某铀矿工人头发中总α,总β,铀,钍放射性水平的调查

本文对某铀矿职业工人和非职业工人头发中的总β、总α放射性水平和铀、钍含量进行了分析测定.结果表明,该矿工人体内铀和钍的蓄积量均在正常放射性本底水平范围内,从头发中检验未观察到工人体内铀、钍放射性水平有明显的升高.     

电子设计竞赛与大学生创新能力培养

本文探讨了大学生电子设计竞赛对促进实践教学的重要作用，电子设计竞赛对大学生创新能力培养的作用，论述了高校深化实践教学改革与培养学生创新精神、创新能力的必要性。     

炼油厂污水处理负荷的削减措施

总结和分析了某厂削减污水处理负荷的主要措施及效益，预测该厂在达到16000kt/a以上加工规模时的污水处理负荷。     

A juvenile coelurosaurian theropod from China indicates arboreal habits

Here we report an unequivocal arboreal coelurosaur, Epidendrosaurus ningchengensis gen. et sp. nov. This juvenile coelurosaur's third manual digit is extremely elongated, distinctively different from that of other known dinosaurs and birds. It represents certainly a type of adaptation previously unreported from the Mesozoic although the exact function of the third manual digit is unclear. The relatively long forelimb, penultimate phalanx of manual digit II, and pedal penultimate phalanges, are interpreted as evidence for the arboreal habit of Epidendrosaurus. Because Epidendrosaurus is more similar to advanced birds in some arboreal features than to Archaeopteryx, we suggest that the initial appearance of tree-adaptation in theropods was probably not directly related to flight but to other functions, such as seeking food or escaping from predators. Electronic Supplementary Material is available if you access this article at http://dx.doi.org/10.1007/s00114-002-0353-8. On that page (frame on the left side), a link takes you directly to the supplementary material.     

新疆宝浪油田污水达标回注技术应用

新疆宝浪油田污水处理原来采用外排方式,严重污染了周边环境。为此,通过对处理工艺进行的改进,对分散自控系统的升级改造及对处理药剂进行了重新筛选。改造后终端出口水质的悬浮物由200 mg/L下降到3.93 mg/L,去除率为96%,含油量由200 mg/L降为0.79 mg/L,去除率为99%,含铁为3.9 mg/L,细菌总数为4.5个/mL,硫酸盐还原菌为4.5个/mL,处理后的污水水质达到了《碎屑岩油藏注水水质推荐指标及分析方法》标准回注要求。     

显微构造分析法和包裹体方法在断层研究中的应用

在工程建设中，工地及邻近地区的断层活动性是工程设计的一项重要依据。在总结以往研究的基础上，介绍了显微构造分析法和包裹体方法在断层活动性评价中的国内外最新研究成果。事实表明，这两种方法在工程地质领域具有良好的应用前景。     

A COMPARATIVE STUDY OF A SWEDISH AND A CHINESE HYDROLOGICAL MODEL1

ABSTRACT: There are a large number of conceptual hydrological models available today. It is not easy to immediately identify the similarities and differences between the different models. The Swedish HBV model and the Chinese Xinanjiang model are two examples of conceptual, semi-distributed, rainfall-runoff models. The Xinanjiang model was designed for use in humid and semi-humid regions, with no routine for the snowmelt runoff, whereas the snow routine is an important part of the HBV model in many applications. The model structures of the two models may be described in four routines, compared in this paper. The integral structures of them are similar, but there are some differences, especially in the runoff production routine. The physical significance and physical definitions of some model parameters were analyzed. Both models were tested in two basins. Both models gave similar results, and both models performed well in the application. The similarity of the results obtained by different model structures leads to the following two conclusions. First, more effort should probably be spent on the improvement of input data quality and coverage than on the development of more detailed model structures only. Second, inference about basin behavior and characteristics from the values of calibrated model parameters must be made with great caution.     

用灰色模型预测我国铁路水害发展趋势

根据近１５ａ来我国铁路水害年断道时间和断道次数的数据特点，将不同程度水害年分为三个等级。在此基础上，建立了铁路水害的灰色预测模型。并用此模型预测了近期铁路水害大小和远期的发展趋势。这对于我国铁路水害防治的宏观决策具有指导意义。     

Tillage erosion and its effect on soil properties and crop yield in Denmark

Tillage erosion had been identified as a major process of soil redistribution on sloping arable land. The objectives of our study were to investigate the extent of tillage erosion and its effect on soil quality and productivity under Danish conditions. Soil samples were collected to a 0.45-m depth on a regular grid from a 1.9-ha site and analyzed for 137Cs inventories, as a measure of soil redistribution, soil texture, soil organic carbon (SOC) contents, and phosphorus (P) contents. Grain yield was determined at the same sampling points. Substantial soil redistribution had occurred during the past decades, mainly due to tillage. Average tillage erosion rates of 2.7 kg m(-2) yr(-1) occurred on the shoulderslopes, while deposition amounted to 1.2 kg m(-2) yr(-1) on foot- and toeslopes. The pattern of soil redistribution could not be explained by water erosion. Soil organic carbon and P contents in soil profiles increased from the shoulder- toward the toeslopes. Tillage translocation rates were strongly correlated with SOC contents, A-horizon depth, and P contents. Thus, tillage erosion had led to truncated soils on shoulderslopes and deep, colluvial soils on the foot- and toeslopes, substantially affecting within-field variability of soil properties. We concluded that tillage erosion has important implications for SOC dynamics on hummocky land and increases the risk for nutrient losses by overland flow and leaching. Despite the occurrence of deep soils across the study area, evidence suggested that crop productivity was affected by tillage-induced soil redistribution. However, tillage erosion effects on crop yield were confounded by topography-yield relationships.