Nitretação em plasma com gaiola catódica: caracterização e avaliação do desempenho da camada nitretada em facas de corte

Nowadays, in the plastic industry are used mills that accomplish the recycling of residues generated in the production of its components. These mills contain cut sheets that suffer accelerated wear, once they are submitted constantly to the tribologic efforts, decreasing its useful life. To reduce this problem, it s used noble steels or takes place superficial treatments. The ionic nitriding process presents some limitations related to the uniformity of the layer in pieces with complex geometry, committing its application in pieces as knives, head offices, engagements, etc. However, the new technique of nitriding in cathodic cage eliminates some problems, as the restrictions rings, inherent to the conventional ionic nitriding. In present work, was studied the use viabilization of steels less noble, as SAE 1020, SAE 4320 and SAE 4340, nitreded by two different techniques, to substitute the AISI 01 steels, usually used in the cut knifes fabrication, seeking to reduce the costs and at the sane time to increase the useful life of these knifes. The steel most viable was the SAE 4340, nitrided in cathodic cage, because it presented uniformity in thickness and in the hardness of the layer, besides of increased 58% in the average its useful life

Atenção ao usuário em um centro de referência HIV/Aids: perspectiva de profissionais e usuários

We study the health care focused on care in an intercessor and dialogical relationship with the User, which involves the construction of therapeutic projects essential to the quality of the treatment of the user in health services, and it is necessary individual and collective actions. It is intended to acknowledge and analyze the perception of social subjects, users and professionals on the treatment given to a user of a Specialized Outpatient Service (Serviço Ambulatorial Especializado SAE) in STD/HIV/AIDS state reference in Natal, RN. The study is structured in a transdisciplinary vision of science and knowledge, theoretical and methodological principles that give meaning to the expression of the institutional features of care and health care reconnecting them to the social context. As a research strategy we seek the expressions of 56 subjects of social research, which agreed to participate in the sample, from a symbolic map of the attention, coupled with the techniques of observation and semi-structured interview. For the analysis of the results, five categories of analysis were established: the meaning of the service, care perception, process of communication and interaction, treatment perception and organization and evaluation of the service. It is argued that the attention and care are developed in a technical health care assistance to the disease, focusing on attention based on treatment, on diagnostic and drug therapy of antiretroviral drugs, reflecting the traditional biomedical paradigm of attention to the disease. This is also the mode of organization of practical actions in daily SAE: the therapy proves to be fragmented in several specialties, vertical and feeds the same model, generating tension and overload for professionals; showing impersonal care focused on structured and informative technology, unrelated to an interactive dialogic. From the speech of the subjects, the SAE is understood as the place of confrontation with the disease, but also enables greater elaboration of the illness by meeting their peers. Living with HIV and AIDS is living with concern, apprehension and fear, but mainly with the stigma, prejudice and exclusion, which require that the disease is kept in secret. There is a movement of forces and power, expressed in the knowledge-power of those who dominate the technical and administrative capabilities, devices that concentrate the maintenance of the medicalization of care, rapid consultations and with little attention, making it difficult to interact with and listen to, combined with structural failures, organizational and inadequate management of the service. We conclude that there are dimensions that are not considered in the internal dynamics of the care service multiple forms, characterized by care conflicting models, marked by individual interventions related to the disease. The subject is not considered together with his speech as technical discourse is imposed and care production based on material technology is observed

Conhecimento dos enfermeiros do Hospital Universitário Onofre Lopes sobre sistematização da assistência de Enfermagem

Nursing as a profession goes in search on quality of their care through new frameworks, trying to break postures of the health care system so fragmented in the care. To change professional practices, it is necessary to build their own knowledge grounded on Nursing Care System. The aim of this study was to analyze the influence of nurses' knowledge on care systematization in nursing in the University Hospital Natal-RN. It is an analytical descriptive study carried out at the Onofre Lopes University Hospital (HUOL), Natal-RN, 2010, the sample was composed of 40 active nurses working in hospitalization units of the hospital, the inclusion criteria were being in the monthly scale sector and agree to participate in the study. The non-participant observation and another interview were used for collecting data, statistical analysis was descriptive and inferential with reliability test, Pearson test, chi-square and Fischer, the variables that correlated were analyzed in a model Multiple logistic , calculating odds ratio. The results were: predominance of female professionals (90%), predominantly in the age range 39-46 years (37.5%), nurses who have the undergraduate degree at the Federal University of Rio Grande do Norte (80%), and who have expertise training as a minimal degree (62.5%). Among the surveyed, the knowledge showed significance with the graduation time (p = 0.018) and time working in HUOL (p = 0.036). The majority of the professionals surveyed do not know which organ is responsible for the SAE legislation (52.5%), aware of the steps needed to build the nursing diagnosis (92.5%), understand the characteristics of nursing planning (90% ). However the same professionals do not perform physical examination in patients (50.0%) did not classify the clinical findings (68.4%), and identify the problems encountered as a classification (13.2%). The planning of nursing care is carried out by verbal order of nurses (82.5%), 41% of the professionals assess only the intervention stage, in other words, the actions taken. Regarding the practical application of nursing records 53% of nurses do not realize records, 30.8% is incomplete, the other held notes (p = 0.003). The nurses know the nursing process (90% of appropriate responses), despite the actions defined by the theory are not applied in practice. Investigators believe the condition of the hospital teacher (22.5%) could positively affect the implementation of the SAE associated with the interest of professionals (20%). Of the respondents, 17.5% accept as truth the lack of facilities to assist the SAE implementation in the hospital. It was concluded that nurses know the theory that underlies the SAE and the nursing process, but do not develop the service know as well, there is need for action to boost the SAE implementation as practice of nurses in the hospital investigated

Avaliação tribológica dos polímeros NBR, PTFE e PTFE gravitado em contato com aço AISI 52100

Low cost seals are made of NBR, Nitrile Butadiene Rubber, a family of unsaturated copolymers that is higher resistant to oils the more content of nitrile have in its composition, although lower its flexibility. In Petroleum Engineering, NBR seal wear can cause fluid leakage and environmental damages, promoting an increasing demand for academic knowledge about polymeric materials candidate to seals submitted to sliding contacts to metal surfaces. This investigation aimed to evaluate tribological responses of a commercial NBR, hardness 73 ± 5 Sh A, polytetrafluoroethylene (PTFE), hardness 60 ± 4 HRE and PTFE with graphite, 68 ± 6 HRE. The testings were performed on a sliding tribometer conceived to explore the tribological performance of stationary polymer plane coupons submitted to rotational cylinder contact surface of steel AISI 52100, 20 ± 1 HRC Hardness, under dry and lubricated (oil SAE 15W40) conditions. After screening testings, the normal load, relative velocity and sliding distance were 3.15 N, 0.8 m/s and 3.2 km, respectively. The temperatures were collected over distances of 3.0±0.5 mm and 750±50 mm far from the contact to evaluate the heating in this referential zone due to contact sliding friction by two thermocouples K type. The polymers were characterized through Thermogravimetric Analysis (TGA), Differential Scanning Calorimetry (DSC) and Dynamic Mechanical Analysis (DMA). The wear mechanisms of the polymer surfaces were analyzed by Scanning Electron Microscopy (SEM) and EDS (Energy-Dispersive X-ray Spectroscopy). NBR referred to the higher values of heating, suggesting higher sliding friction. PTFE and PTFE with graphite showed lower heating, attributed to the delamination mechanism

Surface finishing of flat pieces when submitted to lapping kinematics on abrasive disc dressed under several overlap factors

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Viscosity measurement of Newtonian liquids using the complex reflection coefficient

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Entre o êxito e a frustração com a sistematização da assistência de enfermagem

Pesquisa qualitativa orientada pelos referenciais teórico-metodológicos: Interacionismo Simbólico e Grounded Theory para compreender o processo planejamento-implementação da Sistematização da Assistência de Enfermagem (SAE), segundo dois grupos amostrais: enfermeiros e auxiliares/técnicos de enfermagem de um hospital universitário, e desenvolver uma síntese dos modelos teóricos representativos dessas experiências. A saturação teórica configurou-se mediante a análise da 24ª entrevista não diretiva de 12 enfermeiros e de 12 técnicos de enfermagem, lotados em unidades de internação. da análise emergiram dois modelos teóricos, cuja síntese originou o terceiro, intitulado Entre o êxito e a frustração com a operacionalização da SAE: recursos humanos como componente determinante para a visibilidade do enfermeiro no processo de trabalho. Este modelo desvela o déficit de recursos humanos, impulsionando o enfermeiro a realizar uma SAE ilusória, e perpetuando um processo cíclico de sofrimento, por vivenciar a invisibilidade de sua práxis no processo de trabalho.

Evaluation of grinding fluids in the grinding of a martensitic valve steel with CBN and alumina abrasives

In this paper the performances of different cutting fluids and grinding wheel types were analysed in the grinding of SAE HVN-3 workpieces. The resulting residual stress, wheel wear and roughness were evaluated. The influence of the cutting fluid jet velocity v(j) was also analysed. As a conclusion, the lubrication ability seems to be the governing factor in the cutting fluid performance. The use of CBN wheels can significantly reduce the thermal damage in grinding, leading to compressive residual stresses. The CBN wheel and the cutting oil give an optimum combination for performing this grinding operation.

Optimization of Radial Basis Function neural network employed for prediction of surface roughness in hard turning process using Taguchi's orthogonal arrays

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Time and distance in acceleration of road commercial vehicles

The time and the distance traveled during the acceleration and the velocity retaking are parameters used for the comparison and the project of vehicles. In this paper equations for the calculation of those parameters are presented. Several criteria are presented for the shift gears. It is also verified the occurrence or not of total slip during the acceleration of the vehicle. The theoretical models were implemented in a developed computational system. Such system was applied in a Mercedes-Benz do Brazil sample vehicle, in order to facilitate comparisons between the simulate values and the experimental road tests. Copyright © 1997 Society of Automotive Engineers, Inc.

Fuel consumption of road commercial vehicles in the driving schedule

The fuel consumption is an important factor in the vehicle development due the fact that it has a direct effect on its trade aims. Besides that, it is known that the petrol is a scarce fuel. In this paper it is presented a procedure of fuel consumption calculation for a vehicle traveling in driving schedule. In such calculation it has been taken into account the operational conditions (load, pavement, climbing road, among others) and the building characteristics (map engine, transmission, frontal area, tire, among others) of road vehicles. There has also been an application of the theoretical model developed in a sample Mercedes-Benz do Brasil vehicle which has been compared with the values of experimental tests. Copyright © 1997 Society of Automotive Engineers, Inc.

Advanced ceramics: Evaluation of the mechanism of stock removal and ground surface quality

The aim of this work is to evaluate the mechanism of stock removal and the ground surface quality of advanced ceramics grounded by a plane tangential grinding process with diamond grinding wheels. The analysis of the grinding performance was done regarding the cutting surface wear behavior of the grinding wheel for ceramic workpieces. The discussion about the results emphasized the wear mechanism of the grinding wheel cutting surface and the cutting phenomenology of the grinding process. The grounded surface was evaluated using Scanning Electron Microscopy (SEM). © 1999 Society of Automotive Engineers, Inc.

Unsaturated polyester based composites reinforced with curauá fiber - Preliminary studies

Curauá fiber processing characterization has been performed throughout the different processing steps. Unsaturated polyester has been used as matrix in the production of curauá reinforced composite samples. Compression molding process has been used to prepare the samples. Tensile strength, impact resistance, flexural strength, Young's modulus and elongation at break have been accessed for curauá composites in comparison with fiberglass composites. Mechanical properties were found not to attend the company's internal standards specification. However, the work has shown some alternatives to solve these problems such as the modification of equipment characteristics and resin formulation, the necessity of incorporation of a higher content of fiber and the possibility of using a new type of filler. Copyright © 2000 Society of Automotive Engineers, Inc.

The improvement in grinding of inlet engine valves by the adoption of the most effective cuting fluid type

In this paper is presented an experimental research in which the grinding of seating surfaces of inlet engine valves was improved by the adoption of the most effective cutting fluid type, matching the new requirements of cutting fluid application. Four different types of cutting fluids (straight oil and three different types of soluble oils) were analyzed. As qualitative and quantitative evaluation parameters of the performance of the cutting fluids, the roughness, the grinding wheel wear, the cutting force and the workpiece residual stress were determined. As a conclusion, the straight oil was the cutting fluid that presented the best results in all of the parameters analyzed. Copyright © 2000 Society of Automotive Engineers, Inc.

Considerations in light truck suspension design

The present work aims at to approach considerations of trucks suspension design. The proposal of the work consists of discussing the aspects related to the acting of the suspension and of factors that interact with the system through representative models of the dynamic behaviour of the vehicle ride when operating in total load and/or empty conditions. The importance of this work is to revise some procedures of suspension study in the sense of adapting them to the Brazilian reality, tends in view the importance of the design characterisation and adaptation to the typical roads of Brazil. Copyright © 2000 Society of Automotive Engineers, Inc.