Federal University of São Carlos

About: Federal University of São Carlos is a education organization based out in São Carlos, Brazil. It is known for research contribution in the topics: Population & Microstructure. The organization has 16471 authors who have published 34057 publications receiving 456654 citations. The organization is also known as: UFSCar & Federal University of São Carlos.

Lean manufacturing in Brazilian small and medium enterprises: implementation and effect on performance

Abstract: The main objective of this paper is to investigate the degree to which lean manufacturing (LM) practices are being implemented within Brazilian small and medium enterprises (SMEs), by defining what LM means, in the view of SMEs in Brazil. In addition, the paper investigates the relationship between LM implementation and performance of such companies. The research method used in this paper comprised of an exploratory survey using the partial least-square method with the structural equation modelling technique (PLS-SEM). The results show that the companies studied used practices in a fragmented manner, without a holistic view of LM, which is considered to be one of the most important parts of this approach. Only the constructs of statistical process control, total productive maintenance and employee involvement are being implemented as an integrated approach for Brazilian SMEs. These companies do not take other important constructs such as customer involvement, continuous flow, pull production, set-up time ...

Isothermal and adiabatic nucleation in glass

Abstract: A summary of both classical (isothermal) and adiabatic theories of nucleation is presented. Using experimentally determined parameters, such as viscosity, specific heat, glass transition temperature (Tg), melting temperature (Tf) and heat of fusion, the temperatures of maximum crystal nucleation rates, Tmax, were calculated for several glass forming systems and compared with experimental data. It is shown that both theories give a good estimate for Tmax. For systems which do not show volume (homogeneous) nucleation, Tmax is lower than Tg. For systems which show volume nucleation, Tmax >Tg. It is concluded that both theories can be used to predict the occurrence of internal crystal nucleation in glasses and that, in general, a high value of Tg (Tg/Tf > 0.58) indicates the absence of internal nucleation.

A 3-year study on occurrence of emerging contaminants in an urban stream of São Paulo State of Southeast Brazil.

Abstract: This manuscript reports a 3-year study on occurrence of pharmaceuticals, hormones, and triclosan in surface waters of a central urban region of Sao Paulo State of Southeast Brazil (the Monjolinho River in Sao Carlos). Water samples collected once at every 2 months were pre-concentrated by solid-phase extraction (SPE) and analyzed by liquid chromatography coupled with tandem mass spectrometry (LC-MS/MS). The most frequently detected compounds in higher concentrations were caffeine, paracetamol, and atenolol (maximum concentrations 129,585, 30,421, and 8199 ng L−1, respectively), while hormones estrone and 17-β-estradiol were the least detected, in levels up to 14.8 ng L−1. There was an increasing trend in concentrations of most of the compounds along the river course, especially downstream of the river where there is discharge of both wastewater treatment plant effluent and raw sewage from a particular region of Sao Carlos city. Concentrations of contaminants were higher during dry periods as a result of decline in the water levels. Decrease in concentrations near the river mouth occurred to different extents for each compound. It was high for caffeine and atenolol, but was very low for carbamazepine and diclofenac. The present study reports the first data about the occurrence of some major emerging contaminants in the Monjolinho River. Besides its regional significance, this work may assist in composing a dataset for water contamination diagnosis focusing on emerging contaminants, both in the Brazilian as well as in the Global studies related to aquatic ecosystems. Such datasets can be helpful for making future public policies on water quality, since these compounds are not yet legally regulated.