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Aumento do nível de óleo em dietas isoenergéticas para cavalos submetidos a exercício; Increase of oil level in isoenergetic diets of exercising horses

Marqueze, Alessandra; Kessler, Alexandre de Mello; Bernardi, Mari Lourdes
Fonte: Universidade Federal do Rio Grande do Sul Publicador: Universidade Federal do Rio Grande do Sul
Tipo: Artigo de Revista Científica Formato: application/pdf
POR
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O efeito da inclusão de óleo de soja na dieta foi avaliado em 4 cavalos machos castrados, mestiços Quarto de Milha, com idade aproximada de 42 meses e peso médio inicial de 382kg. Os cavalos foram submetidos a exercício de intensidade e duração média e receberam a dieta controle (sem óleo de soja) e a dieta com óleo de soja (4,7% de óleo) duas vezes ao dia, por 3 períodos de 21 dias, num delineamento do tipo Reversão Simples. A ração foi fornecida de modo a proporcionar uma ingestão diária isoprotéica e isoenergética para os dois tratamentos. Foram avaliados os seguintes parâmetros: freqüência cardíaca (FC), freqüência respiratória (FR) e a concentração de glicogênio muscular, antes do exercício e 20 minutos após o término do exercício, e os níveis plasmáticos de glicose e de lactato, antes do exercício e aos 10, 20, 30 e 50 minutos após o exercício O aumento do nível de óleo na dieta não influenciou significativamente (P>0,05) a FC, a FR, os níveis de glicose e de lactato, antes e após o exercício. A concentração de glicogênio muscular foi maior (P<0,025), antes do exercício, para os cavalos que receberam a dieta com óleo de soja. O aumento da concentração de glicogênio em cavalos condicionados a consumir dieta com óleo de soja pode significar um maior suprimento de energia para a atividade muscular...

Estudo experimental da co-injeção de vapor e gases efluentes de combustão na recuperação melhorada de óleo pesado; Experimental study of steam and flue gas co-injection in improved heavy oil recovery

Lucas Soares Monte-Mor
Fonte: Biblioteca Digital da Unicamp Publicador: Biblioteca Digital da Unicamp
Tipo: Dissertação de Mestrado Formato: application/pdf
Publicado em 25/07/2013 PT
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A injeção de vapor produzido na superfície é o método de recuperação avançada de petróleo mais utilizado para produção de óleo pesado no mundo. No entanto, há grandes limitações no uso no método devido a perdas de calor quando os reservatórios são profundos e no caso de campos offshore. Os geradores de fundo de poço ("Downhole steam generators, DHSG") são uma nova tecnologia que abre caminho para a recuperação de óleo pesado de reservatórios profundos, campos offshore e locais extremamente frios. Os DHSGs eliminam a necessidade dos sistemas de distribuição e geração de vapor na superfície como as linhas de escoamento de vapor. A saída de um DHSG entrega uma mistura de vapor e gases efluentes de combustão. No presente trabalho, um estudo experimental na célula linear de injeção foi desenvolvido para compreender melhor como a injeção combinada de vapor e gases efluentes de combustão contribui no processo de recuperação e para a possível redução na quantidade de vapor injetado. O estudo experimental foi realizado num aparato construído e desenvolvido na Unicamp para a injeção contínua de vapor puro ou vapor combinado com outro fluido. Todo o estudo foi realizado em escala de laboratório utilizando óleo proveniente da bacia Potiguar e do Espírito Santo. Nos experimentos...

Extraction of caffeine, chlorogenic acids and lipids from green coffee beans using supercritical carbon dioxide and co-solvents

Azevedo,A. B. A.de; Mazzafera,Paulo; Mohamed,R. S.; Melo,S. A. B. Vieira de; Kieckbusch,T. G.
Fonte: Brazilian Society of Chemical Engineering Publicador: Brazilian Society of Chemical Engineering
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/09/2008 EN
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The paper reports on experimental data on the extraction of caffeine, coffee oil and chlorogenic acids from green coffee beans using pure supercritical CO2 and supercritical CO2 modified with ethanol (5% w/w) and isopropyl alcohol (5% w/w) at 50 and 60ºC and 15.2 24.8 e 35.2 MPa. In this study extraction kinetics were obtained for all assays i.e. samples were collected at several time intervals for each solvent and mixed solvent. When pure CO2 and CO2-ethanol mixed solvent were used, an increase in pressure resulted in an increase in the amount of oil extracted. When CO2 was modified with isopropyl alcohol, the amount of coffee oil extracted also increased with pressure. Caffeine extraction initially increased and subsequently decreased with pressure. Chlorogenic acids were only extracted when isopropyl alcohol was used as a co-solvent. An increase in extraction temperature resulted in a decrease of caffeine and oil extraction (retrograde condensation) when only CO2 was used as solvent. With the use of co-solvent this retrograde behavior was no longer observed and the increase in temperature resulted in the increase in the extracted amounts of caffeine, coffee oil and chlorogenic acids.

Science in support of the Deepwater Horizon response

Lubchenco, Jane; McNutt, Marcia K.; Dreyfus, Gabrielle; Murawski, Steven A.; Kennedy, David M.; Anastas, Paul T.; Chu, Steven; Hunter, Tom
Fonte: National Academy of Sciences Publicador: National Academy of Sciences
Tipo: Artigo de Revista Científica
EN
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This introduction to the Special Feature presents the context for science during the Deepwater Horizon oil spill response, summarizes how scientific knowledge was integrated across disciplines and statutory responsibilities, identifies areas where scientific information was accurate and where it was not, and considers lessons learned and recommendations for future research and response. Scientific information was integrated within and across federal and state agencies, with input from nongovernmental scientists, across a diverse portfolio of needs—stopping the flow of oil, estimating the amount of oil, capturing and recovering the oil, tracking and forecasting surface oil, protecting coastal and oceanic wildlife and habitat, managing fisheries, and protecting the safety of seafood. Disciplines involved included atmospheric, oceanographic, biogeochemical, ecological, health, biological, and chemical sciences, physics, geology, and mechanical and chemical engineering. Platforms ranged from satellites and planes to ships, buoys, gliders, and remotely operated vehicles to laboratories and computer simulations. The unprecedented response effort depended directly on intense and extensive scientific and engineering data, information, and advice. Many valuable lessons were learned that should be applied to future events.

A Colorimetric Method for the Determination of Oil Deposit on Citrus Leaves

McCall, G. L.; Kagy, J. F.
Fonte: Oxford University Press Publicador: Oxford University Press
Tipo: Artigo de Revista Científica Formato: text/html
EN
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The determination of the quantity of petroleum oil deposited on the leaves of a citrus tree by various spray emulsions has been the subject of considerable discussion and research. It is of primary importance to know the amount of oil deposited, in order to correlate the data with the factors of insect toxicity and injury to the tree. When oil sprays are tested to ascertain their respective toxicity to insects, it is very easy to draw erroneous conclusions with regard to differences in effectiveness. In reality, the apparent differences may be due to the fact that under a given set of conditions one spray emulsion will deposit a larger amount of oil than will another. A slight change in the physical or chemical properties of the emulsion may affect the results very markedly (Hensill & Hoskins 1935, Ben-Amotz & Hoskins 1937, Brown & Hoskins 1939). The accurate determination of the oil deposited is therefore of the greatest importance.

Modeling engine oil vaporization and transport of the oil vapor in the piston ring pack on internal combustion engines

Cho, Yeunwoo, 1973-
Fonte: Massachusetts Institute of Technology Publicador: Massachusetts Institute of Technology
Tipo: Tese de Doutorado Formato: 172 p.; 5630126 bytes; 5651392 bytes; application/pdf; application/pdf
ENG
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A model was developed to study engine oil vaporization and oil vapor transport in the piston ring pack of internal combustion engines. With the assumption that the multi-grade oil can be modeled as a compound of several distinct paraffin hydrocarbons, a set of equations governing the oil vapor density variations were derived by applying the mass conservation law to the amount of oil vaporized from the piston and the amount of oil vapor transported within the piston ring pack. The model was applied to a heavy-duty diesel engine. First, the case with the maximum oil supply to all the piston regions was studied and the results showed that, under this condition, the oil consumption from vaporization alone was far greater than the typical oil consumption value measured in the engine. Then, to show the contribution of oil vaporization to oil consumption and the dependence of vaporization on oil supply to different regions, different lubrication conditions for the high temperature regions of the piston were studied. Finally, a liquid oil transport model was integrated with this oil vaporization model in order to investigate the change of oil composition on the crown land with each engine cycle and the contribution of liquid-phase oil and vapor-phase oil to the total oil consumption under a fixed liquid oil supply rate to the crown land.; by Yeunwoo Cho.; Thesis (S.M.)--Massachusetts Institute of Technology...

Performance of drift tubes under high radiation

Shi, Yue, S.B. Massachusetts Institute of Technology
Fonte: Massachusetts Institute of Technology Publicador: Massachusetts Institute of Technology
Tipo: Tese de Doutorado Formato: vii, 67 p.; 3492452 bytes; 3495458 bytes; application/pdf; application/pdf
ENG
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In this thesis, the aging and the rejuvenation of an ATLAS proportional drift tube are described. Firstly, the Diethorn model of gain is tested using pressure and sense-wire voltage measurements. The drift tube was then aged using P10 gas (Ar:CH₄ 90:10) and a small amount of Si oil vapor, with a tube section of radius [approx.] 1 cm being subjected to UV radiation. An aging current of 30[mu]A was maintained and after the accumulation of 21 coulombs on the wire, the tube gain decreased to less than 70%. Subsequently, the tube was rejuvenated by the treatment with Ar:0₂ 99:1 gas, at reverse wire potential and an reverse "rejuvenation" current of 30[mu]A. Rejuvenation was successful after the accumulation of the equivalent of 3C from this current.; by Yue Shi.; Thesis (S.B.)--Massachusetts Institute of Technology, Dept. of Physics, 2005.; Includes bibliographical references (p. 63-67).

Caucasus Transport Corridor for Oil and Oil Products

World Bank
Fonte: Washington, DC Publicador: Washington, DC
EN_US
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This study evaluates the potential demand for oil and oil products transport via the existing rail corridor in the Caucasus, taking into consideration the competition from alternative routes. It identifies potential bottlenecks that would prevent the potential traffic from using the corridor and proposes solutions for the physical and operational improvements to the corridor needed to attract the potential traffic. The report is based on a review of studies of oil production and transport, and interviews with oil producers, transportation intermediaries, railways, and ports in the region. The report begins with a discussion of the outlook for Caspian oil production and transport options for oil. Next, it discusses the physical and commercial constraints on the Caucasus rail corridor. It ends with a market analysis, strategies for attracting business, and significant actions needed to address the problems outlined previously in the report.

The Vulnerability of African Countries to Oil Price Shocks : Major Factors and Policy Options, The Case of Oil Importing Countries

Bacon, Robert; Mattar, Adib
Fonte: World Bank, Washington, DC Publicador: World Bank, Washington, DC
EN_US
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Apart from a few oil exporters, Sub-Saharan Africa consists of a large number of low-income countries, many of which are highly dependent on oil imports as a source of primary energy. The purpose of this study is to provide information on a number of aspects of energy and oil use in these countries, with a view to highlighting the vulnerabilities of the different countries against sustained or even increasing oil prices, and explore some of the policy implications. The topics investigated are: 1) How vulnerable is each country at present to a sustained oil price rise measured in terms of the ratio of net oil imports to gross domestic product (GDP), and in terms of its ability to pay as indexed by the ratio of net external debt to GDP? 2) What are the energy and oil intensities of the economies and what are the recent trends (measured by the ratio of energy use to GDP)? Can countries expect that energy and oil intensity will rise or fall as the level of development improves? 3) What is the oil fuel dependence of the economy...

Experiences with Oil Funds : Institutional and Financial Aspects

Bacon, Robert; Tordo, Silvana
Fonte: World Bank, Washington, DC Publicador: World Bank, Washington, DC
EN_US
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This study brings together detailed information on the creation, operation, and financial performance of 12 oil funds and 3 other resource funds. The report looks at various funds in Alaska, Alberta, Azerbaijan, Norway, Chad, Sao Tome Principe, Timor, Chile, Nauru, Papua New Guinea, Kazakhstan, Kuwait, Oman, Venezuela, and Russia. The purpose of the study is to provide comparative information on the backgrounds of the creation of these funds, the legislation used to do so, the details of the organization and management of the funds, and of their financial performance. The report opens with a brief review of the reasons for establishing an oil fund and the principal issues involved. The report then provides detailed coverage of four oil funds where there is substantial public information about the operation and performance of the funds. The final chapter provides some comparative material on the different funds and explores the construction of a set of indicators for good practice in the design of the funds. The appendixes contain the legislation which created the governing funds.

WAG displacements of oil-condensates accounting for hydrocarbon ganglia

Bedrikovetski, P.
Fonte: Kluwer Academic Publ Publicador: Kluwer Academic Publ
Tipo: Artigo de Revista Científica
Publicado em //2003 EN
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During two-phase flow in porous media, non-wetting phase is present simultaneously in states of mobile connected continuum and of trapped isolated ganglia. Mass exchange between these two parts of non-wetting phase is going on by dissolution and diffusion of component in the wetting phase, so, compositions of non-wetting phase in both parts are different. Nevertheless, the traditional mathematical model for two-phase multicomponent transport in porous media assumes the homogeneous distribution of each component in the overall non-wetting phase. New governing equations honouring ganglia of non-wetting phase are derived. They are successfully verified by a number of laboratory tests. Analytical model is developed for miscible water-alternate-gas (WAG) displacement of oil-condensates. The modelling shows that the significant amount of oil-condensate is left in porous media after miscible WAG, while the traditional model predicts that the miscible displacement results in the total sweep.; Bedrikovetski, P. G.; The original publication can be found at www.springerlink.com © Springer

Key Drivers of PPPs in Electricity Generation in Developing Countries : Cross-Country Evidence of Switching between PPP Investment in Fossil Fuel and Renewable-Based Generation

Vagliasindi, Maria
Fonte: World Bank, Washington, DC Publicador: World Bank, Washington, DC
Tipo: Publications & Research :: Policy Research Working Paper; Publications & Research
ENGLISH; EN_US
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This paper presents new global evidence on the key determinants of public-private partnership investment in electricity generated by fossil fuels and renewable energy based on a panel data analysis for 105 developing countries over a period of 16 years from 1993 to 2008. It aims to identify the key factors affecting private investors' decision to enter electricity generation, through probit analysis, and the amount of investment sunk in this market segment, based on Heckman's sample selection analysis. The paper shows some evidence of switching from investment in fossil fuels to investment in hydro and renewables and within fossil fuels from oil to natural gas. An interesting result of the econometric analysis is that the likelihood of switching toward renewable investment is driven by long-run environmental factors, such as the increases in the price of oil and the introduction of the Kyoto protocol. Another interesting result is that sector governance support schemes, provided by feed-in tariffs, affect only the entry in renewable based electricity generation and have no impact in reducing the amount of investment in fossil fuel based generation. Economy-wide governance factors...

Vulnerability to Oil Price Increases : A Decomposition Analysis of 161 Countries

Bacon, Robert; Kojima, Masami
Fonte: World Bank, Washington, DC Publicador: World Bank, Washington, DC
Tipo: Publications & Research :: Working Paper; Publications & Research
ENGLISH; EN_US
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This paper examines the levels of and changes in vulnerability to oil price increases between 1996 and 2006 in 161 countries for which data are available. Vulnerability defined here as the ratio of the value of net oil imports to gross domestic product (GDP) rises if oil consumption increases and oil production decreases per unit of GDP. By comparing the level of vulnerability of different economies at a point in time, those that are particularly vulnerable to oil price increases can be highlighted. This enables consideration of the factors (variables) that help determine the magnitude of vulnerability. Over time economies change in ways that may make them more vulnerable to oil price increases or less so, and the change in vulnerability will be related to changes in the underlying variables. The analysis this paper uses is a starting point for linking these factors. The study also examined changes in vulnerability by subdividing the period under review into two sub-periods, 1996-2001 and 2001-6. The oil price increase during the first sub-period was small...

Planning for Higher Oil Prices : Power Sector Impact in Latin America and the Caribbean

Yépez-García, Rigoberto Ariel; San Vicente Portes, Luis; García, Luis Enrique
Fonte: World Bank, Washington, DC Publicador: World Bank, Washington, DC
Tipo: Economic & Sector Work :: Energy Study
ENGLISH; EN_US
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A scenario with higher oil prices has important implications for diverting from oil-based technologies to renewables, as well as gas, coal, and nuclear alternatives. By 2030, energy demand in Latin America and the Caribbean (LAC) is expected to double from 2008 levels. A key issue is deciding on the most appropriate mix of fuels for power generation, given the various prices of energy sources and technologies, as well as availability of renewable energy. The study's broad aim is to evaluate the impact of higher oil prices on the cost of generating electricity in countries of the LAC region so that better-informed energy policy planners can buffer future adverse effects. The study defines high oil prices as those above United States (U.S.) $100 per barrel. This price is considered a reasonable starting point for discussion given the recent range in oil prices, which averaged $95 a barrel in 2011. A price of $150 per barrel is defined as considerably high yet plausible given historical and current price levels...

Fracionamento de oleo de peixe com dioxido de carbono supercritico; Fracionamento of oil of fish with supercritical carbon dioxide

Ana Paula Antunes Correa
Fonte: Biblioteca Digital da Unicamp Publicador: Biblioteca Digital da Unicamp
Tipo: Dissertação de Mestrado Formato: application/pdf
Publicado em 09/09/2003 PT
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Os ácidos graxos polinsaturados ômega-3 (EPA, DHA) são compostos com propriedades terapêuticas no tratamento e prevenção de doenças coronárias, hipertensão, arteriosclerose e artrite, além de serem essenciais para o desenvolvimento e manutenção das funções do sistema nervoso central. Os óleos de peixes de origem marinha são as fontes mais ricas em ômega-3 e por isso têm sido usados com freqüência para a obtenção de concentrados destes ácidos graxos. A deficiência de ômega-3 na dieta da população causada pela baixa ingestão destes ácidos graxos, através do consumo de peixes, toma interessante o enriquecimento de alimentos mais populares como a margarina, pães e produtos lácteos com esses ácidos graxos. A extração com fluido supercrítico é um processo de separação relativamente novo que traz vantagens em relação às técnicas convencionais. Para alimentos, o dióxido de carbono tem sido o solvente mais empregado, por ser inerte, relativamente barato e não inflamável e por possuir pressão e temperatura crítica moderadas (304,15 K, 7,38 MPa), evitando problemas de degradação térmica. Neste trabalho, estudou se o fracionamento com dióxido de carbono supercrítico do óleo de peixe em diferentes condições de temperatura e pressão. Os experimentos foram realizados de 14...

Piston ring pack design effects on production spark ignition engine oil consumption : a simulation analysis

Senzer, Eric B
Fonte: Massachusetts Institute of Technology Publicador: Massachusetts Institute of Technology
Tipo: Tese de Doutorado Formato: 157 p.
ENG
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One of the most significant contributors to an engine's total oil consumption is the piston ring-pack. As a result, optimization of the ring pack is becoming more important for engine manufacturers and lubricant suppliers. This leads to current efforts to control the oil transport and flow through the ring pack. Decreasing the amount of oil needed for proper lubrication while minimizing, frictional losses are the goals of such research. The hope is to fully understand the mechanisms that govern oil's flow, and then control it. Analytical tools and computer simulation models have been created to assist in predicting the performance of a given ring pack. This study intended to be an experimental look at the effects of piston-ring-pack design changes on the steady-state and transient oil consumption of a spark ignition engine. Namely, the effects of a V.-Cut on the 2nd land, a chamfer on the 3rd land, OCR groove drain holes, and the OCR design were to be examined. However, after some minor measurements, the engine experienced a major malfunction that caused it to cease operation. The focus of the study shifted to a more theoretical, computer simulated concentration of the aforementioned design changes. Different speeds -and loads were analyzed along with the notation of some general observations. In the end...

Maximum of oil output of a treadle-powered peanut oil press

Patel, Ravi M. (Ravi Mahendra)
Fonte: Massachusetts Institute of Technology Publicador: Massachusetts Institute of Technology
Tipo: Tese de Doutorado Formato: 35 leaves
ENG
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The manual processing of food products has become a substantial part of the daily routine of a typical household in the developing world. Consumption of oil is an essential part of an individual's diet and thus, the production of oil is an essential activity. In many communities, this oil is obtained by manually pressing it from peanuts. In order to more efficiently and easily express oil from peanuts, a design for a treadle-powered peanut oil press was created. My thesis work will attempt to further increase the amount of oil extracted by optimizing the design of this peanut oil press. The press transfers the motion of the treadle to the horizontal motion of a piston that presses the peanuts via a rotating cam. The focus of this thesis will be optimizing the design of the cam with respect to oil yield. The shape of the cam determines the displacement profile of the piston's compression of the peanuts. I will determine the optimal profile by designing and performing experiments on a variety of different displacement profiles and measuring the amount of oil extracted from the pressed peanuts. The results of these experiments will then determine the optimal cam design.; by Ravi M. Patel.; Thesis (S.B.)--Massachusetts Institute of Technology...

Review of flow rate estimates of the Deepwater Horizon oil spill

McNutt, Marcia K.; Camilli, Rich; Crone, Timothy J.; Guthrie, George D.; Hsieh, Paul A.; Ryerson, Thomas B.; Savas, Omer; Shaffer, Frank
Fonte: National Academy of Sciences Publicador: National Academy of Sciences
Tipo: Artigo de Revista Científica
EN
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The unprecedented nature of the Deepwater Horizon oil spill required the application of research methods to estimate the rate at which oil was escaping from the well in the deep sea, its disposition after it entered the ocean, and total reservoir depletion. Here, we review what advances were made in scientific understanding of quantification of flow rates during deep sea oil well blowouts. We assess the degree to which a consensus was reached on the flow rate of the well by comparing in situ observations of the leaking well with a time-dependent flow rate model derived from pressure readings taken after the Macondo well was shut in for the well integrity test. Model simulations also proved valuable for predicting the effect of partial deployment of the blowout preventer rams on flow rate. Taken together, the scientific analyses support flow rates in the range of ∼50,000–70,000 barrels/d, perhaps modestly decreasing over the duration of the oil spill, for a total release of ∼5.0 million barrels of oil, not accounting for BP's collection effort. By quantifying the amount of oil at different locations (wellhead, ocean surface, and atmosphere), we conclude that just over 2 million barrels of oil (after accounting for containment) and all of the released methane remained in the deep sea. By better understanding the fate of the hydrocarbons...

Oil distribution in potato slices during frying

Pedreschi, Franco; Moyano, Pedro; Troncoso, Elizabeth; Cocio, Claudia
Fonte: ELSEVIER SCI LTD Publicador: ELSEVIER SCI LTD
Tipo: Artículo de revista
EN
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The objective of this research was to study the kinetics of oil absorption and distribution in the structure of potato slices during frying, considering the effects of three oil temperatures and a blanching pre-treatment. Either raw or blanched potato slices (Desire´e variety, diameter: 30 mm, thickness: 3.0 mm) were fried at three constant (±1 C) oil temperatures: 120, 150 and 180 C. The blanching pre-treatment was accomplished in hot water at 85 C for 3.5 min. Raw potato slices were used as the control for the experiments. The amount of oil absorbed was quantified during frying at four time intervals. The following fractions of the total oil (TO) content of potato slices were determined: (i) structural oil (STO); (ii) penetrated surface oil (PSO); and (iii) surface oil (SO). PSO constituted the highest fraction of the total oil content and this was the case for the control as well as the blanched slices, confirming that oil absorption in potato chips is mainly a surface phenomenon. Contrary to expectation, the blanched potato chips absorbed more oil than the control chips. The higher the frying temperature, the lower the oil absorbed by chips. Confocal laser scanning microscopy (CLSM) and scanning electron microscopy (SEM) allowed studying the surface topography of potato chips...

A Study of the effect of oil added to Toray driographic ink on toning in the non-image areas of Toray company's negative working driographic plates

El-Yabroudi, Joseph
Fonte: Rochester Instituto de Tecnologia Publicador: Rochester Instituto de Tecnologia
Tipo: Tese de Doutorado
EN_US
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Several studies and investigations have been conducted to test the new Toray plate. The studies revealed that the new plate eliminated many of the problems that used to hinder the progress and development of the driographic plate system. The two major problems with this plate were short run lengths and toning in the non-image areas. This study investigates toning problems in negative working Toray plates. Toning is a term that refers to the non-image areas of the driographic plate that are accepting ink. Previous studies have shown that ink tack and flow do not affect toning in any way. However, printing speed, nip pressure, printing density and ink temperature were found to have some effect on toning. To investigate the effect that different percentages of oil in the ink has on toning in the non-image areas of Toray negative working plates, this study uses five ink samples, each containing a different percentage of oil, and measures with a densitometer the density of toning in the non-image areas. The hypothesis tested in this study states that the amount of toning in the non-image areas of negative Toray plates increases as the amount of oil contained in the ink increases. Upon analyzing the data collected, it was found that when using the special driographic ink no scumming occured. However...