Дисертації: "Water preparation"

1

Inam, Deniz. "Organoclay Preparation For Anionic Contaminant Removal From Water." Master's thesis, METU, 2005. http://etd.lib.metu.edu.tr/upload/12606674/index.pdf.

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Increasing concern about the pollution of environment by inorganic and organic chemicals arising from naturally occurring ecological events and industrial processes has created a need for the search of new techniques in the removal of these contaminants. One of the natural material that can be used in such processes is clay. Clay minerals have large surface areas and high cation exchange capacities which enables them to be modified by cationic surfactants. The material prepared, often called as &
#8216
organoclay&
#8217
, can be used to remove hydrophobic organic and anionic contaminants from polluted water. Among the anionic contaminants, oxyanions such as nitrate, chromate are detrimental to human life and environment even at µ
g/L- mg/L levels. Application of organoclays for their removal from polluted water appears as one of the practical and rather cheap solution. In this study, a local clay from Ankara-Kalecik (Hanç
ili Bentonite) was modified by hexadecyltrimethylammonium bromide (HDTMA-Br) to a level of twice of its cation exchange capacity. This process alters the negatively charged surface of the clay into a positively charged one, providing sites for the removal of anionic contaminants. In this study, the degree of HDTMA+ uptake by the clay within a period of eight hours is found to be 97% of the initial amount added. In desorption studies it was revealed that only about 1% of the sorbed HTDMA+ was leached in a seven days of water-organoclay interaction revealing a rather stable organoclay structure in aqeous media. Sorption experiments with nitrate, borate, and chromate solutions were performed in order to determine the anion sorption capacity of the organoclays prepared. It turns out that while untreated clay has insignificant capacity, the modified clay can remove considerable amount of nitrate and chromate ions from aqeous solutions. While the nitrate sorption was increased about eleven fold, change in chromate sorption was reached to a level of twenty fold compared to that of the untreated clay. Sorption data for nitrate and chromate are both well described by the Langmuir isotherms. No significant change was observed in case of borate-organoclay interaction. Desorption of nitrate and chromate ions from organoclay surface were also investigated. Sorption of these oxyanions were found to be almost irreversible in aqeous media. The results imply that a properly prepared organoclay can be used for the removal of oxyanions, such as nitrate and chromate from polluted water systems.

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2

Kittivoravitkul, Sasitorn. "Preparation, characterisation and in vivo evaluation of DHEA protein conjugates." Thesis, University College London (University of London), 2001. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.250667.

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3

Nyamukamba, Pardon. "Preparation of photocatalytic TiO₂ nanoparticles immobilized on carbon nanofibres for water purification." Thesis, University of Fort Hare, 2011. http://hdl.handle.net/10353/367.

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Titanium dioxide nanoparticles were prepared using the sol-gel process. The effect of temperature and precursor concentration on particle size was investigated. The optimum conditions were then used to prepare carbon and nitrogen doped titanium dioxide (TiO2) nanoparticles. Doping was done to reduce band gap of the nanoparticles in order to utilize visible light in the photocatalytic degradation of organic compounds. A significant shift of the absorption edge to a longer wavelength (lower energy) from 420 nm to 456 nm and 420 nm to 428 nm was observed for the carbon doped and nitrogen doped TiO2 respectively. In this study, the prepared TiO2 photocatalyst was immobilized on carbon nanofibres to allow isolation and reuse of catalyst. The photocatalytic activity of the catalyst was tested using methyl orange as a model pollutant and was based on the decolourization of the dye as it was degraded. The doped TiO2 exhibited higher photocatalytic activity than the undoped TiO2. The materials prepared were characterized by XRD, TEM, SEM, FT-IR, DSC and TGA while the doped TiO2 was characterized by XPS, ESR and Raman Spectroscopy.

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4

COTRIM, MARYCEL E. B. "Avaliação da qualidade da água na bacia hidrográfica do Rio Ribeira de Iguape com vistas ao abastecimento público." reponame:Repositório Institucional do IPEN, 2006. http://repositorio.ipen.br:8080/xmlui/handle/123456789/11568.

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Tese (Doutoramento)
IPEN/T
Instituto de Pesquisas Energéticas e Nucleares - IPEN-CNEN/SP

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5

Stoiljković, Aleksandar. "Preparation of water-insoluble fibers from aqueous colloidal dispersions by electrospinning /." Marburg : Görich & Weiershäuser, 2007. http://bvbr.bib-bvb.de:8991/F?func=service&doc_library=BVB01&doc_number=016452800&line_number=0001&func_code=DB_RECORDS&service_type=MEDIA.

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6

Bunn, Barbara B. "Studies on the preparation and characterization of novel water-soluble catalysts." Diss., This resource online, 1993. http://scholar.lib.vt.edu/theses/available/etd-06062008-170743/.

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7

Sethi, J. (Jatin). "Cellulose nanopapers with improved preparation time, mechanical properties, and water resistance." Doctoral thesis, Oulun yliopisto, 2018. http://urn.fi/urn:isbn:9789526221540.

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Abstracts Cellulose nanopapers are the strongest polymeric material known to us, and in the near future, they are likely to be a backbone of numerous functional materials. Cellulose nanopapers have gained much attention due to qualities such as their environmentally friendly nature, renewable raw material source and biodegradability. Additionally, they offer an industrially adaptable, water-based processing route, which is similar to current paper production. Functionally, besides being tougher than any known plastic, cellulose nanopapers remain foldable like a paper. Despite their fascinating properties, cellulose nanopapers are still far from commercialisation – mainly due to two obstacles. Firstly, it can take up to hours to prepare a nanopaper due to poor draining of cellulosic nanofibres. Secondly, cellulose nanopapers have extremely poor water and humidity resistance, as up to 90% of their stiffness is lost in the presence of water. The purpose of this dissertation is to address both obstacles and suggest an eco-friendly yet industrially relevant solution. Two approaches are employed: increasing the hydrophobicity of cellulose nanofibres with lactic acid and ultrasonication (Paper I and II), and combining cellulose nanofibres with hydrophobic materials, such as polyurethane (Paper III) and lignin-rich entities (Paper IV). By using these methods, the preparation time was improved by 75% (Paper II) and by 70% (Paper IV) respectively. All reported nanopapers were significantly more tolerant of water and moisture than the reference nanopaper. The mechanical properties were also improved in Paper I and IV. Additionally, all reported nanopapers were thermally stable. This thesis also discusses the importance of quick draining in cellulose nanofibre-reinforced paper products. The results of this study are likely to aid the commercialisation of cellulose nanopapers in practical applications and the use of cellulose nanofibres in other materials, such as reinforcing paperboards. All methods used in this thesis are water-based
Tiivistelmä Selluloosapohjaiset nanopaperit ovat lujimpia tunnettuja polymeerimateriaaleja ja lähitulevaisuudessa niiden voidaan odottaa luovan perustan useille funktionaalisille materiaaleille. Nanopaperit ovat saaneet paljon huomiota ympäristöystävällisyytensä, uusiutuvan raaka-aineensa ja biohajoavuutensa ansiosta. Lisäksi niiden valmistusprosessi on vesipohjainen ja samankaltainen kuin tavallisen paperin valmistukseen käytetty teollinen prosessi. Käyttöominaisuuksiltaan ne ovat erinomaisia, sillä vaikka niiden sitkeys on parempi kuin tunnetuilla muoveilla, ovat ne silti paperin tavoin taiteltavia. Kiehtovista ominaisuuksistaan huolimatta selluloosapohjaiset nanopaperit ovat kuitenkin vielä kaukana kaupallistamisesta ja tähän vaikuttavat pääosin kaksi tekijää. Tärkein syy on selluloosananokuitujen kuivattamisen ja näin ollen nanopaperin muodostamisen vaatima huomattavan pitkä aika. Nykyisillä menetelmillä nanopaperin valmistaminen kestää useita tunteja. Toinen syy on niiden erittäin huono veden- ja kosteudenkestävyys. Ne menettävät jopa 90 % jäykkyydestään veden vaikutuksesta, mikä rajoittaa niiden käyttöä kosteissa ja vesiroiskeille alttiissa kohteissa. Tämän väitöskirjatutkimuksen päätavoitteena on löytää ekologisesti kestävä ja teollisuudessa hyödynnettävissä oleva menetelmä molempien edellä mainittujen ongelmien ratkaisemiseksi. Työssä noudatetaan kahta eri lähestymistapaa: lisätään selluloosananokuitujen hydrofobisuutta maitohapon ja ultrasonikoinnin avulla (Artikkelit I ja II), ja yhdistetään selluloosananokuituihin hydrofobisia materiaaleja, kuten polyuretaania (PU) (Artikkeli III) ja ligniinipitoisia yhdisteitä (Artikkeli IV). Näitä menetelmiä käyttämällä valmistusaikaa saatiin lyhennettyä 75 % (Artikkeli II) ja 70 % (Artikkeli IV). Kaikki valmistetut nanopaperit olivat huomattavasti veden- ja kosteudenkestävämpiä kuin verrokkinäytteet sekä osoittivat lämpöstabiiliutta. Lisäksi mekaanisia ominaisuuksia saatiin parannettua Artikkeleissa I ja IV. Tässä työssä käsitellään myös nopean kuivattamisen tärkeyttä selluloosananokuitulujitteisten paperituotteiden valmistuksessa. Saadut tulokset todennäköisesti edistävät selluloosapohjaisten nanopaperien kaupallistamista ja selluloosananokuitujen hyödyntämistä esimerkiksi kartongin lujitemateriaalina. Kaikki työssä käytetyt menetelmät ovat vesipohjaisia

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8

Sajadi, Bami Fautemeh. "Water Scarcity in the Face of Hurricanes: Improving the Resilience of Potable Water Supplies in Selected Florida Counties." Scholar Commons, 2019. https://scholarcommons.usf.edu/etd/7923.

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Severe storms can threaten the reliability and accessibility of drinking water supplies. The state of Florida is frequently impacted by hurricanes and is often struck more than once a year. An example of this can be found in 2017 when hurricanes Harvey, Irma, and Maria caused much damage. Compromised utilities, well contamination, and shortages in bottled water and ice are just some of the problems that may threaten peoples’ drinking water. Faced with these issues, preparation and response efforts must be effective in order to promote human health. Recent events like Hurricane Irma caused shortages in potable water which suggest the need for improvements in these efforts. The purpose of this study was to review management policies (for both preparations and responses) in dealing with potable water paucity caused by Hurricane Irma. Current efforts for managing potable water supplies were researched across selected counties in Florida. The effectiveness and deficiencies of these policies were analyzed. A survey was utilized to gain an understanding of the effects of these policies from the people’s perspective. This study determined several issues with potable water management efforts in dealing with severe storms. These issues were: 1) Economic constraints preventing the obtainment of drinking water (particularly for the Hispanic ethnic group), 2) Lack of concern/care in keeping sanitary private well systems, 3) Policies to encourage locals to prepare to last three days without regular water supplies were inadequate since many people were left without water for far longer time periods, 4) Younger respondents experienced greater potable water shortages than the elderly, and 5) Many people who received emergency relief did not actually require aid. This study also identified potential improvements in both the short-term (emergency responses) and long-term (preparedness) management of drinking water in the face of hurricanes. Recommendations were made to address each of the found issues and ameliorate the management of potable water. These recommendations were: 1) To promote enforcement of anti-price gouging laws 2) Enhancing education on the importance of a sanitary well system. 3) Enhancing infrastructure and power by increasing redundancy, storage capacity, structural integrity, backup power and structural stability; and/or promote education informing locals to prepare for water shortages that last longer than three days 4) Encouraging younger residents to be more involved with their community elders 5) Relief efforts should be made more effective in reaching their targeted populations (those in true need of aid). The results of this research may be used to enhance potable water management plans to avoid suffering and loss of wellbeing in future hurricanes.

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9

Liu, Ta-Kang. "Improvement in polymeric iron chloride (PICI) preparation for coagulation processes." Diss., Georgia Institute of Technology, 1999. http://hdl.handle.net/1853/32871.

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10

Paul, Seema. "Data preparation, hydrodynamic and contaminant transport shallow-water simulations of Lake Victoria." Licentiate thesis, KTH, Vatten- och miljöteknik, 2019. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-263593.

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This study explores shallow lake numerical hydrodynamic processes that support model development and validation, extreme events and effects of water circulation in Lake Victoria. Lake Victoria is the second largest freshwater lake in the world, and the largest in East Africa. It is the major freshwater reservoir and source for domestic, agriculture, industrial, fishery, and transport. The resources support livelihoods and ecosystem services for over 40 million people. The lake is severely affected by water quality degradation by pollution. This thesis aims at improving the understanding by following recommendation of the Lake Victoria Environment Management Project, Lake Victoria Basin Commission climate change adaptation strategy and action plan 2018-2023, Lake Victoria Basin Commission operational plan 2015-2020, and Lake Victoria Basin Commission report. These reports suggested detailed lake bathymetry survey, modelling of lake flow, study of lake hydrometeorological processes by modelling and simulation, to identify extreme weather events, assess water circulation effect, and study lake pollution near the shore. A numerical hydrodynamic model was built in the COMSOL Multiphysics (CM) software for assessing lake flows and water turn-over from river inflows which carry pollution. The work included the development of systematic methods for lake bathymetry that are relevant for lake numerical and hydrodynamic modelling. The hydrometeorological driven simulation model was employed to assess lake water balance, water circulation and soluble transport. Paper 1 creates a bathymetry from several methods and from several data sources, and a vertically integrated free surface flow model was implemented in CM. The model was used to investigate outflow conditions, mean velocities driven by river inflow, outflow, precipitation and evaporation. It is shown to be exactly conservative and give water level variation in reasonable agreement with measurements. The results indicate that the shallow water model is close to linear. An outflow model, linear in water level, predicts water level reasonable agreement with measurements. The findings suggest that the model should consider wind stress driven flow to provide more accurate lake flow behavior. Paper 2 performed an assessment of the hydro-meteorological processes and extreme weather events that are responsible for changing the characteristics of lake water balance, and changing streamflow variations, and lake transportation. We compare historical data over a long time with data from the model including water balance, sources of data uncertainty, correlations, extreme rain and inflow years, and seasonal variations. Solute loading and transportation was illustrated by tracing the water from the river inflows. The results indicate that the lake rainfall has a strong seasonal variation with strong correlations between tributary inflows and precipitation, and between lake outflow and water level. The tracer transport by mean flow is very slow. Flow increases somewhat in wet periods and is faster in the shallow Kenya lake zone than in the deeper Uganda and Tanzanian lake zones, where the major inflow, from the Kagera River, appears to strongly influence transportation.
Denna studie undersöker med numerisk metodik hydrodynamiska processer i den mycket grundaVictoriasjön och hur de påverkas av extrem väderlek, inflöden, och nederbörd. Victoriasjön är denandra största sötvattensjön i världen, och den största i Afrika. Den är färskvattenförråd och källa förhushåll, jordbruk, industri, fiske och transporter. Resurserna ger livsuppehåll och ekosystemtjänsterför mer än 40 miljoner människor. Sjön är utsatt för allvarliga föroreningar som försämrarvattenkvaliteten. Detta arbete avser att förbättra förståelsen genom att följa rekommendationer somgivits ut av Lake Victoria Environment Management Project (LVEMP), och Lake Victoria BasinCommissions (LVBC) rapporter om strategi för anpassning till klimatförändringar, åtgärdsplan2018-2023 och översiktsplan 2015-2020. Rapporterna föreslår detaljerad genomgång avdjupkartor, modellering av strömning i sjön i syfte att identifiera extrema väderhändelser,undersöka vattencirkulationen, och studera föroreningarna nära stränder. En hydrodynamisknumerisk modell har byggts i simuleringspaketet COMSOL Multiphysics (CM) för uppskattning avströmning och vattenutbyte från förorenade inflöden. Arbetet innefattade utveckling av metoder förvattendjups-modeller för hydrodynamiska studier. Simuleringsmodellen drivs avhydrometeorologiska data och används för vattenmängds-balans, cirkulation ochföroreningstransport.Artikel 1 skapar vattendjupskartan från flera data-mängder med olika metoder. En vertikaltintegrerad modell med fri yta implementerades i CM. Modellen ger vertikalt medelvärdesbildadehastigheter drivna av flodinflöden, utflöde, nederbörd och avdunstning. Modellen representerarvattenbalansen exakt och ger variationer i vattennivå i rimlig överensstämmelse med mätningar.Resultaten antyder att modellen är nära linjär och tids-invariant. En utflödesmodell ansatt somlinjär i vatten-nivån kan anpassas noggrant till historiska data. Bättre realism kan uppnås omvindens pådrivande verkan inkluderas.Artikel 2 går igenom de hydro-meteorologiska processer och extrema väder-händelser som ändrarvattenbalans, strömningsmönster och transport. Vi har jämfört data över femtio år med modellens,inkluderande vattennivå, källor för osäkerhet i data, korrelationer, år med extrema regn ochinflöden, och årstidsvariationer. Resultaten tyder på att nederbörden varierar kraftigt medårstiderna, och signifikanta korrelationer ses mellan nederbörd och inflöden, och mellan utflöde ochvattennivå.Transport av lösliga föroreningar illustrerades genom spårning av vatten från de olika inflödena.Spårämnestransport med vertikalt medelvärdesbildade hastigheter är mycket långsam.Strömningen ökar något i våta årstider och är snabbare i den grunda zonen i Kenya än i de djuparedelarna i Uganda och Tanzania. Det största inflödet som kommer från Kagera tycks ha stor inverkanpå transporten.

QC 20191106

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11

Nyamukamba, Pardon. "Preparation and application of plasmon metal enhanced titanium dioxide photocatalyst for the removal of organics in water." Thesis, University of Fort Hare, 2016. http://hdl.handle.net/10353/2765.

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Advanced oxidation processes are capable of removing organic compounds that cannot be removed by conventional water treatment methods. Among the oxidation processes, photo-catalysis using titanium dioxide (TiO2) is a promising method but suffers from rapid electron-hole recombination rates and only absorbs UV light which is a small percentage (5 percent) of the total solar radiation. Therefore there is a need to reduce the recombination rates and also extend the absorption of the photo-catalyst into the visible region which constitutes 55 percent of the total solar radiation. The major aims of this study were to prepare plasmon metal decorated and doped TiO2 photo-catalysts immobilized on quartz substrates and test their photo-catalytic and antimicrobial activities. The effect of film thickness (loading) and use of different shapes of plasmon metal nanostructures was investigated. TiO2 thin films were prepared by a sputter coating technique while plasmon metal (Au & Ag)/carbon co-doped TiO2 by a simple sol gel process and plasmon metal films were prepared by the thermal evaporation technique. Different plasmon metal nanostructures (nanorods, dendrites, nanowires and spherical nanoparticles) were prepared using a wet chemical technique using sodium borohydride as the reducing agent. Nanocomposites of co-doped TiO2 photo-catalyst and plasmon elements of different proportions were also prepared. The prepared photo-catalysts were coated onto etched and MPTMS (3-Mercaptopropyl trimethoxysliane) treated quartz glass substrate which is a stable support favouring easy recovery. The prepared materials were characterized by XRD, HRTEM, TEM, HRSEM, FT-IR, SEM, PIXE and TGA while the doped TiO2 was characterized by XPS, BET, CHNS and Raman Spectroscopy. The effect of pH of solution, presence of other contaminants and salts in solution, initial concentration of the model pollutant and type of the plasmonic elements on the photocatalytic activity of TiO2 towards 4-(4-sulfophenylazo)-N,N-dimethyl aniline (methyl orange) were also investigated. The selected TiO2 photo-catalyst films were tested for antimicrobial properties. The effect of different types of plasmon elements on the antimicrobial activity of TiO2 against E. coli ATCC 3695 was evaluated under both sunlight and weak UV light. Under UV light, Ag showed the highest enhancement in photo-catalytic activity of TiO2 than Au and Cu. The photo-catalytic activity of TiO2 increased with an increase in Ag content to an optimum loading and then started to decrease with a further increase in loading. For Cu and Au, photo-activity activity increased with an increase in plasmon metal content. Under sunlight, Cu showed the highest enhancement of TiO2 photocatalytic compared to Ag and Au. The change in order of deposition showed that Au films enhanced the photo-activity better when they were deposited underneath rather than on top of TiO2 on quartz supports but Ag films performed better in enhancing photo-activity when they were deposited on top of TiO2. The use of bimetallic layers and three layer systems of different plasmon elements enhanced photo-catalytic activity better than the use of a monometallic layer. The presence of other organic contaminants and salts in solutions was found to reduce the photo-degradation of methyl orange due to preferential adsorption of other contaminants. When the pH was increased, the photocatalytic activity of TiO2 towards methyl orange was reduced. In antimicrobial studies, it was found that the plasmon elements greatly improved the antibacterial action of TiO2 against Escherichia coli ATCC 3695 in water and the best antibacterial action was observed with silver/carbon co-doped TiO2 photo-catalyst under sunlight The doped samples consisted of polydisperse nanoparticles which were found to be beneficial for photo-catalytic activity enhancement under sunlight.

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12

OTOMO, JULIANA I. "Desenvolvimento e validacao de metodologia analitica para determinacao de hormonios, considerados disruptores endocrinos, nas aguas destinadas ao abastecimento publico na regiao do Rio Paraiba do Sul, SP." reponame:Repositório Institucional do IPEN, 2010. http://repositorio.ipen.br:8080/xmlui/handle/123456789/9599.

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Dissertacao (Mestrado)
IPEN/D
Instituto de Pesquisas Energeticas e Nucleares - IPEN-CNEN/SP

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13

Fabbri, Alessandro. "Preparation and Characterization of Polymeric Beads and Membranes for Boron Removal From Water." Master's thesis, Alma Mater Studiorum - Università di Bologna, 2020. http://amslaurea.unibo.it/20671/.

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Boron is an element essential for various biological processes, nevertheless at high concentration it can cause health issues in both plants and animals, thus making boron a pollutant element. Low cost and effective polymeric adsorbents capable of removing boron in aqueous solution at neutral pH were prepared for this purpose. The adsorbent selectivity towards boron was conferred taking advantage of the interaction between boric acid and the alcoholic groups of N-methyl-D-Glucamine, which are able to form specific complexes. Two different kinds of devices were produced and tested: cross-linked chitosan hydrogel beads (CCBMG) and PVA/chitosan membranes, the latter taking advantage of scCO2-assisted phase inversion technique. The capability of the adsorbents to be regenerated and to allow recovery of boric acid from a solution emulating the concentration of boric acid in seawater were evaluated.

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14

Jaafar, Maisarah. "Trace elements in natural water : the impact on quality, food preparation and production." Thesis, University of Surrey, 2018. http://epubs.surrey.ac.uk/846339/.

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The levels of arsenic (total and species) and other trace elements in natural waters of Argentina were analysed using inductively coupled plasma mass spectrometer (ICP-MS). In addition, a method was developed for the determination of Mo in waters using graphite furnace atomic absorption spectrometry (GFAAS) with an added palladium chemical modifier. The analysis of Mo in certified reference materials and water samples using both methods confirmed no statistical difference using a paired t-test (tcal = 0.276; tcrit = 2.160, df: 14 at p<0.05). Arsenic total levels (AsT) in groundwaters followed the order; central-north La Pampa (48.82-1442.60 μg/l) > south-east La Pampa (17.66-319.39 μg/l) > southern Buenos Aires (39.6-189.4 μg/l) > Río Negro/Río Colorado (1.03-38.66 μg/l). The distribution of As species (using a field-based solid phase extraction method) were significantly different between the sampling regions. In most of the study areas the groundwater exceeded 10 μg/l AsT (World Health Organisation guideline for drinking water) and can be deemed to be not fit for human consumption since the calculated hazard quotient (HQ) >1. Apart from As, Mo and V also showed higher levels in groundwaters relating to the historical deposition of volcanic ash within the Chaco-Pampean plain of Argentina. The groundwaters from La Pampa ranged from 10 to 84 μg/l Mo. Surprisingly, one farm well south of Eduardo Castex (central-northern La Pampa) used for cattle drinking water had 1381.66 μg/l Mo. Significant positive correlations were found for As, Mo and V between groundwaters used on agricultural lands and the associated soils and pastures. The arsenic concentrations in groundwaters were found to be statistically correlated (r > 0.5) with the corresponding soils (total and exchangeable fraction) and plants (leaves and roots) at p < 0.01. Based on a sequential extraction method for soils, the uptake of arsenic from the soil exchangeable fraction by plants was found to be statistically correlated (rleaves = 0.5 and rroots = 0.7 at p < 0.01). Furthermore, the use of local groundwaters for food preparation (washing and cooking) alters the elemental composition of local foodstuffs (carrots, potatoes, onions and rice). The transfer of As, Mo, V, Mn, Fe, Cu, Zn from the water to foodstuffs was found to be dependent on the levels in the water, washing steps and the cooking process (time and method). A higher uptake of As, Mo and V by foodstuffs was observed when cooking with highly ̳contaminated‘ groundwaters, especially for rice. This may significantly increase the daily dietary intake of these elements as a function of food consumption. However, drinking water (2 l/day) is still considered the main contributor to the total daily intake of As, Mo and V for the local residents who rely upon groundwater as their source for drinking and cooking due to the lower Argentine food consumption rate (38 - 196 g/day). Similar trends were observed in West Bengal, India involving rice production and preparation (washing and cooking). Elevated levels were observed for As, Mn and Fe for all sample types (plants, soils, raw and prepared rice) in relation to the use of local groundwaters. Consumption of cooked rice (500 - 750 g/day) was observed to be the major contributor to the total daily dietary intake of As, Mn and Fe (depending on the rice variety) in the Indian study area when the local groundwater (94 μg/l AsT) was used in the preparation of rice, especially for local grown rice varieties.

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15

Barkhuizen, David Andrew. "Preparation and water-gas shift performance of zinc oxide supported dispersed gold catalysts." Master's thesis, University of Cape Town, 2007. http://hdl.handle.net/11427/22065.

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Includes bibliographical references (pages 99-107).
Two deposition-precipitation style methods of preparing zinc oxide supported dispersed gold materials for use as water-gas shift catalysts were examined, with some of the better formulated materials being tested for catalytic activity, and compared to World Gold Council Au/TiO₂ reference material and a commercial copper-based WGS catalyst (Cu/ZnO/AlO₃ - C 18-7 from Sud-Chemie). Materials Synthesis: The classical deposition-precipitation synthesis from the group of Haruta (Tsubota et al., 1995) - where the support is added to a pH adjusted solution of HAuCl₄ and the system aged at constant pH and temperature - was examined, using ZnO as the support. Gold uptake by the support was confirmed to decrease with ageing pH, tending to zero as the IEPS of ZnO (~ 9) is approached. Such behaviour is both qualitatively and quantitatively consistent with theory, which proposes that the magnitude and polarity of the charge on the support surface will determine the effective carrying capacity of that surface for an (an)ionic solution phase gold species. Decreasing post-calcination (120°C) gold crystallite size with increasing ageing pH [as reported by Haruta (1997)] was also observed (figure 11.2) - but it is not clear whether this resulted from pH dependent crystallization dynamics, from crystallite size being simply determined by the amount of deposited gold (which clearly decreases with increasing pH), or from chloride induced sintering during heat treatment (with chloride uptake by the support decreasing with increasing pH [Kung et al., 2003)). Nevertheless, gold deposition at pH 8 produced highly dispersed gold crystallites around 3.5 nm in diameter. It emerged that an inherent trade-off exists with this, the classical depositionprecipitation method, in that acidic ageing pH promotes a high degree of gold uptake by the support, but produces large gold crystallites, and vice versa. To overcome this, a modified method - where HAuCI₄ and the base (ammonium carbonate) were simultaneously added dropwise to a slurry of the support, maintaining a constant pH of 8 (Fu et al., 2003b) - was investigated. This method was attractive because it is claimed to simultaneously achieve total gold uptake and post-calcination Au crystallite size in the range 5 - 6 nm. Since it was not clear from the published description whether a constant pH was maintained across the ageing period (practiced here as MDP1 ), or if the pH was rather allowed to drift (practiced here as MDP2), both alternatives were investigated. When a constant pH was maintained across the ageing period (MDP1 ), gold uptake by the support was found to reach a maximum (of ~ 60 %) when operating at a pH of ~ 8. The degree of gold uptake was found to be independent of both gold loading and support surface area. Furthermore, the degree of gold uptake achieved using this variation was increased to unity by allowing the pH to drift during the ageing period (after being initially held constant at 8 during HAuCI₄ addition) [= MDP2], instead of being maintained at a constant value via addition of nitric acid (as is done in MDP1). In terms of the size of the gold crystallites produced, after calcination in air at 400°C, a mean diameter of 3.8 ± 1.5 nm was observed for a sample 1.9 wt % in Au, increasing slightly with increasing gold loading [to 4.6 ± 1. 7 nm by 5.1 wt %Au].

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16

Ran, Rong. "Preparation and Optimization of Novel Visible-Light-Active Photocatalysts for Waste-Water Treatment." Thesis, Université d'Ottawa / University of Ottawa, 2016. http://hdl.handle.net/10393/34152.

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Photocatalysis is a series of advanced light-induced redox reaction processes resulting in the degradation and mineralization of organic pollutants in the presence of oxygen and water. Due to their capability to destroy contaminants under mild conditions, photocatalytic processes have attracted considerable attention in the field of waste-water treatment. However, photocatalytic reactions using the traditional TiO2 photocatalyst suffer from low energy efficiencies under solar irradiation. This low efficiency in the utilization of solar energy lies in its incapability in absorbing visible lights and also the high recombination rate of photo-excited species in photocatalysts. In addition, difficulties in the separation of fluids from micro- or nano-scale catalysts in large scale systems substantially impact cost efficiency in practice. In this thesis, strategies are explored which address these issues in order to improve the feasibility of solar photocatalysis. Two branches of photocatalytic transition metal-oxide semiconductor materials are investigated, namely bismuth-based and silver-based multi-phase heterogeneous photocatalysts. This research is focused on the design of visible-light-active metal-oxide photocatalysts to increase the absorption of visible light and to decrease the rates of electron-hole recombination, resulting in a high photocatalytic efficiency in regards to the degradation of organic pollutants. BiVO4 powder, synthesized from freshly made potassium metavanadate was prepared via hydrothermal treatment, characterized and experimentally investigated for the degradation of rhodamine B under visible light irradiation. The crystal structures and the specific surface areas of the composites, based on BiVO4 single phase crystal structures, are discussed. A multi-phase silver species (Ag2O/Ag3VO4/Ag4V2O7) photocatalyst was synthesized by adjusting the molar ratio of silver to vanadium (Ag to V) via hydrothermal method. The stabilities of as-prepared silver species composites regarding crystal structural changes due to photocatalytic reactions are investigated. Multi-phase silver species composites assisted with graphene oxide (GO-Ag2O/Ag3VO4/AgVO3) were synthesized at room temperature, and exhibited high visible-light photocatalytic activities regarding the degradation of model organic pollutants. The effect of graphene oxide addition on the photoactivity and on the photocorrosion of silver species composites under VLI is explored. The synergistic roles of each individual phase incorporated into the multi-phase composites are discussed regarding the photocatalytic performance.

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17

VIVEIROS, WILLIAM. "Chironomus sancticaroli: do cultivo em laboratório ao ensaio ecotoxicológico com amostras ambientais de sedimento." reponame:Repositório Institucional do IPEN, 2012. http://repositorio.ipen.br:8080/xmlui/handle/123456789/9935.

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Made available in DSpace on 2014-10-09T12:32:59Z (GMT). No. of bitstreams: 0
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Dissertação (Mestrado)
IPEN/D
Instituto de Pesquisas Energeticas e Nucleares - IPEN-CNEN/SP

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18

Fleming, Robert LeSueur. "Effects of site preparation in interior plateau clearcuts on the soil water regime and the water relations of conifer seedlings." Thesis, University of British Columbia, 1993. http://hdl.handle.net/2429/41652.

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Site preparation effects on growing season soil water regimes were investigated on three clearcut, grass-dominated sites in the Interior Douglas-fir (IDFdk), Montane Spruce (MSxk) and Engelmann spruce-Subalpine fir (ESSFxc) Biogeoclimatic Subzones, near Kamloops, British Columbia. The response of newly planted Douglas-fir (Pseudotsuga menziesii (Mirb.) Franco) and lodgepole pine (Pinus contorta Dougl.) to these treatments was determined at the IDFdk site. Soil water regimes were measured in scalped, ripped and herbicide site preparation treatments and in an untreated control using a neutron moisture meter, a two-probe gamma-density gauge, tensiometers and thermocouple psychrometers. At the IDFdk, seedlings were spring planted in each of the treatments and control to determine whether microclimate modification by site preparation would improve seedling water relations, growth and survival during the first growing season. Root zone soil water content was most limited at the low-elevation site (IDFdk) and least limited at the high-elevation site (ESSFxc). The different site preparation treatments provided similar increases in root zone soil water content, profile water storage and drainage at each site. This resulted in substantial increases in soil water supply at the lowest two sites. Site preparation resulted in increased Douglas-fir and lodgepole pine stomatal conductance (gs), transpiration (E), leaf area, root egress, root collar basal area and dry matter production. Survival of both species was high in the control and in all site preparation treatments. Both species had similar seasonal patterns of gs and E in the control. In the site preparation treatments, lodgepole pine had greater gs, and by late summer, greater E than Douglas-fir. Although lodgepole pine had substantially higher twig xylem pressure potentials and lower soil-plant liquid flow resistances than Douglas-fir, both species appeared well adapted to survive drought. First growing season stomatal responses of both species to environmental conditions, including normalized vapor pressure deficit at seedling height (Ds/P), solar irradiance (Rs) and root zone extractable water (Φe), were similar when normalized against annual maximum conductance (gsmax ). A multiplicative model with non-linear least squares optimization (NLLS) of response functions to Rs, Ds/P and Φe provided a simple, reasonably accurate description of gs/gsmax for both species, and accounted for differences in gs between the control and ripped treatment. In most cases, the NLLS models developed for a given species and year resulted in relatively precise (R²>0.60) and unbiased estimates of gs /gsmax, and yielded estimates of mean daily stomatal conductance (Gs ) and total daily transpiration (T) within 20% of measured values, for the same species in other years.
Land and Food Systems, Faculty of
Graduate

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19

Ffolliott, Peter F. "Preparation of TMDL Plans: Estimating Concentrations of Non-Point Source Pollutants to Water Bodies." Arizona-Nevada Academy of Science, 2002. http://hdl.handle.net/10150/296573.

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20

Newton, Nichola. "Preparation and properties of granular ferric hydroxide as an adsorbent in potable water treatment." Thesis, Loughborough University, 2002. https://dspace.lboro.ac.uk/2134/7866.

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Three iron oxide materials have been studied for uptake of three anions (arsenate, phosphate and fluoride) and a cation (cadmium) from aqueous solutions. Two of the materials were produced using original procedures developed at Loughborough University. The former material was conditioned by a controlled freeze-thaw procedure to enhance granularity and the latter was air-dried at room temperature. Their capacities were compared with a commercially available material supplied by GEH Wasserchemle, Germany. Pore size distributions and specific surface area values were determined by N2 analysis at 77 K. All samples possessed a reasonable specific surface area, in the range 200-300 m2/g and were mesoporous. Samples produced at Loughborough University also contained some macropores, evidence of a more amorphous structure or lack of pH control during production. X-ray diffraction indicated that all samples had some b-FeOOH present and that the chloride content and production pH affected the material crystallinity. Crystallinity increased with increasing chloride content and a higher production pH resulted in the presence of more than one phase. Chemical characterisation was also completed on all three samples. The point of zero net proton charge and isoelectric point for each material was obtained by potentiometric batch titrations and zeta potential measurements respectively. The difference in these values increased with a higher chloride content and all samples studied possessed a positive surface at low pH and negative surface at high pH. These parameters were not greatly affected by the background electrolyte concentration, implying that the background electrolyte is not specifically adsorbed. However, arsenate and phosphate appeared to be specifically adsorbed as the isoelectric point decreased. The uptake capacities for arsenate, phosphate. fluoride and cadmium of all three samples were obtained by measuring batch isotherms at 25 degrees C. The pH range was 4-9, using various initial concentrations up to a maximum of approximately 30 uM. For all anionic species studied, the capacity decreased with increasing pH, and the reverse trend was noted for cadmium. The Langmuir model provided a good fit for the anionic isotherms and the Freundlich model for the cationic isotherms. The materials studied possessed a markedly higher capacity for fluoride than arsenate and phosphate, with an intermediate capacity for cadmium. This indicates that fluoride is attached to the surface via monodentate (single) bonds, whilst both arsenate and phosphate are primarily attached to the surface via bidentate (two) bonds. Cadmium is probably bound by both these mechanisms. The effect of competing anions on arsenic uptake capacity was determined using mini-column experiments of binary (arsenate-fluoride, arsenate-Phosphate and phosphate-fluoride) and ternary (arsenate-fluoride-phosphate) mixtures. Arsenate removal was strongly affected by the presence of phosphate, but was only slightly lower in the presence of fluoride. (Continues...).

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21

Qu, Haiou. "Surface Functionalized Water-Dispersible Magnetite Nanoparticles: Preparation, Characterization and the Studies of Their Bioapplications." ScholarWorks@UNO, 2012. http://scholarworks.uno.edu/td/1536.

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Iron oxide magnetic nanoparticle synthesis and their surface functionalization hold a crucial position in the design and fabrication of functional materials for a variety of biomedical applications. Non-uniform nanoparticles with poor crystallinity, prepared by conventional methods, have only limited value in biological areas. Large scale synthesis methods that are able to produce high quality, mono-dispersed iron oxide nanoparticles using low cost and environment friendly chemicals are highly desirable. Following synthesis, appropriate surface functionalization is necessary to direct the dispersibility of nanoparticles in aqueous solution in order to provide them with acceptable colloidal stability against the ion strength and many biomolecules that nanoparticles may encounter under physiological conditions. Poorly stabilized nanoparticles that easily aggregate and form large size agglomerates would be quickly cleared by the liver and other organs and are not suitable for clinical purposes. Additionally, many interesting functionalities such as fluorescence, targeting and anti-cancer properties can be immobilized onto the surface of iron oxide magnetic nanoparticles during the surface functionalization process so as to build multifunctional platforms for disease diagnosis and treatment. Polyol method can be an effective way to prepare magnetite nanoparticles that are suitable for biological applications. In a polyol system, selected surface functionalities were introduced to the nanoparticle surface via a hot injection technique. The morphology, uniformity, crystallinity and magnetic properties were examined to understand the effect of different ligand molecules on the final product. Their surface chemistry, colloidal properties and surface reactivity were also studied to evaluate their practicability in different applications. A high efficiency in-situ method for the preparation of magnetite nanoparticles attached to silica nanospheres was also developed in a polyol system. This approach eliminates several time-consuming processing steps that are in the conventional fabrication route and directly produces water-stable magnetite-silica hybrid materials with surface availability for subsequent modifications. In addition to polyalcohol, the potential of polyamine in the preparation of water-soluble magnetite nanoparticles with amine surface functionalities was also evaluated. And it is suggested that polyamine acts as solvent, stabilizing agent and reducing agent simultaneously during the synthesis. The characterization of polyamine coated nanoparticles, their surface functionalization, and subsequent application for bioseparation and drug delivery were reported.

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22

BRITO, CARLOS F. de. "Avaliação dos efeitos da construção do rodoanel na qualidade da água e sedimento da Represa do Parque Pedroso, Santo André, SP. Estudo geoquímico de hidrocarbonetos policíclicos aromáticos (HPAs) metais e elementos traço com vistas ao abastecimento público." reponame:Repositório Institucional do IPEN, 2014. http://repositorio.ipen.br:8080/xmlui/handle/123456789/11806.

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Submitted by Claudinei Pracidelli (cpracide@ipen.br) on 2014-11-10T12:11:25Z No. of bitstreams: 0
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Tese (Doutorado em Tecnologia Nuclear)
IPEN/T
Instituto de Pesquisas Energeticas e Nucleares - IPEN-CNEN/SP

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23

OTOMO, JULIANA I. "Contribuição antrópica na qualidade das águas da represa do Guarapiranga. Um estudo sobre interferentes endócrinos." reponame:Repositório Institucional do IPEN, 2015. http://repositorio.ipen.br:8080/xmlui/handle/123456789/23821.

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Submitted by Claudinei Pracidelli (cpracide@ipen.br) on 2015-07-23T10:37:59Z No. of bitstreams: 0
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Tese (Doutorado em Tecnologia Nuclear)
IPEN/T
Instituto de Pesquisas Energeticas e Nucleares - IPEN-CNEN/SP

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24

Bildiren, Mert. "Preparation Of Clay-polymer Nanocomposite For The Retardation Of Waste Water Infiltration In Landfill Sites." Master's thesis, METU, 2007. http://etd.lib.metu.edu.tr/upload/2/12608872/index.pdf.

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In this thesis study, the use of clay-polymer nanocomposites for their applicability in landfill sites as a product of retardation of waste water infiltration was evaluated. For this purpose, organophilic clays from HDTMA+ organic cation and nanocomposites of montmorillonite were prepared. The bentonite samples B1, B2 and B3 dominantly contain 2:1 layer montmorillonite and 1:1 interstratification of illite/smectite mixed layer as clay minerals. B1 is an unmodified yellow bentonite and B2 is a grey bentonite modified from B1, by the addition of Na2CO3 (Soda Ash). They were obtained from Hanç
ili (Kalecik-Ankara) bentonite deposit which belongs to the Hancili Formation of Early Pliocene age. B3 is a standard Wyoming (SWy-1) white bentonite and belongs to the Newcastle formation of Cretaceous age. Their cation exchange and swelling capacity values were determined and the values increase from B1, B2 to B3. In order to produce clay-polymer nanocomposites, firstly organoclays were produced in bentonite samples. Claypolymer nanocomposite production was achieved by in situ intercalative polymerization successfully with intercalation and partly exfoliation of clay minerals with polyacrylamide (PAM). The samples of sand (S1), sand+bentonite (S2) and sand+nanocomposite (S3) mixtures were prepared and their permeability was determined. As a result of these values, the permeability of samples decrease from S1, S2 to S3. The results imply that the permeability of sample decreases as the claypolymer nanocomposite content increases resulting in a retardation of water penetration throughout the sample. The product has a potential to be used as a retardant for waste water infiltration in landfill sites.

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25

Yang, Chih-Hsiang, and 楊智翔. "Hydrothermal Preparation of InVO4 Catalysts for Water Splitting." Thesis, 2014. http://ndltd.ncl.edu.tw/handle/73720776627541430500.

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碩士
國立中興大學
化學工程學系所
102
Hydrogen is one of the green energy. It is clean and contain high energy (285.8J/mol). The photocatalysis is a potential method to produce hydrogen. In this study, InVO4 was chosen as a photocatalysts to split the water into hydrogen. By controlling the preparation conditions for the synthesis InVO4 to identify the surface structures、crystalline phases and the efficiency for the water splitting. Hydrothermal method has been used to synthesize InVO4 catalysts. The control parameters of hydrothermal synthesis include In/V ratio of 2:1、1:1、1:2； hydrothermal time of 1hr、2hr、4hr、8hr； pH value of 3、5、7、9 and hydrothermal temperature of 160°C、180°C、200°C、220°C. The InVO4 catalysts were characterized by FE-SEM、TEM、XRD、BET、FT-IR、and GC for analyzed the water splitting efficiency. When the starting material of In3+ is relatively higher in concentration, the SEM images of crystalline particle size is about 100 nm, but there have In(OH)3 residues present for in XRD and FT-IR analysis. In addition, the crystalline structure of InVO4 could be incomplete when there is only 1hr hydrothermal treatment. There is a better hydrogen production of 102.7μmole/g‧cat when the hydrothermal treatment time increase to 4hr and the ratio of In:V=1:2. The pH value also affects the InVO4 catalysts preparation. In strong acid environment, there is a large amount of by-products (NH4)2V6O16 form. In alkaline environment, however, there is a large amount of residues In(OH)3. As the result, the optimum conditions to synthesis InVO4 are at the ratio of In:V=1:2, pH5 and hydrothermal temperature and treatment time are 200°C for 4hr. The cumulative concentration of hydrogen after 4hr water splitting reaction is 113.9μmole/g‧cat .

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26

WANG, NAN-KAI, and 王南凱. "Preparation And Application of Water-soluble Polymer Grafted Polyaniline." Thesis, 2019. http://ndltd.ncl.edu.tw/handle/85uj75.

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碩士
南臺科技大學
化學工程與材枓工程系
107
Poly (vinyl alcohol) (PVA) has the advantages of easy synthesis, safe and low toxicity, low cost, convenient use…etc. It is a widely used water-soluble polymer. Polyaniline (PANI) has a considerable potential for application because of its low monomer cost, easy synthesis, good stability to air and moisture, and easy regulation of its conductivity. The research plan is mainly to combine the biocompatibility of water-soluble polymer polyvinyl alcohol (PVA) with the conductive properties of polyaniline (PANI) to prepare PVA grafted polyaniline conductive copolymer (PVA-g-PANI). In order to allow the product to have self-doping function, 2-acrylamido-2-methylpropane sulfonic acid (AMPS) was graft polymerized onto the PVA molecular chain to prepare PVA-g-PAMPS by using ammonium persulfate (APS) as an initiator firstly. Then, aniline (AN) monomers were graft-polymerized onto the PVA-g-PAMPS molecular chain in a PVA-g-PAMPS aqueous solution to form the conductive PVA-g-PAMPS-g-PANI. Because AMPS has sulfonic acid group, it can be used as proton acid dopant of polyaniline. Under the appropriate synthesis reaction conditions, the final product PVA-g-PAMPS-g-PANI has self-doping ability, and its conductivity is about 1.05x10-2 S/cm , it has good hydrophilicity and can be applied to humidity sensors. It can also be made into a conductive gel to increase its application potential.

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27

Lin, Shu-Chi, and 林淑淇. "Water Soluble Curcumin Preparation Via Electrospinning and Flash Nanoprecipitation." Thesis, 2016. http://ndltd.ncl.edu.tw/handle/60658881959157887425.

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碩士
國立臺灣科技大學
化學工程系
104
Curcumin is a natural occurring phenolic substance, which has wide range of pharmacological activities, such as anti-inflammatory, antioxidant, antitumor, antibacterial and anticancer properties. However, its limited aqueous solubility restricts its bioavailability. Polyvinyl pyrrolidone (PVP) is known as a biocompatible and highly water soluble polymer. Solid dispersion of curcumin in electrospun PVP (CUR-PVP) fibrous mat was prepared to increase its solubility and dissolution rate in aqueous solution. Physical characterizations of CUR-PVP by FE-SEM, FTIR-ATR, and XRD were carried out. The average diameter of CUR-PVP fiber in the mat is about 1μm. CUR-PVP can be easily dissolved in water with significantly improve curcumin solubility from 0.39±0.05μg/mL to 491.86±31.27μg/mL. The enhanced solubility is mainly due to the stable chemical complex interaction between curcumin and PVP. CUR-PVP not only can increase DPPH free radical scavenging activity as well as antioxidant activity measured by CUPRAC assay and ferric thiocyanate method but also curcumin photochemical stability. Curcumin encapsulated in acetylated starch (Cur@AS) nanoparticles of 47-58 nm in diameter was also prepared by flash nanoprecipitation to increase the solubility of curcumin. The highest production yield of Cur@AS was 92.9% with curcumin loading capability of 8.19% and curcumin loading encapsulation efficiency of 71.0%. Cur@AS nanoparticles not only can increase curcumin solubility but also increase its antioxidant activity and photochemical stability.

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28

Liu, Chia-Lin, and 劉嘉麟. "Preparation and surface activity of water-soluble PAE-DCDA surfactants." Thesis, 2003. http://ndltd.ncl.edu.tw/handle/43538782837645714363.

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碩士
國立臺灣科技大學
高分子工程系
91
A series of surfactants have been synthesized by the reaction of Epichlorohydrin、Tetraethylenepentamine、Dicyandiamide、Adipic acid、Suberic acid、Sebacic acid、Terephthalic acid and Maleic acid. There are multi-cationic groups containing in the structure of surfactants. 1H-NMR, FTMR and element analysis have been used to confirm the structure of these compounds. There surfactants have been found to exhibit excellent surface active properties including low foaming reducing pH buffer capacity, metallic ions dispersancy capacity. Their surfactants also have been found to improve the abilities in direct dye-cotton dyeing system.

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29

李榮瑞. "Preparation and surface activity of water-soluble cationic amine resins." Thesis, 2003. http://ndltd.ncl.edu.tw/handle/02026859925990772576.

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碩士
國立臺灣科技大學
高分子工程系
91
A series of surfactants have been synthesized by the reaction of diethylenetriamine、triethylenetetramine、tetraethylenepentamine、epichloryhydrin and dicyandiamide . 　　1H-NMR、FTIR and element analysis have been used to confirm structure of these compounds. These surfactants have been found to exhibit excellent surface active properties including reducing surface tension、pH buffer capacity、wetting power. These surfactants also have been found to improve the dyeability in direct dye-cotton dyeing system.

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30

邱之凱. "Preparation and surface activity of water-soluble polyamide epichlorohydrin resins." Thesis, 2002. http://ndltd.ncl.edu.tw/handle/52994890949502602792.

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碩士
國立臺灣科技大學
纖維及高分子工程系
90
Abstract A series of surfactants have been synthesized by the reaction of adipic-acid 、diethylenetriamine、triethylenetetramine 、tetraethlyene-pentamin and epichlorohydrin. There are multi-cationic groups containing in the structure of surfactants. 1H-NMR、FTIR and element analysis have been used to confirm the structure of these compounds. These surfactants have been found to exhibit excellent surface active properties including low foaming reducing pH buffer capacity、metallic ions dispersancy capacity. These surfactants also have been found to improve the abilities in direct dye-cotton dyeing system. Key word: surfactant、surface activity

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31

Wu, Chang-Lin, and 吳昌霖. "Preparation of Metal Oxide Nanoparticles in Supercritical Water and Alcohols." Thesis, 2007. http://ndltd.ncl.edu.tw/handle/62405378208582640890.

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碩士
義守大學
生物技術與化學工程研究所碩士班
95
In this study, nano-δ-alumina is obtained by continuous supercritical water hydrothermal synthesis. The obtained nanoparticles were analyzed by SEM and XRD. In stead of alumina, flaked-boehmite is obtained if the operating temperature is below 415°C. This study also precipitated nano copper oxide on carbon nanotube in the environment of alcothermal with copper nitrite as its precursor. After incineration, porous copper oxide is obtained. The porous copper oxide was analyzed by SEM to observe the change of its structure, and analyzed by ESCA to realize its oxidation state of copper. It is concluded that alcohols with low polarity can create environment that suites for the deposition of copper oxide on the surface of CNTs, and it also has poor ability to oxide the copper. It is also found that the solvent property can be changed by pressurized the liquid alcohols with CO2. The pressurized CO2 will dissolve into the liquid alcohol to reduce its polarity and to enhance the deposition. This study has successfully extended the potential applications of continuous supercritical water hydrothermal synthesis. Also, this study has explicated the effect of solvent properties on the deposition of nanoparticle on CNTs by alcothermal sysnthsis. This will provide versatile possibilities for the future studies related to hydrothermal and alcothermal synthesis.

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32

章詩偉. "Preparation and surface activity of water-soluble polymeric phenolic surfactants." Thesis, 1989. http://ndltd.ncl.edu.tw/handle/68396069523499547047.

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33

Nguyen, Thanh-Binh, and 阮青平. "Preparation of Graphitic Carbon Nitride Supported Nanocomposites for Water Purification." Thesis, 2018. http://ndltd.ncl.edu.tw/handle/nkef26.

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Анотація:

博士
國立清華大學
生醫工程與環境科學系
106
Graphitic carbon nitride (g-C3N4) is a promising material for photocatalytic applications such as solar fuels production through CO2 reduction and water splitting, and environmental treatment through the degradation of organic pollutants. This promise reflects the advantageous photophysical properties of g-C3N4 nanostructures, notably high surface area, quantum efficiency, interfacial charge separation and transport, and ease of modification through either composite formation or the incorporation of desirable surface functionalities. For heterogeneous catalytic processes, organic compounds and metal derivatives could bind or intercalate into the matrix of g-C3N4 through the surface anchoring sites to improve the catalytic reaction rate, and thus broaden the catalytic application of g-C3N4 toward organic decomposition. The unique architecture of g-C3N4 and the outstanding catalytic performance of Au nanoparticles provide a great impetus to use g-C3N4 as a promising support to judiciously decorate Au NPs for the formation of highly active and green heterogeneous catalyst. Therefore, this thesis focuses on developing novel g-C3N4-based-nanomaterirals modifying with TiO2/ZnFe2O4, which can offer further performance enhancements in photo-electrocatalytic activity for organic pollutant removal. The 1 wt% ZnFe2O4-TiO2 nanocomposites exhibit the excellent recycling and reusable ability and can retain the stable photocatalytic activity toward Bisphenol A (BPA) photodegradation for at least 10 cycles of reaction with rate constants of 0.191 – 0.218 min-1 under visible light irradiation. The photodegradation rate of BPA by ZnFe2O4-TiO2 (which was highly dependent on the water chemistry including pH, anions, and humic acid) was 20.8−21.4 times higher than that of commercial TiO2 photocatalysts. The visible-light-driven degradation of tetracycline (TE) is enhanced remarkably by the ZnFe2O4/TiO2/g-C3N4 photocathode due to the more efficient light absorption and photogenerated charge separation. By applying photoelectrocatalytic (PEC) process, the degradation rate constant of TE is increased by 48 and 24 times as much as that of photocatalytic (PC) and electrocatalytic (EC), respectively. Results clearly demonstrate the superior visible-light-driven photoactivity of g-C3N4-based-photocatalysts toward organic pollutants degradation and can open an avenue to industrial application in the future with a wide variety of potential application in the fields of photocatalysis, water splitting and energy conversion. Moreover, a photochemical green synthesis using thermal exfoliation process is developed to fabricate Au@graphitic carbon nitride (g-C3N4) nanocomposite, highly recyclable and reusable, for the catalytic reduction of nitrophenols by NaBH4. The rate constant of 4-nitrophenol reduction over Au@g-C3N4 (2 wt%) is 26.4 times that of pure Au NP in the presence of 7 mM of NaBH4 at pH 5. Besides, I have demonstrated a simple and facile synthesis method for the fabrication of Au@meso-carbon nitride (meso-CN) nanocomposite with various Au loadings for highly recyclable reduction of nitrophenols. The integration of high surface area, regular mesopores, graphitic nature of the meso-CN support as well as highly dispersed and spatially imbedded Au NPs on the Au@meso-CN composites make them excellent as catalytic reduction of 4-nitrophenol. The kobs for 4-nitrophenol reduction over 2 wt% Au@ meso-CN nanocatalysts can be up to 3.558 min-1 in the presence of NaBH4. In both cases of using graphitic carbon nitride supported Au nanocomposites for nitrophenol reduction, The detection of H radical adducts by EPR indicates that Au NPs adsorbs BH4- ions and forms Au-H species and subsequent electron transferfrom the Au-H species to nitrophenols. Results clearly demonstrate that Au@carbon-nitride nanocomposites are promising green catalysts of great application potential for nitroaromatic reduction, which can provide a new venue for tailoring Au-based nanomaterials in elucidation of a wide variety of heterogeneous catalytic reactions in water and wastewater treatment

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34

LU, FEN-CHIN, and 呂芬津. "Discussion on Preparation of water-based nail polish by polymers." Thesis, 2019. http://ndltd.ncl.edu.tw/handle/9295hq.

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Анотація:

碩士
嘉南藥理大學
化粧品應用與管理系
107
The art of fingertip is popular all over the world, and the innovation of nail products has became safer and more convenient. The quality of nail polish is closely related to its rheological properties. Appropriate rheological properties improve the coloration of the nail polish and ease of application. In recent years, the harm of solvent in nail polish has been reported in an endless stream, which has attracted attention to the non-toxic and non-irritating water-based nail polish attract attention. Currently, the commercially available water-based nail polish mostly uses polyacrylic acid as the main film-forming agent. Polyvinylpyrrolidone (PVP) is also a film-forming agent which widely used in cosmetics, but it has not been applied to nail products. Therefore, this study uses safe raw materials, PVP and its copolymers as film-forming agents, without using organic solvents that is harmful to the human. The properties of each sample were evaluated by the rheometer to test thixotropy, strain sweep, and frequency sweep, etc. The experimental results show as following: 1. Appropriately adding PVP K30 can increase thixotropy, but alone cannot stabilize the water-based nail polish formula. 2. Increasing the amount of PVP/VA can extend the LVE range and improve the stability of the nail polish, but the threshold value has been demonstrated. Extensive adding will reduce the thixotropic and viscosity. 3. A small amount of PVP K90 can improve the final product stability and thixotropy. 4. PVP/DMAPA can evenly disperse the pigment, but there is no significant improvement in thixotropic and stability properties. 5. The formulation using PVP or PVP/VA as a film former can increase the drying speed of nail polish, whereas PVP/DMAPA will increase the film drying time. 6. PVP formula should use only in powder pigment, and the PVP/DMAPA is more suitable for water-soluble dyestuff.

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35

Chen, Jhih-Cheng, and 陳志城. "Preparation and Properties of the High Water-uptake Bacterial Cellulose." Thesis, 2010. http://ndltd.ncl.edu.tw/handle/58282456718926010822.

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Анотація:

碩士
國立臺灣科技大學
高分子系
98
The high water–uptake bacterial cellulose (BC) was prepared by grafting the BC with grafting agent such as MPEG-O-(C=O)-CH2CH2- COCl (MPEG-COCl) at the basic condition to maintain or increase the internal pore structure of the BC. The originally compact packed chain in BC was broken via grafting reaction, leading to the enhancement of the movability and the hydrophile of the modified BC─BC-g-MPEG. The BC-g-MPEG thus formed could increase water-uptake after dipping in the water. The modified BC were characterized by different techniques, namely FT-IR, SEM, X-ray, water sorption assays (equilibrium water content, EWC and water retention value, WRV ) and tensile tests.

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36

Li, Jhih Ren, and 李智仁. "Preparation and characterization of high-water-content hyaluronic acid hydrogel." Thesis, 2008. http://ndltd.ncl.edu.tw/handle/26402969698027606690.

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Анотація:

碩士
長庚大學
生化與生醫工程研究所
96
The physiological properties of hyaluronic acid (HA) makes it a promising material for a variety of application. However, in the dissolved state, pure HA is hinder by the short residence time and lack of mechanical properties. To improve the degradation rate, poor mechanical properties and clearance, chemical modifications or cross-linked to form hydrogel or matrix are required when it is designed to be applied. As reported in most of literatures, HA was chemically crosslinked with EDC or GA to produce lower water content matrix (around 60%) that resulted in loss the intrinsic high hydration character of HA. Therefore, the aim of this study is to develop a new crosslinked process which is not only maintain the high water content ability of HA, but also could enhance the biostability and mechanical property. Our results shown water content of HA hydrogel is higher than 95% and remarkably lower mass loss compared with unreacted HA by thermogravimetrec measurement. Moreover, in vitro cytotoxicity test showed that there was not any relative toxic effect of the HA hydrogel. A body weight of 200g guinea pig model was used to investigated the tissue effect and biodegradation rate of HA hydrogel. In this model, HA hydrogel crosslinked with polyethyl glycol diglycidyl ether (PEGDE) performed similar effect compared with commercial product after 6 months of implantation.

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37

YU, LEE-YA, and 尤麗雅. "Preparation and application of water soluble chitosan incorporated ceramide microcapsule." Thesis, 2006. http://ndltd.ncl.edu.tw/handle/34992394553528104754.

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Анотація:

碩士
樹德科技大學
應用設計研究所
94
This study uses water-soluble chitosan as the primary material explored, ceramide as the nuclei covering material for the micro capsules, and conducts ion cross-linking in a 0.5% concentration tripolyphosphate solution. Fourier-Transform Infrared (FTIR) testing was conducted on the material’s physical and chemical properties, as well as conduct bonding analysis on the materials. Experiment shows that with cross-linking of tripolyphosphate, glutaradehyde, and genipin, the stability of micro capsules significantly increased. Further, scanning electron microscope (SEM) was used to observe surface structural changes of the base material, which clearly revealed differences of cross-linkers and differences between surface conditions. Bacterial suppression tests confirm that micro balls of chitosan maintain their antibacterial activity. In this study, antibacterial assessment not only tests the antibacterial activity of chitosan, but also used JIS L 1902’s fiber products antibacterial and bacterial resistance as benchmarks, to conduct quantitative tests in sample antibacterial ability and bacterial resistance. In antibacterial activity testing for chitosan, it was found that chitosan has antibacterial and bacterial resistance effects toward Staphylococcus aureaus and Candida albicans. Sample testing discovered that the antibacterial activity value of samples is greater than the standard value of JIS L 1902 testing, and the antibacterial activity values are also greater than standard values; this reveals that the fixed chitosan maintains its antibacterial and bacterial resistant abilities.

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38

邱源炎. "Preparation and surface activities of water soluble phenol-naphtholic copolymer." Thesis, 1995. http://ndltd.ncl.edu.tw/handle/22779519658618160170.

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Анотація:

碩士
國立臺灣科技大學
纖維及高分子工程技術研究所
83
A series of anionic water-solube polymeric surfactants has been prepared by the reaction of phenol, P-tert-methyl henol, ptert-butly phenol, sodium 1-naphthol 5-sulfonate and Sodium monochloroacetate. 　　1H-NMR、 FT-IR and element analysis have been used to confirm the structure of there compounds. These water-solube polymeric surfactants not only have its own characteristic (eg.resistence to alkali) but also have been found to exhibit excellent surface active properties including low-foaming、pH buffer capacity、wetting power、metallic ions dispersancy and chelating capacity. These surfactants have been found ot exhibit the retardering abilities in acid dye-nylon dyeing system.

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39

CHEN, AN-ZHONG, and 陳安中. "Preparation and characterization of water-soluble and crosslinkable cellulose acrylate." Thesis, 1989. http://ndltd.ncl.edu.tw/handle/57893295596259347193.

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40

Buanz, A. B. M., Richard Telford, Ian J. Scowen, and S. Gaisford. "Rapid preparation of pharmaceutical co-crystals with thermal ink-jet printing." 2012. http://hdl.handle.net/10454/8541.

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Анотація:

Yes
Thermal ink-jet printing (TIJP) is shown to be a rapid (minutes) method with which to prepare pharmaceutical co-crystals; co-crystals were identified in all cases where the co-formers could be dissolved in water and/or water/ethanol solutions.

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41

Beydoun, Donia. "Development of a novel magnetic photocatalyst : preparation, characterisation and implication for organic degradation in aqueous systems /." 2000. http://www.library.unsw.edu.au/~thesis/adt-NUN/public/adt-NUN20041011.104359/index.html.

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42

Lin, Yie-Hsean, and 林業祥. "Preparation and Hemocompatibilty of Water-Soluble Chitosan Co-ionic Complex Beads." Thesis, 2004. http://ndltd.ncl.edu.tw/handle/10076634442976877618.

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Анотація:

碩士
國立臺灣科技大學
高分子工程系
92
Co-ionic complex beads were prepared by precipitating chitosan using tripolyphosphate (TPP) and dextran sulfate (DS). Water-soluble chitosan (WSC) of two molecular masses (99 and 181 kD) and common chitosan (CS) were employed in this study. These beads were characterized using elemental analysis (EA), optical microscopy, and scanning electron microscopy (SEM). The swelling kinetics and the distribution coefficients of three compounds were also measured. The hemocompatibility was evaluated based on the protein adsorption, platelet adsorption, activated partial thrombin time (APTT), and prothrombin time (PT). The results showed that beads made from WSC exhibited higher swelling ratio (SR) than from CS. The SR increased with the DS content and depended on the pH. Beads made from WSC also exhibited lower cytotoxicity than beads from CS. The biodegrading rate by lysozyme of WSC beads was faster than that of CS beads. In addition, WSC/TPP/DS beads exhibited less protein and platelet adsorption, and longer APTT and PT. These results indicated that the addition of DS could endow WSC and CS beads with anti-coagulating ability.

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43

Yu, Chia-Chang, and 余家漳. "Study on the Preparation and stability of water soluble Curcumin complex." Thesis, 2011. http://ndltd.ncl.edu.tw/handle/23758552209363759179.

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Анотація:

碩士
國立高雄應用科技大學
化學工程與材料工程系
99
Curcuma Longa L. is used as a kind of medicine. Curcuminoids, the main component of Curcuma, is useful to antioxidation, anti-inflammation and anti-cancer.This study firstly extracted curcuminoids from curcuma roots under alkaline conditions. And control the pH value of the solution to 5. Curcuminoids were dissolved in soybean oil from the solution. After alkaline was added, curcuminoids would dissolved in the water, and control the pH value of the solution to 5 again. Curcuminoids were examined by FTIR and HPLC. The yield of curcuminoids was 2.1%. The curcuminoids are easy to be destroyed by environmental factors. The polymer and cyclodextrin were used as a stabilizer to increase resistance of the discoloration. The water-soluble complexes were prepared with sodium carboxymethyl cellulose (CMC), hydroxyethyl cellulose (HEC), hydroxypropyl methyl cellulose (HPMC), and cyclodextrin (CD) to improve the stability and water solubility of oil-soluble curcuminoids. The polymers or cyclodextrin were dissolved in water. The solution of oil-soluble curcuminoids dissolved in ethanol was added to the aqueous polymer solution. The water-soluble paprika complexes can be obtained after ethanol was evaporated. From the color destruction of sun light, heat, and pH stability tests of the four complexes which were examined by UV/Vis and FTIR, the CMC curcuminoids complex shows a much better result than the others. The rate of color destruction for CMC curcuminoids complex was a first order kinetics in the sun light and heating conditions.

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44

吳永志. "Synthesis of water-soluble chitosan derivatives and preparation of their hydrogels." Thesis, 2002. http://ndltd.ncl.edu.tw/handle/92815223086616937574.

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45

Chen, Yueh-Fang, and 陳悅芳. "Preparation of Semiconductor Photocatalyst and its Application for Water Splitting Reaction." Thesis, 2005. http://ndltd.ncl.edu.tw/handle/37563146459866966696.

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Анотація:

碩士
國立中央大學
化學工程與材料工程研究所
93
Develop a photocatalyst system for solar energy conversion to electric energy or chemical energy is a topic of great interest for fundamental and practical importance. In this study, photocatalytic activities of InVO4, InTaO4, InNbO4, In6WO12, K4Nb6O17 catalysts for water splitting under visible light irradiation were investigated. Photocatalytic activities of NaTaO3 catalysts for water splitting were studied under UV light irradiation. The effect of different preparation parameters, such as type of cocatalyst and amount of NiO loading, doping metal and pretreatment process on the photocatalysis reaction was investigated. The photocatalysts was synthesized by solid-state reaction method using metal oxide as the starting materials. The catalysts were characterized by powder X-ray diffraction (XRD), scanning electron spectroscopy (SEM), ultraviolet-visible spectroscopy (UV-Vis) and X-ray photoelectron spectroscopy (XPS). The photocatalytic reaction was carried out in a Pyrex reactor with a 500 W halogen light as visible light source and 400 W high pressure mercury lamp as UV light source. All of the catalysts were fully crystallized. SEM results In6WO12 catalysts had the smallest particle size were ca. 1~2 μm. In addition, many pin-holes appeared on InVO4 particles, after loading NiO, CoOx and RuOx. The band gap of InVO4, InTaO4, InNbO4, In6WO12, K4NB6O17 and NaTaO3 were 1.8 eV, 2.7 eV, 2.6 eV, 2.6 eV, 3.0 eV and 3.3 eV, respectively, showing that these catalysts had ability to split water into H2 and O2. For InVO4 catalyst, NiO was the best cocatalyst for water splitting, which gave the highest activity (750 μmolh-1gcat.-1 for H2 evolution and 375 μmolh-1gcat.-1 for O2) when the loading was 0.3 wt%. The pretreatment method had a great effect on the activity of the catalyst. The NiO/InVO4 catalyst which was reduced at 500oC for 2 h and oxidized at ambient condition for 48 h gave the highest activity with a rate of 896μmolh-1gcat.-1. It demonstrated that the pretreatment process plays a key role in creating high catalytic performance for the NiO/InVO4 catalyst. For InTaO4 catalysts, we also have tested various metal oxides as the additive and NiO gave the highest activity. The yields of H2 and O2 on NiO-InTaO4 were 842 μmolh-1gcat.-1 and 420 μmolh-1gcat.-1, respectively. Similarly, NiO was found to be best catalyst on InNbO4 catalyst. However, the negative of reduction-oxidation treatment was observed on NiO/InTaO4 and NiO/InNbO4. For In6WO12 catalyst, RuO2 additive gave the highest activity. The pretreatment method had a little effect on the activity of the catalyst. The yields of H2 and O2 were 774 μmolh-1gcat.-1 and 365 μmolh-1gcat.-1, respectively. K4Nb6O17 is a very active catalyst. The yields of H2 and O2 were 839 μmolh-1g cat.-1 and 415 μmolh-1g cat.-1, respectively. Photocatalytic activities of La-NaTaO3 catalysts for water splitting were studied under UV light irradiation. The yields of H2 and O2 were 1476 μmolh-1gcat.-1 and 738 μmolh-1gcat.-1, respectively.

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46

徐珠璽. "Preparation and haraterization of the Physiochemial Properties of Water Soluble Chitosan." Thesis, 1995. http://ndltd.ncl.edu.tw/handle/65279207188971283372.

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Анотація:

碩士
國立海洋大學
水產食品科學研究所
83
The aim of this study was to investigate the feasibility of using ultrasonic and/or heat (60℃) process to obtain water soluble chitosan and the characterization of the physico-chemical properties of the obtained products. Chitin was isolated from red shrimp wastes. The yield and ash content were 25.7 and 1.5%, respectively. Chitosans of various degrees of deacetylation were produced by alkali deacetylation of chitin with 50% NaOH, under a ratio of 1:32 of chitin to alkali solution, and different temperatures (60, 100, 140℃) for 3 hours. Chitosans with degree of deacetylation (DD) 56, 74, 82% (colloid titration method), viscosity average molecular weight (Mv) of 6.70×105, 1.01×105, 4.34×104 daltons were obtained. The chitosans obtained were soluble at a pH below 3. The DD of these chitosans changed to 49, 67, 74% after dialysis to remove acid. 　　One percent of the above three chitosans in 10% acetic acid were subject to ultrasonic degradation at a ultrasonic intensity of 200W, for different reaction time (0, 1.5, 3, 6, 12 hours), and temperature (20, 40, 60℃) and with 4M urea. The DD of the resulting degraded products decreased as ultrasonic time increased at 60℃. However, the DD of resulting degraded products did not change when they were ultrasonified at 20 or 40℃. 　　Effects of ultrasonic at 60℃ for various time (0, 1.5, 3, 6, 12h), with or without 4M urea on the physico-chemical properties of resulted products were studied. The results show: (1)The recovery of degraded products decreased as ultrasonic time increased. The recovey of degraded products which had ultrasonified with 4M urea were less than that of without 4M urea. The recovery was also lower of raw material of higher DD. (2)DD of degraded products decreased with increasing time of 60℃ heating or with increasing time of 60℃ heating and ultrasonic with 4M urea, whereas DD of degraded products that were reacted without 4M urea did not change with time. The higher the DD of chitosan used the faster the decrease in DD of degraded products. Difference between 60℃ treatment and 60℃ plus ultrasonic treatment was in significant. (3) Intrinsic viscosity of degraded products decreased with increasing DD of chitosan used. The intrinsic viscosity of degraded products obtained with 4M urea were higher than that without 4M urea during degradation. The intrinsic viscosities of degraded products were lower than the chitosan used in degradation processing. The decrease in intrinsic viscosity of degraded products by 60℃ heating and ultrasonic treatment were faster than that subjected to 60℃ heating alone. (4) The maximum melting temperature of degraded products prepared from higher DD chitosans were higher than that from lower DD chitosans. The maximum melting temperature of degraded products obtained from 49% DD chtiosan did not change regardless the addition of 4M urea or not. However, the maximum metling temperature of degraded products obtained from 67 or 74% DD chitosan decreased with increasing degradation time. The decrease rate in maximum melting temperature of degraded products obtained by 60℃ heating and ultrasonic were faster than that of 60℃ heat alone. (5)The resulted degraded products with DD ranged between 47~51% were soluble in water and mostly soluble in pH 7~9 solution. 　　The above results indicated that water soluble chitosan can be prepared by homogeneous acetic acid treatment on 49% DD chitosan. Whereas for 67% or 74% DD chitosan water soluble chitosan can be prepared by 60℃ or 74% DD chitosan water soluble chitosan can be prepared by 60℃ heating or 60℃ heating plus ultrasonic treatment with 4M urea for 12 hr. The resulted water soluble chitosa have a DD of 47 to 53% and molecular weight of 45,000 to 639,000.

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47

Ka, Jyun-Han, and 柯鈞瀚. "Preparation of Highly Water-Soluble and Specifically Tumor-Targeting Fe3O4 Nanoparticles." Thesis, 2009. http://ndltd.ncl.edu.tw/handle/23572652054276926022.

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Анотація:

碩士
高雄醫學大學
醫藥暨應用化學研究所
97
In this study, we modify iron oxide with poly (acrylic acid) (PAA, MW=2K Da) in order to obtain a water-soluble iron oxide. Indeed, the superior water solubility is achieved after using PAA as a capping agent, the carboxylate groups of which partially bind to the iron nanocrystal surface and partially extend into the surrounding water. Then, superparamagnetic iron oxide nanoparticle (SPION) is chelated by PAA, which is further conjugated with folic acid (FA) using polyethylene glycol (PEG) as a spacer. The monodisperse, highly water-soluble, superparamagnetic, and biocompatible magnetite nanocrystals endow versatile biomedical applications. The cell viability of PAAIO in KB cells exhibits nontoxic. The cellular internalization of PAAIO-Rh and PAAIO-Rh-FA into KB cells is observed by flow-cytometric analysis and confocal laser scanning microscopy. The preliminary results demonstrate that PAAIO-Rh-FA have the ability to target folate receptor. In MR image, the signal of PAAIO-Rh-FA show significant decreased than the signal of PAAIO-Rh in high iron concentration.

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48

LIN, CHIEN-LIANG, and 林建良. "Preparation of Poly(vinyidene fluoride) oil/water Separation membrane by electrospinning." Thesis, 2017. http://ndltd.ncl.edu.tw/handle/9y622d.

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Анотація:

碩士
國立高雄應用科技大學
化學工程與材料工程系碩士在職專班
105
In this study, polyvinylidene difluoride and N,N- Dimethylformamide were used to form 5 wt% of the electrospinning solution, and then the electrospinning fibers- and then using N-methylpyrrolidone solution wetting on the polyester fiber to produce oil-water separation composite film. Filtration of oil-water mixture, a simple filter device to filter to achieve the effect of oil and water separation, to explore the effect of oil and water separation. The useful uses three kinds of oil and water mixture, made of Sesame oil and water mixture, the production of oil and water mixture, the preparation of glycerol and water mixture, the oil and water mixture into a simple filter funnel; in the separation after the record. In the experiment, three kinds of oil-water mixture were prepared, which were mixed solution of sesame oil and water (sesame oil /H2O), mixed solution of oil and water (oil/H2O), and mixed solution of silicone oil and water (silicone oil/H2O. The oil-water mixture was poured into a simple filtration device. To explore the effect of composite membrane separation. The surface morphology of the polyester fiber woven fabric was observed with SEM, and the thermal cracking temperature of the woven fabric was determined by TGA test. The hydrophobicity of the composite membrane was obtained from the contact angle meter. From the experimental results, it was found that the polyvinylidene fluoride composite membrane filtered out oil from three kinds of oil and water mixture, oil/H2O is 51.3%, sesame oil/H2O is 59.9%, and silicone oil/H2O is 55%, respectively. Graphene composite membrane filtered out water from three kinds of oil and water mixture,, silicone oil/H2O is 93.9 %, oil/H2O is 84.8%, and sesame oil/H2O is 27.3%, respectively. Keywords: Polyvinylidene difluoride, N, N-Dimethylformamide, N-Methylpyrrolidone, oil-water separation, filtration, composite film, Graphene composite.

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49

CHEN, MAN-HSUAN, and 陳蔓萱. "Preparation and characterization of UV-curable nanocomposite as water vapor barrier." Thesis, 2018. http://ndltd.ncl.edu.tw/handle/8etj4u.

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Анотація:

碩士
國立臺北科技大學
化學工程與生物科技系化學工程碩士班
106
In recent years, owing to science and technological advances, the demand for high-tech electronic products has been increasing. In order to maintain the performance and extend the lifetimes of electronic devices, the scientists devote time and effort to barrier materials and methods. For instance, a hermetic packaging technique is essential to organic light-emitting devices (OLEDs) since the light-emitting layer and the highly active metallic electrode inside the device are rather vulnerable to moisture and oxygen attack. Since the barrier property is a key factor for sealing resins to achieve such a purpose, a thorough study on moisture barrier was hence carried out. The ladder-structured polysilsesquioxanes resins which composed of 3-trimethoxysilylpropyl methacrylate, acrylate-based siloxane, and other alcohol-based acrylate monomers, were prepared by sol-gel condensation, followed the incorporation of diluent, nanoparticles and photo-initiator. Using a common encapsulating substrate PET to test after UV curing. The results showed that the water vapor transmission rate (WVTR) of the sealant measured by Mocon is less than 0.01 (g/m2 – day) for the initial stage. The nanocomposites have been soaked in water to test the aging process to observe the environmental durability of materials. The water vapor transmission rate increased to the range of 0.9 to 1.7 g/m2 –day after being soaked in water about 15 days. The adhesion performance of encapsulated samples (after water soaking) were measured by cross-cut test, which reached 5B. Coated 50µm adhesives with PET substrates has an optical transmittance above 88% (in the visible region 380~780 nm) and the pencil hardness is 8H. The water absorption ranged from 1.1wt% to 3.3wt%. The sealants showed 5% and 10% weight loss temperatures under nitrogen at 345~378°C and 381~405°C, respectively. And the glass transition temperatures (Tg) ranged from 214°C to 262°C. Thus, these polymers can be applied in manufacturing process attributed to their excellent thermal stability. In brief, these results suggest that the UV-curable organic-inorganic hybrid nanocomposite sealant has the advantages such as fast curing, good moisture barrier, high optical transparency, high hardness, and so on. We expect that organic-inorganic hybrid nanocomposite sealant can be applied to optoelectronic encapsulation or other industry, which can maintain the performance and extend the lifetimes of products.

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50

Fang, Shih-Jung, and 方士榮. "Preparation and the Water Removal of Biodiesel From Sludge Palm Oil." Thesis, 2009. http://ndltd.ncl.edu.tw/handle/34270720745465502203.

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Анотація:

碩士
南台科技大學
奈米科技研究所
97
In this study, the parameters to prepare the biodiesel from sludge palm oil(SPO) was studied. The SPO different from the natural palm oil (Crude Palm Oil, CPO) has the characteristics of：(1) Low price the premium is only half of the CPO；(2) mud-like at 25℃,the solid content was about 50%；(3) High fatty acid content (about 50 wt.%). SPO has high fatty acids,therefor it has to carry out the acid catalyzed esterification to convert of the fatty acids in SPO to biodiesel first, and then used the alkaline catalyzed to further transesterification the SPO.The relationship of palm oil acid valued and the content of fatty acid was calculated 0.498 in this study.；After acid catalyzed esterification with methanol, the fatty acids in SPO was completely converted to fatty acid methyl ester.The water washed method was not suitable for the reducing of the acid value；According to the experimental results,the increase of NaOH(wt%) was induced to the high content of methyl ester(i.e. the conversion was high). However, the saponification of the free fatty acid was occurred as the amount of NaOH larger than 1.2 wt.% was added which leaded to the separation of two phase more difficult. The yield of methyl ester was also directly proportional to the amounts of methanol. However, as the methanol more than 40%, the yield of methyl ester was decrease.The properties of the product can compete with these of the advanced diesel. Another part of this study was the water removal of the biodiesel by the nanoabsorbent materials of water. Three different kinds of the materials were chose to absorb the water in biodiesel: Silica gel, CaO and MgO. The best nanoabsorber is Silica-gel, then CaO, MgO；The silica gel can recycle, it is more cost effective than the tradition method which used the vacuum distillation method to removal the remain water in biodiesel.

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Дисертації з теми "Water preparation"

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