Search results for "fenolit"
showing 10 items of 12 documents
Successful aerobic bioremediation of groundwater contaminated with higher chlorinated phenols by indigenous degrader bacteria
2018
The xenobiotic priority pollutant pentachlorophenol has been used as a timber preservative in a polychlorophenol bulk synthesis product containing also tetrachlorophenol and trichlorophenol. Highly soluble chlorophenol salts have leaked into groundwater, causing severe contamination of large aquifers. Natural attenuation of higher-chlorinated phenols (HCPs: pentachlorophenol + tetrachlorophenol) at historically polluted sites has been inefficient, but a 4-year full scale in situ biostimulation of a chlorophenol-contaminated aquifer by circulation and re-infiltration of aerated groundwater was remarkably successful: pentachlorophenol decreased from 400 μg L−1 to <1 μg L−1 and tetrachlorophen…
Oxidovanadium(v) complexes with l-proline-based amino acid phenolates
2019
L-proline was used to prepare chiral, tridentate amino acid phenol proligands H2L1—4. These proligands react with vanadium precursors VO(acac)2, VOSO4 ∙ 5 H2O and VO(OPr)3 in methanol to form the corresponding oxidoalkoxidovanadium(V) complexes 1—4. The complexes crystallize from methanol, and are octahedrally coordinated with a general formula [VO(L1—4)(OMe)(MeOH)]. In solution, however, they adopt several different conformations or isomeric structures depending on the solvent. peerReviewed
Enzyme-assisted extraction of anthocyanins and other phenolic compounds from blackcurrant (Ribes nigrum L.) press cake: From processing to bioactivit…
2022
The effects of commercial enzymes (pectinases, cellulases, beta-1-3-glucanases, and pectin lyases) on the recovery of anthocyanins and polyphenols from blackcurrant press cake were studied considering two solid:solvent ratios (1:10 and 1:4 w/v). β-glucanase enabled the recovery of the highest total phenolic content – 1142 mg/100 g, and the extraction of anthocyanins was similar using all enzymes (∼400 mg/100 g). The use of cellulases and pectinases enhanced the extraction of antioxidants (DPPH − 1080 mg/100 g; CUPRAC – 3697 mg/100 g). The freeze-dried extracts presented antioxidant potential (CUPRAC, DPPH), which was associated with their biological effects in different systems: antiviral a…
Ympäristöestrogeeniseoksen yhteisvaikutus 20dpfZF-seeprakalan vitellogeniinigeenin ilmentymiseen
2011
Ihmisten toimesta ympäristöön joutuvien vierasaineiden vaikutukset hormonitoimintaan ovat viime vuosina herättäneet paljon keskustelua. Yksi alan tutkituimmista aihealueista on estrogeenin kaltaisesti vaikuttavien aineiden eli ympäristöestrogeenien aiheuttamat lisääntymis- ja kehityshäiriöt. Estrogeenisiä vaikutuksia voidaan tutkia monella tapaa, alkaen solutason vasteista populaatiokehitykseen. Yksi paljon käytetty molekyylimarkkeri on kalojen vitellogeniinitason mittaus. Vaikka normaalioloissa vain naaraat tuottavat vitellogeniiniä, estrogeenialtistuksen vaikutuksesta myös koiraat ja nuoret yksilöt voivat sitä tuottaa. Tässä opinnäytetyössä tutkittiin kolmen ympäristöestrogeenin, bisfenol…
Syntheses, characterization and properties of Cu(II)-, Mo(VI)- and U(VI) complexes with diaminotetraphenolate ligands
2013
Oxidovanadium(v) complexes with l-proline-based amino acid phenolates
2019
Abstract l -proline was used to prepare chiral, tridentate amino acid phenol proligands H2L1–4. These proligands react with vanadium precursors VO(acac)2, VOSO4∙5H2O and VO(OPr)3 in methanol to form the corresponding oxidoalkoxidovanadium( v ) complexes 1–4. The complexes crystallize from methanol, and are octahedrally coordinated with a general formula [VO(L1–4)(OMe)(MeOH)]. In solution, however, they adopt several different conformations or isomeric structures depending on the solvent.
Valorization potential of technical lignins from Norway spruce (Picea abies) via pyrolysis
2022
Analytical pyrolysis (Py-GC/MS) on mg-scale of Norway spruce (Picea abies)-derived kraft lignin, ethanosolv lignin, and dried lignin-rich soda-anthraquinone (AQ) black liquors was studied at 500 °C to compare the valorization potential of these materials, focusing on the type and yield of condensable pyrolysis products. Of particular interest was the relatively selective formation of guaiacol (2-methoxyphenol) from the dried soda-AQ black liquors in contrast to the formation of complex phenolic product mixtures from the pyrolysis of the kraft and ethanosolv lignins. It was shown that this finding could be attributed to differences in composition and structure as was assessed by various NMR …
Kloorifenoleilla pilaantuneen maan kompostointi : biotestien käyttö kompostoinnin onnistumisen seurannassa
2008
Ligniinin osuuden vaikutus ligniini-fenoliformaldehydihartsien kemiaan
2017
Fenoliformaldehydihartsia valmistetaan fenolista ja formaldehydistä, joka toimii ristisilloitusagenttina. Katalyyttinä käytetään natriumhydroksidia. Formaldehydi liittyy fenolin renkaaseen hydroksyyliryhmän para- tai orto-asemiin additioreaktiolla alkalisissa olosuhteissa. Fenolin alkalointi saa aikaa renkaaseen karbanioneja, joihin formaldehydin elektrofiilinen hiiliatomi voi liittyä. Reaktio tunnetaan Lederer-Manasse-reaktiona. Ligniini on amorfinen biopolymeeri, jota saadaan esimerkiksi sulfaattiprosessin sivutuotteena. Rakenteellisesti ligniinistä voidaan erottaa kolme fenyylipropaaniyksikköä, jotka ovat p-kumaryylialkoholi, koniferyylialkoholi ja sinapyylialkoholi. Ligniinillä voidaan …