Infrared absorption spectra in the range of 250‐4000 cm−1 of the three isomeric methoxyphenols are reported. The para methoxyphenol is in the solid phase at room temperature and its spectrum has been investigated in the range of 700‐4000 cm−1 in chloroform solution in addition to the spectrum recorded for its nujol mull. Under the usual approximation of the two substituent groups taken as point masses the observed bands have been assigned to different modes of vibration. These assignments have been used to calculate the molar thermodynamic functions for these compounds.

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Variable-temperature (−55 to −100 °C) studies of the infrared spectra (3500−400 cm-1) of methylhydrazine, CH3NHNH2, dissolved in liquid xenon have been recorded. From these data the enthalpy difference has been determined to be 323 ± 30 cm-1 (3.86 ± 0.36 kJ/mol) with the inner conformer (methyl group staggered and between the two hydrogens of the NH2 group) the more stable rotamer. A complete vibrational assignment is presented for the inner conformer, and several of the fundamentals of the outer conformer have been assigned. These assignments are consistent with the predicted wavenumbers obtained from ab initio MP2/6-31G(d) calculations utilizing three scaling factors. The optimized geometries, conformational stabilities, harmonic force fields, infrared intensities, Raman activities, and depolarization ratios have been obtained from RHF/6-31G(d) and/or MP2/6-31G(d) ab initio calculations. Hybrid density functional theory (DFT) calculations to obtain the structural parameters and conformational stability by the B3LYP method were also carried out. These quantities are compared to the corresponding experimental quantities when appropriate. Additionally conformational stabilities and structural parameters have also been predicted from MP2 level calculations with full electron correlation with 6-311+G(d,p) and 6-311+G(2d,2p) basis sets. The r 0 structural parameters have been obtained from a combination of the previously reported microwave rotational constants and ab initio MP2/6-311+G(d,p) predicted parameters. The results are compared to some corresponding quantities for some similar molecules.

In this paper, an analytical expression is derived for the factor of safety of the rock slope incorporating most of the practically occurring destabilizing forces as well as the external stabilizing force through an anchoring system. The slope stability is analyzed as a two-dimensional problem, considering a slice of unit thickness through the slope and assuming negligible resistance to sliding at the lateral boundaries of the sliding block. A detailed parametric study is presented to investigate the effect of surcharge on the stability of the rock slope for practical ranges of governing parameters such as inclination of the slope face, inclination of the failure plane, depth of tension crack, depth of water in tension crack, shear strength parameters of the material at the failure plane, unit weight of rock, stabilizing force and its inclination, and seismic load. For the range of parameters considered in the present study, it is found that the factor of safety of the rock slope decreases with increase in surcharge; the rate of decrease being relatively higher for lower values of surcharge. It is also observed that for a specific surcharge, the factor of safety depends significantly on all other parameters, except for unit weight of rock and higher values of inclination of stabilizing force to the normal at the failure plane. For any combination of these variables, the surcharge plays a vital role in the stability. A perfectly stable slope at relatively low surcharge can become unsafe with the increase in surcharge. The deterioration in the stability can be quite rapid, depending on the combination of the factors under consideration. The analysis and the general expression proposed herein can be used to carry out a quantitative assessment of the stability of the rock slopes.