Three parallel algorithms for classical molecular dynamics are presented. The first assigns each processor a fixed subset of atoms; the second assigns each a fixed subset of inter-atomic forces to compute; the third assigns each a fixed spatial region. The algorithms are suitable for molecular dynamics models which can be difficult to parallelize efficiently—those with short-range forces where the neighbors of each atom change rapidly. They can be implemented on any distributed-memory parallel machine which allows for message-passing of data between independently executing processors. The algorithms are tested on a standard Lennard-Jones benchmark problem for system sizes ranging from 500 to 100,000,000 atoms on several parallel supercomputers--the nCUBE 2, Intel iPSC/860 and Paragon, and Cray T3D. Comparing the results to the fastest reported vectorized Cray Y-MP and C90 algorithm shows that the current generation of parallel machines is competitive with conventional vector supercomputers even for small problems. For large problems, the spatial algorithm achieves parallel efficiencies of 90% and a 1840-node Intel Paragon performs up to 165 faster than a single Cray C9O processor. Trade-offs between the three algorithms and guidelines for adapting them to more complex molecular dynamics simulations are also discussed.

Fast parallel algorithms for short-range molecular dynamics

New materials hold the key to fundamental advances in energy conversion and storage, both of which are vital in order to meet the challenge of global warming and the finite nature of fossil fuels. Nanomaterials in particular offer unique properties or combinations of properties as electrodes and electrolytes in a range of energy devices. This review describes some recent developments in the discovery of nanoelectrolytes and nanoelectrodes for lithium batteries, fuel cells and supercapacitors. The advantages and disadvantages of the nanoscale in materials design for such devices are highlighted.

https://img62.chem17.com/1/20140715/635410323829886334962.pdf

Nanostructured materials for advanced energy conversion and storage devices

https://www.bc.edu/content/dam/files/schools/cas_sites/physics/pdf/Ren/p85.pdf

Advances in the science and technology of carbon nanotubes and their composites: a review

Department of Materials Science, University of Patras, 26504 Rio Patras, Greece, Theoretical and Physical Chemistry Institute, National Hellenic Research Foundation, 48 Vass. Constantinou Avenue, 116 35 Athens, Greece, Institut de Biologie Moleculaire et Cellulaire, UPR9021 CNRS, Immunologie et Chimie Therapeutiques, 67084 Strasbourg, France, and Dipartimento di Scienze Farmaceutiche, Universita di Trieste, Piazzale Europa 1, 34127 Trieste, Italy

Chemistry of Carbon Nanotubes

Small but strong: A review of the mechanical properties of carbon nanotube–polymer composites

Carbon Nanotube Sponges

www.MaterialsViews.com C O M Graphene-On-Silicon Schottky Junction Solar Cells M U N I By Xinming Li , Hongwei Zhu , * Kunlin Wang , * Anyuan Cao , Jinquan Wei , Chunyan Li , Yi Jia , Zhen Li , Xiao Li , and Dehai Wu C A IO N Graphene, a single atomic layer of carbon hexagons, has stimulated a lot of research interest owing to its unique structure and fascinating properties. [ 1 ] Graphene has been produced in the form of ultrathin sheets consisting of one or a few atomic layers by chemical vapor deposition (CVD) [ 2–4 ] or solution processing [ 5 , 6 ] and can be transferred to various substrates. The two-dimensionality and structural fl atness make graphene sheets ideal candidates for thin-fi lm devices and combination with other semiconductor materials such as silicon. These fi lms typically show sheet resistances on the order of several hundred ohm per square at about 80% optical transparency. [ 7 ] With modifi cation on the electronic properties and improvement of processing techniques, graphene fi lms show potential for use in conductive, fl exible electrodes, as an alternative for indium tin oxide (ITO). Graphene applications are just starting, and current investigations are on a number of areas such as fi llers for composites, nanoelectronics, and transparent electrodes. [ 8 ] For applications related to solar cells, graphene microsheets were dispersed into conjugated polymers to improve exciton dissociation and charge transport. [ 9–11 ] Also, solution-processed thin fi lms were used as conductive and transparent electrodes for organic [ 12 ] and dyesensitized [ 13 ] solar cells, although the cell effi ciency is still lower than those with ITO and fl uorine tin oxide (FTO) electrodes. Compared with carbon nanotube fi lms that have been extensively studied, graphene fi lms may have several advantages. A continuous single-layer graphene fi lm could retain high conductivity at very low (atomic) thickness, and avoid contact resistance that occurs in a carbon nanotube fi lm between interconnected nanotube bundles. In addition, graphene fi lms have minimum porosity and, in small areas, can provide an extremely fl at surface for molecule assembly and device integration. There are many opportunities in utilizing distinct properties of graphene and exploring novel applications. Bulk heterojunction structures based on carbon materials have attracted a great deal of interest for both scientifi c fundamentals and potential applications in various new optoelectronic devices,

Graphene‐On‐Silicon Schottky Junction Solar Cells

Sensing strain of soft materials in small scale has attracted increasing attention. In this work, graphene woven fabrics (GWFs) are explored for highly sensitive sensing. A flexible and wearable strain sensor is assembled by adhering the GWFs on polymer and medical tape composite film. The sensor exhibits the following features: ultra-light, relatively good sensitivity, high reversibility, superior physical robustness, easy fabrication, ease to follow human skin deformation, and so on. Some weak human motions are chosen to test the notable resistance change, including hand clenching, phonation, expression change, blink, breath, and pulse. Because of the distinctive features of high sensitivity and reversible extensibility, the GWFs based piezoresistive sensors have wide potential applications in fields of the displays, robotics, fatigue detection, body monitoring, and so forth.

Dehai Wu

Papers

Carbon Nanotube Sponges

Graphene‐On‐Silicon Schottky Junction Solar Cells

Wearable and Highly Sensitive Graphene Strain Sensors for Human Motion Monitoring

Competitive adsorption of Pb2+, Cu2+ and Cd2+ ions from aqueous solutions by multiwalled carbon nanotubes

Adsorption of cadmium(II) from aqueous solution by surface oxidized carbon nanotubes