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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

A TLAPALIZQUIXOCHITL TREE

Mahonski, Christopher 12 May 2009 (has links)
This writing was done in correlation to my thesis show, The Void, the Coach and the Future.
2

Biosorpcija jona teških metala iz vode izluženim rezancima šećerne repe / Biosorption of heavy metal ions from water by sugar beet shreds

Kukić Dragana 18 November 2016 (has links)
<p>Cilj ove doktorske disertacije je bio da se ispita mogućnost primene izluţenih rezanaca &scaron;ećerne repe i njihovih tretiranih oblika, nastalih u procesu proizvodnje bioetanola, kao biosorbenata za uklanjanje jona te&scaron;kih metala iz vode. U okviru eksperimenata, u laboratorijskim uslovima izvedeni su predtretman i hidroliza izluženih rezanaca kako bi se dobili tretirani oblici, a zatim je izvr&scaron;ena karakterizacija adsorbenata, ispitane njihove adsorpcione sposobnosti, utvrđeni najbolji uslovi za njihovu primenu i ispitana mogućnost njihove vi&scaron;estruke primene u obradi vode.<br />U okviru karakterizacije materijala određen je njihov sastav, specifiĉna povr&scaron;ina i poroznost, ispitana povr&scaron;ina primenom FTIR i EDS metode i kvantifikovana količina pojedinih funkcionalnih grupa prisutnih na povr&scaron;ini primenom Boehm-ove titracije. Na osnovu FTIR metode pre i posle adsoprcije utvrđeno je koje grupe učestvuju u vezivanju jona metala.<br />Ispitan je i uticaj razliĉitih parametara na adsorpciju (vreme kontakta adsorbenta i adsorbata, veličina čestice, pH, temperatura, primenjena doza adsorbenta, jonska jačina, su&scaron;enje) radi utvrđivanja najboljih uslova za maksimalnu efikasnost.<br />Kako bi se stekao bolji uvid u sam proces adsorpcije jona na povr&scaron;inu adsorbenata, na eksperimentalne podatke primenjeni su različiti modeli adsorpcionih izotermi, a mehanizam vezivanja je detaljnije razmotren primenom kinetiĉkih modela. Primenom termodinamičkih modela utvrđena je priroda procesa.<br />Radi vi&scaron;estruke primene ovih ekolo&scaron;kih biosorbenata ispitana je i mogućnost regeneracije materijala razliĉitim kiselinama kao desorbensima i utvrđeno optimalno vreme desorpcije. Ispitana je primena kroz vi&scaron;e uzastopnih ciklusa adsorpcija &ndash; desropcija. Rezultati su pokazali da ispitani materijali imaju zadovoljavajući adsorpcioni kapacitet, ali da se mogu primenjivati i vlažni, odmah nakon procesa ekstrakcije &scaron;ećera, depektinacije i hidrolize, bez utro&scaron;ka energije za su&scaron;enje. Pored toga, utvrđeno je da se mogu regenerisati i koristiti uspe&scaron;no vi&scaron;e puta, &scaron;to otvara mogućnost za njihovu primenu u praksi.</p> / <p>The aim of this PhD thesis was to investigate the possibility of usage of sugar beet shreds and their treated forms from the bioethanol production for removal of heavy metal ions from water. In the context of experiments, pretreatment and hydrolysis of sugar beet shreds were performed in order to obtain treated forms. The characterization of biosorbents was conducted and their adsorption capacity was investigated. Also, the optimal conditions for their implementation and the possibility of their multiple applications for water treatment were determined.<br />Within the characterization of materials their composition, specific surface area and porosity were determined. The surface of biosorbents was investigated by using FTIR and EDS methods. The amount of the functional groups present on the surface was quantified by Boehm&#39;s titration. On the basis of the FTIR method before and after adsorption it was determined which functional groups participate in the binding process.<br />The influence of various parameters on the adsorption (contact time of the adsorbent and adsorbate, particle size, pH, temperature, adsorbent dose, ionic strength, drying process) were examined in order to determine the best conditions for maximum efficiency.<br />For better insight into the process of adsorption of ions on the surface of the adsorbents, different models of adsorption isotherms were applied to experimental data. Mechanism of adsorption was determined by applying different kinetic models. The nature of the process was investigated by determining thermodynamic parameters.<br />The multiple applications of these eco-friendly biosorbents was examined by regeneration investigation. The optimal time of desorption was determined and different acids were used for regeneration study. The multiple cycles adsorption &ndash; desorption was also conducted.<br />The results showed that the investigated materials have a satisfactory adsorption capacity. They can also be applied wet, immediately after the process of sugar extraction, depectination and hydrolysis, without the energy consumption for drying. In addition, it was found that they can be regenerated and successfully used several times. This opens up the possibility for their practical application.</p>
3

Investigating Kracauerian cinematic realism through film practice and criticism: Life-world series (2017) and selected films of Lino Brocka

Gutierrez III, Jose 27 August 2018 (has links)
This dissertation is an investigation on the realist film theory of Siegfried Kracauer. It was principally conducted through film practice as exemplified by the ten short films that compose the omnibus film project, Life-world Series (dir. Joni Gutierrez, 2017, 118 minutes). To supplement the study's examination of Kracauerian cinematic realism (KCR), film criticism of selected works of Lino Brocka was also accomplished. The methodology involved three components: (1) research-based production of Life-world Series; (2) textual analyses of the said film collection and selected Brocka films; and (3) meta-analysis of the scholarly criticism on the Brocka film. This dissertation is the first to use film-making practice which was a part of the research project and devised to investigate KCR, which avows that the cinematic experience of physical reality as an object of contemplation fosters an intuitive understanding of the Lebenswelt (life-world) and, in turn, brings about the redemptive potential of film vis-à-vis the modern condition. The emergent design of Life-world Series opened the study to a wide range of possibilities that it could not have encountered if it limited itself to applying a particular theory as a framework in doing film criticism of pre-existing works. This project - through both its film practice and criticism components - is an interweaving of key notions from Husserlian phenomenology and the seven KCR tropes identified in the study, namely: (1) the quotidian; (2) the transient; (3) the refuse; (4) the fortuitous; (5) the indeterminate; (6) the flow of life; and (7) the spiritual life itself. The phenomenological engagement of this investigation has provided opportunities for expanding the inventory of KCR tropes, to conceivably include characteristics of the Lebenswelt which form part of the project's overall findings; that is, the life-world as: (1) expansive; (2) multi-layered; (3) flowing; (4) in the process of becoming; (5) resonantly intersubjective; (6) a thing of beauty; (7) relating to essences; (8) cyclical; (9) transcendent; (10) meaning-laden; (11) fragmented; and (12) malleable. The dissertation explicates how its phenomenological approach in inspecting KCR led to the construction of a prospective model of cinematic realism - the integrated quadrant model of Kracauerian cinematic realism (IQMKCR) - and finally, determines the implications and prospects of using film practice as an instrument in interrogating KCR.
4

Bistrenje soka šećerne repe primenom alternativnih koagulanata i flokulanata / Sugar beet juice clarification by means of alternative coagulants and flocculants

Kuljanin Tatjana 04 February 2008 (has links)
<p>Pri proizvodnji kvalitetnog belog konzumnog &scaron;ećera iz &scaron;ećerne repe, srećemo se sa problemom prisustva makromolekularnih jedinjenja u soku &scaron;ećerne repe koja su &scaron;tetna pa ih je neophodno odstraniti. Uklanjanje ovih jedinjenja, koja čine oko 60 % od ukupno sadržanih nesaharoznih materija u soku &scaron;ećerne repe, zasniva se&nbsp; na principu taloženja uz primenu različitih koagulanata (najče&scaron;će jedinjenja koja sadrže pozitivne jone kalcijuma). Međutim, afinitet vezivanja kalcijuma sa nepoželjnim makromolekulima iz soka &scaron;ećerne repe je mali, pa su potrebne velike količine ovog jedinjenja u svakodnevnoj proizvodnji &scaron;ećera.</p><p>Cilj istraživanja obuhvaćenih ovom doktorskom disertacijom usmeren je ka primeni alternativnih koagulanata sa dvo- i trovalentnim katjonima, pre svega soli aluminijuma i bakra koja izlazivaju proces razelektrisavanja makromolekula soka &scaron;ećerne repe.&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; Merenjem elektrokinetičkih potencijala utvrđene su optimalne količine koagulanata potrebne za uspe&scaron;nu koagulaciju makromolekularnih jedinjenja iz soka &scaron;ećerne repe. Ispitivan je i uticaj drugih procesnih veličina kao &scaron;to su pH, koncentracija makromolekula i uticaj brzine me&scaron;anja na efikasnost taloženja makromolekula.&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; Predložen je mehanizam razelektrisavanja makromolekularnih jedinjenja kao i model dvojnogelektričnog sloja koji okružuje&nbsp; koloidne čestice u soku &scaron;ećerne repe.&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; Ispitivana su dva model-rastvora komercijalno raspoloživih pektina u koncentracijama koje odgovaraju koncentracijama u soku &scaron;ećerne repe kao i jedan model-rastvor proteinskog preparata. Ispitivani sistemi su tretirani rastvorima CuSO<sub>4</sub>&nbsp;i Al2(SO<sub>4</sub>)<sub>3</sub> i rastvorima njihovih sme&scaron;a u različitim odnosima.&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; Dokazano je, za sva tri ispitivana preparata, da su manje količine Cu<sup>+2</sup> jona u odnosu na Al<sup>+3</sup><sup>&nbsp;</sup>jone potrebne za sniženje vrednosti Zeta potencijala na nulu. Međutim, zbog mogućih nepoželjnih efekata CuSO<sub>4</sub>&nbsp;u obradi hrane, Al(SO<sub>4</sub>)<sub>3</sub> bi se mogao upotrebiti umesto tradicionalnog koagulanta CaO, kako zbog manje potro&scaron;nje koagulanta, tako i zbog očuvanja životne sredine.&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; Cilj eksperimenata sa sme&scaron;ama je ispitivanje mogućnosti pobolj&scaron;anja koagulacionih karakteristika često kori&scaron;ćene soli&nbsp;Al2(SO<sub>4</sub>)<sub>3</sub>, dodavanjem malih količina Cu<sup>+2</sup> jona. Međutim, čiste soli su pokazale bolja koagulaciona svojstva.&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; Istraživanja sa flokulantima, odnose se na odabiranje najpogodnijeg tipa i optimalne količine flokulanata, uz primenu predloženih koagulanata. Najveća efikasnost či&scaron;ćenja soka &scaron;ećerne repe, uočena je nakon primene anjonskog flokulanta koncentracije 3 mg/dm<sup>3</sup>. Dokazano je da ovaj tip flokulanata dodatno smanjuje vrednost Zeta potencijala prisutnih makromolekula čime se smanjuje potrebna količina ispitivanih koagulanata&nbsp;&nbsp;CuSO<sub>4 </sub>i&nbsp;Al(SO<sub>4</sub>)<sub>3</sub>.</p><p>&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp;</p><p>&nbsp;</p><p><br /><br />&nbsp;</p><p>&nbsp;</p> / <p>During production of full quality consumed white sugar from sugar beet, there is a problem of the presence<br />of macrom olecular compounds in sugar beet juice, which are harmful and we have to be removed.<br />Separation ofthese compounds, which make around 60% oflotal non-sucrose compounds in sugar beetjuice,<br />is done by the principle of sedimentation with different types of coagulants (mostly compounds with calcium<br />ion). However, affinity of calcium binding with undesirable macromolecules fiom sugar beet juice is not<br />significant and in that way it is necessary a lot of quantities of this compound throughout daily production of<br />sugar.<br />The aim of this doctoral thesis is to consider the application of alternative coagulants with divalent and<br />trivalent cations, especially the salt of aluminum and cooper, which cause the process of dischargeable<br />macromolecules in sugar beet juice.<br />Optimal quantities of coagulants needing for the efficient coagulation of macromolecules compounds from<br />sugar beet juice were determined by means of measuring of electrokinetic potentials. It was investigated the<br />influence of other process variables such as pH, concentration of macromolecules and the impact of speed<br />mixing on the efficiency of sedimentation of macromolecules.<br />Mechanism of discharge of macromolecules compounds as well as the model of double electric layer<br />surrounding colloidal particles in sugar beetjuice are suggested for sugar beetjuice clarification.<br />Two model solutions of pectin are investigated together with one model solution of protein. Their<br />concentration correspond to concentration of these macromolecules in sugar beet juice. All investigated<br />systems were treated by using both solutions of CuSO4 as well as Al2(SO4)3 and slutions of their mixtures in<br />different proportion.<br />It was proven for all three investigated samples that fewer quantities of Cu+2 ions compared to the values of<br />Al+3 ions are needed to reach zero Zeta potential. However, due to possible undesirable effects of CuSO4 on<br />food processing, Al2(SO4)3 is proposed instead of traditional coagulant CaO, not only because of lower<br />consumptions of coagulants but owing to protection of the environment.<br />The objective in the experiments with mixtures was to investigate enhancement of coagulated characteristics<br />with commonly used salt Al2(SO4)3 by adding small quantities of Cu+2 ions. It was proven that pure salts<br />showed better-coagulated properties.<br />Further investigation was focused to selection of the most appropriate type and optimal quantity of chosen<br />flocculants. The highest efficiency of clarification of sugar beet juice was noticed by applying anion<br />flocculants of concentration 3 mg/dm3. It was shown that this type of flocculants additionally decreased the<br />value of Zeta potential of present macromolecules which further reduce required quantity of investigated<br />coagulants CuSO4 and Al2(SO4)3.</p>

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