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1.
针对形变观测数据振幅非均匀变化的情况,分别采用最小二乘法、基于F检验的分段最小二乘法及滑动傅里叶法进行年周期拟合,通过比较拟合残差分析各种方法的优劣和适用性。结果显示,在年周期振幅不变或渐变的情况下,3种方法拟合效果均较好,滑动傅里叶拟合略优于其他两种方法;在年周期振幅变化复杂且存在相位差的情况下,分段最小二乘法明显最优,但在分段点会产生阶跃及周期不连续的现象。  相似文献   

2.
利用丹江口无线传输地震台网选勘资料,进行最小二拟合,得到在给定无线传输设备仪器条件下,接收端无线电波场强估算的经验公式为 E_o(db)=1.55F(U)-20log△+151.0(±5.6)  相似文献   

3.
Trare amounts of benzene hydrocarbons obtained in Jiaozhou Bay (Qindao) were enriched bysorption on a GDX-102 column and eluted by carbon disulfide. The eluted was concenttaled and then de-temened by capillary column gas cbornatognphy.The contents of virious kinds of benzene hydrocarbons in Jiaozhou Bay coastal water were benzene(22.3-141.6)× 10~(-9)g/L, toluate (15.2-94.0) × 10~(-9) g/L, ethyl benzene(11.8-85.1)×10~(-9) g/L, p -xylene(15.2-78.5) ×10(-9) g/L, m-xylene (10.9-79.4) ×10(-9) g/L, o -xylene (12.4-80.1) x ×10(-9)g/L; iso-propyl(8.4- 73.1) x ×10(-9)g/L, n -propyl (6.9-76.4) ×10(-9) g/L, 1, 3, 5-trimethylbenzene (10.9- 35.9)×10(-9) g/L, 1,2, 4-trimethybenzene (10.0- 38.0)×10(-9) g/L, n - butydriare (8. 1 - 34.6) ×10(-9)g/L. The recovery of benzenehydrocarbons was (85.1 -95.6)%.  相似文献   

4.
本文用细化了的重力和地形综合数学模型、双层锯齿形计算模板、给定区域方差—协方差函数的最小二乘配置小区域内插和精度限定等精算重力异常场值的方法,以不低于±2.4×10~(-5)ms~(-2)和±2.9×10~(-5)ms~(-2)的精度,分别获得了滇西试验场区(99°E~102°E,24°N~27°N)最新完全布格重力异常和均衡重力异常展布图。依该区地震分布与重力场变异特征的对比研究,将下关—洱源—剑川一线划为7~7.5级地震潜在源区,永胜—大姚北划为6.5—7级地震潜在源区。  相似文献   

5.
植物样品在500℃灰化,用硝酸、氢氟酸和高氯酸分解,然后在2%的盐酸介质中,用火焰原子吸收分光光度法测定植物样品中的微量铜。该方法简单、快速、准确。方法的检出限为0.55×10~(-6),回收率97%—102%。对含量为5.14×10~(-6),9.43×10~(-6)和17.63×10~(-6)的三个植物样品进行分析,其相对标准偏差分别是4.62%、4.22%和2.00%。  相似文献   

6.
南阳黄牛体重曲线拟合的比较分析   总被引:1,自引:0,他引:1  
根据河南省南阳市黄牛良种繁育场的生产记录,利用Brody、Von Bertallanffy、Gompertz和Logistic 4种生长模型,对南阳黄牛母牛体重生长发育过程进行拟合比较分析。结果表明:VonBertallanffy模型拟合效果较佳,拟合度为0.9800,南阳母牛体重的适宜曲线方程为Y=383.97×(1-0.5484×e-0.1128t)3;南阳母牛的生长拐点月龄为4.41月,拐点体重为113.77kg,成熟体重为383.97kg,与其它牛品种生长发育特征比较,南阳母牛较早熟,成熟体重偏小。  相似文献   

7.
植物样品中金的分析方法很多。通过大量试验表明,植物样品的灰化温度和分解方式对金的分析结果影响很大。为此,在大量试验的基础上确立了植物样品在650℃灰化,王水溶解,泡沫塑料分离富集,硫脲解脱金,石墨炉原子吸收测定植物样品中金的分析方法。该方法快速、简单、准确、可靠,方法的检出限为0.29×10~(-9)。用3个含量分别为115.4×10~(-9).15.0×10~(-9),18.1×10~(-9)的植物样品做精密度试验。其相对标准偏差分別是5.26%、21.5%、7.37%。  相似文献   

8.
利用双道原子荧光分析仪对湛江港附近海域表层沉积物砷、汞、铅、镉的含量进行了分析,阐明了这几种重金属的分布特征。结果表明,As的质量分数为(8.138~16.749)×10-6,平均12.745×10-6;Hg的质量分数为未检出(nd)~0.322×10-6,平均0.059×10-6;Pb的质量分数为(14.306~68.904)×10-6,平均44.258×10-6;Cd的质量分数为(1.561~6.882)×10-6,平均3.0874×10-6;砷、汞、铅从港内往港外有逐渐减少的趋势,镉的分布没有规律性,在整个港湾内的分布较均匀。从单因子污染指数看,砷、汞和铅都属生态危害轻微;镉污染较为严重,属生态危害强;从综合污染指数看,属生态危害中等。  相似文献   

9.
提出一种基于分段的重叠窗口拟合算法,它将分段窗口分为边界区、重叠区和内部区,通过对前后窗口重叠区拟合值的加权平均,使窗口间拟合值的变化连续。采用实测GNSS电离层数据,分别对逐历元滑动窗口、独立分段窗口和重叠窗口3种算法进行实验对比,其中在以400历元窗口对NKLG站G01的电离层拟合计算中,逐历元法耗费121.618 s,而独立分段法和重叠分段法只分别用了0.396 s和0.985 s,计算效率分别为前者的307倍和123倍。结果证明,该算法兼顾计算精度与执行效率,是处理数据量较大、连续且变化剧烈的时间序列的有效方法。  相似文献   

10.
研究了痕量Bi催化鲁米诺-邻菲啰啉-H_2O_2-Triton x-305体系产生化学发光及非离子表面活性剂敏化化学发光最佳反应条件,拟定了新的化学发光测定Bi的方法。方法最低检出限达3.7×10~(-10)g/ml,测定响应浓度范围为5×10~(-9)~10~(-5)g/ml,回收率为98.7%~103%,相对标准偏差为2.8%~3.5%之间。  相似文献   

11.
12.
Based on the hydrographic data in austral summer during the 22nd Antarctic Expedition of China(2005/2006),some features can be found about the northern margin of Emery ice shelf as follows.The heat content in the surface layer(0-50 m) at the eastern end and the western end of the ice-shelf margin is much higher than that at the middle.The upper mixing-layer depth and the seasonal thermocline depth at the middle of the ice-shelf northern margin are much shallower than those at the both ends.However there is much less difference between the middle and the ends in the bottom layer.The remote sensing photos show that the inhomogeneity in the surface-layer water is closely related to the spatial distribution of the floes and polynia in the area.  相似文献   

13.
Phylogenetic analysis based on 16S rDNA of 8 strains of cultivable bacteria isolated from Arctic sea-ice was studied.The results showed that strain BJ1 belonged to genus Planococcus,which was a genus of low mole percent G C gram-positive bacteria;strain BJ6 belonged to genus Burkholderia of β-proteobacteria and the rest 6 strain all belonged to γ-proteobacteria,of which strain BJ8 was a species of Pseudoalteromonas,strain BJ2-BJ5 and BJ7 were members of genus Psychrobacter.Phylogenetic analysis also indicated that bacteria of genus Psychrobacter of the isolates formed a relatively independent phylogenetic cluster in comparison with other bacteria belonged to genus Psychrobacter.  相似文献   

14.
正1 Aims and Scope Advances in Polar Science(APS)is an international,peer-reviewed journal jointly sponsored by the Polar Research Institute of China and the Chinese Arctic and Antarctic Administration.APS is a comprchensive academic journal dedicated to presentation of multi-disciplinary achievements in Arctic and Antarctic expeditions and research.Its primary purpose is to publish achievements in fundamental research,applied  相似文献   

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16.
《山地科学学报》2014,(4):I0004-I0009
<正>AIMS AND SCOPE(Editorial Policy)The Journal of Mountain Science(JMS)is devoted to mountains and their surrounding lowlands-ecoregions of particular global importance,with a particular emphasis on the important highlands/mountains in the world,such as the Tibetan Plateau,the Himalayas,the Alps,the Andes,the Rockies and many other mountain ranges of our planet.  相似文献   

17.
<正>The Journal of Mountain Science(JMS),founded in2004,is an international English-language journal on mountain sciences.JMS is supervised by the Chinese Academy of Sciences(CAS),sponsored by the Chengdu Institute of Mountain Hazards and Environment,CAS,published by Science Press China,and distributed by Springer exclusively throughout the world(excluding Mainland China).The JMS is published bimonthly,fulltexted in SpringerLink and CNKI,indexed/abstracted by  相似文献   

18.
Using the NCEP/NCAR reanalysis monthly 500 hPa height data on a 2.5 latitude-longitude grid and 1°×1° sea ice data,the polar vortex area,intensity index and arctic sea ice area index are calculated respectively,and the meridional distribution,period variation and the abrupts in the long range trend are analyzed to study their relationship.The results show that the meridional distribution of sea ice and polar vortex h-ave distinctive difference,the relative positions of them are different in the eastern and western hemispheres,and exept they have periods of 4 months,quasi half year,quasi year,4-5 years and 10 years commonly,and each of them has its own respective variation as well.The sea ice area is decreasing apparently since 1980's,so is the polar vortex area,but their abrupt changge time are different totally.The area of sea ice and polar vortex has prominent positive correlation,but the relationship of sea ice intensity,polar vortex intensity,polar vortex area is complicated.  相似文献   

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20.
<正>The Journal of Ocean University of China(Oceanic and Coastal Sea Research)is a comprehensive academic quarterly sponsored by the Ocean University of China,published one volume per year.This journal is devoted to the publication of the theoretical and applied research  相似文献   

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