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121.
梁伟锋  祝意青  徐云马  刘练  郭树松  刘芳 《地震研究》2012,35(3):318-322,441
系统深入地分析了2005~2009年华北地区流动重力观测资料,提取2006年河北省文安县MS5.1地震前后0.5a、1a等不同时间尺度可靠的重力场动态变化信息,研究其与地震活动的关系。结果显示:文安地震孕育阶段,测区出现较大范围的区域性重力异常,并产生与地震孕育有关的局部重力异常区及重力变化高梯度带。重力场动态图像较清晰地反映了区域重力场的有序性演化与地震活动。  相似文献   
122.
地震地下流体观测现状   总被引:3,自引:1,他引:2  
系统介绍我国地震地下流体井(泉)的分布现状、观测井含水层特征及自流热水井的观测现状,并介绍观测项目及主要观测仪器等。上述调查与分析结果,可为我国地震地下流体台网的进一步调整与优化,及今后地震地下流体学科的发展提供科学依据。  相似文献   
123.
Destructions resulted from natural hazards like earthquake, landslide, or flood in the urban roads and lifelines introduce their negative effects including the psychological damage to citizens as well as decreased urban functions that usually last for a long time. Thus, a quick and efficient recovery of infrastructures, lifelines, and service-providing facilities along with reducing reconstruction costs and time are essential. This paper proposed an approach that consists of four models for forming an algorithm in order to quantitating and integrating of the criteria that have decisive influence in the recovery of urban roadways after a natural disaster. Meanwhile, to aggregate and conclude the data that are collected by means of presented functions and formulations, we applied fuzzy VIKOR technique as a compromise ranking method. The model outputs a priority list showing the revival of which urban paths stands in higher priority for recovery operation after a natural disaster. Results show that not only the model is able to precisely quantize the selected criteria and provide an action plan for post-event recovery prioritization, but also it offers an appropriate order of transportation roads priority for recovery operations. Finally, the results from the recovery model application to a roadway system in Tehran area are provided.  相似文献   
124.
<正>Two Mesozoic intramontane basins are developed in the Dunhuang-Yumenguan-Jiuquan area of Gansu Province,China,i.e.,the Gongpoquan Basin(E97°30′-98°10′,N41°30′-41°45′)and the Yujingzi Basin(E98°15′-99°00′,N40°15'-40°40')(Fig.1).A large number of dinosaurs and other fossils have been discovered in these two basins,which are called dinosaur'tribes'by paleontologists.  相似文献   
125.
<正>1 Dinosaur Eggs in Yiwu City,Zhejiang Province In February 2017,dinosaur egg fossils were discovered in Chian Town part of Yiwu City,Zhejiang Province.They were confirmed by dinosaur experts from the Zhejiang Museum of Natural History to be those of Mesozoic herbivorous dinosaurs(Fig.1).Not long before,Yiwu Museum staff had discovered dinosaur eggs close by this place.  相似文献   
126.
After water is impounded in a reservoir, rock mass in the hydro-fluctuation belt of the reservoir bank slope is subject to water saturationdehydration circulation (WSDC). To quantify the rate of change of rock mechanical properties, samples from the Longtan dam area were measured with uniaxial compression tests after different numbers (1, 5, 10, 15, and 20) of simulated WSDC cycles. Based on the curves derived from these tests, a modified Hoek- Brown failure criterion was proposed, in which a new parameter was introduced to model the cumulative damage to rocks after WSDC. A case of an engineering application was analyzed, and the results showed that the modified Hoek-Brown failure criterion is useful. Under similar WSDC-influenced engineering and geological conditions, rock mass strength parameters required for analysis and evaluation of rock slope stability can be estimated according to this modified Hoek-Brown failure criterion.  相似文献   
127.
《雷州歌谣话初集》系清末民初黄景星著述之研究雷州民歌的一部珍贵的历史文献,其所选雷歌数量众多,体裁各异,题材广泛,原汁原味,注重音义注解的翔实性与可靠性,编辑体例具有较强的科学性。作者对每首雷歌字词句篇的鉴赏曲尽其致,对雷歌"赋"、"比"、"兴"之叙述方式与"双关"、"顶针"、"回环"等修辞方式独抒己见,将雷歌分为"口头歌"、"班本歌"、"出榜歌"、"姑娘歌"四类,考辨出雷歌"源于清之雍康间,而盛于乾嘉,衰于咸同以后"之历史事实,值得研究雷歌的学人一读。  相似文献   
128.
Interdecadal and interannual variations of saline-alkali land area in Qian’an County, Jilin Province, China were comprehensively analyzed in this paper by means of satellite remote sensing interpretation, field flux observations and regional climate diagnosis. The results show that on the interannual scale, the impact of climate factors accounts for 71.6% of the total variation of the saline-alkali land area, and that of human activities accounts for 28.4%. Therefore the impact of climate factors is obviously greater than that of human activities. On the interdecadal scale, the impact of climate factors on the increase of the saline-alkali land area accounts for 43.2%, and that of human activities accounts for 56.8%. The impact of human activities on the variation of saline-alkali land area is very clear on the interdecadal scale, and the negative impact of human activities on the environment should not be negligible. Besides, changes in the area of heavy saline-alkali land have some indication for development of saline-alkali land in Qian’an County.  相似文献   
129.
目的:探讨小肠空气灌肠双源CT检查对小肠疾病的诊断价值。方法:15例临床怀疑小肠病变的患者,行双源CT检查前或后3天内行胶囊内镜检查。其中,男8例,女7例,年龄最大者42岁,最小者23岁。症状主要为腹痛10例,脓血便4例,不明原因消瘦1例,病程最长4年,最短1月。结果:胶囊内镜未见异常8例,双源CT检查亦未见异常;双源CT诊断克罗恩病4例,与胶囊内镜及临床诊断一致;胶囊内镜可疑肿瘤3例,双源CT发现2例并作出良恶性诊断,其中1例为空肠间质瘤,1例为回肠腺癌,经手术病理证实;仅1例胶囊内镜可疑3cm大小肿瘤,双源CT未见异常,结合MRI检查及临床,证实为假阳性。结论:小肠空气灌肠双源CT检查,不仅可以显示小肠器质性病变范围、与邻近结构的关系,而且可以结合临床鉴别炎性病变与肿瘤性病变,并对肿瘤性病变做出良恶性鉴别;还可以为胶囊内镜所见病变定位及排除假阳性问题。  相似文献   
130.
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