过去5000年西太平洋副热带高压活动的泥炭纤维素碳同位素记录

文章以金川和红原两组泥炭纤维素Δδ¹³C时间序列值的反向变化来指示西太平洋副热带高压活动变化.结果表明,在过去5000年中,西太平洋副热带高压的活动可分为4个阶段,即西太平洋副热带高压位置在2800～2200B.C.期间持续偏北,2200～600B.C.期间持续偏南,600B.C.～1200A.D.期间在北进与南移之间频繁波动,以及1200～1900A.D.期间再次持续偏北,它们导致降雨量在中国大陆上不同的分布.从约1900A.D.起西太平洋副热带高压的活动似乎又开始一个新的偏南阶段,值得进一步加强研究.     

油田开发中的相态特征及流体组份研究--以大张坨凝析气藏为例

大张坨凝析气藏是在我国发现的高含量凝析气藏之—．开发中据相态特征及流体组份研究结果，适时调整开发方式．1994年开始试采，1995年初实施循环注气开发．该气藏的开发经历了衰竭试采循环注气2个开采过程，开发过程中定期取地层流体样品进行相态特征和流体组份研究，并注重其成果的应用，凝折油采出率29．0％，取得了较好的开发效果．证实了相态研究在凝析气藏循环注气开发全过程应用的重要性．     

江苏省若干代表站年降水量的多年变化和系列代表性分析

利用长系列雨量站资料，采用数理统计法分析了江苏省年降水量的多年变化，对1956—2000年、1956—1979年、1971—2000年、1980—2000年等短系列年降水量的系列代表性做出了分析评价，为合理选用水文系列提供了依据，对江苏省水资源调查评价和水资源综合规划具有重要的参考价值，可在生产中应用。     

Monsoonal precipitation variation in the East Asia since A.D. 1840 ——Tree-ring evidences from China and Korea

The main characteristic of the East Asian climate is the monsoon system. Plenty of studies have demonstrated that the Asian monsoon system plays a crucial role in the global climate sys- tem [1-4]. The Asian summer monsoon can be divided into two parts, t…     

大同市区二十年地下水动态研究

本文首先分析了大同市地下水开采与地下水降深之间的对应关系，同时分析了影响地下水动态的其它因素，然后将地下水开采和大气降水量这两个影响地下水动态的主要因素与地下水动态进行复相关计算，求出相关方程，并进行不同开采量的地下水降深预测，最后根据这些地下水动态研究结果提出了解决大同市水问题几项对策建议。本文的研究结果同时表明，地下水动态研究非常必要且现实意义明显。通过动态变化可以了解地下水的补排及储水介质的变化情况，利用动态变化规律可以预测水文地质条件的变化趋势，根据地下水动态变化特点可采取有针对性的、灵活的取水方案。可以说，地下水动态研究成果在水资源的开发、利用、保护中具有极大的可利用价值。     

A Simplified Analytical Procedure for the Determination of Organically Bound Halogens in Salt‐containing Water Samples

A method was developed for the determination of organic halogens in water samples with the aim of minimizing matrix effects and simplifying the sample preparation technique commonly used. The method is based on the adsorption of organic halogens in modified hydrophilic divinylbenzene polymer columns and their elution with methanol. The adsorbent used enables rapid adsorption and desorption due to comparatively high operating flow rates and minimized solvent amounts. Furthermore, no additional reconcentration steps are needed. The methanol extract obtained is combusted with a standard EOX (extractable organic halogen) analyzer and the concentration of organically bound halogens is determined by microcoulometric analysis. The matrix effects are considerably reduced compared to the standard procedure (EN 1485) commonly used. A detection limit of 13 μg/L was established.     

TRMM PR雷达与阜阳雷达降水资料的对比研究

选取了1998年与1999年HUBEX观测资料，将TRMM卫星上的星载降雨雷达PR与阜阳的713数字化天气雷达资料在以下3个方面做了比较：(1)强度场的分布；(2)平均反射率廓线；(3)灵敏度。分析、比较结果可知阜阳雷达在探测灵敏度和水平方向的分辨率要高于PR，但由于波束宽度、衰减和资料转化过程计算误差的原因，其远距离处的观测值与真实值有一定偏差。PR波长短，对衰减敏感，尤其是在垂直方向上经过强衰减后，订正值仍偏小。但由于探测方式的不同PR在水平方向上不存在衰减的问题，且其资料分布均匀，因此提出一种用PR资料来订正地基雷达资料的方法用以提高地基雷达探测的精确度。     

Measuring the k–S–p relations on DNAPLs migration

Migration characteristics of dense non-aqueous phase liquids (DNAPLs) in the subsurface can be expressed as a water–DNAPL two-phase system based on mainly the k–S–p relations, which describe the relations among relative permeability (k), degree of water saturation (S), and capillary pressure head (p). The aims of this research are to develop an experimental system with new type of probes, such as the electrical conductivity probe for measuring the degree of water saturation and the hydrophilic and hydrophobic tensiometer for measuring the pore water and DNAPL pressures, and also to estimate the results obtained from the developed experimental system. From these tests, the excellent k–S–p relations were obtained and the efficiency and validity of this developed experimental system have been confirmed in terms of the concept of the scaling coefficient calculated by interfacial tensions.     

Weather as a Chronic Hazard for Road Transportation in Canadian Cities

Inclement weather creates a chronic hazard for Canadian travellers. Past studies indicate that road collision rates increase during precipitation, although the magnitude of theincrease varies from study to study, partly as a result of variations in weather and driving conditions,but also because of differences in methods. The goal of the current study is to improve ourunderstanding of the links between weather and travel risk in mid-sized Canadian cities by using astandardized method for analyzing data from six cities with different climates: Halifax-Dartmouth,Ottawa, Québec, Hamilton, Waterloo Region, and Regina. The study has four interrelated objectives: (1) Toconduct a sensitivity analysis to determine the extent to which risk estimates vary depending onthe criteria used to define precipitation events and `normal' conditions; (2) To compare therelative risk of collision and injury during precipitation relative to `normal' conditions; (3) Todetermine the extent to which weather-related risks vary fordifferent Canadian cities; and (4) To explore any differences in collision characteristics between events and controls, especially as theyvary from city to city. Results are based on a matched-pair analysis, using six-hour time blocks over afour-year period, 1995 to 1998. Results indicate only modest sensitivity to the criteria used to define precipitation events and `normal' conditions. On average, precipitation is associated with a 75 percentincrease in traffic collisions and a 45 percent increase in related injuries, as compared to `normal'seasonal conditions, but risk levels vary depending on the characteristics of the weather event.Both sensitivity to specific weather conditions and weather-related accident profiles vary from city tocity in ways that are not easily explained.     

Hazard Zoning for Landslides Connected to Torrential Floods in the Jerte Valley (Spain) by using GIS Techniques

The Jerte Valley is anortheast-southwest tending graben located in the mountainous region of west central Spain (Spanish Central System). Mass movements have been a predominant shaping process on the Valley slopes during the Quaternary. Present day activity is characterized as either `first-time failure' (shallow debris slides and debris flows) or `reactivations' of pre-existing landslides deposits.A delineation of landslide hazard zoningwithin the Valley has been carried out by using the detailed documentation of a particular event (a debris slide and a sequel torrential flood, which occurred on the Jubaguerra stream gorge), and GIS techniques. The procedure has had four stages, which are: (1) the elaboration of a susceptibility map (spatial prediction) of landslides; (2) the elaboration of a map of `restricted susceptibility' in the particular case of slopes that are connected to streams and torrents (gorges); (3) the elaboration of a digital model which relates the altitude to the occurrence probability of those particular precipitation conditions which characterized the Jubaguerra event and (4) the combination of the probability model with the `restricted susceptibility map', to establish `critical zones' or areas which are more prone to the occurrence of phenomena that have same typology as this one.