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1.
蒙古共和国是一个内陆国,南临中国,北临俄罗斯。是世界上人口密度最低的国家之一,人口总数250万人,国土面积约为160万平方公里。总人口的30%居住在首都乌兰巴托,30%的人口居住在中部地区,西部地区的人口占总人口的18%,东部和南部地区人口稀少,占总人口的32%。尽管过去几年国家经济保持持续增长,但贫困问题在城市和乡村中依然是痼疾。2004年蒙古的经济增长率为10.6%,是1991年蒙古实行经济改革以来的最高增长率。国际市场上较高的矿产品价格以及2004年温和的气候成为蒙古国经济增长的积极因素。蒙古国年GDP约15亿美元,工业总产值占全国GDP…  相似文献   

2.
[目的]研究福建省雷暴活动特点和气候规律.[方法]利用1960~2007年福建省67个气象站的逐日雷暴资料,采用气候倾向率、趋势系数等方法,分析了福建省雷暴的时空分布特征.[结果]1960~2007年福建省的雷暴日数分布呈东北-西南走向,并从沿海向内陆逐渐递增.高值区在龙岩地区,沿海岛屿最少.48年福建省雷暴日数有明显减少的趋势,中部沿海地区减少速率为3.5 d/lOa,内陆山区大部分为4.5 d/10a,宁德北部、三明东部及南平部分地区为5.5 d/1Oa.雷暴日趋势系数变化有明显的区域特征,特别是内陆山区比沿海减少的趋势更加明显;减少最多的地方是南平地区的北部,趋势系数达-0.65;而中部沿海地区减少趋势不太明显,系数仅为-0.15a雷暴日有明显的季节变化,3~9月是雷暴的多发期,8月达最高值,9月开始迅速减少,从10月开始一直到次年2月都较少雷暴发生.平均初雷日西北部地区早于东南部地区,平均终雷日北部地区和南部地区差异不大.由于福建省北部和西部地区初雷日出现早,终雷日出现晚,造成全年雷暴活动时间比沿海长,两者相差近一个月:[结论]该研究为重大工程项目的气候可行性论证提供科学依据,为防雷减灾提供天气气候方面的理论依据,也对进一步研究福建雷暴的形成机理奠定基础.  相似文献   

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[目的]研究基于GIS的贵州省暴雨灾害风险区划.[方法]选取贵tM作为研究区域,以1 km×1 km栅格数据为评价单元,利用贵州省1961~2008年气象站点日降雨资料,从致灾因子危险性、承受体易损性、孕灾环境敏感性及防灾减灾能力4个方面构建暴雨灾害风险区划指标体系;在层次分析法确定影响因子权重的基础上,构建基于GIS的风险评价模型对4个子指标和风险性总指标分别评价,并最终得到贵州省暴雨灾害风险区划图.[结果]贵州省暴雨灾害风险自中部向四周呈递减的总趋势,低风险区集中在贵州省东北部,暴雨较少、抗灾能力较强是该区风险低的主要原因;高风险区集中在省中部偏西地区,主要因为暴雨集中、地形变化大、森林覆盖率低,其中安顺市较高以上风险地区占该市98.02%,而2010年发生特大地质灾害的贵州省安顺市关岭县岗乌镇也属于高风险区,这与实际受灾情况相吻合.[结论]该研究为以区域为对象的宏观防灾减灾规划提供理论依据.  相似文献   

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哈图金矿带是新疆最大的金矿集带,但其总体构造特征、成矿规律和找矿方向尚不明晰。为查明该矿带的总体构造特征,确定今后的找矿方向,从区分成矿期构造和成矿后构造的思路出发,对区内各主要断裂进行了详细的研究和分析。原认为属于所谓“成矿或控矿”断裂的哈图、安齐和达尔布特大断层均应属于成矿后断层,并截切、错移了相对早期形成的哈图金矿带,从而使其复杂化。而真正的“成矿构造”乃系一个走向NEE、倾向NNW,总体上呈上宽下窄的大楔状体。该楔状体被哈图、安齐大断层截断和错移,形成了一个走向NEE、倾向NNW的叠瓦状构造。在此基础上,提出今后的找矿方向:中部以齐Ⅰ矿区为中心,处于楔状体的中心部位,矿体厚度大品位高,找矿和采矿前景最好;南部达尔布特矿带(东部地区)处于楔状体最上部,矿脉呈分散的中小型,但数量较多,应以寻找中小型矿为主;北部哈图矿带处于楔状体的最下部,矿脉少、薄且贫,找矿前景最差。  相似文献   

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利用1960~2009年济南6测站雷暴观测资料,从雷暴日数年月分布和雷暴初终日变化趋势及初终日的绝对变率、相对变率等方面进行了分析,深入了解济南市雷暴发生的气候规律以及演变趋势.从年际变化来看,济南市雷暴日数整体呈减少趋势,济南站年平均雷暴日数在均值附近波动,其余各站年平均雷暴日数线性倾向率为-2.5~-3.9 d/10 a.雷暴只发生在3~11月,6~8月是雷暴多发期,7月雷暴最多,8月次之.中部山前平原较北部冲击平原和南部丘陵山区雷暴初日出现偏早,而雷暴终日结束偏晚,初终间日数延长;南部丘陵雷暴初日、终日均较平原区稳定.  相似文献   

6.
青海都兰阿拉克湖—红水川地区地质特征与找矿前景   总被引:1,自引:1,他引:0  
拉克湖—红水川地区的地质—构造—物化探资料表明:该区具有寻找铜(钴)金等矿床的良好的成矿背景,是东昆仑重要的成矿带。北部东昆仑南构造带的主攻矿种是Cu、Co、Au,其次是Pb、Zn、W,矿床类型为与华力西期基性—中基性海相火山岩有关的火山喷流沉积型SEDEX、VHMS型铜金钴矿、与中酸性侵入岩有关的矽卡岩型、热液脉型贵金属及多金属矿和叠加改造型矿床;中部重视洪冲积型、现代砂矿型砂金和膏盐矿床;南部主攻矿种为Cu、Co、Au,其次是Ni、Fe、Cr矿床类型为布青山群中与华力西期基性—中基性海相火山岩有关的块状硫化物型铜钴、铜金矿,伴有基性—超基性岩侵入的镁铁—超镁铁质岩浆熔离型的镍矿和结晶分异型的铬铁矿。  相似文献   

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兰州市位于甘肃省中部,东临定西市,南接临夏回族自治州,西与青海省毗邻,北靠武威市和白银市,是甘肃省政治、经济、文化和商贸中心,也是西北地区的交通枢纽和旅客集散地.现辖城关区、七里河区、安宁区、西固区、红固区五区及皋兰、榆中、永登三县,市域总面积1.31万km2,其中市区面积1631.6km2,全市总人口326万人,其中市区人口207万人,平均人口密度1196人/km2.兰州市地处青藏高原、黄土高原和内蒙古高原的交汇地带,新构造运动强烈、地形起伏、沟壑纵横、谷深坡陡、黄土广布,气候干燥、降水集中、植被稀少,加之人口稠密、人类工程活动强烈,使得滑坡、泥石流等地质灾害非常活跃,是我国滑坡、泥石流灾害最为严重的省会城市之一.随着人类工程活动的不断升级加剧,其引发地质灾害的可能性也在不断增大,地质灾害在区内呈现高发趋势.值得一提的是,区内一些原本不易发生地质灾害的沟谷、斜坡受人为因素影响已发展成为新的地质灾害隐患点,且有愈演愈烈之势.  相似文献   

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在中国社会大发展的当下,因为以汉族为主要民族成分的广大东部地带在经济、文化、教育等各个领域已经成为如今中国的经济社会发展最发达也是发展最快的地区,但是,与此同时,那些集中于西南,相对偏远地区的凉山彝族则处于相对落后的状态。加上当地群众大量外出务工,很大程度上改变了自己的物质与精神生活,造成了凉山彝族文化在很大程度上被外民族化,自身的特色正在不断消解。而凉山彝族传统舞蹈也面临着这样的问题,在这种背景下,很有必要对现在的彝族传统文化的发展状况做个梳理,并对如何保护给予相当的重视,迫切地需要从各个方面做好保护工  相似文献   

9.
转炉炉壳热应力分析   总被引:5,自引:1,他引:4  
任学平  郭志强  邹家祥 《炼钢》2001,17(6):47-49
根据实际转炉建立实体模型。以有限元为手段,考虑了炉衬和炉壳材料的物性参数随温度变化的特点和炉衬与炉壳之间膨胀间隙,计算了转炉炉壳在温度载荷和炉衬膨胀压力同时作用下的热应力。所得结果可为转炉炉壳设计提供依据。  相似文献   

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通过对焦炭在高炉内的历程及其变化规律的剖析,阐述焦炭热性能指标的意义,形象地把焦炭在高炉内的损耗分为三部分(M1,M2,M3)。指出M2对焦比及焦炭价格有一定的指导作用。  相似文献   

12.
Cancer of the cardia is traditionally discussed with cardiac cancer of the lower portion of the esophagus and upper gastric cancer invading the esophagus, and the specific characteristics of cancer of the cardia have never been clearly defined. We reviewed the outcome of 172 patients with adenocarcinoma of the cardia who had undergone radical surgery between 1949 and 1994 in the Division of Gastrointestinal Surgery of the Cancer Institute Hospital. The centers of the tumors were located within 2 cm above and below the boundary between the esophagus and the stomach, and their longitudinal diameter was less than 8 cm. We divided the patients into an early period (1949-1979; n = 79) and a late period (1980-1994; n = 93), and focused on the historical transition. There were no differences in patient gender or histology between the two periods. However, the late period was associated with fewer cases of esophageal invasion and shorter longitudinal diameter, as the age of the population advanced. The number of advanced cancers such as the localized and infiltrative type had decreased, and early cancer and early clinical stage had become more common, but despite the fact that the number of early cancers had increased, extended dissection, such as thoracic and paraaortic lymph node dissection, was performed more frequently. By clinical stage, the long-term outcome markedly improved in Stage I patient in the late period, and tended to improve in Stage II and III patients. This appears to have been attributable to the prevention of micrometastasis by extended dissection, although the number of early cancers is another major potential cause. There were no differences in the outcome of Stage IV patients between the two periods, and further advances in multimodality therapy must be awaited. The range of resection is basically proximal gastrectomy, and if there are adequate indications, the prognosis is favorable. In view of the status of lymphatic flow and lymph node metastasis, and long-term results, lateroaortic lymph node dissection is important. Since the number of early cancer patients has been increasing, if intraabdominal recurrence is prevented, intrathoracic lymph node dissection will contribute greatly to the outcome of such patients.  相似文献   

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Some theories of personality hold that an individual's perception of others is influenced by his own personality characteristics; more specifically, that a trait of low social value will be projected more into others, and that insight into the possession of these characteristics reduces this distortion. These 2 hypotheses were tested by having a group of college students rate each other (including themselves) on degree of friendliness or hostility. Agreement with group rating about self yielded the insight score. In general, the hypotheses were supported; the "friendly" Ss were most accurate in their perception of others, and insight was positively associated with accurate perception. From Psyc Abstracts 36:04:4HL16M. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   

15.
The effect of 20 different antibiotics on chemotaxis by human neutrophils was studied. Human leukocytes incubated with chloramphenicol, rifampin, sodium fusidate, and tetracyclines in vitro showed markedly depressed migration. The mechanisms by which these antibiotics affect leukotaxis are discussed.  相似文献   

16.
Usage of quality of life of psychiatric patients' relatives as the parameter of estimation of the quality of psychiatric care is considered. By means of standard questionnaire elaborated by the authors as well as by means of both individual and group conversations the quality of life was analyzed in 40 relatives which lived together with psychiatric patients. Different spheres of their life and difficulties (financial, social-psychologic, production) were examined in families with such patients. The defects of psychiatric care that had direct influence on the quality of life of the psychiatric patients' relatives are outlined.  相似文献   

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