Constraints on the high energy source of Seyfert 1 from BeppoSAX observations

2001 ◽  
Author(s):  
P. O. Petrucci
Keyword(s):  
Nature ◽  
1996 ◽  
Vol 379 (6568) ◽  
pp. 799-801 ◽  
Author(s):  
C. Kouveliotou ◽  
J. van Paradijs ◽  
G. J. Fishman ◽  
M. S. Briggs ◽  
J. Kommers ◽  
...  

2018 ◽  
Vol 10 (9) ◽  
pp. 3254 ◽  
Author(s):  
Miguel-Angel Perea-Moreno ◽  
Francisco Manzano-Agugliaro ◽  
Quetzalcoatl Hernandez-Escobedo ◽  
Alberto-Jesus Perea-Moreno

The peanut (Arachys hypogaea) is a plant of the Fabaceae family (legumes), as are chickpeas, lentils, beans, and peas. It is originally from South America and is used mainly for culinary purposes, in confectionery products, or as a nut as well as for the production of biscuits, breads, sweets, cereals, and salads. Also, due to its high percentage of fat, peanuts are used for industrialized products such as oils, flours, inks, creams, lipsticks, etc. According to the Food and Agriculture Organization (FAO) statistical yearbook in 2016, the production of peanuts was 43,982,066 t, produced in 27,660,802 hectares. Peanuts are grown mainly in Asia, with a global production rate of 65.3%, followed by Africa with 26.2%, the Americas with 8.4%, and Oceania with 0.1%. The peanut industry is one of the main generators of agroindustrial waste (shells). This residual biomass (25–30% of the total weight) has a high energy content that is worth exploring. The main objectives of this study are, firstly, to evaluate the energy parameters of peanut shells as a possible solid biofuel applied as an energy source in residential and industrial heating installations. Secondly, different models are analysed to estimate the higher heating value (HHV) for biomass proposed by different scientists and to determine which most accurately fits the determination of this value for peanut shells. Thirdly, we evaluate the reduction in global CO2 emissions that would result from the use of peanut shells as biofuel. The obtained HHV of peanut shells (18.547 MJ/kg) is higher than other biomass sources evaluated, such as olive stones (17.884 MJ/kg) or almond shells (18.200 MJ/kg), and similar to other sources of biomass used at present for home and industrial heating applications. Different prediction models of the HHV value proposed by scientists for different types of biomass have been analysed and the one that best fits the calculation for the peanut shell has been determined. The CO2 reduction that would result from the use of peanut shells as an energy source has been evaluated in all production countries, obtaining values above 0.5 ‰ of their total emissions.


2016 ◽  
Author(s):  
Alessandro Carosi ◽  
Fabrizio Lucarelli ◽  
Lucio A. Antonelli ◽  
Paolo Giommi

2010 ◽  
Vol 132 (4) ◽  
Author(s):  
Elaine Virmond ◽  
Robson L. Schacker ◽  
Waldir Albrecht ◽  
Christine A. Althoff ◽  
Maurício de Souza ◽  
...  

The solid waste generated from the apple juice industry (apple bagasse (AB)) was characterized as a fuel, and the potential for its utilization as an alternative energy source was assessed through its combustion in a pilot scale cyclone combustor. A comparative evaluation of the AB and sawdust (SD) properties, as well as of the emissions during the combustion tests, was performed. The high energy content of AB (lower heating value (LHV) equal to 21.09 MJ kg−1), dry and ash-free (daf) basis, which is 26.9% higher than the LHV of SD (16.62 MJ kg−1, daf), and combined with the high volatile matter content (85.36 wt %, daf) improve the ignition and burning of the solids. The emissions of CO, SO2, and NOx and the total organic carbon (TOC) were compared with guideline limits established by Brazilian and international legislation. AB generated much lower CO than sawdust in spite of almost half of excess air levels (13% compared with 26%) and met even the stringent limit of the German regulation for waste incineration. The unburned carbon percentages found in the ash resulted from SD and AB combustion tests were 0.24% and 0.96% in weight, respectively. The absence of sulfur in AB composition represents an advantage with nondetectable SO2. The average level of NOx emission with SD combustion was 242 mg N m−3 and met all the regulation limits. The average NOx emission with AB combustion though was 642 mg N m−3 and met the U.S. EPA regulation but was marginally higher than the Brazilian norm by 15%. TOC concentrations remained below the limits considered even though the TOC level was higher in the AB combustion test. Polycyclic aromatic hydrocarbons (PAH) were not detected or were under the quantification limit of the equipment used in their analysis. Comparing the properties, the burning profiles of SD and AB, and the emissions from their combustion tests, it can be stated that the waste originating from the apple juice industry is suitable for direct combustion, constituting a renewable energy source for this industrial sector.


2015 ◽  
Vol 6 (2) ◽  
Author(s):  
Vladan Mićić ◽  
Pero Dugić ◽  
Zoran Petrović ◽  
Milorad Tomić

The use of fossil fuels results in global warming and pollution. In comparison with fossil fuels biofuels represent an eco-friendly, biodegradable, sustainable, cost-competitive and promising alternative energy source. They contain high energy content and do not contribute to greenhouse effect. Therefore, using cheap or renewable resources as the feedstock for biofuels production has a great potential in terms of a major contribution to future energy supply. The production and use of biofuels is already well established and a further promotion of these fuels such as lipid biofuels (bioethanol, pure plant oils and biodiesel) and gas biofuels (biomethane, biohydrogen) mainly depends on non-technical issues, such as policies and cost–effectiveness. Biofuels will definitely stay for the foreseeable future and still can continue to provide the earth and the human population with a relatively clean source of energy with several benefits such as economic benefits of providing employment and health benefits of reduced carbon emissions, leading to cleaner air. With increasing sophistication of technology and intense research and development done, one can safely infer that biofuel will become more appealing and applicable for use on a globally commercial level. As such, biofuel is acknowledged as the Earth’s future energy source. Until a newer and cleaner energy source is discovered, scientists will definitely persist in researching and enhancing biofuels to make them more cost-effective, while still being environmentally friendly.


2021 ◽  
Author(s):  
Kelly Malone ◽  
Anushka Udara Abeysekara ◽  
Andrea Albert ◽  
Ruben Alfaro ◽  
César Alvarez ◽  
...  

Author(s):  
J. Odgers ◽  
A. Coban

Details are given of a calorimetric-bomb technique used to determine the energy released to the gas, from a spark derived from a high-energy source (∼12J). The statistical nature of the energy release is commented upon, and the number of repeat tests required to obtain a valid mean is discussed. Scattered data from other sources are cited, together with their relevance to the present tests. Measurements of energy are given for the single plug which was subjected to exhaustive testing over a range of pressures from 1.0 kPa to 2500 kPa, and which was repeated for various gases, namely — air, oxygen, nitrogen, carbon dioxide, helium and argon. The results of these tests may be correlated in terms of the pressure and the ionization potential of the gas.


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