Filtry
wszystkich: 2203
wybranych: 2012
wyświetlamy 1000 najlepszych wyników Pomoc
Wyniki wyszukiwania dla: polyphenolic compounds
-
Vis-Responsive Copper-Modified Titania for Decomposition of Organic Compounds and Microorganisms
Publikacja -
Application of Coordination Compounds with Transition Metal Ions in the Chemical Industry—A Review
Publikacja -
Microwave plasma application in decomposition and steam reforming of model tar compounds
Publikacja -
Plasticized PVC Membrane Modified Electrodes: Voltammetry of Highly Hydrophobic Compounds
Publikacja -
Theoretical prediction of enthalpies and temperatures of sublimation of organochlorine compounds including pesticides
Publikacja -
Activity of TiO2 Photocatalyst Modified with H2WO4 for Degradation of Organic Compounds in Water
Publikacja -
Cross section calculations for electron scattering from platinum chemotherapeutic compounds
PublikacjaCross section for electron impact ionization of carboplatin, C6H12N2O4Pt, and oxaliplatin, C8H14N2O4Pt, have been calculated within binary-encounter-Bethe model for energies from the ionization threshold up to 5000 eV. Cross section for elastic electron scattering from carboplatin and oxaliplatin molecules have also been derived using independent atom method (IAM) and additivity rule for collision energies ranging from 50 eV to...
-
Removal of BTEX Compounds From Waste Gases; Destruction and Recovery Techniques
PublikacjaThe tendency for BTEX compounds (benzene, toluene, ethylbenzene, xylenes) to spread into all compartments of the environment together with their influence on both ecosystem and human health means that the emission of thesecompounds into the air is becoming the matter of worldwide concern. The legal regulations introduced by the European Union governing the assessment and management of air quality obliges member states to systematically...
-
Nutritional and Pharmaceutical Properties of Bioactive Compounds in Organic and Conventional Growing Kiwifruit
PublikacjaThe bioactivity of two kiwifruit’s cultivars growing under organic and conventional conditions were studied and compared. The bioactive compounds were extracted with water and ethanol using similar conditions which are applied in pharmaceutical applications and for daily fruit consumption such as tea drink. Antioxidant radical scavenging assays [ferric-reducing/antioxidant power (FRAP); cupric reducing antioxidant capacity (CUPRAC);...
-
The speciation of organotin compounds in sediment and water samples from the port of Gdynia
PublikacjaOrganotin compounds (OTC) are toxic towards all living organisms. The application of organitin-based antifouling systems is becoming the main source of OTC in the ocean. Harbor sediments and water contain large deposits of organotin compounds due to application of antifouling systems in the shipping industry. OTC contamination presents a potential risk to the marine environment. Sediment and water samples were collected in 2009...
-
Determination of Surfactants in Environmental Samples. Part III. Non-Ionic Compounds
PublikacjaNon-ionic surface active agents are a diverse group of chemicals which have an uncharged polar head and a non-polar tail. They have different properties due to amphiphilic structure of their molecules. Commercial available non-ionic surfactants consist of the broadest spectrum of compounds in comparison with other types of such agents. Typically, non-ionic compounds found applications in households and industry during formulation...
-
The role of the sawage treatment plant in the removal of genotoxic compounds from the environment
PublikacjaOne reason for increased incidence of various types of cancer are environmental pollutants particularly of anthropogenic origin. All human activities may pollute the environment, but some have significant impact, just to mention energy industry, mining, transportation, chemical and petrochemical industries and housing. Environmental pollutants are a large group of compounds in terms of their physicochemical properties, some of...
-
Coacervative extraction as a green technique for sample preparation for the analysis of organic compounds
PublikacjaOne of the present trends in analytical chemistry is miniaturization, which is one of the methods of green analytical chemistry application. A particular emphasis is placed on the elimination of the use of large amounts of organic solvents which are toxic and harmful to the environment, maintaining high efficiency of the extraction process, high recovery values and low values of quantification (LOQ) and detection (LOD) limits....
-
The II phase metabolism of endogenous and exogenous compounds, including antitumor chemotherapeutics
PublikacjaThe II phase metabolism, it is a set of metabolism and excretion pathways of endogenous as well as exogenous compounds including xenobiotics. UDP-glucuronyltransferases (UGTs; EC 2.4.1.17) are the most crucial representatives of II phase enzymes, which are responsible for the transformation of bilirubine and bile acids, steroids and thyroid hormones and lipids. Exogenous compounds, including drugs, carcinogens, environmental pollutants...
-
Green sample preparation techniques for chromatographic determination of small organic compounds
PublikacjaAccurate monitoring of the state of the environment requires the introduction of additional isolation and/or preconcentration step prior to the chromatographic determination. In this work the information about novel methodological and instrumental solutions in relation to different variants of microextraction techniques are presented. Attention is focused on analytical procedure and suitable analytical tools for extraction of the...
-
Phytoecdysteroid containing plants – a source of bioactive compounds with potential anticarcinogenic effects
PublikacjaEcdysteroids are a group of steroids synthesized in inver- tebrates as molting hormones and also in some plants as secondary metabolites acting as a defense against parasites. These compounds do not naturally occur in mammals and are not structurally related to mammalian steroid hor- mones, consequently do not activate mammalian hormone receptors. Ecdysteroids exhibit very low toxicity to mam- mals and to date no serious side effects...
-
In-tube extraction for the determination of the main volatile compounds in Physalis peruviana L
PublikacjaAn analytical procedure based on in-tube extraction followed by gas chromatography with mass spectrometry has been developed for the analysis of 24 main volatile components in cape gooseberry (Physalis peruviana L.) samples. According to their chemical structure, the compounds were organized into different groups: one hydrocarbon, one aldehyde, four alcohols, four esters, and 14 monoterpenes. By single-factor experiments, incubation...
-
Preliminary Results from the Removal of Phosphorus Compounds with Selected Sorption Material
PublikacjaDue to the resources of phosphorous are limited and are exhausted in the next 30 years the management of the resources is become current issue. Most of the phosphorus compounds is lost forever, because it is discharged with sewage into surface waters, causing eutrophication and in this way causing a further problem and challenge. On the other hand, there is a considerable need for phosphorus compounds, primarily in bioavailable...
-
Analytical methods and problems related to the determination of organotin compounds in marine sediments
PublikacjaProcedury analityczne oznaczania zwiazków cynoorganicznych w osadach morskich skladają się z wilu operacji i czynnosci (pobieranie próbek, wstępne przygotowanie, transport, oznaczenia końcowe). Zazwyczaj procedury te charakteryzują się dużą praco- i czasochłonnością. W pracy omówiono podstawowe źródła błędów zwiazane z w/wym etapami postepowania analitycznego oraz przedstawiono sposoby im zapobiegania.
-
Quality problems in determination of organic compounds in environmental samples, such as PAHs and PCBs
Publikacja -
Speciation of trace element compounds in samples of biota from marine ecosystems
Publikacja -
Supercritical Algal Extracts: A Source of Biologically Active Compounds from Nature
Publikacja -
Structural and electronic properties of some intriguing (rare-earth)Ba2Cu3O7 compounds.
PublikacjaW rozdziale przedstawiono przegląd wyników eksperymentalnych i teoretycznych dotyczących wybranych związków o wzorze (lantanowiec)Ba2Cu3O7 wykazujących całkowicie odmienne właściwości w porównaniu z całą klasą nadprzewodzących związków tlenkowych o stechiometrii 1:2:3. Szczególny nacisk położono na analizę procesu wzrostu kryształów i powstawania defektów punktowych determinujących późniejsze własności fizyczne tych materiałów....
-
Non-regulated organic compounds (NROC's) in the Odra River water samples.
PublikacjaW ramach badań opisanych w pracy podjęto próbę identyfikacji lotnych i średniolotnych związków z grupy Non-Regulated Organic Compounds obecnych w próbkach wody rzecznej. Analizie poddano 25 próbek wód pobranych z rzeki Odry w październiku 2000, w trakcie VIII kampanii zorganizowanej w ramach International Odra Project (IOP). W badaniach wykorzystano technikę PT-TD-GC-MS.Komputerowa analiza widm masowych wykazała obecność wielu...
-
Quality problems in the determination of organic compounds in environmental samples, such as PAHs and PCBs
PublikacjaPrzedstawiono i skomentowano wyniki badań międzylaboratoryjnych w zakresie oznaczania wybranych związków organicznych w próbkach środowiskowych. Oznaczenia wykonane były przez niezależne laboratoria analityczne, które stosowały różne procedury przygotowania próbek do analizy.Badania wskazują, że wynik oznaczania poszczególnych analitów zależny był od stosowanej przez laboratorium procedury izolacji i oznaczania. Stwierdzono różnice...
-
Application of electrochemical sensors and sensor matrixes for measurement of odorous chemical compounds
PublikacjaIn this paper describes the principle of operation of the electrochemical sensors and the sensor matrixes comprised of electrochemical sensors intended for measurement of odorous compounds. Critical comparison of these sensors’ advantages and disadvantages has been made. The fields of economy contributing to release of odours and the potential sources of their emission have been identified. Commercially available electrochemical...
-
Degradacja związków organicznych w środowisku. Degradation of organic compounds in the environment
PublikacjaZwiązki organiczne w zależności od elementu środowiska, w jakim występują (gleba, osady denne, wody powierzchniowe i gruntowe), mogą ulegać - pod wpływem rozmaitych procesów chemicznych, fizycznych, biologicznych czy też foto-chemicznych - różnorakim przemianom. Przedstawiono drogi degradacji wybranych trwałych zanieczyszczeń organicznych w różnych warunkach. Omówiono problem pojawiania się produktów pośrednich w czasie degradacji...
-
Impact of high-pressure processing on the bioactive compounds of milk - A comprehensive review
PublikacjaHigh-pressure processing (HPP) is a promising alternative to thermal pasteurization. Recent studies highlighted the effectivity of HPP (400–600 MPa and exposure times of 1–5 min) in reducing pathogenic microflora for up to 5 logs. Analysis of modern scientific sources has shown that pressure affects the main components of milk including fat globules, lactose, casein micelles. The behavior of whey proteins under HPP is very important...
-
Biologically active compounds based on the carbazole scaffold - synthetic and mechanistic aspects
PublikacjaDoctoral dissertation is divided into three main parts: introduction, results and discussion and experimental. The introduction is divided into four main parts which describe: 5-hydroxytryptamine receptors, the most popular antidepressants, new compounds based on the carbazole structure with affinity for serotonin receptors, telomeres and telomerase with their functions, telomerase inhibition strategies, carbazoles approved in...
-
Are Titania Photocatalysts and Titanium Implants Safe? Review on the Toxicity of Titanium Compounds
Publikacja -
Formation of environmentally friendly chloroorganic compounds technology by sewage and by-products utilization
Publikacja -
Microanalysis of volatile organic compounds (VOCs) in water samples - methods and instruments
PublikacjaW pracy przedstawiono stan wiedzy nt. metodyk analitycznych oraz urządzeń kontrolno-pomiarowych, wykorzystywanych w badaniach próbek wody na zawartość lotnych związków organicznych. Szczególną uwagę zwrócono na techniki izolacji i wzbogacania analitów przed etapem oznaczeń końcowych.
-
Endocrine disrupting compounds in the baby's world - A harmful environment to the health of babies
PublikacjaGlobally, there has been a significant increase in awareness of the adverse effects of chemicals with known or suspected endocrine-acting properties on human health. Human exposure to endocrine disrupting compounds (EDCs) mainly occurs by ingestion and to some extent by inhalation and dermal uptake. Although it is difficult to assess the full impact of human exposure to EDCs, it is well known that timing of exposure is of importance...
-
The Mechanism of the Osteoprotective Action of a Polyphenol-Rich Aronia melanocarpa Extract during Chronic Exposure to Cadmium is Mediated by the Oxidative Defense System
Publikacja -
The influence of different time durations of thermal processing on berries quality
PublikacjaBioactive compounds (polyphenols, flavonoids, flavanols, tannins, anthocyanins and ascorbic acid) and the level of antioxidant activity by ABTS, DPPH, FRAP and CUPRAC of water, acetone and hexane extracts of Chilean 'Murtilla' (Ugni molinae Turcz) and 'Myrteola' berries (Myrtaceae, Myrteola nummularia (Poiret) Berg.), Chilean and Polish blueberries (Vaccinium corymbosum), Chilean raspberries (Rubus idaeus), and Polish black chokeberry...
-
SURFACTANTS IN KLODNICA RIVER (KATOWICE, POLAND). PART II. QUATERNARY AMMONIUM COMPOUNDS
PublikacjaThe paper presents methods of determination of analytes of the cation group (alkyl benzyl dimethyl ammonium (BDDA-C12-C16), alkyl trimethyl ammonium (TMA), hexadecyl piridinium (HP)) in surface water and bottom sediment samples. In the sample preparation phase the solid phase extraction (SPE) or accelerated solvent extraction/ultrasound assisted extraction (ASE/UAE)-SPE technique was used and in the identification phase and quantitative...
-
Comparison of the contents of bioactive compounds and the level of antioxidant activity in different kiwifruit cultivars
PublikacjaGłównym celem prowadzonych badań było stwierdzenie która z odmian owoców kiwi (''Hayward'', ''Daeheuhg'', ''Haenam'' oraz ''Bidan'') jest najbardziej odpowiednią z punktu widzenia konsumpcji przez człowieka. Z tego powodu w odpowiednio przygotowanych próbkach ekstraktów z owoców kiwi oznaczono:- profile związków bioaktywnych;- poziomy aktywności przeciwutleniającej. Wyniki pomiarów zawartości polifenoli (flawonoidy oraz kwasy fenolowe)...
-
Removal of organic compounds from water by solvent sublation. Criteria for solvent selection.
PublikacjaProces flotoekstrakcji zastosowano do usuwania z wody następujących związków organicznych: tetrachlorku węgla, chloroformu, 1,3,5-trimetylobenzenu (mezytylenu), fenolu i 2,4,5-trichlorofenolu. Jako odbierające fazy organiczne użyto: olej mineralny, 1-dekanol, 1-oktanol, octan amylu, dodekan i tetradekan. Mechanizmem decydującym o usuwaniu lotnych związków organicznych (VOC) było odparowanie do wnętrza pęcherzyków gazu, podczas...
-
Cold-modulated leaf compounds in winter triticale DH lines tolerant to freezing and
Publikacja -
Advanced oxidation processes for recalcitrant compounds removal comparison with biofiltration by Corbicula fluminea
Publikacja -
Nitrobenzimidazoles as Substrates for DT-Diaphorase and Redox Cycling Compounds: Their Enzymatic Reactions and Cytotoxicity
Publikacja -
Bioactive Compounds of Blueberries: Post-Harvest Factors Influencing the Nutritional Value of Products
Publikacja -
Chirality sensing of bioactive compounds with amino alcohol unit via circular dichroism
Publikacja -
Improvement of charge separation in TiO 2 by its modification with different tungsten compounds
Publikacja -
Rearrangement of azoxybenzocrowns into chromophoric hydroxyazobenzocrowns and the use of hydroxyazobenzocrowns for the synthesis of ionophoric biscrown compounds
PublikacjaThe Wallach rearrangement was used as a method for preparing p-hydroxyazobenzocrown ethers starting from different azoxybenzocrowns as substrates. Synthesis of a series of p-hydroxyazobenzocrowns under modified conditions and characterization of the obtained products are presented. o-Hydroxyazobenzocrowns were identified among the products of the photochemical rearrangement of azoxybenzocrowns. Novel biscrowns were synthesized...
-
Microextraction Techniques Used in the Procedures for Determining Organomercury and Organotin Compounds in Environmental Samples
PublikacjaDue to human activities, the concentrations of organometallic compounds in all parts of the environment have increased in recent decades. The toxicity and some biochemical properties of mercury and tin present in the environment depend on the concentration and chemical form of these two elements. The ever-increasing demand for determining compounds at very low concentration levels in samples with complex matrices requires...
-
Organomercury compounds in environmental samples: emission sources, toxicity, environmental fate and determination.
PublikacjaIn view of the specific properties of mercury and its capability of forming compounds that can be bioaccumulated and biomagnified at successive levels of the trophic pyramid, it has become necessary to gather detailed information on the sources of emission of this element into the environment and its fate there. Moreover, the increasing awareness of the relationship between the toxicity of mercury and its chemical form has sharpened...
-
Miniaturized passive emission test chamber for in-situ measurement of emissions of organic compounds
PublikacjaThe results of many different studies have demonstrated unequivocally that the quality of indoor air is often much worse than that of atmospheric air (outdoor). One of the main groups of chemical compounds present in indoor air, with proven harmfulness to health,are volatile organic compounds (VOCs). VOCs present indoor comprise a wide variety of hydrocarbons and hydrocarbons derivatives including aliphatic, aromatics, alkylbenzens,...
-
Influence of composition of raw wastewater on removal of nitrogen compounds in multistage treatment wetlands
PublikacjaInfluence of composition of raw wastewater on the efficiency of organic matter and nitrogen removal in multistage treatment wetlands has been examined. Commonly used indicators, like COD/BOD5 and BOD5/TN ratio, determining wastewater susceptibility to biodegradation in conventional treatment technologies were assessed. It was confirmed that multistage treatment wetland may be used for treatment of wastewater with high loads of...
-
Characteristics of volatile organic compounds emission profiles from hot road bitumens
PublikacjaA procedure for the investigation and comparison of volatile organic compounds (VOCs) emission profiles to the atmosphere from road bitumens with various degrees of oxidation is proposed. The procedure makes use of headspace analysis and gas chromatography with universal as well as selective detection, including gas chromatography–mass spectrometry (GC–MS). The studies revealed that so-called vacuum residue, which is the main component...