X射线形貌术概述

文章概略介绍了Ｘ射线形貌术以及其实验原理和方法,并对影响图象分辩率和质量的主要因素作了扼要分析。     

北黄海大鹿岛附近海域海洋牧场本底地质环境分析

为推进北黄海北部特色滩涂型海洋牧场建设,本研究对北黄海大鹿岛附近海域海洋牧场本底地质环境开展调查评估,利用高分辨率声学探测设备获取研究海域的精密水深数据和浅地层剖面数据;利用现场和实验室结合的方法测定海水理化参数;利用筛析法、激光粒度仪测试方法确定沉积物类型和粒度特征,最终通过分析研究区海底地形地貌、海水水质状况和沉积物分布特征对本底地质环境进行评估。结果显示：目标海域测量水深为1-29 m,平均水深为16 m,海底地形整体表现为平缓的近岸缓坡,地貌以水下侵蚀堆积地貌为主;海底浅地层剖面中U1声学地层清晰连续,全区可追踪,厚度约6 m且变化不大;海水水质良好,主要处于Ⅱ类海水水质标准;表层沉积物类型均为砂,沉积物组分变化不大,砂组分占绝对优势,表层沉积物空间分布主要与沉积物物源条件及辽南沿岸流、海域潮流等因素有关。综合分析认为,北黄海大鹿岛附近海域水深适宜,地形较为平坦,水质环境良好,以砂质浅滩沉积为主,适于滩涂型海洋牧场的构建。     

大兴安岭北端地形因子对针叶林土壤黑碳储量的影响

[目的]气候变化对人类社会发展产生的影响受到了世界各国的广泛关注,提高森林生态系统的固碳潜力被认为是经济可行且有效减缓大气二氧化碳(CO2)浓度的重要途径之一,大兴安岭地区森林生态系统的黑碳储量在全球碳循环和碳汇方面具有重要的作用.研究大兴安岭不同地形因子条件下土壤黑碳的储藏分布特征,为区域森林土壤黑碳储量准确估算和森...     

Numerical simulation of topography effects on the "00.7" severe rainfall in Beijing

In an effort to study the severe rainfall event of 4-5th July 2000 in Beijing (with 24h accumulated precipitation of 240 mm), we perform numerical simulations to investigate this event using the MM5v3.6 model. The model is initialized with the MM5/WRF 3DVAR analysis, which incorporates the ground-based GPS precipitable water vapor, automatic and conventional meteorological observations in its assimilation step. For 24 h accumulated precipitation forecast, the threat scores are 0.72, 0.76, 0.67 and 0.63, for thresholds of 1, 5, 10, and 20 mm, respectively. Holding other factors unchanged, sensitivity experiments were conducted with different topographic resolutions of 110, 50 and 3.7 km to investigate the topographic effects on precipitation over the Beijing area. In these sensitivity experiments, we attempt to preserve the realistic orographic distribution in the model topography under the condition of keeping the dynamic-thermodynamic consistency of the initial model atmosphere to the extent possible. Results indicate that the unique topographic distribution and variations in the Beijing area play an important role in determining the location, distribution and intensity of heavy precipitation.     

数字地形分析系统(DTAS)的设计

本文应用文献[1]和[7]的算法建立DTAS,设计DTAS软件,并应用DTM数据进行试验,获得了多种地形参数,并自动绘制出各种地形条件图。     

复杂地表区波动方程基准面校正方法

在分析波动方程基准面校正原理的基础上,提出了“相移一时移法”波场延拓算法,将相移算子分解为偏移算子、延拓算子和时移算子,并修改了Stolt公式,使得波动方程基准面校正能适应地表起伏剧烈、近地表速度纵横向变化剧烈的复杂地表条件。用编写的软件对复杂地表区的实际资料进行了试算,处理结果表明,用“相移-时移法”进行波动方程基准面校正能很好地消除起伏地表和复杂地表结构对数据的影响,为速度分析和同相叠加奠定良好的基础。     

可溶性聚吡咯的研究

用氰化聚合法制备了具有导电性能的自掺杂可溶性聚３－丁酸基吡咯，并对它进行了红外光谱、掺杂性能及表面形貌的测试和表征。     

EFFECT OF N~+ ION IMPLANTATION ON SURFACE ROUGHNESS OF 40Cr STEEL

The different change tendencies of 2-and 3-dimensional surface roughnesses of 40Cr steel aremeasured and analysed.In 2-dimensional parameters,the data are measured amplitude parametersR_a ,R_q ,R_(pn),spacing parameters S_m,S,q and shape parameters Δq,T_p %,R_(sk),R_(ku)..In3-dimensional parameters,the similar amplitude and shape parameters are measured.The au-thors found that ion implantation lcads to reduction of the values of the amplitude parameters ofthe surface roughness remarkably.The values of the spacing parameters have no regular changes.The changes of surface profiles before and after ion implantations have been measured in detail.Inaddition,the auto-correlation function and the power spectrum are analysed for the surfaces ofdifferent implanting parameters.It is concluded that in the observed frequency range,the intensi-ties of various frequencies decrease widely and the coefficients of the auto-correlation of surfacesdecrease after ion implantation.     

在动床试验中试用二种不同比重的模型沙

本文提出在水力枢纽局部冲刷与建筑物边坡稳定的水工模型试验中试用木屑（重率１．１ｔ／ｍ３）和天然沙（重率２．６５ｔ／ｍ３）分别模拟级配较宽的原河床推移质中的细、粗颗粒，选沙设计重点考虑影响抗冲稳定的粗颗粒（ｄ７５）；同时，按不同要求的模拟部位分别采用与上述模型沙对应的冲淤时间比尺施放模型水流，获得所需范围的冲淤地形。经水口水电站大江度汛与截流工程现场观测验证，模型之冲淤地形变化趋势、高程，截流龙口抛投材料粒径、数量以及导流明渠和龙口的各项水力参数与原型相当吻合。