水中硫酸盐测定方法研究

对EDTA容量法测定水中硫酸根时，对加入沉淀剂后样品静置时间对测定结果的影响进行了研究。结果表明，在本法规定的浓度范围内，样品静置时间对测定结果无影响。     

＂铁路运输＂教学过程设计

一、创设情境,导入新课 课前,循环播放自制铁路运输景观的PPT。（分发上海一杭州的列车时刻表）     

DAS技术在油气地球物理中的应用综述

光纤分布式声波传感技术(DAS)基于相位敏感光时域反射,是一种利用光纤后向瑞利散射干涉效应实现声波信号连续分布式探测的新型传感技术.在油气勘探开发领域,近年来在井中VSP、地表地震采集、时延或永久油藏监测、水力压裂监测等方面开展了试验和应用,取得了初步的成功.相比常规地面检波器及井中检波器,DAS技术具有低成本、高效率...     

煤层中瑞利型导波的能量分布

为了研究瑞利型导波在煤层中的能量分布规律,理论推导了3层对称弹性介质中瑞利波的频散曲线方程以及瑞利型导波的能量分布方程;绘制振幅深度分布曲线。研究表明,煤层中传播的瑞利型导波其能量主要集中在煤层中,且其能量在煤层中分布遵循一定的规律,即：瑞利型导波的x分量的能量关于煤层中心偶对称,且煤层中心能量最强;z分量关于煤层中心奇对称,且煤层中心能量最小。     

“新罗马”的前世今生——君士坦丁堡地图

君士坦丁堡,即今土耳其的最大城市和港口伊斯坦布尔,公元330年由罗马皇帝君士坦丁大帝仿照罗马城营建,位于博斯普鲁斯海峡西岸的金角湾与马尔马拉海之间,跨越欧亚两大洲,控扼欧亚往来通道和爱琴海与黑海的唯一通路,在历史上曾经作为罗马帝国、拜占庭帝国、拉丁帝国和奥斯曼帝国的首都,中世纪时长期是欧洲规模最大、最繁华的城市和欧洲人抵御东方波斯人、阿拉伯人和土耳其人的堡垒,因而成为欧洲城市图的重点描绘对象.     

化马成洲—文艺复兴时期的《飞马亚洲地图》

15世纪后半叶的欧洲,文艺复兴运动如火如荼,人文主义精神郁然勃发。欧洲的制图家们跳出中世纪宗教神学的藩篱,一面回首过往,从古希腊罗马文明中汲取思想遗产;另一面展望未来,吸收“大航海时代”最新的世界地理知识：再加上印刷术的改良,这样欧洲地图的绘制迈入一个全新的时代。     

2008年汶川M_S8.0地震后GPS资料反映的龙门山断裂带南段地壳水平变形动态特征分析

本文对龙门山断裂带南段GPS位移时间序列进行了欧拉基准转换、最小二乘配置插值和滤波分析等数据后处理,并利用块体刚性-弹塑性运动-应变模型计算了龙门山南段各区域应变参数时间序列。结合各站点位移时间序列、速度场及各区域应变参数序列,分析发现2008年汶川MS8.0地震对龙门山南段的影响由西北至东南由大变小,引起最大变形速度达背景速度6倍,增强了隐伏断层对两侧地表影响的差异,使南段的地震危险性由北至南增加。根据龙门山南段的历史地震及构造背景,对各区域地震危险性进行了比较,发现东南侧危险性最大,历史应变的积累及汶川地震的加速影响导致了芦山地震的提前发生和破裂断层的左旋错动。汶川地震对较远的鲜水河断裂南段也有持续两年的应力微释放影响,但其远不及川滇块体的应力压缩作用。     

GIS技术在生态环境地质评价中的应用研究

GIS(Geographic Information System)即地理信息系统,它作为一种特殊的空间信息系统可有效应用于对地球表层空间的相关数据技术分析进程中,对数据进行采集、存储、管理、运算、分析、显示和描述。本文结合GIS技术研究了它在生态环境地质评价中的具体应用,从它的评价思路、技术路线、评价方法以及综合评价预测等多方面展开分析,证明GIS技术在该领域中的应用技术优越性。     

DEVELOPMENT AND ASSESSMENT OF QUANTITATIVE PRECIPITATION ESTIMATION ALGORITHMS FOR S-, C-, AND X-BAND DUAL-POLARIZATION RADARS BASED ON DISDROMETER DATA FROM THREE REGIONS OF CHINA

The accuracy of quantitative precipitation estimation (QPE) for dual-polarization radars can be improved by using a localized rainfall estimation algorithm derived from the raindrop size distribution (DSD). In the present study, DSDs observed at Suzhou City, Jiangsu province; Yangjiang City, Guangdong province; and Naqu City, Tibet are analyzed during the rainy season together with the corresponding polarimetric variables for the above three regions. Most importantly, these DSD data are used to develop optimal “synthetic” QPE algorithms for S-, C-, and X-band dual-polarization radars, which will be built or upgraded in the three regions. Meanwhile, a new piecewise fitting method (PFM) is proposed. It has been found that the number concentration N(D) of small raindrops (D<1mm) is the highest in Suzhou, while that of larger raindrops (D>1mm) is the highest in Yangjiang. The characteristics of the differential reflectivity (ZDR) and specific differential phase (KDP) are significantly different in the three locations, suggesting that different rainfall estimators are needed for different locations. Further performance assessment of the QPE based on DSD data indicates that the PFM QPE algorithm (LDSD) performs better than the conventional fitting method (CFM), and the localized QPE algorithm can improve the QPE accuracy. Observations from S-band dual-polarization radars and rain gauges in the Southern China Monsoon Rainfall Experiment are implemented to verify the performances of the QPE algorithms proposed in the present study. It is found that compared with non-localized algorithms, the localized LDSD algorithm yields the best results with at least 7.66% and 8.43% reductions in the RMSE and NE, respectively, which implies that while polarimetric variables can reflect DSD characteristics, the localized QPE algorithm remains necessary.