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Polymer-derived ceramic aerogels are promising materials for thermal insulation and microwave absorption in harsh environments because their microstructures can be controlled at the molecular level. Silicon oxycarbide (SiOC) aerogels are considered as potential high-temperature electromagnetic wave (EMW) absorbers, but their application range is limited by complex preparation process and unsatisfactory microwave-absorption performance. This paper reports a new SiC nanowire/SiOC composite aerogel (SCA) synthesized through the sol–gel process, environmental pressure drying, and high-temperature treatment. The SCA performance is adjusted by controlling the ratio of SiC nanowires, obtaining low thermal conductivities (0.04–0.042 W m−1 K−1) and excellent mechanical properties (4.37–5.45 MPa). Increasing the SiC nanowire content gradually increases the EMW absorption capacity of SCA. The optimal reflection loss is −53.64 dB and the effective absorption bandwidth is 3.88 GHz, substantially higher than that of SiOC aerogels. This high performance is mainly attributable to the appropriate impedance matching characteristics and strong polarization loss ability. Moreover, the performance of the composite aerogels was retained after long-term treatment in an air environment at 800 °C. SCA also exhibits excellent high-temperature insulation and flame retardancy. Owing to its light weight, strong microwave-absorption ability, good thermal insulation performance, and oxidation resistance, SCA is a highly promising alternative material for use in extreme environments. [ABSTRACT FROM AUTHOR]

Poor fracture toughness and calcium–magnesium–aluminum–silicate (CMAS) corrosion resistance adversely affect environmental barrier coatings (EBCs) during prolonged service. Herein, an in-situ nanostructured Lu 2 O 3 /Lu 2 SiO 5 composite EBC was successfully prepared using nanostructured Lu 2 SiO 5 feedstocks. The morphologies and phase structures of the Lu 2 SiO 5 feedstocks and the corresponding coating were thoroughly characterized. Additionally, the mechanism of the in suit reaction of the Lu 2 O 3 /Lu 2 SiO 5 composite EBC was examined. The results indicate that the nanostructured as-deposited EBC exhibits a bimodal and dual-phase structure. The nanostructured Lu 2 SiO 5 coating comprises melted lamellae and unmelted or partially melted particles. The phase structure of these unmelted or partially melted particles includes Lu 2 O 3 and X2-Lu 2 SiO 5. The Lu 2 O 3 nanoparticles are formed by the decomposition of Lu 2 SiO 5 during spraying, and their content can be controlled to <15 %, which can enhance the fracture toughness and CMAS corrosion resistance of the EBCs to some extent. [ABSTRACT FROM AUTHOR]

The conductive polymers PEDOT:PSS coated Li 1.20 [Mn 0.53 Ni 0.13 Co 0.13 Nb 0.01 O 2 cathode materials were synthesized via using the sol-gel method, followed by the wet solution process. And the X-ray diffraction (XRD), Rietveld refinement, Scanning electron microscopy (SEM), Transmission electron microscopy (TEM), X-ray photoelectron spectroscopy (XPS) were adopted to investigate the morphology and constituents of as-prepared cathode materials. The results demonstrated that a PEDOT:PSS layer was uniformly distributed on the surface of bulk Li 1.20 Mn 0.54 Ni 0.13 Co 0.13 O 2 with Nb5+ doping successfully. And the PEDOT:PSS surface coating and Nb5+ doping modifications showed a significant improvement on the electrochemical properties of cathode. In particular, the 2 wt% PEDOT:PSS coated Li 1.20 [Mn 0.53 Ni 0.13 Co 0.13 Nb 0.01 O 2 delivered a supernal discharge capacity of 145.6 mAhg−1 at 5C high rate and retained a high capacity retention of 90.8% after 200 cycles at 45 °C, which were more superior than those of the pristine cathode (90.2 mAhg−1 and 80.7%). The enhanced electrochemical properties could be attributed to the facilitation of Lithium ions diffusion, the lower cation mixing and restriction of the side reactions between cathode surfaces with electrolyte by the Nb5+ doping and PEDOT:PSS coating. The 2 wt % PEDOT:PSS coated Li 1.20 [Mn 0.53 Ni 0.13 Co 0.13 Nb 0.01 O 2 is covered by the PEDOT:PSS coating layer with a thickness of 20–30 nm. And after 200 cycles at 45 °C, the Li 1.20 [Mn 0.53 Ni 0.13 Co 0.13 Nb 0.01 O 2 and PEDOT:PSS coated Li 1.20 [Mn 0.53 Ni 0.13 Co 0.13 Nb 0.01 O 2 with the coating content of 1 wt%, 2 wt% and 3 wt% deliver the discharge capacity of 178.2, 192.7, 207.2 and 198.6 mA h g−1, corresponding to the capacity retention of 83.4%, 87.7%, 90.8% and 89.2, respectively. By contrast, the capacity of the pristine Li 1.20 Mn 0.54 Ni 0.13 Co 0.13 O 2 attenuates drastically from 202.3 mA h g−1 to 163.2 mA h g−1 at 0.5C rate, with only capacity retention of 80.7% left. Image 1 • The electrochemical properties of Li 1.20 Mn 0.54 Ni 0.13 Co 0.13 O 2 are enhanced by the PEDOT:PSS coating and Nb5+ doping. • The PEDOT:PSS coating layer could cover the cathode surface uniformly and efficiently resist against HF corrosion. • The Nb5+ doping can reduce the cation mixing and improve the high rate performance. • 2wt% PEDOT:PSS coated Li 1.20 [Mn 0.53 Ni 0.13 Co 0.13 Nb 0.01 O 2 expresses the outstanding electrochemical properties. [ABSTRACT FROM AUTHOR]

High-performance plasma-sprayed feedstocks are crucial in the fabrication of high-performance coatings. Thus far, rare-earth silicates have attracted considerable attention. As far as we know, nanostructured Lu 2 Si 2 O 7 feedstocks for plasma-sprayed environmental barrier coatings (EBCs) were prepared via nanopowder reconstruction herein for the first time. The microstructure of the Lu 2 Si 2 O 7 feedstocks was investigated comprehensively and their physical properties were characterized. The results show that the grain size of the spherical Lu 2 Si 2 O 7 feedstocks with a single phase is approximately 65 nm, with the median particle size being 43.69 μm. The apparent density and tap density of the feedstocks are 1.72 and 2.04 g/cm3, respectively. The as-prepared nanostructured Lu 2 Si 2 O 7 feedstocks are believed to be promising for advanced EBCs in the future. [ABSTRACT FROM AUTHOR]

• We presented a way to prevent wheat lodging: mixed cropping of two genotypes enhanced wheat lodging resistance. • The lodging can be inhibited by mixed cropping of lodging-resistant cultivars with lodging-susceptible cultivars. • Mixed cropping inhibited lodging via lodging-resistant cultivars providing support for lodging-susceptible cultivars. Lodging negatively affects wheat production worldwide. However, little is known about the potential of intercropping (different genotypes of wheat are planted in alternating rows) and mixed cropping of different genotypes to enhance the lodging resistance of wheat populations. In this study, a field experiment was conducted with two cultivars, 'Shannong8355' (SN8355, a lodging-resistant cultivar) and 'Shannong15' (SN15, a lodging-susceptible cultivar), to investigate the effect of these planting patterns on the occurrence of lodging in wheat and analyze the mechanism through which lodging resistance may be enhanced. Intercropping and mixed cropping of SN8355 with SN15 was shown to effectively reduce the occurrence of lodging in SN15, through SN8355 plants supporting SN15 plants and thereby inhibiting lodging of the composite population; the effect of mixed cropping was strongest. Furthermore, compared with the sole cropping and intercropping treatments, the mixed cropping of SN8355 and SN15 significantly improved the yield stability of wheat population. These results suggested that mixed cropping could inhibit the occurrence of lodging completely via lodging-resistant wheat cultivars providing both lateral and longitudinal support for lodging-susceptible cultivars, thus significantly enhancing the lodging resistance and yield stability of composite populations. The conclusion of this study could provide a theoretical basis to improve regulatory techniques for effectively inhibiting the occurrence of wheat lodging. [ABSTRACT FROM AUTHOR]

Abstract DOXC is one of the 2-oxoglutarate-dependent dioxygenases (2OGDs) classes, which is involved in the biosynthesis of colorful flavonoids and plant hormones. Safflower ( Carthamus tinctorius L.) is a commonly used plant with flavonoids. Herein, we focused on analyzing the characterization, transcript abundance, and correlation of DOXC-class 2OGDs in safflower with flavonoids for the first time. TBLASTN analysis showed that they were implicated in the biosynthetic pathway of ethylene (DOXC1 and DOXC2), indole-3-acetic acid (DOXC3, DOXC4, and DOXC5), flavonoids (DOXC6, DOXC7, and DOXC8), and scopolamine (DOXC9 and DOXC10). The transcript abundance of DOXC1, DOXC2, DOXC6, DOXC7, and DOXC10 response to methyl jasmonate (MeJA) in two safflower lines (orange-yellow-flowered safflower line with major quinochalcones and minor flavonols, white-flowered safflower line with major flavonols and without quinochalcones) had converse transcript level accumulation. Coexpression analyses displayed that the transcript level of DOXC1, DOXC2 and DOXC8 was positively correlated with hydroxysafflor yellow A, a major quinochalcone in orange-yellow-flowered safflower line. DOXC3, DOXC4, DOXC5, DOXC7, and DOXC9 displayed a marked positive correlation with kaempferol-3- O -β-D-glucoside, a main flavonols in white-flowered safflower line. The response models of DOXC3, DOXC4, DOXC5 and DOXC9 showed amazing similarity in different safflower line, but the correlations with flavonoids were actually quite distinct. In orange-yellow-flowered safflower line, they might be implicated in the rutinoside modification of kaempferol and quercetin, but their functions were different and diversity in white-flowered safflower line. In sum, ten DOXC-class 2OGDs from safflower displayed different sequence features. Simultaneously, their expression pattern in two safflower lines in response to MeJA treatment, as well as their correlation with flavonoids, was different. These results implied the diversification of DOXC-class 2OGDs is partly responsible for the diversity and complexity of specialized metabolites in different phenotypes and chemotypes of safflower lines. Highlights • 10 DOXC-Class 2OGDs were Identified and screened from safflower based on our EST database. • The analysis from TBLASTN showed that they were implicated in the biosynthetic pathway. • The transcript abundance of the 10 DOXC-class 2OGDs in two safflower lines had conversed accumulation. • Correlation between the transcript level of the 10 2OGDs and flavonoid accumulation were different in two safflower lines. • The diversification of the 2OGDs is partly responsible for the diversity and complexity of metabolites in safflower lines. [ABSTRACT FROM AUTHOR]