The Ostwald coefficients L2,1 of He, Ne, Ar, Kr, Xe, N2, O2, CH4 CF4 and SF6 dissolved in several homologousn-alkanes,n-C1H21+2, 6≤l≤16, andn-alkan-1-ols,n-C1H21+1OH, 1≤l≤11, were recently measured at 298.15 K and atmospheric pressure with a modified Ben-Naim/Baer apparatus. Altogether, 201 gas/liquid systems were investigated. For about half of these systems, both pressure control and measurement of the volume of gas dissolved in a given volume of solvent were achieved with a microprocessor. This improved medium-precision instrument (σ≤0.5% in most cases) combines easy handling with fully automated data retrieval, and is totallymercury-free. In this communication, the salient points of data reduction are presented, with the focus on the estimation of several important auxiliary quantities such as second virial coefficients and partial molar volumes at infinite dilution. The effect of the chain lengthl of then-alkane or then-alkan-1-ol upon solubility is demonstrated, and some correlations betweenL2,1, or the derived Henry fugacitiesH2,1, and appropriate molecular and/or bulk properties of the gases and the solvents are discussed.
least squares (OLS), fixed effects panel and first-differences general method of moment (GMM) model tests were executed in EViews on a dataset for 25 EU countries covering 1996–2017. The research question was as follows: Do the various appropriations (i
suffice in identifying statistically significant and positive relationships between centrality of research specialization and time, and it would certainly rule out any sort of multivariate analysis. We opt for OLS and log-transform the dependent variable
Baier , S. L. – Bergstrand , J. H. ( 2009 ): Bonus vetus OLS: A simple method for approximating international trade-cost effects using the gravity equation . Journal of International Economics 77 ( 1 ): 77 – 85
also present fixed effect estimations. The long-term relationships are calculated with the Dynamic OLS (DOLS) method, as this method accounts for the serial correlation and heteroscedasticity of the residual by adding the leads and lags of the
Authors:Giuseppina Castronuovo, V. Elia and Filomena Velleca
Enthalpies of dilution of ternary aqueous solutions containing glucose and alkan-1-ols, alkan-1,2-diols and alkan-m,n-diols were determined at 298.15 K by flow microcalorimetry. The pair-wise cross interaction coefficients of the virial expansion of the excess enthalpies were evaluated: they are positive and depend in a complex manner on the length of the alkyl chain of the alkanols. The behaviour of these systems is interpreted in terms of preferential interactions between the hydrophilic groups of the alkanols and the destructured domain present on glucose.
Authors:James Dietz, Ivan Chompalov, Barry Bozeman, Eliesh Lane and Jongwon Park
In this paper we assess the utility of the curriculum vita (CV) as a data source for examining the career paths of scientists and engineers. CVs were obtained in response to an email message sent to researchers working in the areas of biotechnology and microelectronics. In addition, a number of CVs were obtained "passively" from a search of the Internet. We discuss the methodological issues and problems of this data collection strategy and the results from an exploratory analysis using OLS regression and event history analysis. In sum, despite difficulties with coding and variation in CV formats, this collection strategy seems to us to hold much promise.
Authors:Martin Grančay, Nóra Grančay and Jolita Vveinhardt
In 1961, Staffan Linder attacked mainstream trade economics by diverging from the generally accepted factor endowments theory and focusing on alternative explanations of why countries trade with each other. He was among the first economists to recognise the growing importance of intraindustry trade and presented his hypothesis that the more similar the per capita income levels of countries, the more they tend to trade with each other. This observation has since become one of the main pillars of modern trade theory. The present paper assesses the empirical validity of the Linder hypothesis in the Visegrad countries. Using a variant of the gravity model, it finds that when controlling for other factors, the Visegrad countries tend to trade more with countries with similar per capita income levels than with significantly richer or poorer countries. This observation is consistent with the Linder hypothesis. OLS regressions, Tobit regressions, and robustness checks all support the hypothesis.
Authors:Irena Vovk, Breda Simonovska, Pia Vuorela and Heikki Vuorela
The separation of (+)-catechin and (−)-epicatechin on cellulose TLC plates with 1-butanol-water-acetic acid, 4 + 2 + 1 (
), has been studied under different development conditions on prewashed and untreated TLC plates. Plates were developed in horizontal chambers (tank and sandwich configuration) and in twin trough (unsaturated and saturated) developing chambers. Tank configurations were used with and without preconditioning.Prewashing of the TLC plates, preconditioning, and the type of development chamber used had a large effect on the chromatographic results. Without prewashing of the TLC plate unsatisfactory or misleading results were obtained.Anisaldehyde-sulfuric acid dipping reagent proved to be more selective than vanillin-phosphoric acid as detection reagent for the detection of flavan-3-ols in oak bark extract; the latter was, however, more sensitive.
Authors:Leszek Morawski, Małgorzata Kalbarczyk-Stęclik and Rafał Miśta
Equivalence scales are commonly employed in income analysis to compare the wealth of households of various compositions (e.g., 0-child, 1-child). The choice of weights for this type of analysis is not self-evident. In this paper, subjective equivalence scales for households in Poland, the Czech Republic, and Hungary are estimated. We use longitudinal EU-SILC data for 2005–2012 following the approach of Goedhart et al. (1977) as employed by Bishop et al. (2014). The use of longitudinal data shows that previous results on the subjective minimum income that were based on the OLS estimates for cross-section data overestimated the impact from current income and underestimated the role of economies of scale. Subjective equivalence scales imply a decreasing marginal cost of children in the three countries, which makes them distinct from the OECD scale. The marginal cost of a first child is similar to the values assumed in the OECD scale, but the cost of a second child is much lower.