scholarly journals Study of Biocrudes Obtained via Hydrothermal Liquefaction (HTL) of Wild Alga Consortium under Different Conditions

Processes ◽  
2021 ◽  
Vol 9 (9) ◽  
pp. 1494
Author(s):  
Caroline Barrère-Mangote ◽  
Anne Roubaud ◽  
Brice Bouyssiere ◽  
Julien Maillard ◽  
Jasmine Hertzog ◽  
...  
Keyword(s):  
Global Warming ◽  
Fossil Fuels ◽  
Culture Medium ◽  
Matter Content ◽  
Hydrothermal Liquefaction ◽  
Mineral Matter ◽  
Harsh Environment ◽  
Industrial Environment ◽  
Plant Emissions ◽  
Heavy Fractions

Microalga-based fuels are promising solutions for replacing fossil fuels. This feedstock presents several advantages such as fast growth in a harsh environment and an ability to trap gases emitted from industries, thus reducing global warming effects. An efficient way to convert harvested microalgae into biofuels is hydrothermal liquefaction (HTL), which yields an intermediate product called biocrude. In this study, the elemental and molecular compositions of 15 different HTL biocrudes were determined by means of different techniques. Wild algae were cultivated in an industrial environment with plant emissions as a carbon source in fresh or seawater. It was notably observed that the culture medium had an influence on the biochemical composition and mineral matter content of algae. Thus, seawater algae were characterized by larger amounts of carbohydrates and mineral matter than freshwater ones, which also affected the oil yields and the light and heavy fractions of biocrudes.

Global Warming and Its Multiple Causes

2020 ◽  
Vol 3 (2) ◽  
Author(s):  
Romdhane Ben Slama
Keyword(s):  
Global Warming ◽  
Greenhouse Gases ◽  
Greenhouse Effect ◽  
Infrared Radiation ◽  
Fossil Fuels ◽  
Ambient Air ◽  
The Earth ◽  
The One ◽  
Heat Released ◽  
Emission Of Greenhouse Gases

The global warming which preoccupies humanity, is still considered to be linked to a single cause which is the emission of greenhouse gases, CO2 in particular. In this article, we try to show that, on the one hand, the greenhouse effect (the radiative imprisonment to use the scientific term) took place in conjunction with the infrared radiation emitted by the earth. The surplus of CO2 due to the combustion of fossil fuels, but also the surplus of infrared emissions from artificialized soils contribute together or each separately,  to the imbalance of the natural greenhouse effect and the trend of global warming. In addition, another actor acting directly and instantaneously on the warming of the ambient air is the heat released by fossil fuels estimated at 17415.1010 kWh / year inducing a rise in temperature of 0.122 ° C, or 12.2 ° C / century.

scholarly journals Prediction of metabolizable energy values in poultry offal meal for broiler chickens

2010 ◽  
Vol 39 (10) ◽  
pp. 2237-2245 ◽  
Author(s):  
Edney Pereira da Silva ◽  
Carlos Bôa-Viagem Rabello ◽  
Luiz Fernando Teixeira Albino ◽  
Jorge Victor Ludke ◽  
Michele Bernardino de Lima ◽  
...  
Keyword(s):  
Chemical Composition ◽  
Broiler Chickens ◽  
Crude Protein ◽  
Matter Content ◽  
Metabolizable Energy ◽  
Mineral Matter ◽  
Ether Extract ◽  
High Fat ◽  
Collection Method ◽  
Gross Energy

This research aimed at generating and evaluating prediction equations to estimate metabolizable energy values in poultry offal meal. The used information refers to values of apparent and true metabolizable energy corrected for nitrogen balance (AMEn and TMEn) and for chemical composition of poultry offal meal. The literature review only included published papers on poultry offal meal developed in Brazil, and that had AMEn and TMEn values obtained by the total excreta collection method from growing broiler chickens and the chemical composition in crude protein (CP), ether extract (EE), mineral matter (MM), gross energy (GE), calcium (Ca) and phosphorus (P). The general equation obtained to estimate AMEn values of poultry offal meal was: AMEn = -2315.69 + 31.4439(CP) + 29.7697(MM) + 0.7689(GE) - 49.3611(Ca), R² = 72%. For meals with high fat contents (higher than 15%) and low mineral matter contents (lower than 10%), it is suggest the use of the equation AMEn = + 3245.07 + 46.8428(EE), R² = 76%, and for meals with high mineral matter content (higher than 10%), it is suggest the equations AMEn = 4059.15 - 440.397(P), R² = 82%. To estimate values of TMEn, it is suggested for meals with high mineral matter content the equation: TMEn = 5092.57 - 115.647(MM), R² = 78%, and for those with low contents of this component, the option is the equation: TMEn = 3617.83 - 15.7988(CP) - 18.2323(EE) - 96.3884(MM) + 0.4874(GE), R² = 76%.

Microstructure and composition of the periderm of conulariids

2016 ◽  
Vol 90 (3) ◽  
pp. 389-399 ◽  
Author(s):  
Robert C. Ford ◽  
Heyo Van Iten ◽  
George R. Clark
Keyword(s):  
Organic Matter ◽  
Organic Matter Content ◽  
Matter Content ◽  
Mineral Matter ◽  
Upper Ordovician ◽  
The Core ◽  
Critical Point Drying ◽  
Thin Walled ◽  
Electron Imaging ◽  
Aperture Closure

AbstractTransmitted light and scanning electron imaging of sectioned specimens ofConulariaandParaconularia, prepared using HCl etching and critical point drying, revealed that their periderm is composed of extremely thin (approximately 0.5–3 µm), variably distinct microlamellae that are alternately organic poor and organic rich. Organic-rich microlamellae are cross-connected by slender strands of organic matter originally embedded in calcium phosphate, which in etched specimens has been dissolved. Microlamellae may be organized in thicker (approximately 5–75 µm) layers, or macrolamellae, that vary in color and organic matter content, possibly owing to changes in the ambient paleoenvironment. Thickening of the periderm to form transverse ribs and internal carinae was achieved through gradual thickening of individual microlamellae. In the core of the transverse ribs and internal carinae the distinction between organic-rich and organic-poor microlamellae may be reduced, owing to organic material becoming dominant over (former) mineral matter or vice versa. Combined with observations of plicated aperture closure in thin-walled conulariids, includingArchaeoconularia slateri(Reed, 1933) (Upper Ordovician, Scotland) showing smooth folding of midline carinae through angles greater than 90°, these results suggest a structure and original flexibility in the organic-rich biocomposite forming the conulariid periderm that supports its homology to the chitinous lamellar periderm of coronate scyphozoans.

Effect of Co, Cu, and Zn on FeAlK catalyst in CO2 hydrogenation to C5+ hydrocarbons

2022 ◽  
Author(s):  
Khasan Nasriddinov ◽  
Ji-Eun Min ◽  
Hae-Gu Park ◽  
Seung Ju Han ◽  
Jingyu Chen ◽  
...  
Keyword(s):  
Global Warming ◽  
Catalytic Activity ◽  
Fossil Fuels ◽  
Co2 Hydrogenation ◽  
High Catalytic Activity ◽  
Long Chain ◽  
Cu And Zn

Direct CO2 hydrogenation to long-chain hydrocarbons can mitigate global warming by extensively replacing fossil fuels. However, designing a suitable catalyst with high catalytic activity and C5+ hydrocarbon selectivity continues to...

scholarly journals The Race of Mankind: Global Warming In the 21rst Century

2016 ◽  
Vol 4 (2) ◽  
pp. 1 ◽  
Author(s):  
Jan Erik Lane
Keyword(s):  
Climate Change ◽  
Global Warming ◽  
Policy Implementation ◽  
Third World ◽  
Fossil Fuels ◽  
Implementation Process ◽  
Financial Assistance ◽  
The Third ◽  
The Third World ◽  
First World

The implementation process of the global accord on climate change has to start now in order to be implementable. The decentralized process if implementation should take the lessons from the theory of policy implementation into account (Pressman & Wildavsky, 1984; Wildavsky, 1987). The dependency upon various forms of coal (wood, stone) and fossil fuels is so large in the Third World that only massive financial assistance from the First World can mean a difference for the COP21 objectives. And many advanced countries (except Uruguay) also need to make great changes to comply with COP21.

scholarly journals Effect of sheep grazing on mineral matter content of steppe stands in national nature reserve Mohelská serpentinite steppe

2005 ◽  
Vol 53 (5) ◽  
pp. 159-168
Author(s):  
Pavel Veselý
Keyword(s):  
Dry Matter ◽  
Nature Reserve ◽  
Matter Content ◽  
Mineral Matter ◽  
Serpentine Soils ◽  
Sheep Grazing ◽  
Merino Sheep ◽  
National Nature Reserve ◽  
Pasture Area ◽  
Vegetative Season

The aim of the study was to evaluate the effect of sheep pasture on the content of minerals in growth of the Mohelenska Serpentine Steppe National Nature Reserve.Merino sheep pastured on the steppe in 1997–1998, electrical fencer was used. There were 6.8–9.4 sheep per 1 ha in 1997 and 6.7–8.7 sheep per 1 ha in 1998 on the pasture area 4.25 and 6 ha. Samples of steppe growth were taken from five locations with typical fytocenological composition for particular area of steppe. Samples were taken each two weeks during vegetative season from area 3x1 m2. The contents of Ca, P, Na, K, Mg, Mn, Zn, Cu and Fe in dry matter were evaluated. The changes in the content of the nutrients were evaluated depending on the location before, after and during pasture. The values of nutrients were compared with content of these nutrients in meadow and pasture growths (noted in European databases).The content of Ca was from 2.23 to 4.06 g/kg of dry matter. Pasture decreased the variability of location in Ca content and there were significant decreases of Ca content on two locations (P < 0.01). Low content of Ca in steppe growth due to pasture significantly decreased on these locations in comparison with Ca content in pasture growth on no-serpentine soil. The content of P was from 2.23 to 4.06 g/kg of dry matter. Pasture did not affect the variability of location and on one location pasture significantly increased its content (P < 0.01). Despite it the content of P in dry matter was markedly lower than in pasture growths.The content of Na was from 43.88 to 113.97 mg/kg of dry matter. Pasture did not affect the variability of location and its content. The content of Na was markedly lower in steppe growth in comparison with pasture growths. Pasture also did not affect the content of K, which was from 9.96 to 18.10 g/kg of dry matter. But pasture increased the variability of location. The content of K in steppe growth was low in comparison with pasture growths. The content of Mg was from 2.14 to 4.64 g/kg of dry matter. On two locations the content of Mg increased due to pasture (P < 0.05). The content of Mg in steppe growth was comparable with its content in pasture growths. The content of Mn was from 27.55 to 41.32 mg/kg of dry matter and the content of Zn from 12.05 to 26.64 mg/kg of dry matter. Pasture increased the variability of location in both these nutrients. The effect of the pasture on their contents was not (P < 0.05). In steppe growth the content of Mn was markedly lower in comparison with pasture growths and the content of Zn was lower in comparison with pasture growths. The contents of Cu and Fe were from 1.81 to 5.94 mg/kg of dry matter and from 76.1 to 263.2 mg/kg of dry matter. Pasture increased variability of location in the content of Cu and decreased its content in three locations (P < 0.05). The content of Fe was not affected by pasture (P < 0.05). The contents of Cu and Fe were lower in comparison with pasture growths on no-serpentine soils.

scholarly journals Subcritical and Supercritical Operation of Innovative Thermal Mechanical Refrigeration System

2020 ◽  
Author(s):  
Ahmad Sleiti ◽  
Wahib Al-Ammari ◽  
Mohammed Al-Khawaja ◽  
Maxim Glushenkov ◽  
Alexander Kronberg
Keyword(s):  
Global Warming ◽  
Ozone Depletion ◽  
Fossil Fuels ◽  
Waste Heat ◽  
Low Frequency ◽  
Low Grade ◽  
Refrigeration System ◽  
Heat System ◽  
Global Warming Potentials ◽  
Carbon Dioxide Co2

Around 17% of the globally generated energy is consumed for residential, commercial, and transportation refrigeration. The current cooling technologies utilize refrigerants with high Ozone Depletion and Global Warming Potentials. Furthermore, the current technologies are expensive alongside with toxicity and flammability hazards. On the other side, energy produced by combustion of fossil fuels results in substantial amounts of waste heat. Therefore, it is necessary to develop new refrigeration technologies that utilize waste heat as a source of energy with ecofriendly refrigerants with zero ozone depletion potential and zero global warming potential. In addition, this thermal mechanical refrigeration (TMR) technology improves the energy efficiency of the source of waste heat system and minimizes the emissions of the carbon dioxide (CO2). In this study, a novel thermo-mechanical refrigeration system is proposed. It operates with low-grade energy sources (such as waste heat) at temperature range of 60 oC to 100 oC. Furthermore, it has the advantage of working with low-frequency driver-compressor unit, which eliminates noise and increases its lifetime. Moreover, the TMR system is adaptable to commercial, transportation, and residential refrigeration applications.

scholarly journals Environmental Payback of Renovation Strategies in a Northern Climate—the Impact of Nuclear Power and Fossil Fuels in the Electricity Supply

Energies ◽  
2019 ◽  
Vol 13 (1) ◽  
pp. 80 ◽  
Author(s):  
Ricardo Ramírez-Villegas ◽  
Ola Eriksson ◽  
Thomas Olofsson
Keyword(s):  
European Union ◽  
Energy Efficiency ◽  
Global Warming ◽  
Life Cycle ◽  
Radioactive Waste ◽  
Global Warming Potential ◽  
Nuclear Power ◽  
Fossil Fuels ◽  
The European Union ◽  
The Impact

The aim of this study is to assess how the use of fossil and nuclear power in different renovation scenarios affects the environmental impacts of a multi-family dwelling in Sweden, and how changes in the electricity production with different energy carriers affect the environmental impact. In line with the Paris Agreement, the European Union has set an agenda to reduce greenhouse gas emissions by means of energy efficiency in buildings. It is estimated that by the year 2050, 80% of Europe’s population will be living in buildings that already exist. This means it is important for the European Union to renovate buildings to improve energy efficiency. In this study, eight renovation scenarios, using six different Northern European electricity mixes, were analyzed using the standard of the European Committee for Standardization for life cycle assessment of buildings. This study covers all life cycle steps from cradle to grave. The renovation scenarios include combinations of photovoltaics, geothermal heat pumps, heat recovery ventilation, and improvement of the building envelope. The results show that while in some electricity mixes a reduction in the global warming potential can be achieved, it can be at the expense of an increase in radioactive waste production, and, in mixes with a high share of fossil fuels, the global warming potential of the scenarios increases with time, compared with that of the original building. It also shows that in most electricity mixes, scenarios that reduce the active heat demand of the building end up in reducing both the global warming potential and radioactive waste, making them less sensitive to changes in the energy system.

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