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Pre-fermentation maceration of pinot noir wineGoldsworthy, S. A. January 1993 (has links)
Two pre-fermentation treatments were investigated in Pinot noir (Vitis vinifera L.) wines. The effects of cold maceration and carbonic maceration on the wines' composition, colour parameters and sensory properties were examined. Cold maceration is a winemaking technique used to increase non-alcoholic extraction in Pinot noir winemaking prior to fermentation. It involves holding crushed grapes with approximately 100-150 mg l⁻¹ SO₂ at low temperatures and is thought to increase the colour, aroma and flavour of the resulting wines. Carbonic maceration uses whole bunches that have undergone anaerobic metabolism to produce characteristically fruity and spicy wines. Pre-fermentation cold maceration produces wines that are higher in titratable acidity and monomeric anthocyanin content, but lower in colour density, hue and polymeric pigments. Reducing the maceration temperature below 10°C has little effect. Carbonic maceration produces wines that are lower in titratable acidity, monomeric anthocyanin content, and colour density but are higher in colour hue and amount of polymeric pigments. Quantitative descriptive analysis was used to define the effects of these pre-fermentation maceration treatments on the sensory characteristics of the resulting wine. Trained panel members found that there were no discernable sensory differences in the compositional parameters despite measurable chemical differences. Investigation into the aroma and flavour characteristics of the wines found that carbonic maceration produces wines that were lower in berry aroma and higher in acetate or ester-type aromas than the control wines. These wines were considered to have specific raspberry, floral, sugar, cherry and chemical aromas. This chemical note was also observed in the flavour of the carbonic maceration wines. The temperature of the cold maceration process has no major effect on the aroma and flavour of the resulting wines. However, the 10°C maceration was higher in woody/tobacco aroma than the 4°C maceration, and the 10°C treatment was also higher in bitter flavour than all the other treatments. Cold maceration wines were found to have specific mixed berry, dried fruit and sweet-oxidised aroma characters, together with a blackberry flavour note.
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Targeting Mycobacterium tuberculosis Proteins: Structure and Function Studies of Five Essential ProteinsSuarez Covarrubias, Adrian January 2008 (has links)
This thesis describes the target selection, cloning, expression, purification, crystallization, structure and biochemical characterization of five essential Mycobacterium tuberculosis (Mtb) proteins. The search for drugs against the causal agent of tuberculosis is urgently needed and the targeting of essential genes is necessary to fulfill this goal. The crystal structures of carbonic anhydrases (CA) Rv1284 and Rv3588c have been determined to 2.0 and 1.7 Å resolution, respectively. Rv3588c, in contrast to Rv1284, is an active β-CA that shows two different active site conformations and pH-dependent oligomerization states. Rv1295 is an active threonine synthase with an unusually high pH optimum; the structure has been solved to 2.5 Å resolution, based on which a modification to the reaction mechanism published previously is proposed. Mtb has a thick and impermeable cell envelope that constitutes an efficient barrier against drugs. One of the essential components of the envelope is mycolic acid (MA). The inhibition of enzymes participating in its synthesis would be lethal for Mtb. Rv0636, a formerly unknown-function protein has β-hydroxyacyl-ACP dehydrase activity which is essential for MA synthesis. Co-expression with partners notably improves its solubility. Around 55% of Mtb proteins have unknown function. Rv3778c is one of them and its three-dimensional structure has been determined to 1.8 Å resolution. Studies aimed at the elucidation of its biochemical function are shown. A pathway not yet reported in Mtb is also suggested.
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The Role of Carbonic Anhydrase in the Modulation of Central Respiratory-related pH/CO2 Chemoreceptor-stimulated Breathing in the Leopard Frog (Rana pipiens) Following Chronic Hypoxia and Chronic HypercapniaSrivaratharajah, Kajapiratha 26 February 2009 (has links)
The aim of this thesis was to elucidate the role of carbonic anhydrase (CA) in the modulation of central pH/CO2-sensitive fictive breathing (measured using in vitro brainstem-spinal cord preparations) in leopard frogs (Rana pipiens) following exposure to chronic hypercapnia (CHC) and chronic hypoxia (CH). CHC caused an augmentation in fictive breathing compared to the controls (normoxic normocapnic). Addition of acetazolamide (ACTZ), a cell-permeant CA inhibitor, to the superfusate reduced fictive breathing in the controls and abolished the CHC-induced augmentation of fictive breathing. ACTZ had no effect on preparations taken from frogs exposed to CH. Addition of bovine CA to the superfusate did not alter fictive breathing in any group, suggesting that the effects of ACTZ were due to inhibition of intracellular CA. Taken together, these results indicate that CA is involved in central pH/CO2 chemoreception and the CHC-induced increase in fictive breathing in the leopard frog.
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The Role of Carbonic Anhydrase in the Modulation of Central Respiratory-related pH/CO2 Chemoreceptor-stimulated Breathing in the Leopard Frog (Rana pipiens) Following Chronic Hypoxia and Chronic HypercapniaSrivaratharajah, Kajapiratha 26 February 2009 (has links)
The aim of this thesis was to elucidate the role of carbonic anhydrase (CA) in the modulation of central pH/CO2-sensitive fictive breathing (measured using in vitro brainstem-spinal cord preparations) in leopard frogs (Rana pipiens) following exposure to chronic hypercapnia (CHC) and chronic hypoxia (CH). CHC caused an augmentation in fictive breathing compared to the controls (normoxic normocapnic). Addition of acetazolamide (ACTZ), a cell-permeant CA inhibitor, to the superfusate reduced fictive breathing in the controls and abolished the CHC-induced augmentation of fictive breathing. ACTZ had no effect on preparations taken from frogs exposed to CH. Addition of bovine CA to the superfusate did not alter fictive breathing in any group, suggesting that the effects of ACTZ were due to inhibition of intracellular CA. Taken together, these results indicate that CA is involved in central pH/CO2 chemoreception and the CHC-induced increase in fictive breathing in the leopard frog.
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Synthesis of carbonic anhydrase inhibitors and analysis of their structure - activity relationship / Karboanhidrazių slopiklių sintezė ir jų struktūros - aktyvumo tyrimasČapkauskaitė, Edita 11 December 2012 (has links)
The aim of this work was formulated - the synthesis of potent human carbonic anhydrase inhibitors, and their structure - activity study.
The synthesized 136 new compounds were subjected to the studies of their inhibitory activity towards CA I, II, VII, XII and XIII (VU IBT). An efficient method for N-and S-alkylation of heterocyclic compounds (benzimidazole), S-alkylation of heterocyclic and aromatic compounds (imidazole, benzothiazole, benzimidazothiadiazole, pyrimidine, benzenethiol) with 3 - and 4 - (bromoacetyl)benzenesulfonamides and 4 - and 5 - (bromoacetyl)-2-chlorobenzenesulfonamides has ben deveoped. 2-[(6-oksopyrimidine-2-yl)thio]acetylbenzenesulfonamides in dimethylsulfoxide solution were found to exists in two forms - open chain and cyclic.
4-(Hetarylmethylcarbonyl)benzenesulfonamides exibited more inhibitory potency to CA than the 3-(hetarylmethylcarbonyl)benzenesulfonamides. Among all compound studied S-alkylated benzenethiol derivatives exibit the best CA inhibitory properties, while 1,3-thiazole derivatives – the lowest. Sulfonamide group position on the benzene ring is more important for CA binding than the acidic properties of sulfonamide group. The inhibitors having the selectivity of any one CA were selected from synthesized compounds. Most of the compounds possess selectivity to CA I and CA XIII, while selectivity to CA XII almost is not observed. The benzenesulfonamide ring position in CA II active site is unique to each class of compounds as showed in... [to full text] / Šio darbo tikslas – potencialių žmogaus karboanhidrazių (CA) slopiklių sintezė ir jų struktūros – aktyvumo tyrimas.
CA slopinimo tyrimams susintetinti 136 įvairiais heterociklais pakeisti benzensulfonamidai ir išmatuotas jų CA I, II, VI, XII ir XIII slopinimo aktyvumas (VU BTI mokslininkai). Paruoštos efektyvios benzimidazolų N- ir S-alkilinimo, imidazolų, benztiazolo, benzimidazotiadiazolo, pirimidinų, benzenalkiltiolių S-alkilinimo 3- ir 4-(bromacetil)benzensulfonamidais bei 4- ir 5-(bromacetil)-2-chlorbenzensulfonamidais metodikos. Nustatyta, kad [(6-oksopirimidin-2-il)tio]acetilbenzensulfonamidai tirpaluose egzistuoja atviroje ir ciklinėje formose. Ištyrus benzensulfonamidinio ir heterociklinio/aromatinio fragmentų struktūros įtaka CA slopinančioms savybėms nustatyta, kad benzensulfonamidinės dalies įtaka CA slopinančiam aktyvumui yra didesnė nei heterociklinės/aromatinės. Sulfonamidinės grupės padėties benzeno žiede įtaka jungimuisi prie CA yra reikšmingesnė nei sulfonamidinės grupės rūgštingumo įtaka. Tiriant atrankumą vienai CA nustatyta, kad iš visų junginių daugiausiai atrankių yra CA I ir XIII, o CA XII atrankių junginių beveik nėra. Daugiausiai kuriai nors CA atrankių junginių yra tarp 4-(hetarilmetilkarbonil)benzensulfonamidų, bei tarp 1,3-tiazolo ir benzenalkiltiolio darinių.
Remiantis rentgenostruktūrine CA II, XII ir XIII kompleksų (VU BTI) su kai kuriais slopikliais analize, paaiškintas sumažėjęs junginių giminingumas CA XII, lyginant su CA II, sumažėjęs... [toliau žr. visą tekstą]
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Karboanhidrazių slopiklių sintezė ir jų struktūros - aktyvumo tyrimas / Synthesis of carbonic anhydrase inhibitors and analysis of their structure - activity relationshipČapkauskaitė, Edita 11 December 2012 (has links)
Šio darbo tikslas – potencialių žmogaus karboanhidrazių (CA) slopiklių sintezė ir jų struktūros – aktyvumo tyrimas.
CA slopinimo tyrimams susintetinti 136 įvairiais heterociklais pakeisti benzensulfonamidai ir išmatuotas jų CA I, II, VI, XII ir XIII slopinimo aktyvumas (VU BTI mokslininkai). Paruoštos efektyvios benzimidazolų N- ir S-alkilinimo, imidazolų, benztiazolo, benzimidazotiadiazolo, pirimidinų, benzenalkiltiolių S-alkilinimo 3- ir 4-(bromacetil)benzensulfonamidais bei 4- ir 5-(bromacetil)-2-chlorbenzensulfonamidais metodikos. Nustatyta, kad [(6-oksopirimidin-2-il)tio]acetilbenzensulfonamidai tirpaluose egzistuoja atviroje ir ciklinėje formose. Ištyrus benzensulfonamidinio ir heterociklinio/aromatinio fragmentų struktūros įtaka CA slopinančioms savybėms nustatyta, kad benzensulfonamidinės dalies įtaka CA slopinančiam aktyvumui yra didesnė nei heterociklinės/aromatinės. Sulfonamidinės grupės padėties benzeno žiede įtaka jungimuisi prie CA yra reikšmingesnė nei sulfonamidinės grupės rūgštingumo įtaka. Tiriant atrankumą vienai CA nustatyta, kad iš visų junginių daugiausiai atrankių yra CA I ir XIII, o CA XII atrankių junginių beveik nėra. Daugiausiai kuriai nors CA atrankių junginių yra tarp 4-(hetarilmetilkarbonil)benzensulfonamidų, bei tarp 1,3-tiazolo ir benzenalkiltiolio darinių.
Remiantis rentgenostruktūrine CA II, XII ir XIII kompleksų (VU BTI) su kai kuriais slopikliais analize, paaiškintas sumažėjęs junginių giminingumas CA XII, lyginant su CA II, sumažėjęs... [toliau žr. visą tekstą] / The aim of this work was formulated - the synthesis of potent human carbonic anhydrase inhibitors, and their structure - activity study.
The synthesized 136 new compounds were subjected to the studies of their inhibitory activity towards CA I, II, VII, XII and XIII (VU IBT). An efficient method for N-and S-alkylation of heterocyclic compounds (benzimidazole), S-alkylation of heterocyclic and aromatic compounds (imidazole, benzothiazole, benzimidazothiadiazole, pyrimidine, benzenethiol) with 3 - and 4 - (bromoacetyl)benzenesulfonamides and 4 - and 5 - (bromoacetyl)-2-chlorobenzenesulfonamides has ben deveoped. 2-[(6-oksopyrimidine-2-yl)thio]acetylbenzenesulfonamides in dimethylsulfoxide solution were found to exists in two forms - open chain and cyclic.
4-(Hetarylmethylcarbonyl)benzenesulfonamides exibited more inhibitory potency to CA than the 3-(hetarylmethylcarbonyl)benzenesulfonamides. Among all compound studied S-alkylated benzenethiol derivatives exibit the best CA inhibitory properties, while 1,3-thiazole derivatives – the lowest. Sulfonamide group position on the benzene ring is more important for CA binding than the acidic properties of sulfonamide group. The inhibitors having the selectivity of any one CA were selected from synthesized compounds. Most of the compounds possess selectivity to CA I and CA XIII, while selectivity to CA XII almost is not observed. The benzenesulfonamide ring position in CA II active site is unique to each class of compounds as showed in... [to full text]
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Equilibrium studies of ternary aluminium(III) hydroxo complexes with ligands related to conditions in natural watersÖhman, Lars-Olof January 1983 (has links)
The thesis is a summary and discussion of eight papers. During the last decades, precipitation has become increasingly acidic due to the extensive use of fossil fuels. In areas of poorly buffered bedrocks, e.g. Scandinavia, northeastern United States, this phenomenon has resulted in elevated amounts of Al(III) being leached into streams and lakes. Recent findings reveal that these elevated Al-concentrations could cause fish death and decreasing forest production. In the present thesis, the importance of taking naturally occurring substances into consideration when discussing Al(III) in natural waters, is emphasized. On the basis of a chemical characterization of relevant ligand classes in a natural water, the complex formation between Al^+, hydroxide ions and the inorganic ligand carbonic acid, the low-molecular weight organic ligand citric acid and the high-molecular weight model substances gallic acid, 1,2-dihydroxynaphtha-lene-4-sulfonate, 1,2-naphthoquinone-4-sulfonate, pyrocatechol and salicylic acid were investigated. The investigations were performed as series of Potentiometrie titrations and data were processed by means of the least-squares computer program LETAGROPVRID using a technique called pqr-analysis, permitting an unbiased search for complex model (and corresponding equilibrium constants) to be made. In most systems studied, the complexation at high ligand excesses can be described by a series of mononuclear complexes AIL-AIL^. Tentatively, the whole series consists of octahedrally coordinated (water and ligand oxygens) AI(III). At lower ligand excesses, the significance and in some cases even predominance of ternary mono- and polynuclear hydroxo complexes is demonstrated. In two of the systems, binary aluminium hydroxo species are evaluated. The potential importance of the substances with respect to Al-com-plexation in natural waters are indicated in a number of model calculations. The solubility of the clay mineral kaolinite is calculated as a function of -lg[H+] and ligand concentration. It is shown that citric acid, gallic acid, 1,2-dihydroxynaphthalene-4-sulfonate, pyrocatechol and salicylic acid contribute quite significant to the total solubilities, even at very low concentrations. As a complement and background to the equilibrium studies, the corrosion rate for one of the naturally occurring Al-bearing minerals, corundum, is reported. In this investigation, performed with a leach-ant solution of ground-water composition, an experimental technique was employed which made it possible to divide the corrosion into chemical and mechanical losses. / <p>Diss. (sammanfattning) Umeå : Umeå universitet, 1983</p> / digitalisering@umu
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Développement d'un vecteur bactérien pour l'immunothérapie anti-tumorale active et spécifique et caractérisation de la réponse immune induite / Development of a bacterial vector for active specific antitumor immunotherapy and characterization of the related immune response.Chauchet, Xavier 01 October 2014 (has links)
Malgré les programmes de dépistage mis en place et le vaste arsenal thérapeutique disponible, 8,2 millions de décès dans le monde ont été attribués au cancer pour l'année 2012 (données Globocan 2012, OMS). L'immunothérapie antitumorale est en plein essor et consiste notamment à exploiter le système immunitaire de l'hôte pour obtenir une réponse contre la tumeur. L'utilisation de vecteurs bactériens, capables de délivrer un message antigénique et de stimuler de manière concomittante l'immunité innée, fait partie des approches de vaccination antitumorale prometteuses. Parmi ces vecteurs, une bactérie Pseudomonas aeruginosa mise au point par notre laboratoire présente l'intérêt de pouvoir injecter in vivo des antigènes de tumeur, via son système de sécrétion de type III (SST3), directement dans le compartiment intracellulaire des cellules présentatrices d'antigènes. La voie de présentation du CMH I est ainsi favorisée et permet la génération d'une réponse des lymphocytes T cytotoxiques vis-à-vis de la tumeur exprimant l'antigène. Cependant, la poursuite des études précliniques et cliniques paraît délicate, en raison du risque infectieux lié à une bactérie pathogène, quand bien même atténuée. Lors de ce travail, nous avons donc développé une nouvelle souche de P. aeruginosa Killed But Metabolically Active (KBMA), incapable de se répliquer, mais toujours apte à jouer son rôle de vecteur. Une analyse de la réponse immune antitumorale, suite à l'immunisation par différents vecteurs, a permis de mettre en évidence une forte infiltration de la tumeur par des lymphocytes T CD8+ spécifiques de l'antigène, mais également une protection à long terme liée à la présence d'un pool majoritaire de lymphocytes T CD8+ spécifiques effecteurs mémoires. Enfin nous avons cherché à appliquer cette technologie à l'antigène de tumeur anhydrase carbonique 9 (AC9), exprimé par de nombreuses tumeurs solides chez l'homme. / Despite cancer screening programs and the available therapeutic armamentarium, 8.2 million deaths worldwide were due to cancer in 2012 (data Globocan 2012, WHO). The antitumor immunotherapy is booming and aims at using the immune system of the host as a response against the tumor. The use of bacterial vectors, able to deliver an antigenic message and concomitantly stimulate innate immunity, is one of the most promising approaches to antitumor vaccination. Among these vectors, the bacterium Pseudomonas aeruginosa developed by our laboratory has the advantage of being able to inject in vivo tumor antigens via its type III secretion system (T3SS) directly in the intracellular compartment of antigen-presenting cells. The MHC I presentation pathway is thus favored and allows the generation of a cytotoxic T lymphocytes response against antigen-expressing tumors. However, further preclinical and clinical studies remain difficult, because of the risk of infection related to a bacterial pathogen, even if attenuated. In this work, we have developed a new strain of P. aeruginosa Killed But Metabolically Active (KBMA) unable to replicate, but still able to play its role as a vector. An analysis of the antitumor immune response following immunization with different vectors, allowed to demonstrate a strong tumor infiltration by antigen-specific CD8+ T lymphocytes, but also a long-term protection related to the presence of a major pool of antigen-specific effector memory CD8+ T cells. Finally we are seeking to apply this technology to the tumor antigen carbonic anhydrase 9 (CA9), expressed by many solid tumors in humans.
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Estudo microclimático do ambiente de cavernas, Parque Estadual Intervales, SP / Microclimate study of caves enviroment, Parque Estadual Intervales, SPBárbara Nazaré Rocha 31 August 2010 (has links)
A proteção ambiental dos recursos geológicos é uma questão com crescente interesse. A exploração de cavernas é uma das formas de turismo associada a recursos geológicos mais difundida. Por isso, deve-se conhecer suas características ambientais, tais como os climáticas, para definir estratégias de gestão e conservação ambiental associadas a seu uso turístico. Assim, o objetivo geral da pesquisa é detectar as principais alterações microclimáticas ocorridas no ambiente cavernícola em decorrência das visitas turísticas no interior das grutas do PEI, SP. Como objetivos específicos, definiu-se: caracterizar o microclima do ambiente de caverna em condições naturais e elencar características físicas da cavidade que influenciem em seu microclima. A metodologia consistiu na coleta de dados de temperatura e umidade relativa do ar de nove cavidades com registradores autônomos. Também foram registrados os valores de CO2. A variação dos atributos do clima foi analisada em situação natural e na presença de visitantes. Os resultados mostram que o microclima das cavernas tende à estabilidade dos valores de temperatura do ar e apresentam umidade relativa do ar e concentração de gás carbônico elevada. Cavernas com rios caudalosos e claraboias não apresentam impacto em sua atmosfera decorrente do turismo, pois as trocas gasosas com o meio externo são facilitadas. Nas grutas secas e afóticas, com entradas e corredores estreitos, o microclima tende à estabilidade, estando mais sujeito a impactos, especialmente elevações na temperatura do ar. O uso de carbureteira também gera acréscimos significativos nas concentrações de gás carbônico. / The ambient protection of the geologic resources is a question with increasing interest. The caves exploration is one of the geological tourism forms more spread out. Therefore, the characteristics of its ambient must be known, such as the climatic ones, to define strategies of management and ambient conservation associates with its tourist use. Thus, the general objective of this research is to detect the main microclimatic alterations in the cave environment in result of the tourist visits in the interior of grottos of PEI, SP. As specific objective, it was purposed to characterize the cave microclimate in natural conditions and to detect the physics characteristics of the caves that influence in its microclimate. The methodology consisted in collect data of temperature and relative humidity of the air of nine caves with automatic sensors. Also the values of carbonic gas had been registered. The variation of the climatic attributes was analyzed in natural situation and in presence of visitors. The results show that the caves microclimate tends to have stability values of air temperature and present high values of air relative humidity and carbonic gas concentration. Caves with rivers of great volume and skylights do not present impact in its atmosphere, even in the presence or tourists, because the gaseous exchanges with the external way are facilitated. In dry and dark grottos, with narrow entrances and corridors, the microclimate tends to stability, being subject to impacts, especially rises in the air temperature.
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Conception des catalyseurs hétérogènes bio-inspirés à base de métaux divalents greffés dans des silices mésoporeuses pour l'activation de CO2 / Design of heterogeneous bio-inspired catalysts using divalent metals anchored into mesoporous silica for CO2 activationDoghri, Hanène Kaouther 29 June 2017 (has links)
Des complexes bio-inspirés de zinc(II) ont été ancrés à la surface des nanopores d’une silice mésoporeuse de type MCM-41 adopté la technique du pochoir moléculaire à motifs périodiques pour assurer l’isolation des sites en utilisant des ions TMA+ comme espaceur pour contrôler le greffage des fonctions triméthylsilyle. L’objectif étant de mimer le doigt de zinc de l’anhydrase carbonique, une enzyme qui catalyse la réaction réversible d’hydratation du dioxyde de carbone en bicarbonate. Des complexes aminés de métaux de transition ont été aussi ancrés par analogie au site métallique de l’anhydrase carbonique avec un contrôle du voisinage moléculaire comparable à celui des matériaux contenant les complexes à base de zinc. L’interaction du CO2 adsorbé avec les sites actifs de ces matériaux a été aussi étudiée. Les matériaux intermédiaires sont caractérisés à chaque étape par un panel de techniques, dont DRX, analyses élémentaires, adsorption-désorption d’N2, FT-IR, 29Si RMN, XPS et RPE qui confirment l’intégrité de la structure poreuse et la formation des complexes. / Bio-inspired diethylenetriamine zinc(II) complexes were anchored into the nanopores of hexagonal mesoporous MCM41-like silicas. A step-by-step approach called “Molecular Stencil Patterning” was adopted to perform an in situ synthesis in order to mimic the zinc finger of the carbonic anhydrase. In the presence of a surface-masking pattern of TMA+ ions, some silanol groups were capped using grafted trimethylsilyl functions. Transition metal complexes have also been anchored in analogy to the metallic site of carbonic anhydrase with a molecular vicinity control comparable to that of materials containing zinc complexes. The interaction of adsorbed CO2 with the active sites of these materials has also been studied. The materials were characterized with a panel of techniques including XRD, elemental analysis, N2-adsorption-desorption, FT-IR, 29Si NMR, XPS and EPR that confirm the integrity of the porous structure and the complexes formation.
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