Avaliação das condições de precipitação do azul da Prússia sobre pó de grafite visando o desenvolvimento de eletrodos de pasta de carbono para a quantificação de nitrito

An amperometric FIA method for nitrite quantification based on nitrite electroreduction and employing a carbon paste electrode (CPE) chemically modified with iron hexacyanoferrate (HCF) as an amperometric detector was developed. The influence of experimental conditions on the preparation of the electrode materials was evaluated and the materials obtained in each study were used for the development of modified electrodes. The electrochemical sensors were prepared by a fast, simple, and inexpensive procedure, and the long-term performance of the electrodes were quite satisfactory as the stability was maintained over one year. HCF was an effective redox mediator for nitrite electroreduction in acidic media, allowing nitrite detection at +0.2 V vs. Ag/AgClsat, which is a potential free of possible interfering species that are normally present in food and water samples. The electrochemical cell used in the FIA system was similar to a batch injection analysis cell, enabling recirculation of the carrier solution. This is an attractive feature because it allows the use of a high flow rate (6 mL min-1) leading to high sensitivity and analysis speed, while keeping reagent consumption low. The proposed method had a detection limit of 9 μmol L-1 and was successfully employed for nitrite quantification in spiked water and sausage samples. The obtained results were in good agreement with those provided by the spectrophotometric official method. At a 95 % confidence level it was not observed statistical differences neither in nitrite content nor in the precision provided by both methods. The experimental conditions for the synthesis of HCF were optimized and the best electrode material was prepared by mixing FeCl3, K4[Fe(CN)6] and carbon powder subjected to an acid and thermal treatment (400 ºC), followed by ultrasonic agitation at 4 °C. This material was used to construct an electrode with improved analytical performance to reduce nitrite, which presented greater stability compared to HCF film electrodeposited on the EPC, showing that the preparation procedure of the electrode material is an effective strategy for the development of HCF modified electrodes.

Impacto do trabalho noturno na qualidade de vida do profissional de enfermagem do gênero masculino

The nursing staff is now the largest contingent of professionals in healthcare environments, with more than 1.8 million professionals, and of these 15% are men, showing a masculinization of the historical profession and culturally conceived and carried out by women (COFEN / FIOCRUZ, 2013). This dissertation discusses the profession forward to some issues related to gender, quality of life and night work. Objective: To analyze the impact that shift work has the professional quality of life male, through a specific instrument to identify the main problems and joint damage to that front group to his professional activity. Methods: descriptivo, Cross-sectional study with a quantitative approach, performed with 72 professional male nursing staff, 41 (56.9%) nursing technicians, 18 (25%) of nursing assistants and 13 (18.1%) of nurses, in January 2015 in a university hospital in the city of Uberlândia (Minas Gerais). For this, we used the WHOQOL-BREF questionnaire. Quantitative variables were described as mean, standard deviation, maximum and minimum, in addition to the Shapiro-Wilk test and Kruskal-Wallis used in the data analysis, with a confidence level of 5% (p <0.05). Results: the profile of respondents, most are married 42 (58.3%) under the employment contract via Single Legal Regime 50 (69.4%) with mean age of 40 and having 16 years of service; and within a range of 0 to 100, the areas with better evaluation were the Social Relations (70.1) and psychological (67.5); already the worst were the Environment (57.4) and Physical (65.4). In the overall assessment, the average was 63.3 and staying below the national average (65-70). Thus, the professionals who were married obtained better scores, regardless of the category which is in the nursing team. Conclusions: The group is average, taking into account the standard deviation, but we can say that working conditions affect their profession, and these results allow the detection of the difficulties experienced by men of the nursing team, and can cooperate with the design strategies that benefit or minimize the search for conflicts that affect the health of these workers and their quality of life.