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从学生角度设计并实施了高校课堂教学质量满意度问卷调查,形成多级满意度评价指标,结合问卷所获得数据,通过构建Logistic模型,从学生和教师两方面探讨了影响高校课堂教学质量的主要因素.结论显示,学生学习态度、所在年级和授课教师专业水平和素质对高校课堂教学质量满意度有显著影响. 相似文献
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云南贡山8.18特大泥石流成因及其对矿产资源开发的危害 总被引：2，自引：0，他引：2
2010年8月18日云南省贡山县普拉底乡东月各沟暴发泥石流,造成了严重的人员伤亡和财产损失,是近年来发生于我国滇西北三江成矿带最严重的特大泥石流事件,同时也是泥石流危害矿产资源开发和利用的典型案例,分析其成因与防灾对策对未来该区域的发展规划,矿产资源的开发和利用,以及防灾减灾对策的制定具有重要的参考价值和警示意义。根据实地调查,结合遥感影像与气候资料分析,研究区的活动断层与1950年西藏察隅地震对东月各沟造成了严重影响,形成区的寒冻风化与第四纪冰川的作用加速了泥石流物源累计的速率,陡峻的地形和1200万m3的巨量冰碛物是泥石流灾害发生的根本原因;气候变化,尤其是暴雨日数的异常增加与气温的快速变化是灾害发生的诱因,当日的11.0mm/h的短历时、高强度降雨和高温天气是最终的激发因素;此外,需要注意的是,流域内选矿厂工人对泥石流灾害警惕意识不高也是造成此次灾难的重要原因。根据贡山县的实际情况,结合怒江流域泥石流分布密度较高的特点,建议贡山县在未来的矿产资源的开发和利用过程中,必须兼顾开发利用和环境保护,据此提出了针对矿产资源开发利用的泥石流防灾减灾对策。 相似文献
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由于特殊的地理环境、复杂的地质背景以及独特的气候特征,澜沧江流域以其美丽的自然景观和人居环境以及严重的山地灾害而闻名于世。作为重要的非工程减灾措施,滑坡、泥石流灾害的危险性评价和分区能提前识别灾害危险区域,进而合理的规避灾害风险。基于滑坡泥石流形成的基本条件,本研究选择灾害形成的地质、地貌、地震、降雨、人类活动等五类因素,包括坡度、地形起伏度、活动断层密度、地层岩性、地震能量、多年平均降雨量、年降雨量变差系数、土地利用类型等8项评价指标开展了澜沧江流域的滑坡泥石流危险性分区。基于大量的野外考察、多源遥感影像解译,获取了澜沧江流域715处滑坡、986处泥石流灾害点的空间分布。滑坡、泥石流灾害点的空间分布结果与灾害的危险性等级具有良好的正相关性,直接验证了本研究的危险性分区结果,为流域灾害防灾减灾和规划安全的人居环境提供了重要的决策依据。 相似文献
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Oil contaminated soil was collected from Huangpu River-Yangtze River estuary wetland, with the aim of isolating oil-degrading microorganisms and evaluating their ability to degrade diesel. Three bacterial strains were discovered and identified by sequencing their 16S rDNA genes, two were Pseudomonas and one was Alcaligcnes. The proper growth conditions of each bacterium were measured and presented for diesel biodegradation. Biodegradation assays revealed that the degradation rates of three bacterial strains were 42.5%, 14.6% and 15.9% in 7 d respectively. They all play an important role on the nalkanes within the range of C16-C25 components of diesel. The results indicated that the oil-degraders can adapt to degrade diesel. The bacterial strains can be used in wetland diesel pollution control. 相似文献
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改革开放以来,我国的广播外宣逐步从中央扩展到地方。在新形势下,如何充分发挥广播优势,加强对外宣传,为地方的对外开放和区域合作服务?本文就此作一浅析、探讨。一、顺势而为,拓宽外宣领域近年来,随着中国—东盟博览会 相似文献
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苏鹏程 《语文世界(高中版)》1998,(5)
作为一个地道的赣榆入，家乡有地多地方今我引以为荣，不过最令我们赣榆人津津乐道的，莫过于“赣榆八景”，诸如吴峰望日、夹谷闻啻、泊船锦缆等等，但我印象最深的还是一兴庄夜雨”，共庄是一个古老的渔村，在我们县东北部，它的东面两公里便是黄海，今年夏天．我随舅舅来到他的单位——兴庄小学玩耍、到了晚上，由于大气；习热，我迟迟不能入睡，直到半夜，还瞪大眼睛躺在床上。过厂一会儿，我刚有点睡意，突然外面传来“吧嗜——吧嗜——”的响声，起初，这响声稀稀疏疏，不久就像放鞭炮似地响成一片，“下雨了I’俄心自一阵惊喜，随着… 相似文献
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Oil spills may considerably damage sensitive coastal wetlands. The phytoremediation potential and restoration of a dominant coastal marsh plant, Cyperus rotundus, for diesel pollutant and its phytoremediation effectiveness were investigated in this open-air pot experiment. Cyperus rotundus was transplanted into soil contaminated with diesel at concentrations of 1 000, 5 000, 10 000, 15 000, 20 000 mg/kg. In order to better elucidate the biochemical and physiological responses to diesel pollutants, activity of the antioxidant enzymes peroxidase （POD）, catalase （CAT） and ascorbic acid oxidase （AAO） were determined in the plant tissue after 50 d treatment at the levels mentioned above. The results showed that CAT and AAO of stem and leaf exhibited peak enzyme activities on 15 000 mg/kg soil and 10 000 mg/kg soil respectively, and declined at higher concentrations. Additionally, the increment of biomass and the content of soluble protein, as well as chlorophyll content were affected by diesel. The highest restoration effectiveness appeared at the level of 5 000 mg/kg. Collectively, Cyperus rotundus is a potential plant which can be used for restoring the diesel-contaminated soil. 相似文献
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Daqing Wetland was contaminated by heavy metals for holding lots of industrial and domestic waste water. Due to their high stability and non-degradation, heavy metals are possible to gather in human body through the food chain and then threaten health. Water samples were collected from Longfeng Wetland and lake marshes in the vicinity of Daqing City. The contents of heavy metals （Cd, Pb, Cr, Cu, Zn, Ni） were determined, and the contamination degrees were evaluated simultaneously. The results indicate that heavy metals of Zn, Ni, Cd, Cr and Pd have contaminated the Longfeng Wetland severely. In addition the concentrations of Cr and Cd in some lakes around oil wells are excessively high, and have overrun the grade V based on the threshold values of surface water given by the National Environmental Protection Agency of China. Some measures have to be taken to tackle heavy metal contamination of Longfeng Wetland and lake marshes in Daqing City. 相似文献