Investigations on selected chalcogenide glasses towards the realization of photonic devices

Among various optical sensing schemes, infrared spectroscopy is a powerful tool for detecting and determining the composition of complex organic samples since vibrational finger prints of all biomolecules and organic species are located in this window. This spectroscopic technique is simple, reliable, fast, non-destructive, cost-effective while having low sensitivity. Use of metallic nanoparticles in association with a good IR transparent sensing substrate, is one of the promising solutions to enhance the sensitivity. Chalcogenide glasses are promising substrate material because of their extended optical transmission window starting from the visible to the far infrared range up to 20 μm, high refractive index usually between 2 and 3 and high optical nonlinearity, which make them good candidates as IR sensors and optical ultrafast nonlinear devices. These glasses are favorable sensor materials for the infrared spectral range because of their high IR transparency to allow for low optical loss at wavelengths corresponding to the characteristic optical absorption bands of organic molecules, high refractive index for tight confinement of optical energy within the resonator structure, processibility into thin film form, chemical compatibility for adhesion of silver nano particles and thin films and resistance to the chemical environment to be sensed. Molecules adsorbed to silver island structures shows enhanced IR absorption spectra and the extent of enhancement is determined by many factors such as the size, density and morphology of silver structures, optical and dielectric properties of the substrate material etc.

Numerical Simulation Of Ultrasonic Wave Propagation In Elastically Anisotropic Media

The ultrasonic non-destructive testing of components may encounter considerable difficulties to interpret some inspections results mainly in anisotropic crystalline structures. A numerical method for the simulation of elastic wave propagation in homogeneous elastically anisotropic media, based on the general finite element approach, is used to help this interpretation. The successful modeling of elastic field associated with NDE is based on the generation of a realistic pulsed ultrasonic wave, which is launched from a piezoelectric transducer into the material under inspection. The values of elastic constants are great interest information that provide the application of equations analytical models, until small and medium complexity problems through programs of numerical analysis as finite elements and/or boundary elements. The aim of this work is the comparison between the results of numerical solution of an ultrasonic wave, which is obtained from transient excitation pulse that can be specified by either force or displacement variation across the aperture of the transducer, and the results obtained from a experiment that was realized in an aluminum block in the IEN Ultrasonic Laboratory. The wave propagation can be simulated using all the characteristics of the material used in the experiment evaluation associated to boundary conditions and from these results, the comparison can be made.

Ultrassonic Analysis of UO2 Pellets

Ceramic materials have been widely used for various purposes in many different industries due to certain characteristics, such as high melting point and high resistance to corrosion. In the nuclear area, ceramics are of great importance due to the process of fabrication of fuel pellets for nuclear reactors. Generally, high accuracy destructive techniques are used to characterize nuclear materials for fuel fabrication. These techniques usually require costly equipment and facilities, as well as experienced personnel. This paper aims at presenting an analysis methodology for UO2 pellets using a non-destructive ultrasonic technique for porosity measurement. This technique differs from traditional ultrasonic techniques in the sense it uses ultrasonic pulses in frequency domain instead of time domain. Therefore, specific characteristics of the analyzed material are associated with the obtained frequency spectrum. In the present work, four fuel grade UO2 pellets were analyzed and the corresponding results evaluated.

Ultrasonic Spectral Analysis for Nuclear Fuel Characterization

Ceramic materials have been widely used for various purposes in many different industries due to certain characteristics, such as high melting point and high resistance to corrosion. Concerning the areas of applications, automobile, aeronautics, naval and even nuclear, the characteristics of these materials should be strictly controlled. In the nuclear area, ceramics are of great importance once they are the nuclear fuel pellets and must have, among other features, a well controlled porosity due to mechanical strength and thermal conductivity required by the application. Generally, the techniques used to characterize nuclear fuel are destructive and require costly equipment and facilities. This paper aims to present a nondestructive technique for ceramic characterization using ultrasound. This technique differs from other ultrasonic techniques because it uses ultrasonic pulse in frequency domain instead of time domain, associating the characteristics of the analyzed material with its frequency spectrum. In the present work, 40 Alumina (Al2O3) ceramic pellets with porosities ranging from 5% to 37%, in absolute terms measured by Archimedes technique, were tested. It can be observed that the frequency spectrum of each pellet varies according to its respective porosity and microstructure, allowing a fast and non-destructive association of the same characteristics with the same spectra pellets.

Analysis of Ultrasonic Techniques for the Characterization of Microfiltration Polymeric Membranes

The use of polymeric membranes is extremely important in several industries such as nuclear, biotechnology, chemical and pharmaceutical. In the nuclear area, for instance, systems based on membrane separation technologies are currently being used in the treatment of radioactive liquid effluent, and new technologies using membranes are being developed at a great rate. The knowledge of the physical characteristics of these membranes, such as, pore size and the pore size distribution, is very important to the membranes separation processes. Only after these characteristics are known is it possible to determine the type and to choose a particular membrane for a specific application. In this work, two ultrasonic non destructive techniques were used to determine the porosity of membranes: pulse echo and transmission. A 25 MHz immersion transducer was used. Ultrasonic signals were acquired, for both techniques, after the ultrasonic waves passed through a microfiltration polymeric membrane of pore size of 0.45 μm and thickness of 180 μm. After the emitted ultrasonic signal crossed the membrane, the received signal brought several information on the influence of the membrane porosity in the standard signal of the ultrasonic wave. The ultrasonic signals were acquired in the time domain and changed to the frequency domain by application of the Fourier Fast Transform (FFT), thus generating the material frequency spectrum. For the pulse echo technique, the ultrasonic spectrum frequency changed after the ultrasonic wave crossed the membrane. With the transmission technique there was only a displacement of the ultrasonic signal at the time domain.

Oil Flow Rate Measurements Using 198au And Total Count Technique

In industrial plants, oil and oil compounds are usually transported by closed pipelines with circular cross-section. The use of radiotracers in oil transport and processing industrial facilities allows calibrating flowmeters, measuring mean residence time in cracking columns, locate points of obstruction or leak in underground ducts, as well as investigating flow behavior or industrial processes such as in distillation towers. Inspection techniques using radiotracers are non-destructive, simple, economic and highly accurate. Among them, Total Count, which uses a small amount of radiotracer with known activity, is acknowledged as an absolute technique for flow rate measurement. A viscous fluid transport system, composed by four PVC pipelines with 13m length (12m horizontal and 1m vertical) and ½, ¾, 1 and 2-inch gauges, respectively, interconnected by maneuvering valves was designed and assembled in order to conduct the research. This system was used to simulate different flow conditions of petroleum compounds and for experimental studies of flow profile in the horizontal and upward directions. As 198Au presents a single photopeak (411,8 keV), it was the radioisotope chosen for oil labeling, in small amounts (6 ml) or around 200 kBq activity, and it was injected in the oil transport lines. A NaI scintillation detector 2”x 2”, with well-defined geometry, was used to measure total activity, determine the calibration factor F and, positioned after a homogenization distance and interconnected to a standardized electronic set of nuclear instrumentation modules (NIM), to detect the radioactive cloud.

Infrared image enhancement based on hybrid-domain consideration and data fusion methods

Au cours des dernières décennies, l’effort sur les applications de capteurs infrarouges a largement progressé dans le monde. Mais, une certaine difficulté demeure, en ce qui concerne le fait que les objets ne sont pas assez clairs ou ne peuvent pas toujours être distingués facilement dans l’image obtenue pour la scène observée. L’amélioration de l’image infrarouge a joué un rôle important dans le développement de technologies de la vision infrarouge de l’ordinateur, le traitement de l’image et les essais non destructifs, etc. Cette thèse traite de la question des techniques d’amélioration de l’image infrarouge en deux aspects, y compris le traitement d’une seule image infrarouge dans le domaine hybride espacefréquence, et la fusion d’images infrarouges et visibles employant la technique du nonsubsampled Contourlet transformer (NSCT). La fusion d’images peut être considérée comme étant la poursuite de l’exploration du modèle d’amélioration de l’image unique infrarouge, alors qu’il combine les images infrarouges et visibles en une seule image pour représenter et améliorer toutes les informations utiles et les caractéristiques des images sources, car une seule image ne pouvait contenir tous les renseignements pertinents ou disponibles en raison de restrictions découlant de tout capteur unique de l’imagerie. Nous examinons et faisons une enquête concernant le développement de techniques d’amélioration d’images infrarouges, et ensuite nous nous consacrons à l’amélioration de l’image unique infrarouge, et nous proposons un schéma d’amélioration de domaine hybride avec une méthode d’évaluation floue de seuil amélioré, qui permet d’obtenir une qualité d’image supérieure et améliore la perception visuelle humaine. Les techniques de fusion d’images infrarouges et visibles sont établies à l’aide de la mise en oeuvre d’une mise en registre précise des images sources acquises par différents capteurs. L’algorithme SURF-RANSAC est appliqué pour la mise en registre tout au long des travaux de recherche, ce qui conduit à des images mises en registre de façon très précise et des bénéfices accrus pour le traitement de fusion. Pour les questions de fusion d’images infrarouges et visibles, une série d’approches avancées et efficaces sont proposés. Une méthode standard de fusion à base de NSCT multi-canal est présente comme référence pour les approches de fusion proposées suivantes. Une approche conjointe de fusion, impliquant l’Adaptive-Gaussian NSCT et la transformée en ondelettes (Wavelet Transform, WT) est propose, ce qui conduit à des résultats de fusion qui sont meilleurs que ceux obtenus avec les méthodes non-adaptatives générales. Une approche de fusion basée sur le NSCT employant la détection comprime (CS, compressed sensing) et de la variation totale (TV) à des coefficients d’échantillons clairsemés et effectuant la reconstruction de coefficients fusionnés de façon précise est proposée, qui obtient de bien meilleurs résultats de fusion par le biais d’une pré-amélioration de l’image infrarouge et en diminuant les informations redondantes des coefficients de fusion. Une procédure de fusion basée sur le NSCT utilisant une technique de détection rapide de rétrécissement itératif comprimé (fast iterative-shrinking compressed sensing, FISCS) est proposée pour compresser les coefficients décomposés et reconstruire les coefficients fusionnés dans le processus de fusion, qui conduit à de meilleurs résultats plus rapidement et d’une manière efficace.

Opiniões sobre a visita de enfermagem em unidades de cirurgia: tradução, adaptação e validação de questionários

Enquadramento: Apesar da visita de enfermagem ou passagem de turno junto dos doentes garantir a continuidade dos cuidados de enfermagem, origina diversas questões éticas. Objetivos: Traduzir, adaptar e validar 2 questionários de colheita de dados sobre a visita de enfermagem em unidades cirúrgicas para a cultura portuguesa; identificar a opinião dos doentes e dos enfermeiros sobre a visita de enfermagem. Metodologia: Tradução, retroversão e adaptação dos questionários aplicados em 7 unidades cirúrgicas de um hospital central em Portugal de 22/08/2008 a 28/06/2009. A amostragem não probabilística acidental foi constituída por 137 enfermeiros e 96 doentes. Resultados: A visita de enfermagem promove a relação empática e de ajuda; a observação do doente e o planeamento de cuidados, no entanto é necessário clarificar o seu objetivo; incentivar à participação e ao envolvimento dos doentes; utilizar um discurso compreensível e garantir a privacidade da informação. Conclusão: Os questionários revelaram-se fidedignos e válidos na identificação das opiniões dos doentes e dos enfermeiros sobre a visita de enfermagem nas unidades de cirurgia em estudo.Background: Although bedside nursing handover ensures the continuity of nursing care, it raises several ethical issues. Objectives: To translate, adapt and validate 2 data collection questionnaires about bedside nursing handover in surgical units into Portuguese, and identify the patients and nurses’ opinions about bedside nursing handover. Methodology: Translation, back-translation and adaptation of the questionnaires in 7 surgical units of a central hospital in Portugal between 22/08/2008 and 28/06/2009. The non- -probability sampling consisted of 137 nurses and 96 patients. Results: Bedside nursing handover promotes an empathic and helping relationship, patient observation and care planning; however, it is necessary to clarify its purpose, encourage patient participation and engagement, use clear information, and ensure information privacy. Conclusion: The questionnaires proved to be reliable and valid to identify the patients and nurses’ opinions about bedside nursing handover in the surgical units under analysis.

Physical and chemical kinetics of structural build-up of cement suspensions

Abstract : The structural build-up of fresh cement-based materials has a great impact on their structural performance after casting. Accordingly, the mixture design should be tailored to adapt the kinetics of build-up given the application on hand. The rate of structural build-up of cement-based suspensions at rest is a complex phenomenon affected by both physical and chemical structuration processes. The structuration kinetics are strongly dependent on the mixture’s composition, testing parameters, as well as the shear history. Accurate measurements of build-up rely on the efficiency of the applied pre-shear regime to achieve an initial well-dispersed state as well as the applied stress during the liquid-solid transition. Studying the physical and chemical mechanisms of build-up of cement suspensions at rest can enhance the fundamental understanding of this phenomenon. This can, therefore, allow a better control of the rheological and time-dependent properties of cement-based materials. The research focused on the use of dynamic rheology in investigating the kinetics of structural build-up of fresh cement pastes. The research program was conducted in three different phases. The first phase was devoted to evaluating the dispersing efficiency of various disruptive shear techniques. The investigated shearing profiles included rotational, oscillatory, and combination of both. The initial and final states of suspension’s structure, before and after disruption, were determined by applying a small-amplitude oscillatory shear (SAOS). The difference between the viscoelastic values before and after disruption was used to express the degree of dispersion. An efficient technique to disperse concentrated cement suspensions was developed. The second phase aimed to establish a rheometric approach to dissociate and monitor the individual physical and chemical mechanisms of build-up of cement paste. In this regard, the non-destructive dynamic rheometry was used to investigate the evolutions of both storage modulus and phase angle of inert calcium carbonate and cement suspensions. Two independent build-up indices were proposed. The structural build-up of various cement suspensions made with different cement contents, silica fume replacement percentages, and high-range water reducer dosages was evaluated using the proposed indices. These indices were then compared to the well-known thixotropic index (Athix.). Furthermore, the proposed indices were correlated to the decay in lateral pressure determined for various cement pastes cast in a pressure column. The proposed pre-shearing protocol and build-up indices (phases 1 and 2) were then used to investigate the effect of mixture’s parameters on the kinetics of structural build-up in phase 3. The investigated mixture’s parameters included cement content and fineness, alkali sulfate content, and temperature of cement suspension. Zeta potential, calorimetric, spectrometric measurements were performed to explore the corresponding microstructural changes in cement suspensions, such as inter-particle cohesion, rate of Brownian flocculation, and nucleation rate. A model linking the build-up indices and the microstructural characteristics was developed to predict the build-up behaviour of cement-based suspensions The obtained results showed that oscillatory shear may have a greater effect on dispersing concentrated cement suspension than the rotational shear. Furthermore, the increase in induced shear strain was found to enhance the breakdown of suspension’s structure until a critical point, after which thickening effects dominate. An effective dispersing method is then proposed. This consists of applying a rotational shear around the transitional value between the linear and non-linear variations of the apparent viscosity with shear rate, followed by an oscillatory shear at the crossover shear strain and high angular frequency of 100 rad/s. Investigating the evolutions of viscoelastic properties of inert calcite-based and cement suspensions and allowed establishing two independent build-up indices. The first one (the percolation time) can represent the rest time needed to form the elastic network. On the other hand, the second one (rigidification rate) can describe the increase in stress-bearing capacity of formed network due to cement hydration. In addition, results showed that combining the percolation time and the rigidification rate can provide deeper insight into the structuration process of cement suspensions. Furthermore, these indices were found to be well-correlated to the decay in the lateral pressure of cement suspensions. The variations of proposed build-up indices with mixture’s parameters showed that the percolation time is most likely controlled by the frequency of Brownian collisions, distance between dispersed particles, and intensity of cohesion between cement particles. On the other hand, a higher rigidification rate can be secured by increasing the number of contact points per unit volume of paste, nucleation rate of cement hydrates, and intensity of inter-particle cohesion.

The Effect of Mark Enhancement Techniques on the Subsequent Detection of Saliva

There appears to be a limited but growing body of research on the sequential analysis/treatment of multiple types of evidence. The development of an integrated forensic approach is necessary to maximise evidence recovery and to ensure that a particular treatment is not detrimental to other types of evidence. This study aims to assess the effect of latent and blood mark enhancement techniques (e.g. fluorescence, ninhydrin, acid violet 17, black iron-oxide powder suspension) on the subsequent detection of saliva. Saliva detection was performed by means of a presumptive test (Phadebas®) in addition to analysis by a rapid stain identification (RSID) kit test and confirmatory DNA testing. Additional variables included a saliva depletion series and a number of different substrates with varying porosities as well as different ageing periods. Examination and photography under white light and fluorescence was carried out prior to and after chemical enhancement All enhancement techniques (except Bluestar® Forensic Magnum luminol) employed in this study resulted in an improved visualisation of the saliva stains, although the inherent fluorescence of saliva was sometimes blocked after chemical treatment. The use of protein stains was, in general, detrimental to the detection of saliva. Positive results were less pronounced after the use of black iron-oxide powder suspension, cyanoacrylate fuming followed by BY40 and ninhydrin when compared to the respective positive controls. The application of Bluestar® Forensic Magnum luminol and black magnetic powder proved to be the least detrimental, with no significant difference between the test results and the positive controls. The use of non-destructive fluorescence examination provided good visualisation; however, only the first few marks in the depletion were observed. Of the samples selected for DNA analysis only depletion 1 samples contained sufficient DNA quantity for further processing using standard methodology. The 28 day delay between sample deposition and collection resulted in a 5-fold reduction in the amount of useable DNA. When sufficient DNA quantities were recovered, enhancement techniques did not have a detrimental effect on the ability to generate DNA profiles. This study aims to contribute to a strategy for maximising evidence recovery and efficiency for the detection of latent marks and saliva. The results demonstrate that most of the enhancement techniques employed in this study were not detrimental to the subsequent detection of saliva by means of presumptive, confirmative and DNA tests.

Referenciação de crianças com problemas de comunicação e linguagem a partir dos cuidados de saúde primários

Os problemas de comunicação e linguagem (PCL) podem limitar a atividade e participação de um indivíduo ao longo da sua vida. Todavia, a intervenção precoce tem-se provado bastante eficaz nestes casos. Os médicos de família (MF) encontram-se numa posição privilegiada para deteção e referenciação destes problemas em idades precoces. Porém, há evidências de que a sua participação neste processo tem sido reduzida, nomeadamente no que respeita à referenciação para serviços de Intervenção Precoce. Assim, esta investigação pretende compreender qual o papel que os MF consideram ter relativamente a este processo e quais os fatores que podem influenciar a referenciação de crianças com suspeita de PCL. Este estudo teve como base um desenho de investigação descritivo, transversal e observacional. Recorreu-se a um método de amostragem por redes para a distribuição de um questionário On-line. O instrumento foi construído pela autora e é de caráter maioritariamente quantitativo, embora integre uma questão qualitativa de resposta semiaberta. Dos questionários enviados foram devolvidos 55. A resposta semiaberta foi preenchida por 16 dos 55 MF. Os resultados demonstram que a maioria dos MF valoriza bastante ou muito a sua participação na deteção de PCL e considera importante detetar precocemente estes problemas. Para além disso, valorizam bastante ou muito a colaboração em equipa e do terapeuta da fala. A grande parte sente-se influenciada pela preocupação dos pais, pela satisfação com os serviços e com os resultados da Escala de Avaliação de Desenvolvimento de Mary Sheridan Modificada para a referenciação de crianças com PCL. Para além disso, identificam barreiras relacionadas com recursos humanos, serviços, conhecimentos relacionados com o processo de referenciação, burocracia, lentidão do processo e com a atitude dos pais. Considera-se que este estudo pode constituir um ponto de partida para futuras investigações, para a adequação de estratégias institucionais e implementação de práticas que aproximem profissionais e serviços, de forma a melhorar o processo de referenciação de crianças com PCL a partir dos cuidados de saúde primários.

Selection for muscle fat content and triploidy affect flesh quality in pan-size rainbow trout, Oncorhynchus mykiss

A lean muscle line (L) and a fat muscle line (F) of rainbow trout were established (Quillet et al., 2005) by a two-way selection for muscle lipid content performed on pan-size rainbow trout using a non-destructive measurement of muscle lipid content (Distell Fish Fat Meter®). The aim of the present study was to evaluate the consequences of this selective breeding on flesh quality of pan size (290 g) diploid and triploid trout after three generations of selection. Instrumental evaluations of fillet color and pH measurement were performed at slaughter. Flesh color, pH, dry matter content and mechanical resistance were measured at 48 h and 96 h postmortem on raw and cooked flesh, respectively. A sensorial profile analysis was performed on cooked fillets. Fillets from the selected fatty muscle line (F) had a higher dry matter content and were more colorful for both raw and cooked fillets. Mechanical evaluation indicated a tendency of raw flesh from F fish to be less firm, but this was not confirmed after cooking, neither instrumentally or by sensory analysis. The sensory analysis revealed higher fat loss, higher intensity of flavor of cooked potato, higher exudation, higher moisture content and a more fatty film left on the tongue for flesh from F fish. Triploid fish had mechanically softer raw and cooked fillets, but the difference was not perceived by the sensorial panel. The sensorial evaluation also revealed a lower global intensity of odor, more exudation and a higher moisture content in the fillets from triploid fish. These differences in quality parameters among groups of fish were associated with larger white muscle fibers in F fish and in triploid fish. The data provide additional information about the relationship between muscle fat content, muscle cellularity and flesh quality.

Opiniões sobre a visita de enfermagem em unidades de cirurgia: tradução, adaptação e validação de questionários

Enquadramento: Apesar da visita de enfermagem ou passagem de turno junto dos doentes garantir a continuidade dos cuidados de enfermagem, origina diversas questões éticas. Objetivos: Traduzir, adaptar e validar 2 questionários de colheita de dados sobre a visita de enfermagem em unidades cirúrgicas para a cultura portuguesa; identificar a opinião dos doentes e dos enfermeiros sobre a visita de enfermagem. Metodologia: Tradução, retroversão e adaptação dos questionários aplicados em 7 unidades cirúrgicas de um hospital central em Portugal de 22/08/2008 a 28/06/2009. A amostragem não probabilística acidental foi constituída por 137 enfermeiros e 96 doentes. Resultados: A visita de enfermagem promove a relação empática e de ajuda; a observação do doente e o planeamento de cuidados, no entanto é necessário clarificar o seu objetivo; incentivar à participação e ao envolvimento dos doentes; utilizar um discurso compreensível e garantir a privacidade da informação. Conclusão: Os questionários revelaram-se fidedignos e válidos na identificação das opiniões dos doentes e dos enfermeiros sobre a visita de enfermagem nas unidades de cirurgia em estudo.Background: Although bedside nursing handover ensures the continuity of nursing care, it raises several ethical issues. Objectives: To translate, adapt and validate 2 data collection questionnaires about bedside nursing handover in surgical units into Portuguese, and identify the patients and nurses’ opinions about bedside nursing handover. Methodology: Translation, back-translation and adaptation of the questionnaires in 7 surgical units of a central hospital in Portugal between 22/08/2008 and 28/06/2009. The non- -probability sampling consisted of 137 nurses and 96 patients. Results: Bedside nursing handover promotes an empathic and helping relationship, patient observation and care planning; however, it is necessary to clarify its purpose, encourage patient participation and engagement, use clear information, and ensure information privacy. Conclusion: The questionnaires proved to be reliable and valid to identify the patients and nurses’ opinions about bedside nursing handover in the surgical units under analysis.

Tensor Completion for Multidimensional Inverse Problems with Applications to Magnetic Resonance Relaxometry

This thesis deals with tensor completion for the solution of multidimensional inverse problems. We study the problem of reconstructing an approximately low rank tensor from a small number of noisy linear measurements. New recovery guarantees, numerical algorithms, non-uniform sampling strategies, and parameter selection algorithms are developed. We derive a fixed point continuation algorithm for tensor completion and prove its convergence. A restricted isometry property (RIP) based tensor recovery guarantee is proved. Probabilistic recovery guarantees are obtained for sub-Gaussian measurement operators and for measurements obtained by non-uniform sampling from a Parseval tight frame. We show how tensor completion can be used to solve multidimensional inverse problems arising in NMR relaxometry. Algorithms are developed for regularization parameter selection, including accelerated k-fold cross-validation and generalized cross-validation. These methods are validated on experimental and simulated data. We also derive condition number estimates for nonnegative least squares problems. Tensor recovery promises to significantly accelerate N-dimensional NMR relaxometry and related experiments, enabling previously impractical experiments. Our methods could also be applied to other inverse problems arising in machine learning, image processing, signal processing, computer vision, and other fields.

Controle social e políticas públicas: contribuições para aprimorar o controle social do programa nacional de alimentação escolar

The National School Feeding Programme (PNAE) is a public policy in Brazil for over 60 years and represents one of the most important programs of feeding and nutrition in the world. The role of family farming as a source of employment in rural areas, food provider and for ensuring much of the Brazil’s food security is constantly present at the government's and social movement’s agendas. Law 11.947 of 2009 marked its integration in the food supply for the National School Feeding Programme. Article 14 of aforementioned law highlights that a minimum of 30% (thirty percent) of the funds transferred by the National Development Fund Education (FNDE) to the Programme must be used for the purchase of food directly from family farmers or their organizations. The national school feeding policy under the responsibility of the FNDE and is subjected to agencies of internal control, such as the General Controllership of the Union (CGU), of external control, such as the Audit Courts of the Union and the of the states, and to the social control of the school feeding councils. Those funds are transferred to the implementing agencies, which are the education offices of the states, municipalities and of the Federal District. These entities must annually present their accountings to the School Feeding Councils, which analyze them and then issue a conclusive report to the FNDE, approving with or without reservations, or rejecting them. In this sense, this research aims to propose parameters that should contribute to the improvement of the social control over purchases from family farming for the National School Feeding Programme. The study was conducted by non parametric sampling alongside the managers of the implementing entities, school feeding councils and Family Farming Organizations all across Brazil, from the databases provided by FNDE and by the National Union of Cooperatives of Family Agriculture and Solidarity Economy (Unicafes). The study points out that the legal framework of PNAE seeks to ensure the participation of family farming in the food supply for the Programme, despite allowing the executing agencies to justify the non-compliance of the minimum required in a number of ways. The survey also signalizes that the school feeding councils follow the implementation of the Programme very shyly, and points out that there is room to expand and enhance the participation of these councils and organizations of family farming in the execution of PNAE. Its effectiveness requires a constant and effective process of training of the agents involved in the Programme.