Articles de revues : « Scarico diesel »

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Kovbasenko, Serhii. « Possibilities of enhancing the environmental safety of diesel vehicles using alternative fuels ». Journal of Mechanical Engineering and Transport 16, n^o 2 (17 janvier 2023) : 51–57. http://dx.doi.org/10.31649/2413-4503-2022-16-2-51-57.

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Today, most motor fuels are made from non-renewable sources of petroleum origin. In connection with the environmental problems associated with the use of traditional motor fuels in motor vehicle engines, many countries are implementing strict requirements for the greening of motor vehicles.At the same time, vehicles with diesel engines are quite attractive in terms of consumption of alternative motor fuels. One of the ways to increase the environmental safety of vehicles with diesel engines is the complete or partial replacement of diesel fuel with alternative fuels. In this regard, research and development in the field of energy resource use in road transport has been significantly intensified, and new programs are being developed to expand the use of alternative fuels. The main focus of the researchers on improving environmental safety is the complete or partial replacement of diesel fuel with alternative fuels, which can be of petroleum or non-petroleum origin. Such fuels can be: liquefied petroleum gas, compressed natural gas and associated gases, diesel biofuel, alcohols and ethers, as well as hydrogen, etc.The article examines the problem of alternative types of fuel and the use of new energy sources in the search for more ecologically clean, cheap and less scarce fuel. To solve this problem, it is necessary to perform an analysis and determine the possibilities of increasing the environmental safety of motor vehicles with diesel engines when using different alternative fuels.The analysis carried out in the work showed that the considered fuels are promising with the proper organization of the work process of motor vehicle diesel engines. However, in a number of cases, for example, when using hydrogen, alcohols, it is necessary to significantly change the design of the engine, which requires significant costs. The use of alternative, more environmentally friendly motor fuels, such as compressed natural gas, diesel biofuel of vegetable or animal origin, etc., will allow to significantly expand the fuel base of motor vehicle diesels and does not require a significant change in their design.In further research, an important task is to develop a methodology for evaluating the use of alternative fuels, which will combine a complex of functional and mathematical models to determine the energy efficiency and environmental safety of vehicles with diesel engines when using alternative fuels both in their pure form and in the form of mixed fuels.

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WONG, PAK KIN, CHI MAN VONG, CHUN SHUN CHEUNG et KA IN WONG. « DIESEL ENGINE MODELLING USING EXTREME LEARNING MACHINE UNDER SCARCE AND EXPONENTIAL DATA SETS ». International Journal of Uncertainty, Fuzziness and Knowledge-Based Systems 21, supp02 (31 octobre 2013) : 87–98. http://dx.doi.org/10.1142/s0218488513400187.

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To predict the performance of a diesel engine, current practice relies on the use of black-box identification where numerous experiments must be carried out in order to obtain numerical values for model training. Although many diesel engine models based on artificial neural networks (ANNs) have already been developed, they have many drawbacks such as local minima, user burden on selection of optimal network structure, large training data size and poor generalization performance, making themselves difficult to be put into practice. This paper proposes to use extreme learning machine (ELM), which can overcome most of the aforementioned drawbacks, to model the emission characteristics and the brake-specific fuel consumption of the diesel engine under scarce and exponential sample data sets. The resulting ELM model is compared with those developed using popular ANNs such as radial basis function neural network (RBFNN) and advanced techniques such as support vector machine (SVM) and its variants, namely least squares support vector machine (LS-SVM) and relevance vector machine (RVM). Furthermore, some emission outputs of diesel engines suffer from the problem of exponentiality (i.e., the output y grows up exponentially along input x) that will deteriorate the prediction accuracy. A logarithmic transformation is therefore applied to preprocess and post-process the sample data sets in order to improve the prediction accuracy of the model. Evaluation results show that ELM with the logarithmic transformation is better than SVM, LS-SVM, RVM and RBFNN with/without the logarithmic transformation, regardless the model accuracy and training time.

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Narendranathan, S. K., et K. Sudhagar. « Study on Performance & ; Emission Characteristic of CI Engine Using Biodiesel ». Advanced Materials Research 984-985 (juillet 2014) : 885–92. http://dx.doi.org/10.4028/www.scientific.net/amr.984-985.885.

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Biodiesel are extracted from transesterification process of edible and non-edible oil of vegetable and animal fat. It can be used in the diesel engine either in the form of neat oil or as a mixture of diesel fuel in the form of blend. The properties of oil are compared with the characteristic required for the fuel of internal combustion engine and the properties fuel are compared with conventional diesel fuel. Use of bio-diesel in a conventional diesel engine results in substantial reduction in unburned hydrocarbon (UBHC), carbon monoxide (CO), particulate matters (PM) emission and oxide of nitrogen. The blends of biodiesel with small content in place of petroleum diesel can help in controlling air pollution and easing the pressure on scarce resources without significantly sacrificing engine power and economy.

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Leonardo, Adam, et Semin. « Effect of CNG Engine Conversion on Performance Characteristic : A Review ». IOP Conference Series : Earth and Environmental Science 972, n^o 1 (1 janvier 2022) : 012028. http://dx.doi.org/10.1088/1755-1315/972/1/012028.

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Abstract The world has been experiencing a crisis of energy caused by the deterioration of scarce fossil fuel resources. The usage of fossil fuels, mainly liquid fuels is considered unsustainable due to resource depletion and the accumulation of pollutants. Natural gas has become a promising alternative fuel since it is highly abundant in the world, produces less emission, and gives similar engine performance compared to the existing liquid fuel, diesel, or gasoline. This paper presents various research regarding the engine performance characteristic of CNG. The studies reported that as compared to liquid-based fuel such as diesel oil or gasoline, CNG gives lower brake thermal efficiency (BTE) as compared to diesel fuel. However, the brake-specific fuel consumption (BSFC) of engine fueled with CNG is lower than diesel or gasoline fuel. In terms of exhaust gas temperature, CNG was always produced higher temperatures in comparison to gasoline. The maximum cylinder gas pressure of CNG was reported lower than diesel fuel operation. In general, the power produced by CNG combustion is a little bit lower than diesel fuel, this drawback of CNG fuel can be overcome by adding hydrogen fuel to CNG to increase produced power.

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Ganapathy, Thirunavukkarasu, Parkash Gakkhar et Krishnan Murugesan. « An analytical and experimental study of performance on jatropha biodiesel engine ». Thermal Science 13, n^o 3 (2009) : 69–82. http://dx.doi.org/10.2298/tsci0903069g.

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Biodiesel plays a major role as one of the alternative fuel options in direct injection diesel engines for more than a decade. Though many feed stocks are employed for making biodiesel worldwide, biodiesel derived from domestically available non-edible feed stocks such as Jatropha curcas L. is the most promising alternative engine fuel option especially in developing countries. Since experimental analysis of the engine is pricey as well as more time consuming and laborious, a theoretical thermodynamic model is necessary to analyze the performance characteristics of jatropha biodiesel fueled diesel engine. There were many experimental studies of jatropha biodiesel fueled diesel engine reported in the literature, yet theoretical study of this biodiesel run diesel engine is scarce. This work presents a theoretical thermodynamic study of single cylinder four stroke direct injection diesel engine fueled with biodiesel derived from jatropha oil. The two zone thermodynamic model developed in the present study computes the in-cylinder pressure and temperature histories in addition to various performance parameters. The results of the model are validated with experimental values for a reasonable agreement. The variation of cylinder pressure with crank angle for various models are also compared and presented. The effects of injection timing, relative air fuel ratio and compression ratio on the engine performance characteristics for diesel and jatropha biodiesel fuels are then investigated and presented in the paper.

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Ferreira, A. S., M. C. Nicoletti, J. R. Bertini et R. C. Giordano. « Methodology for inferring kinetic parameters of diesel oil HDS reactions based on scarce experimental data ». Computers & ; Chemical Engineering 48 (janvier 2013) : 58–73. http://dx.doi.org/10.1016/j.compchemeng.2012.08.004.

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Fitri, Noor, Rahmat Riza, Muhammad Kurnia Akbari, Nada Khonitah, Rifaldi Lutfi Fahmi et Is Fatimah. « Identification of Citronella Oil Fractions as Efficient Bio-Additive for Diesel Engine Fuel ». Designs 6, n^o 1 (14 février 2022) : 15. http://dx.doi.org/10.3390/designs6010015.

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Escalation fuel consumption occurs in various regions of the world. However, world oil reserves decline from year to year so that it becomes scarce and causes oil prices to surge up. This problem can be solved by saving fuel consumption. One method of saving fuel is adding bio-additives from citronella oil as a sustainable resource to diesel fuels. Citronellal, citronellol and geraniol are the main components of citronella oil which can be used as fuel additives. This study aimed to evaluate the effect of citronella oil fractions as bio-additives to the performance of diesel engine. The research stages include: extraction of citronella oil, vacuum fractionation of citronella oil, physical chemical characterization of citronella oil and its fractions, formulation of bio-additive -fuel blending, characterization of blending, and evaluation of fuel efficiency. The effect of concentration of the bio-additives was examined towards three diesel fuels; dexlite, pertamina-dex, and biosolar. The results showed two main fractions of citronella oil; citronellal dominant component (FA) and citronellol-geraniol dominant components (FB). The concentration variation of bio-additives was 0.1–0.5%. Fuel consumption efficiency was tested using diesel engine at an engine speed of 2000 rpm and a load increment of 1000, 2000 and 3000 psi with 7 min running time. The fractions represented the different tendencies to enhance the fuel efficiency up to 46%, influenced by the mixture’s concentration. Generally, citronella oil and the fractions showed the potency as bio-additive to diesel fuels.

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Wong, Ka In, Pak Kin Wong, Chun Shun Cheung et Chi Man Vong. « Modelling of diesel engine performance using advanced machine learning methods under scarce and exponential data set ». Applied Soft Computing 13, n^o 11 (novembre 2013) : 4428–41. http://dx.doi.org/10.1016/j.asoc.2013.06.006.

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Fortmeier, K., K. Husmann, A. S. Costa, K. Reetz et S. Heim. « Erprobung des MEC-Tests bei kognitiven Kommunikationsstörungen bei leichten kognitiven Beeinträchtigungen und demenziellen Erkrankungen ». Neurologie & ; Rehabilitation 28, n^o 02 (mai 2022) : 103–8. http://dx.doi.org/10.14624/nr2202009.

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Zusammenfassung Zusammenfassung Bei demenziellen Erkrankungen können die sprachlichkommunikativen Fähigkeiten in variabler Art betroffen sein. Trotzdem fehlen im deutschsprachigen Raum geeignete Standardverfahren zur Diagnostik dieser kognitiven Kommunikationsstörungen. Diese Studie beschäftigt sich mit der Erprobung der Anwendbarkeit des MEC-Tests bei dieser Zielgruppe. 16 Patient*innen mit MCI oder leichtgradiger Demenz wurden mit der CERAD Batterie und mit dem MECTest getestet. Bei 94,1% war der MEC-Test durchführbar. Die Durchführungsdauer von durchschnittlich 72,7 Minuten stand nicht im Zusammenhang mit der CERAD. Die Durchführungsdauer unterschied sich zwischen Patienten mit neurodegenerativer vs. affektiver Genese. Jede/r Patient*in zeigte in durchschnittlich 9 Untertests einen Wert unter dem klinischen Trennwert. Die Leistung im MEC stand in Zusammenhang mit der CERAD. Insgesamt wurden sieben der 14 MEC-Untertests aufgrund von Bodeneffekten oder fehlenden Zusammenhängen mit der CERAD als ungeeignet für die Zielgruppe identifiziert. Zusammenfassend ließ sich eine Auswahl an Subtests des MEC-Testverfahren bei dieser Zielgruppe gut anwenden. Schlüsselwörter: Diagnostik, Demenz, Mild Cognitive Impairment (MCI), Logopädie/Sprachtherapie, kognitive Kommunikationsstörung Abstract Dementia is associated with language and communication deficits. However, standardized diagnostic instruments for the assessment of communication disorders for this population are scarce. Therefore, the present study explores whether the Montreal Evaluation of Communication (MEC) test can be applied to persons with dementia or mild cognitive impairment (MCI). Sixteen patients were tested with the (CERAD) and MEC tests. The MEC test could be completely administered in 94.1%. The average duration of 72.7 minutes was not correlated with the Consortium to Establish a Registry for Alzheimer's Disease CERAD score but differed between neurodegenerative vs. affective etiology. Patients showed language/communication deficits in 9 of the MEC sub-tests. Average performance on the MEC test was correlated with the CERAD score. Seven of the 14 MEC subtests were identified as unsuitable for dementia or MCI because of floor effects in performance or poor association with the CERAD. To conclude, the MEC test can be administered to patients with dementia or MCI, particularly a selection of a sub-set of 14 tests. Keywords: diagnostics, dementia, mild cognitive impairment (MCI), speech-language therapy, cognitive communication disorder

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Avila, L. M., L. S. Santos, L. P. C. Monteiro et D. M. Prata. « DIESEL CONVERSION MAXIMIZATION IN A FT MULTI-BED REACTOR ». Latin American Applied Research - An international journal 49, n^o 3 (31 juillet 2019) : 149–54. http://dx.doi.org/10.52292/j.laar.2019.336.

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Recently, modeling and simulation of the diesel production process via Fischer Tropsch (FT) have been the subject of study by several re-searchers. However, studies involving the optimiza-tion of FT technology are scarce, principally pro-cesses involving Fixed Bed Reactors (FBR). The present work aims to simulate and optimize a multi-tubular FT FBR in which the goal is to maximize the diesel production. In this way, the modeling, simulation and optimization of FT process were proposed. The reactor model is based on the one-dimensional pseudo-homogeneous model in which mass and energy balances were taken into account. The resultant ordinary differential equation system was solved by the use of the Adams Moulton meth-od, while the Interior Point method was used for the optimization step. The algorithm was then imple-mented into the Scilab solver. Several case studies were performed, evidencing that the temperature of the cooling fluid and H2/CO ratio fluid significantly impacts the conversion of the reaction.

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S, Jacob, et Karikalan L. « Optimization of Combustion Characteristics of Diesel Engine Fueled by Biofuels and Its Diesel Blends with Additive Titanium Dioxide Nano-Particles ». International Journal of Heat and Technology 39, n^o 6 (31 décembre 2021) : 1973–78. http://dx.doi.org/10.18280/ijht.390636.

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The fuel crisis throughout the world made many countries to be aware of their vulnerability to oil shortages. So many researches are still in progress and focus on the growth of bio fuel usage. In this regard, alternative fuels and the drivetrain play a major rule in critical emission issues. However, at the same time, enormous and vast number of vehicles have started to claim and place their heavy demand for alternative sources of fuel. Of course, gasoline and diesel, the conventional fuels will become scarce and much costlier. With a present known reserves and steep rise of demand and rate of consumption, hope of crude oil import is not going to last long. The CFD investigation is to find the combustion characteristics of the BioFuel with the various compositions of mixing with diesel, the Kirloskar IC Engine is taken for this research and the results of pressure, velocity, turbulence kinetic energy, temperature gradients, fuel combustions, oxidizers volume fractions also obtained from the CFD analysis results. CFD Analysis of Biodiesel combustion done in ANSYS Fluent. Software modeling of IC Engine done in CATIA V5 Software. Jatropha Methyl Ester (JME) and Mahua Methyl Ester (MME) are used for this research. Combustion characteristics in addition to emission parameters are assessed then a conclusion can be drawn.

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Wong, Ka In, Pak Kin Wong et Chun Shun Cheung. « Modelling and Prediction of Particulate Matter,NOx, and Performance of a Diesel Vehicle Engine under Rare Data Using Relevance Vector Machine ». Journal of Control Science and Engineering 2012 (2012) : 1–9. http://dx.doi.org/10.1155/2012/782095.

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Traditionally, the performance maps and emissions of a diesel engine are obtained empirically through many testes on the dynamometers because no exact mathematical engine model exists. In the current literature, many artificial-neural-network- (ANN-) based approaches have been developed for diesel engine modelling. However, the drawbacks of ANN would make itself difficult to be put into some practices including multiple local minima, user burden on selection of optimal network structure, large training data size, and overfitting risk. To overcome the drawbacks, this paper proposes to apply one emerging technique, relevance vector machine (RVM), to model the diesel engine, and to predict the emissions and engine performance. With RVM, only a few experimental data sets can train the model due to the property of global optimal solution. In this study, the engine speed, load, and coolant temperature are used as the input parameters, while the brake thermal efficiency, brake-specific fuel consumption, concentrations of nitrogen oxides, and particulate matter are used as the output parameters. Experimental results show the model accuracy is fairly good even the training data is scarce. Moreover, the model accuracy is compared with that using typical ANN. Evaluation results also show that RVM is superior to typical ANN approach.

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Ampah, Jeffrey Dankwa, Abdulfatah Abdu Yusuf, Ephraim Bonah Agyekum, Sandylove Afrane, Chao Jin, Haifeng Liu, Islam Md Rizwanul Fattah et al. « Progress and Recent Trends in the Application of Nanoparticles as Low Carbon Fuel Additives—A State of the Art Review ». Nanomaterials 12, n^o 9 (29 avril 2022) : 1515. http://dx.doi.org/10.3390/nano12091515.

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The first part of the current review highlights the evolutionary nuances and research hotspots in the field of nanoparticles in low carbon fuels. Our findings reveal that contribution to the field is largely driven by researchers from Asia, mainly India. Of the three biofuels under review, biodiesel seems to be well studied and developed, whereas studies regarding vegetable oils and alcohols remain relatively scarce. The second part also reviews the application of nanoparticles in biodiesel/vegetable oil/alcohol-based fuels holistically, emphasizing fuel properties and engine characteristics. The current review reveals that the overall characteristics of the low carbon fuel–diesel blends improve under the influence of nanoparticles during combustion in diesel engines. The most important aspect of nanoparticles is that they act as an oxygen buffer that provides additional oxygen molecules in the combustion chamber, promoting complete combustion and lowering unburnt emissions. Moreover, the nanoparticles used for these purposes exhibit excellent catalytic behaviour as a result of their high surface area-to-volume ratio—this leads to a reduction in exhaust pollutants and ensures an efficient and complete combustion. Beyond energy-based indicators, the exergy, economic, environmental, and sustainability aspects of the blends in diesel engines are discussed. It is observed that the performance of the diesel engine fuelled with low carbon fuels according to the second law of efficiency improves under the influence of the nano-additives. Our final part shows that despite the benefits of nanoparticles, humans and animals are under serious threats from the highly toxic nature of nanoparticles.

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Hauser-Davis, Rachel Ann. « Vulnerability of small-scale fishers to benzene exposure and the current knowledge gap on benzene-exposure in Brazilian fishers ». PeerJ 7 (13 août 2019) : e7483. http://dx.doi.org/10.7717/peerj.7483.

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Fishers are a particularly vulnerable population, chronically exposed to many stresses, injuries and health conditions directly linked to their fishing activities. This includes benzene exposure through gasoline and diesel exhaust fumes. Benzene is a known carcinogen, and has been assessed in many worker groups, but reports on fisher benzene exposure are extremely scarce in the literature. This paper discusses benzene exposure in small-scale fishers and reflects on the current knowledge gap on benzene-exposure in Brazilian fishers.

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Wei, Mingrui, Gao Ji, Jinping Liu et Song Li. « Development and validation of a reduced MF/biodiesel mechanism for diesel engine application ». Thermal Science, n^o 00 (2022) : 130. http://dx.doi.org/10.2298/tsci220509130w.

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2-methylfuran (MF) is widely used as a surrogate fuel for internal combustion engines. However, the chemical kinetics model of MF for engine combustion simulations remains scarce. In this paper, a reduced MF/biodiesel mechanism consisting of 82 species and 226 reactions was proposed and used to simulate the combustion process of MF and biodiesel dual-fuel diesel engine. First, a detailed chemical reaction mechanism of MF was selected and then mechanism reduction methods were used to reduce the detailed mechanism under engine conditions. Second, the reduced MF mechanism was coupled with a biodiesel mechanism to form a four-component chemistry mechanism, consisting of MD, MD9D, n-heptane and MF. Third, the combined mechanism was optimized by using rate of production analysis and sensitivity analysis. Finally, the proposed four-component mechanism was verified by comparing the calculated values of ignition delay and species concentrations with the experimental values. Meanwhile, a new dual-fuel diesel engine test was carried out, and the experiments were used to evaluate the reliability of the combination mechanism. Overall, the simulated results of the proposed four-component mechanism in this paper are basically consistent with the experimental results.

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Ventura, Loris, Roberto Finesso et Stefano A. Malan. « Development of a Model-Based Coordinated Air-Fuel Controller for a 3.0 dm3 Diesel Engine and Its Assessment through Model-in-the-Loop ». Energies 16, n^o 2 (13 janvier 2023) : 907. http://dx.doi.org/10.3390/en16020907.

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The tightening of diesel pollutant emission regulations has made Internal Combustion Engine (ICE) management through steady-state maps obsolete. To overcome the map’s scarce performance and efficiently manage the engine, control systems must cope with ICE transient operations, the coupling between its subsystem dynamics, and the tradeoff between different requirements. The work demonstrates the effectiveness of a reference generator that coordinates the air path and combustion control systems of a turbocharged heavy-duty diesel engine. The control system coordinator is based on neural networks and allows for following different engine-out Nitrogen Oxide (NOx) targets while satisfying the load request. The air path control system provides the global conditions for the correct functioning of the engine, targeting O2 concentration and pressure in the intake manifold. Through cooperation, the combustion control targets Brake Mean Effective Pressure (BMEP) and NOx to react to rapid changes in the engine operating state and compensates for the remaining deviations with respect to load and NOx targets. The reference generator and the two controller algorithms are suitable for real-time implementation on rapid-prototyping hardware. The performance overall was good, allowing the engine to follow different NOx targets with 150 ppm of deviation and to achieve an average BMEP error of 0.3 bar.

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Davis, Stacy C., et Lorena F. Truett. « Sales and Impact of Class 2b Trucks ». Transportation Research Record : Journal of the Transportation Research Board 1842, n^o 1 (janvier 2003) : 1–8. http://dx.doi.org/10.3141/1842-01.

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Vehicles in the upper portion of the Class 2 weight range [6,000 to 10,000 lb gross vehicle weight rating (GVWR)] were identified and examined, and their impact was assessed. Class 2b vehicles (GVWR of 8,500 to 10,000 lb) include pickup trucks, sport utility vehicles, and large vans. Oak Ridge National Laboratory researched each individual truck model to determine which models were Class 2b trucks and developed four methodologies to derive sales volumes. Two methods were recommended for producing believable and reliable results. The results of the study indicate that in calendar year 1999, 521,000 Class 2b vehicles (6.4% of sales of all trucks under 10,000 lb) were sold; 82% of Class 2b vehicles sold were pickups, and one-third of Class 2b vehicles sold had diesel engines. In 2000, 5.8 million Class 2b vehicles (7.8% of all trucks under 10,000 lb) were on the road; 24% of the Class 2b vehicle population had diesel engines, and Class 2b vehicles accounted for 8% of annual miles traveled by trucks under 10,000 lb and 9% of fuel use. Data on Class 2b vehicles are scarce. As the Tier 2 standards (which apply to passenger vehicles in the 8,500 to 10,000 lb GVWR category) become effective, additional data—not only about emissions, but also about all areas—on Class 2b vehicles may become available. At the moment, distinguishing Class 2b vehicles from all Class 2 vehicles is a substantial task that requires individual model data.

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Wu, Xiao Chun, et Zhong Jun Wang. « Investigation on a Novel Seawater Exhaust Gas Cleaning System Applied for SO_x Emissions Reduction of Marine Diesel Engine ». Advanced Materials Research 1010-1012 (août 2014) : 765–71. http://dx.doi.org/10.4028/www.scientific.net/amr.1010-1012.765.

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The control and regulation of SOx emissions have become a global urgent problem for the environment protection. In the field of ocean and marine engineering, The International Maritime Organization (IMO) has formally passed the amendment of MARPOL 73/78 Annex VI in 2008 that clarified the deadline of requirements on SOx emissions limit. A limitation of 3.5 %mm is strictly requested during 2012 to 2020. Hence the SOx emissions of marine diesel engines faces unprecedented challenges while effective control and regulation systems on the SOx emissions reduction are scarce in the existing ships. To meet the IMO's requirements, this paper has presented a novel seawater exhaust gas cleaning (EGC) system for the SOx emissions reduction of marine diesel engines. The post-combustion desulfurization technology was employed in the EGC system. The carbon ion and hydrogen ion contained in the seawater have been introduced into the EGC system to participant the reaction of desulfurization. The seawater EGC system has already been established in a real ship. Experiments have been carried out with the established seawater EGC system to comparatively analyze SOX emissions characteristics when burning different oil types, including heavy oil and light oil. The experiment results show that the newly established seawater EGC system can achieve satisfactory performance with a desulfurization efficiency of 88%. More important, the standard of the SOX emission limitation set by IMO has been met by using the proposed EGC system.

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Corsini, Alessandro, et Eileen Tortora. « Sea-Water Desalination for Load Levelling of Gen-Sets in Small Off-Grid Islands ». Energies 11, n^o 8 (8 août 2018) : 2068. http://dx.doi.org/10.3390/en11082068.

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This study deals with the energy/water nexus on small off-grid islands. Small islands share several characteristics that hinder the introduction of new plants, such as: Energy system balance when renewable sources are introduced; water shortages, usually addressed via shipping from the mainland; environmental and historical heritage values; and, scarce land availability. In these cases, it is mandatory to detect energy/water technology integration and management solutions respecting the peculiarities and boundaries of the sites. The present work proposes a desalination plant with a primary scope of load leveler and a secondary scope of water producer. The aim is to propose a simple and non-invasive solution for energy/water management in order to limit impacts on the local environment while improving the match between renewable energy and local generation by means of desalination. This study led to an integrated system composed of local diesel engine power plant, distributed roof-top photovoltaic plants and a desalination plant, managed by a dedicated control logic. Desalination from renewable energy and power adjustments of already active diesel engines are favored. The case study refers to Ponza island, in the Tyrrhenian Sea. This paper demonstrates the effective possibility of using a desalination plant with the double purpose of water production and load levelling, providing 98% of the local water demand while mitigating the renewable energy fluctuations effects on the gen-set. Moreover, the proposed system results in a 50% CO2eq emissions abatement over the current water supply carbon footprint.

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Stepanenko, Denys, et Zbigniew Kneba. « ECU calibration for gaseous dual fuel supply system in compression ignition engines ». Combustion Engines 182, n^o 3 (30 septembre 2020) : 33–37. http://dx.doi.org/10.19206/ce-2020-306.

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The dual fuel (DF) combustion mode is proven solution that allows to improve or get at the same level engine performance and reduce toxic compounds in exhaust gases which is confirmed by researchers and end-users. DF combustion mode uses two fuels gaseous fuel as a primary energy source and a pilot quantity of diesel fuel as ignition source. However, in order, to fully take advantage of the potential of the dual fuel mode, DF system must be proper calibrated. Despite the existence of commercial control systems for dual fuel engines on the market, the literature on the important parameters for the engine's operation introduced during calibration is scarce. This article briefly describes a concept of working algorithm and calibration strategy of a dual fuel electronic control unit (ECU) The purpose of calibration is to achieve the greatest possible use of an alternative gaseous fuel without causing accelerated engine wear.

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Mateos, Ana Carolina, Iván Tavera Busso, Hebe Alejandra Carreras et Claudia María González. « Assessment of diesel exhaust pollutants effects in Tillandsia capillaris and Ramalina celastri by laboratory trials ». Revista Internacional de Contaminación Ambiental 38 (8 novembre 2022) : 349–63. http://dx.doi.org/10.20937/rica.54205.

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Traffic-related air pollution is one of the most relevant environmental problems in urban areas. Several cryptogams (i.e., lichens and mosses) and vascular species have been employed to monitor urban air pollution since they allow the assessment of air quality in a large number of sampling sites simultaneously at low cost. In large urban cities, vehicle emissions are frequently the major source of air pollution along with residential energy (for cooking and heating), industry, power generation, and waste incineration. Biomonitors in these urban environments are exposed to a mixture of pollutants making it difficult to identify which pollutant causes the greatest damage to organisms. However, studies that analyze the effect of pollutants emitted by vehicle exhaust are scarce and in the particular case of the most used biomonitor species in Argentina, no analysis of how they are affected by vehicle emissions has been carried out so far. So, the aim of this work was to analyze changes in physiochemical parameters (pigment content, pro-oxidant products, and sulfur accumulation) in Ramalina celastri, and heavy metal accumulation in Tillandsia capillaris, exposed to diesel exhausts under laboratory conditions. A strong damage in the photosynthetic apparatus of R. celastri was observed as well as metal concentration in T. capillaris after 20 min of exposure and 48 h of permanence in the exposure chambers. The results indicate that not only the particles and metals cause damage to these two well-known biomonitors, but the interaction of these pollutants with other components of the atmosphere that form different secondary pollutants, together with a longer exposure time, could cause the highest level of damage in them.

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Abdulkareem, Simiat Bidemi. « Patterns of Corruption in Ahmadu Bello University Teaching Hospital Shika, Zaria, Kaduna State, Nigeria ». Nigerian Journal of Sociology and Anthropology 18, n^o 1 (1 juin 2020) : 99–113. http://dx.doi.org/10.36108/njsa/0202/81(0170).

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In Nigeria, corruption is the obstacle preventing the country from achieving its enormous potential.Corruption in the health sector is a concern in Nigeria where public resources are already scarce. Corruption in the health sector has made various health institutions to be ineffective while scarce resources invested in the sector are wasted. It weakens the social contract between the government and its people, and drains billions of dollars annually from the country’s economy. The deplorable condition of thehealth sector in Nigeria, in spite of government spending raises serious concerns. Theseconcerns include mismanagement, embezzlement, poor funding, shortage of drugs and medicalequipment in public hospitals etc. This paper therefore examines how corruption has impeded on theservice delivery in Ahmadu Bello University Teaching Hospital (ABUTH) Shika, Zaria. The main objective of this study is toinvestigate the effect of corruption on service delivery and how it affects patients in the study area. Data were collected from the targeted populations through in-depth interviews and focus group discussions. The findings revealed that there is diversion of drugs, injections and other materials for personal use and sales, also money meant for fuel and diesel diverted to personal pocket. It is recommended that any health workers caught in one corrupt act or the other should be dealt with severely to serve as deterrent to others and also Federal Ministry of Health should procure and distribute drugs and other medical materials needed in the hospital and the public must be aware of the drugs that are free.

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Gonçalves, Daniel Neves Schmitz, George Vasconcelos Goes, Márcio de Almeida D’Agosto et Emilio Lebre La Rovere. « Development of Policy-Relevant Dialogues on Barriers and Enablers for the Transition to Low-Carbon Mobility in Brazil ». Sustainability 14, n^o 24 (8 décembre 2022) : 16405. http://dx.doi.org/10.3390/su142416405.

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Establishing viable targets and pathways to achieve low-carbon mobility is proving to be a growing challenge, especially in emerging economies. Brazil has faced persistent economic and political crises, impacting current and future climate policies. The acceleration of resource exploitation and environmental degradation has increased the role of the transport sector in mitigating Brazilian emissions. Despite advances in instruments aimed at high-capacity infrastructure and the biodiesel and ethanol markets, electric mobility and other advanced biofuels, such as biokerosene and green diesel, are moving slowly. Part of this stems from severe technical, policy, and financial barriers that need to be addressed. This paper identifies the main barriers faced and the instruments needed to accelerate decarbonization in the Brazilian transport sector. To this purpose, a stakeholder-oriented approach is developed and applied to distill low-carbon opportunities and enablers over the next decade. This article reveals the important relationship between climate commitments, the different obstacles faced, and the possible consequences, taking different perspectives on appropriate reference points. By 2025, instruments aimed at electric mobility and public transport, although still scarce in current policies, will have greater potential for implementation. This contrasts with other advanced biofuels, which are not expected until the end of the decade.

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Cui, Min, Yingjun Chen, Yanli Feng, Cheng Li, Junyu Zheng, Chongguo Tian, Caiqing Yan et Mei Zheng. « Measurement of PM and its chemical composition in real-world emissions from non-road and on-road diesel vehicles ». Atmospheric Chemistry and Physics 17, n^o 11 (9 juin 2017) : 6779–95. http://dx.doi.org/10.5194/acp-17-6779-2017.

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Abstract. With the rapid growth in the number of both non-road and on-road diesel vehicles, the adverse effects of particulate matter (PM) and its constituents on air quality and human health have attracted increasing attentions. However, studies on the characteristics of PM and its composition emitted from diesel vehicles are still scarce, especially under real-world driving conditions. In this study, six excavators and five trucks that provided a wide range of emission standards and operation modes were tested, and PM emissions and their constituents – including organic carbon (OC), elemental carbon (EC), water-soluble ions (WSIs), elements, and organic species like polycyclic aromatic hydrocarbons (PAHs), n-alkanes, and hopanes – as well as steranes were analyzed and characterized. The average emission factors for PM (EFPM) from excavator and truck emissions were 829 ± 806 and 498 ± 234 mg kg−1 fuel, respectively. EFPM and PM constituents were significantly affected by fuel quality, operational mode, and emission standards. A significant correlation (R2 = 0. 79, p < 0. 01) was found between EFPM for excavators and the sulfur contents in fuel. The highest average EFPM for working excavators was 904 ± 979 mg kg−1 fuel as a higher engine load required in this mode. From pre-stage 1 to stage 2, the average EFPM for excavators decreased by 58 %. For trucks, the average non-highway EFPM at 548 ± 311 mg kg−1 fuel was higher than the highway EFPM at 497 ± 231 mg kg−1 fuel. Moreover, the reduction rates were 63.5 and 65.6 % when switched from China II and III to China IV standards, respectively. Generally, the PM composition emitted from excavators was dominated by OC (39. 2 ± 21. 0 %) and EC (33. 3 ± 25. 9 %); PM from trucks was dominated by EC (26. 9 ± 20. 8 %), OC (9. 89 ± 12 %), and WSIs (4. 67 ± 5. 74 %). The average OC ∕ EC ratios for idling and working excavators were 3 to 4 times higher than those for moving excavators. Although the EFPM for excavators and trucks was reduced with the constraint of regulations, the element fractions for excavators increased from 0.49 % in pre-stage 1 to 3.03 % in stage 2, and the fraction of WSIs for the China IV truck was 5 times higher than the average value of all other-level trucks. Furthermore, as compared with other diesel vehicles, wide ranges were found for excavators of the ratios of benzo[a]anthracene ∕ (benzo[a]anthracene + chrysene) (0.26–0.86), indeno[1,2,3-cd]pyrene ∕ (indeno[1,2,3-cd]pyrene + benzo[ghi]perylene) (0.20–1.0), and fluoranthene ∕ (fluoranthene + pyrene) (0.24–0.87), which might be a result of the complex characteristics of the excavator operation modes. A comparison of our results with those in the literature revealed that on-board measurement data more accurately reflect actual conditions. Although the fractions of the 16 priority PAHs in PM from the excavator and truck emissions were similar, the equivalent concentrations of total benzo[a]pyrene of excavators were 31 times than that for trucks, implying that more attention should be paid to non-road vehicle emissions.

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Schultze, T., et M. Bues. « Neue Wege zur Qualifikation/VR-based training and Education : A new way of Qualification ». wt Werkstattstechnik online 110, n^o 07-08 (2020) : 572–75. http://dx.doi.org/10.37544/1436-4980-2020-07-08-116.

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Top-qualifiziertes Personal in Produktion und Service ist bereits heute eine knappe Ressource. Training und Weiterbildung sind jedoch oftmals teuer, und die Schulung an Produkt oder Produktionsanlage ist oft nur sehr eingeschränkt möglich. Virtual Reality (VR) ist ein entscheidender Baustein zur Lösung dieser Probleme: Service- und Produktionsprozesse werden realistisch am virtuellen 1:1-Objekt trainiert, mit und ohne Unterstützung durch einen erfahrenen Instruktor und an beliebigen Orten. Letzteres ist gerade in der durch das Corona-Virus bedingten Situation des Jahres 2020 von besonderer Bedeutung.   Top-qualified personnel in production and service is already a scarce resource today. However, training and further education are often expensive, and training on products or production equipment is often only possible to a very limited extent. Virtual Reality (VR) is a decisive component in solving these problems: service and production processes are trained realistically on a virtual 1:1 object, with or without the support of an experienced instructor and at any location. The latter is particularly relevant in the situation of the year 2020 caused by the corona virus.

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Darantiah Ruing, Gregory Rama, Antonius Ibi Weking et Lie Jasa. « ANALISIS DAN PERBANDINGAN SEGITIGA KERJA : TURBIN SUDU SETENGAH LINGKARAN, SUDU SEGITIGA DAN SUDU SIRIP UNTUK MENGHASILKAN RPM YANG TERTINGGI ». Jurnal SPEKTRUM 6, n^o 2 (1 juin 2019) : 78. http://dx.doi.org/10.24843/spektrum.2019.v06.i02.p12.

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At present the power plant has a high dependence on energy sources such as diesel, natural gas and coal, while its energy source in nature is increasingly scarce, this situation encourages the development of renewable energy, one of which is in micro hydro power plants. This study aims to determine the effect of the width of the work triangle on the highest rpm produced. the fall of water on the pinwheel is set from the position angle of the nozzle 00, 150, 300, 450, 600, 750 and from the angle of the nozzle 00, 50, 100, 150, 200, 250, 300, 350 and 400 on the semicircular blade turbine, triangle blade turbine , and fin blade turbines. Semicircular turbine blade, working triangle area produces greater rpm at position of angle nozzle 00 and angle of nozzle 250 with area of work triangle 360,36 cm2, where the position produces 216 rpm at windmill rotation and 1626 rpm at generator rotation. When the nozzle position angle 150 and the nozzle angle 200 with the working triangle area 264.27 cm2, produce 221 rpm at the pinwheel rotation and 1711 rpm at the generator rotation. while at the nozzle position angle of 300 and the angle of the nozzle 100 the area of the triangle works 134.37 cm2 and produces 173 rpm at the spinning wheel and 1307 rpm at the generator rotation. on the triangle blade turbine and fin blade, the working triangle area does not affect the rpm produced.

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Lanzilotti, Cledson Oliveira, Luiz Fernando Rodrigues Pinto, Francesco Facchini et Salvatore Digiesi. « Embedding Product-Service System of Cutting Tools into the Machining Process : An Eco-Efficiency Approach toward Sustainable Development ». Sustainability 14, n^o 3 (18 janvier 2022) : 1100. http://dx.doi.org/10.3390/su14031100.

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Product-Service System (PSS) is a sustainable strategy that shifts the focus of the business from selling physical products to providing service by using the product. The innovation proposed in the PSS, focused on sustainable production and consumption, is consistent with the sustainable development goals of the United Nations 2030 Agenda. The scientific literature on PSS in machining showed studies that address the economic factor of PSS contract, machine maintenance and logistics and operational process improvement. Then, there is a lack of studies on the assessment of the PSS in machining under a sustainability factors perspective. Thus, the objective of this paper was to evaluate the economic, environmental, and social advantages of PSS cutting tools in machining. Consistent with this aim, the research focused on a case study in a diesel engine parts machining company. From an economic point of view, the results indicated a reduction in operating costs of US$ 1,206,080 per year, which allowed a nine-month return on investment. From an ecological perspective, the recovery of 602 kg of carbide per year mitigated the environmental impact of tungsten and cobalt exploration. These results are even more expressive because it deals with scarce metals. Furthermore, technological advances reduced the risk of injury to operators. This research increased knowledge on PSS in machining by presenting an original study that led the analysis under a sustainability perspective. Moreover, this study contributes to managers by showing the business model’s advantages that reduce operating costs and socio-environmental impacts, enhancing sustainable development.

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Aitlaalim, Abdellah, Fatiha Ouanji, Abdellah Benzaouak, Mohammed El Mahi, El Mostapha Lotfi, Mohamed Kacimi et Leonarda Francesca Liotta. « Utilization of Waste Grooved Razor Shell (GRS) as a Catalyst in Biodiesel Production from Refined and Waste Cooking Oils ». Catalysts 10, n^o 6 (22 juin 2020) : 703. http://dx.doi.org/10.3390/catal10060703.

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Biodiesel is a potential alternative for fossil fuel. However, its large-scale application is held up by the disadvantage of a homogenous process, the scarce availability of raw materials and the production cost, which is higher than for fossil diesel. In this work, biodiesel production was carried out using both refined and used cooking oils. The process was investigated in a batch reactor, in the presence of CaO as a heterogeneous catalyst prepared by the calcination of the natural Waste Grooved Razor Shell (GRS). Characterizations by X-Ray Diffraction (XRD) and Thermal Gravimetric (TG)/Differential Thermal Analysis (DTA) showed that the as-received GRS consists of aragonite, (i.e., CaCO3) as the main component and of water and organic matter in a lower amount. After calcination at 900 °C, CaO was formed as the only crystalline phase. The effects of several experimental parameters in the transesterification reactions were studied, and their impact on the produced biodiesel properties was investigated. The studied variables were the methanol/oil molar ratio, the catalyst weight percentage (with respect to the oil mass), the calcination temperature of the parent GRS and the recycling and regeneration of the catalyst. The physico-chemical and fuel properties, i.e., viscosity, density and acid value of used oils and of the produced biodiesel, were determined by conventional methods (American Society for Testing and Materials (ASTM) methods) and compared with the European standards of biodiesel. The optimal identified conditions were the following: the use of a 15:1 methanol/oil molar ratio and 5 wt% of CaO with respect to the oil mass. After 3 h of reaction at 65 °C, the biodiesel yield was equal to 94% and 99% starting from waste and refined oils, respectively.

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Karunamurthy, Krishnasamy, Mohammed Musthafa Feroskhan, Ganesan Suganya et Ismail Saleel. « Prediction and optimization of performance and emission characteristics of a dual fuel engine using machine learning ». International Journal for Simulation and Multidisciplinary Design Optimization 13 (2022) : 13. http://dx.doi.org/10.1051/smdo/2022002.

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The current research in engine, fuel and lubricant development are aiming towards environmental protection by reducing the harmful emissions. The testing under various conditions becomes mandatory before releasing product to meet the sustainable development goals of United Nations. This experimentation and testing under various operating conditions is time-consuming and tiresome process; it also leads to wastage of manpower, money, precious time and scarce resources. Intelligent techniques like Machine Learning (ML) has proven it's usage in almost all domains, trying to simulate the results as trained. This advantage is used to predict the performance and emission characteristics of a dual fuel engine. In this study, the experimental data are obtained from a single cylinder CI engine by operating under dual fuel mode using biogas and diesel as primary and secondary fuel respectively. The input parameters such as biogas flow rate, methane fraction (MF), torque and intake temperature are considered to predict the output parameters. The output parameters of the study includes performance attributes Brake thermal efficiency, secondary fuel energy ratio, and emissions attributes HC, CO, NOx and smoke. The proposed model uses Random forest Regressor and is trained using 324 distinct experiences recorded through physical experimentation. The model is validated using R2 score which is observed to be 0.997 for the given dataset while trained and tested in the ratio of 85:15. The outputs of the model are used to compute the output data for any new values of input attributes. The optimized values of the input parameters that could give maximum thermal efficiency and minimum emission is found using Lagrangian optimization. The optimized values are 12.48 Nm torque, 8.29 lit/min of biogas flow rate, methane fraction of 72.8%, intake temperature of 68.3 °C.

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Li, Ying, Douglas A. Day, Harald Stark, Jose L. Jimenez et Manabu Shiraiwa. « Predictions of the glass transition temperature and viscosity of organic aerosols from volatility distributions ». Atmospheric Chemistry and Physics 20, n^o 13 (13 juillet 2020) : 8103–22. http://dx.doi.org/10.5194/acp-20-8103-2020.

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Abstract. Volatility and viscosity are important properties of organic aerosols (OA), affecting aerosol processes such as formation, evolution, and partitioning of OA. Volatility distributions of ambient OA particles have often been measured, while viscosity measurements are scarce. We have previously developed a method to estimate the glass transition temperature (Tg) of an organic compound containing carbon, hydrogen, and oxygen. Based on analysis of over 2400 organic compounds including oxygenated organic compounds, as well as nitrogen- and sulfur-containing organic compounds, we extend this method to include nitrogen- and sulfur-containing compounds based on elemental composition. In addition, parameterizations are developed to predict Tg as a function of volatility and the atomic oxygen-to-carbon ratio based on a negative correlation between Tg and volatility. This prediction method of Tg is applied to ambient observations of volatility distributions at 11 field sites. The predicted Tg values of OA under dry conditions vary mainly from 290 to 339 K and the predicted viscosities are consistent with the results of ambient particle-phase-state measurements in the southeastern US and the Amazonian rain forest. Reducing the uncertainties in measured volatility distributions would improve predictions of viscosity, especially at low relative humidity. We also predict the Tg of OA components identified via positive matrix factorization of aerosol mass spectrometer (AMS) data. The predicted viscosity of oxidized OA is consistent with previously reported viscosity of secondary organic aerosols (SOA) derived from α-pinene, toluene, isoprene epoxydiol (IEPOX), and diesel fuel. Comparison of the predicted viscosity based on the observed volatility distributions with the viscosity simulated by a chemical transport model implies that missing low volatility compounds in a global model can lead to underestimation of OA viscosity at some sites. The relation between volatility and viscosity can be applied in the molecular corridor or volatility basis set approaches to improve OA simulations in chemical transport models by consideration of effects of particle viscosity in OA formation and evolution.

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Alghamdi, Mansour A., Salwa K. Hassan, Noura A. Alzahrani, Marwan Y. Al Sharif et Mamdouh I. Khoder. « Classroom Dust-Bound Polycyclic Aromatic Hydrocarbons in Jeddah Primary Schools, Saudi Arabia : Level, Characteristics and Health Risk Assessment ». International Journal of Environmental Research and Public Health 17, n^o 8 (17 avril 2020) : 2779. http://dx.doi.org/10.3390/ijerph17082779.

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Data concerning polycyclic aromatic hydrocarbons (PAHs) in Jeddah’s schools, Saudi Arabia, and their implications for health risks to children, is scarce. Classroom air conditioner filter dusts were collected from primary schools in urban, suburban and residential areas of Jeddah. This study aimed to assess the characteristics of classroom-dust-bound PAHs and the health risks to children of PAH exposure. Average PAH concentrations were higher in urban schools than suburban and residential schools. Benzo (b)fluoranthene (BbF), benzo(ghi)perylene (BGP), chrysene (CRY) and Dibenz[a,h]anthracene (DBA) at urban and suburban schools and BbF, BGP, fluoranthene (FLT) and indeno (1, 2, 3, −cd)pyrene (IND) at residential schools were the dominant compounds in classroom dust. PAHs with five aromatic rings were the most abundant at all schools. The relative contribution of the individual PAH compounds to total PAH concentrations in the classroom dusts of schools indicate that the study areas do share a common source, vehicle emissions. Based on diagnostic ratios of PAHs, they are emitted from local pyrogenic sources, and traffic is the significant PAH source, with more significant contributions from gasoline-fueled than from diesel cars. Based on benzo[a]pyrene equivalent (BaPequi) calculations, total carcinogenic activity (TCA) for total PAHs represent 21.59% (urban schools), 20.99% (suburban schools), and 18.88% (residential schools) of total PAH concentrations. DBA and BaP were the most dominant compounds contributing to the TCA, suggesting the importance of BaP and DBA as surrogate compounds for PAHs in this schools. Based on incremental lifetime cancer risk (ILCingestion, ILCRinhalation, ILCRdermal) and total lifetime cancer risk (TLCR)) calculations, the order of cancer risk was: urban schools > suburban schools > residential schools. Both ingestion and dermal contact are major contributors to cancer risk. Among PAHs, DBA, BaP, BbF, benzo(a)anthracene (BaA), benzo(k)fluoranthene (BkF), and IND have the highest ILCR values at all schools. LCR and TLCR values at all schools were lower than 10−6, indicating virtual safety. DBA, BaP and BbF were the predominant contributors to cancer effects in all schools.

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Niki, Yoichi. « Reductions in Unburned Ammonia and Nitrous Oxide Emissions From an Ammonia-Assisted Diesel Engine With Early Timing Diesel Pilot Injection ». Journal of Engineering for Gas Turbines and Power 143, n^o 9 (31 mai 2021). http://dx.doi.org/10.1115/1.4051002.

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Abstract The global drive to limit the effects of climate change affords a strong incentive to reduce CO2 emissions. H2 is one of the cleanest energy sources, because its combustion does not produce CO2. It is well known that NH3 stores as well as carries H2 and does not produce CO2 on combustion. NH3 has been investigated for its use as an alternative fuel and for use in internal combustion engines. Investigations of NH3 and N2O emissions from NH3-assisted diesel engines operated using NH3–diesel dual fuel have been scarce. NH3 and N2O cause air pollution and are toxic to humans; therefore, these pollutants should be reduced to acceptable levels. In addition, N2O is a greenhouse gas with high global warming potential. In this study, a combustion strategy was developed to reduce NH3 and N2O emissions from an NH3-assisted diesel engine. NH3 and diesel fuel worked as low- and high-reactivity fuels, respectively, in our strategy for reactivity-controlled compression ignition combustion. The present paper reports the insights obtained from an understanding of the chemical processes of diesel fuel ignition and NH3 decomposition. Experiments revealed the effects of advancing diesel pilot injection timing on emissions and combustion performance, and the manipulation of combustion phasing using a change in the amount of injected diesel fuel and NH3. Finally, the reduction in greenhouse gas emissions considering the global warming effects of N2O was estimated using an NH3-assisted diesel engine that applied the proposed combustion strategy.

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Gopal Gupta, Jai, Avinash Kumar Agarwal et Suresh K. Aggarwal. « Particulate Emissions From Karanja Biodiesel Fueled Turbocharged CRDI Sports Utility Vehicle Engine ». Journal of Energy Resources Technology 137, n^o 6 (23 juillet 2015). http://dx.doi.org/10.1115/1.4031006.

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Biodiesel has emerged as one of the most promising alternative fuel to mineral diesel in last two decades globally. Lower blends of biodiesel emit fewer pollutants, while easing pressure on scarce petroleum resources, without sacrificing engine power output and fuel economy. However, diesel engines emit significant amount of particulate matter (PM), most of which are nanoparticles. Due to the adverse health impact of PM emitted by compression ignition (CI) engines; most recent emission legislations restrict the total number of particles emitted, in addition to PM mass emissions. Use of biodiesel leads to reduction in PM mass emissions; however, the particle size–numbers distribution has not been investigated thoroughly. In this paper, PM emission characteristics from Karanja biodiesel blends (KB20 and KB40) in a modern common rail direct injection (CRDI) engine used in a sports utility vehicle (SUV) with a maximum fuel injection pressure of 1600 bar have been reported. This study also explored comparative effect of varying engine speeds and loads on particulate size–number distribution, particle size–surface area distribution, and total particulate number concentration from biodiesel blends vis-à-vis baseline mineral diesel. This study showed that particulate number emissions from Karanja biodiesel blends were relatively higher than baseline mineral diesel.

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Sofimieari, Ibim, Mohd Wazir Bin Mustafa et Felix Obite. « Modelling and analysis of a PV/wind/diesel hybrid standalone microgrid for rural electrification in Nigeria ». Bulletin of Electrical Engineering and Informatics 8, n^o 4 (1 décembre 2019). http://dx.doi.org/10.11591/eei.v8i4.1608.

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The scarce electricity supply in Nigeria is a key factor to the low industrial development in a country well-known for having the least electrification in Africa per capita. Presently, Nigeria employs four different kinds of energy such as coal, natural gas, hydro, and oil. Three of the four resources mentioned above used for the production of energy in Nigeria is connected with increasing emissions of greenhouse gas: natural gas, oil, and coal, with coal releasing the worst. This paper presents a model and analysis of PV/Wind/Diesel hybrid system for rural electrification in Kaduna state, northern Nigeria. HOMER (Hybrid Optimization Model for Electric Renewable) software tool was used for optimization and modeling of this work. Simulation results show that the PV/Wind/Diesel system with Battery storage is the most cost-effective system since it recorded considerable cost of energy and reduces CO2 emissions significantly.

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Hussain, E. K., Philipp R. Thies, Jon Hardwick, Peter M. Connor et Mohammad Abusara. « Grid Island Energy Transition Scenarios Assessment Through Network Reliability and Power Flow Analysis ». Frontiers in Energy Research 8 (19 février 2021). http://dx.doi.org/10.3389/fenrg.2020.584440.

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This paper presents a methodology for the reliability and power flow analysis of islands or off-grid power networks for situations of scarce data and information. It offers a new and pragmatic approach to derive the required power network information, including the power cable parameters and the load at each power node. The paper aims to present the developed methodology, and to illustrate its application, using Ushant Island as a case study. The assessment of the current power network status and the reliability analysis are presented. Grid performance parameters are further compared for conventional diesel generator operation and renewable energy generation scenarios, demonstrating the advantages of replacing the existing diesel units with renewable energy sources in terms of system reliability. The analysis shows that by introducing renewable energy systems to the island’s grid, the reliability of the grid increases by up to 50% and cable capacity usage reduces by up to 30%. Furthermore, this work suggests that it would not be necessary to modify the grid cables when substituting the diesel generator. The paper will be of interest to network planners, community stakeholders, project developers and decision-makers concerned with renewable energy investment on islands and in remote rural areas.

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Bendtsen, Katja M., Elizabeth Bengtsen, Anne T. Saber et Ulla Vogel. « A review of health effects associated with exposure to jet engine emissions in and around airports ». Environmental Health 20, n^o 1 (6 février 2021). http://dx.doi.org/10.1186/s12940-020-00690-y.

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Abstract Background Airport personnel are at risk of occupational exposure to jet engine emissions, which similarly to diesel exhaust emissions include volatile organic compounds and particulate matter consisting of an inorganic carbon core with associated polycyclic aromatic hydrocarbons, and metals. Diesel exhaust is classified as carcinogenic and the particulate fraction has in itself been linked to several adverse health effects including cancer. Method In this review, we summarize the available scientific literature covering human health effects of exposure to airport emissions, both in occupational settings and for residents living close to airports. We also report the findings from the limited scientific mechanistic studies of jet engine emissions in animal and cell models. Results Jet engine emissions contain large amounts of nano-sized particles, which are particularly prone to reach the lower airways upon inhalation. Size of particles and emission levels depend on type of aircraft, engine conditions, and fuel type, as well as on operation modes. Exposure to jet engine emissions is reported to be associated with biomarkers of exposure as well as biomarkers of effect among airport personnel, especially in ground-support functions. Proximity to running jet engines or to the airport as such for residential areas is associated with increased exposure and with increased risk of disease, increased hospital admissions and self-reported lung symptoms. Conclusion We conclude that though the literature is scarce and with low consistency in methods and measured biomarkers, there is evidence that jet engine emissions have physicochemical properties similar to diesel exhaust particles, and that exposure to jet engine emissions is associated with similar adverse health effects as exposure to diesel exhaust particles and other traffic emissions.

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Silva, Marcelle Almeida, Cinthya Mirella Pacheco, Cibele Alves dos Santos, Hugo Henrique Costa Nascimento et Rejane Jurema Mansur Custódio Nogueira. « TOLERANCE MECHANISMS IN Hymenaea courbaril L. and Jatropha curcas L. plants AS A RESPONSE TO WATER DEFICIT AND CONTAMINATION BY OIL DERIVATIVES ». Revista Árvore 41, n^o 2 (26 juin 2017). http://dx.doi.org/10.1590/1806-90882017000200005.

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ABSTRACT Accidents that occur during the transport of oil and its derivatives have been one of the primary causes of environmental pollution in recent decades. Studies on changes in plant physiology caused by these pollutants are scarce, and the effects on plant metabolism are little known. As such, the aim of the present study was to analyze the effect of soil contaminated with diesel fuel on the physiology of young Hymenaea courbaril L. and Jatropha curcas L. plants. The following variables were analyzed: gas exchanges, photosynthetic pigments, chlorophyll index (SPAD) and protoplasmic damage. The treatments used were: T0 - control (100% of maximum soil water holding capacity - contamination-free soil), T1 and T2 (50% of maximum soil water holding capacity + addition of 23 mL and 46 mL of diesel fuel, respectively) and two assessment times (3h and 192h after contamination). Significant differences in gas exchanges were observed for both species 3h after diesel fuel application. For photosynthetic pigments and the chlorophyll index, increases were found 3h and 192 h after imposed stress, for both species. A significant rise in electrolyte leakage was observed, more pronounced in J. curcas plants after 192h, for treatments T1 and T2 compared to T0. These findings show the potential of species to acclimate themselves to adverse conditions, and should be considered in recovery programs for environments degraded by oil derivatives.

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Fang, Wei, Junhua Fang, David B. Kittelson et William F. Northrop. « An Experimental Investigation of Reactivity-Controlled Compression Ignition Combustion in a Single-Cylinder Diesel Engine Using Hydrous Ethanol ». Journal of Energy Resources Technology 137, n^o 3 (23 octobre 2014). http://dx.doi.org/10.1115/1.4028771.

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Dual-fuel reactivity-controlled compression ignition (RCCI) combustion using port injection of a less reactive fuel and early-cycle direct injection (DI) of a more reactive fuel has been shown to yield both high thermal efficiency and low NOX and soot emissions over a wide engine operating range. Conventional and alternative fuels such as gasoline, natural gas, and E85 as the lower reactivity fuel in RCCI have been studied by many researchers; however, published experimental investigations of hydrous ethanol use in RCCI are scarce. Making greater use of hydrous ethanol in internal combustion engines has the potential to dramatically improve the economics and life cycle carbon dioxide emissions of using bioethanol. In this work, an experimental investigation was conducted using 150 proof hydrous ethanol as the low reactivity fuel and commercially available diesel as the high reactivity fuel in an RCCI combustion mode at various load conditions. A modified single-cylinder diesel engine was used for the experiments. Based on previous studies on RCCI combustion by other researchers, early-cycle split-injection strategy of diesel fuel was used to create an in-cylinder fuel reactivity distribution to maintain high thermal efficiency and low NOX and soot emissions. At each load condition, timing and mass fraction of the first diesel injection was held constant, while timing of the second diesel injection was swept over a range where stable combustion could be maintained. Since hydrous ethanol is highly resistant to auto-ignition and has large heat of vaporization, intake air heating was needed to obtain stable operations of the engine. The study shows that 150 proof hydrous ethanol can be used as the low reactivity fuel in RCCI through 8.6 bar indicated mean effective pressure (IMEP) and with ethanol energy fraction up to 75% while achieving simultaneously low levels of NOX and soot emissions. With increasing engine load, less intake heating is needed and exhaust gas recirculation (EGR) is required to maintain low NOX emissions.

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Liang, Zhirong, Yuejian Chen, Haoye Liu, Chongming Wang et Longfei Chen. « Characterizing combustion performance and PM emissions of an aviation compression ignition engine by fueling RP-3 kerosene and RP-3/pentanol blends ». International Journal of Engine Research, 17 mars 2022, 146808742210863. http://dx.doi.org/10.1177/14680874221086385.

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General aviation (GA) aircraft generally driven by aviation piston engines (APE) are currently experiencing promising growth globally. To relieve the fossil fuel scarce, the application of alternative fuels was extensively encouraged for green GA development. This study aims to investigate the suitability of using aviation kerosene rocket propellant 3 (RP-3) and its pentanol blends (by 30% volume fraction) in an aviation compression ignition (CI) engine, by comparing their combustion performance and emission characteristics differences under various injection timings with baseline diesel. The major combustion parameters including the in-cylinder pressure, heat release rate, ignition delay, combustion duration, indicated thermal efficiency (ITE), and indicated specific fuel consumption (ISFC) were evaluated as the crank angle (CA) 50 swept from 9 to 15° crank angle after top dead center (ATDC). The ITE of RP-3/Pentanol blends presented to be higher than those of diesel by 4.2%−5.0%, and pure RP-3 by 2.6%−3.4%. The improved ITE of the blended fuel is due to the longest ignition delay and the shortest combustion duration under all the CA50. Moreover, the particulate matter (PM) emissions with the number concentration, geometric mean diameter (GMD), size-resolved distribution characteristics were quantitatively analyzed for all the test fuels. RP-3/Pentanol dramatically reduced the number-based PM, by over 50% and two magnitudes of order lower than those of RP-3 and diesel, respectively. Improved PM emissions from the alcohol blends intensively was caused by the better premixing and evaporating states with subsequent homogeneous combustion. Additionally, the PM emissions of the three fuels exhibited different sensitivities to the varied injection timings. With the retardance of injection timings, the PM declined apparently for diesel and RP-3 due to prolonged ignition delay and decreased in-cylinder temperature, but remained nearly unchanged for RP-3/Pentanol because of the growth of nucleation mode PM.

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« “Synthesis and Performance Analysis of Acetylene for Dual Fuel Mode using S.I Engine” ». International Journal of Innovative Technology and Exploring Engineering 8, n^o 11 (10 septembre 2019) : 1020–25. http://dx.doi.org/10.35940/ijitee.i8438.0981119.

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From the reference of past few decades it is believed that crude oil petroleum products are becoming scarce and very costly. As technology is advancing fuel economy of engine is getting improved and will continue to Improve.Also, there is an enormous increase in variety of vehicles which has started dictating the demand for fuel. Gasoline and diesel will become scarce and very expensive in near future. With the increased use and depletion of fossil fuels, there is an almost need to find an alternative fuel, so that some of the problems can be minimized. An effort has been made to use an alternate fuel in 4-stroke spark ignition engine. Another reason motivating the development of an alternate fuel for an S.I engine is the concern over the emission problems of use of gasoline. Combined with the other air polluting systems the large no. of automobiles is a major contributor to the air quality problems of the world. The engine used for alternate fuel is a modified S.I engine, which was originally designed for petrol fuelling. An extensive research and development is done by using acetylene as an alternative fuel which is a gas, obtained from combination of calcium carbide and water. For this, particular storage gas cylinder is designed with certain mechanical elements. Maximum performance and investigation for obtaining the efficiencies can be done using this alternative fuel and hence analysis based on performance is carried out. Also Comparison study of petrol and acetylene, CNG and acetylene is accomplished.

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Ikeh, C. U. « Solar Energy as an Alternative for an All Year Round Production of Vegetables in Anambra, Nigeria ». Journal of Energy Research and Reviews, 23 mars 2019, 1–5. http://dx.doi.org/10.9734/jenrr/2019/v2i330079.

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Epileptic power supply is a major problem in Nigeria and one of the ways Nigerians have solving this challenge is by using renewable energy as an alternative power supply in place fossil fuels. Among renewable energy sources, solar is the most important because it is available in this part of the world. This energy source is also used in various industries including agriculture and it can be used in irrigation and sprinklers in farmer’s vegetable farm. This research was carried out through field visitations and extensive literature on the performance of photovoltaic modules. This paper outlines the use of solar water pump for irrigation in vegetable farms, the benefits and concludes with suggested recommendations which can help production of vegetables during dry season in Anambra State. It aims at contributing a better understanding of the potential impact of solar photovoltaic (PV) on sustainable production of vegetables with special attention to the effect of income generating activities in the State. It is known that during dry season, vegetables do not get enough water, sometimes these agricultural products are very scarce and expensive. Solar photovoltaic water pumping is found to be economically viable in comparison to electricity or diesel based systems for irrigation and sprinklers in the vegetable farm. Solar photovoltaic water pumping is therefore, an attractive alternative for irrigation and sprinklers in Nigerian vegetable farm due to the huge solar potential in the country.

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Dingemanse, Johannes Dirk, Muse Abayneh Abiyu, Kirubel Getachew Tesfaye et Feyera Fekadu Roro. « Using student science to identify research priority areas for air pollution in a university environment : an Ethiopian case study ». Clean Air Journal 32, n^o 2 (14 octobre 2022). http://dx.doi.org/10.17159/caj/2022/32/2.13470.

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Students in a country like Ethiopia face a double air pollution challenge: they are frequently exposed (both outdoors and indoors) to sources of incomplete combustion and therefore to unhealthy concentrations of particulate matter (PM2.5) and carbon monoxide (CO), while they also face increased carbon dioxide (CO2) concentrations in crowded dormitories and classrooms. Research on air pollution in the environment of Ethiopian students is scarce. This lack of research can be fixed by involving students in science through a student science project, essentially a subset of citizen science. Students of Arba Minch University, Ethiopia, conducted measurements of PM2.5, CO, and CO2 under self-selected circumstances. Their measurements are compared to guideline values related to health effects to identify priority areas for future research. For PM2.5, students’ measurements show likely exceedances of guideline values for an inside coffee ceremony, close to open waste burning, at a bus station and close to a diesel generator. For CO, exceedances are revealed in kitchens and the visitor’s area of restaurants using biomass fuel, close to outdoor charcoal cooking and close to waste burning. For CO2, exceedances are found within student dormitories. These areas can be considered priority areas for further research. Students can conduct additional measurements to distinguish other relevant scenarios. Insight into exposure can be improved if, besides different concentrations under different circumstances, also time durations of these different circumstances are studied. The findings reveal that students themselves can be a partial solution to research and resource gaps in their context.

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Siyal, Abdul Wahab, et P. Winnie Gerbens-Leenes. « The water–energy nexus in irrigated agriculture in South Asia : Critical hotspots of irrigation water use, related energy application, and greenhouse gas emissions for wheat, rice, sugarcane, and cotton in Pakistan ». Frontiers in Water 4 (14 septembre 2022). http://dx.doi.org/10.3389/frwa.2022.941722.

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Asia has a large water scarcity problem, especially in countries depending on irrigation, limiting agricultural production, and increasing food insecurity. When water becomes scarce, it needs conveyance over longer distances or pumping from deeper groundwater stocks, requiring pumping energy, often fossil energy, emitting greenhouse gasses. This causes a trade-off between irrigation water supply and fossil energy use contributing to global warming. This research focuses on the water–energy–food nexus in irrigated agriculture to improve resource management. It uses Pakistan as its case study area and assesses water consumption, energy (EFs), and carbon footprints (CFs) associated with irrigation water supply for the major crops (wheat, rice, sugarcane, and cotton) per district. The method first assesses irrigation water volumes (surface and groundwater) per crop per district and next the energy and CO2 emissions to provide this water. Data on allocated water volumes, crop areas and pumping types were taken from governmental reports. Groundwater tables and energy data were taken from scientific publication based also on actual measurements. The research identifies unfavorable hotspots and favorable areas from a water and energy perspective. Drivers determining water consumption, EFs, and CFs related to irrigation water supply show spatial and temporal differences and include crop types, temporal crop water requirements, fractions of gravity-fed and pumped water, groundwater tables, and energy sources (diesel, electric, and solar). In Pakistan, annual irrigation supply requires 103 PJ of energy generating a CF of 11 109 kg CO2 (6% of the national CF). Diesel pumps, pumping shallow groundwater, contribute most (73%), followed by electric pumps pumping deep groundwater. Energy for surface water pumping is negligible. Wheat contributes 31% to the EF, cotton 27%, and sugarcane and rice 21% each. CFs, caused by fossil energy use to pump irrigation water, are also dominated by wheat (32%) and cotton (31%), followed by rice and sugarcane (19% each). Ten hotspot districts contribute 42% to the EF of the major crops and increased by 21% in fourteen years. Wheat and cotton in Punjab and rice and cotton in Sindh are the most energy-intensive. EFs range between 3,500 and 5,000 TJ per district, with some districts in Punjab, the most important agricultural province, using even more. Large differences occur among EFs per unit of irrigation water, ranging between 7 and 2,260 KJ/m3, CFs between 1 and 444 g CO2/m3. The identification of hotspots may contribute to measures to minimize water consumption, EFs and CFs for agriculture in Pakistan. Other countries that also rely on irrigation could apply methods applied here to identify hotspots.

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Morici, Giuseppe, Fabio Cibella, Annalisa Cogo, Paolo Palange et Maria R. Bonsignore. « Respiratory Effects of Exposure to Traffic-Related Air Pollutants During Exercise ». Frontiers in Public Health 8 (11 décembre 2020). http://dx.doi.org/10.3389/fpubh.2020.575137.

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Traffic-related air pollution (TRAP) is increasing worldwide. Habitual physical activity is known to prevent cardiorespiratory diseases and mortality, but whether exposure to TRAP during exercise affects respiratory health is still uncertain. Exercise causes inflammatory changes in the airways, and its interaction with the effects of TRAP or ozone might be detrimental, for both athletes exercising outdoor and urban active commuters. In this Mini-Review, we summarize the literature on the effects of exposure to TRAP and/or ozone during exercise on lung function, respiratory symptoms, performance, and biomarkers. Ozone negatively affected pulmonary function after exercise, especially after combined exposure to ozone and diesel exhaust (DE). Spirometric changes after exercise during exposure to particulate matter and ultrafine particles suggest a decrease in lung function, especially in patients with chronic obstructive pulmonary disease. Ozone frequently caused respiratory symptoms during exercise. Women showed decreased exercise performance and higher symptom prevalence than men during TRAP exposure. However, performance was analyzed in few studies. To date, research has not identified reliable biomarkers of TRAP-related lung damage useful for monitoring athletes' health, except in scarce studies on airway cells obtained by induced sputum or bronchoalveolar lavage. In conclusion, despite partly counteracted by the positive effects of habitual exercise, the negative effects of TRAP exposure to pollutants during exercise are hard to assess: outdoor exercise is a complex model, for multiple and variable exposures to air pollutants and pollutant concentrations. Further studies are needed to identify pollutant and/or time thresholds for performing safe outdoor exercise in cities.

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Burke, Richard D. « A Numerical Study of the Benefits of Electrically Assisted Boosting Systems ». Journal of Engineering for Gas Turbines and Power 138, n^o 9 (5 avril 2016). http://dx.doi.org/10.1115/1.4032764.

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An electric compressor and an electrically assisted turbocharger have been applied to a 2.0 L gasoline and a 2.2 L diesel engine 1D wave dynamic model. A novel approach is presented for evaluating transient response using swept frequency sine wave functions and Fourier transforms. The maximum electrical power was limited to 6% of the maximum engine power (12 kW and 5 kW, respectively). The systems were evaluated under steady-state and transient conditions. Steady-state simulations showed improved brake mean effective pressure (BMEP) at low-engine speeds (below 2500 rpm) but electric power demand was lower (3 kW versus 8 kW) when the electric compressor was on the high-pressure side of the turbocharger. This was due to the surge limitation of the turbocharger compressor. The electrically assisted turbocharger offered little opportunity to increase low-speed BMEP as it was constrained by compressor map width. Rematching the turbo could address this but also compromise high-engine speeds. BMEP frequency analysis was conducted in the region of 0.01–2 Hz. This was repeated at fixed engine speeds between 1000 rpm and 2000 rpm. Spectral analysis of the simulated response showed that the nonassisted turbocharger could not follow the target for frequencies above 0.1 Hz, whereas the electrically assisted device showed no appreciable drop in performance. When assessing the electric power consumption with the excitation frequency, a linear trend was observed at engine speeds below 1500 rpm but more complex behavior was apparent above this speed where BMEP levels are high but exhaust energy was scarce.

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Brüggeshemke, Jonas, Marco Drung, Franz Löffler et Thomas Fartmann. « Effects of local climate and habitat heterogeneity on breeding-bird assemblages of semi-natural grasslands ». Journal of Ornithology, 14 mars 2022. http://dx.doi.org/10.1007/s10336-022-01972-7.

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AbstractThe intensification of agricultural land-use, abandonment and afforestation have caused severe loss and degradation of nutrient-poor, semi-natural grasslands across Europe. Calcareous grasslands have an outstanding value for nature conservation due to their highly diverse flora and fauna, including birds. However, knowledge of environmental factors driving the composition of bird communities in calcareous grasslands is still scarce. The aim of our study was to compare the breeding-bird assemblages of calcareous grasslands and the second most common semi-natural grassland type in the study area (Diemel Valley, Central Germany), mesic grasslands, along an elevation (climate) gradient. For each grassland type, we randomly selected 27 square-shaped plots with a size of 5 ha each and a cover of the focal grassland type of at least 50% within the plot. Our study revealed that both the number and density of threatened species of breeding birds were higher in plots of calcareous grasslands than in those of mesic grasslands. Based on multivariable generalised linear mixed-effects models, the most important predictors of overall species richness and density of breeding birds in plots of calcareous grasslands were the area of juniper-rich calcareous grassland and Shannon habitat diversity. By contrast, the number and density of threatened species were in both grassland types mainly driven by breeding-season temperature. Heterogeneous, juniper-rich calcareous grasslands seem to be a key habitat for bird assemblages with high species richness and density. These grasslands usually consisted of small-scale habitat mosaics providing suitable nesting sites and foraging grounds in close proximity. By contrast, mesic grasslands had rather homogeneous swards and shrubs or trees were normally restricted to the edges of the grassland patches. Based on our study, increasing habitat heterogeneity at the landscape scale and within grasslands is the key to enhancing species richness and density of breeding birds.

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Spittka, Eva, Vivien Benert, Matthias Wagner et Stephanie Fiechtner. « Wie viel Schweiz steckt im Schweizer Fernsehen ? Eine Analyse struktureller und inhaltlicher Bezüge im Fernsehprogrammangebot der SRG SSR ». Studies in Communication Sciences, 22 mars 2022. http://dx.doi.org/10.24434/j.scoms.2022.02.004.

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No Billag – in der Schweiz ist die Debatte um die Notwendigkeit und Finanzierbarkeit des öffentlich-rechtlichen Rundfunks neu entbrannt. Eng damit verbunden sind die Fragen nach dem Public Value der SRG SSR und dem Aspekt, wie viel Schweiz tatsächlich im Schweizer Fernsehen steckt. Basierend auf einer inhaltsanalytischen Sekundäranalyse der Stichprobe aus dem Jahr 2017 der kontinuierlichen Fernsehprogrammforschung in der Schweiz, wird in diesem Beitrag die Darstellung der Schweiz und des Schweizer Volkes in Bezug auf einerseits die Repräsentation in den Fernsehprogrammen der SRG SSR und andererseits hinsichtlich der Verantwortung der Medienproduktion diskutiert. Die Ergebnisse zeigen, dass die Schweiz in informierenden Genres (z. B. Nachrichten) eine wichtige Rolle spielt, während in fiktionalen Inhalten (z. B. Serien, Filmen) nur selten auf die Schweiz Bezug genommen wird. Hinzu kommt, dass fiktionale Inhalte der SRG SSR häufig von internationalen Produktionsfirmen, insbesondere aus den grossen Nachbarländern der Schweiz, verantwortet werden. No Billag – in Switzerland, the debate about the necessity and financial viability of public broadcasting has been sparked anew. Closely linked are questions about the public value of the SRG SSR and how much of Switzerland is actually portrayed on Swiss television. Based on a secondary analysis of the 2017 data set of the continuous Swiss content analysis study, this paper discusses the representation of Switzerland and the Swiss people in terms of representation in television programmes of the SRG SSR and in terms of media production. Results show that Switzerland plays an important role in informational genres (e. g., News), while in fictional content (e. g., series, movies) references to Switzerland are scarce. Additionally, fictional content broadcast by the SRG SSR is often produced by international production firms, with preferences for content from Switzerland’s next-door-giant neighbours.

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Jabbour, Naim. « Energy Production and Consumption Patterns : An Examination of the State of Energy, Electricity, and Air Pollution in Lebanon ». Journal of Architectural Design and Construction Technology 1, n^o 1 (19 mai 2020). http://dx.doi.org/10.47890/jadct/2020/njabbour/10123454.

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Natural resources including energy are very scarce in Lebanon. As such, the country imports more than 90% of the fuel to satisfy its energy and electricity needs (EIA), primarily fossil fuel based. Furthermore, fuel consumption is forecasted to grow over the next decade, exacerbating the reliance on foreign volatile energy sources. This paper provides an overview of the energy sector in Lebanon and its impact on air pollution. Similarly, population growth is expected to continue on a steady and consistent rate, while resources remain limited. To that end, electricity consumption is disproportionate to population growth, indicative of severe inefficiencies and waste. Furthermore, the total energy consumption per household in Lebanon far exceeded its counterparts in the EU and the US. The country’s energy production market is severely volatile and unreliable, resulting in only a 50-70% coverage of electrical needs from public governmental sources. Consequently, current public electric generation capacity is not meeting con-sumption patterns, resulting in widespread power outages, blackouts, and a heavy reliance on the unregulated” mafia-like” private generation market. Furthermore, energy consumption patterns have been increasing over the past decade and are projected to continue to grow over the next 10 years. Correspondingly, emissions patterns follow a similar trend to energy consumption pat-terns. As a result, the World Health Organization (WHO) estimated a 100% of the population is exposed to pollution levels above the recommended guidelines. Moreover, governmental failure to regulate and protect the environment has severely impacted the country’s natural resources and overall environment. As such, Lebanon was ranked 5th in the 2019 Pollution Index for Country, which examined air pollution in countries worldwide. The World Health Organization estimates the levels of air pollution in Leb-anon to be at a tipping point. Furthermore, air pollution is considered the greatest threat towards the health of Lebanese citizens. The proliferation of the transportation sector, unregulated energy sector, and private diesel generators are major contributors to air pollution in the beleaguered nation. To that end, the residential sector constituted a major contributor to this pollution, account-ing for more than 30% of total energy use in the country and its associated emissions. Most of this energy is provided via liquified petroleum gas (LPG) generated electricity, a major fossil fuel. This paper explores the state of energy and electricity in Lebanon and their implications on air pollution. It also examines the state of energy use within the residential sector as it relates to overall electricity and pollution patterns. Lastly, the paper provides a sampling of alternative solutions and mechanisms to combat the electricity crisis and air pollution problems. Keywords: Energy Consumption; Electricity Generation; Residential Energy Patterns; Air Pollution

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