五级分支井井眼连接总成设计及有限元分析

在不稳定地层中,分支井眼连接处易发生变形破坏,为此,设计了一个分支井眼连接总成,包括2个预制的部件,模板和连接器。它们通过一个梯形导轨啮合在一起后形成一个连续的整体机械结构,配合的间隙和公差满足连接器液力密封的要求。利用有限元数值模拟对该连接总成进行了3种地层压力下的位移和内部应力分析,结果表明其变形量非常小,内部所能达到的最大应力小于N80钢的屈服强度,表明该连接总成具有较强的抗地层挤压的能力。     

煤层气井自调偏式井口密封装置研制与试验

针对煤层气井现有井口密封装置密封效果不好,造成井口有水、气体泄漏的问题,研制了一种适用于煤层气井的自调偏式井口光杆密封装置。该密封装置从上而下依次由盘根密封盒、自调偏机构、下接头3部分组成。自调偏部分由万向节结构总成和高压挠性胶管巧妙结合,使密封盒与光杆能够始终保持随动对中。现场应用表明,该井口密封装置密封性能可靠,结构简单,具有推广应用前景。      

钢筋连接新技术及其在岩土工程施工中的应用

简介了钢筋的连接技术及钢筋机构连接技术的通用规定。分析了几种钢筋连接新技术－带肋钢筋套筒挤压连接技术,锥形螺纹连接技术,钢筋等强度直螺纹连接技术,电渣压力焊接技术的应用范围、工程材料与设备、工艺流程及其在岩土工程施工中的应用前景。     

反循环钻进用水龙头结构的改进

现有反循环钻进用水龙头结构采用填料密封 ,其压紧程度不易调整 ,密封性能差。新型水龙头采用浮封环O型橡胶圈和密封环支座等密封 ,并改进了结构 ,密封可靠 ,操作简便 ,寿命长 ,成本低 ,便于故障诊断。     

衬垫密封技术是一种解决原位修复内衬密封缺陷的方法

对于原位修复管道（CIPP）内衬和水分迁移有很多的误解。尽管关于CIPP内衬与主管道结合成为复合管道的观点已经不足信了,但仍然有许多人不知道由于热固性树脂的物理性能,CIPP内衬层在聚合作用中的收缩会导致内衬层和主管道之间产生环状间隙。这个环状间隙可以让地下水进入到内衬层并流入收集系统,不仅引起污水处理总量显著增大,也增加了公厕下水道溢流（SSOs）及收集系统密封失效从而污柒地下水的风险。由于意识到这个问题,CIPP修复市场已经开始研究,并引出了采用圆柱状压力垫圈端部密封设计来解决这一问题,它可以填充CIPP施工中的无缝模塑亲水垫圈密封人井连接处和分支连接处时形成的环形空隙。整圈CIPP内衬层对低压管道设施密封问题是一个结构性解决方法。然而,正如上面所讲,单独采用CIPP内衬可能无法提供防水修复。那么,依赖CIPP内衬来实现防水密封的终端用户,将会有花费资金和资源却达不到他们目的的危险。     

天然气水合物保真取心装置内部密封技术分析

摘要：在海底天然气水合物地层钻探中,利用压力岩心取样器(PCS)获取保压岩心对于后续相关的处理和分析非常重要。首先回顾了国内保压保温取心器相关研究现状,然后从PCS取样腔内部球阀和O型圈等密封结构的特点分析了其内部上、下两部分的密封技术。在综合分析国内两种取样器密封结构特点的基础上,结合岩心现场处理与分析的特点,对PCS与上述两种取样器的密封技术进行了探讨,为取样器的密封设计、岩心现场压力和温度的保持以及保压岩心的保真转移提出了几点建议。     

砂石泵轴端密封的研究与设计

介绍了１５０ＳＢＤ－１２型离心式砂石泵轴端密封的结构原理和相应的技术措施,双浮动密封装置成功地取代了传统的填料密封,并取得了良好的使用效果。     

基坑垮塌的离散元模拟及冗余度分析

目前基于构件设计的基坑设计理论使得很多支护体系缺乏必要的冗余度,并导致了众多基坑事故。将离散元方法引入到基坑垮塌模拟和冗余度研究中,提出了基于局部破坏的冗余度分析模拟方法。进而以探究支撑端部连接对支护结构冗余度的影响为例,对两种连接情况的基坑的破坏过程进行了模拟,对其中的连续破坏现象进行了分析,并将模拟结果与实际工程进行了对比。结果表明,支护体系冗余度的提高可以有效地抵抗连续破坏的发生,防止基坑在局部损伤情况下,由一种形式的破坏引发其他形式的破坏,由局部破坏导致整体崩溃。另外,模拟结果也验证了离散元法在基坑破坏模拟中的适用性与可行性,为类似地下工程的破坏模拟和基坑冗余度的深入研究提供了参考。     

地下连续墙槽段连接技术

他目前国内外地下连续墙的槽段之间连接技术与方法，介绍了接头管，接头箱，隔板式及套打一钻等槽段纵向接头的结构形式。     

大直径反循环潜孔锤的密封方法与试验研究

可靠的密封结构是大直径反循环潜孔锤能够实现反循环钻进工艺的关键,同时也是大直径反循环潜孔锤设计的难点。现有的大直径反循环潜孔锤都是基于孔底钻具本体进行密封结构设计的。提出了一种孔底与孔口联合密封的方法,以该密封方法为设计原则研制了扩孔用φ710/311 mm集束式反循环潜孔锤与孔口密封装置,并配套φ127/70 mm双壁钻具进行了现场试验,取得了较好的连续反循环排渣效果,平均机械钻速为2.1 m/h,与常规牙轮钻头扩孔方法相比提高了2.6倍。试验结果表明孔底与孔口联合密封方法是可行的,值得进一步推广应用。     

CSAMT 法在辽西康杖子区深部探矿中的应用

可控源音频大地电磁法(CSAMT)具有探测深度大、横向分辨率高、抗干扰能力强的特点,在深部找矿勘探中有着重要的指导意义。肖家营子铜钼矿床是辽西地区一个大型矽卡岩型金属矿床,大部分矿体是隐伏矿体,矿区外围的康杖子区与本区有相似的成矿地质环境,成矿地质条件优越.矿体与围岩电性差异明显,通过应用CSAMT,矿体具有低电阻特点,根据成果推断解释,对深部有利成矿部位进行了钻探验证,取得了理想的探矿效果,在矿区外围取得第二深度空间找矿重大突破。     

Geography in general education in Nigeria

This paper traces the development of geographic education in Nigeria and examines the views of geographers, other academics, students and the public at large about the importance of geography. Geography's value is immense despite the non-professional nature of the discipline. Nevertheless, there is a need to define geography's status and ensure career prospects for students. The Nigerian Geographical Association (from classroom teaachers to top geographers) must promote geography, improve its status in schools and universities, and continuously restructure its content and methods to address pertinent social needs.     

Trends in landslide occurrence in Nepal

Nepal is a mountainous, less developed kingdom that straddles the boundary between the Indian and Himalayan tectonic plates. In Nepal, landslides represent a major constraint on development, causing high levels of economic loss and substantial numbers of fatalities each year. There is a general consensus that the impacts of landslides in countries such as Nepal are increasing with time, but until now there has been little or no quantitative data to support this view, or to explain the causes of the increases. In this paper, a database of landslide fatalities in Nepal has been compiled and analysed for the period 1978–2005. The database suggests that there is a high level of variability in the occurrence of landslides from year to year, but that the overall trend is upward. Analyses of the trends in the data suggest that there is a cyclicity in the occurrence of landslide fatalities that strongly mirrors the cyclicity observed in the SW (summer) monsoon in South Asia. Perhaps surprisingly the relationship is inverse, but this is explained through an inverse relationship between monsoon strength and the amount of precipitation in the Hill District areas of Nepal. It is also clear that in recent years the number of fatalities has increased dramatically over and above the effects of the monsoon cycle. Three explanations are explored for this: land-use change, the effects of the ongoing civil war in Nepal, and road building. It is concluded that a major component of the generally upward trend in landslide impact probably results from the rural road-building programme, and its attendant changes to physical and natural systems.     

2010年的美国铀矿业

2010年,美国铀矿总共施工7 209个钻孔,总进尺1 493 520 m;生产铀1 628.55 t;铀矿业总支出费用为2.773亿美元,其中铀矿地勘费支出为3 450万美元,占铀矿业总费用的12.44%。铀矿地勘钻探费用为4 460万美元,占铀矿业总费用的16.08%。     

地下水环境中的硫代砷研究进展

硫代砷是富硫化物地下水中砷的重要形态,对环境和人类健康有潜在威胁。目前硫代砷研究程度尚低,本次主要针对国内外地下水（地热水）中硫代砷的存在形态,水文—生物—环境地球化学过程,样品保存,定量检测方法等方面进行研究。结论如下:pH, 氧化还原电位,硫化物含量和微生物作用等是影响地下水中硫代砷稳定存在和形态分布的重要因素。含铁矿物能与水中的硫代砷形成配位键对其进行吸附,吸附性普遍弱于（亚）砷酸盐,因此,地下水中硫代砷可能表现出更强的迁移性。用于硫代砷检测的自然水样在采集中可采取过滤,速冻,厌氧和低温短期保存的操作流程,以减缓该形态的转化甚至消失。色谱联用ICP-MS系统可用于自然水样中硫代砷的分离定量检测,紫外—可见分光光度法和X射线吸收光谱法在不同场景下也可对硫代砷进行定量和表征分析。地热水和浅层地下水中均可能存在硫代砷,由于水样中硫代砷的不稳定性,室内检测和分析难以准确反映现场过程,因此,野外样品保存技术和现场检测方法的更新可能在未来有更大研究空间,值得进一步探索。     

花岗岩地区地下水水文地质特征分析

通过对泰安市岱岳区花岗岩地区地下水的形成条件、地下水类型、分布状况、水文地质特征以及地下水补给、径流、排泄条件的分析,指出了花岗岩地区供水方向。     

Recent advances in aquaculture in Japan

Conclusions During the last ten years, aquaculture, especially mariculture has undergone remarkable expansion to counter-balance the gap between the supply and demand of fishery products in Japan. Its expansion has also been supported by the traditional preference of the Japanese people for seafood. Mariculture is now being forced to change its structure due to adverse economic circumstances such as the rise in the cost of energy, feeds and other materials for culture, low market prices, deterioration of environmental conditions, and many other factors. Before these constraints can be resolved, advanced scientific knowledge and technologies must be integrated to develop new types of aquaculture. Expansion of maricultural activities to more open-sea and off shore areas would be one route to follow. Technologies for the development of formulated diets not only for young but also for adults and larvae, establishment of feeding standards, prevention of epizootic diseases must support the establishment of modern aquaculture.The culture-based fisheries, or marine ranching, is becoming a subject for further development in Japan. Much research work has been conducted with a great degree of governmental support. Establishment of a net work of seedstock production farms has made it possible to carry out releasing experiments on a large scale. A newly integrated restoration system could be developed on the basis of these experiments, even though the profits resulting from the artificial restoration of stocks is not thouroughly verified at present. The commencement of a national scheme for culture-based fisheries would be a manifestation of the enthusiasm of the Japanese fish industry.     

Some Measurements of Radon in Soils and in Stream-Water in County Durham

Radon is a radioactive gas emanating naturally from uranium rich granites and shales. It may be emitted from the ground surface into the atmosphere as a gas, or it may be dissolved into stream water and transported over distance. The levels of radon gas in soils at ground surface depend on a number of factors relating to the source of the gas and to its transmission. Igneous rocks contain the highest mean concentrations of radium and uranium. The depth of cover is relevant also. Surveys over the years by the National Radiological Protection Board (NRPB) and others have indicated that the highest concentrations in the United Kingdom occur in Cornwall, Devon and northeast Scotland. However, recent reports have indicated that high concentrations of the gas may be detected in small pockets in counties outside of those considered at high risk. This survey relates to a series of measurements taken in and around Darlington, County Durham. The results showed the presence of small areas with strong concentrations of radon in soil gas, but only minor levels of dissolved gas in stream waters.     

内蒙古苏尼特地下水氟污染形成机理研究

为了研究内蒙古苏尼特地区地下水氟污染机理,本文运用水文地球化学分类方法,从水文地质、水化学特征两方面研究其地下水的水质特征、氟的起源、分布规律及污染形成机理。研究结果发现:高氟地下水的主要水质类型为HCO3—Na型,pH值在7.08～9.38之间,氟浓度与井深有关,即井越浅,氟浓度越高;地下水中氟浓度最高达14.78mg/L,5～9月地下水氟浓度相对增长率在7.8～23.1之间;F-浓度与Li+、Br-相关系数达0.89和0.82,受断层影响的深层地下水中F-浓度几乎与Li+、Br-没有相关关系,这暗示着氟来源于浅部,并受到强烈的蒸发作用影响而使水中的氟浓缩;地质调查发现该地区还有数个萤石矿存在,显微镜分析结果证实表层土壤中普遍存在CaF2,地下水中的氟来自CaF2。高氟地下水存在于潜水层,深部含水层的地下水可供开采。从断层带涌出的水对潜水层有稀释作用。