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31.
土地市场动态监测与监管关乎国计民生,土地市场信息发布是国土资源部门户网站服务社会公众的重要功能。本文从土地市场信息整合需求分析入手,详细介绍了国土资源部门户网站内容整合规划、信息分类整合和页面集成策略,并以实际成效证明了土地市场信息整合是国土资源部门户网站推动国土资源信息社会化服务的一次成功实践。  相似文献   
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孟莉  刘岩  谭小月 《吉林气象》2015,(2):23-27,65
学业评价是教师教育教学中的重要环节,不仅关系到对学生的评价,也关系到学生对学习的情感态度和努力投入,以及师生关系的质量。优秀的中小学教师在评定学生学业成绩时,能够从学生长远发展角度考虑评价对学生的全面影响,重视评分的发展性评价目的;在具体评分实践中,能充分考虑学生对分数的认识、理解和感受,评分目的明确;能够运用多种评价方式,从多个来源对学生多个方面的表现实施多元综合评价;能够根据评分目的和条件合理恰当地选择评分标准,评分灵活可靠,又不失评价原则。这些理念和策略作法,确保了他们的评分能够真正发挥鼓励学生学习,促进学生成长的广阔而深远的目的。  相似文献   
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The distribution and abundance of euphausiid larvae and salps was studied from samples collected in 2002 and 2006 from Prydz Bay, Antarctica.Larvae of Thysanoessa macrura and Euphausia superba were mainly distributed in the north of the continental shelf. T. macrura was more abundant and had a relatively wider distribution. In 2006, with ice having retreated and higher seawater temperatures and chlorophyll a levels, E. superba and T. macrura occurred in higher abundances and at more mature developmental stages. Euphausia crystallorophias was mainly distributed in the neritic region. In 2002, with severe ice conditions in the neritic region, abundance of E. crystallorophias was consisted of metanauplius (MN) and calyptopis I (CI). Salps, mostly Salpa thompsoni, had a low abundance in Prydz Bay. In 2002, S. thompsoni was only m)-3. In 2006, S. thompsoni was found at three stations located near the contimental factors, such as the timing of ice melt, polynya formation and food concentration appear to have a marked effect on the distribution and abundance of euphausiid larvae and salps.  相似文献   
35.
The hafnium isotopic analysis using laser ablation has been widely conducted on Hf-rich minerals(zircon/baddeleyite/ calzirtite/eudialyte), however, little work has been reported on Hf-poor(100 ppm) minerals. This work presents a detailed procedure of in situ hafnium isotopic analysis from rutile using laser ablation multiple collector inductively coupled plasma mass spectrometry(LA-MC-ICP-MS). The rutile U-Pb dating reference material JDX shows homogeneous hafnium isotopic ratios, with 176Hf/177Hf=0.281795±0.000015(2SD, n=33) and 176Lu/177Hf=0.000018±0.000004(2SD, n=17) that suggest the possibility of using JDX as a new reference material hafnium isotopic measurement. We also measure hafnium isotopic compositions of other rutile U-Pb dating reference material(R10, Sugluk-4 and PCA-S207) and the 176Hf/177 Hf values are similar to previously reported results, which confirms that we can acquire accurate and precise hafnium isotopic compositions using our developed analytical protocol. We analyzed hafnium isotopic compositions and U-Pb ages of rutile in high-temperature and ultrahigh-temperature granulites from various terrains of the Khondalite Belt from the North China Craton, combined with zircon results in the same area, suggesting that the metamorphic evolution history of the granulite is much more complicated than previously thought.  相似文献   
36.
Li  Weidong  Deng  Lijun 《Acta Geotechnica》2019,14(2):461-475
Acta Geotechnica - Small-diameter helical piles have been increasingly used in Western Canada, but there is a lack of research. The present research investigates the axial behavior of three types...  相似文献   
37.
Huang  Qingyu  Wang  Jun  Li  Mengya  Fei  Moli  Dong  Jungang 《Natural Hazards》2017,87(2):1035-1055
Natural Hazards - Rapid urbanization has brought great productivity, prosperity and challenges to Shanghai in the last few decades. This paper focuses on the influence of urbanization on urban...  相似文献   
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We evaluated tools and methods for in situ freezing of cores in unconsolidated subsurface media. Our approach, referred to as cryogenic core collection (C3), has key aspects that include downhole circulation of liquid nitrogen (LN) via a cooling system, strategic use of thermal insulation to focus cooling into the core, and controlling LN back pressure to optimize cooling. Two cooling systems (copper coil and dual‐wall cylinder) are described. For both systems, the time to freeze a single 2.5‐foot (76‐cm) long by 2.5‐inch (63‐mm) diameter core is 5 to 7 min. Frozen core collection rates of about 30 feet/day (10 m/day) were achieved at two field sites, one impacted by petroleum‐based light nonaqueous phase liquids (LNAPLs) and the other by chlorinated solvents. Merits of C3 include (1) improved core recovery, (2) potential control of flowing sand, and (3) improved preservation of critical sediment attributes. Development of the C3 method creates novel opportunities to characterize sediment with respect to physical, chemical, and biological properties. For example, we were able to resolve water, LNAPL, and gas saturations above and below the water table. By eliminating drainage of water, gas and LNAPL saturations in the range of 6 to 23% and 1 to 3% of pore space, respectively, were measured in LNAPL‐impacted intervals below the water table.  相似文献   
40.
Ray Riley  Maria Tkocz 《GeoJournal》1999,48(4):279-290
It is argued that the emphasis of much recent research into coalmining has been placed on international and national scale influences which affect coalfields as a whole; change at the intra-coalfield scale has received less attention. After providing a background to events in Poland during communism, attention focuses on developments since 1989, commencing with coalfield-wide influences. There follows an examination of the work of the state body Państwowa Agencja Węgla Kamiennego, which executes government policy at the local level, and whose membership is drawn from the coalfield region. This agency recommends the closure and amalgamation of mines, but otherwise rationalisation measures are left to the seven mining companies and the colliery managers. The restructuring which has been carried out is considered under five heads: organisational change within the collieries, employment, production and technical change, and ecological adjustment. While recognising the importance of the socioeconomic and political environment and geology, there is much evidence to suggest that intra-coalfield patterns are strongly determined by local decision-makers. This revised version was published online in July 2006 with corrections to the Cover Date.  相似文献   
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