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Nano mesocellular foam silica（MCFs）:An effective adsorbent for removing Ni2+ from aqueous solution

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Water Science and Engineering 2019年第4期12卷 298-306页

作者： xiao-dong li Qing-zhou Zhai Department of Basic Science Jilin Jianzhu UniversityChangchun 130118China Research Center for Nanotechnology Changchun University of Science and TechnologyChangchun 130022China

Nano mesocellular foam silica(MCFs)was synthesized through the hydrothermal method in this *** X-ray diffraction and scanning electron microscopy were used to characterize the MCFs *** sample presented spherical particles and regular *** results of transmission electron microscopy showed that synthesized MCFs has a three-dimensional honeycomb pore structure,which aids in the adsorption of nickel ion(Ni^2+).The results of low-temperature nitrogen gas adsorption-desorption showed that the pore diameter of the synthesized MCFs was 19.6 *** impacts of pH,temperature,amount of adsorbent,initial concentration of Ni^2+,and contact time on the adsorption effect of Ni^2+ by MCFs were *** the optimized adsorption conditions,the adsorption rate reached 96.10%and the adsorption capacity was 7.69 mg/*** has been determined through the study of kinetics and adsorption isotherms that the adsorption of Ni^2+ by MCFs follows the pattern of the pseudo-second-order kinetic model,simultaneously belonging to the Freundlich adsorption *** thermodynamic results of adsorption showed that,when the temperature is between 25℃ and 45℃,the adsorption is a spontaneous exothermic reaction.

关键词： Nickel ion Adsorption MCFs Kinetics Thermodynamics Hydrothermal method Wastewater treatment

Dissipative preparation of multipartite Greenberger-Horne-Zeilinger states of Rydberg atoms

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Chinese Physics B 2021年第2期30卷 71-78页

作者： Chong Yang dong-xiao li xiao-Qiang Shao Center for Quantum Sciences and School of Physics Northeast Normal UniversityChangchun 130024China Center for Advanced Optoelectronic Functional Materials Research and Key Laboratory for UV Light-Emitting Materials and Technology of Ministry of EducationNortheast Normal UniversityChangchun 130024China School of Physics International Joint Laboratory on Quantum Sensing and Quantum MetrologyHuazhong University of Science and TechnologyWuhan 430074China

The multipartite Greenberger-Horne-Zeilinger(GHZ)states play an important role in large-scale quantum information *** utilize the polychromatic driving fields and the engineered spontaneous emissions of Rydberg states to dissipatively drive three-and four-partite neutral atom systems into the steady GHZ states,at the presence of the nextnearest neighbor interaction of excited Rydberg ***,the introduction of quantum Lyapunov control can help us optimize the dissipative dynamics of the system so as to shorten the convergence time of the target state,improve the robustness against the spontaneous radiations of the excited Rydberg states,and release the limiting condition for the strengths of the polychromatic driving *** the feasible experimental conditions,the fidelities of three-and four-partite GHZ states can be stabilized at 99.24%and 98.76%,respectively.

关键词： multipartite entanglement Lyapunov control Rydberg antiblockade quantum dissipation

Recent advances of computational aeroacoustics

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Applied Mathematics and Mechanics(English Edition) 2015年第1期36卷 131-140页

作者： xiao-dong li Min JIANG Jun-hui GAO Da-kai liN li liU xiao-yan li School of Energy and Power Engineering Beihang University Beijing Aeronautical Science & Technology Research Institute of Commercial Aircraft Corporation of China Beijing Institute of Space Launch Technology Research and Development Center China Academy of Launch Vehicle Technology

Computational aeroacoustics （CAA） is an interdiscipline of aeroacoustics and computational fluid dynamics （CFD） for the investigation of sound generation and propagation from various aeroacoustics problems. In this review, the foundation and research scope of CAA are introduced firstly. A review of the early advances and applications of CAA is then briefly surveyed, focusing on two key issues, namely, high order finite difference scheme and non-reflecting boundary condition. Furthermore, the advances of CAA during the past five years are highlighted. Finally, the future prospective of CAA is briefly discussed.

关键词： aeroacoustics computational aeroacoustics (CAA) high order finite difference scheme non-reflecting boundary condition

Optimizing inter-view prediction structures for multi-view video coding using simulated annealing

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Journal of Zhejiang University-Science C(Computers and Electronics) 2011年第2期12卷 155-162页

作者： Zheng ZHU dong-xiao li Ming ZHANG Institute of Information and Communication Engineering Zhejiang University Hangzhou 310027 China Zhejiang Provincial Key Laboratory of Information Network Technology Hangzhou 310027 China

New video applications, such as 3D video and free viewpoint video, require efficient compression of multi-view video. In addition to temporal redundancy, exploiting the inter-view redundancy is crucial to improve the performance of multi-view video coding. In this paper, we present a novel method to construct the optimal inter-view prediction structure for multi-view video coding using simulated annealing. In the proposed model, the design of the prediction structure is converted to the arrangement of coding order. Then, a simulated annealing algorithm is employed to minimize the total cost for obtaining the best coding order. This method is applicable to arbitrary irregular camera arrangements. As experiment results reveal, the annealing process converges to satisfactory results rapidly and the generated optimal prediction structure outperforms the reference prediction structure of the joint multi-view video model (JMVM) by 0.1-0.8 dB PSNR gains.

关键词： Multi-view video coding Prediction structure Simulated annealing

Dark energy： A brief review

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Frontiers of physics 2013年第6期8卷 828-846页

作者： Miao li xiao-dong li Shuang Wang Yi Wang Institute of Theoretical Physics Chinese Academy of Sciences Beijing 100190 China Kavli Institute for Theoretical Physics Key Laboratory of Frontiers in Theoretical Physics Beijing 100190 China Department of Modern Physics University of Science and Technology of China Heifei 230026 China Interdisciplinary Center for Theoretical Study University of Science and Technology of China Hefei 230026 China Department of Physics College of Sciences Northeastern University Shenyang 110004 China Homer L. Dodge Department of Physics Astronomy Univ. of Oklahoma W Brooks St. Norman OK 73019 USA Kavli Institute for the Physics and Mathematics of the Universe Todai Institutes for Advanced Study University of Tokyo 5-1-5 Kashiwanoha Kashiwa Chiba 27%8583 Japan Department of Physics McGill University Montrdal QC H3A 2T8 Canada

The problem of dark energy is briefly reviewed in both theoretical and observational aspects. In the theoretical aspect, dark energy scenarios are classified into symmetry, anthropie principle, tuning mechanism, modified gravity, quantum cosmology, holographic principle, back-reaction and phenomenologieal types. In the observational aspect, we introduce cosmic probes, dark energy related projects, observational constraints on theoretical models and model independent reconstructions.

关键词： dark energy theory observation

Depth-aided inpainting for disocclusion restoration of multi-view images using depth-image-based rendering

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2009年第12期10卷 1738-1749页

作者： Kai LUO dong-xiao li Ya-mei FENG Ming ZHANG Department of Information Science and Electronic Engineering Zhejiang University Hangzhou 310027 China

A new algorithm is proposed for restoring disocclusion regions in depth-image-based rendering （DIBR） warped images. Current solutions include layered depth image （LDI）, pre-filtering methods, and post-processing methods. The LDI is complicated, and pre-filtering of depth images causes noticeable geometrical distortions in cases of large baseline warping. This paper presents a depth-aided inpainting method which inherits merits from Criminisi＇s inpainting algorithm. The proposed method features incorporation of a depth cue into texture estimation. The algorithm efficiently handles depth ambiguity by penalizing larger Lagrange multipliers of flling points closer to the warping position compared with the surrounding existing points. We perform morphological operations on depth images to accelerate the algorithm convergence, and adopt a luma-first strategy to adapt to various color sampling formats. Experiments on test multi-view sequence showed that our method has superiority in depth differentiation and geometrical loyalty in the restoration of warped images. Also, peak signal-to-noise ratio （PSNR） statistics on non-hole regions and whole image comparisons both compare favorably to those obtained by state of the art techniques.

关键词： Depth-aided inpainting Disocclusion restoration Depth-image-based rendering (DIBR) Image warping Stereoscopic image Multi-view image 3D-TV

Cellular response to titanium discs coated with polyelectrolyte multilayer films

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International Journal of Minerals,Metallurgy and Materials 2014年第9期21卷 925-933页

作者： Jing Zhan Qiao-jie Luo Ying Huang xiao-dong li Department of Stomatology Sir Run Run Shaw Hospital College of Medicine Zhejiang University Department of Oral and Maxillofacial Surgery the Affiliated Stomatology Hospital College of Medicine Zhejiang University

The purpose of this study was to investigate the effects ofpolyelectrolyte multilayer （PEM） coatings on the biological behavior of titanium （Ti） substrates. Collagen type I/hyaluronic acid （Col/HA） and chitosan/hyaluronic acid （Chi/HA） multilayer PEM coatings were introduced onto Ti substrates using layer-by-layer assembly. Contact angle instruments and quartz crystal microbalance were used for film characterization. The results obtained showed that both Col/HA and Chi/HA surfaces had high hydrophilicity and promoted cell adhesion in MC3T3-E1 pre-osteoblast and human gingival fibroblast cells. In addition, the synthesis of function-related proteins and gene expression levels in both MC3T3-E1 and fibroblast cells was higher for the Col/HA coating compared with the Chi/HA coating, indicating better cellular response to the Col/HA coating.

关键词： titanium surface modification polyelectrolytes multilayer films cellular response

Synthesis and mesomorphic properties of bent-shaped molecule with low bent-angle central core and long alkylthio tail

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Chinese Chemical Letters 2011年第9期22卷 1111-1114页

作者： xiao dong li Mao Sheng Zhan Kai Wang School of Material Science and Engineering Beijing University of Aeronautics and Astronautics Beijing 100191 China

Two homologous series of bent-shaped molecules composed of low bent-angle naphthalene central core and long alkoxy tail or alkylthio tail, N（1,7）-n-OPIMB and N（1,7）-n-SP1MB （n = 20, 22）, respectively, were synthesized. The mesomorphic properties were investigated by differential scanning calorimetry （DSC）, polarizing optical microscopy （POM） and X-ray diffraction （XRD）. Compared to the direct transition from the isotropic phase to the chiral B4 phase examined in N（1,7）-n-OPIMB, N（1,7）-n-SPIMB exhibited a rare Iso-Ncol-Colh-B4 phase sequence. The combination of the asymmetric low bent-angle 1,7-naphathalene central core and the flexible long alkylthio tail is considered to play an important role in the formation of such a novel phase sequence.

关键词： Bent-shaped liquid crystal Alkylthio tail Mesomorphic behaviour

Performance evaluation of laponite as a mud-making material for drilling fluids

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Petroleum Science 2019年第4期16卷 890-900页

作者： Zheng-Qiang Xiong xiao-dong li Fan Fu Yan-Ning li Beijing Institute of Exploration Engineering

In this study, laponite was tested as a mud-making material for drilling fluids. Laponite is a synthetic smectite clay with a structure and composition closely resembling the natural clay mineral hectorite. Commercially available laponite was characterized by X-ray di ractometry, scanning electron microscopy and infrared spectrometry. Its dispersibility, salt resistance and high-temperature resistance were evaluated. The results showed that laponite possessed superior cation exchange capacity(140.4 mmol/100 g) with interlayer cations of Na^+ and li^+. Laponite could easily be dispersed in water to yield increased viscosity with no influence from hydration time or temperature. On the other hand, laponite dispersions displayed an excellent heat resistance, with invariant apparent viscosity at high temperatures. For instance, the apparent viscosity of the2 wt% laponite dispersion underwent changes between 22 and 24 mPa s after hot rolling at 180–240 °C for 16 h. Compared to existing mud-making materials, laponite exhibited better mud-making properties. Furthermore, laponite revealed good compatibility with other additives, and the water-based drilling fluids prepared with laponite as mud-making material showed an excellent stability at elevated temperatures and superior performance–cost ratios. Overall, these findings indicated that laponite had an excellent dispersibility at high temperatures and hence would have promising applications as high-temperature mud-making material for preparing water-based drilling fluids designed for ultra-high-temperature environments.

关键词： Laponite Mud-making material Dispersibility High-temperature tolerance Ultra-high-temperature water-based drilling fluids