Heat Resistance of Electric Arc Coatings Made of Fe–Cr–B–Al Powder Wire

Electric metallized coatings made of Fe–Cr–B–Al powder wire possess a high heat resistance at 700–800°C at the level of compact 08Kh13 material. During 5–7 h, the coating is subjected to intense internal oxidation, which prevents oxygen penetration into the base material. To obtain heat-resistant electric metallized coatings of powder wire, it is necessary to form a structure with controlled heterogeneity by adding a certain quantity of Al and Mg to the charge.     

Effect of Si addition on the microstructure of an Fe-8.0AI-29.0Mn-0.90C alloy

The microstructures of two alloys with Fe-8.0Al-29.0Mn-0.90C, one without Si and one with 1.5 wt pct Si, have been investigated by means of transmission electron microscopy (TEM). In the as-quenched condition, the alloy without Si is single-phase austenite; however, some discrete particles along the austenite grain boundaries can be observed in the Si-bearing alloy. The discrete particles have a mixture of (α + D0₃) phases, indicating that the Si addition enhances the formation of (α + D0₃) phases. This result is in disagreement with those reported by other research on Fe-Al-Mn-Si-C alloys. Transmission electron microscopy examinations reveal that the (α + D0₃) phases are formed by an ordering transition during quenching. When the quenched specimen is aged at temperatures ranging from 450 °C to 1050 °C, the phase transformation sequence occurring within the (α + D0₃) region as the temperature increases is found to be D0₃→ (D0₃ +K phase) → B2 → α.     

Influence of the Porosity of a Plasma-Electrolytic Coating on the Corrosion Resistance of D16 Alloy

Materials Science - We study the effect of the coating thickness on the corrosion resistance and porosity of oxide-ceramic coatings on D16 alloy. The coatings were synthesized in an alkaline...     

Harnessing the Power of GPUs to Speed Up Feature Selection for Outlier Detection

Acquiring a set of features that emphasize the differences between normal data points and outliers can drastically facilitate the task of identifying outliers. In our work, we present a novel non-parametric evaluation criterion for filter-based feature selection which has an eye towards the final goal of outlier detection. The proposed method seeks the subset of features that represent the inherent characteristics of the normal dataset while forcing outliers to stand out, making them more easily distinguished by outlier detection algorithms. Experimental results on real datasets show the advantage of our feature selection algorithm compared with popular and state-of-the-art methods. We also show that the proposed algorithm is able to overcome the small sample space problem and perform well on highly imbalanced datasets. Furthermore, due to the highly parallelizable nature of the feature selection, we implement the algorithm on a graphics processing unit （GPU） to gain significant speedup over the serial version. The benefits of the GPU implementation are two-fold, as its performance scales very well in terms of the number of features, as well as the number of data points.     

Channel Aware Opportunistic Routing in Multi-Radio Multi-Channel Wireless Mesh Networks

Opportunistic routing （OR） involves multiple candidate forwarders to relay packets by taking advantage of the broadcast nature and multi-user diversity of the wireless medium. Compared with traditional routing （TR）, OR is more suitable for the unreliable wireless link, and can evidently improve the end to end throughput. At present, there are many achievements concerning OR in the single radio wireless network. However, the study of OR in multi-radio wireless network stays the beginning stage. To demonstrate the benefit of OR in multi-radio multi-channel network, we propose a new route metric -- multi-channel expected anypath transmission time （MEATT）, which exploits the channel diversity and resource of multiple candidate forwarders for OR. Based on the new metric, a distributed Mgorithm named Channel Aware Opportunistic Routing （CAOR） is proposed. The simulation results demonstrate that MEATT improves 1.14 and 1.53 times of the average throughput than existing expected anypath transmission time （EATT）and metric of interference and channel switching cost （MIC） respectively. The average delay of MEATT is 17% and 40% lower than those of EATT, MIC, respectively.     

Improvement of the Functional Characteristics of Coatings Obtained By the Method of Hard Anodizing of Aluminum Alloys

Materials Science - We analyzed the ways of improvement of the functional properties of coatings on aluminum alloys obtained by the method of hard anodizing. It is shown that the protective...     

英国电信重组计划探究

英国电信公司近期宣布了其重组计划，它将重组为４个新的部门：Ｉｇｎｉｔｅ、ＢＴｏｐｅｎｗｏｒｌｄ、ＢＴ Ｗｉｒｅｌｅｓｓ和Ｙｅｌｌ。英国曜的重组归因于多方面因素的综合作用，包括技术进步、市场结构、用户需求以及管理职能和融资能力。此次重组打破了地域的界限，按业务重新划分，是一次彻底的结构调整。本文对英国电信的重组计划进行了详尽的分析。     

Effects of macroscopic defects on the damping behavior of aluminum and Zn-27 Pct Al alloy

A study was carried out on the influence of macroscopic defects on the damping behavior of commercially pure Al and Zn-27 pct Al alloy. The macroscopic defects, pores, and graphite particulates with a size of 0.001±0.0005 m and volume fractions ranging from 19 to 94 pct were introduced into the structures by infiltration technology. It has been shown that pores or graphite particulates can improve the damping capacity of commercially pure Al, due to the interaction between macro- and microdefects. Pores, however, show no detectable effects on the damping behavior of high damping Zn-27 pct Al alloy. Similarly, graphite particulates have little effect on the damping capacity of Zn-27 pct Al alloy at low temperatures and, on the contrary, make the transformation peak value of internal friction decrease. It is considered that graphite particulate may repress the eutectoid transformation process of Zn-27 pct Al alloy.     

N‐Stearoylethanolamine Restores Pancreas Lipid Composition in Obesity‐Induced Insulin Resistant Rats

This study investigates the protective effect of N‐stearoylethanolamine (NSE), a bioactive N‐acylethanolamine , on the lipid profile distribution in the pancreas of obesity‐induced insulin resistant (IR) rats fed with prolonged high fat diet (58 % of fat for 6 months). The phospholipid composition was determined using 2D thin‐layer chromatography. The level of individual phospholipids was estimated by measuring inorganic phosphorus content. The fatty acid (FA) composition and cholesterol level were investigated by gas–liquid chromatography. Compared to controls, plasma levels of triglycerides and insulin were significantly increased in IR rats. The pancreas lipid composition indicated a significant reduction of the free cholesterol level and some phospholipids such as phosphatidylcholine (PtdCho), phosphatidylethanolamine (PtdEtn), phosphatidylinositol (PtdIns), phosphatidylserine (PtdSer) compared to controls. Moreover, the FA composition of pancreas showed a significant redistribution of the main FA (18:1n‐9, 18:2n‐6, 18:3n‐6 and 20:4n‐6) levels between phospholipid, free FA, triglyceride fractions under IR conditions that was accompanied by a change in the estimated activities of Δ9‐, Δ6‐, Δ5‐desaturase. Administration of N‐stearoylethanolamine (NSE, 50 mg/kg daily per os for 2 weeks) IR rats triggered an increase in the content of free cholesterol, PtdCho and normalization of PtdEtn, PtdSer level. Furthermore, the NSE modulated the activity of desaturases, thus influenced FA composition and restored the FA ratios in the lipid fractions. These NSE‐induced changes were associated with a normalization of plasma triglyceride content, considerable decrease of insulin and index HOMA‐IR level in rats under IR conditions.