咸水湖泊沉积物中正构烷烃及其氢同位素组成与成因

青海湖是我国最大的内陆咸水湖泊,对这种湖泊沉积物中正构烷烃及其氢同位素进行了分析,研究了沉积物中正构烷烃及其同位素组成,并且与青海湖水生植物及其周围陆生植物的研究结果进行了对比,研究了它们的成因.结果显示了青海湖表层和柱状沉积物中正构烷烃分布都是类似的,其特征反映了它们起源于湖泊周围陆生草本植物.青海湖表层沉积物中正构...     

UPVC井管在云南抗旱供水井中的应用

在水井工程中,国外现在应用较多的是UPVC全塑料井管,而在我国却不然。分析了UPVC全塑料井管在水井应用中的优缺点,并通过其在云贵高原的应用实例,介绍了UPVC全塑井管在下井管、止水、洗井工艺中的关键技术。实际应用表明,UPVC井管可以保证成井质量,提高施工技术,UPVC全塑井管在农村及干旱地区的应用前景巨大,有很好的推广价值。     

Internal Structure of Cambrian Fossil Embryo Markuelia Revealed in the Light of Synchrotron Radiation X-ray Tomographic Microscopy

In the light of Synchrotron Radiation X-ray Tomographic Microscopy (SRXTM), the internal structure of Markuelia hunanensis is revealed. In one example, vitrification and peeling show the annuli hidden under the chorion. Sectioning and 3-D reconstruction display an intact digestive tract from the inverted introvert to the terminal anus. The inverted introvert forms a rugby cavum. The following digestive tract is rope-like coiling, parallel to the body axis, about 650 μm in length, and uniform in diameter (~80 μm). An exquisitely preserved pipe-like structure is hidden in the middle of the rope-like structure, diameter 20–40 μm, with a length of ~120 μm. We interpret this pipe-like structure as the possible epidermis of the gut and its surroundings as the possible residue of musculature, similar to that in Priapulans. The two symmetrical rod-shape structures connecting the body wall and digestive tract are interpreted as the possible retractor muscles. After comparing the well preserved Left-form and Right-form Body of Markuelia, we suggest that they may represent a dimorphism. Counted directly, one sample of Markuelia hunanensis possesses 62 annulations and the other 68.     

柴西地区上干柴沟组上段咸水湖相烃源岩生烃条件研究

柴西地区上干柴沟组上段(N12)烃源岩的沉积水体环境为咸水湖相。其烃源岩的有机质总体丰度不高;有机质类型主要有腐殖腐泥型和腐殖型,具体分布受烃源岩所处位置及沉积环境控制;有机质成熟度多为未成熟-低成熟;有机质的烃转化率较高,反映其大部分有机质已经进入生烃门限,少量已经进入生烃高峰期。其烃源岩具有咸化湖泊相未熟-低熟有机质生烃的特点,而其生烃机理很可能是藻类生物类脂物和细菌的早期成烃。柴西地区上干柴沟组上段(N12)烃源岩作为该区未熟-低熟石油主要源岩之一,具有非常大的勘探潜力。     

基于模糊数学的地质灾害危险性评价

陕西省引汉济渭工程跨越秦岭构造剥蚀山地和断陷盆地,地质环境条件差,发育地质灾害点72处。选取地质环境条件、地质灾害发育现状和地质灾害预测为评价指标,分别赋予隶属度值;将工程剖分为284个评价单元,采用模糊数学综合评判法计算每个单元的隶属度值,确定危险性小的单元255个,危险性中等的单元29个;说明工程主要位于危险性小的区段。     

Evaluation of EDI derived from the exponential evapotranspiration model for monitoring China’s surface drought

Drought has become the most severe natural disaster in many provinces of China. In this paper, evaporative drought index (EDI) has been used to monitor China’s surface dryness conditions based on the exponential evapotranspiration (ET) model and Hargreaves equation from JAXA-MODIS Insolation products, GEWEX, NCEP-2 and MODIS NDVI data. The exponential ET model based on the surface net radiation, vegetation index, mean air temperature and diurnal air temperature range (DTaR) has been developed to estimate surface ET of China and has been independently validated using ground-measured data collected from two sites (Arou and Miyun) in China, indicating that the bias varies from −5.96 to 5.02 W/m². The good agreement between daily estimated and ground-measured ET using ground observation data collected from all 22 sites further supports the validity of the exponential ET model for regional ET estimation. Moreover, EDI is closely correlated to the average soil moisture at 0–10 cm soil depth of the Yongning site with coefficient of determination of R ² = 0.52. The spatio-temporal patterns of monthly ET and EDI from April to September of 2004 over China are explored and the result indicates EDI is accordant with the precipitation by comparing the 15-day smoothed EDI with precipitation over six representative sites. The EDI based on the exponential ET model by integrating energy fluxes in response to soil moisture stress has demonstrated its validity for monitoring China’s surface drought events.     

青海南部曲麻莱县加容检德工卡侵入岩序列特征及其构造环境

加容检德工卡侵入岩序列由石英闪长岩-英云闪长岩-花岗闪长岩-正长花岗岩组成。岩石化学成分表现为从中基性到酸性的演化及岩浆向富硅、富碱方向演化。稀土元素特征表现为轻稀土元素富集;微量元素特征表现为富集大离子亲石元素Rb、K、Ba、Th,而Sr、Nb、Ta略显亏损,Ti、P较强亏损。构造环境为同碰撞花岗岩,时代为早白垩世。     

1013号超强台风“鲇鱼”北折路径分析

应用日本JMA数值产品的格点资料和实况场分析资料,重点对1013号超强台风“鲇鱼”西行进入南海后发生近90°直角转向偏北移动,直至登陆福建的这一阶段路径进行分析.“鲇鱼”先是受位于华南的西环大陆副高引导,向西南西移动,之后转受加强北上的赤道高压引导,折向北到北偏东方向移动,最后受东环副高引导北偏西行至登陆福建.在这3个...     

新型蛋白源替代鱼粉对星斑川鲽幼鱼蛋白酶活力和表观消化率的影响

以星斑川鲽(P latichth ys Stellatus;初始体质量为75.6士0.18 9)为研究对象,以新型蛋白源(大豆浓缩蛋白、脱酚棉籽蛋白、喷雾干燥血球蛋白粉等)为原料,通过调节饲料氨基酸水平,配制出5种等氮等能的饲料D0、D17、D35、D52和D69,其中D0(添加58％脱脂鱼粉)为对照组,其余各组分别替...     

京津风沙源区生态环境时空变化的遥感监测分析

本文利用由遥感影像解译获得的土地利用数据和MODIS NDVI产品,采用空间转移矩阵、最大值合成法、均值法和一元线性回归模拟等方法,分析了2000年以来京津风沙源区生态环境变化的时空特征.结果表明:(1)2000-2005年京津风沙源区耕地开垦、林草地减少的趋势有所减缓,但区域气候变化趋于干旱,水域面积明显减少,草地退...