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Sol-gel derived bioactive hydroxyapatite/titania composite films on Ti6Al4V

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Journal of University of Science and Technology Beijing 2006年第5期13卷 469-475页

作者： Bing Su Guoqing Zhang xudong yu Chengtao Wang School of Mechanical and Power Energy Engineering Shanghai Jiaotong University Shanghai 200030 China Military Engineering Department Artillery Academy Hefei 230031 China

The composite films consisting of the titania gel impregnated with hydroxyapatite （HAP） submicron particles were prepared on commercial Ti6A14V plates processed by a sol-gel route. HAP powders were synthesized based on wet chemical precipitation method with Ca（NO3）2.4H2O and （NH4）2HPO4 as starting reagents. After being calcined at 900℃, HAP powders were ultrasonically scattered in ethanol to produce HAP sol. The titania sol was prepared using titanium （IV） isopropoxide {Ti[OCH（CH3）2]4} as precursor. Both the titania sol and the HAP/titania mixture were sequentially spin-coated on the substrates and calcined at various temperatures. The characteristics and mechanical adhesion of the composite films were investigated. The results show that the as-prepared films are dense, homogeneous, well-crystallized, and there is a good interfacial adhesion between the film and the substrate. The in vitro bioactivities of these films were discussed based on the analysis of the variations of Ca and P concentrations in the simulated body fluid and their surface morphologies against immersion time.

关键词： titania hydroxyapatite composite film sol-gel route

Characterization of squeezed states with controllable coherent light injection at sidebands

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Science China(Physics,Mechanics & Astronomy) 2017年第5期60卷 73-76页

作者： Wei Li yuanBin Jin xudong yu State Key Laboratory of Quantum Optics and Quantum Optics Devices Institute of Opto-ElectronicsShanxi UniversityTaiyuan 030006China Collaborative Innovation Center of Extreme Optics Shanxi UniversityTaiyuan 030006China

The squeezed state was experimentally produced in the four wave mixing process for the first time thirty years ago [1]. Its intrinsic nonclassical property has always attracted the attention of the scientists, and it has also presented an unpredictable application potential in quantum information pro- cessing [2-6] and quantum metrology [7-9]. For gaining an insight into the quantum state, Bertrand et al. [10] intro- duced the concept of quantum tomography into quantum mechanics in 1987. And in 1997, Breitenbach et al. [11] pre- sented the noise distribution of the squeezed states of light fields and reconstructed the quantum states by balanced homodyne detection （BHD）. If the squeezed state light field has a relatively strong amplitude, BHD is not suitable. Consequently, other approaches have also been studied, such as self-tomography of the twin-beam state [12] and selftomography of the single-mode squeezed light field with an empty cavity [ 13]. These approaches enable people to understand the nature of the quantum state.

关键词：压缩态光场特性表征光注入相干可控量子信息平衡零拍探测非经典特性

Suppression of the G-sensitive drift of laser gyro in dual-axis rotational inertial navigation system

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Journal of Systems Engineering and Electronics 2021年第4期32卷 822-830页

作者： yu xudong WANG Zichao FAN Huiying WEI Guo WANG Lin College of Advanced Interdisciplinary Studies National University of Defense TechnologyChangsha 410073China

The dual-axis rotational inertial navigation system(INS)with dithered ring laser gyro(DRLG)is widely used in high precision *** major inertial sensor errors such as drift errors of gyro and accelerometer can be averaged out,but the G-sensitive drifts of laser gyro cannot be averaged out by indexing.A 16-position rotational simulation experiment proves the G-sensitive drift will affect the long-term navigation error for the rotational INS *** vibration coupling and asymmetric structure of the DRLG are the main errors.A new dithered mechanism and optimized DRLG is *** validity and efficiency of the optimized design are conformed by 1 g sinusoidal vibration *** optimized inertial measurement unit(IMU)is formulated and measured *** and vehicle experimental results show that the divergence speed of longitude errors can be effectively slowed down in the optimized *** long term independent navigation,the position accuracy of dual-axis rotational INS is improved close to 50%,and the G-sensitive drifts of laser gyro in the optimized IMU are less than 0.0002°/*** results have important theoretical significance and practical value for improving the structural dynamic characteristics of DRLG INS,especially the highprecision inertial system.

关键词： inertial navigation rotational inertial navigation system(INS) laser gyro G-sensitive drift

The effect of temperature on phase equilibria of polyethylene glycol(PEG8000)-K_(2)SO_(4)-H_(2)O at T=(288.15,298.15,308.15)K

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Chinese Journal of Chemical Engineering 2020年第12期28卷 3079-3085页

作者： Shuai Chen Niancu Chen Hong Zheng xudong yu Ying Zeng College of Materials and Chemistry&Chemical Engineering Mineral Resources Chemistry Key Laboratory of Sichuan Higher Education InstitutionChengdu University of TechnologyChengdu 610059China

The phase behavior of potassium sulfate(K_(2)SO_(4))in polyethylene glycol with molecular weight 8000(PEG8000)andwater(H_(2)O)mixed solvent at 288.15,298.15,and 308.15 Kwere *** to the results,when the temperature are 288.15 and 298.15 K,there is only a solid-liquid phase equilibrium relationship in the system,and the phase diagrams are both divided into three parts which respectively are the regions of unsaturated homogeneous liquid(L),one liquid and one solid K_(2)SO_(4)(L+S)and one liquid and twosolids K_(2)SO_(4) and PEG8000(L+2S).The solubility of K_(2)SO_(4) in PEG8000-H_(2)O mixed solvent decreased with the addition of the PEG8000 in the *** the diagrams of 288.15 and 298.15 K,the sizes of regions of(L)and(L+S)increased and that of(L+2S)decreased with the increase of *** at 308.15 K,solid-liquid and liquid-liquid equilibrium coexist,and there are six parts in the complete phase diagram at 308.15 K,adding the areas of one liquid and one solid K_(2)SO_(4)(L+S),two liquids(2 L),two liquids and one solid K_(2)SO_(4)(2 L+S).The equations developed by Merchuk,Hu,and Jayapalwere used to fit the binodal curves data of the systemat 308.15 K,meanwhile,the experimental tie-line data of the system at 308.15 K were correlated by Othmer-Tobias equation and Bancroft equation.

关键词： K2SO4 Phase diagram Solubility Mixed solvent Multitemperature

Self-healable,Eu^(3+)-based polymeric gels containing terpyridyl groups with tunable luminescence based on ion recognition

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Journal of Rare Earths 2020年第7期38卷 705-710,I0001页

作者： Shenglu Wang Yajuan Li Fengjuan Shen Tao Wang xudong yu Hebei Research Center of Pharmaceutical and Chemical Engineering College of ScienceHebei University of Science and TechnologyShijiazhuang 050080China

Novel luminescent materials that change their emission colors in responding to external stimuli have attracted increasing attentions in the past ***,we report the preparation of a novel kind of Eu3+-based polymeric organogel with three *** dynamic coordination interactions,the organogel shows fast self-healing and adjustable fluorescent emission properties in the presence of different metal ions via coordination interaction competition *** coordination interaction also endows the gel with multiple stimuli-responsive properties such as water,base and *** multistimuli responsive fluorochromic organogel demonstrates a new way of preparing optical materials and bio-relevant sensors.

关键词： Polymer gel Rare earth Stimuli-responsive

Free radical oxidation reaction for selectively solvatochromic sensors with dynamic sensing ability

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Chinese Chemical Letters 2020年第7期31卷 1919-1922页

作者： Fengjuan Shen Tao Wang xudong yu Yajuan Li College of Science Hebei University of Science and TechnologyShijiazhuang 050080China

A novel BODIPY(boradiazaindacene) dye denoted as BODIPY-DT containing terpyridine unit has been designed and *** dye is found to be selective and visual solvatochromic sensor toward DMF among test organic *** sensing process displays time-controllable,dynamic signal outputs in the emission colors including red,purple,yellow and even white emission *** is presented that selective free radical oxidation reaction happens during the recognition process.

关键词： Solvent sensor BODIPY Dynamic sensing Photosensitizer

Mode splitting of a cavity with a high-density birefringence rubidium vapor in the superstrong coupling regime

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Science China(Physics,Mechanics & Astronomy) 2014年第7期57卷 1283-1288页

作者： CHEN LiangChao yu xudong MENG ZengMing ZHANG Jing State Key Laboratory of Quantum Optics and Quantum Optics Devices Institute of Opto-ElectronicsShanxi University

The mode splitting in a system with Doppler-broadened high-density two-level atoms in the presence of magnetic field inside a relatively long optical cavity is studied in the superstrong coupling regime(atoms-cavity coupling strength g√N is near or larger than the cavity free-spectral range?FSR).The effect of a magnetic field applied along the quantization axis is used to break the polarization degeneracy of the cavity and thereby introduce birefringence(or Faraday rotation)into the *** cavity modes are further split in the presence of the magnetic field compared with the normal case of the multi-normal-mode splitting of the two-level system near the D2 line *** dependence of the mode splitting on the magnetic field and the temperature is *** theoretical analysis according to the linear dispersion theory can provide a good explanation.

关键词： superstrong coupling normal-mode splitting Zeeman effect birefringence

Ensemble successor representations for task generalization in offline-to-online reinforcement learning

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Science China(Information Sciences) 2024年第7期67卷 240-255页

作者： Changhong WANG xudong yu Chenjia BAI Qiaosheng ZHANG Zhen WANG Space Control and Inertial Technology Research Center Harbin Institute of Technology Shanghai Artificial Intelligence Laboratory Shenzhen Research Institute of Northwestern Polytechnical University School of Cybersecurity Northwestern Polytechnical University

In reinforcement learning(RL), training a policy from scratch with online experiences can be inefficient because of the difficulties in exploration. Recently, offline RL provides a promising solution by giving an initialized offline policy, which can be refined through online interactions. However, existing approaches primarily perform offline and online learning in the same task, without considering the task generalization problem in offline-to-online adaptation. In real-world applications, it is common that we only have an offline dataset from a specific task while aiming for fast online-adaptation for several tasks. To address this problem, our work builds upon the investigation of successor representations for task generalization in online RL and extends the framework to incorporate offline-to-online learning. We demonstrate that the conventional paradigm using successor features cannot effectively utilize offline data and improve the performance for the new task by online fine-tuning. To mitigate this, we introduce a novel methodology that leverages offline data to acquire an ensemble of successor representations and subsequently constructs ensemble Q functions. This approach enables robust representation learning from datasets with different coverage and facilitates fast adaption of Q functions towards new tasks during the online fine-tuning *** empirical evaluations provide compelling evidence showcasing the superior performance of our method in generalizing to diverse or even unseen tasks.

关键词： offline reinforcement learning online fine-tuning task generalization successor representations ensembles

Optically levitated nanosphere with high trapping frequency

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Science China(Physics,Mechanics & Astronomy) 2018年第11期61卷 99-102页

作者： yuanBin Jin xudong yu Jing Zhang The State Key Laboratory of Quantum Optics and Quantum Optics Devices Institute of Opto-Electronics Shanxi University Synergetic Innovation Center of Quantum Information and Quantum Physics Shanxi University

The optically levitated object is intrinsically isolated from the thermal bath compared with the opto-mechanical oscillator connected to the thermal environment via the cantilever [1,2]. Thus the limitation of the thermalization and decoherence in- troduced by the cantilever is cancelled. The Q-factor of the system is predicted to approach 1012 and the system is extremely sensitive to some changes [3-6]. And it is expected to detect non-Newtonian gravity forces at very small scales [7], the impact of single air molecules [8], nanoscaie temperature [9], and magnetic spin resonance [10]. Importantly it can be used to test the fundamental physical problems.

关键词：光学频率空气分子物理问题热环境振荡器伸臂系统