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21.
永历王朝在明清易代之际播迁于粤、桂、湘、黔、滇和缅甸等地,期间与农民军余部进行合作,建立抗清统一战线,但是在坚持了15年之后终告失败,本文试着从其内政的腐败以及与农民军合作的困难重重探寻失败的缘由。  相似文献   
22.
江西省农业院是1934年3月设立的一个全省性的农业技术改进和推广机构,在其存在的15年历史中,从许多方面对江西农业现代化进行了卓有成效的探索,做出了巨大的贡献。但由于缺乏相应的社会条件作支撑,其推进农业现代化的种种努力最终逃脱不了失败的命运。  相似文献   
23.
Reports of congenital scoliosis (CS) are rare in the literature of paleopathology. This study details severe CS in the complete, well preserved skeleton of an adult male, dated to AD 550–800, from the Sudanese site of Kulubnarti. This skeleton, designated as S‐16, is the most complete archaeologically derived example of CS to be documented. Copyright © 2009 John Wiley & Sons, Ltd.  相似文献   
24.
Geological storage of CO2 in depleted oil and gas reservoirs is one of the most promising options to reduce atmospheric CO2 concentrations. Of great importance to CO2 mitigation strategies is maintaining caprock integrity. Worldwide many current injection sites and potential storage sites are overlain by anhydrite‐bearing seal formations. However, little is known about the magnitude of the permeability change accompanying dilatation and failure of anhydrite under reservoir conditions. To this extent, we have performed triaxial compression experiments together with argon gas permeability measurements on Zechstein anhydrite, which caps many potential CO2 storage sites in the Netherlands. Our experiments were performed at room temperature at confining pressures of 3.5–25 MPa. We observed a transition from brittle to semi‐brittle behaviour over the experimental range, and peak strength could be described by a Mogi‐type failure envelope. Dynamic permeability measurements showed a change from ‘impermeable’ (<10?21 m2) to permeable (10?16 to 10?19 m2) as a result of mechanical damage. The onset of measurable permeability was associated with an increase in the rate of dilatation at low pressures (3.5–5 MPa), and with the turning point from compaction to dilatation in the volumetric versus axial strain curve at higher pressures (10–25 MPa). Sample permeability was largely controlled by the permeability of the shear faults developed. Static, postfailure permeability decreased with increasing effective mean stress. Our results demonstrated that caprock integrity will not be compromised by mechanical damage and permeability development. Geofluids (2010) 10 , 369–387  相似文献   
25.
近年来,随着语际语用学(interlanguage pragmatics)的兴起,语言迁移问题备受人们的关注,其中母语的负迁移更是跨文化和二语习得领域内学者们关注的一个重点问题,本文拟从语用迁移中的语用语言迁移和社交语用迁移的两个层面,以跨文化交际中的实例来探讨母语语用负迁移对跨文化交际中的语用失误的影响作用。  相似文献   
26.
近年来阿房宫考古发掘表明,秦始皇与秦二世在位时兴建的阿房宫是没有建成的“半拉子”工程,而且阿房宫遗址中未发现火烧的遗迹,这与《史记》中“阿房宫未成”的记载是相一致的,即阿房宫没有建成。秦代两度修建阿房宫之所以未成,其原因主要是由于工程规模庞大,所需的土、木、石建筑材料需要大批人力去采集、运输和加工,加之施工人力不足、修建工期短,导致秦代两度修建阿房宫均以“未成”而告终。  相似文献   
27.
A ‘sense of failure’? Everydayness and research ethics   总被引:1,自引:0,他引:1  
A key legacy of much recent theorising in Anglo-American Human Geography has been the realisation that the ‘excess’ and ‘messiness’ of (too-easily and too-often overlooked) everyday events, geographies and experiences ought to have far-reaching conceptual and methodological implications. The aim of this paper is to elaborate some (as yet relatively implicit) ethical dimensions of this challenge, via a consideration of one particular notion and domain of ethics (research ethics in Human Geography) and, then, via one specific case study (re-presenting moments from my experiences of – and small ‘failures’ in – conducting qualitative research with children, as an adult male, in the UK, in 2000–2002).  相似文献   
28.
传统观点认为刘备夷陵之战失败,原因在于"备不知兵"。本文认为,夷陵之败,并非"备不知兵",而是有其客观原因和主观原因。客观原因为刘备兵力本不占优势,加之手下缺乏得力将才,后勤供应困难,以及水军力量薄弱。主观原因则为,刘备未做好充分准备,贸然出兵;初期的军事胜利,使其产生了骄傲轻敌情绪;对形势认识不足,缺乏战略考量,卒为敌所乘。  相似文献   
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30.
126 postglacial catastrophic rock-slope failures (PRSFs) and 66 debris-free failure scarps (DFFSs) were identified using Google Earth? imagery on Lewisian Gneiss (LG), Torridon Sandstone (TS), Cambrian Quartzite (CQ) and Moine Schist (MS) terrains in NW Scotland. Normalisation of these data for area and gradient shows that RSF density on slopes ≥25° decreases in the sequence MS?>?LG?≈?CQ?>?TS. Most are apparently discordant with structure, suggesting that failure along slope-(sub)parallel joints was more common than failure along bedding or foliation planes. DFFSs represent failure scars from which runout debris has been removed by later glaciation. Eighteen were recorded outside the limits of the Loch Lomond Readvance, implying that they survived the last ice-sheet glaciation, and support the view that many steep upper rock slopes have been dominated by gravity-driven rock detachment rather than glacial erosion. We argue that many RSFs were probably triggered by Lateglacial earthquakes due to fault (re)activation by crustal rebound, as 74% of recorded PRSFs and DFFSs are located at or near slope crests. 44% of recorded PRSFs and DFFSs occur in cirques, suggesting that cirque enlargement during successive glacial-interglacial cycles involved deepening by glacial erosion, headwall retreat by rock-slope failure and removal of RSF debris during subsequent glaciation.  相似文献   
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