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1
Burton, S. J. "Biomimetic anthraquinone dyes." Thesis, University of Cambridge, 1986. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.383771.
Testo completo
2
Samp, James Christian. "A comprehensive mechanism for anthraquinone mass transfer in alkaline pulping." Diss., Atlanta, Ga. : Georgia Institute of Technology, 2008. http://hdl.handle.net/1853/24767.
Testo completoAbstract (sommario):
Thesis (Ph.D.)--Chemical Engineering, Georgia Institute of Technology, 2008.<br>Committee Chair: Dr. Jeff Empie; Committee Member: Dr. Bill Koros; Committee Member: Dr. Jim Frederick; Committee Member: Dr. Tom McDonough; Committee Member: Dr. Xin-Sheng Chai
3
Wang, Biao. "A catalyzed chemimechanical-anthraquinone pulping." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1997. http://www.collectionscanada.ca/obj/s4/f2/dsk1/tape11/PQDD_0024/NQ50278.pdf.
Testo completo
4
Wang, Biao 1963. "A catalyzed chemimechanical-anthraquinone pulping /." Thesis, McGill University, 1997. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=35431.
Testo completoAbstract (sommario):
A catalyzed chemimechanical-anthraquinone pulping of black spruce wood was investigated in this study. The effect of liquor pH on anthraquinone performance, AQ and mass transfer limitations on chemimechanical pulp properties and the effects of AQ, liquor pH and sulphite concentration on pulping kinetic were studied.<br>It was observed that AQ was not an effective redox catalyst when added to the sulphite liquor at pH 4, but it was very effective at pH 7 and higher. When chemical treatment of chemimechanical pulping was done with the presence of AQ, the sulphur content of pulp was reduced due to preferential reaction of AQ with wood components. AQ, as a pulping agent, is much effective in increasing the delignification rate and at the same time protecting the degradation of carbohydrates.<br>Pulps produced from wood wafers with cooking liquor at pH 7 containing 0.1% of AQ on oven dry wood, exhibited the following improved properties when compared with those prepared without addition of AQ: increased pulping rate, higher pulp yield and carbohydrates yield at the same level of residual lignin in pulp, and in addition, the strength properties such as breaking length and burst strength improved by 15% even with a minimum AQ charge (0.05% and 0.01%).<br>With regular wood chips, the penetration of sulphite seems to be superior to that of AQ. It was observed that AQ was not uniformly distributed in the impregnated wood chips even when the compression ratio was increased from 3.5:1 to 5:1. The penetration of AQ into wood chips remains to be a major factor affecting the pulping rate and pulp properties (strength and brightness) in chemimechanical-AQ pulping.<br>The rate of delignification in the initial phase of both sulphite and sulphite-AQ cooking at pH 7 shows the second order reaction in the remaining lignin. The order with respect to sulphite concentration for sulphite and sulphite-AQ cooking were estimated to be 0.24 and 0.31, respectively. The activation energies of delignification of the initial phase in sulphite and sulphite-AQ pulping were 90.2 and 97.5 kJ/mole which was valid up to 30% lignin removal within the temperature range of 160°C and 175°C. AQ as a pulping additive introduced to the sulphite liquor increased the rate of delignification 1.5 times in the initial phase of delignification during the sulphite cooking process.<br>At initial pH of sulphite liquor ranging from 7 to 10, the rate of delignification in the initial phase during sulphite and sulphite-AQ cooking appears to be a second order reaction in the remaining lignin. The reaction orders with respect to sulphite concentration increases when the initial pH is below 8 and decreases when the initial pH is above 8 for both sulphite and sulphite-AQ cooking. The raw of delignificafion is dependent on the initial pH of cooking liquor and the addition of AQ.
5
Burazin, Mark Alan. "A dynamic model of kraft-anthraquinone pulping." Diss., Georgia Institute of Technology, 1986. http://hdl.handle.net/1853/5743.
Testo completo
6
Morin, Francois. "Mass transfer limitations in sulfite pulping with anthraquinone." Thesis, McGill University, 1994. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=28495.
Testo completoAbstract (sommario):
The objective of this project was to study systematically the NSSC-AQ pulping process in order to improve the penetration of anthraquinone and sodium sulfite in wood and to simulate the mass transfer and delignification processes.<br>In a heterogeneous reaction system, such as wood pulping, two main factors control the overall reaction rate: liquor penetration and chemical diffusion. As a first step, some wood characteristics affecting liquor impregnation were evaluated: 1) fiber hydraulic radius, 2) air, steam and water content, 3) wood elasticity and compressibility. Secondly, impregnation and pulping experiments were performed while varying the pre-steaming, compression and soaking time. Finally, experimental profiles were compared to computer simulated results. The two most commonly used species by the pulp industry were chosen for this study: 1) black spruce sapwood and heartwood as well as 2) trembloid poplar sapwood.<br>Impregnation of sulfite-AHQ liquor in wood blocks was simulated by a three-dimensional "Control Volume Finite Difference Method (CVFDM)". To de-couple the pressure and velocity fields, typical to convection-diffusion problems, a mass balance around individual control volume was performed using Poiseuille's capillary flow equation. The pulping kinetic differential equations were included into the CVFDM model to simulate a three-dimensional delignification pattern in the wood.<br>In general, the progression of the anthraquinone impregnation was slow and non-uniform in comparison to sulfite which penetrated rapidly and uniformly during pulping. Furthermore, delignification uniformity was related to the initial chemical profiles observed after impregnation. This confirms the importance of chemical pre-treatment for high yield pulping in order to minimize uneven delignification for chips thicker than 3mm. Results showed that, in most cases, computer simulated profiles were similar to experimental anthraquinone and sulfite impregnation patterns.
7
Gibson, Victoria. "Design, synthesis and evaluation of anthraquinone-oligodeoxynucleotide conjugates." Thesis, University of Sunderland, 1998. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.242343.
Testo completo
8
Alaparthi, Madhubabu. "Molecular Recognition Involving Anthraquinone Derivatives and Molecular Clips." Thesis, University of South Dakota, 2017. http://pqdtopen.proquest.com/#viewpdf?dispub=10285748.
Testo completoAbstract (sommario):
<p> In the past, we have demonstrated that 1,8-anthraquinone-18-crown-5 (1) and its heterocyclic derivatives act as luminescent hosts for a variety of cations of environmental and clinical concern. We report here a series of heteroatom-substituted macrocycles containing an anthraquinone moiety as a fluorescent signaling unit and a cyclic polyheteroether chain as the receptor. Sulfur, selenium, and tellurium derivatives of 1,8-anthraquinone-18-crown-5 (<b>1</b>) were synthesized by reacting sodium sulfide (Na<sub>2</sub>S), sodium selenide (Na<sub>2</sub>Se) and sodium telluride (Na<sub>2</sub>Te) with 1,8-bis(2-bromoethylethyleneoxy)anthracene - 9,10-dione in a 1:1 ratio (<b>2,3,</b> and <b>6</b>). These sensors bind metal ions in a 1:1 ratio (<b>7</b> and <b>8</b>), and the optical properties of the new complexes were examined and the sulfur and selenium analogues show that selectivity for Pb(II) is markedly improved as compared to the oxygen analogue <b>1</b> which was competitive for Ca(II) ion. </p><p> Selective reduction of <b>1</b> yields secondary alcohols where either one or both of the anthraquinone carbonyl groups has been reduced (<b> 15</b> and <b>9</b>). A new mechanism for the fluorescence detection of metal cations in solution is introduced involving a unique keto-enol tautomerization. Reduction of <b>1</b> yields the doubly reduced secondary alcohol, <b> 9. 9</b> acts as a chemodosimeter for Al(III) ion producing a strong blue emission due to the formation of the anthracene fluorophore, <b>10,</b> via dehydration of the internal secondary alcohol in DMSO/aqueous solution. The enol form is not the most thermodynamically stable form under these conditions however, and slowly converts to the keto form <b>11.</b> </p><p> Currently we are focusing on cucurbituril derivatives, also described as molecular clips due to their folded geometry used as molecular recognition hosts. We first investigated the synthesis and characterization of aromatic methoxy/catechol terminated cucurbituril units that act as hosts for small solvent molecules, such as CH<sub>2</sub>Cl<sub>2</sub>, CH<sub>3</sub>CN, DMF, and MeOH, through dual pi…H-C T-shaped interactions. We have calculated the single-point interaction energies of these non-covalent interactions and compared them to the dihedral angle formed from the molecular clip. We have also synthesized a molecular clip that contains terminal chelating phenanthroline ligands. This tetradentate ligand shows 2:3 metal:ligand binding with Fe(II) and 1:2 metal:ligand binding with Co(II) and Ni(II) cations.</p><p>
9
Lee, Young H. "Reductive biotransformation and decolorization of reactive anthraquinone dyes." Diss., Available online, Georgia Institute of Technology, 2004:, 2003. http://etd.gatech.edu/theses/available/etd-04062004-164708/unrestricted/lee%5Fyoung%5Fh%5F200312%5Fphd.pdf.
Testo completoAbstract (sommario):
Thesis (Ph. D.)--School of Electrical and Computer Engineering, Georgia Institute of Technology, 2004. Directed by Spyros G. Pavlostathis.<br>Vita. Includes bibliographical references (leaves 332-345).
10
Biasca, Karyn L. "A study of the kinetics of delignification during the early stage of alkaline sulfite anthraquinone pulping." Diss., Available online, Georgia Institute of Technology, 1989:, 1989. http://etd.gatech.edu/theses/available/ipstetd-10/biasca%5Fkl.pdf.
Testo completo
11
Lakshminarayan, Ganeshkumar. "Synthetic studies of diphenyl ether and anthraquinone natural products." [Ames, Iowa : Iowa State University], 2010. http://gateway.proquest.com/openurl?url_ver=Z39.88-2004&rft_val_fmt=info:ofi/fmt:kev:mtx:dissertation&res_dat=xri:pqdiss&rft_dat=xri:pqdiss:3403083.
Testo completo
12
Li, Zhijun. "Improving the kraft pulp yield with polysulfide and anthraquinone." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1997. http://www.collectionscanada.ca/obj/s4/f2/dsk1/tape11/PQDD_0006/MQ44022.pdf.
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13
Keskin-Schneider, Aliye. "Engineering reaction kinetics in sulfite and sulfite-anthraquinone pulping." Thesis, McGill University, 1991. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=70207.
Testo completoAbstract (sommario):
In this study, engineering reaction kinetics of sulfite and sulfite-anthraquinone pulping of black spruce wood are investigated. The considered sulfite processes are neutral-sulfite (NS), neutral sulfite-anthraquinone (NS-AQ), neutral sulfite semichemical (NSSC) and neutral sulfite semichemical anthraquinone (NSSC-AQ).<br>In preliminary studies, an experimental design was tested and optimum kinetic conditions were found so that penetration and diffusion would not be the rate-controlling steps and the amount of anthraquinone would not be reaction limiting.<br>Delignification and carbohydrate degradation rate expressions for both NS and NS-AQ pulping were developed. Research was extended to develop delignification rate expressions for NSSC and NSSC-AQ pulping. The degree of delignification was measured by determining the lignin content of the pulp. Carbohydrate content in the pulp was estimated from the difference between the pulp yield and the residual lignin in the pulp. Reaction temperature and pulping chemical concentrations were held essentially constant in all kinetic experiments. Isothermal experiments were conducted in the temperature range between 165 and 180$ sp circ$C. A concentration of 150g/l sodium sulfite with a liquor-to-wood ratio of 62 was used.<br>The effect of sulfite concentration on the delignification rate expressions for NS and NS-AQ pulping was also investigated. The rates of delignification were determined at 175$ sp circ$C over the concentration range of 54 to 154 grams sodium sulfite per liter. It was observed that the reaction rate orders with respect to sodium sulfite charge were 0.3 and 0 for the delignification rate of NS and NS-AQ pulping respectively.<br>The applicability of the H-factor for predicting pulping characteristics during NS-AQ and NSSC-AQ pulping was confirmed.<br>The role of anthraquinone as a redox catalyst in NS-AQ was investigated. It was observed that anthraquinone is reduced in NS liquor, and that the redox cycle is involved in NS-AQ pulping.
14
Li, Zhijun 1965. "Improving the kraft pulp yield with polysulfide and anthraquinone." Thesis, McGill University, 1997. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=20212.
Testo completoAbstract (sommario):
In this study, the reaction kinetics and mechanism of kraft pulping with polysulfide and anthraquinone(AQ) using black spruce wood were investigated.<br>In preliminary studies, the synergistic effect of polysulfide and AQ on pulp yield improvement was verified by different methods.<br>The identical kinetic cooking experiments were conducted for Kraft, Kraft-AQ, Polysulfide, and Polysulfide-AQ processes in the temperature range between 151 and 180ºC. It was found that the delignification rate of the PSAQ process was the fastest. The activation energies of delignification of Kraft, Kraft-AQ, Polysulfide, and Polysulfide-AQ processes were calculated as 141, 131, 142, and 131 kJ/mol, respectively. Based on obtained activation energies, the Vroom's H-factor was calculated and compared. It was also found that Kraft, Kraft-AQ, Polysulfide, and Polysulfide-AQ processes had similar activation energies for the carbohydrate degradation by 170, 174, 176, and 181 kJ/mol. Compared with the kraft process, the carbohydrate degradation rate of the PSAQ process was reduced. In addition, compared with other processes the PSAQ process had the best pulping selectivity.<br>A mechanism was proposed for the synergistic effect of polysulfide and anthraquinone on kraft pulp yield improvement based on the experimental evidence. It suggested that the synergy takes place at the beginning of heating-up period, polysulfide improves AQ penetration into wood, and therefore the maximum reduction of anthraquinone is reached earlier. The accelerated delignification helps the polysulfide to better access the hemicellulose, and that leads to more efficient stabilization of carbohydrates. In the meantime AQ retards the decomposition of polysulfide, and a higher concentration of polysulfide in the cooking liquor further prevents the degradation of carbohydrates. A redox cycle similar to that of AQ was proposed for the polysulfide.
15
Craven, Michael Robert. "The synthesis and targeting of anthraquinone anti-tumour agents." Thesis, University of Sunderland, 1988. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.278591.
Testo completo
16
Argade, A. B. "Synthesis of biologically active anthraquinone derivatives via marschalk reaction." Thesis(Ph.D.), CSIR-National Chemical Laboratory, Pune, 1988. http://dspace.ncl.res.in:8080/xmlui/handle/20.500.12252/3308.
Testo completo
17
Rowat, Alison. "Improved penetration of chemicals during chemi-mechanical pulping with anthraquinone." Thesis, McGill University, 1996. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=24070.
Testo completoAbstract (sommario):
The objectives of this work were to investigate and improve impregnation of regular (2-8mm thickness range) black spruce wood chips in CMP-AQ pulping. Impregnation and pulping experiments were performed while varying several pulping parameters. Experiments were analyzed in terms of yield, lignin content, percent screen rejects, and strength properties. The goal was to determine optimum pulping conditions that would improve chemical impregnation. Impregnation is a function of percent screen rejects: well impregnated chips have fewer rejects.<br>Cooking temperature and cooking time were held constant in all experiments at 170$ sp circ$C and 30 minutes, respectively. The liquor pH was adjusted to 7.9 and a liquor-to-wood ratio of 6:1 was used. Presteaming pressure was held constant at 138 kPa and soaking temperature was maintained isothermal at 90$ sp circ$C.<br>Process variables which can influence the chemical penetration were investigated. These are: wood chip thickness, pre-treatment agents, compression ratio, partial crushing of wood chips, and also pre-steaming and evacuation prior to chemical treatment as a possible method of entrapped air removal. Additional process parameters investigated were the concentration of pulping chemicals and dosage of AQ catalyst.<br>The advantages provided by the use of thinner wood chips, caustic pretreatment and high compression prex-impregnation were confirmed for improving chemical impregnation. The addition of SAQ catalyst to the CMP pulping process produced pulps of unusually high screened yield for given lignin content. Improvements were also observed in strength properties compared to the control cook where no SAQ was used.
18
Ijaz, Taeeba. "Anthraquinone-peptide conjugates as inhibitors of DNA transcription factor binding." Thesis, De Montfort University, 1998. http://hdl.handle.net/2086/10720.
Testo completoAbstract (sommario):
Inhibitors of Activator Protein-1 (AP-1)~ a collective term referring to dimeric transcription factors involved in mediating long term responses to signals that regulate growth control and development~ were designed and synthesised in this study. Truncated peptide sequences of 5-7 residues containing the highly conserved tri-amino acid sequence KCR found in the DNA binding domains of the AP-1 family of proteins were attached to mono-substituted anthraquinones through various amino acid type linkers. It was envisaged that these intercalator-linked peptides would have the advantage of high DNA binding with some sequence selectivity. The peptides (l:ARCKA; 2:AKCRA; 3:AKSRA; 4:AKCRNA; 5:AKCRKA; 6:AKCRNKA; 7:AKCRKRA; 8:AAKCRAA) were synthesised using solid phase peptide synthesis. The amino acid type linkers were attached to 1- chloroanthraquinone Via a nucleophilic displacement reaction and subsequently coupled to the N-terminus of the resin bound peptides using PyBOP. Characterisation of the peptides and the intercalator-linked peptides was conducted using HPLC~ MALDI-MS and 2D-NMR spectroscopy. Biophysical analysis of the peptide conjugates with DNA using fluorimetry and thermal denaturation studies indicated that the AP-I inhibitors were weak intercalators of DNA and suggested that DNA binding of these intercalator-linked peptides was govemed~ in principle, by the peptidic moiety. Electrophoretic mobility shift assays of the peptides and their respective conjugates demonstrated that the latter were more effective in displacing the AP-1 protein compared to the peptide moieties alone. These assays also showed that the peptides and conjugates bearing the sequences AKCRNA (peptide 4) and AKCRKRA (peptide 7) were particularly effective in inhibiting the AP-1 protein binding. Peptides 4 and 7 were also shown to possess an intrinsic propensity to form helical structures upon transfer to hydrophobic environments and also to interact with the DNA AP-I consensus sequence more favourably compared to peptides 1. 2. 3. 5, 6 and 8 in the circular dichroism and molecular modelling studies respectively.
19
Alam, Zohaib. "Anti-Cytomegalovirus Activity of Atanyl Blue PRL, an Anthraquinone Derivative." VCU Scholars Compass, 2013. http://scholarscompass.vcu.edu/etd/3166.
Testo completoAbstract (sommario):
Cytomegalovirus (CMV) is a significant cause of mortality and morbidity in immunocompromised patients and an important cause of birth defects if acquired in utero. The licensed CMV antivirals, ganciclovir, cidofovir and foscarnet, all target the viral DNA polymerase. For each drug prolonged use is associated with significant toxicities and development of drug resistance. None are approved for use during pregnancy. Therefore, development of new anti-CMV drugs that target different pathways would be beneficial. All herpesviruses encode an alkaline nuclease. That genetic disruption of the CMV alkaline nuclease, UL98, reduces CMV replication by 1,000-fold suggests that UL98 may be a useful target for development of novel anti-CMV drugs. Moreover, using herpes simplex virus type 1 Hsiang and Ho found that the anthraquinone emodin inhibits activity of the viral alkaline nuclease, blocks viral replication in cell culture, and reduces viral pathogeneses in a mouse model (Brit. J. of Pharm., 2008). Earlier studies also showed that anthraquinone derivatives including emodin have anti-CMV activity (Barnard et al., Antiviral Research 1992 & 1995), although the mechanism of CMV inhibition has not been further studied. We therefore sought to confirm the anti-CMV activities of emodin and related anthraquinone derivatives, to characterize their mechanisms of action, and to determine specifically if they act through inhibition of UL98. Using a luciferase-based CMV yield reduction assay emodin inhibited CMV replication (IC50 = 4.9 μM); however, that the TD50 for cytotoxicity (determined using an luciferase-based cell viability assay) was only 2-fold higher suggested that emodin may act non-specifically. Two additional anthraquinone derivatives (acid blue 40 and alizarin violet R) inhibited CMV only at high concentrations (IC50 = 238; 265 μM) that were also cytotoxic. Atanyl blue PRL, however, exhibited anti-CMV activity (IC50 = 6.3 μM) with low cytotoxicity (TD50 = 216 μM). Thus, characterization of atanyl blue PRL (impact on gene expression, GFP expression, viral spread, infectivity, time of addition studies, and inhibition of UL98 nuclease activity) should be informative. Atanyl blue PRL appears to block immediate-early gene expression and reduce early and late gene expression. Atanyl blue PRL also blocked GFP expression, reduced viral spread, and also lowered the infectivity of CMV. Finally, atanyl blue PRL inhibits UL98 alkaline nuclease activity at an IC50 of 5.7 μM. This suggests that atanyl blue PRL may inhibit CMV through inhibition of UL98. Thus, atanyl blue PRL represents a novel class of anti-herpesvirals and provides a lead structure for structure based drug discovery.
20
Aquino, Angela Marie. "The Synthesis and Photochemistry of Anthraquinone-2,6-disulfonyl-beta-cyclodextrin." W&M ScholarWorks, 1989. https://scholarworks.wm.edu/etd/1539625517.
Testo completo
21
Holmes, Jennifer Jane. "Metabolism and mechanisms of action of novel pyrazoloacridone and anthraquinone cytotoxic agents." Thesis, University of Strathclyde, 1995. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.249821.
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22
Pham, Thi Tham. "A cycloaddition approach to substituted anthraquinone systems as potential antitumor agents." Thesis, University of Ottawa (Canada), 1996. http://hdl.handle.net/10393/9769.
Testo completoAbstract (sommario):
In the cycloaddition approach towards the synthesis of the substituted anthraquinone derivative 8 as a potential antitumor agent, it was found that the tricyclic core of this target analogue could be generated by an intramolecular Diels-Alder reaction. The Diels-Alder precursor 34 was successfully synthesized starting from 3-methyl benzyl alcohol, metha-crolein and (2Z)-2-(ethenyl)-3-iodo-1- (p-methoxybenzyloxy)-2-propene; it readily underwent cycloaddition at approximately 40$\sp\circ$C to generate a cis-fused ring system 35. The stereochemistry of the cycloaddition product was unambiguously determined by X-ray structure of crystalline 41. Stereo-selective epoxidation of the ring C double bond with m-chloroperoxybenzoic acid was achieved for diol 48, where the functionality at C2 was a hydroxyl group. The synthesis of anthraquinone derivative 47b is also described.* ftn*Please refer to the dissertation for diagrams.
23
Jackson, Beckford Shirlene R. "Biophysical Characterization of the Binding of Homologous Anthraquinone Amides to DNA." Digital Archive @ GSU, 2012. http://digitalarchive.gsu.edu/chemistry_diss/70.
Testo completoAbstract (sommario):
The synthesis of four homologous anthraquinones (AQ I-IV) bearing increasing lengths of polyethylene glycol (PEG) side chains and their binding to AT- and GC-rich DNA hairpins are reported. The molecules were designed such that the cationic charge is at a constant position and the ethylene glycol units chosen to allow significant increases in size with minimal changes in hydrophobicity. The mode and affinity of binding were assessed using circular dichroism (CD), nuclear magnetic resonance (NMR), surface plasmon resonance (SPR), and isothermal titration calorimetry (ITC). The binding affinity decreased as the AQ chain length increased along the series with both AT- and GC-rich DNA. ITC measurements showed that the thermodynamic parameters of AQ I-IV binding to DNA exhibited significant enthalpy-entropy compensation. The enthalpy became more favorable while the entropy became less favorable. The correlation between enthalpy and entropy may involve not only the side chains, but also changes in the binding of water and associated counterions and hydrogen bonding.
The interactions of AQ I-IV with GC-rich DNA have been studied via molecular dynamics (MD) simulations. The geometry, conformation, interactions, and hydration of the complexes were examined. As the side chain lengthened, binding to DNA reduced the conformational space, resulting in an increase in unfavorable entropy. Increased localization of the PEG side chain in the DNA groove, indicating some interaction of the side chain with DNA, also contributed unfavorably to the entropy. The changes in free energy of binding due to entropic considerations (-3.9 to -6.3 kcal/mol) of AQ I-IV were significant.
The kinetics of a homologous series of anthraquinone threading intercalators, AQT I-IV with calf thymus DNA was studied using the stopped-flow. The threading mechanisms of the anthraquinones binding to DNA showed sensitivity to their side chain length. Fitting of the kinetic data led to our proposal of a two step mechanism for binding of AQT I, bearing the shortest side chain, and a three step mechanism for binding of the three longer homologs. Binding involves formation of an externally bound anthraquinone-DNA complex, followed by intercalation of the anthraquinone for AQT I-IV, then isomerization to another complex with similar thermodynamic stability for AQT II-IV.
24
Kan, Yongzhi. "Probing the structural and electronic properties of deoxyribonucleic acids with anthraquinone photonucleases." Diss., Georgia Institute of Technology, 1999. http://hdl.handle.net/1853/30475.
Testo completo
25
Zhan, Bohan. "Synthesis and Use of Amyl Anthraquinone for the Production of Hydrogen Peroxide." Thesis, Queen's University Belfast, 2010. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.517621.
Testo completo
26
Whan, Renee Megan. "The interactions of platinum-anthraquinone complexes with cells and their intracellular components." Thesis, The University of Sydney, 2007. https://hdl.handle.net/2123/28082.
Testo completoAbstract (sommario):
In this study, we have explored how cisplatin, anthraquinones and platinum—
anthraquinone complexes interact with cells and their intracellular components.
Emphasis has been placed on the interactions the complexes have with DNA, the
mechanisms by which they are trafficked into the cell and nucleus to access DNA,
and how in turn this affects the cytotoxicity they induce in sensitive and resistant
carcinoma cells, as well as healthy cells. The anthraquinone complexes that have
been studied include; 103, 1,5C3, Pt(dien)103, Pt(dien)1,5C3 and Pt1C3
(Appendix 1).
Examination of the affinity and specificity the complexes had for DNA, involved the
use of UV-spectrophotometric and fluorometric titrations as well as two
dimensional NMR. Titration of the complexes with DNA revealed hypochromic and
bathochromic shifts in the absorption spectra, indicative of intercalation into DNA.
The affinity for DNA was found to follow the order: 103 < 1,5C3 < Pt(dien)1C3 <
Pt(dien)1,5C3, with Kapp values ranging from 1.4 x 104 to 5.5 x 105 M", indicating
that attachment of the Pt(dien) moiety increased the affinity the anthraquinones
have for DNA and that a threading intercalator has greater affinity for DNA than a
classical intercalator.
The DNA binding properties were also examined through monitoring the emission
spectra of the anthraquinones. Enhancement of fluorescence intensity was
observed for Pt(dien)103, 1,503 and Pt(dien)1,503 and all anthraquinones
exhibited a hypsochromic shift in their emission maxima. The studies revealed that
the anthraquinones are involved in more than one DNA binding mode over the
DNA concentration range studied. Furthermore it was found that changes in
emission profile of a chromophore may provide insight into sequence selectivity
and/or whether a complex is intercalated or localised within the minor groove.
The NMR experiments conducted on Pt(dien)1C3 and TGGCCA showed that the
anthraquinone intercalated from the minor groove into the pyrimidine-purine
sequences at each end of the hexamer. The intercalation of the complex resulted
in the the hexamer retaining its 8- conformation and the Pt(dien) moiety residing in
the minor groove in near proximity to G3.
The cytotoxicity of the complexes was examined using the MTT assay in a number
of cell lines, including; sensitive and resistant carcinoma cells and healthy cells. In
A2780 ovarian carcinoma cells the |Cso values followed the trend cisplatin < 1,503
< 1C3 << Pt(dien)1,5C3 << Pt(dien)1C3 This trend was seen to differ between cell
lines. The cell death pathway by which the complexes induced cytotoxicity in
A2780 cells was examined through the use of Hoechst 33342, propidium iodide
and confocal microscopy. Cisplatin and Pt1C3 were seen to trigger apoptosis,
while 1,5-subsituted anthraquinones induce necrosis.
The accumulation and intracellular distribution of the complexes was examined via
two means; as a function of the intercalator, utilising the intrinsic fluorescence of
the anthraquinone and using confocal microscopy, and as a function of the
platinum attachment by quantifying cellular and nuclear platinum content though
GF-AAS. In addition, the inhibitors antimycin, monensin, ouabain and wheat germ
agglutinin were employed in both studies to reveal some of the mechanisms
responsible for the intracellular distribution in sensitive and resistant carcinoma
cells. Several results and conclusions came from these studies. Firstly,
accumulation of the complexes is related to glycoproteins at the plasma
membrane and/or intracellularly, but this interaction does not occur in cisplatin
resistant A2780 cells. Secondly, organelles of the vacuolar system have roles in
endocytosis, exocytosis and/or sequestration of the complexes and these
pathways are altered in cisplatin resistant A2780 cells. Thirdly, the nuclear
accumulation of cisplatin, Pt1C3, Pt(dien)1C3 and Pt(dien)1,5C3 does not occur
via interaction with nuclear destined proteins and subsequent translocation
through the nuclear pore complex, irrespective of whether the cell line is sensitive
or resistant to cisplatin. Lastly, the cellular pathway of the fluorophore and of
platinum is not always the same, indicating that cleavage of platinum groups
occurs intracellularly.
27
Hobson, Debra Kay. "A natural source of anthraquinone dye intermediates : production and identification of microbial anthraquinones, an environmentally friendly method of producing dye intermediates, and their conversion to textile dyestuffs." Thesis, University of Bradford, 1995. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.566824.
Testo completoAbstract (sommario):
An environmentally friendly route to anthraquinone dyes has been developed by exploiting the anthraquinone biochromophores produced by microorganisms. An extensive screen of biochromophore producers, including species of Pyrenophora, Trichoderma, Drechslera, Phoma and Curvularia, was undertaken. The biochromophores were extracted from the mycelia with acetone and characterised by means of TLC, HPLC, GLC, mass spectrometry and UV /vis spectrophotometry. Most of the organisms produced anthraquinones unsuitable for conversion to anthraquinone dyes/dye intermediates. Problems included the anthraquinones being produced only at low temperatures, being too complex for dye conversion, possessing substitutions in the P-position, or being produced association with fatty material or as mixtures and thus not of high enough purity for dye conversion. Two strains of Curvularia, C. lunata and C. ramosa produced cynodontin (1,4,5,8- tetrahydroxy-3-methylanthraquinone) of the required purity although initial yields were poor and associated with melanin. Strain selection and manipulation of the culture medium resulted in elimination of melanin and cynodontin yields of up to l.0g dm-3. The culture medium developed contains nitrate as the nitrogen source and 6% sucrose as the carbohydrate source. Zinc was shown to influence the balance between anthraquinone and melanin production whilst a cycle of l2h white light/l2h respite from light produced a lO fold increase in cynodontin yield. The optimum pH was pH 7.0 whilst a temperature of 28°C and aeration of around 4 dm3 minot with impeller speed of 400rpm was preferred. Cynodontin, once acceptable as a dyestuff in its own right, no longer has the washfastness required for modern detergents. However, as an intermediate, cynodontin requires only a few simple chemical steps to produce a blue biodye which is an analogue of Disperse Blue 7 and a green biodye which is an analogue of Acid Green 28. Both biodyes appear brighter than their chemically synthesised analogue and also possess slightly better fastness properties than the conventional dyes when applied to knitted polyamide.
28
Reed, Gregg Arthur. "Nucleophilicity of hydroxide, hydrosulfide, and anthrahydroquinone ions toward saturated and unsaturated carbon centers at high temperatures." Diss., Georgia Institute of Technology, 1988. http://hdl.handle.net/1853/5505.
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Espensen, George Max. "Towards the total synthesis of anthraquinone antifungal agents Sch 47554 and Sch 47555." Thesis, Imperial College London, 2011. http://hdl.handle.net/10044/1/9197.
Testo completoAbstract (sommario):
The total synthesis of Sch 47554 (1) is the focus of this project, with the intention of using two aryne-furan cycloaddition reactions to efficiently build the anthraquinone core of the molecule. The first is intermolecular with furan, which is then elaborated with a C-aryl glycosidation reaction. The second is intramolecular between 5 and 6 where the two fragments are linked by a disposable tether connected through the oxygen functionalities, as demonstrated in 2. This ensures the correct angularly-fused regiochemistry of the aryne-furan cycloaddition. [Molecular structure diagrams appear here. To view, please open pdf attachment]. To this end suitable precursors have been examined. After several unsuccessful attempts at making various suitably-functionalised precursors, double aryne precursor 8 was synthesised and converted into naphthol 10. This was successfully glycosylated, but this substrate is less flexible later in the synthesis than another substrate developed, 9. This was converted into naphthol 10 and the glycosidation is currently being optimised. Elsewhere in the group furan 6 has been synthesised. These systems are appropriate for completing the synthesis of 1. [Molecular structure diagrams appear here. To view, please open pdf attachment].
30
Conrad, Catleen. "Bernhard-von-Cotta-Preis 2014: Reinigung und Charakterisierung von zwei Peroxidasen DypA und DypB aus Rhodococcus opacus 1CP." Technische Universitaet Bergakademie Freiberg Universitaetsbibliothek "Georgius Agricola", 2016. http://nbn-resolving.de/urn:nbn:de:bsz:105-qucosa-211185.
Testo completoAbstract (sommario):
Das Bodenbakterium Rhodococcus opacus 1CP ist für sein Potenzial bekannt, organische Schadstoffe abzubauen. In dieser Studie lag der Fokus auf zwei Genprodukten, den farbstoffabbauenden Peroxidasen DypA und DypB, welche unter Anwendung von Klonierungs- und Expressionsstrategien mit hohen spezifischen Aktivitäten in reiner Form gewonnen werden konnten. Eine umfassende biochemische Analyse zeigte, dass beide Enzyme in der Lage sind, Farbstoffe unterschiedlicher Klassen, insbesondere jedoch, die als schwer abbaubar geltenden Anthraquinone, strukturell anzugreifen. Damit stellen sie lohnenswerte enzymatische Systeme zum Abbau toxischer Farbstoffe beispielsweise in industriellen Abwässern dar.
31
Rabinowitz, Daniel Joshua. "Electrochemical Studies of Substituted Anthraquinones." Digital Archive @ GSU, 2008. http://digitalarchive.gsu.edu/chemistry_theses/15.
Testo completoAbstract (sommario):
Electrochemical potentials of a series of anthraquinone derivatives were studied in both aqueous solution and acetonitrile. The long term goal of this work was to find derivatives which could be reduced easily for studies of photoinduced electron transfer in DNA. Our immediate goal was to find the substitution group that gave the least negative redox potential value. Of all derivatives studied, the anthraquinone imides as a class had the least negative redox potentials, in the range of -0.600 to -0.550 V vs. SCE. One of the anthraquinones studied, one derivative (deoxyadenosine conjugated with an ethynyl linker to an anthraquinone with two ester substituents) was also in this range. A study of a series of anthraquinones conjugated with ethynyl and ethanyl linkers showed that the ethynyl linker was more effective than the ethanyl linker in lowering the redox potential of anthraquinone.
32
Umeweni, Chiko. "Synthesis of Internally Linked Carbazole DNA Oligomers: A Potential Monitor for Charge Transfer in DNA Studies." Thesis, Available online, Georgia Institute of Technology, 2005, 2005. http://etd.gatech.edu/theses/available/etd-07052005-161648/.
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Palacios, Sara. "Decolourization of azo and anthraquinone dyes by mean of microorganisms growing on wood chips." Thesis, Växjö University, School of Technology and Design, 2009. http://urn.kb.se/resolve?urn=urn:nbn:se:vxu:diva-5168.
Testo completoAbstract (sommario):
<p>Reactive Black 5 and Procion Red MX 5B, an azo and anthraquinone dye repectively were decoulorized by mean of microorganisms growing on wood chips. The process consisted of three reactors, two anaerobic reactors and one aerobic reactor. The anaerobic process was used in order to make it possible to break the nitrogen bond of the azo group, (-N=N-) and the aerobic one to increase the possibility for the degradation of possible intermediates. After pumping wastewater through the system it was shown that mixtures or Reactive Black 5 and Procion Red MX 5B were efficiently decolourised at 50 mg/l as well as 200 mg/l of each of the dyes.</p><p><strong> </strong></p>
34
Vidal, Marie-Hélène. "Influence d'un champ magnétique sur les recombinaisons géminées : étude de systèmes, anthraquinone-donneurs d'hydrogène." Paris 11, 1987. http://www.theses.fr/1987PA112265.
Testo completoAbstract (sommario):
Cette étude porte sur l'influence d'un champ magnétique sur l'orientation de réactions chimiques passant par l'intermédiaire d'une paire de radicaux libres à spins corrélés (radicaux en "cage"). Dans la première partie, nous avons exposé la théorie dite de la "paire de radicaux" permettant d'interpréter l'évolution de tels systèmes : les mécanismes de passage singulet-triplet et les différentes interactions à l'intérieur des paires ainsi que le traitement quantique de résolution du système. La technique utilisée pour cette étude est la photolyse laser nanoseconde (absorption) qui est décrite dans la deuxième partie. Dans la troisième partie, nous présentons les résultats expérimentaux obtenus sur les systèmes Anthraquinone (AQ) - Donneurs d'hydrogène :-nous montrons qu'il n'y a pas d'effet de champ sur de tels systèmes en solution homogène même à viscosité élevée, et donnons les spectres d'absorption des différents intermédiaires de réaction. -Par contre, nous mettons en évidence un effet de champ important lorsqu’AQ est confinée dans des micelles de SDS (HS), celles-ci jouant le rôle de donneur d'hydrogène. Nous obtenons le spectre d'absorption du radical semi-quinone AQH· en "cage" et proposons un mécanisme pour sa disparition vers les espèces AQH-S et AQH2. -L'addition du 9,10 Dihydroanthracene (DH2) à l'intérieur de la micelle, près de AQ permet, par la création de paires (AQH· DH·) peu mobiles d'augmenter l'effet de champ. -Des paires de radicaux immobilisées par une matrice protéique ont également été étudiées dans des centres réactionnels de bactéries photosynthétiques : dans ce cas, le champ de demi-effet est déplacé vers les champs faibles par rapport aux systèmes précédents<br>This study is devoted to magnetic field effects on chemical reactions which involve a radical pair with correlated spins (radicals in a "cage"). In the first part, the radical pair theory is described: mechanisms of singlet-triplet mixing, the different interactions inside the pair and a quantum mechanical treatment of the radical pair. The details of the experimental method (nanosecond laser flash photolysis) are reported in the second part. In the third part are shown experimental results obtained on Anthraquinone (AQ) - Hydrogen donors systems:There is no magnetic field effect in homogeneous solution even at a high viscosity. The absotption spectra of the different reaction intermediates are obtained. However a magnetic field effect is put forward when AQ is introduced in SDS micelles which are hydrogen donors. The absorption spectrum of the AQH· semi-quinone radical in "cage" is shown and a mechanism is proposed for its disappearance to generate the AQH-S and AQH2 species. The addition of 9, 10 Dihydroanthracene (DH2) inside the micelle near AQ induces an increase of the magnetic field effect by creation of (AQH· DH·) pairs which diffuse slowly. Fixed radical pairs in a protein matrix were studied in reaction centers of photosynthetic bacteria: in that case, the half-effect field is shifted to low fields when compared to the precedingly described systems
35
Vidal, Marie-Hélène. "Influence d'un champ magnétique sur les recombinaisons géminées étude de systèmes, anthraquinone-donneurs d'hydrogène /." Grenoble 2 : ANRT, 1987. http://catalogue.bnf.fr/ark:/12148/cb37610590r.
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Lo, Anthony Tin Shing. "Novel polyamide amidine anthraquinone platinum(II) complexes for enhancing DNA binding and tumour penetration." Thesis, The University of Sydney, 2014. http://hdl.handle.net/2123/12469.
Testo completoAbstract (sommario):
A set of aminoalkylamine substituted anthraquinones (AAQs) was successfully synthesised by aminating 1- or 1,5-chloroanthraquinones in a single reaction step. These substituted anthraquinones, 1C3 or 1,5C3, were tethered to minor groove binding polyamides with between 1 - 3 N-methyl pyrrole units (Py) to produce a library of Py-AAQ compounds. It was envisaged that these compounds could improve cytotoxicity through bimodal damage to DNA relative to the individual polyamide or AAQ moieties. A set of py-AAQ platinum complexes was also successfully synthesised by a platinum-mediated alkylamine to nitrile addition. The additional conjugation of a platinum nitrile complex to Py-AAQ conjugates was predicted to generate agents that are more cytotoxic than the Py-AAQ conjugates by damaging DNA via a minor groove binding (MGB)-intercalation-platination mechanism. All newly synthesised Py-AAQs and associated imino coordinated platinum(II) complexes were examined for cytotoxic activity in DLD-1 colon and MDA-MB-231 breast carcinoma cells using MTT assays. Tethering polyamides to AAQs was found to diminish the activity of the anthraquinones, while the platinum(II) conjugates exhibited moderate cytotoxicity in both carcinoma cell lines (IC50 16–30 µM). Subcellular distribution studies showed that the inactive Py-AAQ compounds tended to be localised in the lysosomes or pinocytic vesicles. Three-dimensional spheroid tumour penetration studies showed that Py-AAQ conjugates can be taken up slowly by cells enabling deeper penetration (60-100 µm) into the tumour than either of the individual 1C3 or 1,5C3 moieties (20-30 µm). Subcellular distribution studies indicated that the platinum(II) conjugates were localised in the nucleoli. The 1C3 tethered platinum complexes were found to have a binding specificity of 3’-(A/T)GTA-5’ nucleotide sequence using a polymerase stop assay whereas the 1-3py-1,5C3 tethered platinum complexes were found to have a similar binding specificity as cisplatin.
37
Pettersson, Susanne. "Biochemistry of topoisomerase inhibtion and cellular mechanisms of anthraquinone-amino acid conjugates in vitro." Thesis, Edinburgh Napier University, 2004. http://researchrepository.napier.ac.uk/Output/4160.
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Abou-Elkhair, Reham A. I. "Synthesis of anthraquinone derivatives and their conjugates with 2'-deoxynucleosides as new probes for electron transfer studies in DNA." unrestricted, 2008. http://etd.gsu.edu/theses/available/etd-07182008-154942/.
Testo completoAbstract (sommario):
Thesis (Ph. D.)--Georgia State University, 2008.<br>Title from file title page. Thomas L. Netzel, Dabney W. Dixon, committee co-chairs; David Boykin, Jerry Smith, committee members. Electronic text (250 p. : ill. (some col.)) : digital, PDF file. Description based on contents viewed Nov. 20, 2008. Includes bibliographical references.
39
Ma, Jiani, and 马佳妮. "Time-resolved spectroscopic studies of meta methyl activation reaction of selected benzophenone and anthraquinone derivatives." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2013. http://hdl.handle.net/10722/196012.
Testo completoAbstract (sommario):
Femtosecond time-resolved transient absorption (fs-TA), nanosecond time-resolved transient absorption (ns-TA), and nanosecond time-resolved resonance Raman spectroscopy (ns-TR3) methods were used to study the behaviors of the transient intermediates involved in the photophysical and photochemical processes of 3-methylbenzophenone (3-MeBP), 3-(hydroxymethyl)benzophenone (m-BPOH), and 2-(1-hydroxyethyl) 9,10-anthraquinone (2-HEAQ). A particular focus of this work was to study
the unusual meta methyl activation reactions of these compounds in
water-containing solutions. Density functional theory (DFT) calculations were
conducted to help make assignments of the observed experimental transient
species and to better understand the reaction mechanisms. First, the
photophysical and photochemical reactions of m-BPOH were investigated in
selected solvents. In acetonitrile (MeCN) the formation of the triplet state of
m-BPOH, (denoted as (m-BPOH)3 ), was detected via an intersystem crossing
(ISC). In 2-propanol (IPA), (m-BPOH)3 abstracted a hydrogen atom from the
solvent molecule to form an aryl ketyl radical. In an acidic mixed aqueous
solution at pH 2, the photoredox reaction appeared to be the predominant
reaction. In a more acidic aqueous solution with [H+] =1.0 M, the photoredox
reaction faced some competition from the overall photohydration reaction.
Second, the photophysical and photochemical reactions of 2-HEAQ in MeCN,
IPA, and neutral, acid and basic aqueous solutions were studied. The ISC
process of 2-HEAQ took place in MeCN with generation of the triplet excited
state species of 2-HEAQ, (2-HEAQ)3. In IPA solvent, (2-HEAQ)3 underwent a
hydrogen abstraction with the solvent. A photoredox reaction takes place via
an initial protonation process of the AQ group that is followed by deprotonation of the methylene C-H bond in aqueous solutions within a pH
range from 2 to 10. Under a stronger acidic aqueous condition with [H+] =1.0
M, the photohydration reaction becomes the major reaction. In strong basic
solutions (pH=12) only ISC was observed to take place. The unusual
photoredox reaction takes place via protonation of the carbonyl oxygen first
followed by deprotonation of the C-H bond in the side chain for both m-BPOH
and 2-HEAQ. The protonation of the excited carbonyl oxygen group has been
widely studied. On the other hand, the deprotonation of methylene C-H bond
is unusual. Therefore, this photoredox reaction for m-BPOH and 2-HEAQ is
termed as a meta methyl activation reaction. Third, the photophysical and
photochemical reactions of 3-MeBP were explored and compared to those of
4-methylbenzophenone (4-MeBP). This work found that 3-MeBP and 4-MeBP
exhibit similar behaviors with m-BPOH and 2-HEAQ in MeCN and IPA. In
MeCN, both 3-MeBP and 4-MeBP undergo an efficient ISC process producing
triplet excited state species, (3-MeBP)3 and (4-MeBP)3, respectively. In IPA,
the (3-MeBP)3 and (4-MeBP)3 intermediates were quenched by the hydrogen
abstraction reaction with the solvent. In acidic aqueous solutions (pH 2), the
protonated carbonyl oxygen species (3-MeBPH+)3 and (4-(MeBPH+)3 are
directly observed by fs-TA spectra. In the case of 4-MeBP, a photohydration is detected and the m-(4-MeBPH2O)3 and o-(4-MeBPH2O)1 species are
observed. In contrast, an unusual meta methyl activation reaction is observed
for 3-MeBP. In a stronger acid aqueous solution ([H+] =1.0 M) the meta
methyl activation reaction becomes the predominant reaction.<br>published_or_final_version<br>Chemistry<br>Doctoral<br>Doctor of Philosophy
40
Haruna, Ken-ichi. "Regulation and evaluation of long distance one-electron oxidation in DNA by anthraquinone-photoinjected hole." 京都大学 (Kyoto University), 2006. http://hdl.handle.net/2433/136130.
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Yang, Xiaotian. "Interfacing spectrophotometry to process liquors applications to kraft pulping." Doctoral thesis, KTH, Chemistry, 2002. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-3428.
Testo completoAbstract (sommario):
<p>This thesis summarizes the outcome of work performed withthe objective to contribute to the knowledge and development ofthe kraft cooking process using spectrophotometricinterfaces.</p><p>In kraft cooking, it is desirable to maximize the removal oflignin in the cook without loss of pulp strength. Theselectivity can be improved by exchanging some of the hydrogensulfide ion in the white liquor for polysulfides. Paper Ipresents a spectrophotometric method for in-line monitoring ofthe electrochemical production of polysulfide using anATR-probe for the UV-Vis range. A linear relation existsbetween the ATR-probe response and the concentration ofabsorbing species. Thus the process can be followed by simplemonitoring of a few wavelengths.</p><p>A spectrophotometric monitoring system using a durableNafion ionomer membrane interface for continuous on-linemeasurement of sulfide and dissolved lignin during kraftcooking has previously been developed by our group. In paperII, the permeation of low molecular weight anions from liquorshaving high ionic strengths through a membrane in Na+ form hasbeen studied. A general relation between penetration and ionsize approximated by molecular weight has been established. Thepenetration of different anions can be explained as a diffusionthrough the winding membrane channels. Further the differentanions transport independently without being interfered by thesample matrix.</p><p>In light of this validation, we applied the membraneinterface to the determination of anthraquinone-2-sulfonate(AQ-S) in alkaline pulping liquor. In paper III, a simple andrapid spectrophotometric method was developed and implementedon real samples. Interferences from other compounds penetratingthe membrane were minimized by reduction of the penetrated AQ-Sand measurement at 520 nm. This method is quick and can be usedon-line. Further, we extended the method to determination ofanthraquinone (AQ) in pulping liquor (paper IV). Although AQ isregarded as insoluble, it was found that the apparentsolubility of AQ in alkaline solutions increases considerablyin the presence of lignin, reaching 0.14 g/L at 90 oC. Thismakes the calibration of AQ possible. Time-resolvedmeasurements of dissolved AQ in 3 kraft-AQ pulping processeswere performed.</p><p>The results show that the membrane has great potential aspart of a selective interface in applications where theconcentrations of small anions are to be monitored in mediawith high ionic strength.</p><p>Keywords: Kraft cooking, On-line, Sulfide, Lignin,Polysulfide excess sulfur, Anthraquinone-2-Sulfonate (AQ-S),Anthraquinone (AQ), Nafion Membrane, UV-Vis, ATR-probe,Spectrophotometric.</p>
42
Sims, Mark T. "A combined experimental and computational study of anthraquinone dyes as guests in nematic liquid crystal hosts." Thesis, University of York, 2015. http://etheses.whiterose.ac.uk/11464/.
Testo completoAbstract (sommario):
A 1,5-diphenylythio-substituted anthraquinone, two 1,5-diphenylamino-substituted anthraquinones, and two 2,6-diphenyl-substituted anthraquinones have been studied in the context of the dyes as guests in nematic liquid crystal hosts, using a range of experimental and computational techniques. UV-visible absorption spectroscopy showed that the dyes exhibit visible transitions at a range of wavelengths, and polarised UV-visible absorption spectroscopy of aligned samples of the dyes in the nematic host E7 yielded a range of dichroic order parameters. Redox potentials of the dyes obtained by cyclic voltammetry and spectroelectrochemistry showed significantly more variation between the oxidation potentials than the reduction potentials, and a correlation between colour and redox properties was shown. Visible electronic transitions were calculated by time dependent density functional theory, and order parameter contributions determined from angles between the calculated transition dipole moment orientations and the minimum moment of inertia axes matched the trend in experimental dichroic order parameters. Molecular dynamics simulations of the dyes in E7 showed little variation in calculated orientational order parameters of the minimum moment of inertia axes of the dyes. The trend in experimental dichroic order parameters was replicated by calculated values, determined by combining the calculated orientational order parameters with the contributions from the transition dipole moment orientations. An assessment of various molecular alignment axes of the dyes indicated that the surface tensor model provided the most aligned axes of those tested, and improved the match with experimental dichroic order parameters. Incorporating dye flexibility into the calculations resulted in a further improvement in the match with experiment. Isolated molecule simulations combined with a mean field approach enabled the calculation of order parameters at a reduced computational expense. Application of this approach to a variety of dyes from different classes demonstrated a generally good match with reported experimental alignment trends.
43
Pankewitz, Florian. "Unusual natural products in insects molecular and chemical analyses of anthraquinone origin in Galerucini leaf beetles /." kostenfrei, 2007. http://www.diss.fu-berlin.de/2007/20/index.html.
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Schmidt, Daniel [Verfasser], Ulrich Sigmar [Gutachter] Schubert, and Philipp [Gutachter] Adelhelm. "Anthraquinone based redox-active polymers for organic batteries / Daniel Schmidt ; Gutachter: Ulrich Sigmar Schubert, Philipp Adelhelm." Jena : Friedrich-Schiller-Universität Jena, 2016. http://d-nb.info/1177610922/34.
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Niner, Megan Denise. "The Effectiveness of 9, 10 Anthraquinone as a Repellent to Protect Oilseed Sunflower from Blackbird Depredation." Thesis, North Dakota State University, 2014. https://hdl.handle.net/10365/27369.
Testo completoAbstract (sommario):
Across the Prairie Pothole Region of North America, blackbirds (Icteridae) cause millions of dollars in damage to sunflower crops annually, but effective methods to prevent or limit blackbird damage to sunflower crops are lacking. I tested two repellents (Avipel and AV2022, both with active ingredient 9, 10 anthraquinone) under application conditions that would be appropriate for large-scale, sunflower farming in two consecutive years. In 2012, I conducted daily avian point counts and weekly crop damage surveys to assess blackbird use of, and damage to, plots of sunflowers were sprayed with Avipel or left unsprayed (i.e., control). In 2013, I placed six netted enclosures (each containing three male red-winged blackbirds, <italic>Agelaius phoeniceus</italic>, approximately 40 mature sunflowers and trays with cracked corn and water) in a plot of sunflower treated with AV2022 applied by a ground sprayer, and six netted enclosures (each containing three male red-winged blackbirds approximately 40 mature sunflowers and trays with cracked corn and water) in an adjacent plot of sunflower left untreated (i.e., control). Results from 2012 indicate that blackbird use of, and damage to, sunflower plots did not vary with treatment of Avipel. Results from 2013 indicate that enclosures in the AV2022 treated plot had sunflower plants with significantly more seed loss and significantly less cracked corn consumed from food trays than enclosures in the untreated (i.e., control) plot. I conclude that 9, 10 anthraquinone does not significantly reduce blackbird damage to sunflower crops when applied using typical methods for pesticides in large-scale, commercial agriculture.<br>National Sunflower Association<br>U.S. Department of Agriculture Wildlife Services’ National Wildlife Research Center<br>North Dakota State University (NDSU)
46
Ezenwafor, E. I. I. "The synthesis and properties of derivatives of 1-amino-4-hydroxy anthraquinone : The synthesis of thiolated derivatives of 1-amino-4-hydroxy anthraquinone and a study of their application, dyeing and fastness properties on synthetic-polymer fibres." Thesis, University of Bradford, 1985. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.371494.
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Eggers, Paul Kahu Chemistry Faculty of Science UNSW. "Probing the electrochemical double layer: an examination of how the physical and electrical structure affects heterogeneous electron transfer." Publisher:University of New South Wales. Chemistry, 2008. http://handle.unsw.edu.au/1959.4/41285.
Testo completoAbstract (sommario):
In this research the environmental effects related to the position of a redox moiety with the electrochemical double layer were studied. This project was made possible with the synthesis of a series of lengths of ferrocene derived alkanethiols, a series of lengths of ferrocene derived norbornylogous bridges and a series of lengths of anthraquinone derived norbornylogous bridges. The series of ferrocene derived alkanethiols were used to study the effect of gradually varying the polarity of the self-assembled monolayers (SAMs) surface on the standard electron transfer rate constant and formal potential. This was achieved by varying the portion of hydroxyl to methyl terminated alkanethiol diluent in the SAM preparation step. It was found that the formal potential increased with a decreasing proportion of hydroxyl terminated diluent and increasing length of the diluent. For pure hydroxyl terminated diluent the formal potential was relatively independent of length. It was found that the rate constant increased for short alkane chain lengths with decreasing proportion of hydroxyl terminated diluent. However, it decreased in magnitude with long alkane chain lengths for low proportions of hydroxyl terminated diluent. The norbornylogous bridges were shown to stand proud above the diluent with a similar tilt angle as the alkanethiol diluent. The ferrocene derived norbornylogous bridges showed hydroxyl terminated monolayers had a slower rate constant then methyl terminated diluents independent of length and that it is highly probable that an alkane bridged redox moiety is located very close to the surface of the monolayer. SAMs were created with the ferrocene of the ferrocene derived norbornylogous bridges located at various heights above the monolayers surface. This was done by using various lengths of hydroxyl terminated diluent. It was found that the rate constant and the formal potential decreased with height above the surface. Interfacial potential distribution was used to account for this and to estimate a ??true?? formal potential. The anthraquinone derived norbornylogous bridges were tested at various pH values and heights above the surface. It was found that an accurate estimate for the electron transfer mechanism can not be made for surface bound species due to the effects of interfacial potential distribution. They demonstrated a novel technique for estimating the point of zero charge of the electrode.
48
Shrestha, Jaya P. "Synthesis, Structure-Activity Relationship Study, and Mode of Action Study of 1,4-Naphthoquinone Based Anticancer and Antimicrobial Agents." DigitalCommons@USU, 2016. https://digitalcommons.usu.edu/etd/4925.
Testo completoAbstract (sommario):
Synthesizing bioactive small molecules by structural modification of 1,4-naphthoquinone was the primary goal of this research. Several bioactive compounds with anticancer, antifungal, and antibacterial activities were synthesized. All the synthetic protocols were optimized in such ways that do not require cumbersome purification.
First, a new protocol for the synthesis of NQM111 was developed. NQM111 is a highly potent anticancer agent developed in our laboratory, but the old protocol does not provide enough quantity for in vivo study. Therefore, a new safe and improved method was developed which provides enough quantity for in vivo study.
The second project involves the synthesis of 1,4-naphthoquinone conjugated with an aromatic group. These compounds are a highly potent anticancer agent with ~8-fold selectivity towards cancer cell lines than the non-cancer cell line. A mode of action study of this compound was identified, and it was observed that these compounds generate reactive oxygen species,which triggers apoptosis.
The final project involves the synthesis of 1,4-naphthoquinone based antifungal, and antibacterial compounds. These compounds are multi-cationic in nature with a hydrophobic tail. Six different analogs with varying hydrophobic tails were synthesized and tested for their antibacterial and antifungal activity. These compounds showed excellent activity against wide range of fungi including resistant strains.
49
Ford, Lauren Louise. "Chemical analysis and elucidation of anthraquinone and flavonoid type compounds with applications to historical artefacts and sustainability." Thesis, University of Leeds, 2017. http://etheses.whiterose.ac.uk/18502/.
Testo completoAbstract (sommario):
This thesis describes the effects of different solvents have on the extraction profile of natural dyes from dye plants: madder, weld, golden rod, and chamomile. HPLC has been used to build a fingerprint of each dye plant profile and thus used to compare to the profiles of back extraction from textiles for natural dye identification in historical artefacts. The use of solid phase extraction is compared to extraction methods with no purification step which is favourable for anthraquinone dyes but results in a major loss of glycosidic compounds when using yellow dyestuffs. Supported by 1H and 13C NMR data, the conclusive X-ray crystal structure of the natural dye ruberythric acid is presented which has never been achieved prior to this research. In a collaboration with food science two of the main components of chamomile are fully characterised by 1D and 2D, 1H and 13C NMR. These compounds are usually referred to as ferulic acid derivatives in the literature but their actual structure is reported herein. The thesis also discusses the relative dye uptake of anthraquinone compounds onto wool textiles which were measured by HPLC. Sorption isotherms for the main anthraquinones in madder; ruberythric acid, pseudopurpurin and alizarin are compared for more in-depth understanding on the method of adsorption of these compounds. Herein the glycosidic compounds in madder are shown to have a higher adsorption capacity than the aglycons. Ruberythric acid is shown to follow a Tempkin isotherm with the highest degree of correlation but both alizarin and ruberythric acid show good fitting with the Freundlich isotherm also. Pseudopurpurin was shown to follow a Freundlich isotherm with the highest degree of linearity but did also show some fitting to the Langmuir isotherm. The isotherms allow data to be collected on the energy of adsorption and draw conclusions on the effect the functional groups have on the dyeing capability which is studied herein for the first time on individual anthraquinone components. iii Studies were carried out on the acid-sensitive colorants present in madder which are degraded in the textile back extraction process. Anthraquinone aglycons alizarin and purpurin are usually identified in analysis following harsh back extraction methods, such as those using solvent mixtures with concentrated hydrochloric acid at high temperatures. Herein, a softer novel extraction method involving aqueous glucose solution was developed and compared to other back extraction techniques on wool dyed with root extract from different varieties of Rubia tinctorum. A study into the breakdown compounds of the aglycon; lucidin under acidic conditions used for traditional back extractions was also undertaken. Here it is observed that lucidin is converted into xanthopurpurin in a retro aldol like mechanism. This report discusses some of the issues raised by using these harsh back extraction methods and the problems faced in using them to analyse historic artefacts.
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Ayers, Christopher Ryan. "Effects of Mowing on Anthraquinone for Deterrence of Canada Geese and Survey of Canada Goose Fecal Contaminants." NCSU, 2009. http://www.lib.ncsu.edu/theses/available/etd-07102009-101753/.
Testo completoAbstract (sommario):
Resident Canada goose (Branta canadensis) populations have increased in urbanizing regions of the eastern United States, where man-made ponds and lakes surrounded by managed turfgrass offer ideal habitats. High concentrations of geese in these areas may cause feces accumulation, outbreaks of zoonotic diseases, eutrophication of adjacent waterways, and spread of turfgrass weeds. Although repellents effectively deter geese from turfgrass areas, frequent mowing (e.g., as in corporate parks and golf courses) may impact the efficacy of repellents. We tested the effect of 2 different mowing schedules on the longevity of FlightControl® PLUS (FCP), an anthraquinone based avian digestive irritant. From June 2007 to October 2008, we conducted 4, 30-day experiments of repellent efficacy on free-ranging geese at 8 sites. Sites were divided into 4 0.1-ha plots, each containing a unique treatment of the repellent (treated or untreated) and mowing frequency (4-day or 8-day). Each experimental session consisted of a 7-day pretreatment period of baseline observations and 30 days of post-treatment observations. Goose droppings were collected daily from transects in each plot, and percent of grass with FCP remaining was measured daily. Also, we tested 234 droppings for Giardia lamblia using a ProSpect Giardia EZ Microplate Assay, measured amounts of nitrogen (TKN) and phosphorus (TP) in 304 fecal samples, and observed 127 potted droppings for plant germination in a greenhouse. On average, goose use of FCP treated plots was lower than on untreated plots for 30 days. Over the 30 day period, goose use and FCP coverage was similar between treated plots mowed every 4 and 8 days. Further, the average FCP coverage on grass blades in treated plots decreased steadily from approximately 95% to 10%. None of the fecal samples tested positive for Giardia. The average amounts of TKN and TP in fecal samples were 24.2 mg/g (range = 12.6 â 55.7) and 3.6 mg/g (range = 1.4 â 8.3) of dry matter, respectively, with an average of 4,318.0 g/ha/day deposited by â42 geese. No controls germinated plants, whereas 4 (3.1%) fecal samples germinated plants: Pennsylvania smartweed (Polygonum pennsylvanicum L.), annual bluegrass (Poa annua L.), and 2 Kyllinga spp. FlightControl® PLUS effectively repelled Canada geese, but longevity of the chemical depends on keeping treated blades alive and under mowing height. Transmission of G. lamblia by Canada geese does not appear to be a high risk. Resident Canada goose droppings at our study sites contribute 17 â 31% of recommended N and 17 â 38% of recommended P in lawn fertilization rates. Kyllinga spp. and annual bluegrass are turfgrass weeds; however the low percentage of germinations indicates little risk of turf-feeding Canada goose weed dispersal. I recommend using FCP on areas of highest goose concentration before and when they are most prevalent. This should be done along with reduction of palatable turfgrass and annual lethal reductions. Fertilization rates should be adjusted depending on the number of geese present and the concentration of their droppings in order to save money and prevent eutrophication. Periodic testing of goose droppings for Giardia lamblia and weed seeds may prevent infestations. Research is needed to find the optimal mowing rate to keep treated blades alive and below mowing height. Information on the movements of resident Canada geese will be important for management of free-ranging populations. Identifying or developing turfgrasses that are unpalatable to Canada geese would be highly useful. If geese test positive for Giardia sp. cysts, trophozoites should be collected to identify species. The alternative to this method is to develop species specific assays. Also, research is needed on the result of resident Canada goose fecal nitrogen and phosphorus deposition on adjacent water quality.