oalib
Search Results: 1 - 10 of 100 matches for " "
All listed articles are free for downloading (OA Articles)
Page 1 /100
Display every page Item
凝胶注模堇青石-莫来石复相材料的制备及其抗热震性能  [PDF]
杨现锋,李 勇,徐协文,蔡 星,谢志鹏
硅酸盐学报 , 2014, DOI: 10.7521/j.issn.0454-5648.2014.09.16
Abstract: 采用凝胶注模方法制备堇青石-莫来石复相材料,研究了聚乙烯醇对浆料稳定性、固化时间和表面氧阻聚的影响,分析了堇青石-莫来石复相材料的抗热震性能。结果表明,聚乙烯醇可提高粗颗粒悬浮体系的稳定性,增大浆料黏度,延长固化时间。聚乙烯醇还可以起到消除表面起皮、开裂的作用。通过控制浆料固相含量调节堇青石-莫来石复相材料的气孔分布,从而影响其热震稳定性。当浆料中堇青石-莫来石固相体积分数为41%~44%时,堇青石-莫来石复相材料的热震稳定性最好。
可加工BN/B_4C复相陶瓷的制备与其抗热震性能  [PDF]
江涛,金志浩,乔冠军,杨建锋
硅酸盐学报 , 2010,
Abstract: 采用热压烧结工艺制备了BN/B4C微米复相陶瓷和BN/B4C纳米复相陶瓷。由淬水法测试了单相B4C陶瓷,BN/B4C微米复相陶瓷和BN/B4C纳米复相陶瓷的抗热震性能,用三点弯曲法测试了热震后样品的抗弯强度。结果表明BN/B4C微米复相陶瓷和BN/B4C纳米复相陶瓷的抗热震性能明显高于单相B4C陶瓷的抗热震性能,而且BN/B4C纳米复相陶瓷的抗热震性能明显高于BN/B4C微米复相陶瓷的抗热震性能。BN/B4C微米复相陶瓷和BN/B4C纳米复相陶瓷具有良好的抗热震性能主要是由于具有较高的抗弯强度和较低的弹性模量;同时BN/B4C复相陶瓷中的BN/B4C弱界面和层状结构的h-BN晶粒能够显著提高复相陶瓷的抗热震性能。
新疆南天山西段震群活动特征分析
Characteristics of Earthquake Swarms in Western Partof South Tianshan,Xinjiang
 [PDF]

张琳琳,宋春燕,温少妍
- , 2016, DOI: 10.3969/j.issn.1000-0844.2016.05.0822
Abstract: 2008年3月-2013年12月新疆南天山西段小震群活动水平较高,系统整理该地区31次小震群,并对震群活动的参数特征进行分析总结,以探讨小震群活动与中强地震的关系,同时检验前兆震群类型的判断指标。结果表明:(1)新疆南天山西段震群活动集中,强度以ML2.0~3.9地震为主,震群中最大震级多数为ML3.5左右,而震级值ML≥4.0共7次,最大为ML4.9,震群序列总频次多数小于20,持续时间大多为7天以内;震群序列中地震总频次和震群持续时间与震群中最大地震震级之间不成正比。(2)震群活动主要集中在阿图什附近,75%震群发生两个月后对应M5.0以上中强地震,对应范围为0~500 km,未来中强地震震中位置主要集中在喀什-乌恰交汇区,震群强度大小与未来中强地震的对应率高低值和对应的地震强度大小之间没有明显的相关性,震群序列频次与震群的地震对应率之间也不存在相关性。(3)采用U-K和U-ρ组合方法判定震群类型的检验效果相对较好,正确率约占总数的32%。分析结果可以为判断震群活动是否具有前兆特征和震情跟踪提供参考依据。
The small earthquake swarm activity level in South Tianshan,Xinjiang,was relatively high from March 2008 to December 2013.In this paper,31 small earthquake swarms occurring in this area are systematically studied,the parameter characteristics of earthquake swarms are summarized,the relationship between small earthquake swarms and the occurrence of future moderately strong earthquakes is discussed,and criteria for precursory earthquake swarms are analyzed and tested.Results show that:(1) earthquake swarms in South Tianshan are concentrated in several regions,the magnitudes of most are 2.0~3.9,and the largest magnitude of each swarm is mostly about ML3.5.Seven swarms have a total magnitude of ML ≥ 4.0 with a maximum value of ML4.9 and there are less than 20 earthquakes for most earthquake swarms with a duration of less than seven days.(2) The activity of earthquake swarms is mainly concentrated near Atushi.75% of the swarms are accompanied with M>5.0 earthquakes two months after their occurrence,and the epicenters of these medium-strong earthquakes are principally located in the intersection of Kashi and Wuqia.The corresponding ratio of the magnitude of earthquake swarms and future medium-strong earthquakes has no obvious correlation with the magnitude of corresponding earthquakes.There is also no good relationship between the number of earthquakes in an earthquake swarm and the corresponding ratio.(3) Results using the combined method of U-K and U-ρ are preferable for determining the type of earthquake swarm,and the correct rate accounts for about 32% of all results.Results of analysis provide a reference for determining whether an earthquake swarm has precursory characteristics or not.
城市避震救灾最优体系模型仿真
Model Simulation of the Optimal System forUrban Earthquake Disaster Relief
 [PDF]

陈越平
- , 2018, DOI: 10.3969/j.issn.1000-0844.2018.05.1105
Abstract: 传统GIS空间分析模型进行城市避震救灾疏散方案规划时,未考虑疏散路径的当量长度,获取的避震救灾模型疏散效率较低。采用通行难度系数、次生灾害干扰系数、桥梁阻碍系数获取避震救灾疏散路径当量长度;通过目标函数获取避震救灾疏散路径当量长度的最小值,同时考虑避难场所的容纳量要求、清空避难场所固有人员、疏散距离小于避难场所的服务半径3个约束条件,设计新的城市避震救灾疏散最优模型。实验结果表明,新的城市避震救灾疏散最优模型能够给出精确的疏散路径与方案,高效率地完成城市避震救灾疏散任务。
When the traditional GIS spatial analysis model is used to plan an urban earthquake evacuation scheme, the equivalent length of the evacuation path is not taken into account, and the evacuation efficiency of the obtained model is relatively low. Therefore, a new optimal evacuation model for urban earthquake disaster mitigation and relief has been designed. The equivalent length of the evacuation path was obtained by using the difficulty coefficient of passage, interfe-rence coefficient of secondary disaster, coefficient of bridge obstruction, and minimum equivalent length of evacuation path, all of which were obtained by objective function. Simultaneously, the new model accounted for the capacity requirement of the shelter, the emptying of personnel from the shelter, and the evacuation distance being less than the radius of service of the shelter. The experimental results showed that the new optimal model can give an accurate evacuation path and scheme, and efficiently accomplish the evacuation task of urban earthquake disaster mitigation and relief.
基于同震GPS数据的汶川大震同震应变特征研究
Research on the Coseismic Characteristics of Strain of the Wenchuan Earthquake Based on GPS Data
 [PDF]

焦佳爽,张永志,张凯南,杨珍,姜永涛,南康康
- , 2017, DOI: 10.3969/j.issn.1000-0844.2017.02.0227
Abstract: 利用同震GPS观测数据,采用多面函数法,以数据分片拟合方式对2008年5月12日汶川MS8.0大震同震面应变进行计算,评定了计算结果的精度,并分析与强震有关的面应变变化特征。结果表明:在计算同震应变变化时,分片拟合较整体拟合得到的应变结果精度更高;同震应变结果对龙门山断裂能量释放特征及地表破坏分布有一定的反映。
In this paper, coseismic GPS data and the multisurface function are first used to calculate the coseismic surface strain caused by the MS8.0 Wenchuan earthquake that occurred on May 12, 2008 based on a piecewise data fitting method. The accuracy of the calculations is assessed, and the variation characteristics of surface strain related to the earthquake are analyzed. Calculation of coseismic strain changes revealed that the strain results obtained by piecewise fitting way are more precise than those determined by overall fitting. The calculation results of the two fitting methods feature the same order of magnitude, and the spatial distributions of the two images show some similarity. Compared with the results of the overall fitting method of multidimensional functions, the coseismic surface strain expansion and compression zones determined by the piecewise fitting method are more concentrated in the spatial distribution image. The results of this paper were compared with those of numerical simulation, and findings indicated that the calculation results of piecewise fitting are reliable. Coseismic strain appears to reflect the energy release characteristics and ground destruction distribution of the Longmenshan fault. The Wenchuan earthquake caused intense crustal shortening in the northern region of the Longmenshan fault zone. After the earthquake, the Longmenshan sub-block and the Sichuan basin sub-block moved in opposite directions with high speed over a short period of time. In the near-field region, several major aftershocks occurred in some areas where the coseismic horizontal displacement is amplitude. The coseismic surface strain highlights the right lateral slip characteristic of Wenchuan earthquake and the characteristics of uneven compression at the northwestern side of the Longmenshan fault zone are demonstrated. The results show different strain attenuation characteristics at both sides of the Longmenshan fault. Taken together, findings in this study may be used to determine the characteristics of horizontal crustal movement caused by the MS8.0 Wenchuan earthquake in a more intuitive manner.
福建仙游震群序列发震构造分析研究
Analysis of the Seismogenic Structure of the Xianyou Earthquake Swarm Sequence in Fujian Province
 [PDF]

秦双龙,邱毅
- , 2018, DOI: 10.3969/j.issn.1000-0844.2018.06.1306
Abstract: 福建仙游地区自2010年8月开始出现地震序列活动,2012年地震活动水平有所提高,2013年以来地震活动水平进一步提高,ML3.0以上地震集中活跃。福建数字化地震台网对这些地震进行了较完整的监测,记录到丰富的观测资料。通过利用P、S波到时数据对ML ≥ 1.0地震序列进行重新定位,发现地震序列空间位置和震源深度呈现出不同的时段性分布特征。同时利用福建数字化地震台网记录到的波形资料,采用"剪切-粘贴"法,获取了ML ≥ 3.5的震源机制解和最佳震源深度。通过震群序列活动特征、震源位置分布、震源区断层活动分布以及震源机制解特征综合判断认为:仙游震群序列为库水下渗促使断裂滑动引起的构造地震,属于水库诱发型构造型地震,发震构造为穿过库区的NW向石苍断裂。
Earthquake swarm activities have been occurring in the Xianyou area of Fujian Province since August 2010. The level of seismic activity increased in 2012 and further increased in 2013, when ML ≥ 3.0 earthquakes were concentrated. Sufficient observation data of these earthquakes were recorded by Fujian digital seismic network. In this study, the sequence of ML ≥ 1.0 earthquakes are relocated using the P-and S-wave arrival data, and it is found that both the spatial location and focal depth of the earthquake sequence show different distribution characteristics for different periods. Meanwhile, based on the waveform data recorded by Fujian digital seismic network, the focal mechanism solutions and the best focal depths of ML ≥ 3.5 earthquakes are obtained with the "cut and paste" method. According to the characteristics of earthquake swarm sequence, distribution of hypocenter location and fault activity in the hypocentral region, and the focal mechanism solution, it is concluded that the Xianyou earthquake swarm sequence are tectonic earthquakes caused by reservoir water infiltration and then fault slip, and thus, they are reservoir-induced tectonic earthquakes; in addition, the seismogenic structure is the NW-trending Shicang fault which passes through the reservoir area.
SiC复相陶瓷内加热器套管的抗热震及抗氧化性能  [PDF]
杨万利,史忠旗,李永锋,赵常见,乔冠军,金志浩
硅酸盐学报 , 2014, DOI: 10.7521/j.issn.0454-5648.2014.06.02
Abstract: 模拟内加热器服役环境,将具有复层结构的碳化硅(SiC)复相陶瓷内加热器套管置于金属铝液中,测试套管各部位材料的抗热震及抗氧化性能。通过X射线衍射和扫描电子显微镜研究材料成分和显微结构的变化,分析确定导致内加热器整体失效的原因及部位。结果表明SiC复相陶瓷套管内管材料在长效氧化条件下残余强度依然达到270MPa以上,不会导致套管整体失效;外管材料在氧化和热震双重作用下,液面至液面下100mm处的孔隙率明显增加,残余强度显著降低,这是导致内加热器整体失效的主要原因
太阳能热发电用堇青石-莫来石复相陶瓷的制备及抗热震性  [PDF]
徐晓虹,马雄华,吴建锋,张亚祥,劳新斌,张锋意
武汉理工大学学报 , 2012,
Abstract: ?以合成莫来石和合成堇青石为原料,采用常压烧结制备了太阳能热发电用堇青石?莫来石复相陶瓷。研究了质量比、烧结温度等对样品的吸水率、气孔率、体积密度、抗折强度及抗热震性等的影响。结果发现,最优配方是?1440℃?烧结的a3样品,堇青石和莫来石质量比为7∶3,气孔率为0.30%,吸水率为0.12%,体积密度为2.487g/cm3,抗折强度达68.49mpa,抗热震循环(室温~1100℃)30次无裂纹。通过xrd和sem分析发现样品由低温堇青石、高温堇青石和莫来石组成。该复相陶瓷可作为潜在的太阳能输热管道材料。
基于潮汐因子的河北省形变台站映震效能评估
Evaluation of Reflecting Earthquake Ability of DeformationStations in Hebei Province Based on Tidal Factors
 [PDF]

侯晓真,陈建国,马栋,屈曼,张肖,韩静,王时
- , 2018, DOI: 10.3969/j.issn.1000-0844.2018.05.1068
Abstract: 定点台站观测资料作为中短期地震预报的基础性资料,其质量好坏及台站映震效能对地震形势分析研判有重要作用。鉴于此,对“十五”网络化改造后,2008年以来河北省形变台站的观测资料进行潮汐因子计算及映震统计,通过梳理分析、归纳总结得出质量较好的形变台站及测项,用于辅助河北省地震形势研判。
The quality of observation data recorded by fixed stations and the reflecting earthquake ability of stations have a significant influence in seismic situation analysis and medium-short term earthquake prediction. Considering this, based on the observation data recorded by the deformation stations of Hebei Province since 2008 (after the network reconstruction of the tenth "Five Year Plan"), the tidal factors are calculated and the reflecting earthquake ability of the stations are analyzed in the study. Through the analysis and summary, deformation stations and observation items with good quality are obtained, which are highly useful in studying the earthquake situation in Hebei Province.
2013年山东莱州M4.6地震序列发震构造初探
Causative Structure of the 2013 Laizhou Earthquake Sequence
 [PDF]

曲均浩,杨玉永,刘永贵,范晓易,曲利,崔鑫,赵金花,钟普浴
- , 2015, DOI: 10.3969/j.issn.1000-0844.2015.02.0546
Abstract: 采用双差定位法对山东莱州地震序列重新定位,通过CAP方法反演M4.6地震震源机制,在此基础上初步探讨莱州地震序列发震构造。结果显示:精确定位震中位置主要位于柞村—仙夼断裂的NW方向,深度剖面显示从SE方向到NW方向断层深度呈由浅逐渐变深的趋势,这均与柞村—仙夼断裂位置、走向、倾向特征较为吻合;M4.6地震震源机制解的节面Ⅰ与柞村—仙夼断裂走向、倾角较为接近。综合精确定位震中位置、剖面深度分布特征、M4.6地震震源机制解及宏观调查烈度分布等结果与柞村-仙夼断裂产状之间的关系,初步推测柞村—仙夼断裂可能为莱州地震序列的发震断层。
The M4.6 earthquake in Laizhou,Shandong,occurred on November 23,2013,and it was the largest earthquake recorded since 1970.This event was also notable as the most potent earthquake in the interior regions since the M5.2 earthquake of Cangshan 18 years earlier.The Shandong Digital Earthquake Network Center has recorded 86 aftershocks until March 02,2014,including 18 earthquakes of more than ML2.0.The earthquake occurred between the Jingzhi and Yishu faults (along NE direction) with the Liucun-Laizhou,Zuocun-Xiankuan,Matou-Dagu faults around the epicenter.The focal mechanism describes the nature and source of the rupture process,and is an important foundation for understanding the stress state of the source region,earthquake faults,and analyzing the causes of the seismic event.Therefore,the determination of the earthquake focal mechanisms is of great significance in the understanding of the mechanical process of earthquakes,for seismic interpretation,and for the understanding of the post-earthquake seismogenic stress distribution mechanism.Thus the causative structure of the Laizhou earthquake sequence is discussed on the basis of relocating the Laizhou earthquake sequence using the double-difference method and analyzing the focal mechanism of the stronger earthquake using the "cut and paste"(CAP) method.Eighty-six earthquakes were relocated using the double-difference method,and 75 basic earthquake parameters were obtained. The precise epicenter was located along the direction of Zuocun-Xiankuan fault,which is consistent with the location,strike,and dip of the Zuocun-Xiankuan fault.The depth of the entire earthquake sequence was found from 4 to 9 km,and the advantages of depth was at 5~7 km.The result showed that the main earthquake rupture occurred in the upper crust.The analysis of the vertical profile by precise positioning showed that the focal depth from SE to NW gradually becomes deeper,and the dip direction is in the NW direction,which are consistent with location,strike,and dip of the Zuocun-Xiankuang fault.The focal mechanism of the 4.6 earthquake was inverted using the CAP method.Thus,the synthetic seismograms fit well with the observed seismograms,and the inversion result is verified.The focal mechanism showed that the moment magnitude of the M4.6 earthquake was MW =
Page 1 /100
Display every page Item


Home
Copyright © 2008-2017 Open Access Library. All rights reserved.