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Science China Technological Sciences 2025年

作者： Junyu HU Yourui TAO Shanhu LI xu HAN College of Mechanical and Vehicle Engineering Hunan University State Key Laboratory of Reliability and Intelligence of Electrical Equipment Hebei University of Technology

To enhance the tip positioning accuracy and robustness against disturbances of linear colocated motion systems, a novel composite feedforward (COMFF) control with Bi-Loop iterative feedforward tuning (IFFT) is proposed. The tip positioning error consists of the coupled tip residual vibration and linear motor tracking error. Given the influence of nonlinear friction and load flexibility, the topology of COMFF is designed as decoupled structures so that COMFF can suppress the tip residual vibration and compensate for the linear motor tracking error compatibly. Furthermore, Bi-Loop IFFT is built to improve the robustness of COMFF in high-precision motor tracking performance. In the state space of the linear motor tracking error based on the projection theorem, two loops are performed in parallel along the iteration direction. One is the P-type iteration loop that drives linear motor tracking errors to converge to the zero state. The other is the observation loop constructed by the recursive least square with forgetting factors to accelerate the P-type iteration loop. Driven by the P-type iteration loop with the aid of the observation loop, the proposed COMFF is integrated with fast convergence and high robustness when confronted with model disturbances. The effectiveness of the proposed COMFF combined with Bi-Loop IFFT is validated by experiments.

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Effects of mesoscale gravity waves on sporadic E simulated by a one-dimensional dynamic model

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Earth and Planetary Physics 2025年第1期9卷 1-9页

作者： xu Zhou ZeZhong Li XinAn Yue LiBo Liu Key Laboratory of Earth and Planetary Physics/Heilongjiang Mohe National Geophysical Observatory/Beijing National Observatory of Space Environment Institute of Geology and GeophysicsChinese Academy of Sciences(CAS)Beijing 100029China College of Earth and Planetary Sciences University of Chinese Academy of SciencesBeijing 100049China CAS Center for Excellence in Comparative Planetology/CAS Key Laboratory of Geospace Environment/Mengcheng National Geophysical Observatory University of Science and Technology of ChinaHefei 230026China

In addition to being driven by tidal winds,the sporadic E(Es)layers are modulated by gravity waves(GWs),although the effects are not yet comprehensively *** this article,we discuss the effects of mesoscale GWs on the Es layers determined by using a newly developed model,MISE-1D(one-dimensional Model of Ionospheric Sporadic E),with low numerical dissipation and high *** by the wind fields resolved by the high-resolution version of the Whole Atmosphere Community Climate Model with thermosphere and ionosphere extension(WACCM-X),the MISE-1D simulation revealed that GWs significantly influence the evolution of the Es layer above 100 km but have a very limited effect at lower *** effects of GWs are diverse and complex,generally including the generation of fluctuating wavelike structures on the Es layer with frequencies similar to those of the *** mesoscale GWs can also cause increases in the density of Es layers,or they can disperse or diffuse the Es layers and increase their *** addition,the presence of GWs is a key factor in sustaining the Es layers in some cases.

关键词： sporadic E ion tidal layer gravity waves numerical simulation

Advances in the Development of Gradient Scaffolds Made of Nano‑Micromaterials for Musculoskeletal Tissue Regeneration

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Nano-Micro Letters 2025年第3期17卷 455-500页

作者： Lei Fang Xiaoqi Lin Ruian xu Lu Liu Yu Zhang Feng Tian Jiao Jiao Li Jiajia xue Beijing Laboratory of Biomedical Materials Beijing University of Chemical TechnologyBeijing 100029People’s Republic of China State Key Laboratory of Organic‑Inorganic Composites Beijing University of Chemical TechnologyBeijing 100029People’s Republic of China School of Biomedical Engineering Faculty of Engineering and ITUniversity of Technology SydneySydneyNSW 2007Australia

The intricate hierarchical structure of musculoskeletal tissues,including bone and interface tissues,necessitates the use of complex scaffold designs and material structures to serve as tissue-engineered *** has led to growing interest in the development of gradient bone scaffolds with hierarchical structures mimicking the extracellular matrix of native tissues to achieve improved therapeutic *** on the anatomical characteristics of bone and interfacial tissues,this review provides a summary of current strategies used to design and fabricate biomimetic gradient scaffolds for repairing musculoskeletal tissues,specifically focusing on methods used to construct compositional and structural gradients within the *** latest applications of gradient scaffolds for the regeneration of bone,osteochondral,and tendon-to-bone interfaces are ***,the current progress of testing gradient scaffolds in physiologically relevant animal models of skeletal repair is discussed,as well as the challenges and prospects of moving these scaffolds into clinical application for treating musculoskeletal injuries.

关键词： Gradient scaffolds Musculoskeletal tissues Advanced manufacturing Biomaterials Tissue regeneration

Binuclear Ruthenium Complexes with Benzo[1,2-b;4,5-b＇]- dithiophene Analogues as Bridge Ligands： Syntheses, Characterization and Notable Difference on Electronic Coupling

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Chinese Journal of Chemistry 2017年第7期35卷 1170-1178页

作者： ya-ping Ou Shunlin Tang Aihui Wang Junhua Li Fuxing Zhang Zhifeng xu College of Chemistry and Material Science Hengyang Normal University Key Laboratory of Functional Organo-metallic Materials of Hengyang Normal University College of Hunan ProvinceHengyangHunan 421008China

Diruthenium ethynyl complexes 1--3 （1： 1,5-dithia-s-indacene-4,8-dione; 2： 4,8-diethoxybenzo[1,2-b：4,5- b＇]dithiophene; 3： 4,8-didodecyloxybenzo[1,2-b：4,5-b＇]dithiophene） have been synthesized by incorporating the re- spective conjugated heterocyclic spacer and characterized by NMR and elemental analysis. The effects of bridge ligands＇ properties on electronic coupling between redox-active ruthenium terminal groups were investigated by electrochemistry, UV/vis/near-IR and IR spectroelectrochemistry combined with density functional theory （DFT） and time-dependent DFT calculations. Electrochemistry results indicated that complexes 1--3 exhibit two fully re- versible oxidation waves, and complexes 2 and 3 with electron-rich and π-conjuagted bridge ligands are character- ized by excellent electrochemical properties. Furthermore, the larger v（C≡C） separation from the IR spectroelec- trochemical results of 2 and 3 and the intense NIR absorption features of singly oxidized species 2＋ and 3＋ re- vealed that their molecular skeletons have superior abilities to delocalize the positive charge. The spin density dis- tribution from DFT calculations proved the conclusions of this study.

关键词： bridge ligands ruthenium terminal groups spectroelectrochemistry electronic coupling

Synthesis and insecticidal evaluation of tetrahydroimidazo[1,2-a]pyridin-5(1H)-one derivatives

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Chinese Chemical Letters 2016年第1期27卷 7-10页

作者： xuan-Qi Liu ya-Qin Liu xu-Sheng Shao Zhi-ping xu Xiao-Yong xu Zhong Li Shanghai Key Lab of Chemistry Biology School of Pharmacy East China University of Science and Technology Shanghai 200237 China Shanghai Collaborative Innovation Center for Biomanufacturing Technology Shanghai 200237 China

A series of novel tetrahydroimidazo[1,2-a]pyridine-5（1H）-one derivatives containing a electronegative pharmacophore（=CNO_2） were synthesized via practical aza-ene reaction and characterized by ~1H NMR,^（13）C NMR,^（19）F NMR and HRMS. Preliminary bioassays showed that some of the target compounds exhibited good insecticidal activity against brown planthopper（Nilaparvata lugens） and cowpea aphids（Aphis craccivora） at 500 mg L^（-1）. Among them, compound 11 h was active against brown planthopper at100 mg L^（-1）. The insecticidal activities varied significantly depending on the types and patterns of the substituents, which provided guidance for further investigation on structure modifications.

关键词： Neonicotinoids Tetrahydroimidazo[1,2-a]pyridin-5(1H) one Configuration Insecticidal activity

Elimination of grapevine fleck virus and grapevine rupestris stem pitting-associated virus from Vitis vinifera 87-1 by ribavirin combined with thermotherapy

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Journal of Integrative Agriculture 2021年第9期20卷 2463-2470页

作者： HU Guo-jun DONG ya-feng ZHANG Zun-ping FAN xu-dong REN Fan Research Institute of Pomology Chinese Academy of Agricultural SciencesXingcheng 125100P.R.China

Vitis vinifera 87-1 plants infected by grapevine fleck virus(GFkV) and grapevine rupestris stem pitting-associated virus(GRSPaV) were used as the plant materials for virus elimination treatment. This study evaluated the effects of ribavirin at different concentrations(15 and 25 μg mL^(–1);R15 and R25, respectively), thermotherapy(37°C;T), and the combination of ribavirin and thermotherapy(R15+T and R25+T) on eliminating viruses from grapevine plants in vitro. Both R15 and R25 had phytotoxic effects and weakened plant growth. Thermotherapy positively affected the growth of grapevine plants. Plant height was significantly greater in T, R15+T, and R25+T than in CK, R15 and R25. The proportion of dead plants after T, R15+T, and R25+T was 51.4, 11.4, and 8.6%, respectively. The survival rates of regenerated plants after all treatments were >68.0%. Ribavirin concentration and treatment time were related to the regeneration of shoot tips and elimination efficiencies of the two viruses. The survival rates of plants after R15+T for 30, 40, and 50 days were 97.3, 90.7, and 74.4%, respectively. The elimination rates of GRSPaV from plants in the three time quantum were 55.6, 84.6, and 93.8%, respectively. The elimination rate of GFkV was 23.9% higher in R25(35/44) than in R15(25/45), and that of GRSPaV was 7.0% higher in R25 than in R15. The combination of thermotherapy and chemotherapy was found to have a positive effect on the eradication of GFkV and GRSPaV, and R25+T for 50 days was able to completely eliminate the two viruses from in vitro grapevines.

关键词： in vitro grapevine grapevine fleck virus(GFk V) grapevine rupestris stem pitting-associated virus(GRSPaV) chemotherapy thermotherapy virus elimination

Wettability between titanium-containing steels and TiN ceramic substrate

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Journal of Iron and Steel Research International 2023年第4期30卷 677-686页

作者： ya-cen Deng Hao Liu Min Zhang xu-bin Zhang Qiang-qiang Wang Sheng-ping He College of Materials Science and Engineering Chongqing Key Laboratory of Vanadium–Titanium Metallurgy and Advanced MaterialsChongqing UniversityChongqing 400044China Institute of Material Engineering and Technology Pangang Group Research Institute Co.Ltd.Panzhihua 617000SichuanChina

The wettability between TiN ceramic substrates and steels with various Ti contents was studied under an argon atmosphere at 1550℃ using a modified sessile drop *** electron probe microanalyzer and thermodynamic calculations were applied to investigate the interface between the steels and the TiN substrates as well as the surface of solidified steel *** measured apparent contact angles between the TiN substrates and steels were 96°,91°,and 146°,as the Ti content in the steel samples was 0.01,0.31,and 0.68 wt.%,*** reaction products were found at the interface,and only physical interactions *** wettability between high titanium steels(0.68 wt.%Ti)and TiN ceramic substrates should be evaluated from various perspectives,as many TiN particles existing in steel made the apparent contact angle increased significantly,deviating from the true value of contact angle.

关键词： Wettability Contact angle High-Ti steel TiN ceramic

Probabilistic Response and Short-Term Extreme Load Estimation of Offshore Monopile Wind Turbine Towers by Probability Density Evolution Method

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China Ocean Engineering 2022年第3期36卷 363-371页

作者： ZHANG Hui xu ya-zhou School of Building Services Science and Engineering Xi’an University of Architecture and TechnologyXi’an 710055China School of Civil Engineering Xi’an University of Architecture and TechnologyXi’an 710055China

A new analysis framework based on probability density evolution method(PDEM)and its Chebyshev collocation solution are introduced to predict the dynamic response and short-term extreme load of offshore wind turbine(OWT)towers subjected to random sea *** regard to the stochastic responses,random function method is employed to generate samples of sea elevation,the probability density evolution equation(PDEE)is solved to calculate time-variant probability density functions of structural *** the probabilistic load estimation,a FAST model of NREL 5MW offshore turbine is established to obtain samples of bending moment at the tower *** equivalent extreme event theory is used to construct a virtual stochastic process(VSP)to assess the short-term extreme *** results indicate that the proposed approach can predict time-variant probability density functions of the structural responses,and shows good agreement with Monte Carlo ***,the predicted short-term extreme load can capture the fluctuation at the tail of the extreme value distribution,thus is more rational than results from the typical distribution ***,the proposed method shows good adaptation,precision and efficiency for the dynamic response analysis and load estimation of OWT towers.

关键词： offshore wind turbine probability density evolution method Chebyshev collocation matrix exponential Monte Carlo

Using Energy Conditions to Distinguish Brane Models and Study Brane Matter

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Communications in Theoretical Physics 2008年第8期50卷 383-386页

作者： ping Yong-Li xu Li-Xin CHANG Bao-Rong LIU Hong-ya School of Physics and Optoelectronic Technology Dalian University of Technology Dalian 116024 China

Current universe （assumed here to be normal matter on the brahe） is pressureless from observations. In this case the energy condition is po ≥ 0 and po =O. By using this condition, brahe models can be distinguished. Then, assuming arbitrary component of matter in DGP model, we use four known energy conditions to study the matter on the brahe. If there is nonnormal matter or energy （for example dark energy with w 〈-1/3） on the brane, the universe is accelerated.

关键词： brane universe cosmology energy conditions

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Si:H薄膜的微结构及输运性质

太阳能学报 1989年第1期10卷 82-88页

作者：周心明郑家贵曾家玉黄天荃邱淑蓁蔡亚平徐晓菲冯良桓四川大学

用扫描电镜观察Si:H薄膜的剖面,发现用平板电极沉积的Si:H薄膜呈柱状结构,而用环形电极沉积的膜具有层状结构。喇曼谱和X射线谱表明,这两种结构对应于微晶相的存在。测定薄膜的暗电导与温度间的关系,发现薄膜的电导激话能为各向异性。... 详细信息

用扫描电镜观察Si:H薄膜的剖面,发现用平板电极沉积的Si:H薄膜呈柱状结构,而用环形电极沉积的膜具有层状结构。喇曼谱和X射线谱表明,这两种结构对应于微晶相的存在。测定薄膜的暗电导与温度间的关系,发现薄膜的电导激话能为各向异性。联系耦合方式讨论了薄膜的生长机制。

关键词： Si:H薄膜微结构输运性质