The possibilities of the Response Surface Methodology (RSM) has been explored within the ambit of Scientific Activity Analysis. The case of the system "Departments of the Area of Health Sciences of the University of Navarre (Spain)" has been studied in relation to the system "Scientific Community in the Health Sciences", from the perspective of input/output models (factors/response). It is concluded that the RSM reveals the causal relationships between factors and responses through the construction of polynomial mathematical models. Similarly, quasi-experimental designs are proposed, these permitting scientific activity to be analysed with minimum effort and cost and high accuracy. PUBLICADO E SCIE TOMETRICS

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A method has been formulated and tested in a laboratory device to evaluate the detersive and dispersant performance, as well as the washing dynamics, of surfactants and builders and the formulation of the detergent. The method, called bath-substrate flow (BSF), is based on the separation of the washing bath from the substrate to be washed after contact of the two by a cyclic-flow process. The method serves to analyze mechanical washing systems, such as dishwashers, tunnel washes, floor-washing machines, and industrial-scale cleaning systems. The circumscribed central compound experimental design was applied, as was the response surface method, to correlate the detergency values found.

Detersive processes are complex systems involving a great number of variables. To determine the effect of these variables on the washing of hard surfaces and fatty soils is the object of this work. The statistical design of experiments has been used to evaluate the influence of factors such as temperature, soil concentration and surfactant concentration on detergency. The experimental trials have been made in a continuous-flow device where the soiling agent is confined in a column filled with borosilicate glass spheres. Solutions of the commercial surfactant Berol Ó LFG61 (a mixture of alkylpolyglucosides and fatty-alcohol ethoxylates) have been employed as the wash bath. Both the design of experiments and the continuous experimental system used proved to be an effective tool for detecting the key variables in the cleaning process. Expressions were developed to simulate detergency levels as a function of the variables assayed, always inside the experimental domain. In the trials with oleic acid as the soiling agent, it was found that the temperature and soil concentration were the most important variables to take into account, while the surfactant concentration was not a significant variable. When a semi-solid mixture of different fatty acids was employed, all the variables assayed proved significant, with high detergency values being reached by combining temperature and surfactant concentrations. Results clearly show that the effectiveness of the surfactant used is influenced by the type and concentration of the soil and thus the intended application of the product being developed should be taken into account when designing detergent formulas.

The kinetics of fatty soil removal from glass surfaces using nonionic biodegradable surfactants has been investigated. For this, mathematical models have been developed, which take into account the equilibrium established between the processes of soil removal from the substrate surface and their subsequent redeposition. The washing tests have been conducted in a continuous-flow device that simulates the conditions found in the clean-inplace system used in the food industry. A mixture of fatty acids (oleic, palmitic and stearic) frequently found in foods, and particularly difficult to remove, was used as the soiling agent. The experimental results show the effect of the different variables assayed (temperature, soiling-agent concentration and surfactant concentration) on the washing process. The good agreement between the experimental detergency values and those predicted by the kinetic model indicate that this is adequate to explain the detersive process on hard surfaces. PRACTICAL APPLICATIONSIn food industry, production lines are cleaned in place every day to provide the microbial quality and safety of the products. Moreover, the effectiveness of the cleaning process depends on many factors: temperature, detergent concentrations, hydrodynamic forces, characteristics of substrate, etc. In this work, we have studied the kinetics of the washing process using alkylpolyglucosides and fatty alcohol ethoxylates, both commercial surfactants.The tests were performed in a laboratory device that simulates the clean-in-1 Corresponding place processes widely used in food industries. A mixture of fatty acids commonly found in foods was used as the soiling agent. A kinetic model assuming a process combining removal and deposition during the cleaning was developed. This model, which satisfactorily predicts the detergency data obtained under different experimental conditions, could be of great practical utility since it can help develop more effective detergent formulations. 1054 E.J. ALAMEDA ET AL.