Tesi sul tema "Selective Hydrolysis"
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Adhamy, Asghar. "Selective hydrolysis of lipids using lipases". Thesis, Teesside University, 1989. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.328090.
Testo completoHöst, Gunnar. "Engineering carbonic anhydrase for highly selective ester hydrolysis". Doctoral thesis, Linköpings universitet, Molekylär Bioteknik, 2007. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-10477.
Testo completoThe main part of this thesis describes results from protein engineering experiments, in which the catalytic activity of the enzyme human carbonic anhydrase II (HCAII) is engineered by mutagenesis. This enzyme, which catalyzes the interconversion between CO2 and HCO3- in the body, also has the ability to hydrolyze ester bonds. In one project, the specificity of HCAII towards a panel of para-nitrophenyl ester substrates, with acyl chain lengths ranging from one to five carbon atoms, was changed by enlarging the substrate binding hydrophobic pocket. A variant was identified that has highly increased specificity towards substrates with long acyl chains. The mutant V121A/V143A hydrolyzes pNPV, which has four carbon atoms in the acyl chain, with an efficiency that is increased by a factor of 3000 compared to HCAII. Further, transition state analogues (TSAs) were docked to HCAII and mutant variants, and the results were correlated to the results from kinetic measurements. This indicated that automated docking could be used to some extent to construct HCAII variants with a designed specificity. Using this approach, a HCAII mutant that can hydrolyze a model benzoate ester was created. Interestingly, the resulting variant V121A/V143A/T200A was found to be highly active with other ester substrates as well. For pNPA, a kcat/KM of 1*105 M-1s-1 was achieved, which is the highest efficiency for hydrolysis of carboxylic acid esters reported for any HCAII variant. In another project, the strong affinity between the active site zinc ion and sulfonamide was used to achieve binding of a designed substrate. Thus, the natural Zn-OH- site of HCAII was not used for catalysis, but for substrate binding. The substrate contains a benzenesulfonamide part in one end, with a para-nitrophenyl ester connected via a linker. The linker was chosen to ensure that the scissile bond is positioned close to His-64 and histidine residues introduced by mutagenesis in other positions. Using this approach, an enzyme was designed with a distinctly new two-histidine catalytic site for ester hydrolysis. The mutant, F131H/V135H, has a kcat/KM of approximately 14000 M-1s-1, which corresponds to a rate enhancement of 107 compared to a histidine mimic. Finally, results are reported on a project aimed at cloning and producing a putative carbonic anhydrase from the malaria parasite Plasmodium falciparum. The gene was cloned by PCR and the construct was overexpressed in E. coli. However, the resulting protein was not soluble, and initial attempts to refold it are also reported.
Osei-Mensah, Marian. "Synthesis of Resveratrol Ester Derivatives Using Selective Enzymatic Hydrolysis". Digital Commons @ East Tennessee State University, 2011. https://dc.etsu.edu/etd/1400.
Testo completoLombardi, Erica. "Selective photo-oxidation of cellobiose with tio2-supported metal nanoparticles". Master's thesis, Alma Mater Studiorum - Università di Bologna, 2013. http://amslaurea.unibo.it/6017/.
Testo completoFanutti, Cristina. "The selective hydrolysis of tamarind seed xyloglucan (tamarind gum) using enzymes isolated from germinated nasturtium (Tropaeolum majus L.) cotyledons". Thesis, University of Stirling, 1993. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.386556.
Testo completoDesai, S. B. "Lipases in biotransformations: resolution of some novel alcohol and diol substrates via selective hydrolysis of their esters and related mechanistic". Thesis(Ph.D.), CSIR-National Chemical Laboratory, Pune, 2000. http://dspace.ncl.res.in:8080/xmlui/handle/20.500.12252/2275.
Testo completoChapman, Jamie M. "CARBOXYL ESTER LIPASE (CEL) IS A MAJOR ENZYME RESPONSIBLE FOR THE HYDROLYSIS OF CHOLESTERYL ESTERS IN THE SELECTIVE UPTAKE PATHWAY OF THE LIVER". University of Cincinnati / OhioLINK, 2000. http://rave.ohiolink.edu/etdc/view?acc_num=ucin970245752.
Testo completoStoffregen, Stacey Anne. "Palladium(II) and platinum(II) synthetic peptidases residue- and sequence-selective hydrolysis and the photochemistry of sulfoxides, S,C-sulfonium ylides, and sulfilimines: unimolecular bond cleavage/". [Ames, Iowa : Iowa State University], 2007.
Cerca il testo completoNouveau, Thibaut. "Nébulisation de nouveaux polyplexes pour le transfert de gènes". Electronic Thesis or Diss., Sorbonne université, 2023. https://accesdistant.sorbonne-universite.fr/login?url=https://theses-intra.sorbonne-universite.fr/2023SORUS734.pdf.
Testo completoGene therapy is a form of therapy used to treat hereditary or acquired genetic diseases such as cancer or cystic fibrosis. Introducing a polynucleotide into diseased cells, either via the systmeic route or the local route (oral or nasal inhalation), corrects the defects causing the genetic mutations. However, DNA can only be internalized using a vector that protects it and enables it to reach the cell nucleus, where it will be transcribed. Various vectors (viral or synthetic) have been developed, such as PEI-based cationic polymer vectors. However, although effective, these PEI-based vectors are immunogenic at high doses. Functionalizations to reduce this toxicity, such as PEGylation, have been developed, making it possible to reinforce vectors by adding stealthiness to the final polyplexes. However, these strategies have their limitations, necessitating the synthesis of new types of polymer. POxylation represents a good alternative to PEG usage to form new polyplexes by adding a block formed from one or more poly(2-alkyl-2-oxazoline)s. The copolymers are synthesized by selective hydrolysis of a PEtOx-b-PnPrOx-b-PMeOx triblock copolymer using the thermosensitive properties of the hydrophobic blocks and a kosmotropic salt to form core-shell systems enabling hydrolysis of the PMeOx block to PEI. Then, the systems were formulated using a standard formulation and a "micro-extrusion" method. The polyplexes obtained were used in vitro experiments, by deposition or by a nebulization method, ideal for the treatment of pulmonary diseases. Very good transfection results were obtained, depending on various parameters (Mn, PEI, polymer architecture, +/- charge ratio)
Lu, Fei. "Electrochemically Induced Urea to Ammonia on Ni Based Catalyst". Ohio University / OhioLINK, 2017. http://rave.ohiolink.edu/etdc/view?acc_num=ohiou1502235953529178.
Testo completoEstrada, Anthony Armando. "I, Studies directed towards the total synthesis of nocathiacin III II, the development of a new synthetic technology for the construction of N-hydroxyindoles and synthesis of nocathiacin model systems ; III, the development of a mild and selective method for the hydrolysis of esters with trimethyltin hydroxide ; IV, contributions towards the total synthesis of thiostrepton /". Diss., Connect to a 24 p. preview or request complete full text in PDF format. Access restricted to UC campuses, 2008. http://wwwlib.umi.com/cr/ucsd/fullcit?p3321980.
Testo completoTitle from first page of PDF file (viewed September 3, 2008). Available via ProQuest Digital Dissertations. Vita. Includes bibliographical references.
Benjamin, Yuda L. "Sugarcane cultivar selection for ethanol production using dilute acid pretreatment, enzymatic hydrolysis and fermentation". Thesis, Stellenbosch : Stellenbosch University, 2014. http://hdl.handle.net/10019.1/86525.
Testo completoENGLISH ABSTRACT: The development of ―energycane‖ varieties of sugarcane for ethanol production is underway, targeting the use of both sugar juice (first generation ethanol) and bagasse (second generation ethanol). Nevertheless, identification of the preferred varieties represents the biggest challenge to the development of energycane due to large number of samples produced during breeding. In the present study, dilute acid pretreatment, enzymatic hydrolysis and fermentation processes were used to evaluate the processability of bagasse (fibrous residue generated after juice sugar extraction) from different varieties of sugarcane to select preferred varieties with the properties of improving combined ethanol yield (ethanol from juice and bagasse) per hectare. The impact of variety selection on combined ethanol yield (ethanol from juice and bagasse) per hectare was also assessed. In the first part of this study, 115 varieties of sugarcane originated from classical breeding and precision breeding (genetic engineering) were screened based on agronomic data and experimental data from biochemical processes (dilute acid pretreatment and enzymatic hydrolysis) applied to the bagasse fraction of each variety. The results showed wide variations in the chemical composition of bagasse between the varieties. Structural carbohydrates and lignin content ranged from 66.6 to 77.6% dry matter (DM) and 14.4 to 23.1% DM, respectively. The majority of precision breeding varieties showed higher arabinoxylan, lower lignin and lower ash content than most of classical breeding varieties. Combined sugar yield from the bagasse after pretreatment and enzymatic hydrolysis also varied significantly among the varieties. Up to 27.9 g/100g (dry bagasse) difference in combined sugar yield was observed. Combined sugar yield was inversely correlated with lignin as well as ash content, but it correlated positively with structural carbohydrates content. Total potential ethanol yields per hectare, calculated based on cane yield, soluble and non-soluble sugar content also differed significantly among the varieties (8,602−18,244 L/ha). Potential ethanol from bagasse contributed approximately one third of the total potential ethanol yield. Interestingly, some of the varieties had combined properties of high potential ethanol yield per hectare and improved bagasse convertibility. Thus, six varieties (3 from each breeding technology) were selected as preferred varieties for further investigation. To enhance sugar yield from bagasse, optimisation of pretreatment was conducted on the selected varieties. Industrial bagasse was included for comparison purposes. The pretreatment optimisation was based on maximising combined sugar yield from the combined pretreatment-hydrolysis process. A central composite design (CCD) was applied to investigate the effects of temperature, acid concentration and residence time on the responses and was later used to determine the maximum combined sugar yield. Pretreatment optimisation was conducted at gram scale (22.9 ml reactor) and at bench scale (1000 ml reactor). Significant differences in sugar yields (xylose, glucose, and combined sugar) between the varieties were observed. The combined sugar yields from the best performing varieties and industrial bagasse at optimal pretreatment-hydrolysis conditions differed by up to 34.1% and 33% at gram and bench scale, respectively. A high ratio of carbohydrates to lignin and low ash contents increased the release of sugar from the substrates. At mild pretreatment conditions, the differences in bioconversion efficiency between varieties were greater than at severe conditions. This observation suggests that under less severe conditions the conversion efficiency was largely determined by the properties of the biomass. Furthermore, it was demonstrated that the pretreatment conditions with temperature ranged from 184 to 200 °C and varying residence time to provide a severity factor between 3.51 and 3.96 was observed to be the area in common where 95% of maximum combined sugar yield could be obtained. Simultaneous Saccharification and Fermentation (SSF) was performed on the unwashed pressed-slurry from bagasse pretreatment at conditions for maximum combined sugar yield at bench scale. Batch and fed-batch SSF feeding strategy at different solid loadings and enzyme dosages were used aiming to reach an ethanol concentration of at least 40 g/L. The results revealed significant improvement in overall ethanol yield after SSF for the selected varieties (84.5–85.6%) compared to industrial bagasse (74.8%). The maximum ethanol concentration from the best performing varieties was 48.6−51.3 g/l and for poor performing varieties was 37.1−38.3 g/l. Ethanol concentration in the fermentation broth was inversely correlated with lignin content and the ratio of xylose to arabinose, but it showed positive correlation with glucose yield from pretreatment-enzymatic hydrolysis. The overall assessment of the varieties showed greater improvement in combined ethanol yields per hectare (71.1–90.7%) for the best performing varieties with respect to industrial sugarcane. The performance in terms of ethanol yields of selected varieties from a number harvest years was evaluated. The results showed considerable variations in ethanol yields across harvests. The results showed that the best variety in terms combined ethanol yield was not maintained across harvests. The differences in ethanol yields were greater among the varieties than across the harvests. Prolonged severe drought significantly affected the ethnol yields of all varieties represented by lower and intermediate lignin content for cane yield compared to that which had highest lignin content. However, carbohydrates content in the bagasse and sugar yield/recovery between the harvest years did not change for the most of the varieties. In summary, the present study provides evidence of the impact of cultivar selection and pretreatment optimisation in increasing conversion efficiency of bagasse. The results demonstrate that varieties with lower lignin and ash content, as well as highly substituted xylan resulted in higher sugar and ethanol yields. These results suggest that lower process requirements can be achieved without adversely affecting juice ethanol and cane yield per hectare. Nonetheless, an attempt to reduce lignin content in the bagasse, to reduce processing requirements for ethanol production, can also target the improvement of crop tolerance toward severe drought conditions.
AFRIKAANSE OPSOMMING: Die ontwikkeling van ―energie-riet‖ rasse vir etanol produksie is goed op dreef, waar beide die sap (eerste generasie etanol) en die bagasse (tweede generasie etanol) geteiken word. Die groot aantal monsters wat tydens teling geproduseer word, bied egter die grootste uitdaging vir die identifisering van nuwe rasse ten einde energie-riet te ontwikkel. In die huidige studie is verdunde suurvoorbehandeling, ensiematiese hidrolise en fermentasie-prosesse gebruik om die verwerkbaarheid van bagasse (veselagtige residu gegenereer na sap suiker ekstraksie) van verskillende suikerrietrasse te evalueer om nuwe variëteite te selekteer wat eienskappe van verbeterde gekombineerde etanolopbrengs (etanol van sap en bagasse) per hektaar toon. Die impak van variëteit-seleksie op gekombineerde etanol opbrengs (etanol van sap en bagasse) per hektaar is ook beoordeel. In die eerste deel van hierdie studie het uit ‗n siftingsproses van 115 suikerriet rasse bestaan wat deur klassieke en presisie (geneties gemodifiseerde) teling gegenereer is. Die sifting was op agronomiese data gebaseer, asook op data van verdunde suur voorafbehandeling en ensimatiese hidrolise eksperimente wat op die bagasse fraksie van elke ras uitgevoer is. Die resultate het op groot variasie in die chemiese samestelling van die bagasse van verskillende rasse gedui. Die strukturele koolhidrate het tussen 66.6 en 77.6% droë massa (DM) gewissel, terwyl die lignien inhoud ‗n variasie van 14.4 en 23.1% DM getoon het. Verder het meeste van die presisie-teling variëteite ‗n hoër arabinoxilaan, maar ‗n laer lignien en as-inhoud as meeste van die klassieke teling rasse gehad. Die gekombineerde suikeropbrengs (GSO) van die bagasse na voorafbehandeling en ensimatiese hidrolise het ook beduidend tussen rasse gewissel, waar ‗n verskil van tot 27.9 g/100g (droë bagasse) waargeneem is. Daar was ‗n omgekeerde korrelasie tussen die gekombineerde suikeropbrengs en die lignien en as-inhoud gewees, maar die opbrengs het ‗n sterk positiewe korrelasie met die strukturele koolhidrate getoon. Die totale potensiële etanol opbrengs per hektaar wat vanaf die suikerriet se oplosbare en nie-oplosbare suikerinhoud bereken is, het ook beduidend tussen rasse verskil (8,602−18,244 L/ha), waar die potensiële etanol opbrengs van die bagasse gedeelte ongeveer een derde van die totale potensiële etanol opbrengs beslaan het. Interessante bevindinge het op sommige rasse met gekombineerde eienskappe van hoë potensiële opbrengs per hektaar asook ‗n hoë omskakelingsvermoë gedui. Derhalwe is ses variëteite (drie van elke telingstegnologie) as voorkeurvariëteite vir verdere studie gekies. Om die etanol opbrengs vanaf die bagasse te verbeter was voorafbehandeling van die voorkeurvariëteite geoptimeer, en waar industriële bagasse vir vergelykingsdoeleindes ingesluit was. Vir die optimering was dit ten doel gestel om die gekombineerde suikeropbrengs van die gekombineerde voorafbehandeling-hidrolise proses te maksimeer. ‗n Sentrale saamgestelde ontwerp (SSO) is gebruik om die effek van temperatuur, suurkonsentrasie en residensietyd op die responsveranderlikes vas te stel wat uiteindelik gebruik is om die maksimum gekombineerde suikeropbrengs te bepaal. Die optimering van die voorafbehandeling is op gram-skaal in ‗n 22.9 ml reaktor, asook op bank-skaal in ‗n 1000 ml reaktor uitgevoer. Beduidende verskille in die suikeropbrengs (xilose, glukose en gekombineerde suiker) is tussen die voorkeurrasse waargeneem. Tussen die rasse wat die beste gevaar het, asook die industriële bagasse, het die gekombineerde suikeropbrengs by optimale voorafbehandeling-hidrolise toestande onderskeidelik met tot 34.1% en 33% op gram-skaal en bank-skaal gevarieer. ‗n Hoë verhouding van koolhidrate tot lignien, asook ‗n lae as-inhoud het tot ‗n toename in die vrystelling van suiker uit die substraat gelei. By matige voorafbehandelingstoestande was die verskille in omskakelingseffektiwiteit tussen rasse groter as onder hewige toestande, wat daarop gedui het dat omskakelingseffektiwiteit grotendeels deur die eienskappe van die biomassa bepaal is. Verder is daar ook gedemonstreer dat die voorbehandelingsomstandighede met temperatuur tussen 184 en 200ºC en verandering van die residensietyd om 'n hewigheidsfaktor van tussen 3.51 en 3.96 te verskaf, 'n gemeenskaplike area gelewer het waar 95% van maksimum gekombineer suiker opbrengs (GSO) verkry kon word. Gelyktydige versuikering en fermentasie (GVF) is na voorafbehandeling op ongewaste, gepersde bagasse substraat by toestande vir die maksimum gekombineerde suikeropbrengs op bank-skaal uitgevoer. Bondel en voerbondel SSF voerstrategie by verskillende vaste ladings en ensiemdoserings is gebruik om 'n etanol konsentrasie van ten minste 40 g/L te bereik. Ná GVF was die algehele etanol opbrengs vir die voorkeurvariëteite (84.5–85.6%) beduidend beter relatief tot die industriële bagasse (74.8%). Die maksimum etanol opbrengs na SSF van die rasse met die beste prestasie was 48.6-51.3 g/L en 37.1-38.3 g/L vir rasse wat swak presteer het. Die etanol konsentrasie in die fermentasiesop was omgekeerd met lignien en die verhouding van xilose tot arabinose gekorreleer, maar was duidelik positief met die glukose opbrengs vanaf voorafbehandeling-hidrolise gekorreleer. ‗n Algemene assessering het op ‗n duidelike verbetering van die voorkeurvariëteite in terme van gekombineerde etanol opbrengs per hektaar gedui (71.1–90.7%), relatief tot die industriële suikerriet. Die prestasie in terme van etanol opbrengs van geselekteerde variëteite is oor 'n reeks oesjare ge-evalueer. Die resultate het aansienlike variasies in etanol opbrengs oor oesjare getoon. Die resultate het gewys dat die beste variëteite in terme van gekombineerde etanol opbrengs nie volhou is oor oeste nie. Die verskille in etanol opbrengste tussen variëteite was groter as die verskille oor oesjare. Verlengde ernstige droogte het die etanol opbrengs van alle variëteite met laer en intermediere lignien inhoud vir rietopbrengs aansienlik beinvloed, in vergelyking met dié wat die hoogste lignien inhoud gehad het. Die koolhidraatinhoud in die bagasse en suiker opbrengs/lewering tussen die oesjare het vir die meeste variëteite egter nie gewissel nie. Ter opsomming, die huidige studie verskaf bewyse van die impak van kultivarseleksie en voorbehandelings optimisering op die verhoging van die omskakelings-doeltreffendheid van bagasse. Die resultate wys dat variëteite met laer lignien- en asinhoud, en hoogs-gesubstitueerde xilaan hoër suiker- en etanol opbrengs gelewer het. Hierdie resultate stel voor dat verminderde voorbehandelingsvereistes bereik kan word sonder om die sap etanol en rietopbrengs per hektar te benadeel. Nieteenstaande, 'n poging om die lignien inhoud van die bagasse te verminder om die verwerkingsvereistes vir etanolproduksie te verminder, kan ook die verbetering van gewas-toleransie tov ernstige droogte-toestande teiken.
Guidetti, Giulia. "Cellulose photonics : designing functionality and optical appearance of natural materials". Thesis, University of Cambridge, 2018. https://www.repository.cam.ac.uk/handle/1810/277918.
Testo completoRulence, Alexandre. "Mise en œuvre de procédés membranaires pour la séparation sélective de la nisine à partir de surnageants de culture complexes". Electronic Thesis or Diss., Université de Lille (2022-....), 2023. https://pepite-depot.univ-lille.fr/ToutIDP/EDSMRE/2023/2023ULILR034.pdf.
Testo completoNisin, a bacteriocin produced by lactic acid bacteria (LAB) presents physicochemical properties such as a thermal resistance and an antimicrobial activity against food pathogens bacteria. Nisin is actually the only bacteriocins labelled as Generally Recognized As Safe (GRAS) by the U.S Food and Drug Administration (FDA) and is thus the only bacteriocin used as a natural preservative in the food industry, making it an interesting alternative to the use of chemical preservatives. However, its uses are hampered at industrial scale due to low yields et high cost linked to its production on commercial broth and its purification necessity the combination of low yields techniques such as salting out coupled with chromatography.In this case we investigated in this work the use of food grade by-product produces by the food industry in replacement of costly commercial broth. Several by-products composed of vegetal and fish peptones were tested for the production of nisin. Whey being the most used by-product employed for production of nisin and several bacteriocin, we tested and compared different vegetal and fish proteins hydrolyzates regarding biomass production and nisin yields obtained. Several vegetal and fish protein hydrolyzates were tested with two different strains of Lactococcus lactis in order to optimize nisin production. Results showed a greater nisin production using L.lactis UL 719 when compared to a commercial strain. Results also showed the efficacy of some vegetal and one fish by-product for the production of nisin when compared to whey medium and commercial broth MRS. During this work was also investigating alternatives for nisin purification. Electro- and pressure-driven membrane process were studied for nisin purification and especially ultrafiltration (UF) and electrodialysis for which no literature reported the use of ED for nisin purification. ED was applied to the purification of nisin from a commercial solution and from a cell-free supernatant produced with whey permeate as broth for fermentation. UF was applied to the purification of nisin from a cell-free supernatant and permit to compare UF and ED in this application. This work enables us to demonstrate nisin interaction with ion exchange membrane never reported and enable its purification with purification factor comparable to conventional method actually used. Moreover, we demonstrated the use of ED not only efficient for nisin purification but with the possibility to implement ED in an eco-circularity concept, from nisin production using by-products, to its purification with ED and the recycling of salts from saline effluent produced during nisin salting-out
ZHANG, GONG-YAO, e 張功耀. "Selective hydrolysis of disaccharide esters by enzymes". Thesis, 1990. http://ndltd.ncl.edu.tw/handle/13181229398868695480.
Testo completoZhang, Gong-Yue, e 張功耀. "Selective hydrolysis of disaccharide esters by enzymes". Thesis, 1990. http://ndltd.ncl.edu.tw/handle/38272319671548393691.
Testo completo徐慈穗. "Selective hydrolysis of methyl esters of a-sialoconjugates by porine liver esterase". Thesis, 2003. http://ndltd.ncl.edu.tw/handle/53618389730505082536.
Testo completoSalehzadeh-Asl, Reza. "Enantiomeric resolution of cyclobutanones and their photochemical ring expansion products by selective enzyme acylation and hydrolysis". 2001. http://wwwlib.umi.com/cr/yorku/fullcit?pMQ66404.
Testo completoTypescript. Includes bibliographical references (leaves 56-59). Also available on the Internet. MODE OF ACCESS via web browser by entering the following URL: http://wwwlib.umi.com/cr/yorku/fullcit?pMQ66404.
Samarajeewa, Sandani. "Poly(lactide)-containing Multifunctional Nanoparticles: Synthesis, Domain-selective Degradation and Therapeutic Applicability". Thesis, 2013. http://hdl.handle.net/1969.1/149300.
Testo completoEnemchukwu, Emeka Martin. "Fabrication and use of new solid state phosphate ion selective electrodes for monitoring phosphorylation and dephosphorylation reactions". Thesis, 2012. http://hdl.handle.net/10500/11955.
Testo completoChemistry
D.Phil (Chemistry)
Lin, Chiyung, e 林繼勇. "Part 1 : A New Selective Colorimetric and Fluorescent Chemodosimeter for HSO4- Based on Hydrolysis of Schiff BasePart 2 : Colorimetric Anion Chemosensors Based on Anthraquinone : Naked-eye Detection of Isomeric Dicarboxylate and Tricarboxylate Anions". Thesis, 2013. http://ndltd.ncl.edu.tw/handle/22029086306179768244.
Testo completo靜宜大學
應用化學系
102
Part 1 :Two new receptors have been prepared based on 4-nitrobenzo[c][1,2,5]oxadiazole (NBD), (E)-N1-(2,5-dimethoxybenzylidene)-N2-(7-nitrobenzo[c][1,2,5]oxadiazol-4-yl)benzene-1,2-diamine (15) and (E)-N1-(3-methoxybenzylidene)-N2- (7-nitrobenzo[c][1,2,5]oxadiazol-4-yl)benzene-1,2-diamine (16). Receptors 15 and 16 were obtained by simple and high-yielding condensation of an amine and aldehyde, and their fluorescent and naked eye visible color changes in the presence of anions and cations were investigated. Receptors 15 and 16 are Schiff base derivatives, which hydrolyze easily in acidic solution. In acetonitrile and water (4:1) solution, they show remarkable sensitivity and selectivity to hydrogen sulfate ions. Among them, receptor 15 shows fluorescence enhancement in the presence of hydrogen sulfate, with a detection limit of (0.24 ± 0.03) uM. We isolated the hydrolysis product and determined its structure through 1H NMR, ESI-MS, and X-ray crystallography. In addition, we confirmed the effectiveness of the receptor in applications in the natural environment. Part 2 :Three new colorimetric anion receptors 16-18 were synthesized and characterized. Among them, both 16 and 18 showed good sensitivity and selectivity for discrimination of maleate versus fumarate or malate versus tartrate by dramatic colour changes in DMSO. Thus, both 16 and 18 can be used as optical chemosensors for recognition of maleate versus fumarate or malate versus tartrate anion. Besides that, the receptor 16 has also a unique colour change for recognition of either cis-aconitate or trans-aconitate in DMSO, accordingly it can be used for detection of each isomer and discrimination of cis-aconitate from trans-aconitate anion.