北京昌平地震台TJ-1体积钻孔应变仪潮汐参数动态特征及其稳定性研究     

唐九安  王勇  刘福生 《华北地震科学》2001,19(4):34-40

介绍了北京昌平地震台 TJ- 1型钻孔体积应变仪 1 989年 7月～ 2 0 0 0年 1 2月期间的观测结果 ,分析了潮汐响应函数的动态特征及其稳定性。由全序列观测数据调和分析所得 :O1波潮汐因子 VO1=0 .791 6± 0 .0 1 2 8、相位滞后 ΔΦ0 1=1 .9°;K1波潮汐因子 Vk1=0 .6 4 42±0 .0 0 88、相位滞后ΔΦk1=- 4.2°;M2 波潮汐因子 VM2 =0 .6 5 0 0± 0 .0 0 3 8、相位滞后ΔΦM2 =-2 .9°。液态地核振荡因子 A=VO1/VK1=1 .2 2 8,比理论值小 6 .5 %。  相似文献   

动态模拟扫描成像转台转速系统变阻尼控制与PID控制的对比研究     

郑舒 《华东地质学院学报》2001,24(3):242-245

在设计高精度速率转台系统时，对PID控制与变阻尼控制作了对比研究，采用变阻尼控制方案较好地解决了系统快速性的矛盾，并且给出的仿真结果实验是令人满意的。  相似文献   

挖孔桩在长春市应用及承载力评定   总被引：1，自引：0，他引：1  

李向群  袁铁铮 《水文地质工程地质》2001,28(6):62-65,71

挖孔桩承载力的评价是国内、吉林省内重大课题，直接关系到它应用前景。本文试图结合国内现行诸规范，结合长春市实例，提出建议性意见，供广大设计者参考。  相似文献   

有关地形通视分析问题的研究和探讨     

田金蓉  汉斯 《测绘学院学报》1992,(3)

本文通过对地形通视分析的基本设想的描述及其实践途径中有关问题的探讨,结合实例阐明了计算机自动进行通视分析的基本方法和处理技巧,并附有具体程序。  相似文献   

冷水江煤矿塘冲矿井的地质采勘对比分析     

袁正泉 《湖南地质》1992,11(4):318-323

塘冲矿井的大量井巷地质资料与原勘探精查报告对比分析表明,原精查报告内容与实际情况有较大出入,特别是控煤褶皱、断裂,煤层厚度与储量等方面,都存在较大差异,对矿山采矿影响颇大。究其原因,可能是勘查阶段受规范和技术手段等的限制,使原报告精度不够。因此,本文提出改进勘探方法,完善规范,提高勘查精度和加强煤矿生产补充勘探,都显得十分重要。  相似文献   

Comparability of Biogenic VOC Emission Rate Measurements under Laboratory and Ambient Conditions at the Example of Monoterpene Emissions from Scots Pine (Pinus sylvestris)     

M. Komenda  K. Kobel  R. Koppmann  J. Wildt 《Journal of Atmospheric Chemistry》2003,45(1):1-23

Laboratory experiments under controlled environmental conditions are a useful tool to investigate the influence of different environmental parameters on VOC emissions from plants individually. Before using the obtained results to interpret measurements under ambient conditions, it has to be ensured that the laboratory system is suitable for performing emission rate measurements under ambient-like conditions to derive algorithms describing the emissions of volatile organic compounds as a function of physical variables like temperature and light intensity. Here we compare results from monoterpene emission rate measurements with Scots pines (Pinus sylvestris L.) under both ambient environmental conditions using a mobile plant enclosure chamber, and under controlled laboratory conditions in a continuously stirred tank reactor. The different analytical instruments to quantify monoterpene emissions were compared in an intercalibration experiment. Measurements of the mixing ratios of -pinene, -pinene, 3-carene, camphene, and limonene on the order of some hundred parts per trillion differed by less than 20%. The laboratory system has proven capable of providing ambient-like conditions and results of monoterpene emission rate measurements under laboratory conditions could be extrapolated to the natural environment. Monoterpene emission rate measurements with identical specimens of Scots pines conducted within small temporal differences under similar laboratory and outdoor conditions agreed well. Both laboratory and outdoor experiments clearly showed that distinct and constant values neither exist for the standard emission rates nor for the emission pattern of monoterpenes from Scots pine. Temporal variations in the standard emission rates from identical specimens and plant-to-plant variations were on the order of one magnitude.  相似文献   

玉龙斑岩铜矿含矿与非含矿斑岩元素和同位素地球化学对比研究   总被引：3，自引：3，他引：3  

姜耀辉蒋少涌  戴宝章凌洪飞 《岩石学报》2006,22(10):2561-2566

地质地球化学对比研究表明,玉龙含矿与非舍矿斑岩是由岩石圈地慢中交代成因的金云母-石榴石单斜辉石岩脉发生不同程度部分熔融而形成的。分矿斑岩是最早阶段熔融体,主要是由交代成因脉中副矿物(如磷灰石和碳酸盐矿物等)和舍水矿物金云母发生部分熔融而形成的,因而富含 F、Cl 和水等挥岌份,加上该阶段岩浆具有高氧化性特征,从而富含 Cu 等成矿元素;非含矿斑岩是交代成固咏相对较高熔融程度的产物,单斜辉石和石榴石介入了熔融作用,岩浆熔体相对贫乏F、Cl 和水等挥发份,加上该阶段岩浆具有较低的 f_(0_2),从而不利于成矿。斑岩体全岩的 F 和 Cl 含量(舍矿斑岩 F>1200 ppm,Cl>150 ppm;非含矿斑岩 F<1200 ppm,Cl<150 ppm)、K_2O/Na_2O(含矿斑岩>1.2,非含矿斑岩<1.2)和 Sm/Yb(含矿斑岩>6.5,非含矿斑岩<6.5)比值以及黑云母中的 Fe~(3 )/Fe~(2 )比值(含矿斑岩>0.7,非舍矿斑岩<0.7)是区分含矿与非含矿斑岩的重要地球化学参数。含矿斑岩与非分矿斑岩具有非常相似的 Sr-Nd-Pb 同位素组成,,表明含矿与非含矿班岩具有相同的源区。  相似文献   

河西走廊春季强冻害成因及防御对策     

罗晓玲  郭良才  兰晓波 《沙漠与绿洲气象(新疆气象)》2006,29(3):20-21

应用酒泉、张掖、武威实况资料,从作物的各个生长发育期进行了对比分析,结果表明强冷空气爆发是造成冻害的直接原因,前期气温异常偏高使农作物生育期提前、气温和地温较低加剧了冻害程度。并提出了防御冻害发生的有效措施。  相似文献   

Galileo和GPS的几点比较     

田晓振  陈正阳  冯光财  郝卫峰  王潜心 《测绘信息与工程》2007,32(1):41-43

利用GSSF 2.0软件模拟出Galileo系统全球范围的卫星可见性、GDOP、TDOP、PDOP、HDOP、VDOP值,并与GPS进行了比较。  相似文献   

Comparison of 15 evaporation methods applied to a small mountain lake in the northeastern USA   总被引：7，自引：0，他引：7  

Donald O. Rosenberry  Thomas C. Winter  Donald C. Buso  Gene E. Likens   《Journal of Hydrology》2007,340(3-4):149-166

Few detailed evaporation studies exist for small lakes or reservoirs in mountainous settings. A detailed evaporation study was conducted at Mirror Lake, a 0.15 km² lake in New Hampshire, northeastern USA, as part of a long-term investigation of lake hydrology. Evaporation was determined using 14 alternate evaporation methods during six open-water seasons and compared with values from the Bowen-ratio energy-budget (BREB) method, considered the standard. Values from the Priestley–Taylor, deBruin–Keijman, and Penman methods compared most favorably with BREB-determined values. Differences from BREB values averaged 0.19, 0.27, and 0.20 mm d⁻¹, respectively, and results were within 20% of BREB values during more than 90% of the 37 monthly comparison periods. All three methods require measurement of net radiation, air temperature, change in heat stored in the lake, and vapor pressure, making them relatively data intensive. Several of the methods had substantial bias when compared with BREB values and were subsequently modified to eliminate bias. Methods that rely only on measurement of air temperature, or air temperature and solar radiation, were relatively cost-effective options for measuring evaporation at this small New England lake, outperforming some methods that require measurement of a greater number of variables. It is likely that the atmosphere above Mirror Lake was affected by occasional formation of separation eddies on the lee side of nearby high terrain, although those influences do not appear to be significant to measured evaporation from the lake when averaged over monthly periods.  相似文献