Methods of estimation mechanical stress concentrations by conducting a computer experiment on models welds with defects having zones increased concentration in the form non-welding root weld are considered. The paper notes that full-scale study state determination coefficients equipment itself is difficult due to duration development degradation processes, wear and aging, therefore, their condu...

An effective diversion technique is a crucial component in all acid stimulation jobs, which allows us to achieve full zonal coverage and thereby the treatment objectives. In process of acidizing heterogeneous formations, it necessary change direction fluid target interval, i.e., interval with low permeability, ensure an even distribution pumped fluids throughout formation. This because due diff...

The chemical step of Shikimate Kinase Helicobacter pylori, involving the transfer a phosphoryl group, has been studied by using quantum mechanical and molecular (QM/MM) methods. Understanding mechanism this step, present in bacteria other microorganisms but absent humans, can lead to development novel drugs for treatment common diseases caused those pathogenic organisms. Different mechanisms in...

the fracture resistance of all-ceramic restorations is one of the major concerns in clinical applications of these materials. before initiating a time-consuming and costly clinical investigation, an in vitro study can help to estimate the in vivo usability of a new dental material. mechanical properties of all-ceramic materials are frequently evaluated to predict their clinical performance. sin...

ion reaction is a hydroxo intermediate and a radical. Therefore, the obtained TS geometry is reasonable. In this view, the H atom at the active site should be closer to O atom than to the C atom. Inspection of the spin density of the RS and TS shows that there Figure 3-8. Visualization of spin densities in TS