Application of electro-technologies in the processing of flax and hemp stems
Notice bibliographique
Résumé
Plant based natural fibers are extracted from various parts of the plants such as leaf, inner bark and fruit/seed. Flax (Linum usitatissimum) and hemp (Cannabis sativa) stems were selected for the research because both flax and hemp are important crops in Canada.The main objectives of this study were: 1) To develop a novel retting method for the processing of pre- soaked flax and hemp stems by the application of microwave energy to the flax water mixture; 2) To evaluate the efficiency of retting in relation to the changes in compounds present in the fibers such as cellulose, hemicellulose, lignin and pectin through chemical analysis and 3) To develop an effective electro- osmotic dewatering system for the high moisture retted flax and hemp stems using a bench type roller press at various applied voltages.After the initial analysis of water retted flax stems, a novel retting method was introduced by applying microwave energy and studies were conducted to establish the effect on pre- soaked flax stems. The combined effect of pre- soaking, microwave volumetric heating and the non- thermal effect of microwave energy resulted in retted flax stem. Retting efficiency was observed at various combinations of pre-soaking, microwave treatment times and microwave energy levels. The microwave- assisted retting was repeated on the hemp stems to investigate the acceptability of this method in hemp varieties. NIR analysis and diameter distribution analysis were performed to study the efficiency of retting. Microwave- assisted retting on flax and hemp was proved to be efficient from the analysis of the compounds (lignin, hemicellulose and cellulose) presented in the fibers and its diameter distribution. After establishing the microwave- assisted retting of flax and hemp stems, the next step was to study the chemical changes occurring in the fibers during microwave assisted retting, and flax stem was selected for the analysis and studies were performed by gravimetric methods. Cellulose, hemicellulose, lignin and pectin concentrations and the sugar content in the solution obtained after the treatment were investigated. Cellulose percentage in the fiber was increased significantly with the increase of microwave power, which proved the release of cellulosic fiber with the application of microwave energy during retting. Hemicellulose, lignin and pectin concentrations decreased significantly after microwave-assisted retting which explained the degree of retting with the help of microwave energy. Fully soaked flax and hemp stems after microwave- assisted retting was collected at very high moisture level and those stems have to be dried to a lower moisture level of around 10% for further decortication to separate the fibers or to 4% for storage. To ease the drying process, an electro- osmotic bench type roller press system was introduced for the dewatering of retted flax and hemp stems. Since the pre- soaked stems are slightly charged, water molecules moved towards the anode when the stems were subjected to electro- osmosis between two electrodes. The applied pressure between two electrodes, the applied voltage and the pre- soaking time of the stems were the factors affecting the electro-osmotic dewatering. The stems after dewatering were subjected to short term microwave- assisted drying at controlled temperature and then moved to a fiber processing facility where the retted stems were decorticated to biofibers. Effectively retted stems with appropriate electro- technology produces high quality fibers whereas non- retted, under retted and overly retted stems lead to the production of low quality fibers.
Récupéré en direct depuis OpenAlex et désinversé. Les résumés ne sont pas conservés dans cette base de données : les index inversés représentent 8,6 Go des 9,3 Go de texte de la base, et le serveur dispose de 13 Go libres.
Comment cette classification a été obtenuedéplier
Prédiction distillée sur la base complète
Imitation des enseignantsNi prévalence calibrée, ni vérité terrain. Validation humaine à venir. Apprise à partir de 10 348 étiquettes directes de Codex et de 10 348 étiquettes directes de Gemma. Le mode candidate est l'union des têtes enseignantes seuillées; le consensus est leur intersection. Ces sorties portent le statut machine_predicted_unvalidated et ne sont ni des étiquettes humaines ni des étiquettes directes de modèles de pointe.
Scores Codex et Gemma par catégorie
| Catégorie | Codex | Gemma |
|---|---|---|
| Métarecherche | 0,001 | 0,000 |
| Méta-épidémiologie (sens strict) | 0,000 | 0,000 |
| Méta-épidémiologie (sens large) | 0,000 | 0,000 |
| Bibliométrie | 0,000 | 0,000 |
| Études des sciences et des technologies | 0,000 | 0,000 |
| Communication savante | 0,000 | 0,000 |
| Science ouverte | 0,000 | 0,000 |
| Intégrité de la recherche | 0,000 | 0,001 |
| Charge utile insuffisante (le modèle a refusé de juger) | 0,000 | 0,000 |
Scores machine (provisoires)
Les deux têtes enseignantes du modèle étudiant, lues sur ce travail. Un score ordonne la base pour la relecture; il n'affirme jamais une catégorie, et le statut de validation accompagne chaque rangée tel quel.
Scores de référence d'un modèle non mature (critères de maturité non atteints, 7 itérations). Un score ordonne; il n'affirme jamais une catégorie.
score_only:v0-immature-baseline · tel quel depuis la passe de notation : score_only signifie que le nombre peut ordonner les travaux, et qu'aucune étiquette de catégorie n'en découleClassification
machine, non validéePrédiction automatique; un appel candidat d’une seule tête enseignante, pas un consensus.
Le détail, modèle par modèle et score par score, se trouve en fin de page sous « Comment cette classification a été obtenue ».