Dynamic recovery (DRV) and dynamic recrystallization (DRX) of hexagonal materials during hot deformation is a sub-domain of restoration processes, which has not well been addressed. In this work, the ...DRV and DRX mechanisms of high-temperature α phase in TiAl alloys were thoroughly investigated by microstructural characterization and crystallographic analysis with an extended intragranular misorientation axis (IGMA) analysis method. It was revealed that the nucleation of recrystallized grains experienced three steps: (ⅰ) the occurrence of stress-induced grain boundary bulging and the formation of symmetrical-tilt low-angle boundaries characterized by 〈0001〉 disorientation axis induced by prismatic slip; (ⅱ) the evolution of the low-angle boundaries into asymmetrical-tilt boundaries characterized by 〈101¯x〉 disorientation axis by local basal slip, or tilt-twist boundaries characterized by 〈112¯y〉 disorientation axis through rotational grain boundary sliding, resulting in the formation of subgrains from the boundary bulges; (ⅲ) the detachment of the subgrains and the mixing of the detached subgrains by grain boundary sliding. These three steps happened continuously and repeatedly from the boundary regions toward grain interior till the completion of recrystallization. This work provided original information of continuous DRX (CDRX) of hexagonal materials. The extended IGMA method developed in this study is helpful for related investigations.
•The mechanisms of dynamic recovery and recrystallization of the α phase in TiAl alloys has been thoroughly investigated.•Provide original information of continuous dynamic recrystallization of hexagonal materials.•The intragranular misorientation axis analysis method is extended for related investigations on deformation behavior.
We propose a new finite element method for embedded domain computations, which falls in the category of surrogate/approximate boundary algorithms. The key feature of the proposed approach is the idea ...of shifting the location where boundary conditions are applied from the true to the surrogate boundary, and to appropriately modify the shifted boundary conditions, enforced weakly, in order to preserve optimal convergence rates of the numerical solution. This process yields a method which, in our view, is simple, efficient, and also robust, since it is not affected by the small-cut-cell problem. Although general in nature, here we apply this new concept to the Poisson and Stokes problems. We present in particular the full analysis of stability and convergence for the case of the Poisson operator, and numerical tests for both the Poisson and Stokes equations, for geometries of progressively higher complexity.
In order to explore a new approach to construct surfaces bounded by geodesies or lines of curvature, a method of surface modeling based on fourth-order partial differential equations (PDEs) is ...presented. Compared with the free-form surface modeling based on finding control points, PDE-based surface modeling has the following three advantages. First, the corresponding biharmonic surface can naturally be derived under some degenerative conditions; second, the parameters in the PDE implicate some physical meaning, such as elasticity or rigidity; third, there are only a few parameters that need to be evaluated, and hence the computation is simple. In addition, this paper constructs two adjacent surfaces with C super(1) continuity whose common boundary is the same given curve as well as respective geodesic (or line of curvature). Examples show that this method to construct PDE-based surfaces bounded by geodesies or lines of curvature is easy and effective.
Purpose: To explore and characterize how the implementation and use of an electronic nursing module supports the care process, the interrelation of interdisciplinary documentation and the role of ...redundant information in the interplay between technology and clinical practice. Methods: A qualitative case study was carried out at a surgical ward and a post-anesthesia care unit (PACU). A mixed method of data collection was used, including semi-structured interviews, observation and document analysis. Results: The study revealed that the electronic care plan was used in daily practice, and international nursing classifications were extensively used. However, the study also illustrates a gap between nurse-specific documentation (care plans) and other sources of information used in the documentation of the care process, such as the medication sheet, medical chart, and a custom-designed medical chart used by the post-anesthesia care unit (PACU). Moreover, the study also highlights how redundant information can serve as a agluea in the socio-technical network to facilitate information sharing and coordination across domain-specific boundaries. Conclusions: Differentiating between negative and positive redundancy provides increased understanding of how the correlation of supplementary information has a role in the integration between work processes and computer systems. Coordination and pragmatic redundancies are emphasized to inform the further design and implementation of process-based electronic patient records (EPR).
CaCu sub(3)Ti sub(4)O sub(12) (CCTO) ceramics were synthesized by methods of sol-gel, traditional solid-state reaction, and thermal decomposition of organic solution. The results exhibit that the ...microstructures and electric characteristics are affected by the methods of synthesis. The X-ray diffraction patterns show that all samples have a perovskite-like CCTO phase. Moreover, CCTO ceramic from traditional solid-state reaction have the phases of TiO sub(2) and CuO. The scanning electron microscopy images show that CCTO ceramics from different methods have different grain sizes, grain boundaries, and densities. Dielectric properties of the CCTO ceramics were characterized in a broad frequency range (10-10 super(7) Hz) at room temperature. The CCTO ceramics from thermal decomposition of organic solution have the dielectric constant of more than 5 10 super(4) at 10 Hz. The nonlinear relationship between the current density and the electric field strength can be observed in all the three samples.
Keywords: chiral amplification; circularly polarized luminescence; phosphorescence; platinum(II) liquid crystals; symmetry breaking Obtaining homochirality from biased symmetry-breaking of ...self-assembly in achiral molecules remains a great challenge due to the lack of ingenious strategies and controlling their handedness. Here, we report the first case of biased symmetry breaking from achiral platinum (II) liquid crystals which self-organize into an enantiomerically enriched single domain without selection of handedness in twist grain boundary TGB .sup.*.sup. phase. Most importantly, the chiral control of self-organization can be achieved by using above the homochiral liquid crystal films with determined handedness (P or M) as a template. Moreover, benefiting from self-assembled superhelix, these complexes exhibit prominent circularly polarized luminescence with high |g.sub.lum| up to 3.4x10.sup.-3 in the TGB .sup.*.sup. mesophase. This work paves a neoteric avenue for the development of chiral self-assemblies from achiral molecules. Supporting information: Additional Supporting Information may be found in the online version of this article As a service to our authors and readers, this journal provides supporting information supplied by the authors. Such materials are peer reviewed and may be re-organized for online delivery, but are not copy-edited or typeset. Technical support issues arising from supporting information (other than missing files) should be addressed to the authors. CAPTION(S): Supplementary Byline: Bo Yang, Guo Zou, Shilin Zhang, Hailiang Ni, Haifeng Wang, Wei Xu, Cheng Yang, Hui Zhang, Wenhao Yu, Kaijun Luo
The eastern edge of Europe has always been in flux. As a result, the nature of the Ukrainian-Russian relationship is both complex and ambiguous. Prompted by the countries' historical and geographical ...entanglement, Volodymyr V. Kravchenko asks what the words "Ukraine" and "Russia" really mean.
Partitioning of chromosomes into euchromatic and heterochromatic domains requires mechanisms that specify boundaries. The S. pombe JmjC family protein Epe1 prevents the ectopic spread of ...heterochromatin and is itself concentrated at boundaries. Paradoxically, Epe1 is recruited to heterochromatin by HP1 silencing factors that are distributed throughout heterochromatin. We demonstrate here that the selective enrichment of Epe1 at boundaries requires its regulation by the conserved Cul4-Ddb1 super(Cdt2) ubiquitin ligase, which directly recognizes Epe1 and promotes its polyubiquitylation and degradation. Strikingly, in cells lacking the ligase, Epe1 persists in the body of heterochromatin thereby inducing a defect in gene silencing. Epe1 is the sole target of the Cul4-Ddb1 super(Cdt2) complex whose destruction is necessary for the preservation of heterochromatin. This mechanism acts parallel with phosphorylation of HP1/Swi6 by CK2 to restrict Epe1. We conclude that the ubiquitin-dependent sculpting of the chromosomal distribution of an antisilencing factor is critical for heterochromatin boundaries to form correctly.
The Political Materialities of Borders seeks to produce social theory at/from the border; rather than apprehending the border as mere epiphenomenon to urban or state-driven social theoretical ...dynamics, it calls for a specificity to the border in border studies as a rejuvenated space for theoretical enquiry.
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