Search
Filters
total: 2139
filtered: 1569
displaying 1000 best results Help
Search results for: determination
-
Review of the determination of modern used pesticides in water samples
PublicationThe increasingly widespread application of pesticides causes that larger amounts of them are entering the environment. Their presence in sources of drinking water, essential to life, is a particular danger. For these reasons it is important to monitor and analyse pesticide residues in the environment. The analysis of environmental samples for the presence of pesticides is very difficult. Firstly, the processes involved in sample...
-
Determination of Selected Metals in Fruit Wines by Spectroscopic Techniques
PublicationThe determination of metals in different types of food and beverages samples has drawn significant attention due to several reasons with the most important one being the nutritional and toxic effects of these elements or their compounds. The knowledge of certain elements content in wines/fruit wines is of special interest due to their toxicity in case of excessive intake and also the effect they seem to have on the organoleptic...
-
Influence of preprocessing techniques on pulse pressure velocity determination
PublicationPulse Wave Velocity (PWV) is measured and utilized in many clinical applications. Recently, a wide research has been led to develop a cuff-less and continuous blood pressure method basing on PWV. However, in this application a decision on choosing an appropriate fiducial point of pulse wave (PW) waveform is necessary and substantial. It would allow to measure time parameters necessary to determine PWV. An influence of sampling...
-
Experimental tests for the determination of mechanical properties of PVC foil
PublicationThe paper presents an application of the PVC film in civil engineering. Mechanical behaviour of the PVC film applied for suspended ceilings, in the form of a stretch ceiling is investigated under uniaxial and biaxial tensile tests. The study is focused on the determination of mechanical properties from experimental data (uniaxial and biaxial tensile tests). The uniaxial cyclic tests are performed in order to observe a variation...
-
The use of low-coherence interferometer for sugar content determination
PublicationIn this article, the implementation of low-coherence interferometer with signal processing in time domain for sugar content determination in aqueous solution is presented. The elaborated measurement set-up was tested with the use of synthesized source made of two low-coherence sources. The use of two sources with dedicated parameters enabled to obtain a proper metrological parameters of the measurement system. The elaborated low-coherence...
-
Recent trends in determination of neurotoxins in aquatic environmental samples
PublicationAnatoxins, saxitoxins, ciguatoxins, beta-N-methylamino-l-alanine and its isomers are groups of neurotoxins which have a highly specific effect on the nervous system of animals, including humans, by interfering with the transmission of nerve impulses. In order to assess the human exposure to these neurotoxins, selective, interlaboratory-validated analytical methods are being developed to facilitate obtaining reliable results on...
-
Detection, identification and determination of resveratrol in wine. Problems and challenges
PublicationResveratrol is a compound synthesized by plants in response to unfavorable conditions of growth like mechanical injury, siege of bacteria or fungi and UV exposure. It is concentrated mostly in grapes skin and further more in the products made from grapes especially red wines. Each wine is characterized by different amount of given stilbene since its occurrence is affected by many factors like: types of grapes, environment (climate,...
-
Determination of the theoretical and actual working volume of a hydraulic motor
PublicationA new methodology of determination of the theoretical and actual working volume of a hydraulic motor based on the characteristics of the delivered flow rate into hydraulic motor vs. the rotational speed at a constant pressure drop in the working chambers is described in this paper. A new method of describing the delivered flow rate into a motor per one shaft revolution as a nonlinear function of the pressure drop in the motor working...
-
The current threshold value in potentiodynamic determination of the breakdown potential
Publication -
Determination of electrode impedance by means of exponential chirp signal
Publication -
Methods of Selenium Supplementation: Bioavailability and Determination of Selenium Compounds
Publication -
Determination of pKa by pH Gradient Reversed-Phase HPLC
Publication -
Simultaneous Determination of pKa and Lipophilicity by Gradient RP HPLC
Publication -
Chemometric methods for determination of mechanisms of action of anticancer compounds
PublicationW 1990 amerykański Narodowy Instytut Raka (NCI) wprowadził szeroki test przesiewowy in vitro mający na celu poszukiwanie nowych związków przeciwnowotworowych. Test został wdrożony po przebadaniu 171 standardowych związków przeciwnowotworowych. Przedmiotem niniejszej pracy jest próba stworzenia reguł klasyfikacji związków standardowych ze względu na ich mechanizm działania przeciwnowotworowego na podstawie wyników z testu NCI. Potwierdzono...
-
Preparation of soil and sediment samples for the determination of organometallic compounds
PublicationZwiązki metaloorganiczne są szeroko stosowane niemal we wszystkich gałęziach przemysłu. W wyniku ich emisji, zarówno ze źródeł naturalnych jak i antropogenicznych, nastąpiło ich rozprzestrzenienie w środowisku, w którym ulegają szeregowi przemian chemicznych. Niektóre z tych związków charakteryzują się wysoką toksycznością. W oparciu o literaturę naukową dotyczącą procedur oznaczania wybranych związków metaloorganicznych rtęci,...
-
Some analytical assays for the determination of bioactivity of exotic fruits
PublicationPrzedmiotem 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...
-
Determination of pesticide residues in food matrices using the QuEChERSmethodology
PublicationOznaczanie 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...
-
Determination of some off-flavors for vodka quality assessment
PublicationW 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.
-
Use of the AHP Method for Preference Determination in Yacht Design
PublicationA sailing yacht is a human-centred product, the design of which revolves primarily around the wants and desires of the future owner. In most cases, these preferences are not measurable, such as a personal aesthetic feeling, or a need for comfort, speed, safety etc. The aims of this paper are to demonstrate that these preferences can be classified and represented numerically, and to show that they are correlated with the type...
-
MTS pilot tone tracking for "wow" distortion determination
PublicationArtykuł przedstawia nowy algorytm do wyznaczania charakterystyki kołysania dźwięku na podstawie śledzenia zmian tonu pilota MTS. Śledzenie zmian częstotliwości nośnej tonu MTS pozwala określić zmienną w czasie głębokość pasożytniczych modulacji częstotliwości będących konsekwencją kołysania. Na tej podstawie tworzona jest charakterystyka zniekształcenia. Proponowany algorytm bazuje na zaproponowanej wcześniej metodzie śledzenie...
-
Determination of aminoglycoside antibiotics: Current status and future trends
Publication -
The analysis of the determination of points positions using photogrammetric methods
PublicationThis article was created as a result of research conducted within the master thesis. The purpose of the research was to analyze the accuracy of determining the actual position of the photographed points according to the calculated parameters. The accuracy of photos alignment was determined as parameters, which determine their external and internal orientation. In order to determine the location of the determined points, it was...
-
Determination of Antioxidant Activity of Vitamin C by Voltammetric Methods
PublicationVoltammetric methods—cyclic (CV) and differential pulse voltammetry (DPV) are considered the most appropriate way to evaluate antioxidant activity of redox active compounds. They provide information about both mechanism and kinetics of electrochemical oxidation of antioxidants as well as their physical and chemical properties such as the redox potential or the number of electrons transferred. These methods are helpful for understanding...
-
Determination of Mathematical Model Parameters of a Medium Frequency Transformer
PublicationThe 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...
-
Green aspects of techniques for the determination of pesticides in fruits and vegetables
PublicationApplied 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...
-
Experimental determination of basic mechanical properties of elastomeric polymer
PublicationThere 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...
-
Determination of impurities in pharmaceutical products using LC-MS
PublicationPharmaceutical 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...
-
Determination of biogenic amines in beers by LC-MS/MS
PublicationAnalysis 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.
-
Determination of the Vehicles Speed Using Acoustic Vector Sensor
PublicationThe 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...
-
VOLTAMMETRIC DETERMINATION OF DEOXYRIBONUCLEIC ACID PRESENCE ON A CARBON ELECTRODE
PublicationThis 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.
-
Determination of electrode impedance by means of exponential chirp signal.
PublicationPrzedstawiona została nowa metoda pomiaru impedancji elektrodowej. Jako pobudzenie zastosowany został niestacjonarny sygnał napięciowy, którego częstotliwość jest ekspotencjalną funkcją czasu. Zastosowanie zmodyfikowanej któtko-czasowej transformaty Fouriera (STFT) w analizie napięciowego pobudzenia i odpowiedzi prądowej pozwala na otrzymanie widma impedancyjnego.
-
Impedance measurements of skin layered structure for burns determination.
PublicationW pracy analizowany jest dwuwarstwowy model skóry. Pokazano, że za pomocą wielokrotnych pomiarów immitancyjnych jest możliwe wyznaczenia zarówno parametrów elektrycznych oparzonej skóry jak i geometrycznych. Przedstawiono algorytm estymacji i procedurę pomiarową wyżej wymienionych parametrów.
-
Rational determination of dynamic characteristics of fluid-flow Reactors
PublicationPodstawowa charakterystykę reaktorów stanowi krzywa rozkładu czasu zatrzymania. Jej dokładne wyznaczenie jest trudne i kosztowne. W pracy zaproponowano wykorzystanie metody aproksymacyjnej, polegającej na zastąpieniu rzeczywistej funkcji przez jej przebieg uproszczony. Zaproponowano aproksymację rozkładem trójkątnym. Na konkretnym przykładzie pokazano, że metoda ta daje lepsze wyniki niż powszechnie stosowany model przepływu tłokowego.
-
Usability of calculation methods for saw blade stiffness determination.
PublicationW pracy przedstawiono metodykę wyznaczania sztywności poprzecznej pił określanej na linii zębów. Prezentowana metodyka może być wykorzystywana zarówno do pił trakowych jak i taśmowych. Podano zalecenia wyboru odpowiedniej metody obliczeniowej w zależności od szerokości brzeszczotu piły.
-
Determination of binder-aggregate adhesion by contact angle measurement
PublicationThe key factor in asphalt pavement durability, especially in the presence of water, is adhesion of the bituminous binder to mineral aggregates. There are currently no standard laboratory test procedures that can quickly and accurately measure the strength of the interaction (bond) between the binder and aggregate. In this regard, to evaluate the adhesion force measurements based on the contact angle between the binder and the aggregate...
-
Methods of selenium supplementation. Bioavability and determination of selenium compounds
PublicationIn This paper the method of supplementation of selenium in the environment and analytical methods of determining selenium were described
-
Determination of safety indicators of the freight wagons by mobile systems
PublicationThe organization of the movement of freight trains in Ukraine is an important factor in integrating the country’s railway transport into the European system. A situation that requires a significant renewal of the freight wagon park with modern wagons to meet the freight transportation requirements has arisen. Also, a significant drawback of railway transport in Ukraine is the limitation of the speed of trains, which include freight...
-
Use of the AHP Method for Preference Determination in Yacht Design
PublicationA sailing yacht is a human-centred product, the design of which revolves primarily around the wants and desires of the future owner. In most cases, these preferences are not measurable, such as a personal aesthetic feeling, or a need for comfort, speed, safety etc. The aims of this paper are to demonstrate that these preferences can be classified and represented numerically, and to show that they are correlated with the type of...
-
Determination of Liquid Detergent Pods as a Potential Microplastic Source
PublicationWashing pods became a popular way to add detergent to washing machines. Despite the claims about the degradability of the pod film, the sludge in pipes can be observed after the usage of such pods. This study focused on a quantitative and qualitative analysis of washing pod films as a source of microplastic.
-
Determination of toluene formed during fermentation of sewage sludge
PublicationW pracy przedstawiono wyniki oznaczeń toluenu w próbkach osadów ściekowych przy wykorzystaniu techniki wypłukiwania i jednoczesnego wychwytywania analitów (PT). Badania procesu feremntacji osadów ściekowych doprowadziły do stwierdzenia, że w trakcie tego procesu powstaje toluen. Stwierdzono wzrost stężenia toluenu od poziomu 3 mg/l do ponad 24 mg/l dla próbek osadów ściekowych z Oczyszczalni Gdańsk -Wschód oraz od poziomu 0,6 mg/l...
-
Current trends in analytical strategies for the determination of polybrominated diphenyl ethers (PBDEs) in samples with different matrix compositions – Part 2: New approaches to PBDEs determination
PublicationHerein, we review the latest technical solutions for polybrominated diphenyl ethers (PBDEs) determination in samples with different matrix compositions, largely focusing on gas chromatography but also presenting some liquid chromatography–based solutions. Moreover, we discuss the use of diverse sample injection techniques while considering the advantages and disadvantages of each injection system in the context of PBDEs analysis....
-
Application of chromogenic dye in biogenic amines determination using spectrophotometry
PublicationBiogenic amines content can be the source of information in the field of freshness and suitability of certain foods for consumption. However, most analytical methods for their determination require complicated sample preparation and expert knowledge. Because of that, a novel approach based on chromogenic dye application was proposed. After the SN1 reaction of an amine with S 0378 dye, the absorbance of the solution was measured...
-
Determination and identification of organic acids in wine samples. Problems and challenges.
PublicationFor long time, organic acids were underestimated. However, during last two decades there is an increasing interest of natural compounds having antioxidant, antimicrobial and anti-inflammatory properties thus organic acids are very preferable. Wine stands as one of the sources of organic acids since they are responsible for its organoleptic and aestethic character. Nevertheless, it is important to not exceed acceptable level of...
-
Simple smartphone-based methods for the determination of bioactive compounds in wine
PublicationA set of simple smartphone-based methods of bioactive compounds determination were developed for wine analysis. Procedures for smartphone-based determination of the total content of phenolic compounds, flavonoids, anthocyanins and biogenic amines, as well as measurement of antioxidant activity were developed and fully validated. The experimental setup is based on smartphone and 3D-printed device, though it is very simple and can...
-
Determination of benzo(a)pyrene content in PM10 using regression methods
PublicationThe paper presents an attempt of application of multidimensional linear regression to estimation of an empirical model describing the factors influencing on B(a)P content in suspended dust PM10 in Olsztyn and Elbląg city regions between 2010 and 2013. During this period annual average concentration of B(a)P in PM10 exceeded the admissible level 1.5-3 times. Conducted investigations confirm that the reasons of B(a)P concentration...
-
New methodology for determination cationic surfactants in liquid environmental samples
PublicationBecause of their specific physical and chemical properties (e.g. amphiphilicity, solubility in polar and nonpolar liquids, ability to form micelles, adsorption at phase boundaries, low toxicity) surfactants (surface-active compounds) are widely applied in industry and in the household. As their applications are on a very large scale, it has become necessary to acquire a more detailed understanding of their environmental fate. Mainly,...
-
Determination of Local Corrosion Current from Individual Harmonic Components
PublicationHarmonic analysis has been used in corrosion measurements for several decades. During this period the method has been refined and developed. Nevertheless, the technique has not been applied to properties determination in local scale yet. This paper is focused on local corrosion current measurements based on harmonic analysis. For this purpose, a non-linear nature of electrode processes is used and measured in local scale applying...
-
Sample preparation techniques for determination of pesticide residues in food samples
PublicationPesticides are very important in increasing the efficiency and quality of agricultural production. They are applied in many spheres of life, not only in agriculture, and their applications are expanding. Despite their numerous merits, pesticides are some of the most toxic substances contaminating our environment and have a negative impact on the human health. Properties of pesticides such as stability, ability to bioaccumulation...
-
Determination of the active ingredient in pharmaceutical gel formulation by NIR spectroscopy
PublicationPharmaceuticals of their intended must be thoroughly controlled. The traditional analytical methods are very costly and time consuming. NIR spectroscopy allows to analyze pharmaceutical materials very quickly and with very low costs. First pharmaceutical applications of the NIR spectroscopy appeared with some incuriosity in the late 1960s. Application of NIR in the contemporary pharmaceutical industry is very large. The most common...
-
DETERMINATION OF SURFACTANTS IN ENVIRONMENTAL SAMPLES. PART II. ANIONIC COMPOUNDS
PublicationSurfactants (SAA) with negative charge of polar group are named as anionic compounds. They are main constituent of most products containing synthetic surfactants. The linear alkylbenzene sulfonates (LAS), alkyl ethoxysulfates (AES) and alkyl sulfates (AS) are typically applied from this class of compounds. Those surfactants are ingredients of household detergents and cleaners, laundry detergents, cosmetic. Moreover they can be...