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| 1 | Solvent-Free Synthesis of Ultrafine Tungsten Carbide Nanoparticles-Decorated Carbon Nanosheets for Microwave Absorption显示文摘Carbides/carbon composites are emerging as a new kind of binary dielectric systems with good microwave absorption performance.Herein,we obtain a series of tungsten carbide/carbon composites through a simple solvent-free strategy,where the solid mixture of dicyandiamide(DCA)and ammonium metatungstate(AM)is employed as the precursor.Ultrafine cubic WC1-x nanoparticles(3-4 nm)are in situ generated and uniformly dispersed on carbon nanosheets.This configuration overcomes some disadvantages of conventional carbides/carbon composites and is greatly helpful for electromagnetic dissipation.It is found that the weight ratio of DCA to AM can regulate chemical composition of these composites,while less impact on the average size of WC1-x nanoparticles.With the increase in carbon nanosheets,the relative complex permittivity and dielectric loss ability are constantly enhanced through conductive loss and polarization relaxation.The different dielectric properties endow these composites with distinguishable attenuation ability and impedance matching.When DCA/AM weight ratio is 6.0,the optimized composite can produce good microwave absorption performance,whose strongest reflection loss intensity reaches up to-55.6 dB at 17.5 GHz and qualified absorption bandwidth covers 3.6-18.0 GHz by manipulating the thickness from 1.0 to 5.0 mm.Such a performance is superior to many conventional carbides/carbon composites. | Yunlong Lian Binhua Han Dawei Liu Yahui Wang Honghong Zhao Ping Xu Xijiang Han Yunchen Du | 2020 | Nano-Micro Letters2020，12，11： | 7 |
| 2 | Advances in core–shell engineering of carbon-based composites for electromagnetic wave absorption显示文摘Electromagnetic(EM)absorption is paving the way to overcome the challenges related to conventional shielding strategy against EM pollution through sustainable energy dissipation.As characteristic functional media that can interact with electric or magnetic field branch,EM wave absorption materials(EWAMs)have received extensive attention and realized considerable development in the past two decades,where carbon-based composites are always considered as promising candidates for high-performance EMAWs due to their synergetic loss mechanism as well as diversified composition and microstructure design.Recent progress indicates that there is more and more interest in the fabrication of carbon-based composites with unique core–shell configuration.On one hand,core–shell configuration usually ensures good chemical homogeneity of final products and provides some positive protections for the components with susceptibility to corrosion,on the other hand,it creates enough heterogeneous interfaces between different EM components,which may bring enhanced polarization effect and intensify the consumption of EM energy.In this review,we firstly introduce EM wave absorption theory,and then highlight the advances of core–shell engineering in carbonbased composites in terms of built-in carbon cores and built-out carbon shells.Moreover,we also show some special core–shell carbon-based composites,including carbon/carbon composites,assembled composites,and decorated composites.After analyzing EM absorption performance of some representative composites,we further propose some challenges and perspectives on the development of core–shell carbon-based composites. | Lixue Gai Honghong Zhao Fengyuan Wang Pan Wang Yonglei Liu Xijiang Han Yunchen Du | 2022 | Nano Research2022，15，10： | 5 |
| 3 | The electromagnetic properties and microwave absorption of mesoporous carbon显示文摘 | Du Yunchen Liu Tao Yu Bin | 2012 | Mater Chem Phys2012，135，23： | 1 |
| 4 | Polymer-bubbling for one-step synthesis of three-dimensional cobalt/carbon foams against electromagnetic pollution显示文摘Constructing three-dimensional(3D)foam-like structure in magnetic metal/carbon composites is regarded as a promising pathway to reinforce their electromagnetic(EM)functions.Herein,a nitrateassisted polymer-bubbling strategy is reported for the synthesis of Co/carbon foams,which is simply accomplished by direct pyrolyzing the mixture of polyvinylpyrrolidone(PVP)and cobalt nitrate hexahydrate(Co(NO_(3))_(2)·6 H_(2) O).Co(NO_(3))_(2)·6H_(2)O not only plays as the source of Co nanoparticles,but also accounts for the formation of 3D microstructure through releasing gas.By manipulating the weight ratio of Co(NO_(3))_(2)·6H_(2)O to PVP,the chemical composition,microstructure,and EM properties of these composites can be easily regulated.When the weight ratio reaches 1.5,the resultant composite displays good microwave absorption performance,whose reflection loss intensity and effective absorption bandwidth are superior to those of many common Co/C composites.EM analysis reveals that such architecture is greatly helpful to establish cross-linked conductive networks in the wax matrix,resulting in powerful dielectric loss under low absorber loading.Meanwhile,3D microstructure is also beneficial for multiple reflections that equal to extend the transmission path of incident EM waves.Simple synthesis strategy and desirable properties of these magnetic carbon foams may render them as the low-cost substitute of 3D graphene for the application against EM pollution. | Fengyuan Wang Ping Xu Ning Shi Liru Cui Yahui Wang Dawei Liu Honghong Zhao Xijiang Han Yunchen Du | 2021 | Journal of Materials Science & Technology2021，，34： | 1 |
| 5 | Ordered mesoporous silica materials (SBA-15) with good heat-resistant magnetism显示文摘 | Yunchen Du Sen Liu Yanyan Ji Yonglai Zhang Ni Xiao Feng-Shou Xiao | 2008 | Journal of Magnetism and Magnetic Materials2008，，： | 1 |
| 6 | Shell thickness-dependent microwave absorption of core-shell Fe304@C composites显示文摘 | Du Yunchen Liu Wenwen Qiang Rong | 2014 | Applied Materials &Interfaces2014，6，12： | 1 |
| 7 | Molecular cloning,characterization and promoter analysis of LbgCWIN1 and its expression profiles in response to exogenous sucrose during in vitro bulblet initiation in lily显示文摘Lily(Lilium spp.) is an important ornamental flower, which is mainly propagated by bulbs. Cell wall invertases(CWINs), which catalyze the irreversibly conversion of sucrose into glucose and fructose in the extracellular space, are key enzymes participating in sucrose allocation in higher plants. Previous studies have shown that CWINs play an essential role in bulblet initiation process in bulbous crops, but the underlying molecular mechanism remains unclear. Here, a CWIN gene of Lilium brownii var. giganteum(Lbg) was identified and amplified from genomic DNA. Quantitative RT-PCR assays revealed that the expression level of LbgCWIN1 was highly upregulated exactly when the endogenous starch degraded in non-sucrose medium during in vitro bulblet initiation in Lbg. Phylogenetic relationship, motif, and domain analysis of LbgCWIN1 protein and CWINs in other plant species showed that all sequences of these CWIN proteins were highly conserved. The promoter sequence of LbgCWIN1 possessed a number of alpha-amylase-, phytohormone-, light-and stress-responsive cis-elements. Meanwhile, β-glucuronidase(GUS) assay showed that the 459 bp upstream fragment from the translational start site displayed maximal promoter activity. These results revealed that LbgCWIN1 might function in the process of in vitro bulblet initiation and be in the response to degradation of endogenous starch. | Cong Gao Shiqi Li Yunchen Xu Yue Liu Yiping Xia Ziming Ren Yun Wu | 2024 | Horticultural Plant Journal2024，10，2： | 0 |
| 8 | Optimization of Superconducting Lead Film Plating Process显示文摘By testing the Q value of superconducting sample chamber,the process of solution configuration,preservation,degradation recovery and surface treatment before and after chamber electroplating was optimized,which greatly improved the quality of superconducting lead film. | ZHENG Jian PENG Zhaohua LIU Yunchen | 2018 | 中国原子能科学研究院年报2018，，1： | 0 |
| 9 | TLE orbit determination using simplex method显示文摘Two-Line Element(TLE)datasets are the only orbital data source of Earth-orbiting space objects for many civil users for their research and applications.The datasets have uneven qualities that may affect the reliability of the propagated positions of space objects using a single TLE.The least squares approach to use multiple TLEs also suffers from the poor quality of some TLEs,and reliable error information cannot be available.This paper proposes a simplex algorithm to estimate an optimal TLE from multiple TLEs and obtain the uncertainty of each element.It is a derivative-free technique that can deal with various orbit types.Experiments have demonstrated that using the TLE estimated from the simplex method is more reliable,stable,and effective than those from the batch least squares method.As an application example,the optimal TLE and its uncertainty are used for predicting the fallen area,keeping the actual fallen site in the prediction areas. | Jinghong Liu Wanting Long Yunchen Wu Jin Xu Jizhang Sang Xiangxu Lei | 2023 | Geodesy and Geodynamics2023，14，5： | 0 |
| 10 | A multi-omic landscape of steatosis-to-NASH progression显示文摘Nonalcoholic steatohepatitis(NASH)has emerged as a major cause of liver failure and hepatocellular carcinoma.Investigation into the molecular mechanisms that underlie steatosis-to-NASH progression is key to understanding the development of NASH pathophysiology.Here,we present comprehensive multi-omic profiles of preclinical animal models to identify genes,non-coding RNAs,proteins,and plasma metabolites involved in this progression.In particular,by transcriptomics analysis,we identified Growth Differentiation Factor 3(GDF3)as a candidate noninvasive biomarker in NASH.Plasma GDF3 levels are associated with hepatic pathological features in patients with NASH,and differences in these levels provide a high diagnostic accuracy of NASH diagnosis(AUROC=0.90;95%confidence interval:0.85−0.95)with a good sensitivity(90.7%)and specificity(86.4%).In addition,by developing integrated proteomic-metabolomic datasets and performing a subsequent pharmacological intervention in a mouse model of NASH,we show that ferroptosis may be a potential target to treat NASH.Moreover,by using competing endogenous RNAs network analysis,we found that several miRNAs,including miR-582-5p and miR-292a-3p,and lncRNAs,including XLOC-085738 and XLOC-041531,are associated with steatosis-to-NASH progression.Collectively,our data provide a valuable resource into the molecular characterization of NASH progression,leading to the novel insight that GDF3 may be a potential noninvasive diagnostic biomarker for NASH while further showing that ferroptosis is a therapeutic target for the disease. | Liping Xiang Xiaoyan Li Yunchen Luo Bing Zhou Yuejun Liu Yao Li Duojiao Wu Lijing Jia Pei-Wu Zhu Ming-Hua Zheng Hua Wang Yan Lu | 2022 | Life Metabolism2022，1，3： | 0 |
| 11 | Emergent leader-follower relationship in networked multiagent systems显示文摘Understanding the collective dynamics of leader-follower systems is a crucial and challenging issue.Previous studies have a priori designated leaders.However,the leaderfollower relationship is self-organized in human society over time and social interactions[1]. | Jinzhuo LIU Chenyou FAN Yunchen PENG Jinze DU Zhen WANG Chen CHU | 2023 | Science China(Information Sciences)2023，66，12： | 0 |
| 12 | Underwater Sea Cucumber Target Detection Based on Edge-Enhanced Scaling YOLOv4显示文摘Sea cucumber detection is widely recognized as the key to automatic culture.The underwater light environment is complex and easily obscured by mud,sand,reefs,and other underwater organisms.To date,research on sea cucumber detection has mostly concentrated on the distinction between prospective objects and the background.However,the key to proper distinction is the effective extraction of sea cucumber feature information.In this study,the edge-enhanced scaling You Only Look Once-v4(YOLOv4)(ESYv4)was proposed for sea cucumber detection.By emphasizing the target features in a way that reduced the impact of different hues and brightness values underwater on the misjudgment of sea cucumbers,a bidirectional cascade network(BDCN)was used to extract the overall edge greyscale image in the image and add up the original RGB image as the detected input.Meanwhile,the YOLOv4 model for backbone detection is scaled,and the number of parameters is reduced to 48%of the original number of parameters.Validation results of 783images indicated that the detection precision of positive sea cucumber samples reached 0.941.This improvement reflects that the algorithm is more effective to improve the edge feature information of the target.It thus contributes to the automatic multi-objective detection of underwater sea cucumbers. | Ziting Zhang Hang Zhang Yue Wang Tonghai Liu Yuxiang He Yunchen Tian | 2023 | Journal of Beijing Institute of Technology2023，32，3： | 0 |
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