Absorbers with lightweight, low filler loading and broad absorption band are highly desirable for electromagnetic wave absorption field. Here, hollow Co1–xS microspheres constructed by nanosheets are ...fabricated via a facile synthetic method based on hydrothermal route. As an efficient wave absorber, the Co1–xS hollow spheres demonstrate excellent microwave absorption performance. With a weight content of only 3 wt%, the maximum reflection loss (RL) can reach as strong as −46.1 dB at 13.92 GHz and its qualified frequency bandwidth (with RL value over −10 dB) remarkably achieves 5.6 GHz, covering 35% of the entire measured bandwidth. In addition, compared with other cobalt sulfides (such as CoS2 and Co9S8), the Co1–xS microspheres with hollow structure exhibit more superior absorption intensity and broader qualified bandwidth. Therefore, this work provides a promising approach for the design and synthesis of hollow Co1–xS microspheres with lightweight and high‐performance microwave absorption.
The hollow Co1–xS microspheres with understanding microwave absorption performance are successfully fabricated through a facile hydrothermal route. The RLmax can reach to −46.1 dB at 13.92 GHz with an ultralow filler loading (3 wt%) and the effective frequency bandwidth is up to 5.6 GHz. Moreover, the possible wave absorption mechanism is also depicted comprehensively in this article.
Abstract
N
‐(
α
‐alkoxyalkyl)benzotriazoles are of great importance for biochemical and antitumor activity. A feasible protocol has been developed for the synthesis of
N
‐(
α
...‐alkoxyalkyl)benzotriazoles using azoles, aldehydes and alcohols as substrates under electrochemical conditions. The reaction is carried out under acid catalyst‐ and oxidant‐free conditions, so that a variety of synthetically useful nitrogen heterocyclic derivatives can be obtained. More meaningfully, a gram‐scale synthetic approach was employed to demonstrate the scale‐up applicability of this transformation.
This paper presents a molecular dynamics analysis of a bimodal nanocrystalline Cu-Ag alloy based on a scaling method. This method generates grain boundary affect zone (GBZA) of a bimodal ...nanocrystalline Cu-Ag alloy with a bimodal structure by isometric scaling of voronoi boundary vertices. Based on molecular dynamics simulation, the uniaxial tensile tests of bimodal nanocrystalline Cu-Ag alloy have been carried out, and its deformations under different strain conditions are studied while the influences of this deformation on its properties are analyzed. The effect of the coarse grain size of the atoms on the mechanical properties of the alloy has been investigated in previous experimental studies. In this thesis, we will further investigate the effect of the silver atomic composition content of the alloy matrix on its mechanical properties. By observing the internal microstructure of the experimental samples undergoing dislocation movements, it has been found that changing the Ag atomic composition content of the matrix gives feedback on the properties of the material. The specific manifestations of the influence of these variables on the dislocation activity of bimodal nanocrystalline Cu-Ag alloys and the corresponding deformation mechanisms hidden behind them are explored in detail.
The three-dimensional (3D) MoS2 hierarchical nanospheres which assembled spontaneously by two-dimensional (2D) lamina have been successfully designed and fabricated in large scale via a simple ...hydrothermal process. Subsequently, the electromagnetic wave absorption properties of hierarchical MoS2 nanospheres compounded with polyvinylidene fluoride (PVDF) were investigated in a broad frequency range of 2–40 GHz. The results indicated that the MoS2/PVDF nanocomposites possess adjustable and enhanced wave absorption performance. Furthermore, the MA performance can be effectively tuned by the absorber’s thickness and filler content. In addition, the peculiar hierarchical nanostructure of MoS2 is beneficial to microwave absorption property compared with the bulk MoS2 and micrometer-sized MoS2. Moreover, the main microwave absorption mechanism including various polarization, destructive interference theory, and multiple reflection has been described in detail.
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•Sequential steps in rice cake hydrolysis are quantified.•The observed hydrolysis rates are related to processing methods.•Rice cakes have better prebiotic effects than inulin.
Highly ...resistant starch rice (HRSR) is of particular interest in terms of its capacity to deliver short-chain fatty acids (SCFAs) to the colon in the prevention of diabetes mellitus and obesity. In this study, HRSR was processed into cooked rice, rice milk, rice cake, and rice popcorn, and the in vitro digestion and fermentation processes were monitored. The results showed that the starch digestibility of the four samples conformed to a first-order two-phase equation, and the resistant starch content of rice cake was the highest (11.98%). Compared with inulin, rice cake had a slower fermentation rate, and the butyrate concentration increased by 67.85%. The abundances of Prevotellaceae, which promotes the synthesis of SCFAs, and anti-inflammatory Faecalibacterium increased. The abundances of Proteobacteria and Megamonas, markers of gut microbiota imbalance, decreased. The results might facilitate the design and production of functional food products for type 2 diabetic and obese patients and improving colonic health.
Abstract
Recent spacecraft observations have shown that magnetic reconnection occurs commonly in turbulent environments at shocks. At quasi-perpendicular shocks, magnetic field lines are bent by the ...back-streaming reflected ions, which form a current sheet in the foot region, and then electron-scale reconnection occurs when the current sheet is fragmented at the shock front. Here we study magnetic reconnection at a quasi-perpendicular shock by using a two-dimensional particle-in-cell simulation. Collective properties of the reconnection sites from the shock transition to the downstream region are analyzed by adopting a statistical approach to the simulation data. Reconnecting current sheets are found to be densely distributed near the shock front, with a reconnection electric field larger than those in the downstream region. By tracing a reconnection site from its formation until it is convected downstream, we show the reconnection proceeds intermittently after an active stage near the shock front. Our tracing further shows that, in addition to being originated from the shock front, reconnection in the downstream region can also occur locally, driven by turbulent flows therein. The results help us better understand the evolution of electron-scale reconnection at a perpendicular shock.
A model describing the wide variety of human behaviours called personality, is becoming increasingly popular among researchers due to the widespread availability of personal big data generated from ...the use of prevalent digital devices, e.g., smartphones and wearables. Such an approach can be used to model an individual and even digitally clone a person, e.g., a Cyber-I (cyber individual). This work is aimed at establishing a unique and comprehensive description for an individual to mesh with various personalized services and applications. An extensive research literature on or related to psychological modelling exists, i.e., into automatic personality computing. However, the integrity and accuracy of the results from current automatic personality computing is insufficient for the elaborate modeling in Cyber-I due to an insufficient number of data sources. To reach a comprehensive psychological description of a person, it is critical to bring in heterogeneous data sources that could provide plenty of personal data, i.e., the physiological data, and the Internet data. In addition, instead of calculating personality traits from personal data directly, an approach to a personality model derived from the theories of Carl Gustav Jung is used to measure a human subject's persona. Therefore, this research is focused on designing an archetype-based modeling of persona covering an individual's facets in different situations to approach a comprehensive personality model. Using personal big data to measure a specific persona in a certain scenario, our research is designed to ensure the accuracy and integrity of the generated personality model.
Summary
Rab GTPases are required for vesicle–vacuolar fusion during vacuolar biogenesis in fungi. To date, little is known about the biological functions of the Rab small GTPase components in ...Magnaporthe oryzae. In this study, we investigated MoYpt7 of M. oryzae, a homologue of the small Ras‐like GTPase Ypt7 in Saccharomyces cerevisiae. Cellular localization assays showed that MoYpt7 was predominantly localized to vacuolar membranes. Using a targeted gene disruption strategy, a ΔMoYPT7 mutant was generated that exhibited defects in mycelial growth and production of conidia. The conidia of the ΔMoYPT7 mutant were malformed and defective in the formation of appressoria. Consequently, the ΔMoYPT7 mutant failed to cause disease in rice and barley. Furthermore, the ΔMoYPT7 mutant showed impairment in autophagy, breached cell wall integrity, and higher sensitivity to both calcium and heavy metal stress. Transformants constitutively expressing an active MoYPT7 allele (MoYPT7‐CA, Gln67Leu) exhibited distinct phenotypes from the ΔMoYPT7 mutant. Expression of MoYPT7‐CA in MoYpt7 reduced pathogenicity and produced more appressoria‐forming single‐septum conidia. These results indicate that MoYPT7 is required for fungal morphogenesis, vacuole fusion, autophagy, stress resistance and pathogenicity in M. oryzae.
Abstract With the help of a two-dimensional particle-in-cell simulation model, we investigate the long-time evolution (near 100 Ω i 0 − 1 , where Ω i 0 is the ion gyrofrequency in the upstream) of a ...quasi-parallel shock. Some of the upstream ions are reflected by the shock front, and their interactions with the incident ions excite low-frequency magnetosonic waves in the upstream. Detailed analyses have shown that the dominant wave mode is caused by the resonant ion–ion beam instability, and the wavelength can reach tens of ion inertial lengths. Although these plasma waves are directed toward the upstream in the upstream plasma frame, they are brought by the incident plasma flow toward the shock front, and their amplitude is enhanced during the approaching. The interaction of the upstream plasma waves with the shock leads to the cyclic reformation of the shock front, and the reformation period is slightly larger than 10 Ω i 0 − 1 . When crossing the shock front, these large-amplitude plasma waves are compressed and evolve into current sheets in the transition region of the shock. At last, magnetic reconnection occurs in these current sheets, accompanying the generation of magnetic islands. Simultaneously, there still exist plasma waves of another kind, with the wavelength of several ion inertial lengths in the ramp of the shock, which are excited by the nonresonant ion–ion beam instability. The current sheets in the transition region are distorted and broken into several segments when the plasma waves of this kind are transmitted into the downstream, where magnetic reconnection and the generated islands have a much smaller size. No obvious ion flow can be observed around some X-lines produced in the magnetic reconnection, and this implies that electron-only reconnection may occur.
CSDE1 (cold shock domain containing E1) plays a key role in translational reprogramming, which determines the fate of a number of RNAs during biological processes. Interestingly, the role of CSDE1 is ...bidirectional. It not only promotes and represses the translation of RNAs but also increases and decreases the abundance of RNAs. However, the mechanisms underlying this phenomenon are still unknown. In this review, we propose a "protein-RNA connector" model to explain this bidirectional role and depict its three versions: sequential connection, mutual connection and facilitating connection. As described in this molecular model, CSDE1 binds to RNAs and cooperates with other protein regulators. CSDE1 connects with different RNAs and their regulators for different purposes. The triple complex of CSDE1, a regulator and an RNA reprograms translation in different directions for each transcript. Meanwhile, a number of recent studies have found important roles for CSDE1 in human diseases. This model will help us to understand the role of CSDE1 in translational reprogramming and human diseases. Video Abstract.
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