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Wyniki wyszukiwania dla: BTEX COMPOUNDS
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Antimicrobial Activities of Compounds Produced by Newly Isolated Streptomyces Strains from Mountain Caves
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Possibilities of Phoslock® application to remove phosphorus compounds from wastewater treated in hybrid wetlands
PublikacjaTreatment wetland technologies for wastewater treatment can be easily applied for removal of all pollutants except phosphorous. They are applicable in a small towns and rural areas, places where conventional wastewater treatment plant cannot properly operate because of common economic constraints. In Poland only the 8% of rural areas are equipped with sewer system, thus treatment wetlands might be an alternative, effective and...
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Methods of assaying volatile oxygenated organic compounds in effluent samples by gas chromatography—A review
PublikacjaThe paper is a review of the procedures for the determination of volatile and semivolatile oxygenated organic compounds (O-VOCs) in effluent samples by gas chromatography. Current trends and outlook for individual steps of the procedure for the determination of O-VOCs in effluents are discussed. The available sample preparation techniques and their limitations are described along with GC capillary columns used for O-VOCs separation...
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Highly effective asphaltene-derived adsorbents for gas phase removal of volatile organic compounds
PublikacjaA novel nitrated asphaltene-derived adsorbent (Asf-Nitro) was prepared using facile isolation and modification procedures. The successful modification was confirmed by Fourier-transform infrared spectroscopy (FTIR). The nitrated adsorbent was evaluated in terms of dispersive and specific interactions, Lewis acid-base properties and adsorption isotherms by means of inverse gas chromatography (IGC). Nitration was found to be extremely...
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The use of various species of fungi in biofiltration of air contaminated with odorous volatile organic compounds
PublikacjaAir pollution with odorous compounds is a significant social and environmental problem. This paper presents biological deodorization methods. The attention is focused on the application of biotrickling filters for air deodorization. Principles of their operation are discussed, indicating the key role of the selection of microorganisms responsible for the degradation of odorous compounds. A literature overview of the used fungal...
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Crossover from charge density wave stabilized antiferromagnetism to superconductivity in Nd1−xLaxNiC2 compounds
PublikacjaThe path from the charge density wave antiferromagnet NdNiC2 to the noncentrosymmetric superconductor LaNiC2 is studied by gradual replacement of Nd by La ions. The evolution of physical properties is explored by structural, magnetic, transport, magnetoresistance, and specific heat measurements. With the substitution of La for Nd, the Peierls temperature is gradually suppressed, which falls within the BCS mean-field relation for...
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Investigation of Air Quality beside a Municipal Landfill: The Fate of Malodour Compounds as a Model VOC
PublikacjaThis paper presents the results of an investigation on ambient air odour quality in the vicinity of a municipal landfill. The investigations were carried out during the spring–winter and the spring seasons using two types of the electronic nose instrument. The field olfactometers were employed to determine the mean odour concentration, which was from 2.1 to 32.2 ou/m3 depending on the measurement site and season of the year. In...
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Ab initio and density functional theory calculations of proton affinities for volatile organic compounds
PublikacjaThe Hatree-Fock method with 6-311G** split-valence molecular orbitals basis sets and the density function theory-B3LYP have been applied to geometrical optimizations and calculations of total electronic, zero point vibrational energies and proton affinities at 298 K for volatile organic compounds. Calculated values of proton affinities are compared with experimental data.
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Assessment of Lipophilicity Indices Derived from Retention Behavior of Antioxidant Compounds in RP-HPLC
PublikacjaReverse phase high pressure liquid chromatography was employed in order to evaluate the lipophilicity of antioxidant compounds from different classes, such as phenolic acids, flavanones, flavanols, flavones, anthocyanins, stilbenes, xantonoids, and proanthocyanidins. The retention time of each compound was measured using five different HPLC columns: RP18 (LiChroCART, Purosphere RP-18e), C8 (Zorbax, Eclipse XDBC8), C16-Amide (Discovery...
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New procedure for the examination of the degradation of volatile organonitrogen compounds during the treatment of industrial effluents
PublikacjaWe present a new procedure for the determination of 32 volatile organonitrogen compounds in samples of industrial effluents with a complex matrix. The procedure, based on dispersive liquid–liquid microex-traction followed by gas chromatography with nitrogen-phosphorus and mass spectrometric detection, wasoptimized and validated. Optimization of the extraction included the type of extraction and disperser sol-vent, disperser solvent...
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Bacterial presence in polar regions associated with environment modification by chemical compounds including contaminants
PublikacjaMicrobes are omnipresent and diverse members of all biological communities. In marine and freshwater ecosystems, microorganisms form the base of the food chain supporting higher trophic levels. Even though, microbes generally are thought to live in warm regions of Earth, many of them develop in cold climates. Polar regions remain relatively protected from widespread anthropogenic disturbances, which is a consequence of its remoteness...
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Application of cyanated asphaltenes in gas-phase adsorption processes for removal of volatile organic compounds
PublikacjaThe paper presents an innovative, chemically modified (methylcyanated) asphaltene-based adsorbent that can be an inter-esting low-cost alternative for traditional adsorbents. Adsorption properties of adsorbents were examined by inverse gas chromatography technique, adsorption isotherms, and breakthrough curves. A significant increase in retention volume for pyridine, 2-pentanone, nitropropane, toluene, and 1-butanol was observed....
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The dynamic of processes responsible for transformation of nitrogen compounds in hybrid wetlands systems in a temperate climate.
PublikacjaAnalizowano ilościowe i jakościowe przemiany związków azotu po poszczególnych stopniach oczyszczania w hybrydowych systemach hydrofitowych w Wiklinie i Sarbsku.
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An attempt to identify volatile and semi-volatile organic compounds present in the Odra river waters.
PublikacjaCelem pracy była identyfikacja związków z grup lotnych i średniolotnych związkó organicznych. W badaniach wykorzystano technikę Pt-TD-GC-MS. Komputerowa analiza widm masowych wykazała obecność wielu związków organicznych pochodxenia naturalnego i antropogenicznego. W powłokach wód pobranych w okolicy Brzegu Dolnego oznaczono stężenia związków chloroorganicznych na poziomie pojedynczych prób. Nieco wyższe spektrum związków chloroorganicznych,...
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Determination of volatile organohalogen compounds in urban precipitation in Tricity area (Gdańsk, Gdynia, Sopot).
PublikacjaPróbki opadów atmosferycznych pobierano w 4 punktach na terenie Gdańska i Sopotu, od listopada 2000 do maja 2001. Oznaczano chloro- i bromopochodne metanu, etanu i etenu. Lotne związki chlorowcoorganiczne oznaczane były metodą bezpośredniego nastrzyku próbki wody do kolumny kapilarnej z wykorzystaniem detektora wychwytu elektronów na etapie detekcji (DAI-GC-ECD). Najczęściej oznaczanymi związkami na wszystkich stacjach pobierania...
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The importance of degradation in the fate of selected organic compounds in the environment. Part II. Photodegradation and biodegradation
PublikacjaDegradacja jest naturalnym, wszechobecnym procesem rozkładu substancji organicznych obecnych w środowisku. Produkty degradacji lub pośrednie produkty rozkładu związków organicznych często wykazują inną toksyczność w stosunku do mikroorganizmów, zwierząt i ludzi niż związki wyjściowe. Procesy fotodegradacji i biodegradacji zachodzą zwykle jednocześnie. Fotodegradacja uznawana jest za wstępny proces, po którym następuje rozkład...
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The importance of degradation in the fate of selected organic compounds in the environment. Part. I. General considerations.
PublikacjaZwiązki organiczne, w zależności od elementu środowiska w jakim występują (gleba, osady denne, wody powierzzchniowe i gruntowe) mogą ulegać powolnym przemianom pod wpływem rozmaitych procesów fizycznych, chemicznych biologicznych czy też fotochemicznych. W pracy przedstawiono drogę degradacji wybranych trwałych zanieczyszczeń organicznych w różnych warunkach. Omówiono problem pojawiania się produktów pośrednich w czasie degradacji...
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Development and evaluation of headspace gas chromatography method for the analysis of carbonyl compounds in spirits and vodkas
PublikacjaPrzedstawiono wyniki oznaczania związków karbonylowych (po przeprowadzeniu w pochodne przy użyciu odczynnika derywatyzującego - o-PFBHA) przy wykorzystaniu techniki analizy fazy nadpowierzchniowej w połączeniu z chromatografią gazową i detektorem wychwytu elektronów(ECD). Przedstawiono optymalizację metodyki oraz wyniki uzyskane podczas próbek rzeczywistych wybranych wyrobów spirytusowych.
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AlF4 superhalogen as the trigger-compound initiating the radical-substitution reactions
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Characteristics of the s–Wave Symmetry Superconducting State in the BaGe3 Compound
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Rich magnetic phase diagram in the Kagome-staircase compound Mn3V2O8
PublikacjaNa podstawie pomiarów podatności magnetycznej i ciepła właściwego monokryształu Mn3V2O8 skonstruowano diagram fazowy. Właściwości magnetyczne związku są silnie anizotropowe.
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Antiferromagnetism and mixed valency in the new Kondo lattice compound Ce3Rh4Sn7
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Crystal structure and physical properties of a novel ternary compound La15MoxGe9
PublikacjaWe present the synthesis, structural characterization and physical properties measurements of a new compound, La15MoxGe9 in Mn5Si3-type derived structure with interstitial Mo. The sample was synthesized by arc-melting method. La15MoxGe9 crystallizes in non-centrosymmetric hexagonal structure P63mc (#186) with lattice parameters a = b = 15.495(5) Å and c = 6.917(2) Å. The refinement on single X-ray diffraction data show that interstitial...
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Purification of model biogas from toluene using deep eutectic solvents
PublikacjaBiogas from landfills and wastewater treatment facilities typically contain a wide range of volatile organic compounds (VOCs), that can cause severe operational problems when biogas is used as fuel. Among the contaminants commonly occur aromatic compounds, i.e. benzene, ethylbenzene, toluene and xylenes (BTEX). In order to remove BTEX from biogas, different processes can be used. A promising process for VOCs removal is their absorption...
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SOLUBILIZATION OF BENZENE, TOLUENE, AND XYLENE (BTX) IN AQUEOUS MICELLAR SOLUTIONS OF AMPHIPHILIC IMIDAZOLIUM IONIC LIQUIDS
PublikacjaRozpuszczalne w wodzie ciecze jonowe wykazują aktywność powierzchniową oraz zdolność do tworzenia zorganizowanych struktur w roztworach wodnych. W pracy przedstawiono zdolność wodnych układów micelarnych chlorków 1-alkilo-3-metyloimidazoliowych do zwiększania rozpuszczalności węglowodorów aromatycznych – benzenu, toluenu i ksylenu. Zaobserwowano, że po przekroczeniu krytycznego stężenia micelizacji cieczy jonowych w wodzie, następuje...
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New lanthanide–CB[6] coordination compounds: relationships between the crystal structure and luminescent properties
PublikacjaThe reaction between cucurbit[6]uril (CB[6]) and lanthanide chlorides (Eu, Sm, Tb and Tm) in acidic aqueous media led to four new structures. The compounds obtained are isostructural with general formula [Ln2(H2O)12(H2O@CB[6])]Cl6(H2O)4 (Ln = Eu3+ (1), Sm3+ (2), Tb3+ (3) and Tm3+ (4)) and crystallize in the P21/c space group. For the complexes with Eu3+, Sm3+ and Tb3+, the luminescent properties in the solid state and aqueous media...
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Modeling hydrolysis of slowly biodegradable organic compounds in biological nutrient removal activated sludge systems
PublikacjaHydrolysis is an important process in biological wastewater treatment and is known to be the ratelimiting step in organic carbon removal from municipal or industrial wastewater. The influence of the readily biodegradable chemical oxygen demand fraction in biological wastewater treatment systems has been extensively investigated, but little is known about the effects of slowly biodegradable substrate (XS) on denitrification and...
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IDENTIFICATION OF ODOR OF VOLATILE ORGANIC COMPOUNDS USING CLASSICAL SENSORY ANALYSIS AND ELECTRONIC NOSE TECHNIQUE
PublikacjaThe paper compares two methods of analysis of odour of volatile organic compounds: classical sensory analysis and electronic nose technique. Eight volunteers participated in the classical sensory analysis investigations, which lasted two weeks. An instrumental odour analysis involved a prototype of 6-sensor electronic nose designed by the authors. The research performed with this device provided higher reproducibility and reliability...
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Metal-coated fused silica fibers as a support for immobilized compounds yielding a volatile analyte (C2H4)
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On practical problems in estimation of antioxidant activity of compounds by DPPH method (Problems in estimation of antioxidant activity)
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The role of colloidal and particulate organic compounds in idenitrification and EBPR occurring in a full-scale activatedsludge system
PublikacjaThe aim of this study was to determine the immediate effects of slowly biodegradable substrates on the denitrification capability andphosphate release/uptake interactions for a full-scale biomass process from the ''Wschod'' wastewater treatment plant (WWTP) in Gdansk (Poland). Since it is hard to distinguish the slowlybiodegradable substrate in a direct way, a novel procedure based on batch experiments was developed and implemented....
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Seasonal changes in organotin compounds in water and sediment samples from the semi-closed Port of Gdynia
PublikacjaThe effect of seasonal changes on the distribution of organotin compounds (OTC) in the sediments and seawaterfrom the docks of the Port of Gdynia was investigated. Sediment and seawater samples were collectedfrom four industrial docks in February (winter) and June (summer) in 2009. The samples were analyzed forbutyltin, phenyltin, octyltin, and tricyclohexyltin (total of 9 OTC derivatives). The fine fraction (b0.063 mm)accumulated...
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Monitoring of volatile organic compounds (VOCs) in atmospheric air. Part I. On-line gas analyzers
PublikacjaThe paper reviews the subject literature concerning the analytical instruments routinely used for monitoring volatile organic compounds in atmospheric air. The analyzers are classified as stationary or mobile according to their ease of transport. Stationary DOAS (Differential Optical Absorption Spectroscopy) analyzer is characterized, as are MIMS (Membrane Introduction Mass Spectrometry), MESI (Membrane Extraction with Sorbent...
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Monitoring of volatile organic compounds (VOCs) in atmospheric air. Part II. Sample collection and preparation
PublikacjaThe paper reviews literature information on air sampling techniques commonly used for monitoring volatile organic compounds (VOCs) levels in atmospheric air. It describes containers for collecting samples of atmospheric air, such as vacuum canisters and bags made from synthetic materials. It discusses dynamic, passive and denudational techniques for sampling analytes from air combining isolation with preliminary enrichment, and...
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The role of biodegradable particulate and colloidal organic compounds in biological nutrient removal activated sludge systems
PublikacjaThe efficiency of denitrification and enhanced biological phosphorus removal in biological nutrient removal activated sludge systems is strongly dependent on the availability of appropriate carbon sources. Due to high costs of commercial compounds (such as methanol, ethanol, acetic acid, etc.) and acclimation periods (usually) required, the effective use of internal substrates is preferred. The aim of this study was to determine...
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Determination of Volatile Organic Compounds in Indoor Air in the Gdansk Area Using Permeation Passive Samplers
PublikacjaPassive dosimetry — known for over a hundred years — is still a useful tool in monitoring air pollutants. In this work, permeation passive samplers were used to determine indoor air quality in 22 apartments located in the Gdansk area in the northern part of Poland. The results obtained by the passive sampling technique were compared to those obtained by dynamic sampling. Attempts were also made to identify indoor sources of...
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Studies on the orientation effect of crystallites and its application to cocrystal screening of selected pharmacologically active compounds
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Selective inhibition of cancer cells' proliferation by compounds included in extracts from Baltic Sea cyanobacteria
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Volatile organic compounds in gastrointestinal stromal tumour tissue originating from patient-derived xenografts
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Antiplasmodial Activity of Nitroaromatic and Quinoidal Compounds: Redox Potential vs Inhibition of Erythrocyte Glutathione Reductase
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Solid phase microextraction combined with chromatography - a powerful tool for determination of warfare agents and related compounds
PublikacjaOpisano zastosowanie mikroekstrakcji do fazy stacjonarnej do izolacji wzbogacania środków bojowych i produktów ich degradacji w powietrzu, wodzie i glebie oraz próbkach bilogicznych. Na etapie oznaczeń końcowych stosuje się najczęściej chromatografię gazową. Anality można pobierać przez bezpośrednie zanurzenie włókna w próbce ciekłej i gazowej oraz w fazie nadpowierzchniowej. Stosując SPME-GC można osiągnąć niskie granice oznaczalności...
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Metal-coated fused silica fibres as a support for immobilized compounds yielding a volatile analyte (C2H4)
PublikacjaPrzedstawiono wyniki badań dotyczących wykorzystania chemicznie modyfikowanych włókien szklanych pokrytych warstwą metalu (aluminium), jako nośników związków powierzchniowych. W trakcie procesu termicznego rozkładu z tak zmodyfikowanych włókien uwalnia się eten, który stanowi składnik mierzony uzyskiwanej gazowej mieszaniny wzorcowej. Ilość uwalnianego etenu zależy jedynie od długości danego rodzaju i typu modyfikowanego włókna...
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Carbon-encapsulated iron nanoparticles with deposited Pd: A high-performance catalyst for hydrogenation of nitro compounds
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Supercritical fluid extraction of algae enhances levels of biologically active compounds promoting plant growth
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Comparison of the main bioactive compounds and antioxidants in garlic and white and red onion after treatment protocols
PublikacjaPolski czosnek, biała i czerwona cebula była blanszowana, gotowana, smażona i poddawana działaniom promieniowania mikrofalowego. Następnie były w nich oznaczane m.in. takie związki jak polifenole, flawonoidy, kwas ascorbinowy i aktywne antyoksydanty. Udowodniono, że blanszowanie, smażenie i poddawanie działaniu promieniowania mikrofalowego nie wpływa znacząco na zmiejszenie zawartości badanych związków w czosnku i cebuli. Wyznaczono...
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Sample preparation for gas chromatographic determination of halogenated volatile organic compounds in environmental and biological samples
PublikacjaPodstawowym elementem przygotowania próbek środowiskowych i biologicznych do analizy jest etap izolacji i/lub wzbogacania polegający na przeniesieniu analitów z matrycy pierwotnej charakteryzującej się złożonym i często zmiennym składem (próbka oryginalna) do matrycy wtórnej z równoczesnym usunięciem substancji przeszkadzających (izolacja)i zwiększeniem stężenia analitów do poziomu powyżej granicy oznaczalności stosowanego przyrządu...
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Determination of Volatile Organic Compounds in indoor air in the Gdansk area using permeation passive samplers.
PublikacjaDozymetria pasywna, znana od wielu lat, jest użytecznym narzędziem w monitoringu poziomu zanieczyszczeń. Do określenia jakości powietrza wewnętrznego w 22 pomieszczeniach mieszkalnych, zlakoalizowanych na terenie Gdańska, wykorzystano dozymetry pasywne typu permeacyjnego na etapie pobierania próbek analitów. Uzyskane wyniki porównano z wynikami uzyskanymi przy wykorzystaniu matedy dynamicznej. Podjęto również próbę identyfikacji...
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Flow cytometric approach to evaluate the impact of hydro-technical concrete compounds’ release to the freshwater microbiome
PublikacjaThe aim of this research was to test the potential of applying a flow cytometric procedure to evaluate the impact of concrete compounds’ release to the freshwater microbiome. Cells from the collected samples were stained with a fluorogenic redox indicator dye that measures the redox potential of microbial cells. This novel approach was combined with the assessment of microorganisms’ penetration into the internal structures of concrete...
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High-density polyethylene/EPDM rubber blend composites of boron compounds for neutron shielding application
PublikacjaNovel materials with neutron shielding property were fabricated by incorporating boron compounds into highdensity polyethylene (HDPE)/Ethylene propylene diene monomer rubber (EPDM) blends. A detailed investigation on the morphological, thermal, mechanical, and neutron attenuation properties of suitable proportion of HDPE/EPDM blend with boric acid (BA), boron carbide (BC), and nano boron carbide (NBC) were performed. Morphology...
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Muramyl dipeptide-based analogs as potential anticancer compounds: Strategies to improve selectivity, biocompatibility, and efficiency
PublikacjaAccording to the WHO, cancer is the second leading cause of death in the world. This is an important global problem and a major challenge for researchers who have been trying to find an effective anticancer therapy. A large number of newly discovered compounds do not exert selective cytotoxic activity against tumorigenic cells and have too many side effects. Therefore, research on muramyl dipeptide (MDP) analogs has attracted interest...