会昌台洞体形变观测资料干扰分析

对会昌台数字化洞体形变观测资料的干扰因素进行了分析。分析结果表明,会昌台大多数洞体形变观测资料稳定可靠,年变动态清晰,受气象因素影响不大,形变与洞温相关性较好,年变受控于洞温变化。雷电击坏仪器导致断记是影响连续率的主要因素,更换仪器可能对形变的趋势变化造成一定影响。     

广西岩溶洞穴沉积物与地震记录初探

广西是西南地区的一个岩溶大省,其岩溶面积占土地面积的42%.广西岩溶洞穴十分发育,至少有6万个洞穴.洞穴景观资源丰富,为广两的旅游创造了大量的财富.岩溶洞穴沉积物不仅具有旅游开发价值,而且蕴含了丰富的古气候环境信息,同时,也是地震信息的存储器,是研究地震遗迹的良好材料.地震活动不仅导致岩溶洞穴及洞穴沉积物发生破裂、坍塌...     

Effects of Density and Viscosity in Modeling Heat as a Groundwater Tracer

Decoupled simulation of groundwater flow and heat transport assuming constant fluid density and viscosity is computationally efficient and simple. However, by neglecting the effects of variable density and viscosity, numerical solution of heat transport may be inaccurate. This study investigates the conditions under which the density and viscosity effects on heat transport modeling can be neglected without any significant loss of computational accuracy. A cross-section model of aquifer-river interactions at the Hanford 300 Area in Washington State was employed as the reference frame to quantify the role of fluid density and viscosity in heat transport modeling. This was achieved by comparing the differences in simulated temperature distributions with and without considering variable density and viscosity, respectively. The differences between the two sets of simulations were found to be minor under the complex field conditions at the Hanford 300A site. Based on the same model setup but under different prescribed temperature gradients across the simulation domain, a series of heat transport scenarios were further examined. When the maximum temperature difference across the simulation domain is within 15°C, the mean discrepancy between the simulated temperature distributions with and without considering the effects of variable density and viscosity is approximately 2.5% with a correlation coefficient of above 0.8. Meanwhile, the speedup in runtime is roughly 225% when the maximum temperature difference is at 15°C. This work provides some quantitative guidelines for when heat transport may be simulated by assuming constant density and viscosity as a reasonable compromise between accuracy and efficiency.     

Hydrologic control of waveforms on small meandering rivers

Small river channels within the Humber Basin of Southern Ontario exhibit irregular meandering patterns; however, contemporary river hydrology appears capable of controlling the scale of regular waveform development. Recent changes in river planform are assessed through a bi‐temporal comparison of channel planform using orthorectified aerial photography and statistical analysis of curvature series based on autocorrelation and spectral analysis. Calculated meander wavelengths are acceptable given traditional relationships between wavelength and mean annual flood discharge. It is also evident that changes in stream power are highly correlated with changes in the dominant wavelengths between channel reaches in this study. Gradual development of small scale waveforms following a rare hydrological and geomorphological event in 1954 further confirms that these forms can be attributed to the typical discharge regime. This paper argues that the scaling of wavelengths with discharge can be considered a strong factor controlling planform evolution on some small meandering river systems, despite manifest irregular planforms. Copyright © 2007 John Wiley & Sons, Ltd.     

山洞温度对形变仪器的影响特征分析

简述太原基准地震台山洞温度的变化特征,对2012年12月24日至2013年7月出现温度趋势异常的原因进行分析,并进一步探讨温度变化对形变观测的影响,提出做好观测山洞保温工作的可行性建议。     

窑洞外形特征对结构抗震性能影响研究

调查发现山西北部农村地区农居窑洞多是独立式土坯窑洞,结构主要受力体系是土坯砌体砌筑拱结构,其建造无统一标准,外形样式存在差异。由于拱结构的内力分布对外形尺寸变化比较敏感,为研究窑洞外形特征对结构抗震性能影响,建立相应的有限元模型进行计算分析,对比不同外形特征窑洞在地震作用下的损伤情况,并结合历史震害,指出窑洞结构的薄弱位置。研究结果表明覆土较厚的窑洞容易损伤,连拱孔数较多窑洞的两侧位置更容易发生破坏,拱的曲线形状对结构抗震性能有一定影响,合理拱曲线窑洞的抗震性能优于一般形状窑洞。     

Effect of Initial Azo Dye Concentration and Biomass Acclimation on Sludge Digestion and Dye Co‐treatment

The effect of a reactive azo dye (the hydrolyzed form of Reactive Orange 107, HRO107) on the digestion of municipal waste sludge (WS) was studied. The study also focused on the effect of acclimation of the anaerobic mixed culture on dye treatment. Anaerobic batch assays were carried out in serum bottles under mesophilic conditions. Unacclimated and acclimated anaerobic mixed cultures were used for the study. Both unacclimated and acclimated anaerobic cultures completely reduced HRO107 during WS digestion. Inhibitory HRO107 concentration was found to be 800 mg/L for unacclimated mixed culture. Acclimation increased the inhibitory concentration level from 800 to 3200 mg/L. Sulfanilic acid and four other unidentified dye reduction end products were detected at the end of the assays. The results of this study indicated that anaerobic municipal WS digesters have the potential to be a cost efficient and effective pre treatment method.     

温度对洞体应变观测的影响及排除方法研究

本研究将相关性分析的概念扩展到局域化空间,提出局域化的相关性分析（Local-CC)技 术,作为对时间序列做定量化分析的基础;还提出了一套从形变观测数据的原始数据开始,探 讨测值对干扰的响应模型,并整合使用包括傅里叶变换（FFT)平滑滤波、局域化相关性（Locl CC)分析以及线性回归（LR),到最后差分减除在内的完整干扰减除方案,以达到消除温度变 化引起的干扰信息的目的。以昆明地震台的洞体温度记录及洞体应变观测NS向分量为例,使 用傅里叶变换（FFT)滤波器原理抽出较高频率的分量作为处理对象,并使用本文提出的局域 化的相关性算法,按照应变对温度在不同时间点上不同的相关性赋予权重;然后再利用这个权 重做线性回归分析,拟合出应变对温度的响应系数,以排除洞体温度对洞体应变观测的影响。结果显示,本文提出的方案能有效地排除温度对洞体应变观测的影响。     

Toxicological effects of biocide Slimicide C-30 on some marine invertebrates

Sublethal and lethal effects of biocide Slimicide C-30 on the developmental stages of mussels Mytilus galloprovincialis and juvenile and adult mysid Leptomysis mediterranea were studied.Biocide at a concentration as low as 0.02 mg l^?1 caused an incipient effect in the embryonic development of mussels where a decreased number of normally developed larvae from eggs was evident. Slimicide C-30 effective concentration (EC 50/96) was 0.07 mg l^?1.In the mysids, the median lethal concentration (96 h LC₅₀) was 0.11 mg l^?1.Previous incubation of Slimicide C-30 at 38°C affected a small delay in mortality time (LT₅₀) but did not cause marked change in the acute toxicity to mysids.     

Encapsulated Cell Bioremediation: Evaluation on the Basis of Particle Tracer Tests

Microencapsulation of degradative organisms enhances microorganism survivability (Stormo and Crawford 1994). The use of encapsulated cell microbeads for in situ biodegradation depends not only on microorganism survival but also on microbead transport characteristics. Two forced-gradient, recirculating-loop tracer experiments were conducted to evaluate the feasibility of encapsulated cell transport and bioremediation on the basis of polystyrene microsphere transport results. The tracer tests were conducted in a shallow, confined, unconsolidated, heterogeneous, sedimentary aquifer using bromide ion and 2 μm, 5 μn, and 15 μm microsphere tracers. Significant differences were observed in the transport of bromide solute and polystyrene microspheres. Microspheres reached peak concentrations in monitoring wells before bromide, which was thought to reflect the influence of aquifer heterogeneity. Greater decreases in microsphere C/C_o ratios were observed with distance from the injection wells than in bromide C/C_o ratios, which was attributed to particle filtration and/or settling. Several methods might be considered for introducing encapsulated cell microbeads into a subsurface environment, including direct injection into a contaminated aquifer zone, injection through a recirculating ground water flow system, or emplacement in a subsurface microbial curtain in advance of a plume. However, the in situ use of encapsulated cells in an aquifer is probably limited to aquifers containing sufficiently large pore spaces, allowing passage of at least some encapsulated cells. The use of encapsulated cells may also be limited by differences in solute and microbead transport patterns and flowpath clogging by larger encapsulated cell microbeads.     

Toxicological Effects Induced by Cadmium in Gills of Manila Clam Ruditapes philippinarum Using NMR‐Based Metabolomics

Cadmium (Cd) has become an important heavy metal contaminant in the sediment and seawater along the Bohai Sea and been of great ecological risk due to its toxic effects to marine organisms. In this work, the toxicological effects caused by environmentally relevant concentrations (10 and 40 µg L^?1) of Cd were studied in the gill tissues of Manila clam Ruditapes philippinarum after exposure for 24, 48, and 96 h. Both low (10 µg L^?1) and high (40 µg L^?1) doses of Cd caused the disturbances in energy metabolism and osmotic regulation and neurotoxicity based on the metabolic biomarkers such as succinate, alanine, branched chain amino acids, betaine, hypotaurine, and glutamate in clam gills after 24 h of exposure. However, the recovery of toxicological effects of Cd after exposure for 96 h was obviously observed in clam to Cd exposures. Overall, these results indicated that NMR‐based metabolomics was applicable to elucidate the toxicological effects of heavy metal contaminants in the marine bioindicator.