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本文研究了0.2、2、20μg/g金雀异黄素腹腔注射金鱼(Carassius auratus) 7d后,金鱼肝胰脏和肠蛋白酶、淀粉酶和碱性磷酸酶活性的变化.结果表明:随金雀异黄素浓度的升高,金鱼肝胰脏和肠蛋白酶、淀粉酶及肠碱性磷酸酶活性都有所降低.0.2μg/g金雀异黄素处理组,金鱼蛋白酶和淀粉酶活力降低并不显著,而肠碱性磷酸酶活力显著下降(P＜0.05);2μg/g金雀异黄素处理组,金鱼蛋白酶和淀粉酶活力显著下降,碱性磷酸酶活力表现极显著下降(P＜0.01),仅为对照组的44％;20μg/g金雀异黄素处理组,金鱼蛋白酶和淀粉酶活力极显著下降,其中肠蛋白酶活性降了90％以上.本文证实了较高浓度的金雀异黄素能显著降低金鱼主要消化酶的活性,进而影响金鱼正常生长,但较低浓度的金雀异黄素对金鱼消化酶无显著影响.研究结果为大豆蛋白在水产养殖中的适量应用提供了参考数据. 相似文献
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通过研究平顶山矿区17对生产矿井的瓦斯地质特征,分析各矿井瓦斯含量、瓦斯压力和涌出量实测数据,总结了平顶山矿区瓦斯赋存分布规律。运用瓦斯赋存构造逐级控制理论厘清了区域构造演化、矿区和矿井构造对平顶山矿区瓦斯赋存分布的控制,提出了平顶山矿区瓦斯赋存的构造逐级控制特征:区域板块构造运动及演化奠定了平顶山矿区高瓦斯的基调;矿区构造李口向斜确定了矿区瓦斯东高西低、呈轴对称分布的总体规律;矿井构造主导矿井各煤层瓦斯赋存和矿井区域瓦斯赋存的差异性。研究成果为准确预测瓦斯赋存分布和预防煤与瓦斯突出提供了依据。 相似文献
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以IKONOS 1m分辨率遥感影像为例,对矿业开发活动中按露天开采面、开采硐口、固体废弃物、尾矿库、中转场地、矿山建筑等进行分类研究,总结以上六类地物在高分辨率遥感影像上的解译标志。 相似文献
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尽管美国的页岩能源革命令人振奋,但欲将其在中国复制,其给
环境带来的风险不容小觑.
业内人士和环保专家指出,页岩气开采中耗水量是常规天然气的10倍左右,且面临许多环境风险,而我国页岩气田多数分布在缺水地区,钻探一口井的环保支出需数百万元.更令人忧心的是,目前我国页岩气开发环保监管法规方面基本是一片空白,页岩气开发环境风险倍增.为此,专家建议,国家有关部门和地方政府应尽快制定与此页岩气开采相关的环境法律法规,完善全程环境监管体制. 相似文献
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大尺度背景下西北太平洋热带气旋的统计分析 总被引：2，自引：0，他引：2
利用大尺度再分析资料和静止卫星云图资料,对1995-2004年西北太平洋热带气旋（TC）形成的大尺度环流背景进行了分类研究。在这10a期间,有27．5％的西北太平洋TC形成于赤道辐合带,45．6％形成于季风槽,10．1％形成于东风波,10．4％形成于热带对流层上部槽,6．3％形成于斜压性扰动条件下。统计分析表明,斜压性扰动背景下形成的TC在生命史、强度方面均明显弱于其他情况,平均生命史为108．60h,平均强度为39．250kn,其余4种情况平均生命史约为200h,平均强度为70～80kn。季风槽情况下形成的TC每3个就有一个会登陆我国,其次是东风波情况下的TC,斜压性扰动背景下形成的TC必须在南海附近生成才有可能登陆我国。 相似文献
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The Shimen realgar deposit is characterized by the pipi-shaped orebody and the development of silica sinter and hydrothermal explosive breccia which are typical of hot spring activity.Very similar trace-element associations are noticed between the silica cap and the breccia and modern hot spring waters in the area.The chemistr of ore-forming solutions is also well comparable with that of modern hot spring.,The spring system that gave rise to the mineralization was charged by ground waters heated through thermal conducting systems in the deep crust and,to a lesser extent,by geothermal gradient.ΔD,δ^18O,δ^13CCH4andδ^13CH4andδ^13CCO2values and ^40Ar/^36Ar and 3^He/^4He ratios indicate that the spring system is of crustal derivation.The ore-forming metals were supplied by surrounding strata,particularly those underlying the ore deposits.The mechanim of ore deposition is thought to be hydrothermal explosion and accompanying boiling and abrupt changes in pH and Eh.Located in northwest Hunan,the Shimen realgar deposit is the leading arsenic producer in the country,However,regardless of its long mining history,the genesis of this deposit has long been a puzzle.It was considered to be postmagmatic epithermal in the leading arsenic producer in the puzzle.It Was considered to be postmagmatic epithermal in origin,but this is trongly challenged by filling(metasomatism)in karst environment proposed later by Zhou Zhiquan(1986)also encounters a number of difficulties.For example,why can the pipi-shaped orebody vertically extend up to several hundreds meters without any compatible development in the lateral dimension? A hot spring genesis is suggested in the present paper based on geological observations and laboratory studies conducted by the authors in recent years. 相似文献