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High Voltage 2021年第1期6卷 95-105页

作者： Nan Zhou Lingen Luo hui song Gehao Sheng Xiuchen Jiang Department of Electrical Engineering Shanghai Jiao Tong UniversityShanghaiChina

The performance of array‐based power equipment acoustic emission(AE)source direc-tional of arrival(DOA)estimation methods is decided by not only algorithm performance,but also the array hardware parameters,that is,array aperture,sensor number,and so *** the estimation performance by hardware approaches always leads to the increase in *** this study,an array virtual extension method based on high‐order cumulants is proposed which can improve the sensor array performance without the need for hardware change or extra *** to low‐order cumulants,the high‐order cumulants established from Taylor expansion contain higher order terms which are omitted in low order ***,they have more detailed directional information about the signal source to improve the DOA estimation ***,because high‐order cumulants contain information only for the non‐Gaussian components,the array after extension shows better anti‐Gaussian noise *** on the establishment method of the high‐order cumulant,two types of extension including aperture extension and sensor number extension are proposed for different application *** and field tests results show that the array directional resolution is improved around 40%by aperture extension and the spectrum sidelobe level is reduced about 14 dB by sensor extension.

关键词： power estimation hardware

Fabrication of periodically aligned vertical singlecrystalline anatase TiO2 nanotubes with perfect hexagonal open-ends using chemical capping materials

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Nano Research 2014年第1期7卷 104-109页

作者： hui song Kyubong Jo Bock Young Jung Gun Young Jung School of Materials Science and Engineering Gwangju Institute of Science and Technology (GIST) Gwangju Republic of Korea Department of Chemistry and Interdisciplinary Program of Integrated Biotechnology Sogang University Seoul Republic of Korea Department of General Dentistry College of Dentistry Yonsei University Seoul Republic of Korea

A vertically aligned anatase TiO2 （A-TiO2） nanotube array has been fabricated by coating a ZnO nanorod （NR） template with a TiO2 precursor solution. After coating, the ZnO NR cores were selectively etched in an acidic environment to form TiO2 nanotubes （NTs）. More specifically, after growing the ZnO NRs via a hydrothermal method, one drop of the TiO2 precursor solution was cast to coat the ZnO NRs, the tops of which were previously covered with chemical capping materials by electrostatic interaction, and then the sample was sintered. Finally, the sample was immersed in an acidic solution resulting in selective etching of the ZnO NR cores. Thus, only TiO2 NTs remained on the substrate. The capping material is effectively used to create a perfect, hexagonal open-ended TiO2 NT array, which interestingly extends onset absorption towards the visible region.

关键词： TiO2 nanotubes chemical capping material ZnO nanorod template laser interferencelithography

Cocatalysts in photocatalytic methane conversion: recent achievements and prospects

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Science China Chemistry 2023年第9期66卷 2532-2557页

作者： Chengcheng Zhang Jing Wang Shenshen Ouyang hui song Jinhua Ye Li Shi School of Materials Science and Chemical Engineering Ningbo UniversityNingbo 315211China Zhejiang Key Laboratory of Bio-based Polymeric Materials Technology and Application Ningbo Key Laboratory of Polymer MaterialsNingbo Institute of Materials Technology and EngineeringChinese Academy of SciencesNingbo 315201China International Center for Materials Nanoarchitectonics(WPI-MANA) National Institute for Materials Science(NIMS)Tsukuba 305-0044Japan TJU-NIMS International Collaboration Laboratory School of Material Science and EngineeringTianjin UniversityTianjin 300072China

Photocatalysis, which performed under mild conditions by utilizing solar energy, has become a desirable technology to convert methane into highly valuable chemicals, such as methanol, ethane, and other hydrocarbons. However, pristine photocatalysts still suffer from the low utilization efficiency of solar light and the high recombination rate of photogenerated charge carriers, which exhibit the low activity and selectivity for photocatalytic methane conversion. Loading cocatalysts on photocatalysts is an attractive strategy to manipulate the products' yield and selectivity of photocatalytic methane conversion due to the enhanced charge carrier separation efficiency, extended light absorption and promoted reactant adsorption/desorption kinetics. This review discusses the recent achievements of the cocatalysts for photocatalytic methane conversion reactions. Moreover, the challenges and perspectives for the development of efficient cocatalysts are presented. This review provides considerable guidelines for the design and construction of efficient cocatalysts for photocatalytic methane conversion reactions.

关键词： photocatalysis methane conversion cocatalysts valuable chemicals

Intelligent learning approach for UHF partial discharge localisation in air-insulated substations

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High Voltage 2020年第5期5卷 583-590页

作者： Quanfu Zheng Lingen Luo hui song Gehao Sheng Xiuchen Jiang Department of Electrical Engineering Shanghai Jiao Tong UniversityNo.800 Dongchuan RoadShanghaiPeople's Republic of China

To achieve comprehensive insulation deterioration motoring of power equipment and early fault warning in air-insulated substations,a data-driven partial discharge(PD)source localisation method employing noisy ultra-high frequency(UHF)received signal strength indicator(RSSI)and particle filter is proposed in this *** with the existing UHF time-difference-based techniques,UHF wireless sensor arrays and RSSI-based methods provide an economical and high-adaptability ***,owing to the multi-pathing and shadowing effects,UHF signal attenuation cannot be ***,a Kalman filter was employed to smoothen the RSSI ***,a semi-parametric regression model is proposed to achieve a more accurate relationship between the RSSI and the transmission ***,in contrast to traditional localisation algorithms directly based on the RSSI ranging model,a particle filter was used to achieve higher *** predicted the best distribution of the position of PD by learning and considering all the system states of the previous *** laboratory test was performed within an area of 6 m×6 m,and the results demonstrate that the mean PD source localisation error was 1.16 m,which gives a potential application for the identification of power equipment with insulation deterioration in a substation,while the accuracy is still needed to be verified further by field tests.

关键词： RSSI local insulation

Syntheses, Structures, and Properties of Five Coordination Polymers Involving Phthalic Acid

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Chemical Research in Chinese Universities 2011年第5期27卷 724-729页

作者： WU Li-li HE Rong WEI Zhen song hui-hua College of Chemistry and Material Sciences Hebei Normal University Shijiazhuang 050016 t~ R. China

Five new coordination polymers Cu（phen）（H2O）（phth）·CH3OH（1）, [Cu（2,2′-bipy）（H2O）]（phth）·3.5H2O（2）, Zn（phen）（phth）（H2O）·1.125H2O（3） and [M（4,4′-bipy）（H2O）2]（phth）·2H2O[M=Zn（4）, Mn（5）]（H2phth=phthalic acid, bipy=bipyridine, phen=1,10-phenanthroline） have been synthesized from the amino acid derivatives（phthalyl-l- valine, H2L） and structurally characterized. H2L was hydrolyzed into phth2- group during the reaction, but the strucure feature was different from that of the complex directly synthesized from H2phth in the reported literature, revealing that H2L played an important role in composing the novel compounds. Compounds 1, 2 and 3 are all 1D chains, but the differences are that compound 1 is further hydrogen-bonded into 2D networks, and compound 2 is further extended into 3D supramolecular network through π-π stacking and hydrogen-bonding interactions. However, compound 3 is a 1D helix chain structure and further links into 2D networks through π-π stacking. Compounds 4 and 5 are isostructural and exhibit the same 2D layers, which are further connected by hydrogen-bonding interactions to form 3D supramolecular network. Antiferromagnetic superexchange was observed for compounds 1, 2 and 5.

关键词： Crystal structure Amino acid derivative Phthalic acid Coordination polymer

DETERMINATION OF ROCK-BREAKING PERFORMANCE OF HIGH-PRESSURE SUPERCRITICAL CARBON DIOXIDE JET

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Journal of Hydrodynamics 2012年第4期24卷 554-560页

作者： DU Yu-kun WANG Rui-he NI Hong-jian LI Mu-kun song Wei-qiang song hui-fang College of Petroleum Engineering China University of Petroleum(East China)Qingdao 266580China

In this study, a well-designed experimental setup is used to determine the rock-breaking performance of a high-pressure supercritical carbon dioxide （SC-CO2） jet. Its rock-breaking performance is first compared with that of a high-pressure water jet under the same operation conditions. The effects of five major factors that affect the rock-breaking performance of the high-pressure SC-CO2 jet, i.e., the nozzle diameter, the standoff distance, the jet pressure, the rock compressive strength and the jet temperature are experimentally determined. The experimental results indicate that the rock-breaking performance of the SC-CO2 jet is significantly improved over the high-pressure water jet. It is also found that the rock-breaking performance of the SC-CO2 jet is improved with the increase of the nozzle diameter or the standoff distance, until the nozzle diameter or the standoff distance reaches a certain critical value and after that it begins to deteriorate. The rock-breaking performance of the SC-CO2 jet improves monotonically with the increase of the jet pressure, while it shows a monotonic deterioration with the increase of the rock compressive strength. In addition, it is found that, under the same working conditions, the SC-CO2 jet can always provide a better rock-breaking performance than the subcritical liquid CO2 jet.

关键词： supercritical carbon dioxide drilling engineering rock-breaking performance

Comparison of pseudophakic retinal straylight in spherical/aspherical and hydrophobic/hydrophilic intraocular lens

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International Journal of Ophthalmology(English edition) 2015年第6期8卷 1146-1150页

作者： Yong Tang hui song Jing Chen Xin Tang Cataract Center Tianjin Eye Hospital

AIM: To study the potential reasons of increased straylight in pseudophakic eyes. METHODS: Cross -sectional study. Seventy patients diagnosed as bilateral age-related cataract and implanted with Tecnis ZA9003, Sensar AR40e, SA6OAT, XLSTABI ZO or Akeros AO intraocular lens (IOL) were enrolled in this research. Straylight was measured by a C -Quant straylight meter three to four weeks postoperatively. Five different modalities of IOL, including spherical/aspherical optics and hydrophobic/hydrophilic material were tested in this study. Normal as well as dilated pupils were used. The main outcome variable for straylight measurement was the logarithmic straylight parameter, log(s). RESULTS: The straylight parameter increased significantly after pupil dilation (P<0.05). Straylight of aspherical IOL was significantly higher after pupil dilation (P<0.06) compared to spherical IOL. In normal pupil, straylight of hydrophobic IOL was significant higher when compared with hydrophilic IOL (P<0.05). CONCLUSION: Straylight and visual acuity stand for the different aspects of visual function. Several factors including pupil diameter, optic material, aspherical design of IOL influence intraocular light scattering in pseudophakic eyes. Further investigation was needed to study the impact of optic material and optic surface design on pseudophakic straylight.

关键词： light scattering retinal straylight pseudophakia

Model-based cross-layer monitoring and adaptation of multilayer systems

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Science China(Information Sciences) 2013年第8期56卷 6-20页

作者： song hui RAJ Amit HAJEBI Saeed CLARKE Aidan CLARKE Siobhn Lero:The Irish Software Engineering Research Centre School of Computer Science and Statistics Trinity College Dublin Dublin 2 Ireland IBM Software Ireland Laboratory

With the vision of "Internet as a computer", complex software-intensive systems running on the Internet, or the "Internetwares", can be also divided into multiple layers. Each layer has a different focus, implementation technique, and stakeholders. Monitoring and adaptation of such multilayer systems are challenging, because the mismatches and adaptations are interrelated across the layers. This interrelation makes it difficult to find out: 1) When a system change causes mismatches in one layer, how to identify all the cascaded mismatches on the other layers? 2) When an adaptation is performed at one layer, how to find out all the complementary adaptations required in other layers? This paper presents a model-based approach towards cross-layer monitoring and adaptation of multilayer systems. We provide standard meta-modelling languages for system experts to specify the concepts and constraints separately for each layer, as well as the relations among the concepts from different layers. Within each individual layer, we use run-time models to represent the system state specific to this layer, monitor the systems by evaluating model changes according to specified constraints, and support manual or semi-automated adaption by modifying the models. When a change happens in the run-time model for one layer, either caused by system changes or by the adaptation, we synchronize the models for other layers to identify cascaded mismatches and complementary adaptations across the layers. We illustrate the approach on a simulated crisis management system, and are using it on a number of ongoing projects.

关键词： multilayer systems monitoring dynamic adaptation model driven engineering bidirectional model transformation

Long-term results of clear lens extraction combined with piggyback intraocular lens implantation to correct high hyperopia

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International Journal of Ophthalmology(English edition) 2013年第5期6卷 650-655页

作者： Xia Hua Xiao-Yong Yuan hui song Xin Tang Tianjin Medical University Tianjin Key Lab of Ophthalmology and Visual Science Tianjin Eye InstituteTianjin Eye HospitalClinical College of OphthalmologyTianjin Medical University Clinic Barraquer of Ophthalmology

AIM:To assess the refractive outcome of clear lensectomy combined with piggyback intraocular lens implantation in highly hyperopic ***:This case review included 19 eyes of 10 patients with high hyperopia and axial length less than *** lens power was calculated for emmetropia using the Holladay II formula in 17 eyes,and SRK/T formula in 2 eyes following clear lens extraction and piggyback intraocular lens *** were examined periodically over 24 months for visual acuity and spherical equivalent(SE).RESULTS:The mean postoperative SE at 24 months was 0.20±1.39D(range,-3.00 to 2.50D),better than preoperative 9.81±2.62D(range,+6.00 to +14.50D)(P<0.001).Five eyes had SE within±0.5D of emmetropia and 11 eyes within±1.00D at postoperative 24 *** mean postoperative uncorrected visual acuity(UCVA) at 24 months was 0.60±0.36,significantly improved compared to preoperative 1.39±0.33(P<0.001).The mean best-corrected visual acuity(BCVA) at 24 months was 0.49±0.35,not statistically different compared to preoperative 0.38±0.30(P=0.34).Twelve eyes maintained and 1 gained 1 or more Snellen line of BCVA,4 eyes lost 1 line,and 2 eyes lost 2 lines at 24 postoperative *** eyes best-corrected near visual acuity (BCNVA) achieved J1 at postoperative 24 months compared to preoperative 7 eyes and the other 7 eyes better than ***:Clearlensextractioncombinedpiggyback intraocular lens implantation appears to be an effective procedure to correct high hyperopia but mild overcorrection and intralenticular opacification may require secondary procedure.

关键词： piggyback intraocular lens high hyperopia

Phase Behavior and Interfacial Properties of Diblock Copolymer- Homopolymer Ternary Mixtures： Influence of Volume Fraction of Copolymers and Interaction Energy

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Chinese Journal of Polymer Science 2017年第7期35卷 874-886页

作者： Jian Wang Jian-hui song 卢宇源 Yong-jin Ruan Li-jia An State Key Laboratory of Polymer Physics and Chemistry Changchun Institute of Applied Chemistry Chinese Academy of Sciences Changchun 130022 China University of Chinese Academy of Sciences Beijing 100049 China School of Polymer Science and Engineering Qingdao University of Science and Technology Qingdao 266042 China

We use a Monte Carlo method to study the phase and interracial behaviors of A-b-B diblocks in a blend of homopolymers, A and B, which are confined between two asymmetric hard and impenetrable walls. Our results show that, when the interaction strength is weak, the block copolymers are uniformly distributed in the ternary mixtures under considered concentrations. Under strong interaction strength, distribution region of the block copolymers changes from a single smooth interface to a curved interface or multi-layer interface in the ternary mixtures. Furthermore, our findings show that with increasing volume fraction of A-b-B diblock copolymer （φc）, copolymer profiles broaden while φc ≥ 0.4, a lamellar phase is formed and by further increasing φc, more thinner layers are observed. Moreover, the results show that, with the increase of φc, the phase interface first gradually transforms from plane to a curved surface rather than micelle or lamellar phase while with the increase of the interaction between A and B segments （CAB）, the copolymer chains not only get stretched in the direction perpendicular to the interface, but also are oriented. The simulations also reveal that the difference between symmetric and asymmetric copolymers is negligible in statistics if the lengths of two blocks are comparable.

关键词： Ternary mixtures Phase behavior Interfacial property Copolymer compatibilizers Monte Carlo simulation