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Given tunable hybridization structures in solid solutions, fascinating electromagnetic (EM) properties can be achieved for regulating EM wave (EMW) absorption. Herein, a novel metal–organic cooperative interactions method is proposed to manipulate the vacancy, interstitial, substitutional, and heterointerface structures in molybdenum disulfide (MoS2) solid solution simultaneously, thence meeting the synergistic polarization loss on various point and face sites. Assisted by the coordination between Cu2+ and polydopamine (PDA), the effect of Cu modification on MoS2 is highly improved, which further lead to polarization loss on S vacancy, interstitial Cu, substitutional N, and heterointerface between carbon and MoS2. Contributing to the synergetic effect among multiple polarizations, the Cu/C@MoS2 solid solution exhibit ultrahigh EMW absorption performance, of which EMA with twice PDA delivers the effective absorption bandwidth of 7.12 GHz and minimum reflection loss of −48.22 dB (2.5 mm). The energy attenuation of Cu/C@MoS2 improved almost 266.7% and 222.2% than C@MoS2 and Cu@MoS2, respectively. Finally, this work reveals the structural dependency of solid solution materials of EMW absorption and establishes an entirely new polarization loss model. [ABSTRACT FROM AUTHOR]

Designing and preparing hollow nanomaterials is one of the most feasible ways to obtain the high-performance electromagnetic wave absorber. To this end, Metal–organic frameworks (MOFs), featuring regular crystalline structures with coordinated metal nodes and organic linkers, have won the widespread attention. Here, the recent progress in the study of MOFs-derived hollow materials for electromagnetic wave absorption are summarized and discussed. Some remarkable examples in the synthesis of hollow structures from MOFs precursors are illustrated in terms of the preparation methods and structural architectures. Thereafter, their characteristics and advantages as electromagnetic wave absorber are analyzed and demonstrated. Finally, it summarizes the current achievements, limitations, and urgent challenges, and provides some views on potential solutions and possible future trends. [ABSTRACT FROM AUTHOR]

[Display omitted] • ZnO/Fe Schottky junctions were fabricated in Fe(CN) 6 3− ligand exchange method. • Rietveld refinement was employed on analyzing heterogenous interfacial structures. • Heterointerfaces with Schottky contacts can be regarded as effective polar interfaces. • The f E of S3 reached 4.88 GHz with RL min of –33.36 dB. Various types of polycrystals have been regarded as excellent electromagnetic (EM) microwave absorbents, while differentiated heterointerfaces among grains usually manipulate conductive loss and polarization relaxation, especially interfacial polarization. Herein, polar facets that dominated the optimization of EM attenuation were clarified by carefully designing polycrystalline Schottky junctions with metal–semiconductor contacts for the first time. An ingenious ligand exchange technique was utilized to construct Zn-MOF (ZIF-L) precursors for Fe-ZnO polycrystals, in which Fe-containing Fe(CN) 6 3− etching ligand acted as metallic source in Schottky junctions. By adjusting the Schottky contacts in polycrystals, the enhanced grain boundaries mainly induced stronger interfacial polarization and affected the microcurrent lightly. This is because Schottky barriers can cause local charge accumulation on heterointerfaces for polarization relaxation. Additionally, the coexistence of Zn and O vacancies brought a lot of lattice defects and distortions for dipole polarization. Thus, optimal EM wave absorbability was obtained by polycrystals with 8 h ligand exchange and an effective absorption band reaching 4.88 GHz. This work can provide guidance for designing advanced polycrystalline EM absorption materials and also highlight the mechanism and requirement of Schottky junctions dominating polarization. [ABSTRACT FROM AUTHOR]

West Nile virus (WNV) was first isolated in mainland China from mosquitoes in Jiashi County, Kashgar Region, Xinjiang in 2011, following local outbreaks of viral meningitis and encephalitis caused by WNV. To elaborate the epidemiological characteristics of the WNV, surveillance of WNV infection in Kashgar Region, Xinjiang from 2013 to 2016 were carried out. Blood and CSF samples from surveillance human cases, blood of domestic chicken, cattle, sheep and mosquitoes in Kashgar Region were collected and detected. There were human 65 WNV Immunoglobulin M (IgM) antibody positive cases by ELISA screening, 6 confirmed WNV cases by the plaque reduction neutralization test (PRNT) screening. These cases occurred mainly concentrated in August to September of each year, and most of them were males. WNV-neutralizing antibodies were detected in both chickens and sheep, and the positive rates of neutralizing antibodies were 15.5% and 1.78%, respectively. A total of 15,637 mosquitoes were collected in 2013–2016, with Culex pipiens as the dominant mosquito species. Four and 1 WNV-positive mosquito pools were detected by RT-qPCR in 2013 and 2016 respectively. From these data, we can confirm that Jiashi County may be a natural epidemic foci of WNV disease, the trend highlights the routine virology surveillance in WNV surveillance cases, mosquitoes and avian should be maintained and enhanced to provide to prediction and early warning of outbreak an epidemic of WNV in China. [ABSTRACT FROM AUTHOR]

[Display omitted] • Oriented object detection can determine the two-dimensional crystals size and shape. • Nucleation and growth models were estimated using the online data. • Image analysis was more sensitive and consistent in nucleation detection than FBRM. • Agglomeration level was quantified by classification. • Seed loading can affect agglomeration and nucleation level. Image analysis enables the estimation of critical process properties such as crystal size, morphology, and crystallization kinetics. Despite the rich image information, the lack of a robust image analysis technique has been an obstacle to promote its applications. In this work, an automated image analysis technique that combines the state-of-the-art oriented object detection model, S 2 A-Net , was developed for in situ estimation of the two-dimensional crystal size distribution (CSD) and the crystal counts. The model was trained to detect and classify both crystals and clusters to enable quantification of the extent of agglomeration and exclude unreliable detections. The effectiveness and robustness of extracting size and aspect ratio at various image complexities were verified by comparing with the focused beam reflective measurement (FBRM) and manually analyzed images in the experimental studies for taurine batch cooling crystallization with different seed loadings. An on-line calibration strategy for solute concentration measurement with Raman spectroscopy was introduced to eliminate the dedicated calibration experiments. The secondary nucleation and growth rate kinetics were evaluated from the on-line measurements and validated by numerical simulation. The proposed method provides a novel PAT strategy that enables accurate two-dimensional size measurement and shape characterization for online monitoring and control of a solution crystallization process. [ABSTRACT FROM AUTHOR]

High propagation delays cause message collisions at intended nodes, which seriously affects network performance. In this paper, we consider the transmission scheduling problem of messages with specified transmission requirements, which is ignored by most MAC protocols of Underwater Acoustic Networks (UWANs). We focus on the actual applications of UWANs and adopt time-domain interference alignment to design a scheduling algorithm (TDIA-MAC). Firstly, we study the nature and the existence conditions of perfect scheduling. Secondly, we analyze the constraints required for feasible transmissions and design the value function to evaluate feasible transmissions. The optimal decision is selected from feasible transmissions by the value function. The algorithm meets the message transmission requirements in practical applications and ensures that multiple nodes can work simultaneously without conflicts. Finally, we simulate the proposed algorithm under two settings of varying offered traffic and the number of nodes. The results show that the TDIA-MAC outperforms the other three algorithms in terms of throughput, successful delivery ratio, and fairness under varying offered traffic and the number of nodes. [ABSTRACT FROM AUTHOR]