From Thomson formula to resonant equivalent diagrams

Until the 1970s, only three basic elements: R, C, and L have been used to construct RLC circuits. These elements are two-ports of zero order (resistances) and of first order (capacitances and inductances). Their presence in electronic circuits causes a certain phase shift between voltage and current. In 1969, Bruton published an inductorless filter. There are two two-ports of second order (supercapacitances) in this circuit. Supercapacitance causes a phase shift of 180 degrees. In the next years, many two-ports of higher orders (e.g. of second and third order) were developed and, in theory, their number may be infinite. The use of such two-ports in resonant circuits makes it possible to obtain other phase shifts. In this paper, we show how to transform basic circuits into their resonant equivalent diagram. The analysis of these diagrams allows us to describe precisely resonant phenomena occurring in the circuit and to identify all resonant circuits, even when the basic diagram does not indicate resonance properties

Wpływ granulacji proszku na szybkość transportu i rozpuszczalność wodoru w materiale kompozytowym: proszek LaNi5-parafina

On the basis of potentiostatic discharge method, the diffusion rate of atomic hydrogen as well as its solubility in LaNi5 crystal lattice have been evaluated for three LaNi5 powder - paraffin composite electrodes, with different LaNi5 powder particle diameters: 0 - 20 η, 20 - 50 η and 50 - 100 η. The chronoamperommetric tests have been carried out in strong alkaline (6 M KOH), deaerated solution, at 25_C. Apparent hydrogen diffusion coefficients have been determined using Crank's spherical diffusion model. It has been shown, that increase of particle size is prone to increase of hydrogen apparent diffusion coefficient and to decrease of hydrogen concentration in the solid phase. To explain the granulation effect on hydrogenation ability parameters, the inhibition of hydrogen transport by surfacial corrosion products present on powder particles has been assumed.Za pomocą potencjostatycznej metody rozładowania oceniono szybkość dyfuzji atomowego wodoru i jego rozpuszczalność w sieci krystalicznej LaNi5 dla trzech elektrod kompozytowych: proszek LaNi5 - parafina przy różnych średnich rozmiarach cząstek LaNi5: 0 - 20 η, 20 - 50 η i 50 - 100 η. Badania chronoamperometryczne przeprowadzono w silnie zasadowym (6 M KOH), odpowietrzonym roztworze, przy 25 stopni Celsjusza. Pozorne współczynniki dyfuzji wodoru wyznaczono wykorzystując model sferycznej dyfuzji Crank'a. Pokazano, że wzrost rozmiarów cząstek proszku prowadzi do wzrostu wartości pozornego współczynnika dyfuzji w fazie stałej. Dla wytłumaczenia wpływu granulacji na parametry opisujące zdolność wodorownia założono, ze transport atomowego wodoru ulega spowolnieniu wskutek obecności powierzchniowych produktów korozji na cząstkach proszku

Assessment of water-bearing capacity of flysch deposits in the Muszyna region based on spring investigation

W pracy zaprezentowano wyniki badań hydrogeologicznych prowadzonych w rejonie Muszyny. Na podstawie analizy wyników badań naturalnych wypływów wód podziemnych, po uwzględnieniu budowy geologicznej i wyników badań hydrologicznych, oceniono wodonośność utworów fliszowych, co umożliwiło dyskusję na temat zmienności wodonośności na obszarze współwystępowania wód zwykłych i mineralnych.This paper present the results of hydrogeological studies conducted in the Muszyna region. Based on the results of the analysis of natural groundwater discharges, and taking into account the geological structure and the results of hydrological studies, the water-bearing capacity of flysch rocks has been rated. This allowed discussing the water-bearing capacity in the area of drinking and mineral water co-occurrence

Molecular fluorescent probes in biology, biochemistry and biotechnology

Nowadays molecular fluorescent probes are widely used in many fields of science, primarily in biology, medicine and biotechnology. Particular emphasis on the development of technologies to cancer cells diagnosis and detection of genetic mutations led to numerous modification of luminescent fluorophores, which has resulted in a wide range of such compounds. Scientists from around the world are continuously trying to experience the mechanism of cells function and metabolic pathways. Certainly, it is affected by the fact that any analytical techniques using fluorescence operate easily and nondestructively. A phenomenon of fluorescence is observable by chromophore which absorbs energy at a certain wavelength and is able to emit electromagnetic radiation at another wavelength