Navegando por Orientadores "DIAS, Carmen Gilda Barroso Tavares"

Agora exibindo 1 - 9 de 9

Acesso aberto (Open Access)
Análise de um vaso de pressão pós-incidente
(Universidade Federal do Pará, 2021-12-13) RODRIGUES, Igor Florentino; DIAS, Carmen Gilda Barroso Tavares; http://lattes.cnpq.br/2113791118142177
Composite materials have numerous applications in the most varied areas of engineering as offshore, oil and gas industry, marine industries, aeronautics, and automaker. Used because they bring high rigidity and specific resistance, due to the advantages of being resistant to corrosion and having structural flexibility. The work is focused on fiberglass composites with epoxy matrix (FG) and no high-density polyethylene (HDPE) a decade after the incident. The approach was based in two stage, first on an investigation that took place on board of a semisubmersible drilling rig that operates offshore with a drilling capacity of 7500 meters in depth and a water depth of 2500 meters. a high pressure line that is connected to CAPV (composite air pressure vessel) that is part of to the high pressure system of the CMC (Crown mounted compensator). In a second stage, was took samples from CAPV to be analyzed, where impact tests (Charpy) were performed according to ASTM D6110-10 standard, flexion tests according to ASTM D790-17 standard, differential scanning calorimetry (DSC) according to ASTM D3418-12 standard, scanning electron microscopy (SEM) and thermogravimetric to have a more detailed study on the composite materials that made up those vessels, which are PEHD and FG with matrix epoxy. Showed the results of the investigation and finish the work with material analyses assays even after 10 years of manufacture and complications during the use of the vessels.
Acesso aberto (Open Access)
Comportamento mecânico e de flamabilidade de compósito de polipropileno reclicado com fibra de coco e hidróxido de alumínio
(Universidade Federal do Pará, 2006-05-02) SILVA, Vera Lúcia Dias da; DIAS, Carmen Gilda Barroso Tavares; http://lattes.cnpq.br/2113791118142177
The plastic recycling has been an interesting possibility to minimize the destiny problem of the plastic residues. The polypropylene (PP) is enters the types polymers of larger consumption, therefore the utilization of this material has been enabling the studies development of great scientific and social relevance. This polymer presents excellent cost-performance relation, besides can be easily conformed and to exibit mechanical properties that turns it useful in several applications. However, this material when being burnt generates products that act as combustible so that, for some uses, flame resistance good is necessary. This can be gotten by flame retardant addition, that has the intention to increase the resistance of this material to the ignition and, at the same time reducing the propagation speed of the flame. The aluminium hydroxide, or simply alumina hydrate, is the flame retardant agent used most in the market, therefore it also acts as smoke suppressant and it does not liberate toxic gases during the burning. However, for such properties, high alumina hydrate concentrations are necessary. This causes deterioration in the physical properties of the materials for not have reinforcing character. The natural fibres own good reinforcement capacity when combined adequately with polymers. Also presenting advantages as low cost, low density, biodegradability and in the combustion does not emanate toxic gases. In this work, mixtures contend alumina hydrate and coco fibres had been incorporated polypropylene with the objective of if finding an properties rocking adequate for use of this composite with characteristics flame resistance and mechanical performance. The composites were molded by hot compression and characterized by IV, DRX, MEV, mechanical and non-flammability tests. Increase in the elasticity modulus of the composites in general was observed, as well as increase in the tenacity resistance of the PP/coco fiber composite regarding pure PP. The results had indicated the efficiency of alumina hydrate as it flame retardant, in all the composites, except PP/F, classifying the materials as V-0 according to international norm UL 94V.
Desconhecido
Confecção de discos de desbaste a partir de AI2O3 e pó de vidro
(Universidade Federal do Pará, 2009) OLIVEIRA, Rosane Felice de; DIAS, Carmen Gilda Barroso Tavares; http://lattes.cnpq.br/2113791118142177
This article describes the development of abrasive and cutting disks made of alumina and waste glass powder to apply in cutting tools. These disk mills are used to micromize rigid post-consumed thermoplastics and let its use in a lot of recycling process, as rotomolding. This cutting disk uses glass powder as a fluxing agent and poly(ethylene terephthalate) post-consumed to give a plastic behavior to the powder, making it easier to fill in the mold. The amounts of glass powder were analyzed from previous studies with different minerals, as diopside and feldspar, since the studies with waste glass powder substituting natural minerals are recent. The development of the disks occurs in two steps. The first one is the homogeneization of the compounds with the calculated amounts. Afterwards it's pressed and taken to the mufla to get the percolation of the resin and its complete degradation up to a temperature of 900oC, pre-sintering and soften the silicates. After getting these green composites, it happens the second and final step, when the disks are sintered to decrease the porosity and improve its strength, followed by a superficial finish and cutting tests.
Desconhecido
Descontaminação de máscaras N95 em hospital público de Belém/PA: apresentação e avaliação de protocolo simplificado
(Universidade Federal do Pará, 2024-11-25) MATTOS, Simone Lopes de; DIAS, Carmen Gilda Barroso Tavares; http://lattes.cnpq.br/2113791118142177
he author presents a protocol for decontamination of N95 filter masks by means of short wave ultraviolet irradiation (UV-C), as well as the results of the microbiological validation testing of the UV-C device and qualitative research on the adherence of professionals from the João de Barros Barreto University Hospital, of the University Hospital Complex of the Federal University of Pará (HUJBB) to the aforementioned protocol. The microbiological tests demonstrated the efficacy of the decontamination protocol, as there was no bacterial growth in culture media inoculated with swabs of masks used in the hospital and decontaminated in the UV-C device, which proved the germicidal efficiency of UV-C irradiation. The results of the qualitative research point to the adherence of nursing professionals to the practice of mask decontamination, recognizing the practicality and contribution of the protocol to biosafety and occupational safety. As part of the same protocol, an alternative packaging for storing masks in the intervals of use of N95 masks is presented, considering their safe reuse. The protocol also has the following advantages: low cost and practicality of use, in addition to contributing to the reduction of infectious waste. Descriptors: Decontamination. Ultraviolet Rays. Radiation Dosimeters. Personal Protective Equipment. Respiratory Protection Devices. biosecurity.he author presents a protocol for decontamination of N95 filter masks by means of short wave ultraviolet irradiation (UV-C), as well as the results of the microbiological validation testing of the UV-C device and qualitative research on the adherence of professionals from the João de Barros Barreto University Hospital, of the University Hospital Complex of the Federal University of Pará (HUJBB) to the aforementioned protocol. The microbiological tests demonstrated the efficacy of the decontamination protocol, as there was no bacterial growth in culture media inoculated with swabs of masks used in the hospital and decontaminated in the UV-C device, which proved the germicidal efficiency of UV-C irradiation. The results of the qualitative research point to the adherence of nursing professionals to the practice of mask decontamination, recognizing the practicality and contribution of the protocol to biosafety and occupational safety. As part of the same protocol, an alternative packaging for storing masks in the intervals of use of N95 masks is presented, considering their safe reuse. The protocol also has the following advantages: low cost and practicality of use, in addition to contributing to the reduction of infectious waste. Descriptors: Decontamination. Ultraviolet Rays. Radiation Dosimeters. Personal Protective Equipment. Respiratory Protection Devices. biosecurity.he author presents a protocol for decontamination of N95 filter masks by means of short wave ultraviolet irradiation (UV-C), as well as the results of the microbiological validation testing of the UV-C device and qualitative research on the adherence of professionals from the João de Barros Barreto University Hospital, of the University Hospital Complex of the Federal University of Pará (HUJBB) to the aforementioned protocol. The microbiological tests demonstrated the efficacy of the decontamination protocol, as there was no bacterial growth in culture media inoculated with swabs of masks used in the hospital and decontaminated in the UV-C device, which proved the germicidal efficiency of UV-C irradiation. The results of the qualitative research point to the adherence of nursing professionals to the practice of mask decontamination, recognizing the practicality and contribution of the protocol to biosafety and occupational safety. As part of the same protocol, an alternative packaging for storing masks in the intervals of use of N95 masks is presented, considering their safe reuse. The protocol also has the following advantages: low cost and practicality of use, in addition to contributing to the reduction of infectious waste. Descriptors: Decontamination. Ultraviolet Rays. Radiation Dosimeters. Personal Protective Equipment. Respiratory Protection Devices. biosecurity.he author presents a protocol for decontamination of N95 filter masks by means of short wave ultraviolet irradiation (UV-C), as well as the results of the microbiological validation testing of the UV-C device and qualitative research on the adherence of professionals from the João de Barros Barreto University Hospital, of the University Hospital Complex of the Federal University of Pará (HUJBB) to the aforementioned protocol. The microbiological tests demonstrated the efficacy of the decontamination protocol, as there was no bacterial growth in culture media inoculated with swabs of masks used in the hospital and decontaminated in the UV-C device, which proved the germicidal efficiency of UV-C irradiation. The results of the qualitative research point to the adherence of nursing professionals to the practice of mask decontamination, recognizing the practicality and contribution of the protocol to biosafety and occupational safety. As part of the same protocol, an alternative packaging for storing masks in the intervals of use of N95 masks is presented, considering their safe reuse. The protocol also has the following advantages: low cost and practicality of use, in addition to contributing to the reduction of infectious waste. Descriptors: Decontamination. Ultraviolet Rays. Radiation Dosimeters. Personal Protective Equipment. Respiratory Protection Devices. biosecurity.he author presents a protocol for decontamination of N95 filter masks by means of short wave ultraviolet irradiation (UV-C), as well as the results of the microbiological validation testing of the UV-C device and qualitative research on the adherence of professionals from the João de Barros Barreto University Hospital, of the University Hospital Complex of the Federal University of Pará (HUJBB) to the aforementioned protocol. The microbiological tests demonstrated the efficacy of the decontamination protocol, as there was no bacterial growth in culture media inoculated with swabs of masks used in the hospital and decontaminated in the UV-C device, which proved the germicidal efficiency of UV-C irradiation. The results of the qualitative research point to the adherence of nursing professionals to the practice of mask decontamination, recognizing the practicality and contribution of the protocol to biosafety and occupational safety. As part of the same protocol, an alternative packaging for storing masks in the intervals of use of N95 masks is presented, considering their safe reuse. The protocol also has the following advantages: low cost and practicality of use, in addition to contributing to the reduction of infectious waste.
Desconhecido
Perfis de polietileno reciclado carregado com fibra de açaí
(Universidade Federal do Pará, 2012-05-19) BRITO, Paulo Roberto de Oliveira; DIAS, Carmen Gilda Barroso Tavares; http://lattes.cnpq.br/2113791118142177
Were obtained porous tubular profiles, polyethylene (PE) and polyethylene/fiber açai (PE/PA) 80/20 extruded from granulated particles of high-density polyethylene packaging recycled post-consumer 600 μm, and this with fiber açaí 300 μm. For parts processing was developed a mono-screw extruder bench, with System Mechanic powered by an electric motor of ½ HP (0.37 kw) controlled by a frequency inverter with cannons, bagels, array and replaceable heating system. To allow a preview of didactic equipment operating conditions so simplified were conducted tests with paraffin in glass ranging from Cannon-if the screw rotation speeds and temperature profile, adjusting mass flow and pressure in the output. For extrusion of profiles theological tests were conducted with porous of PE and PE/FA screw, barrel being selected and aluminum matrix; bagel with step 9 mm and length diameter ratio (L/D) 22, composed of an element mixer and a floating element in the zone of flow control; angle between the axis and thread screw 17 air gap between the screw and barrel 0.15 mm; 1.3 rpm rotation; heating along the cannon 120º C; tubular array with 21 mm internal diameter and Chuck 19 mm outside diameter. PE profiles and PE/FA showed average pore diameter 0.7 and 0.6 mm; specific gravity to water at a point 28º C 0.77 and 0.73; modulus GPa 1.002 and 2.601 and maximum apparent swelling of extruded 100 and 80%.
Acesso aberto (Open Access)
Produção de chapa plástica a partir do endocarpo de murumuru (astrocaryum murumuru mart.) e poliolefinas recicladas.
(Universidade Federal do Pará, 2021-09-23) LIMA, William Arthur dos Santos de; DIAS, Carmen Gilda Barroso Tavares; http://lattes.cnpq.br/2113791118142177
In the Amazon, a huge amount of non-wood lignocellulosic waste is obtained from the production of oils and butters from pressing of seeds and almonds. The economic and productive viability of plastic sheet has the proposal to close the production cycle of murumuru assets (Astrocaryum murumuru Mart), the two largest companies producing murumuru butter in the metropolitan region of Belem generated 410ton of tegument in the biennium (2019/2020), from the extraction of butter for the cosmetic industry. It also seeks to contribute more options for recycling high-density polyethylene (PEAD) and polypropylene (PP) packaging, used in the storage of oils. The objective of this work was achieved through the production process of plastic plates with properties compatible with the plates currently marketed, positive implications for the environment.
Acesso aberto (Open Access)
Projeto, montagem e testes de fonte Cockcroft - Walton para Electrospinning
(Universidade Federal do Pará, 2022-06-06) ARAÚJO FILHO, Paulo Sérgio Alves de; VIEIRA JÚNIOR, Petrônio; http://lattes.cnpq.br/1958791286192330; DIAS, Carmen Gilda Barroso Tavares; http://lattes.cnpq.br/2113791118142177
Electrospinning is a way of spinning using an electric field, the wire formed has a nanometric diameter and is used in biomaterials, pharmaceuticals, electronics, in the area of semiconductors and energy generation. During electrospinning, the solution leaves a starter vessel and reaches a screen through the force of the electric field. The method fits according to the purpose of the experiment. For each objective there are a variety of polymers, solvents, the latter defining the operating ranges for: field strength, voltage and operating distance. A source was designed and assembled using the Cockcroft multiplier. For the design of the circuit, design and simulations were carried out. For validation, electrospinning was performed using the source.
Acesso aberto (Open Access)
Protótipo de um secador de grãos rotativo compacto com sistema fotovoltaico
(Universidade Federal do Pará, 2023-08-06) RODRIGUES, Benedito de Jesus da Silva; DIAS, Carmen Gilda Barroso Tavares; http://lattes.cnpq.br/2113791118142177 País de Nacionalidade Brasil
The industrial bioeconomy of açaí, a fruit native to the Amazon, produces food with antioxidant phenolic compounds and lipids. Fractions of the pulping by-product are used to generate bioenergy and are being researched as biopolymers, filler for making furniture and architectural materials. With this in mind, two rotary grain dryers were designed: the first is a commercial model (capable of drying 14 kg of açaí kernels) and the second is a compact model (capable of drying 1.0 kg of material). Due to the practicality of its use in the laboratory, the compact model was selected for manufacture. This prototype consists of: a micro motor (with adjustable torque and frequency, 40W of electrical power and bivolt 127/220VAC), which drives a rotating drum (measuring 24cm in diameter by 24cm in length) at a rotation speed of 57.6rpm, an air heating system (consisting of: air confinement chamber, thermal heating module and temperature controller). The equipment is autonomous for forestry use, with a photovoltaic electricity generation system (configuration: a 60Ah battery, a 540WP monocrystalline photovoltaic module, a 40A PWM charge regulator and a 1000W DC/AC inverter). In the laboratory experiments, 1 kg of açaí kernels were dried (for a period of two hours and forty-three minutes), after which the following fractions were obtained: 5% fiber, 1% insoluble particulate matter from the mesocarp and 63% endocarp. The compact rotary grain dryer is a versatile technology that could be used in biomaterials research in the future, contributing to the region's sustainability and macro-economy.
Acesso aberto (Open Access)
O Uso de polímeros reciclados na construção civil: uma proposta de habitação sustentável
(Universidade Federal do Pará, 2023-02-01) FERREIRA, Taiza Naiana da Silva; DIAS, Carmen Gilda Barroso Tavares; http://lattes.cnpq.br/2113791118142177
In recent decades, urban development has resulted in the unbalanced production of plastic materials as waste, waste that can be reused as raw material for a new production cycle. This work presents a proposal for sustainable housing with the use of floors, blocks for sealing with thermo acoustic blanket and sustainable tiles. For their preparation, rotational molding and compression molding equipment was assembled. Residues of polymers and natural fibers were used to make these constructive elements. The polymers used for the development of the floor were polystyrene (PS) disposable cups; ecological blocks were modeled and processed from post-consumer polypropylene (PP) and high-density polyethylene (HDPE) packaging; tiles were molded from discarded laminates; the floors became resistant to abrasion due to the presence of babassu fibers. The blocks provided acoustic comfort by including açaí fiber blankets, the walls were assembled using blocks and a commercial product for laying and overlapping. Housing as a model for recycling materials discarded in the environment will be able to generate proper disposal, providing income, increasing the life cycle of these materials, producing ecological products in civil construction and meeting at least four of the Organization's Sustainable Development Goals-SDGs of the United Nations.