2,724 research outputs found
Work hardening behavior in a steel with multiple TRIP mechanisms
Transformation induced plasticity (TRIP) behavior was studied in steel with
composition Fe-0.07C-2.85Si-15.3Mn-2.4Al-0.017N that exhibited two TRIP
mechanisms. The initial microstructure consisted of both {\epsilon}- and
{\alpha}-martensites with 27% retained austenite. TRIP behavior in the first 5%
strain was predominately austenite transforming to {\epsilon}-martensite (Stage
I), but upon saturation of Stage I, the {\epsilon}-martensite transformed to
{\alpha}-martensite (Stage II). Alloy segregation also affected the TRIP
behavior with alloy rich regions producing TRIP just prior to necking. This
behavior was explained by first principle calculations that revealed aluminum
significantly affected the stacking fault energy in Fe-Mn-Al-C steels by
decreasing the unstable stacking fault energy and promoting easy nucleation of
{\epsilon}-martensite. The addition of aluminum also raised the intrinsic
stacking fault energy and caused the {\epsilon}-martensite to be unstable and
transform to {\alpha}-martensite under further deformation. The two stage TRIP
behavior produced a high strain hardening exponent of 1.4 and led to ultimate
tensile strength of 1165 MPa and elongation to failure of 35%.Comment: submitted to Met. Mater. Trans. A manuscript E-TP-12-953-
The redox transformations and nucleophilic replacements as possible metabolic reactions of the drug “Triazaverin”. The chemical modeling of the metabolic processes
As a model of metabolic transformations of antiviral drug “Triazaverin” and its analogues‑2-alkylthio‑6-nitro‑1,2,4-triazolo[5,1-c][1,2,4]triazine‑7-ones 1a-d examined the oxidation of alkylthio groups to the corresponding sulfoxides 2a-d and sulfones 3a-d, as well as the process of nucleophilic substitution sulfonyloxy group of cysteine and cysteamine with the formation of compounds 5 and 6
Exact diagonalization solver for the extended dynamical mean-field theory
We present an efficient exact diagonalization scheme for the extended
dynamical mean-field theory and apply it to the extended Hubbard model on the
square lattice with nonlocal charge-charge interactions. Our solver reproduces
the phase diagram of this approximation with good accuracy. Details on the
numerical treatment of the large Hilbert space of the auxiliary
Holstein-Anderson impurity problem are provided. Benchmarks with a numerically
exact strong-coupling continuous-time quantum-Monte Carlo solver show better
convergence behavior of the exact diagonalization in the deep insulator.
Special attention is given to possible effects due to the discretization of the
bosonic bath. We discuss the quality of real axis spectra and address the
question of screening in the Mott insulator within extended dynamical
mean-field theory.Comment: 12 pages, 8 figure
Mathematical Models of Video-Sequences of Digital Half-Tone Images
This chapter is devoted to Mathematical Models (MM) of Digital Half-Tone Images (DHTI) and their
video-sequences presented as causal multi-dimensional Markov Processes (MP) on discrete meshes.
The difficulties of MM development for DHTI video-sequences of Markov type are shown. These difficulties are related to the enormous volume of computational operations required for their realization.
The method of MM-DHTI construction and their statistically correlated video-sequences on the basis
of the causal multi-dimensional multi-value MM is described in detail. Realization of such operations
is not computationally intensive; Markov models from the second to fourth order demonstrate this. The
proposed method is especially effective when DHTI is represented by low-bit (4-8 bits) binary numbers
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