Abrasion Wear Resistance of Precipitation-Hardened Al-Zn-Mg Alloy.

The heat treatment of aluminum alloys is very important in industries where low weight in combination with high wear resistance, good strength, and hardness are important. However, depending on their chemical composition, aluminum alloys are subjected to different mechanical and thermal treatments to achieve the most favorable properties. In this study, an Al-Zn-Mg alloy was heat-treated including solution annealing at 490 °C for 1 h with subsequent artificial aging at 130, 160, and 190 °C for 1, 5, and 9 h.

The Effect of Foaming Agents on the Thermal Behavior of Aluminum Precursors.

Various foaming agents can be used to achieve foaming of the precursors obtained by using the powder metallurgy method. However, the thermal behavior of pure aluminum precursors with different foaming agents has been studied very little in recent times. For the production of aluminum foams with closed cells, 1 wt.

Functional hydration and conformational gating of proton uptake in cytochrome c oxidase.

Cytochrome c oxidase couples the reduction of dioxygen to proton pumping against an electrochemical gradient. The D-channel, a 25-A-long cavity, provides the principal pathway for the uptake of chemical and pumped protons. A water chain is thought to mediate the relay of protons via a Grotthuss mechanism through the D-channel, but it is interrupted at N139 in all available crystallographic structures.

Calculation of absolute protein-ligand binding free energy using distributed replica sampling.

Distributed replica sampling [T. Rodinger et al., J.

Distributed Replica Sampling.

We present a simple and general scheme for efficient Boltzmann sampling of conformational space by computer simulation. Multiple replicas of the system differing in temperature T or reaction coordinate λ are simulated independently. In addition, occasional stochastic moves of individual replicas in T or λ space are considered one at a time on the basis of a generalized Hamiltonian containing an extra potential energy term or bias that depends on the distribution of all replicas.