4 research outputs found

    内蒙古农牧交错区农耕地土壤风蚀规律的风洞试验研究

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    该研究采用室内风洞试验,在不同风速、坡度及土壤含水量条件下,对两种不同质地土壤的风蚀规律进行了研究。研究结果表明,土壤风蚀量随风速的增加而增加,并存在临界风速,当风速大于此临界值时风蚀量急剧增加,但土壤的质地不同,其风蚀量增大的幅度亦不相同;同时两种土壤的风蚀量存在临界坡度,当吹蚀坡度超过此临界值时风蚀量随着坡度的变化又增加变为减少,壤土的临界坡度为20°,砂壤土10°。增加土壤含水量可以显著降低土壤的风蚀量,对于扰动土,壤土和砂壤土均存在一个5%的临界土壤含水量,当土壤含水量大于临界值时,两者的风蚀量随着含水量的增加而减少的程度明显增强,且壤土的风蚀量总体上高于砂壤土。对于未扰动土,壤土和砂壤土的风蚀量随土壤含水量的降低而增加的趋势均不明显,特别是对于壤土,当土壤含水量相同时扰动土的风蚀量明显大于未扰动土的风蚀量,说明减少表层土壤的扰动可以显著抑制土壤风蚀的强度

    Applications of New Activated Carbon Meterials in the Electric Double-layer Capacitor

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     以椰壳为原料,利用特定的物理 化学方法在一定条件下制得双电层电容器活性炭电极材料.实验表明,该活性炭经压制成型后制作的双电层电容器,具有大的比电容,文中同时研究了酸处理、二次活化以及电极冷压成型方法对电极性能的影响.A new type activated carbon whose precursor was coconut shell could be obtained using specific physics-chemistry activation, and the activated carbon was applied as the material of electrode in EDLC(electrical double-layer capacitor),which had a large specific capacitance,and could charge and discharged in some large currents. Carbon dioxide and acid were used to modify carbon,and the effects of post-treatment on surface area and pore volume were investigated. A moulding method which has influence on some properties of carbon electrode with PTFE additive was researched in the paper.作者联系地址:上海大学环境与化学工程学院,上海大学理学院化学系,上海大学理学院化学系,上海大学理学院化学系,上海大学理学院化学系,上海大学理学院化学系,上海大学理学院化学系 上海200072 ,上海200436 ,上海200436 ,上海200436 ,上海200436 ,上海200436 ,上海200436Author's Address: 1, JIANG Hua~2,FANG Jian-hui~*2,SHI Li-yi~2,YIN Ren-he~2,WEN Yi~2, LIU Ji-quan~2 1.School of Environmental and Chemical Engineering,Shanghai University,Shanghai 200072,China, 2. Department of Chemistry, College of Sciences, Shanghai University,Shanghai 200436,Chin

    DUPAL同位素异常地幔时空演化:来自古洋地幔域的证据[C]

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    本文通过收集整理了现代大洋MORB,年龄较老的印度洋MORB,典型特提斯洋构造域蛇绿岩单元内MORB型基性岩的Nd-Pb同位素数据,进一步与古亚洲洋蛇绿岩同位素数据进行对比研究表明自570Ma以来从古亚洲洋地幔域到特提斯洋地幔域均存在DUPAL同位素异常,从时间尺度上追踪了DUPAL异常的变化关系,根据DUPAL地幔随时间的演化关系提出了“地幔稀释效应”模型,在随后数百万年之中,由于地幔对流作用把DUPAL异常的强度逐渐弱化稀释而降低至现今的印度洋地幔DUPAL异常基准的水平
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