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41.
The Mt. Suhora M dwarf survey searching for pulsations in low mass main sequence stars has acquired CCD photometry of 46 M dwarf stars during the first year of the project (Baran et al., 2011). As a by-product of this search hundreds field stars have been checked for variability. This paper presents our initial result of a search for periodic variables in field stars observed in the course of the survey. On the basis of the periodicity and the shape of the light curves, eight new variables has been detected, among which five are δ Scuti stars and three likely RR Lyrae stars. Although variation in one of the stars has been previously detected, it was classified incorrectly. To support our classification, in August 2010, we performed spectroscopic observations to derive spectral types and luminosity classes for all eight variable stars.  相似文献   
42.
Since Baade's photographic study of M32 in the mid 1940s, it has been accepted as an established fact that M32 is a compact dwarf satellite of M31. The purpose of this paper is to report on the findings of our investigation into the nature of the existing evidence. We find that the case for M32 being a satellite of M31 rests upon Hubble Space Telescope (HST) based stellar population studies which have resolved red-giant branch (RGB) and red clump stars in M32 as well as other nearby galaxies. Taken in isolation, this recent evidence could be considered to be conclusive in favour of the existing view. However, the conventional scenario does not explain M32's anomalously high central velocity dispersion for a dwarf galaxy (several times that of either NGC 147, NGC 185 or NGC 205) or existing planetary nebula observations (which suggest that M32 is more than twice as distant as M31) and also requires an elaborate physical explanation for M32's inferred compactness. Conversely, we find that the case for M32 being a normal galaxy, of the order of three times as distant as M31, is supported by: (1) a central velocity dispersion typical of intermediate galaxies, (2) the published planetary nebula observations, and (3) known scaling relationships for normal early-type galaxies. However, this novel scenario cannot account for the high apparent luminosities of the RGB stars resolved in the M32 direction by HST observations. We are therefore left with two apparently irreconcilable scenarios, only one of which can be correct, but both of which suffer from potentially fatal evidence to the contrary. This suggests that current understanding of some relevant fields is still very far from adequate.  相似文献   
43.
李阳 《地质学报》2009,83(3):426-434
从断层岩入手,分析了断层岩与断层封闭性的相关性,进一步建立起断层岩纵向类型变化与断层封闭性的关系。根据断层岩的类型及含油气沉积盆地的埋深,把泥岩涂抹类型分为未成岩塑性剪切型泥岩涂抹及成岩脆性研磨型泥岩涂抹。根据岩石纵向流变性,把断层封闭性分为浅层高渗封闭开启段、中层碎裂封闭开启段及下层韧性变形封闭段,并加以对比与剖析。探讨了泥岩涂抹定量表征问题,指出不同泥岩涂抹类型应采取的计算方法及目前研究中存在的问题。对东辛油田营32断层的泥岩涂抹研究表明,该断层南段几个重要含油层位的封闭性不好,导致油气穿越断层,发生了油气再运移,而北段所有含油层位都是封闭的。这说明了同一条断层封闭的差异性及动态性。  相似文献   
44.
作者在对Win16和Win32进行比较的基础上,结合作者在移植过程中的实际经验,对遇到的一些问题和解决办法以及移植步骤作了详细的探讨和总结。  相似文献   
45.
^32Si是宇宙成因的放射性同位素,其半衰期约为200a,应用^32Si作为示踪剂测定地下水年龄的范围为50-1000a。本文介绍了应用F e(OH)3共沉法从天然水中提取SiO2的制备方法。  相似文献   
46.
放射性同位素^32Si及其研究进展   总被引:1,自引:0,他引:1  
放射性同位素^32Si的半衰期介于常用的环境同位素^3H和^14C之间,能测定50 ̄1000a之间水的年龄,是一个其它同位素所不能替代的测年工具,本文介绍了^32Si的起源、在水圈各部分的分布规律,影响因素、测试方法及其在海洋学、冰川学和水文地质学方面的应用研究。  相似文献   
47.
黄铁矿表面的扫描隧道显微镜研究   总被引:3,自引:0,他引:3  
为了探讨硫元素在煤中的赋存,对煤硫元素的主要载体黄铁矿的表面进行了扫描隧道显微镜研究,在硅油保护下得到了黄铁矿表面高分辨率图象。根据黄铁矿晶体结构的几何分析,所观察到的是黄铁矿{220}表面的原子分布,黄铁矿的能带结构资料及前人在这方面的研究均表明,用扫描隧道显微镜应首先观察到黄铁矿表面的铁原子,但作者首先观察到的却是黄铁矿表面的硫原子,此外,作者根据所获得的实验结果认为。无论是在{210}文向还  相似文献   
48.
Based on the established mathematic model and graphic interpretation, a new method, which is used to calculate the contribution of single-zone production in a commingled producing well by the ultraviolet spectrum technique, has been established. The standard plate was drawn using the extinction coefficient E of sample oils formulated artificially as y-axis and the wavelength as x-axis. The curve resulting from the UV analysis of sample oils in the commingled well was inserted into the standard plate and compared. The proportion of each single zone in the commingled producing well was identical with the proportion of the curve which is closest to the curve of sample oils formulated artificially. In the well QHD32-6-3 field, taking well A22 for example and using this method, the production contribution of a single zone was calculated. The result showed that the Nm4 zone is a major "contributor", the proportion of the Nm4 zone is 70%, and that of the Nm1 zone is 30%. The ultraviolet spectrum technique provided a new reservoir geochemical technique of monitoring production contribution, especially for biodegraded heavy oil, but it has some limitation, just depending on the GC fingerprint technique.  相似文献   
49.
We present 53 simultaneous photometric ( I band) and spectroscopic (69009500 Å) observations of GRO J0422+32, taken during 1997 December. From these we determine that J0422+32 was in its lowest state yet observed, at I =20.44±0.08. Using relative spectrophotometry, we show that it is possible to correct very accurately for telluric absorption. Following this, we use the TiO bands at 7055 and 7589 Å for a radial velocity study and thereby obtain a semi-amplitude of 378±16 km s1, which yields f ( M )=1.191±0.021 M and consistent with previous observations. We further demonstrate that this little-explored method is very powerful for such systems. We also determine a new orbital ephemeris of HJD=245 0274.4156±0.0009+0.212 1600±0.000 0002 E .
We see some evidence for an ellipsoidal modulation, from which we determine the orbital inclination of J0422+32 to be less than 45°. We therefore calculate a minimum mass for the primary of 2.22 M, consistent with a black hole, but not necessarily the supermassive one proposed recently (1997) by Beekman et al. We obtain an M45 spectral type for the secondary star, and determine that the secondary contributes 38±2 per cent of the flux that we observe from J0422+32 over the range 69508400 Å. From this we calculate the distance to the system to be 1.39±0.15 kpc.  相似文献   
50.
Dating the recent past   总被引:2,自引:1,他引:1  
The dramatic environmental changes of the last 500 years are likely to continue into the future and to have an increasing impact on both the Earth and human society. Any understanding of future environmental change is thus critically dependent on our capacity to reconstruct the environmental changes of the past. Fundamental to this is an ability to place the environmental responses of the last half millennium within a reliable chronological framework. Unfortunately, this most recent part of the geological timescale presents us with some of the greatest challenges for dating. With the exception of 230Th/234U methods, whose use is restricted to the rather specific depositional environments of shallow marine and terrestrial carbonates, there is no established geochronometric tool capable of dating more than a fraction of the recent past at a resolution adequate to tackle the environmental issues of this period. This challenge has been met by refining existing procedures (including 14C, 40Ar/39Ar, event chronostratigraphy and optically stimulated luminescence) and developing new ones (such as 32Si). These offer a means of calibrating the high-resolution environmental records of the last 500 years and answering the critical environmental questions presented by this period.  相似文献   
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