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111.
江兴权 《广东海洋大学学报》1989,(Z1)
本文仿照straub离体蛙心灌流法,用浓度为10~(-6)M至10~(-3)M的拟腎上腺素药物0.05-0.25m1注入1.5m1灌流液中,观察腎上腺素、去甲腎上腺素、异丙肾上腺素、间羟胺和甲氧胺对黄鳝、乌鳢、尼罗罗非鱼、胡子鲶和埃及胡子鲶离体心脏的影响作比较,并进行心肌受体分析。实验结果表明,拟腎上腺素药物对不同种类鱼离体心脏活动的影响不同,不同种类的鱼心肌腎上腺素受体也不同。这与鱼类种属不同有关。而拟腎上腺素药物对胡子鲶和埃及胡子鲶离体心脏的影响相同:異丙腎上腺素的兴奋作用为β-受体阻断剂所抑制;甲氧胺的抑制作用为α-受体阻断剂所阻断。表明其心肌存在着β-受体和α-受体,但以β-受体的作用较明显。提示这两种同属異种鱼的心脏调节机制相同。 相似文献
112.
通过测定喂食水华微囊藻的尼罗罗非鱼胃PH值、不同颜色粪便的叶綠素/脱镁叶綠素比例,发现尼罗罗非鱼具有一个与摄食相关的胃酸分泌周期。摄食旺期胃平均PH值为1.47,最低值为0.8。停食后PH值升高,最大值为6.0。用不同浓度的盐酸处理水华微囊藻和对不同颜色粪便的营养分析结果表明,高浓度的胃酸(PH<2)溶解了水华微囊藻细胞壁,为肠消化酶对细胞内含物进行消化创造了先决条件。 相似文献
113.
高煤级煤储层煤层气产能“瓶颈”问题研究 总被引:12,自引:0,他引:12
基于山西沁水盆地高煤级煤储层宏观裂隙、显微裂隙的连续观测,孔隙的系统测量,结合应力渗透率、气-水相对渗透率、吸附膨胀等实验成果,分析了高煤级煤储层三级渗流特征,探讨了有效应力和煤基质收缩对高煤级煤储层渗透率的耦合作用,系统揭示了在地面排水降压开发煤层气的过程中,高煤级煤储层初期产气量高,数月后急剧衰减之“瓶颈”现象,找出了造成高煤级煤储层产气缺陷的根本原因。鉴于高煤级煤储层物性的特殊性,指出了高煤级煤储层煤层气开发的技术和措施。 相似文献
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115.
Giant Mineral Deposits and Their Geodynamic Setting in the Lanping Basin, Yunnan, China 总被引:6,自引:0,他引:6
XUE Chunji LIU Shuwen CHEN Yuchuan ZENG Rong ZHAO Shihua College of Earth Sciences Resources Chang''an University Xi''an Shaanxi Chinese Academy of Geological Sciences Beijing 《《地质学报》英文版》2004,78(2):368-374
There are giant mineral deposits, including the Jinding Zn-Pb and Baiyangping Ag-Co-Cu, and otherimportant mineral deposits (e.g., Baiyangchang Ag-Cu, Jinman Cu deposits, etc.) in the Lanping Mesozoic-Cenozoic Basin, Yunnan Province, China. The tabular ore-bodies and some veins hosted in terrestrial clastic rocks of the Mesozoic-Cenozoic age and no outcropping of igneous rocks in the giant deposits lead to the proposal of syngenetic origin, but the giant mineral deposits are not stratabound (e.g. MVT, sandstone- and Sedex-type). They formed in a continental red basin with intense crust movement. The mineralization is controlled by structures and lithology and occurs in different strata, and no sedimentary nature and no exhalative sediments are identified in the deposits. The deposits show some relations with organic matter (now asphalt and petroleum) and evaporates (gypsum). The middle-low-temperature (mainly 110℃ to 280℃) mineralization took place at a depth of about 0.9 km to 3.1 km during the early 相似文献
116.
SUN Aiqun NIU Shuyin SHAO Ji''an HOU Quanlin ZHANG Jianzhen Shijiazhuang College of Economics Shijiazhuang Hebei School of Earth Space Sciences Peking University Beijing Institute of Geology Geophysics Chinese Academy of Sciences Beijing 《《地质学报》英文版》2004,78(1):283-290
The basin-and-range area in eastern North China is known for frequent occurrence of earthquakes, their great magnitudes and heavy losses thereby incurred. Seismic studies in the past usually emphasized the intersections, inflexions and branches of the faults. However, the intensities of many great earthquakes in this area do not show linear distribution, and the epicenters are horizontally dispersed at certain depths instead of along the strike of faults. Based on the sub-mantle plume studies made by authors in the past decade, it is thought that there exists an uplifted sub-mantle plume under the fault depression area in North China. The uplifting and intrusion of mantle materials caused the upper crust to be faulted, while low-velocity and high-velocity layers are alternatively distributed in the middle crust under the influence of the mantle and the lower crust. The middle and lower crust materials were detached from the top of the sub-mantle plume to the surroundings while the sub-mantle plume materi 相似文献
117.
A Simple Monte Carlo Method for Locating the Three-dimensional Critical Slip Surface of a Slope 总被引:2,自引:0,他引:2
XIE Mowen Institute of Environmental Systems Kyushu University Hakozaki -- Higashi Ku Fukuok Japan College of Resource Engineering the University of Science Technology Beijing Xueyuan Ro Haidian District Beijing China 《《地质学报》英文版》2004,78(6):1258-1266
Based on the assumption of the plain-strain problem, various optimization or random search methods have been developed for locating the critical slip surfaces in slope-stability analysis, but none of such methods is applicable to the 3D case. In this paper, a simple Monte Carlo random simulation method is proposed to identify the 3D critical slip surface. Assuming the initial slip to be the lower part of a slip ellipsoid, the 3D critical slip surface is located by means of a minimized 3D safety factor. A column-based 3D slope stability analysis model is used to calculate this factor. In this study, some practical cases of known minimum safety factors and critical slip surfaces in 2D analysis are extended to 3D slope problems to locate the critical slip surfaces. Compared with the 2D result, the resulting 3D critical slip surface has no apparent difference in terms of only cross section, but the associated 3D safety factor is definitely higher. 相似文献
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120.
中国中部高铝质超高压变质岩 总被引:6,自引:3,他引:3
我国中部在超高压条件下形成的高铝质变质岩石, 以蓝晶黄玉石英岩为特征, 具有以蓝晶石、富水黄玉、富镁硬绿泥石、柯石英、硬水铝石等为代表的高压-超高压变质矿物, 矿物组合主要为蓝晶石+ 黄玉+ 石英 (柯石英)、蓝晶石+ 蓝刚玉±富镁硬绿泥石等。化学成分富铝而贫镁, 其原岩为陆缘高铝质泥质沉积岩。实验岩石学的研究表明, 蓝晶石+ 黄玉在1000℃~1200℃,3.1~3.77GPa 条件下仍可稳定存在,而石英已部分转变为柯石英。蓝晶石+ 黄玉与柯石英一起稳定于超高压条件下。这表明以高铝质岩石为代表的地壳物质已进入到地幔深度, 达到这样的深度只能由会聚板块的俯冲作用而引起。因此,高铝质岩石的存在可以作为A型俯冲作用的指示剂。超高压变质的高铝质岩石将成为陆-陆碰撞事件的重要研究内容。 相似文献