Emergência e desenvolvimento de guanxuma (Sida rhombifolia), capim-braquiária (Brachiaria decumbens) e cana-de-açúcar (Saccharum spp.) influenciados por subprodutos da destilação do álcool

Este trabalho objetivou avaliar os efeitos da aplicação de óleo de fúsel, comparativamente a vinhaça e flegmaça, sobre o desenvolvimento e a composição química de plantas de guanxuma (Sida rhombifolia), capim-braquiária (Brachiaria decumbens) e cana-de-açúcar (variedade RB72454), cultivadas simultaneamente em casa de vegetação. As concentrações de 12,5; 25,0; 50,0; e 100,0% (v/v) de cada subproduto e a testemunha (água) foram aplicadas (numa taxa equivalente a 150 m³ ha-1) no solo dos vasos (22 L), contendo uma planta de cana-de-açúcar (13 cm de altura) e 100 sementes de cada planta daninha. O delineamento foi o inteiramente casualizado, com 13 tratamentos e 4 repetições, em esquema fatorial 3 x 4 (três tipos de resíduos e quatro concentrações), e uma testemunha adicional com água. O óleo de fúsel inibiu a emergência de Sida rhombifolia e Brachiaria decumbens e matou a cana-de-açúcar. A vinhaça e a flegmaça prejudicaram a emergência e o desenvolvimento de B. decumbens, bem como o de S. rhombifolia, mas não o da cana-de-açúcar.

Um Estudo de Politicas e Práticas do uso do GNV no transporte público urbano do Brasil

The use of Natural Gas Vehicle has had a fast increase lately. However, in order to have a continuous success this Program needs to develop converting devices of Otto-cycle engines, gasoline or alcohol, to the use of NGV (Natural Gas Vehicle) that presents low cost, maintaining the same original development of the vehicle and low level of emissions, considering the PROCONVE rules. Due to the need to diversify the matrix in order to avoid energetic dependence and due to strict pollution control, it has increased in the Brazilian market the number of vehicles converted to the use of NGV. The recent regulation of the PROCONVE, determining that the converted engines with kits should be submitted to emission testing, comes to reinforce the necessity of the proposed development. Therefore, if we can obtain kits with the characteristics already described, we can reach a major trust in the market and obtain an increase acceptance of the vehicle conversion for NGV. The use of natural gas as vehicle fuel presents several advantages in relation to liquid fuels. It is a vehicle fuel with fewer indexes of emissions when compared to diesel; their combustion gases are less harmful, with a major level of safety than liquid fuels and the market price is quite competitive. The preoccupation that emerges, and the motivation of this project, is to know which are the main justifications for such technology, well accepted in other countries, with a low index or emission, with a high level of safety, where its maintenance becomes low, reminding that for this it is necessary that this technology has to be used properly, and once available in the market will not motivate interest in the urban transportation companies in Brazil, in research centers in general. Therefore this project exists to show the society in a general way the current vision of the main governmental factors, of the national research centers and of the private companies concerning the use of natural gas vehicles in urban transport vehicles, in order to give a major reliability to the population as well as to motivate national market competitiveness with a low cost and reliable product and to enrich the national technology

Consumo de combustível na operação de subsolagem realizada antes e depois de diferentes sistemas de preparo periódico do solo

A subsolagem tem aumentado nos últimos anos de forma indiscriminada, faltando estudos que norteiem os melhores procedimentos para que novos problemas não sejam acrescentados devido a subsolagens inadequadas ou mesmo em solos onde a operação é desnecessária, e principalmente buscar redução no consumo de combustível. Dessa forma, este trabalho teve o objetivo de avaliar o consumo de combustível na operação de subsolagem efetuada antes e depois de diferentes sistemas de preparo periódico do solo, classificado como Nitossolo Vermelho distroférrico. Os preparos foram realizados com arado de discos, arado de discos mais uma gradagem de nivelamento, grade pesada, grade pesada mais gradagem de nivelamento e escarificador. A realização da subsolagem depois dos sistemas de preparo periódico requereu 15% menos de potência na barra de tração. A subsolagem depois dos diferentes sistemas de preparo economizou 16,5% de combustível por área. O deslizamento das rodas motrizes e a velocidade média operacional obtiveram melhor desempenho quando se realizou a subsolagem depois do preparo do solo.

Consumo de combustível em diferentes sistemas de preparo periódico realizados antes e depois da operação de subsolagem

Foi estudado o consumo de combustível de diferentes sistemas de preparo periódico, realizados antes e depois da operação de subsolagem num solo classificado como Nitossolo Vermelho Distroférrico. As operações de preparo foram: a) 1 aração com arado de discos; b) 1 aração com arado de discos e 1 gradagem com grade destorroadora-niveladora; c) 1 gradagem com grade aradora; d) 1 gradagem com grade aradora e 1 gradagem com grade destorroadora-niveladora e; e) 1 escarificação com escarificador. O consumo específico (g kWh-1) de combustível para os diferentes sistemas de preparo periódico do solo variou estatisticamente com a condição de subsolagem realizada antes e depois. A escarificação proporcionou menor volume de combustível requerido por hectare (L ha-1) que os demais sistemas de preparo. O preparo do solo depois da subsolagem obteve um maior volume de combustível consumido por área (L ha-1).

Desenvolvimento de nanocompósito (hidroxiapatita/ poliuretano) pela gelação (gelling) de poli ( álcool vinílico) (PVA) para remoção de metais pesados

Removing microcontaminants from effluents is a challenge today, because of its high cost and low efficiency, especially in the treatment of effluents containing heavy metals. An alternative that has emerged is the use of biodegradable nanocomposites, which exhibit good removal and recovery performances, in addition to its low cost. With this in mind, the present study aimed to develop and characterize a nanocomposite based on hydroxyapatite (HAP), polyurethane (PU) and polyvinyl alcohol (PVA) for removing heavy metals. Thus, the research was conducted in several steps: i)- Physico-chemical and microbiological hospital effluent characterization; ii)- Production of hydroxyapatite by aqueous precipitation technique, and their characterization; iii)- Production of the nanocomposite in which the hydroxyapatite was added to the polyurethane prepolymers and then the polyvinyl alcohol/hydroxyapatite film was produced; iv)- Polyvinyl composite without film PU/HAp was also produced in the proportions of 20 and 40% HAp; v)- The composites was characterized by the techniques of XRD, FTIR, SEM / EDS, BET, Zeta Potential and TGA; vi)- The sisal and coconut fibres were washed and dried for comparative tests of adsorption; vii)- Adsorption tests for evaluating the removal of heavy metals (nickel and cadmium). Initial screening adsorption capacity (HAp; PU/HAp - 20 and 40%; PU / HAp / PVA), kinetic studies of adsorption of Cd (II) by HAp; multifactorial design analysis (factorial design) for identifying the most important variables in the adsorption of Cd (II) by composite PU/HAp. Also comparative analysis of adsorption of Cd and Ni by composite PU/HAp were conducted, as well as comparative tests of adsorption of Cd (coconut fibre) and Ni (sisal fibre). It was possible to verify that the composite PU/HAp 40% showed better effectiveness for the removal of Cd (II) and Ni (II), above 80%, equivalent to the lignocellulosic fibre used and HAp produced. As main conclusion, it can be referred that the composite PU/HAp 40% is an effective adsorvent to wastewater treatment for heavy metal removal, with low cost and high efficiency

Desempenho de um veículo flex em bancada dinamométrica de chassi

Flex-fuel vehicles are equipped with Otto Cycle internal combustion engines and have the capability of functioning with more than one type of fuel, mixed at the same tank and burned in the combustion chamber simultaneously. This sort of motorization is a world pattern due to the scarcity of petroleum, the trade of several types of fuels, technology advances and the restriction imposed to gas emissions to the atmosphere. In Brazil, the Flexfuel vehicles are a reality, specially the ones using fuel with 20 to 25% anhydrous alcohol mixed with gasoline and those that use natural gas or original liquid fuel (gasoline or hydrated ethanol). The Brazilian model Fiat Siena, the object of this present scientific investigation, is equipped with a unique electronic central capable of managing the liquid or gaseous fuels. The purpose of this research was to perform a comparative analysis in terms of performance (in terms of both potency and consumption) of a tetra-fuel vehicle - using a chassis dynamometer, operating with different fuels: common gasoline, premium gasoline, Podium gasoline, ethanol or natural gas. It became necessary to develop a bench of tests and trials procedures, as well as to know the functioning of the electronic management of the vehicle under analysis. The experiments were performed at the automotive laboratory in CTGAS-ER (Center of Gas Technologies and Renewable energies) at the light of Brazilian standard ABNT, NBR 7024: Light on-road vehicles - measurement of fuel consumption. The essay results on specific fuel consumption using common gasoline, premium gasoline and Podium gasoline have shown similar results, both for urban and road driving cycles

Análise das emissões atmosféricas por veículos automotores em Natal-RN

The fast urban occupation of Brazil, mainly from the last decade of 50, a sensible degradation of the quality of the air generated mainly for the activities was verified human beings associates to industrialization. From the past years, the situation has gotten worst in function of the increment of the fleet of vehicles in circulation in the great cities. Being these, in the city of Natal-RN, the ones that offer the biggest contributions to the atmospheric pollution. For atmospheric air to be a finite natural resources, indispensable and essential to the maintenance of the life in the land, is necessary to the implementation of action to improve its quality and to protect the health of the population. With the objective to study relative aspects to the characteristics of vehicles in use, the present study it searchs to analyze the levels of emissions of gases generated for vehicles converted bi-fuels into the modalities: natural gas (GNV), gasoline and alcohol, inspected for ends of register and together licensing to the State Department of Transit. One used the data gotten from inspections carried through for the company System Specialized in Inspection To propagate, in the city of the Natal-RN, capital of the State of Rio Grande do Norte, between 14 of November of 2003 and 30 of December of 2004. The analyzed parameters are established in the resolution nº 07/93 CONAMA. Of a total of 1.517 inspected vehicles, a average of 15,2% of failed was gotten, or either, that they emit levels of pollution above of the limits established for the legislation, below of the national average that is of 20,0%. The analysis of the data discloses that 7.3% of the fleet are converted the GNV; the growth of vehicles converted the GNV into the city is gradual, with a average of increment in last the 4 years of 23,3%; it has a vehicle predominance that has as combustible original to the gasoline (88,2%); the inspected fleet has average age of 8 years of use, considered young for the Brazilian standards, except for the moved one to the alcohol (average of use of 15 years). Moreover, the type of fuel is not the main parameter to define the indices of emissions; the age of the fleet is the parameter most important when emission is analyzed to propagate; the gas that more generates failed in the inspections is the corrected carbon monoxide; the vehicles generate higher indices of emissions in idling for all the fuels; the presence of the catalyser was not reflected, as it expected, in the reduction of emissions of gases toxic, however when analyzed according to year of manufacture, it was observed that for the vehicles manufactured between 1997 and 2004, reduction of 46,0% in the failed of the vehicles equipped with catalyser was gotten. In conclusion, the fleet of the studied sample, in average terms, takes care of to the requirements of Resolution CONAMA nº 07/93. The results gotten for the present study can subsidize action of public administrations that aim at to the improvement and the maintenance of the quality of air in the city of Natal-RN, as, for example, to implant a net of monitoramento of the quality of air

Síntese citrato-hidrotermal e caracterização eletroquímica de LSCF para aplicação como catodo em célula a combustível de temperatura intermediária

The lanthanum strontium cobalt iron oxide (La1-xSrxCo1-yFeyO3 LSCF) is the most commonly used material for application as cathode in Solid Oxide Fuel Cells (SOFCs), mainly due to their high mixed ionic electronic conductivity between 600 and 800ºC. In this study, LSCF powders with different compositions were synthesized via a combination between citrate and hydrothermal methods. As-prepared powders were calcined from 700 to 900°C and then characterized by X-ray fluorescence, X-ray diffraction, thermal analyses, particle size analyses, nitrogen adsorption (BET) and scanning electronic microscopy. Films of composition La0,6Sr0,4Co0,2Fe0,8O3 (LSCF6428), powders calcined at 900°C, were screen-printed on gadolinium doped ceria (CGO) substrates and sintered between 1150 and 1200°C. The effects of level of sintering on the microstructure and electrochemical performance of electrodes were evaluated by scanning electronic microscopy and impedance spectroscopy. Area specific resistance (ASR) exhibited strong relation with the microstructure of the electrodes. The best electrochemical performance (0.18 ohm.cm2 at 800°C) was obtained for the cathode sintered at 1200°C for 2 h. The electrochemical activity can be further improved through surface activation by impregnation with PrOx, in this case the electrode area specific resistance decreases to values as low as 0.12 ohm.cm2 (800°C), 0.17 ohm.cm2 (750°C) and 0.31 ohm.cm2 (700°C). The results indicate that the citrate-hydrothermal method is suitable for the attainment of LSCF particulates with potential application as cathode component in intermediate temperature solid oxide fuel cells (IT-SOFCs)

Avaliação da eficiência de catalisadores comerciais na obtenção de biodiesel de algodão (Gossipium hisutum L.)

The increasing demand for energy and the environment consequences derived from the use of fossil energy, beyond the future scarcity of the oil that currently is the main power plant of the world, it stimulated the research around the production of biodiesel. In this work the synthesis of biodiesel of cotton in the methyl route was carried through, for had been in such a way used catalyst commercial homogeneous, Na-Methylat and the K-Methylat, aiming to the evaluation of the efficiency of them. An experimental planning 23 was elaborated aiming to evaluate the influence of the variable (molar reason oil/alcohol, % of catalyst and temperature) in the process as well as indicating the excellent point of operation in each case. The biodiesel was analyzed by gaseous chromatography, indicating a conversion of 96,79% when used Na-Methylat® as catalytic, and 95,65% when the K-Methylat® was used. Optimum result found with regard to the conversion was obtained at the following conditions: molar reason oil/alcohol (1:8), temperature of 40°C and 1% of catalyst Na-Methylat, reaching a 96,79% conversion, being, therefore, above of the established for the European norm (96.5%). The analysis of regression showed that the only significant effect for a confidence level of 95%, was of the changeable temperature. The variance analysis evidenced that the considered model is fitted quite to the experimental response, being statistically significant; however it does not serve inside for make forecasts of the intervals established for each variable. The best samples were analyzed by infra-red (IR) that identified the strong bands of axial deformation C=O of methylic ester, characterized through analyses physicochemical that had indicated conformity with the norms of the ANP, that with the thermal and rheological analyses had together evidenced that biodiesel can be used as combustible alternative in substitution to diesel

Estudo do equilíbrio líquido-vapor do sistema água+etanol+líquido iônico visando a separação do álcool anidro

Anhydrous ethanol is used in chemical, pharmaceutical and fuel industries. However, current processes for obtaining it involve high cost, high energy demand and use of toxic and pollutant solvents. This problem occurs due to the formation of an azeotropic mixture of ethanol + water, which does not allow the complete separation by conventional methods such as simple distillation. As an alternative to currently used processes, this study proposes the use of ionic liquids as solvents in extractive distillation. These are organic salts which are liquids at low temperatures (under 373,15 K). They exhibit characteristics such as low volatility (almost zero/ low vapor ), thermal stability and low corrosiveness, which make them interesting for applications such as catalysts and as entrainers. In this work, experimental data for the vapor pressure of pure ethanol and water in the pressure range of 20 to 101 kPa were obtained as well as for vapor-liquid equilibrium (VLE) of the system ethanol + water at atmospheric pressure; and equilibrium data of ethanol + water + 2-HDEAA (2- hydroxydiethanolamine acetate) at strategic points in the diagram. The device used for these experiments was the Fischer ebulliometer, together with density measurements to determine phase compositions. The experimental data were consistent with literature data and presented thermodynamic consistency, thus the methodology was properly validated. The results were favorable, with the increase of ethanol concentration in the vapor phase, but the increase was not shown to be pronounced. The predictive model COSMO-SAC (COnductor-like Screening MOdels Segment Activity Coefficient) proposed by Lin & Sandler (2002) was studied for calculations to predict vapor-liquid equilibrium of systems ethanol + water + ionic liquids at atmospheric pressure. This is an alternative for predicting phase equilibrium, especially for substances of recent interest, such as ionic liquids. This is so because no experimental data nor any parameters of functional groups (as in the UNIFAC method) are needed

Formulação de novos combustíveis base diesel: avaliação de desempenho e emissões

The industry, over the years, has been working to improve the efficiency of diesel engines. More recently, it was observed the need to reduce pollutant emissions to conform to the stringent environmental regulations. This has attached a great interest to develop researches in order to replace the petroleum-based fuels by several types of less polluting fuels, such as blends of diesel oil with vegetable oil esters and diesel fuel with vegetable oils and alcohol, emulsions, and also microemulsions. The main objective of this work was the development of microemulsion systems using nonionic surfactants that belong to the Nonylphenols ethoxylated group and Lauric ethoxylated alcohol group, ethanol/diesel blends, and diesel/biodiesel blends for use in diesel engines. First, in order to select the microemulsion systems, ternary phase diagrams of the used blends were obtained. The systems were composed by: nonionic surfactants, water as polar phase, and diesel fuel or diesel/biodiesel blends as apolar phase. The microemulsion systems and blends, which represent the studied fuels, were characterized by density, viscosity, cetane number and flash point. It was also evaluated the effect of temperature in the stability of microemulsion systems, the performance of the engine, and the emissions of carbon monoxide, nitrogen oxides, unburned hydrocarbons, and smoke for all studied blends. Tests of specific fuel consumption as a function of engine power were accomplished in a cycle diesel engine on a dynamometer bench and the emissions were evaluated using a GreenLine 8000 analyzer. The obtained results showed a slight increase in fuel consumption when microemulsion systems and diesel/biodiesel blends were burned, but it was observed a reduction in the emission of nitrogen oxides, unburned hydrocarbons, smoke index and f sulfur oxides

Administração experimental de esteróide anabólico androgênico e álcool causa alterações histológicas e morfométricas nos ovários e útero de ratas adultas

Abusive and indiscriminate use of androgenic anabolic steroid is an usual practice among youth and adults of both sex. Usually these substances were utilized simultaneously with others drugs, licit or not, that causes damage to health. The purpose of study was to evaluate the influence of experimental administration of nandrolone decanoate steroid (ND), associated or not to alcohol, in the ovaries and uterus of adult rats. Females with regular estrous cycle (n = 20), were distributed in the groups: a) control (physiological solution); b) ND (7.5 mg/kg BW; intraperitoneal); c) alcohol (0.2 mL/100g BW; oral); d) ND + AL. The teatments were realized by single dose per week, during twelve consecutive weeks. The ovaries of rats in the groups ND, AL and ND + AL presented intense follicular atresia and decrease in the number of antral follicles and corpora lutea. None treatment did affect ovarian weight, but uterine weight was increase (p<0.05) in the ND + AL group. There were alterations in the uterine histology and morphometry at function of each treatment. Isolated or simultaneous use of anabolic steroid and alcohol promotes ovarian and uterine toxicity in adult female rats.

Aspectos dinâmicos da água versus álcool e acetona por técnicas de congelamento

Water still represents, on its critical properties and phase transitions, a problem of current scientific interest, as a consequence of the countless open questions and of the inadequacy of the existent theoretical models, mainly related to the different solid and liquid phases that this substance possesses. For example, there are 13 known crystalline forms of water, and also amorphous phases. One of them, the amorphous ice of very high density (VHDA), was just recently observed. Other example is the anomalous behavior in the macroscopic density, which presents a maximum at the temperature of 277 K. In order to experimentally investigate the behavior of one of the liquid-solid phase transitions, the anomaly in its density and also the metastability, we used three different cooling techniques and, as comparison systems, we made use of the solvents: acetone and ethyl alcohol. The first studied cooling system employ a Peltier plate, a device recently developed, which makes use of small cubes made up of semiconductors to change heat among two surfaces; the second system is a commercial refrigerator, similar to the residential ones. Finally, the liquid nitrogen technique, which is used to refrigerate the samples in a container, in two ways: a very fast and other one, almost static. In those three systems, three Beckers of aluminum were used (with a volume of 80 ml, each), containing water, alcohol and acetone. They were closed and maintained at atmospheric pressure. Inside of each Becker were installed three thermocouples, disposed along the vertical axis of the Beckers, one close to the inferior surface, other to the medium level and the last one close the superior surface. A system of data acquisition was built via virtual instrumentation using as a central equipment a Data-Acquisition board. The temperature data were collected by the three thermocouples in the three Beckers, simultaneously, in function of freezing time. We will present the behavior of temperature versus freezing time for the three substances. The results show the characterization of the transitions of the liquid

Álcool e comportamento: efeitos na aprendizagem e memória

Excessive alcohol consumption is responsible for many harmful effects on individuals and society. Despite years of research, the mechanisms by which alcohol affects neurological functions and the exact causes of cognitive impairment related to long-term use are unknown. In this sense, this master study proposed to observe how different doses of alcohol affect the addiction response and the learning ability of two fish species: Betta splendens and Danio rerio, the latter a commonly model due to organizational and functional characteristics shared with mammals. For this, different concentrations of ethanol (0%, 0.1%, 0.25%, 1% and 1.5%) were used in acute, chronic and withdrawal treatments. We tested the fish in three experimental protocols: 1) alcohol addiction potential using conditioned place preference, 2) associative conditioning using light as unconditioned stimulus and food as conditioned stimulus and 3) spatial learning using a maze without cues. For the alcohol addiction potential, preference between two different places in a shuttle box was tested before and after alcohol exposure (chronic and acute). In this test, the animals intoxicated by 0.1% did not change behavior, while animals receiving 1% and 1.5% alcohol changed the initial preference to the side where they received alcohol For the associative conditioning, the results show that the groups undergoing low dose (0.1%), both in chronic and withdrawal treatment, learned the task faster than control; groups under 0.25 and 1% alcohol withdrawal learned the task after control; groups chronically intoxicated with these doses did not learn the task. For the spatial learning test, fish submitted to acute and chronic treatments decreased the time to exit the maze; there were significant differences in the animal s performance in a dose-dependent pattern. This difference was not observed for the withdrawal treatment. Given these results, we conclude that the effects of alcohol on learning are dependent on the dosage. Furthermore, low doses of alcohol seem to maximize animal performance on learning tasks and do not alter their seeking behavior, while higher doses induced addition and hinder learning

Álcool e sociabilidade: a farra das adolescentes

The experience as a school psychologist allowed me to notice that expressions like I was like trash in the gang s barbecue , and we chatted away, only the girls, and we all got drunk , are very common in conversations between Elementary and High School students, pointing out to a concerning incidence of alcohol consumption among female adolescents. However, studies about this theme haven t gone deep in the nowadays reality these girls are living in. This study aimed at comprehending the aspects of the relation between girls and alcohol, starting from the point that exaggerated consumption indicates introductory rituals for some groups, making social relations easier and becoming a sociability factor. To give this study some support, a questionnaire was applied to 1028 female teenagers, between 12 and 18 years old, students in private schools in Natal, capital of Rio Grande do Norte. The context chosen for the development of the study - private schools -, arose from the notion that the majority of the data collection carried out about alcohol and other psychotropic drugs aim at public school students. The instrument used was divided in two parts, one that treated about the first contact with alcohol (experimentation), and other that points to the current relation with alcoholic beverages, with 27 closed questions but nevertheless with available space for manifestation like if other; which?, applied collectively in classrooms. The data received a statistic treatment from SPSS and showed that the first contact with alcoholic beverage happens in domestic environment, having parents and friends as companions, very precociously, around 10 years of age, as curiosity. At this moment, Ice drink is the most consumed beverage. The main reason that leads them to drink is to pass the time in parties, and they don t drink alone (93% of students researched), what gives alcohol this recreational and socializing characteristic. They do consider alcohol a kind of drug, but are not afraid of getting addicted. People that drink usually show to be extroverted, they get happier (40,3%) and are not shy at all (29,4%), have attitudes of moral character, like to get involved with unknown boys (18,5%), get numb (9,9%), or get sad (1,9%). They label as vulgar the girls that drink, depending on the amount, and to be stimulated by the boys to drink. The study shows that systematic interventions of the school are necessary, once it is an institution that should care about education and personality traits of children and adolescents, as well as the important role of the psychologist in this context. Besides, it claims the society to get effectively involved with the public policies that already exist