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PL
Precyzyjne sformułowanie określenia "chemicy analitycy" jest oczywiście bardzo trudne w sposób ścisły. Przede wszystkim trzeba zdawać sobie sprawę, że sam termin "chemia analityczna" jest trudny do określenia, gdyż ogromna większość czynności wykonywanych przez chemików wiąże się z jakościowym, a następnie ilościowym charakteryzowaniem badanego obiektu, niezależnie od tego, jakie będą dalsze cele działania i dalsze kroki naszego postępowania. Niemniej w potocznym znaczeniu tego zwrotu chemikowi analitykowi chodzi o to, aby jak najdoskonalej określić, "z czym mamy do czynienia?", a następnie, "ile tego jest?". Dlatego prawdopodobnie spotkam się z uwagami, że wspominam badaczy, którzy poczuliby się urażeni, że zaliczyłem ich do analityków, jak też nie omawiam tych, którzy by na szerszą wzmiankę zasługiwali.
EN
Application of magnesium selective electrodes to magnesium ion determination in biomedical samples has been introduced to analytical chemistry since 1990- ies. Using ion selective electrode, the ionized magnesium concentration is determined. Until this time, mainly concentration of total magnesium was determined. In this work, the importance of magnesium and its role in the human organism is shortly presented. Then, we present basics of ion selective electrodes and their application in clinical analyzers. We show exemplary applications of ionized and total magnesium concentration determination in clinical samples, such as blood serum or plasma and erythrocytes, in healthy people and in patients with various diseases. In every case, the ionized magnesium concentration in erythrocytes appears to be the most sensitive indicator of hypomagnesemia that is the pathophysiologically lowered magnesium level in organism. The knowledge of this parameter allows physicians for better diagnosis of magnesium status in human organism.
3
Content available remote Polish analytical chemistry – its history since 1945
EN
After World War II, the analytical chemistry, as many other fields of science, required rebuilding from bases, both in terms of the research staff, as well as, the laboratory facilities. This paper discusses the emergence of new academic centres and organizational structures of the Committee of Analytical Chemistry of the Polish Academy of Sciences, whose mission was a scientific co-operation enabling the retrieval of new research achievements, representing a lasting contribution to the global achievements of analytical chemistry. This paper also includes the presentation of the most important achievements of the Committee of Analytical Chemistry and the activities of 17 late researchers, analytical chemists, and in particular of Wiktor Kemula, Jerzy Minczewski and Andrzej Waksmundzki.
4
Content available remote Chemia analityczna w pracach Marii Skłodowskiej-Curie
EN
Maria Skłodowska-Curie - a Nobel Prize winner in chemistry - the elements of learning of chemistry gained just by a dint of work of more than ten months in Warsaw in the Institute of Industry and Agriculture Museum. The Nobel Prize concerned a contribution to the progress of chemistry through the discovery of radium and polonium, separation of radium and study of properties of this amazing element. It was awarded for an extremely arduous work, during which the chemical reactions being the principles of analytical chemistry were realized. Unlike to a typical analytical procedure, an initial attempt here was the thousands of kilograms of uranium ore: pitchblende. The final effect was small amounts of new elements: polonium and radium. Both the knowledge and the intuition of the researcher let her have a triumph. The difficulties she experienced because the properties of the searched chemical elements could only be evaluated thanks to the knowledge on other chemical elements. A significant achievement was the determination of the samples by means of radioactivity measurement, which gave rise to radiochemical analytical methods. An extreme analytical precision was demanded in multiple processes of fractional crystallization and precipitation which finally led to the calculation of the atomic mass of radium.
5
Content available remote Non-glass pH potentiometric sensors
EN
In the review the most important facts concerning the development of non-glass potentio-metric pll sensors has been presented. Among the discussed topics were metal and metal oxide electrodes, ion-selective field efTect transistors (ISFETs), conventional ionophore based pH electrodes, ionophore based pH electrodes with solid contact and enzyme biosensors based on pH electrodes. In these groups of sensors their main advantages and drawbacks were presented as well as some of their applications, in particular, in biomedical analysis. However, it should be remembered that in most cases the classical pH glass electrode is used as the ultimate reference.
PL
Omówiono najważniejsze fakty związane z konstrukcją i używaniem nieszklanych potencjometrycznych czujników pH. Wśród omawianych czujników omówiono elektrody metal/ tlenek metalu, jonoselektywne tranzystory polowe, elektrody pH z jonoforem w układzie konwencjonalnym oraz stałym kontaktem jak również bioczujniki enzymatyczne konstruowane na elektrodach pH. W tych grupach czujników wykazano ich zalety i wady. a także niektóre zastosowania zwłaszcza w analizie biomedycznej. Należy też wskazać, że ostatecznym układem odniesienia pozostaje klasyczna szklana elektroda pehametryczna.
6
Content available remote Dzieje chemii analitycznej w Polsce do roku 1945
EN
The present paper was divided into two parts. In the first part were discussed the achievements of Polish chemists, who worked out grounds for the development of analytical chemistry that began with winning back the independence in 1918. In the second part were presented the results of searches that were taken up in Poland in the interwar period. The activity in this time recurrently turned out to be a reason for its reactivating after 1945. The most significant achievements were confirmed by representative references to publications.
EN
The effect of digestion of road dust in the mixture of aqua regia + HF and of the leaching of the analytes with aqua regia only on the determination of Pt and Pd applying ICP-MS technique has been investigated. In order to eliminate spectral interferences in mass spec-trometry. mathematical correction was applied, as well as the interferents were separated from the analytes on a Dowex 50 WX-8 cation-exchange resin. It has been, found that after addition of HF, Hf and Y are transformed into stable fluoride compounds, which are not retained on the cation-exchanger and cause some interferences in the determination step. Leaching of the analytes with aqua regia without complete sample dissolution resulted in the release of Pt and Pd from the road dust. Noteworthy, the analytes were present in the sample in the form suitable for their separation on cation exchanger. The correctness of the applied procedure was confirmed via analysis of certified reference material BCR-723.
PL
Zbadano wpływ sposobu rozkładu próbek pyłu drogowego na oznaczanie Pt i Pd metodą spektrometrii mas z jonizacją w plazmie indukcyjnie sprzężonej (ICP-MS). W celu wyeliminowania interferencji spektralnych zastosowano metodę korekcji matematycznej w spektrometrii mas oraz oddzielanie analitów od pierwiastków inter ferujących (Hf, Y) na kationicie Dowex 50 WX-8. Stwierdzono, że zastosowanie do mineralizacji HF powoduje tworzenie się trwałych połączeń fluorkowych Hf i Y, które nie zatrzymywane na kationicie są przyczyną interferencji w etapie oznaczania. Ługowanie analitów wodą królewską zapewnia ilościowe uwolnienie Pt i Pd z pyłu drogowego, jak również występowanie analitów i pierwiastków interferujących w formie odpowiedniej do ich rozdzielania na kationicie. Poprawność proponowanej procedury potwierdzono analizując certyfikowany materiał referencyjny BCR-723.
9
Content available remote Jaroslav Heyrovsky (1890-1967)
PL
Badanie wielu reakcji chemicznych, kinetyki reakcji, wyznaczanie parametrów tych reakcji, stałych równowagi wymaga bardzo precyzyjnej kontroli warunków pH. Ważne jest, aby chemik, a zwłaszcza analityk, zdawał sobie sprawę z zagrożeń, które mogą mu grozić przy tak pozornie prostej operacji chemicznej, jaką jest pomiar pH.
13
Content available remote Profesor Wiktor Kemula i jego rola w chemii analitycznej i elektroanalizie
EN
The period activity of Professor Wiktor Kemula in science coincided with the rapid development of chemistry, and particularly of electrochemistry and analytical chemistry. His early stay in the Herkovsky’s laboratory in Prague was specially fruitful in further research fields of Kemula. He contributed to several fundamental electrochemical concepts and later, in Lwow and in Warsaw, this was the main trend in his work. Among the main achievements are usually mentioned the creation of the new analytical techniques: chromato-polarography and the cyclic voltammetry with the stationary mercury drop electrode. The former, which combines the elements of separation and determination techniques into one coherent system, can be treated as a prototype of contemporary common coupled (or hyphenated) techniques, which became nearly a standard in complex analytical investigations. The latter developed continuously since the initial Kemula works, and is now termed stripping (or inverse) voltammetry. It is one of the most sensitive electroanalytical techniques, one of the cornerstones in inorganic trace analysis. In analytical chemistry Professor Kemula has foreseen that the quality problem is the basic one and has indicated the necessity of controlling the analytical results by parallel determinations using basically different methods. He also paid much attention to the study of analytical procedures, which, beside of sound theoretical basis, should found an immediate application in practice. Professor Wiktor Kemula was also much interested in teaching at the University, being involved in lecturing, inspecting the students laboratories, and improving the teaching programmes. He laid foundation of the Committee on Analytical Chemistry of the Polish Academy of Sciences, being its Chairman, and was a co-organiser of the Polish journal on analytical chemistry „Chemia Analityczna” and for many years its Editor-in-Chief.
19
Content available remote Low-level measurements with ion-selective electrodes
EN
One of the most important parameters describing analytical usefulness of ion-selective electrodes (ISEs) is the limit of detection. Until now for almost all ISEs the achievable detection limit in non-complexing solutions was 10(-6)-10(-5) mol/l. This relatively high value indicated limitations of ISEs applicability to many analytical tasks. Recently it has been shown that by proper adjustment of ion-selective electrode's inner filling solution the value of the detection limit can be shifted down even by 6 orders of magnitude. This discovery can open new perspectives for ion-selective measurements e.g., in clinical and environmental analysis.
PL
Granica wykrywalności jest jednym z najważniejszych parametrów opisujących analityczną przydatność elektrod jonoselektywnych (ISE). Do tej pory dla prawie wszystkich ISE osiągana granica wykrywalności wynosiła 10(-6)-10(-5) mol/l. Ta względnie wysoka wartość wskazywała na ograniczenie możliwości zastosowania ISE do wielu celów analitycznych. Stwierdzono, że poprzez odpowiednie dobranie składu roztworu wewnętrznego w elektrodzie jonoselektywnej granica wykrywalności może być obniżona nawet o 6 rzędów wielkości. To odkrycie może otworzyć nowe perspektywy dla pomiarów za pomocą elektrod jonoselektywnych np. w analizie klinicznej czy środowiskowej.
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