The document is a final report summarizing the results of an experiment to synthesize liposome nanoparticles using varying concentrations of cholesterol. It finds that increasing the cholesterol concentration decreased the polydispersity index of the liposome solutions, indicating a more uniform size distribution. The solution with 25% cholesterol concentration had the lowest polydispersity index of 0.19 while maintaining a particle size of 140 nm. There was no clear correlation between cholesterol concentration and average particle size.
This experiment measured the density and viscosity of fluids using different methods. Density of water was measured using a beaker, Eureka can, and density bottle, with the bottle found to be most accurate. Specific weights of glycerin and castor oil were also measured using a hydrometer. Viscosity was determined using a falling sphere viscometer with spheres of different sizes dropped in glycerin and castor oil. The viscosity of glycerin had high error likely due to low fluid level, while castor oil results were close to accepted values.
Fluid Mechanic Lab - Reynold's Number ExperimentMuhammadSRaniYah
1. The document summarizes an experiment conducted by Muhammad Sulaimon Rasul to determine different types of fluid flow (laminar, transitional, turbulent) using Reynolds apparatus.
2. The experiment measured the volume of water and time taken to fill a graduated cylinder for different flow rates. This was used to calculate Reynolds number to identify flow type.
3. All results showed Reynolds numbers less than 2000, indicating laminar flow for all trials according to the theoretical boundaries between flow types.
This document discusses an experiment on agitation and determining the relationship between speed of rotation, impeller diameter, and power requirement for baffled tanks. It also examines the relationship between power number and Reynold's number. The experiment used a baffled tank and found that power requirement increased with speed. While it could not directly compare baffled and unbaffled tanks, literature shows power numbers are higher for baffled tanks as Reynold's number increases. Greater impeller diameters also require more power.
This document describes an experiment conducted to determine the friction factor of water flowing through a pipe. The experiment measured the volumetric flow rate, velocity, temperature, and pressure drop of water flowing through a pipe. These measurements were used to calculate the Reynolds number, theoretical friction factor based on equations, and experimental friction factor. The results showed that at higher Reynolds numbers, the friction factor was lower, following trends in friction factor charts. Sources of error included inaccurate measurements of pressure drop and flow time. The experiment demonstrated how friction factor depends inversely on Reynolds number for turbulent flow in a pipe.
This experiment aimed to determine the Reynolds number (NRe) as a function of flow rate for liquid flowing through a circular pipe. NRe was calculated for 6 trials with increasing flow rates. All trials had NRe below 2100, indicating laminar flow as observed by the smooth movement of dye in the pipe. As flow rate increased, NRe also increased but remained in the laminar flow regime. The results show that flow type depends on NRe, with laminar flow occurring at low velocities (NRe < 2100).
The document discusses ActifloTM Softening technology for water treatment. It combines dynamic mixing, enhanced precipitation, flocculation, lamella settling, and sludge recirculation in a single treatment line. The key benefits are its compact design and high water treatment rates of 60-80m3/h, much faster than conventional softening methods. Pilot trials at a nuclear power plant demonstrated effective softening and turbidity removal at flow rates of 60m3/h. Further development work will aim to validate design parameters and organic matter removal capabilities.
The document provides information about pressure and its measurement. It discusses hydrostatic pressure variation in fluids at rest and defines absolute, gauge, atmospheric and vacuum pressures. It describes various types of manometers used to measure pressure, including simple manometers like piezometers, U-tube manometers and single column manometers. Differential manometers like U-tube and inverted U-tube differential manometers are also covered. Several example problems are included to illustrate calculating pressure values using different types of manometers under various conditions.
This document lists and describes various types of equipment used in a material testing lab. It includes sieves of different sizes for sieve analysis to determine particle size distribution of aggregates. It also describes a slump cone and procedure for concrete slump testing to measure workability. Other equipment described includes a balance, graduated beaker, calculator, molds, hydrometer, universal testing machine, concrete mixer, pressure gauge, tamping rod, thermometer, internal and external vibrators.
This experiment measured the density and viscosity of fluids using different methods. Density of water was measured using a beaker, Eureka can, and density bottle, with the bottle found to be most accurate. Specific weights of glycerin and castor oil were also measured using a hydrometer. Viscosity was determined using a falling sphere viscometer with spheres of different sizes dropped in glycerin and castor oil. The viscosity of glycerin had high error likely due to low fluid level, while castor oil results were close to accepted values.
Fluid Mechanic Lab - Reynold's Number ExperimentMuhammadSRaniYah
1. The document summarizes an experiment conducted by Muhammad Sulaimon Rasul to determine different types of fluid flow (laminar, transitional, turbulent) using Reynolds apparatus.
2. The experiment measured the volume of water and time taken to fill a graduated cylinder for different flow rates. This was used to calculate Reynolds number to identify flow type.
3. All results showed Reynolds numbers less than 2000, indicating laminar flow for all trials according to the theoretical boundaries between flow types.
This document discusses an experiment on agitation and determining the relationship between speed of rotation, impeller diameter, and power requirement for baffled tanks. It also examines the relationship between power number and Reynold's number. The experiment used a baffled tank and found that power requirement increased with speed. While it could not directly compare baffled and unbaffled tanks, literature shows power numbers are higher for baffled tanks as Reynold's number increases. Greater impeller diameters also require more power.
This document describes an experiment conducted to determine the friction factor of water flowing through a pipe. The experiment measured the volumetric flow rate, velocity, temperature, and pressure drop of water flowing through a pipe. These measurements were used to calculate the Reynolds number, theoretical friction factor based on equations, and experimental friction factor. The results showed that at higher Reynolds numbers, the friction factor was lower, following trends in friction factor charts. Sources of error included inaccurate measurements of pressure drop and flow time. The experiment demonstrated how friction factor depends inversely on Reynolds number for turbulent flow in a pipe.
This experiment aimed to determine the Reynolds number (NRe) as a function of flow rate for liquid flowing through a circular pipe. NRe was calculated for 6 trials with increasing flow rates. All trials had NRe below 2100, indicating laminar flow as observed by the smooth movement of dye in the pipe. As flow rate increased, NRe also increased but remained in the laminar flow regime. The results show that flow type depends on NRe, with laminar flow occurring at low velocities (NRe < 2100).
The document discusses ActifloTM Softening technology for water treatment. It combines dynamic mixing, enhanced precipitation, flocculation, lamella settling, and sludge recirculation in a single treatment line. The key benefits are its compact design and high water treatment rates of 60-80m3/h, much faster than conventional softening methods. Pilot trials at a nuclear power plant demonstrated effective softening and turbidity removal at flow rates of 60m3/h. Further development work will aim to validate design parameters and organic matter removal capabilities.
The document provides information about pressure and its measurement. It discusses hydrostatic pressure variation in fluids at rest and defines absolute, gauge, atmospheric and vacuum pressures. It describes various types of manometers used to measure pressure, including simple manometers like piezometers, U-tube manometers and single column manometers. Differential manometers like U-tube and inverted U-tube differential manometers are also covered. Several example problems are included to illustrate calculating pressure values using different types of manometers under various conditions.
This document lists and describes various types of equipment used in a material testing lab. It includes sieves of different sizes for sieve analysis to determine particle size distribution of aggregates. It also describes a slump cone and procedure for concrete slump testing to measure workability. Other equipment described includes a balance, graduated beaker, calculator, molds, hydrometer, universal testing machine, concrete mixer, pressure gauge, tamping rod, thermometer, internal and external vibrators.
The experiment examined pressure drop across a packed column as a function of air and water flow rates. Pressure drop increased with higher flow rates of both air and water. The relationship between log pressure drop and log air flow rate was plotted, showing they follow the same trend as theoretical predictions. Pressure drop rose sharply before a "flooding point" where liquid accumulated and filled the column.
This document provides an overview of dry friction, including:
- Dry friction occurs between unlubricated solid surfaces and always opposes motion or impending motion. It depends on the normal force and roughness of the surfaces.
- Static friction is less than or equal to the maximum static friction force (Fmax), which is proportional to the normal force by the static coefficient of friction (μs).
- Kinetic friction occurs once motion begins and is proportional to the normal force by the kinetic coefficient of friction (μk), which is usually less than μs.
- Friction angles (θs and θk) can be defined in terms of the coefficients based on the direction of the total reaction force.
1. The silt test was conducted to determine the amount of silt in a sand sample, which could reduce concrete strength if over 8%.
2. A 200ml sand sample was added to salt solution in a graduated cylinder. After settling for 3 hours, the silt layer was measured at 150ml and sand layer at 6ml.
3. The silt content was calculated at 4%, which is under the 8% limit and means the sand can be used for concrete projects.
This document provides instructions for performing a sieve analysis test to determine the particle size distribution of fine aggregates or sand. The key steps include: 1) preparing a representative sample, 2) arranging sieves in order of decreasing size, 3) sieving the sample and weighing the material retained on each sieve, 4) calculating the percentage retained, cumulative percentage retained, and cumulative percentage passing through each sieve. The results are used to evaluate whether the sand is well graded or poorly graded and to calculate metrics like the uniformity coefficient.
LAB REPORT HYDRAULIC EXP 1 : PROPERTIES OF FLUID.YASMINE HASLAN
1. The document describes four experiments to determine the density of water and oil using different methods: a measuring cylinder, density bottle, Eureka can, and hydrometer.
2. The densities measured ranged from 885-1000 kg/m3 for water and 857-883 kg/m3 for oil depending on the method. The density bottle was deemed the most accurate method.
3. Specific gravities were also calculated from the density measurements, with water having a specific gravity of 0.953-1.027 and oil 0.865-0.947.
The document describes a jar test experiment to determine the optimal coagulant dosage for treating turbid water. Jar tests simulate the coagulation/flocculation process in water treatment plants. In this experiment, different dosages of aluminum sulfate were added to water samples, which were then rapidly and slowly mixed to form and combine floc. Turbidity measurements after settling showed an optimal dosage between 6-8 ml of aluminum sulfate coagulant reduced turbidity the most. The jar test process and results help operators adjust treatment chemicals to changing source water quality.
Liza anna jj309 fluid mechanics (buku kerjalizaannaseri
The document is a student workbook on fluid mechanics. It contains 11 units that cover topics like fluid properties, fluid statics, fluid dynamics, energy loss in pipelines, and nozzles. Example problems are provided throughout to demonstrate concepts like pressure measurements, fluid characteristics, buoyancy, hydraulic systems, and manometers. The objectives are to explain fluid mechanics concepts, solve related problems correctly, and explain their applications in engineering.
- Surveying involves making field measurements on or near the Earth's surface to determine relative positions of points or establish points. It includes preliminary surveys to collect data, layout surveys to define proposed construction locations, and construction surveys to provide line and grade during construction.
- Control surveys establish horizontal and vertical reference points and lines that preliminary and construction surveys are referenced to. Horizontal control may be tied to grid monuments, property lines, or baselines while vertical control uses benchmark elevations from leveling surveys.
- Route surveys initially layout highways as a series of tangents joined by circular curves. Compound curves consist of two or more joining circular arcs between main tangents turning in the same direction. Reverse curves connect lines through
The Bel-Champ dryer section patented by Beloit in the 1990s aimed to reduce drying shrinkage, especially at web edges, but was unable to reduce edge shrinkage significantly. As a result, the Bel-Champ design produces a very high shrinkage gradient at web edges compared to other dryer designs. This high shrinkage gradient causes problems like cockling, curling, wrinkling and increased broke that negatively impact runnability and paper quality. Additionally, the Bel-Champ requires high web and fabric temperatures that reduce drying efficiency and paper strength properties while increasing stickies problems.
The document summarizes an urban transportation study of a city divided into six zones. It provides land use data and calculates the production and attraction of trips for each zone based on residential units and commercial floor area. It then balances the production and attraction values and computes the origin-destination trip matrix between zones. Finally, it sketches the trip interchanges between the six zones.
Bulk Density & Voids in Aggregate | Jameel AcademyJameel Academy
This report details tests conducted to determine the bulk density and voids of fine and coarse aggregates. Samples of fine and coarse aggregate were tested with and without compaction. For each test, the mass of the aggregate sample, mass of the container, and volume of the container were measured. The bulk density of each sample was then calculated using these values. The results showed that bulk density ranged from 1591.4-1919.1 kg/m3 for fine aggregate and 1746.1-1591.4 kg/m3 for coarse aggregate. Voids in the samples ranged from 26.7-31.3% for fine aggregate and 34.49-39.3% for coarse aggregate. In conclusion, the
The document contains several engineering problems related to heat transfer and thermodynamics. Problem 16 asks the student to use a numerical finite difference method to construct a temperature profile table for a 1m thick slab initially at 150°C that is suddenly exposed to 250°C fluid on one face and insulated on the other, using 4 slices and time steps up to 4000s. Problem 4.1-1 asks the student to calculate the heat loss per square meter for a temporary insulating wall with given temperatures, thickness, and material properties. Problem 5.3-6 asks the student to determine the time for a furnace wall lining initially at 100°F to reach 500°F at a depth of 0.5ft, given properties
This document outlines the Environmental Impact Assessment (EIA) procedure and Environmental Management Plan (EMP) requirements in Malaysia. It discusses that the EMP is a continuation of the EIA process and ensures project proponents commit to implementing proposed mitigation measures and approval conditions. The EMP must be submitted to the Department of Environment Malaysia at least 90 days before project implementation and approved before commencement. It is a 'living document' that should be adapted throughout the project lifetime. The document provides guidelines for an effective EMP format and implementation.
The document summarizes key concepts in fluid mechanics including:
1) Types of fluid flow such as steady, unsteady, uniform, and non-uniform flow. It also discusses the continuity, Bernoulli, and momentum equations used to solve fluid problems.
2) Applications of Bernoulli's equation such as flow over weirs, through orifices and pipes, and venturi meters. It also discusses concepts like total energy, hydraulic grade line, and more.
3) Examples are provided calculating velocity, pressure, flow rates, and more at different points in pipe systems using the governing equations.
This document is a lab manual for experiments related to building materials. It provides procedures and instructions for 9 experiments:
1. Determining the normal consistency of cement.
2. Measuring the initial and final setting time of cement.
3. Testing the compressive strength of cement samples.
4. Finding the specific gravity of fine aggregate.
5. Analyzing the grain size distribution of fine aggregate using sieves.
6. Measuring the crushing value of coarse aggregate.
7. Determining the impact value of aggregate.
8. Testing the compressive strength of concrete cubes.
9. Additional aggregate testing experiments are also described.
The
Astm designation c 136 for fine aggregatesMuhammad Ahmad
This document describes a test method for determining the particle size distribution of fine aggregates through sieve analysis. The test involves drying a sample, sieving it using a nested set of sieves, weighing the material retained on each sieve, and calculating the percentages passing and retained to obtain the gradation. The results are used to determine compliance with specifications and provide data for controlling aggregate production and mixtures. The method is not applicable to materials finer than 75 microns.
The experiment investigated the characteristics of a reverse osmosis membrane system with one, two, and three membranes. A calibration curve was generated to relate conductivity to salt concentration. For a single membrane, the water permeability was found to be 0.245 g/s-psi-m2 and the salt rejection coefficient was 0.879 on average. The salt mass transfer coefficient was 15.248 m/s. For two membranes, the second membrane had a lower rejection coefficient due to its more concentrated feed. The third membrane in a three membrane system had an even lower rejection coefficient. Overall, the rejection coefficient decreased as more membranes were added due to increasing feed concentration.
Setting Time of Hydraulic Cement By Vicat Needle | Jameel AcademyJameel Academy
This report details an experiment to determine the initial and final setting times of a hydraulic cement using the Vicat needle test method. The cement paste was prepared and tested according to ASTM standards. The initial setting time was found to be 2 hours and 45 minutes when the needle penetration was 6 mm. The final setting time was then calculated using an empirical equation to be 4 hours and 48 minutes. While only two penetration measurements were taken, the results indicate the cement would be suitable for construction uses and meet the Iraqi standard of a minimum 1 hour initial setting time.
Liposomes are spherical vesicles composed of concentric bilayer membranes made of phospholipids that can encapsulate aqueous solutions. They range in size from 20nm to several micrometers. Liposomes provide advantages for drug delivery such as increased drug efficacy, reduced toxicity, and passive tumor targeting. Common methods for preparing liposomes include physical dispersion, solvent dispersion, and detergent solubilization. Liposomes are evaluated based on properties like size, surface charge, drug encapsulation efficiency, and release kinetics. They have applications in drug delivery, antimicrobial and antiviral therapies, immunology, and cosmetics.
This study developed liposomes with varying cholesterol content for controlled pulmonary drug delivery. Liposomes were prepared with phospholipids and different ratios of cholesterol (12.5%, 25%, 50%) using lipid film hydration. Theophylline was encapsulated at different concentrations and entrapment efficiency was measured. Liposomes with higher cholesterol had higher entrapment efficiency, up to 29.4% for 50% cholesterol. In vitro drug release was tested over 24 hours, showing that higher cholesterol led to more sustained release - 50% cholesterol released only 20% of drug at 7 hours while lower cholesterol formulations released drug more quickly. In conclusion, cholesterol improves liposome stability and loading capacity while providing controlled release of an encapsulated drug.
The experiment examined pressure drop across a packed column as a function of air and water flow rates. Pressure drop increased with higher flow rates of both air and water. The relationship between log pressure drop and log air flow rate was plotted, showing they follow the same trend as theoretical predictions. Pressure drop rose sharply before a "flooding point" where liquid accumulated and filled the column.
This document provides an overview of dry friction, including:
- Dry friction occurs between unlubricated solid surfaces and always opposes motion or impending motion. It depends on the normal force and roughness of the surfaces.
- Static friction is less than or equal to the maximum static friction force (Fmax), which is proportional to the normal force by the static coefficient of friction (μs).
- Kinetic friction occurs once motion begins and is proportional to the normal force by the kinetic coefficient of friction (μk), which is usually less than μs.
- Friction angles (θs and θk) can be defined in terms of the coefficients based on the direction of the total reaction force.
1. The silt test was conducted to determine the amount of silt in a sand sample, which could reduce concrete strength if over 8%.
2. A 200ml sand sample was added to salt solution in a graduated cylinder. After settling for 3 hours, the silt layer was measured at 150ml and sand layer at 6ml.
3. The silt content was calculated at 4%, which is under the 8% limit and means the sand can be used for concrete projects.
This document provides instructions for performing a sieve analysis test to determine the particle size distribution of fine aggregates or sand. The key steps include: 1) preparing a representative sample, 2) arranging sieves in order of decreasing size, 3) sieving the sample and weighing the material retained on each sieve, 4) calculating the percentage retained, cumulative percentage retained, and cumulative percentage passing through each sieve. The results are used to evaluate whether the sand is well graded or poorly graded and to calculate metrics like the uniformity coefficient.
LAB REPORT HYDRAULIC EXP 1 : PROPERTIES OF FLUID.YASMINE HASLAN
1. The document describes four experiments to determine the density of water and oil using different methods: a measuring cylinder, density bottle, Eureka can, and hydrometer.
2. The densities measured ranged from 885-1000 kg/m3 for water and 857-883 kg/m3 for oil depending on the method. The density bottle was deemed the most accurate method.
3. Specific gravities were also calculated from the density measurements, with water having a specific gravity of 0.953-1.027 and oil 0.865-0.947.
The document describes a jar test experiment to determine the optimal coagulant dosage for treating turbid water. Jar tests simulate the coagulation/flocculation process in water treatment plants. In this experiment, different dosages of aluminum sulfate were added to water samples, which were then rapidly and slowly mixed to form and combine floc. Turbidity measurements after settling showed an optimal dosage between 6-8 ml of aluminum sulfate coagulant reduced turbidity the most. The jar test process and results help operators adjust treatment chemicals to changing source water quality.
Liza anna jj309 fluid mechanics (buku kerjalizaannaseri
The document is a student workbook on fluid mechanics. It contains 11 units that cover topics like fluid properties, fluid statics, fluid dynamics, energy loss in pipelines, and nozzles. Example problems are provided throughout to demonstrate concepts like pressure measurements, fluid characteristics, buoyancy, hydraulic systems, and manometers. The objectives are to explain fluid mechanics concepts, solve related problems correctly, and explain their applications in engineering.
- Surveying involves making field measurements on or near the Earth's surface to determine relative positions of points or establish points. It includes preliminary surveys to collect data, layout surveys to define proposed construction locations, and construction surveys to provide line and grade during construction.
- Control surveys establish horizontal and vertical reference points and lines that preliminary and construction surveys are referenced to. Horizontal control may be tied to grid monuments, property lines, or baselines while vertical control uses benchmark elevations from leveling surveys.
- Route surveys initially layout highways as a series of tangents joined by circular curves. Compound curves consist of two or more joining circular arcs between main tangents turning in the same direction. Reverse curves connect lines through
The Bel-Champ dryer section patented by Beloit in the 1990s aimed to reduce drying shrinkage, especially at web edges, but was unable to reduce edge shrinkage significantly. As a result, the Bel-Champ design produces a very high shrinkage gradient at web edges compared to other dryer designs. This high shrinkage gradient causes problems like cockling, curling, wrinkling and increased broke that negatively impact runnability and paper quality. Additionally, the Bel-Champ requires high web and fabric temperatures that reduce drying efficiency and paper strength properties while increasing stickies problems.
The document summarizes an urban transportation study of a city divided into six zones. It provides land use data and calculates the production and attraction of trips for each zone based on residential units and commercial floor area. It then balances the production and attraction values and computes the origin-destination trip matrix between zones. Finally, it sketches the trip interchanges between the six zones.
Bulk Density & Voids in Aggregate | Jameel AcademyJameel Academy
This report details tests conducted to determine the bulk density and voids of fine and coarse aggregates. Samples of fine and coarse aggregate were tested with and without compaction. For each test, the mass of the aggregate sample, mass of the container, and volume of the container were measured. The bulk density of each sample was then calculated using these values. The results showed that bulk density ranged from 1591.4-1919.1 kg/m3 for fine aggregate and 1746.1-1591.4 kg/m3 for coarse aggregate. Voids in the samples ranged from 26.7-31.3% for fine aggregate and 34.49-39.3% for coarse aggregate. In conclusion, the
The document contains several engineering problems related to heat transfer and thermodynamics. Problem 16 asks the student to use a numerical finite difference method to construct a temperature profile table for a 1m thick slab initially at 150°C that is suddenly exposed to 250°C fluid on one face and insulated on the other, using 4 slices and time steps up to 4000s. Problem 4.1-1 asks the student to calculate the heat loss per square meter for a temporary insulating wall with given temperatures, thickness, and material properties. Problem 5.3-6 asks the student to determine the time for a furnace wall lining initially at 100°F to reach 500°F at a depth of 0.5ft, given properties
This document outlines the Environmental Impact Assessment (EIA) procedure and Environmental Management Plan (EMP) requirements in Malaysia. It discusses that the EMP is a continuation of the EIA process and ensures project proponents commit to implementing proposed mitigation measures and approval conditions. The EMP must be submitted to the Department of Environment Malaysia at least 90 days before project implementation and approved before commencement. It is a 'living document' that should be adapted throughout the project lifetime. The document provides guidelines for an effective EMP format and implementation.
The document summarizes key concepts in fluid mechanics including:
1) Types of fluid flow such as steady, unsteady, uniform, and non-uniform flow. It also discusses the continuity, Bernoulli, and momentum equations used to solve fluid problems.
2) Applications of Bernoulli's equation such as flow over weirs, through orifices and pipes, and venturi meters. It also discusses concepts like total energy, hydraulic grade line, and more.
3) Examples are provided calculating velocity, pressure, flow rates, and more at different points in pipe systems using the governing equations.
This document is a lab manual for experiments related to building materials. It provides procedures and instructions for 9 experiments:
1. Determining the normal consistency of cement.
2. Measuring the initial and final setting time of cement.
3. Testing the compressive strength of cement samples.
4. Finding the specific gravity of fine aggregate.
5. Analyzing the grain size distribution of fine aggregate using sieves.
6. Measuring the crushing value of coarse aggregate.
7. Determining the impact value of aggregate.
8. Testing the compressive strength of concrete cubes.
9. Additional aggregate testing experiments are also described.
The
Astm designation c 136 for fine aggregatesMuhammad Ahmad
This document describes a test method for determining the particle size distribution of fine aggregates through sieve analysis. The test involves drying a sample, sieving it using a nested set of sieves, weighing the material retained on each sieve, and calculating the percentages passing and retained to obtain the gradation. The results are used to determine compliance with specifications and provide data for controlling aggregate production and mixtures. The method is not applicable to materials finer than 75 microns.
The experiment investigated the characteristics of a reverse osmosis membrane system with one, two, and three membranes. A calibration curve was generated to relate conductivity to salt concentration. For a single membrane, the water permeability was found to be 0.245 g/s-psi-m2 and the salt rejection coefficient was 0.879 on average. The salt mass transfer coefficient was 15.248 m/s. For two membranes, the second membrane had a lower rejection coefficient due to its more concentrated feed. The third membrane in a three membrane system had an even lower rejection coefficient. Overall, the rejection coefficient decreased as more membranes were added due to increasing feed concentration.
Setting Time of Hydraulic Cement By Vicat Needle | Jameel AcademyJameel Academy
This report details an experiment to determine the initial and final setting times of a hydraulic cement using the Vicat needle test method. The cement paste was prepared and tested according to ASTM standards. The initial setting time was found to be 2 hours and 45 minutes when the needle penetration was 6 mm. The final setting time was then calculated using an empirical equation to be 4 hours and 48 minutes. While only two penetration measurements were taken, the results indicate the cement would be suitable for construction uses and meet the Iraqi standard of a minimum 1 hour initial setting time.
Liposomes are spherical vesicles composed of concentric bilayer membranes made of phospholipids that can encapsulate aqueous solutions. They range in size from 20nm to several micrometers. Liposomes provide advantages for drug delivery such as increased drug efficacy, reduced toxicity, and passive tumor targeting. Common methods for preparing liposomes include physical dispersion, solvent dispersion, and detergent solubilization. Liposomes are evaluated based on properties like size, surface charge, drug encapsulation efficiency, and release kinetics. They have applications in drug delivery, antimicrobial and antiviral therapies, immunology, and cosmetics.
This study developed liposomes with varying cholesterol content for controlled pulmonary drug delivery. Liposomes were prepared with phospholipids and different ratios of cholesterol (12.5%, 25%, 50%) using lipid film hydration. Theophylline was encapsulated at different concentrations and entrapment efficiency was measured. Liposomes with higher cholesterol had higher entrapment efficiency, up to 29.4% for 50% cholesterol. In vitro drug release was tested over 24 hours, showing that higher cholesterol led to more sustained release - 50% cholesterol released only 20% of drug at 7 hours while lower cholesterol formulations released drug more quickly. In conclusion, cholesterol improves liposome stability and loading capacity while providing controlled release of an encapsulated drug.
This document discusses polymeric micelles for drug delivery applications. It explains that amphiphilic polymers can self-assemble above a critical micelle concentration to form micelles with a hydrophobic core and hydrophilic shell. Doxorubicin-loaded polymeric micelles were developed using poloxamer 407, with sizes around 23 nm and high drug encapsulation. The micelles were modified to attach two FLT3 peptides, CKR and EVQ, to target leukemic stem cells and increase cytotoxicity compared to free doxorubicin. These peptide-conjugated polymeric micelles show potential as a targeted drug delivery system for acute myeloid leukemia treatment.
Liposomes are artificially created spherical vesicles made of phospholipids and cholesterol that can encapsulate both hydrophilic and hydrophobic drugs. They are promising drug delivery systems due to their biocompatibility and ability to selectively target tissues. Liposomes vary in size from 20-5000 nm and consist of one or more phospholipid bilayers surrounding an aqueous core. There are several methods for preparing and loading drugs into liposomes to develop drug delivery systems with benefits like increased drug efficacy, stability and reduced toxicity.
Liposomal formulation by factorial design approach By Pranav Lendhey 36PranavLendhey
1. The document presents information on liposomal formulations and their preparation using a factorial design approach. Liposomes are spherical vesicles made of lipids that can be used to deliver drugs. Factorial design allows investigation of how formulation factors independently and interactively affect dependent variables like encapsulation efficiency and drug deposition.
2. A 32 factorial design was used to prepare liposomes from phospholipids and cholesterol, encapsulating Vitamin E. The design studied the effects of phospholipid amount and cholesterol amount on vesicle size, encapsulation efficiency, and drug deposition in rat skin.
3. The best performing liposomes based on drug deposition were selected for further formulation into gels using Carbopol polymer. The liposomal gel showed potential
This document discusses targeted drug delivery systems. It begins by explaining the concept of targeted drug delivery, which aims to direct drugs only to their site of action to provide maximum therapeutic effects while reducing toxicity. It then discusses various drug carrier systems used for targeted delivery, including nanoparticles, liposomes, microcapsules, and vesicles. In particular, it focuses on liposomes, describing their composition, morphology, advantages, and methods of formulation including mechanical dispersion, solvent dispersion, and detergent removal.
Liposomes are spherical vesicles composed of phospholipid bilayers that can encapsulate drugs. They were first described in 1961 and range in size from 20nm to 10um. Key advantages include biocompatibility, ability to deliver both hydrophobic and hydrophilic drugs, and providing protection of encapsulated drugs. Production costs are high and leakage of drugs can occur. Liposomes are formulated using phospholipids and cholesterol and can be classified based on their structure and size. They allow targeted and sustained drug delivery to tissues.
Liposomes are spherical vesicles made of phospholipid bilayers that can encapsulate aqueous content. There are three main types - MLV, SUV, and LUV. Liposomes are useful for drug delivery as they can encapsulate both hydrophilic and hydrophobic drugs and release them in a targeted manner. Key properties like size, size distribution, drug encapsulation efficiency, and drug release kinetics must be characterized to ensure quality of liposomal formulations for drug delivery applications. Various microscopic and analytical techniques are used to characterize these properties of liposomes.
Liposomes are spherical vesicles composed of phospholipid bilayers that can encapsulate drugs. They were invented in 1965 and have various applications in biology, biochemistry, pharmacy, and therapeutics. In pharmacy, liposomes were initially used in the 1970s-1980s and stealth liposomes with polyethylene glycol (PEG) coatings were developed in the 1990s to evade the immune system. Liposomes can be classified based on lamellarity (unilamellar vs multilamellar), size (small, large, giant), and preparation technique. Drugs are encapsulated within the aqueous core or bilayer of liposomes for drug delivery.
1. Liposomes are spherical vesicles made of concentric phospholipid bilayers that can encapsulate aqueous solutions. They form spontaneously when phospholipids are exposed to aqueous solutions.
2. Liposomes have many advantages for drug delivery such as increased drug efficacy, stability, and targeting to tumor tissues while reducing toxicity. However, they also have disadvantages like high production costs, drug leakage, and short half-life.
3. There are various methods for preparing and loading drugs into liposomes, including mechanical dispersion techniques using sonication or extrusion to reduce liposome size, and solvent dispersion techniques using thin film hydration. Characterization and stability testing of the liposomes is important.
Liposomes are spherical vesicles that can be used to deliver drugs in the body. They consist of lipid bilayers that encapsulate an aqueous core, allowing both hydrophilic and hydrophobic drugs to be carried. Liposomes have several applications in drug delivery such as improving drug solubility, providing sustained release, and increasing intracellular drug levels. However, stability, sterilization, and drug leakage pose challenges to their use. Currently, liposomal formulations of doxorubicin and amphotericin B are approved to deliver these drugs while reducing toxicity.
This document summarizes the use of liposomes in cancer therapy. It discusses that liposomal drug delivery can help overcome the side effects of traditional cancer treatments like chemotherapy by encapsulating drugs in liposomes. Liposomes preferentially accumulate in tumor tissues due to their leaky blood vessels and prolonged circulation time, allowing anticancer drugs to target cancer cells with less effect on healthy cells. The document provides details on the structure of liposomes and how their bilayer membrane can encapsulate both hydrophobic and hydrophilic drugs for delivery to cancer sites.
Liposomes are spherical vesicles composed of phospholipid bilayers that can encapsulate hydrophilic or hydrophobic drugs. There are several types of liposomes including conventional, stealth, targeted, and cationic liposomes. Liposomes can be prepared using techniques like extrusion, sonication, and dehydration-rehydration. Differential scanning calorimetry is used to study the phase transition of lipids in liposomes. Drugs are encapsulated within the aqueous core or phospholipid bilayer of liposomes. In vivo, liposomes are targeted by plasma proteins and cleared by the liver and spleen, but PEGylation creates "stealth liposomes" that evade this clearance. Several liposomal drug formulations have been commercial
ROLE OF LIPOSOME IN NOVEL DRUG DELIVERY SYSTEMDeepikshaSahu1
Liposomes are microscopic vesicles composed of a bilayer of phospholipids that can encapsulate both hydrophilic and lipophilic substances for drug delivery. Liposomes were discovered in 1965 as a drug delivery system and have received attention for delivering drugs to treat cancer and for gene delivery. Liposomes can be classified based on their composition, structure, and preparation method. They have advantages like biocompatibility and the ability to target drugs to specific cells, but also have disadvantages like high production costs and drug leakage. The document discusses the composition, properties, classification, advantages, and disadvantages of liposomes as a drug delivery system.
This document discusses liposomes and their role in novel drug delivery systems. It begins by defining liposomes as microscopic phospholipid vesicles that can encapsulate both hydrophilic and lipophilic substances. It then covers the classification of liposomes based on composition, structure, and preparation methods. The document discusses the advantages and disadvantages of liposomes for drug delivery. It also details the composition of liposomes including phospholipids and cholesterol. The mechanisms of liposome formation and various preparation methods are described.
This document provides an overview of liposomes including their discovery, composition, classification, preparation techniques, mechanisms of drug delivery, advantages, disadvantages, applications, market preparations, and prospects. It was submitted as an assignment on liposomes for an advanced pharmaceutical technology course. The key points covered include that liposomes were discovered in 1961, are composed primarily of phospholipids, can be classified based on size, number of bilayers, and composition/mechanism of delivery, and are prepared using various mechanical dispersion, solvent dispersion, and detergent removal techniques.
Liposomal drug delivery involves encapsulating drugs within liposomes, which are spherical vesicles composed of phospholipid bilayers, to improve drug targeting and reduce toxicity. Liposomes can be classified based on lamellarity, size, and method of preparation. Drugs are encapsulated within the aqueous interior or phospholipid bilayer of liposomes. Liposomes protect drugs, control drug release, and can be targeted to specific tissues. Applications include cancer therapy, antimicrobial delivery, ophthalmic delivery, and topical delivery to improve treatment.
The name liposome is derived from two Greek words: Lipo meaning “fat” and Soma meaning “body”.
Liposome are also defined as artificial microscopic vesicles consisting of aqueous compartment and surrounded by one or more concentric layer of phospholipid.
The sphere like interior encapsulates a liquid and also contain more substance like peptides, protein, hormones, enzymes, antibiotic, antifungal and anticancer agents.
This document discusses liposomes, which are spherical vesicles composed of phospholipid bilayers that can be used as drug delivery vehicles. It provides information on the structure of liposomes, including their components (phospholipids, cholesterol), classifications based on size and lamellarity, and characterization methods. Various types of liposomal drug delivery platforms are described, such as conventional liposomes, sterically stabilized liposomes, ligand-targeted liposomes, and combinations thereof. Methods for preparing liposomes include sonication, dissolving lipids in organic solvents, removing the solvents, and hydrating the lipids. Requirements for preparation and properties like phase transition temperature are also covered.
Liposomes are spherical vesicles composed of lipid bilayers that can encapsulate aqueous content. They are used as drug delivery systems to improve drug solubility, stability, and targeting. Liposomes are prepared using various methods involving dispersion of lipids in aqueous solution. Key components are phospholipids like phosphatidylcholine and cholesterol. Characterization evaluates parameters like size, shape, drug entrapment efficiency, and phase behavior. Liposomes offer benefits like increased drug efficacy and stability but also have challenges like short shelf life and high production costs.
1.
5 March, 2015
TO: Professor L. Zhang, Ph.D
FROM: Group A-7
SUBJECT: Liposome Nanoparticle Synthesis, Final Report
Please find attached the final report of the evaluation liposome nanoparticles under varying cholesterol
concentrations. The report includes the analysis of the average size and polydispersity index of liposomes
prepared using the extrusion method.
If questions or concerns arise, please feel free to contact us at your convenience.
Sincerely,
Group A-7
Adam Rice, Part I
Minh Dao, Part II
Chris Mase, Part III Hong Zhang, Part IV
2.
Liposome Nanoparticles
Chris Mase, Hong Zhang, Adam Rice, Minh Dao
The goal of this experiment was to synthesize liposome nanoparticles using the extrusion method to
maintain an average size of 100 nm with a low polydispersity index, which indicates a more homogenous
solution. The amount of lipid (DLPC) and the number of extrusions remained constant while the amount
of cholesterol was varied in four samples. We found that when the cholesterol amount increased, the
polydispersity index of the liposome solution decreased. This is likely due to the ability of cholesterol to
incorporate itself into the liposome bilayer and stabilize it. There was no correlation between the amount
of cholesterol and liposome size. The best results were obtained with the liposome solution containing
25% cholesterol, which had a PDI of 0.19 ± 0.04 with a particle size of 140 ± 10 nm.
Advisor: Professor Liangfang Zhang
March 6, 2015
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Introduction
Liposomes were described by Akbarzadeh et al. as artificial spherical vesicles composed of
cholesterol and natural phospholipids, formed by the hydrophilic and hydrophobic interactions of the
phospholipid bilayer in aqueous solutions.1
Different preparation techniques lead to different properties,
which allows for the customization of vesicle bilayers, size, surface properties, and composition.
Liposomes form when amphiphiles, which are surface molecules with a hydrophilic head group and
hydrophilic tail group, are exposed to water and form lipid bilayer compartments which can entrap
molecules in different areas. Addition of cholesterol contributes to the stability and fluidity of the bilayer,
while the size of vesicles can be controlled by extrusion through a membrane of desired pore size.
Adjustment of these characteristics can provide an optimal environment for the transport of a desired
molecule.
Due to their characteristics, liposomes have been seen as promising vehicles for drug
transportation and delivery. Their hydrophobic and hydrophilic properties allow for the incorporation of
drugs on the surface from electrostatic interactions or entrapped within the vesicle.2
Encapsulation of
drugs allows them to be protected from degradation before they reach their target area. A more focused
drug delivery is achieved by incorporating surface molecules with an affinity for the delivery site. This
allows for minimal drug dispersal throughout the body which will reduce harmful side effects of the drug
in other areas. This is promising for cancer treatments in which toxic medications would be much more
effective if a higher dose can reach the target site and not spread throughout the body causing damage to
other areas sensitive to the drug.
Another application of liposome nanoparticles is the treatment of the bacterium which causes
acne, Propionibacterium acnes, with the antimicrobial properties of lauric acid (LA). Yang et al. have
demonstrated the effectiveness of LA loaded liposomes in the treatment of acne in which liposomes aid in
the delivery and enhancement of antimicrobial activity.3
This is partly due to the similarities between lipid
composition and the epidermis, allowing the liposomes to be very effective in treatment of hair follicle-
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associated disorders.3
This shows the flexibility of liposome mediated treatments for diseases and the
limitations due to their composition as well as drug properties.
This experiment involved the synthesis of liposomes using cholesterol and DLPC with extrusion
through a 100 nm membrane to control their size distribution. The ratio of cholesterol to DLPC was
varied to produce different properties in the liposomes. This was done to observe the effects of the
varying cholesterol on liposome properties that can be measured by dynamic light scattering (DLS). The
goal was to produce liposomes of around 100 nm with an acceptable polydispersity index (PDI) range
between 0.1 and 0.25.4
Background and Theory
Haematologist Alec Bangham discovered liposomes in 1961 when he was testing an electron
microscope on phospholipids at the Babraham Institute.5
Liposomes then became extremely popular in
industry once Alec’s report on Liposomes went public roughly five years later. Liposomes are
phospholipid bilayers, much like cells. Liposome nanoparticles are useful in medicine because of this.
Liposomes are commonly used to protect soluble drugs en route to the desired destination. This
can be most easily explained with extremely harmful Chemo Therapy drugs. While this has not been
perfected yet, the idea is to allow the nanoparticles to carry the highly toxic Chemo drug directly to the
source of the cancer, exclusively killing the cancer, and not healthy cells. The reason liposomes are
commonly tasked for this is because of the hydrophilic head of the outer shell, allowing the liposome to
dissolve, and the hydrophobic bilayer protecting the soluble inner core of the liposome. This creates a
protective shell around anything the liposome is encapsulating.
One of the main issues in using liposomes is hydrating. Hydrating the liposome allows the
structure to expand, and allows drugs to be absorbed into the structure, so this is vital to the process.
However, over hydrating makes the liposome too large to intake into the body. The human blood stream
can most efficiently absorb liposomes in a range of 100-150 nm.
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In order to efficiently attain this range of liposomes, the hydrated solution is agitated using sound
to break up multilamellar vesticles (MLV) into smaller nanoparticles. After agitation, liposomes are
commonly extruded through a membrane to restrict diameter to a large unilamellar vesticle (LUV) size of
roughly 100nm.
Figure 1: Size comparison between LUVs and MLVs.
Sizes of liposomes are commonly determined through a Dynamic Light Scanning (DLS) system,
which measures the intensity of the light scattered by the molecules versus time. This correlation is used
to determine the diameter of the sample. The diffusion coefficient (D) is compared to radius (R) through
the Stokes equation (1).
(1)
Where k is the Boltzman constant, T is temperature, and η is viscosity. In order to obtain this diffusion
coefficient, the intensity correlation mentioned earlier must be analyzed(6)
. By fitting a polynomial to the
intensity function, the decay function (or decay rate) is found:
(2)
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This relates the decay of intensity directly to the diffusion coefficient. q is the wave vector, which relies
on the scatter angle.
Finally, distribution of size is important to note. This distribution is known as the polydispersity
index (PDI). The PDI measures the width of the bell curve obtained in intensity versus diameter plot. The
PDI can be calculated by equation (3).
(3)
Where σ is the standard deviation, and dH is the diameter. Because PDI measures the width of the
distribution curve, the larger PDI is, the larger the distribution of diameters.
Methods
Solutions provided by the TA included a 5mL of 10mg/mL phospholipid/chloroform (DLPC),
5mL of 10mg/mL cholesterol/chloroform, and a chloroform solution. From these, four solutions were
prepared using 450 uL of DLPC, 50-150 uL of cholesterol (resulting in 10, 14.3, 20, and 25%
cholesterol), and the remaining volume chloroform for a final volume of 2.025 mL. The solutions were
then mixed and placed under a nitrogen stream for around 35 minutes to evaporate the chloroform solvent
until a thin lipid film remained. The solutions were rehydrated with 3 mL of distilled water and placed in
a sonicator for 5 minutes to agitate the solution and ensure thorough mixing. Once agitated, 1 mL of
solution was transferred to a syringe and filtered through a Nucleopore 100 nm polycarbonate membrane
11 times. Two trials for each sample were extruded. The membrane and 4 spacers which held it in place
were soaked in distilled water prior to the filtration. The remaining solution in the syringe was then
transferred to a cuvette along with distilled water and set aside to analyze in the DLS at the end of the lab
period. DLS reading measured a sample three times with eleven runs during each measurement.
Results & Discussion
The initial hypothesis of this experiment assumes that higher cholesterol content would stabilize
the membranes of synthesized liposomes and thus, reduce the probability of aggregation. It was expected
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that the addition of cholesterol would cause a sample to be less polydisperse as more multilamellar
vesicles (LMVs) are converted to unilamellar vesicles (LUVs). In turn, the size of the sample would
decrease until it reaches a size of 100 nm with a PDI range between 0.1 and 0.25. This would show that
higher cholesterol content induces the formation of homogeneous liposome sample. Varied cholesterol
contents and other characteristics of four prepared samples were recorded in Table 1 of the Appendix.
Dynamic Light Scattering (DLS) technique measured the average diameter sizes and
polydispersity index (PDI) found in Table 2 of the Appendix. Figure 2 graphically relates the cholesterol
percentage of 10%, 14%, 20%, and 25% to the average diameter sizes of the synthesized liposomes.
Figure 2. Effect of varying cholesterol content on average diameter size
When the sample had a cholesterol content of 14% and 20%, the average diameter size was at its
lowest of 118 nm. Meanwhile, at the cholesterol percentage of 25%, the average diameter size of
liposomes was at its highest at 140 ± 10 nm. While the increase in cholesterol percentage from 10% to
14% decreased the average diameter size by nearly 14 nm, the result did not show that an increase in
cholesterol content decreases the average diameter of synthesized particles as expected. Rather, no
correlation was drawn from graphical evaluation.
Lab techniques can be used to explain why this result did not meet expectation. During the
extrusion process of a sample with 14% cholesterol, nearly most of the sample was lost due to leakage. In
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doing so, only two trials were implemented with three and nine extrusions. Therefore, point 2 of Figure 2
does not accurately reflect the effect of varying cholesterol content on synthesized liposomes since
another variable, the number of extrusion, was changed during data collection. Even though this sample
was included in Figure 1 and 2, it is important to note that this data point was disregarded during later
analysis due to the mentioned reason. Meanwhile, in Figure 1, point 4 representing a sample of 25%
cholesterol produced a high diameter size due to contamination when extruding the sample. It was
observed during data collection that one plunger of the extruder was loose. This allowed sample that was
not extruded to seep through the end of the syringe and cause contamination. In effect, the sample
containing 25% cholesterol had a large particle size.
The increase of cholesterol content led to the decrease in PDI of synthesized liposomes. As seen
in Figure 2, cholesterol percentage of 10% produced the highest PDI of 0.33 ± 0.05, which is outside the
acceptable PDI range of 0.1 and 0.25. This indicates that the sample contained polydisperse liposomes
that were unilamellar and multilamellar vesicles. Thus, the size distribution of the sample was large.
Figure 3. Effect of varying cholesterol content on PDI
When cholesterol percentage was increased from 10% to 20% and 25%, PDI values decreased
and moved inside the acceptable PDI range between 0.1 and 0.25. This denotes that the size distributions
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of these two samples are narrow. A narrow size distribution illustrates that the increase in cholesterol
content stabilizes the structure of liposomes. This enables more liposomes which are LUVs to be
synthesized and thus, the size distribution within a sample becomes more uniform.
The measured PDI values support intensity reading obtained from the DLS technique. Graphical
evaluation of Figure 4 illustrates how a cholesterol increase leads to a higher intensity reading, where
intensity is the amount of light scattered by a particle at a specific diameter size.
Figure 4. Intensity with varying cholesterol contents
In the above figure, the sample containing 25% cholesterol produced the highest curve with an
intensity of approximately 12 compared to the other lower cholesterol samples. Additionally, the intensity
curve also becomes narrower with the increase in cholesterol content. Therefore, similar to the measured
PDI values in Figure 3, the intensity readings of tested samples show that increasing cholesterol content
decreases the size distribution of a sample. This is because cholesterol stabilizes the structure of LUVs
that are formed enabling the sample to become more uniform in size.
Conclusion
In this experiment, the average particle size and polydispersity index were examined in four
samples in which the cholesterol percentage was varied while the amount of DLPC, total volume of
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solution, and number of extrusions were kept constant. Results showed that the change in cholesterol had
an effect on the polydispersity index but no correlation with the size of the particles. The best results were
obtained with the lowest polydispersity index of 0.19 ± 0.04 and particle size of 140 ± 10 nm from the
solution with the highest cholesterol percentage tested, which was 25%. For future experiments the
number of extrusions could be varied in order to study its effect on size and size distribution.
References
1. Akbarzadeh A.; Davaran S.; Rezaei-Sadabady R.; et al. Liposome: classification, preparation, and
applications. Nanoscale Research Letters 2013, 8(102), 1-9.
2. Gregoriadis G.; Perrie Y., Liposomes. Encyclopedia of Life Sciences 2010, 1-8. DOI:
10.1002/9780470015902.a0002656.pub2
3. Yang, D. R.; Pornpattananangkul, D.; Nakatsuji, T.; Chan, M.;Carson, D.; Huang, C. M.; Zhang, L.,
The antimicrobial activity of liposomal lauric acids against Propionibacterium acnes. Biomaterials 2009,
30, 6035-40.
4. Bahareh Sabeti, Mohamed Ibrahim Noordin, Shaharuddin Mohd, Rosnani Hashim, Afendi Dahlan, and
Hamid Akbari Javar, “Development and Characterization of Liposomal Doxorubicin Hydrochloride with
Palm Oil,” BioMed Research International, vol. 2014, Article ID 765426, 6 pages, 2014.
doi:10.1155/2014/765426.
5. Bangham, A. D.; Horne, R. W. (1964). "Negative Staining of Phospholipids and Their Structural
Modification by Surface-Active Agents As Observed in the Electron Microscope". Journal of Molecular
Biology 8 (5): 660–668.
6. DYNAMIC LIGHT SCATTERING dynamic light scattering common terms defined. Inform White
Paper. 2011;2015 (02/02):1-6. LS Instruments
http://www.lsinstruments.ch/technology/dynamic_light_scattering_dls/.
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Appendix
Concentration Sample 1 Sample 2 Sample 3 Sample 4
DLPC (µL) 450 450 450 450
Cholesterol (µL) 50 75 113 150
Chloroform (µL) 1525 1500 1463 1425
Volume (µL) 2025 2025 2025 2025
Cholesterol (%) 10 14.3 20 25
Cholesterol Content (%) Mean Diameter ± StDev (nm) PDI
10 132 ± 4 0.33 ± 0.05
20 118 ± 5 0.25 ± 0.05
25 140 ± 10 0.19 ± 0.04
Table 1. Concentrations of DLPC, cholesterol, and chloroform in the
prepared samples. The concentration of DLPC was maintained at 2.25
mg/mL. The number of extrusion in all samples except Sample 2 was 11.
The amount of solvent added after dehydration was 3 mL.
Table 2. Average particle diameter and PDI values from varying
cholesterol contents.
12.
4 March, 2015
TO: Professor L. Zhang, PhD
FROM: Group A-7
SUBJECT: Technical memorandum regarding reverse osmosis
Our group proposes to perform the reverse osmosis experiment. Reverse osmosis is a water
purification technology that has wide applications in areas such as drinking water production, and
waste remediation processes. The object of the experiment is to study the effect of pressure drop and
flow rate of inlet water on the performance of reverse osmosis system. The performance of the
reverse osmosis system is indicated by rejection coefficient and recovery under steady states. We will
perform experiments measuring those two parameters with one and two membranes reverse osmosis
system separately, with the varying parameters being the applied pressure, and flow rate. We
hypothesis that higher pressure drop would increase the performance of the system because higher
pressure drives the permeability of water through membrane. Also, two-membrane reverse osmosis
system would have an overall better performance. We will then design a reverse osmosis system with
retentate recycle, and compare its performance with design estimations generated from material
balance calculations. If you have any questions or concerns, please feel free to contact me.
Sincerely,
Hong Zhang