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数字生活 2003年第9期 6-86页

作者：汪利亚

来zone就像到了世外桃源,坐在屋子里只有音乐声。音乐停止,一切静得出奇。也许是在后海的深处,这里只有匆匆过往的车、人。有一片广阔的海域,到了晚上还有广阔的海域,到了晚上还有前海连成串、穿成线、构成景的灯光。

关键词：后海 zone 沙发

Characterization of focusing performance of spiral zone plates with fractal structure

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Chinese Physics B 2019年第6期28卷 184-188页

作者： Hua-Ping Zang Cheng-Long Zheng Zi-Wen Ji Quan-Ping Fan Lai Wei Yong-Jie Li Kai-Jun Mu Shu Chen Chuan-Ke Wang Xiao-Li Zhu Chang-Qing Xie Lei-Feng Cao Er-Jun Liang School of Physics Science and Engineering Zhengzhou UniversityZhengzhou 450001China National Key Laboratory for Laser Fusion Research Center of Laser FusionChina Academy of Engineering PhysicsMianyang 621900China Information and Telecommunication Company of State Grid Henan Electric Power Corporation Zhengzhou 450001China Key Laboratory of Nano-Fabrication and Novel Devices Integrated Technology Institute of MicroelectronicsChinese Academy of SciencesBeijing 100029China

We propose an efficient method of generating a vortex beam with multi-foci by using a fractal spiral zone plate(FSZP), which is designed by combining fractal structure with a spiral zone plate(SZP) in the squared radial *** theoretical analysis reveals that the number of foci that embed vortices is significantly increased as compared with that obtained by using a conventional SZP. Furthermore, the influence of topological charge on the intensity distribution in focal plane is also discussed in detail. For experimental investigation, an FSZP with topological charge p = 1 and 6.4 mm diameter is fabricated by using a photo-etching technique. The calibration indicates that the focusing performances of such a kind of zone plane(ZP) accord well with simulations, thereby providing its potential applications in multi-dimensional optical manipulation and optical imaging technology.

关键词： optical vortices spiral zone plate diffractive optical elements

Structure-property relationships in heat-affected zone of gas-shielded arc-welded V-N microalloyed steel

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Journal of Iron and Steel Research International 2018年第12期25卷 1244-1254页

作者： Jun Hu Lin-xiu Du Bin Zhang Xiang-yu Qi Xiu-hua Gao R.D.K.Misra The State Key Laboratory of Rolling and Automation Northeastern UniversityShenyang 110819LiaoningChina Laboratory for Excellence in Advanced Steel Research Department of MetallurgicalMaterials and Biomedical EngineeringUniversity of Texas at El PasoEl Paso TX 79968-0521USA

The structure-property relationship in heat-affected zone (HAZ)of a low-carbon steel bearing V-N subjected to gasshielded arc welding was *** microstructural characteristics of base metal (BM),coarse-grained HAZ (CGHAZ),fine-grained HAZ,and intercritical HAZ were significantly *** effect of grain-refinement strengthening and transformation hardening on HAZ contributed to equivalent hardness of 260.8-278.5 HV in comparison with BM hardness of 272.0 ***,excellent impact toughness at -20 ℃ was obtained because of high resistance to crack propagation by high-misorientation boundaries,leading to impact fracture consisting of *** CGHAZ,free N was partly fixed by V(C,N)precipitates,such that the deterioration effect of N on toughness was considered to be nearly *** comparison with CGHAZ,weld metal contained higher fraction of acicular ferrite with fine plates,while the impact toughness was inferior because of the detrimental influence of coarse inclusions from the welding *** nanoscale V(C,N)precipitates in CGHAZ had weak effect on toughness because of small size.

关键词： V-N microalloying Heat-affected zone Acicular ferrite Hardness Toughness Gas-shielded arc welding V-N microalloyed steel

Effect of heat input on austenite microstructural evolution of simulated heat affected zone in 2205 duplex stainless steel

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Journal of Iron and Steel Research International 2019年第5期26卷 435-441页

作者： Tian-hai Wu Jian-jun Wang Hua-bing Li Zhou-hua Jiang Chun-ming Liu Hong-yang Zhang Key Laboratory for Anisotropy and Texture of Materials Ministry of Education Northeastern University Shenyang 110819 Liaoning China School of Materials Science and Engineering Northeastern University Shenyang 110819 Liaoning China School of Metallurgy Northeastern University Shenyang 110819 Liaoning China Shenyang Northeastern Institute of Metal Materials Co. Ltd. Shenyang 110108 Liaoning China

The effect of simulated welding thermal cycle on the microstructure and impact toughness of heat affected zone (HAZ) in 2205 duplex stainless steel was investigated by optical microscopy, scanning electron microscopy, transmission electron microscopy and room temperature impact test. The results show that the morphology and volume fraction of austenite change greatly with heat input. The amount of residual austenite and grain boundary austenite (GBA) decreases while Widmanstatten austenite (WA) laths and intergranular austenite increase with the increase in heat input. Only the fine equiaxed austenite exists in the HAZ when the heat input is increased up to 61.8 kJ/cm. WA laths nucleate initially either at the ferrite and GBA phase boundaries or directly in ferrite grains and begin to decompose into diamond-shaped austenite with the heat input larger than 25.2 kJ/cm. The impact toughness shows a non-monotonic variation, which is related to the increase in austenite fraction and the formation and the decomposition of WA laths.

关键词： 2205 duplex stainless steel Simulated heat affected zone Heat input Widmanstatten austenite Impact toughness

The characteristics of the structure, strain and kinematic vorticity of the Wulian detachment fault zone, Shandong Peninsula, China

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Science China Earth Sciences 2019年第9期62卷 1399-1415页

作者： Jinlong NI Junlai LIU Yujie SUN Xiaoxiao SHI Shen LI Shandong Provincial Key Laboratory of Depositional Mineralization and Sedimentary Minerals College of Earth Sciences and Engineering Shandong University of Science and Technology Qingdao 266590 China State Key Laboratory of Geological Processes and Mineral Resources China University of Geosciences Beijing 100083 China Laboratory for Marine Mineral Resources Qingdao National Laboratory for Marine Science and Technology Qingdao 266071 China Cores and Samples Center of Land & Resources China Geological Survey Langfang 065200 China

As one of the vital tectonic units of the Wulian Metamorphic Core Complex(MCC), the Wulian detachment fault zone(WDFZ), which developed in the Jiaodong peninsula, separates the lower plate of the ultrahigh pressure(UHP) metamorphic rocks in the Sulu orogenic belt from the upper plate of the early Cretaceous Zhucheng basin and the basin basement. The fault zone generally strikes NNE with a dip in the west along the southern portion of the MCC and strikes NE with a dip in the WNWalong the northern portion. The fault zone displays a wavy-tile-shaped extension on the plane, principally composed of the fault breccias and mylonite and transits downward to the mylonitic gneiss. As a whole, the detachment fault zone shows a top-towest or a WNW extension. By calculating the harmonic mean, we obtain a Flynn index K of 0.98–2.0, and the mean value is approximately 1.35 in the fault zone. According to the polar Mohr construction, the extensional crenulation cleavage, the RS/θ,and the quartz C-axial fabric methods, we acquire mean kinematic vorticity values of 0.64–0.97, 0.76–0.93, 0.6–0.92, and 0.63–0.98 with mean values of 0.83, 0.80, 0.78 and 0.86, respectively, for mylonite and promylonite. The strain measurement results and the kinematic vorticity values indicate that the WDFZ is a normal ductile shear zone developed in the extensional *** kinematic track shows that the kinematic vorticity value decreases gradually from the NW to the SE as a whole. A simple shear dominates in the middle and upper parts of the shear zone, which is reflected by a higher vorticity value(>0.75, up to 0.98),a low thinning rate and a lower K value. In contrast, toward the footwall, the pure shear is increased significantly, showing a lower vorticity value(<0.70, low to 0.64), a relatively high thinning rate and a higher K value. Combined with the geotectonic background, the development and evolution of the WDFZ should respond to lithospheric thinning and the destruction of the North China

关键词： Wulian Strain intensity Kinematic vorticity Mylonite Detachment fault zone

Model of the Crustal Magnetic Field in the Martian Aurora zone

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Chinese Physics Letters 2011年第11期28卷 286-288页

作者： TONG Dong-Sheng CHEN Chu-Xin School of Earth and Space Sciences University of Science and Technology of ChinaHefei 230026

It is well known that aurorae are prominent on planets with a global magnetic field and occur where open magnetic field lines *** UV spectrometer used for investigating the characteristics of the atmosphere of Mars(SPICAM)on board the Mars Express made the first observation of auroral-type emission in the cusp region of the strong crustal magnetic field on Mars and found that the arc of the Martian aurora zone is very narrow in width,which obviously differs from that of other *** on the observation,we put forward a model of a crustal magnetic field on the Martian aurora zone through the morphology of Martian *** the model,equivalent currents are proposed;the topology and magnitude of the magnetic field generated by these equivalent currents are consistent with that of the crustal magnetic field in the Martian aurora *** morphology of the Martian aurora zone generated through the model matches well with the observations made by the Mars Express orbiter.

关键词： zone crustal currents

Mantle transition zone structure beneath the Central Asian Orogenic Belt

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Science China Earth Sciences 2020年第4期63卷 548-560页

作者： Jing HE Qingju WU Key Laboratory of Crustal Dynamics Institute of Crustal DynamicsChina Earthquake AdministrationBeijing 100085China Key Laboratory of Seismic Observation and Geophysical Imaging Institute of GeophysicsChina Earthquake AdministrationBeijing 100081China

Over the past decades, there have been hot debates in the geodynamic community regarding to the deep evolution mechanisms of Cenozoic volcanism in the Central Asian Orogenic Belt(CAOB). Of all the constraints available, high resolution structure of upper mantle discontinuities, especially the discontinuities at depths of 410 km(D410) and 660 km(D660), is of the most important, which may provide reliable clues on the magma channel as well as its evolution. In this work, we adopt the common conversion point stacking technique with teleseismic radial P-wave receiver functions to examine the D410 and D660 discontinuities. The primary results exhibit that the major characteristics of the mantle transition zone(MTZ) obtained by different velocity models are largely consistent. Obviously elevated D410 and slightly depressed D660 are observed beneath the Hannuoba Volcano, suggesting possible delamination of the local lithosphere deposited at the D410. This process may induce upwelling of the asthenospheric materials filling the space left by the delaminated lithosphere, and subsequently trigger volcanic eruptions. Strong depressions are observed at both D410 and D660 depths beneath west of the Dariganga Volcano, and the depression of D660 is more pronounced. It leads to the apparently thickened MTZ, indicating the presence of cold material at the D660. This cold material is speculated as a stagnant slab from the subducted Pacific Plate or the remains of a detached island arc system from the collision and formation of the CAOB. Slightly thinner MTZ is found beneath the Hentey Mountains and the Middle Gobi Volcano. Apparently, this thinner MTZ is not significant enough to support the existence of high thermal anomalies,which may rule out the possibility of large-scale hot material upwelling from either the local MTZ or even the lower mantle.

关键词： Central Asian Orogenic Belt Cenozoic Volcano Mantle transition zone Receiver function

Mechanical mechanism of overlying strata breaking and development of fractured zone during close-distance coal seam group mining

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International Journal of Mining Science and Technology 2020年第2期30卷 207-215页

作者： Jianguo Ning Jun Wang Yunliang Tan Qiang Xu College of Mining and Safety Engineering State Key Laboratory Breeding Base for Mining Disaster Prevention and ControlShandong University of Science and TechnologyQingdao 266590China

This study mainly investigates the mechanical mechanism of overlying strata breaking and the development of fractured zones during close-distance coal seam group mining in the Gaojialiang coal ***,a mechanical model for the second"activation"of broken overlying strata is established,and the related mechanical"activation"conditions are obtained.A recursive formula for calculating the separation distance of overlying strata is ***,a height determining method for predicting the height of fractured zones during close-distance coal seam group mining is proposed based on two values,namely,the separation distance and ultimate subsidence value of overlying *** method is applied to calculate the fractured zone heights in nos.20107 and 20307 mining *** calculated results are almost equal to the field observation ***,a modified formula for calculating the height of a waterflowing fractured zone is proposed.A comparison of the calculated and observed results shows that the errors are *** height determining method and modified formula not only build a theoretical foundation for water conservation mining at the Gaojialiang coal mine,but also provide a reference for estimating the height of water-flowing fractured zones in other coal mines with similar conditions.

关键词： Coal seam group Activation mechanism Separation Water-flowing fractured zone Modified formula

Correlation between microstructure and impact toughness of weld heat-affected zone in 5 wt.% manganese steels

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Journal of Iron and Steel Research International 2019年第7期26卷 761-770页

作者： Jun-hui Li Hong-hong Wang Qiang Luo Li Li Chao Sun R.D.K. Misra The State Key Laboratory of Refractories and Metallurgy Wuhan University of Science and Technology Wuhan 430081 Hubei China Research Institute of Nanjing Iron and Steel Co. Ltd. Nanjing 210035 Jiangsu China Laboratory for Excellence in Advanced Steel Research Department of Metallurgical Materials and Biomedical Engineering University of Texas at El Paso El Paso TX 7996& USA

The microstructure in welding heat-affected zones of 5 wt.% manganese steels was studied, and its effect on impact toughness was analyzed. The simulated coarse-grained heat-affected zone (CGHAZ) had the lowest impact toughness of ~39 J at — 40℃ because of coarse-grained structure and least volume fraction of retained austenite (RA) of 1.2 vol.%. The impact toughness of simulated intercritical heat-affected zone (ICHAZ) and fine-grained heat-affected zone (FGHAZ) were ~165 and ~45 J, respectively, at — 40℃. The effective grain size of simulated FGHAZ was smaller than that of the simulated ICHAZ. Furthermore, microstructural investigation revealed that the simulated FGHAZ and ICHAZ had similarity in volume fraction and stability of RA. However, tempered martensite was present in ICHAZ and absent in FGHAZ. It is proposed that the presence of tempered martensite contributed to good impact toughness in simulated ICHAZ.

关键词： 5 wt.% manganese steel Welding heat-affected zone Retained austenite Tempered martensite Impact toughness

Nanofabrication of 50 nm zone plates through e-beam lithography with local proximity effect correction for x-ray imaging

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Chinese Physics B 2020年第4期29卷 456-461页

作者： Jingyuan Zhu Sichao Zhang Shanshan Xie Chen Xu Lijuan Zhang Xulei Tao Yuqi Ren Yudan Wang Biao Deng Renzhong Tai Yifang Chen Nanolithography and Application Research Group State Key Laboratory of Asic and SystemSchool of Information Science and EngineeringFudan UniversityShanghai 200433China Shanghai Synchrotron Radiation Facility Shanghai Institute of Applied PhysicsChinese Academy of SciencesShanghai 201204China

High resolution Fresnel zone plates for nanoscale three-dimensional imaging of materials by both soft and hard x-rays are increasingly needed by the broad applications in nanoscience and *** the outmost zone-width is shrinking down to 50 nm or even below,patterning the zone plates with high aspect ratio by electron beam lithography still remains a challenge because of the proximity *** uneven charge distribution in the exposed resist is still frequently observed even after standard proximity effect correction(PEC),because of the large variety in the line *** work develops a new strategy,nicknamed as local proximity effect correction(LPEC),efficiently modifying the deposited energy over the whole zone plate on the top of proximity effect *** this way,50 nm zone plates with the aspect ratio from 4:1 up to 15:1 and the duty cycle close to 0.5 have been *** imaging capability in soft(1.3 keV)and hard(9 keV)x-ray,respectively,has been demonstrated in Shanghai Synchrotron Radiation Facility(SSRF)with the resolution of 50 *** local proximity effect correction developed in this work should also be generally significant for the generation of zone plates with high resolutions beyond 50 nm.

关键词： Fresnel zone plates electron beam lithography local proximity effect correction x-ray imaging 50 nm resolution