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11.
Cif2000平台下的核磁共振测井解谱方法研究   总被引:3,自引:0,他引:3  
王才志  李宁 《测井技术》2002,26(5):360-363
介绍了在Cif2000多井解释平台下的核磁共振解谱方法与编程实现。解谱采用加入平滑因子后在特征矩阵的奇异值分解中截去小的非零奇异值的方法,可以在低信噪比时得到稳定的弛豫谱,在油田实际应用中证明了该方法的有效性。根据该方法在Cif2000平台上编制了完整的解谱处理程序,可以直接用于油田的生产实际。  相似文献   
12.
The electron‐spin‐resonance (ESR) spin‐probe method, was used to study the heterogeneity of denture resins based on poly(methyl methacrylate). Results for three resins processed by microwave energy, conventional curing and cold curing (depending on the curing procedure and exposed to ageing in various environmental conditions) were compared. All three cured resins were stored over the same time (1200 h) in distilled water at ambient temperature and in artificial saliva at 348 K. The temperature‐dependent ESR spectra of a spin probe dispersed in the denture resins are analyzed in terms of line‐shapes and line‐widths. The appearance of two spectral components was taken as an indication of resin heterogeneity. The results reveal that the cold‐cured resin has a lower local density in comparison with microwave and conventionally cured resin. The amount of residual monomer also contributes to the local motion of polymer segments. The change of denture resins exposed to ageing is influenced both by the structure of the original resin and the ageing conditions. Restricted motion of a spin probe incorporated into the acrylic resins exposed to accelerated ageing suggests additional crosslinking of polymer chains. The differences are observed for all the investigated resins, but the highest change is observed with the cold‐cured resin. The ESR results are accompanied by Tg and Tm measurements. Copyright © 2005 Society of Chemical Industry  相似文献   
13.
提出一种配电网电容电流测量的新方法,在零序电压互感器的开口三角侧串联一个可调电感,通过注入一个变频恒流信号寻找配电网的谐振频率,改变可调电感的数值后寻找另一谐振频率,联立2个谐振方程求解电容电流,该方法消除了电压互感器漏抗对测量的影响。开发了配电网电容电流测量仪,经模拟试验和现场测试表明,该方法具有安全、快捷、准确等特点,适用于中性点不接地或经随调式消弧线圈接地配电网。  相似文献   
14.
针对铁路提速后出现的上承式简支钢板梁桥跨中横向振幅过大的问题,以羊楼司桥(L=32m单跨上承式简支钢板梁桥)为例进行实桥检测和数值模拟,建立车辆、线路、桥梁三者的联合模型,考虑轮轨接触力,应用MSC/DYTRAN大型结构分析程序进行车线桥动力相互作用的仿真分析。研究揭示我国用量最多的C62型货车以70∽80km/h的速度空载通过时,该跨度的钢板梁桥发生横向谐振的机理。此外,用该方法对32m跨长的组合梁结构进行桥梁动力特性及列车走行性分析,表明该结构满足提速货车和高速电动旅客列车走行的要求。研究结果对我国高速铁路桥梁建设和既有桥梁的改造具有积极意义。  相似文献   
15.
衰减系数的校正是磁共振波谱信号处理和分析过程中的一个关键难题。本文基于复数主成分分析,提出了一种自动的磁共振波谱衰减系数的校正方法,较成功地解决了这个难点问题。文中的模拟数据及其实现结果充分验证了该方法的有效性。  相似文献   
16.
High cycle fatigue of bolted connections Extensive tests regarding the influences on the fatigue of bolt‐nut‐connections of preloading with torsion, of preloading with yielding, of loading with superimposed bending and of the tested lot are processed. These influences are not yet known according to VDI 2230. New testing devices were designed for these tests, which allow a far less expensive operation and may easily be used for bolts of diameters up to M100 and testing frequencies up to 1000 Hz. The validity of fatigue resistance according to VDI 2230 is specified with respect to the test results. The determined influence of the tested lots is unexpectedly high. The manufacturing process of bolts should be improved to minimize this influence.  相似文献   
17.
提出一种金属圆锥弹簧与橡胶圆锥弹簧复合而成的弹簧.分析表明:它可以应用于弹性耦合激励振动筛和座式直线振动筛。  相似文献   
18.
综述了电子自旋共振在橡胶的合成、加工和应用领域的应用现状及其发展前景。  相似文献   
19.
The proton nuclear magnetic resonance spectroscopy (1H-NMR), the synchronous fluorescence spectrometry (SFS) and the ruthenium ions catalyzed oxidation (RICO) method were used to determine the chemical structure of polyaromatic nucleus in Oman residue fractions. The results of 1H-NMR analyses showed that the average numbers of aromatic rings in the aromatics, resins and asphaltenes units were 3.2, 5.6 and 8.2, respectively. SFS was used to investigate the distribution of aromatic rings in residue fractions, the main distribution range of aromatic rings in aromatics, resins and asphaltenes were 3 4 rings, 3--5 rings and more than 5 rings, respectively. The aromatic network in residue fractions was oxidized to produce numerous carboxylic acids. The types and content of benzenepolycarboxylic acids, such as phthalic acid, benzenetricarboxylic acids, benzenetetracarboxylic acids, benzenepentacarboxylic acid and benzenehexacarboxylic acid disclosed the condensed types of aromatic nuclei in the core. The biphenyl fraction (BIPH), the cata-condensed fraction (CATA), the peri-condensed fraction (PERI) and the condensed index (BCI) were calculated based on the benzenepolycarboxylic acids formed. The results implied that there was less biphenyl type structures in all residue fractions. The aromatics fraction was almost composed of the cata-condensed type system, and the asphaltenes fraction was wholly composed of the peri-condensed type system, while in the resins fraction co-existed the two types, herein the peri-con- densed type was predominant over the cata-condensed type. Based on the analytical results obtained in the study, the components --aromatics, resins and asphaltenes -- were given the likely structural models.  相似文献   
20.
Hot carrier magnetophonon resonances of n-type Si, short channel InP and p-type InSb were investigated in pulsed high magnetic fields up to 40 T. Using a recently developed high resolution technique in pulsed high fields, many new features of the hot carrier-phonon interactions in high magnetic fields were found.  相似文献   
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