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Defence Technology（防务技术） 2024年第2期32卷 412-429页

作者： wenxue chen Yudong Hu Changsheng Gao Ruoming An School of Astronautics Harbin Institute of TechnologyHarbin 150001China

This paper investigates interception missiles’trajectory tracking guidance problem under wind field and external disturbances in the boost phase.Indeed,the velocity control in such trajectory tracking guidance systems of missiles is challenging.As our contribution,the velocity control channel is designed to deal with the intractable velocity problem and improve tracking accuracy.The global prescribed performance function,which guarantees the tracking error within the set range and the global convergence of the tracking guidance system,is first proposed based on the traditional PPF.Then,a tracking guidance strategy is derived using the integral sliding mode control techniques to make the sliding manifold and tracking errors converge to zero and avoid singularities.Meanwhile,an improved switching control law is introduced into the designed tracking guidance algorithm to deal with the chattering problem.A back propagation neural network(BPNN)extended state observer(BPNNESO)is employed in the inner loop to identify disturbances.The obtained results indicate that the proposed tracking guidance approach achieves the trajectory tracking guidance objective without and with disturbances and outperforms the existing tracking guidance schemes with the lowest tracking errors,convergence times,and overshoots.

关键词： BP network neural Integral sliding mode control(ISMC) Missile defense Prescribed performance function(PPF) State observer Tracking guidance system

A high-performance electrocatalyst for oxygen reduction derived from copolymer-anchored polyoxometalates

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Nano Research 2024年第6期17卷 5197-5205页

作者： Yue Du wenxue chen Zhiyi Zhong Zhixian Shi Yulin Zhang Xuanning chen Yisi Liu Dongbin Xiong Lina Zhou Zhenhui Liu Mingbo Zheng Hubei Key Laboratory of Photoelectric Materials and Devices&College of Material Science and Engineering Hubei Normal UniversityHuangshi 435002China College of Materials Science and Technology Nanjing University of Aeronautics and AstronauticsNanjing 210016China

The development and synthesis of cathode electrocatalysts with high activity and durable stability for metal-air batteries is an important challenge in the area of electrocatalysis.Herein,we introduce a novel in-situ nitriding and phosphating strategy for producing W_(3)N_(4)and WP from phosphotungstic acid(HPW)-polyaniline-phytic acid-Fe3+organic-inorganic hybrid material.The final material has a three-dimensional porous framework with W_(3)N_(4)-WP heterostructures embedded in the carbon matrix(W_(3)N_(4)-WP@NPC).As-made materials exhibit exceptional electrocatalytic performance for the oxygen reduction reaction(ORR),with a diffusion-limiting current density of 6.9 mA·cm^(−2)and a half-wave potential of 0.82 V.As a Zn-air primary cathode,the W_(3)N_(4)-WP@NPC assembled battery can provide a relatively high peak power density(194.2 mW·cm^(−2)).As a Zn-air secondary air-cathode,it has great cycling stability over 500 h.This work provides a simple and efficient method for rationally designing high-performance air cathodes from copolymer-anchored polyoxometalates.

关键词： W_(3)N_(4)-WP heterojunctions copolymer-anchored polyoxometalates oxygen reduction reaction Zn-air battery

A novel adaptive lateral reentry guidance algorithm with complex distributed no-fly zones constraints

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Chinese Journal of Aeronautics 2022年第7期35卷 128-143页

作者： Yudong HU Changsheng GAO Junlong LI Wuxing JING wenxue chen School of Astronautics Harbin Institute of TechnologyHarbin 150001China Beijing Institute of Electronic System Engineering China Aerospace Science and Industry CorporationBeijing 100854China

Aimed at complex distributed no-fly zones avoidance problems,a novel adaptive lateral reentry guidance algorithm is proposed.Firstly,by introducing the improved attractive and repulsive potential fields,an improved artificial potential field method is developed.Combined with the proposed judgment criterion for whether a no-fly zone has been avoided,the proposed improved artificial potential field method effectively solves the reference heading angle determination problem under the constraints of complex distributed no-fly zones.Then,based on the proposed no-fly zone’s threat quantitative evaluation method and the reference heading angle determined by the proposed improved artificial potential field method,the heading corridor is improved to increase its sensitivity to the threat changes of the no-fly zones.Finally,for satisfying the requirements of complex distributed no-fly zones avoidance,a novel guidance logic via improved heading corridor is proposed to update the reference heading corridor adaptively in real time according to the threat and constraint changes of the no-fly zones,and the bank reversal logic is employed to control the lateral motion.The simulation results for nominal and dispersed cases indicate that the proposed guidance algorithm has high robustness,stability,and applicability,and is feasible and effective to deal with the complex distributed no-fly zones avoidance problems.

关键词： Guidance strategy Heading corridor Hypersonic vehicles Improved artificial potential field Lateral reentry guidance Threat quantitative evaluation

One-step,in situ formation of WN-W_(2)C heterojunctions implanted on N doped carbon nanorods as efficient oxygen reduction catalyst for metal-air battery

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Nano Research 2023年第7期16卷 8773-8781页

作者： Yue Du wenxue chen Lina Zhou Rui Hu Shizhu Wang Xueqing Li Yunlong Xie Lun Yang Yisi Liu Zhenhui Liu Institute for Advanced Materials Hubei Normal UniversityHuangshi 435002China College of Material Science and Engineering Jiangsu Key Laboratory of Materials and Technology for Energy ConversionNanjing University of Aeronautics and AstronauticsNanjing 210016China

Transition metal nitrides and carbides have attracted intensive attentions in metal-air battery application due to their metallic electron transport behavior and high chemical stability toward the oxygen reduction reaction(ORR).Herein,the polyoxometalate@polyaniline composite derived WN-W_(2)C heterostructured composite(WN-W_(2)C@pDC)has been fabricated through an in situ nitriding-carbonization strategy,with WN-W_(2)C nanoparticles implanted on N doped carbon nanorods.Asfabricated WN-W_(2)C@pDC demonstrates prominent electrocatalytic performance towards ORR and excellent cycling stability in metal-air battery,which possesses positive half-wave potential and large diffusion limiting current density(0.81 V and 5.8 mA·cm^(-2)).Moreover,it demonstrates high peak power density of 157.4 mW·cm^(-2)as Al-air primary cathode and excellent stability at the discharge-charge test(>500 h)of Zn-air secondary battery.The excellent activity and durability of WNW_(2)C@pDC catalyst should be attributed to the combined effect of intimate WN-W_(2)C heterointerfaces,unique embedded nanoparticles structure,and excellent electrical media of N doped carbon,confirmed by a series of contrast experiments.

关键词： WN-W_(2)C heterojunctions polyoxometalate@polyaniline composite oxygen reduction reaction metal-air battery

Research on Pavement Roughness Based on the Laser Triangulation

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Photonic Sensors 2016年第2期6卷 177-180页

作者： wenxue chen Zhibin NI Xinhan HU Xiaofeng LU Equipment Academy of the Rocket Force Beijing 100094 China

人行道粗糙是为估价高速公路建设的最重要的因素之一。在这篇论文，我们选激光为三角测量测量人行道粗糙。激光三角测量的原则和配置被介绍。把技术基于这，道路表面的人行道粗糙被测量。测量结果在这篇论文被给。这个系统的测量范围是 ... 详细信息

人行道粗糙是为估价高速公路建设的最重要的因素之一。在这篇论文，我们选激光为三角测量测量人行道粗糙。激光三角测量的原则和配置被介绍。把技术基于这，道路表面的人行道粗糙被测量。测量结果在这篇论文被给。这个系统的测量范围是 50 m。这种技术的测量错误被分析。这种技术有重要意义在工作量的结束以后估价高速公路的质量。

关键词：路面平整度激光三角法激光三角测量质量评价公路施工测量范围测量误差高速公路

Dissolution kinetics of Si and Al from montmorillonite in carbonic acid solution

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International Journal of Coal Science & Technology 2014年第1期1卷 31-38页

作者： Xiaoming Ni Quanzhong Li wenxue chen State Key Laboratory Cultivation Base for Gas Geology and Gas Control Henan Polytechnic UniversityJiaozuo 454000China School of Energy Science and Engineering Henan Polytechnic UniversityJiaozuo 454000China School of Civil Engineering Henan Polytechnic UniversityJiaozuo 454000China

The reaction between carbonic acid and montmorillonite minerals was studied in order to provide a theoretical basis for analyzing changes in the physical properties of coal seams after CO_(2)injection and for optimizing CO_(2) pumping parameters.A single montmorillonite mineral of purity[90%was selected and subjected to reactions at 25,35,and 45℃in carbonic acid solutions of varying acidity.The Si and Al concentrations in the solutions and the structure and elemental compositions of the montmorillonite before and after the reactions were analyzed using a spectrophotometer,an X-ray diffractometer,and an energy-dispersive X-ray spectrometer;kinetic reaction models were established for the dissolution of Si and Al in carbonic acid solutions in order to estimate the apparent activation energy of Si dissolution under different acidity conditions.The results indicate that Al dissolved rapidly and soon reached solubility equilibrium.On the other hand,Si concentration in the solutions increased rapidly and then gradually declined with vibrations,with maximum values at 25,35,and 45℃,which were observed at approximately 96,72,and 48 h,respectively.In addition,Si dissolution fitted the diffusion-controlled reaction model well;as the pH value decreased,the apparent activation energy of Si dissolution decreased,and Si became easier to dissolve.Furthermore,it was concluded that as a weak acid,carbonic acid causes little damage to the mineral structure of montmorillonite.

关键词： Montmorillonite Carbonic acid solution Dissolution of Si and Al Reaction kinetics

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拦截高超声速滑翔飞行器:制导进展与展望

宇航学报 2024年第6期45卷 799-814页

作者：陈文雪胡玉东高长生荆武兴安若铭哈尔滨工业大学航天学院哈尔滨150001

聚焦于临近空间拦截制导关键技术,围绕中制导、中末制导交班及末制导等关键问题对临近空间拦截制导技术前景进行展望。首先对临近空间高超声速滑翔飞行器飞行特性进行仿真与分析,并给出防御系统在滑翔段拦截的优势所在;其次,围绕临近空... 详细信息

聚焦于临近空间拦截制导关键技术,围绕中制导、中末制导交班及末制导等关键问题对临近空间拦截制导技术前景进行展望。首先对临近空间高超声速滑翔飞行器飞行特性进行仿真与分析,并给出防御系统在滑翔段拦截的优势所在;其次,围绕临近空间拦截系统面对高超声速滑翔飞行器时存在的瓶颈进行探讨,并对中制导离线弹道生成与在线弹道生成、中末制导交班及末制导等关键技术相关研究进展进行梳理与总结;最后,结合当前研究进展、面临的挑战及未来临近空间拦截需求,研究分析临近空间拦截制导技术的发展趋势,为后续防御系统的发展提供参考。

关键词：临近空间拦截制导高超声速飞行器高动态机动目标防御技术

南水北调中线京石段闸门间歇关闭水力响应特性

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南水北调与水利科技（中英文） 2024年第3期22卷 427-435页

作者：雷毓灵崔巍王磊丁志楠穆祥鹏陈文学中国水利水电科学研究院流域水循环模拟与调控国家重点实验室北京100038

为减小闸门关闭引发的水位壅高,以南水北调中线工程京石段磁河闸至沙河北闸之间的渠池为研究对象,构建一维明渠非恒定渐变流仿真模型,比较分次间歇关闸与一次连续关闸,以及不同闸门间歇方案对闸前壅水峰值、水力振荡稳定时间的影响。研... 详细信息

为减小闸门关闭引发的水位壅高,以南水北调中线工程京石段磁河闸至沙河北闸之间的渠池为研究对象,构建一维明渠非恒定渐变流仿真模型,比较分次间歇关闸与一次连续关闸,以及不同闸门间歇方案对闸前壅水峰值、水力振荡稳定时间的影响。研究表明:分次间歇关闸可带来更低的闸前壅水水位和更短的水力振荡稳定时间;设置1次间歇相较于多次间歇可减小闸前壅水峰值,将间歇开始时刻设置在上游降水波即将传播至闸前的时刻、设置间歇时长略小于关闸总时间的1/2均可有效降低闸前壅水峰值,缩短稳定时间。闸门分次间歇关闭水力响应特性与水波运动规律紧密关联,合理设置间歇有助于在应急调控阶段减少事故造成的影响。

关键词：明渠水力学南水北调中线工程闸门分次间歇关闭水力振荡应急调度

Opportunities and challenges of CD47-targeted therapy in cancer immunotherapy

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Oncology Research 2024年第1期32卷 49-60页

作者： QIUQIANG chen XUEJUN GUO wenxue MA Key Laboratory for Translational Medicine The First Affiliated HospitalHuzhou University School of MedicineHuzhou313000China Department of Hematology Puyang Youtian General HospitalPuyang457001China Department of Medicine Moores Cancer CenterSanford Stem Cell InstituteUniversity of California San DiegoLa JollaSan Diego92093USA

Cancer immunotherapy has emerged as a promising strategy for the treatment of cancer,with the tumor microenvironment(TME)playing a pivotal role in modulating the immune response.CD47,a cell surface protein,has been identified as a crucial regulator of the TME and a potential therapeutic target for cancer therapy.However,the precise functions and implications of CD47 in the TME during immunotherapy for cancer patients remain incompletely understood.This comprehensive review aims to provide an overview of CD47’s multifaced role in TME regulation and immune evasion,elucidating its impact on various types of immunotherapy outcomes,including checkpoint inhibitors and CAR T-cell therapy.Notably,CD47-targeted therapies offer a promising avenue for improving cancer treatment outcomes,especially when combined with other immunotherapeutic approaches.The review also discusses current and potential CD47-targeted therapies being explored for cancer treatment and delves into the associated challenges and opportunities inherent in targeting CD47.Despite the demonstrated effectiveness of CD47-targeted therapies,there are potential problems,including unintended effects on healthy cells,hematological toxicities,and the development if resistance.Consequently,further research efforts are warranted to fully understand the underlying mechanisms of resistance and to optimize CD47-targeted therapies through innovative combination approaches,ultimately improving cancer treatment outcomes.Overall,this comprehensive review highlights the significance of CD47 as a promising target for cancer immunotherapy and provides valuable insight into the challenges and opportunities in developing effective CD47-targeted therapies for cancer treatment.

关键词： CD47 Cancer immunotherapy CD47-targeted therapies Tumor microenvironment Macrophage Cancer cell Immune evasion Checkpoint inhibitors CAR T-cell therapy Cancer treatment outcomes

HT700高温合金旋转摩擦焊接接头组织和力学性能的研究

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热力发电 2024年第5期53卷 10-18页

作者：陈文学鲁金涛黄锦阳徐雅欣党莹樱李文亚西安热工研究院有限公司高效灵活煤电及碳捕集利用封存全国重点实验室陕西西安710054 西北工业大学材料学院陕西西安710072

用旋转摩擦焊接(RFW)方法对HT700高温合金进行焊接,并对焊接试样进行焊后热处理(PWTH)。通过光学显微镜、扫描电子显微镜、透射电子显微镜、显微硬度计、室温和750℃拉伸实验,对接头微观组织和力学性能进行系统研究。结果表明:焊态接头... 详细信息

用旋转摩擦焊接(RFW)方法对HT700高温合金进行焊接,并对焊接试样进行焊后热处理(PWTH)。通过光学显微镜、扫描电子显微镜、透射电子显微镜、显微硬度计、室温和750℃拉伸实验,对接头微观组织和力学性能进行系统研究。结果表明:焊态接头分为焊缝中心区(WCZ)、热力影响区(TMAZ)和热影响区(HAZ)3个典型区域,其中显微组织从等轴细晶粒(WCZ)、变形粗晶粒(TMAZ)逐渐转变为与母材类似的等轴晶粒(HAZ);RFW过程中WCZ发生了动态再结晶及强化相的溶解,其中γ′强化相的溶解程度大于M23C6或MC碳化物;从焊接界面到母材,焊态接头的晶粒尺寸、形状和强化相分布等微观结构逐渐发生变化,γ′相的溶解导致焊态接头力学性能较差,且在750℃时,晶界滑动使其力学性能进一步下降;焊后热处理后,晶粒生长、强化相的再析出和焊后微观组织均匀化使得接头室温和高温拉伸强度显著提高,且接头高温延展性得到一定程度的改善。本研究可为HT700高温合金的高质量焊接提供新思路。

关键词： HT700高温合金摩擦焊接热处理微观组织力学性能