A semiautomated electron backscatter diffraction technique for extracting reliable twin statistics

A framework has been developed for extracting reliable twin statistics from a deformed microstructure using crystallographic twin identification techniques with spatially correlated electron backscatter diffraction (EBSD) data. The key features of this analysis are the use of the mathematical definition of twin relationships, the inclination of the common K ₁ plane at a twin boundary, and the correct identification of the parent orientation in a parent/twin pair. Methods for identifying the parent in a parent/twin pair will be briefly discussed and compared. Twin area fractions are then categorized by operative twin systems, number of active twin variants in each system, and corrected twin widths. These statistics are reported here for α-zirconium samples deformed in quasi-static four-point bend beams and in a 100 m/s Taylor cylinder impact test. Analysis of the statistics also begins to reveal the roles that deformation rate and relative orientation of the boundary conditions to the material’s symmetry axes play in determining the twinning activity that accommodates the imposed boundary conditions. These improved twin statistics can help quantify the deformation processes in materials that deform by twinning as well as serve to provide better validation of proposed models of the deformation processes.     

量化网络风险

基本风险分析技术能帮助您从整个电力行业分布的角度了解工业控制系统和SCADA(数据采集与监控)系统中的网络威胁。这一步骤将帮助您规划一个防御性的策略。2006年8月19号,Brown' s Ferry核电站因为过程控制网络流量过大而堵塞,导致了再循环泵的损坏。操作员按照操作手册要求将其关闭,并将系统调整到安全状态。一份后续的美国核管理委员会(NRC)报告确定其根源为未确定来源的车间计算机网络通信量过大。由此采取了运     

On the reconstruction of polycrystalline microstructures from two-point correlation statistics

An exhaustive branching technique is introduced for reconstructing discrete microstructures from two-point statistic occurrences. It is shown that two-point statistics control microstructure, to the extent that exact replicas of discrete microstructures are produced when sufficient two-point statistic occurrences are matched. Efficiency comparisons between simulated-annealing methods and the exhaustive branching method are made on polycrystalline structures and some discussion on advancing the exhaustive branching method is given.     

Influence of shock prestraining on the formation of shear localization in 304 stainless steel

Adiabatic shear localization was studied in both annealed (as-received) and shock-prestrained 304 stainless steels (304 SS). A forced shear technique was used to probe the evolution of shear localization under high-strain-rate loading using a compression split-Hopkinson pressure bar (SHPB) and hatshaped specimens. The shearing responses of the shock-prestrained steel at high strain rate indicate that they exhibit a higher initial yield strength but a lower work-hardening rates than those observed in the annealed steel. The shock-prestrained specimens, having achieved an unstable condition at a smaller plastic displacement and a lower flow stress, were seen to exhibit distinct sharp-edged bands. Corresponding comparisons between the mechanical responses and the deformed microstructures demonstrate that loading-path dependency exerts a strong influence on shear-band formation. The shock-prestrained 304 SS displayed a higher incidence of deformation twins, slip bands, and dislocation debris prior to the shear tests, this substructure suppressed further dislocation storage (work hardening) and thereby facilitated the propensity for shear localization.     

Screening of selected Asian spices for anti obesity-related bioactivities

The potential health effects of 30 spices, commonly used for daily consumption, were submitted to bioactivity screening with several anti-obesity related bioassays: adenosine A1 receptor binding, cannabinoid CB1 receptor binding, TNF-α and 3T3-L1 adipocytes differentiation induction. Sesame seed and red chilli exhibited high binding activity to the adenosine A1 receptor and nutmeg, mace, black pepper and turmeric to the cannabinoid CB1 receptor, while piment and turmeric showed high inhibition of TNF-α accumulation. Black onion seed proved to be the only spice with high 3T3-L1 adipocyte differentiation induction activity. Several well known major compounds found in these active spices were tested with the respective bioassays but did not show activity. Thus, it appears that other minor compounds or the synergistic effects of different constituents are responsible for the observed activity.     

Plant-Derived Food Ingredients for Stimulation of Energy Expenditure

The development of obesity is related to the regulation of energy intake, energy expenditure, and energy storage in the body. Increasing energy expenditure by inducing lipolysis followed by fat oxidation is one of the alternatives which could help to reverse this increasingly widespread condition. Currently, there is no approved drug targeting on stimulation of energy expenditure available. The use of herbal medicines has become a preferred alternative, supported by the classical consensus on the innocuity of herbal medicine vs synthetic drugs, something that often lacks a scientific basis (ban on Ephedra, for example). The inclusion of functional food in the daily diet has also been promoted although its efficacy requires further investigation. This review summarizes the results of recent work focused on the investigation of edible plant materials targeted at various important pathways related to stimulation of energy expenditure. The aim is to evaluate a number of plants that may be of interest for further studies because of their potential to provide novel lead compounds or functional foods which may be used to combat obesity, but require further studies to evaluate their antiobesity activity in humans.     

In-House Networks Using Multimode Polymer Optical Fiber for Broadband Wireless Services

A novel system concept is presented to transport microwave signals over an in-house multimode graded-index polymer optical fiber network, in order to feed the radio access points in high-capacity wireless LANs. By employing optical frequency multiplying, the network's intrinsically limited bandwidth is overcome. The feasibility of this concept to carry data at several hundreds of Mbit/s speed for various microwave signal formats at carrier frequencies in the tens of GHz range is shown. The concept enables cost-effective system implementation, and easy upgrading by offering data signal transparency. It can readily be integrated with other system technologies such as wired Gigabit Ethernet in a single multi-service in-house polymer optical fiber network.