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The Impact of Nanosciences and Biochemistry 2. Computational 1. The Changing Landscape of Human Chemistry, Wright State University, Dayton, OH, 2 Performance – The Impact of Nanosciences United States; Department of Mechanical and and Biochemistry Materials Engineering, Wright State University, Dayton, OH, United States; 3Department of Physics, Morley O. Stone. 711th Human Performance Wing, Wright State University, Dayton, OH, United States. Air Force Research Laboratory, Wright-Patterson AFB, OH, United States. The potential application of silicene as a hydrogen storage material is studied by computational In all human endeavors, there is a desire to push the modeling using both first principles calculations and limits of human performance – operations within the classical grand canonical Monte Carlo simulations. Air Force are no exception. From aviation to ground The energetics of the adsorption of hydrogen atoms operations, traditional stressors such as fatigue are on silicene are investigated by DFT calculations. In being compounded by the need to process ever- addition, classical simulations were carried out to increasing amounts of information. This deluge of study the physisorption of molecular hydrogen in a information caused by sensor and bandwidth slit-pore model, constructed using two silicene layers, proliferation makes human-intensive operations, such and whose slit-pore size is varied by changing the as decision making, increasingly complicated. interlayer separation. Traditional approaches to alleviate this problem have relied upon increases in manpower (the 4. Interfacial Friction and Sliding in “brainpower”) to sift, prioritize, and act upon this Amorphous Carbon/Nanotube mountain of information. Increasingly, the Nanocomposites Department of Defense and the Air Force are realizing that this solution is untenable. Within the Zhenhai Xia, Jianbing Niu. Department of Human Performance Wing, we realize that advances Mechanical Engineering, The University of Akron, in the biosciences, e.g., neuroscience, and Akron, OH, United States. nanoscience and engineering, e.g., nanoparticle Amorphous carbon matrix nanocomposites assays, are keys to pushing human capacity past reinforced with nanoscale reinforcement such as traditionally accepted limitations. This talk will carbon nanotubes (CNTs) and nano-particles are examine this frontier and outline efforts to reach promising as next generation super-tough and wear novel, multi-disciplinary approaches to redefine resistant coatings. The strength and toughness human performance. properties of these composites are determined by the interface between reinforcement and amorphous- 2. Computational Research for Aerospace phases. Here, interfacial sliding and friction in Materials Development CNT/amorphous carbon composites are analyzed Barry L. Farmer. Materials and Manufacturing using molecular dynamics simulations. We Directorate, Air Force Research Laboratory, Wright- investigate pullout in a nanoscale composite using a Patterson AFB, OH, United States. unit cell composed of one carbon nanotube or a nanofiber and surrounding amorphous carbon matrix The AFRL Materials and Manufacturing Directorate with a certain degree of sp2/sp3 interfacial bonding. utilizes a broad spectrum of computational tools to The nanotubes full of amorphous carbon as discover, develop, understand, and predict the nanofibers were compared with the tube properties and behavior of a wide range of materials configurations. The results show that the interfacial of interest for aerospace applications. These include bonding break and formation play a key role in both hard and soft materials for structural, sensing, interfacial friction. In the case of no chemical optical, thermal, and other applications. An overview bonding formation at the interface, the nanoscale of the types of computational tools that are being roughness determines interfacial friction and it is used and the types of computational chemistry and found that the frictional behavior can be described by materials research that is being conducted will be a molecular friction law. provided through brief summaries of recent and current research projects. 5. Aspects of Multi-Scale Modeling: Calculations of Optical Properties at the 3. Hydrogen Sorption in a Slit-Pore Model of Nano-Scale Silicon Nanosheets Paul N. Day, Kiet A. Nguyen, Jinsong Duan, Ruth Rachel S. Aga,1 Kristy Wickman,1 Amir A. Pachter. Materials & Manufacturing Directorate, Air Farajian,2 Lok C. Lew Yan Voon.3 1Department of Force Research Laboratory, Wright-Patterson Air developments in the simulation and informatics Force Base, Ohio, United States. methodologies that make the implementation of such approaches a practical reality in both academic and The need for multi-scale modeling is evident in the industrial contexts. prediction of optical properties unique to materials at the nano-scale, which are used in a multitude of applications. In our continuing interest in calculating 7. Probing the Conformational Transition multi-photon absorption for molecular and potentially Mechanism of ClpY by Using Molecular nanomaterials, including nanoclusters and hybrid Dynamics Simulations nanomaterials, we outline limitations from quantum- Huan Wang, Manori Jayasinghe, George Stan. to-continuum modeling, which can be addressed by Department of Chemistry, University of Cincinnati, sequential, combined, and concurrent methods. As an Cincinnati, Oh, United States. example, calculation of spectra of gold nanoclusters will be described, while for nanomaterials at a Clp ATPases are bacterial AAA+ motors which use relatively larger nano-scale, effects of various ATP-dependent conformational transitions to effect parameters on the optical properties of a molecular substrate protein (SP) degradation and emitter nearby gold nanorods will be reported. In this disaggregation. context, multi-scale issues encountered in modeling Structurally, Clp ATPases are ring-shaped homo- weak interactions at a molecule—plasmonic hexamers with a dynamic central channel. nanostructure interface will be discussed. Diaphragm-forming loops, located in the central channel, are suggested to promote the unfoldase and 6. The Role of Simulation and Informatics in translocase actions through repetitive pulling of the the Electronic Laboratory Environment SP. We use molecular dynamics simulations to elucidate the collaboration between subunits and Michael J. Doyle, George Fitzgerald. Accelrys Inc., between the central channel loops during the San Diego, CA, United States. sequential allosteric motions. Our focus is on ClpY, For many years, virtual chemistry and simulation has the best structurally characterized Clp ATPase. been a key decission making step in the design of Conformational transitions between open and close news systems, from catalysts through polymers to states of ClpY are modeled by using the Targeted advanced composites and nanofibers. With the advent Molecular Dynamics (TMD) simulation method, in of modern high performance ciomputing this which a holonomic constraint is employed to reduce capability has become more ubiquitious, and now the RMSD from the target by a preset value at each stands poised to deliver on the vision of pattern based molecular dynamics step. The trajectory of the decission making in materials design and selection. transition was simulated by using langevin dynamics The data source agnostic perspective of modern high and implicit solvent model (EEF1). We find that throughput materials development and informatics, single-subunit conformational transitions elicit a considers simulation and experimental data as both strong response within the adjacent subunit nearest to valid feeds of information into this decission matrix. the active ATP binding site.Channel loops associated with these coupled subunits also interact strongly, which suggests the chiral handing of the SP within the pore. These results are in accord with experiments that indicate ordered sequential allostery of the Clp ATPase ring. 8. Applied Metamaterials Augustine M. Urbas, Katie Thorp. Materials and Manufacturing Directorate, Air Force Resaerch Lab, Dayton, OH, United States. Metamaterials redefine the fundamental properties of systems by creating artificial, meso-scale meta-atoms which dictate the system response to external fields. These meta-atoms and their mutual interactions can yield property sets that natural materials are not The talk will cover recent reductions to proof of these capable of and tailor materials properties to specific concepts as well as discuss new algoriuthmic needs. The Air Force Research Lab has launched a coherent effort to identify the range of properties transfer cascade among the energy level of the donor accessible by metamaterials systems in an effort to and acceptors, leading to the generation of high spin map out the application potential of the emerging and states. Ability of amphiphilic C60-(antenna) to dynamic research area. As examples, researchers undergo molecular self-assembly forming bilayer have proposed that materials with negative effective vesicle structures may also facilitate our control in refractive indices that are closely matched to free the alignment of fullerene cage molecules. space and materials with values of epsilon or mu near Preliminary investigation on intrinsic and zero could be built with suitably engineered meta- photoinduced magnetic effects of EF-6MCn and its systems. The utility of these composite materials in complex derivatives using the measurements of dc ultra-compact antennas and signal coupling and
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