Cultivo de colza para produção de biodiesel

Cultivo de colza para produção de biodieselO presente trabalho teve como objetivo principal estudar a adaptação da colza às condições de cultivo do Nordeste de Portugal. Procedeu-se ainda à determinação laboratorial do teor de óleo em sementes de colza. A partir de óleos alimentares usados foi produzido biodiesel e determinados os índices de iodo e de acidez, de acordo com as normas EN14111 e EN14104, respetivamente. Aspetos pouco conhecidos sobre a mecanização de operações culturais como a sementeira e colheita foram estudados, tendo-se encontrado algumas respostas para as características que o semeador a eleger deve conter e regulações a efetuar na ceifeira- -debulhadora a usar na colheita. A produção de colza em campo foi bastante penalizada pelas condições de seca severa que se registaram no Inverno e início da Primavera desse mesmo ano, não tendo sido possível observar efeitos significativos entre as diferentes modalidades experimentais. A produção média de colza em cada um dos talhões foi da ordem de 1000 kg semente ha-1. O teor em óleo das sementes de colza variou entre 41.7 e 42.0%. Relativamente ao índice de acidez do biocombustível obteve-se 0.16 g KOH/g amostra e quanto ao índice de iodo registou-se o valor de 130.32 g iodo/100 g de biocombustível

Into the depths of deep eutectic solvents

Ionic liquids (ILs) have been successfully tested in a wide range of applications; however, their high price and complicated synthesis make them infeasible for large scale implementation. A decade ago, a new generation of solvents so called deep eutectic solvents (DESs) was reported for the first time. DESs show similar properties to ILs and they have proven to be an excellent alternative to ILs in many applications where ILs succeeded first. Besides, DESs can be prepared easily and cheaply, with low-cost starting materials, no need of solvents, no atom loss during the formation and no additional purification requirements. The main problem that scientist are facing when they want to use DESs in different applications is the lack of information on the fundamentals of these solvents. Why do they form? How do they form? How do the hydrogen bond donor (HBD) and the hydrogen bond acceptor (HBA) interact? How do DESs interact with other compounds? Can we predict their thermophysical properties? The answer to these questions will provide to researches new insights on the application of these solvents, solving the problem of trial-and-error experimentation. In this work, we present a detailed analysis of molecular interactions and conformational states of two selected DESs: lactic acid – choline chloride (2:1) and glycolic acid – choline chloride (1:1), using density functional theory (DFT) and second-order Møller¿Plesset perturbation theory (MP2) with various basis sets. Theoretical calculations were performed using the GAUSSIAN 03 software package. The obtained results are used to evaluate the nature of interactions between the HBD and HBA and their structural features. Additionally, it will contribute to the better understanding of how DESs are formed

Utilization of Pachysolen tannophilus and Pichia kudriavzevii for the production of xylitol on undetoxified corn cob hydrolysates

Received: February 19th, 2022 ; Accepted: April 24th, 2022 ; Published: April 29th, 2022 ; Correspondence: [email protected] is a natural polyol with broad applications in the food and pharmaceutical industries. However, its large-scale production through chemical means is still an expensive and not environmentally friendly process. Therefore, great attention has been paid to low-cost and renewable substrates like corn cobs (CC), which can be utilized to improve the economic outlook of xylitol production. In this study, CC were used as a feedstock for xylitol production, with the help of yeasts and filamentous fungi. The results obtained in this study showed that the amount of xylitol produced from CC hydrolysate was similar to the amount of xylitol obtained on xylose substrate. Overall, yeast produced higher amounts of xylitol than filamentous fungi. Pachysolen tannophilus had the highest xylitol production at pH 5.0, 72 h fermentation time, substrate concentration 15%, and inoculum size 1.5×108 cfu mL-1 , while Pichia kudriavzevii performed better at pH 5.0, with a 72 h fermentation time, substrate concentration of 20%, and inoculum size of 2.5×108 cfu mL-1 . When comparing the combined optimal parameters with and without supplementation, supplementation with 1.5% methanol, has increased the xylitol production of P. tannophilus and P. kudriavzevii by 31% and 18.6%, respectively. These findings demonstrate the robustness of these yeast strains for sustainable and cost-effective xylitol production from CC waste

Phosphate solubilization potential of indigenous rhizosphere fungi and their biofertilizer formulations

Received: September 28th, 2021 ; Accepted: December 13th, 2021 ; Published: December 16th, 2021 ; Correspondence: [email protected] harmful effects of chemical fertilizers on soil, plants, and eco-systems have stimulated the growth of the global biofertilizer market. However, biofertilizer use remains limited in developing countries due to inadequate research and poor technology. The use of readily available materials for biofertilizer production can be a good starting point. This study aimed to investigate phosphate-solubilizing potentials of soil fungi and the shelf-life of their biofertilizer formulations using sawdust and charcoal as carriers. Soil samples from the rhizosphere were cultured on Pikovskaya (PVK) agar, and the best phosphate solubilizers (Aspergillus niger, Aspergillus fumigatus and A. flavus) were screened for their phosphatesolubilization potentials on solid medium. Results obtained showed that A. niger had the highest solubilization index of 1.72, followed by A. fumigatus, and A. flavus with a solubilization index of 1.01 and 0.95, respectively. Optimization studies showed that after 5 days of incubation, A. niger, A. flavus and A. fumigatus solubilized 149, 112 and 126 mg L-1 of phosphate, respectively. These values increased to 549 mg L-1 on day 11 for A. niger, 379 mg L-1 on day 9 for A. flavus and 430 mg L-1 on day 9 for A. fumigatus. Furthermore, A. fumigatus and A. flavus proved to be better inoculants than A. niger as they maintained higher CFU g-1 counts throughout the experiment. Also, sawdust supported higher counts of the three inoculants than charcoal and was thus the best carrier. The findings demonstrated that these aspergilli can be harnessed for improving soil fertility and plant development

2,6-Diphenylpyridine

In the title compound, C17H13N, the dihedral angles between the pyridine ring and the phenyl rings are 29.68 (18) and 26.58 (17)°. In the crystal structure, the mol­ecules are linked by a weak C-H inter­action, leading to [01] chains. There are no further significant inter­molecular inter­actions

Do the low molecular weight heparins improve efficacy and safety of the treatment of deep venous thrombosis? A meta-analysis

We compared the efficacy and safety of low molecular weight heparins (LMWH) and unfractionated heparin (UFH) in the treatement of deep venous thrombosis (DVT). A comparison between two daily subcutaneous injections of LMWH against a single injection was also performed. DESIGN AND METHODS: The study was performed by a meta-analysis. Clot improvement in venography, recurrency, total mortality and major hemorrhages were assessed in 4,472 patients with DVT from 21 studies treated with subcutaneous LMWH or UFH. RESULTS: An improvement in clot reduction (odds ratio 0.73, 95% confidence interval 0.59 to 0.90, p = 0.004), a decrease in total mortality (0. 68, 0.50 to 0.91, p = 0.012) and a lower incidence of hemorrhage (0. 65, 0.43 to 0.98, p = 0.047) were observed in LMWH treated patients. There were no differences in recurrences (0.78, 0.59 to 1.04, p = 0. 10). A single dose of LMWH was better than two in reducing major bleeding (c2 = 4.99, p = 0.025); however, the two dose regimen was more effective in clot reduction (c2 = 8.56, p = 0.004). INTERPRETATION AND CONCLUSIONS: LMWH is superior to UFH in terms of safety and efficacy. A single daily dose of LMWH dose is a suitable therapeutic regimen and could facilitate the outpatient treatment of venous thromboembolism

Desempenho de um semeador adaptado para sementes pequenas

A sementeira mecânica de sementes pequenas (2.5 g – 7.6 g / 1000 grãos) nem sempre é executada com eficiência, quer pela reduzida quantidade de semente a aplicar por unidade de área (100 a 200 grãos por m2), quer pela reduzida profundidade de sementeira, até 1 a 2 cm. Com o objetivo de avaliar o desempenho do semeador Sola Trisem 194 neste tipo de sementeira foram realizados ensaios de campo com Brassica Napus L., sendo medidos por cronometragem os tempos elementares de trabalho e calculadas a capacidade de trabalho e eficiência de campo.info:eu-repo/semantics/publishedVersio

El gusano tornillo: una amenaza para las plataneras.

El gusano tornillo (Castniomera humbolti) constituye una plaga de importancia económica en zonas plataneras de varios departamentos del país. Se describen las características morfológicas y duración de los distintos estados de este Lepidoptero, el tipo de daño que ocasiona, las plantas hospederas y las prácticas recomendadas para su contro