Production and Characterization of Energy Materials with Adsorbent Properties by Hydrothermal Processing of Corn Stover with Subcritical H2O

This work aims to investigate the effect of temperature on the process performance of hydrothermal processing (HTC) of corn Stover with subcritical H2O and on the morphology of solid products. The experiments were carried out at 200, 225 and 250 ºC, reaction time of 240 minutes, heating rate of 2.0 ºC/min, and biomass to water ratio of 1:10, using a pilot scale stirred tank reactor (STR) of 5 gallon, operating in batch mode. The process performance analyzed by computing the yields of solid and liquid reaction products (RLP). The aqueous phase (H2O + RLP) was physicochemical analyzed for pH and total carboxylic acids, expressed as total acetic acid content. The chemical compositions of carboxylic acids, furfural, and hydroxymethylfurfural (HMF) in the aqueous phase determined by GC-MS and HPLC. The results showed solid yields ranging from 57.39 to 35.82% (wt.), and liquid reaction products (RLP) yields ranging from 39.53 to 54.59% (wt.). The solid phase products were characterized by scanning electron microscopy (SEM), energy dispersive X-ray spectroscopy (EDX), and X-ray diffraction (XRD). The chemically activated (2.0 M NaOH) solid phase energy material obtained by HTC at 250 °C, applied as adsorbent to investigate the capacity and/or efficiency to adsorb acetic acid from 1.0 to 4.0 g/L model solutions at 25 °C. The solid phase yield decreases along with the temperature, showing an inflection region between 200 and 225 °C, whereas a drastic change takes place, while that of liquid phase increases, showing also a drastic change between 200 and 225 °C. The total acetic acid content of aqueous phase varied from 4064 to 5387 mg/L, while the pH from 3.77 to 3.91. The GC analysis identified the presence of volatile carboxylic acids, particularly acetic acid, in concentrations between 4020 and 5040 mg/L. HPLC identified the presence of furfural and hydroxymethylfurfural, whose concentrations decrease exponentially and linearly along with the temperature between 686.7 and 0.0, and 443.9 and 0.0 mg/L, respectively, being both compounds not detectable at 250 °C. The elemental/ultimate analysis of solid products shows that carbon content increases, while the oxygen and hydrogen contents decrease, along with the temperature. The H/C and O/C ratios decrease linearly as process temperature increases, and the high heating value (HHV) of solid reaction products, an energy densified material, changes sharply between 200 and 225 °C, showing an increase with temperature. The SEM, EDX, and XDR indicates a change on the morphology and mineralogical phases present in solid reaction products with temperature, particularly at 250 °C. The activated solid phase has proven to be very selective to adsorb acetic acid, showing that recovery of acetic acid from hydrothermal carbonization/liquefaction aqueous solutions is feasible by using a multistage-stage adsorption process in series

Initial Growth Of Costus Longebracteolatus And Costus Spiralis 'french Kiss' Under Different Light Conditions

The Brazilian native Costus longebracteolatus and Costus spiralis 'French Kiss', in the family Costaceae, have been used as both cut flowers and cut foliage. It is known that Costus species grow better under partial shade, but studies on the influence of shading or light on plant growth, development, and flower production are still incipient. As this kind of information is essential on planning of planting, production, and agribusiness activities, the objective of this research was to evaluate the influence of different colored shade nets and light conditions on the initial growth of both C. longebracteolatus and C. spiralis 'French Kiss'. Plants, obtained from cuttings of pseudostems, were cultivated under six light conditions, which comprised six treatments, along 270 days: red net with 50% shading, blue net with 50% shading, black net with 70% shading, black net with 50% shading, black net with 30% shading, and full sun. The initial growth of C. longebracteolatus (up to 270 days) is more successful under the blue net with 50% shading, which promoted highest values of pseudostem length and dry matter of aerial part. For C. spiralis 'French Kiss' plants, both the red and blue nets with 50% shading implied best results and differed for the other treatments with greater pseudostem length. Plant exposure to full sun inhibited growth and development, and favored early leaf necrosis.22332633

Keeping Quality And Prolonging The Postharvest Longevity Of Spray Chrysanthemum Cv. White Polaris [manutenção Da Qualidade E Aumento Da Longevidade Floral De Crisântemo Cv. White Polaris]

Cut flowers of spray chrysanthemum (Dendranthema grandiflorum (Ramat.) S. Kitamura) cv. White Polaris were harvested and treated in pulsing solutions. The flowers were harvested in commercial greenhouses and transported to the laboratory where the whole stem and inflorescence were immersed in tap water at darkness, during 3 hours. The flowers were selected for uniformity in terms of development; the stems were trimmed to equal length (50 to 60 cm) and tagged to allow recording morphological changes associated with individual flowers. The flowers were held during 24 hours (pulsing treatment period) at 25 ±2°C and 60 to 90% of air relative humidity under continuous cool white fluorescent light at 1.5 KLx. At the end of the treatment, the flowers were transferred to distilled water, under daily 10 hours of continuous fluorescent light and at the same laboratory conditions already described. At the first experiment, it was tested the efficiency of 8-hydroxyquinoline (8-HQ) and thiabendazole (TBZ), as germicides, in three concentrations each one. Furthermore, two growth regulators were applied in order to keep the green color and the turgidity of leaves: gibberellic acid (GA3), 6-benzylaminopurine (6-BA) and a mix of them. At the second experiment, in order to extend the vase-life by inhibition of ethylene production, it was tested the effect of silver nitrate (AgNO3), anionic silver thiosulphate complex (STS) and cobalt chloride (CoCl2) into pulsing solutions in three concentrations each one. The results of experiments showed that pulsing treatment with distilled water + 0.52 mol/m3 citric acid + 58.43 mol/m3 sucrose + 0.69 mol/m3 8-HQ + 2.9 or 4.4 mol/m3 AgNO3, combined with foliar treatment of 0.058 mol/m3 GA3, improved the foliar quality and extended the flower vase life.552299307Baker, J.E., Preservation of cut flowers (1983) Plant Growth Regulating Chemicals, 2, pp. 177-191. , NICKELL, L. G., ed. Boca Raton, CRC PressBeyer Jr., E.M.A., Potent inhibitor of ethylene action in plants (1976) Plant Physiology, 58, pp. 268-271. , LancasterCoorts, G.D., Internal metabolic changes in cut flowers (1973) HortScience, 8 (3), pp. 195-198. , St. JosephVan Doorn, W.G., Perik, R.R.J., Hydroxyquinoline citrate and low pH prevent vascular blockage in stems of cut rose flowers by reducing the number of bacteria (1990) Journal of American Society for Horticultural Science, 115 (6), pp. 979-981. , AlexandriaFlórez-Roncancio, V.J., De Castro, C.E.F., Demattê, M.E.S.P., Determinação do ponto de coIheita e indução àa bertura floral do crisântemo cultivar White Polaris em diferentes concentrações de sacarose (1995) Bragantia, 54 (1), pp. 113-119. , CampinasFord, H.E., Clark, D.T., Stinson, R.F., Bacteria J associated with cut flowers containers (1961) Proceedings of the American Society for Horticultural Science, 77, pp. 635-636. , St. J JosephGindin, E., Tirosh, T., Mayak, S., Effects of flooding on ultrastructure and ethylene production in chrysanthemums (1989) Acta Horticulturae, 262, pp. 171-183Halevy, A.H., Treatments to improve water balance of cut flowers (1976) Acta Horticulturae, 64, pp. 223-230. , AasHalevy, A.H., Mayak, S., Improvement of cut flower quality opening and longevity by pre-shipment treatments (1974) Acta Horticulturae, 43, pp. 335-347. , The HagueHalevy, A.H., Mayak, S., Transport and conditioning of cut flowers (1974) Acta Horticulturae, 43, pp. 291-306. , The HagueHalevy, A.H., Mayak, S., Senescence and postharvest physiology of cut flowers. Part 2 (1981) Horticultural Rewiews, 3, pp. 59-143. , JANICK, J., ed.. WestportHeide, O.M., Oydvin, J., Effects of 6-Benzylamino-purine on the keeping quality and respiration of glasshouse carnation (1969) Horticultural Research, 9, pp. 26-36. , EdinburghKofranek, A.M., Opening flowers buds after storage (1976) Acta Horticulture, 64, pp. 231-237. , AasKofranek, A.M., Cut chrysanthemums (1980) Introduction to Floriculture, pp. 3-45. , LARSON, R. A., ed.. New York, Academic PressKofranek, A.M., Paul, J.L., The value of impregnating cut stems with high concentrations of silver nitrate (1974) Acta Horticulturae, 41, pp. 199-206. , The HagueLarsen, F.E., Cromarty, R.S., Micro-organism inhibition by 8-hydroxyquinoline citrate as related to cut flower senescence (1967) Proceedings of the American Society for Horticultural Science, 90, pp. 546-549. , St. JosephLarsen, F.E., Scholes, J.F., Effects of 8-hydroxyquinoline citrate, N-dimethylamino succinamic acid, and sucrose on vase life and spike characteristics of cut snapdragons (1966) Proceedings of the American Society for Horticultural Science, 89, pp. 694-701. , St. JosephLau, O.L., Yang, S.F., Inhibition of ethylene production by cobaltous ion (1976) Plant Physiology, 58, pp. 114-117. , LancasterLaurie, A., Studies on the keeping qualities of cut flowers (1936) Proceedings of the American Society for Horticultural Science, 34, pp. 595-597. , St. JosephMaclean, D.C., Dedolph, R.R., Effects of N6benzylaminopurine on post-harvest respiration of Chrysanthemum morifolium and Dianthus caryophyllus (1962) Botanical Gazette, 124 (1), pp. 20-21. , ChicagoMarousky, F.J., Water relations, effects of floral preservatives on bud opening and keeping quality of cut flowers (1972) HortScience, 7 (2), pp. 114-116. , St. JosephMetivier, J.R., Citocininas (1985) Fisiologia Vegetal, 2, pp. 93-127. , FERRI, M. G., ed. São Paulo, EPU, 2vPaulin, A., Muloway, K., Perspective in the use of growth regulators to increase the cut flowers vase life (1979) Acta Horticulturae, 91, pp. 135-141. , SkierniewiceReid, M.S., Postharvest handling of cut flowers (1980) Horticultural Crops - Perishables Handling, 45, pp. 1-6. , DavisRogers, M.N., An historical and critical review of postharvest physiology research on cut flowers (1973) HortScience, 8 (3), pp. 189-194. , St. JosephSaradhi, P.P., Ram, H.Y.M., Prolongation of vase-life of chrysanthemum blooms by cobalt chloride and its reversal by IAA (1989) Acta Horticultural, 261, pp. 309-312Stoddard, E.M., Miller, P.M., Chemical control of water loss in growing plants (1962) Science, 137, pp. 224-225. , WashingtonVeen, H., Van Geijn, S.C., Mobility and ionic form of silver as related to longevity of cut carnations (1978) Planta, 140, pp. 93-96. , BerlinWoltering, E.J., Van Doorn, W.G., Role of ethylene in senescence of petals - Morphological and taxonomical relationships (1988) Journal of Experimental Botany, 39 (208), pp. 1605-1616. , OxfordYang, S.F., Regulation of ethylene biosynthesis (1980) HortScience, 15 (3), pp. 238-243. , St. Josep

Hastes florais de helicônia sob deficiência de macronutrientes Flower stems postharvest characteristics of heliconia under macronutrients deficiency

O objetivo deste trabalho foi avaliar características pós-colheita da primeira haste floral de plantas de Heliconia psittacorum x H. spathocircinata Aristeguieta, cultivar Golden Torch, sob deficiência de macronutrientes. O experimento foi conduzido em casa de vegetação, mediante técnica do elemento faltante. As inflorescências produzidas do tratamento sob omissão de N apresentaram coloração laranja-pálido e deformação nas hastes florais. O comprimento e o diâmetro da haste floral e o comprimento da inflorescência foram reduzidos nos tratamentos com omissão de N, P ou K em até 31,23%, em relação ao tratamento completo. A massa de matéria seca e a durabilidade pós-colheita das hastes florais foram reduzidas em 67 e 38,46%, respectivamente, em ambos os tratamentos com omissão de N ou K. As deficiências desses macronutrientes reduziram, ainda, a produção de hastes florais, a partir do segundo perfilho emitido. Hastes florais com maior massa de matéria seca e diâmetro apresentaram maior durabilidade pós-colheita. O teor de carboidrato na parte subterrânea mostrou correlação positiva (0,90) com a massa de matéria seca das hastes florais. Hastes florais com maior teor de carboidratos solúveis nas folhas retardaram a emissão da inflorescência.<br>The objective of this work was to evaluate Heliconia psittacorum x H. spathocircinata Aristeguieta 'Golden Torch' first flower stem morphological and physiological characteristics as well as postharvest longevity, under macronutrients omissions. A greenhouse experiment was conducted under the technique of the lacking element. Inflorescences produced under N omission treatment showed a pale orange color and floral stem deformation. Stem length and diameter as well as inflorescence length were reduced under omission of N, P or K, down to 31.23% when compared to the complete solution treatment. Floral stem dry matter and postharvest longevity were reduced on 67% and 38.46%, respectively, on either N or K omission treatments. These nutrients omission treatments reduced floral stem production from the second shoot emitted. Greater postharvest longevity is to be found at higher floral stem diameter and dry matter. Carbohydrate ratio in underground parts presents positive correlation (0.90) with floral stem dry matter. Floral stems showing greater carbohydrate ratio on the leaves withdraw inflorescence appearance