Metalloenzymes preorganize the reaction environment to steer substrate(s) along the required reaction coordinate. Here, we show that phosphine ligands selectively facilitate protonation of binuclear silver hydride cations, [LAg2(H)](+) by optimizing the geometry of the active site. This is a key step in the selective, catalysed extrusion of carbon dioxide from formic acid, HO2CH, with important...

This paper presents a method for interactively rendering complex repetitive scenes such as landscapes, fur, organic tissues, etc. It is an adaptation to Z-buffer of volumetric textures, a ray-traced method, in order to use the power of existing graphics hardware. Our approach consists in slicing a piece of 3D geometry (one repetitive detail of the complex data) into a series of thin layers. A l...

Structures that are 3D printed by an extrusion process have periodic geometrical heterogeneity whose influence on the final stiffness properties is not extensively discussed in existing literature. The objective of this article to quantify effect local lace geometry anisotropy extrusion-based 3d structures. A numerical homogenisation scheme implemented compute equivalent homogeneous Kirchhoff–L...

A new method for the simulation of 2D viscoelastic flow is presented. Numerical stability is obtained by the logarithmic-conformation change of variable, and a fully-implicit pure-streamfunction flow formulation, without use of any artificial diffusion. As opposed to other simulation results, our calculations predict a hydrodynamic instability in the 4:1 contraction geometry at a Weissenberg nu...

This article reviews the infrequently utilized treatment method of forced eruption and how it can serve as an alternative to the sacrifice of the natural root system. Forced eruption can preserve the natural root system and related periodontal architecture, resulting in years of additional service for the patient. It also can maintain adjacent tooth structure while retaining the option for futu...

one of the most important parts of power transmission in automotives is c.v. joint, which consists of four components where exterior bowl is one of them. due to its complexity, and importance in automobile and existence of high stresses, forging process is the only cost effective method of production. hence, the best method of production of this part is forging process. the exterior part of c.v...

During the porthole die extrusion, separated metal streams are welded together in welding chamber. The conditions under which this occurs and integrity of weld seam extrudate impacted by design bridge, including features such as its shape dimensions. In research, commercial finite element method (FEM) software package, DEFORM, was used to run a series simulation experiments order quantitatively...