Predictive maintenance of abnormal wind turbine events by using machine learning based on condition monitoring for anomaly detection

Journal of Mechanical Science and Technology - The predictive maintenance of wind turbines has become a critical issue with the rapid development of wind power generation. The early detection of...     

Preparation and characterization of lactitol-based poly(ether polyol)s for rigid polyurethane foam

Propoxylation of lactitol [4-O-β-D -galactopyranosyl-D -glucitol] under alkaline conditions afforded poly(ether polyol)s (PEP) which have been characterized by their unsaturation content, alpha color, hydroxyl number, viscosity, hygroscopicity, and molecular weight distribution. The analogous sucrose-based PEP were prepared for comparison. Lactitol was found to require shorter reaction times and produced lighter-colored polyols than did sucrose. Polyols produced from lactitol displayed similar physical properties to sucrose-based PEP. Molecular weight analysis by GPC using the universal calibration method showed lactitol PEP to have polydispersities between 1.04 and 1.07. Negligible decomposition of lactitol during propoxylation was confirmed by ¹³C-NMR and GPC. ¹H-NMR of trifluoroacetyl derivatives of lactitol PEP afforded secondary determination of M_n. In addition, rigid polyurethane foams (PURF) formulated with lactitol-, sucrose-, or commercial sucrose–glycerin-based polyols and PAPI 27 were prepared and characterized. Lactitol-based PURF were found to compare favorably with sucrose-based foams, displaying a density and compressive strength of 28.9 kg/m³ and 1.213 × 10⁵ N/M², respectively. © 1996 John Wiley & Sons, Inc.     

Green and Highly-Efficient Microwave Synthesis Route for Sulfur/Carbon Composite for Li-S Battery

Multiporous carbons (MPCs) are prepared using ZnO as a hard template and biomass pyrolysis oil as the carbon source. It is shown that the surface area, pore volume, and mesopore/micropore ratio of the as-prepared MPCs can be easily controlled by adjusting the ZnO/oil ratio. Sulfur/MPC (S/MPC) composite is prepared by blending sulfur powder with the as-prepared MPCs followed by microwave heating at three different powers (100 W/200 W/300 W) for 60 s. The unique micro/mesostructure characteristics of the resulting porous carbons not only endow the S/MPC composite with sufficient available space for sulfur storage, but also provide favorable and efficient channels for Li-ions/electrons transportation. When applied as the electrode material in a lithium-ion battery (LIB), the S/MPC composite shows a reversible capacity (about 500 mAh g⁻¹) and a high columbic efficiency (>95%) after 70 cycles. Overall, the method proposed in this study provides a simple and green approach for the rapid production of MPCs and S/MPC composite for high-performance LIBs.     

Self-assisted wound healing using piezoelectric and triboelectric nanogenerators

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Polymeric g-C3N4 Derived from the Mixture of Dicyandiamide and Mushroom Waste for Photocatalytic Degradation of Methyl Blue

Topics in Catalysis - Metal-free, visible light-responsive, carbon-based graphitic carbon nitride (g-C3N4) is a well-known photocatalyst. It is necessary to develop a g-C3N4 for use as a...     

Investigation of hygienic quality and freshness of marketed fresh seafood in Northern Taiwan

To survey the hygienic quality and freshness of fresh fish and shellfish, 533 specimens of fish and shellfish were collected from fishing piers, traditional markets and supermarkets (including warehouses) in northern Taiwan during the winter (January-February) and summer (July-August) seasons for hygienic quality and freshness examinations. The indicators included total bacterial count, fecal coliform, Escherichia coli, volatile basic nitrogen (VBN) and K value judged from ATP-related compounds. It was found that the hygienic quality and freshness of fish and shellfish decreased in summer, especially for clam and mussel. The ratio of unacceptable hygienic quality or freshness of fish and shellfish was the highest in fecal coliform, followed by E. coli and others. The fecal coliform count in products from the traditional markets was the highest, followed by those from supermarkets and fishing piers. Secondary contamination seems to be the most important problem for hygienic quality and freshness of fish and shellfish.     

Regulation of Ferroptosis by Non-Coding RNAs in Head and Neck Cancers

Ferroptosis is a newly identified mode of programmed cell death characterized by iron-associated accumulation of lipid peroxides. Emerging research on ferroptosis has suggested its implication in tumorigenesis and stemness of cancer. On the other hand, non-coding RNAs have been shown to play a pivotal role in the modulation of various genes that affect the progression of cancer cells and ferroptosis. In this review, we summarize recent advances in the theoretical modeling of ferroptosis and its relationship between non-coding RNAs and head and neck cancers. Aside from the significance of ferroptosis-related non-coding RNAs in prognostic relevance, we also review how these non-coding RNAs participate in the regulation of iron, lipid metabolism, and reactive oxygen species accumulation. We aim to provide a thorough grounding in the function of ferroptosis-related non-coding RNAs based on current knowledge in an effort to develop effective therapeutic strategies for head and neck cancers.     

Error-tolerability enhancement via bit inversion and median filtering for single-bit errors in image processing circuits

Microsystem Technologies - Error-tolerance has been proposed as a new method to increase effective yield of a system. The basic idea is that faulty chips might be still acceptable as long as their...     

Lattice relations and solidification of the complex regular eutectic (Cr,Fe)-(Cr,Fe)<Subscript>23</Subscript>C<Subscript>6</Subscript>

The eutectic (Cr,Fe)-(Cr,Fe)₂₃C₆ showed a triaxial fishbone structure and could be categorized as a “complex regular structure”. In this study, the lattice relations of the fishbone (Cr,Fe)₂₃C₆ were examined and the solidification process was observed using a transmission electron microscope and a confocal laser scanning microscope. For one of the three fish bones in a eutectic cell, parallel (Cr,Fe)₂₃C₆ lamellas at one side of the spine had the same lattice direction, as did those in the (Cr,Fe) phase. The lattices of neighboring (Cr,Fe)₂₃C₆ and (Cr,Fe) phases were not coherent. Lamellar (Cr,Fe)₂₃C₆ on opposite sides of a spine had different lattice directions, and their lattice boundary was in the spine. By using the confocal laser scanning microscope, the solidification of lamellar eutectic structure could be observed. At the low cooling rate of 5 o C·min^-1, parallel lamellas would grow thick blocks instead of thin plates. To obtain a thin lamellar eutectic structure, the cooling rate should be higher, like the rate in welding.