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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
91

Implementing the UN Action Programme for Combating the Illicit Trafficking in Small Arms and Light Weapons in All Its Aspects.

Clegg, E., Crowley, Michael J.A., Greene, Owen J., Meek, S., Powell, S. January 2001 (has links)
yes / Historically, UN conferences have been criticised for resulting more in compromises than in commitments to real change, which is also a charge that has been levelled against the UN Conference on the Illicit Trade in Small Arms and Light Weapons in All Its Aspects (UN Small Arms Conference). The consensus-based approach adopted throughout the negotiations had the advantage of binding all participating States to all aspects of the agreed Programme of Action (PoA), but it also ensured that it would be difficult to achieve a sufficiently rigorous and comprehensive agreement on all of the measures required to tackle the trafficking, proliferation and misuse of small arms and light weapons (SALW). Therefore, in spite of the efforts of many governments and NGOs, the UN Small Arms Conference did not agree sufficiently robust agreements in several areas. Nonetheless, it was a valuable and productive process. The resulting PoA includes a reasonably comprehensive set of key principles and commitments, which provide a basis for taking forward action at national, regional and global levels. The PoAwas agreed by all of the participating States, amounting to more than 100, and each are politically bound to adopt and implement it. Given that the UN Small Arms Conference was the first of its kind, its achievement in generating political will and momentum for efforts to control SALW is important. Although many of the commitments are weaker and less comprehensive than hoped for by many governments and organisations, it is significant that the PoAcontains at least some important commitments in all but two of the `core¿ issue areas raised by States. The two exceptions relate to transfers to non-State actors and to civilian trade, possession and use of SALW, restrictions which were strongly opposed by the USA. Equally, human rights related issues were noteworthy by their absence in the PoA. Whilst the process of reaching agreement began with a far-reaching draft PoA in December 2000 (A/Conf.192/L.4), most of the comments that were tabled on this text during the second Preparatory Committee in January 2001 came from countries that sought to weaken its commitments. The subsequent draft (A/Conf.192/L.4/Rev.1) was therefore weaker, with the result that progressive States faced an uphill task in seeking to strengthen its provisions. The next draft PoA emerged at the UN Small Arms Conference itself in the form of a third draft (A/Conf.192/L.5). Although still limited in a number of key areas ¿ such as export criteria and transparency ¿ this document went further than L.4/Rev.1 in a number of respects and included specific international commitments, including on brokering and tracing lines of supply. This, however, proved too ambitious an agenda for a small group of States and in the end the document that was adopted by consensus (A/Conf.192/L.5/Rev.1) represented a lower-level compromise. Despite the difficulties of agreeing the consensus-based PoA, the process culminating in the agreement was perhaps as important as the agreement itself. UN Small Arms Conference represented the first time that all UN Member States had met to discuss the illicit trade in SALW in all its aspects with a view to agreeing a comprehensive set of measures to address the problem. Although many of the commitments contained in the PoAare couched in equivocal language that will allow States to do as much or as little as they like, it is clear that the UN Small Arms Conference has contributed to a much better understanding, amongst all stakeholders, of the nature of the illicit trade in SALW and of the particular concerns and priorities of different countries and sub-regions. It is also clear that although the Programme of Action provides a set of minimum standards and commitments which all states should adopt, it also encourages further action from all States willing to adopt more stringent commitments and stronger programmes. There is a willingness among a number of States to build upon the PoAand take more concrete and far-reaching measures at national, sub-regional, regional and international levels, such as specific arrangements for tracing co-operation, or mechanisms to co-ordinate e fforts to improve stockpile security or weapons destruction. This briefing provides a critical assessment of key provisions in the UN Small Arms Conference PoA. Section 1 measures the overall outcomes of the conference against those that the Biting the Bullet (BtB) project proposed as optimal conclusions, and suggests ways to put the commitments contained in the PoA into practice. Section 2 assesses the implementation and follow-up commitments contained in the PoA, and identifies ways of promoting the implementation of Sections III and IV, as well as options for making the most of the Biennial Meetings of States and the Review Conference in 2006. Section 3 examines funding and resourcing possibilities for the PoA including identifying needs, mobilising resources and matching needs with resources. The final section of the briefing focuses on the way forward, and in particular on how implementation of the PoA could build on existing regional initiatives and develop common international approaches to controlling SALW proliferation, availability and misuse. It also examines how action to prevent and combat the illicit trade in SALW in all its aspects can be taken forward at sub-regional and regional levels in conjunction with all major stakeholders, including civil society, in the period leading up to the first Review Conference.
92

Research on heavy metals in roadside and evaluation of heir influence on the environment / Sunkiųjų metalų pakelėse tyrimai ir įtakos aplinkai vertinimas

Jankaitė, Audronė 04 December 2007 (has links)
Soil contamination with heavy metals is a problem of worldwide concern that is still unsolved. The analysis of the current methods of soil cleaning from heavy metals leads to conclusions that phytoremediation, i.e. soil decontamination by using plants, is one of the best methods. Although this method has not received a wide application yet and possibilities of its application are still being analysed, it is one of the most prospective soil cleaning methods due to low cost and a rather efficient cleaning of the upper surface of soil. Three kinds of Poaceae f. Species – Lolium perenne L., Poa pratensis L. and Festuca pratensis Huds. – have been chosen in this work for decontaminating soil from heavy metals. These plants were grown under artificial laboratory conditions in soil which was once and periodically contaminated with heavy metals. It was established that it is the Lolium perenne L. that most efficiently removes heavy metals and cleans soil. The results of experiments show that the selected grassy plants (perennial ryegrass, meadow-grass and fescue-grass) efficiently clean soil from heavy metals (copper, lead, manganese, zinc, nickel and chromium) when soil contains both low (0.5–120 mg/kg) and high (up to 6,850 mg/kg) concentrations of these metals. Since the perennial ryegrass absorbs the highest amount of heavy metals, the highest efficiency of soil cleaning is achieved using this plant, therefore, 80 % of the mixture of grassy plants was formed of the perennial... [to full text] / Dirvožemio tarša sunkiaisiais metalais visame pasaulyje aktuali problema iki šiol neturinti universalaus sprendimo. Išanalizavus šiuo metu dirvožemio valymui nuo sunkiųjų metalų naudojamus metodus, galima daryti išvadą, kad vienas iš tinkamiausių metodų yra fitoremediacija, t. y. dirvožemio valymas nuo teršalų panaudojant augalus. Šis metodas dar nėra plačiai taikomas ir jo taikymo galimybės dar tik tiriamos tačiau, tai vienas iš perspektyviausių dirvožemio valymo metodų dėl sąlyginai mažos kainos ir pakankamai efektyvaus paviršinio dirvožemio sluoksnio išvalymo. Atliktų eksperimentinių tyrimų rezultatai parodė, kad pasirinkta žolinė augalija – daugiametė svidrė, pievinė miglė ir tikrasis eraičinas efektyviai valo dirvožemį nuo sunkiųjų metalų (vario, švino, mangano, cinko, nikelio, chromo) tiek esant mažoms (0,5–120 mg/kg), tiek didelėms (iki 6850 mg/kg) jų koncentracijoms dirvožemyje. Kadangi daugiausiai sunkiųjų metalų iš dirvožemio sorbuoja svidrė, tai dirvožemio valymo efektyvumas naudojant šią žolinės augalijos rūšį yra efektyviausias ir sudarant žolinės augalijos mišinį 80  sudarė svidrė ir po 10  eraičinas bei miglė. Eksperimentų metu tirta, kaip sunkiųjų metalų mišinio koncentracijos kenkia hidrobiontams ir nustatyta, kad didinat sunkiųjų metalų mišinio koncentracijas (iki 0,198–5,12 g/l) jos tampa letalinėmis vaivorykštiniam upėtakiui, tuo pačiu ir kitiems vandens gyvūnams.Pagal tyrimų su vaivorykštiniais upėtakiais rezultatus nustatyta, kad stebimų... [toliau žr. visą tekstą]
93

Sunkiųjų metalų pakelėse tyrimai ir įtakos aplinkai vertinimas / Research on heavy metals in roadside and evaluation of their influence on the environment

Jankaitė, Audronė 04 December 2007 (has links)
Dirvožemio tarša sunkiaisiais metalais visame pasaulyje aktuali problema iki šiol neturinti universalaus sprendimo. Fitoremediacija – naujai atsirandanti ir daug žadanti technologija nestipriai užterštiems dirvožemiams valyti naudojant augalus. Šiame darbe dirvožemio valymui nuo sunkiųjų metalų pasirinktos trys žolinės augalijos rūšys – svidrė, miglė ir eraičinas, augintos modelinėmis laboratorinėmis sąlygomis vieną kartą ir periodiškai sunkiaisiais metalais teršiamuose dirvožemiuose. Nustatyta, kad geriausiai sunkiuosius metalus iš dirvožemio sorbuoja ir didžiausias dirvožemio valymo efektyvumas pasiekiamas naudojant svidrę. Augalijai sorbuojant sunkiuosius metalus iš dirvožemio dalis šių metalų (Cu, Cr, Zn, Pb, Mn, Ni) koncentruojasi žolinės augalijos šaknyse, tačiau didžioji dalis ten susikaupiančių metalų (iki 90 proc.) pereina į antžeminę augalo dalį. Didžiausios sunkiųjų metalų koncentracijos augale (iki 60 proc. ir daugiau) ir atitinkamai efektyviausias dirvožemio valymas nustatytas svidrės atveju, todėl sudarant mišinį didžiąją dalį (80 proc.) jame sudaro svidrė. Sunkiųjų metalų mišinys daro neigiamą įtaką vaivorykštinio upėtakio jauniklių fiziologiniams ir morfologiniams rodikliams, todėl didinat sunkiųjų metalų mišinio koncentracijas (iki 0,198–5,12 g/l) jos tampa letalinėmis vaivorykštiniams upėtakiams, tuo pačiu ir kitiems vandens gyvūnams. Pagal tyrimų su vaivorykštiniais upėtakiais rezultatus nustatyta, kad stebimų upėtakių, gyvenusių akvariume, užterštame 5,7... [toliau žr. visą tekstą] / Soil contamination with heavy metals is a problem of worldwide concern that is still unsolved. The analysis of the current methods of soil cleaning from heavy metals leads to conclusions that phytoremediation, i.e. soil decontamination by using plants, is one of the best methods. Although this method has not received a wide application yet and possibilities of its application are still being analysed, it is one of the most prospective soil cleaning methods due to low cost and a rather efficient cleaning of the upper surface of soil. Three kinds of Poaceae f. Species – Lolium perenne L., Poa pratensis L. and Festuca pratensis Huds. – have been chosen in this work for decontaminating soil from heavy metals. These plants were grown under artificial laboratory conditions in soil which was once and periodically contaminated with heavy metals. It was established that it is the Lolium perenne L. that most efficiently removes heavy metals and cleans soil. The results of experiments show that the selected grassy plants (perennial ryegrass, meadow-grass and fescue-grass) efficiently clean soil from heavy metals (copper, lead, manganese, zinc, nickel and chromium) when soil contains both low (0.5–120 mg/kg) and high (up to 6,850 mg/kg) concentrations of these metals. Since the perennial ryegrass absorbs the highest amount of heavy metals, the highest efficiency of soil cleaning is achieved using this plant, therefore, 80 % of the mixture of grassy plants was formed of the perennial... [to full text]
94

Molekularbiologische Untersuchungen zu zentralnervösen Alterungsprozessen der Reproduktionsfunktion in der weiblichen Ratte / Molecular Biological Analysis of Central Nervous Age-Related Processes of the Reproduction Functions in the Female Rat

Makhouly, Bassel 03 October 2002 (has links)
Die GABA-ergen Neurone als Teil des GnRH-Netzwerkes spielen eine Rolle bei den Veränderungen der altersabhängigen Prozesse der Reproduktionsfunktion. Um die Regulation der gonadalen Steroide auf die Expression von GAD in reproduktionsabhängigen Regionen zu untersuchen, wurde im ersten Teil der vorliegenden Arbeit das männliche Rattenmodell gewählt. Nach der Untersuchung des endokrinen Zustands der Tiere anhand der Radioimmunoassay-Methode (RIA) wurden die zellulären Gentranskripte der beiden Isoformen von GAD, GAD65 und GAD67, mittels der Methode der in situ Hybridisierung in der POA, im Nukleus suprachiasmaticus (SCN), im mediobasalen Hypothalamus (MBH) und im Gyrus dentatus bestimmt. In allen untersuchten Regionen konnte nach der Kastration und einer anschließenden dreiwöchigen Erholungszeit kein Effekt beobachtet werden. Die Administration von Estradiol bewirkt in der POA eine signifikante Erhöhung der Expression von GAD65 und GAD67 um nahezu 40%. In den restlichen Regionen konnte dagegen kein Effekt gemessen werden. Die Testosteronbehandlung zeigte eine negative Wirkung auf die Regulation nur von GAD67: Eine 30%-ige Abnahme in der POA und eine 15%-ige im SCN. Im Gegensatz dazu trat im MBH und im Gyrus dentatus eine Verminderung der Expression nur bei GAD65 auf. Aus den hier vorgestellten Ergebnissen kann folgendes abgeleitet werden: Testosteron und Estradiol regulieren in unterschiedlicher Weise die Expression von GAD und so wiederum die inhibitorische Funktion von GABA. Da in der SCN, im MBH und im Gyrus dentatus im Gegensatz zu Estradiol eine Testosteron-Wirkung gemessen wurde, existiert eine eigene androgene Regulation von GAD. Weil die Estradiol-Zugabe eine Zunahme der Expression von GAD bewirkte und dieser Effekt von einer Abnahme der LH-Konzentration im Serum der betroffenen Tiergruppe begleitet wurde, ist die These bestätigt, dass GABA mit ihren inhibitorischen Funktionen zur Übermittlung der positiven Rückkopplung von Estradiol auf die LH-Freisetzung auf der Ebene der POA und nicht auf der Ebene der Axone agiert. Im Gegensatz zu Estradiol kann eine Progesteronbehandlung bei persistent östrischen Ratten einen LH-Peak auslösen und somit den Östrus-Zyklus wieder in Gang bringen. Aufgrund dieser Tatsache wurde im zweiten Teil der vorliegenden Arbeit ein Tiermodell zur Untersuchung der molekularbiologischen altersabhängigen Veränderungen entwickelt. Dabei wurden drei Monate alte proöstrische Ratten (Y) und 12 Monate alte persistent östrische Ratten (MA) benutzt. Die MA-Ratten wurden mit Progesteron behandelt. Sowohl die MA-Ratten als auch die Y-Ratten wurden um 13 Uhr und um 17 Uhr getötet. Eine unbehandelte MA-Gruppe, deren Tiere um 10 Uhr getötet wurden, diente hier als Kontrollgruppe. Anhand der LH-Messung der untersuchten Gruppen wurde ein Kontrollwert (5 ng/ml LH) für die positive Reaktion der Tiere auf Progesteron (responding animals) festgestellt. Es konnte bei 44% der persistent östrischen Ratten ein erhöhter LH-Spiegel erfolgreich wieder erreicht werden. In den Gruppen dieses Modells entstand eine Analogie zwischen den Gruppen der behandelten MA-13-Uhr und Y-13-Uhr Tiere sowie zwischen den responding animals und den Y-17 Uhr-Tieren. Um aussagekräftige statistische Veränderungen entlang der hypothalamo-hypophysio-ovariellen Achse in individuellen Tieren zu erhalten, wurde die Taqman®-PCR und die quantitative, kompetitive RT-PCR eingesetzt. Dabei wurden die folgenden Gene untersucht: ER α und ER β, GnRH, GnRH-R, GAD65 und GAD67, sowie FSH-β. In der POA, Hypophyse und im Ovar wurde altersabhängigen Genexpression beobachtet: Eine signifikante Abnahme der Expression von ER β sowohl in der Gruppe responding animals als auch in deren analoger Gruppe wurde in der POA (34 %), Hypophyse (44 %) und im Ovar (um die 30 %) gemessen. In der Hypophyse verzeichneten die mRNA-Transkripte von ER α bei der Gruppe der behandelten mittelalten Ratten der 13 Uhr-Gruppe eine Zunahme von 55% und bei der 13-Uhr-Gruppe der jungen Ratten einen Anstieg von 153 %. Ebenso nehmen die mRNA-Konzentrationen von FSH-β sowohl bei den responding animals als auch bei deren analoger Gruppe in gleichem Masse (ungefähr 300 %) zu. Da die Veränderungen der Expression von ER β, ER α und FSH-β bei den zwei analogen Gruppen auftritt, ist zu vermuten, dass diese Gene altersabhängig expremiert und an der Zyklusregulation ursächlich beteiligt sind. Die restlichen Gene zeigten entlang der Achse keine altersrelevanten Veränderungen. Da ER β-Expressionsveränderungen in der POA, in der Hypophyse und im Ovar gemessen wurden, konnte der wichtigste Schluss der hier vorgestellten Untersuchungen gezogen werden, dass nämlich ER β für den Erhalt des Zyklus essentiell sein kann. In diesem Teil der vorliegenden Arbeit wurde ein Tiermodell zur molekular biologischen Untersuchung der altersabhängigen Veränderungen mit sehr zufriedenstellender Ausbeute zur Wiederherstellung des Östrus-Zyklus (44%) erfolgreich entwickelt. Dieses Modell ermöglichte darüber hinaus die Untersuchung einer relativ hohen Anzahl an Genen entlang der hypothalamo-hypophysio-ovariellen Achse.
95

Degradação do pesticida amicarbazona em meio aquoso pelo processo TiO2/UV irradiado por luz solar. / Degradation of the herbicide amicarbazone in aqueous solution by the solar irradiated TiO2-UV process.

D\'Avila, Alexandre Coelho da Silva 03 August 2012 (has links)
Os processos oxidativos avançados (POAs) têm sido apontados como alternativa eficiente para a degradação de poluentes recalcitrantes. Entre os POAs, a fotocatálise utilizando luz solar vem sendo muito estudada tendo em vista sua aplicação no tratamento de efluentes aquosos contendo pesticidas. No presente trabalho, estudou-se a degradação do herbicida amicarbazona (AMZ) por meio do processo TiO2/UV em um reator com coletores parabólicos compostos irradiados por luz solar. Os experimentos foram realizados segundo uma matriz Doehlert para o estudo da influência da concentração inicial de AMZ (20-100 mg L-1), da concentração de catalisador (0,1-1 g L-1) e do número de tubos expostos à luz solar (1-9). Amostras retiradas ao longo do tempo foram analisadas quanto às concentrações de AMZ e de carbono orgânico total (TOC). As medidas radiométricas realizadas indicaram que a radiação UVB-UVA correspondeu em média a ca. 4% da radiação solar total incidente entre 310-2800 nm; a actinometria de ferrioxalato indicou fluxo fotônico médio de 3,58×10-5 mol fótons m-2 s-1 para dias ensolarados típicos. O processo TiO2/UV mostrou-se eficiente para degradação do pesticida, que foi totalmente removido antes de 45 minutos de tratamento, para as seguintes condições: [AMZ]0=21,3 mg L-1; [TiO2]=0,5 g L-1; e 7 tubos. Contudo, nesse caso houve apenas ca. 24% de mineralização e na grande maioria dos casos os valores de TOC permaneceram praticamente constantes, o que indica a formação de sub-produtos recalcitrantes, cuja toxicidade e biodegradabilidade devem ser caracterizadas. A análise estatística dos resultados confirma os efeitos importantes da concentração inicial do pesticida e do número de tubos expostos (volume irradiado), cujo aumento permite compensar a menor incidência de radiação solar. Em alguns experimentos os resultados sugeriram que a degradação da AMZ foi favorecida pela maior concentração de TiO2. Na grande maioria dos casos os valores de ACM foram inferiores a 50 m2 kg-1, o que torna este parâmetro interessante para aumento de escala de processos fotocatalíticos irradiados por luz solar empregados no tratamento de efluentes aquosos contendo amicarbazona. / Advanced oxidative processes (AOP) have been considered as an efficient alternative for the degradation of recalcitrant pollutants. Photocatalysis using solar radiation has been studied for the treatment of wastewaters containing pesticides. In this work, the degradation of the herbicide amicarbazone (AMZ) by the TiO2/UV process was studied in a reactor equipped with compound parabolic collectors irradiated by solar light. The experiments were carried out according to a Doehlert matrix to study the effects AMZ initial concentration (20-100 mg L-1), catalyst concentration (0.1-1 g L-1), and number of tubes exposed to solar light (1-9). Samples were analyzed for AMZ and total organic carbon (TOC) concentrations. Radiometric measurements indicated that UVB-UVA radiation corresponded in average to about 4% of the solar radiation between 310-2800 nm; ferrioxalate actinometry resulted in an average photonic flux of 3.58×10-5 mol fótons m-2 s-1 for typical sunny days. The TiO2/UV process showed to be efficient for the degradation of the pesticide, which was completely removed before 45 minutes of treatment, for the following conditions: [AMZ]0=21.3 mg L-1; [TiO2]=0.5 g L-1; and 7 tubes. However, in this case only ca. 24% of mineralization was achieved, and in most cases TOC values remained practically constant, indicating the formation of recalcitrant by-products whose toxicity and biodegradility should be characterized. Statistical analysis of the results confirmed important effects of pesticide initial concentration and number of tubes exposed (irradiated volume), whose increase enables to compensate the lower incidence of solar radiation. Some experimental results suggested that AMZ degradation was favored by higher TiO2 concentrations. In most cases the values of ACM were lower than 50 m2 kg-1, in such a way that this parameter is interesting for scale-up of solar irradiated photocalytic processes used in the treatment of amicarbazone-containing wastewaters.
96

Processos de tratamento não convencionais para degradação do antibiótico sulfadiazina em meio aquoso. / Non-conventional treatment processes for the degradation of the antibiotic sulfadiazine in aqueous medium.

Acosta, Arlen Mabel Lastre 25 April 2016 (has links)
A presença de antibióticos no meio ambiente aquático tem causado crescente preocupação mundial. Além dos relatos de resistência de bactérias a antibióticos, essa classe de fármacos também pode causar efeitos tóxicos e atuar como perturbadores endócrinos em diversos organismos vivos e, possivelmente, em humanos. Dentre os antibióticos comumente usados destacam-se as sulfonamidas, detectadas em águas subterrâneas e superficiais. Os processos avançados de oxidação (POA) têm sido apontados como tecnologias eficientes para tratamento de poluentes recalcitrantes em diferentes matrizes aquosas. Dentre os POA, o processo foto-Fenton é uma alternativa para a degradação de compostos não biodegradáveis, incluindo fármacos. Uma vez que a principal limitação do processo é o intervalo de pH (2,5- 4,0), a reação pode ser vantajosamente conduzida empregando-se substâncias bio-orgânicas solúveis (BOS) como agentes complexantes de Fe3+ em condições ligeiramente ácidas (pH 5). Por sua vez, o emprego da energia ultrassônica tem sido menos estudado. Nesse contexto, o objetivo deste trabalho é estudar a degradação do antibiótico sulfadiazina (SDZ) por meio do processo foto-Fenton na presença de substâncias bio-orgânicas solúveis (UVvis/ Fe3+/H2O2/BOS) e do processo de cavitação por meio de ultrassom (US). Os resultados obtidos mostram que a sulfadiazina é eficientemente degradada por ultrassom de alta frequência. As maiores porcentagens e taxas de remoção são obtidas usando menor frequência de operação (580 kHz), maior potência dissipada e em pH ligeiramente ácido (melhor condição: pH 5,5). Além disso, a reação de Fenton, combinada com o tratamento US, melhorou notavelmente a degradação da SDZ, particularmente quando quantidades extras de H2O2 foram adicionadas ao sistema. Por sua vez, o uso de BOS como aditivos no processo foto-Fenton apresenta influência marcante na fotodegradação da SDZ em condições ligeiramente ácidas (pH 5). Os BOS podem estabilizar espécies de ferro em solução aquosa em pH próximos ao neutro, o que constitui uma propriedade de grande interesse. Sob as condições estudadas, o BOS CVT230 foi mais eficiente do que FORSUD, provavelmente devido às diferenças nos grupos funcionais presentes na composição destas substâncias. Finalmente, foram calculados os indicadores de consumo de energia elétrica por ordem de grandeza (EEO) para o processo de ultrassom (1572 kW h m-3 ordem-1) e área do coletor por ordem de grandeza (ACO) para o processo foto-Fenton (8,07 m2 m-3 ordem-1). / The potential impacts of antibiotic residues in the environment have become an emerging concern during recent years due to their relation with the development of resistant bacteria, and in some cases to their ability to cause toxic and endocrine disrupting effects in humans and other living organisms. Highlighted among the commonly used antibiotics are the sulfonamides, detected in groundwater and surface water. Advanced oxidation processes (AOP) might constitute an important alternative to deal with pharmaceuticals degradation. Among them, the photo-Fenton process has been widely used. One of its major drawbacks is the highly acidic pH needed (2,5-4,0) to avoid the formation of photochemically inactive iron oxides and hydroxides. The ability of soluble bio-organic substances (SBO) to complex metal cations such as iron is useful for the development of photo-Fenton at mild acidic conditions (pH 5). In turn, the use of ultrasonic energy has been less studied. In this context, the aim of this work is to study the degradation of the antibiotic sulfadiazine (SDZ) by the photo-Fenton process in the presence of soluble bio-organic substances (UV-vis/Fe3+/H2O2/SBO) and by ultrasonic cavitation (US). The results confirm that SDZ is effectively degraded by highfrequency ultrasound. Higher SDZ percent removals and removal rates were observed for the lowest operating frequency (580 kHz), higher dissipated power, and in slightly acidic solution (pH 5.5). On the other hand, SDZ degradation is highly improved in the case of the US/ Fe(II)/H2O2 system. The use of the SBO as Fenton additives in turn has a remarkable influence in SDZ photodegradation at slightly acid conditions (pH 5). This could be ascertained to the complexation of iron by the SBO, hence maintained in the reaction medium as a photoactive species. Under the studied conditions, the BOS CVT230 was more efficient than FORSUD, probably due to differences in the functional groups present in the composition of these substances. Finally, the figures-of merit electrical energy per order (EEO) and collector area per order (ACO) were calculated for the ultrasound (1572 kW h m-3 ordem-1) and photo-Fenton (8,07 m2 m-3 ordem-1) processes respectively.
97

From reclamation to restoration: native grass species for revegetation in northeast British Columbia

Huff, Valerie 04 January 2010 (has links)
Grasses are widely used in revegetation to control erosion, build soil and maintain habitat. In northeast British Columbia, non-native grass species are commonly seeded to reclaim industrially disturbed sites. Widespread concern about degradation of biodiversity and key ecological processes has led to increasing value placed on native species and management practices leading to a more resilient landscape. I undertook this study to fill the restoration knowledge gap relating to native grasses in northeast BC. I did an extensive inventory of grasses on 217 sites in 2007, 2008 and 2009. Functional traits were measured in the field and in a greenhouse growth experiment. I found ninety-nine grass species occuring in the region, 70% of which are native. The number, proportion and extent of non-native grasses are increasing and four of these – Poa pratensis, Festuca rubra, Bromus inermis, and Phleum pratense represented almost a quarter of all occurrences. Several native species were common throughout the region: Calamagrostis canadensis, Leymus innovatus, Elymus trachycaulus, Poa palustris and Agrostis scabra. Other native species, including Festuca altaica, Koeleria macrantha, Pascopyrum smithii, and Schizachne purpurascens, strongly favoured intact habitats. Elevation, soil moisture regime, proportion of bare ground, and land use were significant factors related to local grass species composition and abundance. Agrostis scabra, Alopecurus aequalis, Beckmannia syzigachne, Bromus ciliatus, Cinna latifolia, Deschampsia cespitosa, Elymus alaskanus, Elymus trachycaulus, Festuca saximontana and Hordeum jubatum grew commonly on severely damaged well sites. Field measurements for Specific Leaf Area (SLA) and Leaf Dry Matter Content (LDMC) of 11 species showed an inverse correlation. Bromus ciliatus, Bromus pumpellianus, and Elymus trachycaulus had high SLA/low LDMC linked to rapid growth, whereas Festuca altaica, Deschampsia cespitosa, and Calamagrostis stricta had low SLA/high LDMC linked to slow growth and persistence. In the greenhouse experiment, Poa palustris, Cinna latifolia and Bromus ciliatus produced the most overall biomass and Pascopyrum smithii and Poa palustris produced the greatest aboveground biomass. Calamagrostis stricta, Poa palustris, Elymus glaucus, Leymus innovatus and Pascopyrum smithii exhibited clonal growth. Beckmannia syzigachne, Bromus ciliatus Cinna latifolia produced viable seed during the 135-day experiment. Considering all attributes five native species, Calamagrostis canadensis, Elymus trachycaulus, Poa palustris, Leymus innovatus, and Agrostis scabra are recommended for general restoration use in northeast B.C. Other native species show promise when matched to particular site conditions, including Alopecurus aequalis, Arctagrostis latifolia, Beckmannia syzigachne, Bromus ciliatus, Calamagrostis stricta, Cinna latifolia, Deschampsia cespitosa, Elymus glaucus, Festuca saximontana, Glyceria striata, Hordeum jubatum, Koeleria macrantha, Pascopyrum smithii, Poa alpina, Schizachne purpurascens and Trisetum spicatum. This information will be valuable to land managers interested in moving beyond reclamation to ecological restoration of sites disturbed by oil and gas development. Developing practices that are environmentally sound and socially acceptable requires ongoing botanical inventory. Plant traits may be useful in matching species to site conditions and restoration goals. Policy recommendations include phasing in of requirements to use native seed while restricting the use of agronomic species, promoting natural colonization, and supporting a native seed industry.
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Utilizando programa??o orientada a aspectos no projeto de sistemas hardware desenvolvidos com SystemC

Medeiros, Sergio Queiroz de 03 March 2006 (has links)
Made available in DSpace on 2014-12-17T15:48:06Z (GMT). No. of bitstreams: 1 SergioQM.pdf: 363127 bytes, checksum: 7b8fb995a67b3e514e8b774e59124df3 (MD5) Previous issue date: 2006-03-03 / New programming language paradigms have commonly been tested and eventually incorporated into hardware description languages. Recently, aspect-oriented programming (AOP) has shown successful in improving the modularity of object-oriented and structured languages such Java, C++ and C. Thus, one can expect that, using AOP, one can improve the understanding of the hardware systems under design, as well as make its components more reusable and easier to maintain. We apply AOP in applications developed using the SystemC library. Several examples will be presented illustrating how to combine AOP and SystemC. During the presentation of these examples, the benefits of this new approach will also be discussed / Novos paradigmas de linguagens de programa??o v?em sendo comumente testados e geralmente s?o incorporados depois por linguagens de descri??o de hardware. Recentemente, a programa??o orientada a aspectos (POA) provou ser ?til na tentativa de melhorar a modularidade de linguagens estruturadas e orientadas a objeto tais como Java, C++ e C. Diante de tal fato, podemos esperar que o uso de POA pode melhorar o entendimento de sistemas hardware que est?o sendo projetados, bem como tornar seus componentes mais reus?veis e f?ceis de manter. Iremos abordar ent?o o uso de POA em aplica??es desenvolvidas utilizando a biblioteca SystemC. Ser?o apresentados v?rios exemplos que ilustram o uso de POA juntamente com SystemC, mostrando alternativas e discutindo os seus benef?cios
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Extensões do metamodelo KDM para apoiar modernizações orientadas a aspectos de sistemas legados

Santos, Bruno Marinho 21 October 2014 (has links)
Made available in DSpace on 2016-06-02T19:06:20Z (GMT). No. of bitstreams: 1 6500.pdf: 5345644 bytes, checksum: e886844b4ba61e58d704a8babf113721 (MD5) Previous issue date: 2014-10-21 / Maintaining legacy systems is a complex and expensive activity for many companies. A recently proposal to solve this problem is Architecture-Driven Modernization (ADM), proposed by Object Management Group (OMG). The ADM consists of a set of concepts and standard metamodels that support systems modernization using models. The Knowledge Discovery Metamodel (KDM) is the main metamodel of ADM, it can represent many artifacts of a legacy system, such as source code, architecture, user interface, configuration files and business process. In general, legacy systems have crosscutting concerns, it can show source code problems like tangling and scattering, and it raises the maintenance costs. The aspect orientation is an alternative to improve crosscutting concerns modularization. Thus, in this dissertation is presented the term Aspect Oriented Modernization that uses the aspect oriented concepts in the ADM context. This modernization process consists in modularize legacy systems with aspects represented in model level. To achieve this goal, in this work were performed a lightweight and a heavyweight extension in the KDM metamodel, to analyze which one would present a better performance if used by Modernization Engineers. The evaluation of these extensions was performed by a case study that considered the modernization with aspects of a small-sized system. To evaluate the case study in both extensions, a set of comparison criteria were created to support the software engineers in choosing the best extension mechanism, according to their needs. In the context of this dissertation an experimental study were developed that aimed reproducing the scenarios that the modernization engineers had to perform maintenances and developing new refactorings in a aspect oriented KDM model. The experiment data considered the development time of the activities and the found number of errors. Finally, it was noticed that the extension mechanism to be choose will depend on the context that it will be applied, however, considering the approach studied here the best extension mechanism is the heavyweight one. / Manter sistemas legados é uma atividade complexa e onerosa para muitas empresas. Uma proposta recente para esse problema é a Modernização Dirigida à Arquitetura (Architecture-Driven Modernization - ADM), proposta pela OMG (Object Management Group). A ADM consiste em um conjunto de princípios e metamodelos padrões que apoiam a modernização de sistemas utilizando modelos. O Knowledge Discovery Metamodel (KDM) é o principal metamodelo da ADM, podendo representar diversos artefatos de um sistema, como código-fonte, arquitetura, interface de usuário, arquivos de configuração e processos de negócio. Em geral, sistemas legados possuem interesses transversais, apresentando problemas de entrelaçamento e espalhamento de código, o que eleva os custos de manutenção. A orientação a aspectos é uma alternativa para melhorar a modularização de interesses transversais. Mediante isso, neste trabalho é apresentado o termo Modernização Orientada a Aspectos que utiliza os conceitos da orientação a aspectos na ADM. Essa modernização consiste em remodularizar sistemas legados utilizando aspectos representados em nível de modelo. Para atingir esse objetivo, foi realizada uma extensão leve e outra pesada do metamodelo KDM, para analisar em qual das duas o desempenho dos engenheiros de modernização seria melhor. Para fazer a avaliação das extensões, foi realizado um estudo de caso levando em consideração a modernização com aspectos em um sistema de pequeno porte. Com o objetivo de avaliar o estudo de caso usando as duas extensões, foram desenvolvidos critérios de comparação que auxiliassem os engenheiros de software a escolher qual dos dois mecanismos de extensão utilizar em seu projeto. Foi feito também um estudo experimental que buscou reproduzir os cenários em que engenheiros de modernização tivessem que realizar manutenções e desenvolver novas refatorações em um modelo KDM orientado a aspectos. Os dados do experimento foram avaliados em relação ao tempo de desenvolvimento das atividades e quantidade de erros encontrados. Por fim, percebeu-se que o mecanismo de extensão a ser utilizado vai depender do contexto em que ele será aplicado, mas, para o domínio aqui estudado a extensão que melhor atendeu aos requisitos foi a pesada.
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Degradação do pesticida amicarbazona em meio aquoso pelo processo TiO2/UV irradiado por luz solar. / Degradation of the herbicide amicarbazone in aqueous solution by the solar irradiated TiO2-UV process.

Alexandre Coelho da Silva D\'Avila 03 August 2012 (has links)
Os processos oxidativos avançados (POAs) têm sido apontados como alternativa eficiente para a degradação de poluentes recalcitrantes. Entre os POAs, a fotocatálise utilizando luz solar vem sendo muito estudada tendo em vista sua aplicação no tratamento de efluentes aquosos contendo pesticidas. No presente trabalho, estudou-se a degradação do herbicida amicarbazona (AMZ) por meio do processo TiO2/UV em um reator com coletores parabólicos compostos irradiados por luz solar. Os experimentos foram realizados segundo uma matriz Doehlert para o estudo da influência da concentração inicial de AMZ (20-100 mg L-1), da concentração de catalisador (0,1-1 g L-1) e do número de tubos expostos à luz solar (1-9). Amostras retiradas ao longo do tempo foram analisadas quanto às concentrações de AMZ e de carbono orgânico total (TOC). As medidas radiométricas realizadas indicaram que a radiação UVB-UVA correspondeu em média a ca. 4% da radiação solar total incidente entre 310-2800 nm; a actinometria de ferrioxalato indicou fluxo fotônico médio de 3,58×10-5 mol fótons m-2 s-1 para dias ensolarados típicos. O processo TiO2/UV mostrou-se eficiente para degradação do pesticida, que foi totalmente removido antes de 45 minutos de tratamento, para as seguintes condições: [AMZ]0=21,3 mg L-1; [TiO2]=0,5 g L-1; e 7 tubos. Contudo, nesse caso houve apenas ca. 24% de mineralização e na grande maioria dos casos os valores de TOC permaneceram praticamente constantes, o que indica a formação de sub-produtos recalcitrantes, cuja toxicidade e biodegradabilidade devem ser caracterizadas. A análise estatística dos resultados confirma os efeitos importantes da concentração inicial do pesticida e do número de tubos expostos (volume irradiado), cujo aumento permite compensar a menor incidência de radiação solar. Em alguns experimentos os resultados sugeriram que a degradação da AMZ foi favorecida pela maior concentração de TiO2. Na grande maioria dos casos os valores de ACM foram inferiores a 50 m2 kg-1, o que torna este parâmetro interessante para aumento de escala de processos fotocatalíticos irradiados por luz solar empregados no tratamento de efluentes aquosos contendo amicarbazona. / Advanced oxidative processes (AOP) have been considered as an efficient alternative for the degradation of recalcitrant pollutants. Photocatalysis using solar radiation has been studied for the treatment of wastewaters containing pesticides. In this work, the degradation of the herbicide amicarbazone (AMZ) by the TiO2/UV process was studied in a reactor equipped with compound parabolic collectors irradiated by solar light. The experiments were carried out according to a Doehlert matrix to study the effects AMZ initial concentration (20-100 mg L-1), catalyst concentration (0.1-1 g L-1), and number of tubes exposed to solar light (1-9). Samples were analyzed for AMZ and total organic carbon (TOC) concentrations. Radiometric measurements indicated that UVB-UVA radiation corresponded in average to about 4% of the solar radiation between 310-2800 nm; ferrioxalate actinometry resulted in an average photonic flux of 3.58×10-5 mol fótons m-2 s-1 for typical sunny days. The TiO2/UV process showed to be efficient for the degradation of the pesticide, which was completely removed before 45 minutes of treatment, for the following conditions: [AMZ]0=21.3 mg L-1; [TiO2]=0.5 g L-1; and 7 tubes. However, in this case only ca. 24% of mineralization was achieved, and in most cases TOC values remained practically constant, indicating the formation of recalcitrant by-products whose toxicity and biodegradility should be characterized. Statistical analysis of the results confirmed important effects of pesticide initial concentration and number of tubes exposed (irradiated volume), whose increase enables to compensate the lower incidence of solar radiation. Some experimental results suggested that AMZ degradation was favored by higher TiO2 concentrations. In most cases the values of ACM were lower than 50 m2 kg-1, in such a way that this parameter is interesting for scale-up of solar irradiated photocalytic processes used in the treatment of amicarbazone-containing wastewaters.

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