This presentation gives a summary on the development of the Cambridge Trimaster which is an apparatus for studying the fast filament stretching, thinning and break up of low viscosity fluids. The apparatus is particularly relevant to ink jet fluids
This document summarizes research on liquid-like thin films conducted by Alokmay Datta and collaborators. Key points include:
1. Langmuir monolayers of stearic acid with cadmium ions exhibit irreversible fracture like a solid, while with cobalt ions they spread out and reconnect like a liquid upon decompression and recompression.
2. Monolayers of stearic acid on a solid surface with cadmium ions exhibit self-affine height correlations characteristic of a solid, while with cobalt ions they show logarithmic correlations characteristic of a liquid.
3. Neutral polymer films like polystyrene below a thickness of about the polymer radius of gyration arrange in
Simon Fraser University researchers developed novel polymer membranes for fuel cells. They synthesized fluoropolymer-block-ionic and fluorous-ionic graft copolymers with different architectures. The membrane morphology, including ionic channel size and continuity, depended on polymer structure and affected properties like water uptake and proton conductivity. Fully sulfonated membranes showed continuous increases in proton conductivity with ion exchange capacity, while partially sulfonated membranes peaked at moderate capacities due to conductivity drops at high capacities. The graft structure allowed high capacities without dissolution, promising for low-humidity proton conductivity needed in fuel cells.
1) The document describes a computational fluid dynamics (CFD) model developed to simulate the melting of ice particles under natural convection.
2) The model uses a direct numerical simulation (DNS) approach coupled with subgrid models to relate heat transfer between the fluid and solid particles. Key aspects of the numerical model are described.
3) The model is validated against experimental data on melting ice spheres and cylinders. Simulation results match well with the experimental melting rates.
The document discusses using core data from carbonate rock samples to model NMR well log responses. It contains core data like T1 and T2 distributions from NMR experiments on different carbonate rock types. This data is used to simulate raw NMR well logs by matching acquisition parameters and modeling fluid properties. Fluid substitution and inversion modeling are also used to evaluate fluid identification and the effect of acquisition settings on interpretation. The goal is to calibrate well log NMR data using the detailed core measurements and better understand NMR responses in carbonate reservoirs.
The document discusses volume-phase transitions in surface-tethered polymer networks and their implications for swelling instabilities. It finds that surface attachment prevents polymer networks from achieving their zero-stress state, resulting in higher linear deformation compared to unconstrained networks. It also examines how crosslinking density and monomer structure can affect the phase behavior and transition properties of these surface-attached networks.
91 92. june 9 overview febex-dp-and_ufd r&d activities related to febex-d...leann_mays
The document summarizes research from the FEBEX-DP collaboration which studied the dismantling of heaters from an in situ heating test of bentonite clay at the Grimsel Test Site in Switzerland. Key findings include:
1) Coupled THMC modeling of the experiment showed reasonable matches to observed temperature, relative humidity, water content, stress, and chloride concentration over time.
2) Synchrotron X-ray microtomography measurements characterized the microstructure and crack network in bentonite clay samples.
3) Initial characterization of the bentonite-concrete interface by SEM-EDS showed cracks abundant at the interface but no strong elemental gradients beyond the interface region.
4) Ongoing work
This document summarizes research on liquid-like thin films conducted by Alokmay Datta and collaborators. Key points include:
1. Langmuir monolayers of stearic acid with cadmium ions exhibit irreversible fracture like a solid, while with cobalt ions they spread out and reconnect like a liquid upon decompression and recompression.
2. Monolayers of stearic acid on a solid surface with cadmium ions exhibit self-affine height correlations characteristic of a solid, while with cobalt ions they show logarithmic correlations characteristic of a liquid.
3. Neutral polymer films like polystyrene below a thickness of about the polymer radius of gyration arrange in
Simon Fraser University researchers developed novel polymer membranes for fuel cells. They synthesized fluoropolymer-block-ionic and fluorous-ionic graft copolymers with different architectures. The membrane morphology, including ionic channel size and continuity, depended on polymer structure and affected properties like water uptake and proton conductivity. Fully sulfonated membranes showed continuous increases in proton conductivity with ion exchange capacity, while partially sulfonated membranes peaked at moderate capacities due to conductivity drops at high capacities. The graft structure allowed high capacities without dissolution, promising for low-humidity proton conductivity needed in fuel cells.
1) The document describes a computational fluid dynamics (CFD) model developed to simulate the melting of ice particles under natural convection.
2) The model uses a direct numerical simulation (DNS) approach coupled with subgrid models to relate heat transfer between the fluid and solid particles. Key aspects of the numerical model are described.
3) The model is validated against experimental data on melting ice spheres and cylinders. Simulation results match well with the experimental melting rates.
The document discusses using core data from carbonate rock samples to model NMR well log responses. It contains core data like T1 and T2 distributions from NMR experiments on different carbonate rock types. This data is used to simulate raw NMR well logs by matching acquisition parameters and modeling fluid properties. Fluid substitution and inversion modeling are also used to evaluate fluid identification and the effect of acquisition settings on interpretation. The goal is to calibrate well log NMR data using the detailed core measurements and better understand NMR responses in carbonate reservoirs.
The document discusses volume-phase transitions in surface-tethered polymer networks and their implications for swelling instabilities. It finds that surface attachment prevents polymer networks from achieving their zero-stress state, resulting in higher linear deformation compared to unconstrained networks. It also examines how crosslinking density and monomer structure can affect the phase behavior and transition properties of these surface-attached networks.
91 92. june 9 overview febex-dp-and_ufd r&d activities related to febex-d...leann_mays
The document summarizes research from the FEBEX-DP collaboration which studied the dismantling of heaters from an in situ heating test of bentonite clay at the Grimsel Test Site in Switzerland. Key findings include:
1) Coupled THMC modeling of the experiment showed reasonable matches to observed temperature, relative humidity, water content, stress, and chloride concentration over time.
2) Synchrotron X-ray microtomography measurements characterized the microstructure and crack network in bentonite clay samples.
3) Initial characterization of the bentonite-concrete interface by SEM-EDS showed cracks abundant at the interface but no strong elemental gradients beyond the interface region.
4) Ongoing work
Magnetic chitosan nanoparticles for removal of cr(vi) from aqueous solutionhbrothers
This document describes research on using magnetic chitosan nanoparticles for removing Cr(VI) from aqueous solutions. The researchers introduced a simple method to prepare magnetic chitosan nanoparticles via co-precipitation and epichlorohydrin cross-linking. Characterization showed the nanoparticles were spherical and around 30 nm in size. Adsorption experiments found Cr(VI) removal was highly dependent on pH, with maximum adsorption of 55.80 mg/g occurring at pH 3. Kinetic data fit a pseudo-second order model and isotherm data fit the Langmuir model well. The magnetic chitosan nanoparticles showed potential for use in wastewater treatment applications to remove Cr(VI).
The document describes a study on separating minor actinides from simulated high-level nuclear waste using hollow fiber supported liquid membranes (HFSLM) and non-dispersive solvent extraction (NDSX). It presents the motivation, objectives, and overview of the research, which includes developing a mathematical model to represent metal ion transport across HFSLM and NDSX processes. The document then provides details on the HFSLM experimental setup and transport mechanism, and describes the development of a permeability-based model for HFSLM that is validated against experimental data on extracting neodymium ions using TODGA as the extractant.
Invited lecture of the Simposium N "Surface Engineering - functional coatings and modified surfaces" at the XIII SBPMat (Brazilian MRS) meeting, in João Pessoa (Brazil). The lecture took place on September 29th, 2014.
The speaker was Christopher Muratore, "Wright Brothers Institute Endowed Chair Professor" at the Department of Chemical and Materials Engineering from University of Dayton (USA).
Flow, Crystallisation and Continuous Processingmalcolmmackley
This presentation reviews the way flow can effect crystallisation. The presentation also reviews different ways continuous processing can be achieved. Continuous crystallisation is of relevance to a number of technologies including pharmaceutical manufacture.
This document discusses the design and operation of molecular rotary motors at interfaces. It describes:
1) How rotary motors in biology inspired the design of an artificial molecular rotor with a photoisomerizable double bond that undergoes a light-driven unidirectional rotary cycle.
2) Methods explored to control the speed of rotation, attach the motors to surfaces, and demonstrate light-driven rotary motion of surface-bound motors.
3) Efforts to utilize the rotary motion to perform work, such as stirring molecules at the interface, which could enable applications if the random motion of the motors can be confined and directed.
27a febex dp collaboration overview and related sfwst r and d activities zhen...leann_mays
The document summarizes research from the FEBEX-DP collaboration studying the full-scale FEBEX bentonite experiment located in Grimsel, Switzerland. It discusses characterization of the bentonite following dismantling of heater #2, including changes to density, water content, mineralogy, and pore water chemistry. THM and THMC models were developed and validated against experimental data to analyze thermal-hydrological-mechanical and chemical processes. Microstructural analysis using synchrotron X-ray microCT provided 3D characterization of the bentonite microstructure. Further work is focused on refining chemical models, analyzing gas evolution and microbial activity, and characterizing the bentonite-concrete interface.
The document discusses the benefits of exercise for mental health. Regular physical activity can help reduce anxiety and depression and improve mood and cognitive function. Exercise causes chemical changes in the brain that may help alleviate symptoms of mental illness and boost overall mental well-being.
This document summarizes research on electrostatic complexes in polymer materials science. It discusses using non-covalent interactions like π-stacking, coordination via metals, and hydrogen bonding to build supermolecular structures from polymer assemblies. It also describes techniques like layer-by-layer assembly and complex coacervation to encapsulate and pattern materials. The research aims to better understand parameters affecting polyelectrolyte brush structures and interactions through experiments using surface force apparatus.
This document discusses the sol-gel synthesis and characterization of Titania-Zirconia matrices doped with rare earth ions and CdS. Chapter 1 provides a general introduction to sol-gel processing and its advantages. Chapter 2 discusses the spectroscopy of Tb3+ and Eu3+ ions in the Titania-Zirconia matrix. Chapter 3 details the structural and optical characterization of CdS/Tb3+/Eu3+ doped Titania-Zirconia matrices prepared via sol-gel processing. Various characterization techniques were used to analyze the materials' structure, composition, and optical properties.
- The document discusses using a flame synthesis technique called flame stabilization on a rotating surface (FSRS) to produce TiO2 nanoparticles and thin films for use in dye-sensitized solar cells (DSSCs).
- FSRS allows for one-step particle synthesis and film deposition, controlling properties like particle size and crystal phase that impact DSSC efficiency. DSSCs made with FSRS-produced films show efficiencies up to 7.6%.
- Parameters like particle size, crystal phase, thickness, and surface area can be controlled in FSRS and significantly impact DSSC performance. Smaller particles and the anatase crystal phase produce higher photocurrents and efficiencies.
The document discusses investigation of hexagonal boron nitride (BN) using terahertz time-domain spectroscopy. The analysis revealed differences in refractive indices and transmission loss between four grades of hot pressed BN related to their porosity and binder content. It also provided an indication of particle and pore sizes. Terahertz time-domain spectroscopy was shown to provide structural insight into opaque ceramic materials like various grades of BN.
This document presents a lattice Boltzmann model for simulating dendritic growth under natural convection. It validates the natural convection model for a heated cavity by comparing the temperature profiles to other models. The document then uses the lattice Boltzmann model to simulate equiaxed and columnar dendrite growth under natural convection and observes how convection alters the growth patterns and solute distribution. It also simulates the formation of micro-segregated channels that can lead to freckling defects during solidification of alloys.
The document describes a 3D numerical model developed to better understand freckle formation in metallic alloys during solidification. Freckles are channel-like micro-segregation defects that degrade mechanical properties. The model uses lattice Boltzmann and cellular automaton methods to simulate convective fluid flow, heat transfer, and solute redistribution during solidification. Simulation results show that buoyancy-induced fluid flow alters dendrite growth kinetics and solute distribution, potentially leading to freckle formation through competition between dendrites.
The properties of rattan cane and its comprehensive utilization technology. Presented by Xinge liu, Shumin Yang, Lili Shang, and Jianfeng Ma, researchers at the International Centre for Bamboo and Rattan. Presented at the ASEAN Rattan Summit.
SCR and TTR modeling using shell and beam elements to deal with local interests, such as touch-down compression or buckling. Two examples are presented. The FEA tool employed is ABAQUS. Videos can only be seen when downloaded.
Werner Kuhn and Hans Kuhn were brilliant 1940s Swiss polymer scientists who developed theories on random coil statistics and entropy of polymer chains. Their work provided a foundation for understanding rubber elasticity. Andrew Keller, a 1950s-1970s Hungarian physical chemist, made important contributions to understanding polymer crystallization through his work on polyethylene single crystals. Pierre de Gennes, a prominent 20th century French physicist, applied his expertise in areas like superconductivity to develop the theory of polymer reptation. Piet Lemstra and Paul Smith were 1980s Dutch polymer scientists who successfully produced high modulus polyethylene through solution processing techniques.
The document discusses numerical simulations of ablation patterns on sublimating materials. It summarizes previous research on crosshatch patterns and experiments by Stock. The approach involves using CFD tools to implement a non-trivial boundary condition for low-temperature ablator camphor. Validation simulations of Baker's experiments on camphor cones show good agreement. Preliminary 3D simulations with turbulent models show localized groove patterns developing from peaks in wall temperature. Future work includes more detailed 3D cases and investigating the wall temperature dependence of groove formation.
Oral presenation AVS 2013 Liwang 10-25-13Liwang Ye
This document summarizes an in situ ATR-FTIR study of TiO2 and HfO2 atomic layer deposition (ALD) on GaAs surfaces. Isotope exchange experiments during TiO2 ALD identified methylmethyleneimine (MMI) as being produced during water exposures and accumulating in the film. Higher temperature ALD of HfO2 at 275°C showed removal of the native GaAs oxide layer, while lower temperature deposition at 200°C did not show significant removal. The study provides insight into surface reactions and film formation mechanisms during high-k dielectric ALD on III-V semiconductor materials.
Wollastonite is a naturally occurring calcium silicate mineral that has potential as a micro-reinforcement in cementitious materials. The presentation evaluated four grades of wollastonite fibers as a partial replacement for cement in mortar and paste mixes. Testing showed that wollastonite improves mechanical properties by reinforcing the brittle matrix at the micro-level. Smaller wollastonite fibers blended more efficiently with the matrix and provided greater improvements in strength and fracture toughness compared to coarser fibers. The addition of wollastonite reduced early-age plastic shrinkage cracking and improved long-term flexural strength, toughness, and compressive strength up to 60%, 140%, and 30% respectively. Hybrid fiber reinforcement
This document discusses using ultrafast lasers to drive plasma for space propulsion applications. Key points include:
- Lasers at the University of Michigan are being used to accelerate protons and deuterons from various target materials for propulsion. Proton beams up to 13 MeV have been observed.
- Target composition, thickness, and surface conditions can affect the maximum proton energy and beam profile. Filamentation in beam profiles resembles simulations of electron behavior.
- Future laser development aims to reach petawatt powers at 30-40 femtosecond pulses for high efficiency ion acceleration. Simulation models describe ion acceleration from laser-driven relativistic electron clouds.
This document discusses plastics and polyethylene (PE) specifically. It notes that while plastics are fantastic due to their diverse uses, low production costs, and material properties, they also have environmental downsides when not disposed of properly. PE has a wide range of microstructures that give it varying properties and uses. It is one of the world's largest commodities, with over 80 million tonnes produced annually for a huge diversity of applications. However, plastic waste in the environment is a current issue that requires better recycling and disposal practices.
This presentation gives a summary of how Polyethylene (PE). can crystallise from solution and the melt. The crystallisation of PE is both remarkable and very beautiful. The way PE crystallises is very important in relation to the properties of PE plastic bags, extrusions and high modulus PE fibres.
Magnetic chitosan nanoparticles for removal of cr(vi) from aqueous solutionhbrothers
This document describes research on using magnetic chitosan nanoparticles for removing Cr(VI) from aqueous solutions. The researchers introduced a simple method to prepare magnetic chitosan nanoparticles via co-precipitation and epichlorohydrin cross-linking. Characterization showed the nanoparticles were spherical and around 30 nm in size. Adsorption experiments found Cr(VI) removal was highly dependent on pH, with maximum adsorption of 55.80 mg/g occurring at pH 3. Kinetic data fit a pseudo-second order model and isotherm data fit the Langmuir model well. The magnetic chitosan nanoparticles showed potential for use in wastewater treatment applications to remove Cr(VI).
The document describes a study on separating minor actinides from simulated high-level nuclear waste using hollow fiber supported liquid membranes (HFSLM) and non-dispersive solvent extraction (NDSX). It presents the motivation, objectives, and overview of the research, which includes developing a mathematical model to represent metal ion transport across HFSLM and NDSX processes. The document then provides details on the HFSLM experimental setup and transport mechanism, and describes the development of a permeability-based model for HFSLM that is validated against experimental data on extracting neodymium ions using TODGA as the extractant.
Invited lecture of the Simposium N "Surface Engineering - functional coatings and modified surfaces" at the XIII SBPMat (Brazilian MRS) meeting, in João Pessoa (Brazil). The lecture took place on September 29th, 2014.
The speaker was Christopher Muratore, "Wright Brothers Institute Endowed Chair Professor" at the Department of Chemical and Materials Engineering from University of Dayton (USA).
Flow, Crystallisation and Continuous Processingmalcolmmackley
This presentation reviews the way flow can effect crystallisation. The presentation also reviews different ways continuous processing can be achieved. Continuous crystallisation is of relevance to a number of technologies including pharmaceutical manufacture.
This document discusses the design and operation of molecular rotary motors at interfaces. It describes:
1) How rotary motors in biology inspired the design of an artificial molecular rotor with a photoisomerizable double bond that undergoes a light-driven unidirectional rotary cycle.
2) Methods explored to control the speed of rotation, attach the motors to surfaces, and demonstrate light-driven rotary motion of surface-bound motors.
3) Efforts to utilize the rotary motion to perform work, such as stirring molecules at the interface, which could enable applications if the random motion of the motors can be confined and directed.
27a febex dp collaboration overview and related sfwst r and d activities zhen...leann_mays
The document summarizes research from the FEBEX-DP collaboration studying the full-scale FEBEX bentonite experiment located in Grimsel, Switzerland. It discusses characterization of the bentonite following dismantling of heater #2, including changes to density, water content, mineralogy, and pore water chemistry. THM and THMC models were developed and validated against experimental data to analyze thermal-hydrological-mechanical and chemical processes. Microstructural analysis using synchrotron X-ray microCT provided 3D characterization of the bentonite microstructure. Further work is focused on refining chemical models, analyzing gas evolution and microbial activity, and characterizing the bentonite-concrete interface.
The document discusses the benefits of exercise for mental health. Regular physical activity can help reduce anxiety and depression and improve mood and cognitive function. Exercise causes chemical changes in the brain that may help alleviate symptoms of mental illness and boost overall mental well-being.
This document summarizes research on electrostatic complexes in polymer materials science. It discusses using non-covalent interactions like π-stacking, coordination via metals, and hydrogen bonding to build supermolecular structures from polymer assemblies. It also describes techniques like layer-by-layer assembly and complex coacervation to encapsulate and pattern materials. The research aims to better understand parameters affecting polyelectrolyte brush structures and interactions through experiments using surface force apparatus.
This document discusses the sol-gel synthesis and characterization of Titania-Zirconia matrices doped with rare earth ions and CdS. Chapter 1 provides a general introduction to sol-gel processing and its advantages. Chapter 2 discusses the spectroscopy of Tb3+ and Eu3+ ions in the Titania-Zirconia matrix. Chapter 3 details the structural and optical characterization of CdS/Tb3+/Eu3+ doped Titania-Zirconia matrices prepared via sol-gel processing. Various characterization techniques were used to analyze the materials' structure, composition, and optical properties.
- The document discusses using a flame synthesis technique called flame stabilization on a rotating surface (FSRS) to produce TiO2 nanoparticles and thin films for use in dye-sensitized solar cells (DSSCs).
- FSRS allows for one-step particle synthesis and film deposition, controlling properties like particle size and crystal phase that impact DSSC efficiency. DSSCs made with FSRS-produced films show efficiencies up to 7.6%.
- Parameters like particle size, crystal phase, thickness, and surface area can be controlled in FSRS and significantly impact DSSC performance. Smaller particles and the anatase crystal phase produce higher photocurrents and efficiencies.
The document discusses investigation of hexagonal boron nitride (BN) using terahertz time-domain spectroscopy. The analysis revealed differences in refractive indices and transmission loss between four grades of hot pressed BN related to their porosity and binder content. It also provided an indication of particle and pore sizes. Terahertz time-domain spectroscopy was shown to provide structural insight into opaque ceramic materials like various grades of BN.
This document presents a lattice Boltzmann model for simulating dendritic growth under natural convection. It validates the natural convection model for a heated cavity by comparing the temperature profiles to other models. The document then uses the lattice Boltzmann model to simulate equiaxed and columnar dendrite growth under natural convection and observes how convection alters the growth patterns and solute distribution. It also simulates the formation of micro-segregated channels that can lead to freckling defects during solidification of alloys.
The document describes a 3D numerical model developed to better understand freckle formation in metallic alloys during solidification. Freckles are channel-like micro-segregation defects that degrade mechanical properties. The model uses lattice Boltzmann and cellular automaton methods to simulate convective fluid flow, heat transfer, and solute redistribution during solidification. Simulation results show that buoyancy-induced fluid flow alters dendrite growth kinetics and solute distribution, potentially leading to freckle formation through competition between dendrites.
The properties of rattan cane and its comprehensive utilization technology. Presented by Xinge liu, Shumin Yang, Lili Shang, and Jianfeng Ma, researchers at the International Centre for Bamboo and Rattan. Presented at the ASEAN Rattan Summit.
SCR and TTR modeling using shell and beam elements to deal with local interests, such as touch-down compression or buckling. Two examples are presented. The FEA tool employed is ABAQUS. Videos can only be seen when downloaded.
Werner Kuhn and Hans Kuhn were brilliant 1940s Swiss polymer scientists who developed theories on random coil statistics and entropy of polymer chains. Their work provided a foundation for understanding rubber elasticity. Andrew Keller, a 1950s-1970s Hungarian physical chemist, made important contributions to understanding polymer crystallization through his work on polyethylene single crystals. Pierre de Gennes, a prominent 20th century French physicist, applied his expertise in areas like superconductivity to develop the theory of polymer reptation. Piet Lemstra and Paul Smith were 1980s Dutch polymer scientists who successfully produced high modulus polyethylene through solution processing techniques.
The document discusses numerical simulations of ablation patterns on sublimating materials. It summarizes previous research on crosshatch patterns and experiments by Stock. The approach involves using CFD tools to implement a non-trivial boundary condition for low-temperature ablator camphor. Validation simulations of Baker's experiments on camphor cones show good agreement. Preliminary 3D simulations with turbulent models show localized groove patterns developing from peaks in wall temperature. Future work includes more detailed 3D cases and investigating the wall temperature dependence of groove formation.
Oral presenation AVS 2013 Liwang 10-25-13Liwang Ye
This document summarizes an in situ ATR-FTIR study of TiO2 and HfO2 atomic layer deposition (ALD) on GaAs surfaces. Isotope exchange experiments during TiO2 ALD identified methylmethyleneimine (MMI) as being produced during water exposures and accumulating in the film. Higher temperature ALD of HfO2 at 275°C showed removal of the native GaAs oxide layer, while lower temperature deposition at 200°C did not show significant removal. The study provides insight into surface reactions and film formation mechanisms during high-k dielectric ALD on III-V semiconductor materials.
Wollastonite is a naturally occurring calcium silicate mineral that has potential as a micro-reinforcement in cementitious materials. The presentation evaluated four grades of wollastonite fibers as a partial replacement for cement in mortar and paste mixes. Testing showed that wollastonite improves mechanical properties by reinforcing the brittle matrix at the micro-level. Smaller wollastonite fibers blended more efficiently with the matrix and provided greater improvements in strength and fracture toughness compared to coarser fibers. The addition of wollastonite reduced early-age plastic shrinkage cracking and improved long-term flexural strength, toughness, and compressive strength up to 60%, 140%, and 30% respectively. Hybrid fiber reinforcement
This document discusses using ultrafast lasers to drive plasma for space propulsion applications. Key points include:
- Lasers at the University of Michigan are being used to accelerate protons and deuterons from various target materials for propulsion. Proton beams up to 13 MeV have been observed.
- Target composition, thickness, and surface conditions can affect the maximum proton energy and beam profile. Filamentation in beam profiles resembles simulations of electron behavior.
- Future laser development aims to reach petawatt powers at 30-40 femtosecond pulses for high efficiency ion acceleration. Simulation models describe ion acceleration from laser-driven relativistic electron clouds.
This document discusses plastics and polyethylene (PE) specifically. It notes that while plastics are fantastic due to their diverse uses, low production costs, and material properties, they also have environmental downsides when not disposed of properly. PE has a wide range of microstructures that give it varying properties and uses. It is one of the world's largest commodities, with over 80 million tonnes produced annually for a huge diversity of applications. However, plastic waste in the environment is a current issue that requires better recycling and disposal practices.
This presentation gives a summary of how Polyethylene (PE). can crystallise from solution and the melt. The crystallisation of PE is both remarkable and very beautiful. The way PE crystallises is very important in relation to the properties of PE plastic bags, extrusions and high modulus PE fibres.
Polyethylene polymer crystallisation results in beautiful crystalline microstructures. Polyethylene chains can form chain folded single crystals when crystallized from solution, or "shish kebab" fibrous crystals if shear is applied. When crystallized from the melt, polyethylene typically forms spherulite crystals made up of chain folded lamella that are 1-10 microns in diameter. The crystalline structures that form rival diamond in their beauty and molecular organization despite starting as flexible polymer chains.
This presentation is for my last Cambridge Rheology course lecture. The presentation links course work with research that had been carried out in the Department. The presentation has been modified a little to aid web clarity.
Web- Liquid Crytals and Liquid Crystal Polymers-2015malcolmmackley
The document discusses liquid crystals (LCs) and liquid crystal polymers (LCPs). LCs are formed from small, semi-rigid rod-like molecules that have liquid-like properties but local molecular ordering, giving them useful optical properties. LCPs, discovered in the 1970s, are made from semi-rigid polymer chains and similarly have local anisotropy and birefringence. The document focuses on "disclination" line defects that occur in both LCs and LCPs, influencing their overall orientation. Micrographs show various disclination textures in thermotropic LCPs under different conditions. While LCPs have locally ordered structures, controlling the disclination defect texture across the whole
1) In 1969, Prof. Albert Pennings discovered that Taylor vortices in Couette flow could induce elongated "shish kebab" crystal fibers of polyethylene from solution.
2) Also in 1969, Sir Charles Frank concluded that polyethylene could have a Young's modulus of 210 GPa if the chains were all aligned based on its similarity to diamond's unit cell structure.
3) In the 1970s, Frank and Mackley's experiments using opposed jets showed localized chain extension and "shish kebab" crystal formation, but with low overall modulus.
This presentation was given in 2010 at a British Society of Rheology meeting on Biorheology held at Nottingham University.
The presentation describes the rheology of certain dysphagia formulations and then introduces "The Cambridge Throat". A mechanical device for following the way fluids are drawn into the throat by a model tongue and then how the fluid flows down the back of the throat.
This presentation was given at CEMEF (Mines ParisTech) Sophia Antipolis in 2005. The presentation is concerned with microstructure mechanisms that can explain certain shear thinning behaviour of certain complex fluids.
This presentation was given in Cardiff at the European Society of Rheology Conference in 2009. The presentation is about research in "extreme" areas of rheology and includes work on measuring the viscoelasticity of low viscosity fluids and the limiting extensional viscosity of high viscosity fluids.
Ink jet rheology and processing-Monash 2009malcolmmackley
This presentation gives a summary of work carried out in the Chemical Engineering Department at Cambridge on the rheology and processing of ink jet fluids. The linear viscoelastic properties are captured using a PAV rheometer and the non linear extensional behaviour using a "Cambridge Trimaster".
This document summarizes research on inventing plastic microcapillary films (MCFs) conducted by Malcolm Mackley and others at the University of Cambridge. The researchers developed a novel process to continuously extrude plastic MCFs with controlled voidage levels below 10% using a single-screw extruder, die design, and gas injection. They characterized the MCF structures and capillary sizes. Further mechanical drawing of the MCFs after extrusion was shown to orient the structure while limiting drawability due to necking in the capillaries. This research advanced engineering of plastic MCFs with tailored properties.
This was my last Departmental seminar given in Chemical Engineering at Cambridge. It tells the story of apparatus and process invention. I have included pictures that influenced my career.
The Cambridge Multipass Rheometer (MPR) is capable of performing rheology measurements under varied temperature, pressure, flow, and time conditions. It has four models that can impose temperature from -10 to 210°C, pressure from 1 to 200 bar, flow from 1 to 100,000 reciprocal seconds, and time from milliseconds to hours. The MPR uses enclosed volumes and interchangeable inserts to perform experiments in different flow modes like pressure variation, flow curves, and cross-slot flow. It has been used to study materials like polymers, foods, foams and other complex fluids.
Professor David Moldenhauer is a Fellow of Robinson College and Professor of Process Innovation at the University of Cambridge who has pioneered new methods for shaping chocolate through extrusion and other non-traditional forming techniques by applying his scientific understanding of chocolate's properties and microstructure to invent innovative processing methods.
This document summarizes experimental work validating numerical simulations of precise polymer melt processing using the Cambridge Multipass Rheometer (MPR). [1] The MPR was used to perform slit flow and cross-slot flow experiments on polymer melts like polystyrene. [2] Both the Pom-Pom and Rolie-Poly constitutive models were able to simulate the rheology and match experimental pressure drop and flow patterns when appropriate relaxation spectra and nonlinear parameters were used. [3] The validation demonstrates the ability of numerical simulation to accurately model complex viscoelastic flows.
Leveraging Generative AI to Drive Nonprofit InnovationTechSoup
In this webinar, participants learned how to utilize Generative AI to streamline operations and elevate member engagement. Amazon Web Service experts provided a customer specific use cases and dived into low/no-code tools that are quick and easy to deploy through Amazon Web Service (AWS.)
How to Download & Install Module From the Odoo App Store in Odoo 17Celine George
Custom modules offer the flexibility to extend Odoo's capabilities, address unique requirements, and optimize workflows to align seamlessly with your organization's processes. By leveraging custom modules, businesses can unlock greater efficiency, productivity, and innovation, empowering them to stay competitive in today's dynamic market landscape. In this tutorial, we'll guide you step by step on how to easily download and install modules from the Odoo App Store.
This presentation was provided by Racquel Jemison, Ph.D., Christina MacLaughlin, Ph.D., and Paulomi Majumder. Ph.D., all of the American Chemical Society, for the second session of NISO's 2024 Training Series "DEIA in the Scholarly Landscape." Session Two: 'Expanding Pathways to Publishing Careers,' was held June 13, 2024.
Philippine Edukasyong Pantahanan at Pangkabuhayan (EPP) CurriculumMJDuyan
(𝐓𝐋𝐄 𝟏𝟎𝟎) (𝐋𝐞𝐬𝐬𝐨𝐧 𝟏)-𝐏𝐫𝐞𝐥𝐢𝐦𝐬
𝐃𝐢𝐬𝐜𝐮𝐬𝐬 𝐭𝐡𝐞 𝐄𝐏𝐏 𝐂𝐮𝐫𝐫𝐢𝐜𝐮𝐥𝐮𝐦 𝐢𝐧 𝐭𝐡𝐞 𝐏𝐡𝐢𝐥𝐢𝐩𝐩𝐢𝐧𝐞𝐬:
- Understand the goals and objectives of the Edukasyong Pantahanan at Pangkabuhayan (EPP) curriculum, recognizing its importance in fostering practical life skills and values among students. Students will also be able to identify the key components and subjects covered, such as agriculture, home economics, industrial arts, and information and communication technology.
𝐄𝐱𝐩𝐥𝐚𝐢𝐧 𝐭𝐡𝐞 𝐍𝐚𝐭𝐮𝐫𝐞 𝐚𝐧𝐝 𝐒𝐜𝐨𝐩𝐞 𝐨𝐟 𝐚𝐧 𝐄𝐧𝐭𝐫𝐞𝐩𝐫𝐞𝐧𝐞𝐮𝐫:
-Define entrepreneurship, distinguishing it from general business activities by emphasizing its focus on innovation, risk-taking, and value creation. Students will describe the characteristics and traits of successful entrepreneurs, including their roles and responsibilities, and discuss the broader economic and social impacts of entrepreneurial activities on both local and global scales.
Elevate Your Nonprofit's Online Presence_ A Guide to Effective SEO Strategies...TechSoup
Whether you're new to SEO or looking to refine your existing strategies, this webinar will provide you with actionable insights and practical tips to elevate your nonprofit's online presence.
Temple of Asclepius in Thrace. Excavation resultsKrassimira Luka
The temple and the sanctuary around were dedicated to Asklepios Zmidrenus. This name has been known since 1875 when an inscription dedicated to him was discovered in Rome. The inscription is dated in 227 AD and was left by soldiers originating from the city of Philippopolis (modern Plovdiv).
1. IFM Cambridge
December 2013
Fast Filament Stretching, Thinning and Breakup
By
Malcolm Mackley, Simon Butler, Damien Vadillo,
Tri Tuladhar, Stephen Hoath and Stewart Huxley
Department of Chemical Engineering and Biotechnology
University of Cambridge
Cambridge, CB2 3RA, UK.
1
3. MRM last BSR Presentation
London 2011
“This could be the last time, this could be the last time,
maybe the last time, I don‟t know.”
4. Slow Filament Stretching
On the coefficient of viscous traction and its
relation to that of viscosity
Fred Trouton
Proc. R. Soc. Lond. A 1906
strain rate matrix
0
ii + P = 2 ii
0
0
0
2
0
0
2
The Trouton Ratio
11 + P = 2
22 + P = - 2
11 - 22
e
2
= 3 = e
= 3
4
5. M1 Fluid Extensional viscosity muddle
David James and Ken Walters,
A.A. Collyer (Ed.), Techniques of
Rheological Measurement,
Elsevier,NewYork, 1994, pp. 33–53.
Chris. Petrie
Extensional viscosity: A critical discussion
J. Non-Newtonian Fluid Mech. 137 (2006) 15–23
5
6. Filament thinning
Newtonian modelling
zz P 2
zz
0
rr P 2 rr 2 / D
D
E zz rr 3 2 / D
Mass Balance
D
1
D
2
P
D (t ) D 0
3
t
6
8. Filament thinning
A.V.Bazilevsky, V.M. Entov and A.N.Rozhkov
3rd European Rheology Conference 1990 Ed D.R.Oliver
The “Russian Rheotester”
C
A
zz
B
E
Top plate
15 cm
D
Bottom plate
8
rr
9. Liang and Mackley (1994)
Extensional Rheotester
S1 fluid
PIB solutions
D (t ) D 0
3
t
9
R. Liang and M.R. Mackley. Journal of Non-Newtonian Fluid Mech. 52, 387-405 (1994).
10. Liang and Mackley (1994)- Viscoelastic fluids
S1 fluid
First approximation
1
D ( t ) D 0 exp
3
R
t
Viscoelastic modelling (John Hinch)
PIB solutions
D / D g / 3
g
D(t) D 0 exp
3η t
10
11. Multipass Rheometer (MPR) Filament Stretch Rheometer
The MK1 Cambridge Trimaster
Vp
D
R(z,t)
Top Piston
Rmid(t)
Lf
L0
Bottom Piston
Vp
(a) Test fluid positioned
between two pistons.
(b) Test fluid stretched uniaxially (c) Filament thinning and break up
occurrence after pistons has stopped.
at a uniform velocity.
t0
t<0
Tuladhar, T.R. and Mackley, M.R., Journal of Non-Newtonian Fluid Mechanics, 148 97-108. (2008)
11
12. Lodge Commemorative Meeting on Rheometry
Miskin Manor Cardiff 10 -12th April, 2006
Filament profile just before break up
DEP
DEP + 5.0 wt%
1.2 mm
t = 7 ms
t = 2 ms
13. The MK 2 Cambridge Trimaster
A dream turning into a reality
Toothed belt
timing pulley
Linear guide rail
Carrier
Timing belt
Replaceable top and
bottom plate
Stepper motor
attached to a pulley
13
Graphics courtesy of James Waldmeyer
15. Piston response
5000
10 mm/s
100 mm/s
500 mm/s
4000
Top piston
position (mm) 3000
2000
1000
c
0
0
100
200
300
400
500
600
Time (ms)
15
16. The „TriMaster‟ Filament stretch and break up apparatus
piston
sample
belt
pulley
Initial gap ≈ 0.2 mm, Final gap ≈ 1.2 mm
Piston diameter ≈ 1.2 mm, Piston velocity ≈ 100 mm/s16
18. Filament thinning
DEP
DEP
+ 2.5%
PS110
Piston velocity 0.15 m/s
D.C.Vadillo, T.Tuladhar, A.C. Mulji, S. Jung, S.D. Hoath,and M.R. Mackley
Journal of Rheology 54, 2 .261-282 (2010)
18
19. Mid filament diameter time evolution
1200
0%
0.50%
1%
2.50%
5%
1000
800
D
(mm )
600
400
200
0
0
10
20
30
40
Time ( ms )
19
24. Trimaster development: the HB4
Overhead view of the instrument
Camera
Close up of the pistons
Drive wheel
Top
piston
Bottom
piston
Arms holding Light source
the pistons
30. Sorting out the good from the bad
Commercial ceramic good and bad inks
Filament diameter,D, (µm )
500
After stretching
450
400
30A-Ink A1-Ceramic Sinker-Good jetting-18K
31A-Ink A2-Ceramic Yellow-Bad jetting-18K
350
300
250
200
150
100
50
0
0.0
1.0
2.0
3.0
4.0
5.0
Time, t, (ms)
“Good ink”
“Bad ink”
30
32. Conclusions
HB4 Cambridge Trimaster
Can follow fast filament stretch thinning and breakup
process of low viscosity fluids.
There is a link between ink jet processing and HB4 data.
(See Steve Hoath presentation)
Acknowledgments
EPSRC and industrial partners in
Next Generation Ink Jet Consortium
32