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311.
A modified Hoek-Brown failure criterion considering the damage to reservoir bank slope rocks under water saturation-dehydration circulation 总被引:1,自引:0,他引:1
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
312.
通过一系列的部门政策和措施的论述,证明了我国各部门减缓政策和措施已经通过国内系统得到了报告和核证,显示了“可测量,可报告和可核实”(MRV)的实际部门应用,同时指出部门方案具有不同的度量、报告制度和核证程序,以及不同的减排效果。这些部门减缓行动的MRV特点为国际MRV的构建提供了案例基础。 相似文献
313.
谷川 《大地测量与地球动力学》2010,30(2):58-62
?????????????ó??????????????????????Ψ???????????????????????????????????п?????????????????;????????????????????????????????????????????????????????????ù???????????÷????????????????????????????? 相似文献
314.
着重分析研究华北地区第四活动期以来M_S≥5.0地震时空分布特征。结果表明,该地区第四活动期从1820年至1976年期间,地震活动出现了前后两次基本相似的强弱起伏活动过程,分别历时69年和66年。前后两个活动过程不但时序结构类似,进程一致,且空间演化格局相似,都是先从华北地区的中南部开始,再迁移至东北部辽东半岛及附近海域,最终在华北地区北部集中出现一系列强震活动,而完成整个活动过程。进一步分析表明,前后两活动过程的第一阶段6级以上强震,在空间分布上除南黄海地区外,基本上互不重复。这一现象的发现,有助于该地区今后地震活动主体区域的分析判断。 相似文献
315.
介绍了基于Web的流动地震监测数据库查询系统的开发背景和目的,描述了数据库查询系统的设计和实现过程。该系统借助Internet/Intranet网络,以B/S(浏览器/服务器)体系结构作为基础架构,采用WAMP集成化软件开发,具有系统加密、数据查询、数据维护、数据导出和资料下载等功能。 相似文献
316.
文中展示了南黄海中古生代沉积地层的成像结果,显示南黄海隆起区存在较稳定的中古生代沉积地层残留区.南黄海中古生代残留沉积地层的成像问题一直是地震资料处理的难点,主要原因是以海底鸣震为主的层间多次波和与中古生界顶界面相关的长程多次波非常发育,致使有效反射波无法准确识别.本文利用平面波域层间多次波的可预测性,对地震数据平面波分解之后进行预测反褶积,较好地消除了层间多次波.利用速度差异分离长程多次波,在有效波速度无法确定的条件下,先从低速的、可以确认的多次波开始进行分离,逐步确认并分离多次波,同时逐步进行有效波的确认和成像速度的尝试,最终得到合适的成像速度场和多次波被充分分离的数据.成像结果对南黄海残留盆地研究有一定借鉴意义. 相似文献
317.
LN-3A水位仪记录的高采样率大震水震波特点及仪器改进 总被引:1,自引:1,他引:0
分析了海南前兆台网水位仪对苏门答腊M_S 8.7地震和我国四川汶川Ms 8.0地震的高采样率水震波记录情况,从中可较明显地看到地震波引起的井水位详细变化,但也存在水震波的丢头、仪器时间存在误差,第一代仪器水震波相互覆盖等现象,提出了在水位仪中增加在线缓存记录、自动定时校时功能等改进建议。 相似文献
318.
We examined the structure and spatial organization of ciliature base-associated microtubules (BAM) in three hypotrichous ciliates
(Stylonychia mytilus, Pseudourostyla cristata, Euplotes woodruffi) in fluorescence microscopy. The results revealed that BAM, including the anterior (ALM), posterior longitudinal microtubule
(PLM) and the transverse microtubule (TM) bands, are composed of tubulin. The respective microtubular bands have cytoplasmic
polarization patterns that are significantly asymmetric. The BAM of the midventral files in P. cristata appear cord-shaped compared with the ALM bands of transverse cirri in both S. mytilus and E. woodruffi, which extend to the left anterior side of the cell before converging. The TM bands of the left marginal cirri (MC) in S. mytilus extend to the right side of the cell, while those of the right MC bands extend to the left. Our observations suggest that
BAM traits are common in hypotrichous ciliates even though different species possess different microtubule arrangements related
to the conserved cirral morphogenetic patterns in the respective species. The differing development of BAM in the three ciliate
suggests that the microtubules may be conserved in different hypotrichs. We have also demonstrated that the BAM, which appear
polar and asymmetric, are localized in specific cytoskeletal positions and extend in different orientations within the cortex
to connect with other ciliature-associated structures and, thus, strengthen the cortex. These BAM features indicate that they
are directly associated with cell motion. 相似文献
319.
The sequencing batch reactor (SBR) process has shown great success in the treatment of industrial wastewater from intermittent discharge factories and for the treatment of domestic wastewater from medium or small towns. As automation technology has developed, many studies have been conducted to determine the optimal conditions for the SBR process. This review outlines the progress and application of control strategies that have been developed for the SBR process and provides a summary and comparison of the advantages and disadvantages of various control strategies, especially fixed‐time control strategies and various real‐time control strategies. Moreover, an analysis and discussion of novel optimal control methods for biologic nutrient removal are provided. Although previous studies in this field have greatly enriched our understanding of SBR systems, it is clear that many unsolved problems remain. Therefore, a summary of unanswered questions regarding control strategies for the SBR process is provided and future research directions are suggested. 相似文献
320.
Study of a comprehensive assessment method of the environmental quality of soil in industrial and mining gathering areas 总被引:1,自引:0,他引:1
Yang Guan Chaofeng Shao Qingbao Gu Meiting Ju Xueju Huang 《Stochastic Environmental Research and Risk Assessment (SERRA)》2016,30(1):91-102
Industrial and mining activities have been recognized as major sources of heavy metal contamination in soil. Here, we developed a comprehensive assessment method for the soil environment in industrial and mining gathering areas based on the pressure–state–response model. Using this method, we assessed the environmental quality of soil in a typical industrial and mining gathering area in Tianjin City, China. The results are as follows: (1) The comprehensive environmental quality index of the soil in the study area was 0.532, which corresponds to an alert state and shows that the soil environment is generally poor. (2) The pressure, state, and response indexes were 0.609, 0.634, and 0.163, respectively, which suggests that the pressure in the soil environment of the study area is barely acceptable, and the state is merely passable. Furthermore, the response measures are not ideal. (3) The low response index scores indicate poor production processes, low pollutant treatment level, and unsatisfactory level of management by the enterprises in the study area. (4) The distribution of soil risks was found to be inseparably related to that of contamination sources and land use types. Furthermore, the distribution was uneven to a certain degree. Finally, we propose recommendations for the optimization, adjustment, and management of typical industrial and mining gathering areas with petrochemical, metallurgy, and other heavily polluting enterprises. 相似文献