Wyszukiwarka
Filtry
wszystkich: 1414
wyświetlamy 1000 najlepszych wyników Pomoc
Wyniki wyszukiwania dla: chemical analysis
-
Structural, physico-chemical and antioxidant characteristics of 2,2′-bipyridyl(iminodiacetato)oxidovanadium(IV) dihydrate
Publikacja -
Offal Chemical Composition from Veal, Beef, and Lamb Maintained in Organic Production Systems
Publikacja -
Estimation of the environmental risk posed by landfills using chemical, microbiological and ecotoxicological testing of leachates
Publikacja -
Soil chemical properties affect the reaction of forest soil bacteria to drought and rewetting stress
Publikacja -
Matcha Green Tea: Chemical Composition, Phenolic Acids, Caffeine and Fatty Acid Profile
Publikacja -
PHYSICO-CHEMICAL CHARACTERISTICS OF SELECTED HONEYS OF THE WEST POMERANIAN PROVINCE AND THE VALUE OF THEIR PRO-HEALTH
Publikacja -
Characteristics of microstructural phenomena occurring on the surface of protective gloves by the action of mechanical and chemical factors
Publikacja -
Chemical Characteristics and Sensory Evaluation of Raw and Roasted Buckwheat Groats Fermented by Rhizopus Oligosporus
Publikacja -
Physico-chemical properties of three-component mixtures based on chitosan, hyaluronic acid and collagen
Publikacja -
Changes in Chemical Composition and Accumulation of Cryoprotectants as the Adaptation of Anholocyclic Aphid Cinara tujafilina to Overwintering
Publikacja -
Ga complexes of 8-hydroxyquinoline-2-carboxylic acid: Chemical speciation and biological activity
Publikacja -
Comparison of the Chemical Composition and Antimicrobial Activity of <i>Thymus serpyllum</i> Essential Oils
Publikacja -
Quality of groundwater contaminated by leachates from seven Polish landfills - chemical and ecotoxicological classifications
PublikacjaArtykuł prezentuje rezultaty badań toksyczności ostrej i chronicznej próbek wód podziemnych pobranych spod składowisk odpadów komunalnych. Uzyskane wyniki porównano z wynikami badań parametrów fizykochemicznych. Jednocześnie dokonano klasyfikacji jakości badanych próbek w oparciu o zalecenia Komisji Helsińskiej, system oparty na wyznaczaniu parametru pT i kryteria ustanowione przez Persoone'a i współpracowników.
-
Chemical modification of natural immunomodulators tuftsin and muramyl dipeptide significantly influence their biological activity
Publikacja...
-
Effect of chemical composition on corrosion and wear behaviour of the composite Ni-Fe-Al2O3 coatings.
PublikacjaPrzedstawiono wyniki badań powłoki kompozytowej otrzymanej przez osadzanie katodowe galwaniczne w roztworze zawierającym sole niklu, żelaza oraz cząstki ceramiki Al2O3 o różnej wielkości i stężeniu. Wykazano, że charakterystyka ceramiki posiada wpływ na szybkość korozji i zużycia ściernego. W szczególności, zawartość ceramiki wpływa dodatnio na odporność na zużycie ścierne, ale nieco obniża odporność na zużycie korozyjne.
-
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...
-
Chemical, Physical, and Mechanical Properties of 95-Year-Old Concrete Built-In Arch Bridge
PublikacjaThis research aimed to determine the durability and strength of an old concrete built-in arch bridge based on selected mechanical, physical, and chemical properties of the concrete. The bridge was erected in 1925 and is located in Jagodnik (northern Poland). Cylindrical specimens were taken from the side ribs connected to the top plate using a concrete core borehole diamond drill machine. The properties of the old concrete were...
-
Effect of chemical structure on complexation efficiency of aromatic drugs with cyclodextrins: The example of dibenzazepine derivatives
PublikacjaIt is widely believed that the hydrophobic effect governs the binding of guest molecules to cyclodextrins (CDs). However, it is also known that high hydrophobicity of guest molecules does not always translate to the formation of stable inclusion complexes with CDs. Indeed, a plethora of other factors can play a role in the efficiency of guest–CD interactions, rendering structure-based prediction of the complexation efficiency with...
-
Environmental characteristics of a tundra river system in Svalbard. Part 2: Chemical stress factors
PublikacjaBacterial communities in the Arctic environment are subject to multiple stress factors, including contaminants, although typically their concentrations are small. The Arctic contamination research has focused on persistent organic pollutants (POPs) because they are bioaccumulative, resistant to degradation and toxic for all organisms. Pollutants have entered the Arctic predominantly by atmospheric and oceanic long-range transport,...
-
Storm petrels as indicators of pelagic seabird exposure to chemical elements in the Antarctic marine ecosystem
PublikacjaData on trace element bioavailability in the south-polar marine ecosystem is still scarce, compared to that relating to temperate zones. Seabirds can be used as indicators of ecosystem health and sentinels of environmental pollution, constituting a link between marine and terrestrial environments. Here, we analysed the concentration of 17 elements (with special emphasis on mercury, Hg) in feathers of adults and chicks of two pelagic...
-
Exploring synergistic effects in physical-chemical activation of Acorus calamus for water treatment solutions
PublikacjaThe research proposed a novel method of obtaining sorption material from readily available Acorus calamus bio- mass through a combination of physical and chemical activation processes. The material with the highest specific surface area (1652 m2 g−1) was obtained by physical activation with CO2, followed by chemical activation with KOH. Reversing the order of activation methods resulted in a lower specific surface area (1014 m2...
-
Investigation of the Efficiency of a Dual-Fuel Gas Turbine Combustion Chamber with a Plasma‒Chemical Element
PublikacjaThe study is devoted to the possibility of increasing the efficiency of the working process in dual-fuel combustion chambers of gas turbine engines for FPSO vessels. For the first time, it is proposed to use the advantages of plasma‒chemical intensification of the combustion of hydrocarbon fuels in the dual-fuel combustion chambers, which can simultaneously operate on gaseous and liquid fuels. A design scheme of a combustion chamber...
-
Determination of Failure Causes of a Steam Turbine Casing
PublikacjaThe paper presents results of research and failure analysis undertaken to determine failure causes of a steam turbine casing. After 130,000 hours of service the crack in a outer shell of the turbine casing was found. The inner shell of the casing was made of cast steel grade G21CrMoV5-7, and the outer shell of grade G20CrMo4-5. Following research were performed in order to determine causes of the casing failure: chemical analysis;...
-
Analisys of the failure of fixator used in bone surgery
PublikacjaThe Gamma nail (fixator) made of stainless steel, which has broken in the body, was subjected to examination. The fixator was removed from the patient femur. The fracture occurred in the area of the nail hole after two months' stay in the organism. The research included chemical composition, hardness of the Gamma nail material and the observation and analysis of the type of fracture. The research showed the fatigue failure of the...
-
The adiabatic potentials of low-lying electronic states of the NaRb molecule
PublikacjaAdiabatic potential energy curves and spectroscopic constants have been calculated for the NaRb molecule. The results of ten states of the symmetry Σ+, six states of the symmetry Π, and two states of the symmetry Δ are obtained by the nonrelativistic quantum chemical method used with pseudopotentials describing the interaction of valence electrons with atomic cores. Analysis is based on a comparison with the results of other theoretical...
-
The chemistry of river–lake systems in the context of permafrost occurrence (Mongolia, Valley of the Lakes). Part I. Analysis of ion and trace metal concentrations
PublikacjaThis study provides a description of water chemistry in river–lake systems located in central Mongolia, at the borderline of permafrost occurrence. The analysis involved water samples collected from two river–lake systems: Baydrag River–Böön Tsagaan Lake system, and Shargalyuut/Tuyn Rivers–Orog Lake system. In the water samples, ions and trace elements were detected and quantified. Additionally, the parameters of pH, electrical...
-
Self-refraction of acoustic pulses with shock fronts in some nonequilibrium media
PublikacjaThe nonlinear self-refraction of acoustic pulsed beams, which include shock fronts, is studied. The medium of sound propagation is a gas where thermodynamically nonequilibrium processes take place, such as exothermic chemical reaction or excitation of vibrational degrees of a molecule’s freedom. Comparative analysis of the features of sound propagation over gases where pure nonlinear attenuation of the shock wave occurs, and gases...
-
Cyanides in the environment—analysis—problems and challenges
PublikacjaCyanide toxicity and their environmental impact are well known. Nevertheless, they are still used in the mining, galvanic and chemical industries. As a result of industrial activities, cyanides are released in various forms to all elements of the environment. In a natural environment, cyanide exists as cyanogenic glycosides in plants seeds. Too much consumption can cause unpleasant side effects. However, environmental tobacco smoke...
-
Investigation on environmental chemistry changes in the Antarctic Special Management Area (ASMA 1): King George Island, South Shetlands Islands
PublikacjaThe doctoral dissertation included a review of the scientific literature that resulted in the selection of the research area, type of samples and chemical species that were marked. The published series of articles contains an in-depth description of the results of chemical analyses of surface water, sediment and snow samples from the Antarctic Specially Managed Area (ASMA 1) – King George Island. In addition, studies have been...
-
Direct injection liquid chromatography-mass spectrometry (DI-LC-MS) analysis for rapid lipidomic profiling of extracellular vesicles
PublikacjaExtracellular vesicles (EVs) are small, spherical particles produced by eukaryotic and prokaryotic cells, surrounded by a bilayer membrane and carrying various bioactive molecules, such as proteins, surface receptors, membrane and soluble proteins, lipids, and nucleic acids. EVs are of substantial interest because of their important roles in cell communication, epigenetic regulation and possible application in disease diagnosis...
-
State of the art in sample preparation for human breast milk metabolomics—merits and limitations
PublikacjaHuman breast milk (HBM) contains metabolites that are diverse in chemical structure and concentration. These metabolites range from high-abundance to low-abundance compounds and from polar to nonpolar. This complex nature of HBM makes HBM samples difficult to analyze, especially in global metabolomic studies for the determination and characterization of complete sets of metabolites. In this review, the state of the art in sample...
-
Failure analysis of the exhaust valve face in diesel marine engine
PublikacjaThe exhaust valve from marine diesel engine which was damaged after 2000 hours of service was investigated. In order to prolong the service time the valve face was cladded with cobalt base alloy using laser technique. After failure microstructural and chemical analyses reviled that cladding process was conducted improperly. The chemical composition of the clad layer was far from the designed one and what more completely inhomogeneous....
-
Kazimierz Darowicki prof. dr hab. inż.
OsobyStudia wyższe ukończyłem w czerwcu 1981 roku po zdaniu egzaminu dyplomowego i obronie pracy magisterskiej. Opiekunem pracy magisterskiej był dr hab. inż. Tadeusz Szauer. W roku 1991, 27 listopada uzyskałem stopień naukowy broniąc pracę doktorską zatytułowaną „Symulacyjna i korelacyjna analiza widm immitancyjnych inhibitowanej reakcji elektrodowej”. Promotorem pracy był prof. dr hab. inż. Józef Kubicki (Wydział Chemiczny...
-
Does the chemical modification of Nystatin A1 affect the drug's ability to overcome the multidrug resistance of fungi?
PublikacjaAlthough the contemporary medicine keeps moving forward, disseminated infections caused by fungal pathogens are an emerging challenge. The dramatic rise of fungal diseases, especially the most life-threatening systemic mycoses is associated with a permanently growing number of immunodeficient patients. Undoubted difficulties in the treatment of fungal infections are caused by lack of highly effective and selective antifungal drugs,...
-
Chemical composition, antioxidant and anticancer effects of the seeds and leaves and indigo (polygonum tinctorium Ait.) Plant
PublikacjaSeeds and leaves of indigo (Polygonum tinctorium Ait.) plant were investigated and compared with another medicinal plant named prolipid for their properties such as chemical composition, antioxidant, and anticancer effects by Fourier transform infrared, three-dimensional fluorescence spectroscopy, and electrospray ionization-MS in negative mode. It was found that polyphenols, flavonoids, and flavanols were significantly higher...
-
Application of chiral chromatography for enantiomeric separation of currently used pesticides from various chemical groups
PublikacjaChiral pesticides account for more than 25 % of currently used pesticides and this ratio is still increasing. According to the number of chiral centers in the structure, a pesticide may consist of two or multiple enantiomers or stereoisomers. Studies into the stereoselective behaviour of pesticides started in the early 1990s and most research efforts focused on understanding the environmental fate and effects of these pesticides....
-
Challenges in determination of pesticides from various chemical groups in fruits and vegetables applying QuEChERS method
PublikacjaPesticides are a large group of compounds with different physical and chemical properties, which place some of them among the most toxic, environmentally stable, and mobile substances. Nevertheless, their number, use, and application are continuously expanding. A consequence of their use is the possible presence of residues in treated food products. To protect consumers from exposure to unacceptable levels of pesticides Maximum...
-
Physico-chemical properties and possible photocatalytic applications of titanate nanotubes synthesized via hydrothermal method
Publikacja -
Influence of foliar fertilisation with calcium fertilisers on the firmness and chemical composition of two highbush blueberry cultivars
Publikacja -
Chemical and Enzymatic Changes of Different Soils during Their Acidification to Adapt Them to the Cultivation of Highbush Blueberry
Publikacja -
Experimental and Quantum Chemical Evaluation of 8-Hydroxyquinoline as a Corrosion Inhibitor for Copper in 0.1 M HCl
PublikacjaThe corrosion inhibition properties of 8-hydroxyquinoline (8-HQ) in 0.1 M HCl for copper have been investigated by using experimental (electrochemical impedance spectroscopy (EIS), dynamic electrochemical impedance spectroscopy (DEIS), and potentiodynamic polarization) and theoretical methods complemented by surface morphological examination with the aid of scanning electron microscopy (SEM) and electron dispersive X-ray spectroscopy...
-
Chemical structure, thermal and mechanical characterization of bio-based polyurethane composites filled with microcrystalline cellulose
PublikacjaOver the past several decades, the interest in replacing the synthetic components used in the production of polymers and composites with their natural counteparts has been growing. Biocomposites belong to the group of materials produced with the use of renewable raw materials. There has been a recent surge of interest in the industrial applications of composites containing natural fibres reinforced with biopolymers. Biopolymers...
-
Combined chemical-biological treatment of effluents from soil remediation processes by surfactants solutions flushing
PublikacjaŚcieki powstające podczas procesu remediacji gruntu zawierają surfaktanty o wysokim stężeniu oraz oleje w postaci zemulgowanej i zsolubilizowanej lub wolnej. Do oczyszczenia takich ścieków zastosowano chemiczne utlenianie, biologiczne oczyszczanie oraz zintegrowany proces chemiczno biologiczny. Efektywność procesu oceniono na podstawie redukcji ChZT oraz zmiany stężenia surfaktantu w oczyszczanych ściekach. Chemiczne utlenienie...
-
Modelling of First- and Second-order Chemical Reactions on ARUZ – Massively-parallel FPGA-based Machine
Publikacja -
Synergistic effects of low-/medium-vacuum carbonization on physico-chemical properties and stability characteristics of biochars
Publikacja -
Biological and Physico-Chemical Characteristics of Arginine-Rich Peptide Gemini Surfactants with Lysine and Cystine Spacers
Publikacja -
Retro analog concept: comparative study on physico-chemical and biological properties of selected antimicrobial peptides
Publikacja -
The impact of sediment, fresh and marine water on the concentration of chemical elements in water of the ice-covered lagoon
PublikacjaThe common use of chemical elements by man has been contributing to their extraction for centuries. As a consequence, they have been directly or indirectly introduced into the biogeochemical cycle. In the framework of many conventions, mining and processing of elements are currently subject to many restrictions. However, their large load that has already been deposited in the soil and bottom sediments can be remobilised and...
-
<title>Novel matrix for fiber optic chemical sensors made of particle track polymer</title>
Publikacja -
Chemical Composition, In Vitro and In Situ Antimicrobial and Antibiofilm Activities of Syzygium aromaticum (Clove) Essential Oil
Publikacja