There is, I think, something ethereal about i —the square root of minus one. I remember first hearing about it at school. It seemed an odd beast at that time—an intruder hovering on the edge of reality.

Usually familiarity dulls this sense of the bizarre, but in the case of i it was the reverse: over the years the sense of its surreal nature intensified. It seemed that it was impossible to write mathematics that described the real world in …

I and i

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

We developed two-step solution-phase reactions to form hybrid materials of Mn3O4 nanoparticles on reduced graphene oxide (RGO) sheets for lithium ion battery applications. Mn3O4 nanoparticles grown selectively on RGO sheets over free particle growth in solution allowed for the electrically insulating Mn3O4 nanoparticles wired up to a current collector through the underlying conducting graphene network. The Mn3O4 nanoparticles formed on RGO show a high specific capacity up to ~900mAh/g near its theoretical capacity with good rate capability and cycling stability, owing to the intimate interactions between the graphene substrates and the Mn3O4 nanoparticles grown atop. The Mn3O4/RGO hybrid could be a promising candidate material for high-capacity, low-cost, and environmentally friendly anode for lithium ion batteries. Our growth-on-graphene approach should offer a new technique for design and synthesis of battery electrodes based on highly insulating materials.

Mn3O4-Graphene Hybrid as a High Capacity Anode Material for Lithium Ion Batteries

In view of the climate changes caused by the continuously rising levels of atmospheric CO2 , advanced technologies associated with CO2 conversion are highly desirable. In recent decades, electrochemical reduction of CO2 has been extensively studied since it can reduce CO2 to value-added chemicals and fuels. Considering the sluggish reaction kinetics of the CO2 molecule, efficient and robust electrocatalysts are required to promote this conversion reaction. Here, recent progress and opportunities in inorganic heterogeneous electrocatalysts for CO2 reduction are discussed, from the viewpoint of both experimental and computational aspects. Based on elemental composition, the inorganic catalysts presented here are classified into four groups: metals, transition-metal oxides, transition-metal chalcogenides, and carbon-based materials. However, despite encouraging accomplishments made in this area, substantial advances in CO2 electrolysis are still needed to meet the criteria for practical applications. Therefore, in the last part, several promising strategies, including surface engineering, chemical modification, nanostructured catalysts, and composite materials, are proposed to facilitate the future development of CO2 electroreduction.

Recent Advances in Inorganic Heterogeneous Electrocatalysts for Reduction of Carbon Dioxide

Recent advancements in supercapacitor technology

Highly sensitive enzyme-less electrochemical glucose sensor based on copper oxide/multi-walled carbon nanotube (MWCNT) composite (CuO-MWCNTs) modified glassy carbon electrode (GCE) was prepared by co-precipitation method. The as-prepared nanocomposites were characterized by field emission scanning electron microscope (FE-SEM), Raman spectroscopy, Fourier transform infrared spectroscopy and electrochemical analyses. The electrochemical results of cyclic voltammetry (CV) and chronoamperometry demonstrated that the CuO-MWCNTs/Nf/GCE showed high electrocatalytic activity than the copper oxide nanoleaves (CuO-Nplts) modified electrode toward glucose. The modified electrode showed enhanced electrocatalytic behaviour towards glucose in alkaline medium. The non-enzymatic glucose sensor based on CuO-MWCNTs/Nf/GCE showed the highest sensitivity of 1038.6 µA mM−1cm−2 with the lowest detection limit of 0.1 µM (signal/noise ratio (S/N) of 3) under optimal experimental conditions. The fabricated sensor showed good accuracy, reproducibility and stability. The sensor was highly selective to detect the glucose in the presence of other common interfering species like ascorbic acid, uric acid and dopamine. The modified electrode was used to determine the dopamine in neutral medium.

CuO-MWCNTS for Enzyme-Less Electrochemical Detection of Glucose and Dopamine

Solvothermal Preparation of Graphene Supported Mn Ferrites and its Photocatalytic Activity

https://pubs.acs.org/doi/pdf/10.1021/acs.chemmater.0c02211

Andrews Nirmala Grace

Papers

CuO-MWCNTS for Enzyme-Less Electrochemical Detection of Glucose and Dopamine

Solvothermal Preparation of Graphene Supported Mn Ferrites and its Photocatalytic Activity

Checking in with Women Materials Scientists During a Global Pandemic: May 2020

Poly(3,4-ethylenedioxythiophene) decorated MXene as an alternative counter electrode for dye-sensitized solar cells

Non-Enzymatic Electrochemical Detection of Glucose Using Graphene/Copper Oxide Nanocomposites