注胶晕长石的鉴定方法     

李建军  刘晓伟  李桂华 《地质科学译丛》2011,(4):43-46

近期,国家黄金钻石制品质量监督检验中心对一串具蓝色晕彩的长石手链样品进行常规检测时,在长波紫外灯下多数珠子发中等强度的蓝白色荧光,且荧光在珠子中呈线状分布。为了对该长石样品进行准确定名,并探究其紫外荧光产生的原因,对其进行了常规宝石学检测、电子探针和红外光谱测试与分析。结果显示,该样品的折射率约为1.53,在显微镜下具有层状结构和针片状包裹体,结合其电子探针的分析结果,确定该样品为晕长石,即具有蓝色晕彩的钠长石;基于样品表面具有典型的＂蚯蚓行踪＂纹路、沿裂隙发出的紫外荧光及红外光谱下3 053,3 038cm^-1处的吸收峰,确定其为注胶处理的晕长石。  相似文献   

爆心距对爆破震动信号频谱的影响分析     

毕卫国  田岗  燕永峰 《岩土工程技术》2011,25(6):304-306

结合临沂某一隧洞工程,利用matlab分析软件分析了不同爆心距下的爆破震动信号的频谱变化情况。得出：在爆破中近区,震动信号的主频在垂直方向的分量较水平方向大,随着爆心距的增加地面震动峰值速度的主震方向会由水平方向向垂直方向转化,总体呈衰减趋势,震动主频趋向于低频;在爆破参数和爆区特征类似于本工程的工程爆破现场其中低频震动信号在水平方向上的分量所占能量比例高于垂直分量的能量比例,在距爆源较远的位置也不能忽略爆破震动对建筑结构的影响,尤其是要加强水平方向的抗震设防。  相似文献   

核磁共振T2谱M-P广义逆反演研究     

李鹏举  姜大鹏  李鹏飞  宋延杰 《吉林大学学报(地球科学版)》2011,41(2):579-585

基于广义逆和奇异值分解理论,研究核磁共振T2谱反演的截断法和阻尼法。首先给出反演问题的M-P广义逆解;然后对系数矩阵进行奇异值分解求其M-P广义逆,对奇异值进行截断或者加阻尼,保证解的稳定性兼顾其分辨率;最后利用迭代技术实现解的非负约束。数值仿真实验和岩心T2谱反演表明:对于双峰谱,在信噪比SNR≥10时,截断法和阻尼法反演T2谱的分辨率和稳定性都很高;截断法截断因子选择范围小,在SNR<10时解的分辨率和稳定性差;阻尼法阻尼因子选择范围大,在SNR<10时解的稳定性好,但短组分分辨率低,长组分分辨率高。对于三峰谱,当SNR≥20时,截断法和阻尼法反演的T2谱光滑连续,具有三峰结构;当SNR<20时两者均不能反演出与构造谱接近的三峰谱。因此,2种方法可应用于SNR≥10的双峰谱和SNR≥20的三峰谱反演;从分辨率和稳定性、平滑噪声及截断和阻尼因子的选取上,阻尼法略优于截断法。  相似文献   

煤田采区高分辨三维地震勘探激发参数的优选     

蔺国华  倪新辉  杨文强 《中国煤炭地质》2011,(10):62-65

三维地震勘探取得可靠数据的前提是获得最佳的的激发参数,即激发井深和激发药量。双井微测井是一种行之有效的确定激发参数的方法。以某区25m双井微测井为例,介绍了通过不同激发井深的接收排列图及频谱分析图确定潜水面位置及最佳激发深度的方法;在确定的最佳激发层位上进行不同药量试验,结合目的层有效波时窗频谱图,综合考虑有效信号、地震子波频谱及信噪比等因素选择最佳激发药量。通过双井微测井工作,最终确定潜水面位置为6m,最佳激发深度为11m,激发药量为2kg。  相似文献   

后赤潮过程中现场水样的三维荧光光谱特征分析     

吴永森  吴绍渊  李赟  李瑞香  殷月芬 《海洋与湖沼》2011,42(6):892-898

对发生在青岛近岸水域的后赤潮过程中赤潮藻密度、藻种进行鉴别的同时,对现场水样的三维荧光光谱进行了测量,获得了一套三维特征荧光数据。分析结果表明,1）当海水中生物密度达到或接近赤潮密度时,Ex最高峰值波长位于245nm,Em最高峰值波长在445nm,激发转折波长在260nm,荧光转折波长在245nm;2）在非赤潮区,Ex...  相似文献   

Propagation of water waves over permeable rippled beds     

Ching-Jer Huang  Chih-Hsin Chen 《Ocean Engineering》2011,38(4):579-591

Unsteady two-dimensional Navier-Stokes equations and Navier-Stokes type model equations for porous flow were solved numerically to simulate the propagation of water waves over a permeable rippled bed. A boundary-fitted coordinate system was adopted to make the computational meshes consistent with the rippled bed. The accuracy of the numerical scheme was confirmed by comparing the numerical results concerning the spatial distribution of wave amplitudes over impermeable and permeable rippled beds with the analytical solutions. For periodic incident waves, the flow field over the wavy wall is discussed in terms of the steady Eulerian streaming velocity. The trajectories of the fluid particles that are initially located close to the ripples were also determined. One of the main results herein is that under the action of periodic water waves, fluid particles on an impermeable rippled bed initially moved back and forth around the ripple crest, with increasing vertical distance from the rippled wall. After one or two wave periods, they are then lifted towards the next ripple crest. All of the marked particles on a permeable rippled bed were shifted onshore with a much larger displacement than those on an impermeable bed. Finally, the flow fields and the particle motions close to impermeable and permeable beds induced by a solitary wave are elucidated.  相似文献   

Analysis of characteristics of time-frequency correlations between runoff, tidal range and salinity in the Changjiang Estuary   总被引：2，自引：0，他引：2  

FEI Yuejun  XU Lili  DU Panjun  GUAN Qinle  KANG Xing  XIAO Wenjun 《海洋学报(英文版)》2011,30(5):84-93

Power spectrum and cross-wavelet transform analysis was adopted to study the time-frequency characteristics and multiscale correlations between runoff, tidal range and salinity in the Changjiang Estuary based on the runoff data collected at the Datong Station, the tidal range measured at the Baozhen Station, and the salinity at the Baogang Station from 2008 to 2009. The variations of the salinity showed significant periodicity at scales of 2-3, 7-8, 14-15 and 26-30 d. The correlation between the salinity and the runoff and the tidal range were found to be significantly related to shock at scales of 5-7, 14-15, 26-30 d and 0.5 a. The correlation between the runoff and the salinity was mainly in the same phase, while the correlation between the tidal range and the salinity was in the antiphase. Different frequency bands were related to different degrees, and their relevance increased as the resonance frequency decreased. In addition, changes of the seasonal runoff were obvious. Specifically, a point of discontinuity was reached in early June with a cycle of 7-8 d, which coincided with the periodicity of plum rains in the Changjiang-Huaihe region. High-frequency changes (8-16 d period) of the salinity corresponded to the time domain in January-April 2008, February-April 2009 and October-December 2009 and exhibited an approximately 0.5 a (184 d) long frequency oscillation. Short-period changes were found to be stronger than long-period changes. Cross-wavelet transforms for the salinity, the runoff and the tidal range revealed local features in the time domain, while the significant levels of different periodic oscillations were observed in the frequency domain. The correlation characteristics of the salinity and the runoff were significant in the 80-90 d frequency domain, indicating that the major impact of the runoff on the salinity was reflected in seasonal changes. The tidal range on the small scale of 14-15 and 30-32 d was more obvious than the runoff.  相似文献   

自由站立式立管总体运动疲劳分析     

康庄  李辉  孙丽萍  冯玮  贾旭 《海洋工程》2011,29(4):43-50

由于良好的疲劳特性,自由站立式立管(FSHR)正广泛应用于深海油气田的开发当中。首先根据设计参数建立FSHR详细的有限元模型,然后利用谱分析方法对FSHR进行总体运动疲劳分析,以确定FSHR总体设计参数是否满足运动疲劳要求。最后对工作于相同环境下的钢悬链立管(SCR)进行总体运动疲劳分析,探讨哪种立管系统的疲劳性能更为优良。计算结果表明FSHR系统中刚性主管最大运动疲劳损伤出现在刚性主管顶部,FSHR总体设计参数满足规范要求;FSHR总体运动疲劳寿命要远大于SCR,体现了FSHR系统对浮体运动与刚性主管之间具有良好的解耦作用。  相似文献   

越南巴达棱湾沿岸海域周年风和浪的观测分析     

刘愉强  杨阳  廖世智  冯砚青  赖新云 《热带海洋学报》2011,(5)

基于国内首次在越南巴达棱湾2007年5月—2008年4月的风、浪现场实测资料,对该海区的风和浪的基本特征进行了初步统计分析,得出如下结论:1)海区季风现象明显,冬季(夏季)盛行东北(西南)季风,东北季风强度大于西南季风强度;2)海区波向与风向基本一致,即冬季(夏季)常浪向和强浪向均是E(SSW)向浪;3)海区以风浪为主,波谱表现为多峰结构,主峰多为单峰和双峰结构,东北季风(西南季风)期间,峰值周期对应的波向为E(SSW)向,台风对海域的波谱影响明显。文章结果对认识与我国同纬度的南沙群岛海域的风、浪特点具有一定参考价值。  相似文献   

不同取代位置羧甲基壳聚糖的核磁共振波谱和电位滴定分析     

王远红  王聪  于明明  张秀丽  姜廷福  刘潇潇  孟适秋  吕志华 《中国海洋大学学报(自然科学版)》2011,(Z1):359-364

本文制备了O-羧甲基壳聚糖、N-羧甲基壳聚糖和N,O-羧甲基壳聚糖,并采用核磁共振波谱以及电位滴定方法对不同取代位置羧甲基壳聚糖取代度进行了分析。结果表明,核磁共振碳谱及DEPT谱可以确定羧甲基壳聚糖中羧甲基的取代位置,电位滴定法可以确定O-位羧甲基、N-位羧甲基以及总羧甲基的取代度,是一种简单易行的方法。  相似文献