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

Bismuth vanadate (BiVO4) is a promising visible-light driven semiconductor photocatalyst with various benefits such as low production cost, low toxicity, high photostability, resistance to photo-corrosion and narrow band gap with a good response to visible-light excite. However, the fast recombination of photoinduced charge carriers restricts their photocatalytic activity. In the past decades, many attempts were adopted to enhance the photocatalytic activity of BiVO4. Significant advances in understanding the fundamental issues and the development of an efficient photocatalyst have been made in current years. In this review, we have provided a comprehensive overview of the latest progress on the morphology control and growth mechanism of BiVO4 micro/nano-structures, doping with metal and non-metal elements and semiconductor coupling along with some highlights in the photodegradation of organic pollutants under visible-light illumination. This review may benefit the researchers and engineers in the arena of material chemistry for designing new BiVO4 based photocatalysts with low production cost and high efficiency.

A review on BiVO4 photocatalyst: Activity enhancement methods for solar photocatalytic applications

High strain piezoelectric ceramics are the state-of-the-art materials for high precision, positioning devices. A comprehensive review of the latest developments of the various types of perovskite piezoelectric ceramic systems is presented herein, with special attention given to three promising families of lead-free perovskite ferroelectrics: the barium titanate, alkaline niobate and bismuth perovskites. Included in this review are details of phase transition behavior, strain enhancement approaches, material reliabilities as well as the status of some promising applications. This current review describes both compositional and structural engineering approaches that are intended to achieve enhanced strain properties in perovskite piezoelectric ceramics. The factors that affect the strain behavior of high-strain perovskite piezoelectric ceramics are addressed. The reliability characteristics of these high-strain ferroelectrics as well as the recent approaches to the long-term electrical, thermal and time-stability enhancement are summarized. Several promising applications of high-strain perovskite materials are introduced, which take advantages of their characteristics; examples include high-energy storage, pyroelectric and electro-caloric effect and luminescent properties.

Progress in high-strain perovskite piezoelectric ceramics

Despite regulation of the reactive oxygen species (ROS) level is an intelligent strategy for cancer therapy, the therapeutic effects of ROS-mediated therapy (including photodynamic therapy (PDT) and chemodynamic therapy (CDT)) are limited by oxygen reliance, inherent flaws of traditional photosensitizers, and strict reaction conditions of effective Fenton reaction. Herein, we reported biocompatible copper ferrite nanospheres (CFNs) with enhanced ROS production under irradiation with a 650 nm laser through direct electron transfer and photoenhanced Fenton reaction and high photothermal conversion efficiency upon exposure to an 808 nm laser, exhibiting a considerable improved synergistic treatment effect. Importantly, by exploiting the properties of O2 generation and glutathione (GSH) depletion of CFNs, CFNs relieve the hypoxia and antioxidant capability of the tumor, achieving photoenhanced CDT and improved PDT. The high relaxivity of 468.06 mM–1 s–1 enables CFNs to act as an outstanding contrast agent for...

All-in-One Theranostic Nanoagent with Enhanced Reactive Oxygen Species Generation and Modulating Tumor Microenvironment Ability for Effective Tumor Eradication

Ionic liquids (ILs) have been widely investigated as novel solvents, electrolytes, and soft functional materials. Nevertheless, the widespread applications of ILs in most cases have been hampered by their liquid state. The confinement of ILs into nanoporous hosts is a simple but versatile strategy to overcome this problem. Nanoconfined ILs constitute a new class of composites with the intrinsic chemistries of ILs and the original functions of solid matrices. The interplay between these two components, particularly the confinement effect and the interactions between ILs and pore walls, further endows ILs with significantly distinct physicochemical properties in the restricted space compared to the corresponding bulk systems. The aim of this article is to provide a comprehensive review of nanoconfined ILs. After a brief introduction of bulk ILs, the synthetic strategies and investigation methods for nanoconfined ILs are documented. The local structure and physicochemical properties of ILs in diverse porous ...

Nanoconfined Ionic Liquids

Fabrication of nanostructured CuO films by electrodeposition and their photocatalytic properties

Controllable fabrication of CuO nanostructure by hydrothermal method and its properties

In order to achieve high performance in visible-light photocatalysis, V4+ and Ce3+ self-doped BiVO4/CeO2 heterostructured nanocomposites with high surface areas were prepared using the templating approach employing mesoporous silica MCM-41 as the hard template. X-ray photoelectron spectroscopy (XPS) spectra have demonstrated the presence of plentiful V4+ and Ce3+ species in the nanocomposites accompanied by the formation of oxygen vacancies. The presence of V4+ species is further identified by the electron spin resonance (ESR) spectrum. Furthermore, the BiVO4 and CeO2 could be affecting each other by arousing the structural changes in the formed nanocomposites. The V4+ and Ce3+ self-doped 0.4BiVO4/0.6CeO2 nanocomposite with the surface area as large as 78.35 m2/g exhibits the highest photocatalytic activity for the rhodamine B (RhB) and methyl orange (MO) degradation and photoelectrochemical performances. The enhanced photocatalytic mechanism is systematically studied via UV–vis diffuse reflectance spectr...

In Situ Synthesis of V4+ and Ce3+ Self-Doped BiVO4/CeO2 Heterostructured Nanocomposites with High Surface Areas and Enhanced Visible-Light Photocatalytic Activity

Dawei Meng

Papers

Fabrication of nanostructured CuO films by electrodeposition and their photocatalytic properties

Controllable fabrication of CuO nanostructure by hydrothermal method and its properties

In Situ Synthesis of V4+ and Ce3+ Self-Doped BiVO4/CeO2 Heterostructured Nanocomposites with High Surface Areas and Enhanced Visible-Light Photocatalytic Activity

Synthesis and enhanced photocatalytic property of feather-like Cd-doped CuO nanostructures by hydrothermal method

Enhanced photocatalytic activity of hierarchically structured BiVO4 oriented along {040} facets with different morphologies