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Wyniki wyszukiwania dla: enzymatic activity determination
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Simultaneous Determination of pKa and Lipophilicity by Gradient RP HPLC
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Methods of selenium supplementation. Bioavability and determination of selenium compounds
PublikacjaIn This paper the method of supplementation of selenium in the environment and analytical methods of determining selenium were described
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VOLTAMMETRIC DETERMINATION OF DEOXYRIBONUCLEIC ACID PRESENCE ON A CARBON ELECTRODE
PublikacjaThis paper presents a voltammetry as a useful method to analyse DNA from different species. This electrochemical method is well know and used in different analyses. The influence of an area of working electrode and the capacity component, is shown at equals and the measurement. In voltammetry DNA measurement the capacity component is very important and must be taken into consideration. All mathematical analyses were verify at laboratory.
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Determination of some off-flavors for vodka quality assessment
PublikacjaW pracy zostały przedstawione wyniki analizy wybranych związków karbonylowych w wódkach czystych z wykorzystaniem procedury HS-SPME/GC-ECD poprzedzonej derywatyzacją aldehydów za pomocą odczynnika PFBHA. Przeprowadzone badania wykazały, że obecność 2,3-pentanodionu i 2-butenalu skutkuje pogorszeniem jakości analizowanych wódek.
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Some analytical assays for the determination of bioactivity of exotic fruits
PublikacjaPrzedmiotem badań były próbki owoców egzotycznych (mango, durian, gruszka adwokacka) zebrane w 2008 roku w Tajlandii i w Izraelu (po etapie liofilizacji). W próbkach oznaczano zawartość:- białek, - tłuszczów,- węglowodanów,- flawonoidów,- tanin- polifenoli stosując zarówno zaawansowane techniki instrumentalne jak i proste testy spektrofotometryczne (FRAP, ABTS, DPPH, CUPRAC). Uzyskana wieloparametrowa baza danych pomiarowych została...
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Green aspects of techniques for the determination of pesticides in fruits and vegetables
PublikacjaApplied all over the world, pesticides are some of the most dangerous pollutants of the environment because of their stability, mobility, their ability to accumulate in the environment and their consequent long-term adverse effects on living organisms in general and human health in particular. Their presence in the environment is a particular danger. It is therefore crucial to monitor pesticide residues using all available analytical...
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Experimental determination of basic mechanical properties of elastomeric polymer
PublikacjaThere are a lot of different methods of repairing and reinforcing damaged structures, but when it comes to historical buildings and other cultural heritage objects, it is as much about mechanical safety as the aesthetical aspects. Recently, a new and innovative method of repairing damaged structures by filling the cracks with a specially prepared polymer mass has been proposed. This new and innovative technique, known as the Flexible...
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Determination of impurities in pharmaceutical products using LC-MS
PublikacjaPharmaceutical products can be contaminated by residues of solvents, reagents (used for the synthesis) or degradation products. Impurities in drug may pose a risk to human health and life, therefore analysis and identification of impurities in pharmaceutical products is veryimportant and inevitable.High performance liquid chromatography coupled with mass spectrometry (MS) is very useful technique for identification impurities in...
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Determination of pesticide residues in food matrices using the QuEChERSmethodology
PublikacjaOznaczanie pozostałości pestycydów w próbkach żywności jest ogromnym wyzwaniem głównie z powodu dużych ilości substancji przeszkadzających, które podlegają ekstrakcji razem z analitami i najczęściej wywierają negatywny wpływ na tok analizy. Z drugiej strony, zapewnienie "bezpieczeństwa żywności" wymaga monitorowania w niej pozostałości pestycydów. W artykule przedstawiono nowe podejście do oznaczania pozostałości pestycydów w próbkach...
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Determination of biogenic amines in beers by LC-MS/MS
PublikacjaAnalysis of biogenic amines in beers was carried out by HPLC-MS/MS after their derivatization with p-toluenesulfonyl chloride (tosyl chloride). The developed method has been applied for analysis of eighteen biogenic amines in twelve samples of different kind of beers (Lager, Strong Lager, Schwarzbier, Weizenbier, Pils, nonalcoholic Pils, Stout). The method is sensitive and the results precise for majority of the analytes.
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Determination of Mathematical Model Parameters of a Medium Frequency Transformer
PublikacjaThe paper presents the results of experimental studies of the medium frequency transformer. The object of the research was a prototype of a single-phase transformer with a core made of ferrite I-core elements and windings made of Litz conductors. The research was carried out to determine the parameters of the transformer's mathematical model. The scope of the tests included determining the magnetic hysteresis loop and measuring...
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Determination of the Vehicles Speed Using Acoustic Vector Sensor
PublikacjaThe method for determining the speed of vehicles using acoustic vector sensor and sound intensity measurement technique was presented in the paper. First, the theoretical basis of the proposed method was explained. Next, the details of the developed algorithm of sound intensity processing both in time domain and in frequency domain were described. Optimization process of the method was also presented. Finally, the proposed measurement...
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Characteristic of Morpholinium Ionic Liquids as Gas Chromatography Stationary Phases with McReynolds Constants and Activity Coefficients at Infinite Dilution
PublikacjaIn this work, four ionic liquids based on N-alkyl-N-methylmorpholinium cation ([Mor1,R] where R= 2, 4, 8, 10) and bis(trifluoromethanesulfonyl)imide anion [TFSI] were synthesized. Using gas-liquid chromatography a number of parameters describing the sorption properties of the investigated ionic liquids were determined. The values of Kovats indices, McReynolds constants, and activity coefficients at infinite dilution were the basis...
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Determination of Odor Intensity of Binary Gas Mixtures Using Perceptual Models and an Electronic Nose Combined with Fuzzy Logic
PublikacjaMeasurement and monitoring of air quality in terms of odor nuisance is an important problem. From a practical point of view, it would be most valuable to directly link the odor intensity with the results of analytical air monitoring. Such a solution is offered by electronic noses, which thanks to the possibility of holistic analysis of the gas sample, allow estimation of the odor intensity of the gas mixture. The biggest problem...
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Structural features responsible for control of the eukaryotic GlcN-6-P synthase activity
PublikacjaGlucosamine-6-phosphate (GlcN-6-P) synthase is responsible for catalysis of the first and practically irreversible step in hexosamine metabolism. As UDP-GlcNAc, the final product of the hexosamine path, constitutes one of the essential substrates for assembly of bacterial and fungal cell walls, the enzyme is an interesting target for antimicrobial therapy.The structure of E. coli enzyme, known since 2001, forms a dimer of two identical...
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Antiproliferative activity of anthraquinones determined by clonogenic assay
Dane BadawczeThe data contains the colony formation analysis in A549, H460 and H226 cells after exposure to TXT2 and TXT4. DMSO was used as a negative control.
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Determination of selected chemical parameters in surface water samples collected from the Revelva catchment (Hornsund fjord, Svalbard)
PublikacjaSurface water samples (river and lake) were collected from the Revelva catchment every summer from 2010 to 2013. This study concerns importance of the use of some analytical techniques for pollutants and parameters deter- mination in Arctic environmental samples based on the example of total organic carbon, phenols, and formaldehyde determination and measurement of pH and electrical conductivity parameters. Significant...
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Revisiting The Determination Of Cutting Power While Sawing Of Wood With Circular Saw Blades By Means Of Fracture Mechanics
PublikacjaIn the classical approach, energetic effects (cutting forces and cutting power) of wood sawing process are generally calculated on the basis of the specific cutting resistance, which is in the case of wood cutting the function of more or less important factors. On the other hand, cutting forces (power) could be considered from a point of view of modern fracture mechanics. Cutting forces may be employed to determine not only toughness...
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Direct solid phase microextraction combined with gas chromatography – Mass spectrometry for the determination of biogenic amines in wine
PublikacjaA direct method based on immersion solid phase microextraction (DI-SPME) gas chromatography mass-spectrometry (GC-MS) was optimized and validated for the determination of 16 biogenic amines in Polish wines. In the analysis two internal standards were used: 1,7-diaminoheptane and bis-3-aminopropylamine. The method allows for simultaneous extraction and derivatization, providing a simple and fast mode of extraction and enrichment....
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A novel cold-active β-D-galactosidase with transglycosylation activity from the Antarctic Arthrobacter sp. 32cB - gene cloning, purification and characterization
PublikacjaA gene encoding a novel β-D-galactosidase from the psychrotolerant Antarctic bacterium Arthrobacter sp. 32cB was isolated, cloned and expressed in Escherichia coli. The active form of recombinant β-D-galactosidase consists of two subunits with a combined molecular weight of approximately 257 kDa. The enzyme's maximum activity towards o-nitrophenyl-β-D-galactopyranoside was determined as occurring at 28 °C and pH 8.0. However, it...
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Selected symmetrically substituted carbazoles: Investigation of anticancer activity and mechanisms of action at the cellular and molecular levels
PublikacjaDNA topoisomerases play a critical role as essential enzymes in controlling alterations in the topology of DNA. They achieve this by orchestrating the coordinated process of breaking and rejoining DNA strands, which is crucial for maintaining the proper structure of DNA during regular cellular development. The search for and development of new potential anticancer drugs is a challenging yet immensely important area of research...
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A Cu/Zn heterometallic complex with solvent-binding cavity, catalytic activity for the oxidation of 1-phenylethanol and unusual magnetic properties
PublikacjaMononuclear and polymeric complexes of zinc(II) and copper(II) have been synthesized using two isomers of the hemi-salen ligand with a different mutual orientation of donor atoms. The heterometallic Cu/Zn metallocycle features a catalytic niche filled with the molecule of water and molecules of methanol. This unusual compound exhibits both pronounced catalytic activity in the reaction of oxidation of a secondary alcohol to ketone...
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Determination of benzodiazepines and Z-hypnotic drugs in whole blood samples by GC–MS/MS: Method development, validation and application
PublikacjaBenzodiazepines (BZDs) and Z-drugs are widely used as anxiolytics, sedative hypnotics, anticonvulsants and muscle relaxants. “Designer benzodiazepines” (DBZDs) are a new psychoactive substance class consisting of benzodiazepine derivatives that are not allowed for medical use and are known for being used recreationally. From a toxicologist standpoint, the huge number of such substances implicate a necessity for developing fast...
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A Method for Determination and Compensation of a Cant Influence in a Track Centerline Identification Using GNSS Methods and Inertial Measurement
PublikacjaAt present, the problem of rail routes reconstruction in a global reference system is increasingly important. This issue is called Absolute Track Geometry, and its essence is the determination of the axis of railway tracks in the form of Cartesian coordinates of a global or local coordinate system. To obtain such a representation of the track centerline, the measurement methods are developed in many countries mostly by the using...
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Trace Metal Contamination of Bottom Sediments: A Review of Assessment Measures and Geochemical Background Determination Methods
PublikacjaThis paper provides an overview of different methods of assessing the trace metal (TM) contamination status of sediments affected by anthropogenic interference. The geochemical background determination methods are also described. A total of 25 papers covering rivers, lakes, and retention tanks sediments in areas subjected to anthropogenic pressure from the last three years (2019, 2020, and 2021) were analysed to support our examination...
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Investigation of the Antifungal Activity and Mode of Action of Thymus vulgaris, Citrus limonum, Pelargonium graveolens, Cinnamomum cassia, Ocimum basilicum, and Eugenia caryophyllus Essential Oils
PublikacjaThe antimicrobial activity of plant oils and extracts has been recognized for many years. In this study the activity of Thymus vulgaris, Citrus limonum, Pelargonium graveolens, Cinnamomum cassia, Ocimumbasilicum, and Eugenia caryophyllus essential oils (EOs) distributed by Pollena Aroma (Nowy Dwór Mazowiecki, Poland) was investigated against a group of 183 clinical isolates of C. albicans and 76 isolates of C. glabrata. All of...
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The impact of mass-media campaigns on physical activity: a review of reviews through a policy lens
PublikacjaBackground This review of reviews aimed to: (1) summarize the evidence from published reviews on the effectiveness of mass-media campaigns to promote physical activity (PA) or PA-related determinants (intermediate psychological and proximal outcomes) and (2) to identify policy-relevant recommendations related to successful PA campaigns. Methods An extensive literature search was performed on 1 March 2021. Reviews that evaluated...
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Sustainable Urban Mobility Plans: implementation process and indicators to evaluate effects on physical activity
PublikacjaBackground: Active mobility and public transport increase physical activity (PA) levels. With varying intensity and effectiveness, European cities implement Sustainable Urban Mobility Plans (SUMPs) to spur transport-related PA. Therefore, we aim to examine drivers and barriers to SUMP implementation and assess its influence on PA across European cities. Methods: We screened policy reports to gain insights into SUMP implementation...
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Novel 1,2,3-Triazole Derivatives as Mimics of Steroidal System—Synthesis, Crystal Structures Determination, Hirshfeld Surfaces Analysis and Molecular Docking
PublikacjaHerein, we present the synthesis and crystal structures determination of five 4-(1-phenyl-1H-1,2,3-triazol-4-yl)phenol derivatives containing halogen atoms, 6a–e, which may be used as an excellent mimic of steroids in the drug development process. Good quality crystals obtained for all of the synthesized compounds allowed the analysis of their molecular structures. Subsequently, the determined crystal structures were used to calculate...
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Photosensitive and pH-dependent activity of pyrazine-functionalized carbazole derivative as promising antifungal and imaging agent
PublikacjaCarbazole skeleton plays a significant role as a structural scaffold of many pharmacologically active compounds. Pyrazine-functionalized carbazole derivative was constructed by coupling 2-amino-5-bromo-3-methylaminepyrazine (ABMAP) into 3 and 6 positions of the carbazole ring. Multi-experimental methods were used, e.g., potentiometric, spectroscopic (ATR, UV, XRD powder,1H and13C NMR), electrochemical (cyclic voltammetry), and...
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Novel fast analytical method for indirect determination of MCPD fatty acid esters in edible oils and fats based on simultaneous extraction and derivatization
PublikacjaA novel method for indirect determination of MCPD esters levels in lipid samples has been developed. The method is based on combination of extraction and derivatisation in the same sample preparation step. It is achieved by the application of diethyl ether as extraction solvent for isolation of released from esterified forms analytes from water phase and dilution solvent for solid PBA – derivatisation agent. It is a noteworthy...
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Discrepancies in determination of biogenic amines in beer samples by reversed phase and hydrophilic interaction liquid chromatography coupled with tandem mass spectrometry
PublikacjaBiogenic amines (BAs) are nitrogenous organic bases occurring mainly in fermented food and beverages as a result of free amino acids bacterial decarboxylation. The reversed phase liquid chromatography (RPLC) and hydrophilic interaction liquid chromatography (HILIC) based methods were compared in terms of usefulness for determination of BAs in beer samples. Analysis of BAs with the use of RPLC method were carried out after their...
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Lanthanide co-doped TiO2: the effect of metal type and amount on surface properties and photocatalytic activity
PublikacjaPreparation of new rare earth metal-containing TiO2 nanocomposites (Nd3+/Er3+, Nd3+/Eu3+, Eu3+/Ho3+-TiO2) using sol–gel route and their photoactivity under visible and ultraviolet light is reported. The obtained photocatalysts were subsequently characterized by Brunauer–Emmett–Teller (BET) method, UV–Vis diffuse-reflectance spectroscopy (DRS), luminescence spectroscopy, X-ray photoelectron spectroscopy (XPS) and X-ray powder diffraction...
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Application of ion chromatography with pulsed amperometric detection for the determination of trace cyanide in biological samples, including breast milk
PublikacjaCyanide (CN) is the biomarker of exposure to the components of tobacco smoke, although its presence in biological samples is also due to the consumption of products containing cyanogenic glycosides. In this work, we determine the concentration of the free cyanide in urine, saliva and breast milk matrices, using ion chromatography with pulsed amperometric detection (IC-PAD). IC-PAD is an emerging method, with only few documented...
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Mono- and bimetallic nanoparticles decorated KTaO 3 photocatalysts with improved Vis and UV–Vis light activity
PublikacjaNew mono- and bimetallic nanoparticle-decorated perovskite-type KTaO3 photocatalysts were successfully synthesized by hydrothermal reaction followed by photodeposition of MNPs/BNPs. The effect of noble metal type, amount of metal precursor as well as photoreduction method on the physicochemical and photocatalytic properties of MNPs- and BNPs-KTaO3 have been investigated. Photocatalytic activity under Vis light irradiation was estimated...
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Modern approach for determination of lactulose, mannitol and sucrose in human urine using HPLC-MS/MS for the studies of intestinal and upper digestive tract permeability
PublikacjaA new analytical procedure was described for the simultaneous determination of lactulose, mannitol and sucrose in urine, in which HILIC chromatography and tandem mass spectrometry detection are used. Sugars are orally administered for the estimation of intestinal permeability in children digestive tract. Samples were purified by dispersive solid phase extraction (d-SPE) using Amberlite MB150 resin. Raffinose was selected as an...
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Determination of Vehicles Load Equivalency Factors for Polish Catalogue of Typical Flexible and Semi-rigid Pavement Structures
PublikacjaThe new Polish Catalog of Typical Flexible and Semi-rigid Pavement Structures was introduced to use in practice in 2014. Much of works were focused on actualization of vehicles load equivalency factors. For this purpose data delivered from weigh-inmotion were analyzed. Four methods of determination of load equivalency factors for pavement structure design were compared. The analysis showed that fourth power equation, AASHTO 1993...
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Application of dispersive liquid - liquid microextraction for determination of pesticides from various chemical groups in water samples
PublikacjaPesticides are a global risk because they move with the wind, rain and sea currents from other regions, which makes getting to places which were never used before. Their presence was detected in all types of water circulating in the ecosystem, which is an easy source of exposure to life and health of all living organisms. Currently, it is considered one of the most dangerous and toxic pollutants, which fate and function is still...
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Determination of the Theoretical and Actual Working Volume of a Hydraulic Motor—Part II (The Method Based on the Characteristics of Effective Absorbency of the Motor)
Publikacja: In this article, the second method of determination of the theoretical and actual working volume of a hydraulic motor is described. The proposed new method is based on the characteristics of effective absorbency of the motor. The effective absorbency has been defined as the ratio of flow rate in a motor to the rotational speed of the motor’s shaft. It has been shown that the effective absorbency is a nonlinear function of the...
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The impact of cooking method on the phenolic composition, total antioxidant activity and starch digestibility of rice (Oryza sativa L.)
PublikacjaThis study investigated changes in the phenolic composition, total antioxidant activity (TAA) and starch digestibility in white and brown rice due to three different cooking procedures, and subsequent reheating of cooked rice after storage. Among the analyzed samples, brown rice showed the highest TAA and phenolic content (622.5 mg kg-1 DW). All cooking methods resulted in significant decrease of phenolic content and TAA of rice...
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Molecular basis and potential activity of HIV-1 reverse transcriptase toward trimethylamine-based compounds
PublikacjaReverse transcriptase (RT) inhibitors are currently used to treat human immunodeficiency virus (HIV)-1 infections. In this work, novel triethylamine derivatives were designed and studied by rigid and flexible docking and molecular dynamics (MD) approaches. An apo form of HIV-1 RT was also studied by MD simulation to analyze comparative response of protein in ligand-bound and ligand-unbound forms. Among newly designed HIV-1 RT inhibitors,...
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Perovskite-type KTaO3–reduced graphene oxide hybrid with improved visible light photocatalytic activity
PublikacjaNovel rGO–KTaO3 composites with various graphene content were successfully synthesized using a facile solvothermal method which allowed both the reduction of graphene oxide and loading of KTaO3 nanocubes on the graphene sheets. The as-prepared photocatalysts were characterized by X-ray diffraction (XRD), transmission electron microscopy (TEM), scanning electron microscopy (SEM) with energy dispersive X-ray analysis (EDX), Fourier...
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Antimicrobal and ostheointegration activity of bone cement contains nanometals
PublikacjaPurpose: One of the major problems in bone surgery are infections – especially thoseoccurring in the course of the operating on the patients with lowered immunity system,because they carry the danger of complications. In the Mechanical Department of TechnicalUniversity of Gdansk, there has been carried the research with the use of bone cement andmetal nanoparticles.Design/methodology/approach: The bone cement was used without supplement...
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Biological activity of conjugates of muramyl dipeptides with batracylin derivatives
PublikacjaW artykule opisano aktywność biologiczną koniugatów muramylo-dipeptydów z batracyliną lub pochodnymi batracyliny. Badania przeprowadzone w Akademii Medycznej w Gdańsku miały na celu oznaczenie immunomodulacyjnych właściwości tych koniugatów wobec subpopulacji leukocytów krwi obwodowej hodowanych w obecności komórek nowotworowych (K562, WEHI164, Ab melanoma). Leukocyty izolowane były z krwi obwodowej uzyskanej od zdrowych ochotników....
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Physical Activity and Cognitive Functioning of Children: A Systematic Review
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Synthetic analogues of cyanobacterial alkaloid cylindrospermopsin and their toxicological activity
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Selected biologic markers of inflammation and activity of Crohn’s disease
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Quality of Life with Respect to Physical Activity Level in the Unemployed
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Sociodemographic Associations of Physical Activity in People of Working Age
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Preparation and photocatalytic activity of B-doped titanium dioxide
PublikacjaOtrzymano TiO2 domieszkowany borem, aktywny w reakcjach fotodegradacji pod wpływem światła widzialnego (λ>400 nm). Fotokatalizatory otrzymano poprzez hydrolizę tytanianu(IV) izopropylu w obecności związków boru lub poprzez ucieranie ST-01 z prekursorami B i następnie kalcynację w temperaturze 450stC. Jako źródło boru zastosowano kwas borowy (0,5 i 10%wag.) lub trietylo ester kwasu borowego (0,5; 1; 5 i 10%wag.). Najwyższą aktywność...