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891.
膨胀土的矿物组成与膨胀特性关系的试验研究 总被引:15,自引:1,他引:15
介绍了用χ射线衍射法、热分析和次甲基兰-氯化亚锡定量蒙脱石等方法,对采自我国十省的膨胀土进行了矿物组成特性方面的试验研究。并讨论了它们与膨胀土的膨胀势等的关系 相似文献
892.
Self-protective behavior by residents of flood-prone urban areas can reduce monetary flood damage by 80%, and reduce the need
for public risk management. But, research on the determinants of private households’ prevention of damage by natural hazards
is rare, especially in Germany. To answer the question of why some people take precautionary action while others do not, a
socio-psychological model based on Protection Motivation Theory (PMT) is developed, explaining private precautionary damage
prevention by residents’ perceptions of previous flood experience, risk of future floods, reliability of public flood protection,
the efficacy and costs of self-protective behavior, their perceived ability to perform these actions, and non-protective responses
like wishful thinking. The validity of the proposed model is explored by means of representative quantitative telephone surveys
and regression analyses, and compared with a socio-economic model (including residents’ age, gender, income, school degree
and being owner or tenant). Participants were 157 residents of flood-prone homes in Cologne, Germany, a city that has traditionally
been subject to minor and major flood events. Results of the study show the explanatory power of the socio-psychological model,
with important implications for public risk communication efforts. To motivate residents in flood-prone areas to take their
share in damage prevention, it is essential to communicate not only the risk of flooding and its potential consequences, but
also the possibility, effectiveness and cost of private precautionary measures. 相似文献
893.
The paper deals with a methodology for quantitative landslide hazard and risk assessments over wide-scale areas. The approach was designed to fulfil the following requirements: (1) rapid investigation of large study areas; (2) use of elementary information, in order to satisfy the first requirement and to ensure validation, repetition and real time updating of the assessments every time new data are available; (3) computation of the landslide frequency of occurrence, in order to compare objectively different hazard conditions and to minimize references to qualitative hazard attributes such as activity states. The idea of multi-temporal analysis set forth by Cardinali et al. (Nat Hazards Earth Syst Sci 2:57–72, 2002), has been stressed here to compute average recurrence time for individual landslides and to forecast their behaviour within reference time periods. The method is based on the observation of the landslide activity through aerial-photo surveys carried out in several time steps. The output is given by a landslide hazard map showing the mean return period of landslides reactivation. Assessing the hazard in a quantitative way allows for estimating quantitatively the risk as well; thus, the probability of the exposed elements (such as people and real estates) to suffer damages due to the occurrence of landslides can be calculated. The methodology here presented is illustrated with reference to a sample area in Central Italy (Umbria region), for which both the landslide hazard and risk for the human life are analysed and computed. Results show the powerful quantitative approach for assessing the exposure of human activities to the landslide threat for a best choice of the countermeasures needed to mitigate the risk.An erratum to this article can be found at 相似文献
894.
榴辉岩退变质过程中的微量元素地球化学行为:对CCSD主孔退变质榴辉岩的研究 总被引:2,自引:2,他引:2
对中国大陆科学钻探工程主孔榴辉岩退变质过程中的微量元素地球化学行为进行了研究。对退变质程度连续变化样品的不同部分的对比研究表明,流体作用下的退变质过程中大离子亲石元素(Cs、Rb、Ba、Sr、K、Th、U)和轻稀土元素表现出较大的活动性,重稀土元素和高场强元素变化相对较小。退变质后大离子亲石元素的显著增加和高场强元素、重稀土元素的轻微变化(甚至相对降低),表明与退变质作用有关的流体中的络阴离子含量很少,并不富集高场强元素和重稀土元素。退变质后总体上表现出的Si、大离子亲石元素和轻稀土元素的明显变化,表明外来流体参与了榴辉岩的退变质过程,带入和带出了一些元素。结合榴辉岩中单矿物微量元素组成以及前人对D^Mineral/Fluid的研究成果,对流体-榴辉岩作用形成的退变质分带(富石英条带→角闪岩→退变质榴辉岩→新鲜榴辉岩)的微量元素组成变化进行了详细研究。结果表明在流体作用下的榴辉岩退变质过程中,大离子亲石元素、轻稀土元素和高场强元素含量的变化除了受退变质流体性质的影响外,更大程度上取决于退变质过程中的矿物相(尤其是副矿物)的变化。 相似文献
895.
句容磨盘山高速公路隧道工程地质勘探中,发现龙王山组逆覆在浦口组之上,又被Q1-2砾石层不整合覆盖。据该现象所处的空间位置可以认为,该断裂即为茅西断裂,其活动时间应在K2p浦口组沉积之后,且有一组(至少两条)断裂组成。 相似文献
896.
软土流变性对深基坑周围地表沉降的影响分析 总被引:1,自引:0,他引:1
在实测资料和前人研究的基础上,分析了软土地区深基坑围护结构水平位移值和墙后地表沉降的变化规律。对围护结构水平位移进行二次曲线拟合,假设地表沉降曲线形态可用正态分布密度函数来描述,利用地层损失法计算各工况下墙后最大地表沉降,并与各工况下实测最大地表沉降比较,提出了软土流变性对地表沉降规律的滞后影响。 相似文献
897.
Marine mammals and marine birds perform diving to forage underwater. Recent technological advances have led to rapid progress in our understanding of diving behavior, but additional research is required into feeding behavior to determine the timing of prey ingestion, prey mass, and prey type. To achieve a comprehensive understanding of the foraging and diving behavior of these endotherms, it is essential to integrate information on feeding behavior with other data. The challenges involved in developing an appropriate research method have been addressed, and several methods have been tested and used in the field, including the stomach temperature method, the esophagus method for marine birds, the stomach temperature telemeter method for seals, and the beak magnet sensor method. In the present study, I review these methods, suggest the necessity of their further development in field studies, and propose a new practical method that involves the measurement of jaw movements underwater as an indicator of the feeding behavior of seals. 相似文献
898.
利用行为地理学的方法,选取湖南省益阳市为调查地点,对城区居民不同商品类型的购物行为进行调查,分析了居民购物出行的一般特征、空间特征,在此基础上得出了居民购物出行的圈层结构。通过问卷的科学分析并将结果与已有国内大城市研究结果对比,得到了如下结论:(1)中小城市居民购物出行一般特征与大城市具有很大相似性,符合购物出行一般特征的普遍规律。(2)居民购物出行呈明显的圈层结构,但与大城市不同,中小城市呈现不连续的区间分布。(3)中小城市居民出行呈现被动购物型特征。(4)城市商业空间结构、距离、价格、商品质量为居民购物出行的重要影响因素。 相似文献
899.
叶艳霞 《云南地理环境研究》2007,19(5):69-72,76
旅游消费者行为的研究是跨学科的,涉及人口学、经济学、社会学、心理学、地理学等方面的内容.利用行为地理学的理论与方法,在微观层面对旅游消费者行为和感知进行研究,以湛江-北海游的团队旅游消费者为对象,进行实证分析.调查发现,旅游消费者的感知和行为存在着密切关系.旅游消费者的偏好、休闲时间及经济条件是影响旅游消费者行为的三个重要因素.由游前的感知和游后的映象对比表明,家庭型的旅游消费者偏好于选择休闲型目的地,且需要安全和熟悉的外部环境.同时基于行为地理学方法在调查中的不足,提出了反思. 相似文献
900.