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The development of microwave absorbing materials with strong absorption capacity, wide bandwidth and light weight has always been a topic of concern. Herein, one-dimensional (1D) M (Co, Ni)@polyaniline (PANI) nanochains (NCs) with adjustable thickness have been successfully synthesized by reducing the mental ions under a parallel magnetic field, pretreating metal nanochains with KH550 and pre-oxidization of aniline monomer. It is found that Co has a more favorable absorption width for electromagnetic waves (EMW) and Ni aims at the absorption intensity. Furthermore, the effect of metal elements on adjusting impedance matching is more significant than their magnetic loss for composites. The minimum reflection loss (RLmin) of CoP2 can be up to -73.16 dB at 4.63 mm and the effective absorption bandwidth (EAB) is 4.98 GHz at 2.17 mm, while those of NiP2 are -65.06 dB at 3.88 mm and 5.02 GHz at 2.05 mm. The increase of PANI content can significantly reduce the matching thickness. And the RLmin of CoP3 and NiP3 can reach -58.72 dB at 2.32 mm and -65.96 dB at 1.59 mm, respectively. The absorption mechanism reveals that the matching thickness of the quarter-wavelength determines frequency location. And high absorption intensity is attributed to the synergistic effects of impedance matching, conduction loss, polarization loss, and magnetic loss. This work provides a theoretical basis for designing PANI or other conducting polymers coating magnetic nanochains for electromagnetic absorbing materials with strong absorption capacity, wide bandwidth and light weight.

Ni@PPy NCs/Ti3C2Tx ternary composites are successfully fabricated by the combination of solvothermal method, hydrothermal method and vacuum-assisted filtration, showing the optimum RLmin of −62.61 dB at 6.82 GHz and 2.71 mm.

To imitate the composition of natural bone and further improve the biological property of the materials, ZnO/hydroxyapatite/chitosan-polyethylene oxide@gelatin (ZnO/HAP/CS-PEO@GEL) composite scaffolds were developed. The core-shell structured chitosan-polyethylene oxide@gelatin (CS-PEO@GEL) nanofibers which could form the intramolecular hydrogen bond and achieve an Arg-Gly-Asp (RGD) polymer were first prepared by coaxial electrospinning to mimic the extracellular matrix. To further enhance biological activity, hydroxyapatite (HAP) was grown on the surface of the CS-PEO@GEL nanofibers using chemical deposition and ZnO particles were then evenly distributed on the surface of the above composite materials using RF magnetron sputtering. The SEM results showed that chemical deposition and magnetron sputtering did not destroy the three-dimensional architecture of materials, which was beneficial to cell growth. The cell compatibility and proliferation of MG-63 cells on ZnO/HAP/CS-PEO@GEL composite scaffolds were superior to those on CS-PEO@GEL and HAP/CS-PEO@GEL composite scaffolds. An appropriate amount of ZnO sputtering could promote the adhesion of cells on the composite nanofibers. The structure of bone tissue could be better simulated both in composition and in the microenvironment, which provided a suitable environment for cell growth and promoted the proliferation of MG-63 cells. The biomimetic ZnO/HAP/CS-PEO@GEL composite scaffolds were promising materials for bone tissue engineering.

Alexithymia is a common, but less-recognized affective deficit in patients with schizophrenia. To date, no definitive conclusions have been drawn about the relationship between alexithymia and the clinical symptoms or their clinical correlates, particularly in stable patients with schizophrenia. The purpose of this study was to investigate the link between alexithymia and psychopathological symptoms, as well as any associated correlates, in stable patients with schizophrenia. A total of 435 Chinese patients with schizophrenia were recruited. The Positive and Negative Symptoms Scale (PANSS) was used to evaluate each patient’s psychopathological symptoms. The Toronto Alexithymia Scale (TAS-20) was used to measure alexithymia. The percentage of alexithymia was 35.2% in stable patients with schizophrenia. Compared to non-alexithymia patients, patients with alexithymia had higher PANSS total scores, negative subscores, depressive subscores, and cognitive subscores (all p β = 0.274, t = 3.198, p = 0.001) and PANSS depressive subscores (β = 0.366, t = 2.500, p = 0.013). Education years (β = – 0.453, t = – 2.824, p = 0.005) was negatively associated with TAS-20 total scores. Our results suggest that the percentage of alexithymia was relatively higher in stable patients with schizophrenia. Education levels, negative symptoms, and depressive symptoms were independently associated with alexithymia in this specific population.

The fusiform g-C3N4/CaTiO3 nano-heterojunctions is synthesized via simple preparation using the hydrothermal co-deposition method. The results of morphology and structure imply that the g-C3N4 has deposited on the surface of fusiform CaTiO3 successfully, and the photocatalytic activity of the g-C3N4/CaTiO3 nano-heterojunctions exhibits a remarkably enhancement of 18 times than that of the unmodified sample. Further, proved by the transient photocurrent, PL, EIS and Motty-Scotty plots, the photocatalytic hydrogen production enhancement could be ascribed to the nano-heterojunction at the interface.

Accurate distinguish of cancer cells through fluorescence plays an important role in cancer diagnosis. Here we synthesized a blue fluorescent nitrogen-doped graphene quantum dots (N-GQDs) from citric acid and diethylamine via one-step hydrothermal synthesis method which was simple and quick to avoid by-products, and highlighted the binding sites to achieve precise combination. Due to the nitrogen element doping, amide II bond was amply obtained and abundant binding sites were provided for hyaluronic acid (HA) conjugation. N-GQDs solution with different pH value was then conjugated to HA via an amide bond for the recognition of human breast cancer cells (MCF-7 cells), and the formation of amide bond was more favorable under alkaline conditions. HA conjugated N-GQDs (HA-N-GQDs) were combined with CD44 which was over expressed on the surface of MCF-7 cells, resulting in MCF-7 cells performing stronger fluorescence. HA-N-GQDs showed high fluorescence, low toxicity, and good cytocompatibility, which held it play a role in fluorescence imaging for accurate identification of cancer cells.

A new joint algorithm is proposed to resolve the contradiction between algorithm complexity and performance in multiple input multiple output-orthogonal frequency division multiplexing (MIMO-OFDM) system. Using the hierarchical structure of the MIMO-OFDM systems, channel estimation and signal detection are alternately performed iteratively. Firstly, to reduce the complexity of channel estimation algorithm, an improved minimum mean squared error (MMSE) channel estimation algorithm is proposed. Then, zero force-successive interference cancellation (ZF-SIC) and MMSE-SIC are used in the joint algorithm as signal detection algorithms. Simulation results show that the new algorithm can obtain good BER performance under single path QPSK and single path 16 QAM simulation conditions. Compared with the existing joint algorithms, the new algorithm can make full use of system’s space resources and ensure the requirements of algorithm complexity and system performance.

Most of the existing routing protocols designed for LEO satellite networks assume that links are bi-directional symmetric links, which is in contradiction with appearance of Uni-directional link. Those protocols may decrease their performance or at worst cannot establish any path under Uni-directional links existence. In this paper, we will present an efficient routing protocol for LEO satellite networks with Uni-directional links. However, using Uni-directional link introduces new problems such as detection of link disconnection. In order to solve these problems, we employ the group strategy and parallel computing. Simulation results show that more packets could be delivered than Datagram Routing Algorithm (DRA) with pruning Uni-directional links. It is also shown that average end-to-end delay can be decreased in some extent by using group strategy and parallel computing.

This paper reports the preparation and application of folic acid-conjugated nitrogen-doped graphene quantum dots (N-GQDs) as a fluorescent diagnostic material for MCF-7 cells of breast cancer. N-GQDs were prepared by a hydrothermal method using citric acid as the carbon source and diethylamine as the nitrogen source. The doping of different amounts of nitrogen content was effectively controlled by diethylamine. As the amount of nitrogen increased, more binding sites on the N-GQDs were supplied to the folic acid. Laser confocal scanning microscopy showed that increased folic acid binding facilitated the recognition of and entry to cancer cells, which made the labeled cells emit a stronger fluorescence and thus the cancer cells could be better detected. Cytotoxicity tests showed that the material was of low cytotoxicity, making it a promising prospect for fluorescent probes.

The nitrogen-doped graphene quantum dot conjugated indomethacin (N-GQD-IDM) was synthesized by an amide reaction. The results of FTIR indicated that the synthesis of N-GQD-IDM was successful. It was then co-cultured with MCF-7 cells, and obvious fluorescence was observed under a laser confocal scanning microscope. With the increase of incubation time, the material accumulated significantly in the cells and the fluorescence intensity of the cells was slightly improved. This compound could be suggested as a promising fluorescent probe in cancer cell labeling.

The CdS/Ni3S2 heterojunction is prepared by a two-step hydrothermal method. The structure and crystalline phase are proved by SEM, TEM and XRD. The photocatalytic hydrogen production performance of the CdS/Ni3S2 heterojunction exhibits about ∼24 times enhancement that of pure CdS. It may be ascribed to the CdS with narrow band gap could increase the solar utilization. What’s more, the Ni3S2 with quick photon-generated electrons transferring could improve the separation of photon-generated carriers.

Polycrystalline Si 1 − x Cr x thin films have been prepared by magnetron sputtering followed by rapid thermal annealing (RTA) for crystallization. RTA was performed at 800 °C for 5 min, 1200 °C for 30 s and 1200 °C for 2 min, in a N 2 flow. The magnetic hysteresis loops were observed at room temperature in all the samples except for RTA at 800 °C for 5 min, and the annealing caused the decrease of saturation magnetization relative to the as-grown film. X-ray diffraction spectra and Raman spectra showed that the annealing process lead the deposited amorphous film to be crystallized and CrSi 2 phase formed. The magnetism of the films was determined by the competition between crystallinity and precipitation of diamagnetic CrSi 2 phase.