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Ru-doped phosphorene for electrochemical ammonia synthesis

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Rare Metals 2020年第8期39卷 874-880页

作者： Jian-Dong liu Zeng-xi Wei Yu-Hai Dou Yue-Zhan Feng Jian-min Ma Advanced Catalytic Engineering Research Center of the ministry of Education School of Physics and ElectronicsHunan UniversityChangsha 410082China Centre for Clean Environment and Energy Gold Coast CampusGriffith UniversityGold Coast QLD 4222Australia Key Laboratory of Materials Processing and Mold(Zhengzhou University) Ministry of EducationZhengzhou UniversityZhengzhou 450002China

The electrochemical ammonia synthesis has attracted increasing attention due to its energy saving ***,developing novel electrocatalysts and their mechanism remain great ***,several transition metal(TM)atoms doped on phosphorene were studied as N2 fixation electrocatalysts by using density functional theory(DFT)*** results demonstrate that single Ru atom doped phosphorene shows an excellent catalytic activity for ammonia synthesis via the enzymatic pattern.A small overpotential of 0.696 V is achieved for this *** effect of oxidation in the catalyst was also discussed in our *** deactivates the catalyst,which should be avoided in the *** outcomes offer a novel perspective for single-atom catalytic ammonia synthesis with phosphorene as a substrate.

关键词： Phosphorene Nitrogen reduction reaction Doping Single-atom catalysis Ammonia synthesis

Spectacle correction of heterophoria in hyperopic amblyopic children

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Journal of Zhejiang University-Science B(Biomedicine & Biotechnology) 2006年第11期7卷 884-886页

作者： liu xi LI Yu-min LI Yang Ophthalmic Center the First Affiliated Hospital School of Medicine Zhejiang University Hangzhou 310003 China Department of Medicine University of Calgary Calgary Alberta T2N 4N1 Canada

Objective: To test the effects of corrective spectacles in hyperopic amblyopic children with heterophoria. Methods: Visual acuity, refraction and the amount of heterophoria on near (33 cm) fixation were measured before and after 3 weeks of spectacle-wearing in 30 hyperopic amblyopic children with heterophoria. The control group consisted of 20 emmetropic children age-matched to the patients. Results: Uncorrected eyes displayed hyperopic amblyopia accompanied by heterophoria. Corrective spectacles not only attenuated the hyperopia and amblyopia, but also changed the heterophoria to orthophoria. The amount of heterophoria before wearing spectacles was significantly different from that in emmetropic children; but after correction with spectacles, it was the same as that in the emmetropic controls. Conclusion: Correction with spectacles is effective for the treatment of heterophoria in hyperopic children with amblyopia.

关键词： Heterophoria Hyperopia Amblyopia Spectacles

Unveiling the dynamic instability mechanism of microstructure transformation in faceted oxide eutectic composite ceramics

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Journal of Materials Science & Technology 2023年第13期144卷 224-234页

作者： Haijun Su Yuan liu Qun Ren Zhonglin Shen min Guo xi Li Jun Zhang Lin liu Hengzhi Fu State Key Laboratory of Solidification Processing Northwestern Polytechnical UniversityXi’an 710072China Research&Development Institute of Northwestern Polytechnical University in Shenzhen Shenzhen 518057China Department of Material Science and Engineering Shanghai UniversityShanghai 200072China

Microstructure control is a great challenge in the high-temperature gradient directional solidification of eutectic composite ceramics due to the complex solidification ***,the microstructure trans-formation of faceted Al_(2)O_(3)/Er_(3)Al_(5)O_(12) thermal emission eutectic composite ceramics is explored over wide ranges of compositions(13.5 mol%-22.5 mol%Er_(2)O_(3))and solidification rates(2-200μm/s).Entirely cou-pled eutectics with primary phases suppressed are fabricated and the coupled zone is broadened in a wide range of 15.5 mol%-22.5 mol%Er_(2)O_(3) at low solidification *** competitive growth between eutectic and dendrite is evaluated on the basis of the maximum interface temperature *** ad-dition,the mechanisms of irregular eutectic spacing selection and adjustment under different solidifi-cation rates are revealed based on Magnin-Kurz model.A successful prediction of lamellar to rod-like eutectics is achieved associated with the dynamic instability of lamellar eutectic and the corresponding enlarged coexistence region is mapped based on the interface *** to the well mi-crostructure tailoring,the flexural strength of Al_(2)O_(3)/Er_(3)Al_(5)O_(12) eutectic composite ceramics has improved from 508 MPa up to 1800 MPa due to the refined eutectic spacing with low *** eutectic composite ceramics show strong selective optical absorption and the intensity increases with the refin-ing *** as-designed Al_(2)O_(3)/Er_(3)Al_(5)O_(12) composites with microstructural tailoring have great potential as integrations of structural and functional materials.

关键词： Directional solidification Laser floating zone melting Al_(2)O_(3)/Er_(3)Al_(5)O_(12)eutectic composite ceramics Eutectic growth mechanism Microstructure transformation

Improving hydrogen storage performance of Li–Mg–N–H system by adding niobium hydride

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Rare Metals 2014年第1期33卷 86-90页

作者： xi-Lin Zhu Shu-min Han xin Zhao Yuan Li Bao-Zhong liu College of Environmental and Chemical Engineering Yanshan University State Key Laboratory of Metastable Materials Science and Technology Yanshan University School of Materials Science and Engineering Henan Polytechnic University

Hydrogen storage MgH2-xNbH （x = 0 and 0.05） properties of 2LiNH2- composites and the catalysis of NbH on hydrogen sorption reaction of the Li-Mg- N-H system were investigated. Hydrogen sorption properties of 2LiNH2-MgH2 system are effectively improved by adding NbH. Temperature programmed desorption results show the addition of NbH reduces the dehydriding onset temperature of 2LiNH2-MgH2 system by 21 K. Approximate 3.62 wt% hydrogen in 2LiNH2-MgHz- 0.05NbH composite is released following a 500 min at 433 K, whereas the amount of hydrogen desorption is only -3.16 wt% for the pristine system under the same condition. The sample with NbH exhibits higher dehydriding rate compared with the pristine one. Moreover, hydrogen absorption rate increases by adding NbH into the 2LiNH2- MgH2 system. Hydrogen absorption capacity of the samples with NbH is 3.23 wt% within 400 rain, which is higher than that of pristine sample. Fine NbH particles homogeneously distribute in the 2LiNH2-MgH2-0.05NbH composite, and catalyze the hydrogen sorption reaction rather than reacts as a reactant into new compound.

关键词： Hydrogen storage performances Li-Mg-N-H system Niobium hydride Kinetics

Ricci Curvature of Certain Submanifolds in Kenmotsu Space Forms

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Communications in Mathematical Research 2009年第4期25卷 340-348页

作者： liu JIAN-YU liu xi-min Department of Mathematics Linyi Normal University Linyi Shandong 276005 Department of Mathematics South China University of Technology Guangzhou 510640

In this paper, we obtain some sharp inequalities between the Ricci cur- vature and the squared mean curvature for bi-slant and semi-slant submanifolds in Kenmotsu space forms. Estimates of the scalar curvature and the... 详细信息

关键词： Kenmotsu space form Ricci curvature k-Ricci curvature bi-slant sub-manifold semi-slant submanifold

Enhanced Anti-corrosion Ability and Biocompatibility of PLGA Coatings on MgZnYNd Alloy by BTSE-APTES Pre-treatment for Cardiovascular Stent

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Journal of Materials Science & Technology 2016年第9期32卷 845-857页

作者： Jing liu Tingfei xi Center for Biomedical Materials and Tissue Engineering Academy for Advanced Interdisciplinary Studies Peking University Shenzhen Institute Peking University

Bioabsorbable magnesium alloys are widely studied for various implant applications, as they reduce the risks such as severe inflammatory response existing in permanent metallic implants. However, the over-fast corrosion rate of magnesium alloy is usually an obstacle in biomedical applications. Here we report a simple two-step reaction to introduce anticorrosive silane pre-treatment on MgZnYNd alloys before coating with poly （glycolide-co-lactide）（PLGA）. The first step is to immerse the NaOH-activated MgZnYNd with bistriethoxysilylethane （BTSE） to form a cross-linked silane coating layer with enhanced corrosion resistance; the second step involves immobilizing amine functional groups for forming hydrogen bond with outer PLGA coating by treating the BTSE-modified MgZnYNd with 3-amino-propyltrimethoxysilane （APTES）. We characterized the BTSE-APTES pre-treated PLGA coating on MgZnYNd by scanning electron microscopy （SEM）, Fourier transform infrared spectroscopy （FF-IR）, X-ray photoelectron spectroscopy （XPS）, static contact angle and Acid Orange 7 measurement. Nano-scratch test was to verify that the scratch resistance of the PLGA coating with BTSE-APTES pre-treatment was superior to direct PLGA coating. Stan-dard electrochemical measurements along with the long-term immersion results indicated that the BTSE- APTES pre-treatment rendered better in vitro degradation behavior. Cell adhesion and cell viability tests with both vascular smooth muscle cells （VSMC） and human umbilical vein endothelial cells （EA. hy926） demonstrated that BTSE-APTES pre-treated MgZnYNd substrate had significantly more beneficial effects. The favorable anti-corrosion behavior and biocompatibility of BTSE-APTES pre-treated PLGA coatings on MgZnYNd alloy suggest that the novel two-step silanization procedure may have the great potential to enhance the performance of the magnesium-based biomaterials and provide a valid solution for the conversion modification of cardiovascular implants, taking the

关键词： Cardiovascular stent SilanizationAnti-corrosion Cytocompatibility MgZnYNd alloy

Dynamic thermal management by greedy scheduling algorithm

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Journal of Central South University 2012年第1期19卷 193-199页

作者： QU Shuang-xi ZHANG min-xuan liu Guang-hui liu Tao School of Computer Science National University of Defense TechnologyChangsha 410073China

Chip multiprocessors(CMPs) allow thread level parallelism,thus increasing ***,this comes with the cost of temperature *** require more power,creating non uniform power map and *** at this problem,a thread scheduling algorithm,the greedy scheduling algorithm,was proposed to reduce the thermal emergencies and to improve the *** greedy scheduling algorithm was implemented in the Linux kernel on Intel's Quad-Core *** experimental results show that the greedy scheduling algorithm can reduce 9.6%-78.5% of the hardware dynamic thermal management(DTM) in various combinations of workloads,and has an average of 5.2% and up to 9.7% throughput higher than the Linux standard scheduler.

关键词： greedy scheduling algorithm chip multiprocessor thermal-aware

A nonlocal Burgers equation in atmospheric dynamical system and its exact solutions

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Chinese Physics B 2019年第1期28卷 189-194页

作者： xi-Zhong liu Jun Yu Zhi-Mei Lou xian-min Qian Institute of Nonlinear Science Shaoxing UniversityShaoxing 312000China Yuanpei College Shaoxing UniversityShaoxing 312000China

From a two-vortex interaction model in atmospheric and oceanic systems, a nonlocal counterpart with shifted parity and delayed time reversal is derived by a simple AB reduction. To obtain some approximate analytic solutions of this nonlocal system, the multi-scale expansion method is applied to get an AB-Burgers system. Various exact solutions of the AB-Burgers equation, including elliptic periodic waves, kink waves and solitary waves, are obtained and shown *** show the applications of these solutions in describing correlated events, a simple approximate solution for the two-vortex interaction model is given to show two correlated dipole blocking events at two different places. Furthermore, symmetry reduction solutions of the nonlocal AB-Burgers equation are also given by using the standard Lie symmetry method.

关键词： AB–BA equivalence principle nonlocal Burgers equation periodic waves

Global FLS-based Consensus of Stochastic Uncertain Nonlinear Multi-agent Systems

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International Journal of Automation and computing 2021年第5期18卷 826-837页

作者： Jia-xi Chen Jun-min Li School of Mathematics and Statistics Xidian UniversityXi'an 710071China

Using graph theory, matrix theory, adaptive control, fuzzy logic systems and other tools, this paper studies the leader-follower global consensus of two kinds of stochastic uncertain nonlinear multi-agent systems(MAS). Firstly, the fuzzy logic systems replaces the feedback compensator as the feedforward compensator to describe the uncertain nonlinear dynamics. Secondly, based on the network topology, all followers are divided into two categories: One is the followers who can obtain the leader signal, and the other is the follower who cannot obtain the leader signal. Thirdly, based on the adaptive control method, distributed control protocols are designed for the two types of followers. Fourthly, based on matrix theory and stochastic Lyapunov stability theory, the stability of the closed-loop systems is analyzed. Finally, three simulation examples are given to verify the effectiveness of the proposed control algorithms.

关键词： Fuzzy logic systems stochastic nonlinear multi-agent systems(MAS) consensus algorithm adaptive control