Rotational mixing

Figure 6. Vacuum mixer for lead paste 1, mixing compartment 2, fast-rotating mixing tools 3, material-deflecting plate 4, discharge opening 5, static, vacuum-sealed enclosure [21J.

Abstract. The chemical composition of B 12, a Be star in the SMC cluster NGC 330, is analysed using high-resolution UVES/VLT spectra and the non-LTE model atmosphere code TLUSTY. A differential analysis relative to a SMC standard star AV 304 revealed (1) a general under-abundance of metals compared with that expected for the SMC, and (2) the lack of nitrogen enhancement. The former is attributed to the presence of a disk, and its contribution to the overall emission is estimated. Possible explanations for the lack of rotational mixing in the apparently rapidly rotating star are discussed. 

Fig. 3. Measured Li abundances in the Hyades. Superposed is the pattern of AM transport required to produce the Li dip in terms of rotational mixing...

Rotational mixing does not affect significantly the stellar structure (Lbump is the same in models A, B and C), but leads to larger abundance variations on the lower RGB associated with a deeper first dredge-up (Fig. lb). 

Rotation remains the best candidate for extra-mixing in RGB stars. The present modelling of the rotational mixing is however still incomplete, and agreement between self-consistent models and observations might be achieved by improving the description of the hydrodynamics related to rotation. 

Rotational Mixing in Massive Stars and Its Many Consequences... 

As a result of the rotational mixing, products of the CNO processing are reaching the stellar surface during MS evolution and produce N/C enhancements, as... 

In solution, the drug may hydrolyze to yield diethylaminoethanol and 4-aminobenzoic acid. For the analysis, the sample solution is treated with 0.2 M (NH4>2Zn(SCN)4, heated to the onset of boiling, and cooled with slow rotational mixing for 4 minutes. This process yields clear solution and an oily precipitate, which is filtered through cotton wool. The filter is washed with 10% NH4SCN solution, and cooled to IT C. The precipitate is dissolved in acetone or dimethylformamide. Water, ammonia buffer solution (pH unspecified), and acid chrome black special indicator are added, and the mixture titrated with 10 mM EDTA to determine Zn(II), and hence procaine. 

Aromatic aldehydes (10 mmol) and trimethylorthoformate (20 mmol) was added to a mixture of sulfonamide (10 mmol), finely powdered calcium carbonate (9 g) and K-10 clay (2 g). The solid homogenized mixture was placed in a modified reaction tube which was connected to a removable cold finger and sample collector to trap the ensuing methanol and methyl formate. The reaction tube is inserted into Maxidigest MX 350 (Prolabo) microwave reactor equipped with a rotational mixing system. After irradiation for a specified period, the contents were cooled to room temperature and mixed thoroughly with ethyl acetate (2 x 20 mL). The solid inorganic material was filtered off and solvent was evaporated to afford tlie residue which was crystallized from the mixture of hexane and ethyl acetate. 

Thalistyline metho salt ( methothalistyline ) (202) was isolated as its diiodide, colorless needles (MeOH), mp 265—267°C (dec.), [a] 1 +125° (c 0.1, MeOH), from the quaternary fractions of roots of Thalictrum longistylum D.C. (78) and T. podocarpum Huns. (34). It was identical by TLC, specific rotation, mixed melting point, and spectral data to material prepared by quatemization of thalistyline (Section II,C, 131) (78). Thalistyline, its metho salt, and N-des-... 

The rotational mixing of the J = 2 and 3 levels by the electronic Zeeman effect, (9.6), may be calculated by second-order perturbation theory, noting that the separation between the two levels is 6/+, where Bq is the rotational constant in the v = 0 level the result is... 

A further refinement in the analysis of the case (a) spectra was described by Carrington and Howard [28] in their study of the CF radical. We have already pointed out that in CIO, for example, it is only possible to determine the total axial magnetic hyperfine constant A 3/2 from studies of the J = 3/2 level alone. In CF, however, the rotational constant Bo is relatively large and the spin-orbit constant A is relatively small. This means that the ratio B0/A is considerably larger for CF (0.0183) than for CIO (0.0022), so that the rotational mixing of the 2n3/2 and 2ni/2 states (equation (9.38)) is more important. This fact, taken with additional measurements of the J = 5/2 level in the 2 n3/2 state, enables both /i3/2 and b to be determined uniquely, though with less accuracy than one would wish. 

Fig. 8. Allowed transitions for the parallel ) and perpendicular (i) vibration-inversion-rotation bands in NH3. System of levels on the right side of the figure illustrates a vibration-rotation mixing of the ground vibrational state with the U4 degenerate state...

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