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1.
CT引导下肝脓肿穿刺治疗   总被引:1,自引:1,他引:1  
本文报告了在CT引导下,对8例肝脓肿病人实施穿刺,吸脓,冲洗,埋管引流的方法与疗效探讨。8例患者均经过B超或CT诊断,用5F套管针穿刺,吸脓,冲洗,埋管,在临床配合下,病人症状缓解快,脓腔缩小,此法缩短治疗时间,它操作简单,易行,值得推广。  相似文献   

2.
杨文 《高原地震》2007,19(1):48-50
0 前言 临汾市位于山西省西南部,黄河中游,全市面积20275km^2,是山西地震带最重要的组成部分,地质构造十分复杂,地震断裂纵横交叉,为历史强震区。1996年以来,临汾市一直被国家确定为重点监视防御区,地震形势严峻,因此,防震减灾工作显得尤为重要。自2001年以来,临汾市防震减灾工作以邓小平理论和“三个代表”重要思想为指导,坚持以人为本,坚持科学发展观,  相似文献   

3.
地磁台站和地磁台网的现代化技术专辑   总被引:2,自引:0,他引:2  
地磁观测资料在地磁学,空间物理学,固体地球物理学及其它相关领域的研究和应用中具有十分重要的作用,资料质量对研究工作有重要影响,台网资料对研究工作有特殊意义,根据作者近年来学习、研究和实践的结果,本文第一部分从系统设计的角度就地磁台站现代化中的系统组成,功能,仪器和主要技术指标,台网建设,资料质量等问题进行了讨论,本文的第二部分介绍了世界地磁台网,包括INTERMAGNET的目标,历史,现状,原则,  相似文献   

4.
雄关漫道真如铁——论中国油气二次创业   总被引:17,自引:19,他引:17  
半个多世纪以来,中国经历了油气资源的第一次创业,在祖国大陆和近海大陆架地区的新生代陆相碎屑岩沉积盆地中,发现了一批油气田,使原油年产量达1.67亿吨,位居世界第五,天然气疸这241亿立方米,居世界第十五位,成绩是巨大的,但是,1993年开始进口原油3000万吨,2000年进口原油7200万吨,严重影响国家经济建设,而且这种趋势还在不断发展,预测2010年将进口原油1亿吨,天然气200亿立方米,那么,中国油气资源的出路何在?作者指出,从中国大地构造演化来看,前新生代海相残留盆地还有巨大的油气潜力,尽管其勘探的难度是世界级的,但是,只要我们切实地依靠科学技术,进行油气资源的二次创业,困难上,在实践中克服困难,就可以发现更多的石油天然气,支持国家经济建设的持续发展。  相似文献   

5.
动态监测方法在理论上是可行的,方法也是简便的,有着广阔的发展前景,但是,由于结构的复杂性,测量技术的局限性,单纯依赖理论计算分析诊断结构的病害状况并不总是容易实现的,本文介绍一种依据基本振型的振动反应求局刚度的方法,简单,实用,实践中如果辅以调查,考察,类比,分析...,可作出更切合实际的可靠诊断,文中还介绍一些实例,有助于启迪,开拓动态监测的应用领域。  相似文献   

6.
应用灰色系统理论,根据江苏省地震工程研究院的地震科技开发资料,分别以项目负责人的年龄,学历,职称,职务,学科作为比较数列,对年度内完成的实际合同额进行了多因素灰色关联分析,排出了关联序。研究结果客观地揭示了开发能力与人的各种因素-年龄,学历,职称,职务,学科之间的相互关系,为市场经济条件下,地震科技人才的开发,培养和应用。,提供了科学依据。  相似文献   

7.
动态应力触发的余震   总被引:1,自引:0,他引:1  
通常认为断层永久位移产生的小“静态”应力变化可以改变附近断层上发生地震的可能性或者说可触发地震(Harris,1998)。许多近场的触发地震,特别是触发余震的研究(Dieterich,1994;Toda,et al,1998;King,et al,1994),将这种静态变化视为触发因素,并认为它与断层上负载的变化是等价的(Toda,et al,1998;King,et al,1994;Jaume and sykes,1992;Harris and Simpson,1992)。这里我们报道矩震级Mw=7.3的兰德斯地震的余震图象与应力变化的比较,不仅与静态应力做对比,而且与地震波传递的瞬态、振荡应力变化(即,“动态”应力)做对比。动态应力不会永久地改变加载情况,仅能通过改变断层区的力学状态或性质来触发地震。这些被动态弱化的断层在地震波通过后可能破裂,甚至能导致如果没有动态应力就不会发生的地震。我们发现余震和动态应力图象都具有类似的不对称性,动态应力来自于破裂的传播,而静态应力变化没有这种不对称性。先前的研究表明,动态应力在远距离处可促使破裂(Anderson,et al,1994;Gomberg and Bodin,1994;Gomberg,1996;Gomberg and Davis,1996;Hill,et al,1993,1995),然而本文表明在近处也是如此。  相似文献   

8.
城市活断层探测中的浅层地震勘探方法   总被引:7,自引:0,他引:7  
对大量地震灾害的研究表明,地震发生时,位于地表活动断层上的房屋或构筑物的破坏最严重,尤其是20世纪90年代后期美国北岭地震,日本阪神地震和中国台湾集集大地震等的发生后,世界许多国家的政府和地震科学家都清楚地认识到城市活断层探测与研究的重要性和急迫性,城市活断层的探测对于城市规划,抗震设防,减轻地震对城市设施的破坏都具有重要的现实意义,浅层高分辨地震勘探是城市活断层探测手段中最有效,最可靠的方法之一,可以在地表探测到地下活断层的位置,埋深,产状和空间展布情况,但由于城市环境的强干扰背景和场地条件的复杂性,必须针对实际情况,在观测系统,震源,数据采集环境的强干扰背景和场地条件的复杂性,必须针对实际 情况,在观测系统,震源,数据采集和处理方法等环节中,采用一系列提高分辨率, 提高信噪比的有效方法,才能取得可靠的探测成果,本文对城市活断层探测中的浅层地震勘探方法的技术难点和相应的解决方法进行了讨论,并结合我们近几年来在城市开展浅层地震勘探的一些经验,介绍一些实用性的浅层地震勘探工作方法。  相似文献   

9.
两个最常引述的地震前兆指标是氡放射和电势变化(Wakita,Nakamura and Sano,1988;Igarashi,et al,1995;Virk and Singh,1994;Raleigh,et al,1997;Corwin and Morrison,197;Vaqrotsos,et al,1993),但已有的少量报道一般被认为是值得怀疑的(Geller,1996;Pham et al  相似文献   

10.
中国是海洋大国,海域划界是主权之争,主权的背后是资源的问题.摸清家底,才能在国际事务中争取主动,才能为国家的经济建设服务.因此,提出“丈量海洋国土,维护国家主权;调查海洋资源,合理利用海洋;保护生态环境,防治地质灾害”的主张.只有坚持科学发展观,利用最新的科学技术,统筹规划海洋事业,合理地开发、利用和保护海洋,才能实现中国海的可持续发展和协调发展.  相似文献   

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13.
《国际泥沙研究》2014,(4):F0003-F0003
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14.
《国际泥沙研究》2014,(2):F0003-F0003
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15.
《国际泥沙研究》2014,(3):F0003-F0003
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17.
The partitioning of rain water into throughfall, stemflow and interception loss when passing through plant canopies depends on properties of the respective plant species, such as leaf area and branch angles. In heterogeneous vegetation, such as tropical forest or polycultural systems, the presence of different plant species may consequently result in a mosaic of situations with respect to quantity and quality of water inputs into the soil. As these processes influence not only the water availability for the plants, but also water infiltration and nutrient leaching, the understanding of plant effects on the repartitioning of rain water may help in the optimization of land use systems and management practices. We measured throughfall and stemflow in a perennial polyculture (multi‐strata agroforestry), monocultures of peach palm (Bactris gasipaes) for fruit and for palmito, a monoculture of cupuaçu (Theobroma grandiflorum), spontaneous fallow and primary forest during one year in central Amazonia, Brazil. The effect on rain water partitioning was measured separately for four useful tree species in the polyculture and for two tree species in the primary forest. Throughfall at two stem distances, and stemflow, differed significantly between tree species, resulting in pronounced spatial patterns of water input into the soil in the polyculture system. For two tree species, peach palm for fruit (Bactris gasipaes) and Brazil nut trees (Bertholletia excelsa), the water input into the soil near the stem was significantly higher than the open‐area rainfall. This could lead to increased nutrient leaching when fertilizer is applied close to the stem of these trees. In the primary forest, such spatial patterns could also be detected, with significantly higher water input near a palm (Oenocarpus bacaba) than near a dicotyledonous tree species (Eschweilera sp.). Interception losses were 6·4% in the polyculture, 13·9 and 12·3% in the peach palm monocultures for fruit and for palmito, respectively, 0·5% in the cupuaçu monoculture and 3·1% in the fallow. With more than 20% of the open‐area rainfall, the highest stemflow contributions to the water input into the soil were measured in the palm monocultures and in the fallow. Copyright © 1999 John Wiley & Sons, Ltd.  相似文献   

18.
A procedure for short-term rainfall forecasting in real-time is developed and a study of the role of sampling on forecast ability is conducted. Ground level rainfall fields are forecasted using a stochastic space-time rainfall model in state-space form. Updating of the rainfall field in real-time is accomplished using a distributed parameter Kalman filter to optimally combine measurement information and forecast model estimates. The influence of sampling density on forecast accuracy is evaluated using a series of a simulated rainfall events generated with the same stochastic rainfall model. Sampling was conducted at five different network spatial densities. The results quantify the influence of sampling network density on real-time rainfall field forecasting. Statistical analyses of the rainfall field residuals illustrate improvement in one hour lead time forecasts at higher measurement densities.  相似文献   

19.
Red tide, a recurrent phenomenon has become conspicuous in several Kashmir lake ecosystems since 1991. The responsible organism (Euglena pedunculata), a rare flagellate rediscovered in the Kashmir Himalaya (Khan 1993) caused first and unprecedented red tide outbreak, constituting a maximum of 96% of resident numerical phytoplankton density in Dal Lake. At present, conflicting hypotheses exist on the generation of causal assemblage(s) imparting redness to waters: Jeeji Bai (1991) linked its origin to acid precipitation – a fallout of burning oil‐fields during the Gulf War – whilst Khan (1993) holds local factor(s) responsible. Field/experimental studies support the latter contention that the influx of untreated sewage, in unison with warm temperatures, high levels of PhAR, iron and interruption to hydrological flow‐pattern together with absence/or reduction in grazing activity created conducive environmental milieu for red tide outbreak. Dal Lake “red tide” drifted the bloom‐inoculum to other waters, including Lake Wular, where additional ecological niches were carved out, threatening the aesthetic value and biological diversity of Kashmir lakes. Ecological monitoring indicates frequent seasonal red tide occurrence in Dal Lake (including summer‐autumn event of 1998) which testifies its unabated eutrophication status. Further studies are needed on ecological adaptability and biogeographic distribution of this rare and unique red tide‐causing flagellate.  相似文献   

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