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Pilot-scale study of removal of anionic surfactants with trickling filterGuo, Feng 11 1900 (has links)
Anionic surfactants are wildly used in many industrial and household applications.
Because anionic surfactants are used so widely, significant attention has focused on
the removal of these contaminants from wastewater. Among various treatment
techniques, biofiltration, such as trickling filter technologies, has been employed in
many wastewater treatment plants (WWPTs) to remove anionic surfactants. However,
current knowledge of the efficacy of trickling filter to remove anionic surfactants
from wastewaters is limited. The present study characterized the performance of a
high rate (i.e. roughing) trickling filter to remove anionic surfactants both at lab-scale
and pilot-scale. Lab-scale tests investigated the biodegradation of anionic surfactants
under controllable conditions were compared with those from previous studies by
others. Pilot-scale tests investigated the efficacy of a trickling filter at removing
anionic surfactants from a wastewater over an extended period of time. The data from
the pilot-scale tests were used to model the performance of trickling filter at removing
anionic surfactants from the wastewater, using first order and modified Velz models.
The lab-scale tests indicated that high molecular weight anionic surfactants
degrade faster than the low molecular weight surfactants. The biodegradation rates
observed in the present study were similar to those from pervious studies by others.
The pilot-scale tests indicated that roughing trickling filter could remove 11% to 29%
of anionic surfactants and 4% to 22% of COD from the wastewater. Higher molecular
weight anionic surfactants were more degradable.
The experimental data could be accurately modeled using the modified Velz
model (R² value more than 0.9). The degradation rates of modified Velz model for
total anionic surfactants, high molecular weight anionic surfactants and COD were
0.053±0.0057, 0.088±0.0048 and 0.119±0.0111 (mIs)0.5 respectively.
The pilot-scale test results indicated that a high rate (i.e., roughing) trickling filter
was not capable of effectively removing anionic surfactants in the primary effluent at
Lions Gate WWTP because a relatively large trickling filter area would be required to
achieve the required surfactant removal efficiency.
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Charged Liposaccharide Based Drug Delivery SystemsAdel Abdel Rahim Unknown Date (has links)
Abstract Many hydrophilic drugs do not easily cross biological membranes. One approach to improve intestinal absorption of hydrophilic compounds is to co-administer these drug molecules with absorption enhancers to optimize their physico-chemical properties. In this project, novel liposaccharides were used to modulate the aqueous solubility as well as increase the lipophilicity, improve the intestinal permeability and hence, oral bioavailability of hydrophilic molecules. However, the solubility of the drug/liposaccharide mixtures in aqueous system might be poor, therefore, introducing a hydrophilic component such as quaternization of amine derivatives or sodium salt of carboxylic acid is required to modulate hydrophilic/lipophilic balance and in the same time and promote surfactant and ion pairing characteristics of these derivatives. This dissertation illustrates the development of novel liposaccharide absorption enhancers to be used for oral delivery of hydrophilic drugs. This research includes chemical synthesis of new ionic liposaccharides, examination of their physico-chemical properties, and their in vitro and in vivo biological examinations. The work consists of two parts; cationic and anionic liposaccharide absorption enhancers. a) Cationic Liposaccharide Absorption Enhancers The focus of this work was on the molecular design, synthesis, and evaluation of novel cationic liposaccharide derivatives as drug delivery agents to improve the oral bioavailability of piperacillin as a model hydrophilic drug. These derivatives were designed to possess surfactant as well as ion pairing properties, and were synthesized from biocompatible and biodegradable materials such as glucose, lipoamino acids and lipophilic amino acids. Thermodynamic profiles of these derivatives as well as haemolytic activity were examined. Minimum inhibitory concentrations of piperacillin/liposaccharide conjugates were studied to investigate the effect of liposaccharides on piperacillin activity. The usefulness of these derivatives as absorption enhancers for the oral delivery of piperacillin was assessed in vitro (Caco-2 cells) and in vivo (rat oral absorption). It was concluded that these derivatives did show hemolytic activity in low concentration (suitable for enhancing activity), while they increased permeability of piperacillin through Caco-2 cells. However, these promising results obtained from in vitro assay were not confirmed in vivo. viii b) Anionic Liposaccharide Absorption Enhancers In this thesis, molecular design, synthesis, and evaluation of novel anionic liposaccharide derivatives as absorption enhancers to improve the intestinal permeability of a model hydrophilic drug such as tobramycin were carried out. These derivatives were designed to have surfactant as well as ion pairing properties, and were synthesized from biocompatible materials such as sugar, lipoamino acids and amino acids. Thermodynamic profiles of these derivatives as well as haemolytic activity were examined. Many absorption enhancers have (to some extent) cytotoxic activity, therefore, cytotoxic activity of the novel anionic liposaccharides were examined. The usefulness of these derivatives as absorption enhancers to increase the lipophilicity of tobramycin and hence, its oral bioavailability, was evaluated through carrying out partition coefficient examination. It was concluded that these derivatives did not show haemolytic and cytotoxic activities in low concentration (suitable for enhancing activity). In addition, the permeability of tobramycin into the organic phase (n-octanol) was increased when liposaccharide derivatives were used. The obtained results are promising and encouraging to continue the work to include Caco-2 cells assay (in vitro assay) and oral absorption in rats (in vivo assay) as a prospective work in the future.
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Charged Liposaccharide Based Drug Delivery SystemsAdel Abdel Rahim Unknown Date (has links)
Abstract Many hydrophilic drugs do not easily cross biological membranes. One approach to improve intestinal absorption of hydrophilic compounds is to co-administer these drug molecules with absorption enhancers to optimize their physico-chemical properties. In this project, novel liposaccharides were used to modulate the aqueous solubility as well as increase the lipophilicity, improve the intestinal permeability and hence, oral bioavailability of hydrophilic molecules. However, the solubility of the drug/liposaccharide mixtures in aqueous system might be poor, therefore, introducing a hydrophilic component such as quaternization of amine derivatives or sodium salt of carboxylic acid is required to modulate hydrophilic/lipophilic balance and in the same time and promote surfactant and ion pairing characteristics of these derivatives. This dissertation illustrates the development of novel liposaccharide absorption enhancers to be used for oral delivery of hydrophilic drugs. This research includes chemical synthesis of new ionic liposaccharides, examination of their physico-chemical properties, and their in vitro and in vivo biological examinations. The work consists of two parts; cationic and anionic liposaccharide absorption enhancers. a) Cationic Liposaccharide Absorption Enhancers The focus of this work was on the molecular design, synthesis, and evaluation of novel cationic liposaccharide derivatives as drug delivery agents to improve the oral bioavailability of piperacillin as a model hydrophilic drug. These derivatives were designed to possess surfactant as well as ion pairing properties, and were synthesized from biocompatible and biodegradable materials such as glucose, lipoamino acids and lipophilic amino acids. Thermodynamic profiles of these derivatives as well as haemolytic activity were examined. Minimum inhibitory concentrations of piperacillin/liposaccharide conjugates were studied to investigate the effect of liposaccharides on piperacillin activity. The usefulness of these derivatives as absorption enhancers for the oral delivery of piperacillin was assessed in vitro (Caco-2 cells) and in vivo (rat oral absorption). It was concluded that these derivatives did show hemolytic activity in low concentration (suitable for enhancing activity), while they increased permeability of piperacillin through Caco-2 cells. However, these promising results obtained from in vitro assay were not confirmed in vivo. viii b) Anionic Liposaccharide Absorption Enhancers In this thesis, molecular design, synthesis, and evaluation of novel anionic liposaccharide derivatives as absorption enhancers to improve the intestinal permeability of a model hydrophilic drug such as tobramycin were carried out. These derivatives were designed to have surfactant as well as ion pairing properties, and were synthesized from biocompatible materials such as sugar, lipoamino acids and amino acids. Thermodynamic profiles of these derivatives as well as haemolytic activity were examined. Many absorption enhancers have (to some extent) cytotoxic activity, therefore, cytotoxic activity of the novel anionic liposaccharides were examined. The usefulness of these derivatives as absorption enhancers to increase the lipophilicity of tobramycin and hence, its oral bioavailability, was evaluated through carrying out partition coefficient examination. It was concluded that these derivatives did not show haemolytic and cytotoxic activities in low concentration (suitable for enhancing activity). In addition, the permeability of tobramycin into the organic phase (n-octanol) was increased when liposaccharide derivatives were used. The obtained results are promising and encouraging to continue the work to include Caco-2 cells assay (in vitro assay) and oral absorption in rats (in vivo assay) as a prospective work in the future.
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Charged Liposaccharide Based Drug Delivery SystemsAdel Abdel Rahim Unknown Date (has links)
Abstract Many hydrophilic drugs do not easily cross biological membranes. One approach to improve intestinal absorption of hydrophilic compounds is to co-administer these drug molecules with absorption enhancers to optimize their physico-chemical properties. In this project, novel liposaccharides were used to modulate the aqueous solubility as well as increase the lipophilicity, improve the intestinal permeability and hence, oral bioavailability of hydrophilic molecules. However, the solubility of the drug/liposaccharide mixtures in aqueous system might be poor, therefore, introducing a hydrophilic component such as quaternization of amine derivatives or sodium salt of carboxylic acid is required to modulate hydrophilic/lipophilic balance and in the same time and promote surfactant and ion pairing characteristics of these derivatives. This dissertation illustrates the development of novel liposaccharide absorption enhancers to be used for oral delivery of hydrophilic drugs. This research includes chemical synthesis of new ionic liposaccharides, examination of their physico-chemical properties, and their in vitro and in vivo biological examinations. The work consists of two parts; cationic and anionic liposaccharide absorption enhancers. a) Cationic Liposaccharide Absorption Enhancers The focus of this work was on the molecular design, synthesis, and evaluation of novel cationic liposaccharide derivatives as drug delivery agents to improve the oral bioavailability of piperacillin as a model hydrophilic drug. These derivatives were designed to possess surfactant as well as ion pairing properties, and were synthesized from biocompatible and biodegradable materials such as glucose, lipoamino acids and lipophilic amino acids. Thermodynamic profiles of these derivatives as well as haemolytic activity were examined. Minimum inhibitory concentrations of piperacillin/liposaccharide conjugates were studied to investigate the effect of liposaccharides on piperacillin activity. The usefulness of these derivatives as absorption enhancers for the oral delivery of piperacillin was assessed in vitro (Caco-2 cells) and in vivo (rat oral absorption). It was concluded that these derivatives did show hemolytic activity in low concentration (suitable for enhancing activity), while they increased permeability of piperacillin through Caco-2 cells. However, these promising results obtained from in vitro assay were not confirmed in vivo. viii b) Anionic Liposaccharide Absorption Enhancers In this thesis, molecular design, synthesis, and evaluation of novel anionic liposaccharide derivatives as absorption enhancers to improve the intestinal permeability of a model hydrophilic drug such as tobramycin were carried out. These derivatives were designed to have surfactant as well as ion pairing properties, and were synthesized from biocompatible materials such as sugar, lipoamino acids and amino acids. Thermodynamic profiles of these derivatives as well as haemolytic activity were examined. Many absorption enhancers have (to some extent) cytotoxic activity, therefore, cytotoxic activity of the novel anionic liposaccharides were examined. The usefulness of these derivatives as absorption enhancers to increase the lipophilicity of tobramycin and hence, its oral bioavailability, was evaluated through carrying out partition coefficient examination. It was concluded that these derivatives did not show haemolytic and cytotoxic activities in low concentration (suitable for enhancing activity). In addition, the permeability of tobramycin into the organic phase (n-octanol) was increased when liposaccharide derivatives were used. The obtained results are promising and encouraging to continue the work to include Caco-2 cells assay (in vitro assay) and oral absorption in rats (in vivo assay) as a prospective work in the future.
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Charged Liposaccharide Based Drug Delivery SystemsAdel Abdel Rahim Unknown Date (has links)
Abstract Many hydrophilic drugs do not easily cross biological membranes. One approach to improve intestinal absorption of hydrophilic compounds is to co-administer these drug molecules with absorption enhancers to optimize their physico-chemical properties. In this project, novel liposaccharides were used to modulate the aqueous solubility as well as increase the lipophilicity, improve the intestinal permeability and hence, oral bioavailability of hydrophilic molecules. However, the solubility of the drug/liposaccharide mixtures in aqueous system might be poor, therefore, introducing a hydrophilic component such as quaternization of amine derivatives or sodium salt of carboxylic acid is required to modulate hydrophilic/lipophilic balance and in the same time and promote surfactant and ion pairing characteristics of these derivatives. This dissertation illustrates the development of novel liposaccharide absorption enhancers to be used for oral delivery of hydrophilic drugs. This research includes chemical synthesis of new ionic liposaccharides, examination of their physico-chemical properties, and their in vitro and in vivo biological examinations. The work consists of two parts; cationic and anionic liposaccharide absorption enhancers. a) Cationic Liposaccharide Absorption Enhancers The focus of this work was on the molecular design, synthesis, and evaluation of novel cationic liposaccharide derivatives as drug delivery agents to improve the oral bioavailability of piperacillin as a model hydrophilic drug. These derivatives were designed to possess surfactant as well as ion pairing properties, and were synthesized from biocompatible and biodegradable materials such as glucose, lipoamino acids and lipophilic amino acids. Thermodynamic profiles of these derivatives as well as haemolytic activity were examined. Minimum inhibitory concentrations of piperacillin/liposaccharide conjugates were studied to investigate the effect of liposaccharides on piperacillin activity. The usefulness of these derivatives as absorption enhancers for the oral delivery of piperacillin was assessed in vitro (Caco-2 cells) and in vivo (rat oral absorption). It was concluded that these derivatives did show hemolytic activity in low concentration (suitable for enhancing activity), while they increased permeability of piperacillin through Caco-2 cells. However, these promising results obtained from in vitro assay were not confirmed in vivo. viii b) Anionic Liposaccharide Absorption Enhancers In this thesis, molecular design, synthesis, and evaluation of novel anionic liposaccharide derivatives as absorption enhancers to improve the intestinal permeability of a model hydrophilic drug such as tobramycin were carried out. These derivatives were designed to have surfactant as well as ion pairing properties, and were synthesized from biocompatible materials such as sugar, lipoamino acids and amino acids. Thermodynamic profiles of these derivatives as well as haemolytic activity were examined. Many absorption enhancers have (to some extent) cytotoxic activity, therefore, cytotoxic activity of the novel anionic liposaccharides were examined. The usefulness of these derivatives as absorption enhancers to increase the lipophilicity of tobramycin and hence, its oral bioavailability, was evaluated through carrying out partition coefficient examination. It was concluded that these derivatives did not show haemolytic and cytotoxic activities in low concentration (suitable for enhancing activity). In addition, the permeability of tobramycin into the organic phase (n-octanol) was increased when liposaccharide derivatives were used. The obtained results are promising and encouraging to continue the work to include Caco-2 cells assay (in vitro assay) and oral absorption in rats (in vivo assay) as a prospective work in the future.
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Adsorption of anionic elements to steel slagSkagerkvist, Mio January 2018 (has links)
Steel slag is a by-product from steel production and has potential to act as a sorbent for several contaminants. Contaminated water is a global problem and cheap and simple remediation solutions are often sought. The potentials are many to use an industrial residue for water purification purposes e.g. low cost. The absorption efficiency was evaluated for two different steel slags further divided into two grain sizes, <0.9 mm and 0.9-2 mm. Laboratory experiments was conducted for three anionic elements; bromine, chromate and molybdate. Controlled parameters were; time, sorbent amount and sorbate concentration. The sorption was primarily dependent on the grain size and the smaller grain size had a higher sorption of all three tested anionic species. Unfortunately the results are partially affected by the release of the tested elements from the sorbent itself.
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Microemulsions formation, stability and their characterisationsAkhtar, Mahmood January 1996 (has links)
This thesis is concerned with aspects of the surface and colloid chemistry of various microemulsion systems stabilised by pure nonionic surfactants and alcohol as well as mixtures of nonionic and anionic surfactants. Phase equilibria and interfacial characteristics of the systems are studied with a view to their potential usefulness for enhanced oil recovery, in which salinity and temperature are important parameters. The equilibrium microemulsion phases are scanned at different temperatures and salinities and thus interfacial boundaries can be determined and optimum salinity scans can be performed accurately using a modified spectrophotometer. Several analytical techniques (e.g., high performance liquid chromatography, gas chromatography, ion-exchange chromatography, mass spectrometry, viscometry, electrical conductivity, photon correlation spectroscopy, UV-spectrophotometry, thermogravimetric analysis, transmission electron microscopy, surface and interfacial tension techniques) have been used to characterise and understand the microchemistry of the microemulsion systems. Ultra-low interfacial tensions (>0.1 µN/m) can be achieved in the microemulsion systems. Surfactant transfer between phases, and phase inversion of micro emulsions are shown to occur around the condition which produces minimum interfacial tension. Adsorption of the surfactants from aqueous and nonaqueous solutions has been investigated and the results show that the extent of adsorption can be reduced significantly in the presence of alcohols (co-solvent). The extent of adsorption increases with increasing temperature and salinity; however, it decreases with an increase in the hydrophilic head group of the surfactant. Adsorption of nonionic surfactants on quartz from the nonaqueous solution (decane) is much greater than from aqueous solution. In microemulsion applications, droplet combustion of w/o microemulsions is also studied for different surfaces (i.e. silica, oxidised Fecralloy and catalyst coated Fecralloy) in the temperature range of 313-573K. Formaldehyde and acetaldehyde are formed as intermediate combustion products. Thus the microemulsion combustion can lead to new oxygenate products. The w/o microemulsion route is used to synthesize colloidal silica of controlled particle size and morphology. The particle size can be varied by changing the molar ratio of water to TEOS using a water pH of 10.5.
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Pilot-scale study of removal of anionic surfactants with trickling filterGuo, Feng 11 1900 (has links)
Anionic surfactants are wildly used in many industrial and household applications.
Because anionic surfactants are used so widely, significant attention has focused on
the removal of these contaminants from wastewater. Among various treatment
techniques, biofiltration, such as trickling filter technologies, has been employed in
many wastewater treatment plants (WWPTs) to remove anionic surfactants. However,
current knowledge of the efficacy of trickling filter to remove anionic surfactants
from wastewaters is limited. The present study characterized the performance of a
high rate (i.e. roughing) trickling filter to remove anionic surfactants both at lab-scale
and pilot-scale. Lab-scale tests investigated the biodegradation of anionic surfactants
under controllable conditions were compared with those from previous studies by
others. Pilot-scale tests investigated the efficacy of a trickling filter at removing
anionic surfactants from a wastewater over an extended period of time. The data from
the pilot-scale tests were used to model the performance of trickling filter at removing
anionic surfactants from the wastewater, using first order and modified Velz models.
The lab-scale tests indicated that high molecular weight anionic surfactants
degrade faster than the low molecular weight surfactants. The biodegradation rates
observed in the present study were similar to those from pervious studies by others.
The pilot-scale tests indicated that roughing trickling filter could remove 11% to 29%
of anionic surfactants and 4% to 22% of COD from the wastewater. Higher molecular
weight anionic surfactants were more degradable.
The experimental data could be accurately modeled using the modified Velz
model (R² value more than 0.9). The degradation rates of modified Velz model for
total anionic surfactants, high molecular weight anionic surfactants and COD were
0.053±0.0057, 0.088±0.0048 and 0.119±0.0111 (mIs)0.5 respectively.
The pilot-scale test results indicated that a high rate (i.e., roughing) trickling filter
was not capable of effectively removing anionic surfactants in the primary effluent at
Lions Gate WWTP because a relatively large trickling filter area would be required to
achieve the required surfactant removal efficiency. / Applied Science, Faculty of / Civil Engineering, Department of / Graduate
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Design Principles for High Energy Density Cathode Materials Using Anionic Redox Activity / アニオンレドックスを利用した高容量電極材料の設計指針Zhou, Yingying 23 March 2020 (has links)
京都大学 / 0048 / 新制・課程博士 / 博士(人間・環境学) / 甲第22548号 / 人博第951号 / 新制||人||226(附属図書館) / 2019||人博||951(吉田南総合図書館) / 京都大学大学院人間・環境学研究科相関環境学専攻 / (主査)教授 内本 喜晴, 教授 田部 勢津久, 准教授 藤原 直樹 / 学位規則第4条第1項該当 / Doctor of Human and Environmental Studies / Kyoto University / DFAM
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BRANCHING AND CHAIN END EFFECTS ON SURFACE FLUCTUATIONS OF POLYSTYRENE MELT FILMSZhang, Fan, Mr. January 2018 (has links)
No description available.
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