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To realize the classification of lubricating oil types using mid-infrared (MIR) spectroscopy, linear discriminant analysis (LDA) was used for the dimensionality reduction of spectrum data, and the classification model was established based on the support vector machine (SVM). The spectra of the samples were pre-processed by interval selection, Savitzky–Golay smoothing, multiple scattering correction, and normalization. The Kennard–Stone algorithm (K/S) was used to construct the calibration and validation sets. The percentage of correct classification (%CC) was used to evaluate the model. This study compared the results obtained with several chemometric methods: PLS-DA, LDA, principal component analysis (PCA)-SVM, and LDA-SVM in MIR spectroscopy applications. In both calibration and verification sets, the LDA-SVM model achieved 100% favorable results. The PLS-DA analysis performed poorly. The cyclic resistance ratio (CRR) of the calibration set was classified via the LDA and PCA-SVM analysis as 100%, but the CRR of the verification set was not as good. The LDA-SVM model was superior to the other three models; it exhibited good robustness and strong generalization ability, providing a new method for the classification of lubricating oil types by MIR spectroscopy. [ABSTRACT FROM AUTHOR]

MnO2 nanowires/polyaniline composite (MnO2NW/PANI) was prepared by combining one-dimensional MnO2 nanowires (MnO2NW) with conductive polymer PANI surface coating. The MnO2NW were synthesized via a one-pot facile hydrothermal method. The composite MnO2NW/PANI was then prepared by in situ polymerization of aniline monomer on the surface of MnO2NW. The MnO2NW/PANI was able to serve as electroactive material and demonstrated a specific capacitance of 306.7 F/g recorded at a current density is 0.5 A/g, which is 28.4% higher than that of pristine MnO2 (only 238.9 F/g). The reduced electric resistance within MnO2NW/PANI interconnection networks and the good synergistic effect between MnO2NW and PANI for fast ion/charge transfer supports the enhanced capacitance of the composite. In addition, the MnO2NW/PANI composite electrode shows stable cycle performance, with capacity retention of 88.7% after 5000 repeated cycles test at a high current density of 5 A/g. The constructed nanocomposites have great potential in the further development of high-performance electrochemical electrode materials for energy storage application. [ABSTRACT FROM AUTHOR]

Cultivation of green manure (GM) crops in intensive cropping systems is important for enhancing crop productivity through soil quality improvement. We investigated yield sustainability, nutrient stocks, nutrient balances and enzyme activities affected by different long- term (1982−2016) green manure rotations in acidic paddy soil in a double-rice cropping system. We selected four treatments from a long-term experiment, including (1) rice-rice-winter fallow as a control treatment (R-R-F), (2) rice-rice-milkvetch (R-R-M), (3) rice-rice-rapeseed (R-R-R), and (4) rice-rice-ryegrass (R-R-G). The results showed that different GM rotations increased grain yield and the sustainable yield index compared with those of the R-R-F treatment. Compared with those of R-R-F, the average grain yield of early rice in R-R-M, R-R-R, and R-R-G increased by 45%, 29%, and 27%, respectively and that of late rice increased by 46%, 28%, and 26%, respectively. Over the years, grain yield increased in all treatments except R-R-F. Green manure also improved the soil chemical properties (SOM and total and available N and P), except soil pH, compared to those of the control treatment. During the 1983−1990 cultivation period, the soil pH of the R-R-M treatment was lower than that of the R-R-F treatment. The addition of green manure did not mitigate the soil acidification caused by the use of inorganic fertilizers. The soil organic matter (SOM), total nitrogen (TN) and total phosphorus (TP) contents and stocks of C, N and P increased over the years. Furthermore, GM significantly increased phosphatase and urease activities and decreased the apparent N and P balances compared with those in the winter fallow treatment. Variance partitioning analysis revealed that soil properties, cropping systems, and climatic factors significantly influenced annual grain yield. Aggregated boosted tree (ABT) analysis quantified the relative influences of the different soil properties on annual grain yield and showed that the relative influences of TN content, SOM, pH, and TP content on annual crop yield were 27.8%, 25.7%, 22.9%, and 20.7%, respectively. In conclusion, GM rotation is beneficial for sustaining high crop yields by improving soil biochemical properties and reducing N and P balances in acidic soil under double- rice cropping systems.

Strategy framing is usually studied in the context of news coverage about domestic Western politics. This study expands its application to news reports on the China-US trade war—an inter-state conflict including a democratic and one-party dominant system—thereby adding an international dimension to the study of strategy framing. Through a manual content analysis of news coverage from China, the US, Singapore, and Ireland (from January 2013 to January 2020; n = 1872), we investigate whether media independence, conflict involvement, and crisis phases influence the employment of the issue framing and strategy framing. For democratic countries, the more involved they are in the conflict, the more prominent strategy framing was in their coverage of the trade conflict; the inverse was observed for one-party dominant systems. Strategy framing that considers countries as contenders is more prevalent than the sub-frame that focuses on individual politicians. The presence of national-versus-personal level strategy framing was more balanced for directly involved countries than indirectly involved countries since news from directly involved countries accords relatively more space to politicians' personal strategy. [ABSTRACT FROM AUTHOR]

Reconfigurable silicon photonic devices are widely used in numerous emerging fields such as optical interconnects, photonic neural networks, quantum computing, and microwave photonics. Currently, phase change materials (PCMs) have been extensively investigated as promising candidates for building switching units due to their strong refractive index modulation. Here, nonvolatile multilevel switching of silicon photonic devices with Ge2Sb2Te5 (GST) is demonstrated with In2O3 transparent microheaters that are compatible with diverse material platforms. With GST integrated on the silicon photonic waveguides and Mach‐Zehnder interferometers (MZIs), repeatable and reversible multilevel modulation of GST is achieved by electro‐thermally induced phase transitions. Particularly, the segmented switching unit of In2O3 and GST is proposed and demonstrated to be capable of producing about one order of magnitude larger temperature gradient than that of the nonsegmented unit, resulting in up to 64 distinguishable switching levels of 6‐bit precision, and fine‐tuning of the switching voltage pulses is promising to push the precision even further, to 7‐bit, or 128 distinguishable switching levels. The capability of precise multilevel phase‐change modulation is crucial to further facilitate the development of nonvolatile reconfigurable switches and variable attenuation devices as building blocks in large‐scale programmable optoelectronic systems. [ABSTRACT FROM AUTHOR]