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Fluorine-Doped High-Performance Li_(6)PS_(5)Cl Electrolyte by Lithium Fluoride Nanoparticles for All-Solid-State Lithium-Metal Batteries

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Transactions of Tianjin University 2024年第3期30卷 250-261页

作者： Xiaorou cao shijie Xu Yuzhe {2. Xiaohu Hu Yifan Yan Yanru Wang Haoran Qian Jiakai Wang Haolong Chang Fangyi Cheng Yongan Yang institute of Molecular Plus School of Chemical Engineering and TechnologyTianjin UniversityTianjin 300072China Haihe Laboratory of Sustainable Chemical Transformations Tianjin 300192China Key Laboratory of Advanced Energy Materials Chemistry(Ministry of Education) Nankai UniversityTianjin 300071China

All-solid-state lithium-metal batteries(ASSLMBs)are widely considered as the ultimately advanced lithium batteries owing to their improved energy density and enhanced safety *** various solid electrolytes,sulfide solid electrolyte(SSE)Li_(6)PS_(5)Cl has garnered significant ***,its application is limited by its poor cyclability and low critical current density(CCD).In this study,we introduce a novel approach to enhance the performance of Li_(6)PS_(5)Cl by doping it with fluorine,using lithium fluoride nanoparticles(LiFs)as the doping *** F-doped electrolyte Li_(6)PS_(5)Cl-0.2.iF(nano)shows a doubled CCD,from 0.5 to 1.0 mA/cm^(2. without compromising the ionic conductivity;in fact,conductivity is enhanced from 2.82.to 3.30 mS/cm,contrary to the typical performance decline seen in conventionally doped Li_(6)PS_(5)Cl *** symmetric Li|SSE|Li cells,the lifetime of Li_(6)PS_(5)Cl-0.2.iF(nano)is 4 times longer than that of Li_(6)PS_(5)Cl,achieving 1500 h vs.371 h under a charging/discharging current density of 0.2.mA/cm^(2..In Li|SSE|LiNbO_(3)@NCM72. full cells,which are tested under a cycling rate of 0.1 C at 30℃,the lifetime of Li_(6)PS_(5)Cl-0.2.iF(nano)is four times that of Li_(6)PS_(5)Cl,reaching 100 cycles vs.2. ***,the doping of nano-LiF off ers a promising approach to developing high-performance Li_(6)PS_(5)Cl for ASSLMBs.

关键词： Sulfide solid electrolyte All-solid-state lithium batteries Li_(6)PS_(5)Cl Lithium fluoride F-doping

Specifications and control of spatial frequency errors of components in two-beam laser static holographic exposure for pulse compression grating fabrication

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High Power Laser Science and Engineering 2024年第1期12卷 1-12页

作者： Chen Hu Songlin Wan Guochang Jiang Haojin Gu Yibin zhang Yunxia Jin shijie Liu Chengqiang Zhao Hongchao {2. Chaoyang Wei Jianda Shao Precision Optical Manufacturing and Testing Center Shanghai Institute of Optics and Fine MechanicsChinese Academy of Sciences(CAS)ShanghaiChina Key Laboratory for High Power Laser Material of Chinese Academy of Sciences Shanghai Institute of Optics and Fine MechanicsCASShanghaiChina Center of Materials Science and Optoelectronics Engineering University of Chinese Academy of SciencesBeijingChina Hangzhou institute for Advanced Study University of Chinese Academy of SciencesHangzhouChina china-Russian Belt and Road Joint Laboratory on Laser Science ShanghaiChina

The large-aperture pulse compression grating(PCG) is a critical component in generating an ultra-high-intensity, ultra-short-pulse laser;however, the size of the PCG manufactured by transmission holographic exposure is limited to large-scale high-quality materials. The reflective method is a potential way for solving the size limitation, but there is still no successful precedent due to the lack of scientific specifications and advanced processing technology of exposure mirrors. In this paper, an analytical model is developed to clarify the specifications of components, and advanced processing technology is adopted to control the spatial frequency errors. Hereafter, we have successfully fabricated a multilayer dielectric grating of 2.0 mm × 150 mm by using an off-axis reflective exposure system with Φ300 mm. This demonstration proves that PCGs can be manufactured by using the reflection holographic exposure method and shows the potential for manufacturing the meter-level gratings used in 100 petawatt class high-power lasers.

关键词： high-power laser off-axis reflective exposure system pulse compression grating spatial frequency errors specifications

Preparation and Properties of Smart Thermal Control and Radiation Protection Materials for Multi-functional Structure of Small Spacecraft

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Journal of Materials Science & technology 2011年第10期27卷 879-884页

作者： shijie zhang {2. cao Yingqiang Luan Xinxin Ma Xiaohui Lin Xianren Kong Research Center of Satellite technology Harbin Institute of Technology Harbin 150080 China The Second System Design of the Second Research Academy of CASIC Beijing 100854 China

Considering the unique properties of small spacecraft, such as light weight, low power-consumption and high heat flux density, a new kind of lightweight boron carbide （B4C） radiation-protection coating material was proposed. New techniques for preparing LSMO thermal control coating and B4C radiation-protection coating were developed. The sample piece of multi-functional structure was manufactured by using the proposed materials, and a series of performance tests, such as thermal control and radiation-protection behaviors were evaluated. Test results show that： the emissivity of the multi-functional structure varies from 0.42.to 0.86 at 2.0 K to 353 K and the phase transition temperature is about 2.0 K. The electron radiation-protection ability of the multi-functional structure is 3.3 times better than that of Al material. The performance index of this multi-functional structure can meet the requirements for space application in on-board electronic equipment.

关键词： Coating material Phase transition temperature Temperature-dependent emissivity-variable Radiation-protection Spacecraft

Tangent-impulse transfer from elliptic orbit to an excess velocity vector

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Chinese Journal of Aeronautics 2014年第3期27卷 577-583页

作者： zhang Gang zhang Xiangyu {2. {2. Research Center of Satellite technology Harbin Institute of Technology National and Local United Engineering Research Center of Small Satellite technology

The two-body orbital transfer problem from an elliptic parking orbit to an excess veloc-ity vector with the tangent impulse is studied. The direction of the impulse is constrained to be aligned with the velocity vector, then speed changes are enough to nullify the relative velocity. First, if one tangent impulse is used, the transfer orbit is obtained by solving a single-variable function about the true anomaly of the initial orbit. For the initial circular orbit, the closed-form solution is derived. For the initial elliptic orbit, the discontinuous point is solved, then the initial true anomaly is obtained by a numerical iterative approach; moreover, an alternative method is proposed to avoid the singularity. There is only one solution for one-tangent-impulse escape trajectory. Then, based on the one-tangent-impulse solution, the minimum-energy multi-tangent-impulse escape trajectory is obtained by a numerical optimization algorithm, e.g., the genetic method. Finally, several examples are provided to validate the proposed method. The numerical results show that the minimum-energy multi-tangent-impulse escape trajectory is the same as the one-tangent-impulse trajectory.

关键词： Elliptic orbit Escape trajectory Excess velocity vector Orbital transfer Tangent impulse

Pd(111)与Pt(111)上NO氧化的第一性原理研究

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天津大学学报（自然科学与工程技术版） 2024年第6期57卷 588-594页

作者：李志军曹飞王学豹李世龙张时杰李振国先进内燃动力全国重点实验室(天津大学) 天津300072 中国北方发动机研究所天津300400 中国汽车技术研究中心有限公司天津300300

随着排放法规的日益严格,发动机的氮氧化物(NO_(x))后处理已成为当今研究的重点问题.针对目前可有效降低稀燃汽油机NO_(x)的稀燃氮氧化物捕集器中铂(Pt)和钯(Pd)两种贵金属之间的替换问题,进行了密度泛函理论(density functional theory... 详细信息

随着排放法规的日益严格,发动机的氮氧化物(NO_(x))后处理已成为当今研究的重点问题.针对目前可有效降低稀燃汽油机NO_(x)的稀燃氮氧化物捕集器中铂(Pt)和钯(Pd)两种贵金属之间的替换问题,进行了密度泛函理论(density functional theory,DFT)计算研究.首先,对一氧化氮(NO)、氧气(O_(2.)、二氧化氮(NO_(2.)在两种催化剂(111)表面的吸附进行了研究,之后,在两催化剂表面对比研究了氧化过程中涉及的O_(2.解离与NO氧化两反应过程,揭示了NO在Pd与Pt催化剂上的氧化机理.结果显示:3种物质在催化剂表面的吸附强度为NO>O_(2.>NO_(2..氧覆盖度将会改变氮氧化物的最佳吸附构型,随着表面氧原子的增加NO会由三重空位式吸附转变为顶点吸附,NO_(2.会由μ-N,O-亚硝基吸附转变为硝基吸附.在O_(2.解离过程中Pt的催化能力优于Pd,但是两者对NO氧化的催化能力接近.在Pd和Pt表面反应限速步骤都是O_(2.的解离,Pd对O_(2.较弱的解离能力导致了其NO的转化效率低于Pt.氧覆盖度对氧化过程存在影响,通过电子结构分析发现,氧覆盖度的提升使催化剂与吸附物质之间的吸附能下降,这导致了反应由吸热变为放热,使催化可以自发进行.反应生成的NO_(2.需要1.00 eV以上的能量完成脱附,这在原子层面解释了NO_(2.对NO氧化反应的抑制作用.

关键词：稀燃氮氧化物捕集器第一性原理铂族催化剂一氧化氮氧化

Adaptive dynamic programming-based fault-tolerant attitude control for flexible spacecraft with limited wireless resources

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Science china(Information Sciences) 2023年第10期66卷 213-228页

作者： Ming LIU Qiuhong LIU Lixian zhang Guangren DUAN xibin {2. School of Astronautics Harbin Institute of Technology Beijing institute of Control Engineering

This paper investigates the attitude control for flexible spacecraft subject to actuator faults and limited onboard communication resources. The control torque quantization scheme is considered between the controller and actuator to reduce the communication burden on the spacecraft. An integral sliding mode control method is designed to stabilize the closed-loop attitude control system and ensure the near-optimal performance of the sliding motion. First, an iterative learning observer scheme is employed to reconstruct the actuator faults and the unknown nonlinear flexible dynamics. Second, an integral sliding surface is combined with the backstepping control method to resolve the time-varying characterization of the closed system. Third, a combination of the adaptive dynamic programming technique and the adaptive single critic neural network approximation is employed to examine the optimal control policy. Finally, the efficacy of the proposed spacecraft attitude control method is demonstrated via a simulation.

关键词： flexible spacecraft fault-tolerant attitude control signal quantization adaptive dynamic programming neural network learning

Hierarchical path planning for multi-arm spacecraft with general translational and rotational locomotion mode

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Science china(Technological Sciences) 2023年第4期66卷 1180-1191页

作者： YUE ChengFei LIN Tao zhang Xiao CHEN XueQin cao {2. institute of Space Science and Applied technology Harbin Institute of Technology ShenzhenShenzhen 518055China Research Center of the Satellite technology Harbin Institute of TechnologyHarbin 150001China

On-orbit construction and maintenance technology will play a significant role in future space *** dexterous multifunctional spacecraft equipped with multi-arm,for instance,Spider Fab Bot,has attracted a great deal of focus due to its versatility in completing these *** such engineering practice,point-to-point moving in a complex environment is the fundamental *** paper investigates the three-dimensional point-to-point path planning problem,and a hierarchical path planning architecture is developed to give the trajectory of the multi-arm spacecraft effectively and *** the proposed 3-level architecture,the high-level planner generates the global constrained centric trajectory of the spacecraft with a rigid envelop assumption;the middle-level planner contributes the action sequence,a combination of the newly developed general translational and rotational locomotion mode,to cope with the relative position and attitude of the arms about the centroid of the spacecraft;the low-level planner maps the position/attitude of the end-effector of each arm from the operational space to the joint space ***,the simulation experiment is carried out,and the results verify the effectiveness of the proposed three-layer architecture path planning strategy.

关键词： multi-arm spacecraft path planning hierarchical architecture locomotion mode translational locomotion rotational locomotion

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基于光束扫描的光场匀化技术

光学学报 2024年第16期44卷 20-29页

作者：张海冬赵成强张益彬曹红超晋云霞刘世杰邵建达上海大学微电子学院上海200444 中国科学院上海光学精密机械研究所薄膜光学实验室上海201800 中国科学院上海光学精密机械研究所强激光材料重点实验室上海201800

提出一种新型的光束扫描匀光方法。扫描干涉光刻后基板处的整体光场强度可以实现均匀分布,进而光栅基板处的曝光剂量就可以实现宏观上的均匀分布。对扫描匀光方法的扫描参数进行数值分析,并开展相关实验。扫描匀光的实验结果表明,当步... 详细信息

提出一种新型的光束扫描匀光方法。扫描干涉光刻后基板处的整体光场强度可以实现均匀分布,进而光栅基板处的曝光剂量就可以实现宏观上的均匀分布。对扫描匀光方法的扫描参数进行数值分析,并开展相关实验。扫描匀光的实验结果表明,当步进距离与光斑半径之比小于等于1.2.,经过光束扫描叠加后,基板处的光场均匀性优于99.00%,相较传统高斯截光的方式,均匀性至少提高5%;引入参考光进行条纹漂移锁定控制后,在?2.0 mm的扫描过程中,光束的相位变化小于±0.015个干涉条纹周期,实现了光束扫描过程中条纹“静止”在基板位置处的效果。

关键词：光栅全息光栅曝光系统光束扫描光场均匀性条纹漂移锁定

Fault diagnosis of control moment gyroscope based on a new CNN scheme using attention-enhanced convolutional block

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Science china(Technological Sciences) 2022年第11期65卷 2605-2616页

作者： ZHAO HaoTian LIU Ming SUN YiYong CHEN zhang DUAN GuangRen cao {2. Research Center of Satellite technology School of AstronauticsHarbin Institute of TechnologyHarbin 150001China School of Aerospace Engineering Beijing Institute of TechnologyBeijing 100081China Department of Automation TsinghuaUniversityBeijing 100084China Control Theory and Guidance technology School of AstronauticsHarbin Institute of TechnologyHarbin150001China

Control moment gyroscope(CMG)is a typical attitude control system component for satellites and mobile robots,and the online fault diagnosis of CMG is crucial because it determines the stability and accuracy of the attitude control *** paper develops a data-driven CMG fault diagnosis scheme based on a new CNN *** this design,seven types of fault signals are converted into spectrum datasets through short-time Fourier transformation(STFT),and a new CNN network scheme called AECB-CNN is proposed based on attention-enhanced convolutional blocks(AECB).AECB-CNN can achieve high training accuracy for the CMG fault diagnosis datasets under different sliding window ***,simulation results indicate that the proposed fault diagnosis method can achieve an accuracy of nearly 95%in 1.2. s and 100%in 2.56 s,respectively.

关键词： fault diagnosis control moment gyroscope CNN scheme attention-enhanced convolutional block