Supported niobium pentoxide materials have been effective catalysts for a variety of acid and redox reactions (e.g., dehydration of alcohols, esterifications, etc.). To the best of our knowledge, there are no reports about Nb 2 O 5 supported on silica-alumina. Catalysts of Nb 2 O 5 /SiO 2 -Al 2 O 3 were prepared with 2, 5, 10, 15, 20, and 25 wt % of Nb 2 O 5 by aqueous solution impregnation using ammonium niobium oxalate on silica-alumina. The materials, after being dried at 100 °C, were calcined at 800 °C and characterized by several methods. Investigation through X-ray diffraction showed the typical patterns of crystalline Nb 2 O 5 , which were composed of mixtures of orthorhombic and monoclinic phases (T, M, and H, respectively) present in the materials with content higher than 10 wt %. DTA curves displayed an exothermic peak at 1356 °C (average) without mass loss (confirmed by TG), which may be ascribed to a phase transition (H phase formation) of Nb 2 O 5 supported on silica-alumina. Pure Nb 2 O 5 ‚nH 2 O showed a transition from amorphous to hexagonal or orthorhombic phase (TT or T, respectively) at 567 °C. FTIR and DRIFTS results confirmed the reaction of the niobium oxide with the hydroxyl functionality of silica-alumina. The formation of surface niobium pentoxide species over the support through selective and progressive consumption of hydroxyl groups from the support and the appearance of characteristic niobium hydroxylated species on the surface were demonstrated. Raman spectra attested a two-dimensional overlayer of niobium pentoxide on silica-alumina at contents below 10 wt %. At higher concentrations, the absorptions characterize the formation of phases T and H of bulk Nb 2 O 5 .

Biodiesel (FA esters) has become very attractive as an alternative diesel fuel owing to its environmental benefits. Transesterification is the most usual and important method to make biodiesel from vegetable oils. This article investigates the potential for using Raman spectroscopy to monitor and quantify the transesterification of soybean oil to yield ethyl esters. The differences observed in the Raman spectra of soybean oil after transesterification were a peak at 2932 cm −1 (ν CH 2 ), the displacement of the ν C=O band from 1748 to 1739 cm −1 , and the bands at 861 (ν R-C=O and ν C-C ) and 372 cm −1 (δ CO-O-C ). Uni-and multivariate analysis methods were used to build several analytical curves and then applied in known samples, treated as unknowns, to test their ability to predict concentrations. The best results were achieved by Raman/PLS calibration models (where PLS = partial least squares regression) using an internal normalization standard (ν =C-H band). The correlation coefficient (R 2 ) values so obtained were 0.9985 for calibration and 0.9977 for validation. Univariate regression analysis between biodiesel concentration and the increasing intensity of ν CH 2 band or ν C=O displacement showed R 2 values of 0.9983 and 0.9742, respectively. Although spectroscopic methods are less sensitive than chromatographic ones, the data obtained by spectroscopy can be correlated with other techniques, allowing biodiesel yield and quality to be quickly assessed.

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Purpose The purpose of this paper is to analyze the best way to create value in Portugal through quality and innovation and also to check what needs to be improved. Design/methodology/approach A questionnaire was applied to population of 152 companies, with the research and development (R&D) management certified by Portuguese Standard NP 4457. The final sample was 66 companies, which correspond to 45 percent of the population. Statistical analysis of the data collected was performed using IBM SPSS Statistical Software. Findings The authors highlighted the main reasons/motivations that led companies to implement the NP 4457, which were, among others, competitive advantage and creating value. The systematization of information and the generation and management of ideas were highlighted as the main advantages. The lack of methodologies for innovation management and knowledge management was the difficulty experienced in the implementation of NP 4457. Portugal needs to increase patent registration and it also needs to know how to take advantage of the investment made in R&D, in order to decrease the unit cost of knowledge. Portuguese engineering should be more about product design than production processes. The involvement of top management must be greater. Originality/value This investigation contributes to the innovation and quality body of knowledge, since it explores the complementarity between the two concepts as sources of value creation. This case study is one of the first Portuguese empirical research works about value creation through quality and innovation in Portugal. It also allows to know in detail the Portuguese business reality in terms of innovation management.

PurposeThe purpose of this paper is to investigate social capital's effect on family business development in selected family media firms.Design/methodology/approachThe statistical population includes 100 individuals who run a family business in this industry. Eighty individuals are selected as the research sample through the stratified random sampling method. The data are collected using a questionnaire. The authors used structural equation modelling method for data analysis.FindingsThe results indicate that social capital affects the development of family businesses in media firms. According to the results obtained from the structural equation test, the effect of the relational dimension of social capital on trust and the effect of the cognitive and structural dimensions of social capital on trust are supported, while the effect of the relational dimension of social capital on commitment as well as the effect of the cognitive dimension of social capital on trust are not supported.Practical implicationsThis research could help family firms in media industries improve trust and commitment by paying attention to different aspects of social capital. Besides, it shows that even the impact of relational and cognitive social capital, respectively, on commitment and trust, are not supported; these two could affect trust and commitment, respectively.Originality/valueThe paper is among the first studies that investigate family firms in media industries. Besides, the relationships between relational, cognitive and structural aspects of social capital and trust and commitment are rarely studied in the literature as two determinants of family business development.