Search results for " pre-treatment"

Chemometric Study on Alkaline Pre-treatments of Wood Chips Prior to Pulping

2016

Alkaline pre-treatments were performed for the production of organics-containing effluents from silver/white birch (Betula pendula/pubescens) and Scots pine (Pinus sylvestris) chips prior to chemical pulping. Pre-treatment conditions were varied with respect to time (from 30 min to 120 min), temperature (130 °C and 150 °C), and alkali charge (1, 2, 3, 4, 6, and 8% of NaOH on oven-dried wood). The analytical data (total content, weight average molar mass, and molar mass distribution) on dissolved lignin were subjected to principal component analysis to examine the relationship between molar mass and molar mass distributions in lignin removed from different wood species under varying alkaline…

BIOGLASS® integration in Poly-L-Lactic-Acid scaffolds produced via Thermally Induced Phase Separation (TIPS).

In this work, a method of integration of BG particles in polymeric scaffold was developed with a trial and error procedure. The main purpose was to obtain highly porous and mechanically stable bioactive devices.

Sulfur-free pulping of hot-water-extracted spruce sawdust

2016

Softwood (Picea abies) sawdust was hot-water-extracted with two multi-phase processes (160-180°C, 100-280 min, and liquor-to-wood ratio 5 l/kg) corresponding to P-factors of ~780 (yield 80.0%) and ~4580 (yield 72.4%). The pre-treated materials were then pulped with the soda-AQ cooking (170°C, NaOH charge 20%, AQ charge 0.1%, 30-150 min, and liquor-to-wood ratio 5 l/kg), resulting in a yield range of 36.1-61.4% (for reference cooks without pre-extraction 47.9-60.0%). It was observed that the pre-extraction under moderate conditions enhanced the dissolution especially of large-molar-mass lignin during cooking, and the total amount of the dissolved lignin was also higher than that removed from…

Effects of clinical and laboratory variables and of pretreatment with cardiovascular drugs in acute ischaemic stroke: A retrospective chart review fr…

2009

Background: Few studies have examined the role of cardiovascular drugs on acute ischaemic stroke prognosis. Aims: To evaluate the relationship between a favourable outcome in patients with acute ischaemic stroke and specific demographic, clinical and laboratory variables and cardiovascular drug pretreatment. Methods: The 1096 patients enrolled in the GIFA study (who had a main discharge diagnosis of ischaemic stroke) represent the final patient sample used in this analysis. Drugs considered in the analysis included angiotensin converting enzyme (ACE)-inhibitors, angiotensin II receptor blockers, statins, calcium channel blockers, anti-platelet drugs, vitamin K antagonists and heparins. The …

Evaluation of carotenoids and furosine content in air dried carrots and parsnips pre-treated with pulsed electric field (PEF)

2019

Carrot and parsnip slices were subjected to hot drying at 50, 60 and 70 °C with or without pulsed electric field (PEF) pre-treatment at 0.9 kV/cm and 1000 and 10,000 pulses. The effect of drying on processed samples was assessed by analysis of carotenoids, the furosine value, total phenols and the Whiteness Index (WI). PEF pre-treatment is effective in reducing drying times, but the degree of cellular breakdown makes the compounds more susceptible to chemical and enzymatic reactions. In our condition PEF pre-treatment increased the carotenoid degradation and promoted the Maillard reaction above all at the highest temperature of 70 °C. The assessment of carotenoid stability, together with th…

Effect of a physical pre-treatment and drying on carotenoids of goji berries ( Lycium barbarum L.)

2018

In order to evaluate the influence of an abrasive pre-treatment and drying at 50 °C, 60 °C, 70 °C of goji fruits (Lycium barbarum L.), changes in colour and carotenoids were studied. An extraction method was modified and adapted to assay the main carotenoid esters and saponified carotenoids of goji berries, before and after treatments. Goji berries were confirmed as a high source of zeaxanthin, with zeaxanthin-dipalmitate at about 2 g/kg dry weight. The reliability of the analytical method was confirmed by the high quantitative recoveries, about 100%, a higher repeatability than reference methods and a good reproducibility (lower than 5%). After drying, significant but small carotenoid loss…

Influence of different dehydration levels on volatile profiles, phenolic contents and skin hardness of alkaline pre-treated grapes cv Muscat of Alexa…

2020

A dehydration experiment was carried out on Vitis vinifera L. cv Muscat of Alexandria (synonym Zibibbo) following the process for the production of renowned special dessert wines produced on Pantelleria island (Sicily, Italy). Harvested berries were pre-treated in a sodium hydroxide dipping solution (45 g/L, dipped for 185 s, 25 &deg