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

Synthesis and analysis of Mo2N as efficient counter electrodes for dye sensitized solar cells

Nanocellulose-based aerogel electrodes for supercapacitors: A review.

Amine-based postcombustion CO2 capture technology has a great potential to control CO2 emissions but is expensive because a huge amount of thermal energy is required for solvent regeneration due to...

Catalytic Characteristics of Metal Catalysts and NitrateSalt of a Tripodal Ligandin a Basic Medium for Postcombustion CO 2 Capture Process

Recent investigations have demonstrated that nickel ferrite nanoparticles and their derivatives have toxicity effects on bacterial cells. In this study, we have prepared nickel ferrite nanoparticles (Ni/NiFe2O4) and nickel/nickel ferrite graphene oxide (Ni/NiFe2O4–GO) nanocomposite and evaluated their toxic effects on E. coli cells ATCC 25922. The prepared nanomaterials were characterized using X-ray diffraction, Raman spectroscopy, scanning electron microscopy, transmission electron microscopy, and vibrating sample magnetometry techniques. The toxicity was evaluated using variations in cell viability, cell morphology, protein degradation, and oxidative stress. Ni/NiFe2O4–GO nanocomposites likewise prompt oxidative stress proved by the age of reactive oxygen species (ROS) and exhaustion of antioxidant glutathione. This is the first report indicating that Ni/NiFe2O4–GO nanocomposite-initiated cell death in E. coli through ROS age and oxidative stress.

https://www.repository.cam.ac.uk/bitstream/1810/342097/2/article.pdf

Effect of the Graphene- Ni/NiFe2O4 Composite on Bacterial Inhibition Mediated by Protein Degradation

The present work reports the synthesis of biomass derived activated carbon and its electrochemical behaviour in different electrolytes. Ricinus communis shell (RCS) was used as a raw material in this study for the synthesis of activated carbon (AC) following a high-temperature activation procedure using potassium hydroxide as the activating agent. The physical and structural characterization of the prepared Ricinus communis shell-derived activated carbon (RCS-AC) was carried by Brunauer-Emmett-Teller analysis, X-ray diffraction analysis, Fourier Transform Infrared Spectroscopy, Raman Spectroscopy and Scanning Electron Microscopy. The synthesized AC was electrochemically characterized using various techniques such as Cyclic voltammetry (CV), galvanostatic charge–discharge (GCD) tests, and Electrochemical impedance spectroscopy (EIS) measurements in different aqueous electrolytes (KOH, H2SO4, and Na2SO4). The results show that the double layer properties of the RCS-AC material in different electrolytes are distinct. In specific, the working electrode tested in 3 M KOH showed excellent electrochemical performance. It demonstrated a specific capacitance of 137 F g−1 (at 1 A g−1 in 3 M KOH) and exhibited high energy and power densities of 18.2 W hkg−1 and 663.4 W kg−1, respectively. The observed capacitance in 3 M KOH remains stable with 97.2% even after 5000 continuous charge and discharge cycles, indicating long-term stability. The study confirmed that the synthesized RCS-derived activated carbon (RCS-AC) exhibits good stability and physicochemical characteristics, making them commercially promising and appropriate for energy storage applications.

/pdf/investigation-of-different-aqueous-electrolytes-for-biomass-1eesybt6.pdf

Andrews Nirmala Grace

Papers

Synthesis and analysis of Mo2N as efficient counter electrodes for dye sensitized solar cells

Nanocellulose-based aerogel electrodes for supercapacitors: A review.

Catalytic Characteristics of Metal Catalysts and NitrateSalt of a Tripodal Ligandin a Basic Medium for Postcombustion CO 2 Capture Process

Effect of the Graphene- Ni/NiFe2O4 Composite on Bacterial Inhibition Mediated by Protein Degradation

Investigation of Different Aqueous Electrolytes for Biomass-Derived Activated Carbon-Based Supercapacitors