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  • Determination of the validation parameters of inductively coupled plasma mass spectrometer (iCP-mS): response curve linearity in the case of arsenic and selenium
    67-71
    Views:
    129

    In the field of elemental analysis inductively coupled plasma mass spectrometers (ICP-MS) have the best sensitivity that means the lowest limit of detection, subsequently their applicability for the detection of essential and toxic elements in foods and foodstuffs is prominent. For the most elements could be measured the detection limit is between μg kg-1 (ppb) and ng kg-1 (ppt) e.g. for arsenic and selenium.

    Considering an analytical task (sample type, analytes and their concentration, pretreatment procedure etc.) the applicability of an analytical method is determined by its performance characteristics. The purpose of validation is to ensure that the method would be used fulfills the requirements of the given task. In this article we describes one of the performance characteristics, the linearity, and the whole validation procedure aims measurement of arsenic and selenium in foodstuffs by inductively coupled plasma mass spectrometer (Thermo XSeries I.); but because of the limited number of pages the results are demonstrated only for arsenic.

    The linearity of calibration was evaluated in three concentration ranges (0.1–1 μg l-1; 1–10 μg l-1; 10–50 μg l-1), with nine line-fit possibilities (without weighting, weighting with absolute or relative deviation; with or without forcing the curve through blank or origin) and different methods (graphical examination, correlation coefficient, analysis of variance).

    The best method to ensure the linearity of correspondence between signal and concentration was the ANOVA test. In view of calibrations it was found that the range of 10–50 μg l-1 could be regarded as linear with four line-fit possibilities, and was non-linear between 0.1–1 μg l-1 and 1–10 μg l-1.

  • Validation of the competence profile of agri-environmental engineering bachelor course
    63-71
    Views:
    149

    As member of the European Union, the development if the Hungarian agriculture is determined by the Common Agricultural Policy. After the reform of the Common Agricultural Policy in 2003, the environmental protection has got a crucial function. The constant changing role of agriculture has reacted students in higher education. For firms connected to agriculture, human resource management based on competency has an important role in custody of competitiveness. One of the most important goals of firms is to supply the demands of their economic partners. To make it successfully, highly qualified human resource is required. The quality of human resource is determined not only by its qualification, language skills, professional experience, and practise, but extant competencies that can also be developed. To choose the expectant employee, it is not enough for them to have intelligence and proficiency; it is also decisive to examine their particular competencies. All of these will define the employee’s
    achievement that will definitely contribute to the success of the enterprise. Basically, closer cooperation is needed between higher education institutions and employers to achieve this goal. At the same time, the higher education institutions can revise their training systems considering the actual requirements of labour market, and accordingly, they can form syllabus in a way to train auspicious experts. In this article examination of the requirements of labour market for graduates from agri-environmental engineering bachelor course is presented.

  • Biomass production estimation of processing tomato using AquaCrop under different irrigation treatments
    131-136
    Views:
    185

    The wiser usage of irrigation water is inevitable in the future. Irrigation has very high input cost; therefore, farmers must carry out irrigation with care. Also, the effect of irrigation on crops has a big role in decision making. Modeling provides a possibility to evaluate this effect. AquaCrop, as a crop production simulation model has great potential in this field. The accuracy of tomato biomass yield prediction of the model was tested in this research. For collecting the necessary data, a field experiment was conducted at Szarvas on processing tomato with different water supplies, such as 100% (I100), 75% (I75), 50% (I50) of potential evapotranspiration and a control with basic water supply (C). The relation of the simulation and actual biomass yields was evaluated during the season. Very good correlation was found between the modelled and the actually harvested data. The data for the control and I100 treatments showed higher correlation than the I75 and I50. The relationship for all of the data was moderately strong. Miscalculations occur mostly when the dry biomass yield reaches
    7 t ha-1. The accuracy of the model was evaluated with the use of mean absolute error (MAE) and root mean squared error (RMSE) values. The least error was found in the C treatment, which means 0.34 MAE and 0.45 t ha-1 RMSE. The simulation resulted in higher errors in the I75 and I50 treatments.

  • Competence modules of the agro-environmental engineering bachelor course in Hungary
    229-236
    Views:
    69

    One of the most important goals of the Bologna Process is to introduce the three circle system: bachelor, master, doctorate courses. In Hungary from 2006/2007 academic year 132 bachelor courses are launched. One of the launched bachelor course is environmental engineering of which the scientific background and economical sector are rapidly changing. Hence, to help graduates from this area to find a job, it is very important to examine working activities, expectations of employers, to study requirements of the training programs, the system of competencies. Having examined these points, frameworks of professional requirements have been worked out by 27 validation tests. In this publication, the results of the research work related to the environmental engineering bachelor program were presented.