Biosorción en tanque agitado de Cd(+2) y Pb(+2) con cáscara de cacao

En la búsqueda de tecnologías más limpias para el tratamiento de efluentes que contienen metales pesados se ha dirigido la atención hacia la biosorción. Este estudio permitió abordar el proceso de biosorción de 〖Cd〗^(+2)y 〖Pb〗^(+2) en efluentes mineros a través de la cáscara de cacao. Se determinó las características físico-químicas del biosorbente y el resultado obtenido fue: la cáscara de cacao tiene una superficie neutra, compuesta principalmente por grupos ésteres alifáticos; además se estudió los factores que afectan este proceso como son: pH, tamaño de partícula, tiempo de contacto, Temperatura, y la concentración inicial del metal. El pH óptimo para la biosorción de plomo es entre 4 y 5 y para el cadmio fue entre 5 y 6; con respecto al tiempo de contacto necesario para eliminar la mayor cantidad de iones metálicos fue de 10 minutos, siendo el resultado obtenido en la remoción tanto de cadmio como de plomo de 86,92% y 96,74% respectivamente. Se observó que la temperatura no afecta significativamente el proceso de biosorción como el pH y se determinó como óptima 25℃ ; también se analizó que la cáscara de cacao tiene mayor afinidad por el cadmio por tener un radio iónico más pequeño que el plomo permitiéndole alcanzar poros reducidos; además al aumentar la concentración, la eliminación de cadmio disminuyó y para el plomo aumentó pero no de forma significativa. Los datos experimentales de la biosorción de plomo y cadmio en cáscara de cacao, reproducen favorablemente el modelo cinético Pseudo Segundo Orden, con coeficientes de correlación (R^2) para 〖Pb〗^(+2) de 0,999 y 〖Cd〗^(+2) de 1. Finalmente en el estudio de equilibrio el modelo de Langmuir describe el proceso de adsorción para 〖Cd〗^(+2) y el modelo de Fleundlich se ajustó mejor a los datos experimentales para 〖Pb〗^(+2).

IMPROVED SAMPLE INTRODUCTION SYSTEMS FOR INDUCTIVELY COUPLED PLASMA OPTICAL EMISSION SPECTROMETRY AND THEIR APPLICATION TO THE ANALYSIS OF SIMPLE AND COMPLEX MATRICES

The objective of this thesis is to explore new and improved methods for greater sample introduction efficiency and enhanced analytical performance with inductively coupled plasma optical emission spectrometry (ICP-OES). Three projects are discussed in which the capabilities and applications of ICP-OES are expanded: 1. In the first project, a conventional ultrasonic nebuliser was modified to replace the heater/condenser with an infrared heated pre-evaporation tube. In continuation from previous works with pre-evaporation, the current work investigated the effects of heating with infrared block and rope heaters on two different ICP-OES instruments. Comparisons were made between several methods and setups in which temperatures were varied. By monitoring changes to sensitivity, detection limit, precision, and robustness, and analyzing two certified reference materials, a method with improved sample introduction efficiency and comparable analytical performance to a previous method was established. 2. The second project involved improvements to a previous work in which a multimode sample introduction system (MSIS) was modified by inserting a pre-evaporation tube between the MSIS and torch. The new work focused on applying an infrared heated ceramic rope for pre-evaporation. This research was conducted in all three MSIS modes (nebulisation mode, hydride generation mode, and dual mode) and on two different ICP-OES instruments, and comparisons were made between conventional setups in terms of sensitivity, detection limit, precision, and robustness. By tracking both hydride-forming and non-hydride forming elements, the effects of heating in combination with hydride generation were probed. Finally, optimal methods were validated by analysis of two certified reference materials. 3. A final project was completed in collaboration with ZincNyx Energy Solutions. This project sought to develop a method for the overall analysis of a 12 M KOH zincate fuel, which is used in green energy backup systems. By employing various techniques including flow injection analysis and standard additions, a final procedure was formulated for the verification of K concentration, as well as the measurement of additives (Al, Fe, Mg, In, Si), corrosion products (such C from CO₃²¯), and Zn particles both in and filtered from solution. Furthermore, the effects of exposing the potassium zincate electrolyte fuel to air were assessed.

Design and characterization of wideband Hall current sensors in BCD technology for smart power and metering applications

Power electronic circuits are moving towards higher switching frequencies, exploiting the capabilities of novel devices to shrink the dimension of passive components. This trend demands sensors capable enough to operate at such high frequencies. This thesis aims to demonstrate through experimental characterization, the broadband capability of a fully integrated CMOS X-Hall current sensor in current mode interfaced with a transimpedance amplifier (TIA), chip CH09, realized in CMOS technology for power electronics applications such as power converters. The system exploits a common-mode control system to operate the dual supply system, 5-V for the X-Hall probe and 1.2-V for the readout. The developed prototype achieves a maximum acquisition bandwidth of 12 MHz, a power consumption of 11.46 mW, resolution of 39 mArms, a sensitivity of 8 % /T, and a FoM of 569-MHz/A2mW, significantly higher than current state-of-the-art. Further enhancements were proposed to CH09 as a new chip CH100, aiming for accuracy levels prerequisite for a real-time power electronic application. The TIA was optimized for a wider bandwidth of 26.7 MHz with nearly 30% reduction of the integrated input referred noise of 26.69 nArms at the probe-AFE interface in the frequency band of DC-30 MHz, and a 10% improvement in the dynamic range. The expected input range is 5-A. The chip incorporates a dual sensing chain for differential sensing to overcome common mode interferences. A novel offset cancellation technique is proposed that would require switching of polarity of bias currents. Thermal gain drift was improved by a factor of 8 and will be digitally calibrated utilizing a new built-in temperature sensor with a post calibration measurement accuracy greater than 1%. The estimated power consumption of the entire system is 55.6 mW. Both prototypes have been implemented through a 90-nm microelectronic process from STMicroelectronics and occupy a silicon area of 2.4 mm2.

Vascular access in patients with peripheral arterial disease undergoing TAVI: the hostile registry

BACKGROUND The optimal access route in patients with severe peripheral artery disease (PAD) undergoing TAVI remains undetermined. OBJECTIVE To compare clinical outcomes with transfemoral access (TFA), transthoracic access (TTA), and non-thoracic alternative access (TAA) in TAVI patients with severe PAD. METHODS Patients with PAD and hostile femoral access (TFA impossible, or possible only after percutaneous treatment) undergoing TAVI at 28 international centers were included in this registry. The primary endpoint was the propensity-adjusted risk of 30-day major adverse events (MAE) defined as the composite of all-cause mortality, stroke/transitory ischemic attack (TIA) or main access site-related VARC 3 major vascular complications. Outcomes were also stratified according to the severity of PAD using a novel risk score (Hostile score). RESULTS Among the 1,707 patients included in the registry, 518 (30.3%) underwent TAVI with TFA after percutaneous treatment, 642 (37.6%) with TTA, and 547 (32.0%) with TAA (mostly transaxillary). Compared with TTA, both TFA (adjusted HR=0.58, 95%CI 0.45-0.75) and TAA (adjusted HR=0.60, 95%CI 0.47-0.78) were associated with lower 30-day rates of MAE, driven by fewer access site-related complications. Composite risks at 1 year were also lower with TFA and TAA compared with TTA. TFA compared with TAA was associated with lower 1-year risks of stroke/TIA (adjusted HR=0.49, 95%CI 0.24-0.98), a finding confined to patients with low Hostile scores (Pinteraction=0.049). CONCLUSIONS Among patients with PAD undergoing TAVI, both TFA and TAA were associated with lower 30-day and 1-year rates of MAE compared with TTA, but 1-year stroke/TIA rates were higher with TAA compared with TFA.

QUALIFICAÇÃO DOS PROFISSIONAIS DA UBSF SÃO BENEDITO PARA A IMPLANTAÇÃO DA POLÍTICA DE SAÚDE INTEGRAL DA POPULAÇÃO NEGRA

O presente projeto teve como proposta a qualificação dos trabalhadores da Unidade de Saúde São Benedito, com o objetivo de implantar ações da Política Nacional de Saúde Integral da População Negra na Comunidade Quilombola “Tia Eva”, utilizando recursos de educação permanente que permitiu a equipe pensar, refletir e construir conhecimento para mudança no processo de trabalho. Após a realização da oficina 84% dos participantes passaram a conhecer a PNSIPN. Em relação às doenças que acometem a população negra e seus fatores de risco, 83% relataram ser capazes de reconhecê-las, no entanto, percebe-se que ainda há dificuldades de correlacionar as patologias e identificar os fatores de risco. Quanto à discriminação étnica/racial e social, o resultado apontou que quase todos os profissionais acreditam existir a discriminação étnica – racial e social da população negra e 89% dos participantes acreditam que as iniquidades e desigualdades em saúde são relevantes para uma boa saúde.Diante do cenário apresentado a equipe identificou a necessidade dedar continuidade às discussões sobre o racismo, sobre a saúde da população negra e suas especificidades, propondo ações de promoção, educação em saúde com a comunidade negra, envolvendo o controle social.

Diabetes Mellitus: estratégia para melhor abordagem ao paciente

Sabe-se que o diabetes representa uma síndrome clínica caracterizada por hiperglicemia crônica, com distúrbios no metabolismo de carboidratos, lipídeos e proteínas, apresentando alta morbimortalidade, sobretudo quando não acompanhada adequadamente.Na população atendida em nossa área de abrangência é condição que merece destaque, tendo em vista que os registros da equipe apontam para um subdiagnóstico da doença, considerando a epidemiologia nacional. Os registros com relação ao estado de compensação dos pacientes também são bastante precários e o mais importante, o acompanhamento dos mesmos não segue qualquer protocolo, sendo feito praticamente por demanda espontânea. Este trabalho objetivou elaborar um plano de intervenção para melhorar o acompanhamento de pacientes diabéticos, na Estratégia Saúde da Família Tia Lia, em Mendonça e Veredinha, Minas Gerais. Com vistas à fundamentação do Plano fez-se pesquisa bibliográfica na base de dados do SciELO, no acervo da biblioteca virtual do NESCON e nas Diretrizes da Sociedade Brasileira de Diabetes, com os descritores: Diabetes Mellitus, Estado pré-diabético, Complicações do Diabetes, Retinopatia Diabética, Fatores de risco e Continuidade da assistência ao paciente. O projeto de intervenção foi estruturado com base no método Planejamento Estratégico Situacional (PES) e, após posto em prática, espera-se que haja uma melhora na qualidade da assistência aos pacientes diabéticos, baseando-se em um modelo padrão de acompanhamento, com ações programadas e, consequentemente, melhorar os indicadores da doença.