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High-speed penetration of ogive-nose projectiles into thick concrete targets:Tests and a projectile nose evolution model

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Defence Technology（防务技术） 2024年第2期32卷 553-571页

作者： Xu Li Yan Liu Junbo Yan Zhenqing Shi hongfu wang Yingliang Xu Fenglei Huang State Key Laboratory of Explosion Science and Technology Beijing Institute of TechnologyBeijing100081China Beijing Institute of Technology Chongqing Innovation Center Chongqing401120China China Research and Development Academy of Machinery Equipment Beijing100089China

The majority of the projectiles used in the hypersonic penetration study are solid flat-nosed cylindrical projectiles with a diameter of less than 20 mm.This study aims to fill the gap in the experimental and analytical study of the evolution of the nose shape of larger hollow projectiles under hypersonic penetration.In the hypersonic penetration test,eight ogive-nose AerMet100 steel projectiles with a diameter of 40 mm were launched to hit concrete targets with impact velocities that ranged from 1351 to 1877 m/s.Severe erosion of the projectiles was observed during high-speed penetration of heterogeneous targets,and apparent localized mushrooming occurred in the front nose of recovered projectiles.By examining the damage to projectiles,a linear relationship was found between the relative length reduction rate and the initial kinetic energy of projectiles in different penetration tests.Furthermore,microscopic analysis revealed the forming mechanism of the localized mushrooming phenomenon for eroding penetration,i.e.,material spall erosion abrasion mechanism,material flow and redistribution abrasion mechanism and localized radial upsetting deformation mechanism.Finally,a model of highspeed penetration that included erosion was established on the basis of a model of the evolution of the projectile nose that considers radial upsetting;the model was validated by test data from the literature and the present study.Depending upon the impact velocity,v0,the projectile nose may behave as undistorted,radially distorted or hemispherical.Due to the effects of abrasion of the projectile and enhancement of radial upsetting on the duration and amplitude of the secondary rising segment in the pulse shape of projectile deceleration,the predicted DOP had an upper limit.

关键词： High-speed penetration Concrete target Erosion Projectile nose evolution model

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Research on the quasi-isentropic driving model of aluminized explosives in the detonation wave propagation direction

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Defence Technology（防务技术） 2024年第2期32卷 596-618页

作者： hongfu wang Yan Liu Fan Bai Chao He Yingliang Xu Qiang Zhou Chuan Xiao Fenglei Huang State Key Laboratory of Explosion Science and Technology Beijing Institute of TechnologyBeijing100081China China Research and Development Academy of Machinery Equipment Beijing100089China Beijing Institute of Technology Chongqing Innovation Center Chongqing401120China

Taking CL-20(Hexanitrohexaazaisowurtzitane)-based aluminized explosives with high gurney energy as the research object, this research experimentally investigates the work capability of different aluminized explosive formulations when driving metal flyer plates in the denotation wave propagation direction.The research results showed that the formulations with 43 μm aluminum(Al) powder particles(The particle sizes of Al powder were in the range of 2~43 μm) exhibited the optimal performance in driving flyer plates along the denotation wave propagation direction. Compared to the formulations with Al powder 13 μm, the formulations with Al powder 2 μm delivered better performance in accelerating metal flyer plates in the early stage, which, however, turned to be poor in the later stage. The CL-20-based explosives containing 25% Al far under-performed those containing 15% Al. Based on the proposed quasi-isentropic hypothesis, relevant isentropy theories, and the functional relationship between detonation parameters and entropy as well as Al reaction degree, the characteristic lines of aluminized explosives in accelerating flyer plates were theoretically studied, a quasi-isentropic theoretical model for the aluminized explosive driving the flyer plate was built and the calculation methods for the variations of flyer plate velocity, Al reaction degree, and detonation product parameters with time and axial positions were developed. The theoretical model built is verified by the experimental results of the CL-20-based aluminized explosive driving flyer plate. It was found that the model built could accurately calculate the variations of flyer plate velocity and Al reaction degree over time. In addition, how physical parameters including detonation product pressure and temperature varied with time and axial positions was identified. The action time of the positive pressure after the detonation of aluminized explosives was found prolonged and the downtrend of the temperature was slowed down and even reversed to a slight rise

关键词： Aluminized explosive Flyer plate experiment Quasi-isentropic theoretical model Al reaction Driving characteristics

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Preparation of Laser Cladding Coating Undercooling Cu-based Alloy and Co on Non-equilibrium Solidification Structure

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Journal of Wuhan University of Technology(Materials Science) 2024年第2期39卷 463-472页

作者：田徐铭 CAO Shichao HOU Kai HOU Xiaopeng wang hongfu 张煜 Department of Outpatient Xinzhou People’s HospitalXinzhou 034099China School of Mechanical Engineering North University of ChinaTaiyuan 030051China Department of Neurosurgery Xinzhou People’s HospitalXinzhou 034099China Department of Orthopedics Xinzhou People’s HospitalXinzhou 034099China

The effect of the gradient content of Co element on the solidification process of Cu-based alloy under deep under cooling conditions was explored.The non-equilibrium solidification structure of the under cooled alloy samples were analyzed.It is found that the rapidly solidified alloy has undergone twice grain refinement during the undercooling process.Characterization and significance of the maximum undercooling refinement structure of Cu60Ni35Co5 at T=253 K were analyzed.High-density defects were observed,such as dislocations,stacking faults networks,and twinning structures.The standard FCC diffraction pattern represents that it is still a single-phase structure.Based on the metallographic diagram,EBSD and TEM data analysis,it is illustrated that the occurrence of grain refinement under high undercooling is due to stress induced recrystallization.In addition,the laser cladding technology is used to coat Co-based alloy(Stellite12) coating on 304 stainless steel substrate;the microstructure of the coating cross-section was analyzed.It was found that the microstructure of the cross-section is presented as columnar crystals,planar crystals,and disordered growth direction,so that the coating has better hardness and wear resistance.By electrochemical corrosion of the substrate and coating,it can be seen that the Co and Cr elements present in the coating are more likely to form a dense passivation film,which improved the corrosion resistance of the coating.

关键词： non-equilibrium solidification structure undercooling recrystallization laser cladding coating

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Bactericidal bissulfone B7 targets bacterial pyruvate kinase to impair bacterial biology and pathogenicity in plants

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Science China(Life Sciences) 2024年第2期67卷 391-402页

作者： Awei Zhang Haizhen Zhang Ronghua wang hongfu He Baoan Song Runjiang Song National Key Laboratory of Green Pesticide Key Laboratory of Green Pesticide and Agricultural BioengineeringMinistry of EducationCenter for R&D of Fine Chemicals of Guizhou UniversityGuiyang 550025China

The prevention and control of rice bacterial leaf blight(BLB)disease has not yet been achieved due to the lack of effective agrochemicals and available targets.Herein,we develop a series of novel bissulfones and a novel target with a unique mechanism to address this challenge.The developed bissulfones can control Xanthomonas oryzae pv.oryzae(Xoo),and 2-(bis(methylsulfonyl)methylene)-N-(4-chlorophenyl)hydrazine-1-carboxamide(B_(7))is more effective than the commercial drugs thiodiazole copper(TC)and bismerthiazol(BT).Pyruvate kinase(PYK)in Xoo has been identified for the first time as the target protein of our bissulfone B_(7).PYK modulates bacterial virulence via a CRP-like protein(Clp)/two-component system regulatory protein(reg R)axis.The elucidation of this pathway facilitates the use of B_(7)to reduce PYK expression at the transcriptional level,block PYK activity at the protein level,and impair the interaction within the PYK-Clp-reg R complex via competitive inhibition,thereby attenuating bacterial biology and pathogenicity.This study offers insights into the molecular and mechanistic aspects underlying anti-Xoo strategies that target PYK.We believe that these valuable discoveries will be used for bacterial disease control in the future.

关键词： 2-bissulfone-N-phenylhydrazine-1-carboxamide derivatives Xoo antibacterial activities pyruvate kinase regulatory mechanism

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Coherent link between a Ti:sapphire comb and a 1.5μm laser via nonlinear interaction in photonic crystal fiber

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Photonics Research 2024年第2期12卷 350-355页

作者： YUAN YAO HAOSEN SHI GUANG YANG BO LI CONGYU wang hongfu YU LONGSHENG MA YANYI JIANG State Key Laboratory of Precision Spectroscopy East China Normal UniversityShanghai 200062China Collaborative Innovation Center of Extreme Optics Shanxi UniversityTaiyuan 030006China

Optical clock networks have distinct advantages for the dissemination of time/frequency,geodesy,and fundamental research.To realize such a network,the telecom band and optical atomic clocks have to be coherently bridged.Since the telecom band and optical atomic clocks reside in a distinct spectral region,second-harmonic generation is usually introduced to bridge the large frequency gap.In this paper,we introduce a new method to coherently link a 1550 nm continuous wave laser with a Ti:sapphire mode-locked laser-based optical frequency comb.By coupling the 1550 nm continuous wave laser light and the Ti:sapphire comb light together into a photonic crystal fiber,nonlinear interaction takes place,and new comblike frequency components related to the 1550 nm laser frequency are generated in the visible region.Consequently,we can detect beat notes between two combs in the visible region with a signal-to-noise ratio of more than 40 dB in a resolution bandwidth of300 kHz.With this signal,we realize an optical frequency divider for converting the frequency of optical clocks in the visible region to the telecom band at 1.55μm.An out-of-loop measurement shows that the additional noise and uncertainty induced in optical frequency conversion are 5×10^(-18)at 1 s averaging time and 2.2×10^(-19),respectively,which are limited by the uncompensated light path fluctuation but fulfill precision measurement using state-of-the-art optical clocks.

关键词： fiber interaction nonlinear

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Microstructure evolution and grain refinement mechanism of rapidly solidified single-phase copper based alloys

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Journal of Materials Science & Technology 2022年第33期128卷 160-179页

作者： Xiaolong Xu Cheng Tang hongfu wang Yukang An Yuhong Zhao College of Materials Science and Engineering School of Mechanical EngineeringNorth University of ChinaTaiyuanShanxi 030051China

The Cu65Ni35,Cu60Ni40 and Cu55Ni45 alloys were undercooled by fluxing method,and the rapid solidification structure with different undercoolings were also obtained.At the same time,the interface migration process during rapid solidification was photographed by high-speed photography,and the relationship between the morphological characteristics of solidification front and undercooling was analyzed.The microstructures of the three alloys were observed by metallographic microscope,and the microstructure characteristics and evolution law were systematically studied.It was found that two grain refinement events occurred in the low undercooling range and high undercooling range,respectively.The EBSD test of grain refined microstructures showed that the microstructure in the low undercooling range has a high proportion of low-angle grain boundaries and high strength textures.However,there were a large proportion of high-angle grain boundaries and a high proportion of twin grain boundaries and more randomly oriented grains in the microstructure in the high undercooling range.The TEM test of the Cu55Ni45 alloy with the maximum undercooling of 284 K showed that there were high-density dislocation networks and stacking faults in the grains.Finally,the evolution relationship between microstructure hardness and undercooling was systematically studied.It was found that the microhardness of the three alloys decreased sharply near the critical undercooling.Combined with EBSD,TEM and microhardness analysis,it was confirmed that the grain refinement under low undercooling was caused by dendrite remelting,while the grain refinement under high undercooling was caused by stress-induced recrystallization.

关键词： Rapid solidification structure Grain refinement Dendrite remelting Recrystallization

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Efficacy and safety of single microneedle radiofrequency vs. photodynamic therapy on moderate-to-severe acne vulgaris: A prospective, randomized, controlled study

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中华医学杂志(英文版) 2024年第8期137卷 2024 Jan 9页

作者： Huang Chuchu Mao Mengping Peng Yiran wang Ben Deng Yuxuan Xie hongfu Jian Dan D-53127 Bonn Germany Department of Dermatology Xiangya Hospital Central South University Changsha Hunan 410008 China Department of Dermatology and Allergy and Christine Kühne-Center for Allergy Research and Education University Hospital of Bonn

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电加热服加热区域分布对人体热舒适感的影响

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纺织学报 2024年第4期45卷 188-194页

作者：柯莹林磊郑晴王宏付江南大学设计学院江苏无锡214122 江南大学纺织科学与工程学院江苏无锡214122

为探究加热区域分布对电加热服热舒适性的影响规律,设计了3种加热区域,在环境温度为(5±0.5)℃,相对湿度为(50±5)%的条件下进行真人着装实验,记录受试者客观生理数据和主观感受并对其进行分析。实验结果表明:在加热面积一定的情况下,... 详细信息

为探究加热区域分布对电加热服热舒适性的影响规律,设计了3种加热区域,在环境温度为(5±0.5)℃,相对湿度为(50±5)%的条件下进行真人着装实验,记录受试者客观生理数据和主观感受并对其进行分析。实验结果表明:在加热面积一定的情况下,将加热片集中分布在上半身躯干位置能显著提高平均躯干温度,对平均皮肤温度的提高作用不大;相比之下,躯干加上腿部的加热区域组合能有效提高平均皮肤温度0.8℃以上,躯干、大腿和大臂的加热区域组合能将平均皮肤温度提高0.5℃;另外,将加热片分布到四肢相较于集中加热躯干对改善热感觉和热舒适的效果更好。建议当加热面积一定时,将加热片分布到躯干以及腿部位置,可使电加热服具有较好的功能性和舒适性。

关键词：电加热服加热区域皮肤温度热感觉热舒适性

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A Yb optical clock with a lattice power enhancement cavity

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Chinese Physics B 2024年第3期33卷 70-74页

作者：王春云姚远师浩森于洪浮马龙生蒋燕义 State Key Laboratory of Precision Spectroscopy East China Normal UniversityShanghai 200062China

We construct a power enhancement cavity to form an optical lattice in an ytterbium optical clock.It is demonstrated that the intra-cavity lattice power can be increased by about 45 times,and the trap depth can be as large as 1400Er when laser light with a power of only 0.6 W incident to the lattice cavity.Such high trap depths are the key to accurate evaluation of the lattice-induced light shift with an uncertainty down to~1×10-18.By probing the ytterbium atoms trapped in the power-enhanced optical lattice,we obtain a 4.3 Hz-linewidth Rabi spectrum,which is then used to feedback to the clock laser for the close loop operation of the optical lattice clock.We evaluate the density shift of the Yb optical lattice clock based on interleaving measurements,which is-0.46(62)mHz.This result is smaller compared to the density shift of our first Yb optical clock without lattice power enhancement cavity mainly due to a larger lattice diameter of 344μm.

关键词： optical atomic clock optical lattice optical cavity Stark shift

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Transformer与CNN并行引导的水下图像增强

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计算机工程与应用 2024年第4期60卷 280-288页

作者：常戬陈洪福王冰冰辽宁工程技术大学软件学院辽宁葫芦岛125105

为克服水下图像对比度低和色偏的问题,提出了基于Transformer与CNN并行引导的水下图像增强算法。利用3D位置嵌入模型为Transformer提供相对位置信息、色偏信息和特征图的全局特征,利用CNN编码器提取图像局部特征,将Transformer提取的全... 详细信息

为克服水下图像对比度低和色偏的问题,提出了基于Transformer与CNN并行引导的水下图像增强算法。利用3D位置嵌入模型为Transformer提供相对位置信息、色偏信息和特征图的全局特征,利用CNN编码器提取图像局部特征,将Transformer提取的全局特征和CNN提取的局部特征通过特征调制矩阵整合在一起,通过CNN解码器提高图像的分辨率,将解码器输出的特征图输入到特征加强网络中,由特征加强网络输出最终结果。采用现有的EUVP配对数据集进行训练,为验证该算法的优越性,选取具有不同程度色偏的水下图像进行定性比较和定量实验,结果显示,该算法增强后的水下图像峰值信噪比指标(peak signal-to-noise ratio,PSNR)和结构相似性指标(structural similarity index measure,SSIM)均高于其他对比算法,主观质量也得到显著提高,能够产生颜色丰富且清晰度较高的增强图像。

关键词：水下图像增强 Transformer 卷积神经网络(CNN) 3D位置嵌入模型特征调制矩阵

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