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991.
Carolina Fonseca Couto Wagner Guadagnin Moravia Miriam Cristina Santos Amaral 《Clean Technologies and Environmental Policy》2017,19(8):2057-2073
This study investigates the application of a hybrid microfiltration–nanofiltration (MF–NF) process for textile wastewater reclamation. Indigo blue dye was efficiently retained by an MF membrane, allowing its recovery from the concentrated stream. NF technology was successfully applied to polish textile effluent. The NF membrane was evaluated under different transmembrane pressure (8–15 bars), crossflow velocities (0.21–0.84 cm s?1), pH (7–11), and feed temperature (20–40 °C). The best NF performance was provided at a pressure of 12 bar and a crossflow rate of 0.63 cm s?1. The NF performance (in terms of COD, conductivity, colour, and nitrogen removal) was not influenced by pH; however, higher feed pH values resulted in increased membrane fouling. The principal cause of flux decline was due to concentration polarization. Membrane chemical cleaning was sufficient to regain the initial permeability. The NF permeate met the quality requirements for all water demands within the textile industry, while the NF concentrate could be used to wash equipment, print work screens, print paste containers, and floors. The total capital cost (CapEx) of the MF–NF system was estimated at 58,362.50 US dollars and the total operational cost (OpEx) at 0.31 US dollars per cubic metre of effluent. 相似文献
992.
Oran Ana Carolina Santos Gleison Gadelha Bruno Conte Tayana 《Requirements Engineering》2021,26(4):481-508
Requirements Engineering - Requirements specifications are essential to properly communicate requirements among the software development team members. However, each role in the team has different... 相似文献
993.
994.
Carolina Valenzuela Lilian Abugoch Cristian Tapia Alexander Gamboa 《International Journal of Food Science & Technology》2013,48(4):843-849
It is important to produce hydrophobic edible protein films for use in foods. The aim of this study was to evaluate the effect of alkaline extraction of quinoa proteins (QP) on the structure and their film‐forming ability without plasticiser. QP were extracted between pH 8 to 12, and their structure was evaluated by PAGE‐SDS, size‐exclusion HPLC light scattering, fluorescence spectroscopy and SH and SS. Film was characterised by FTIR, SEM, tensile strength, barrier and colour. Structural changes of QP showing that alkalinisation over pH 10 produce significant denaturation/aggregation/dissociation structural changes in QP. pH 12 was the condition to form a film (film12). FTIR showed hydrogen bonds and hydrophobic film interactions. Film12 had 16.6 ± 3.8% elongation and 15.7 ± 1.1 MPa tensile strength, and water vapour permeability was 5.18 ± 0.38 g mm m?2 day?1 kPa?1. Film12 had a brownish colour. A high degree of denaturation/aggregation/dissociation of QP structure is required to form a film without plasticiser. 相似文献
995.
The levels of free and total tryptophan and of 5-hydroxytryptophan (5-HTP) were investigated in green and roasted grains and beverages of Coffea arabica L. (Arabica) and Coffea canephora Pierre var. robusta (Robusta). Grains were light, medium and dark roasted. Free and protein tryptophan were extracted before and after hydrolysis. The levels of tryptophan and 5-HTP were quantified simultaneously by ion-pair HPLC and fluorimetric detection after derivatisation with o-phthalaldehyde. Robusta green coffee had higher total and protein tryptophan, whereas Arabica had higher free tryptophan levels. 5-HTP was not detected in the samples before and after roasting. Free tryptophan was completely degraded during roasting. Roasting significantly affected protein tryptophan. The rate of loss was smaller in Arabica compared to Robusta at every roasting degree. A beverage prepared the Brazilian way with a medium-roasted coffee provided 1.4–2.5 mg tryptophan/50 ml cup. 相似文献
996.
997.
Proteases are one of the most important groups of industrial enzymes, with considerable application in the food industry. The aim of this work was to study a novel protease produced by the thermophilic fungus, Thermoascus aurantiacus, through solid-state fermentation (SSF). The enzyme acted optimally at pH 5.5 and 60 °C; it was stable up to 60 °C for 1 h and in the pH range 3.0–9.5. To elucidate the enzyme’s proteolytic activity, its hydrolytic profile on bovine casein, an important protein in the food industry, was studied by enzymatic hydrolysis on skim milk, analyzed by gel electrophoresis (UREA-PAGE), which clearly showed that the protease does not have the same specificity as bovine chymosin. 相似文献
998.
Sonja Ellen Lobo Francisco Henrique Lanna Wykrota Ana Carolina Marques Barbosa Oliveira Irina Kerkis Germán Bohorquez Mahecha Humberto José Alves 《Journal of materials science. Materials in medicine》2009,20(5):1137-1147
Biphasic bioceramics have been widely indicated for bone reconstruction; however, the real gain in bone mass due to the presence
of such biomaterials has not been established yet nor the advantages of its association with platelet concentrate. This study
aims at quantifying the volume of bone matrix, osteoblasts, osteocytes, blood vessels and adipose tissue after the application
of a biphasic bioceramics composed of 65% hydroxyapatite and 35% β-tricalcium phosphate. Critical-size bone defects were produced
in rabbit femora and reconstructed with bioceramics only, with bioceramics combined with platelet concentrate, with platelet
concentrate alone, and with no treatment (blood clot). The quantitative evaluation was performed on histological sections
using histomorphometry. Our data provide original evidence that consolidates the indication of bioceramics for clinical bone
loss reconstruction. The application of biphasic bioceramics alone led to major bone mass gain and was followed by its association
with platelet concentrate. On the other hand, platelet concentrate can contribute to the augmentation and maintenance of the
adipose tissue, representing a new field for future applications in plastic surgery. 相似文献
999.
Albert Westergren Christine Wann-Hansson Elisabet Bergh Börgdal Jeanette Sjölander Rosmarie Strömblad Rosemarie Klevsgård Carolina Axelsson Christina Lindholm Kerstin Ulander 《Nutrition journal》2009,8(1):20-8
Background
To explore the point prevalence of the risk of malnutrition and the targeting of nutritional interventions in relation to undernutrition risk and hospital volume. 相似文献1000.
Hydrodesulfurization (HDS) of dibenzothiophene (DBT) was carried out in a batch reactor at 3.3 MPa and 340 °C. Sulfided catalysts showed a wide range of activity variation as a function of support composition, which established that sulfided active phases strongly depend on the nature and composition of support. The incorporation of MgO, SiO2, TiO2 and ZrO2 with γ-Al2O3 alters the nature of active phase interactions on the support surface. Therefore, these oxides play a structural promoting role to the support contribution and its interaction towards the active metal geometry. Different preparation methods of catalysts were carried out by using different additives during the impregnation. It is demonstrated that co-impregnation method found better activity than sequential impregnation. The urea additive prepared catalyst provides promising activity compared with other chelating agents. An Al2O3-B2O3 mixed oxide supported catalyst was tested at high pressure with real feed (Maya heavy oil diluted with hydrodesulfurized diesel). The mixed oxide supported catalyst showed rapid deactivation with time-on-stream than the alumina supported catalyst that may be due to an enhancement in acidic sites. The activity results demonstrated that the number of catalytic sites is a combination of support composition, additive, impregnation pH, drying and calcinations of catalysts. 相似文献