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Acta Metallurgica Sinica(English Letters) 2021年第4期34卷 445-454页

作者： Chenliang Chu Weiping Chen Zhen Chen Zhenfei Jiang Hao Wang Zhiqiang Fu Guangdong Key Laboratory for Advanced Metallic Materials Processing South China University of TechnologyGuangzhou 510640China Shantou Technician College Shantou 515041China

The present work reports a systematic investigation on phase evolution,microstructure and microstructure-property relationship of two typical face-centered cubic(FCC)structured high-entropy alloys(HEAs),FeNiCoCr and FeNiCoCrMn,prepared via mechanical alloying(MA)followed by spark plasma sintering(SPS).Following 50 h of MA,the two HEAs consisted of a mixture of FCC and body-centered cubic phases.Following SPS,the bulk FeNiCoCr alloy showed a primary FCC phase with a small amount of Cr_(23)C_(6) and Cr_(2)O_(3) contaminants,while the bulk FeNiCoCrMn alloy was composed of a primary FCC phase with some(Cr,Mn)23C6 and MnCr_(2)O_(4) contaminants.The average grain size of the primary FCC phase in the bulk FeNiCoCr alloy was~416 nm,while that of the primary FCC phase in the bulk FeNiCoCrMn alloy was~547 nm.The yield strength,compressive strength and strain-to-failure of the bulk FeNiCoCr alloy are 1525 MPa,1987 MPa and 24.4%,respectively,whereas those of the bulk FeNiCoCrMn alloy are 1329 MPa,1761 MPa and 21.9%,respectively.It suggests that the bulk FeNiCoCrMn exhibited lower strength and plasticity in comparison with the bulk FeNiCoCr alloy.Clearly,the smaller grain size of the primary FCC phase in the FeNiCoCr alloy is mainly responsible for the better mechanical performance.

关键词： High-entropy alloy Mechanical alloying Microstructure Strengthening Contaminants

Structure and Activity of a New Sapogenin from Chlorophytum laxum R. Br.

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Chemical Research in Chinese Universities 2018年第5期34卷 732-735页

作者： chu chenliang CUI Ting LI Sida ZHAN Ruoting GAO Youheng School of Pharmaceutical Sciences Guangzhou University of Chinese Medicine Guangzhou 510006 P. R. China

A new steroidal sapogotin named 25-R-spirosta-3,5-dien-12β-ol（1） was isolated from the dried roots of Chlorophytum laxum R. Br. along with five known compounds, namely, diosgenin（2）, stigmasterol（3）, β-sitosterols（4）, estigmasterol-3-O-β-D-glicopyranoside（5） and 3-O-β-authemisol（6）. The structure of compound 1 was elucidated by the analysis of IR, HRESI-MS, 1D and 2D NMR spectral data. Compounds 2--5 were isolated from Chlorophytum laxum R. Br. In addition, all the compounds were evaluated for cytotoxicity on the human nasopharyngeal carcinoma cancer cell line 5-8F. Among them, the newly identified 25-R-spirosta-3,5-dien-12β-ol（1） and diosgenin（2） exhibited high cytotoxicity on 5-8F cells, with IC50 values of 24.8 and 41.9 μmol/L, respectively.

关键词： Chlorophytum laxum R. Br. Steroidal sapogenin Cytotoxicity

Inhibitory Effect of Flavonoid Glycosides from Chlorophytum comosum on Nasopharyngeal Carcinoma 5-8F Cells and Its Mechanism

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Medicinal Plant 2024年第1期15卷 66-70页

作者： Chenliang Chu Xinchen WANG Kuan LU Liang QIN Lu JIN College of Food and Pharmaceutical Engineering Zhaoqing UniversityZhaoqing 526061China School of Pharmaceutical Sciences Sun Yat-sen UniversityGuangzhou 510006China

[Objectives]To study the inhibitory activity of two flavonoid glycosides isolated from Chlorophytum comosum Laxum R.Br on human nasopharyngeal carcinoma(NPC)cell line 5-8F in vitro and its mechanism.[Methods]The flavonoid glycosides were isolated and purified from the ethanol alcoholic extract of the roots of Liliaceae plant Chlorophytum comosum by silica gel column chromatography,macroporous resin column chromatography,Sephadex LH-20,and reverse column chromatography(ODS).The inhibitory activity of flavonoid glycosides on human nasopharyngeal carcinoma cells was analyzed by CCK-8 method,and the potential mechanism was preliminarily analyzed by molecular docking.[Results]Two flavonoid glycosides were identified as isovitexin 2″-0-rhamnoside and 7-2″-di-O-β-glucopyranosylisovitexin.Two flavonoid glycosides showed promising inhibitory effect on human nasopharyngeal carcinoma cell line 5-8F,with IC_(50) values of 24.8 and 27.5μmol/L,respectively.Molecular docking results showed that the potential targets of two flavonoid glycosides include CyclinD1,Bcl-2β-Catenin,ILK,TGF-β,in addition,two glycosides showed higher predicted binding affinity towards CyclinD1,which verifies the cytotoxicity of the two compounds on human nasopharyngeal carcinoma cell line 5-8F in vitro.[Conclusions]Two flavonoid glycosides are the active molecules in Chlorophytum comosum that can inhibit the proliferation of human nasopharyngeal carcinoma cells,and have the potential to be used in the research and development of anti nasopharyngeal carcinoma drugs.

关键词： Chlorophytum comosum Laxum R.Br. Flavonoid glycosides 5-8F cells Antitumor mechanism

A New Extrapolation Economy Cascadic Multigrid Method for Image Restoration Problems

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American Journal of Computational Mathematics 2023年第2期13卷 323-341页

作者： Zhaoteng chu Ziqi Yan chenliang Li School of Mathematics and Computational Science Guilin University of Electronics Technology Guilin China

In this paper, a new extrapolation economy cascadic multigrid method is proposed to solve the image restoration model. The new method combines the new extrapolation formula and quadratic interpolation to design a nonlinear prolongation operator, which provides more accurate initial values for the fine grid level. An edge preserving denoising operator is constructed to remove noise and preserve image edges. The local smoothing operator reduces the influence of staircase effect. The experiment results show that the new method not only improves the computational efficiency but also ensures good recovery quality.

关键词： Extrapolation Economy Cascadic Multigrid Method New Extrapolation Formula Edge Preserving Denoising Operator Local Smoothing Operator

粉末冶金(FeNiMnAl_(x))_(50)Cu_(50)中熵合金的微观组织与力学性能

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材料工程 2022年第10期50卷 55-62页

作者：陈维平陈焕达褚晨亮付志强华南理工大学广东省金属新材料制备与成形重点实验室广州510641

对物理法制备的再生铜合金粉末进一步合金化,通过机械合金化(MA)结合放电等离子烧结(SPS)的方法制备了(Fe_(40)Ni_(40)Mn_(20))_(50)Cu_(50),(Fe_(38)Ni_(38)Ni_(38)Mn_(19)Al_(5))_(50)Cu_(50),(Fe_(36)Ni_(36)Mn_(18)Al_(10))50 Cu_(50)和(Fe_(32)Ni_(32)Mn_(16)Al_(20))_(50)Cu_(50)四种中熵合金块体,并研究了Al元素的含量对中熵合金微观组织与力学性能的影响。结果表明:在高能球磨60 h之后合金粉末完成合金化,四种中熵合金粉末均形成单一FCC相的过饱和固溶体且有微量WC杂质。经SPS烧结后,(Fe_(40)Ni_(40)Mn_(20))_(50)Cu_(50),(Fe_(38)Ni_(38)Mn_(19)Al_(5))_(50)Cu_(50)和(Fe_(36)Ni_(36)Mn_(18)Al_(10))50 Cu_(50)形成了由富Cu的FCC1相和富Fe-Ni的FCC2相组成的双相FCC结构,并具有超细晶+微米晶的多尺度结构;而(Fe_(32)Ni_(32)Mn_(16)Al_(20))_(50)Cu_(50)由富Cu的FCC主相和少量富Fe-Mn的FCC2相及富Ni-Al的BCC相(B2)组成。随着Al含量的提高,四种中熵合金的塑性逐渐降低,而强度和硬度逐渐提高。(Fe_(40)Ni_(40)Mn_(20))_(50)Cu_(50)合金的压缩屈服强度、抗压强度和维氏硬度分别为878 MPa,1257 MPa和248.5HV。与(Fe_(40)Ni_(40)Mn_(20))_(50)Cu_(50)相比,(Fe_(32)Ni_(32)Mn_(16)Al_(20))_(50)Cu_(50)的压缩屈服强度和硬度分别提高了50.1%和50.4%,断裂应变由19.55%下降至8.31%。

关键词：中熵合金再生铜机械合金化放电等离子烧结微观组织力学性能

睡眠障碍对认知功能障碍及痴呆的影响及防治研究进展

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世界睡眠医学杂志 2022年第8期9卷 1433-1436页

作者：王馨晨路宽褚晨亮肇庆学院食品与制药工程学院制药工程系肇庆526061

睡眠障碍严重影响着神经系统的正常功能,尤其影响空间记忆、认知能力、理解力、学习能力等。本文通过对相关研究文献的整理,总结睡眠障碍影响认知功能和痴呆的相关机制,并在治疗方面总结中医、西医方面都比较有效的调整睡眠方法。旨在... 详细信息

睡眠障碍严重影响着神经系统的正常功能,尤其影响空间记忆、认知能力、理解力、学习能力等。本文通过对相关研究文献的整理,总结睡眠障碍影响认知功能和痴呆的相关机制,并在治疗方面总结中医、西医方面都比较有效的调整睡眠方法。旨在通过睡眠障碍对认知功能障碍和痴呆的影响进行研究,进一步梳理出可研究探讨的问题。

关键词：睡眠障碍认知功能障碍痴呆

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昆虫体内微生物多样性的影响因素研究进展

生物安全学报 2019年第3期28卷 170-176页

作者：魏晓莹郭晨亮褚栋青岛农业大学植物医学学院山东省植物病虫害综合防控重点实验室

昆虫体内的微生物种类繁多,在长期的协同进化中与其宿主昆虫形成了密切的共生关系。近年来,随着分子生物学技术的快速发展与应用,昆虫体内微生物多样性得到广泛的研究。本文综述了影响昆虫体内微生物多样性的各种因素。体内微生物多样... 详细信息

昆虫体内的微生物种类繁多,在长期的协同进化中与其宿主昆虫形成了密切的共生关系。近年来,随着分子生物学技术的快速发展与应用,昆虫体内微生物多样性得到广泛的研究。本文综述了影响昆虫体内微生物多样性的各种因素。体内微生物多样性除与昆虫种类相关外,还与昆虫自身因素(性别、发育龄期和种群)、生态因子(食物、温度、CO 2浓度和辐照)以及技术本身的局限性等方面密切相关。

关键词：昆虫体内微生物多样性影响因素

Wind disturbance compensated path-following control for fixed-wing UAVs in arbitrarily strong winds

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Chinese Journal of Aeronautics 2024年第2期37卷 431-445页

作者： Hao LU Lan GAO Yunda YAN Mingzhe HOU chenliang WANG Hangzhou Innovation Institute Beihang UniversityHangzhou 310051China School of Information Science and Technology Hangzhou Normal UniversityHangzhou 311121China Department of Computer Science University College LondonLondon WC1E 6BTUnited Kingdom Center for Control Theory and Guidance Technology Harbin Institute of TechnologyHarbin 150001China School of Automation Science and Electrical Engineering Beihang UniversityBeijing 100191China

Wind is the primary challenge for low-speed fixed-wing unmanned aerial vehicles to follow a predefined flight path.To cope with various wind conditions,this paper proposes a wind disturbance compensated path following control strategy where the wind disturbance estimate is incorporated with the nominal guiding vector field to provide the desired airspeed direction for the inner-loop.Since the control input vector for the outer-loop kinematic subsystem needs to satisfy a magnitude constraint,a scaling mechanism is introduced to tune the proportions of the compensation and nominal components.Moreover,an optimization problem is formulated to pursue a maximum wind compensation in strong winds,which can be solved analytically to yield two scaling factors.A cascaded inner-loop tracking controller is also designed to fulfill the outer-loop wind disturbance compensated guiding vector field.High-fidelity simulation results under sensor noises and realistic winds demonstrate that the proposed path following algorithm is less sensitive to sensor noises,achieves promising accuracy in normal winds,and mitigates the deviation from a desired path in wild winds.

关键词： Path following Guiding vector field Wind disturbance Disturbance rejection Fixed wings

A novel adaptive coordinated tracking control scheme for a morphing aircraft with telescopic wings

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Chinese Journal of Aeronautics 2024年第2期37卷 148-162页

作者： Enmei WANG Hao LU Jianchun ZHANG chenliang WANG Jianzhong QIAO Hangzhou Innovation Institute Beihang UniversityHangzhou 310051China School of Automation Science and Electrical Engineering Beihang UniversityBeijing 100191China

Inspired by flight biology,morphing flight technology has great potential to improve the adaptability and maneuverability of aircraft.This paper is devoted to the flight control problem of morphing aircraft,and aimed at safe and fuel-saving flight through morphing actively.Specifically,the longitudinal dynamics of a morphing aircraft with telescopic wings is modelled as a strict-feedback nonlinear system.Through fitting the expression of aerodynamic parameters by the mor-phing ratio,the model uncertainties induced by morphing errors are embedded in the dynamics.To meet the safety and fuel-saving requirements,an Adaptive Coordinated Tracking Control Scheme(ACTCS)is then proposed,which consists of a morphing control module and a tracking control module.For the morphing control module,an on-line morphing decision model is given in an optimization process with respect to the morphing ratio,and a second-order tracking filter is introduced to smooth the decision output and ensure the physical realizability.For the tracking control module,the novel adaptive controllers for the velocity and altitude subsystems are proposed based on the dynamic surface control method,in which adaptive mechanisms are designed to com-pensate for the model uncertainties.Finally,the proposed ACTCS is simulated in nine different cases of the test flight mission,to verify its effectiveness,robustness and fuel-saving effect.

关键词： Morphing aircraft Adaptive tracking control Morphing decision Dynamic surface control Morphing error

Special Issue of Single-atom Catalysis

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Chemical Research in Chinese Universities 2022年第5期38卷 I0001-I0004页

作者： WU Yuen SU chenliang WANG Yanggang University of Science and Technology of China Hefei 230026P.R.China Shenzhen University Shenzhen 518060P.R.China Southern University of Science and Technology Shenzhen 518055P.R.China

Single-atom catalysts(SACs)are a new type of heterogeneous catalysts formed by isolated metal atoms anchored on kinds of substrates.SACs are distinctly distinguished from traditional catalysts by characterizing with unique electronic structure,quantum size effect and unsaturated coordination environment,etc.,which brought subverted effects on traditional catalytic fields once upon the emergence.The unique chemical and physical properties impart SACs with outstanding catalytic performance,embodying nearly 1o0%atom utilization,high catalytic activity and excellent durability.SACs invariably have been the"hotspot"in catalysis research field during the last decade,shining brilliantly in applications of electro-,photo-and thermal catalysis.In particular,the advent of SACs points towards a possibility of the substantial cost reduction of precious metal catalysts in the future.This themed issue selected advanced studies on design,synthesis,characterization,and application of SACs,dedicating to assisting readers in a comprehensively and in-depth understanding of SACs.

关键词： durability catalysis invar