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41.
Journal of Oceanology and Limnology - Salt stress is an abiotic stress to plants in especially saline lakes. Dunaliella, a halophilic microalga distributed throughout salt lakes and seas, can... 相似文献
42.
Journal of Oceanology and Limnology - Polycyclic aromatic hydrocarbons (PAHs) are one of the most important groups in oil, and responsible for major toxic and/or carcinogenic impact on humans and... 相似文献
43.
为真实了解天津市公众地震科普认知与需求情况,以天津市机关单位工作人员、企业员工、事业单位工作人员、大学生、中小学生、社区居民、农民、驻津部队、残障人士等特殊人群为研究对象,开展专项问卷调查与分析。调查结果显示,天津市公众地震科学知识与地震科普工作的认知度与需求度较高,但仍存在地震科学知识掌握不全面、地震科普产品吸引力不足、科普渠道相对单一等问题,地震科普工作在参与性、互动性与趣味性等方面仍有较大提升空间。基于此,提出提高地震科普工作针对性和有效性及地震科普服务个性化和精准化等建议。 相似文献
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45.
This paper presents a method of establishing a hydrothermal ore-forming reaction system.On the basis of the study of four typical hydrothermal deposits,the following conclusions concerning geochemical dynamic controlling during hydrothermal mineralization have been sions concerning geochemical dynaamic controlling during hydrothermal mineralization have been drawn:(1)The regional tectonic activities control the concentration and dispersion of elements in the ore-forming process in terms of their effects on the thermodynamic nature and conditions of the ore-forming reaction system.(2)During hydrothermal mineralization the activites of ore-bearing faults can be divideb into two stages:the brittle splitting stage and the brittle-tough tensing stage,which would create characteristically different geodynamic conditions for the geochemical thermodynamic ore-forming system.(3)The hydrothermal ore-forming reaaction system is an open dynamic system.At the brittle splitting stage the system was so strongly supersaturated and unequilibrated as to speed up and enhance the crystallization and differentiation of ore-forming fluids.And at the brittle-tough tensing stage,the ore-forming system was in a weak supersaturated state;with decreasing temperature and pressure the crystallization of oreforming material would show down,and it can be regarded as an equilibrated state.(4)In the lates stages of hydrothermal evolution,gold would be concentrated in the residual ore-forming solution.The pulsating fracture activite in this stage led to the crush of pyrite ore and it was then filled with gold-enriched solution,forming high-grage“fissure”gold ore.This ore-forming process could be called the coupling mechanism of ore formation. 相似文献
46.
LUO Jia NING Jinsheng LUO Zhicai 《地球空间信息科学学报》2005,8(3):205-208,219
Satellite-to-Satellite Tracking in low-low model (SST-Ⅱ) is a new technique to resolve the series of problems met in the determination of the earth's gravity field. As the key technique of SST-Ⅱ, KBR can get SST-Ⅱ measurements directly. So the KBR performance analysis is the first step in SST-Ⅱ design. In this paper, assuming that the satellite pairs of SST-Ⅱ are in near circle polar orbits, the spectrum relationship between the earth gravity field and KBR is established using analytic method. And then some examples are analyzed, the suggestions and conclusions are drawn from these examples. The research results could be taken as a reference for future satellite gravity project of China. 相似文献
47.
美术与感觉寻求的关系 总被引:1,自引:0,他引:1
阐述了感觉寻求研究中与绘画有关的研究,分析感觉寻求人格与绘画的复杂度、风格倾向、内容的积极性以及艺术的不确定性之间的关系,认为美术学习可能会影响到人格的发展趋势,影响其创造性人格特质的形成。 相似文献
48.
基于生态系统服务价值评估的我国集中连片重点贫困区生态补偿研究 总被引:1,自引:0,他引:1
本文基于2010年Landsat TM/ETM+数据,HJ-1卫星CCD数据,MODIS17A3净初级生产力数据和土壤,气候的地面实测数据,采用以生态系统服务价值为基础的区域差异化生态补偿估算方法,对中国14个集中连片贫困区生态补偿标准进行了估算.研究结果表明,2010年中国14个集中连片贫困区生态系统服务总价值达20 627.4亿元,与同年该区域GDP总量 22 096.2亿元大体相当,在南疆三地州,四省藏区和西藏片区3个西部片区,每年的生态系统服务总价值为GDP总量的2-12倍,这对保障中国生态安全具有重要意义.在14个集中连片特困区,生态补偿所需资金每年约为1971.0亿元,平均每县约为2.9亿元.目前,国家给予的生态补偿资金与此相比严重不足,即使是接受一般性财政转移支付的国家重点生态功能区,其各县市平均每年接受补偿资金也仅为0.94亿元,不到所需金额的1/3.生态补偿资金不足不但给各片区扶贫工作带来巨大压力,也带来了严重的生态风险.因此,生态补偿资金增量的投入可能是解决集中连片特困区贫困问题关键所在,在此增量补偿资金基础上,集中连片特困区可建立以国家购买生态产品为主,开发性扶贫增长为辅的可持续经济增长模式,这可能是彻底解决中国集中连片特困地区贫困问题的基本途径. 相似文献
49.
Wen-xiong Jia 《山地科学学报》2016,13(12):2224-2236
Based on daily maximum and minimum temperatures at 18 meteorological stations in the Qilian Mountains and Hexi Corridor between 1960 and 2013, temporal and spatial variations in extreme temperatures were analysed using linear trends, ten-point moving averages and the Mann-Kendall test. The results are as follows: The trends in the majority of the extreme temperature indices were statistically significant, and the changes in the extreme temperatures were more obvious than the changes in the extreme values. The trends were different for each season, and the changes in rates and intensities in summer and autumn were larger than those in spring and winter. Unlike the cold indices, the magnitudes and trends of the changes in the warm indices were larger and more significant in the Hexi Corridor than in the Qilian Mountains. Abrupt changes were detected in the majority of the extreme temperature indices, and the extreme cold indices usually occurred earlier than the changes in the extreme warm indices. The abrupt changes in the extreme temperatures in winter were the earliest among the four seasons, indicating that these temperature changes were the most sensitive to global climate change. The timing of the abrupt changes in certain indices was consistent throughout the study area, but the changes in the cold indices in the Hexi Corridor occurred approximately four years before those in the Qilian Mountains. Similarly, the changes in the warm indices in the western Hexi Corridor preceded those of the other regions. 相似文献
50.
本文在阐述由DLG、DRG、DEM和DOM组成的4D产品的信息特征的基础上,深入分析了"4D"数据在生态环境监测与评价中的功能,包括生态环境的快速动态监测、三维生态景观的直观分析和表达、DLM与DCM相结合的生态模拟、多时空尺度的生态环境分析与评价等.并以云南省生态环境监测与评价为例,研究了其在生态环境监测与评价中的技术流程,并通过案例分析,生成了系列生态环境地图. 相似文献