Simultaneous Improvement in the Strength and Formability of Commercially Pure Titanium via Twinning-induced Crystallographic Texture Control

The rolling texture formed in the conventional cold rolling process of commercially pure titanium (CP-Ti) for producing a metal sheet significantly limits the potential applications of CP-Ti sheets in various industrial sectors by impairing the formability. Here, we report that by exploiting a twinning-induced crystallographic texture modification, the rolling texture can be weakened and dispersed effectively, leading to a simultaneous improvement in the formability and yield strength. A two-stage cold rolling process was designed with intermediate annealing at a late stage of the conventional cold rolling process to generate deformation twins. The intermediate annealing drove the activation of {11 (2) over bar2} twin and {11 (2) over bar2}-{10 (1) over bar2} double twin in the second stage of the rolling process by removing the internal reaction stress developed in the first stage of the rolling process through recrystallization, and the crystallographic feature of the {1122} twinned region, i.e., {11 (2) over bar2} twin texture, was effective for type slips and {10 (1) over bar2} twinning to accommodate a through-thickness strain as well as for reducing the planar anisotropy. This enhanced thinning capability and reduced planar anisotropy in the {11 (2) over bar2} twin texture led to an improvement of the formability. We demonstrated the feasibility of the suggested two-stage cold rolling process with ASTM grade 2 CP-Ti.11Ysciescopu

Ho Chi Minh Ville : de la migration à l'emploi

L'agglomération de Ho Chi Minh Ville est le principal pôle de développement du Viêtnam. La politique de libéralisation économique mise en oeuvre depuis 1986 est en train de bouleverser l'économie de la ville, ce qui entraîne notamment une forte croissance économique, un accroissement des disparités ville-campagne, une augmentation des flux migratoires, un développement du secteur privé, un élargissement des disparités sociales en ville. Parallèlement, le contrôle de l'immigration en ville, depuis longtemps strict, avec l'instauration d'un permis de résidence, est devenu beaucoup plus lâche. Dans ce contexte, les principales caractéristiques de la migration et de l'emploi en ville sont analysées à partir des résultats d'une enquête menée en 1994. Certaines données sont semblables à ce que l'on rencontre dans d'autres pays de l'Asie du Sud-Est, telle que la prépondérance des femmes parmi les migrants. D'autres résultats sont plus originaux, comme l'éducation assez élevée du migrant, le maintien du chômage à un niveau inférieur à ce qu'on aurait pu craindre, l'insertion limitée du migrant dans le secteur informel, le revenu relativement élevé du migrant... Cependant, l'évolution en cours laisse présager une modification très rapide de la situation avec une très forte croissance urbaine à venir, même si les données démographiques récentes manquent cruellement, le dernier recensement datant de 1989. Cette urbanisation sera très difficile à maîtriser et ses conséquences risquent d'être négatives à terme. Une des solutions serait le développement des centres urbains secondaires destinés à faire "tampon" sur les axes de migration de la campagne vers la grande ville. (Résumé d'auteur

A comparison of the growth potential of Dover sole (Solea solea) and Senegal sole (Solea senegalensis) under intensive rearing conditions

This trial was set up to compare the growth performance of Dover sole and Senegal sole under intensive rearing conditions

Systematic Digitized Treatment of Engineering Line-Diagrams

YesIn engineering design, there are many functional relationships which are difficult to express into a simple and exact mathematical formula. Instead they are documented within a form of line graphs (or plot charts or curve diagrams) in engineering handbooks or text books. Because the information in such a form cannot be used directly in the modern computer aided design (CAD) process, it is necessary to find a way to numerically represent the information. In this paper, a data processing system for numerical representation of line graphs in mechanical design is developed, which incorporates the process cycle from the initial data acquisition to the final output of required information. As well as containing the capability for curve fitting through Cubic spline and Neural network techniques, the system also adapts a novel methodology for use in this application: Grey Models. Grey theory have been used in various applications, normally involved with time-series data, and have the characteristic of being able to handle sparse data sets and data forecasting. Two case studies were then utilized to investigate the feasibility of Grey models for curve fitting. Furthermore, comparisons with the other two established techniques show that the accuracy was better than the Cubic spline function method, but slightly less accurate than the Neural network method. These results are highly encouraging and future work to fully investigate the capability of Grey theory, as well as exploiting its sparse data handling capabilities is recommended

Gonad Development of male Sole, S. solea (L.), in natural and culture conditions between March and June 2003 in relation to environmental factors

The aim of the present study was to detect differences of spermatogenesis between wild, captured and reared (F1) sole (Solea solea L.) broodstock. Differences between sampling months March and June 2003 as well as differences between groups were determined

Break-junction tunneling measurements of the high-\u3ci\u3eT\u3c/i\u3e\u3csub\u3e\u3ci\u3ec\u3c/i\u3e\u3c/sub\u3e superconductor Y\u3csub\u3e1\u3c/sub\u3eBa\u3csub\u3e2\u3c/sub\u3eCu\u3csub\u3e3\u3c/sub\u3eO\u3csub\u3e9- δ \u3c/sub\u3e

Current-voltage tunneling characteristics in a high-critical-temperature superconducting material containing predominately Y1Ba2Cu3O9- δ have been measured using the break-junction technique. Sharp gap structure was observed, with the largest superconductive energy gap measured to be Δ=19.5±1 meV, assuming a superconductor-insulator-superconductor junction. This energy gap corresponds to 2Δ/kBTc=4.8 at T=4 K, for a critical temperature of 93 K (midpoint of the resistive transition)

Parity-violating asymmetry in γd→n⃗p\gamma d \to \vec{n}p with a pionless effective theory

Nuclear parity violation is studied with polarized neutrons in the photodisintegration of the deuteron at low energies. A pionless effective field theory with di-baryon fields is used for the investigation. Hadronic weak interactions are treated by parity-violating di-baryon-nucleon-nucleon vertices, which have undetermined coupling contants. A parity-violating asymmetry in the process is calculated for the incident photon energy up to 30 MeV. If experimental data for the parity-violating asymmetry become available in the future, we will be able to determine the unknown coupling contants in the parity-violating vertices.Comment: 4 pages. A contribution to APFB2011, August 22-26, 2011, Seoul, Kore

Infrared emission bands and thermal effects for 440-nm-emitting GaN-based laser diodes

Broad emission bands due to defects in (In,Ga,Al)N laser diodes operating at 440 nm are investigated using continuous-wave and pulsed currents. In addition to known yellow-green and short-wave infrared bands, defect emissions were observed even in the medium-wave infrared range. A separation from thermal radiation is possible. When using pulsed currents, a super-linearly increasing emission occurs at ∼1150 nm, which could be attributed to amplified spontaneous emission mainly due to the electroluminescence of deep defects in the optically active region. These results may be useful in interpreting the output power bottleneck of GaN-based lasers compared to mature GaAs-based lasers. © 2020 Author(s). All article content, except where otherwise noted, is licensed under a Creative Commons Attribution (CC BY) license (http://creativecommons.org/licenses/by/4.0/). https://doi.org/10.1063/1.514380

Synchronization in a System of Globally Coupled Oscillators with Time Delay

We study the synchronization phenomena in a system of globally coupled oscillators with time delay in the coupling. The self-consistency equations for the order parameter are derived, which depend explicitly on the amount of delay. Analysis of these equations reveals that the system in general exhibits discontinuous transitions in addition to the usual continuous transition, between the incoherent state and a multitude of coherent states with different synchronization frequencies. In particular, the phase diagram is obtained on the plane of the coupling strength and the delay time, and ubiquity of multistability as well as suppression of the synchronization frequency is manifested. Numerical simulations are also performed to give consistent results