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1

Potential effects of electrical energy transmission : the case study from the Polish Marine Areas (southern Baltic Sea)

Otremba Zbigniew, Jakubowska Magdalena, Urban-Malinga Barbara, Andrulewicz Eugeniusz

Oceanological and Hydrobiological Studies

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2019

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Vol. 48, No. 2

196--208

EN

The operation of offshore wind turbines and electricity transmission through submarine cables over long distances generate electromagnetic or static magnetic fields (depending on the technical solution) that may modify the natural geomagnetic field and cause induced electric and electromagnetic fields in the water. The present study synthesizes the current knowledge and speculates on the possible environmental impact of electrical energy transfer based on the example of the Polish Marine Areas (southern Baltic Sea). We review the possible effects of the electrical energy induction and transfer against the existing and planned wind turbine installations. Furthermore, we consider different cable design variants as a way of environmental impact mitigation. Possible impacts of induced magnetic fields on marine organisms and, consequently, on the ecosystem functioning are also addressed.

2

O zjawiskach fizycznych decydujących o skuteczności przesyłu energii w systemach energetycznych

Czarnecki Leszek S.

Automatyka, Elektryka, Zakłócenia

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2019

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Vol. 10, nr 3(37)

8--15

PL

Skuteczność przesyłu energii w systemach energetycznych zależy od pewnej liczby zjawisk fzycznych temu towarzyszących. Ich obecność nie jest w środowisku elektrotechnicznym w pełni uświadamiana lub są one błędnie interpretowane. Gdy napięcia i prądy w systemie energetycznym są sinusoidalne oraz symetryczne, wówczas przyczyny zmniejszania skuteczności przesyłu energii są względnie dobrze znane i kojarzone są z obecnością mocy biernej. Nie jest już tak wtedy, gdy napięcia i prądy są odkształcone lub/i niesymetryczne. Tych zjawisk jest wówczas więcej. Większość z nich została zidentyfkowana w ramach teorii mocy opartej na koncepcji Składowych Fizycznych Prądów (ang.: Currents’ Physical Components (CPC)). Niniejszy artykuł niektóre te zjawiska opisuje i omawia.

EN

The eﬀectiveness of the energy transfer in electrical power systems depends on a number of physical phenomena. Their presence is not well recognized in the electrical engineering community, though; or they are wrongly interpreted. As long voltages and currents are sinusoidal and symmetrical, a reduction in the energy transfer eﬀectiveness is associated usually with a presence of the reactive power. However, when the voltages and currents are distorted and/or asymmetrical, then there are many more phenomena that can contribute to this eﬀectiveness decline. Majority of them were identifed in the frame of the Currents’ Physical Components (CPC)-based power theory. This paper describes and explains some of them.

3

Fotoaktywne układy polimerowe o rozmiarach nanometrycznych

Wróbel M. J.

Wiadomości Chemiczne

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2018

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[Z] 72, 5-6

279--297

EN

Sun is the most powerful source of clean, cheap and environmentally friendly source of energy, but still, the usage of this resource cover less than 1% of current world energy requirements [1]. However, nature realizes efficient conversion of solar energy to chemical energy on mass scale in different photoactivated processes like photosynthesis, which are essential for our life on this planet. The process takes place in green parts of plants with exceptional efficiency and precision. Natural photosystems like that attract attention to many researchers to develop artificial energy conversion devices. Many photoactive materials (polymers, nanostructures and small molecules) exhibiting high solar energy conversion and catalytic activity have been synthesized and rapidly applied in fields like pollutant removal [2] or solar cells [3]. Although significant development of artificial devices that can mimic natural processes have been achieved, their commercialization still remains a problem. Construction of molecular structure that can mimic natural photosystems is very challenging with regard to synthetic chemistry and impossibility of use the “top – down” methods which cannot reach the molecular level. Generally, photoactive materials have low stability and short lifetime due to their oxidative and aqueous degradation and decomposition under high intensity of light [4]. One of the most challenging problems during designing of artificial photosystems is directionality of excitation energy transfer along properly ordered chromophores. What is more, the mechanism of energy migration often cannot be described using well-known Förster or Dexter theories [5]. This work will focus on the selected artificial photosystems based on polymers. First, short theory of energy transport is presented, followed by description of devices based on multilayered films, repairable polymeric systems, nanohybrids of carbon nanotubes and photoactive polymers, light harvesting conjugated microporous polymers and polymer brushes.

4

Dynamics control of an autoparametric system with the spherical pendulum using mr damper

Sado D., Freundlich J.

Vibrations in Physical Systems

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2018

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Vol. 29

art. no. 2018016

EN

Dynamic properties of the three degrees of freedom autoparametric system with spherical pendulum including the magnetorheological (MR) damper are investigated. It was assumed that the spherical pendulum is suspended to the oscillator excited harmonically in the vertical direction. The influence of damping force described by Bingham’s model on the energy transfer can be modified by magnetic field. The equation of motion have been solved numerically. In this type system one mode of vibration may excite or damp another one, and for except different kinds of periodic vibrations there may also appear chaotic vibration. Results show that MR damper can be used to change the dynamic behavior of the autoparametric system with spherical pendulum giving semiactive control possibilities.

5

Gaz osłonowy: zwykły produkt czy narzędzie służące optymalizacji?

Matz C.

Przegląd Spawalnictwa

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2018

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R. 90, nr 6

6--9

PL

Spawacze często uważają, że wszystkie gazy osłonowe są zasadniczo identyczne, a zmiana gazu nie wywiera zauważalnego wpływu na spoinę. W rezultacie gaz osłonowy z reguły postrzega się jako nieuniknioną konieczność w procesach spawania w osłonie gazowej - jako towar, który można nabyć w dowolnym miejscu, za możliwie najniższą cenę. Ale czy naprawdę jedynym zadaniem gazów osłonowych jest ochrona jeziorka spawalniczego przed niepożądanym dostępem powietrza? Czy to prawda, że poszczególne gazy osłonowe można stosować zamiennie i że można kierować się najniższą ceną? Czy rzeczywiście obowiązuje tu prosta zasada, że zakup najtańszego rozwiązania generuje oszczędności? Jak wykazano w niniejszym artykule, gaz osłonowy ma w rzeczywistości bezpośredni wpływ na proces spawania, a jego precyzyjny dobór zawsze znacząco wpływa na jakość i wydajność procesu. W ten sposób gaz osłonowy staje się gazem technologicznym, a zło konieczne - cennym narzędziem. Korzyści płynące z właściwego doboru gazu technologicznego wyjaśniono na przykładach, począwszy od spawania metodą TIG aż po proces MAG-Tandem, od stali wysokostopowej aż po aluminium.

6

Excitability of high-energy ultraviolet radiation for Dy3+ in antimony phosphate glasses

Zhu C., Zhang J., Wang Z., Lin H.

Materials Science Poland

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2017

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Vol. 35, No. 2

346--354

EN

Dy3+ doped antimony phosphate (ZASP) glasses are synthesized and the specificity of the luminescence behavior is demonstrated. Different from the conventional long-wave ultraviolet (UVA) exciting cases, the excitable area of Dy3+ doped ZASP glasses is extended to high-energy ultraviolet radiation including medium-wave ultraviolet (UVB) and short-wave ultraviolet (UVC) spectral regions. The quantum efficiency for 4F9/2 level of Dy3+ in low- and medium-concentration Dy2O3 doping cases reaches 95.0 % and 66.7 %, respectively, confirming the emission effectiveness from Dy3+ in ZASP glasses. The values of energy-transfer probability (P) have obvious difference while using 340 nm and 540 nm as monitoring wavelengths, so asthe energy-transfer efficiencies (η), which are related to the energy-transfer processes from discrepant Sb3+ donors to Dy3+ acceptors, were in-equivalent. The effective excitability of high-energy ultraviolet radiation illustrates that Dy3+ doped ZASP glasses are a promising candidate in developing visible light sources, display devices and tunable visible lasers.

7

Influence of Parameters of Two Pendulums System With an Elastic Element on Regular and Chaotic Vibrations

Sado D., Brodowska E. T.

Machine Dynamics Research

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2017

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Vol. 41, No. 2

85--96

EN

In this work, a system with two degrees of freedom is studied, consisting of the two coupled pendulums, connected by the element characterized by linear elasticity of rigidity and linear damping. One of the pendulums is subjected to harmonic horizontal excitation. The equations of motion within the studied system are derived as Lagrange’s equations. For small vibrations it was assumed that displacement of the spring element is horizontal only. Exemplary results of the energy transfer, for different parameter values of the system are presented. Numerically, it was indicated that near the internal and external resonance, except different kinds of periodic vibrations, chaotic vibration may also occur. For characterizing an irregular chaotic response, the Poincare maps and maximal exponents of Lyapunov have been constructed.

8

Chaotic vibration of an autoparametrical system with the spherical pendulum

Sado D., Freundlich J., Bobrowska A.

Journal of Theoretical and Applied Mechanics

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2017

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Vol. 55 nr 3

779--786

EN

In the paper, the dynamics of a three degree of freedom vibratory system with a spherical pendulum in the neighbourhood of internal and external resonance is considered. It has been assumed that the spherical pendulum is suspended to the main body which is then suspended to the element characterized by some elasticity and damping. The system is excited harmonically in the vertical direction. The equation of motion has been solved numerically. The influence of initial conditions on the behaviour of the spherical pendulum is investigated. In this type of the system, one mode of vibration may excite or damp another one, and for different kinds of periodic vibrations there may also appear chaotic vibrations. For characterization of an irregular chaotic response, time histories, bifurcation diagrams, power spectral densities, Poincar´e maps and the maximum Lyapunov exponents have been calculated.

9

The dynamics of a coupled mechanical system with spherical pendulum

Sado D., Freundlich J., Dudanowicz A.

Vibrations in Physical Systems

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2016

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Vol. 27

309--316

EN

The nonlinear response of a three degree of freedom vibratory system with spherical pendulum in the neighbourhood internal and external resonance is investigated. It was assumed that spherical pendulum is suspended to the main body which is suspended by the element characterized by elasticity and damping and is excited harmonically in the vertical direction. The equation of motion have bean solved numerically. In this type system one mode of vibration may excite or damp another one, and for except different kinds of periodic vibrations there may also appear chaotic vibration.

10

Oscillations of an Autoparametrical Systems with the Spherical Pendulum

Sado D., Bobrowska A.

Machine Dynamics Research

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2016

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Vol. 40, No. 2

155--163

EN

Dynamic properties of the three degrees of freedom autoparametric system with spherical pendulum in the neighbourhood internal and external resonance are investigated. It was assumed that the spherical pendulum is suspended in the main body which is suspended by the element characterized by elasticity and damping and is excited harmonically in the vertical direction. The spherical pendulum is similar to the simple pendulum, but moves in 3-dimensional space, so the model with spherical pendulum is more similar to the real systems than the model with simply pendulum. In this paper the position of the main body is described by coordinate z and position of the pendulum is describe by the coordinate z and two angles: θ and φ in the vertical planes. This system has three degrees of freedom. Dynamic properties of the system described by three differential equations containing strongly nonlinear terms are investigated numerically. In autoparametric system one mode of vibration may excite or damp another one, and for except periodic or quasi-periodic vibrations there may also appear chaotic vibration. For characterizing an irregular chaotic response, time histories, bifurcation diagrams, power spectral densities, Poincaré maps and maximal exponents of Lyapunov have been developed.

11

Optical properties of Nd:YbVO4 crystal

Liu F Q, Sun S Q, Gao C Y, Xu J Q

Optica Applicata

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2015

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Vol. 45, nr 1

63—70

EN

Optical characteristics of a new laser crystal Nd:YbVO4 were studied. The optical parameters of a-cut and c-cut Nd:YbVO4 crystals were calculated by the Judd–Ofelt theory. The absorption crosssection of a-cut Nd:YbVO4 crystal was 5.34×10–20 cm2 at 808 nm, while it was 4.20×10–18 cm2 of c-cut Nd:YbVO4 crystal. The properties of energy transfer between Nd and Yb ions in Nd:YbVO4 crystal were discussed. In the fluorescence spectra, a peak at 472 nm appeared, which resulted from the coupling interaction between two Yb ions.

12

Enhanced luminescence of rare-earth Tb (III) obtained by mixing of Gd (III) in a fumarate complex and intra-molecular energy transfer

Shah M. D., Want B.

Materials Science Poland

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2015

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Vol. 33, No. 4

685--691

EN

Trivalent lanthanide ions display fascinating optical properties. Therefore, the rare-earth complexes of terbium fumarate heptahydrate and GdTb fumarate heptahydrate were grown by using a single gel diffusion technique. The crystals were characterized by different physicochemical techniques of characterization. UV-Vis and photoluminescence spectrophotometric experiments were carried out to study the optical properties of the grown crystals. Under various excitations (339 nm, 350 nm or 368 nm) the terbium fumarate complex emitted characteristic (4f-4f) green emission of Tb3+ (5D4)-7FJ J = 6, 5, 4 and 3, respectively). Luminescence spectra showed that Gd3+ ions in the mixed complex have not affected the luminescence emission peak positions, but remarkably increased the luminescent intensities of the terbium complex. The energy-transfer mechanism between the ligand and the central Tb3+ ions and from the Gd3+ to the Tb3+ was discussed.

13

Synthesis and phosphorescent properties of the copolymers of N-vinylcarbazole, methyl methacrylate and iridium complex

Wang W., Zhou M., Liang L, Lin M, Ling M

Materials Science Poland

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2014

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Vol. 32, No. 2

206--213

EN

The copolymers containing carbazole unit and iridium complexes, such as (Ir(bpy)2Cl, Ir(mbpy)2Cl and Ir(Brbpy)2Cl, were synthesized via radical copolymerization of N-vinylcarbazole, methyl methacrylate and iridium complex. The synthesized copolymers were characterized by FT-IR, UV-Vis absorption spectroscopy and photoluminescence (PL) spectroscopy, respectively. According to the results, the copolymers (Ir(Brbpy)2Cl/PVK and Ir(mbpy)2Cl/PVK) exhibit yellow phosphorescence with an emission peak at around 553 nm under UV-visible light in the solid state. The results also reveal almost complete energy transfer from the host carbazole segments to the guest Ir complex in the copolymer film when the Ir content reaches 1.0 wt.%. The synthesized copolymers are good candidates as blue or yellow phosphorescent materials for PLED applications.

14

Active glasses as the luminescent sources of radiation for sensor applications

Żmojda J., Dorosz D., Kochanowicz M., Dorosz J.

Bulletin of the Polish Academy of Sciences. Technical Sciences

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2014

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Vol. 62, nr 2

393--397

EN

The article presents physicochemical, thermal and spectroscopic properties of two different glass systems: TeO2-GeO2-PbO-PbF2- BaO-Nb2O5-LaF3 and SiO2-Al2O3-Sb2O3, co-doped with Yb3+/Tm3+ ions. Blue upconversion luminescence at a wavelength of 478 nm corresponding to the thulium 1G4 ⇥3H6 transition was observed under 976 nm pump radiation in both of the co-doped glasses. This indicated the existence of efficient Yb3+ ⇥ Tm3+ energy transfer via three-photon absorption mechanism. Thermal and optical results substantiate the claim for practical applicability of the manufactured glasses in design of optical fiber sources.

15

Semi-analytical methods for optimal energy transfer in RC ladder networks

Baranowski J., Mitkowski W.

Przegląd Elektrotechniczny

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2012

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R. 88, nr 9a

250-254

EN

This paper presents a semi-analytical solution to the optimal control problem arising with energy transfer through transmission line. Distributed parameter RC line is approximated with a RC ladder network. Formulas for optimal control are determined up to a moment when matrix exponential has to be computed. This final element has to be computed numerically. Paper ends with results of simulations and a discussion of numerical issues.

PL

Praca przedstawia semi-analityczne rozwiązanie problemu sterowania optymalnego występującego przy przesyle energii poprzez linię długą. Linia długa RC jest aproksymowana za pomocą układu łancuchowego typu RC. Wzory okreslaja˛ce sterowanie optymalne są wyznaczone do momentu konieczności wyliczenia eksponenty macierzy. Ta część obliczeń musi być wykonana numerycznie. Praca kończy się wynikami symulacji i dyskusją zagadnień numerycznych.

16

Przekształtnikowy system transmisji energii ze źródła DC o niskim napięciu do sieci energetycznej

Jałbrzykowski S., Citko T.

Przegląd Elektrotechniczny

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2012

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R. 88, nr 4b

87-92

PL

W artykule przedstawiono dwie wersje układu przekształtnikowego umożliwiającego transmisję energii pomiędzy źródłem prądu DC o niskim poziomie napięcia do sieci energetycznej Przesył energii i przełączanie łączników obu przekształtników wspomagane jest przez zastosowany szeregowo-równoległy obwód rezonansowy. Sterowanie transmisją energii odbywa się przez zmianę częstotliwości, przy zachowaniu stałego czasu wyłączenia łączników. Własności i różnice zaprezentowanych układów zostaną u udokumentowane wynikami badań symulacyjnych i laboratoryjnych.

EN

The energy transfer from the low voltage DC source to power grid using alternatively two versions of the DC-DC converters is discussed in the paper. The both versions of the converter are controlled by frequency changes with constancy of the transistor switch off time and both have a series parallel resonance circuit included. The properties and differences of the both presented propositions are documented by simulations and laboratory investigations results.

17

Electrical energy in the future. A vision of 2050

Królikowski S., Walczak B., Wójcik A., Aftański A.

Acta Energetica

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2012

|

nr 3

85--99

EN

The article contains scenarios for the power sector’s development until 2050, as proposed by students of Electrical High School No. 4 in Wloclawek. Many current trends in the development of technology have led the authors to attribute the verisimilitude to their selected visions of the future. The growing demand for energy, while fossil fuel resources and traditional methods of processing them are shrinking, will cause dissemination of the use of so-called environment-friendly sources of energy, such as wind or biomass. Energy will be commonly converted in domestic power stations equipped with energy storage capabilities and integrated with the grid by smart controllers for two-way energy transfer. The power grid role will change, and the existing energy consumers will become its prosumers. In the opinion of the authors the only alternative for this power sector development vision may be thermonuclear generation, which requires, however, incredibly high capital expenditures and level of technological development. However, launching thermonuclear power plants would free humanity from the fear of a future predominated by energy crisis.

PL

Uczniowie Technikum nr 4 w Zespole Szkół Elektrycznych we Włocławku przedstawiają scenariusze rozwoju elektroenergetyki do 2050 roku. Wiele aktualnych tendencji w rozwoju techniki skłoniło autorów do nadania wybranym wizjom przyszłości cech prawdopodobieństwa. Rosnące zapotrzebowanie na energię, przy jednoczesnym kurczeniu się zasobów paliw kopalnych i tradycyjnych metod ich przetwarzania, spowoduje rozpowszechnienie wykorzystania tzw. źródeł ekologicznych energii, takich jak wiatr lub biomasa. Przetwarzanie energii będzie się odbywało powszechnie w przydomowych stacjach energetycznych wyposażonych w możliwość gromadzenia energii i zintegrowanych z siecią energetyczną za pomocą inteligentnych sterowników służących do dwukierunkowego transferu energii. Zmieni się rola sieci elektroenergetycznej, a dotychczasowi odbiorcy energii będą się stawali jej prosumentami. W odczuciu autorów artykułu alternatywą dla takiej wizji rozwoju elektroenergetyki może być jedynie energetyka termojądrowa, która wymaga jednak nieprawdopodobnie wysokich nakładów i poziomu rozwoju technologicznego. Uruchomienie elektrowni termojądrowych uwolniłoby jednak ludzkość od obaw o przyszłość zdominowaną kryzysem energetycznym.

18

Efektywna głębokość wnikania ciepła w przegrodzie pełnej wypełnionej MFZ

Heim D.

Zeszyty Naukowe Politechniki Rzeszowskiej. Budownictwo i Inżynieria Środowiska

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2011

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z. 58, nr 3/III

99-106

PL

W pracy omówiono termiczne zachowanie się płaskiego zbiornika wypełnionego materiałem fazowo-zmiennym i poddanego oddziaływaniu środowiska zewnętrznego. Przeanalizowano wpływ promieniowania słonecznego na ściany zbiornika oraz zawarty w nim materiał w przypadku, gdy kontener usytuowano pionowo i zorientowano na południe. Oceniano zdolność elementu do pasywnego magazynowania energii promieniowania słonecznego w cyklu dobowym w zależności od docierającego, całkowitego promieniowania słonecznego oraz dobowej różnicy temperatury. W obliczeniach zastosowano autorski model obliczeniowy w formie jawnej. Dyskretyzację w przestrzeni dokonano metodą objętości skończonych. Krok czasowy obliczeń przyjęto równy l godzina, zaś warunki brzegowe opisano poprzez 6 parametrów klimatu. Uwzględniono wymianę ciepła na drodze konwekcji, promieniowania oraz transport ciepła w materiale na drodze przewodzenia. Wyniki zamieszczono w postaci zmian temperatury na grubości przegrody dla charakterystycznych okresów czasu. Okresowe przebiegi w poszczególnych punktach przegrody opracowano pod względem statystycznym. Stwierdzono, że najefektywniejszą grubością przegrody o zadanych parametrach materiałowych praz dla danych warunków klimatycznych, z uwzględnieniem przemiany fazowej, jest grubość do 5 cm.

EN

The thermal behavior of the flat container filled with phase-change material exposed to the external environment is presented. The influence of solar radiation on the wall and the material contained therein when the container was situated vertically and oriented to the south was analyzed. The ability of passive solar energy storage in the daily cycle, depending on the total solar radiation and diurnal temperature difference was discussed. The calculation have been done using advanced numerical techniques. Time step calculation was equal to one hour, and the boundary conditions were described by six parameters of the local climate, based on TMY for Lodz. All heat transfer forms: by convection, radiation and heat transfer in the material by conduction were taking into account. The results are presented in the form of temperature changes in the wall for specific periods of time. Additionally, temperature change at particular nodes in the wall was work out statistically. It was found that the most effective barrier thickness of given parameters of material and climatic conditions, including the phase changes is the thickness of 5 cm.

19

Up-conversion fluorescence dynamics in Er3+/Yb3+ co-doped tellurite glasses

Cherif A., Kanoun A., Maaref H.

Optica Applicata

|

2011

|

Vol. 41, nr 1

235--245

EN

The infrared to visible conversion in zinc tellurite glasses (TZG), activated by Er3+ ions and sensitized by Yb3+ ions, has been investigated under 980 nm pulsed laser excitation. The up-conversion mechanism was studied by means of time-resolved luminescence spectroscopy. A model for the dynamics of frequency up-conversion in Er3+/Yb3+ co-doped TZG based on the rate equations was proposed. The dynamics of the up-converted emissions were studied to evaluate energy rates between Er3+ and the Yb3+ ions, and the rate excited state absorption (ESA) in Er3+ ions.

20

Analysis of Nd3+/Yb3+ ions energy transfer in oxyfluoride silicate glass for optical fibre ASE source

Dorosz D., Żmojda J., Kochanowicz M., Dorosz J.

Materiały Ceramiczne

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2011

|

T. 63, nr 1

44-47

EN

The paper presents optimisation of Nd3+/Yb3+ ratio to enhance the emission bandwidth at 1 µm. Analysis of the energy transfer scheme between Nd3+ and Yb3+ ions incorporated in oxyfluoride glass was performed. The highest efficiency (60 %) was measured for the equalvalues of absorption cross-section (Yb3+) and emission cross-section (Nd3+). The emission spectrum with 100 nm bandwidth of the Nd3+/Yb3+ co-doped glass samples under excitation at 808 nm was determined. The fabricated glass with the highest efficiency of energy transfer Nd3+--Yb3+ was used as a core in helical core double clad optical fibre.

PL

Artykuł przedstawia optymalizację stosunku Nd3+/Yb3+ w celu zwiększenia szerokości pasma przy 1 µm. Przeprowadzono analizę schematu przekazywania energii pomiędzy jonami Nd3+ i Yb3+ wprowadzonymi do szkła tlenofluorkowego. Największą efektywność (60 %) zmierzono w przypadku równych wartości przekrojów czynnych na absorpcję (Yb3+) i emisję (Nd3+). Określono widmo emisyjne o szerokości pasma 100 nm w przypadku próbek szkła współdomieszkowanego jonami Nd3+ i Yb3+ wzbudzanych przy 808 nm. Wytworzone szkło o najwyższej efektywności przekazywania energii Nd3--Yb3+ wykorzystano jako rdzeń w światłowodzie typu double-clad o rdzeniu spiralnym.