Search results for "Etre"
showing 10 items of 350 documents
Chemical Pretreatments of Wood Chips Prior to Alkaline Pulping - A Review of Pretreatment Alternatives, Chemical Aspects of the Resulting Liquors, an…
2015
The chemical industry is being forced to evaluate new strategies for more effective utilization of renewable feedstocks to diminish the use of fossil resources. In this literature review, the integration of both acidic and alkaline pretreatment phases of hardwood and softwood chips with chemical pulping is discussed. Depending on the pretreatment conditions, high-volume sulfur-free fractions with varying chemical compositions can be produced. In case of acidic pretreatments, the major products include carbohydrates (mono-, oligo-, and polysaccharides), whereas under alkaline (i.e., aqueous NaOH) pretreatment conditions, the sulfur-free fractions of aliphatic carboxylic acids, lignin, and ex…
Activated carbon from hydrolysis lignin: Effect of activation method on carbon properties
2022
This study presents the effects of different activation methods to produce activated carbon from the hydrolysis lignin. Pretreatment of the feedstock with common mineral acids (HCL, HNO3, and H3PO4), different steam rates for physical activation, and different chemical activating agents (ZnCl2, Na2CO3, and KOH) for chemical activation were investigated. The pretreated biomass was carbonized and activated in one-stage process and the surface characteristics, such as total pore volume, pore size distribution and specific surface area, were investigated. The results showed that the activated carbon surface properties were not greatly affected by acid pretreatment. Brunauer-Emmett-Teller (BET) …
Un estudi exploratori sobre el procés de modelització amb dades reals en l'entorn informàtic dels iPads
2013
El treball d’investigació que presentem és un estudi exploratori sobre l’ensenyament i l’aprenentatge del procés de modelització d’una situació real en un grup d’alumnes de 1r de batxillerat. La peculiaritat d’aquest estudi és l’ús de dades reals obtingudes a partir de la gravació d’un vídeo del fenomen estudiat utilitzant iPads®. En particular, el model d’ensenyament que utilitzem permet treballar els conceptes de paràmetre i família de funcions i fa èmfasi en l’anàlisi qualitatiu del fenomen. The research work that we present is an exploratory study about teaching and learning the modelling process of a real situation in a grade 11 student group. The peculiarity of this study is the usage…
Atbilstības dzimumu normām, pārrunu stila un interešu fokusa saistība ar pretreakcijas efektu
2022
Pētījuma mērķis bija noskaidrot, kā pārrunu vadīšanas stils (asertīvs/ neasertīvs) un interešu fokuss (savas/citu intereses) ietekmē pretreakciju pret pārrunu dalībnieku atkarībā no viņa dzimuma, un kā atbilstība dzimuma lomas normām prognozē pretreakcijas efektu pārrunās. Izlasi veido n=372 (84%) sievietes un n=69 (16%) vīrieši, vecumā no 18 līdz 70 gadiem (M=40, SD=10,23), 85% respondentu ir augstākā izglītība. Pētījumam ir eksperimentāls starpgrupu dizains 2x2x2. Pētījumā tika adaptēta Sociālās pretreakcijas efekta skala (Amanatullah & Tinsley, 2013). Iegūtie rezultāti uzrāda interešu fokusa prognozējamo efektu uz pretreakciju pārrunās (pārstāvot cita intereses, tā samazinās). Pētījums a…
The transformation of the Horatian Sabine farm in Persius? Satire 6
2020
The purpose of this article is to focus on the motif of the countryside in Roman satire. In particular, it aspires to study the way the Sabine farm is delineated in Horace's Satire 2.6 and later in his Epistles, in order to elucidate the evolution of this motif in Persius? 6th Satire. In this poem, Persius addresses Caesius Bassus, who retreats to Sabine to seek poetic inspiration, but seems trapped in the paths of earlier poetry and cannot attain bliss, while the poet achieves it in the port of Luna.
Acid-catalyzed mechanocatalytic pretreatment to improve sugar release from birch sawdust : Structural and chemical aspects
2022
This study examined acid-catalyzed mechanocatalytic pretreatment of birch sawdust without a separate impregnation step. Catalyst amount and pretreatment time were the key variables. Pretreated material was mixed with water for hydrolysis (100 °C, 60 min). The efficient release of total reducing sugars from birch sawdust is significant to the path towards biofuels and biochemicals. Based on the results, the structure and surface of birch sawdust changed as a function of mechanocatalytic pretreatment. Milling time caused significant transformations in birch structure and also increased the yields of reducing sugars. The highest yield of total reducing sugar from pretreated sawdust was 23.0% a…
Satyrae del ilustrado portugués D. Francisco Botelho de Moraes e Vasconcelos (1670-1747): introducción, edición latina, traducción y comentario de fu…
2013
Nuestro trabajo consiste básicamente en: 1) Una introducción que aborda: a) la vida y obra del ilustrado portugués D. Francisco Botelho de Moraes e Vasconcelos (1670-1747), miembro honorario de la Real Academia Española y autor de la obra latina Satyrae; b) la vida y obra de D. Juan González de Dios (1684-1761), Catedrático de Prima de Humanidad de la Universidad de Salamanca, que escribió un comentario a dicha obra titulado: Notae ad Satyras. 2) Una edición crítica del texto latino de las Satyrae de Botelho y de las Notae ad Satyras de González de Dios. 3) Una traducción castellana completa. No existía anteriormente ninguna traducción a ninguna lengua moderna. 4) Numerosas notas que ayudan…
Effect of abrasive pretreatment on hot dried goji berry
2015
Goji (Lycium barbarum L.) is a Solanaceous deciduous shrub that grows in China, Tibet and other parts of Asia. Nowadays, goji berries are known as being very rich in nutrients with high antioxidant capacity, fact for which they were included in the novel category of “superfruits”. Goji berries contain high amounts of antioxidants, carotenoids, vitamin A and zeaxanthin. Most of goji berries produced are dried because they are very delicate fruits. Drying process improves fruit stability, since it decreases considerably the water activity of the food, reduces microbiological and enzymatic activity and minimizes physical and chemical reactions during storage. However, drying of goji berries ca…
MR3631681 Reviewed Nigsch, E. A.(A-WIENM) On a nonlinear Peetre's theorem in full Colombeau algebras. (English summary) Comment. Math. Univ. Carolin.…
2017
Colombeau algebras are defined as quotients of spaces containing the representatives of generalized functions given by smooth mappings: R:C∞(Ω,D(Ω))→C∞(Ω), where Ω is an open subset of Rn. In this paper the notion of locality defined by the author for a representative R of a nonlinear generalized function is characterized in such a way that the representative depends only on its ∞-jet. Finally, the author examines the possibility of defining a notion of order for the mapping R.
Biogas production from ensiled maize with and without hydrothermal pretreatment
2010
Energy crops are suitable substrates for anaerobic digestion. In the future their use will probably increase, and among other things optimum storage and pretreatment technologies should be developed. In this study eight maize silage varieties grown in Piikkiö, Southern Finland were used as substrates in anaerobic digestion. Also hydrothermal pretreatment was used to improve the biogas yield. Composition of the maize silage and the pretreated maize silage were analyzed and inhibitors were analyzed from the pretreated maize silage. The maize silages produce methane as much as fresh maizes in previous studies, when losses during the ensiling are taking into account and even 25-50 % more when l…