Download or read book Molecular Dynamics Study of the Kinetics of Heterogeneous Ice Nucleation written by Chu Li and published by . This book was released on 2018 with total page 101 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Investigating Ice Nucleation at Negative Pressures Using Molecular Dynamics written by and published by . This book was released on 2021 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Abstract : Atmospheric scientists and climate modelers are faced with uncertainty around the process of ice production in clouds. While significant progress has been made in predicting homogeneous and heterogeneous ice nucleation rates as a function of temperature, recent experiments have shown that ice nucleation rates can be enhanced without decreasing temperature, through various mechanical agitations. One hypothesis for these findings is that mechanisms of stretching water and thereby inducing negative pressure in the liquid could lead to an increase in freezing rate. To better understand the viability of this concept, the effect of negative pressure on ice nucleation rates needs to be explored. To that end, we have conducted molecular dynamics simulations of water at negative pressures. Homogeneous ice nucleation rates for the ML-mW and mW water models are evaluated at pressures ranging from atmospheric to -1000 atm, using Forward Flux Sampling and constant cooling simulations. We find that the density difference between ice and liquid water is central in determining the increase in nucleation rate with negative pressure. With these results, we analyze an equation that has been posed as a first order approximation to quantify how nucleation rate changes with negative pressure. The equation predicts the slope of lines of constant nucleation rate in temperature--pressure coordinates, shining a light on the importance of the water density anomaly in determining the slope. We conclude that this linear approximation works well for the mW and ML-mW water models and can be useful in making experimental predictions to advance the study of ice nucleation mechanisms.
Download or read book Furthering Our Understanding of Heterogeneous Ice Nucleation with Molecular Simulation written by and published by . This book was released on 2014 with total page 207 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Furthering Our Understanding of Heterogeneous Ice Nucleation with Molecular Simulation written by Stephen James Cox and published by . This book was released on 2014 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Nucleation of Water written by Ari Laaksonen and published by Elsevier. This book was released on 2021-11-25 with total page 296 pages. Available in PDF, EPUB and Kindle. Book excerpt: Nucleation of Water: From Fundamental Science to Atmospheric and Additional Applications provides a comprehensive accounting of the current state-of-the-art regarding the nucleation of water. It covers vapor-liquid, liquid-vapor, liquid-ice and vapor-ice transitions and describes basic kinetic and thermodynamic concepts in a manner understandable to researchers working on specific applications. The main focus of the book lies in atmospheric phenomena, but it also describes engineering and biological applications. Bubble nucleation, although not of major atmospheric relevance, is included for completeness. This book presents a single, go-to resource that will help readers understand the breadth and depth of nucleation, both in theory and in real-world examples. Offers a single, comprehensive work on water nucleation, including cutting- edge research on ice, cloud and bubble nucleation Written primarily for atmospheric scientists, but it also presents the theories in such a way that researchers in other disciplines will find it useful Written by one of the world’s foremost experts on ice nucleation
Download or read book Kinetics of Ice Nucleation from Water and Electrolyte Solutions written by George R. Wood and published by . This book was released on 1969 with total page 188 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Ice Adhesion written by K. L. Mittal and published by John Wiley & Sons. This book was released on 2020-12-15 with total page 704 pages. Available in PDF, EPUB and Kindle. Book excerpt: This unique book presents ways to mitigate the disastrous effects of snow/ice accumulation and discusses the mechanisms of new coatings deicing technologies. The strategies currently used to combat ice accumulation problems involve chemical, mechanical or electrical approaches. These are expensive and labor intensive, and the use of chemicals raises serious environmental concerns. The availability of truly icephobic surfaces or coatings will be a big boon in preventing the devastating effects of ice accumulation. Currently, there is tremendous interest in harnessing nanotechnology in rendering surfaces icephobic or in devising icephobic surface materials and coatings, and all signals indicate that such interest will continue unabated in the future. As the key issue regarding icephobic materials or coatings is their durability, much effort is being spent in developing surface materials or coatings which can be effective over a long period. With the tremendous activity in this arena, there is strong hope that in the not too distant future, durable surface materials or coatings will come to fruition. This book contains 20 chapters by subject matter experts and is divided into three parts— Part 1: Fundamentals of Ice Formation and Characterization; Part 2: Ice Adhesion and Its Measurement; and Part 3: Methods to Mitigate Ice Adhesion. The topics covered include: factors influencing the formation, adhesion and friction of ice; ice nucleation on solid surfaces; physics of ice nucleation and growth on a surface; condensation frosting; defrosting properties of structured surfaces; relationship between surface free energy and ice adhesion to surfaces; metrology of ice adhesion; test methods for quantifying ice adhesion strength to surfaces; interlaboratory studies of ice adhesion strength; mechanisms of surface icing and deicing technologies; icephobicities of superhydrophobic surfaces; anti-icing using microstructured surfaces; icephobic surfaces: features and challenges; bio-inspired anti-icing surface materials; durability of anti-icing coatings; durability of icephobic coatings; bio-inspired icephobic coatings; protection from ice accretion on aircraft; and numerical modeling and its application to inflight icing.
Download or read book Chemical Characterization of Heterogeneous Ice Nuclei in the Atmosphere written by Sarah Sihvonen and published by . This book was released on 2016 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Aerosol particles impact the climate by serving as the seeds to form water droplets and ice to form clouds. However, these aerosol-cloud interactions are the least understood aspect of our understanding of the climate system. Mineral dust aerosol is the largest global source of ice nucleating particles. During atmospheric transport, mineral dust can be exposed to sulfuric acid, which has been shown to decrease the ice nucleation activity of these particles. Many explanations for this observation, such as chemical changes to the surface or product formation that blocks active sites, have been suggested. Our research focused on building a molecular picture of these surfaces to understand why sulfuric acid exposure reduces the ice nucleation activity of clay minerals such as kaolinite. We performed studies using X-ray diffraction and solid state NMR that investigate the changes that clay minerals undergo as a result of acid exposure. We are the first to show that the formation of a product on the surface of kaolinite was responsible for the decreased ice nucleation activity, not surface changes to the mineral itself. We continued to study aerosol-cloud interactions by using parcel models that explore the impact of ice growth surface kinetics on the competition between heterogeneous and homogeneous ice nucleation in clouds. We found that impaired growth of ice favors homogeneous freezing. The parcel models will be expanded to include our work on clay minerals to explore the impact of chemical aging of ice nuclei on overall cloud properties. We also studied the effect of acidic-processing on coal fly ash samples. Coal fly ash has been found to have a similar atmospheric impact as mineral dust, but is studied to a lesser extent. Like mineral dust, coal fly ash can serve as a source of bioavailable iron to phytoplankton in nutrient limited regions of the ocean. Fly ash has also been found to serve as an ice nucleating material. We performed aqueous sulfuric acid-treatment on fly ash samples representative of the types produced in the United States. We found that a soluble salt, gypsum (hydrated calcium sulfate), formed on three out of four samples. The most iron rich sample did not react with sulfuric acid. However, acidic-processing was shown to increase the amount of soluble iron which has implications for the biogeochemical cycle. These results also demonstrate that further work investigating these fly ash systems is warranted. In addition to our work on ice nucleation, we constructed a photoacoustic spectrometer to measure the absorbance of aerosol particles to study the optical properties of atmospheric aerosol. These measurements will aid in understanding the interactions of aerosol particles with light and the radiative balance of the planet.
Download or read book Physics and Chemistry of Ice written by Werner F. Kuhs and published by Royal Society of Chemistry. This book was released on 2007 with total page 721 pages. Available in PDF, EPUB and Kindle. Book excerpt: Physics and Chemistry of Ice is an authoritative summary of state-of the-art research contributions from the world's leading scientists. A key selection of submissions from to the 11th International Conference on the Physics and Chemistry of Ice, 2006 are presented here with a foreword by Werner F. Kuhs. An invaluable resource, this book provides researchers and professionals with up-to-date coverage on a wide range of areas in ice science including: " Spectroscopic and diffraction studies " Molecular dynamics simulations " Studies of ice mechanics " Quantum mechanical ab initio calculations " Ice and hydrate crystal growth and inhibition studies " Bulk and surface properties of ice and gas hydrates " Snow physics and chemistry This insight into topical aspects of ice research is a key point of reference for physicists, chemists, galciologists, cryo-biologists and professionals working in the fields of ice and hydrogen bonding. The Editor Werner F. Kuhs is a Professor of Crystallography at the University of G÷ttingen, Germany and has a career spanning 25 years of research in the field of water ices and gas hydrates using diffraction methods, neutron and Raman spectroscopy, scanning electron microscopy, atomic force and molecular dynamics simulations. He was the Chair of the 11th International Conference on the Physics and Chemistry of Ice.
Download or read book Microphysics of Clouds and Precipitation written by H.R. Pruppacher and published by Springer Science & Business Media. This book was released on 2010-06-25 with total page 975 pages. Available in PDF, EPUB and Kindle. Book excerpt: Cloud physics has achieved such a voluminous literature over the past few decades that a significant quantitative study of the entire field would prove unwieldy. This book concentrates on one major aspect: cloud microphysics, which involves the processes that lead to the formation of individual cloud and precipitation particles. Common practice has shown that one may distinguish among the following addi tional major aspects: cloud dynamics, which is concerned with the physics respon sible for the macroscopic features of clouds; cloud electricity, which deals with the electrical structure of clouds and the electrification processes of cloud and precipi tation particles; and cloud optics and radar meteorology, which describe the effects of electromagnetic waves interacting with clouds and precipitation. Another field intimately related to cloud physics is atmospheric chemistry, which involves the chemical composition ofthe atmosphere and the life cycle and characteristics of its gaseous and particulate constituents. In view of the natural interdependence of the various aspects of cloud physics, the subject of microphysics cannot be discussed very meaningfully out of context. Therefore, we have found it necessary to touch briefly upon a few simple and basic concepts of cloud dynamics and thermodynamics, and to provide an account of the major characteristics of atmospheric aerosol particles. We have also included a separate chapter on some of the effects of electric fields and charges on the precipitation-forming processes.
Download or read book Carbon in Earth s Interior written by Craig E. Manning and published by John Wiley & Sons. This book was released on 2020-04-03 with total page 373 pages. Available in PDF, EPUB and Kindle. Book excerpt: Carbon in Earth's fluid envelopes - the atmosphere, biosphere, and hydrosphere, plays a fundamental role in our planet's climate system and a central role in biology, the environment, and the economy of earth system. The source and original quantity of carbon in our planet is uncertain, as are the identities and relative importance of early chemical processes associated with planetary differentiation. Numerous lines of evidence point to the early and continuing exchange of substantial carbon between Earth's surface and its interior, including diamonds, carbon-rich mantle-derived magmas, carbonate rocks in subduction zones and springs carrying deeply sourced carbon-bearing gases. Thus, there is little doubt that a substantial amount of carbon resides in our planet's interior. Yet, while we know it must be present, carbon's forms, transformations and movements at conditions relevant to the interiors of Earth and other planets remain uncertain and untapped. Volume highlights include: - Reviews key, general topics, such as carbonate minerals, the deep carbon cycle, and carbon in magmas or fluids - Describes new results at the frontiers of the field with presenting results on carbon in minerals, melts, and fluids at extreme conditions of planetary interiors - Brings together emerging insights into carbon's forms, transformations and movements through study of the dynamics, structure, stability and reactivity of carbon-based natural materials - Reviews emerging new insights into the properties of allied substances that carry carbon, into the rates of chemical and physical transformations, and into the complex interactions between moving fluids, magmas, and rocks to the interiors of Earth and other planets - Spans the various chemical redox states of carbon, from reduced hydrocarbons to zero-valent diamond and graphite to oxidized CO2 and carbonates - Captures and synthesizes the exciting results of recent, focused efforts in an emerging scientific discipline - Reports advances over the last decade that have led to a major leap forward in our understanding of carbon science - Compiles the range of methods that can be tapped tap from the deep carbon community, which includes experimentalists, first principles theorists, thermodynamic modelers and geodynamicists - Represents a reference point for future deep carbon science research Carbon in Planetary Interiors will be a valuable resource for researchers and students who study the Earth's interior. The topics of this volume are interdisciplinary, and therefore will be useful to professionals from a wide variety of fields in the Earth Sciences, such as mineral physics, petrology, geochemistry, experimentalists, first principles theorists, thermodynamics, material science, chemistry, geophysics and geodynamics.
Download or read book A Molecular Dynamics Investigation of Ice Nucleation Induced by Electric Fields written by Jingyi Yan and published by . This book was released on 2014 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Advances in Computer Simulation Studies on Crystal Growth written by Hiroki Nada and published by MDPI. This book was released on 2018-11-16 with total page 207 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book is a printed edition of the Special Issue "Advances in Computer Simulation Studies on Crystal Growth" that was published in Crystals
Download or read book Nucleation of Gas Hydrates written by Nobuo Maeda and published by Springer Nature. This book was released on 2020-08-15 with total page 197 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book introduces readers to experimental techniques of general utility that can be used to practically and reliably determine nucleation rates. It also covers the basics of gas hydrates, phase equilibria, nucleation theory, crystal growth, and interfacial gaseous states. Given its scope, the book will be of interest to graduate students and researchers in the field of hydrate nucleation. The formation of gas hydrates is a first-order phase transition that begins with nucleation. Understanding nucleation is of interest to many working in the chemical and petroleum industry, since nucleation, while beneficial in many chemical processes, is also a concern in terms of flow assurance for oil and natural gas pipelines. A primary difficulty in the investigation of gas hydrate nucleation has been researchers’ inability to determine and compare the nucleation rates of gas hydrates across systems with different scales and levels of complexity, which in turn has limited their ability to study the nucleation process itself. This book introduces readers to experimental techniques that can be used to practically and reliably determine the nucleation rates of gas hydrate systems. It also covers the basics of gas hydrates, phase equilibria, nucleation theory, crystal growth, and interfacial gaseous states. Given its scope, the book will be of interest to graduate students and researchers in the field of hydrate nucleation.
Download or read book Antifreeze Proteins Volume 1 written by Hans Ramløv and published by Springer Nature. This book was released on 2020-06-30 with total page 318 pages. Available in PDF, EPUB and Kindle. Book excerpt: This first volume provides a comprehensive overview on evolutionary, environmental and systematic aspects of antifreeze proteins. It shortly explains the physical properties of ice and further intelligibly describes the biology of the antifreeze proteins in different organisms, and offers a detailed insight into their history of evolution. In addition the book discusses the status of the current knowledge and ongoing research and highlights also those parts, where further investigation needs to be done. Together with the second volume on the biochemistry and molecular biology of antifreeze proteins, this book represents a unique, comprehensive work and a must-have for students and scientists in biochemistry, evolution, physiology and physical chemistry.
Download or read book A Water Activity Based Model of Heterogeneous Ice Nucleation Kinetics for Freezing of Water and Aqueous Solution Droplets written by and published by . This book was released on 2013 with total page 16 pages. Available in PDF, EPUB and Kindle. Book excerpt: Immersion freezing of water and aqueous solutions by particles acting as ice nuclei (IN) is a common process of heterogeneous ice nucleation which occurs in many environments, especially in the atmosphere where it results in the glaciation of clouds. Here we experimentally show, using a variety of IN types suspended in various aqueous solutions, that immersion freezing temperatures and kinetics can be described solely by temperature, T, and solution water activity, aw, which is the ratio of the vapour pressure of the solution and the saturation water vapour pressure under the same conditions and, in equilibrium, equivalent to relative humidity (RH). This allows the freezing point and corresponding heterogeneous ice nucleation rate coefficient, Jhet, to be uniquely expressed by T and aw, a result we term the aw based immersion freezing model (ABIFM). This method is independent of the nature of the solute and accounts for several varying parameters, including cooling rate and IN surface area, while providing a holistic description of immersion freezing and allowing prediction of freezing temperatures, Jhet, frozen fractions, ice particle production rates and numbers. Our findings are based on experimental freezing data collected for various IN surface areas, A, and cooling rates, r, of droplets variously containing marine biogenic material, two soil humic acids, four mineral dusts, and one organic monolayer acting as IN. For all investigated IN types we demonstrate that droplet freezing temperatures increase as A increases. Similarly, droplet freezing temperatures increase as the cooling rate decreases. The log10(Jhet) values for the various IN types derived exclusively by T and aw, provide a complete description of the heterogeneous ice nucleation kinetics. Thus, the ABIFM can be applied over the entire range of T, RH, total particulate surface area, and cloud activation timescales typical of atmospheric conditions. Finally, we demonstrate that ABIFM can be used to derive frozen fractions of droplets and ice particle production for atmospheric models of cirrus and mixed phase cloud conditions.
Download or read book Mixed Phase Clouds written by Constantin Andronache and published by Elsevier. This book was released on 2017-09-28 with total page 302 pages. Available in PDF, EPUB and Kindle. Book excerpt: Mixed-Phase Clouds: Observations and Modeling presents advanced research topics on mixed-phase clouds. As the societal impacts of extreme weather and its forecasting grow, there is a continuous need to refine atmospheric observations, techniques and numerical models. Understanding the role of clouds in the atmosphere is increasingly vital for current applications, such as prediction and prevention of aircraft icing, weather modification, and the assessment of the effects of cloud phase partition in climate models. This book provides the essential information needed to address these problems with a focus on current observations, simulations and applications. Provides in-depth knowledge and simulation of mixed-phase clouds over many regions of Earth, explaining their role in weather and climate Features current research examples and case studies, including those on advanced research methods from authors with experience in both academia and the industry Discusses the latest advances in this subject area, providing the reader with access to best practices for remote sensing and numerical modeling
