Search results for "Satu"
showing 10 items of 1367 documents
Separation of monoacylglycerols by reversed-phase high-performance liquid chromatography
1992
Abstract Reversed-phase high-performance liquid chromatography on a thermostated octadecylsilyl column was used to separate complex mixtures of monoacyglycerols formed by chemical deacylation of natural triacyclycerols. Acetonitrile-water mixtures were used for elution of the underivatized monoacylglycerols and a different refractometer was used for their detection. The order of elution of monoacylglycerols in complex mixtures varies as a function of the chain length, unsaturation, positional isomerism, analysis temperature and eluent water concentration. The peak areas were representative of the amounts of monoacylglycerols detected. The method can be applied to compositional analysis and …
Soil microbial biomass carbon and fatty acid composition of earthworm Lumbricus rubellus after exposure to engineered nanoparticles
2014
none 6 no First Online: 14 October 2014 The aim of this work was to investigate the effect of engineered nanoparticles (NPs) on soil microbial biomass C (MBC) and on earthworm Lumbricus rubellus. An artificial soil was incubated for 4 weeks with earthworms fed with vegetable residues contaminated by NPs, consisting of Ag, Co, Ni and TiO2. After the treatments, soils were analysed for MBC and total and water soluble metal-NPs, whereas earthworms were purged for 28 days and then analysed for fatty acids (FAs) and total metal-NPs. Longitudinal sections of earthworms were investigated by environmental scanning electron microscopy (ESEM), equipped with energy-dispersive X-ray spectroscopy (EDS),…
Biobased Epoxy Resin by Electrochemical Modification of Tall Oil Fatty Acids
2019
A biobased epoxy resin was prepared from tall oil fatty acids (TOFAs), a byproduct of the pulping industry. As free carboxylic acids compromise resin stability, TOFA was subjected to non-Kolbe decarboxylation to give alkenes upon loss of CO2. Thereby, the degree of unsaturation is significantly increased. This electrosynthetic protocol using an undivided cell setup and inexpensive graphite electrodes in a galvanostatic operation mode was scaled to a 1.5 L reactor, making use of electric current as a green and waste-free reagent. Simple, cost-efficient epoxidation using oxone subsequently gives an epoxy resin of low viscosity. Curing with anhydrides yields thermoset materials. Dynamic mechan…
Preliminary studies about thermal degradation of edible oils through attenuated total reflectance mid-infrared spectrometry
2009
Abstract Degradation of edible oils during their heating process has been evaluated through the determination of cis -unsaturation and trans -fatty acids together with free fatty acids as a function of time and temperature heating. Two types of cooking oils, sunflower and seed (mixture of different seeds non-detailed), were heated at three different temperatures (147, 171 and 189 °C) during a total time of 1920 min (32 h) shared out in four sessions of 8 h each one, and samples were studied from their spectra obtained by Fourier transform infrared spectrometry using attenuated total reflectance measurements. A critical comparison between different multivariate calibration models built based…
Determination of molecular species of oil triacylglycerols by reversed-phase and chiral-phase high-performance liquid chromatography
1991
A method is described for the determination of molecular species of oil triacylglycerols. The method is based on the analytical separation of the enantiomericsn-1,2-andsn-2,3-diacylglycerols, derived from triacylglycerols, by high-performance liquid-chromatography (HPLC) on a chiral column containing N-(R)-1-(α-naphthyl)ethylaminocarbonyl-(S)-valinecarbonyl-(S)-valine as stationary phase. Model triacyl-glycerol molecules comprising three known fatty acids were isolated from peanut oil and cottonseed oil by a combination of argentation-TLC and reversed-phase HPLC and submitted to partial chemical deacylation. The derivedsn-1,2(2,3)-diacylglycerols were analyzed and fractionated as 3,5-dinitr…
GW170817: Measurements of Neutron Star Radii and Equation of State
2018
On 17 August 2017, the LIGO and Virgo observatories made the first direct detection of gravitational waves from the coalescence of a neutron star binary system. The detection of this gravitational-wave signal, GW170817, offers a novel opportunity to directly probe the properties of matter at the extreme conditions found in the interior of these stars. The initial, minimal-assumption analysis of the LIGO and Virgo data placed constraints on the tidal effects of the coalescing bodies, which were then translated to constraints on neutron star radii. Here, we expand upon previous analyses by working under the hypothesis that both bodies were neutron stars that are described by the same equation…
Distribution and chemotaxonomic significance of acetylenic fatty acids in mosses of the dicranales
1987
Abstract Thirty-eight moss species from four families of the order Dicranales were analysed for the fatty acid composition of their acyl lipids. In the Ditrichaceae and the Dicranaceae numerous species were found to contain acetylenic fatty acids in their triglycerides, 9,12,15-Octadecatrien-6-ynoic acid was the major component, often accounting for more than 80 mol%, whereas 9,12-octadecadien-6-ynoic acid was found in small amounts of less than 5 mol%. In some genera, all the species examined contained acetylenic fatty acids, e.g. Dicranella and Dicranum , whereas in the genus Campylopus all five species tested were free of acetylenic compounds. Two genera, Ditrichum and Dicranoweisia , we…
Vegetable and Fruit Intakes Are Associated with hs-CRP Levels in Pre-Pubertal Girls
2017
The influence of diet on inflammation in children remains unclear. We aimed to analyze the influence of diet on high-sensitivity C-reactive protein (hs-CRP) levels in a pre-pubertal population free of other influences that may affect hs-CRP levels. We determined hs-CRP levels in 571 six- to eight-year-old children using an hs-CRP ELISA kit. Information on food and nutrient intake was obtained through a food-frequency questionnaire. Overall dietary quality was assessed using the Healthy Eating Index (HEI). We found that girls in the highest tertile of hs-CRP levels had a higher intake of saturated fatty acid, and lower intakes of fiber and vitamin E and a lower HEI score when compared to tho…
Fiber intake and all-cause mortality in the Prevención con Dieta Mediterránea (PREDIMED) study
2014
Background: Few observational studies have examined the effect of dietary fiber intake and fruit and vegetable consumption on total mortality and have reported inconsistent results. All of the studies have been conducted in the general population and typically used only a single assessment of diet. Objective: We investigated the association of fiber intake and whole-grain, fruit, and vegetable consumption with all-cause mortality in a Mediterranean cohort of elderly adults at high cardiovascular disease (CVD) risk by using repeated measurements of dietary information and taking into account the effect of a dietary intervention. Design: We followed up 7216 men (55-75 y old) and women (60-75 …
Skolēnu ar dzirdes traucējumiem iekļaušanas problēmas un risinājumi vispārizglītojošā skolā
2021
Bakalaura darbs ir izstrādāts par tēmu “Skolēnu ar dzirdes traucējumiem iekļaušanas problēmas un risinājumi vispārizglītojošā skolā”. Bakalaura darba autore: Jekaterina Dzinēja Darba izvēlētā temata aktualitāte pamatojama ar to, ka mūsdienās skolēni ar dzirdes traucējumiem tiek iekļauti vispārizglītojošajās skolās, pedagogi un vecāki sastopas ar dažāda rakstura problēmām iekļaujot skolēnus ar dzirdes traucējumiem vispārizglītojošajās skolās, tādēļ būtiski izpētīt intervējot skolotājus un vecākus kā var atrisināt šīs problēmas. Pētījuma mērķis: Veikt teorētisku un praktisku pētījumu par skolēnu ar dzirdes traucējumiem iekļaušanas vispārizglītojošajā skolā problēmām un to risinājumiem, izmant…