盐湖提锂副产氢氧化镁绿色合成镁基层状复合氢氧化物

青海盐湖资源丰富,在盐湖提锂过程中副产了大量含锂Mg(OH)2镁渣,由于利用条件和工艺的限制,其大部分被企业堆置放弃,造成资源的严重浪费和生态环境的破坏,因此提锂副产镁渣的高值化利用具有重要的意义.本研究仅采用盐湖提锂副产镁渣和可溶性铝盐作为原料,采用水热法成功制备了SO2-和CO32-插层的镁基层状复合金属氢氧化物(...     

不同条件下乌梁素海污染物在冰-水体系中分布规律的模拟

为探讨单一因素(如浓度、温度、酸碱度)对冰封期乌梁素海中营养盐和盐分(总氮、总磷、Na+和Cl-)迁移的影响,对不同条件下各物质水样进行室内单向结冰模拟,分析总结物质在冰层和冰下水层中的分布特征,并用分配系数(K)来表征.结果表明:冰体中物质浓度随水样初始浓度(C0)的增大而增大,随结冰温度的升高而减小;各物质在冰体中的浓度分布表现为顶层中层底层.总氮、总磷的分配系数K随C0的增大呈递减趋势,Na+和Cl-的K值随C0的增大呈递增趋势;对各条件下的K值进行假设检验,结果为:水样中物质初始浓度和结冰温度显著影响其在冰-水体系中的分布;同一温度下,C0较小时,酸碱度显著影响各物质在冰-水体系中的分布,C0较大时,酸碱度显著影响Na+和Cl-在冰-水体系中的分布,但对总氮、总磷浓度分布的影响不显著.可见,在不同环境因素下,各物质在冰-水体系中表现出不同的分布特征,对此进行模拟可为寒区湖泊污染物迁移和生物地球化学循环的研究提供一定的参考.     

地震行业骨干网“一网双平面”架构

通过对地震行业现有骨干网络架构的优缺点进行分析,阐述"一网双平面"骨干网架构在地震行业骨干网的通信质量、可靠性、资源有效利用等优势,从建设成本、组网策略、业务分流、网络与信息安全等方面提供建议,为地震行业骨干网进一步优化、实现承载业务系统的安全高效运行提供参考。     

2015年11月22日广东徐闻M_L 4.2地震震源机制解及精定位分析

基于海南地震台网数字波形资料,采用CAP方法对2015年11月22日广东徐闻M_L 4.2地震反演震源机制解,计算得出节面Ⅰ参数:走向110°,倾角84°,滑动角-158°;节面Ⅱ参数:走向18°,倾角69°,滑动角-5°。推断为1次走滑为主兼有正断性质的破裂,与铺前—清澜断裂属于走滑正断的运动特征较为吻合。对2000年1月—2016年6月主震周边地区(19.3°—20.6°N,110.0°—111.0°E)M_L1.0以上183次地震进行双差精定位分析,得到146次地震的重定位结果。结果显示:震源深度分布不再仅局限于10 km附近,而是呈垂直带状分布,与雷琼地区新构造运动主要以垂直差异性活动为主的活动特征相吻合。     

VELOCITY STRUCTURE TOMOGRAPHY OF REGIONS DOWNSTREAM THE JINSHA RIVER BASED ON DENSE OBSERVATION

In this paper, the double difference seismic tomography method is applied to the phase arrival times of 7 465 seismic events to determine the hypocenter parameters of events as well as detailed 3D velocity structure at the northern segment of Xiaojiang Fault and its surrounding area. The data was recorded by 42 stations of the Jinshajiang River network from August 2013 to November 2016. At 2~6km, V_P and V_S present low velocity anomalies along the northern segment of Xiaojiang Fault, and the V_S anomaly is especially remarkable. On both sides of the Xiaojiang Fault, there also exist obvious P and S wave low velocity areas. These low velocity areas correspond to the terrain, lithology distribution and the watershed of Jinsha River at shallower layer in the study area. Starting from 6km, a NE-directed high V_P band along Zhaotong-Ludian and Huize-Yiliang Fault is formed on the eastern side of the northern segment of Xiaojiang Fault. V_S also shows the high value in the area bounded by Lianfeng Fault, Baogunao-Xiaohe Fault and Huize-Yiliang Fault. Above 10km depth, to the west side of the Xiaojiang Fault including the Ninghui Fault, V_P shows a significant low-velocity anomaly, while to the east side it presents high velocity feature. The Xiaojiang fault zone shows a significant low V_P from north to south in the study region, and the low velocity anomaly in the northern segment is relatively significant, especially the low velocity anomaly area reaches 15km deep around Qiaojia area. Beneath the Baihetan Dam, a significant low V_P area reaching to 5km deep is found. The earthquakes around the dam formed a strip from shallow to deep on the low-velocity area side. Whereas, a stable high-velocity area is found under the Wudongde Dam. The events relocation result shows that:all the focal depths in the study area are shallower than 20km, and the predominant focal depth is within 15km. Different from the NE-trending of the major faults in the study area, the relocated seismic events are obviously distributed nearly east-west along Matang Fault and Daduo Fault and the region around Huize. The focal depths of M_S6.5 Ludian earthquake sequences are shallower than 15km, and mostly less than 10km. The aftershocks within 2a after the Ludian M6.5 earthquake form two predominant bands of about 40km and 20km along near EW and SN direction, respectively.     

非饱和土三剪强度准则及验证

基于材料三剪强度准则和非饱和土力学特性,提出了非饱和土的单应力变量和双应力变量三剪强度准则,并对其做了特征分析。分析表明,通过改变准则中的主应力影响系数b,所提准则就可以对其他强度准则进行非线性近似表达。在π平面的极限线中,所提强度准则覆盖了由内边界的单剪强度准则到外边界的三剪统一强度准则之间的所有外凸区域。因此,其适用于各种复杂应力状态下的非饱和土体,也能反映非饱和土单轴抗拉抗压强度不等的特征。另外,还用其他文献的真三轴试验数据对所提准则做了试验验证,其中,非饱和黏土砂的真三轴试验值与中主应力影响系数b=0.6时的三剪强度准则预测值吻合较好,双应力变量下准则的预测值比单应力变量下的预测值更符合试验值;非饱和黄土真三轴试验值与中主应力影响系数b=0.2时的三剪强度准则预测值吻合较好,两种应力变量下的三剪强度准则预测值差别较小。     

软土地区双排桩门架式挡墙的分析和应用

介绍了双排桩的二种计算模式及其在实践中的应用,并和实际监测进行了比较。     

Geodynamics of the divergent double subduction along the Bangong-Nujiang tethyan suture zone: Insights from late mesozoic intermediate-mafic rocks in central Tibet

Bangong-Nujiang Suture Zone (BNSZ) in central Tibet plays an important role in evaluating the formation and uplift mechanism of Tibetan Plateau. However, its Mesozoic tectonic evolution is ambiguous and intensely debated. In this study, Early Cretacesous adakites and sodium-rich arc rocks are identified in Western Qiangtang (WQ) and Northern Lhasa (NL) sub-terranes. Forty-four adakite samples from both WQ and NL have akin geochemical features, and are derived from partial melting of subducted oceanic crust with amphibole residual. Nineteen sodium-rich samples originated from a mixed source region between crustal sediment and enriched lithospheric mantle. These two parallel arc belts separated by the Bangong-Nujiang Suture Zone (BNSZ) represent the divergent double subduction of the Bangong-Nujiang Tethyan Ocean (BNTO). Combined with the previous studies, our new data suggest three significant magmatic flare-ups at ∼240–140 Ma, 135–105 Ma and 92–60 Ma in the WQ and BNSZ, and two at 135–105 Ma and 92–60 Ma in the NL. These asymmetrical magmatic activities indicate that the southern subduction may have commenced at about 135 Ma and experienced slab breakoff at the latest Early Cretaceous, and the northern subduction could trace back to L-Triassic (228 Ma) and experienced episodic low-angle subduction, slab rollback (190-140 Ma) and oceanic ridge subduction (135-100 Ma). The 100–92 Ma magmatic gap, 92–60 Ma magmatic flare-up and L-Cretaceous angular unconformities indicate that the double-sided subduction of the BNTO resulted in soft collision with oceanic lithosphere detachment.     

触发闪电环境下地网冲击接地电阻特征分析

基于触发闪电技术,研究了2019年夏季8次触发闪电44次回击、5次初始连续电流脉冲（ICCP）和24次M分量对冲击接地电阻的影响,探索了冲击接地电阻随雷电流注入的动态变化规律。结果发现：闪电放电ICCP、M分量和回击过程冲击接地电阻均小于工频接地电阻,ICCP和叠加在回击回落之后连续电流上的M分量冲击接地电阻略大于回击过程,平均值分别为11.2Ω和10.8Ω。叠加在回击下降沿上的M分量冲击接地电阻平均值7.8Ω,明显小于回击过程,最小值可达2.4Ω。ICCP和M分量冲击接地电阻随电流增加而减小,回击过程与电流峰值没有明显的相关性。叠加在回击下降沿上的M分量冲击接地电阻随雷电流峰值、背景电流值的增加呈指数衰减关系,还与之前回击电流峰值成一定的反比例关系。随着闪电回击电流的注入,冲击接地电阻呈现动态变化过程,小电流在回击峰值下降后出现一个缓慢增长的过程,大电流在回击峰值下降后出现一个快速下降的过程。闪电不同物理过程火花和电感效应的作用是不同的,两者共同作用决定了土壤的电离程度,从而决定了冲击接地电阻的大小和变化。     

高承台下自由桩长对双薄壁墩连续刚构桥地震响应的影响

为探究高承台下自由桩长对双薄壁墩连续刚构桥地震响应的影响,基于OpenSees程序建立了实桥有限元模型并进行弹塑性时程分析,通过对比不同自由桩长模型的时程曲线、峰值响应及滞回特性,分析了自由桩长对桥梁地震响应的影响.结果表明:自由桩长增加会减小桥梁刚度;地震作用下,随自由桩长增加,主梁、支座及自由桩顶的水平位移增大,且...