重庆万盛煤矸石山自燃爆炸型滑坡碎屑流成因探讨

2 0 0 4 - 0 5 - 0 5重庆万盛胡家沟煤矸石山发生滑坡碎屑流灾害。灾害发生时,伴随巨大的响声和刺鼻气味,约2 0×10 4m3 煤矸石碎屑以极高初始速度崩滑而下,滑体横扫运动途中一切障碍,垂直坡降32 0m ,水平运动距离6 0 0m。造成重大人员和财产损失。通过实地考察和实验研究,作者认为煤矸石山中硫铁矿和碳氧化物升温,煤矸石山自燃、内部热量大量积聚所导致的煤矸石山的爆炸,是使大量矸石脱离矸石山形成此次煤矸石高速滑坡碎屑流灾害的主要原因     

利用爆破事件分析不同速度模型下常规定位方法定位结果

地震定位对速度模型的依赖性很强.四川地区地形复杂,常规工作中可选取多种速度模型进行定位.川西龙门山断裂带为东南部四川盆地和西北部青藏高原东部山区的明显分界线,近年在此断裂带上发生多次较大地震.对发生在该断裂带附近的6个爆破事件和15个天然地震重新定位,并对比结果.研究表明,相同台站包围情况下,川滇3D速度模型稳定性最好,但对浅表爆破不太准确.相比HypoSat(一维速度模型)组合,台站分布对Hypo2000(一维速度模型)和Hypo2000(赵珠速度模型)组合的定位结果影响较大.     

AP1000核电厂模型基底隔震振动台试验研究

为研究AP1000核电厂基底隔震性能,设计了缩尺比为1/40的AP1000核电厂模型结构,进行了AP1000核电厂模型基底隔震振动台试验。试验中采用铅芯橡胶隔震支座进行隔震,并选取RG1.60人工波、El Centro波和Kobe波作为地震动输入。本文从加速度响应、楼层加速度反应谱、加速度峰值放大系数、减震率等方面对隔震与非隔震核电厂结构的地震响应特性进行了研究。试验结果表明:隔震能明显减小上部结构水平向加速度响应和加速度反应谱峰值,而在隔震频率处隔震模型加速度反应谱有所增加;隔震模型由于摇摆效应在隔震频率处的水平向楼层加速度反应谱随楼层高度的升高先减小后增大;在三向输入地震动作用下,隔震和非隔震AP1000模型各楼层在竖向基频附近的竖向加速度反应谱较竖向输入的地震动放大较为明显。     

Some Thoughts on the Earthquake Science Experimental Site——The Underground Cloud Map

The Western Yunnan Earthquake Predication Test Site set up jointly by the China Earthquake Administration, the National Science Foundation Commission of America, and United States Geological Survey has played an important role in development of early earthquake research work in China. Due to various objective reasons, most of the predicted targets in the earthquake prediction test site have not been achieved, and the development has been hindered. In recent years, the experiment site has been reconsidered, and renamed the “Earthquake Science Experimental Site”. Combined with the current development of seismology and the practical needs of disaster prevention and mitigation, we propose adding the “Underground Cloud Map” as the new direction of the experimental site. Using highly repeatable, environmentally friendly and safe airgun sources, we could send constant seismic signals, which realizes continuous monitoring of subsurface velocity changes. Utilizing the high-resolution 3-D crustal structure from ambient noise tomography, we could obtain 4-D (3-D space + 1-D time) images of subsurface structures, which we termed the “Underground Cloud Map”. The “Underground Cloud Map” can reflect underground velocity and stress changes, providing new means for the earthquake monitoring forecast nationwide, which promotes the conversion of experience-based earthquake prediction to physics-based prediction.     

爆炸当量估算的初步研究

爆炸当量是评估爆炸能量的重要参数,快速估算爆炸当量对于有效开展应急救援工作至关重要。收集攀枝花铁矿爆破、宁夏煤矿爆破、河南汝阳钼矿爆破等矿山爆破资料,得到爆破的地方性震级M_L与爆炸当量Y之间的经验关系,并据此估算2019年7月19日河南省三门峡市气化厂爆炸事故的爆炸当量为16 t左右。     

缩短核磁共振测定冻土未冻水含量实验时间的方法

为利用核磁共振(NMR)技术更快地测试得到冻土中未冻水的含量, 首先对传统的单试样测试方法进行了分析, 探究了其实验时间过长的原因. 然后, 基于传热学中的集总参数法, 研究了小体积试样在空气中以自然对流传热为冷却方式的温度变化特征. 根据试样温度与时间的对应关系, 提出了多试样连续测试法. 最后, 以一种黏土为例, 分别利用多试样连续测试法和单试样测试法测量了土样冻结过程中NMR信号强度随温度变化的关系. 实验结果表明: 二者的测量结果非常接近, 但连续测试法耗费的时间非常少. 综合比较两种利用NMR技术所耗费的时间和实验结果的精确程度, 多试样连续测试法是可行的.     

柴达木盆地西部地下卤水水化学特征及成因分析

柴达木盆地西部有着丰富的地下卤水资源。通过野外实地考察取样,参考已有数据资料,选择了资源丰富,区域代表性强的柴达木盆地西部茫崖拗陷,特别是中部油墩子—南翼山背斜构造单元的地下油田卤水为主要研究对象;分析了其基本水化学特征,在此基础上初步探讨了卤水的成因、演化和物源信息,为进一步开发利用卤水资源,特别是评价其资源开发潜力有一定指导意义。     

http://dx.doi.org/10.1016/j.gsf.2016.09.005

We propose the nuclear geyser model to elucidate an optimal site to bear the first life.Our model overcomes the difficulties that previously proposed models have encountered.Nuclear geyser is a geyser driven by a natural nuclear reactor,which was likely common in the Hadean Earth,because of a much higher abundance of ~(235)U as nuclear fuel.The nuclear geyser supplies the following:(1)high-density ionizing radiation to promote chemical chain reactions that even tar can be used for intermediate material to restart chemical reactions,(2)a system to maintain the circulation of material and energy,which includes cyclic environmental conditions(warm/cool,dry/wet,etc.)to enable to produce complex organic compounds,(3)a lower temperature than 100℃ as not to break down macromolecular organic compounds,(4)a locally reductive environment depending on rock types exposed along the geyser wall,and(5)a container to confine and accumulate volatile chemicals.These five factors are the necessary conditions that the birth place of life must satisfy.Only the nuclear geyser can meet all five,in contrast to the previously proposed birth sites,such as tidal flat,submarine hydrothermal vent,and outer space.The nuclear reactor and associated geyser,which maintain the circulations of material and energy with its surrounding environment,are regarded as the nuclear geyser system that enables numerous kinds of chemical reactions to synthesize complex organic compounds,and where the most primitive metabolism could be generated.     

An advanced numerical model of elastomeric seismic isolation bearings

The nuclear accident at Fukushima Daiichi in March 2011 has led the nuclear community to consider seismic isolation for new large light water and small modular reactors to withstand the effects of beyond design basis loadings, including extreme earthquakes. The United States Nuclear Regulatory Commission is sponsoring a research project that will quantify the response of low damping rubber (LDR) and lead rubber (LR) bearings under loadings associated with extreme earthquakes. Under design basis loadings, the response of an elastomeric bearing is not expected to deviate from well‐established numerical models, and bearings are not expected to experience net tension. However, under extended or beyond design basis shaking, elastomer shear strains may exceed 300% in regions of high seismic hazard, bearings may experience net tension, the compression and tension stiffness will be affected by isolator lateral displacement, and the properties of the lead core in LR bearings will degrade in the short‐term because of substantial energy dissipation. New mathematical models of LDR and LR bearings are presented for the analysis of base isolated structures under design and beyond design basis shaking, explicitly considering both the effects of lateral displacement and cyclic vertical and horizontal loading. These mathematical models extend the available formulations in shear and compression. Phenomenological models are presented to describe the behavior of elastomeric isolation bearings in tension, including the cavitation and post‐cavitation behavior. The elastic mechanical properties make use of the two‐spring model. Strength degradation of LR bearing under cyclic shear loading due to heating of lead core is incorporated. The bilinear area reduction method is used to include variation of critical buckling load capacity with lateral displacement. The numerical models are coded in OpenSees, and the results of numerical analysis are compared with test data. The effect of different parameters on the response is investigated through a series of analyses. Copyright © 2014 John Wiley & Sons, Ltd.     

iTRAQ-based proteomic profiling of the marine medaka (Oryzias melastigma) gonad exposed to BDE-47

A recent study demonstrated that 2,2′,4,4′-tetrabromodiphenyl ether (BDE-47) may have an adverse effect on the reproduction in marine medaka (Oryzias melastigma), but the molecular mechanisms remain largely unknown. In this study, we investigated the protein expression profiles of male and female gonads of O. melastigma exposed to dietary BDE-47 at two dosages (0.65 and 1.30 μg/g/day, respectively) for 21 days. Extracted proteins were labeled with iTRAQ and analyzed on a MALDI TOF/TOF analyzer, as results, 133 and 144 unique proteins were identified in testis and ovary, respective, and they exerted dose- and sex-dependent expression patterns. In testis, among the 42 differentially expressed proteins; down-regulation of histone variants and parvalbumins implicated BDE-47 may disrupt the spermatogenesis and induce sterility in fishes. In ovary, 38 proteins were differentially expressed; the elevation of vitellogenins and apolipoprotein A–I expression indicated BDE-47 acts as an estrogen-mimicking compound and led to reproductive impairment in O. melastigma.