We present detailed parameter determinations of two chemically normal late A‐type stars, HD 32115 and HD 37594, to uncover the reasons behind large discrepancies between two previous analyses of these stars performed with a semi‐automatic procedure and a ‘classical’ analysis. Our study is based on high‐resolution, high signal‐to‐noise ratio spectra obtained at the McDonald Observatory. Our method is based on the simultaneous use of all available observables: multicolour photometry, pressure‐sensitive magnesium lines, metallic lines and Balmer line profiles. Our final set of fundamental parameters fits, within the error bars, all available observables. It differs from the published results obtained with a semi‐automatic procedure. A direct comparison between our new observational material and the spectra previously used by other authors shows that the quality of the data is not the origin of the discrepancies. As the two stars require a substantial macroturbulence velocity to fit the line profiles, we concluded that neglecting this additional broadening in the semi‐automatic analysis is one origin of discrepancy. The use of the Fe i excitation equilibrium and the Fe ionization equilibrium to derive effective temperature and surface gravity, respectively, neglecting all other indicators leads to a systematically erroneously high Teff. We deduce that the results obtained using only one parameter indicator might be biased and that those results need to be cautiously taken when performing further detailed analyses, such as modelling of the asteroseismic frequencies or characterizing transiting exoplanets.

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The variations in the ambient concentrations of particulate matter (SPM and PM 10) and gaseous pollutants (SO 2 and NO 2) at Clock tower (CT), Rajpur road (RR) and Inter State Bus Terminal (ISBT) station in Dehradun city, Uttarakhand, India are analysed for the period of 2011-2014. Mean concentrations are observed to be higher during pre-monsoon season as compared to the winter and monsoon. PM 10 and SPM concentrations with maximum values of 203 ± 23 and 429 ± 49 µg m −3 , respectively, during winter, are found to exceed the national standards by factors of 2 and 3. Winter-time elevated pollution in Dehradun is attributed to the lower ventilation coefficient (derived from Era interim model fields) and minimal precipitation. Nevertheless, the SO 2 and NO 2 levels are observed to be within the criteria notified by the Central Pollution Control Board (CPCB), India. Correlation analysis shows profound impacts of the meteorology and local dynamics on the observed variations in observed trace species. Additionally, the stronger inter-species correlation variations (r = 0.79 for SO 2 with NO 2 , and r = 0.89 for PM 10 with SPM), which may suggest their origin from common sources. Analysis of 'Air Quality Index (AQI)' variations indicates unhealthy atmospheric conditions near the major city centers and bus station. More observations in the region are highly desirable to understand the dispersion of the enhanced pollution in the Dehradun valley.

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We present here a new technique, called vapour phase spray pyrolysis, for deposition of TO and ITo films. Undoped TO film showed semiconducting nature, a sheet resistance of 1088tiff-I, a donor ionization energy level of 40meV, average visible transmittance of 75-4 ~o and n-type conductivity. The indium doped (ITO) film 10 wt ~o showed metallic nature, a sheet resistance of 15 f~/O, average visible transmittance of 804 To and ptype conductivity. Thus the TO and 13"o films showed fitirly good electro-optical qualities, comparable to those obtained by sophisticated and costly techniques.