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Hepatobiliary & Pancreatic Diseases International 2024年第4期23卷 406-411页

作者： Jun-Fang Deng Chuan-Hui Peng Yu Zhang xiao-feng xu Rong-Liang Tong Zheng-Long Zhai Di-Yu Chen Cheng Zhang Li-Ming Wu Jian Wu Division of Hepatobiliary Pancreatic Surgery the First Affiliated HospitalZhejiang University School of MedicineHangzhou 310003China

Laparoscopic anatomical liver resection has been increasingly reported worldwide,but how to demarcate the resection planes is technically challenging[1].Positive staining technique with intraoperative indocyanine green(ICG)-fluorescence imaging has been introduced as an effective tool for real-time intraoperative guidance[2].Liver anatomy is ***,liver is composed of 9 segments,each is composed of two to three subsegments,and each subsegment contains several hepatic cone units.A hepatic cone unit is dominated by a tertiary or quaternary hepatic pedicles[3].

关键词： hepatic resection anatomy

AN EFFECTIVE CONTINUOUS ALGORITHM FOR APPROXIMATE SOLUTIONS OF LARGE SCALE MAX-CUT PROBLEMS

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Journal of Computational Mathematics 2006年第6期24卷 749-760页

作者： Cheng-xian xu xiao-liang feng-min xu Department of Mathematics Xi 'an Jiaotong University Xi ' an 710049 China

An effective continuous algorithm is proposed to find approximate solutions of NP-hard max-cut problems. The algorithm relaxes the max-cut problem into a continuous nonlinear programming problem by replacing n discrete constraints in the original problem with one single continuous constraint. A feasible direction method is designed to solve the resulting nonlinear programming problem. The method employs only the gradient evaluations of the objective function, and no any matrix calculations and no line searches are required. This greatly reduces the calculation cost of the method, and is suitable for the solution of large size max-cut problems. The convergence properties of the proposed method to KKT points of the nonlinear programming are analyzed. If the solution obtained by the proposed method is a global solution of the nonlinear programming problem, the solution will provide an upper bound on the max-cut value. Then an approximate solution to the max-cut problem is generated from the solution of the nonlinear programming and provides a lower bound on the max-cut value. Numerical experiments and comparisons on some max-cut test problems （small and large size） show that the proposed algorithm is efficient to get the exact solutions for all small test problems andwell satisfied solutions for most of the large size test problems with less calculation costs.

关键词： Max-cut problems Algorithm Feasible direction method Laplacian matrix,Eigenvectors.

Active metasurfaces for manipulatable terahertz technology

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Chinese Physics B 2020年第9期29卷 92-104页

作者： Jing-Yuan Wu xiao-feng xu Lian-Fu Wei Photonics Laboratory and Institute of Functional Materials College of ScienceDonghua UniversityShanghai 201620China Information Quantum Technology Laboratory School of Information Science and TechnologySouthwest Jiaotong UniversityChengdu 610031China

Metasurface is a kind of two-dimensional metamaterial with specially designed sub-wavelength unit *** consists of single-layer or few-layer stacks of planar structures and possesses certain superior abilities to manipulate the propagating electromagnetic waves,including the terahertz(THz)*** with the usual passive THz metasurfaces whose optical properties are difficult to be controlled after fabrication,the active materials are highly desirable to enable dynamic and tunable control of THz *** this review,we briefly summarize the progress of active THz metasurfaces,from their physical mechanisms on carrier concentration modulations,phase transitions,magneto-optical effects,etc.,for various possible THz applications mainly with low-dimensional materials,vanadium dioxide films,and superconductors.

关键词： metamaterial active metasurface terahertz wave modulations

Research on the Construction of a Novel Cyberspace Security Ecosystem

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Engineering 2018年第1期4卷 47-52页

作者： xiao-Niu Yang Wei Wang xiao-feng xu Guo-Rong Pang Chun-Lei Zhang Science and Technology on Communication Information Security Control Laboratory Jiaxing Zhejiang 314033 China Science and Technology on Electro-Optical Information Security Control Laboratory Tianfin 300300 China

Given the challenges facing the cyberspace of the nation, this paper presents the tripartite theory of cyberspace, based on the status quo of cyberspace. Corresponding strategies and a research architecture are proposed for common public networks （C space）, secure classified networks （S space）, and key infras- tructure networks （K space）, based on their individual characteristics. The features and security require- ments of these networks are then discussed. Taking C space as an example, we introduce the SMCRC （which stands for ＂situation awareness, monitoring and management, cooperative defense, response and recovery, and countermeasures and traceback＂） loop for constructing a cyberspace security ecosys- tem. Following a discussion on its characteristics and information exchange, our analysis focuses on the critical technologies of the SMCRC loop. To obtain more insight into national cyberspace security, special attention should be paid to global sensing and precise mapping, continuous detection and active manage- ment, cross-domain cooperation and systematic defense, autonomous response and rapid processing, and accurate traceback and countermeasure deterrence.

关键词： Cyberspace security ecosystem SMCRC loop Tripartite theory of cyberspace

Controlled fabrication and electrical-magnetic properties of Poly(OT-co-AN)/Ba_(0.8)La_(0.2)Al_2Fe_(10)O_(19) composites

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Science China(Technological Sciences) 2012年第1期55卷 6-15页

作者： CHEN KeYu xu QingQing LI LiangChao TONG GuoXiu QIAN HaiSheng xiao QiuShi xu feng Department of Chemistry Institute of Physical Chemistry Zhejiang Normal University Jinhua 321004 China

Poly（OT-co-AN）/Ba0.8La0.2Al2Fe10O19 （Poly（OT-co-AN）/BLAF） composites were fabricated by in situ polymerization method. It was investigated that of mass rate of momomer （mor/mAN）, polymeration temperature and time, and feeding ratio of BLAF effect on the structures, morphology, conductivity, magnetic property of composites by the orthogonal optimum design. The results indicated that poly （OT-co-AN） copolymer had a better coating on BLAF particles, and there were some interactions between components in the composites. The magnetic properties of the composites were related to content of the magnetic BLAF particles in it. The feeding ratio of BLAF had a significant influence on constitute and conductivity of the composites, followed by the temperature. The reflection loss and the effective bandwidth of composites for electromagnetic wave were at- tributed to the synergistic effect between poly（OT-co-AN） and BLAF. The poly（OT-co-AN）/BLAF composites with mass ratio of BLAF to mix monomer （moT^mAN =1：1） equal to 5/1 at 10 h in 25~C had a maximum synergistic effect between its compo- nents, showed a maximum reflection loss of -26.94 dB at 14.10 GHz and an available bandwidth of 8.54 GHz. It was sug- gested that the composites can be used as a advancing absorption and shielding materials for electromagnetic wave due to their favorable microwave absorption properties.

关键词： poly(OT-co-AN) copolymer Ba-ferrite conductivity magnetic property reflection loss

Austenite Grain Refinement by Reverse α′→γ Transformation in Metastable Austenitic Manganese Steel

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Journal of Iron and Steel Research International 2015年第2期22卷 157-162页

作者： Jia-tao ZHANG Yu-guang ZHAO Juan TAN xiao-feng xu Key Laboratory of Automobile Materials of Ministry of Education Department of Materials Science and EngineeringJilin University

Microstructure of metastable austenitic manganese steel after reverse transformation treatment was investi gated using optical microscopy, X ray diffraction （XRD）, electrical resistivity and hardness testing. Austenite grain refinement was successfully achieved by a two-step heat treatment. First, martensite was produced by cooling the so- lution-treated samples to --196 ℃. Then, the deep cryogenic treated samples were heated to 850 ℃ upon slow or rapid heating. The mean size of original austenite grain was about 400 fire. But the mean size of equiaxed reversion austenite was refined to 50 μm. Microstructure evolution and electrical resistivity change showed that martensite plates underwent tempering action upon slow heating, and the residual austenite was decomposed, resulting in the formation of pearlite nodules at the austenite grains boundaries. The refinement mechanism upon slow heating is the diffusion-controlled nucleation and growth of austenite. However, the reverse transformation upon rapid heating was predominated by displacive manner. The residual austenite was not decomposed. The plate α-phase was carbon-super- saturated until the starting of reverse transformation. The reverse transformation was accompanied by surface effect, resulting in the formation of plate austenite with high density dislocations. The refinement mechanism upon rapid heating is the recrystallization of displacive reversed austenite.

关键词： grain refinement displacive reverse transformation recrystallization metastable austenitic manganese steel

Galanin and its receptor system promote the repair of injured sciatic nerves in diabetic rats

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Neural Regeneration Research 2016年第9期11卷 1517-1526页

作者： xiao- feng xu Dan-dan Zhang Jin-chi Liao Li xiao Qing Wang Wei Qiu The Third Affiliated Hospital of Sun Yat-sen University Guangzhou Guangdong Province China South China Botanical Garden Chinese Academy of Sciences Guangzhou Guangdong Province China

Various studies have reported that galanin can promote axonal regeneration of dorsal root ganglion neurons in vitro and inhibit neuropathic pain. However, little is known about its effects on diabetic peripheral neuropathy, and in vivo experimental data are lacking. We hypothesized that repeated applications of exogenous galanin over an extended time frame may also repair nerve damage in diabetic peripheral neuropathy, and relieve pain in vivo. We found that neuropathic pain occurred in streptozotocin-induced diabetic rats and was more severe after sciatic nerve pinch injury at 14 and 28 days than in diabetic sham-operated rats. Treatment with exogenous galanin alleviated the neuropathic pain and promoted sciatic nerve regeneration more effectively in diabetic rats than in non-diabetic rats after sciatic nerve pinch injury. This was accompanied by changes in the levels of endogenous galanin, and its receptors galanin receptor 1 and galanin receptor 2 in the dorsal root ganglia and the spinal dorsal horn when compared with nerve pinch normal rats. Our results show that application of exogenous galanin daily for 28 days can promote the regeneration of injured sciatic nerves, and alleviate neuropathic pain in diabetic rats.

关键词： nerve regeneration peripheral nerve injury diabetes sciatic nerve galanin galanin receptor 1 galanin receptor 2 neuropathicpain dorsal root ganglion spinal dorsal horn neural regeneration

Phase diagram and transport properties of Sb-doped Ca0.88La0.12Fe2As2 single crystals

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Frontiers of physics 2017年第4期12卷 167-172页

作者： Xiang-Zhuo Xing Wei Zhou Chun-Qiang xu Nan Zhou Fei-Fei Yuan Yu-feng Zhang xiao-feng xu Zhi-Xiang Shi Department of Physics and Key Laboratory of MEMS of the Ministry of Education Southeast University Nanjing 211189 China Department of Physics and Hangzhou Key Laboratory of Quantum Matters Hangzhou Normal University Hangzhou 310036 China

The effects of isovalent Sb substitution on the superconducting properties of the Ca0.88La0.12Fe2（As1-ySby）2 system have been studied through electrical resistivity measure- ments. It is seen that the antiferromagnetic or structural transition is suppressed with Sb content, and a high-To superconducting phase, accompanied by a low-Tc phase, emerges at 0.02 ≤y ≤ 0.06. In this intermediate-doping regime, normal-state transport shows non-Fermi-liquid-like behaviors with nearly T-linear resistivity above the high-Tc phase. With further Sb doping, this high-Tc phase abruptly vanishes for y 〉 0.06 and the conventional Fermi liquid is restored, while the low-T,, phase remains robust against Sb inlpurities. The coincidence of the high-Tc phase and non-Fermi liquid transport behaviors in the intermediate Sb-doping regime suggests that AFM fluctuations play an important role in the observed non-Fermi liquid behaviors, which may be intimately related to the unusual nonbulk high-Tc phase in this system.

关键词： Sb doped Ca0.88La0.12Fe2As2 superconductors electrical resistivity measurement phase diagram

Superconductivity in kagome metal ThRu3Si2

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Chinese Physics B 2024年第5期33卷 50-55页

作者：刘艺厉静杨武璋卢佳依曹博雅李华旬柴万力武思祺李佰卓孙云蕾焦文鹤王操许晓峰任之曹光旱 School of Physics Zhejiang University Department of Applied Physics Zhejiang University of Technology School of Science Westlake Institute for Advanced Study Westlake University Department of Physics Shandong University of Technology School of Information and Electrical Engineering Zhejiang University City College Interdisciplinary Center for Quantum Information and State Key Laboratory of Silicon and Advanced Semiconductor MaterialsZhejiang University Collaborative Innovation Centre of Advanced Microstructures Nanjing University

We report the physical properties of ThRu3Si2featured with distorted Ru kagome lattice. The combined experiments of resistivity, magnetization and specific heat reveal bulk superconductivity with Tc= 3.8 K. The specific heat jump and calculated electron–phonon coupling indicate a moderate coupled BCS superconductor. In comparison with LaRu3Si2,the calculated electronic structure in ThRu3Si2shows an electron-doping effect with electron filling lifted from 100 meV below flat bands to 300 meV above it. This explains the lower superconducting transition temperature and weaker electron correlations observed in ThRu3Si2. Our work suggests the Tc and electronic correlations in the kagome superconductor could have an intimate connection with the flat bands.

关键词： superconductivity kagome lattice flat band

Three-dimensional stress variation characteristics in deep hard rock of CJPL-Ⅱ project based on in-situ monitoring

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International Journal of Mining Science and Technology 2024年第2期34卷 179-195页

作者： Minzong Zheng Shaojun Li Zejie feng Huaisheng xu Yaxun xiao State Key Laboratory of Geomechanics and Geotechnical Engineering Institute of Rock and Soil MechanicsChinese Academy of SciencesWuhan 430071China University of Chinese Academy of Sciences Beijing 100049China

In deep hard rock excavation, stress plays a pivotal role in inducing stress-controlled failure. While the impact of excavation-induced stress disturbance on rock failure and tunnel stability has undergone comprehensive examination through laboratory tests and numerical simulations, its validation through insitu stress tests remains unexplored. This study analyzes the three-dimensional stress changes in the surrounding rock at various depths, monitored during the excavation of B2 Lab in China Jinping Underground Laboratory Phase Ⅱ(CJPL-Ⅱ). The investigation delves into the three-dimensional stress variation characteristics in deep hard rock, encompassing stress components and principal stress. The results indicate changes in both the magnitude and direction of the principal stress during tunnel excavation. To quantitatively describe the degree of stress disturbance, a series of stress evaluation indexes are established based on the distances between stress tensors, including the stress disturbance index(SDI), the principal stress magnitude disturbance index(SDIm), and the principal stress direction disturbance index(SDId). The SDI indicates the greatest stress disturbance in the surrounding rock is 4.5 m from the tunnel wall in B2 Lab. SDIm shows that the principal stress magnitude disturbance peaks at2.5 m from the tunnel wall. SDId reveals that the largest change in principal stress direction does not necessarily occur near the tunnel wall but at a specific depth from it. The established relationship between SDI and the depth of the excavation damaged zone(EDZ) can serve as a criterion for determining the depth of the EDZ in deep hard rock engineering. Additionally, it provides a reference for future construction and support considerations.

关键词： Disturbance stress Tensor distance Stress disturbance index Principal stress direction Underground research laboratory