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61.
The time series of two continuously operating gas monitoring stations at Oldřišská and Nový Kostel located along seismoactive faults in the epicentral area of the NW Bohemian swarm earthquakes (Czech Republic) are compared with water level fluctuations in two boreholes positioned along these faults and with gas flux variations of a mofette at the Soos mofette field at 9 km distance. The seasonal trend of the monitored CO2 concentration with a maximum in November and a minimum in March/April is governed by groundwater temperatures, superimposed in spring by soil temperatures. CO2 concentration variations identified at Oldřišská are also reflected in gas flux variations in the Soos mofette and/or water level fluctuations of two boreholes. Variations in the gas monitoring recordings of station at Nový Kostel are also linked with variations at Oldřišská. In all data sets, diurnal variations generated by earth tides occur, reflecting a daily stress – fault permeability cycle. Additional stress interferes with this cycle. Significant, abrupt changes are attributed to geodynamic processes linked with seismic events, as revealed by local seismicity or by the transient of waves of a strong remote earthquake. Simultaneous variations of the gas concentrations in the Nový Kostel area and in the gas flux in the Soos point to an interconnected hydraulic conductive fault systems present in the northern part of the Cheb Basin. Sharp falls in gas concentration, during or subsequent to, earthquake swarms may reflect fault compression associated with impeded gas migration. However, gas variations also occur in periods without seismic activity, indicating changes in fault permeability were caused by local aseismic fault movements, as revealed by events with opposite trends in the gas recordings at Oldřišská, Nový Kostel and the Soos. Therefore, a mathematical approach to establish a correlation between seismicity and gas geochemical variations is not possible.  相似文献   
62.
Between ca. 6000 BC and ca. 500 BC, barley cultivation spread across the continent of Europe from the extreme south to the extreme north. Carbon-dating would suggest that this spread, and indeed the spread of crop cultivation generally, varied in its pace, with ‘delays’ at certain points along its route. Such delays in the spread of agriculture have been explained as resulting from the slow assimilation of agricultural practices by existing indigenous human populations or as the time taken for the crops to adapt to novel climatic conditions, such as altered temperature regimes and day-lengths. A mutant form of the photoperiod response gene, Ppd-H1, causes barley to be non-responsive to long days, while the wild-type responsive form allows plants to flower in response to long days. We sequenced this gene in 65 ‘historic’ barley accessions, from the late 19th and early 20th centuries, in order to explore the potential role of environmental adaptation in the spread of agriculture. We chose to use ‘historic’ material, to complement the richer patterns in extant genetic lines, by spreading the data range in both time and space. Our ‘historic’ barley data shows a latitudinal divide in the Ppd-H1 gene similar to that found in extant lines, but with clearer geographical resolution, and extending northwards into the Arctic Circle. We discuss the implications of our results in relation to the dynamics of agricultural spread across Europe.  相似文献   
63.
罗福惠 《史学月刊》2005,1(4):33-38
19世纪末20世纪初,西方把中国人妖魔化的“黄祸”论甚嚣尘上。对此,在政治上和文化上都属保守主义者的辜鸿铭,用外文撰写了一系列文章加以批驳。辜文主要从中西文化的不同性格入手,论证中国文明是高度发达的文明,中国人是深具“理性意识和道义感”的民族,并以具体事例证明一些在华西方人的言行不符合文明人的标准。他还指出各自“扩展”,即实现“知识和道德意义上”的“门户开放”,是消除双方恐惧和敌意的根本办法。  相似文献   
64.
对汶川地震移民来说,社区人文社会环境直接影响他们的社会适应状况。本文基于调研数据,构建模型来探究社区人文社会环境对移民社会适应的影响。研究表明:社区人文社会环境下的16个单一指标,仅"社区治安"和"干群关系评价"对移民的社会适应状况有显著影响;但16个单一指标集成的4个综合指标-"配套设施"、"邻里关系"、"干群关系"和"观念习俗",却均对地震移民的社会适应状况影响显著,并且除"观念习俗"与移民的社会适应程度呈弱显著的负相关关系外,其他3个综合指标与移民的社会适应程度都呈强显著的正相关关系。  相似文献   
65.
为探索汶川地震作用下以浮放为主的可移动文物的震害及防震措施,通过震后勘查,讨论了汶川地震造成的可移动文物的典型震害症状。从博物馆、陈列台、文物本身等三个方面,分析了可移动文物的主要震害原因和传统的防震措施的不足之处,对国内外可移动文物的先进防震技术进行了探讨,研究了其防震机理。基于国内外可移动文物防震经验,对我国可移动文物提出了防震建议。研究结果表明:汶川地震造成可移动文物震害除了地震本身因素外,文物防震措施不足是一个重要原因;为保证可移动文物的防震性能,首先应规范博物馆建筑抗震设计,其次考虑陈列台隔震技术应用,最后再考虑可移动文物与陈列台之间的可靠连接;采取先进的隔震技术对可移动文物的防震具有促进作用。  相似文献   
66.
During earthquake emergencies in existing city-centers, streets network permits inhabitants to reach safe areas, and rescuers to access damaged zones and help population. However, the network can suffer from blocks due to debris of collapsed or heavily damaged buildings. Understanding urban fabric modifications and classifying elements vulnerability are fundamental steps while dealing with risk-assessment and risk-reduction strategies. This article offers a first quick approach for assessing seismic vulnerability of paths network by considering interferences with building heritage damages. Quick data about existing urban fabric (e.g., buildings typology; streets and buildings geometries) are combined for developing new vulnerability indices for streets network. The earthquake macroseismic intensity is introduced for evaluating probable street blockages and summarizing the overall rating of risks in critical network locations, thus intensity that is not included in other current quick methods for streets-building interference is here taken into account. Risk-reduction strategies based on the proposed indices could minimize the interventions on architectural heritage, maximizing the safety of evacuees. These new indices could be combined with traditional assessment of buildings vulnerability, and evaluations on pedestrians’ and vehicles evacuation flows, for evaluating management strategies.  相似文献   
67.
The delegation of decision‐making capacity from one actor to another—known variously as authority or control—is a central phenomenon of organizational sociology. Despite its theoretical and practical significance, however, the dynamics of control within disrupted settings (such as disasters) remain poorly understood. Here, we shed light on this question by a reexamination of historical data on multiorganizational disaster response networks, using recently developed statistical methods for robust inference from error‐prone informant reports. Specifically, we test competing hypotheses about the relationship of control during the response process to the structure of interorganizational communication. We find that both the realized and normative response hierarchies are likely shaped by coordination among both nonadjacent alters and along indirect channels. Our results suggested that the communication structure of these networks is consistent with a control at a distance model of command. This article makes a substantial contribution to understanding the role of network structure in the emergence of control between organizations in disrupted settings. Additionally, our innovative approach to network inference will guide researchers in dealing with error‐prone data in their own research on policy networks.  相似文献   
68.
In this article I analyse how a number of Italian, left-wing youth groups (centri sociali) reacted to the earthquake that struck the Emilia-Romagna region in 2012, forcing thousands of people to relocate into the tendopoli camps run by the Italian Civil Protection (Protezione Civile). The centri sociali promoted an alternative, grassroots project of emergency management which built both on a negative, collective memory of the problematic reconstruction process following the 2009 earthquake in L'Aquila, and on the role model of the No Tav protest movement in Piedmont. This led the centri sociali to move away from the urban territory and from the global battles that have long marked radical left-wing political activism, engaging instead in a more locally rooted project that clashes with the die-hard image of left-wing antagonism. Why have these groups taken their battle into the country side? Are we witnessing a (re)turn to a more local protest culture?  相似文献   
69.
This paper addresses the problem of the behaviour of underground tunnels subjected to longitudinal earthquake excitation. State-of-the-art solutions, which are relative to infinite length tunnels in the stationary case, with linear models for both the ground and the structure, are first recalled. These models are either static or dynamic; results generally indicate large strains, often incompatible with reinforced concrete structures, and small crack widths.

For finite length tunnels, in this study the dynamic solution for the linear case is developed and it is shown that maximum strain is an increasing function of the tunnel length so that, in many situations, the behavior of the lining is satisfactory also under the aspect of crack formation. When the nonlinear behaviors of the tunnel and soil are taken into account, segments of reinforced concrete tunnels, after cracking, may undergo considerable relative displacement, undesired both for serviceability and ultimate limit states. After review of the constitutive relationship for the ground, a parametric study on the crack openings for an example tunnel is presented. It is shown that crack widths computed with linear static analyses underestimate the real value for tunnels embedded in stiff grounds and that the lining longitudinal reinforcement can reduce crack width so as to cope with serviceability and ultimate limit states.  相似文献   
70.
Occasionally there is an earthquake in the UK during which church bells are reported to have been set ringing. The motion of a medium sized church bell has been simulated and the response to earthquake records from the Parkfield earthquake of 1966 has been calculated. The response of the bells is found to depend on the mechanical properties of the bell and the tower in which it is hung. The analyses do show that for a bell to ring in an earthquake the peak ground acceleration is in the range 0.97 to 29.4 m s?2 considerably in excess of the range indicated by the MMI VI “church and school bells ring” of 0.4 to 1.5 m s?2. The best correlation between recognised earthquake parameters and the ringing of the bell was obtained by combining the spectral values for clapper-bell angle, obtained from the linearised set of equations, at the bells natural frequencies using the SRSS method. The values of this parameter to set the bell ringing was in the range 0.25 and 0.38 rad, compared with the actual striking angle 0.54 rad.  相似文献   
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