A Moisture Index Classification System for Rocks (MiC System)

Summary.  Interaction of rocks with water is leading to a reduction in physical and mechanical properties, and quantifying this effect has always been a problem for design purposes in rock engineering projects. Despite the fact that a number of considerable works have been carried out in this field, they are not thorough and general. In this paper, a new rock classification system is presented in order to evaluate wet rock properties. Laboratory studies showed that six parameters may be recognized as major controlling parameters for wet rocks, including: water absorption, porosity, weathering degree, swelling index, number of microfissures, and average grain size. Many tests were performed and a sensitivity analysis was carried out on the data obtained. This analysis characterized the rock sensitivity when changing each parameter and consequently, a rating value was assigned to each parameter. By adding these rating values, a rating between zero and 100 is allocated to each rock as Moisture index (Mi). The closer this index is to 100, the more sensitive rock will be to moisture. On the basis of this index, rocks are divided into five classes including: very good, good, fair, weak and very weak.     

臭氧吸收参数数据库精度检验和验证

利用国际权威期刊上发表的臭氧吸收截面观测数据,检验和验证了现有的紫外正演模式TOMRAD臭氧吸收参数数据库。结果表明,在Hartley臭氧吸收带上,观测数据与数据库参数吻合状况很好;而在Huggins臭氧吸收带上,观测数据与数据库参数在部分波长上存在较大偏差,某些波长上的偏差超过50%。鉴于此,FY-3紫外臭氧探测仪资料处理计算中,选取臭氧吸收参数,必须特别慎重。     

矮新星AB Dra中的吸积盘模型

对矮新星ＡＢ Ｄｒａ的最小二乘拟合表明，黑体吸积盘模型预言的连续谱能粗略地拟合该星在爆发期间的ＩＵＥ观测，较小的偏差可以归因于光学薄气体的复合辐射或／和热斑的黑体辐射，拟合给出了一组吸积盘参量的合理值。     

Jovian auroral spectroscopy with FUSE: analysis of self-absorption and implications for electron precipitation

High-resolution (∼0.22 Å) spectra of the north jovian aurora were obtained in the 905-1180 Å window with the Far Ultraviolet Spectroscopic Explorer (FUSE) on October 28, 2000. The FUSE instrument resolves the rotational structure of the H₂ spectra and the spectral range allows the study of self-absorption. Below 1100 Å, transitions connecting to the v^″?2 levels of the H₂ ground state are partially or totally absorbed by the overlying H₂ molecules. The FUSE spectra provide information on the overlying H₂ column and on the vibrational distribution of H₂. Transitions from high-energy H₂ Rydberg states and treatment of self-absorption are considered in our synthetic spectral generator. We show comparisons between synthetic and observed spectra in the 920-970, 1030-1080, and 1090-1180 Å spectral windows. In a first approach (single-layer model ), the synthetic spectra are generated in a thin emitting layer and the emerging photons are absorbed by a layer located above the source. It is found that the parameters of the single-layer model best fitting the three spectral windows are 850, 800, and 800 K respectively for the H₂ gas temperature and 1.3×¹⁰¹⁸, 1.5×¹⁰²⁰, and 1.3×¹⁰²⁰ cm−2 for the H₂ self-absorbing vertical column respectively. Comparison between the H₂ column and a 1-D atmospheric model indicates that the short-wavelength FUV auroral emission originates from just above the homopause. This is confirmed by the high H₂ rovibrational temperatures, close to those deduced from spectral analyses of H⁺₃ auroral emission. In a second approach, the synthetic spectral generator is coupled with a vertically distributed energy degradation model, where the only input is the energy distribution of incoming electrons (multi-layer model ). The model that best fits globally the three FUSE spectra is a sum of Maxwellian functions, with characteristic energies ranging from 1 to 100 keV, giving rise to an emission peak located at 5 μbar, that is ∼100 km below the methane homopause. This multi-layer model is also applied to a re-analysis of the Hopkins Ultraviolet Telescope (HUT) auroral spectrum and accounts for the H₂ self-absorption as well as the methane absorption. It is found that no additional discrete soft electron precipitation is necessary to fit either the FUSE or the HUT observations.     

火焰原子吸收法测定植物样品中微量铜

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％。     

Radiation pressure acceleration by X-rays in active galactic nuclei

We present calculations of the dynamics of highly ionized gas (HIG) clouds that are confined by external pressure, and are photoionized by AGN continuum. We focus on the gas that is seen, in absorption, in the X-ray spectrum of many AGN and show that such gas can reach hydrostatic equilibrium under various conditions. The principal conclusion is that the clouds can be accelerated to high velocities by the central X-ray source. The dynamical problem can be reduced to the calculation of a single parameter, the average force multiplier, 〈 M 〉. The typical value of 〈 M 〉 is ∼10 suggesting that radiation pressure acceleration by X-rays is efficient for L / L _Edd≳0.1 . The terminal velocity scales with the escape velocity at the base of the flow and can exceed it by a large factor. The typical velocity for a HIG flow that originates at R =10¹⁷ cm in a source with L _x =10⁴⁴ erg s⁻¹ is ∼1000 km s⁻¹, i.e. similar to the velocities observed in several X-ray and UV absorption systems.
Highly ionized AGN clouds are driven mainly by bound–free absorption, and bound–bound processes are less important unless the lines are significantly broadened or the column density is very small. Pressure laws that result in constant or outward decreasing ionization parameters are most effective in accelerating the flow.     

三苯基膦泡沫塑料富集火焰原子吸收分光光度法测定微量银

试样经王水分解,在5％—15％的王水介质中,用三苯基膦泡沫塑料对微量银进行分离富集。用ρ为20g/l的硫脲溶液解脱被吸附在泡沫塑料上的银。解脱液在原子吸收分光光度计上测定银量。方法的检出限为0.022×10~(-■),特征浓度为0.014μg/ml,可测定地质样品中0.0X×10~(-6)以上的银量。