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Adsorção de íons metálicos em meio aquoso, etanólico e cetônico utilizando silsesquioxanos organofuncionalizadosPerujo, Sérgio Daniel [UNESP] 24 June 2013 (has links) (PDF)
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perujo_sd_dr_ilha.pdf: 3975409 bytes, checksum: 20915b5dadee73e9b64313a155116ba3 (MD5) / Neste trabalho, primeiramente foi sintetizado o octa (3-cloropropil) silsesquioxano (OCS), por meio da condensação hidrolítica do 3-Cloropropil trietoxisilano. Na sequência, foram preparados dois adsorventes a partir da organofuncionalização do OCS com os ligantes 2- mercaptopirimidina (2-MCP) e o 2-amino-1,3,4-tiadiazol (ATD), resultando os materiais: octa (2-mercaptopirimidinapropil) silsesquioxano (2-MCP-SSQ) e o octa (2-amino-1,3,4- tiadiazolpropil) silsesquioxano (ATD-SSQ). Em seguida estes materiais foram caracterizados por meio das técnicas de FTIR, NMR 13 C, NMR 29 Si, SEM, análise elementar e análise termogravimétrica. A análise elementar do nitrogênio indicou um teor de funcionalização de 4,4 e 3,6 mmol g-1 para o 2-MCP-SSQ e o ATD-SSQ, respectivamente. Estes nanoadsorventes foram aplicados na adsorção dos íons metálicos CuX2, CoX2 e NiX2 (X= Cl-, Br- e ClO4-) em soluções aquosas, etanólicas e cetônicas, pelo método de “Batch” (batelada). O tempo de equilíbrio de adsorção para os dois adsorventes estudados foi de aproximadamente 40 minutos para os íons metálicos em todos os solventes estudados. Foi observado que as capacidades máximas de adsorção (Nfmáx) nos solventes estudados obedeceram a ordem cetônico > etanólico >> aquoso. Nos meios etanólico e cetônico a adsorção obedece a seguinte ordem: Cu2+ > Co2+ > Ni2+ e em meio aquoso: Ni2+ > Co2+ > Cu2+. As isotermas de adsorção foram ajustadas aos modelos de Langmuir, Freundlich, Temkin e Dubinin-Radushkevich (D-R). Foram aplicados os modelos cinéticos de adsorção de pseudo-primeira-ordem, pseudo-segunda-ordem e Elovich, e os modelos de difusão de Boyd & Reichenberg e de difusão intrapartícula. Os modelos de Langmuir, pseudo-segunda- ordem e de Boyd & Reichenberg foram os mais apropriados para... / In this work, first the octa (3-chloropropyl) silsesquioxane (OCS) was synthesized by hydrolytic condensation of the 3-chloropropyl triethoxysilane. In the following, two adsorventes were prepared from the OCS organofunctionalization with the ligands 2- mercaptopyrimidine (2-MCP) and 2-amino-1,3,4-thiadiazole (ATD), resulting the materials octa (2-mercaptopyrimidinepropyl) silsesquioxane (2-MCP-SSQ) and octa (2-amino-1,3,4- tiadiazolpropyl) silsesquioxane (ATD-SSQ). Then the material was characterized by the techniques of FTIR, 13 C-NMR, 29 Si-NMR, SEM, elemental analysis and thermogravimetric analysis. The nitrogen elemental analysis indicated a degree of functionalization of 4.4 and 3.6 mmol g-1 for the 2-MCP-SSQ and ATD-SSQ, respectively. These nanoadsorventes were applied to the adsorption of metal ions CuX2, CoX2 and NiX2 (X = Cl-, Br- and ClO4-) in aqueous, ethanolic and ketone solutions by the batch method. The time of adsorption equilibrium for the two adsorbents studied was approximately 40 minutes for all solvents and metal ions. It was observed that the maximum adsorption capacity (Nfmáx) in the solvents studied obeyed the order ketone > ethanolic > > aqueous. In ethanol and ketone media the adsorption obeys the following order: Cu2+ > Co2+ > Ni2+ and aqueous: Ni2+ > Co2+ > Cu2+. The adsorption isotherms were fitted to Langmuir, Freundlich, Temkin and Dubinin- Radushkevich (D-R). It were applied the kinetic models of adsorption pseudo-first-order, pseudo-second-order and Elovich and diffusion models of Boyd & Reichenberg and intraparticle diffusion. The Langmuir, pseudo-second-order and Boyd & Reichenberg models were the most appropriate to describe the data of adsorption, kinetics and diffusion, respectively. The thermodynamic parameters ΔG, ΔH and ΔS were... (Complete abstract click electronic access below)
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Reator contínuo com leito de lodo biológico anaeróbio para a remoção de íons metálicos em solução aquosa /Mendonça, Marília Assunção. January 2016 (has links)
Orientador: Roberto Alves Oliveira / Coorientador: Allynson Takehiro Fujita / Banca: Mariana Carina Frigieri / Banca: Luciano dos Santos Rodrigues / Resumo: Reatores contínuos com leito de lodo biológico anaeróbio, in natura e seco em estufa, foram utilizados para a remoção de metais (Cu+2, Mn+2 e Zn+2) em solução aquosa. Com o lodo in natura avaliou-se o efeito conjunto da bioacumulação e biossorção; e com o lodo seco em estufa o efeito exclusivo da biossorção. Foram utilizadas baixas concentrações de Cu+2, Mn+2 e Zn+2 (0,01 a 5,00 mg L-1), tendo em vista que para a ocorrência de bioacumulação devem ser mantidas condições não tóxicas para os micro-organismos. Portanto, os resultados poderão ser aplicados para o pós-tratamento de efluentes com concentrações remanescentes desses metais, que necessitem de polimento para a disposição final, atendendo aos limites legais de qualidade de água do corpo receptor. Os lodos utilizados foram coletados de reatores anaeróbios horizontal (RAH) e de fluxo ascendente com manta de lodo (UASB) utilizados no tratamento de águas residuárias de suinocultura. A temperatura foi controlada a 20°C em todos os ensaios. Foram avaliadas vazões de 5, 10 e 15 mL min-1, valores de pH 4,0 e 6,0 e concentrações de 0,01, 0,5 e 1,0 mg L-1 de Cu2+ e Mn2+, e de 0,05; 2,5 e 5,0 mg L-1 de Zn2+. O pH ótimo para a remoção de Mn2+ e Zn2+ foi 4,0 e para o Cu2+ não foi verificada diferença. A maior eficiência foi encontrada quando utilizou-se os menores valores de concentração e fluxo para os três biossorventes avaliados. Foi verificado que os valores de concentração de metais utilizados demonstraram não serem tóxicos para... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: Continuous reactors with anaerobic biological sludge bed, in nature and dry in an oven, were used for removal of metals (Cu+2, Mn+2 and Zn+2 ) in aqueous solution. With the sludge in natura it was evaluated the combined effect of bioaccumulation and biosorption; and the dry sludge in greenhouse sole effect of biosorption. It was used lower concentrations of Cu+2, Mn+2 and Zn+2 (0.01 to 5.00 mg L -1 ), considering that for bioaccumulation occurring should be kept non-toxic conditions for the micro-organisms. Therefore, the results can be applied to the posttreatment of effluents with remaining concentrations of these metals, which require polishing to final disposal, meeting the legal limits of quality of the receiving water body. The used sludges were collected from horizontal anaerobic reactors (RAH) and ascendant upflow sludge blanket (UASB) used in the treatment of swine wastewater. The temperature was controlled at 20°C in all tests. It was analyzed outputs of 5, 10 and 15 ml min-1, pH values 4.0 and 6.0 and concentrations of 0.01, 0.5 and 1.0 mg L- 1 Cu+2 and Mn+2, and 0.05; 2.5 and 5.0 mg L -1 Zn+2 . The optimum pH for the removal of Mn+2 and Zn+2 was 4.0 and the Cu+2 it was not verified difference. The highest efficiency was found when it was used the lowest values of concentration and flux for all three reviews biosorbents. It has been found that the metals concentration values used proved not to be toxic to cells of microorganisms present in the sludge in nature,... (Complete abstract click electronic access below) / Mestre
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Adsorção de íons metálicos em meio aquoso, etanólico e cetônico utilizando silsesquioxanos organofuncionalizados /Perujo, Sérgio Daniel. January 2013 (has links)
Orientador: Newton Luiz Dias Filho / Banca: Devaney Ribeiro do Carmo / Banca: Ezequiel Costa Siqueira / Banca: Cesar Ricardo Teixeira Tarley / Banca: Luciana Camargo de Oliveira / Resumo: Neste trabalho, primeiramente foi sintetizado o octa (3-cloropropil) silsesquioxano (OCS), por meio da condensação hidrolítica do 3-Cloropropil trietoxisilano. Na sequência, foram preparados dois adsorventes a partir da organofuncionalização do OCS com os ligantes 2- mercaptopirimidina (2-MCP) e o 2-amino-1,3,4-tiadiazol (ATD), resultando os materiais: octa (2-mercaptopirimidinapropil) silsesquioxano (2-MCP-SSQ) e o octa (2-amino-1,3,4- tiadiazolpropil) silsesquioxano (ATD-SSQ). Em seguida estes materiais foram caracterizados por meio das técnicas de FTIR, NMR 13 C, NMR 29 Si, SEM, análise elementar e análise termogravimétrica. A análise elementar do nitrogênio indicou um teor de funcionalização de 4,4 e 3,6 mmol g-1 para o 2-MCP-SSQ e o ATD-SSQ, respectivamente. Estes nanoadsorventes foram aplicados na adsorção dos íons metálicos CuX2, CoX2 e NiX2 (X= Cl-, Br- e ClO4-) em soluções aquosas, etanólicas e cetônicas, pelo método de "Batch" (batelada). O tempo de equilíbrio de adsorção para os dois adsorventes estudados foi de aproximadamente 40 minutos para os íons metálicos em todos os solventes estudados. Foi observado que as capacidades máximas de adsorção (Nfmáx) nos solventes estudados obedeceram a ordem cetônico > etanólico >> aquoso. Nos meios etanólico e cetônico a adsorção obedece a seguinte ordem: Cu2+ > Co2+ > Ni2+ e em meio aquoso: Ni2+ > Co2+ > Cu2+. As isotermas de adsorção foram ajustadas aos modelos de Langmuir, Freundlich, Temkin e Dubinin-Radushkevich (D-R). Foram aplicados os modelos cinéticos de adsorção de pseudo-primeira-ordem, pseudo-segunda-ordem e Elovich, e os modelos de difusão de Boyd & Reichenberg e de difusão intrapartícula. Os modelos de Langmuir, pseudo-segunda- ordem e de Boyd & Reichenberg foram os mais apropriados para... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: In this work, first the octa (3-chloropropyl) silsesquioxane (OCS) was synthesized by hydrolytic condensation of the 3-chloropropyl triethoxysilane. In the following, two adsorventes were prepared from the OCS organofunctionalization with the ligands 2- mercaptopyrimidine (2-MCP) and 2-amino-1,3,4-thiadiazole (ATD), resulting the materials octa (2-mercaptopyrimidinepropyl) silsesquioxane (2-MCP-SSQ) and octa (2-amino-1,3,4- tiadiazolpropyl) silsesquioxane (ATD-SSQ). Then the material was characterized by the techniques of FTIR, 13 C-NMR, 29 Si-NMR, SEM, elemental analysis and thermogravimetric analysis. The nitrogen elemental analysis indicated a degree of functionalization of 4.4 and 3.6 mmol g-1 for the 2-MCP-SSQ and ATD-SSQ, respectively. These nanoadsorventes were applied to the adsorption of metal ions CuX2, CoX2 and NiX2 (X = Cl-, Br- and ClO4-) in aqueous, ethanolic and ketone solutions by the batch method. The time of adsorption equilibrium for the two adsorbents studied was approximately 40 minutes for all solvents and metal ions. It was observed that the maximum adsorption capacity (Nfmáx) in the solvents studied obeyed the order ketone > ethanolic > > aqueous. In ethanol and ketone media the adsorption obeys the following order: Cu2+ > Co2+ > Ni2+ and aqueous: Ni2+ > Co2+ > Cu2+. The adsorption isotherms were fitted to Langmuir, Freundlich, Temkin and Dubinin- Radushkevich (D-R). It were applied the kinetic models of adsorption pseudo-first-order, pseudo-second-order and Elovich and diffusion models of Boyd & Reichenberg and intraparticle diffusion. The Langmuir, pseudo-second-order and Boyd & Reichenberg models were the most appropriate to describe the data of adsorption, kinetics and diffusion, respectively. The thermodynamic parameters ΔG, ΔH and ΔS were... (Complete abstract click electronic access below) / Doutor
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The Exchange of Bismuth Tetra-Iodide and Bismuth Ions in an Ion-Precipitate SystemPitts, James William 01 1900 (has links)
This paper is a study of the exchange of bismuth tetra-iodide and bismuth ions in an ion-precipitate system.
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Photodecomposition of the ethylenediaminetetraacetatoferrate (III) ionGodsey, Charles Edward. January 1959 (has links)
Call number: LD2668 .T4 1959 G63
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Metal ion mediated hydrolysis of 4-nitrophenylphosphate in microemulsion media: catalytic versus stoichiometric effectsEguzozie, Kennedy Uchenna 05 1900 (has links)
The hydrolysis of 4-Nitrophenylphosphate (NPP) as model substrate in the presence of
several cobalt (III) amine [N4Co(OH)(H2O)]2+ and copper bipyridyl [Cu(bpy)(H2O)2]2+
complexes in oil in water microemulsion media was investigated. The reaction was
monitored by measuring the absorbance of the nitrophenolate ion produced in the
reaction aliquots with time under the experimental conditions. The order of effectiveness
of the microemulsion systems towards the hydrolysis of NPP in the presence of
these metal ions were found to be cationic > anionic > aqueous at neutral pH. The
results of the present investigation exhibits stoichiometric turnovers for the 1:1, 2:1 and
3:1 cobalt to NPP ratio and catalytic turnovers for the [Cu(bpy)2+ to NPP ratio of 1:20.
Catalysis in the microemulsion mediated reaction solutions was evident even in low
concentrations of the metal ions in 1:2000 metal to NPP ratio. An explanation for the
enhanced catalytic activity of the [Cu(bpy)(OH)(H2O)]2+ complex for the hydrolysis of
NPP is afforded and the application of the above model systems for possible
environmental decontamination of toxic organophosphates is anticipated. / Chemistry / M.Sc. (Chemistry)
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Synthesis and photophysical properties of oligo (arylene-ethynylene)s,osmium(II) diimine and platinum(II) calix[4] arene complexes and theirapplications as sensory materialsChan, Kwok-wai, Queenie., 陳幗慧. January 2008 (has links)
published_or_final_version / Chemistry / Doctoral / Doctor of Philosophy
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The infrared spectrum of the helium molecular ion helium-3 positive helium-4.Yu, Nan. January 1988 (has links)
This dissertation is concerned with the first experimental observation of the vibration-rotation spectrum of the helium molecular ion, ³He⁴He⁺. The Doppler-tuned fast-beam laser-resonance technique has been used. The ions produced in an electron-impact ion source form an ion beam of a few KeV and then intersect nearly colinearly with a CO IR laser beam of fixed frequency. The velocity of the ions is scanned to tune the ions into resonance with the laser frequency. Subsequent resonance detection is realized by using charge exchange processes of the ion with a target gas. Twelve spectral lines have been measured which correspond to nine different vibration-rotation transitions of the R branch in the fundamental band of the ground state of ³He⁴He⁺. The combination of the kinematic compression of the fast-beam method and the special frequency stabilization of the CO laser render an experimental accuracy of 0.0006 cm⁻¹ or 0.4 ppm. The accuracy exceeds that of the available theory by three orders of magnitude. The narrow spectral linewidth also allows partial resolution of the magnetic hyperfine structure due to helium-3. A hyperfine structure calculation has been carried out using a numerical multi-configuration self-consistent-field method. The agreement between the calculation and the observation is very satisfying.
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OBSERVATION OF THE INFRARED SPECTRA OF THE DEUTERATED TRIATOMIC HYDROGEN MOLECULAR TONS: H₂D⁺, HD₂⁺, and D₃⁺SHY, JOW-TSONG. January 1982 (has links)
The infrared vibrational-rotational spectra of the deuterated triatomic hydrogen molecular ions, H₂D⁺, HD₂⁺, and D₃⁺ have been observed with the Doppler-tuned ion-beam laser spectroscopic method with collision detection. Triatomic hydrogen molecular ions are produced in a coaxial electron-impact ion source. Next, the ions are accelerated and formed into a beam of several keV energy, which is then intercepted at a small angle by a frequency-stabilized CO laser beam. The energy of the ion beam is adjusted to Doppler-shift an ion transition into resonance with a nearby laser line. On resonance, the laser light stimulates the transition to take place. If the resonating states differ in population, the laser-induced transition produces a net population transfer. The occurrence of population transfer is detected by monitoring the transmission of the ion beam through a gas target after laser interaction. The transmission through the target is dependent upon the ion beam population distribution and, therefore, the laser-induced transition can be detected by detecting the change of the transmission of the ion beam. A mass analyzer before the target gas facilitates the mass identification of the observed transitions. We have measured 45 D₃⁺ transition frequencies, 9 H₂D⁺ transition frequencies, and 31 HD₂⁺ transition frequencies, all between 1650 and 2000 cm⁻¹, to better than ±0.0005 cm⁻¹ or ±0.3 ppm. The identifications of the quantum numbers are still in progress. This study should greatly help the search of H₃⁺ and H₂D⁺ ions in interstellar medium.
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Analysis and computer-based modelling of citric acid production by Aspergillus nigerWayman, Francis Michael January 2001 (has links)
No description available.
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