地图设色系统中颜色转换模型的研究

本文详细地推导了由CRT上的颜色等色转换为YMC 颜色方程,并给出了具体的形式及其结果。同时,对同包转换的条件进行了讨论,指出了颜色转换方程的适用条件,得到了一些有价值的结论。     

1991—1992年ENSO事件的特征

根据美国国家海洋大气局气候分析中心（ＣＡＣ）和中国气象局气候监测公报所提供的海－气资料，综合分析了１９９１－１９９２年ＥＮＳＯ事件的形成、发展过程。这次ＥＮＳＯ事件的主要特点是：①在ＥＮＳＯ事件爆发前一年内热带太平洋海气特性频频呈现异常，暖水堆积在赤道中太平洋（５°Ｎ－５°Ｓ，１６０°Ｅ－１６０°Ｗ）约１２个月，然后自西向东传输，爆发１９９１－１９９２年ＥＮＳＯ事件。②对ＥＮＳＯ事件作出响应的西太     

Geochemistry of dissolved and particulate elements in the major rivers of China (The Huanghe,Changjiang, and Zhunjiang rivers)

The relationship between the geochemistry of dissolved and particulate materials and geographic conditions was investigated. Samples of water and suspended particulate matter were collected from five locations in three of the major rivers of China (the Huanghe, Changjiang, and Zhunjiang rivers). Because these rivers generally flow parallel to latitudes and flow through diverse geologic and climate zones, they provide excellent opportunities for comparisons of solute transport. The geochemistry of these rivers is influenced strongly by climate. The low discharge of the Huanghe River influences the character of the major ionic materials (Cl^?+SO₄ ^2? and Na⁺+K⁺) as well as the high degree of mineralization within the system. Dissolved concentrations of both major ions and trace elements are lower in the southern reaches of the rivers. The highly mobile ions, such as, Na⁺ and Ca²⁺, are depleted from the suspended particulate material in the southern regions, while the relatively immobile ions of Al, Fe, Ti, Mn, and trace metals are concentrated within the suspended mateiral. The relative mobility of some elements as measured by the Dissolved Transport Index (DTI) changes with climate. The geology of the area drained by the rivers has a major influence on the geochemistry in areas of similar climate. Lowest leaching rates in the southern climates occur in areas dominated by granite, which is resistant to weathering. The composition of both cations and anions among the three tributaries of the Zhujiang River are dependent on the rocks that dominate each eregion. Some particulate forms of the rare earth elements are present in the highest concentrations in regions dominated by granite. The DTI calculated for the major rivers in China are much smaller than those computed for other major rivers of the world. The low concentration of heavy metals in the particulate material suggests that pollution in the rivers of China is less serious than in rivers of other industrialized countries.     

强火山爆发与厄尼诺事件

前人研究指出,强火山爆发时,把大量火山灰喷入平流层。0.5—1年内即可扩展到全球,它可以使全球平均气温下降0.5℃。本文主要揭示了近34年来,强火山爆发使全球平均气温降低这一微弱信息,经过大尺度海气相互作用调节、放大之后,使西太平洋副热带高压、赤道辐合带、北太平洋海温距平场转折,并容易发生厄尼诺的规律性。指出强火山爆发可能是厄尼诺发生的重要原因之一。     

J—A2500射频发生器及其维修

本文介绍J-A2500射频发生器的简单工作原理、调试方法和典型故障排除以及使用维修注意事项。     

乌鲁木齐河流域的水资源及其转化模型

根据我国西北干旱内陆流域水资源形成、转化规律和水资源利用实际情况,利用乌鲁木齐河流域较为丰富的地表水和地下水资料,并结合流域水文地质条件,研制了乌鲁木齐河流域水资源转化模拟和计算模型。模拟和计算结果表明,乌鲁木齐河流域现状实际引水量和净用水量,已经大大超过现有水利条件下的最大可能引水量和净用水量,其中净用水量甚至超过了流域的水资源总量,水资源开发利用明显过度。在现有情况下,再采用提高渠系利用率方法增加可用水量,效果甚微,只能通过节水途径,提高水的利用率,去建立新的水资源供需平衡。     

自记水位仪的数字化改造

本文详细叙述了采用光电编码和微机技术对自记水位仪进行数字化改造的方案选择、理论计算和改造实践。