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Author(s):  
Manoel Raimundo dos Santos Jr. ◽  
Elinéia Castro Costa ◽  
Caio Campos Ferreira ◽  
Lucas Pinto Bernar ◽  
Marcilene Paiva da Silva ◽  
...  

In this work, the deoxygenation of organic liquid products (OLP) obtained by thermal catalytic cracking of palm oil at 450 °C, 1.0 atmosphere, with 10% (wt.) Na2CO3 as catalyst, in multistage countercurrent absorber columns using supercritical carbon dioxide (SC-CO2) as solvent, with Aspen-HYSYS process simulator was systematically investigated. In a previous study, the thermodynamic data basis and EOS modeling necessary to simulate the deoxygenation of OLP has been presented [Molecules 2021, 26, 4382. https://doi.org/10.3390/molecules26144382]. This work address a new flowsheet, consisting of 03 absorber columns, 10 expansions valves, 10 flash drums, 08 heat exchanges, 01 pressure pump, and 02 make-up of CO2, aiming to improve the deacidification of OLP. The simulation was performed at 333 K, 140 bar, and (S/F) = 17; 350 K, 140 bar, and (S/F) = 38; 333 K, 140 bar, and (S/F) = 25. The simulation shows that 81.49% of OLP could be recovered and the concentrations of hydrocarbons in the extracts of absorber-01 and absorber-02 were 96.95 and 92.78% (wt.) in solvent-free basis, while the bottom stream of absorber-03 was enriched in oxygenates compounds with concentrations up to 32.66% (wt.) in solvent-free basis, showing that organic liquid products (OLP) was deacidified and SC-CO2 was able to deacidify OLP and to obtain fractions with lower olefins content. The best deacidifying conditions was obtained at 333 K, 140 bar, and (S/F) = 17.


Energies ◽  
2021 ◽  
Vol 14 (9) ◽  
pp. 2399
Author(s):  
Barbara Malsegna ◽  
Andrea Di Giuliano ◽  
Katia Gallucci

This paper aims to investigate the usage of waste from Absorbent Hygienic Products (AHP) as a fuel for gasification or pyrolysis, two attractive routes to obtain valuable products and dispose of this kind of waste. The study experimentally investigated the devolatilization of coarsely shredded materials from diapers, in a laboratory-scale bubbling fluidized bed made of sand, as a representative preparatory step of the above-mentioned thermochemical conversions. Two versions of shredded materials were considered: as-manufactured diapers (AHPam, as a reference), and the cellulosic fraction of sterilized used diapers (AHPus). Results were presented, obtained from physical-chemical characterization of AHPam and AHPus (TGA, CHNS/O, proximate and ultimate analyses, XRF, ICP-AES, SEM-EDS), as well as from their devolatilizations at 500–600–700–800 °C under two different atmospheres (air plus nitrogen, or pure nitrogen as a reference). Generally, temperature influenced syngas composition the most, with better performances under pure nitrogen. At 700–800 °C under pure nitrogen, the highest syngas quality and yield were obtained. For AHPam and AHPus, respectively: (i) H2 equaled 29.5 vol% and 23.7 vol%, while hydrocarbons equaled 14.8 vol% and 7.4 vol% on dry, dilution-free basis; (ii) 53.7 Nl and 46.0 Nl of syngas were produced, per 100 g of fuel. Overall, AHP emerged as an interesting fuel for thermochemical conversions.


2021 ◽  
Vol Volume 13, issue 1 ◽  
Author(s):  
Sebastià Mijares ◽  
Enric Ventura

An extension of subgroups $H\leqslant K\leqslant F_A$ of the free group of rank $|A|=r\geqslant 2$ is called onto when, for every ambient free basis $A'$, the Stallings graph $\Gamma_{A'}(K)$ is a quotient of $\Gamma_{A'}(H)$. Algebraic extensions are onto and the converse implication was conjectured by Miasnikov-Ventura-Weil, and resolved in the negative, first by Parzanchevski-Puder for rank $r=2$, and recently by Kolodner for general rank. In this note we study properties of this new type of extension among free groups (as well as the fully onto variant), and investigate their corresponding closure operators. Interestingly, the natural attempt for a dual notion -- into extensions -- becomes trivial, making a Takahasi type theorem not possible in this setting.


Author(s):  
Barbara Malsegna ◽  
Andrea Di Giuliano ◽  
Katia Gallucci

This paper aims to investigate the usage of waste from Absorbent Hygienic Products (AHP) as a fuel for gasification or pyrolysis, two attractive routes to obtain valuable products and dispose of this kind of waste. The study experimentally investigated the devolatilization of coarsely shred-ded materials from diapers, in a laboratory-scale bubbling fluidized bed made of sand, as a rep-resentative preparatory step of above-mentioned thermochemical conversions. Two versions of shredded materials were considered: as-manufactured diapers (AHPam, as a reference), and the cellulosic fraction of sterilized used diapers (AHPus). Results were presented, obtained from physic-chemical characterization of AHPam and AHPus (TGA, CHNS/O, proximate and ultimate analysis, XRF, ICP-AES, SEM-EDS) and their devolatilizations at 500-600-700-800°C, under two different atmospheres (air plus nitrogen, or pure nitrogen as a reference). Generally, temperature had most influenced syngas composition, with better performances under pure nitrogen. At 700-800 °C under pure nitrogen, the highest syngas quality and yield were obtained. For AHPam and AHPus, respectively: (i) H2 richness equaled 29.5 vol% and 23.7 vol%, while hydrocarbons poorness equaled 14.8 vol% and 7.4 vol% on dry, dilution-free basis; (ii) 53.7 Nl 100 gfuel-1 and 46.0 Nl 100 gfuel-1 were produced. Overall, AHP emerged as an interesting fuel for thermochemical conversions.


2021 ◽  
Vol 75 (3) ◽  
Author(s):  
César Martínez-Flores ◽  
Michael-Adán Martínez-Sánchez ◽  
Rubicelia Vargas ◽  
Jorge Garza
Keyword(s):  

Author(s):  
S. Volodin ◽  
◽  

The article analyzes the production of potatoes in Ukraine in 2005-2019 in all categories of farms, agricultural enterprises, farms, households. The problems of the present in the development of the potato industry have been clarified. It is proposed to create an integrated scientific and innovative system of production and sale of domestic potato seeds on the basis of partnership between science and business, in particular the creation of the Innovation Cluster «Ukrainian Potatoes». The tasks of the Innovation Cluster «Ukrainian Potato» are considered. The basic positions of the project «Ukrainian potato» are given. The stages of development of the business infrastructure of the Ukrainian Potato cluster are studied. Attention is paid to the research and production network of the project and the stages of project implementation of the Innovation Cluster «Ukrainian Potato». Further directions of research of this theme are offered.


2021 ◽  
Vol 3 (1) ◽  
pp. 188-210
Author(s):  
Andrey V. Smirnov ◽  

The article is dedicated to the problem of stringing together Russian social reality and genuine theoretical concerns of philosophy. Due to lifting ideological restriction in 1991 the major part of philosophical work was aimed on catching up with Western philosophy widening the gap between society and philosophy in Russia and stating Western value system as universal. The pressing issue for modern Russian philosophy is to formulate and to accept the epis­temological basis for Russian civilization project equal in scale to the Western one. It re­quires the search of a new solution that could be able to gather heterogeneous value sys­tems of Russian society. It should be more universal than “traditional Russian values”, which requires the great efforts on developing individual philosophical consciousness and reaching the deep self-awareness both philosophical and social. The Western-free basis of cogitation in Russian culture could be found in the idea of Vsesubektnostʼ as an utopian idea of the whole world unity, non-losable entirety and non-losable subjectivity. This idea could be used as unobtainable ideal to contemplate how the big culture could manifest itself into civilization system. It specifies the huge field for all-level research from the philosophy of consciousness to the practical cultural and civilization construction.


2020 ◽  
Vol 98 (Supplement_4) ◽  
pp. 144-144
Author(s):  
Holland C Dougherty ◽  
Mark Evered ◽  
James W Oltjen ◽  
Hutton Oddy ◽  
Roger Hegarty

Abstract The nutritional effects of variation in feed supply and subsequent compensatory gain can play a significant role in cattle and beef production, due to their effects on carcass quality and feed costs. A system that predicts changes in fat and protein content of muscle and viscera in animals of different life stages and nutritional histories could therefore assist management to optimize performance and reduce costs of feed. A method has been developed to simultaneously estimate body composition and nutrient requirements of ruminants. This method estimates body composition from the difference in energy balance derived from ME intake, and heat production from ME intake and protein content of muscle and viscera, but requires information on protein content of fat free mass in viscera and non-viscera “muscle” tissue. Data from the literature was combined with unpublished data from a study conducted in growing lambs. This experiment tested the effects of ad libitum intake of diets of varying energy density and added RUP on performance and carcass composition of lambs that had been previously restricted or unrestricted prior to a 12–13 week finishing phase, and both carcass and viscera components were chemically analyzed on an individual basis. On a fat-free basis, muscle crude protein averaged 20.8%; this value is in agreement with literature values, which lie between the range of 20–24% and which do not appear to vary substantially with age in postweaning sheep. In the same sheep, crude protein content of viscera averaged 15.6% on a fat-free basis; while data on visceral composition in the literature is limited, these values are within the range of available data. This data is use to parameterize functions describing growth of viscera and changes in heat production over time. This contributes to the method we have developed to estimate nutritional effects on body composition.


Author(s):  
Oleg Soloviev

In theory of optical aberrations, an aberrated wavefront is represented by its coefficients in some orthogonal basis, for instance by Zernike polynomials. However, many wavefront measurement techniques implicitly approximate the gradient of the wavefront by the gradients of the basis functions. For a finite number of approximation terms, the transition from a basis to its gradient might introduce an aliasing error. To simplify the measurements, another set of functions, an “optimal basis” with orthogonal gradients, is often introduced, for instance Lukosz–Braat polynomials. This paper first shows that such bases do not necessarily eliminate the aliasing error and secondly considers the problem of finding an alias-free basis on example of second-moment-based indirect wavefront sensing methods. It demonstrates that for these methods any alias-free basis should be formed by functions simultaneously orthogonal in two dot-products and be composed of the eigenfunctions of the Laplace operator. The fitness of such alias-free basis for optical applications is analyzed by means of numerical simulations on typical aberrations occurring in microscopy and astronomy.


Author(s):  
Marc De Kesel

Abstract What precisely is at stake in Simone Weil’s shift to Christianity? Is it only the story of a modern agnostic intellectual discovering and reinventing an old religious tradition? What if, under the surface of that move, modernity itself is as much at stake? What if Weil’s mystical thought conceals a profound reflection on the modern subject? It is true, in line with almost the entire pre-modern and modern mystical tradition, her thought is a full-blown attack against the Cartesian ego and its pretention to be the solid and free basis of our modern relation to reality. But what if the most interesting aspect of Weil’s thought is that she fails in that attack, and that, despite all her efforts to destroy that subject, that very subject resists even in the very heart of both the mystical truth she describes and in her theoretical thought about that truth. What if Weil’s move to Christianity does not say so much about Christianity, nor about the Christian side of modernity, but about the abysmal base of modernity’s subject?


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