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Journal of Advanced Ceramics 2022年第1期11卷 75-93页

作者： Dake ZHAO Dongjiang WU Jing shi Fangyong NIU Guangyi MA Key Laboratory for Precision and Non-traditional Machining Technology of Ministry of Education Dalian University of TechnologyDalian 116024China

Melt-grown alumina-based composites are receiving increasing attention due to their potential for aerospace applications;however,the rapid preparation of high-performance components remains a ***,a novel route for 3D printing dense(<99.4%)high-performance melt-grown alumina-mullite/glass composites using directed laser deposition(DLD)is *** issues on the composites,including phase composition,microstructure formation/evolution,densification,and mechanical properties,are systematically *** toughening and strengthening mechanisms are analyzed using classical fracture mechanics,Griffith strength theory,and solid/glass interface infiltration *** is demonstrated that the composites are composed of corundum,mullite,and glass,or corundum and *** the increase of alumina content in the initial powder,corundum grains gradually evolve from near-equiaxed dendrite to columnar dendrite and cellular structures due to the weakening of constitutional undercooling and small nucleation *** microhardness and fracture toughness are the highest at 92.5 mol%alumina,with 18.39±0.38 GPa and 3.07±0.13 MPa-m1/2,*** maximum strength is 310.1±36.5 MPa at 95 mol%*** enhancement is attributed to the improved densification due to the trace silica doping and the relief of residual *** method unravels the potential of preparing dense high-performance melt-grown alumina-based composites by the DLD technology.

关键词： laser additive manufacturing alumina mullite microstructure mechanical properties

FDBST: Fast Discovery of Bursty Spatial-Temporal Topic

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Chinese Journal of Electronics 2020年第1期29卷 168-176页

作者： ZHU Chuangying DU Junping ZHANG Qiang shi Lei Lee JangMyung Beijing Key Laboratory of Intelligent Telecommunication Software and Multimedia School of Computer ScienceBeijing University of Posts and Telecommunications Research Institute of Computer Information and Communication Pusan National University

Discovering the hot topic among trends is an essential way to manage public opinion. But the dynamic property makes it a tough task as the existing methods of detection process are time-consuming. With the new Fast discovery of burst spatial-temporal topic(FDBST) method, the uptime of topic discovery is kept within one second and there is no sacrificing of topic quality, the noisy topics are all kept off, the time-varying problem and the sparsity problem are easily tackled by using spatial-temporal characteristics. How the FDBST works? It is triggered by a burst term based on social data trends, while the data is generated within a small time interval in a region while the irrelevant data is excluded during this process. By fusing the regional topics, the potential burst topic is *** experiments show the preferable effects of the FDBST and it is an outperforms state-of-the-art approaches in terms of effectiveness.

关键词： Social network Real-time Spatialtemporal Burst topic Data stream

Ionic liquids for high performance lithium metal batteries

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Journal of Energy Chemistry 2021年第8期30卷 320-333,I0007页

作者： Kexin Liu Zhuyi Wang Liyi shi Siriporn Jungsuttiwong shuai Yuan School of Materials Science and Engineering Shanghai University200444 ShanghaiChina Research Centre of Nanoscience and Nanotechnology Shanghai University200444 ShanghaiChina Center for Organic Electronic and Alternative Energy Department of Chemistry and Center of Excellence for Innovation in ChemistryFaculty of ScienceUbon Ratchathani University34190 Ubon RatchathaniThailand Emerging Industries Institute Shanghai UniversityJiaxing 314006China

The pursuit of high energy density has promoted the development of high-performance lithium metal ***,it faces a serious security *** liquids have attracted great attention due to their high ionic conductivity,non-flammability,and the properties of promoting the formation of stable SEI *** understanding the problems existing in lithium metal batteries and the role of ionic liquids in them is of great significance for improving the performance of lithium metal *** article reviews the effects of the molecular structure of ionic liquids on ionic conductivity,Li^(+)ion transference number,electrochemical stability window,and lithium metal anode/electrolyte interface,as well as the application of ionic liquids in Li-high voltage cathode batteries,Li-O_(2) batteries and Li-S *** molecular design,composition and polymerization will be the main strategies for the future development of ionic liquid-based electrolytes for high performance lithium metal battery.

关键词： Ionic liquids Li+ion conduction Interface issues Lithium metal battery

Anion-tuned nickel chalcogenides electrocatalysts for efficient 2e−ORR towards H_(2)O_(2)production in acidic media

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Nano Research 2023年第4期16卷 4729-4735页

作者： Qingjia Sun Guanxing Xu Bingyan Xiong Lisong Chen Jianlin shi Shanghai Key Laboratory of Green Chemistry and Chemical Processes School of Chemistry and Molecular EngineeringEast China Normal UniversityShanghai 200062China Institute of Eco-Chongming Shanghai 202162China State Key Laboratory of High Performance Ceramics and Superfine Microstructures Shanghai Institute of CeramicsChinese Academy of SciencesShanghai 200050China

Electrocatalytic 2e−oxygen reduction reaction(2e−ORR)is a promising approach to producing H_(2)O_(2) at ambient temperature and pressure especially in acidic media,which,however,is hindered by the high cost of precious metal-based ***,the development of efficient earth-abundant electrocatalysts and reaction mechanism exploration for H_(2)O_(2) production by 2e−ORR in acidic solution are critically important but remain challenging at *** this work,NiSe_(2)has been developed as a novel and high-performance 2e−ORR electrocatalyst in acidic media,moreover,using nickel chalcogenides as the models,the influence of different anion species(Se_(2)^(2−),S22−,and O^(2−))on 2e−ORR electrocatalytic performance of the catalysts has been *** synthesized NiSe_(2)exhibits outstanding 2e−ORR performance of high selectivity(90%)and long-term durability(12 h).The maximum H_(2)O_(2) concentration of NiSe_(2)reaches 988 ppm,which is the highest among all the reported transition metal *** work demonstrates a novel point of view in anion tuning for designing high-efficiency transition-metal-based electrocatalysts for 2e−ORR.

关键词： hydrogen peroxide oxygen reduction reaction electrosynthesis anions

Controlling assembly-induced symmetry-breaking by tuning the vortex-responsive nanostructures

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Nano Research 2023年第12期16卷 13450-13456页

作者： Chengxi Li Kang Huang Chen Xiao Yonghong shi Pengfei Duan CAS Key Laboratory of Nanosystem and Hierarchical Fabrication National Center for Nanoscience and Technology(NCNST)Beijing 100190China University of Chinese Academy of Sciences Beijing 100049China

The generation of chirality in supramolecular structures from achiral building blocks has remained a challenge for a long *** this study,we present a vortex-assisted chiral supramolecular polymerization from a series of achiral C3-symmetric monomers,where the mechanism of symmetry-breaking is systematically *** increasing the supersaturation,at the early stage of nucleation and growth,highly ordered assemblies can be generated as the initial chiral ***,chiral assemblies from high supersaturation are hard to interwind into clusters,where clusters as nuclei are not conducive to being fractured by sheer force of vortex ***,it is concluded that chiral assemblies in the nucleation stage possess low energy barrier,so that chiral nuclei could be fractured and replicated by the *** enlarging the initial chiral bias,the major chiral nuclei can evolute into the final chiral polymers.

关键词： supramolecular polymer symmetry-breaking chirality assembly vortex

Robotic-vs laparoscopic-assisted proctectomy for locally advanced rectal cancer based on propensity score matching: Short-term outcomes at a colorectal center in China

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World Journal of Gastrointestinal Oncology 2020年第4期12卷 424-434页

作者： Shan-Ping Ye Wei-Quan Zhu Dong-Ning Liu Xiong Lei Qun-Guang Jiang Hui-Min Hu Bo Tang Peng-Hui He Geng-mei Gao He-Chun Tang Jun shi Tai-Yuan Li Department of General Surgery First Affiliated Hospital of Nanchang UniversityNanchang 330006Jiangxi ProvinceChina Department of Graduate Student Jiangxi Medical College of Nanchang UniversityNanchang 330006Jiangxi ProvinceChina

BACKGROUND Reports in the field of robotic surgery for rectal cancer are increasing year by ***,most of these studies enroll patients at a relatively early stage and have small sample *** fact,studies only on patients with locally advanced rectal cancer(LARC)and with relatively large sample sizes are *** To investigate whether the short-term outcomes differed between robotic-assisted proctectomy(RAP)and laparoscopic-assisted proctectomy(LAP)for *** The clinicopathological data of patients with LARC who underwent robotic-or laparoscopic-assisted radical surgery between January 2015 and October 2019 were collected *** reduce patient selection bias,we used the clinical baseline characteristics of the two groups of patients as covariates for propensity-score matching(PSM)***-term outcomes were compared between the two *** The clinical features were well matched in the PSM *** with the LAP group,the RAP group had less intraoperative blood loss,lower volume of pelvic cavity drainage,less time to remove the pelvic drainage tube and urinary catheter,longer distal resection margin and lower rates of conversion(P0.05).The rates of total complications and all individual complications were similar between the RAP and LAP groups(P>0.05).CONCLUSION This retrospective study indicated that RAP is a safe and feasible method for LARC with better short-term outcomes than LAP,but we have to admit that the clinically significant of part of indicators are relatively small in the practical situation.

关键词： Rectal neoplasms Robotics Laparoscopy Proctectomy Treatment outcome

用于心脏电活动成像的空间滤波器输出噪声抑制方法

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物理学报 2018年第15期67卷 360-368页

作者：周大方张树林蒋式勤同济大学电子与信息工程学院上海201804 中国科学院上海微系统与信息技术研究所信息功能材料国家重点实验室上海200050

利用人体表面测量的心脏磁场数据无创成像心脏电活动,需要解决的关键问题是提高其重建分布电流源偶极矩强度的分辨率.本文在最小方差波束成形(MVB)方法的基础上,提出了一种可抑制空间滤波器输出噪声功率增益(SONG)的波束成形方法,目的... 详细信息

利用人体表面测量的心脏磁场数据无创成像心脏电活动,需要解决的关键问题是提高其重建分布电流源偶极矩强度的分辨率.本文在最小方差波束成形(MVB)方法的基础上,提出了一种可抑制空间滤波器输出噪声功率增益(SONG)的波束成形方法,目的是通过构造一种新的滤波器权矩阵,约束空间滤波器的输出噪声功率增益,提高重建分布电流源偶极矩强度的分辨率,即分布电流源空间谱估计的源分辨能力,从而增强心脏电活动磁成像的分辨率.文中给出了电流源重建的理论分析和仿真结果;比较了该方法与MVB方法的差别;并给出了两个健康人36通道心脏磁场数据的电活动成像.结果表明,SONG方法分辨电流源的能力较强,能够观察到心脏电磁场信号R峰时刻健康人的心室电活动较强,心房电活动较弱等特征.

关键词：心脏电活动成像心磁图逆问题波束成形

Rock breaking performance of the newly proposed unsubmerged cavitating abrasive waterjet

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International Journal of Mining Science and Technology 2023年第7期33卷 843-853页

作者： Chenxing Fan Haitao Zhang Yong Kang Hanqing shi Deng Li Hubei Key Laboratory of Waterjet Theory and New Technology Wuhan UniversityWuhan 430072China School of Power and Mechanical Engineering Wuhan UniversityWuhan 430072China

To improve the rock breaking ability, cavitating waterjet and abrasive waterjet are combined by using a coaxial low-speed waterjet generated around the periphery of a high-speed abrasive waterjet, and a new type of waterjet called unsubmerged cavitating abrasive waterjet(UCAWJ) is thus produced. The rock breaking performance of UCAWJ was compared with submerged cavitating abrasive waterjet(SCAWJ)and unsubmerged abrasive waterjet(UAWJ) by impinging sandstone specimens. Moreover, the effects of jet pressure, standoff distance, abrasive flow rate and concentration were studied by evaluating the specific energy consumption, and the area, depth, and mass loss of the eroded specimen. The results show that the artificially generated submerged environment in UCAWJ is able to enhance the rock breaking performance under the same operating parameters. Furthermore, the rock breaking performance of UCAWJ is much better at higher jet pressures and smaller standoff distances when compared with UAWJ. The greatest rock breaking ability of UCAWJ appears at jet pressure of 50 MPa and standoff distance of 32 mm, with the mass loss of sandstone increased by 370.6% and the energy dissipation decreased by 75.8%. In addition, under the experimental conditions the optimal abrasive flow rate and concentration are 76.5 m L/min and 3%, respectively.

关键词： Rock breaking Abrasive waterjet Unsubmerged cavitation Erosion Specific energy consumption

Second phase refining induced optimization of Fe alloying in Zn:Significantly enhanced strengthening effect and corrosion uniformity

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International Journal of Minerals,Metallurgy and Materials 2022年第4期29卷 796-806页

作者： Zhangzhi shi Changheng Li Meng Li Xiangmin Li Luning Wang Beijing Advanced Innovation Center for Materials Genome Engineering Key Laboratory for Advanced Materials Processing of Ministry of EducationBeijing Laboratory of Metallic Materials and Processing for Modern TransportationSchool of Materials Science and EngineeringUniversity of Science and Technology BeijingBeijing 100083China

Many non-toxic alloying elements,such as Fe,Ca,and Sr,have negligible solid solubilities in Zn matrix,leading to formation of coarse second phase *** exhibit low strengthening effects but highly detrimental to *** refining second phase is a common pursuit for Zn *** present paper takes Zn-0.3Fe alloy suffered from coarse FeZn_(13) second phase particles as a touchstone to testify microstructure refining effect through solidification with an accelerated speed and multi-pass ***_(13) particles are refined from 24 to 2μm,and Zn grains are refined to 5μ*** a result,the strengthening effect of Fe is enhanced significantly,with yield strength and the ultimate tensile strength of the alloy increased from 132 to 218 MPa and from 159 to 264 MPa,***,corrosion non-uniformity and penetration are much *** results show that microstructure refinement,especially on coarse intermetallic second phases,has a great potential to improve mechanical and degradation properties of biodegradable Zn alloys.

关键词： zinc alloys microstructure mechanical properties corrosion uniformity

Pursuing innovation in a new era

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Zoological Research 2024年第6期45卷 1232-1234页

作者： Yong-Gang Yao Peng shi Kunming Institute of Zoology Chinese Academy of SciencesKunmingYunnan 650223China

This year marks a significant milestone as we celebrate the75th anniversary of our nation,alongside the 65th anniversary of the Kunming Institute of Zoology(KIZ) and the 75^(th) anniversary of the Chinese Academy of Sciences(CAS).This juncture provides an opportunity to reflect on our progress over the past five years and strategically enhance our culture of innovation,while pursuing new aspirations(Yao & Shen,2019).It is a critical moment to advance innovation and take decisive steps toward leadership in this new era.

关键词： steps anniversary strategic