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Optimization of components and micromorphology regulation are shown to be effective in boosting electromagnetic wave absorption (EMWA). One approach to achieve this enhancement is by utilizing the polarization effects of heterogeneous interfaces. Herein, NiSe2‐CoSe2@C@MoSe2 composites derived from NiCo‐MOF‐74 are fabricated via a facile selenization reaction and subsequent hydrothermal method. By varying the mass ratios of NiSe2‐CoSe2@C and MoSe2, a series of NiSe2‐CoSe2@C@MoSe2 composites with hierarchical flower‐like core–shell structures are obtained. The EMWA properties of the composites display a trend of initially increasing and then decreasing with the increasing content of MoSe2. Interestingly, when the mass ratio of NiSe2‐CoSe2@C and MoSe2 is 3:2, the minimum reflection loss (RL) value is −50.10 dB and an effective absorption bandwidth (RL< −10 dB) value can reach 4.80 GHz (13.20–18.00 GHz). The remarkable EMWA capability can be ascribed to the synergy effects of conductive loss, polarization loss, and suitable impedance matching. This work establishes a new pathway for the synthesis of transition metal dichalcogenides‐based composites, which hold great promise as high‐performance materials for EMWA applications. [ABSTRACT FROM AUTHOR]

Rational design of the components and microstructure is regarded as an efficacious strategy for the high-performance electromagnetic wave absorbing (EMWA) materials. Herein, the CoTe2@MoS2 nanocomposites with CoTe2 nanorods and MoS2 nanosheets were synthesized via a hydrothermal method. The microstructure and composition of the samples were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), energy dispersive X-ray spectroscopy (EDS), transmission electron microscopy (TEM), and X-ray photoelectron spectroscopy (XPS). The CoTe2@MoS2 composite was composed of stacked CoTe2 as the core and intertwined MoS2 nanosheets as the shell. The electromagnetic parameters of the CoTe2@MoS2 composites were investigated by vector network analyzer (VNA). The EMWA property of the composite showed a trend of first increasing and then decreasing with the increasing content of MoS2. When the mass ratio of MoS2 and CoTe2 was 1:1, the CoTe2@MoS2 composite exhibited the minimum reflection loss value of −68.10 dB at 4.71 GHz, and the effective absorption bandwidth value might reach 4.64 GHz (13.08–17.72 GHz) at a matching thickness of 1.60 mm with filler loading of 50 wt.%. The extraordinary EMWA property was attributed to the optimized impedance matching, multiple scattering and reflections, dipole polarization, conductive loss, and interfacial polarization. Therefore, the present approach to the design of microstructure and interface engineering offers a crucial way to construct high-performance EMW absorbers. [ABSTRACT FROM AUTHOR]

Enzymes are commonly used as biocatalysts for various biological and chemical processes. However, some major drawbacks of free enzymes (e.g. poor reusability and instability) significantly restrict their industrial practices. How to overcome these weaknesses remain considerable challenges. Enzyme immobilization is one of the most effective ways to improve the reusability and stability of enzymes. Cross-linked enzyme aggregates (CLEAs) has been known as a novel and versatile carrier-free immobilization method. CLEAs is attractive due to its simplicity and robustness, without purification. It generally shows: high catalytic specificity and selectivity, good operational and storage stabilities, and good reusability. Moreover, co-immobilization of different kinds of enzymes can be acquired. These CLEAs advantages provide opportunities for further industrial applications. Herein, the preparation parameters of CLEAs were first summarized. Next, characterization of structural and catalytic properties, stability and reusability are also proposed. Finally, some important applications of this technique in: environmental protection, industrial chemistry, food industry, and pharmaceutical synthesis and delivery are introduced. Potential challenges and future research directions, such as improving cross-linking efficiency and internal mass transfer efficiency, are also presented. This implies that CLEAs provide an efficient and feasible technique to improve the properties of enzymes for use in the industry. [ABSTRACT FROM AUTHOR]

High-dose-rate brachytherapy (HDR-BT) has been shown to play an important role in the treatment of cervical cancer patients. The aim of this systematic review and meta-analysis was to compare the dose parameters and long-term effects of MRI-based, CT-based and hybrid imaging (MRI/CT)-based volumetric planning. A systematic search was conducted to identify the clinical studies of BT treatment on cervical cancer patients. After study selection, a total of 13 clinical studies were enrolled for further analysis. No obvious differences were observed among the treatment parameters and the patients included. In detail, no significant difference was observed among these three techniques of volumetric planning in the parameters of high-risk clinical target volume (HR-CTV), total dose of D90 or mean fraction dose of D90. Meanwhile, MRI-based planning was superior to CT-based treatment in the total dose D2cc to organs at risk (OAR) for the bladder, rectum and sigmoid. Furthermore, no significant difference was observed among MRI-, CT- or hybrid-based treatments with the mean fraction dose D2cc to OAR for the bladder, rectum or sigmoid. In conclusion, MRI provides good anatomical delineation of the relevant HR-CTV and OAR, and performed better in the analyses of dose parameters compared with CT. At least one MR image is required to assess the tumour extension, with clinical findings and MRI information facilitating much more accurate CT-based contouring. [ABSTRACT FROM AUTHOR]