湖南省主要稀有稀土金属矿床特征

湖南省主要有铌、钽、铷、铯、锂、铍、锆等稀有金属及稀土金属矿床．矿床类型以岩浆晚期分异交代型、气成热液型、佛晶岩型、风化壳型和砂矿型为主．稀有稀土金属矿床在空间分布与成因上，与东山期花岗岩体密切相关，往往具有水平分带和垂向分带规律．     

青藏铁路可调式通风管路基的数值仿真分析

Finite Element Method has been used to operate the numerical analysis and comparison between the traditional ventilated embankment and the adjustable ventilated embankment adopted in Qinghai-Tibet Railway construction. The numerical results show that: 1) The adjustable ventilated embankments can prevent the thermal entry from air into ducts during summer from thawing the permafrost beneath the embankments; 2) The cooling effects of the adjustable ventilated embankments on permafrost is much better than the traditional ventilated embankments although two kinds of embankments can generate the thawing bulbs at the beginning of finishing construction; 3) The drop of the mean temperature of permafrost under the adjustable ventilated embankments keeps faster than that of the mean temperature of permafrost under the traditional ventilated embankments. It is clear that the adjustable ventilated embankments can keep the embankment more stable than the traditional ventilated embankments.     

青藏铁路通风路基边界条件研究

In permafrost regions, many methods about active cooling embankment are put forward, one of these representations is ventilated embankment, its cooling effect is the result of the air convection in the duct, and this leads to reducing the annual average ground temperature. The present work in this article is to determine the boundary conditions of the ventilated embankment and natural ground in numerical work. There are several effects which influence boundary conditions, they are: radiation, evaporation,phase change, convection and embankment material etc. Radiation and convection are the main effects in those. We mainly consider sun radiation in this article. The added-surface effect in ventilated embankment lowers its temperature, so the temperature on the wall of the ventilated embankment is different from the temperature in atmosphere. There are two methods in determining the surface temperature, experimental method and experiential method. Detailed research is discussed in the article.     

混合法计算GB体波理论地震图

高斯射线束（GB）方法是一种用于计算不均匀介质中波场的高频近似方法。本文在详细讨论了几种用高斯射线束叠加计算理论地震图的方法--频谱法、褶积法和波包法之后,提出了适用范围更广泛的混合方法（褶积-波包法）,并给出了一个便于数值计算的褶积公式。混合法在计算GB理论地震图时既用褶积法又用波包法,可以得到较高的计算速度与精度。最后,就二维情况分别用褶积法、波包法和混合法进行了一些实际计算和比较。     

宫井洋大黄鱼遗传多样性的RAPD分析

采用随机扩增多态性DNA(RAPD)技术对取自宁德官井洋闽—粤东族大黄鱼的野生种群和养殖群体进行遗传多样性分析.结果表明,野生种群的平均多态性为18.9%,平均遗传差异度为0.0960;养殖群体的分别为16.7%和0.0747;野生种群与养殖群体之间的相似系数为0.9959,遗传距离为0.0041.分析结果表明官井洋大黄鱼野生种群和养殖群体遗传多样性水平较低的主要原因在于过度捕捞、有效繁育群体数量偏少及值得探讨的人工放流等.提出官井洋大黄鱼仍具有一定的变异潜力,尽快采取有效的管理保护措施,可以保持乃至提高大黄鱼现有的遗传多样性水平.     

官井洋野生与养殖大黄鱼同工酶的研究

应用矣丙烯酰胺凝胶电泳（PAGE）法对取自福建宁德官井洋海区养殖群体和野生种群各20尾大黄鱼的9种同工酶15个基因座位于检测分析，结果表明，大黄鱼眼球中浮酸脱氢酶（LDH）酶谱表现为LDH的经典模式即有5种谱型LDH，在氙检测出的15个基因座位中，野生种群样品的编码苹果酸怪酶(sMDH)，苹果酸酶（ME）和琥珀酸脱氢酶（IDDH－1）的3个基因座位具有多态性，养殖群体中仅发现1个基因座位具有多态性（IDDH－1）所检测的野生种群比养殖群体的遗传变异水平高，但从总体上平高，但从总体上来说，官井洋大黄鱼遗传多样性相对较低，表明该种群已出现了种质退化现象，因此，进行科学的遗传管理对保护和恢复大黄鱼资源是相当必要的。     

黑龙江嘉荫地区古近纪早期古气候分析

黑龙江嘉荫地区是在我国范围内最有希望找到确切陆相白垩系一古近系界线的地区之一,定量研究界线附近古气候变迁有助于了解该界线前后的生物灭绝与复苏过程。本文以乌云组含煤段第10层所产20属29种木本双子叶被子植物化石为根据,定量研究了嘉荫地区白垩系古近系界线之后的生物复苏的环境条件。“叶相一气候多变量程序”定量分析结果显示,该区古近纪早期年均温度(MAT)约11．45℃,属暖温带气候类型;“叶缘分析”得出年均降水量(MAP)约为1424mm,林相总体上属混交中生林。     

瞬变电磁测深的微分电导成像

通过对等效导电平面方法原理的阐述,指出了利用视纵向电导参数进行瞬变电磁测深资料解释的优越性。同时,为了提高对电性层位的分辨能力,在明确电导及其导数曲线物理含义的基础上,采用B样条函数对实测数据进行处理,实现了电导参数的微分成像。实践证明,采用该方法的成像结果与其他反演结果吻合较好,其“电性同相轴”以直观、形象的面貌清晰地展示了电性界面的分布形态。      

旅游建筑水环境后效与调控模型

许多风景区内或其流域上游,都建有旅游建筑,而且在急剧增多,导致自然环境日趋恶化,其中乱建疗养院和旅馆的影响最为严重。通过实地监测并全面分析张家界金鞭溪水环境演变趋势,发现住宿设施对水环境的影响,比其他游乐设施更为明显。金鞭溪水质恶化主要表现为蓝藻,绿藻迅速繁殖,感官质量下降。主要原因是磷污染较重,总磷年均值100%超标。基于水环境因子的动态阈值调控模型,计算得出:在不超出金鞭溪水质标准:总磷≤0.02前提下,其上游接待区住宿设施生态阈值的动态系列:春季临界床位数为1?186,夏季为3?057,冬季为545,秋季为333。目前的建筑规模已超过了金鞭溪上游接待区住宿设施生态阈值。     

Jurassic Subduction of the Paleo-Pacific Ocean in NE China: Zircon U–Pb and Sr-Nd-Hf isotopic Evidence from the Huashan and Taili Monzogranites

The Qilian orogen along the NE edge of the Tibet‐Qinghai Plateau records the evolution of Proto‐Tethyan Ocean that closed through subduction along the southern margin of the North China block during the Early Paleozoic. The South Qilian belt is the southern unit of this orogen and dominated by Cambrian‐Ordovician volcano‐sedimentary rocks and Neoproteozoic Hualong complex that contains similar rock assemblages of the Central Qilian block. Our recent geological mapping and petrologic results demonstrate that volcano‐sedimentary rocks show typical rock assembles of a Cambrian‐early Ordovician arc‐trench system in Lajishan Mts. along the northern margin of the Hualong Complex. Island arc rocks including basalt, andesite, dacite, rhyolite, and breccia is in fault contact with ophiolite complex consisting of mantle peridotite, serpentinite, gabbro, dolerite, plagiogranite, and basalt. Accretionary complexes are tectonically separated from the ophiolite‐arc rocks, with various rock assemblages spatially. They consist of pillow basalt, basalt breccia, tuff, chert, and limestone blocks with a seamount origin within the scaly shale in Dingmaoshan and Donggoumeikuang areas, and basalt, chert, and sandstone blocks within muddy shale matrix and mélange at Lajishankou area. Abundant radiolarians occur in red chert, and trilobite, brachiopod, and coral fossils occur within Dingmaoshan limestone blocks. Although partial basalt or chert blocks are highly disrupted, duplex, thrust fault, rootless intrafolial fold, tight fold, and penetrative foliation are well‐developed at Donggoumeikuang area. Spatially, accretionary complexes lie structurally beneath ophiolite complex and above the turbidites of the Central Qilian block. Ophiolite and accretionary complexes are also overlapped by late Ordovician molasse deposits sourced from Cambrian arc‐trench system and the Central Qilian block. These observations demonstrate that a Cambrian‐early Ordovician trench‐arc system within the South Qilian belt formed during the early Paleozoic southward subduction of the South Qilian Ocean collided with the Central Qilian block prior to the late Ordovician.