Computational Fluid-Structure Interaction: Methods and Applicationstakes the reader from the fundamentals of computational fluid and solid mechanics to the state-of-the-art in computational FSI ...methods, special FSI techniques, and solution of real-world problems. Leading experts in the field present the material using a unique approach that combines advanced methods, special techniques, and challenging applications.This book begins with the differential equations governing the fluid and solid mechanics, coupling conditions at the fluid–solid interface, and the basics of the finite element method. It continues with the ALE and space–time FSI methods, spatial discretization and time integration strategies for the coupled FSI equations, solution techniques for the fully-discretized coupled equations, and advanced FSI and space–time methods. It ends with special FSI techniques targeting cardiovascular FSI, parachute FSI, and wind-turbine aerodynamics and FSI.Key features:First book to address the state-of-the-art in computational FSICombines the fundamentals of computational fluid and solid mechanics, the state-of-the-art in FSI methods, and special FSI techniques targeting challenging classes of real-world problemsCovers modern computational mechanics techniques, including stabilized, variational multiscale, and space–time methods, isogeometric analysis, and advanced FSI coupling methodsIs in full color, with diagrams illustrating the fundamental concepts and advanced methods and with insightful visualization illustrating the complexities of the problems that can be solved with the FSI methods covered in the book.Authors are award winning, leading global experts in computational FSI, who are known forsolving some of the most challenging FSI problemsComputational Fluid-Structure Interaction: Methods and Applicationsis a comprehensive reference for researchers and practicing engineers who would like to advance their existing knowledge on these subjects. It is also an ideal text for graduate and senior-level undergraduate courses in computational fluid mechanics and computational FSI.
Lithium sulfur batteries have brought significant advancement to the current state-of-art battery technologies because of their high theoretical specific energy, but their wide-scale implementation ...has been impeded by a series of challenges, especially the dissolution of intermediate polysulfides species into the electrolyte. Conductive polymers in combination with nanostructured sulfur have attracted great interest as promising matrices for the confinement of lithium polysulfides. However, the roles of different conductive polymers on the electrochemical performances of sulfur electrode remain elusive and poorly understood due to the vastly different structural configurations of conductive polymer-sulfur composites employed in previous studies. In this work, we systematically investigate the influence of different conductive polymers on the sulfur cathode based on conductive polymer-coated hollow sulfur nanospheres with high uniformity. Three of the most well-known conductive polymers, polyaniline (PANI), polypyrrole (PPY), and poly(3,4-ethylenedioxythiophene) (PEDOT), were coated, respectively, onto monodisperse hollow sulfur nanopsheres through a facile, versatile, and scalable polymerization process. The sulfur cathodes made from these well-defined sulfur nanoparticles act as ideal platforms to study and compare how coating thickness, chemical bonding, and the conductivity of the polymers affected the sulfur cathode performances from both experimental observations and theoretical simulations. We found that the capability of these three polymers in improving long-term cycling stability and high-rate performance of the sulfur cathode decreased in the order of PEDOT > PPY > PANI. High specific capacities and excellent cycle life were demonstrated for sulfur cathodes made from these conductive polymer-coated hollow sulfur nanospheres.
Doping is a widely applied technological process in materials science that involves incorporating atoms or ions of appropriate elements into host lattices to yield hybrid materials with desirable ...properties and functions. For nanocrystalline materials, doping is of fundamental importance in stabilizing a specific crystallographic phase, modifying electronic properties, modulating magnetism as well as tuning emission properties. Here we describe a material system in which doping influences the growth process to give simultaneous control over the crystallographic phase, size and optical emission properties of the resulting nanocrystals. We show that NaYF4 nanocrystals can be rationally tuned in size (down to ten nanometres), phase (cubic or hexagonal) and upconversion emission colour (green to blue) through use of trivalent lanthanide dopant ions introduced at precisely defined concentrations. We use first-principles calculations to confirm that the influence of lanthanide doping on crystal phase and size arises from a strong dependence on the size and dipole polarizability of the substitutional dopant ion. Our results suggest that the doping-induced structural and size transition, demonstrated here in NaYF4 upconversion nanocrystals, could be extended to other lanthanide-doped nanocrystal systems for applications ranging from luminescent biological labels to volumetric three-dimensional displays.
We discovered for the first time that light can twist metal to control the chirality of metal nanostructures (hereafter, chiral metal nanoneedles). The helicity of optical vortices is transferred to ...the constituent elements of the irradiated material (mostly melted material), resulting in the formation of chiral metal nanoneedles. The chirality of these nanoneedles could be controlled by just changing the sign of the helicity of the optical vortex. The tip curvature of these chiral nanoneedles was measured to be <40 nm, which is less than 1/25th of the laser wavelength (1064 nm). Such chiral metal nanoneedles will enable us to selectively distinguish the chirality and optical activity of molecules and chemical composites on a nanoscale and they will provide chiral selectivity for nanoscale imaging systems (e.g., atomic force microscopes), chemical reactions on plasmonic nanostructures, and planar metamaterials.
This handbook and ready reference presents a combination of statistical, information-theoretic, and data analysis methods to meet the challenge of designing empirical models involving molecular ...descriptors within bioinformatics. The topics range from investigating information processing in chemical and biological networks to studying statistical and information-theoretic techniques for analyzing chemical structures to employing data analysis and machine learning techniques for QSAR/QSPR. The high-profile international author and editor team ensures excellent coverage of the topic, making this a must-have for everyone working in chemoinformatics and structure-oriented drug design.
Decellularized matrices are valuable scaffolds for engineering functional cardiac patches for treating myocardial infarction. However, the lack of quick and efficient electrical coupling between ...adjacent cells may jeopardize the success of the treatment. To address this issue, we have deposited gold nanoparticles on fibrous decellularized omental matrices and investigated their morphology, conductivity, and degradation. We have shown that cardiac cells engineered within the hybrid scaffolds exhibited elongated and aligned morphology, massive striation, and organized connexin 43 electrical coupling proteins. Finally, we have shown that the hybrid patches demonstrated superior function as compared to pristine patches, including a stronger contraction force, lower excitation threshold, and faster calcium transients.
In this work, we propose a nanoscale three-dimensional (3D) Si phononic crystal (PnC) with spherical pores, which can reduce the thermal conductivity of bulk Si by a factor up to 10,000 times at room ...temperature. Thermal conductivity of Si PnCs depends on the porosity, for example, the thermal conductivity of Si PnCs with porosity 50% is 300 times smaller than that of bulk Si. The phonon participation ratio spectra demonstrate that more phonons are localized as the porosity increases. The thermal conductivity is insensitive to the temperature changes from room temperature to 1100 K. The extreme-low thermal conductivity could lead to a larger value of ZT than unity as the periodic structure affects very little the electric conductivity.
Understanding structure-activity relationships (SARs) for a given set of molecules allows one to rationally explore chemical space and develop a chemical series optimizing multiple physicochemical ...and biological properties simultaneously, for instance, improving potency, reducing toxicity, and ensuring sufficient bioavailability. In silico methods allow rapid and efficient characterization of SARs and facilitate building a variety of models to capture and encode one or more SARs, which can then be used to predict activities for new molecules. By coupling these methods with in silico modifications of structures, one can easily prioritize large screening decks or even generate new compounds de novo and ascertain whether they belong to the SAR being studied. Computational methods can provide a guide for the experienced user by integrating and summarizing large amounts of preexisting data to suggest useful structural modifications. This chapter highlights the different types of SAR modeling methods and how they support the task of exploring chemical space to elucidate and optimize SARs in a drug discovery setting. In addition to considering modeling algorithms, I briefly discuss how to use databases as a source of SAR data to inform and enhance the exploration of SAR trends. I also review common modeling techniques that are used to encode SARs, recent work in the area of structure-activity landscapes, the role of SAR databases, and alternative approaches to exploring SAR data that do not involve explicit model development.
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