This study examines how different treatments of the Kelvin effect in simulations of young aircraft contrails can impact results. The Kelvin effect, which depends on particle size, influences vapor saturation pressure over ice particles. Neglecting or lowering the Kelvin effect is found to substantially alter the evolution of the ice particle size distribution and delay the onset of particle loss. Simulation results show that particle survival rates, mean size, and optical depth can vary by up to factors of 4 to 50% depending on how the Kelvin effect is modeled. The exponential relationship between particle survival rate and size is strongly dependent on the Kelvin effect for high soot emissions.
This document introduces a reduced order ODE model to predict the evolution of contrails formed by aircraft. The model aims to capture the key physical processes in the jet, induction, vortex, and dispersion phases of contrail formation using only 4 non-dimensional groupings, achieving a significant reduction in complexity compared to full simulations. Large eddy simulations are used to infer trends in wake size, particle growth and survival that the ODE model will represent. The model equations describe the bulk conservation of mass and momentum in the contrail wake as it descends through the stratified atmosphere, undergoing compression. Microphysical processes involving particle growth are also modeled.
Advances in Rock Physics Modelling and Improved Estimation of CO2 Saturation, Giorgos Papageorgiou - Geophysical Modelling for CO2 Storage, Leeds, 3 November 2015
The International Journal of Engineering & Science is aimed at providing a platform for researchers, engineers, scientists, or educators to publish their original research results, to exchange new ideas, to disseminate information in innovative designs, engineering experiences and technological skills. It is also the Journal's objective to promote engineering and technology education. All papers submitted to the Journal will be blind peer-reviewed. Only original articles will be published.
The papers for publication in The International Journal of Engineering& Science are selected through rigorous peer reviews to ensure originality, timeliness, relevance, and readability.
This document summarizes a case study that used geophysical methods to characterize focused seepage through an earthfill dam. Resistivity and self-potential tomography were used to investigate anomalous seepage. The self-potential signals provide information about groundwater flow patterns because the source current density responsible for the SP signals is proportional to the Darcy velocity. However, the resistivity distribution also influences the SP distribution, so resistivity and SP data need to be used together. The study conducted resistivity and SP surveys at a dam in Colorado experiencing anomalous seepage at the toe. The data revealed SP and resistivity anomalies that were used to delineate three anomalous seepage zones and estimate the source of localized seepage
1. The document defines key rock physics terms including density, porosity, saturation, velocity, impedance, Poisson's ratio, and reflection coefficients. Equations are provided for calculating these values from measured properties.
2. Methods of modeling reflection seismograms are described including normal reflection, reflection at an angle using Zoeppritz equations, AVO analysis, and impedance inversion.
3. Concepts of stress, strain, elasticity, elastic moduli, and their relationships to velocity are covered. The differences between static and dynamic moduli are also discussed.
This document summarizes interferometric synthetic aperture radar (InSAR) measurements of ground deformation at the Krafla and Bjarnarflag geothermal areas in Iceland between 1993-2015. The InSAR data shows subsidence rates have been relatively steady over this period. Modeling indicates subsurface deflation sources located 0.9-1.5 km deep can explain the observed deformation, with a volume decrease of less than 105 m3/yr. A model using a source for each borehole provides a slightly better fit than a single source for each area. The deformation is likely caused by pressure drops and thermal contraction from ongoing geothermal fluid extraction, with some fluid renewal occurring.
This document provides an overview of rock physics concepts for quantitative seismic interpretation. It discusses the importance of incorporating rock physics principles into seismic analysis to correctly interpret seismic data. A key pitfall is using inappropriate velocity-porosity relations that do not account for sedimentological variations. The document emphasizes that the appropriate velocity-porosity relation depends on the geological model and rock physics analysis of well logs and cores. It also introduces the concept of elastic bounds, which provide a framework for velocity-porosity relations when only volume fractions and moduli are known.
This document summarizes a study on using electrical conductivity measurements to quantify the smectite and chlorite content in rock cores from Krafla, Iceland. The study finds that electrical conductivity, when normalized by formation factor and porosity, correlates strongly with smectite content as determined by cation exchange capacity measurements. Smectite has weaker molecular bondings than chlorite, allowing it to contribute more to electrical conductivity. Between 7-20% clay content corresponds to 5-18% chlorite in whole rock samples. The ability to measure smectite content electrically could help locate transitions between hydrothermal heat convection and conduction zones.
This document introduces a reduced order ODE model to predict the evolution of contrails formed by aircraft. The model aims to capture the key physical processes in the jet, induction, vortex, and dispersion phases of contrail formation using only 4 non-dimensional groupings, achieving a significant reduction in complexity compared to full simulations. Large eddy simulations are used to infer trends in wake size, particle growth and survival that the ODE model will represent. The model equations describe the bulk conservation of mass and momentum in the contrail wake as it descends through the stratified atmosphere, undergoing compression. Microphysical processes involving particle growth are also modeled.
Advances in Rock Physics Modelling and Improved Estimation of CO2 Saturation, Giorgos Papageorgiou - Geophysical Modelling for CO2 Storage, Leeds, 3 November 2015
The International Journal of Engineering & Science is aimed at providing a platform for researchers, engineers, scientists, or educators to publish their original research results, to exchange new ideas, to disseminate information in innovative designs, engineering experiences and technological skills. It is also the Journal's objective to promote engineering and technology education. All papers submitted to the Journal will be blind peer-reviewed. Only original articles will be published.
The papers for publication in The International Journal of Engineering& Science are selected through rigorous peer reviews to ensure originality, timeliness, relevance, and readability.
This document summarizes a case study that used geophysical methods to characterize focused seepage through an earthfill dam. Resistivity and self-potential tomography were used to investigate anomalous seepage. The self-potential signals provide information about groundwater flow patterns because the source current density responsible for the SP signals is proportional to the Darcy velocity. However, the resistivity distribution also influences the SP distribution, so resistivity and SP data need to be used together. The study conducted resistivity and SP surveys at a dam in Colorado experiencing anomalous seepage at the toe. The data revealed SP and resistivity anomalies that were used to delineate three anomalous seepage zones and estimate the source of localized seepage
1. The document defines key rock physics terms including density, porosity, saturation, velocity, impedance, Poisson's ratio, and reflection coefficients. Equations are provided for calculating these values from measured properties.
2. Methods of modeling reflection seismograms are described including normal reflection, reflection at an angle using Zoeppritz equations, AVO analysis, and impedance inversion.
3. Concepts of stress, strain, elasticity, elastic moduli, and their relationships to velocity are covered. The differences between static and dynamic moduli are also discussed.
This document summarizes interferometric synthetic aperture radar (InSAR) measurements of ground deformation at the Krafla and Bjarnarflag geothermal areas in Iceland between 1993-2015. The InSAR data shows subsidence rates have been relatively steady over this period. Modeling indicates subsurface deflation sources located 0.9-1.5 km deep can explain the observed deformation, with a volume decrease of less than 105 m3/yr. A model using a source for each borehole provides a slightly better fit than a single source for each area. The deformation is likely caused by pressure drops and thermal contraction from ongoing geothermal fluid extraction, with some fluid renewal occurring.
This document provides an overview of rock physics concepts for quantitative seismic interpretation. It discusses the importance of incorporating rock physics principles into seismic analysis to correctly interpret seismic data. A key pitfall is using inappropriate velocity-porosity relations that do not account for sedimentological variations. The document emphasizes that the appropriate velocity-porosity relation depends on the geological model and rock physics analysis of well logs and cores. It also introduces the concept of elastic bounds, which provide a framework for velocity-porosity relations when only volume fractions and moduli are known.
This document summarizes a study on using electrical conductivity measurements to quantify the smectite and chlorite content in rock cores from Krafla, Iceland. The study finds that electrical conductivity, when normalized by formation factor and porosity, correlates strongly with smectite content as determined by cation exchange capacity measurements. Smectite has weaker molecular bondings than chlorite, allowing it to contribute more to electrical conductivity. Between 7-20% clay content corresponds to 5-18% chlorite in whole rock samples. The ability to measure smectite content electrically could help locate transitions between hydrothermal heat convection and conduction zones.
This document discusses the combined effects of pressure and cementation on 4D seismic data from a reservoir in offshore Australia. It summarizes previous work that used an elastic model to predict the 4D seismic response from pore pressure changes during water injection, but found the actual observed anomalies were larger than predicted. A new non-elastic model is developed that accounts for changes in grain cement during pressure changes. Application of this model to a water injector found significant mechanical weakening of the reservoir rock was needed to explain the large observed 4D signals, suggesting a decrease in effective grain cement during injection. This non-elastic approach may enable more accurate 4D interpretations.
Time-elApSe heTerogeneiTy meASuremenT in Two SedimenTAry roCkS: impliCATionS ...Ali Osman Öncel
This document summarizes an experiment that measured time-lapse changes in seismic velocity in two sedimentary rock samples with different porosities. The experiment saturated the rock samples with water and oil over time and used an LDV system to monitor changes in ultrasonic seismic velocity. Results showed that seismic velocity decreased with increasing water saturation but increased with oil saturation. Higher porosity rocks showed faster saturation rates and larger seismic velocity changes compared to lower porosity rocks. The study demonstrated that monitoring time-lapse seismic velocity changes can provide insights into how rock properties vary with changing fluid saturation levels.
2005 emerging insights into the dynamics of submarine debris flowsshh315
This document summarizes recent research on the dynamics of submarine debris flows. Key points include:
1) Hydroplaning, where the flow rides on a cushion of water, allows debris flows to travel much farther than expected and may help explain long runout distances.
2) Intruding water may soften stiff clay material in the neck of the flow, facilitating separation of the head block and further accelerating the flow.
3) Laboratory experiments using materials from clay-rich to sandy revealed a transition between low-suspension plug flows to more agitated flows that generate turbidity currents.
4) Statistical analysis of a large submarine landslide found scaling behaviors that models have difficulty reproducing,
1. The document proposes a new method to localize preferential fluid flow pathways in porous media using time-lapse self-potential measurements during a saline tracer test.
2. A laboratory sandbox experiment demonstrated the ability to track the velocity of a saline pulse through a coarse-sand channel using electrical potential sensors on the surface.
3. Numerical modeling was able to reproduce the electrical potential distribution observed over the channel but had some discrepancies on the banks. The method shows promise for field applications to detect leaking areas in earth structures like dams.
1) The document summarizes laboratory experiments conducted to evaluate the effects of multiple fractures on the permeability and porosity of basaltic rocks from the Krafla geothermal reservoir in Iceland.
2) The results show that generating the first macro-fracture through Brazilian tensile testing induced the most significant increases in permeability and porosity.
3) Generating a second fracture imparted little additional effect on permeability across the range of rock porosities tested. Permeability and porosity generally decreased with increasing effective pressure.
Molecular water detected on the sunlit Moon by SOFIASérgio Sacani
Widespread hydration was detected on the lunar surface
through observations of a characteristic absorption feature
at 3 µm by three independent spacecraft1–3
. Whether the
hydration is molecular water (H2O) or other hydroxyl (OH)
compounds is unknown and there are no established methods to distinguish the two using the 3 µm band4. However, a
fundamental vibration of molecular water produces a spectral
signature at 6 µm that is not shared by other hydroxyl compounds5
. Here, we present observations of the Moon at 6 µm
using the NASA/DLR Stratospheric Observatory for Infrared
Astronomy (SOFIA). Observations reveal a 6 µm emission
feature at high lunar latitudes due to the presence of molecular water on the lunar surface. On the basis of the strength
of the 6 µm band, we estimate abundances of about 100 to
400 µg g−1
H2O. We find that the distribution of water over the
small latitude range is a result of local geology and is probably
not a global phenomenon. Lastly, we suggest that a majority of
the water we detect must be stored within glasses or in voids
between grains sheltered from the harsh lunar environment,
allowing the water to remain on the lunar surface.
Oil and gas reserves sensitivity to log evaluationPeter Cockcroft
A paper by Peter Cockcroft and John Owens about sensitivity of log analysis to oil and gas reserves estimations. Presented to to the Society of Core Analysts in 1990 by John Owens
The document discusses analytical ultracentrifugation techniques invented by Theodor Svedberg in 1923 for which he won the Nobel Prize in Chemistry in 1926. It can accelerate samples up to 1,000,000 g and is used to determine sedimentation velocity and equilibrium of proteins and other molecules. The Svedberg equation calculates the sedimentation velocity of spherical proteins based on properties like molecular weight, partial specific volume, and temperature in water. Comparisons to calculated values can provide insights into a protein's quaternary structure and shape. Sedimentation equilibrium also characterizes membrane proteins and can determine molar mass while accounting for any bound detergent. Solution NMR methods like spin relaxation and multidimensional NMR are also discussed.
A New Approximation of Water Saturation Estimation Based on Vertical Seismic ...IJERA Editor
1) The document presents a new method for estimating water saturation values based on analyzing seismic wave attenuation using the Biot-Turgut-Yamamoto-Sismanto equation.
2) The method is applied to vertical seismic profiling (VSP) data from the Pasir Cantang well in West Java to estimate water saturation values for some layers.
3) While the method can technically estimate water saturation from VSP data, the results have not been calibrated against known well values, which is an important step for accuracy.
Pore scale dynamics and the interpretation of flow processes - Martin Blunt, Imperial College London, at UKCCSRC specialist meeting Flow and Transport for CO2 Storage, 29-30 October 2015
This document outlines a study that used direct shear box testing to examine the potential for seismic and aseismic slip in Svalbard shale. The background discusses the geological context and in situ stresses. A direct shear box rig was used to test pre-fractured shale specimens under varying shear velocities. The results showed that the shale's friction coefficient increased with velocity, implying non-seismic slip could occur on bedding-parallel fractures. Mineralogical analysis also supported potential for aseismicity. In conclusion, the direct shear tests provided insight into seismic/aseismic hazard risk by showing the Svalbard shale may slip aseismically at the test interval, consistent with no recorded microseismicity during a nearby injection test
This document discusses factors that influence seismic velocity in rock formations. It provides tables of typical P-wave and S-wave velocities for different rock types, showing variations with properties like porosity, fluid saturation, and effective pressure. Graphs demonstrate how velocities generally increase with effective pressure and can vary with pore fluid, increasing or decreasing depending on the rock's elastic properties. The amount of velocity change with pressure and saturation indicates the quantity of soft, crack-like pore space within the rock. Overall, the document examines how porosity, pore fluids, effective pressure, and crack density impact seismic velocities through their effects on the rock's elastic modulus and density.
This document describes an extension of the SRICOS method for predicting scour depth at bridge piers. The extended method, called E-SRICOS, accounts for variable flow velocities over time (velocity-time histories) and multilayer soil stratigraphy. It accumulates the effects of different velocities and sequences through soil layers to predict scour depth. The document outlines the E-SRICOS algorithms and procedures. It also presents a simplified version, S-SRICOS, and compares predictions of both methods to measurements at eight bridge sites in Texas.
This document discusses basic geophysical concepts including:
1) The relationships between various rock physics properties such as density, bulk modulus, shear modulus, Young's modulus, Poisson's ratio, P-wave modulus, and velocities.
2) Factors that influence seismic reflection coefficients such as contrasts in lithology, porosity, saturation, and diagenesis due to their impact on acoustic impedance.
3) Amplitude Variation with Offset (AVO) analysis and the Aki-Richards approximation for P-wave reflectivity as a function of incident angle based on changes in P-wave velocity, S-wave velocity, and density.
Evidence for plumes of water on Europa has previously been found using the Hubble Space Telescope using two
different observing techniques. Roth et al. found line emission from the dissociation products of water. Sparks et al.
found evidence for off-limb continuum absorption as Europa transited Jupiter. Here, we present a new transit
observation of Europa that shows a second event at the same location as a previous plume candidate from Sparks
et al., raising the possibility of a consistently active source of erupting material on Europa. This conclusion is
bolstered by comparison with a nighttime thermal image from the Galileo Photopolarimeter-Radiometer that shows
a thermal anomaly at the same location, within the uncertainties. The anomaly has the highest observed brightness
temperature on the Europa nightside. If heat flow from a subsurface liquid water reservoir causes the thermal
anomaly, its depth is ≈1.8–2 km, under simple modeling assumptions, consistent with scenarios in which a liquid
water reservoir has formed within a thick ice shell. Models that favor thin regions within the ice shell that connect
directly to the ocean, however, cannot be excluded, nor modifications to surface thermal inertia by subsurface
activity. Alternatively, vapor deposition surrounding an active vent could increase the thermal inertia of the surface
and cause the thermal anomaly. This candidate plume region may offer a promising location for an initial
characterization of Europa’s internal water and ice and for seeking evidence of Europa’s habitability.
Passive seismic monitoring for CO2 storage sites - Anna Stork, University of Bristol at UKCCSRC specialist meeting Geophysical modelling for CO2 storage, monitoring and appraisal, 3 November 2015
Investigation of Supercavitation PhysicsSiyao Shao
1. The document summarizes an investigation into supercavitation physics conducted in two laboratories. It included studies of ventilated cavitation, configuration effects, and a comparison of ventilated and natural supercavitation.
2. Key findings included that results from the two laboratories for ventilated cavitation agreed well, and that a backward facing model provided better visualization of natural supercavitation compared to a forward facing model.
3. The formation and evolution of natural supercavitation was observed, including four stages of cavity development. Choking behavior, where cavity size remains constant despite pressure changes, was demonstrated and used to measure minimum cavitation numbers.
This document summarizes a preliminary study of natural supercavitation conducted in a water tunnel. Experiments were performed using backward and forward facing models of different diameters. Key findings include: natural supercavities evolved rapidly from bubbly flows to stable shapes; choking occurred when further pressure reduction did not change cavity size; cavity closure types changed from twin vortices to quad vortices to re-entrant jets with increasing flow speed; and natural supercavity sizes agreed reasonably well with theoretical models. Future work may involve different model shapes, developing stable forward facing models, improved cavity dimension metrics, and temperature measurements.
This document discusses resistivity logs and how they are used to analyze borehole formations. Resistivity is measured in ohms per meter and depends on factors like water volume, temperature, and salinity. Resistivity logs can determine hydrocarbon versus water-bearing zones and indicate permeable zones. The Archie equation relates resistivity to water saturation and uses constants determined by rock type. Different resistivity tools like electrode and induction logs measure resistivity at varying depths around the borehole to analyze fluid content and identify zones.
1) The document discusses methods for calculating water saturation (SW) and formation water resistivity (RW) using well log data and interactive petrophysics programs.
2) It describes various models and techniques for determining SW, such as Archie's equation, Rwa approach, crossplots, and other empirical models. It also discusses six ways to calculate RW, including from Archie's equation, resistivity-porosity crossplots, and direct water sampling.
3) The results section calculates SW using different well log measurements and models, and determines RW from temperature and resistivity crossplots. It concludes by discussing factors that affect the accuracy of SW and RW calculations.
Mat completo dir. adm carreiras jurídicas 2015Fabiano Gabriel
O documento discute os principais princípios do Direito Administrativo brasileiro, como legalidade, impessoalidade, moralidade, publicidade e eficiência. Também apresenta outros princípios como finalidade pública, presunção de legitimidade, autotutela, motivação e proporcionalidade. Por fim, aborda a questão da greve no serviço público e a suspensão do pagamento durante os dias de paralisação.
Plataformas de Redes Sociales en la Web
Definición
Una red social es una estructura social formada por personas o entidades conectadas y unidas entre sí por algún tipo de relación o interés común.
Características de las redes sociales
Área de Participación Ciudadana. Medio de comunicación cada vez más utilizado en detrimento del correo electrónico.
Comunidad o punto de encuentro en el que los usuarios construyen, comparten y desarrollan conocimientos.
Se puede hacer uso de Sindicación de Contenidos (RSS), proporcionando notificaciones automáticas de nuevos contenidos.
Suscripciones a eventos, noticias y boletines.
Zona personal, para acceder a servicios personalizados.
Apartado de Encuestas / Votaciones para participar.
Fácil acceso a las mismas a través del ordenador, móviles, PDA, TDT, etc.
Tienen un papel facilitador para el logro de resultados.
Ventajas
Reencuentro con conocidos.
Oportunidad de integrarse a reuniones breves vía online con fines lúdicos y de entretenimiento con el propósito de movilizar a miles de personas.
Excelentes para propiciar contactos afectivos nuevos.
Compartir momentos especiales con las personas cercanas a nuestras vidas.
Sirven para conectar gente sin importar la distancia.
Perfectas para establecer conexiones con el mundo profesional.
Tener información actualizada acerca de temas de interés, además permiten acudir a eventos, participar en actos y conferencias.
La comunicación puede ser en tiempo real.
Pueden generar movimientos masivos de solidaridad ante una situación de crisis.
Bastantes dinámicas para producir contenido en Internet.
Desventajas
Son peligrosas si no se configura la privacidad correctamente, pues exponen nuestra vida privada.
Pueden darse casos de suplantación de personalidad.
Falta en el control de datos.
Pueden ser adictivas y devorar gran cantidad de nuestro tiempo, pues son ideales para el ocio.
Pueden apoderarse de todos los contenidos que publicamos.
Pueden ser utilizadas por criminales para conocer datos de sus víctimas en delitos: como el acoso y abuso sexual, secuestro, tráfico de personas, etc.
Componentes o partes de una red Social
Una red social se clasifica en varias partes entre estas podemos encontrar: el chat, mensajería de correo electrónico, grupos de discusión, videoconferencia, en fin podemos encontrar un amplio menú de cosas que podemos ver, compartir, comentar.
Facebook
Es una herramienta social que conecta a la gente con sus amigos y otras personas que trabajan, estudian y viven en su entorno.
Instagram
Es una red social, programa o aplicación para compartir fotos con la que los usuarios pueden aplicar efectos fotográficos como filtros, marcos, colores retro, luego pueden compartir las fotografías en diferentes redes sociales como Facebook y Twitter.
Twitter
Es un término inglés que puede traducirse como “gorjear” o “trinar”, es el nombre de una red de microblogging que
This document discusses the combined effects of pressure and cementation on 4D seismic data from a reservoir in offshore Australia. It summarizes previous work that used an elastic model to predict the 4D seismic response from pore pressure changes during water injection, but found the actual observed anomalies were larger than predicted. A new non-elastic model is developed that accounts for changes in grain cement during pressure changes. Application of this model to a water injector found significant mechanical weakening of the reservoir rock was needed to explain the large observed 4D signals, suggesting a decrease in effective grain cement during injection. This non-elastic approach may enable more accurate 4D interpretations.
Time-elApSe heTerogeneiTy meASuremenT in Two SedimenTAry roCkS: impliCATionS ...Ali Osman Öncel
This document summarizes an experiment that measured time-lapse changes in seismic velocity in two sedimentary rock samples with different porosities. The experiment saturated the rock samples with water and oil over time and used an LDV system to monitor changes in ultrasonic seismic velocity. Results showed that seismic velocity decreased with increasing water saturation but increased with oil saturation. Higher porosity rocks showed faster saturation rates and larger seismic velocity changes compared to lower porosity rocks. The study demonstrated that monitoring time-lapse seismic velocity changes can provide insights into how rock properties vary with changing fluid saturation levels.
2005 emerging insights into the dynamics of submarine debris flowsshh315
This document summarizes recent research on the dynamics of submarine debris flows. Key points include:
1) Hydroplaning, where the flow rides on a cushion of water, allows debris flows to travel much farther than expected and may help explain long runout distances.
2) Intruding water may soften stiff clay material in the neck of the flow, facilitating separation of the head block and further accelerating the flow.
3) Laboratory experiments using materials from clay-rich to sandy revealed a transition between low-suspension plug flows to more agitated flows that generate turbidity currents.
4) Statistical analysis of a large submarine landslide found scaling behaviors that models have difficulty reproducing,
1. The document proposes a new method to localize preferential fluid flow pathways in porous media using time-lapse self-potential measurements during a saline tracer test.
2. A laboratory sandbox experiment demonstrated the ability to track the velocity of a saline pulse through a coarse-sand channel using electrical potential sensors on the surface.
3. Numerical modeling was able to reproduce the electrical potential distribution observed over the channel but had some discrepancies on the banks. The method shows promise for field applications to detect leaking areas in earth structures like dams.
1) The document summarizes laboratory experiments conducted to evaluate the effects of multiple fractures on the permeability and porosity of basaltic rocks from the Krafla geothermal reservoir in Iceland.
2) The results show that generating the first macro-fracture through Brazilian tensile testing induced the most significant increases in permeability and porosity.
3) Generating a second fracture imparted little additional effect on permeability across the range of rock porosities tested. Permeability and porosity generally decreased with increasing effective pressure.
Molecular water detected on the sunlit Moon by SOFIASérgio Sacani
Widespread hydration was detected on the lunar surface
through observations of a characteristic absorption feature
at 3 µm by three independent spacecraft1–3
. Whether the
hydration is molecular water (H2O) or other hydroxyl (OH)
compounds is unknown and there are no established methods to distinguish the two using the 3 µm band4. However, a
fundamental vibration of molecular water produces a spectral
signature at 6 µm that is not shared by other hydroxyl compounds5
. Here, we present observations of the Moon at 6 µm
using the NASA/DLR Stratospheric Observatory for Infrared
Astronomy (SOFIA). Observations reveal a 6 µm emission
feature at high lunar latitudes due to the presence of molecular water on the lunar surface. On the basis of the strength
of the 6 µm band, we estimate abundances of about 100 to
400 µg g−1
H2O. We find that the distribution of water over the
small latitude range is a result of local geology and is probably
not a global phenomenon. Lastly, we suggest that a majority of
the water we detect must be stored within glasses or in voids
between grains sheltered from the harsh lunar environment,
allowing the water to remain on the lunar surface.
Oil and gas reserves sensitivity to log evaluationPeter Cockcroft
A paper by Peter Cockcroft and John Owens about sensitivity of log analysis to oil and gas reserves estimations. Presented to to the Society of Core Analysts in 1990 by John Owens
The document discusses analytical ultracentrifugation techniques invented by Theodor Svedberg in 1923 for which he won the Nobel Prize in Chemistry in 1926. It can accelerate samples up to 1,000,000 g and is used to determine sedimentation velocity and equilibrium of proteins and other molecules. The Svedberg equation calculates the sedimentation velocity of spherical proteins based on properties like molecular weight, partial specific volume, and temperature in water. Comparisons to calculated values can provide insights into a protein's quaternary structure and shape. Sedimentation equilibrium also characterizes membrane proteins and can determine molar mass while accounting for any bound detergent. Solution NMR methods like spin relaxation and multidimensional NMR are also discussed.
A New Approximation of Water Saturation Estimation Based on Vertical Seismic ...IJERA Editor
1) The document presents a new method for estimating water saturation values based on analyzing seismic wave attenuation using the Biot-Turgut-Yamamoto-Sismanto equation.
2) The method is applied to vertical seismic profiling (VSP) data from the Pasir Cantang well in West Java to estimate water saturation values for some layers.
3) While the method can technically estimate water saturation from VSP data, the results have not been calibrated against known well values, which is an important step for accuracy.
Pore scale dynamics and the interpretation of flow processes - Martin Blunt, Imperial College London, at UKCCSRC specialist meeting Flow and Transport for CO2 Storage, 29-30 October 2015
This document outlines a study that used direct shear box testing to examine the potential for seismic and aseismic slip in Svalbard shale. The background discusses the geological context and in situ stresses. A direct shear box rig was used to test pre-fractured shale specimens under varying shear velocities. The results showed that the shale's friction coefficient increased with velocity, implying non-seismic slip could occur on bedding-parallel fractures. Mineralogical analysis also supported potential for aseismicity. In conclusion, the direct shear tests provided insight into seismic/aseismic hazard risk by showing the Svalbard shale may slip aseismically at the test interval, consistent with no recorded microseismicity during a nearby injection test
This document discusses factors that influence seismic velocity in rock formations. It provides tables of typical P-wave and S-wave velocities for different rock types, showing variations with properties like porosity, fluid saturation, and effective pressure. Graphs demonstrate how velocities generally increase with effective pressure and can vary with pore fluid, increasing or decreasing depending on the rock's elastic properties. The amount of velocity change with pressure and saturation indicates the quantity of soft, crack-like pore space within the rock. Overall, the document examines how porosity, pore fluids, effective pressure, and crack density impact seismic velocities through their effects on the rock's elastic modulus and density.
This document describes an extension of the SRICOS method for predicting scour depth at bridge piers. The extended method, called E-SRICOS, accounts for variable flow velocities over time (velocity-time histories) and multilayer soil stratigraphy. It accumulates the effects of different velocities and sequences through soil layers to predict scour depth. The document outlines the E-SRICOS algorithms and procedures. It also presents a simplified version, S-SRICOS, and compares predictions of both methods to measurements at eight bridge sites in Texas.
This document discusses basic geophysical concepts including:
1) The relationships between various rock physics properties such as density, bulk modulus, shear modulus, Young's modulus, Poisson's ratio, P-wave modulus, and velocities.
2) Factors that influence seismic reflection coefficients such as contrasts in lithology, porosity, saturation, and diagenesis due to their impact on acoustic impedance.
3) Amplitude Variation with Offset (AVO) analysis and the Aki-Richards approximation for P-wave reflectivity as a function of incident angle based on changes in P-wave velocity, S-wave velocity, and density.
Evidence for plumes of water on Europa has previously been found using the Hubble Space Telescope using two
different observing techniques. Roth et al. found line emission from the dissociation products of water. Sparks et al.
found evidence for off-limb continuum absorption as Europa transited Jupiter. Here, we present a new transit
observation of Europa that shows a second event at the same location as a previous plume candidate from Sparks
et al., raising the possibility of a consistently active source of erupting material on Europa. This conclusion is
bolstered by comparison with a nighttime thermal image from the Galileo Photopolarimeter-Radiometer that shows
a thermal anomaly at the same location, within the uncertainties. The anomaly has the highest observed brightness
temperature on the Europa nightside. If heat flow from a subsurface liquid water reservoir causes the thermal
anomaly, its depth is ≈1.8–2 km, under simple modeling assumptions, consistent with scenarios in which a liquid
water reservoir has formed within a thick ice shell. Models that favor thin regions within the ice shell that connect
directly to the ocean, however, cannot be excluded, nor modifications to surface thermal inertia by subsurface
activity. Alternatively, vapor deposition surrounding an active vent could increase the thermal inertia of the surface
and cause the thermal anomaly. This candidate plume region may offer a promising location for an initial
characterization of Europa’s internal water and ice and for seeking evidence of Europa’s habitability.
Passive seismic monitoring for CO2 storage sites - Anna Stork, University of Bristol at UKCCSRC specialist meeting Geophysical modelling for CO2 storage, monitoring and appraisal, 3 November 2015
Investigation of Supercavitation PhysicsSiyao Shao
1. The document summarizes an investigation into supercavitation physics conducted in two laboratories. It included studies of ventilated cavitation, configuration effects, and a comparison of ventilated and natural supercavitation.
2. Key findings included that results from the two laboratories for ventilated cavitation agreed well, and that a backward facing model provided better visualization of natural supercavitation compared to a forward facing model.
3. The formation and evolution of natural supercavitation was observed, including four stages of cavity development. Choking behavior, where cavity size remains constant despite pressure changes, was demonstrated and used to measure minimum cavitation numbers.
This document summarizes a preliminary study of natural supercavitation conducted in a water tunnel. Experiments were performed using backward and forward facing models of different diameters. Key findings include: natural supercavities evolved rapidly from bubbly flows to stable shapes; choking occurred when further pressure reduction did not change cavity size; cavity closure types changed from twin vortices to quad vortices to re-entrant jets with increasing flow speed; and natural supercavity sizes agreed reasonably well with theoretical models. Future work may involve different model shapes, developing stable forward facing models, improved cavity dimension metrics, and temperature measurements.
This document discusses resistivity logs and how they are used to analyze borehole formations. Resistivity is measured in ohms per meter and depends on factors like water volume, temperature, and salinity. Resistivity logs can determine hydrocarbon versus water-bearing zones and indicate permeable zones. The Archie equation relates resistivity to water saturation and uses constants determined by rock type. Different resistivity tools like electrode and induction logs measure resistivity at varying depths around the borehole to analyze fluid content and identify zones.
1) The document discusses methods for calculating water saturation (SW) and formation water resistivity (RW) using well log data and interactive petrophysics programs.
2) It describes various models and techniques for determining SW, such as Archie's equation, Rwa approach, crossplots, and other empirical models. It also discusses six ways to calculate RW, including from Archie's equation, resistivity-porosity crossplots, and direct water sampling.
3) The results section calculates SW using different well log measurements and models, and determines RW from temperature and resistivity crossplots. It concludes by discussing factors that affect the accuracy of SW and RW calculations.
Mat completo dir. adm carreiras jurídicas 2015Fabiano Gabriel
O documento discute os principais princípios do Direito Administrativo brasileiro, como legalidade, impessoalidade, moralidade, publicidade e eficiência. Também apresenta outros princípios como finalidade pública, presunção de legitimidade, autotutela, motivação e proporcionalidade. Por fim, aborda a questão da greve no serviço público e a suspensão do pagamento durante os dias de paralisação.
Plataformas de Redes Sociales en la Web
Definición
Una red social es una estructura social formada por personas o entidades conectadas y unidas entre sí por algún tipo de relación o interés común.
Características de las redes sociales
Área de Participación Ciudadana. Medio de comunicación cada vez más utilizado en detrimento del correo electrónico.
Comunidad o punto de encuentro en el que los usuarios construyen, comparten y desarrollan conocimientos.
Se puede hacer uso de Sindicación de Contenidos (RSS), proporcionando notificaciones automáticas de nuevos contenidos.
Suscripciones a eventos, noticias y boletines.
Zona personal, para acceder a servicios personalizados.
Apartado de Encuestas / Votaciones para participar.
Fácil acceso a las mismas a través del ordenador, móviles, PDA, TDT, etc.
Tienen un papel facilitador para el logro de resultados.
Ventajas
Reencuentro con conocidos.
Oportunidad de integrarse a reuniones breves vía online con fines lúdicos y de entretenimiento con el propósito de movilizar a miles de personas.
Excelentes para propiciar contactos afectivos nuevos.
Compartir momentos especiales con las personas cercanas a nuestras vidas.
Sirven para conectar gente sin importar la distancia.
Perfectas para establecer conexiones con el mundo profesional.
Tener información actualizada acerca de temas de interés, además permiten acudir a eventos, participar en actos y conferencias.
La comunicación puede ser en tiempo real.
Pueden generar movimientos masivos de solidaridad ante una situación de crisis.
Bastantes dinámicas para producir contenido en Internet.
Desventajas
Son peligrosas si no se configura la privacidad correctamente, pues exponen nuestra vida privada.
Pueden darse casos de suplantación de personalidad.
Falta en el control de datos.
Pueden ser adictivas y devorar gran cantidad de nuestro tiempo, pues son ideales para el ocio.
Pueden apoderarse de todos los contenidos que publicamos.
Pueden ser utilizadas por criminales para conocer datos de sus víctimas en delitos: como el acoso y abuso sexual, secuestro, tráfico de personas, etc.
Componentes o partes de una red Social
Una red social se clasifica en varias partes entre estas podemos encontrar: el chat, mensajería de correo electrónico, grupos de discusión, videoconferencia, en fin podemos encontrar un amplio menú de cosas que podemos ver, compartir, comentar.
Facebook
Es una herramienta social que conecta a la gente con sus amigos y otras personas que trabajan, estudian y viven en su entorno.
Instagram
Es una red social, programa o aplicación para compartir fotos con la que los usuarios pueden aplicar efectos fotográficos como filtros, marcos, colores retro, luego pueden compartir las fotografías en diferentes redes sociales como Facebook y Twitter.
Twitter
Es un término inglés que puede traducirse como “gorjear” o “trinar”, es el nombre de una red de microblogging que
Este trabajo se ha diseñado con el objetivo de ampliar, los conocimientos que se tienen con respecto a la administración y sus enfoques.
Tener amplio claridad en el manejo empresarial y sus alcances.
Los números naturales incluyen los enteros positivos y se usan para contar objetos. Los números enteros incluyen además del cero y los números naturales, los números negativos. Los números racionales se forman del cociente de dos enteros y pueden expresarse como cifras decimales periódicas o no, mientras que los números irracionales tienen cifras decimales infinitas que no se repiten.
Este documento describe las máquinas simples, incluyendo la palanca, el plano inclinado y la rueda. La palanca es una barra rígida que gira sobre un eje llamado fulcro, y existen tres tipos de palancas. El plano inclinado reduce el esfuerzo necesario para elevar un peso mediante el uso de una rampa. La rueda es un cuerpo redondo que gira sobre un eje, y es utilizada en máquinas como poleas, rodillos y engranajes.
Faluvégi Balázs: A befektetéskezelés három forradalmaFinTechAkademia
A befektetéskezelés három forradalmának bemutatása az autóipar változásának analógiáján keresztül. Forradalom #1: 1. skálázhatóság, 2. a futószalag okozta változás, 3. Mit jelent ez a Blueopes esetén? Forradalom #2: 1. egyénre szabhatóság, 2. az új autók extra listája, 3. Hogyan valósítjuk ezt meg a Blueopes-nál kevés kérdéssel, mégis hatalmas variációs lehetőséggel? Forradalom #3: 1. társadalom- és környezettudatos befektetések (SRI), 2. Az elektromos autók feltörése, 3. SRI megvalósítása és impact számítások a Blueopes-nál.
Este documento explica las características de una progresión geométrica. Una progresión geométrica es una secuencia de números donde cada término se obtiene multiplicando el anterior por una constante llamada razón. El documento describe cómo calcular el término general y la suma de los términos de una progresión geométrica usando fórmulas matemáticas. También explica que la razón puede ser positiva o negativa y diferentes valores especiales de la razón como 1 o 0.
El documento habla sobre el mito del dios Thor en la mitología nórdica. Thor es el dios del trueno que siempre carga un poderoso martillo llamado Mjolnir, creado por enanos, con el cual produce truenos. Si pierde el martillo, este regresa mágicamente. También duplica su fuerza usando un cinturón mágico. Su mayor enemigo es la Serpiente del Mundo.
Este resumen describe la conversación entre Colin y su amigo Hassan después de que Colin fuera rechazado por Katherine. Colin se siente devastado y se ha encerrado en su habitación durante 14 horas. Hassan entra y se queja del mal olor, ya que Colin no ha limpiado el baño. Hassan intenta animar a Colin diciéndole que debe creer en Dios para ser feliz, aunque Colin no está interesado en la religión. La conversación muestra el apoyo de Hassan a Colin durante este momento difícil.
Este documento describe los principios ergonómicos para trabajar de forma segura y cómoda con computadoras. Recomienda que la pantalla, teclado, silla y mesa se ajusten a la altura y posición de los ojos y cuerpo del usuario. También enfatiza tomar descansos regulares para prevenir lesiones por estrés repetitivo.
This curriculum vitae summarizes the qualifications and experience of Nijamuddin, who has worked in production and quality control roles in the food industry in Dubai, Uzbekistan, and India. He has over 15 years of experience in positions such as Production Supervisor and Quality Controller. Nijamuddin's responsibilities have included managing production resources, meeting quality standards, developing new products, and ensuring food safety. He holds a Diploma in Food Processing Technology and additional training in food hygiene and computer skills.
El documento presenta estadísticas sobre las medallas obtenidas por diferentes países en las Olimpiadas de Tokio 2020. Estados Unidos obtuvo la mayor cantidad de medallas de oro y plata con 46 y 29 respectivamente, mientras que China obtuvo la mayor cantidad de medallas de bronce con 23. El porcentaje más alto de medallas en relación a la población lo obtuvo Estados Unidos.
Este documento presenta tres partes que involucran diferentes aplicaciones de Microsoft Office. La Parte I involucra el uso de tablas en Word para clasificar elementos de hardware y software. La Parte II requiere que se cree una tabla de medallas olímpicas en Excel y se realicen cálculos y gráficos sobre los datos. La Parte III instruye al usuario a crear una presentación de PowerPoint con tres diapositivas usando diferentes transiciones y animaciones.
Astronomy is the study of natural objects in the sky. Ancient astronomers from different cultures made observations of celestial bodies like the sun, stars, and moon. Galileo Galilei invented the first astronomical telescope in 1609, magnifying views 30 times compared to the naked eye. This allowed further study of planets and stars in space. Space exploration has developed from early observations using telescopes to modern inventions like rockets, satellites, space stations, and shuttles that allow exploration beyond Earth.
El documento celebra Halloween y agradece a los lectores por su colaboración. Brevemente menciona la fecha del 28 de octubre de 2016 y el lugar CRA Cerro de Santa Cruz.
Este documento discute los beneficios de la lactancia materna para bebés prematuros. Explica que la leche de madres de prematuros tiene mayores concentraciones de proteínas y electrolitos que ayudan su desarrollo. Además, la leche materna protege contra enfermedades a largo plazo y mejora el desarrollo cognitivo. Finalmente, concluye que la leche materna es el alimento ideal para los prematuros dado que satisface sus necesidades nutricionales y los protege de infecciones.
The International Journal of Engineering and Science (The IJES)theijes
The International Journal of Engineering & Science is aimed at providing a platform for researchers, engineers, scientists, or educators to publish their original research results, to exchange new ideas, to disseminate information in innovative designs, engineering experiences and technological skills. It is also the Journal's objective to promote engineering and technology education. All papers submitted to the Journal will be blind peer-reviewed. Only original articles will be published.
The papers for publication in The International Journal of Engineering& Science are selected through rigorous peer reviews to ensure originality, timeliness, relevance, and readability.
The International Journal of Engineering and Science (The IJES)theijes
This document summarizes a study on the effect of relative humidity on the hygroscopic growth factor and bulk hygroscopicity of water soluble aerosols. The study models the hygroscopic properties of urban aerosol components using data from the Optical Properties of Aerosols and Clouds database. It analyzes the hygroscopic growth factor and bulk hygroscopicity at relative humidities ranging from 0-99% for different aerosol models. The results show that hygroscopic growth factor increases with relative humidity while bulk hygroscopicity decreases with increasing relative humidity. The growth factor and bulk hygroscopicity also vary for the different aerosol models analyzed in the study.
Physical Characterization of a Method for Production of High Stability Suspen...Editor IJCATR
Suspensions/Dispersions are encountered in a wide range of
applications, e.g., liquid abrasive cleaners, ceramics, medicines,
inks, paints….etc. In most cases it is necessary to keep the
suspension stable for the product lifetime. A new modified
differential sedimentation measuring system is suggested and used
to identify physical parameters affecting the sedimentation in
suspensions. The technique is discussed in details. It is found that
particle sizes as well as viscosity of continuous phase are the most
important factors governing the stability of a suspension. Empirical
relations are extracted to quantitatively describe the weight effect of
each factor. The modified measuring system shows good accuracy
enough to detect fluctuations in concentration of suspended
particles due to their Brownian diffusion, as well as the particles
concentrations in the stable suspension. This study confirmed the
fact that particles diameters measured by Zetasizer are much
greater than those measured by the transmission electron
microscope. This study presents a proposal for new technique for
particle size separation based on the differential sedimentation in
viscose fluids. This new method is a differential viscosity column.
The proposed size separation technique may help to separate
engineered nano-particles with higher resolution
In this paper the Radiation Amplification Factor (RAF) was studied over Helwan (31°20'33.92"E, 29°51'46.55"N, 150m asl), it has a subtropical desert and hot climate. The ground observation of UVI which leading to this work was carried out in National Research Institute of Astronomy and Geophysics (NRIAG), Helwan, Cairo, Egypt through the period (2011 - 2015). The data of Ozone and Aerosol Index was obtained from Ozone Monitoring Instrument (OMI). This study covers the period from 2011 to 2015. Firstly, the parameters Ultraviolet index (UVI), total ozone content (TOC) and aerosol index (AI) are studied individually over all sky conditions. The radiation amplification factor (RAF) was studied over clear sky conditions, to clarification of the relativity ratio between TOC and UVI, also to estimate the dependence of UVI on AI changes.
This document summarizes a study that evaluated two methods for estimating age at death using dental analysis: Kilian's method and Kashyap and Koteswara Rao's method. 63 teeth were histologically examined and scored based on six dental markers related to aging. Regression analysis found that Kilian's method, which uses subjective scoring, produced a more accurate age estimation with a mean error of 4.97 years compared to 8.32 years for Kashyap and Koteswara Rao's quantitative method. Identification tables were also created using Kilian's method to classify individuals into broad age categories with a mean error of 6.58 years. The study found that dental analysis can provide a relatively reliable estimation of age at
It is an scientific article published in the Journal of Aerosol Science. The topic is within the subjects of Materials/Environmental sciences. The publication can be also downloaded for free from the below link:
http://www.sciencedirect.com/science/article/pii/S0021850215000919
This document describes a system developed to assess the stability of airborne nanoparticle agglomerates under aerodynamic shear. The system includes an aerosolization device that uses a fluidized bed process to generate stable aerosols from dry nanopowders. A critical orifice is then used to apply varying levels of shear force to the aerosols by inducing turbulence as they pass through. Changes in particle size distribution and morphology after passing through the orifice are analyzed to test the deagglomeration potential of different nanomaterials. Various nanomaterials were tested to investigate how their properties like composition, size, and shape influence stability.
This study investigated the relative influences of apatite crystal orientations and intracortical porosity on the elastic anisotropy of human cortical bone. Experimental measurements of elastic constants from human femoral bone specimens exhibited orthotropic elasticity. Predictions from a micromechanical model accounting for apatite crystal orientations accurately captured the transverse isotropy observed in the longitudinal-circumferential plane but underestimated orthotropy. A finite element model accounting for intracortical porosity predicted orthotropy but underestimated elastic anisotropy. Only a combined model accounting for both apatite crystal orientations and intracortical porosity provided predictions within 10% of experimental measurements, suggesting both microstructural features contribute significantly to cortical bone's elastic
1. The document discusses methods for separating forced and unforced climate variability and identifying patterns of multidecadal predictability.
2. A new statistical method is used to identify an unforced, multidecadal sea surface temperature pattern in simulations and observations.
3. Forced warming is estimated to contribute 0.1K per decade, while an identified internal multidecadal pattern explains about 0.1C fluctuations in global average sea surface temperature over decades.
The document summarizes a study that used electron backscatter diffraction (EBSD) to measure the development of subgrain misorientation angles with increasing strain in dry synthetic sodium chloride (NaCl) deformed at elevated temperatures. The study found that average subgrain boundary misorientations increased with strain following a power law relationship. The average misorientations were influenced by grain orientation and size, suggesting texture and grain size may also impact the misorientation-strain relationship. The results indicate average subgrain boundary misorientations could provide a method for estimating strain from dislocation creep, though other factors like stress may also influence misorientations.
This document discusses using genetic programming to determine the most effective parameters that influence scour depth at seawalls. Previous studies have developed equations to predict scour depth but they considered a limited number of parameters and had uncertainties. The genetic programming approach was able to evolve models that identify the most significant parameters and omit non-significant ones. The results indicated that relative scour depth is most affected by the reflection coefficient and water depth at the toe, while the influence of sediment grain size is negligible.
Turbulence structure behind the shock in canonical shockvortical turbulence ...Jovan Belite Squad
This document discusses a study using direct numerical simulation (DNS) to examine the interaction between isotropic turbulence and a normal shock wave. High-resolution simulations were performed across a range of shock Mach numbers (1.1-2.2) and turbulent Reynolds numbers (10-45). The results showed that turbulence quantities from DNS converge to predictions of linear interaction analysis (LIA) as the turbulent Mach number decreases, demonstrating the importance of LIA. LIA was also extended to compute full post-shock flow fields, revealing how the shock significantly changes turbulence structures through symmetrization and increased strain-rotation correlation.
This document summarizes techniques for online particle sizing, especially for wet processes and nanoparticles. It discusses common sizing methods, challenges of online sizing like high concentration and morphology, and advances to address these difficulties. These include modeling approaches to account for multiple scattering, techniques to suppress scattering effects, and the use of chemometrics to model sizing results and process parameters from instrument data. Wet media milling for nanoparticle production is also briefly reviewed, outlining variables that influence particle size and strategies for efficient milling.
Jet reorientation in central galaxies of clusters and groups: insights from V...Sérgio Sacani
Recent observations of galaxy clusters and groups with misalignments between their central AGN jets
and X-ray cavities, or with multiple misaligned cavities, have raised concerns about the jet – bubble
connection in cooling cores, and the processes responsible for jet realignment. To investigate the
frequency and causes of such misalignments, we construct a sample of 16 cool core galaxy clusters and
groups. Using VLBA radio data we measure the parsec-scale position angle of the jets, and compare
it with the position angle of the X-ray cavities detected in Chandra data. Using the overall sample
and selected subsets, we consistently find that there is a 30% – 38% chance to find a misalignment
larger than ∆Ψ = 45◦ when observing a cluster/group with a detected jet and at least one cavity. We
determine that projection may account for an apparently large ∆Ψ only in a fraction of objects (∼35%),
and given that gas dynamical disturbances (as sloshing) are found in both aligned and misaligned
systems, we exclude environmental perturbation as the main driver of cavity – jet misalignment.
Moreover, we find that large misalignments (up to ∼ 90◦
) are favored over smaller ones (45◦ ≤ ∆Ψ ≤
70◦
), and that the change in jet direction can occur on timescales between one and a few tens of Myr.
We conclude that misalignments are more likely related to actual reorientation of the jet axis, and we
discuss several engine-based mechanisms that may cause these dramatic changes.
The document discusses several key points:
1) There have been few ecosystem-scale experiments investigating the combined effects of increased CO2 and rising temperatures on ecosystems, though these interactions are important to understand for predicting future impacts.
2) Factorial experiments examining multiple factors can be difficult to design and interpret, but are still important for testing models and accounting for potential surprises from interactions.
3) Available data on forest responses to climate change come from limited experimental approaches like soil warming or small tree plots, rather than whole-ecosystem experiments, making it difficult to fully understand interactions between CO2 and temperature at ecosystem scales.
The Effect of Capilliary Number on Leading Edge Cavitation Cell Size, THESIS ...Dylan Henness
The document summarizes an experimental study that analyzed the effect of Capillary number on leading edge cavitation cell size for a NACA 16-029 hydrofoil profile. The experiment varied both cavitation number from 0.25 to 0.52 and Reynolds number from 3.5x106 to 7.0x106. High-speed imaging and still images were captured of the leading edge cavitation cells at different flow conditions to analyze cell size variations with changing Capillary number. The results will provide insights into global cavitation physics including cavity growth and collapse processes.
Effect of the Human Eye Cornea Material Property on Measurement of the Intrao...IDES Editor
A quarter 3D model of cornea-aqueous humor
employing elastic anisotropic formulation in collaboration
with Goldmann appalanation tonometer (GAT) action is
investigated in order to examine the relation between the
material property variation and the deviation from the true
pressure inside the human eye utilizing finite element
method. In addition to that, the effect of the corneal thickness
variation has also been studied. However, the clinical
experimental data show tremendous variation between true
intraocular pressures (IOPTs) with those of gauged intraocular
pressure (IOPGs). Numerical results establish how these
parameter effect the readings. The present model has also
been compared with the previous works and has been compared
with some experimental data. This comparison establishes
correctness of the proposed assumptions.
Seven marine sediment core sections were scanned using XRF at seven international labs to compare results. Raw element counts per second (cps) differed between labs but element ratios were more comparable. Four labs also scanned sediment pellets of known composition to calibrate cps to concentrations using linear and log-ratio methods. Log-ratio calibrations produced results more comparable between labs. Small-scale features are often not reproducible. Guidance is provided on practical XRF calibration and recommendations made for interpreting and comparing XRF data between labs.
This document summarizes a study that estimated solar UV-B radiation levels at Visakhapatnam, India from 2005-2013 using a regression model incorporating satellite-measured column ozone levels and solar zenith angle. The model was developed using earlier UV-B measurements and ozone data from 1989-1993. Analysis found seasonal variations in ozone but no significant long-term trends in estimated UV-B levels. The study concluded the data could help assess biological effects of UV-B radiation at this location over time.
This document examines how the assumption of homogeneous vs heterogeneous radioactive contamination in soil/sediment impacts the external radiation dose rates of fauna. It analyzes contamination profiles from sediment samples in Canada and soil samples in Austria involving various radionuclides. Dose conversion coefficients are calculated using a dosimetry model for different organisms, locations within the contaminated media, and exposure scenarios. The results show dose rates can vary by three orders of magnitude depending on the specific situation. The assumption of homogeneous contamination is not always conservative.
1. Sensitivity of particle loss to the Kelvin effect in LES of young
contrails
Aniket R. Inamdar1
, Alexander D. Naiman2
, Sanjiva K. Lele1,2
, and Mark Z. Jacobson3
1
Dept. of Mech. Engg.
2
Dept. of Aero. & Astro.
3
Dept. of Civil & Env. Engg.
1,2,3
Stanford University, California, USA
Correspondence to: Aniket R. Inamdar (ainamdar@stanford.edu)
Abstract. Different treatments of the Kelvin effect in LES modeling of early contrails are shown to cause variations in the
survival rate of ice particles by up to a factor of 4 and in optical depth and mean particle size by up to 50%. The Kelvin effect
which varies exponentially with particle size, can reduce or even suppress the impact of other important ambient parameters,
such as ice supersaturation, on particle survival rate. Lowering or neglecting the Kelvin effect is shown to substantially alter the
evolution of the ice particle size distribution and delay the onset of particle loss. A strongly Kelvin effect dependent exponential5
relation between particle survival rate and particle size is shown for high EIsoot (O(1015
)).
1 Introduction
While the best estimates for climate impact in terms of global radiative forcing for aviation CO2 emissions (28×10−3
Wm−2
)
are comparable with those for linear contrails (11.8×10−3
Wm−2
) and Aviation Induced Cloudiness(AIC, 33×10−3
Wm−2
),
the uncertainties in these estimates are substantially larger for contrails and AIC (Lee et al., 2009). Such uncertainties arise due10
to inadequate or inaccurate representations of contrails in General Circulation Models(GCMs) which stem from a low level
of scientific understanding of contrail evolution (Penner et al., 1999). With a consensus on the need to further this scientific
understanding, recent work on aircraft contrails has concentrated on the detailed study of young contrails as differences in
evolution of young contrails are seen to have lasting effects (Unterstrasser and Gorsch, 2014). There are obvious difficulties
in sufficiently sampling cross-sections of young contrails and measuring the ambient conditions they are formed in. Densely15
sampled in-situ measurements are indeed few and thus numerical simulation of individual contrails in LES frameworks has
become a means of investigation (Chlond, 1998; Lewellen and Lewellen, 1996, 2001; Lewellen et al., 2014; Gierens, 1996;
Jensen et al., 1998; Paoli et al., 2003, 2004; Paoli and Garnier, 2005; Huebsch and Lewellen, 2006; Shirgaonkar, 2007; Un-
terstrasser et al., 2008; Unterstrasser and Gierens, 2010a, b; Unterstrasser and Solch, 2010; Naiman, 2011; Paoli et al., 2013;
Jessberger et al., 2013; Inamdar et al., 2013; Unterstrasser et al., 2014; Unterstrasser and Gorsch, 2014; Unterstrasser, 2014;20
Inamdar et al., 2014; Picot et al., 2015).
Ice particle transport may be modeled using Lagrangian Particle Tracking (LPT), binned microphysics or bulk microphysics.
Previous work using these approaches is summarized in Paoli and Shariff (2016). Within the simulation approaches, those
1
Atmos. Chem. Phys. Discuss., doi:10.5194/acp-2016-817, 2016
Manuscript under review for journal Atmos. Chem. Phys.
This is just a preview and not the published paper.
c Author(s) 2016. CC-BY 3.0 License.
2. with LPT are considered to provide more plausible results (Unterstrasser and Solch, 2010), although numerical schemes,
initialization procedures and model assumptions vary. Numerically observed sensitivities of particle survival rates, mean size
and mean optical extinction to parameters such as EIsoot and ice supersaturation(RHi) reported in the literature (Picot et al.,
2015; Unterstrasser, 2014; Naiman et al., 2011) have discrepancies that can be large. In Unterstrasser (2014)(their “Gaussian"
cases in Fig. 13 and RHi = 130% in Fig. 9), they observe 40% to 70% survival rates for RHi ranging from 120% to 140%5
and 50% to 90% survival rates for a reduction in EIsoot by a factor of 10. In Picot et al. (2015) (their cases 2 and 4 with
Kelvin effect in Fig. 19) a change in RHi from 110% to 130% increases survival rate from 65% to near 100% while Naiman
et al. (2011) (their Figs. 13,14) see negligible sensitivity of survival rates to RHi ranging from 110% to 130% and an increase
of survival rate from 20% to 90% due to a decrease in EIsoot by a factor of 10. In Inamdar et al. (2013) and Lewellen et al.
(2014), neglecting the Kelvin effect has a dramatic order-of-magnitude impact on particle survival rates for both young and10
aged contrails. Here we address the important question of whether the observed discrepancies are due to modeling assumptions
and differences in simulation initializations.
The Kelvin effect raises the apparent vapor saturation pressure over a curved ice surface relative to a flat one (Paoli and
Shariff, 2016; Jacobson, 2005; Lewellen et al., 2014), for a given temperature, T, as follows:
pkelvin
sat = p0
sat exp(
ak
rp
)
Φ(r,ak(σ,T ))
ak =
2σMH2O
RTρp
(1)15
where rp is the radius of curvature of the surface, σ is the ice-vapor surface tension, MH2O is the molecular mass of water, R is
the universal gas constant, and ρp is the density of ice. In Naiman (2011), Naiman et al. (2011), Inamdar et al. (2013), Inamdar
et al. (2014), Inamdar et al. (in progress) the parameter ak was explicitly calculated as a function of T but in other studies the
Kelvin effect is neglected (Paoli et al., 2013; Paugam et al., 2010; Paoli et al., 2004) or a fixed order-of-magnitude value of ak
is used (Picot et al., 2015). It is unclear to the authors exactly how the Kelvin effect is modeled in (Solch and Karcher, 2010)20
and studies employing the same approach (Unterstrasser, 2014; Unterstrasser and Gorsch, 2014; Unterstrasser et al., 2014).
Given the wide range of sensitivities of particle survival to EIsoot and RHi reported in the above-mentioned studies that use
different modeling approaches, it is useful to understand how various treatments of the Kelvin effect can affect properties of
young contrails, primarily particle survival rates during the vortex phase.
Exclusion of jet exhaust enthalpy is a common modeling assumption (Unterstrasser, 2014; Unterstrasser and Gorsch, 2014;25
Unterstrasser et al., 2014; Jessberger et al., 2013; Unterstrasser and Solch, 2010) as it is expected to not have any persistent
impact (Schumann, 2012)(their Appendix A6). Keeping in mind that several in-situ measurements provide data for young
contrails (Febvre et al., 2009; Voigt et al., 2010; Gayet et al., 2012) and that Unterstrasser (2014)(their “Gaussian" cases in
Fig. 13) observes a delayed onset of particle loss (∼ 40s) as compared to Naiman et al. (2011)(their Fig. 13) and Inamdar
et al. (2013) (their case “SP" in Fig. 7) (∼ 20s), it is necessary to examine the impact of this assumption on the LES of young30
contrails.
2
Atmos. Chem. Phys. Discuss., doi:10.5194/acp-2016-817, 2016
Manuscript under review for journal Atmos. Chem. Phys.
This is just a preview and not the published paper.
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3. 2 LES framework, ice microphysics and simulation cases
The LES framework and Ice Microphysics are identical to Naiman (2011) and Naiman et al. (2011) and hence are not detailed
here. We perform 12 simulations up to a contrail age of 600 s. Ambient conditions listed in Table 1 were chosen as they are
representative of a cruise altitude of 10.5 km (Wilkerson et al., 2010) and are conducive to formation of persistent contrails.
Aircraft parameters that remain constant across simulations are also listed in Table 1. The grid sizes and resolutions are as5
in Naiman et al. (2011)(their Table 5). The sizes and locations of jet exhaust plumes and vortex cores in the domain are also
listed in Table 1, where ∆xjet/vort is the initial span-wise separation between the pairs of jet exhaust plumes or vortices and
∆yjet−vort is the initial vertical separation between the jets and vortices, in units of wingspans.
In Table 2, we have listed the simulations performed. We are able to isolate the impact of exhaust enthalpy, EIsoot, RHi and
modeling of the Kelvin effect. Cases with EIsoot = 1014
and no Kelvin effect are not performed as they are expected to have a10
near 100% survival rate (Picot et al., 2015). For the aircraft parameters and the EIsoot values considered ({1015
,1014
}#kg−1
),
the initial ice particles is {5.64 × 1012
,5.64 × 1011
}#m−1
.
Unterstrasser (2014) acknowledges that a uniform initialization of ice particles centered around the vortex core is unrealistic
and considers the impact of non-uniform (specifically “Gaussian") initialization of ice particle density away from vortex cores
inline with Naiman et al. (2011) but does not include jet exhaust heat. There they observe a substantial difference in the survival15
rates between their uniform and Gaussian initializations for low and high relative humidities w.r.t ice and hence, we have not
considered uniform initialization of ice particles.
The size distribution is initialized to be unimodal. Previous studies (Unterstrasser, 2014; Lewellen et al., 2014) have ex-
amined the impact of varying initial size distribution but until measurements of particle sizes in contrails only a few seconds
old become available this “irreducible uncertainty" (Unterstrasser, 2014) in the “true" initial size distribution will persist in20
simulation efforts. Hence, we have not varied the initial size distribution.
For cases with a temperature dependent Kelvin effect, we choose σ = 0.107 Jm−2
(range: 0.100-0.111 Jm−2
(Prup-
pacher and Klett, 2010)) and with spherical ice particles ρp = 917 kgm−3
. In Table 1, the range of values of ak for σ ∈
{0.100,0.107,0.111} Jm−2
and T ∈ {205,219.9,225} K are listed and are comparable to Lewellen et al. (2014).
3 Results25
In this section, we show the results of our simulations and highlight the impact of the Kelvin effect treatment on particle
survival rates, mean size and mean extinction. We highlight qualitative similarities with earlier studies and reasons for observed
differences.
In Fig. 1(a,Top), the evolution of volume-weighted plume temperature in excess of the ambient temperature (henceforth
excess temperature) is shown for all the cases (plume volume is defined by the isosurface of particle concentration = 1 #cm−3
).30
The initial rapid decline (barring cases ‘U#’) is the rapid cooling due to the warm jet exhaust plume being inducted by the
wake vortices. It is clear that the plume temperature remains above the ambient (by ∼ 0.3 K) for a majority of the vortex phase
and, barring cases ‘U#’, its variability is less than 0.1 K, i.e. the plume temperature in the vortex phase is “constant" (Inamdar
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4. et al., 2016). This behavior will be shown to be a universal phenomenon across variations in aircraft types, ambient conditions
and microphysical modeling in an upcoming study by the same authors (Inamdar et al., in progress). Following the destruction
of the coherent vortex pair, we see the plume temperature relaxing to the ambient temperature as ambient turbulence mixes
the warm plume with the cool ambient. In cases ‘U#’, we observe the adiabatic heating of the wake as it descends through the
stably stratified ambient and the turbulent relaxation to the ambient temperature during the early dispersion phase. Note that5
the peak plume temperature reached in cases ‘U#’ is lower than that in cases with jet exhaust heat.
In Fig. 1(b,Top), the Kelvin correction Φ(r,ak(σ,T)) for ak(σ = 0.107 Jm−2
,T = 219.9 K) with bounds using the mini-
mum and maximum values of ak(σ,T) from Table 1 along with ak = 10−9
m is plotted as a function of particle radius. It is
clear that Φ(r,ak(σ,T)) is a weak function of both σ and T, but ak = 10−9
m results in substantially lower Kelvin correction
for smaller particles(r < 0.1 µm). The increase in plume temperature coupled with growth of ice particles results in the reduc-10
tion of the plume RHi (Naiman et al., 2011; Lewellen et al., 2014). In Fig. 1(b,Bottom) we illustrate the size dependence of
excess vapor pressure available for particles for ak ∈ {∼ 2.29×10−9
,10−9
} m at Tplume = (219.9+0.3) K for representative
reduced plume supersaturations of RHiplume ∈ {105,101}%. We can see that smaller particles experience apparent subsatu-
ration, the strength of which is strongly influenced by treatment of Kelvin effect. However, the contrail ice mass is insensitive
to both EIsoot and the Kelvin effect as seen in Fig. 1(a, Bottom). Thus, larger particles grow at the expense of smaller particles15
as suggested in Inamdar et al. (2016).
In Fig. 2(Top), the particle survival rate is shown for all the cases. It is important to note that cases with lower Kelvin effect
have a delayed onset of particle decay for both high and low RHi values (this effect is prominently seen in cases with high
EIsoot)(Naiman et al., 2011; Inamdar et al., 2013; Unterstrasser, 2014; Lewellen et al., 2014). Also, the delay in onset of
decay due to lower RHi is exacerbated due to lower Kelvin effect. The impact of lower Kelvin effect is most prominently20
felt for higher EIsoot as it affects smaller particles (typically < 0.1 µm) and for the same exhaust vapor mass, lower EIsoot
results in larger ice particles at our simulation initialization (Paoli et al., 2013). Cases with lower Kelvin effect are seen to have
higher survival rates and this difference is substantial for high EIsoot. Qualitatively, the low Kelvin cases with high EIsoot are
observed to produce similar survival rates and trends w.r.t sensitivity to RHi as seen in Unterstrasser (2014)(their “Gaussian"
cases in Fig. 13) by ∼ 5min. The ∼ 99% survival rate at 2min. for high RHi and low EIsoot is comparable to Picot et al.25
(2015) (their run 2 in Table 3).
The apparent subsaturation experienced by small particles shows stronger dependence on the treatment of Kelvin effect than
to RHi (see Fig. 1(b,Bottom)). It is for this reason that the relative impact of RHi on particle survival is suppressed in high
EIsoot and high Kelvin cases. In cases that exclude jet exhaust heat, we observe a delay in the onset of particle decay. This
may be due to the lower plume temperature experienced by the ice particles as seen in Fig. 1. But this effect is indeed reduced30
to insignificant by ∼ 5 min. As expected, we observe a very high survival rate in cases without Kelvin effect and high EIsoot.
In Fig. 2(Center, Bottom) evolution of mean particle size(radius) and a log-log plot of particle survival rate vs. mean particle
size are shown. As suggested in Inamdar et al. (2016), in case of high EIsoot, we observe an exponential relation between
survival rate and size during the vortex phase, seen in the linearity of the plots in Fig. 2(Bottom). This relationship is only
weakly dependent on RHi as the plume temperature remains constant during the vortex phase. But, as the plume temperature35
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5. relaxes to the ambient temperature, we observe the plots for high and low RHi begin to diverge. The change in slope as the
Kelvin effect is reduced can also be seen. As more particles survive, mean particle size is lowered due to competition for the
same vapor mass (Inamdar et al., 2013; Lewellen et al., 2014). The onset of decay is seen to occur at the same particle size,
given the EIsoot (∼ 0.75 µm for 1015
and ∼ 2 µm for 1014
). Since it takes longer for the mean size to grow to these “critical"
sizes in ambients with lower RHi (see Fig. 3), the onset of decay is delayed in these cases as seen in Fig. 2(Top).5
In Fig. 3, we have shown the particle size PDFs at 1 s, 5 s, 15 s, 30 s, 45 s, 60 s, 90 s, 120 s and 300 s. The impact of Kelvin
effect on the tail of the size PDF is clearly visible in the presence of large number of small particles for cases with low and no
Kelvin effect at later times. We also see that the PDF peaks at lower values for low RHi cases, as is expected. The early PDFs
at t = 1 s and t = 5 s are indifferent to the Kelvin effect and qualitatively similar to Karcher and Yu (2009). We note that PDFs
of cases with low RHi take longer to thicken and develop the characteristic size PDF associated with contrails (Naiman et al.,10
2011; Picot et al., 2015; Lewellen et al., 2014). Since the low RHi cases need longer to develop a tail of small particles, the
onset of particle loss is also delayed as compared to cases with high RHi. While this is in contrast to Unterstrasser (2014) and
Picot et al. (2015), we strongly suspect this is due to the fact that there the initial size PDF is not unimodal. In Unterstrasser
(2014), initializations with thicker size PDFs see an early onset of decay.
Finally, in Fig. 4, the mean optical depth as calculated in Picot et al. (2015) along with the volume-weighted mean extinction15
(plume volume as defined earlier) is shown for the high EIsoot cases only, since there is essentially no impact of Kelvin effect
for low EIsoot. Though, we report for low Kelvin effect and low EIsoot a mean optical depth of 0.19 for RHi 130% at 4 min
and this value compares well with Picot et al. (2015) (their Fig. 19). Also, we report an optical depth of 0.1 and extinction of
1.5 km−1
for low EIsoot and RHi of 110% at t = 100 s which compares reasonably with Jessberger et al. (2013) (their Table
4, unit A319 and RHi 103%) considering our slightly higher RHi and larger aircraft.20
In Jessberger et al. (2013) (their Table 5, unit A319, RHi 120%, EIsoot = 1015
), the CoCiP model that does not consider
Kelvin effect reports an optical depth of 0.38 and extinction of 2.7 km−1
(at ∼ 100 s and assumed survival rate of 0.5). A
similar survival rate (∼ 0.6) at the same EIsoot is observed for low Kelvin and hence we compare their results with this case
where we report an optical depth of 0.45 and extinction of 5 km−1
- reasonable considering our larger aircraft size and higher
RHi. A number of reported values of optical depth are listed in Paugam et al. (2010) (their Table 3). For a B747 and RHi25
130%, the computed mean optical depth (using LES (Unterstrasser and Gierens, 2010a)) up to 35 min is 0.4 which compares
well with the value predicted by our high EIsoot, RHi 130% and low Kelvin, 0.38 (B747 is marginally larger than the aircraft
size considered here).
While the impact of modeling of Kelvin effect on optical depth is not negligible for high EIsoot, it is the most pronounced in
highly supersaturated conditions. We clearly see how lowering the Kelvin effect exacerbates the impact of RHi on the optical30
depth. The presence of a large number of smaller particles in the low and no Kelvin cases can increase the optical depth by up
to 50%.
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6. 4 Conclusions
Neglect or a simple order-of-magnitude accounting of the Kelvin effect in LES of young contrails may produce substantially
higher particle survival rates and also exacerbate the impact of ambient ice supersaturation, especially for high soot emission
indices. There is a need for in-situ measurements of young contrails (aged a few seconds up to a few minutes) in weakly and
strongly supersaturated ambients to guide future simulation efforts in this field.5
1. The discrepancies in particle survival rates and sensitivities to RHi observed in LES of early contrails using different
modeling approaches are primarily due to the different treatment of the Kelvin effect.
2. Particle survival rate and optical depth are the most sensitive to the treatment of the Kelvin effect for high EIsoot. This
sensitivity is reduced to negligible by lowering the EIsoot by a factor of 10.
3. In the absence of in-situ data for high EIsoot and high RHi, it remains an open question as to which modeling approach10
is more reliable in high soot and high supersaturation regimes, though a temperature dependent treatment of the Kelvin
effect seems more plausible.
4. Lowering of the Kelvin effect and exclusion of jet exhaust heat both result in a delayed onset of particle loss, though the
effect of exhaust heat is not seen to be persistent.
5. An exponential relation exists in the vortex phase between particle survival rate and mean particle size for high EIsoot.15
6. Onset of particle loss is seen to occur at a “critical" mean particle size that is EIsoot-dependent. This observation coupled
with the slower growth of ice particles in plumes experiencing lower ambient RHi helps explain the delayed onset of
particle loss in cases with lower RHi.
5 Code and data availability
The code and data used in this study is readily available upon request to the corresponding author.20
Author contributions. A. R. Inamdar and A. D. Naiman performed the simulations while A. R. Inamdar analyzed the simulation data and
composed the manuscript under the supervision of S. K. Lele and M. Z. Jacobson.
Competing interests. The authors declare that they have no conflict of interest.
Acknowledgements. This project is sponsored by the Federal Aviation Administration under the award number DTFAWA-05-D-0006. Tera-
Grid and XSEDE resources LONI, NCSA, KRAKEN and STAMPEDE under grant number TG-CTS080041N were used for this research.25
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9. Table 1. List of Variables
Ambient Conditions
Parameter Value Parameter Value
Air Density (ρ0) 0.387 kg m−3
Relative Humidity 130%,
w.r.t Ice (RHi) 110%
Ambient Pressure (p0) 2.45×104
Pa Ambient Temperature (T0) 219.9 K
Shear 0 s−1
Brunt-Väisälä freq. (Nbv) 0.01 s−1
Ambient Turbulence ( ) 1 × 10−4
m2
s−3
Turb. Kinetic Energy (k) 1 × 10−2
m2
s−2
Aircraft Parameters
Parameter Value Parameter Value
Wingspan (B) 50 m Weight (W) 136814kg
Circulation Γ0 370 m2
s−1
Fuel Burn ( ˙mf ) 5.64 ×10−3
kg m−1
Engine Efficiency (η) 0.3 Exhaust Heat 43 × 106
(1 − η) ˙mf J m−1
Vortex & Jet Exhaust Initialization Parameters
Parameter Value Parameter Value
rjet 7 m rvort 3.3 m
∆xjet 0.52 ∆xvort
π
4
∆yjet−vort 0.26
Range of Values for Kelvin Parameter ak(10−9
m)
σ = 0.100Jm−2
σ = 0.107Jm−2
σ = 0.111Jm−2
T = 205K 2.30 2.47 2.56
T = 219.9K 2.15 2.29 2.38
T = 225K 2.10 2.25 2.33
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10. Table 2. List of LES Cases
Case Name Case Description Legend
Baseline (B0) EIsoot = 1015
, RHi = 130%, ak = f(T) solid black
B1 EIsoot = 1015
, RHi = 110%, ak = f(T) dashed black
B2 EIsoot = 1015
, RHi = 130%, ak = 10−9
m solid blue
B3 EIsoot = 1015
, RHi = 110%, ak = 10−9
m dashed blue
B4 EIsoot = 1015
, RHi = 130%, ak = 0m solid red
B5 EIsoot = 1015
, RHi = 110%, ak = 0m dashed red
L0 EIsoot = 1014
, RHi = 130%, ak = f(T) solid green
L1 EIsoot = 1014
, RHi = 110%, ak = f(T) dashed green
L2 EIsoot = 1014
, RHi = 130%, ak = 10−9
m solid cyan
L3 EIsoot = 1014
, RHi = 110%, ak = 10−9
m dashed cyan
U0 Same as B0, but no jet exhaust enthalpy solid magenta
U1 Same as B1, but no jet exhaust enthalpy dashed magenta
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11. (a) Evolution in Time (b) Size Dependence
Figure 1. [a] Evolution of (Top) Excess Plume Temperature and (Bottom) Contrail Ice Mass. [b] Size Dependence of (Top) Kelvin correction
and (Bottom) Excess Vapor Pressure
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12. (a) EIsoot = 1015
(b) EIsoot = 1014
Figure 2. (Top) Fraction of surviving particles vs. Time, (Center)Mean Particle Size vs. Time, (Bottom) Fraction of surviving particles vs.
Mean particle size
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13. (a) t = 1s (b) t = 5s (c) t = 15s
(d) t = 30s (e) t = 45s (f) t = 60s
(g) t = 90s (h) t = 120s (i) t = 300s
Figure 3. PDF of Particle Size Distribution
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14. (a) Mean Optical Depth (b) Mean Extinction
Figure 4. Evolution of mean optical properties
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