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地理实验是一种直观、形象的教学方法，它通过实验手段，高效率地展示人们认识和发现某一地理知识、原理的过程，揭示地理事物的分布、发展、变化规律。地理实验教学从实验设计、实验操作、实验观察记录、整理资料、分析研究得出结论等过程中培养学生多方面的能力。在实验中，学生需要敏锐细致地观察和发现一些重要现象，从中培养观察能力；对实验现象的原因推究和结果推测，需要做分析、 相似文献
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根据地理信息系统课程的特点,针对资源环境与城乡规划管理专业,提出基于Arcview软件的地理信息系统课程实验设计,包括实验要求、实验内容与具体课时安排等。学生通过学习实践,可以加深理解地理信息系统的理论、技术和方法,为本专业相关领域应用问题的分析和解决打下基础。 相似文献
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为了研究泡沫钻进中泡沫流休压力损失的变化规律，建立室内模拟试验台，通过大量实验，得出结论。 相似文献
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A new kinetic spectrophotometric method has been developed for the determination of trace Ni (II) in natural water.The method is based on the catalytic effect of Ni (II) on the oxidation of weak acid brilliant blue dye (RAWL) by KIO4 in acid medium.The concentration of nickel (II) can be determined spectrophotometrically by measuring the decrease of absorbance of RAWL at λ= 626 nm using the fix-time method.The influencing factors are investigated by the orthogonal experimental design.The obtained optimum analytical conditions are:pH=2.00,c RAWL=5.00×10-5 mol L-1,cKIO 4= 2.00×10-5 mol L-1,the reaction time t=10 min and the temperature T=25℃..Under the optimum conditions,the developed method allows the measurement of Ni (II) in a range of 0-40.0 ng mL-1.The standard deviation of eleven independent measurements of blank reaction is S=3.08×10-3 and the limit of detection is 2.20 ng mL-1.The relative standard deviations (RSDs) in six replicate determinations of 5 ng mL-1 and 8 ng mL-1 Ni (II) are 2.87% and 1.11%,respectively.Moreover,the experiments show few cations and anions can interfere with the measurement of Ni (II).The recovery efficiencies of this method are in a range of 97.0%-102.5% in freshwater samples.But there is a decreasing effect,which is about 0.2 times the added Ni (II) in seawater medium.After reasonable calibration this processing method is used for the determination of Ni (II) in seawater samples successfully.The results show this developed method has high accuracy and precision,high sensitivity,large range of linearity and high speed.The method can,therefore,be employed at room temperature. 相似文献