南海西部浮游有孔虫记录的MIS 3期表层海洋环境变化

对南海西部越南岸外上升流区17954-2站浮游有孔虫属种组合变化、浮游有孔虫氧同位素、AMS14C测年的分析以及浮游有孔虫表层海水温度、温跃层转换函数的研究结果表明:在MIS3期,南海西部表层海水温度大体呈现暖-冷-暖的变化趋势;温跃层深度由浅到深阶段性变化;短时间尺度上温度与温跃层发生幅度较大的快速变化。暖事件（IS）对应于浮游有孔虫暖水种、混合层属种含量的增加,冷水种、温跃层属种含量的减少以及冬夏SST的升高;冷事件则与之相反。表层海水生产力亦大致呈现3个阶段（61～51ka,51～42ka和42～32ka）的变化,在千年尺度的快速气候事件中,暖事件对应浮游有孔虫生产力属种含量降低,冷事件对应升高。此外,在MIS3内部分暖事件（IS6和IS11～13）表现出表层海水温度降低,温跃层深度变浅和表层海水生产力升高的状况,表明该区此时上升流的存在,其形成原因推测是由于东亚夏季风加强的结果。     

基于小波变换的单频GPS快速精密定位整周模糊度的解算

对于GPS短基线,载波相位双差观测量已基本消除了卫星轨道误差、钟差、大气折射误差等系统偏差的影响,主要包含距离观测量信息及随机测量误差,其中测量误差是高频的测量噪声,小波变换可将GPS载波相位双差观测量中的观测噪声(高频部分)分解出来。本文利用Coiflets小波基函数对GPS快速定位的原始载波相位双差观测量进行5层分解,通过重构第5层低频系数获得去除噪声的"干净"的载波相位双差观测量,然后利用"干净"的双差观测量进行最小二乘参数估计,以减小测量噪声对GPS快速定位病态方程解的扰动。计算结果表明该方法能够显著提高GPS快速定位中模糊度浮点解的精度,仅利用几个观测历元的数据就可以准确地固定模糊度。     

合肥遥测台网地震速报系统

论述了适用于遥测地震台网大震速报的一套计算机处理系统,系统设计以《全国遥测台网观测技术规范》和《近震分析》理论为依据,实现了数据输入,震相选择,数据处理,地震定位,震级计算,结果输出及贮存等多项功能,达到了快速确定地震三要素,提高速报速度和精度之目的,是一个较完善的,实用的速报系统。     

湿地功能快速评价中的若干理论问题

针对目前湿地功能快速评价中存在的不足之处,分析了产生这些不足的原因及湿地功能快速评价过程中存在的一些基本理论问题。分析表明:湿地功能快速评价方法是为了达到“湿地功能无净损失”目的,是在需要评价的湿地如此之多而从事湿地功能评价的专业人员又极其缺乏的情况下发展起来的。它对于湿地恢复与重建以及湿地受人类活动干扰程度的评价是非常有效的;在湿地功能快速评价过程中,把相对未受人类干扰的参照湿地的功能指数规定为1,这就使得快速评价方法不能对参照湿地的功能进行评价,而目前最需要评价其功能的湿地往往就是这些相对未受人类活动干扰的湿地;在相同水文地貌的湿地类型内评价湿地功能之间的差异,这使得快速评价方法不能评价湿地的水文地貌功能;由于快速评价的结果都是相对的功能指数,并不能说明湿地所提供的功能量是否满足人们的需求,因而在决策中不能单独使用;快速评价都是“一次调查就获得结果”,同时由于快速评价过程中指标选择的主观性、指标赋值的主观性、采样点空间设置的主观性以及采样时间的主观性,对于具有时空变化特征的湿地功能的评价结果的可重复性和科学性是很低的。为了使湿地功能评价的结果对管理和决策具有指导意义,基于湿地功能量计算的、定量的评价湿地功能的方法必须开发出来。针对不同的评价目的,湿地功能评价可采用双重参照标准:一是以自然为参照来评价湿地功能受人类活动影响的程度以及湿地恢复与重建成功与否;二是以人类需要为标准来评价湿地提供的功能量是否满足了我们的期望,以便采取措施改进湿地功能来满足人类的需求。     

砂岩型铀矿勘查样品中铀的野外快速测定方法研究

本文研究并建立了适合野外条件下快速测定砂岩型铀矿勘查试样中铀的分析方法———密闭酸溶试样、钒酸铵容量法测定铀。采用密闭增压酸溶样, 可使粒度小于0 25 mm的试样分解完全;小体积容量法提高了测定灵敏度。配合不同浓度的标准溶液可适应不同含量范围铀的测定。方法经标准物质和吐哈工区试样验证, 准确度和精度较高, 且操作简单, 适应性广, 具有实用和推广价值。     

数字遥测地震台网地震速报中文平台

叙述了数字遥测地震台网地震速报中平台程序基本流程和使用特点，程序采用Vi编程方法实现以二维坐标点阵结构显示汉字，与台网的交互软件（EDSP-IAS）中的WaveView程序自动链接运行，该闰台界面操作方便直观，易于定位地震参数，自动速报上网和自动寻呼。     

Screening model for volatile pollutants in dual porosity soils

This paper develops mass fraction models for transport and fate of agricultural pollutants in structured two-region soils. Mass fraction index models, based on a semi-infinite domain solution, are derived that describe leaching at depth, vapor losses through soil surface, absorption, and degradation in the dynamic- and stagnant-water soil regions. The models predict that leaching is the result of the combined effect of the upward vapor-phase transport relative to downward advection, residence time relative to half-life, dispersion, and lateral diffusive mass transfer. Simulations show that leached fraction of volatile compounds does not always decrease monotonically with increased residence time relative to the pollutant half-life, as a result of complex interactions among the different physical and biochemical processes. The results show that leaching, volatilization, and degradation losses can be affected significantly by lateral diffusive mass transfer into immobile-water regions and advection relative to dispersion (i.e. Peclet number) in the mobile-water regions. It is shown that solute diffusion into the immobile phase and subsequent biochemical decay reduces leaching and vapor losses through soil surface. Potential use of the modified leaching index for the screening of selected pesticides is illustrated for different soil textures and infiltration rates. The analysis may be useful to the management of pesticides and the design of landfills.     

全球不同纬度带平均有效位能的季节急变

利用1980～1988年ECMWF的资料，计算了对流层500 hPa、300 hPa和平流层100 hPa逐日和月平均的纬向平均有效位能（PZ），分析其季节过渡，比较不同纬度带的季节性急变。结果表明，在4月和10月附近，各纬度带上均可出现PZ的急变。而且用逐日资料还可分析出6月急变。在北半球对流层高层（100 hPa）PZ的季节性急变不如低层（500 hPa）明显，而在南半球PZ的季节性急变与北半球相反，高层比低层明显。     

Rapid cooling and exhumation of eclogitic rocks from the Great Caucasus, Russia

Diffusion modelling of growth-zoned garnet is used in combination with standard geothermometric and geobarometric techniques to estimate cooling and denudation rates from the mafic eclogites of the Red Cliff area, Great Caucasus, Russia. Euhedral garnet porphyroblasts exhibit different degrees of prograde growth zoning depending on the size of the grain (100 μm to several mm in diameter). Zoning patterns are mainly expressed in terms of Fe–Mg exchange, with 100*Mg/(Mg+Fe) increasing from 18–20 to 33–37 from core to rim. Geothermobarometry yields conditions of 680±40 °C and a minimum of 1.6±0.2 GPa and of 660±40 °C and 0.8±0.2 GPa for the high-pressure and retrograde stages of equilibration, respectively. A temperature of 600±40 °C has been recorded for the late-stage metamorphic overprint in the mica schists surrounding the eclogites. Relaxation of garnet zoning profiles was modelled for three different hypothetical P–T –t trajectories, all with an initial temperature of 680 °C and a pressure change of 0.8 GPa. The first two trajectories involve decompression associated with regular cooling down to 660 °C (near isothermal) and 600 °C. The third path is a two-step trajectory comprising near-isobaric cooling down to 600 °C followed by isothermal decompression to 0.8 GPa. These P–T trajectories cover as wide a range of pressure and temperature changes endured by the rocks as possible, thus representing extreme cases for calculating cooling and exhumation rates. Calculations indicate that the zoning pattern of the smallest garnet (i.e. garnet for which the zoning is most easily eliminated during post-growth processes) along the different paths can be preserved for the following average exhumation and cooling rates: path 1, 143 mm a^?1 and 102 °C Ma^?1; path 2, 60 mm a^?1 and 171 °C Ma^?1; path 3, 11–30 mm a^?1 and 200–400 °C Ma^?1. These results are discussed in light of theoretical P–T–t paths extracted from thermal models of regions of thickened crust, and from analogue models of accretionary wedge and continental lithosphere subduction.     

祁连山地区1310年以来湿润指数及其年际变幅的变化与突变分析

本文通过用树木年轮资料重建的祁连山地区5～7月份1310年以来的湿润指数序列，建立了一个反映该地区湿润指数年际变幅序列，对这两个序列分别进行了等级分类和干湿、强弱的时段分析，并用最大熵谱分析法对这两个序列的不同时段分别进行了周期分析。采用HK突变检验方法对这两个序列分别进行了突变分析，发现祁连山地区的湿润指数及其年际变幅存在明显的突变年份。