The impact of the friction of distance on the early settlement and development of Eyre Peninsula,South Australia

The cost of overcoming distance has played and continues to play an important role in the evolution of Australia's space‐economy. This paper examines the impact of the ‘friction of distance’, as well as the quality of the resource base, on the settlement and development of Eyre Peninsula in South Australia. A series of maps portraying the spread of pastoralism and then agriculture on Eyre Peninsula reveals clearly the importance of ‘accessibility’ in influencing the pattern and timing of settlement. It was not until well into this century that all the potentially agricultural land in the interior was occupied, for this required the construction of a railway and water pipeline up the centre of the peninsula.     

我国化工地质工作的回顾与展望

50年来我国化工地质找矿及相关的研究工作都取得了显著的成绩,虽然我国化工矿产种类较齐全,但人均占有资源量偏低,保证程度与需求相比尚有不同程度的差距。化工地质工作今后应统筹规划,突出重点;发挥优势,确保化工;面向市场,拓宽领域,狠抓基础,强化竟争;严格质量,规范管理;科技创新,加强装备;突出效益,转变机制;争取政策,多元投入。在化工地质队伍推行“三新、两高、两精”的运行机制。为确保“十五”期间工作部署能顺利实施,需要国家在宏观层面上给子相应的政策支持。     

论中国东部大型盆地区及邻区地质-地球物理复合尺度解析

作为对中国东部陆缘地带大型盆地区及邻区地质－地球物理综合研究的部分结果,本文的基本认识：（1）穿过松辽盆地的1孙吴－双辽断裂可能是东倾伯低角度壳内断裂;（2）松辽盆地和渤海湾盆地可能属于“混合型裂谷盆地”;（3）东海盆地台北坳陷处在多期次张性应力场环境中,使在其西部附近产生张性正断层系;（4）欧亚大陆东部新生代区域构造运动总体处于右旋走滑拉张环境,其动力因素包括板块运动和地幔物质运动;（5）研究区莫霍面具有较为复杂的变化;（6）复合尺度研究方法是地质－地球物理综合分析的必要手段。     

融入WTO——为农业服务的化工矿产资源发展战略构想

我国直接为农业服务的磷、硫、钾矿资源总体形势不容乐观。针对各自资源特点,应采取不同的发展战略:磷——立足国内,有进有出,南出北进;硫——立足国内,适当进口,调整结构,必要储备;钾——稳定进口,国外开发,国内开发,国内找矿,四位一体,分三步走。为此建议:将磷、硫、钾纳入战略性矿产资源的范畴进行管理和规划;强化地勘队伍,加大找矿力度;增加投入,寻求新的突破;加大“走出去”的步伐;规范进出口秩序;国家在更高的层面进行宏观调控;拓宽为农业服务的新领域。     

Direct simulation of solute recycling in irrigated areas

Solute recycling from irrigation can be described as the process that occurs when the salt load that is extracted from irrigation wells and distributed on the fields is returned to the groundwater below irrigated surfaces by deep percolation. Unless the salt load leaves the system by means of drains or surface runoff, transfer to the groundwater will take place, sooner or later. This can lead to solute accumulation and thus to groundwater degradation, particularly in areas where extraction rates exceed infiltration rates (semi-arid and arid regions). Thus, considerable errors can occur in a predictive solute mass budget if the recycling process is not accounted for in the calculation. A method is proposed which allows direct simulation of solute recycling. The transient solute response at an extraction well is shown to be a superposition of solute mass flux contributions from n recycling cycles and is described as a function of the travel time distribution between a recycling point and a well. This leads to an expression for a transient ‘recycling source’ term in the advection–dispersion equation, which generates the effect of solute recycling. At long times, the ‘recycling source’ is a function of the local capture probability of the irrigation well and the solute mass flux captured by the well from the boundaries. The predicted concentration distribution at steady state reflects the maximum spatial concentration distribution in response to solute recycling and can thus be considered as the solute recycling potential or vulnerability of the entire domain for a given hydraulic setting and exploitation scheme. Simulation of the solute recycling potential is computationally undemanding and can therefore, for instance, be used for optimisation purposes. Also, the proposed method allows transient simulation of solute recycling with any standard flow and transport code.     

Pore scale modeling of immiscible and miscible fluid flows using smoothed particle hydrodynamics

A numerical model based on smoothed particle hydrodynamics (SPH) was developed and used to simulate immiscible and miscible fluid flows in porous media and to study effects of pore scale heterogeneity and anisotropy on such flows.     

山东黄泛区农村饮水安全问卷调查分析

解决农村的饮用水安全是国家“十一五”规划的重要内容之一,饮用水安全直接关系到广大人民群众的身心健康和生命安全,关系到我国农村经济的发展。结合“十一五”规划研究项目,对山东省农村饮水安全问题严重的黄泛平原区的饮水现状进行实地调研和农户问卷调查。对问卷中设计的农村饮水安全的各项内容进行统计分析,发现山东黄泛平原区存在水源中氟、砷含量严重超标,供水保证率低、农民水价格承受能力低等问题,农村饮水安全形势严峻,亟待解决。     

基于掌上电脑的智能林火标绘仪的设计与实现

本系统是利用掌上电脑的屏幕触控技术,开发智能标绘功能,使防火工作人员在发现着火点的同时依据导航信息快速地在电子地图上标绘火头、火线的位置,撰写火情报告并输出态势图,然后通过无线上网功能,实时将标绘的信息传送给防火指挥中心,为指挥中心及时做出扑火决策提供支持。     

宁夏鸳鸯湖电厂空冷气象条件分析

通过在宁夏鸳鸯湖电厂建立气温、风向、风速60 m梯度及地面观测站,与邻近的灵武市气象站展开为期一年的同步观测,获得实地观测资料。利用两地同步气象观测资料进行对比分析,揭示出电厂所在地气候特点。同时结合灵武市气象站1971~2000年观测资料,采用相关性分析方法,订正得到电厂地面历年气象要素特征值。结果表明,电厂风向和风速特征明显有别于邻近的灵武市气象站。分析结果主要用于该地火电厂空冷系统的安装与安全运行。