendo atingir valor inferior a 10% quando o horizonte da previsÃo chega a 5 meses. Verificou-se, ademais, que o uso de sub-amostras via descarte de perÃodos mais antigos agrava a perda de conteÃdo. / In this essay we investigate the loss of content in autoregressive forecast models, as it is increased the horizon of time in which the variable is estimated. The content is measured as the proportionate reduction in medium squared error (MSE) that the model gives, comparing to the simple process by using the unconditional mean of time series. The variable is the monthly collection of ICMS from electric power sector, in Cearà state, in the period from January 1999 to September 2010. We use the method and computational model formulated by Galbraith (2003), analyzing the forecast content function, in which the content depends on the number of estimated periods. The results confirm that, when it increases the range of forecast the content decays quickly, reaching less than 10% when the forecast horizons reaches 5 months. It was found further that the use of subsamples by discarding oldest periods increases the loss of content.

Long term management of lodgepole pine depends, in part, on the nutrient capital of the site. Harvesting has been shown to increase the availability of nitrogen and other nutrients for a limited period of time. This increase, or nutrient flush, following cutting has been attributed to several factors including changes in organic matter quantity and quality, soil moisture and temperature regimes, and competition for nutrients. Knowledge of the duration and the magnitude of the nutrient flush would be valuable for management decisions. A consequence of lodgepole pine clearcuts was studied for soil nitrogen availability and microclimate. Mineral soil and forest floor samples were anaerobically incubated and analyzed for ammonium-nitrogen (ppm). The mineral soil showed a flush lasting about 12 years, peaking by year 8, while the forest floor material showed no trend. The size of the increase from year 2 to year 8 was about 52%. Temperature (air and soil), soil moisture, solar radiation, and precipitation data were collected, and a soil water budget was calculated using a simple water balance model. The average calculated soil water deficit was 119 mm, but this may have been an over-estimate. Windrowing following cutting may have depleted the site nitrogen reserve which in turn reduced the amount that was mineralized during incubation. The interaction between the soil temperature and moisture may have further limited nitrogen availability to the lodgepole pine trees. It is concluded that the dynamics of nitrogen availability following clearcutting are important for the establishment and growth of lodgepole pine. The summer moisture deficit appears to limit the nitrogen mineralization rate as well as seedling growth. / Forestry, Faculty of / Graduate

The oxidation of sulfidic mine tailings and subsequent acid and salt accumulation results in acid drainage and poses a severe reclamation problem. The objectives of this study were to quantify the processes leading to these problems and propose feasible solutions. Characterization of 120 sulfidic surface samples, collected from the Sullivan mine tailings ponds, was carried out for dominant physiological groups of microorganisms, sulfur forms, water and acid extractable cations qualitative physical characteristics, pH, conductivity, organic matter and moisture content. Acid tolerant fungi and iron, sulfur and acid tolerant heterotrophic bacteria were enumerated by the most-probable-number technique. Iron bacteria (Thiobacillus ferrooxidans) occurred often and can be implicated as the cause of Fe⁺² oxidation in samples not buffered at near neutral pH values by bases. Sulfur bacteria (thiobacillus species were commonly found and classified as T. thioparus, T. neapolitanus, or T. thiooxidans. A pH-dependent succession of these thiobacilli occurs in the tailings. Acid tolerant heterotrophic bacteria populations were highly correlated with those of the thiobacilli suggesting a symbiotic relationship, particularly in samples with pH >2.5. The numbers of acid tolerant fungi tended to increase proportionally with oxidation, suggesting increased colonization with time. Chemical analysis for major sulfur forms indicates that iron mono- sulfide oxidation is rapid resulting in the formation and persistence of Fe⁺³ (as amorphous Fe oxyhydroxides in mineralogical analysis) and elemental sulfur. Some accumulation of other oxidizable sulfur forms is indicated by the high levels of total oxidizable sulfur. A portion of this sulfur not accounted for by CS₂ extractable elemental sulfur may be present as amorphous elemental sulfur. The oxidation of elemental sulfur and other sulfur intermediates to sulfate is pronounced in the surface 0-2 cm based on the laboratory oxidation of a bulk tailings sample. Mineralogical analysis shows that gypsum is the predominant sulfate containing mineral at basic to slightly acid pH values. Under moderately to strongly acid conditions, jarosite type minerals occurred in high amounts. Mineralogical analysis also showed that the decomposition of basic minerals and chlorite occurred initially, with the dissolution of micas and K-feldspars being less rapid. The absence of detectable kaolinite or other Al silicate residues indicates that alumino-silicate dissolution may be congruent. Mineralogical results showing dissolution of minerals is supported by general increases in water extractable cations (including Fe, Al, Ca, Mg, K and Na) and decreases in these same acid extractable cations as weathering proceeds. These processes ultimately result in a highly oxidized surface in which acid production is slow. It is suggested that erosional processes be inhibited where an oxidized surface exists to prevent the exposure of reduced tailings beneath the surface. Furthermore, steps should be taken to minimize the addition of fresh tailings over oxidized surfaces. The use of correlations between the qualitative physical characteristics texture, structure and color, obtained in this study, can serve as guides to estimating the degree of tailings oxidation in the field. If more precision is required, the colorimetric determination of CS₂ extractable elemental sulfur is suggested, particularly on the more oxidized samples. Proper management of the tailings to maintain present oxidized surfaces should reduce the acid drainage considerably until reclamation is undertaken. The quantification of the changes in tailings properties with increases in weathering can be useful in evaluating reclamation strategies. / Land and Food Systems, Faculty of / Graduate

American bureaucracies are often assigned inconsistent goals, expectations, roles, and functions (Goodsell, 2004; Lipsky, 2010), exemplified in probation by Klockars’ (1972) classical dilemma of corrections that describes a punitive-rehabilitative dichotomy. A failure to prepare bureaucrats in corrections to address the classical dilemma this results in probation officers (POs) making decisions between and among competing options that consequently generally emphasize only one of the primary goals of probation (Ellsworth, 1990). This dissertation offers insight into and prompts rethinking of how corrections agencies prepare POs to address the classical dilemma. Few studies focus on how organizations educate POs to address the classical dilemma. This dissertation applies ethnographic content analysis to examine the messages communicated to correctional probation officers in the 95 lessons of the curriculum used by Florida Department of Corrections (FDC) to train new officers. To analyze the data and the meaning conveyed by the FDC I applied Saldana’s (2016) 5Rs framework of rules, routines, roles, rituals, and relationships. / Includes bibliography. / Dissertation (Ph.D.)--Florida Atlantic University, 2020. / FAU Electronic Theses and Dissertations Collection

Application of carbon nanomaterials like fullerene, carbon nanotubes, and graphene in solar cells using solution processable methods presents a great potential to reduce the cost of producing electricity from solar energy. However, carbon nanotubes and graphene materials are predominantly metallic and this limits their function in organic photovoltaic devices (OPVs) where semiconducting behavior is required. Doping of carbon nanomaterials is a well-known method for making them semiconducting. Doping of carbon nanomaterials with nitrogen and boron can tune their properties to suit the requirements for use in photovoltaic applications as n-type and p-type semiconducting materials, respectively. Indeed, the use of nitrogen doped and boron doped carbon nanotubes in organic solar cells together with fullerene acceptors can improve the current density of the OPV devices. Nitrogen doping of carbon nanotubes can be achieved by using nitrogen-containing precursor materials during chemical vapor deposition. However the doping of carbon nanotubes with nitrogen does not automatically make them n-type materials; they remain metallic unless a large amount of quaternary type nitrogen is incorporated in the carbon nanotubes. In this work we have developed a method to control the type of nitrogen that is incorporated in CNTs by using an appropriate synthesis temperature and use of oxygen-containing carbon precursors during the chemical deposition of carbon nanotubes. Quaternary N was incorporated in a CVD process when high temperatures and a high concentration of O in the precursor materials were used. We also showed that the type and amount of N can be changed from pyrrolic and pyridinic-N-oxide to pyridinic N and quaternary N by annealing N doped carbon nanotubes at temperatures above 400°C. At temperatures above 800°C most of the nitrogen is converted to quaternary nitrogen. N-CNT thin films were used in OPVs so as to modify the ITO electrode and transform it into a 3D electrode. The resulting effect was an improved short circuit current density in the devices containing an N-CNT thin film that was placed on top of the ITO electrode. A reduction in efficiency losses in OPVs at increasing light intensity was observed in the NCNT ITO modified electrode OPVs. This is a remarkable finding when considering that one of the main problems hindering commercialization of OPVs is the loss of efficiency at high light intensities. We related these effects to the efficient charge collection by the modified ITO electrode. Incorporation of N-CNTs in the bulk heterojunction layer of the OPV device resulted in poor performance when compared to an OPV device made without N-CNTs. This effect is caused by shorting of the OPVs. We used a method of incorporating N-CNTs whilst minimizing shorting and this showed potential for better performance. A study on the attempted doping of graphene with B to make it a p-type material showed that in the presence of a nitrogen carrier gas, BN instead of B was incorporated in graphene. This remarkable finding enabled us to grow a p-type graphene with a possible a band gap opening. This was corroborated by XPS and Raman spectroscopy studies of the material. This BN doped graphene material showed potential as a possible replacement of PEDOT:PSS as a hole transport material in OPVs. The BN doped graphene material can match the performance of PEDOT:PSS when the level of BN doping in graphene is increased.

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