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Parachute dynamics and perturbation analysis of precision airdrop system

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Chinese Journal of Aeronautics 2016年第3期29卷 596-607页

作者： Gao Xinglong zhang qingbin Tang Qiangang College of Aerospace Science and Engineering National University of Defense TechnologyChangsha 410073China

To analyze the parachute dynamics and stability characteristics of precision airdrop system, the fluid-structure interaction （FSI） dynamics coupling with the flight trajectory of a para- chute payload system is comprehensively predicted by numerical methods. The inflation behavior of a disk-gap-band parachute is specifically investigated using the arbitrary Lagrangian Euler （ALE） penalty coupling method. With the available aerodynamic data obtained from the FSI sim- ulation, a nine-degree-of-freedom （9DOF） dynamic model of a parachute-payload system is built and solved to simulate the descent trajectory of the multi-body dynamic system. Finally, a linear five-degree-of-freedom （5DOF） dynamic model is developed, the perturbation characteristics and the motion laws of the parachute and payload under a wind gust are analyzed by the linearization method and verified by a comparison with flight test data. The results of airdrop test demonstrate that our method can be further applied to the guidance and control of precision airdrop systems.

关键词： Airdrop system Flight dynamics Fluid structure interaction Parachute Perturbation analysis

Modeling of contact temperatures and their influence on the tribological performance of PEEK and PTFE in a dual-pin-ondisk tribometer

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Friction 2023年第4期11卷 546-566页

作者： Zhibin LIN Ting QU Ke zhang qingbin zhang Shengdao WANG Guibin WANG Bingzhao GAO Guowei FAN State Key Laboratory of Automotive Simulation and Control Jilin UniversityChangchun 130025China Key Laboratory of High Performance Plastics Ministry of EducationJilin UniversityChangchun 130012China Clean Energy Automotive Engineering Center Tongji UniversityShanghai 201804China College of Instrumentation and Electrical Engineering Jilin UniversityChangchun 130061China

The direct blending of polyether ether ketone(PEEK)with a solid lubricant such as polytetrafluoroethylene(PTFE)improves its tribological performance,but compromises its outstanding mechanical properties and *** these negative effects might be circumvented via the hybrid wear method,the influence of the contact temperature between multiple sliding components acting together is not fully ***,an analytical temperature model considering the influence of both micro-and macro-thermal behavior is extended to predict the contact temperature of a dual-pin-on-disk hybrid wear *** interactions between several heat sources are investigated and experimentally *** analytical results show that the nominal temperature rise of the shared wear track is determined by the combined effect of the heat generated by both pin components,while the rise in flash temperature at the region in contact with each pin component is dependent upon its individual characteristics and working ***,while different temperature peaks can coexist in the shared wear track,the maximum value dominates the performance of the *** the experimentally investigated PEEK–PTFE–steel hybrid wear system,the formation of tribofilms is blocked,and the hybrid wear system fails,when the peak temperature exceeds the glass transition temperature of both pins due to an increase in applied load.

关键词： contact temperature frictional heating dual-pin-on-disk hybrid wear

Chondroinductive/chondroconductive peptides and their-functionalized biomaterials for cartilage tissue engineering

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Bioactive Materials 2022年第3期7卷 221-238页

作者： Mingjing Zhu Wenchao Zhong Wei Cao qingbin zhang Gang Wu Department of Temporomandibular Joint Affiliated Stomatology Hospital of Guangzhou Medical UniversityGuangzhou Key Laboratory of Basic and Applied Research of Oral Regenerative MedicineGuangzhouGuangdong510182China Department of Oral and Maxillofacial Surgery/Pathology Amsterdam UMC and Academic Center for Dentistry Amsterdam(ACTA)Vrije Universiteit Amsterdam(VU)Amsterdam Movement Science(AMS)Amsterdamthe Netherlands Department of Oral Cell Biology Academic Centre for Dentistry Amsterdam(ACTA)University of Amsterdam and Vrije Universiteit AmsterdamAmsterdam Movement SciencesAmsterdamthe Netherlands

The repair of articular cartilage defects is still challenging in the fields of orthopedics and maxillofacial surgery due to the avascular structure of articular cartilage and the limited regenerative capacity of mature *** provide viable treatment options,tremendous efforts have been made to develop various chondrogenically-functionalized biomaterials for cartilage tissue *** that are derived from and mimic the functions of chondroconductive cartilage extracellular matrix and chondroinductive growth factors,represent a unique group of bioactive agents for chondrogenic *** they can be chemically synthesized,peptides bear better reproducibility,more stable efficacy,higher modifiability and yielding efficiency in comparison with naturally derived biomaterials and recombinant growth *** this review,we summarize the current knowledge in the designs of the chondroinductive/chondroconductive peptides,the underlying molecular mechanisms and their-functionalized biomaterials for cartilage tissue *** also systematically compare their in-vitro and in-vivo efficacies in inducing *** vision is to stimulate the development of novel peptides and their-functionalized biomaterials for cartilage tissue engineering.

关键词： Chondroinductive Chondroconductive Peptide Biomaterial Cartilage tissue engineering

All-optical attosecond time domain interferometry

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National Science Review 2021年第10期8卷 15-22页

作者： Zhen Yang Wei Cao Yunlong Mo Huiyao Xu Kang Mi Pengfei Lan qingbin zhang Peixiang Lu Wuhan National Laboratory for Optoelectronics and School of Physics Huazhong University of Science and Technology Hubei Key Laboratory of Optical Information and Pattern Recognition Wuhan Institute of Technology CAS Center for Excellence in Ultra-intense Laser Science

Interferometry, a key technique in modern precision measurements, has been used for length measurement in engineering metrology and astronomy. An analogous time-domain interferometric technique would represent a significant complement to spatial domain applications and require the manipulation of interference on extreme time and energy scales. Here, we report an all-optical interferometer using laser-driven high order harmonics as attosecond temporal slits. By controlling the phase of the temporal slits with an external field, a time domain interferometer that preserves both attosecond temporal resolution and hundreds of me V energy resolution is implemented. We apply this exceptional temporal resolution to reconstruct the waveform of an arbitrarily polarized optical pulse, and utilize the provided energy resolution to interrogate the abnormal character of the transition dipole near the Cooper minimum in argon. This novel attosecond interferometry paves the way for high precision measurements in the time-energy domain using all-optical approaches.

关键词： interferometry attosecond all-optical precision measurement

An investigation on tether-tugging de-orbit of defunct geostationary satellites

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Science China(Technological Sciences) 2012年第7期55卷 2019-2027页

作者： LIU HaiTao YANG LePing zhang qingbin ZHU YanWei College of Aerospace and Materials Engineering National University of Defense TechnologyChangsha 410073China

In recent years,defunct satellites mitigation in the geostationary orbit(GEO) has become a hot issue in the space *** to transfer defunct geostationary satellites to the graveyard orbit safely,economically and efficiently presents new challenges to spacecraft dynamics and *** paper conducts an in-depth investigation on tether-tugging de-orbit issues of defunct geostationary ***,a four-phase tether-tugging de-orbit scheme including acceleration,equilibrium,rotation and return is *** scheme takes into consideration how to avoid the risks of tether ripping,tug-target collision,and tether twist,and how to achieve the mission objective of fuel ***,the dynamics model of the tether combination system is established based on Lagrange equation,and the four phases of tether-tugging de-orbit scheme are simulated *** results indicate that the scheme is theoretically feasible and satisfies the design objectives of safety,economy and efficiency,providing a technical approach for engineering application.

关键词： geostationary orbit defunct satellites graveyard orbit tether-tugging de-orbit

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Probing time delay of strong-field resonant above-threshold ionization

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Chinese Physics B 2021年第1期30卷 215-220页

作者： Shengliang Xu qingbin zhang Cheng Ran Xiang Huang Wei Cao Peixiang Lu School of Physics and Wuhan National Laboratory for Optoelectronics Huazhong University of Science and TechnologyWuhan 430074China Hubei Key Laboratory of Optical Information and Pattern Recognition Wuhan Institute of TechnologyWuhan 430205China

The high-resolution three-dimensional photoelectron momentum distributions via above-threshold ionization(ATI)of Xe atoms are measured in an intense near circularly polarized laser field using velocity map imaging and tomography reconstruction. Compared to the linearly polarized laser field, the employed near circularly polarized laser field imposes a more strict selection rule for the transition via resonant excitation, and therefore we can selectively enhance the resonant ATI through certain atomic Rydberg states. Our results show the self-reference ionization delay, which is determined from the difference between the measured streaking angles for nonadiabatic ATI via the 4 f and 5 f Rydberg states, is 45.6 as. Our method provides an accessible route to highlight the role of resonant transition between selected states, which will pave the way for fully understanding the ionization dynamics toward manipulating electron motion as well as reaction in an ultrafast time scale.

关键词： above threshold ionization resonant ionization delay transition selection rule

Full experimental determination of tunneling time with attosecond-scale streaking method

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Light(Science & Applications) 2022年第8期11卷 1903-1908页

作者： Miao Yu Kun Liu Min Li Jiaqing Yan Chuanpeng Cao Jia Tan Jintai Liang Keyu Guo Wei Cao Pengfei Lan qingbin zhang Yueming Zhou Peixiang Lu Wuhan National Laboratory for Optoelectronics and School of Physics Huazhong University of Science and Technology430074WuhanChina Jiangsu Key Laboratory of Micro and Nano Heat Fluid Flow Technology and Energy Application School of Physical Science and TechnologySuzhou University of Science and Technology215009SuzhouChina Optics Valley Laboratory 430074HubeiChina

Tunneling is one of the most fundamental and ubiquitous processes in the quantum *** question of how long a particle takes to tunnel through a potential barrier has sparked a long-standing debate since the early days of quantum ***,we propose and demonstrate a novel scheme to accurately determine the tunneling time of an *** this scheme,a weak laser field is used to streak the tunneling current produced by a strong elliptically polarized laser field in an attoclock configuration,allowing us to retrieve the tunneling ionization time relative to the field maximum with a precision of a few *** overcomes the difficulties in previous attoclock measurements wherein the Coulomb effect on the photoelectron momentum distribution has to be removed with theoretical models and it requires accurate information of the driving laser *** demonstrate that the tunneling time of an electron from an atom is close to zero within our experimental *** study represents a straightforward approach toward attosecond time-resolved imaging of electron motion in atoms and molecules.

关键词： tunneling quantum scheme

Dicalcium silicate-induced mitochondrial dysfunction and autophagy-mediated macrophagic inflammation promotes osteogenic differentiation of BMSCs

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Regenerative Biomaterials 2022年第1期9卷 93-106页

作者： Qianting Luo Xingyang Li Wenchao Zhong Wei Cao Mingjing Zhu Antong Wu Wanyi Chen Zhitong Ye Qiao Han Duraipandy Natarajan Janak L.Pathak qingbin zhang Department of Temporomandibular Joint Affiliated Stomatology Hospital of Guangzhou Medical UniversityGuangdong Engineering Research Center of Oral Restoration and ReconstructionGuangzhou Key Laboratory of Basic and Applied Research of Oral Regenerative MedicineGuangzhou 510182China Jiangmen Central Hospital Affiliated Jiangmen Hospital of Sun Yat-sen UniversityJiangmen 529030China Department of Oral Cell Biology Academic Centre of Dentistry Amsterdam(ACTA)Vrije Universiteit Amsterdam and University of AmsterdamAmsterdam 1081LAThe Netherlands Affiliated Stomatology Hospital of Guangzhou Medical University Guangdong Engineering Research Center of Oral Restoration and ReconstructionGuangzhou Key Laboratory of Basic and Applied Research of Oral Regenerative MedicineGuangzhou 510182China

Dicalcium silicate(Ca_(2)SiO_(4),C_(2)S)has osteogenic potential but induces macrophagic *** function plays a vital role in macrophage polarization and macrophagic *** mitochondrial function of C_(2)S-treated macrophages is still *** study hypothesized:(i)the C_(2)S modulates mitochondrial function and autophagy in macrophages to regulate macro-phagic inflammation,and(ii)C_(2)S-induced macrophagic inflammation regulates *** used RAW264.7 cells as a model of *** C_(2)S(75–150μg/ml)extract was used to analyze the macrophagic mitochondrial function and macrophagemediated effect on osteogenic differentiation of mouse bone marrow-derived mesenchymal stem cells(BMSCs).The results showed that C_(2)S extract(150μg/ml)induced TNF-α,IL-1βand IL-6 production in macrophages.C_(2)S extract(150μg/ml)enhanced reactive oxygen species level and intracellular calcium level but reduced mitochondrial membrane potential and ATP *** images showed reduced mitochondrial abundance and altered the mitochondrial morphology in C_(2)S(150μg/ml)-treated *** level expression of PINK1,Parkin,Beclin1 and LC3 was upregulated but TOMM20 was *** sequencing and KEGG analysis showed that C_(2)S-induced differentially expressed mRNAs in macrophages were mainly distributed in the essential signaling pathways involved in mitochondrial function and *** conditioned medium from C_(2)S-treated macrophage robustly promoted osteogenic differentiation in *** conclusion,our results indicate mitochondrial dysfunction and autophagy as the possible mechanism of C_(2)S-induced macrophagic *** promotion of osteogenic differentiation of BMSCs by the C_(2)S-induced macrophagic inflammation suggests the potential application of C_(2)S in developing immunomodulatory bone grafts.

关键词： dicalcium silicate macrophagic inflammation mitochondrial function autophagy osteogenesis

260 fs,403 W coherently combined fiber laser with precise high‑order dispersion management

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Frontiers of Optoelectronics 2024年第1期17卷 21-27页

作者： Shuangxi Peng Zhihao Wang Feilong Hu Zhengyan Li qingbin zhang Peixiang Lu Wuhan National Laboratory for Optoelectronics and School of Physics Huazhong University of Science and TechnologyWuhan 430074China School of Optical and Electronic Information Huazhong University of Science and TechnologyWuhan 430074China Optics Valley Laboratory Wuhan 430074China

An ultrafast fiber laser system comprising two coherently combined amplifier channels is *** this system,each channel incorporates a rod-type fiber power amplifier,with individual operations reaching approximately 233 *** active-locking of these coherently combined channels,followed by compression using gratings,yields an output with a pulse energy of 504μJ and an average power of 403 *** stability is maintained,with a 0.3%root mean square(RMS)deviation and a beam quality factor M^(2)<***,precise dispersion management of the front-end seed light effectively compensates for the accumulated high-order dispersion in subsequent amplification *** strategic approach results in a significant reduction in the final output pulse duration for the coherently combined laser beam,reducing it from 488 to 260 fs after the gratings compressor,while concurrently enhancing the energy of the primary peak from 65%to 92%.

关键词： Fiber lasers amplifier Power scaling Coherent beam combination Dispersion compensation