Fabrication of continuous slim aluminum fibers using a multi-tooth tool

In this paper, we describe the development of a multi-tooth tool to fabricate continuous, slim aluminum fibers of an equivalent diameter of under 100?µm. Following an analysis of the process of the fabrication of aluminum fibers, we designed a geometric cutting model of the multi-tooth tool with a large inclination as well as the mechanism to form continuous, slim aluminum fibers. We conducted experiments to determine the influence of process parameters on the surface topography and the equivalent diameter of the aluminum fiber. We obtained the continuous, slim aluminum fibers with a micro-fin structure when the cutting speed, cutting depth, and feed rate were in the ranges of 0.08–0.18?mm, 5–15?m/min, and 0.1–0.2?mm/r, respectively. We found that the equivalent diameter of the aluminum fiber gradually increased with decreasing cutting speed, and increasing feed rate and cutting depth. Moreover, the result of a composition analysis indicated that the generated cutting heat had a minimal effect on the oxidation of the aluminum fiber.     

Toward a molecular design of porous carbon materials

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Catheter‐related fungal endocarditis caused by Candida parapsilosis in a hemodialysis patient

Fungal endocarditis (FE) is commonly regarded as a rare but fatal disease. The incidence of infective endocarditis (IE) in hemodialysis (HD) patients is thought to be obviously higher than that in the general population. Moreover, IE occurs more likely in HD patients with catheters. With the increase of HD population and extensive use of catheters in HD patients, FE, as a special form of IE, may increase and bring new challenges to clinicians. We reported a case of FE associated with catheter infection in a 44‐year‐old woman on HD. The risk factors and treatment strategies of FE in HD patients were discussed.     

The Effect of the Rotary Steerable Spindle Structure Parameters on the Characteristics of Cantilever Bearing

Journal of Failure Analysis and Prevention - In point-the-bit rotary steerable drilling system, the internal and outer diameter of the spindles and the fillet radius of the shaft shoulder have a...     

Spinel-layered integrate structured nanorods with both high capacity and superior high-rate capability as cathode material for lithium-ion batteries

Spinel phase LiMn2O4 was successfully embedded into monoclinic phase layeredstructured Li2MrnO3 nanorods,and these spinel-layered integrate structured nanorods showed both high capacities and superior high-rate capabilities as cathode material for lithium-ion batteries (LIBs).Pristine Li2MnO3 nanorods were synthesized by a simple rheological phase method using α-MnO2 nanowires as precursors.The spinel-layered integrate structured nanorods were fabricated by a facile partial reduction reaction using stearic acid as the reductant.Both structural characterizations and electrochemical properties of the integrate structured nanorods verified that LiMn2O4 nanodomains were embedded inside the pristine Li2MnO3 nanorods.When used as cathode materials for LIBs,the spinel-layered integrate structured Li2MnO3 nanorods (SL-Li2MnO3) showed much better performances than the pristine layered-structured Li2MnO3 nanorods (L-Li2MnO3).When charge-discharged at 20 mA·g-1 in a voltage window of 2.0-4.8 V,the SL-Li2MnO3 showed discharge capadties of 272.3 and 228.4 mAh.g-1 in the first and the 60th cycles,respectively,with capacity retention of 83.8％.The SL-Li2MnO3 also showed superior high-rate performances.When cycled at rates of 1 C,2 C,5 C,and 10 C (1 C =200 mA·g-1) for hundreds of cycles,the discharge capacities of the SL-Li2MnO3 reached 218.9,200.5,147.1,and 123.9 mAh·g-1,respectively.The superior performances of the SL-Li2MnO3 are ascribed to the spineMayered integrated structures.With large capacities and superior high-rate performances,these spinel-layered integrate structured materials are good candidates for cathodes of next-generation high-power LIBs.     

Identification of Pivotal Causes and Spreaders in the Time‐Varying Fault Propagation Model to Improve the Decision Making under Abnormal Situation

Under abnormal conditions, timely and effective decisions of system recovery and protective measures are of great significance for safety‐critical systems. The knowledge of the roles that network nodes play in the spreading process is crucial for developing efficient maintenance decisions; for singling out and preferential control, the ‘pivotal spreaders’ may be a way to maximize the chances to timely hinder the fault pervasion. Inspired by the inhomogeneous topological nature of a complex fault propagation network, this study is devoted to exploring the spreading capabilities of nodes regarding both structural connectivity and causal influence strength, so as to provide decisions of preferential recovery actions under specific fault scenarios. Specifically, the dynamic betweenness centrality and nonsymmetrical entropy are incorporated to adaptively measure the system‐wide fault diffusion risk of a set of controllable fault events. In order to model the dynamics and uncertainties involved in the complex fault spreading process, we introduce the model of a dynamic uncertain causality graph, based on which solutions of time‐varying structure decomposition and causality reduction are adopted to improve the reasoning efficiency. Verification experiments consisting of simulated calculation cases and generator faults of a nuclear power plant show empirically the effectiveness and applicability of this method in large‐scale engineering practice. Copyright © 2014 John Wiley & Sons, Ltd.