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The operation disturbance induced by the solar array drive system (SADS) and the residual vibration of solar array following the attitude adjustment of the spacecraft obviously affect the dynamics environment, quick stabilization, and attitude stability of the high-precision spacecraft. However, these two kinds of vibration disturbance are characterized by distinct vibration categories, direction of vibration, and modal shapes. A multi-degree-of-freedom vibration reduction strategy (VRS) was presented to improve the dynamic characteristics of SADS and then to weaken these disturbances synthetically in this paper. SADS applying this VRS was modeled based on the virtual work principle, and the influence of the stiffness and damping parameters of this VRS on the SADS dynamic characteristics was analyzed. Then a prototype of vibration reduction device (VRD) was designed and verified by disturbance characteristic and modal experiments. The results indicate that the equivalent stiffness of VRD is critical to the natural frequency of SADS and thus should be carefully deliberated to avoid resonance. The equivalent damping of VRD always has positive correlation with modal damping. A good performance up to 40% in terms of operation disturbance suppression and a greater than 56% decrease of the damping time for 99% residual vibration have been obtained.

Near-infrared (NIR) light accounts for about half of the solar spectrum, and the effective utilization of low-energy NIR light is an important but challenging task in the field of photocatalysis. Molecular semiconductor photocatalytic systems (MSPSs) are highly tunable, available and stable, and are considered to be one of the most promising ways to achieve efficient NIR hydrogen production. Here, we demonstrate efficient dual-excitation in MSPS consisting of ZnIn2S4−x (ZIS1−x) with sulfur vacancies and phytic acid nickel (PA-Ni), which differs from other NIR-responsive photosensitized systems. The system achieves a hydrogen evolution reaction (HER) of 119.85 μmol h−1 g−1 at λ > 800 nm illumination, which is an excellent performance among all reported NIR catalysts and even outperforms the noble metal catalysts when compared to the reported literature. The superior activity is attributed to the unique charge dynamics and higher carrier concentration of the system. This work demonstrates the potential of dual-excitation systems for efficient utilization of low-energy NIR light. [ABSTRACT FROM AUTHOR]

Triboelectric nanogenerators (TENGs) with exceptional advantages are imperative for the development of next-generation wearable devices. In this study, we present a waterproof, flexible, transparent and breathable TENG fabricated by a cost-effective method. The innovative triboelectric layer can fold over 180°, retaining 83% transmittance compared to air, and achieve a water contact angle of 109.3°. Notably, we enhanced the nitrocellulose/silicon resin-based TENG's (NC/Si RS-TENG) output performance by 450%. Additionally, we explored the TENG performance with shape-adjustable electrodes, revealing a 5300% attenuation ratio between the electrode area and the electrical output performance and providing an approach to enhance the wearing comfort of the device. Furthermore, we introduce a compact triboelectric sensor (TES) for human–machine interface, sport monitoring and speech recognition. These findings broaden the prospects of shape-adjustable electrode TES in various domains, underscoring their significance in both fundamental research and practical applications. [ABSTRACT FROM AUTHOR]

The world's first high‐fired glazes were made in China, probably in the 16th century BCE, based largely on siliceous clay and calcareous wood ash. By the Song Dynasty (960–1279), this technology was at its zenith and included blackware glazes that exhibited reddish‐brown single‐phase, micron‐scale ε‐Fe2O3 films on their surfaces. However, it has been difficult to synthesize and replicate this effect on a larger scale and to a higher degree of purity through modern synthetic methods. To fully understand this effect, a strategy that combines nanomaterial science methods and theoretical calculation has been developed to study the hare's fur glazes of Song Dynasty (960–1279) Jian wares. Through our study of the original Song glazes, we show that a high‐alumina clay was used in creating the glaze, which introduced Al into the ε‐Fe2O3 lattices, playing a crucial role in metastable crystal stabilization. The explanation of both Al‐doping from clay, combined with a new understanding of ancient but effective firing manipulation, may provide alternative approaches for materials synthesis. [ABSTRACT FROM AUTHOR]

Peanut (Arachis hypogaea L.) is one of the important cash crops in China, and about 40% of peanuts are used for food production. The sucrose content was positively correlated with the flavor and taste of peanut and its products, thus increasing sucrose content in kernel was significant for the promotion of peanut quality. In this study, two F2:3 populations (NYBPXSYT5-1 and 19-1934XJHT1) were constructed to investigate the genetic model of sucrose content, and analyze the correlations between sucrose content with oil content, protein content, and other seed traits. The results showed that the sucrose contents of peanut kernel in two populations were continuously distributed and abundantly varied, and the transgressive segregation phenomenon were observed. In the two populations, sucrose content was significantly negatively correlated with oil content but significantly positively correlated with protein content. However, the correlations between sucrose content and kernel length, kernel width, and 100-kernel weight were inconsistent. The genetic analysis in two populations showed that the sucrose content in peanut kernel was mainly regulated by two pairs of main genes with the additive effect and dominant effect. There was the interaction between the two main genes, as well as the additive effect. This study initially reveals the genetic regulation of sucrose content in peanut kernels, which is beneficial for the breeding of edible peanut varieties and the cultivation of special varieties. [ABSTRACT FROM AUTHOR]

Nanostructured transition metal nitrides (TMNs) have been considered as a promising substitute for precious metal catalysts toward ORR due to their multi-electron orbitals, metallic properties, and low cost. To design TMN catalysts with high catalytic activity toward ORR, the intrinsic features of the influencing factor on the catalytic activity toward ORR of nanostructured TMNs need to be investigated. In this paper, titanium nitride (TiN), zirconium nitride (ZrN), and hafnium nitride (HfN) nanoparticles (NPs) are highly efficient and synthesized in one step by the direct current arc plasma. TiN, ZrN, and HfN NPs with an oxidation layer are applied as the catalysts of hybrid sodium–air batteries (HSABs). The effect of the composition and structural attributes of TMNs on ORR catalysis is defined as follows: (i) composition effect. With the increase in the oxygen content, the catalytic ORR capability of TMNs decreases progressively due to the reduction in oxygen adsorption capacity; (ii) structure effect. The redistribution of the density of states (DOS) of ZrN indicates higher ORR activity than TiN and HfN. HSABs with ZrN exhibit an excellent cyclic stability up to 137 cycles (about 140 h), an outstanding rate performance, and a specific capacity of 2817 mAh·g−1 at 1.0 mA·cm−2. [ABSTRACT FROM AUTHOR]

In metal–air batteries, the integrated solid‐state cathode is considered a promising design because it can solve the problem of high interfacial resistance of conventional solid‐state cathodes. However, solid discharge products cannot be efficiently decomposed in an integrated solid‐state cathode, resulting in batteries that are unable to operate for long periods of time. Herein, an integrated solid‐state cathode (Gel‐Tempo cathode) of sodium–air batteries (SABs) capable of promoting efficient decomposition of discharge product Na2O2 is designed. The Gel‐Tempo cathode is synthesized by cationic–π interaction of redox mediator 2,2,6,6‐tetramethyl‐1‐piperidinyloxy (Tempo) and ionic liquid with carbon nanotubes. The Gel‐Tempo cathode serves multiple functions as a redox mediator, flame retardancy, and high stability to air. In quasi‐solid‐state SABs, the Gel‐Tempo cathode reduces overpotential to 1.15 V and improves coulomb efficiency to 84.5% (at a limited discharge capacity of 3000 mAh g−1) compared to gel cathodes. Experiments and density functional theory calculations indicate that Tempo significantly reduces the Gibbs free energy in the decomposition reaction of Na2O2, and high Tempo content is more conducive to enhancing the decomposition kinetics of Na2O2 and hence resulting in an ultra‐long cycle life (1746 h). This work is crucial to promote practical applications of SABs, providing guidelines for functionalization design of integrated solid‐state cathodes for metal–air batteries. [ABSTRACT FROM AUTHOR]

In order to understand pathogenicity of Athelia rolfsii to different peanut varieties, six strains with high, moderate and weak virulence were inoculated on resistant and susceptible varieties in the field, occurrence of disease was investigated every week after inoculation. The results showed that the optimal time for investigation was 14 days after inoculation. There was no significant difference in disease index among cultivars inoculated by highly virulent strains ZY2 and SQ1, and weakly virulent strain GP3-1, respectively, but there was significant difference of those inoculated by moderately virulent strains (HA, H1-3 and BL1-1). The disease indices of varieties by strain GP3-1 was low; and was high by strains ZY2 and SQ1. All tested peanut varieties were susceptible to the highly virulent strains ZY2 and SQl.The disease indices between resistant and susceptible varieties showed significant difference among moderately virulent strains. One peanut variety with broad-spectrum resistance to multiple moderately virulent strains was identified. [ABSTRACT FROM AUTHOR]

Low temperature is a significant abiotic stress factor that restrict the growth of peanuts, and breeding of cold-tolerant varieties is the most direct and effective approach to solve low temperature and cold damage. In this study, 372 peanut germplasm resources collected from home and abroad were used as research objects,and the yield correlation traits and qualities in Wuhan of the warm region and Kunming of the cold region were analyzed. The membership function method was used combined with chain cluster analysis to screen excellent cold tolerance resources, and the influence of cold and cool climate on yield correlation factors and quality was analyzed. Key cold resistance identification indicators were screened to identify and evaluate their cold resistance. The results showed that the plant, yield and quality of peanut were mainly affected by the temperature, light and accumulated temperature at the pod stage and the full fruit ripening stage: the higher temperature and accumulated temperature, longer light time result in the higher yield, oil content, protein and other content and also resulted in lower content of oleic acid, linoleic acid and sucrose. Tolerance of different materials to low temperature was different. The comprehensive cold resistance evaluation value (D) was clustered and analyzed, and 372 varieties were divided into 4 categories. Among them, Class I belonged to the strong cold resistant type with a total of two parts; Class II belongs to the cold-resistant type with a total of 86 varieties; Class III belongs to the non-cold-resistant type with a total of 280 varieties; Class IV is a sensitive type of varieties with a total of 4 varieties. Using multiple stepwise regression analysis method, the evaluation model of peanut field cold tolerance Y=-0.002+0.003X1+0.008X2+0.002X3+0.001X4 was established, and the relative hundred kernel weight, relative number of fruits per plant, relative plant height and relative yield per plant were screened out as the initial screening indicators of peanut field cold tolerance, which provided basic varieties and efficient identification methods for the cultivation of new varieties of peanut cold tolerance and related theoretical research. [ABSTRACT FROM AUTHOR]

Selecting the right cathode material is a key component to achieving high‐energy and long‐lifespan aqueous zinc‐ion batteries (AZIBs); however, the development of cathode materials still faces serious challenges due to the high polarization of Zn2+. In this work, MnV12O31·10H2O (MnVO) synthesized via a one‐step hydrothermal method is proposed as a promising cathode material for AZIBs. Because the stable layered structure and hieratical morphology of MnVO provide a large layer space for rapid ion transports, this material exhibits high specific capacity (433 mAh g−1 at 0.1 A g−1), an outstanding long‐term cyclability (5000 cycles at a current density of 3 A g−1), and an excellent energy density (454.65 Wh kg−1). To illustrate the intercalation mechanism, ex situ X‐Ray diffraction, Fourier transform infrared spectroscopy, and X‐ray photoelectron spectroscopy are adopted, uncovering an H+/Zn2+ dual‐cation co‐intercalation processes. In addition, density‐functional theory calculation analysis shows that MnVO has a delocalized electron cloud and the diffusion energy barrier of Zn2+ in MnVO is low, which promotes the Zn2+ transport and consequently improves the reversibility of the battery upon deep cycling. The key and enlightening insights are provided in the results for designing high‐performance vanadium‐oxide‐based cathode materials for AZIBs. [ABSTRACT FROM AUTHOR]