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Experimental Study on the Effect of Cyclic Preloading on the Resistance to Liquefaction of Saturated Loose Sand under Wave Loading

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Journal of Shanghai Jiaotong university(science) 2009年第4期14卷 398-403页

作者：张振东栾茂田金丹郭莹聂影 State Key Laboratory of Coastal and Offshore Engineering Dalian University of Technology institute of Geotechnical Engineering School of Civil and Hydraulic EngineeringDalian University of Technology Department of Civil Engineering Huaihai Institute of Technology

By using the soil static and dynamic universal triaxial and torsional shear apparatus, a series of combined cyclic shear tests are performed to simulate the rotation in the principal stress direction induced by ocean wave. The tests include the cyclic preloading tests and liquefaction tests in the second loading on saturated loose sand with a relative density of 30%. The all tests are consolidated under isotropic condition. The effect of the cyclic preloading on the resistance to liquefaction of saturated loose sands under the condition of continuous rotation in the principal stress direction is investigated. Experimental data indicate that the void ratio of saturated sands has a negligible reduction after cyclic preloading. With the increase of the intensity of cyclic preloading (in the amplitude and in the number of cycles), the resistance to liquefaction in the second loading is increased continuously under the condition that the liquefaction does not occur during the cyclic preloading. The reason is that the construction of more stable structure due to the uniformity of the void and the better interlocking of the particles when the cyclic preloading is applied to the saturated sand.

关键词： saturated sand liquefaction continuous rotation in the principal stress direction cyclic preloading second loading void ratio

A NOTE ON OPTIMALITY CONDITIONS IN MULTIOBJECTIVE PROGRAMMING

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Systems science and Mathematical sciences 1988年第2期 184-190页

作者：汪寿阳 institute of Systems science Academia Sinica Beijing china

In this paper we discuss necessary conditions in multiobjective *** first give a counterexample to [1,Theorem 2.1] and then present its correctform with which we can easily establish the generalized Kuhn-Tucker necessary ***-Tucker type of necessary condition is given,but the proof goes in another line which canexpose something essential to multiobjective *** remarks are also given,including two interesting problems.

关键词： Th A NOTE ON OPTIMALITY CONDITIONS IN MULTIOBJECTIVE PROGRAMMING

Tectonic evolution of the Dabieshan orogen: In the view from polyphase deformation of the Beihuaiyang metamorphic zone

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science china Earth sciences 2005年第7期48卷 886-899页

作者： LIN Wei1, 2, Faure Michel3, WANG Qingchen1 & Arnaud Nicolas4 1. LTE, institute of Geology and Geophysics, Chinese Academy of sciences, Beijing 100029, china 2. Department of Earth and Planetary sciences, Graduate School of science, Nagoya University, Japan 3. ISTO, UMR CNRS 6113, Batiment Géosciences, Orléans Université d’Orléans, 45067 Orléans Cedex 2, France 4. UMR 6524 "Magmas et Volcans", 5 Rue Kessler, 63000 Clermont-Ferrand, France LTE Institute of Geology and Geophysics Chinese Academy of Sciences Beijing 100029 China Department of Earth and Planetary sciences Graduate School of Science Nagoya University Japan ISTO UMR CNRS 6113 Orléans Université d'Orléans 45067 Orléans Cedex 2 France UMR 6524 Magmas et Volcans 63000 Clermont-Ferrand 5 Rue Kessler France

The Beihuaiyang metamorphic zone was formed by the Early Mesozoic collision of the North and South china Blocks. It consisted of the Foziling and Luzhenguan complexes and was thought to have never afforded a deep subduction. A similar feature of the deformation in the Dabieshan UHP metamorphic rocks implies that these different tectonic units share the same geodynamic background. The early stage of deformation can be preserved on account of their relatively shallower subduction than that for UHP rocks. On the basis of an analysis of the geo- logical structure and geochronological results, five deformational stages have been recognized: a D1-Early compressional deformation which represents the continental subduction; a D2-Early exhumation deformation producing a syn-convergence exhumation; a D3-Main deformation, represented by an exhumation deformation with Late Triassic age; a D4-Doming and its margin extensional gravity collapse deformation and finally a D5-regional extensional deformation of Cretaceous that was mostly introduced by the migmatization and plutonism.

关键词： Beihuaiyang metamorphic zone geometry kinematic polyphase deformation tectonic evolution.

Morphologies of Fe-66.7 at.%Si alloy solidified in a drop tube

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science china(Physics,Mechanics & Astronomy) 2005年第6期48卷 658-666页

作者： WANG Haiyan1,2, LIU Riping1, MA Mingzhen1, JING Qin1, LI Gong1, SUN Liling2 & WANG Wenkui1,2 1. Key Laboratory of Metastable Materials science & Technology, Yanshan University, Qinhuangdao 066004, china 2. institute of Physics, Chinese Academy of sciences, Beijing 100080, china 1. Key Laboratory of Metastable Materials science & Technology Yanshan University 066004 Qinhuangdao China 2. institute of Physics Chinese Academy of Sciences 100080 Beijing China

Solidification of 0.1―1.0 mm diameter droplets of Fe-66.7 at.%Si alloy was achieved in a 3 m drop tube. The XRD, EDS, and SEM measurements reveal that all the droplets are composed of the primary phase α and the α+ε eutectic. With decreasing droplet diameter, the growth mode of the primary phase α changes from faceted to nonfaceted growth and the eutectic changes from needle-like to anomalous eutectic. In addition, the width of the primary phase α decreases with decreasing droplet size. The different cooling rates and undercooling levels corresponding to the samples with different sizes are responsible for the morphology changes. The cooling rates of the samples with different diameters during free fall were calculated and their effects on the microstructure formation were discussed. This kind of transition is also found inside the same sample, which is due to the larger cooling rate on the surface than at the center.

关键词： Fe-Si alloy, solidification, drop tube, undercooling.

Lead Isotopic Steep-Dipping Zone and　Mineralization—An Example from　Mineral Deposits Concentrated　Area in East Qinling,china

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Journal of Earth science 2000年第1期19卷 68-75页

作者： Zhang Zhengwei Zhu Bingquan Guangzhou institute of Geochemistry, china Academy of science, Guangzhou 510640 Cai Keqin Deng Jun Department of Earth and Mineral Resources, china University of Geosciences, Beijing 100083 Wang Wei Qiang Lizhi Henan

Lead isotopic geochemical steep-dipping zone usually exists on inhomogeneous boundaries of earth blocks. Its crossing with the geophysical gradient zone often convergently occurs at giant deposits. Deep structures or concealed structural planes obviously have the coupling relationship with the convergent area of mineral deposits. The geochemical steep-dipping zone is usually distributed along the boundary of ancient continental blocks. Its crossing effect with geophysical gradient zone is usually presented as depression or swell of Moho discontinuity on the crossing direction with the ancient continental margin, which would lead to form deep fractures of earth crust at block margins or lead to adjustment of earth crust texture. The deep hydrothermal liquid would rise up along the structural planes to form the convergent areas of mineral deposits. For example, Luonan- Luanchuan area in east Qinling is a typical crossed area of the geochemical steepdipping zone and geophysical gradient zone. The mineral deposit belt extends along EW direction. It was controlled by the geochemical steepdipping zone equidistantly distributed along NE direction like a string of beads controlled by a gravity gradient zone in NE direction and a mantle depression slope. Along a plunging mantle syncline on EW plunging direction, from the east to the west, checkform was distributed which controls synergic crustmantle granoporphyry rocks. Therefore, a convergent mineralization area of Mo, W, Zn and Au giant deposits occurred.

关键词： lead isotopic steep-dipping zone mineralization East Qinling.

Effect of 5'-deletion of Arabi-dopsis profilin2 promoter on its vascular specific expression

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Chinese science Bulletin 2001年第19期46卷 1627-1630页

作者： LIU Yuhui, WANG Zhixing & JIA ShirongBiotechnology Research institute, Chinese Academy of Agricultural sciences, Beijing 100081, china Biotechnology Research institute Chinese Academy of Agricultural Sciences Beijing China

Based on the published sequence of profilin2 promoter of Arabidopsis thaliana, a full-length promoter (1667 bp) was amplified by PCR. The 5’ -end deletion fragments with length of 1380, 1153, 969 and 597 bp were then fused with gus (uid\) gene respectively. Constructed plant expression vectors were individually transferred into Kalan-choe laciniata and transgenic plants regenerated. GUS his-tochemical assay confirmed that the full-length promoter Pfnl.7 was vascular-specific. Deletion assays showed that profilin2 promoter could be divided into three parts. Deletion of fragment 1 ( -1667 -1380 bp) resulted in constitutive expression, suggesting that element(s) responsible for vascular-specific expression might exist in this region. Fragment 2 located at -1153 - -597 bp strongly inhibited gus gene expression. Fragment 3 ( -597 - -1 bp) is considered as a basic domain of profilin2.

关键词： profilin2 promoter Kalanchoe constitutive expression vascular-specific expression.

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社会印象:意识,还是无意识控制

心理科学 2000年第4期23卷 440-445页

作者：周爱保西北师范大学教育科学研究院心理研究室!兰州 730070

通过两个实验分别考察了在自然判断和社会判断条件下社会印象受意识控制情况的不同特点。实验—采用 2× 2× 2× 2的混合设计 ,给被试提供不同声望、不同性别的人名 (组内设计 ) ,考察了在再认判断和频度判断条件下 (组内设计 )被试性... 详细信息

通过两个实验分别考察了在自然判断和社会判断条件下社会印象受意识控制情况的不同特点。实验—采用 2× 2× 2× 2的混合设计 ,给被试提供不同声望、不同性别的人名 (组内设计 ) ,考察了在再认判断和频度判断条件下 (组内设计 )被试性别特征 (组间设计 )对社会记忆的影响 ;实验二采用 2× 2× 2× 2的混合设计 ,给被试呈现不同性别的人名 (组内设计 ) ,考察了新、旧人名 (呈现与否 ,组内设计 )在声望判断和影响力判断条件下 (组内设计 ) ,被试性别特征 (组间设计 )对社会印象影响 ;同时 ,还探讨了信号检测论 (SDT)方法对测量内隐社会印象的有效性。结果表明 ,在自然判断的任务条件下 ,被试的记忆出现了“名人优势效应” ;在社会判断的任务条件下 ,被试的辨别力非参数指标A′没有表现出显著的差异 ,而其判断标准 β则在被试性别、判断类型上表现出了差异。

关键词：判断任务社会记忆内隐社会印象辨别力指数A’ 判断标准β

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垃圾焚烧飞灰理化特性研究

燃料化学学报 2004年第2期32卷 175-179页

作者：李润东聂永丰李爱民王雷严建华岑可法沈阳航空工业学院清洁能源与环境工程研究所辽宁沈阳110034 清华大学环境科学与工程系北京100084 浙江大学热能工程研究所浙江杭州310027

应用能谱分析、灰熔点炉、XRD、压汞仪等仪器手段对国内外8种垃圾焚烧飞灰的成分、熔点、晶相结构、颗粒特性等物理化学性质进行了系统研究。研究表明,飞灰成分因为受原料、炉型、取样位置等因素影响而差异很大。由于飞灰的成分差异导... 详细信息

应用能谱分析、灰熔点炉、XRD、压汞仪等仪器手段对国内外8种垃圾焚烧飞灰的成分、熔点、晶相结构、颗粒特性等物理化学性质进行了系统研究。研究表明,飞灰成分因为受原料、炉型、取样位置等因素影响而差异很大。由于飞灰的成分差异导致垃圾焚烧飞灰比煤灰更易于熔融,对熔融处理有利,这主要归因于飞灰中SiO2含量以及SiO2 Al2O3差异,熔点与SiO2含量存在正比关系;添加CaO实现助熔是有条件的,不同飞灰由于焚烧条件和飞灰成分不同导致晶相组成有一定差异;飞灰内部孔径主要分布于0.3μm～1.5μm范围内,飞灰的比表面积为20.5m2 g。

关键词：垃圾焚烧飞灰理化特性

Geochemistry and mineralogy of the Late Permian coals from the Songzao Coalfield, Chongqing, southwestern china

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science china Earth sciences 2007年第5期50卷 678-688页

作者： DAI ShiFeng1,2, ZHOU YiPing3, REN DeYi1, WANG XiBo1, 2, LI Dan1, 2 & ZHAO Lei1, 2 1 State Key Laboratory of Coal Resources and Safe Mining (china University of Mining and Technology), Beijing 100083, china 2 Department of Resources and Earth science, china University of Mining and Technology, Beijing 100083, china 3 Kunming Research institute of Coal science, Kunming 650041, china State Key Laboratory of Coal Resources and Safe Mining (china University of Mining and Technology) Beijing 100083 China Department of Resources and Earth science China University of Mining and Technology Beijing 100083 China Kunming Research institute of Coal science Kunming 650041 China State Key Laboratory of Coal Resources and Safe Mining (china University of Mining and Technology) Beijing 100083 China

Mineralogy and geochemistry of the four main workable coal seams (No.6, No.7, No.8, and No.11) of Late Permian age from the Songzao Coalfield, Chongqing, Southwest china, were examined using in- ductively coupled plasma-mass spectrometry (ICP-MS), X-ray fluorescence spectrometry (XRF), cold-vapor absorption spectrometry (CV-AAS), ion-selective electrode (ISE), scanning electron mi- croscopy equipped with an energy-dispersive X-ray spectrometer (SEM-EDX), and X-ray diffraction analysis (XRD). The results showed that the main workable No.8 Coal that accounts for about 60% of the total coal reserves in the Songzao Coalfield was not enriched in hazardous trace elements. The No.11 Coal has high concentrations of alkaline elements, Be (9.14 μg/g), Sc (12.9 μg/g), Ti (9508 μg/g), Mn (397 μg/g), Co (23.7 μg/g), Cu (108 μg/g), Zn (123 μg/g), Ga (32 μg/g), Zr (1304 μg/g), Nb (169 μg/g), Hf (32.7 μg/g), Ta (11.4 μg/g), W (24.8 μg/g), Hg (0.28 μg/g), Pb (28.1 μg/g), Th (24.1 μg/g), and rare earth elements (509.62 μg/g). The concentration of Nb and Ta in the No. 11 Coal is higher than the industrial grade, and their potential utilization should be further studied. Besides pyrite, quartz, calcite, and clay minerals, trace minerals including chalcopyrite, marcasite, siderite, albite, mixed-layer clay minerals of illite and smectite, monazite, apatite, anatase, chlorite, and gypsum were found in the No.11 Coal. It should be noted that alabandite of hydrothermal origin and anatase occurring as cement were identi- fied in coal. In addition, the clayey microbands derived from alkaline volcanic ashes were identified in the coal. The dominant compositions of these clayey microbands were mixed-layer clay minerals of illite and smectite, which were interlayered with organic bands. The modes of occurrence of alkaline volcanic ash bands indicate that the volcanic activities were characterized by the multiple eruptions, short time interval and small scale for each eruption during peat accumu

关键词： coal trace elements mineral alkaline volcanic ash Late Permian period Songzao Coalfield