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1.
大姚地热动态特征分析 总被引:3,自引:1,他引:3
通过大姚高精度水温观测井水地质、井孔条件的分析,震例观测资料、实验观测数据的处理,以及井水水质分析结果,表明大姚水温周期性变化的突出位置是井深75m左右,根本原因是该地层石膏脉稳定释热,含水层热水与井内冷水混合过程中,在通道内形成钙盐类沉淀物(如CaSO4CaCO3),堵塞对流通道,含水层内外压差突破被阻塞通道,热水反复侵入井内,便形成水温周期性变化。地震的孕育、发生和调整过程,由于应力场作用,产生附加地热场,水温基值发生变化,周期畸变或消失,这种附加地热动态是可以恢复的。所以认为大姚地热动态是井区特殊地层地热信息的反映。 相似文献
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模糊数学在气象、水文预报领域中已经得到广泛的应用。其中,用隶属函数的方法作预报对象的多等级长期预报,能取得较好的效果。本文简要介绍用隶属函数的方法进行长期多等级预报的基本思路和步骤,重点介绍在作上述预报过程中,构造隶属函数的一种方法。 相似文献
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毛娟 《广东海洋大学学报》2006,26(5):105-108
芥川龙之介的《水虎》与果戈理的《狂人日记》、鲁迅的《狂人日记》均采用了现实主义与象征主义相结合的创作方法,一针见血地揭露了社会制度的黑暗与腐朽。但他们在创作方法上使用的象征主义和对社会现实揭露的广度与深度不完全相同,主人公的思想高度更是各不相同。作品创作的背景、历史条件,作者的思想高度、性格特点和创作风格是造成这些差别的根源。 相似文献
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The influence of volcanism on paleoclimate in the northeast of China: Insights from Jinchuan peat, Jilin Province, China 总被引:3,自引:0,他引:3
Just like contemporary sediments, peat itself is a good repository of information about climate change, the effects of volcanic
activity on climate change have been truly recorded in peat, since it is a major archive of volcanic eruption incidents. A
section of sand was identified as tephra from the Jinchuan peat, Jilin Province, China, for the grains look like slag with
surface bubbles and pits, characterized by high porosity, and loose structure with irregular edges and corners. According
to the peat characteristics of uniform deposition, the tephra was dated at 2002–1976 a B.P. by way of linear interpolation,
so the time of volcanic eruption was 15 B.C.–26 A.D. (the calibrated age). While the geochemical characteristics of tephra
in this study are quite the same as those of tephra from the Jinlongdingzi volcano at Longgang and from alkaline basaltic
magma, with the contents of SiO2<55%, and the similar contents to Al2O3 and Fe, but the contents of Na2O>K2O. We speculated that the tephra in this study came from the Longgang volcano group. Compared with 11 recorded volcanic eruption
events as shown on the carbon and oxygen isotope curves of the Jinchuan peat cellulose, it is obviously seen that adjacent
or large-scale volcanic eruptions are precisely corresponding to the minimum temperature and humidity. It seems that these
volcanic eruptions indeed affected the local climate, leading to the drop of regional temperature and humidity. As a result,
there was prevailing a cold and dry climate there, and all these changes can be well recorded in peat. So the comparison of
volcanic eruption events with information about climate change developed from peat, can provide strong evidence for the impact
of volcanism on climate change. 相似文献
8.
We have observed the massive star formation region W75N in 12CO J = 3 ? 2 with KOSMA. The profile of 12CO J = 3 ? 2 indicated that besides the 9 km s?1 component, there is another component of ?3 km s?1, which is associated with another star formation region, DR21N, located to the north of DR21. We derived the physical and dynamical parameters of the core and high velocity gas associated with the two components separately. Star forming activities were investigated, including outflows and infall analysis. The two regions overlap in space and are not connected in velocity. We found that the cloud–cloud collision scenario may not apply for the DR21/W75N case. 相似文献
9.
Ag‐modified TiO2 nanotube arrays (Ag/TiO2 NAs) were prepared and employed as a photocatalyst for degradation of 17α‐ethinylestradiol (EE2) and inactivation of Escherichia coli. The as‐synthesized Ag/TiO2 NAs were characterized by field‐emission scanning electron microscope (FESEM), X‐ray diffraction (XRD), and X‐ray photoelectron spectroscopy (XPS). It was found that metallic Ag nanoparticles were firmly deposited on the TiO2 NAs with the pore diameter of 100 nm and the length of 550 nm. Photocatalytic degradation of EE2 and inactivation of E. coli were enhanced effectively in an analogical trend using Ag/TiO2 NAs. In particular, Ag/TiO2 NAs exhibited the antimicrobial activity even in the absence of light. The Ag acted as a disinfection agent as well as the dopant of the modified TiO2 NAs photocatalysis by forming a Schottky barrier on the surface of TiO2 NAs. Inorganic ions suppressed the rates of photocatalytic degradation of EE2, with HCO having a more pronounced effect than NO or SO. Humic acid (HA) was found to increase the rate of EE2 degradation. 相似文献
10.
通过分析倾斜航摄仪的特点,提出一种面向倾斜影像的三维影像分辨率,介绍了3个方向分辨率概念以及推导了斜视影像分辨率的计算公式。结合当前市场上主流的倾斜航摄仪配置,分析了其影像分辨率变化的特点。本文得出的结论对航空摄影设计有重要指导意义,为影像量测精度分析打下了基础。 相似文献