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坝基防渗墙及墙下灌浆帷幕渗流及渗透稳定性分析

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水电能源科学 2009年第2期27卷 68-70,78页

作者：余进张连明吴梦喜姜媛媛中国科学院力学研究所北京100190 中国水电顾问集团成都勘测设计研究院四川成都610072

采用三维有限元计算软件SEEPAGE1.0对扎雪水电站坝基进行了稳定渗流计算,分析了悬挂式防渗墙下灌浆帷幕深度对渗流场的影响,探讨了覆盖层中的渗透稳定性问题,确定了经济合理的防渗方案,并分析了防渗墙开裂对渗流场的影响。结果表明,覆... 详细信息

采用三维有限元计算软件SEEPAGE1.0对扎雪水电站坝基进行了稳定渗流计算,分析了悬挂式防渗墙下灌浆帷幕深度对渗流场的影响,探讨了覆盖层中的渗透稳定性问题,确定了经济合理的防渗方案,并分析了防渗墙开裂对渗流场的影响。结果表明,覆盖层中帷幕底部的渗透坡降最大,并以此处为中心,向四周迅速减小。整体渗透稳定性较好,防渗墙底部出现交错裂缝对渗控效果影响不大。

关键词：有限元深厚覆盖层悬挂式防渗墙灌浆帷幕渗透稳定性

A Quantitative Risk Assessment Approach Based on ISO 27001

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A Quantitative Risk Assessment Approach Based on ISO 27001

2011 IEEE International Conference on Information Theory and Information Security(ICITIS 2011)

作者： Yan Wei JingYi Yan Electric Power Research Institute of Guangdong Power Grid corporation Guangzhou China

A risk analysis approach formed by the combination of the qualitative and quantitative methods,which can overcome the defects of a single assessment method,is designed on the basis of introducing as well as analyzing ISO 27001 *** the specific applications,Variable Precision Rough Set （VPRS） and Analytical Hierarchy Proceed （AHP） are used to determine the index and expert weight to reduce the influence of subjective factors in some degree,group decision-making theory and fuzzy comprehensive evaluation method making the results of the assessment more accurate and more objective are used to calculate the risk ***,it verifies the correctness of the algorithm by analyzing results of the information systems,and the results conform to the facts.

关键词： ISO 27001 Analytical Hierarchy Process (AHP) Variable Precision Rough Set (VPRS) Fuzzy Comprehensive Evaluation

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石家庄省会体育中心体育场结构设计

建筑结构 2014年第23期44卷 15-19,5页

作者：王志兴顾燕宁周建锋张皓马敬友薛凯易水寒安立刚季海霞中国中建设计集团有限公司(直营总部) 北京100037 北京市建筑设计研究院有限公司北京100045

针对石家庄省会体育中心体育场结构方案,取三种计算模型进行分析比较:下部混凝土结构分缝单独计算、上部钢结构罩棚单独计算模型;下部混凝土结构分缝与上部钢结构罩棚不设缝整体计算模型;下部混凝土结构分缝与上部钢结构罩棚分缝分段整... 详细信息

针对石家庄省会体育中心体育场结构方案,取三种计算模型进行分析比较:下部混凝土结构分缝单独计算、上部钢结构罩棚单独计算模型;下部混凝土结构分缝与上部钢结构罩棚不设缝整体计算模型;下部混凝土结构分缝与上部钢结构罩棚分缝分段整体计算模型。同时考虑抗震性能化设计,针对结构构件重要程度的不同区别对待。而且体育场的平面尺寸较大,由于罩棚和看台均处于露天环境,温度应力需要引起足够重视。

关键词：体育场抗震性能化设计超长结构温度应力

Purification and Surface Modification of Fly Ash

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Purification and Surface Modification of Fly Ash

抗氧剂BHT和食品级BHT国内市场应用情况

7th World Congress on Recovery, Recycling and Re-integration

作者： Yufen Yang, Qingru Chen, Guosheng Gai, Xiangyang Hao Powder Technology R & D group, Department of Material Science and Engineering, Tsinghua University, beijing 100084, China China University of Mining Technology, Xuzhou, Jiangsu 221008, China

Purified fly ash (FA) is fit for filling in polymer because of lower density, and good dispersion and fluidity of globose particles. The reason why the use of FA as filler has not been widely generalized in polymer up to now is that interfacial bonding between FA and polymer is weak because of its slippery surface, and that FA presents grey color with about 3. whiteness-value which reduces users' interest. Although using coupling agent or surfactant to modify FA can improve in a certain degree the interfacial consistency between FA and polymer, the color and slippery surface can almost not be improved. Changes in the surface morphology and surface area of fly ash with solutions of NaOH, NaOH/NH4HCO3. EDTA, and HCI have been confirmed, however, the disposal of alkaline or acidic wastewater will be very difficult. All these restrict the wide use of FA as filler. So, in order to meet the demands of plastic and rubber industries to fillers with high qualities, to develop a new technology of fly ash surface modification and enhance their whiteness and surface area are all through our research keystone. Aiming at physical and chemical properties of fly ash, a new method of modifying fly ash and enhancing the whiteness was invented The basal characters of fly ash and preparation of composite fly ash (CFA) was described in the paper. The coating mechanism was analyzed in details. Experimental results showed that in Ca(OH)2-H2O-CO2 system composite fly ash with rough surface and high whiteness had successfully been prepared. Compared to original FA, the whiteness and the specific surface area could be increased by 145.4%, ranging from 29.8 of the original to 73.13.of CFA, and 222% from 3.03.m2/g of the original to 9.77 m2/g of CFA, respectively. Filling tests showed that the modification increased contacting opportunities between CFA and polymer and improved the matching state between them when CFA was blended with PP polymer.

关键词： fly ash, purification, modification, characteristics, polymer, filler

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石化技术 1997年第4期4卷 251-254页

作者：张翠兰北京燕山石油化工(集团)有限公司信息处

ＢＨＴ是一种用途广泛、用量较大的通用型酚类抗氧剂。近年来我国ＢＨＴ的生产能力增加的速度快，幅度大。而且，还有继续增加的潜在可能。目前国内已形成的总生产能力达２．８万ｔ左右。据预测，到２０００年，ＢＨＴ的能力将达到３．... 详细信息

ＢＨＴ是一种用途广泛、用量较大的通用型酚类抗氧剂。近年来我国ＢＨＴ的生产能力增加的速度快，幅度大。而且，还有继续增加的潜在可能。目前国内已形成的总生产能力达２．８万ｔ左右。据预测，到２０００年，ＢＨＴ的能力将达到３．３万ｔ，而市场需求量仅１．５万ｔ左右。届时，生产能力将大大超过需求，出现供大于求的局面。因此，有关部门应对ＢＨＴ今后的发展进行适量控制。

关键词： BHT 抗氧剂食品级BHT 市场应用

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强震作用下嵌岩型群桩基础的动力响应特性

筑路机械与施工机械化 2018年第4期35卷 47-53页

作者：冯忠居尹洪桦刘闯张福强马晓谦袁枫斌李孝雄吴敬武孙平宽熊英长安大学公路学院陕西西安710064 广东省交通规划设计研究院股份有限公司广东广州510000 海南省交通运输厅海南海口570000 海南省公路勘察设计院海南海口570000 中咨华科交通建设技术有限公司北京100000 滁州学院地理信息与旅游学院安徽滁州239000 中国公路工程咨询集团有限公司北京100000

结合强震区桥梁群桩基础工程,考虑桩土惯性相互作用,建立了嵌岩群桩基础三维有限元模型,分析不同加速峰值0.15g～0.60g地震波作用下嵌岩群桩基础的加速度、位移、弯矩、剪力等动力响应。研究结果表明:不同位置桩基弯矩、剪力峰值不同,... 详细信息

结合强震区桥梁群桩基础工程,考虑桩土惯性相互作用,建立了嵌岩群桩基础三维有限元模型,分析不同加速峰值0.15g～0.60g地震波作用下嵌岩群桩基础的加速度、位移、弯矩、剪力等动力响应。研究结果表明:不同位置桩基弯矩、剪力峰值不同,边桩和中桩较大,角桩较小;弯矩峰值普遍出现在基岩面附近,剪力峰值普遍出现在桩顶和基岩面附近,研究成果为类似嵌岩群桩基础的科学设计提供了理论依据。

关键词：强震区大直径嵌岩群桩基础动力响应

An Analysis of the Realty Leasing Market in Qianmen and Zhongguancun Areas of beijing

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China City Planning Review 1992年第2期9卷 42-55页

作者： The Research group on the Use and Management of the Urban Land in China Zhang Lizhen

The urban realty market is very complicated with wide-ranging contents and manyproblems. in the past, we focused our research mainly on the land auction, land rental inbatches, public bidding and the development of mass plots of land in the coastal open cit-ies, while neglecting the research on the real estate leasing and structural readjustment ofurban land use and housing Therefore. we have selected two typical areas in beijing foron-the -spot investigation. One is Qianmen ——the most prosperous area in beijingwith all kinds of big, medium-sized and small enterprises of public, collective and privateownership, and with brisk commercial activities and busy real estate leasing business. Theother area is the Zhongguancun ——the key section of the experimental area in beijing forthe development of new technology and{3.. In the past few years there have set upnew and high-tech enterprise groups with multiple subjects, Various categories and acombination of technology, industry and trade, which represent the direction for the de-velopment of science, technology and new productivity. Along with the mass explosivedevelopment of a large number of companies, the structure of the land use in that area haschanged dramatically. the leasing and transaction of the real estate are very active the re,and the rents and prices of land and housing have come up to the highest in beijing.

关键词： An Analysis of the Realty Leasing Market in Qianmen and Zhongguancun Areas of beijing

一种Ti-6Al-2Zr-1Mo-1V合金锻件的宏观与微观组织特征分析

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钛工业进展 2004年第2期21卷 23-26页

作者：曹京霞黄旭孙贵东方波北京航空材料研究院北京100095 沈阳黎明航空发动机集团公司辽宁沈阳110043

研究了Ti-6Al-2Zr-1Mo-1V合金环锻件的宏观和微观组织,分析了锻件的变形和热处理工艺。对Ti-6Al-2Zr-1Mo-1V合金环锻件采用了β→α+β温度区域的热变形工艺,即在β区温度下开始变形,α+β区温度下结束变形,锻件的退火温度略低于β相的... 详细信息

研究了Ti-6Al-2Zr-1Mo-1V合金环锻件的宏观和微观组织,分析了锻件的变形和热处理工艺。对Ti-6Al-2Zr-1Mo-1V合金环锻件采用了β→α+β温度区域的热变形工艺,即在β区温度下开始变形,α+β区温度下结束变形,锻件的退火温度略低于β相的临界分解温度T_K;采用β→α+β温度区域热变形的锻件具有中等强度水平,良好的室温冲击性能和高温蠕变、持久性能;β→α+β温度区域的变形工艺具有简化变形工序、降低变形抗力的优点,但变形时间的控制较难掌握,需一定的实践探索。

关键词： Ti-6Al-2Zr-1Mo-1V合金锻件钛合金微观组织宏观组织热加工退火

彩色多普勒超声对老年高血压患者颈动脉、椎动脉血流参数测定分析

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实用老年医学 1998年第2期12卷 65-67页

作者：戈晓华邹艳秋赵红中国铁道建筑总公司总医院

目的用彩色多普勒超声观察老年高血压患者颈动脉、椎动脉结构和血流动力学变化。方法应用彩色多普勒超声仪，５．０～７．５ＭＨｚ探头，检测１１２例老年高血压患者双侧颈总动脉（ＣＣＡ）、颈内动脉（ＩＣＡ）、椎动脉（ＶＡ）粥样硬... 详细信息

目的用彩色多普勒超声观察老年高血压患者颈动脉、椎动脉结构和血流动力学变化。方法应用彩色多普勒超声仪，５．０～７．５ＭＨｚ探头，检测１１２例老年高血压患者双侧颈总动脉（ＣＣＡ）、颈内动脉（ＩＣＡ）、椎动脉（ＶＡ）粥样硬化斑块发生情况。血流参数：收缩期峰值流速（ＳＰＶ）、舒张末期流速（ＥＤＶ）、平均流速ＴＡＭＸ、搏动指数（ＰＩ）和阻力指数（ＲＩ）变化，并与２５９名健康老人进行对照分析。结果①高血压组斑块检出率为９２．８％，健康组斑块检出率为２２．８％，２组差异非常显著（Ｐ＜０．０１）。②高血压组ＳＰＶ、ＥＤＶ、ＴＡＭＸ较健康组明显减慢（Ｐ＜０．０５，Ｐ＜０．０１）ＰＩ和ＲＩ明显高于健康组（Ｐ＜０．０１）。③病例组多普勒频谱多有形态改变。结论老年高血压患者颈动脉硬化多较显著，血流动力学改变以流速减慢，外周阻力增大为主。

关键词：彩色多普勒高血压颈动脉粥样硬化血流参数