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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.
1

Sulfuryl chloride manufacture and uses ...

Salls, Carroll Morgan, January 1924 (has links)
Thesis (Ph. D.)--Columbia University, 1925. / Vita. Description based on print version record.
2

The action of selenium oxychloride on some condensed aromatic compounds

Klein, Michael William, January 1924 (has links)
Thesis (Ph. D.)--University of Wisconsin--Madison, 1924. / Typescript. eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references.
3

The action of selenium oxychloride on certain unsaturated hydrocarbons

Frick, Carl Emmit. January 1923 (has links)
Thesis (Ph. D.)--University of Wisconsin--Madison, 1923. / Typescript. With this is bound: The action of selenium oxychloride upon ethylene, propylene, butylene and amylene / By Carl E. Frick. Reprinted from Journal of the American Chemical Society, Vol. XLV, no. 7 (July 1923), p. [1795]-1800. Includes bibliographical references.
4

Production And Characterization Of Magnesium Oxychloride Cement Based Polishing Bricks For Polishing Of Ceramic Tiles

Ozer, Muhammed Said 01 December 2008 (has links) (PDF)
Magnesium oxychloride cement (MOC) based grinding and polishing bricks developed for polishing of granite based ceramic tiles were produced and characterized. For surface grinding 46 and 180 grit size SiO2 powder embedded MOC based abrasive bricks / for polishing 600 and 1200 grit size SiC powder embedded MOC based abrasive bricks followed by neat (unreinforced) MOC pastes were applied on ceramic tiles. Three different neat MOC pastes depending on MgO/MgCl2 molar ratio in the paste e.g. 6/1, 7/1, and 8/1, were formed and evaluated. Grinding bricks were formed by adding 30 weight percentage, wt%, of both SiO2 powders. Polishing bricks were formed by adding 20, 25, and 30 wt% of both SiC powders. X-Ray diffraction analyses revealed that MOC F5 was the main crystalline phase in the neat MOC pastes. Additions of both SiO2 and SiC powders enhanced mechanical properties namely / compressive strength and abrasion resistance, chemical durability in water and polishing ability of MOC paste. More than 25 wt% addition of SiC powders had a tendency to decrease the compressive strength and water resistance of MOC paste. Polishing performance of abrasive bricks was evaluated in terms of mean surface roughness of ceramic tiles and abrasive brick consumption upon polishing. Scanning Electron Microscope examinations revealed the evidences of the reasons that 25 wt% SiC powder embedded abrasive bricks has the best qualifications in terms of abrasion resistance and polishing performance.
5

Controle da mancha preta dos citros via fungicida cúprico e validação da produção de frutos cítricos em área não livre da doença: estudo de caso / Control of black citrus with cooper fungicide and validation of citrus fruit production in non-free area of the disease: case study

Fonseca, Antonio Eduardo 14 November 2017 (has links)
Submitted by ANTONIO EDUARDO FONSECA null (eduardofonseca.tva@gmail.com) on 2018-01-08T18:25:55Z No. of bitstreams: 1 Tese Final 0801.pdf: 1442032 bytes, checksum: 89542ace4e746a273c5a088d6a6ec38c (MD5) / Rejected by Alexandra Maria Donadon Lusser Segali null (alexmar@fcav.unesp.br), reason: Solicitamos que realize as correções na submissão seguindo as orientações abaixo: Estão faltando a ficha catalográfica e o certificado de aprovação. Não há necessidade da informação da lombada (lateral da tese), no arquivo para a submissão. Agradecemos a compreensão. on 2018-01-09T09:24:23Z (GMT) / Submitted by ANTONIO EDUARDO FONSECA null (eduardofonseca.tva@gmail.com) on 2018-01-09T10:41:43Z No. of bitstreams: 1 Tese Final 0801 - Copia.pdf: 1659919 bytes, checksum: 2281654cd9e9b6101d7f5f0b6b736247 (MD5) / Approved for entry into archive by Alexandra Maria Donadon Lusser Segali null (alexmar@fcav.unesp.br) on 2018-01-09T12:07:20Z (GMT) No. of bitstreams: 1 fonseca_ae_dr_jabo.pdf: 1659919 bytes, checksum: 2281654cd9e9b6101d7f5f0b6b736247 (MD5) / Made available in DSpace on 2018-01-09T12:07:20Z (GMT). No. of bitstreams: 1 fonseca_ae_dr_jabo.pdf: 1659919 bytes, checksum: 2281654cd9e9b6101d7f5f0b6b736247 (MD5) Previous issue date: 2017-11-14 / A mancha preta dos citros (MPC) é uma doença que causa lesões em frutos e queda prematura, levando a prejuízos de produção e rejeição no mercado consumidor. O uso de fungicidas sistêmicos ainda é a principal alternativa de controle, no entanto, se depara com os principais problemas do seu uso excessivo como acúmulo de resíduos nos frutos, seleção de estirpes resistentes e toxicidade ambiental. A busca por um controle alternativo pode envolver a aplicação de fungicidas cúpricos isoladamente, em intervalos reduzidos, no período de suscetibilidade do patógeno. Sendo assim, o trabalho teve como objetivos verificar o controle de MPC mediante a aplicação de fungicida cúprico em intervalo de 15 dias em diferentes dosagens e a validação da produção de frutos em padrão de exportação tomando como referência estudo de caso em propriedade localizada no município de Estiva Gerbi/SP. O experimento foi instalado no município de Bebedouro/SP durante a safra 2014/15, em pomar comercial de variedade ‘Valência’. O delineamento experimental utilizado foi em blocos casualizados, com sete tratamentos. Foi adotado como referência o fungicida oxicloreto de cobre. Os tratamentos (em doses do produto comercial) avaliados foram: zero (testemunha), 37,5; 50; 75; 100 e 125 mL 100 L-1. Com vistas a análises comparativas adotou-se um tratamento adicional, constituído pelo convencionalmente empregado pela respectiva propriedade. Este tratamento foi composto pela aplicação do fungicida cúprico óxido cuproso e fungicida do grupo da estrobilurina. As aplicações foram realizadas em intervalos de catorze dias, iniciando em 2/3 pétalas caídas, perfazendo um total de 14 aplicações. Foram realizadas cinco avaliações, em intervalos de 30 dias, estendendo-se até novembro, quando foi realizada a colheita dos frutos. Foram avaliadas queda de frutos, incidência e severidade dos sintomas, área abaixo da curva de progresso da doença (AACPD) e produção. Para a validação da produção de frutos em padrão de exportação, foram coletados frutos de laranjeira ‘Folha Murcha’, ‘Westin’, ‘Rubi’, ‘Pera’ e ‘Valência’, em estádio fenológico F6, com auxílio de GPS de Agricultura de Precisão, modelo - SMS Mobile, que gerou pontos equitativamente. A cada ponto gerado foram coletados 25 frutos de plantas de laranjeira, identificados e embalados, dos quatro quadrantes das plantas. No laboratório de Fitossanidade, da Faculdade de Ciências Agrárias e Veterinárias – Campus Jaboticabal, os frutos foram lavados e colocados sob imersão em solução contendo o princípio ativo Etefom a 750 miligramas por litro. Após o tratamento, os frutos foram mantidos em ambiente controlado, calibrado à temperatura de 25ºC ±1ºC, por 28 dias, condições que favorecem a rápida expressão dos sintomas. Concluiu-se que as aplicações sequenciais e quinzenais de oxicloreto de cobre SC a 100 e 125 mL 100L-1, foram eficientes no controle de MPC. É possível a produção de frutos de laranjeiras doces sem sintomas de MPC, mesmo em áreas não indenes, quando da incorporação de práticas culturais adequadas, de forma contínua e racionalizada, associado ao manejo adequado de P. citricarpa. / The citrus black spot (MPC) is a disease that causes lesions in fruits and premature fall, leading to losses of production and rejection in the consumer market. The use of systemic fungicides is the main control alternative, however, it faces the main problems of its excessive use as accumulation of residues in the fruits, and environmental toxicity. The search for an alternative control can involve the application of copper fungicides isolated, at reduced intervals, during the period of susceptibility of the pathogen. Therefore, the objective of this study was to verify MPC control by means the application of copper fungicide in interval of 14 days in different dosages and the validation of fruit production in export pattern taking as reference a case study in property located in the municipality of Estiva Gerbi/SP. The experiment was installed in the Bebedouro/SP city during the 2014/15 harvest, in a commercial orchard of 'Valencia' variety. The experimental was a randomized block design with seven treatments. The fungicide copper oxychloride was used as reference. The treatments (in doses of commercial product) evaluated were: zero (control), 37.5; 50; 75; 100 and 125 mL 100 L-1. With a view to comparative analysis, an additional treatment was adopted, constituted by the conventionally employed by the respective property. This treatment was composed by the application of the fungicide cuprous oxide and fungicide of the strobilurin group. The applications were performed at intervals of fifteen days, starting in 2/3 fallen petals, making a total of 14 applications. Five evaluations were carried out at 30 day intervals, extending until November, when the fruits were harvested. Fruit drop, incidence and severity of symptoms, area below the disease progress curve (AACPD) and production. For the validation of the fruit production in export pattern, fruits of 'Folha Murcha', 'Westin', 'Rubi', 'Pera' and 'Valencia' orange were collected in Phenological stage F6, with the help GPS of Accuracy, template - SMS Mobile, which generated points equally. At each point generated 25 fruits of orange plants, identified and packaged, were collected from the four quadrants of the plants. In the Phytosanitary laboratory of the College of Agrarian and Veterinary Sciences - Campus Jaboticabal, the fruits were washed and placed under immersion in solution containing the active principle Etefom at 750 miligramas per liter. After the treatment, the fruits were kept in controlled environment, calibrated at 25ºC ± 1ºC, for 28 days, conditions that favor the rapid expression of symptoms. It was concluded that the sequential and biweekly applications of SC 100 copper oxychloride and 125 mL 100L-1, were efficient in controlling MPC. It is possible to produce sweet orange fruits without MPC symptoms, even in non-indene areas, when of incorporating adequate cultural practices, in a continuous and rationalized way, associated to the proper management of P. citricarpa.
6

Influência de fontes e doses de fungicidas cúpricos e estrobilurinas aplicadas em consonância com eventos chuvosos no controle da mancha preta dos citros / Influence of copper fungicides sources and rates and strobilurins fungicides applied in consonance of rain events in the citrus black spot control

Franco, Danilo [UNESP] 13 November 2017 (has links)
Submitted by DANILO FRANCO null (franco.danilo@gmail.com) on 2018-01-08T23:48:13Z No. of bitstreams: 1 Tese_Danilo_Franco.pdf: 1663923 bytes, checksum: 2d8e6e2bc505a1017e531d2fb608942f (MD5) / Approved for entry into archive by Alexandra Maria Donadon Lusser Segali null (alexmar@fcav.unesp.br) on 2018-01-09T09:37:21Z (GMT) No. of bitstreams: 1 franco_d_dr_jabo.pdf: 1663923 bytes, checksum: 2d8e6e2bc505a1017e531d2fb608942f (MD5) / Made available in DSpace on 2018-01-09T09:37:21Z (GMT). No. of bitstreams: 1 franco_d_dr_jabo.pdf: 1663923 bytes, checksum: 2d8e6e2bc505a1017e531d2fb608942f (MD5) Previous issue date: 2017-11-13 / Neste estudo, foram realizados três experimentos (E1, E2 e E3). Os dois primeiros experimentos (E1 e E2) referem-se a avaliações da eficiência dose-resposta dos fungicidas hidróxido de cobre (HC), oxicloreto de cobre (OC) e óxido cuproso (OCp), aplicados nos estádios F1 e F2, no controle de Phyllosticta citricarpa, agente causal da mancha preta dos citros (MPC). E, no terceiro experimento (E3), foi avaliada a influência da aplicação de piraclostrobina em consonância com eventos chuvosos, no controle da MPC. Em E1 e E2 os fungicidas e dosagens avaliadas foram (g de cobre metálico 100 L-1 de calda): HC (43,7; 35,0; e 26,2; OC (100,8; 90,7; e 68,0) e; OCp (90,0; 56,3; e 42,2). No experimento E1 foram utilizadas plantas de laranjeira ‘Pera’, sob condições naturais de infecção, em Olímpia/SP. Foi adotado o delineamento experimental de blocos ao acaso, com quatro repetições. Cada parcela foi constituída de 33 plantas. Os fungicidas foram aplicados mediante turbopulverizador e vazão de 135 mL de calda m-3 de copa. Posteriormente, em todos os tratamentos, a partir do estádio F4 foram realizadas quatro aplicações de azoxistrobina a 75 g de i.a. 2.000 L-1, em intervalo de 42 dias. Foram realizadas quatro avaliações mensais, de agosto a novembro, amostrando-se casualmente 100 frutos nas seis plantas centrais da parcela, determinando-se a incidência (I) e severidade dos sintomas mediante escala de notas. A partir dos dados de severidade dos sintomas foi determinado o índice de doença (ID). Com os dados de ID, ao longo do tempo, calculou-se a área abaixo da curva de progresso da doença (AACPD). Em E2 foram empregadas plantas de laranjeira ‘Pera‘, também em Olímpia/SP. Os tratamentos avaliados foram semelhantes aos anteriormente citados, sendo, porém, aplicados com pulverizador manual do tipo “De Vilbs”, com volume suficiente para cobertura uniforme dos frutos. Foi adotado o delineamento de blocos ao acaso, em arranjo fatorial 10 tratamentos, sendo nove combinações de fungicidas cúpricos e uma testemunha, sem fungicida) x 5 (épocas de inoculação) e 4 (repetições). Cada parcela foi constituída por 20 frutos previamente ensacados com papel semi-kraft, no estádio F1. Posteriormente, no estádio F4, procedeu-se remoção dos sacos de papel, seguido do tratamento dos frutos exclusivamente com fungicidas cúpricos. O tratamento dos frutos deu-se mediante sua imersão, durante x segundos, na calda fungicida acrescida de óleo mineral a x%. Posteriormente, após secagem da calda procedeu-se o reensacamento dos frutos. A seguir, em intervalo semanal, entre 0 a 28 dias após o tratamento, foi realizada inoculação mediante aspersão de suspensão contendo 104 conídios mL-1. Na avaliação, realizada quando da colheita da maturação dos frutos, foram determinados os valores de I e ID. O experimento E3 foi realizado em pomar comercial de laranjeira ‘Folha Murcha’, no município de Paraíso/SP. Inicialmente, nos estádios F1 e F2 foram realizadas duas aplicações de oxicloreto de cobre (90 g de cobre metálico 100 L-1 de calda). Os tratamentos avaliados foram: aplicação do fungicida piraclostrobina em intervalo de 14 dias entre si, na dose de 25 g 2000 L-1; aplicação de piraclostrobina, na dose de 75 g 2000L-1 após o primeiro evento de chuva ocorrido 14 dias após a última aplicação do tratamento; aplicação de piraclostrobina, na dose de 75 g 2000L-1 após o primeiro evento de chuva, ocorrido 35 dias após a última aplicação do tratamento; aplicação de piraclostrobina, com intervalo de 42 dias entre si nas doses de 50 e 75 g 2000L-1. Esses tratamentos foram comparados com o tratamento padrão de azoxistrobina, na dose de 75 g 2000L-1, aplicado em intervalo de 42 dias. Foi utilizado o delineamento de blocos casualizados, e cada parcela foi constituída por 66 plantas. As condições operacionais adotadas para aplicação dos fungicidas foram semelhantes às adotadas em E1, porém com 150 mL de calda m-3 de copa. Os critérios de avaliações foram semelhantes aos citados em E1, em intervalos mensais, de setembro a janeiro. Concluiu-se que os fungicidas HC, OC e OCp nas doses de 43,7, 90,7 e 56,3 g de cobre metálico 100 L-1, respectivamente, aplicados nos estádios F1 e F2, complementado por aplicações de azoxistrobina, foram igualmente eficientes no controle de MPC. A eficiência do efeito protetor dos fungicidas cúpricos foi constatada por pelo menos 28 dias após a sua aplicação. Porém, a maior eficiência dos fungicidas cúpricos deu-se quando da sua aplicação previamente à inoculação de P. citricarpa. Aplicações de piraclostrobina a 75 g de i.a. 2000L-1 em intervalo de no mínimo 14 dias entre eventos chuvosos resultaram em maior controle da doença, quando comparado aos demais intervalos e doses de piraclostrobina e a azoxistrobina, na dose de 75 g 2.000 L-1, em intervalo fixo de 42 dias, com consequente redução da incidência e severidade de sintomas de MPC. / In this study, three experiments were performed (E1, E2 and E3). The first two experiments refer to the rate-response efficiency of the fungicides copper hydroxide (HC), copper oxychloride (OC) and cuprous oxide (OCp) in the control of Phyllosticta citricarpa, causal agent of citrus black spot (CBS). And the third (E3) the influence of pyraclostrobin application was evaluated in consonance with rainy events. In E1 and E2 the evaluated rates were: HC (43.7; 35.0; and 26.2 g of metallic copper 100L-1); OC (100.8, 90.7, and 68.0 g of metallic copper 100L-1); OCp (90.0, 56.3, and 42.2 g of metallic copper 100L-1). The experiment (E1) was conducted under natural infection by P. citricarpa in 'Pera' sweet orange planted in Olímpia/SP. A randomized blocks design was used, with four replications. Each plot was represented by 33 plants. The fungicides were applied in stages F1 and F2 by turbosprayer and 135 ml m-3 of the tree canopy. Subsequently, in F4 stage, all treatments were treated with azoxystrobin at 75 g 2000 L-1, four times in a 42-day interval. Four monthly evaluations were performed, from August to November, evaluating 100 fruits to determining the incidence and symptoms severity. Data were used to determined area under disease progress curve (AUDPC). In E2, a 'Pera' sweet orange plants were used, also located in Olímpia/SP. The treatments evaluated were similar those previously in E1, but were applied by a manual "De Vilbs" sprayer, with sufficient volum for uniform fruit coverage. A randomized blocks design were used in a factorial arrangement of 10 treatments (9 copper fungicides treatments and one untreated check) x 5 (inoculation times) and 4 (replicates). Each plot was formed by 20 pre-bagged fruits with semi-kraft paper in the F1 stage. In the F4 stage the bags were removed and the fruits sprayed exclusively with copper fungicides. Subsequently, in a weekly interval from 0 to 28 days after application at inoculation with suspension spray containing 104 conidia mL-1 was performed. In the harvest time an evaluation was performed and the values of I and DI were determined. E3 was carried out in a commercial 'Folha Murcha' sweet orange orchard, in Paraíso/SP. Initially, in stages F1 and F2, two applications of copper oxychloride based on 90 g of metallic copper 100 L-1 were perfomed. The treatments evaluated were: application with 14 days fixed interval in the pyraclostrobin rate of 25 g 2000L-1; application of 75 g 2000L-1 after the first rain event occurred 14 days after the last fungicide application; application of 75 g 2000L-1 after the first rain event occurred 35 days after the last fungicide application; application with 42 days fixed interval of 50 and 75 g 2000L-1. These treatments were compared with the standard treatment with 42 days fixed interval of azoxystrobin at rate 75 g 2000L-1. A randomized blocks design was used with 66 plants per plot. The fungicides applications were similar that in E1, but with 150 mL m-3 of canopy volume. The evaluations were similar that in E1, in monthly intervals, from September to January, in the ten central plants per plots. It was concluded that the fungicides HC, OC and OCp in the rates of 43.7, 90.7 and 56.3 g of metallic copper 100 L-1, respectively, applied in stages F1 and F2, complemented by applications of azoxystrobin, were equally efficient to control CBS. The protective effect of the copper fungicides was maintained until 28 days after treatment. However, the best response was obtained when inoculating P. citricarpa immediately after copper fungicides treatment. The 75 g 2000L-1 of pyraclostrobin application after the first rainy event occurred at least 14 days from the last fungicide application resulted in a greater reduction in the incidence and severity of CBS symptoms.
7

Voltametrijske metode zasnovane na ugljeničnim elektrodama modifikovane kompozitima na bazi višezidnih ugljeničnih nanocevi i čestica bizmuta ili antimona za određivanje odabranih ciljnih analita / Voltammetric methods based on carbon electrodes modified with multi walled carbon nanotubes and bismuth and antimony particles based composites for determination of selected target analytes

Petrović Sandra 12 September 2019 (has links)
<p>Cilj ove doktorske disertacija&nbsp; bio je razvoj&nbsp; novih, osetljivih, selektivnih i ekonomski<br />isplativih&nbsp; voltametrijskih&nbsp; radnih&nbsp; elektroda&nbsp; za&nbsp; praćenje&nbsp; odabranih&nbsp; analita&nbsp; kako&nbsp; u<br />laboratorijskim tako i pri terenskim uslovima.&nbsp; Ispitivana je&nbsp; mogućnost primene&nbsp; ovih&nbsp; radnih&nbsp; elektroda&nbsp; primenom&nbsp; voltametrijskih&nbsp; metoda&nbsp; kako&nbsp; u&nbsp; model&nbsp; rastvorima&nbsp; tako&nbsp; i&nbsp; u&nbsp; pojedinim realnim sistemima. SW-ASV&nbsp; zasnovana&nbsp; na&nbsp; elektrodama&nbsp; od&nbsp; staklastog&nbsp; ugljenika&nbsp; povr&scaron;inski modifikovanim&nbsp; Bi-MWCNT&nbsp; i&nbsp; BiOCl-MWCNT&nbsp; je&nbsp; primenjena&nbsp; za&nbsp; određivanje&nbsp; jona&nbsp; Pb(II)&nbsp; i Cd(II)&nbsp; pri&nbsp; optimizovanim&nbsp; uslovima&nbsp; merenja.&nbsp; Određivanje&nbsp; ciljnih&nbsp; jona&nbsp; vr&scaron;eno&nbsp; je&nbsp; pri&nbsp; radnom potencijalu&nbsp; od&nbsp; -1,2&nbsp; V&nbsp; (izmeren&nbsp; u&nbsp; odnosu&nbsp; na&nbsp; zasićenu&nbsp; kalomelovu&nbsp; elektrodu)&nbsp; i&nbsp; vremenu<br />elektrodepozicije jona&nbsp; od 120 s. Sva merenja su izvr&scaron;ena u rastvoru acetatnog pufera čija je pH-vrednost iznosila&nbsp; 4,0. Primenjeni koncentracioni opseg ciljnih analita iznosio je&nbsp; od 5 do 50&nbsp; &mu;g&nbsp; dm <sup>-3</sup> .&nbsp; Primenom&nbsp; ovog&nbsp; tipa&nbsp; elektrode&nbsp; dobijene&nbsp; su&nbsp; vrednosti&nbsp; granice&nbsp; detekcije&nbsp; za&nbsp; jone Pb(II) i Cd(II) 0,57&nbsp; &mu;g dm <sup>-3 </sup>i 1,2 &mu;g dm<sup>-3</sup> , redom. Dobijena RSD iznosila je manje od 10% za oba&nbsp; jona.&nbsp; Ova&nbsp; metoda&nbsp; je&nbsp; primenjena&nbsp; i&nbsp; za&nbsp; određivanje&nbsp; ciljnih&nbsp; jona&nbsp; u&nbsp; realnom&nbsp; uzorku&nbsp; porne vode&nbsp; sedimenta&nbsp; a&nbsp; rezultati&nbsp; dobijeni&nbsp; optimizovanom&nbsp; voltametrijskom&nbsp; metodom&nbsp; su&nbsp; u&nbsp; dobroj saglasnosti sa rezultatima koji su dobijeni primenom komparativne GFAAS metode. Bizmut oksihlorid-vi&scaron;ezidne ugljenične nanocevi kompozitni materijal je primenjen za povr&scaron;insko&nbsp; modifikovanje&nbsp; elektrode&nbsp; od&nbsp; staklastog&nbsp; ugljenika&nbsp; za&nbsp; brzo&nbsp; i&nbsp; jednostavno voltametrijsko&nbsp; određivanje&nbsp; tragova&nbsp; Zn(II)-jona&nbsp; primenom&nbsp; SW-ASV&nbsp; metode.&nbsp; BiOClMWCNT/GCE je pokazala linearan analitički odgovor u&nbsp; osegu koncentracija od&nbsp; 2,50 do&nbsp; 80,0 &mu;g&nbsp; dm <sup>-3 </sup>sa dobijenom vredno&scaron;ću GD 0,75 &mu;g&nbsp; dm<sup>-3 </sup>pri akumulacionom vremenu od&nbsp; 120 s&nbsp; i potencijalu&nbsp; elektrodepozicije&nbsp; -1,40&nbsp; V&nbsp; u&nbsp; odnosu&nbsp; na&nbsp; ZKE.&nbsp; Merenja&nbsp; su&nbsp; vr&scaron;ena&nbsp; u&nbsp; acetatnom puferu pH 4,5. Dobijena RSD iznosila je 4,8 %. Upoređene su performanse novodizajnirane BiOCl-MWCNT/GCE elektrode&nbsp; i&nbsp; tradicionalne elektrode na bazi bizmut filma (BiF/GCE), MWCNT/GCE,&nbsp; BiF-MWCNT/GCE&nbsp; i&nbsp; nemodifikovane&nbsp; GC&nbsp; elektrode.&nbsp; Novodizajnirana elektroda je primenjena za&nbsp; detekciju&nbsp; i određivanje&nbsp; Zn(II)-jona&nbsp; u realnim&nbsp; uzorcima kao &scaron;to su<br />dijetetski&nbsp; suplement&nbsp; i&nbsp; pekarski&nbsp; kvasac.&nbsp; Dobijeni&nbsp; rezultati&nbsp; su&nbsp; uporedivi&nbsp; sa&nbsp; deklarisanom vredno&scaron;ću&nbsp; u&nbsp; slučaju&nbsp; dijetetskog&nbsp; suplementa&nbsp; a&nbsp; u&nbsp; slučaju&nbsp; pekarskog&nbsp; kvasca&nbsp; sa&nbsp; rezultatima dobijenih komparativnom FAAS .<br />Elektroda od ugljenične paste je povr&scaron;inski modifikovana pripremljenim kompozitom<br />koji je&nbsp; izgrađen od vi&scaron;ezidnih ugljeničnih nanocevi i čestica&nbsp; Sb<sub>2</sub>O<sub>3.</sub>&nbsp; Kompozitni&nbsp; materijal&nbsp; je okarakterisan&nbsp; primenom&nbsp; TEM,&nbsp; EDS&nbsp; i&nbsp; XRD&nbsp; mernih&nbsp; tehnika.&nbsp; Sb<sub>2</sub>O<sub>3</sub>-MWCNT/CPE&nbsp; je okarakterisana primenom ciklične voltametrije a merenja su vr&scaron;ena u rastvoru hlorovodonične kiseline&nbsp; (pH&nbsp; 2,0).&nbsp; Primenom&nbsp; SW-ASV&nbsp; metode&nbsp; ova&nbsp; radna&nbsp; elektroda&nbsp; je&nbsp; upotrebljena&nbsp; za određivanje&nbsp; jona Pb(II) i Cd(II)&nbsp; u&nbsp; koncentracionom opsegu 2,0-40,0&nbsp; &mu;g&nbsp; dm&nbsp; <sup>-3 </sup>za&nbsp; Pb(II)-jon&nbsp; i 2,0-40,0&nbsp; &mu;g&nbsp; dm <sup>-3</sup> za&nbsp; Cd(II)-jon&nbsp; pri&nbsp; čemu&nbsp; su&nbsp; dobijene&nbsp; dobre&nbsp; linearne&nbsp; zavisnosti&nbsp; za&nbsp; oba&nbsp; ciljna jona.&nbsp; Optimalna&nbsp; procedura&nbsp; uključuje&nbsp; primenu&nbsp; Sb2O3-MWCNT/CPE&nbsp; u&nbsp; 0,01&nbsp; mol dm <sup>-3</sup><br />hlorovodoničnoj kiselini uz vreme elektrodepozicije jona iz rastvora od 120&nbsp; s&nbsp; na&nbsp; potencijaluod&nbsp; -1,2&nbsp; V,&nbsp; pri&nbsp; čemu&nbsp; su&nbsp; dobijene&nbsp; vrednosti&nbsp; za&nbsp; GD&nbsp; 1,1&nbsp; &mu;g&nbsp; dm <sup>-3</sup> Cd(II)&nbsp; i&nbsp; 1,6&nbsp; &mu;g&nbsp; dm <sup>-3</sup> Pb(II). Optimizovana&nbsp; metoda&nbsp; zasnovana&nbsp; na&nbsp; ovom&nbsp; tipu&nbsp; voltametrijskog&nbsp; senzora&nbsp; je&nbsp; uspe&scaron;no primenjena&nbsp; za&nbsp; određivanje&nbsp; jona&nbsp; Cd(II)&nbsp; u&nbsp; obogaćenom&nbsp; uzorku&nbsp; česmenske&nbsp; vode,&nbsp; gde&nbsp; su&nbsp; se dobijene vrednosti u&nbsp; saglasnosti sa očekivanom. Elektroda od ugljenične paste povr&scaron;inski je&nbsp; modifikovana primenom&nbsp; Sb<sub>2</sub>O<sub>3</sub>-MWCNT nanokompozitnog&nbsp; materijala&nbsp; i&nbsp; primenjena&nbsp; za&nbsp; direktno&nbsp; voltametrijsko&nbsp; određivanje imidakloprida&nbsp; u&nbsp; model&nbsp; rastvorima.&nbsp; U&nbsp; cilju&nbsp; postizanja&nbsp; &scaron;to&nbsp; boljih&nbsp; analitičkih&nbsp; performansi optimizovani su eksperimentalni uslovi merenja kao &scaron;to su pH-vrednost rastvora pomoćnog elektrolita&nbsp; i&nbsp; kondicioniranje&nbsp; povr&scaron;ine&nbsp; voltametrijskog&nbsp; senzora.&nbsp; Kao&nbsp; optimalna&nbsp; pH-vrednost pomoćnog elektolita (Britton-Robinsonovog pufera) odabrana je pH 7,0, a ponavljanje ciklusa cikliranja najmanje 4 puta povoljno utiče na stabilnost&nbsp; voltametrijskih signala. Optimizovana metoda primenjena je za SW direktno katodno određivanje imidakloprida u koncentracionom intervalu od 1,41 do 32,77 &mu;g cm <sup>-3</sup> uz dobijeni korelacioni faktor od 0,9995. Na osnovu dobijenih rezultata može se zaključiti da su razvijene analitičke metode pre svega&nbsp; osetljive,&nbsp; selektivne,&nbsp; reproduktivne&nbsp; i&nbsp;&nbsp; jednostavne&nbsp; &scaron;to&nbsp; omogućava&nbsp; njihovu&nbsp; primenu&nbsp; za veliki broj uzoraka.&nbsp; Merenjima u model i realnim rastvorima dokazana je mogućnost njihove primene&nbsp; u&nbsp;&nbsp; komplikovanim&nbsp; matriksima,&nbsp; pri&nbsp; različitim&nbsp; pH&nbsp; vredostima&nbsp; pri&nbsp; čemu&nbsp; su&nbsp; dobijeni<br />rezultati koji su u saglasnosti sa rezultatima primenjenih komparativnih metoda. Naravno, za dobijanje&nbsp; reprezentativnih&nbsp; rezultata&nbsp; neohodno&nbsp; je&nbsp; izvr&scaron;iti&nbsp; optimizaciju&nbsp; uslova&nbsp; merenja&nbsp; &scaron;to podrazumeva sam odabir supstrat-elektrode, odabir povr&scaron;inskog modifikatora i optimizaciju eksperimentalnih uslova merenja.</p> / <p>The&nbsp; aim of this&nbsp; Ph.D. thesis&nbsp; was the development of new, sensitive, selective and economically&nbsp; viable&nbsp; voltametric&nbsp; working&nbsp; electrode&nbsp; for&nbsp; continuous&nbsp; monitoring&nbsp; of&nbsp; different target&nbsp; analytes.&nbsp; The&nbsp; use&nbsp; of&nbsp; these&nbsp; advantaged&nbsp; working&nbsp; electrodes&nbsp; was&nbsp; investigated&nbsp; using voltametric methods both in model solutions and in certain real systems.SW-ASV&nbsp; based on glassy carbon&nbsp; electrode surface modified with&nbsp; Bi- MWCNT and BiOCl-MWCNT&nbsp; were&nbsp; applied&nbsp; for&nbsp; determination&nbsp; of&nbsp; Pb(II)&nbsp; and&nbsp; Cd(II)&nbsp; ions.&nbsp; Voltametric determination&nbsp; of&nbsp; Pb(II)&nbsp; and&nbsp; Cd(II)&nbsp; ions&nbsp; was&nbsp; performed&nbsp; at&nbsp; working&nbsp; potential&nbsp; of&nbsp; -1.2&nbsp; V (measured against the saturated calomel electrode) and time of electrodeposition of 120 s. All measurements were performed in acetate buffer solution pH 4.0. Concentration range of targetanalites were&nbsp; 5-50 &mu;g&nbsp; dm -3 . Using this type of electrode,&nbsp; obtained&nbsp; detection limits for&nbsp; Pb(II) and Cd(II) ions&nbsp; were&nbsp; 0.57&nbsp; &mu;g&nbsp; dm -3 and 1.2&nbsp; &mu;g&nbsp; dm -3 , respectively, with RSD lower than 10%.This&nbsp; method&nbsp; was&nbsp; applied&nbsp; for&nbsp; target&nbsp; ions&nbsp; determination&nbsp; in&nbsp; sediment&nbsp; pore&nbsp; water&nbsp; sample,&nbsp; and obtained results are comparable with those who are obtained using GFAAS method. Bismuth oxychloride-multiwalled carbon nanotubes composite material was applied for&nbsp; surface&nbsp; modification&nbsp; of&nbsp; the&nbsp; glass-carbon&nbsp; electrode&nbsp; for&nbsp; quick&nbsp; and&nbsp; simple&nbsp; voltametric determination&nbsp; of&nbsp; Zn(II)&nbsp; ions&nbsp; using&nbsp; the&nbsp; SW-ASV&nbsp; method.&nbsp; BiOCl-MWCNT/GCE&nbsp; showed&nbsp; a linear&nbsp; analytical&nbsp; response&nbsp; in&nbsp; a&nbsp;&nbsp; concentration&nbsp; from&nbsp; 2.50&nbsp; to&nbsp; 80.0&nbsp; &mu;g&nbsp; dm -3 with&nbsp; a&nbsp; value&nbsp; of detection limit 0.75 &mu;g dm -3 at a acumulation time of 120 s and an electrodeposition potential of&nbsp; -1.40 V vs. saturated&nbsp; calomel electrode.&nbsp; Measurements were carried out in acetate buffer pH 4.5. The obtained&nbsp; value of the RSD&nbsp; was&nbsp; 4.8%. The performance of the newly designed BiOCl-MWCNT/GCE&nbsp; electrode,&nbsp; traditional&nbsp; bismuth-based&nbsp; electrode&nbsp; (BiF/GCE), MWCNT/GCE,&nbsp; BiF-MWCNT/GCE&nbsp; and&nbsp; unmodified&nbsp; GC&nbsp; electrodes&nbsp; were&nbsp; compared.&nbsp; The applied electrode shows very good electroanalytic properties when determining this target ion. Obtained results are in good agreement with declared value in case of dietetic suplement, and in the brewer&rsquo;s yeast sample results were comparable with FAAS results. Carbon&nbsp; paste&nbsp; electrode&nbsp; surface&nbsp; modified&nbsp; with&nbsp; new&nbsp; composite&nbsp; material&nbsp; based&nbsp; on multiwalled carbon nanotubes and&nbsp; Sb2O3&nbsp; particles. The composite is characterized by TEM, EDS and&nbsp; XRD measurment. Sb2O3- MWCNT/CPE was characterized by cyclic voltammetry and measurements were carried out in a&nbsp; hydrochloric acid&nbsp; solution&nbsp; (pH 2.0). Using the SWASV&nbsp; method,&nbsp; this&nbsp; working&nbsp; electrode&nbsp; was&nbsp; used&nbsp; to&nbsp; determine&nbsp; Pb(II),&nbsp; Cd(II)&nbsp; ions&nbsp; in&nbsp; the concentration range&nbsp; from&nbsp; 2.0&nbsp; to 40.0&nbsp; &mu;g dm -3 for Pb(II) and 2.0-40.0&nbsp; &mu;g dm -3 for Cd(II) ions. Newly&nbsp; designed&nbsp; sensor&nbsp; showed&nbsp; good&nbsp; linear&nbsp; dependences&nbsp; for&nbsp; both&nbsp; target&nbsp; ions.&nbsp; The&nbsp; most optimal&nbsp; procedure&nbsp; involving&nbsp; application&nbsp; of&nbsp; Sb2O3-MWCNT/CPE&nbsp; in&nbsp;&nbsp; .01&nbsp; mol&nbsp; dm -3 hydrochloric&nbsp; acid,&nbsp; with&nbsp; electroposition&nbsp; time&nbsp; of&nbsp; target&nbsp; ions&nbsp; 120&nbsp; s&nbsp; at&nbsp; a&nbsp; electrodeposition potential&nbsp; of&nbsp; -1.2&nbsp; V.&nbsp; Obtained&nbsp;&nbsp; values&nbsp; of&nbsp;&nbsp;&nbsp; LOD&nbsp; 1,1&nbsp; &mu;g&nbsp; dm -3 for&nbsp; Cd(II)&nbsp; and&nbsp; for&nbsp; 1,6&nbsp; &mu;g&nbsp; dm -3 Pb(II)&nbsp; ions.&nbsp; An&nbsp; optimized&nbsp; method&nbsp; based&nbsp; on&nbsp; this&nbsp; type&nbsp; of&nbsp; voltametric&nbsp; sensor&nbsp; has&nbsp; been successfully&nbsp; applied&nbsp; for&nbsp; determination&nbsp; of&nbsp; Cd(II)&nbsp; ion&nbsp; in&nbsp; a&nbsp; spiked&nbsp; tap&nbsp; water&nbsp; sample.&nbsp; Results obtained during this measurment were in tune with expected results. CPE&nbsp; was&nbsp; surface&nbsp; modified&nbsp; using&nbsp; Sb2O3-MWCNT&nbsp; nanocomposite&nbsp; material&nbsp; and tested&nbsp; for&nbsp; direct&nbsp; voltametric&nbsp; determination&nbsp; of&nbsp; imidacloprid&nbsp; in&nbsp; model&nbsp; solutions.&nbsp; In&nbsp; order&nbsp; to achieve the best analytical performance, experimental conditions of measurement such as the pH value of the supporting electrolyte and conditioning of the voltametric sensor surface havebeen&nbsp; optimized.&nbsp; As&nbsp; an&nbsp; optimum&nbsp; pH&nbsp; value&nbsp; of&nbsp; the&nbsp; supporting&nbsp; electrolyte&nbsp; (Britton-Robinson buffer), a pH 7.0 was selected, and the repeating cycles of the cycling process at least 4 times favorably&nbsp; influenced&nbsp; the&nbsp; stability&nbsp; of&nbsp; the&nbsp; voltametric&nbsp; signals.&nbsp; The&nbsp; optimized&nbsp; method&nbsp; was applied for the SW direct cathodic determination&nbsp; of&nbsp; imidacloprid in the concentration range from 1.41 to 32.77 &mu;g cm -3&nbsp; with obtained correlation factor of 0.9995. Based on results it can be concluded that developed analytical methods are sensitive, selective, reproducibile and simple, which can enable their application for various number of samples. Measurements in the model and real solutions have demonstrated the possibility of their&nbsp; application&nbsp; in&nbsp; complicated&nbsp; matrices,&nbsp; at&nbsp; different&nbsp; pH,&nbsp; whereby&nbsp; obtained&nbsp; results&nbsp; are&nbsp; in accordance&nbsp; with&nbsp; the&nbsp; results&nbsp; of&nbsp; the&nbsp; applied&nbsp; comparative&nbsp; methods.&nbsp; For&nbsp; obtainig&nbsp; of representative&nbsp; results&nbsp; it&nbsp; is&nbsp; necessary&nbsp; to&nbsp; optimize&nbsp; conditions&nbsp; of&nbsp; measurment&nbsp; which&nbsp; include: selection of substrat electrode, surface modifier and optimization of experimental condition.</p>

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