Deforming Diamond

For materials science, diamond crystals are almost unrivaled for hardness and a range of other properties. Yet, when simply abstracting the carbon bonding structure as a geometric bar-and-joint periodic framework, it is far from rigid. We study the geometric deformations of this type of framework in arbitrary dimension d, with particular regard to the volume variation of a unit cell

Влияние предварительного пластического деформирования на шероховатость поверхности титанового сплава Ti–Si после алмазной доводки

Research technique and results are represented for a study of surface roughness and structure at diamond lapping of titanic alloy with system Ti–Si. Because of structure heterogeneity it is impossible to receive stable surface quality after diamond processing on textolite lap. Preliminary surface plastic deforming is added to decrease surface roughness of titanic alloy

Tractable Simulation of Error Correction with Honest Approximations to Realistic Fault Models

In previous work, we proposed a method for leveraging efficient classical simulation algorithms to aid in the analysis of large-scale fault tolerant circuits implemented on hypothetical quantum information processors. Here, we extend those results by numerically studying the efficacy of this proposal as a tool for understanding the performance of an error-correction gadget implemented with fault models derived from physical simulations. Our approach is to approximate the arbitrary error maps that arise from realistic physical models with errors that are amenable to a particular classical simulation algorithm in an "honest" way; that is, such that we do not underestimate the faults introduced by our physical models. In all cases, our approximations provide an "honest representation" of the performance of the circuit composed of the original errors. This numerical evidence supports the use of our method as a way to understand the feasibility of an implementation of quantum information processing given a characterization of the underlying physical processes in experimentally accessible examples.Comment: 34 pages, 9 tables, 4 figure

The use of deforming broaching for enhancing the efficiency of cutter chisels

Purpose. To determine the potential of deforming broaching for the improvement of efficiency of cutter chisels in the mining industry. Methodology. The study of the application of the technological process of deforming broaching was carried out based on the experimental research into conditions of assembly of press couplings corresponding to cutting rock-destroying tools, the working surface of which is reinforced with solid-alloy inserts. Findings. Based on the conducted research, a new process of assembling the crowns of cutter chisels with the use of deforming broaching was developed. Originality. It was determined that the range of angles of inclination of generatrix of the working cone of the deforming element and the roll-treading lip of the insert, which are necessary for efficient machining and pressing in crowns of cutters, is 4–16°. It was proven that the “solid alloy-steel” press couplings for cutter chisels will have the maximum bearing capacity at total tension a/d0 ≤ 3 %. It was found that it is necessary to foresee the following distribution of tensions: to perform 2 % of deformation by preliminary deforming broaching, and 1 % ‒ by pressing in an insert Practical value. The use of deforming broaching makes it possible to increase the strength of fastening the inserts of cutter chisels by 2 times, to reduce specific consumption of the tool by 4.4 times, and to increase the average drilling rate by 4 times

Unification of M- and F- Theory Calabi-Yau Fourfold Vacua

We consider splitting type phase transitions between Calabi-Yau fourfolds. These transitions generalize previously known types of conifold transitions between threefolds. Similar to conifold configurations the singular varieties mediating the transitions between fourfolds connect moduli spaces of different dimensions, describing ground states in M- and F-theory with different numbers of massless modes as well as different numbers of cycles to wrap various p-branes around. The web of Calabi-Yau fourfolds obtained in this way contains the class of all complete intersection manifolds embedded in products of ordinary projective spaces, but extends also to weighted configurations. It follows from this that for some of the fourfold transitions vacua with vanishing superpotential are connected to ground states with nonzero superpotential.Comment: plain TeX, 22p

Инструмент из АКТМ для обработки деталей из титановых сплавов обкатыванием

The new technology of preparation of blank from a diamond composite heat-resistant material (АКТМ) in the form of a sphere is described. Results of tests of working element of rolling device from АКТМ at machining of titanic alloy ВТ1-0 are presented. Dependence of a roughness of a machined surface on technological modes rolling is investigated. It is established, that the resistance of wear of a deforming element from АКТМ at least 10 times more the steel