138 results on '"R. Lisiecki"'
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102. Spectroscopic and Thermographic Qualities of Praseodymium-Doped Oxyfluorotellurite Glasses.
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Klimesz B, Ryba-Romanowski W, and Lisiecki R
- Abstract
The thermal stability of oxyfluorotellurite glass systems, (65-x)TeO
2 -20ZnF2 -12PbO-3Nb2 O5 -xPr2 O3 , doped with praseodymium was examined. The different concentrations of praseodymium oxide (x = 0.5 and 2 mol%) were applied to verify the thermal, optical and luminescence properties of the materials under study. The relatively high values of the Dietzel (ΔT) and Saad-Poulain (S or H') thermal stability factors determined using a differential thermal analysis (DTA) indicate the good thermal stability of the glass matrix, which gradually improves with the content of the active dopant. The temperature dependence of optical spectra in the temperature range 300-675 K for the VIS-NIR region was investigated. The involved Pr3+ optical transition intensities and relaxation dynamic of the praseodymium luminescent level were determined. The ultrashort femtosecond pulses were utilized to examine a dynamic relaxation of the praseodymium luminescent levels. Although the measured emission of the Pr3+ active ions in the studied glass encompasses the quite broad spectral region, the observed luminescence may only be attributed to3 PJ excited states. As a result, the observed decrease in the experimental lifetime for the3 P0 level along with the increasing activator content was identified as an intensification of the Pr-Pr interplay and the associated self-quenching process. The maximum relative sensitivities (Sr ) estimated over a relatively wide temperature range are ~0.46% K-1 (at 300 K) for FIR (I530 /I497 ) and 0.20% K-1 (at 600 K) for FIR (I630 /I497 ), which seems to confirm the possibility of using investigated glasses in optical temperature sensors.- Published
- 2024
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103. UVC Stokes and Anti-Stokes Emission of Ca 9 Y(PO 4 ) 7 Polycrystals Doped with Pr 3+ Ions.
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Lemański K, Bezkrovna O, Rebrova N, Lisiecki R, Zdeb P, and Dereń PJ
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The recent COVID-19 pandemic has made everyone aware of the threat of viruses and the growing number of antibiotic-resistant bacteria. It has become necessary to find new methods to combat these hazards. One tool that could be used is UVC radiation, i.e., 100-280 nm. Currently, the available sources of this light are mercury vapor lamps. However, the modern world requires more compact, mercury-free, and less energy-consuming light sources. This work presents the results of our research on a new material in which efficient UVC radiation was obtained. Here, we present the results of research on Ca
9 Y(PO4 )7 polycrystals doped with Pr3+ ions prepared using the solid-state method. The absorption, excitation, emission, and emission decay profiles of praseodymium(III) ions were measured and analyzed. The upconversion emission in the UVC region excited by blue light was observed. Parameters such as energy bandgap, refractive index, and thermal stability of luminescence were determined. The studied phosphate-based phosphor possesses promising characteristics that show its potential in luminescent applications in future use in medicine or for surface disinfection.- Published
- 2024
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104. UVC Up-Conversion and Vis-NIR Luminescence Examined in SrO-CaO-MgO-SiO 2 Glasses Doped with Pr 3 .
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Bezkrovna O, Lisiecki R, Macalik B, and Dereń PJ
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The application of ultraviolet-C light in the field of surface treatment or photodynamic therapy is highly prospective. In this regard, the stable fluorescent silicate SrO-CaO-MgO-SiO
2 -Pr2 O3 glasses able to effectively convert visible excitation on the ultraviolet praseodymium emission were fabricated and examined. An unusual wide-range visible-to-UVC up-conversion within 240-410 nm has been achieved in Pr3+ -doped glasses, revealing their potential advantage in different sophisticated disinfection technologies. The integrated emission intensity was studied as a function of light excitation power to assess a mechanism attributed to UVC luminescence. Especially, it was revealed that the multicomponent silicate glass qualities and praseodymium3 PJ excited state peculiarities are favorable to obtaining useful broadband ultraviolet up-converted luminescence. The glass dispersion qualities were determined between 450-2300 nm. The impact of praseodymium concentration on Vis-NIR spectroscopic glass qualities was evaluated employing absorption spectra, emission spectra, and decay curves of luminescence associated with two involved praseodymium excited states. Especially, efficient interionic interactions can be inferred by investigating the decrease in1 D2 state experimental lifetime in the heavily doped samples. Examination of absorption spectra as a function of temperature implied that excitation at 445 nm should be quite effective up to T = 625 K. Contrary to this, temperature elevation gives rise to a moderate lowering of the visible praseodymium luminescence.- Published
- 2024
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105. Luminescence Properties of an Orthorhombic KLaF 4 Phosphor Doped with Pr 3+ Ions under Vacuum Ultraviolet and Visible Excitation.
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Zdeb P, Rebrova N, Lisiecki R, and Dereń PJ
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Fluorides have a wide bandgap and therefore, when doped with the appropriate ions, exhibit emissions in the ultraviolet C (UVC) region. Some of them can emit two photons in the visible region for one excitation photon, having a quantum efficiency greater than 100%. In a novel exploration, praseodymium (Pr
3+ ) ions were introduced into KLaF4 crystals for the first time. The samples were obtained according to a high-temperature solid-state reaction. They exhibited an orthorhombic crystal structure, which has not been observed for this lattice yet. The optical properties of the material were investigated in the ultraviolet (UV) and visible ranges. The spectroscopic results were used to analyze the Pr3+ electronic-level structure, including the 4 f 5 d configuration. It has been found that KLaF4 :Pr3+ crystals exhibit intense luminescence in the UVC range, corresponding to multiple 4 f → 4 f transitions. Additionally, under vacuum ultraviolet (VUV) excitation, distinct transitions, specifically1 S0 →1 I6 and3 P0 →3 H4 , were observed, which signifies the occurrence of photon cascade emission (PCE). The thermal behavior of the luminescence and the thermometric performance of the material were also analyzed. This study not only sheds light on the optical behavior of Pr3+ ions within a KLaF4 lattice but also highlights its potential for efficient photon management and quantum-based technologies.- Published
- 2024
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106. Conformation of the hydrazo bond in new 2-methyl-3,5-dinitro-6-(2-phenylhydrazinyl)pyridine and its influence on the structural and optic properties - Quantum chemical DFT calculations.
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Michalski J, Stoczewski Z, Roszak S, Kucharska E, Bryndal I, Dymińska L, Lisiecki R, and Hanuza J
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A new methyl-dinitro-phenylhydrazinyl-pyridine derivative [2-methyl-3,5-dinitro-6-(2-phenylhydrazinyl)pyridine] was synthesised and characterised by means of structural and spectroscopic measurements. The X-ray diffraction studies revealed that the compound crystallises in the centrosymmetric monoclinic space group P2
1 /n, with two symmetry-independent molecules in the asymmetric unit with Z = 8. Hydrazo bridge C-NH-NH-C links two fragments composed of phenyl ring and pyridine unit substituted with methyl and nitro groups. Such a structure was confirmed by1 H and13 C NMR studies as well as IR, Raman, UV-Vis, and emission spectra. The results were analysed using the quantum-chemical DFT calculations. The paper reports the vibrational characteristics and discusses dynamical properties of this moiety. The full set of the normal modes typical of the hydrazo bridge was identified and assigned to respective IR and Raman bands. The results of structural and spectroscopic studies were used to find the dependence between the conformation of the θ-NH-NH-ϕ system and its optic properties. The experimental UV-Vis and emission spectra were discussed in terms of the calculated singlet and triplet states that allowed assigning the unique spectral pattern originating from the electrons of the hydrazo-bridge system., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 Elsevier B.V. All rights reserved.)- Published
- 2024
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107. Structural, spectroscopic properties ant prospective application of a new nitropyridine amino N-oxide derivative: 2-[(4-nitropyridine-3-yl)amino]ethan-1-ol N-oxide.
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Godlewska P, Sąsiadek W, Kucharska E, Ropuszyńska-Robak P, Dymińska L, Janczak J, Lisiecki R, Ptak M, and Hanuza J
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A new nitropyridine amino N-oxide derivative 2-[(4-nitropyridine-3-yl)amino]ethan-1-ol N-oxide was synthesized and its structural and optical properties were described. Its structure obtained from the X-ray diffraction (XRD) studies was related to the Infrared spectroscopy (IR), Raman spectroscopy (RS), electron Ultraviolet-Visible spectroscopy (UV-VIS) and emission spectra measurements. The experimental results were analyzed in terms of theoretical data obtained from quantum chemical Density Functional Theory (DFT) and Natural Bond Orbital (NBO) calculations. The 6-311G(2d,2p) basis set with the B3LYP functional was used to discuss its optimized structure and vibrational properties. Femtosecond excitation was used to recognize the depopulation mechanism of the electron excited states in the studied compound. It was found that the intermolecular interactions strongly influence the physicochemical properties and application of the new nitropyridine amino N-oxide derivative., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023. Published by Elsevier B.V.)
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- 2024
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108. Spectroscopic and optical properties of 1,2,4-triazolo[4,3-a]pyridin-3(2H)-one as a component of herbicides.
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Dymińska L, Hanuza J, Janczak J, Ptak M, and Lisiecki R
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The herbicides azafenidin [(2-(2,4-dichloro-5-prop-2-ynoxyphenyl)-5,6,7,8-tetrahydro-[1,2,4]triazolo[4,3-a]pyridin-3-one)] and flumetsulam [(N-(2,6-difluorophenyl)-5-methyl-[1,2,4]triazolo[1,5-a]pyrimidine-2-sulfonamide)] were subjected to IR, Raman, UV-Vis and emission studies. As triazolopyridine is the most prominent and active component of these herbicides, this molecule was characterised by XRD studies, FTIR, Raman, UV-Vis and emission spectra. The experimental data were compared to the results of the DFT quantum chemical calculations carried out for its optimised structure, IR intensities and Raman activities, HOMO-LUMO transitions, and energies of the singlet and triplet states. The characteristics for triazolopyridine quantities were used in the analysis of the studied herbicides., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 Elsevier B.V. All rights reserved.)
- Published
- 2023
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109. Chitosan and Its Carboxymethyl-Based Membranes Produced by Crosslinking with Magnesium Phytate.
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Zając A, Sąsiadek W, Dymińska L, Ropuszyńska-Robak P, Hanuza J, Ptak M, Smółka S, Lisiecki R, and Skrzypczak K
- Abstract
Membranes produced by crosslinking chitosan with magnesium phytate were prepared using highly deacetylated chitosan and its N -carboxymethyl, O -carboxymethyl and N , O -carboxymethyl derivatives. The conditions of the membrane production were described. IR, Raman, electron absorption and emission spectra were measured and analyzed for all the substrates. It was found that O -carboxymethyl chitosan derivative is the most effectively crosslinked by magnesium phytate, and the films formed on this substrate exhibit good mechanical parameters of strength, resistance and stability. Strong O-H···O hydrogen bonds proved to be responsible for an effective crosslinking process. Newly discovered membrane types produced from chitosan and magnesium phytate were characterized as morphologically homogenous and uniform by scanning electron microscopy (SEM) and IR measurements. Due to their good covering properties, they do not have pores or channels and are proposed as packaging materials.
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- 2023
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110. Broadband near-infrared luminescence properties of Sc 2 (MoO 4 ) 3 :Cr 3+ molybdates.
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Stefańska D, Kabański A, Adaszyński M, Ptak M, Lisiecki R, Starościk N, and Hanuza J
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The structural and spectroscopic properties of Sc
2 (MoO4 )3 molybdate containing various concentrations of Cr3+ ions were investigated in a temperature range of 80-300 K. The samples were prepared using hydrothermal as well as solid-state reaction methods. The influence of synthesis conditions and the molybdenum source on the structural properties was studied by X-ray diffraction (XRD), IR (infrared), and Raman methods. The optical properties of Sc2 (MoO4 )3 samples doped with 0.1, 0.5, 1.0, and 2.0 % of Cr3+ ions were investigated. The broadband near-infrared (NIR) luminescence spectra generated from the4 T2 and2 E levels of Cr3+ ions may be attractive for NIR light-emitting diode (LED) applications. Emission decay profiles and the crystal field parameters of Cr3+ ions are discussed. In particular, the mechanism of photoluminescence generation and the thermal quenching path are described in detail., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 Elsevier B.V. All rights reserved.)- Published
- 2023
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111. Exploring Structure-Sensitive Factors Relevant to Cryogenic Laser Operation in Oxide Crystals Doped with Er 3+ Ions.
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Ryba-Romanowski W, Lisiecki R, Komar J, Macalik B, and Berkowski M
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Crystals of Gd
3 Al2.5 Ga2.5 O12 :Er3+ , (Lu0.3 Gd0.7 )2 SiO5 :Er3+ and LiNbO3 :Er3+ compounds differing in origin and the nature of their inherent structural disorder were crystalized. Optical absorption and luminescence spectra for transitions between the4 I15/2 and the4 I13/2 multiplets of Er3+ ions for the crystal samples were recorded versus temperatures in the region of 80-300 K. Gathered data were analyzed thoroughly providing the in-depth knowledge of the effects of temperature on intensities, wavelengths and bandwidths of Er3+ transitions. The information acquired together with the knowledge of significant structural dissimilarities of the host crystals chosen made it possible to propose an interpretation of the impact of a structural disorder in Er3+ -doped crystals on their spectroscopic properties, and to determine their lasing ability at cryogenic temperatures upon resonant (in-band) optical pumping.- Published
- 2023
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112. Enhanced Emission of Tellurite Glass Doped with Pr 3+ /Ho 3+ and Their Applications.
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Burtan-Gwizdala B, Reben M, Cisowski J, Lisiecki R, Jarząbek B, Alshehri A, Hussein KI, and Yousef ES
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The shielding and spectroscopic properties of Pr
+3 and Pr3+ /Ho3+ -codoped tellurite glass were investigated. The intensity parameters (Ω2 = 3.24-, Ω4 = 1.64-, Ω6 = 1.10 × 10-20 cm2 ) as well as the radiative lifetimes of3 F4 +5 S2 and5 I6 excited states of Ho3+ ions were equal to 301 μs and 3.0 μs, respectively. The former value appears to be much higher than that obtained from the lifetime measurement, indicating the presence of various energy transfer processes. The NIR spectrum of Pr3+ /Ho3+ -co-doped tellurite glass is dominated by strong Ho3+ :5 I6 emission at around 1200 nm, being the result of the energy transfer from Pr3+ to Ho3+ ions. The shielding effectiveness of the prepared glasses showed good performance against high-energy photons. These findings suggest that the prepared glasses could be used in laser technology such as photodynamic therapy (PDT) treatment procedures and as shielding for radiation protection.- Published
- 2023
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113. Examining the Spectroscopic and Thermographic Qualities of Er 3+ -doped Oxyfluoride Germanotellurite Glasses.
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Ryba-Romanowski W, Komar J, and Lisiecki R
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Novel ternary fluoro-germano-tellurite (GTS) glasses doped with Er
3+ ions with 0.5 mol% and 1.0 mol% were fabricated by a conventional melt and quenching method and investigated using methods of optical spectroscopy. The room-temperature absorption spectrum was recorded and analyzed to determine radiative transition rates, radiative lifetimes, and branching ratios of Er3+ luminescence. Decay curves of Er3+ luminesccence were recorded and analyzed. Temperature dependences of emission spectra and absorption spectra in the region from RT (room-temperature) up to 675 K were studied in detail. The contribution of competing radiative and nonradiative processes to the relaxation of luminescent levels of Er3+ was assessed. Absolute and relative sensitivity were established utilizing the comprehensive model based on thermally coupled2 H11/2 /4 S3/2 excited states of erbium. The high quantum efficiency of the first erbium-excited state and value of gain coefficient indicate that GTS:Er glass system can be considered as conceivable NIR (near infrared) laser material as well.- Published
- 2022
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114. Correction: Highly efficient green up-conversion emission from fluoroindate glass nanoparticles functionalized with a biocompatible polymer.
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Jimenez GL, Shrestha B, Porter T, Starzyk B, Lesniak M, Kuwik M, Kochanowicz M, Szumera M, Lisiecki R, and Dorosz D
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[This corrects the article DOI: 10.1039/D2RA03171J.]., (This journal is © The Royal Society of Chemistry.)
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- 2022
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115. Highly efficient green up-conversion emission from fluoroindate glass nanoparticles functionalized with a biocompatible polymer.
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Jimenez GL, Shrestha B, Porter T, Starzyk B, Lesniak M, Kuwik M, Kochanowicz M, Szumera M, Lisiecki R, and Dorosz D
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Up-conversion nanoparticles have garnered lots of attention due to their ability to transform low energy light (near-infrared) into high-energy (visible) light, enabling their potential use as remote visible light nano-transducers. However, their low efficiency restricts their full potential. To overcome this disadvantage, fluoroindate glasses (InF
3 ) doped at different molar concentrations of Yb3+ and Er3+ were obtained using the melting-quenching technique, reaching the highest green emission at 1.4Yb and 1.75Er (mol%), which corresponds to the4 S3/2 →4 I15/2 (540-552 nm) transition. The particles possess the amorphous nature of the glass and have a high thermostability, as corroborated by thermogravimetric assay. Furthermore, the spectral decay curve analysis showed efficient energy transfer as the rare-earth ions varied. This was corroborated with the absolute quantum yield (QY) obtained (85%) upon excitation at 385 nm with QYEr = 17% and QYYb = 68%. Additionally, InF3 -1.4Yb-1.75Er was milled and functionalized using poly(ethylene glycol) to impart biocompatibility, which is essential for biomedical applications. Such functionalization was verified using FTIR, TG/DSC, and XRD., Competing Interests: There are no conflicts to declare., (This journal is © The Royal Society of Chemistry.)- Published
- 2022
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116. The Structural and Optical Properties of 1,2,4-Triazolo[4,3- a ]pyridine-3-amine.
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Dymińska L, Hanuza J, Janczak J, Ptak M, and Lisiecki R
- Abstract
The structural and spectroscopic properties of a new triazolopyridine derivative (1,2,4-triazolo[4,3- a ]pyridin-3-amine) are described in this paper. Its FTIR spectrum was recorded in the 100-4000 cm
-1 range and its FT-Raman spectrum in the range 80-4000 cm-1 . The molecular structure and vibrational spectra were analyzed using the B3LYP/6-311G(2d,2p) approach and the GAUSSIAN 16W program. The assignment of the observed bands to the respective normal modes was proposed on the basis of PED calculations. XRD studies revealed that the studied compound crystallizes in the centrosymmetric monoclinic space group P 21 / n with eight molecules per unit cell. However, the asymmetric unit contains two 1,2,4-triazolo[4,3- a ]pyridin-3-amine molecules linked via N-H⋯N hydrogen bonds with a R2 2 (8) graph. The stability of the studied molecule was considered using NBO analysis. Electron absorption and the luminescence spectra were measured and discussed in terms of the calculated singlet, triplet, HOMO and LUMO electron energies. The Stokes shifts derived from the optical spectra were equal to 9410 cm-1 for the triazole ring and 7625 cm-1 for the pyridine ring.- Published
- 2022
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117. Laser Refrigeration by an Ytterbium-Doped NaYF 4 Microspinner.
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Ortiz-Rivero E, Prorok K, Martín IR, Lisiecki R, Haro-González P, Bednarkiewicz A, and Jaque D
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Thermal control of liquids with high (micrometric) spatial resolution is required for advanced research such as single molecule/cell studies (where temperature is a key factor) or for the development of advanced microfluidic devices (based on the creation of thermal gradients at the microscale). Local and remote heating of liquids is easily achieved by focusing a laser beam with wavelength adjusted to absorption bands of the liquid medium or of the embedded colloidal absorbers. The opposite effect, that is highly localized cooling, is much more difficult to achieve. It requires the use of a refrigerating micro-/nanoparticle which should overcome the intrinsic liquid heating. Remote monitoring of such localized cooling, typically of a few degrees, is even more challenging. In this work, a solution to both problems is provided. Remote cooling in D
2 O is achieved via anti-Stokes emission by using an optically driven ytterbium-doped NaYF4 microparticle. Simultaneously, the magnitude of cooling is determined by mechanical thermometry based on the analysis of the spinning dynamics of the same NaYF4 microparticle. The angular deceleration of the NaYF4 particle, caused by the cooling-induced increase of medium viscosity, reveals liquid refrigeration by over -6 K below ambient conditions., (© 2021 The Authors. Small published by Wiley-VCH GmbH.)- Published
- 2021
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118. Clinical Significance of Peritoneal Fluid Examination for Free Cancer Cells in Patients Qualified for Surgery for Gastric Cancer.
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Cieśla S, Lisiecki R, Ławnicka A, Kudliński B, Ostrowska P, Davì A, Veroux M, and Murawa D
- Abstract
Background: Peritoneal lavage cytology in patients with gastric cancer may correlate with an unfavorable prognosis. This study evaluated the presence of free cancer cells in the peritoneal lavage of a population of patients with gastric cancer and its correlation with the outcome of surgical treatment. Methods: One hundred patients diagnosed with gastric or gastrointestinal junction adenocarcinoma underwent surgery. In all patients, a cytological and immunohistochemical analysis of peritoneal lavage was performed. Based on the presence of free cancer cells (fcc) at the cytological and immunohistochemical examination of peritoneal lavage, patients undergoing surgery for gastric cancer were divided into two groups: fcc (+) and fcc (-). Results: A total of 100 patients, 37 women, and 63 men with a median age of 65 years were included in the study. In the entire study group, 16 (16%) patients were positive for the presence of free cancer cells (fcc +) at peritoneal lavage examination. However, in the group of patients who underwent gastrectomy, fcc (+) was found in 10 out of 77 (13%) patients. The presence of cancer cells in peritoneal lavage was a strong predictive factor in an unfavorable outcome after surgery, and 1-year and 2-year patient survival was 34 and 0% in fcc (+) patients and 79 and 59% in fcc (-), respectively. Moreover, the presence of free cancer cells was associated with a five-fold increased risk of death within 2 years after surgery. When analyzing the group of patients undergoing R0/R1 surgery, this difference was even more significant ( p < 0.0001). Conclusions: The presence of free cancer cells in peritoneal lavage may significantly affect the outcome of patients with gastric cancer. Radical surgery in patients with free cancer cells in the peritoneal lavage did not result in a survival advantage. Identification of free cancer cells could help for a better stratification of gastric cancer patients, identifying those patients who could better benefit from a radical surgical treatment, finally improving long-term survival., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2021 Cieśla, Lisiecki, Ławnicka, Kudliński, Ostrowska, Davì, Veroux and Murawa.)
- Published
- 2021
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119. Broadband Near-Infrared Luminescence in Lead Germanate Glass Triply Doped with Yb 3+ /Er 3+ /Tm 3 .
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Pisarski WA, Pisarska J, Lisiecki R, and Ryba-Romanowski W
- Abstract
This paper deals with broadband near-infrared luminescence properties of lead germanate glass triply doped with Yb
3+ /Er3+ /Tm3+ . Samples were excited at 800 nm and 975 nm. Their emission intensities and lifetimes depend significantly on Er3+ and Tm3+ concentrations. For samples excited at 800 nm, broadband emissions corresponding to the overlapped3 H4 →3 F4 (Tm3+ ) and4 I13/2 →4 I15/2 (Er3+ ) transitions centered at 1.45 µm and 1.5 µm was identified. Measurements of decay curves confirm reduction of3 H4 (Tm3+ ),2 F5/2 (Yb3+ ) and4 I13/2 (Er3+ ) luminescence lifetimes and the presence of energy-transfer processes. The maximal spectral bandwidth equal to 269 nm for the3 F4 →3 H6 transition of Tm3+ suggests that our glass co-doped with Yb3+ /Er3+ /Tm3+ is a good candidate for broadband near-infrared emission. The energy transfer from4 I13/2 (Er3+ ) to3 F4 (Tm3+ ) and cross-relaxation processes are responsible for the enhancement of broadband luminescence near 1.8 µm attributed to the3 F4 →3 H6 transition of thulium ions in lead germanate glass under excitation of Yb3+ ions at 975 nm.- Published
- 2021
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120. Exploring the Impact of Structure-Sensitivity Factors on Thermographic Properties of Dy 3+ -Doped Oxide Crystals.
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Lisiecki R, Komar J, Macalik B, Głowacki M, Berkowski M, and Ryba-Romanowski W
- Abstract
Optical absorption spectra and luminescence spectra were recorded as a function of temperature between 295 K and 800 K for single crystal samples of Gd
2 SiO5 :Dy3+ , Lu2 SiO5 :Dy3+ , LiNbO3 :Dy3+ , and Gd3 Ga3 Al2 O12 :Dy3+ fabricated by the Czochralski method and of YAl3 (BO3 )4 :Dy3+ fabricated by the top-seeded high temperature solution method. A thermally induced change of fluorescence intensity ratio (FIR) between the4 I15/2 →6 H15/2 and4 F9/2 →6 H15/2 emission bands of Dy3+ was inferred from experimental data. It was found that relative thermal sensitivities SR at 350 K are higher for YAl3 (BO3 )4 :Dy3+ and Lu2 SiO5 :Dy3+ than those for the remaining systems studied. Based on detailed examination of the structural peculiarities of the crystals it was ascertained that the observed difference between thermosensitive features cannot be attributed directly to the dissimilarity of structural factors consisting of the geometry and symmetry of Dy3+ sites, the number of non-equivalent Dy3+ sites, and the host anisotropy. Instead, it was found that a meaningful correlation between relative thermal sensitivity SR and rates of radiative transitions of Dy3+ inferred from the Judd-Ofelt treatment exists. It was concluded that generalization based on the Judd-Ofelt parameters and luminescence branching ratio analysis may be useful during a preliminary assessment of thermosensitive properties of new phosphor materials.- Published
- 2021
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121. Phonon Sideband Analysis and Near-Infrared Emission in Heavy Metal Oxide Glasses.
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Pisarska J, Pisarski WA, Lisiecki R, and Ryba-Romanowski W
- Abstract
In this work, spectroscopic properties of europium and erbium ions in heavy metal oxide glasses have been studied. The phonon energy of the glass host was determined based on Eu
3+ excitation spectra measurements. Near-IR emission spectra at 1550 nm related to4 I13/2 →4 I15/2 transition of erbium in heavy metal glasses were examined with special regards to luminescence bandwidth and measured lifetime. In particular, correlation between phonon energy and the measured lifetime4 I13/2 (Er3+ ) was proposed. The luminescence lifetime for the4 I13/2 upper laser state of erbium decreases with increasing phonon energy in glass matrices. Completely different results were obtained glass samples with europium ions, where the5 D0 lifetime increases with increasing phonon energy. Our investigations suggest that the values of measured5 D0 lifetime equal to radiative lifetimes for all heavy metal oxide glasses.- Published
- 2020
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122. Synergy between NIR luminescence and thermal emission toward highly sensitive NIR operating emissive thermometry.
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Marciniak L, Trejgis K, Lisiecki R, and Bednarkiewicz A
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There are many figures of merit, which determine suitability of luminescent thermometers for practical applications. These include thermal sensitivity, thermal accuracy as well as ease and cost effectivness of technical implementation. A novel contactless emission thermometer is proposed, which takes advantage of the coexistence of photoluminescence from Nd
3+ doping ions and black body emission in transparent Nd3+ doped-oxyfluorotellurite glass host matrix. The opposite temperature dependent emission from these two phenomena, enables to achieve exceptionally high relative sensitivity SR = 8.2%/°C at 220 °C. This enables to develop new type of emissive noncontact temperature sensors.- Published
- 2020
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123. Spectroscopic and structural investigations of blue afwillite from Ma'ale Adummim locality, Palestinian Autonomy.
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Juroszek R, Czaja M, Lisiecki R, Krüger B, Hachuła B, and Galuskina I
- Abstract
Until now, only the colourless crystals of mineral afwillite, Ca
3 (HSiO4 )2 ·2H2 O, were known from several localities around the world. Present work focuses on blue afwillite counterparts from the Ma'ale Adummim locality in Palestine. Using the wide spectrum of analytical methods we attempted to identify the causes of this unusual colour. Structural investigation confirms the presence of two tetrahedral SiO3 OH units connected by hydrogen bonds. The Raman spectrum of afwillite, obtained for the first time, shows the increased number of bands in the range of 785-970 cm-1 , whose assignation was correlated with the presence of two different kinds of structural units: (SiO3 OH)3- and its deprotonated counterpart (SiO4 )4- . The heating process at 250 °C, in addition to the colour changes from blue to pastel green, shows the intensity reduction and disappearing of some Raman bands attributed mainly to SiO3 OH units. The IR investigation confirms also the presence of that unit and provides information that the position and designation of infrared bands above ∼2300 cm-1 is related to the strength of hydrogen bonds within the structure. The stretching and bending OH vibrations of afwillite sample show the partial shift to the lower spectral frequencies after the H/D isotopic exchange in OH or H2 O groups. Based on the results of the electron absorption and luminescence analyses it has been proposed that the blue colour of afwillite is caused by hole oxygen defect, most probably SiO3 - ., (Copyright © 2019 The Authors. Published by Elsevier B.V. All rights reserved.)- Published
- 2020
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124. Yield of staging laparoscopy in gastric cancer is influenced by Laurén histologic subtype.
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Rawicz-Pruszyński K, Mielko J, Pudło K, Lisiecki R, Skoczylas T, Murawa D, and Polkowski WP
- Subjects
- Adult, Aged, Aged, 80 and over, Female, Follow-Up Studies, Humans, Male, Middle Aged, Neoplasm Staging, Prospective Studies, Adenocarcinoma pathology, Ascites pathology, Laparoscopy methods, Peritoneal Neoplasms secondary, Stomach Neoplasms pathology
- Abstract
Background: Staging laparoscopy (SL) with cytologic lavage is a useful staging procedure that allows tailoring the treatment of advanced gastric cancer (GC). The current study aimed to evaluate the total yield of SL in patients with various Laurén histo-types of GC, before planned neoadjuvant chemotherapy and gastrectomy., Methods: After exclusion of distant metastatic disease on imaging modalities, 173 patients with primary advanced gastric adenocarcinoma who underwent SL between August 2016 and September 2018, were eligible for the analysis. Patients sex, age, Lauren histo-type, tumor location, grade, cT, and cN were assessed in bivariate analysis. Multivariable logistic regression analysis was used to identify independent factors associated with peritoneal metastases., Results: Peritoneal metastases, ascites, and positive cytology were found in 39 (22.5%), 17 (9.8%) and 38 (22%) patients, respectively. The total yield of the SL in the current study was 36.4%. Multivariable logistic regression analysis revealed that serosal involvement (cT4) and diffuse histo-type were independent predictors of peritoneal metastases (OR, 15; 95% CI, 1.9-119, P = .02 and OR, 2.4; 95% CI, 1.2-4.6, P = .01, respectively)., Conclusions: Although cT4 and diffuse tumors show the highest association with peritoneal metastases, SL is a valuable diagnostic procedure in all advanced GC patients., (© 2019 Wiley Periodicals, Inc.)
- Published
- 2019
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125. Spectroscopic investigation and DFT modelling studies of Eu 3+ complex with 1-(2,6-dihydroxyphenyl)ethanone.
- Author
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Hanuza J, Ptak M, Lisiecki R, Kwocz A, Kucharska E, Ryba-Romanowski W, Mączka M, Hermanowicz K, and Macalik L
- Abstract
Eu
3+ complex with 1-(2,6-dihydroxyphenyl)ethanone in the solid state has been synthesized and characterized by elemental analysis, UV-visible, FT-IR and FT-Raman spectroscopies, powder X-ray diffraction, electron emission under femtosecond laser excitation. The stoichiometry and the formula of the studied complex have been proposed. Its physicochemical properties have been analyzed in terms of the structure and DFT calculations performed for the ligand. The luminescence and dynamics of the excited states depopulation have been studied using femtosecond laser excitation. Spectral and energetic transformation of femtosecond light impulses has been studied and possibility of the energy transfer between the ligand and the Eu3+ electron levels has been analyzed., (Copyright © 2018 Elsevier B.V. All rights reserved.)- Published
- 2018
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126. DFT study of electron absorption and emission spectra of pyramidal LnPc(OAc) complexes of some lanthanide ions in the solid state.
- Author
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Hanuza J, Godlewska P, Lisiecki R, Ryba-Romanowski W, Kadłubański P, Lorenc J, Łukowiak A, Macalik L, Gerasymchuk Y, and Legendziewicz J
- Abstract
The electron absorption and emission spectra were measured for the pyramidal LnPc(OAc) complexes in the solid state and co-doped in silica glass, where Ln=Er, Eu and Ho. The theoretical electron spectra were determined from the quantum chemical DFT calculation using four approximations CAM-B3LYP/LANL2DZ, CAM-B3LYP/CC-PVDZ, B3LYP/LANL2DZ and B3LYP/CC-PVDZ. It was shown that the best agreement between the calculated and experimental structural parameters and spectroscopic data was reached for the CAM-B3LYP/LANL2DZ model. The emission spectra were measured using the excitations both in the ligand and lanthanide absorption ranges. The possibility of energy transfer between the phthalocyanine ligand and excited states of lanthanide ions was discussed. It was shown that the back energy transfer from metal states to phthalocyanine state is responsible for the observed emission of the studied complexes both in the polycrystalline state and silica glass., (Copyright © 2018. Published by Elsevier B.V.)
- Published
- 2018
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127. Prognostic significance, diagnosis and treatment in patients with gastric cancer and positive peritoneal washings. A review of the literature.
- Author
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Lisiecki R, Kruszwicka M, Spychała A, and Murawa D
- Abstract
Peritoneal dissemination is a common consequence of a relapse following a radical surgical treatment of gastric cancer. The development of the disease in the peritoneum depends not only on its stage, but also on free cancer cells exfoliated from the tumor mass or from involved lymph nodes, and which are capable of being implanted in the peritoneum. According to the latest TNM (7 edition; 2010) classification, patients with free cancer cells in the peritoneal washings qualify for stage IV of the disease. Patients in whom free cancer cells were found during the operation - have a recurrence of gastric cancer - mainly in the peritoneum, and the majority of them die within two years of the diagnosis. To properly assess the prognosis, it is vital to determine the stage of cancer by additionally assessing the washings for the presence of free cancer cells before taking a therapeutic decision. This also allows identifying those patients who require different medical procedures to obtain the best treatment results possible. Medical literature describes various methods of examining peritoneal washings aimed at detecting free cancer cells. The methods apply different cancer cell detection rates, sensitivity and specificity in prediction of a peritoneal relapse. Oncological Departments performing the evaluation of the washings employ non-standard methods of treatment in this group of patients and the results presented are promising.
- Published
- 2017
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128. Analysis Of Risk Factors Of Positive Peritoneal Cytology In Patients Treated For Gastric Cancer--Preliminary Report.
- Author
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Lisiecki R, Spychała A, Pater K, and Murawa D
- Subjects
- Adenocarcinoma secondary, Adult, Aged, Aged, 80 and over, Female, Humans, Male, Middle Aged, Neoplasm Seeding, Neoplasm Staging, Peritoneal Lavage, Stomach Neoplasms pathology, Adenocarcinoma surgery, Neoplastic Cells, Circulating pathology, Peritoneal Cavity cytology, Peritoneal Neoplasms secondary, Stomach Neoplasms surgery
- Abstract
Unlabelled: Presence of free gastric cancer cells in the peritoneal cavity of patients who underwent surgical treatment for gastric cancer is a negative prognostic factor and caused rapid disease recurrence, manifested as peritoneal metastases. Positive peritoneal cytology despite lack of visible peritoneal metastases was regarded as M1 class in the TNM classification (7th edition) in 2010. The aim of the study was to analyze factors associated with positive peritoneal cytology and identify groups of patients in whom diagnostic laparoscopy plus peritoneal lavage in the diagnostic process could affect therapeutic decisions., Material and Methods: The study enrolled patients with gastric cancer who underwent surgical treatment at the Department of Surgery, Wielkopolskie Oncology Center in Poznań. During the laparotomy, after opening of the peritoneal cavity, 200 ml of physiological saline at 37 °C was administered in the tumor region. After this fluid was mixed, 100 ml of lavage fluid was collected. This fluid was subsequently spun many times to obtain sediment for cytology and immunohistochemistry investigation using anti-BerEp-4, CK 7/20, and B72.3. Results of peritoneal cytology were analyzed jointly with clinical factors--patient's age, sex and pathology factors--tumor invasion, involvement of lymph nodes, histological grade, histological type according to Lauren and localization of the cancer in the stomach., Results: Analysis of the peritoneal fluid for presence of free cancer cells was done in 51 patients. Positive peritoneal cytology was found in 12 (23.5%) patients. In the group of patients with positive cytology, all patients had T3/T4 tumors and all were found to have lymph node metastases, while G3 cancer was found in 83.3% of patients. In patients with positive cytology, diffuse gastric cancer according to Lauren predominated (9 of 12 patients, 75%), while in patients with negative cytology--intestinal type (20 of 39 patients, 51.2%). In the group of patients with positive histology, the whole stomach was involved by the cancer process in 7 of 12 patients (58.3%), while in the group with negative histology, in 29 of 39 patients the tumor was located in the gastric body and prepyloric part (74.4%)., Conclusions: Based on this study we can conclude that determinants of positive peritoneal cytology include: tumor stage T3/T4, N+, G3, cancer located in the whole stomach, diffuse histological type according to Lauren.
- Published
- 2015
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129. Prevalence and intensity of nematode parasites in Wisconsin ermine.
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Dubay S, Buchholz MJ, Lisiecki R, Huspeni T, Ginnett T, Haen L, and Borsdorf P
- Subjects
- Age Factors, Analysis of Variance, Animals, Body Composition, Chi-Square Distribution, Female, Linear Models, Male, Nematoda classification, Nematode Infections epidemiology, Nematode Infections parasitology, Prevalence, Sex Factors, Wisconsin epidemiology, Mustelidae parasitology, Nematoda growth & development, Nematode Infections veterinary
- Abstract
In the midwestern United States, ermine ( Mustela erminea ) are economically important because they are legally harvested for pelts. Information on parasites of ermine is lacking, and the effects that nematode parasites have on body condition of ermine hosts are unknown. We identified Skrjabingylus nasicola and Filaroides martis in ermine trapped from 2007 to 2013 from 6 counties in Wisconsin. Small mammals, commonly consumed by ermine, serve as paratenic hosts for both parasites. Our goal was to identify how age and sex of ermine, along with year, influence nematode parasitism. We also investigated how infection affected body condition for male and female ermine using body mass standardized by length as an index of body condition. We commonly found S. nasicola and F. martis in male and female ermine, but both prevalence and intensity of infection were higher for males. Relative to juveniles (<1 yr), adult (>1 yr) male ermine did not exhibit significantly higher intensity or prevalence of either parasite. We found that body condition was not compromised by infection for either sex, and intensity of S. nasicola and prevalence of F. martis were highest during the 2010-2011 trapping season. Of the 6 yr studied, precipitation was highest during the summer before the 2010-2011 season, and increased precipitation can cause increases in populations of gastropod intermediate hosts. We think that several distinct natural history components, namely, mating structure, diet, and metabolic rate, influence nematode parasitism in ermine.
- Published
- 2014
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130. Near-infrared ultrabroadband luminescence spectra properties of subvalent bismuth in CsI halide crystals.
- Author
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Su L, Zhao H, Li H, Zheng L, Ren G, Xu J, Ryba-Romanowski W, Lisiecki R, and Solarz P
- Abstract
We observed two ultrabroadband near-infrared (NIR) luminescence bands around 1.2 and 1.5 μm in as-grown bismuth-doped CsI halide crystals, without additional aftertreatment. Dependence of the NIR emission properties on the excitation wavelength and measurement temperature was studied. Two kinds of NIR active centers of subvalent bismuth and color centers were demonstrated to coexist in Bi:CsI crystal. The eye-safe 1.5 μm emission band with an FWHM of 140 nm and lifetime of 213 μs at room temperature makes Bi:CsI crystal promising in the applications of the ultrafast laser and ultrabroadband amplifier., (© 2011 Optical Society of America)
- Published
- 2011
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131. Rare earth-doped lead borate glasses and transparent glass-ceramics: structure-property relationship.
- Author
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Pisarski WA, Pisarska J, Mączka M, Lisiecki R, Grobelny Ł, Goryczka T, Dominiak-Dzik G, and Ryba-Romanowski W
- Subjects
- Luminescence, Spectrophotometry, Infrared, Spectroscopy, Near-Infrared, Spectrum Analysis, Raman, Structure-Activity Relationship, Temperature, Transition Elements chemistry, Borates chemistry, Ceramics chemistry, Lead chemistry, Metals, Rare Earth chemistry
- Abstract
Correlation between structure and optical properties of rare earth ions in lead borate glasses and glass-ceramics was evidenced by X-ray-diffraction, Raman, FT-IR and luminescence spectroscopy. The rare earths were limited to Eu(3+) and Er(3+) ions. The observed BO(3)↔BO(4) conversion strongly depends on the relative PbO/B(2)O(3) ratios in glass composition, giving important contribution to the luminescence intensities associated to (5)D(0)-(7)F(2) and (5)D(0)-(7)F(1) transitions of Eu(3+). The near-infrared luminescence and up-conversion spectra for Er(3+) ions in lead borate glasses before and after heat treatment were measured. The more intense and narrowing luminescence lines suggest partial incorporation of Er(3+) ions into the orthorhombic PbF(2) crystalline phase, which was identified using X-ray diffraction analysis., (Copyright © 2010 Elsevier B.V. All rights reserved.)
- Published
- 2011
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132. Effect of temperature on spectroscopic features relevant to laser performance of YVO4:Tm3+, GdVO4:Tm3+, and LuVO4:Tm3+ crystals.
- Author
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Lisiecki R, Solarz P, Dominiak-Dzik G, Ryba-Romanowski W, and Łukasiewicz T
- Abstract
Optical spectra and luminescence decay curves were measured for thulium-doped YVO(4), GdVO(4), and LuVO(4) single crystals as a function of temperature in the 300-670 K temperature region. In spite of structural similarity, the three systems studied display significantly different transition intensities and nonradiative relaxation rates. It was found, in particular, that the peak value of the pump band absorption intensity diminishes by about 30% for Tm:YVO(4) and Tm:GdVO(4), and the effective emission cross section for the laser transition of Tm(3+) diminishes by a factor of 2 roughly when temperature increases from 300 to 500 K. An unusually small quantum efficiency of the upper laser level in Tm:LuVO(4) has been derived from the analysis of luminescence decay curves.
- Published
- 2010
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133. Spectral characterization and laser performance of a mixed crystal Nd:(LuxY1-x)3Al5O12.
- Author
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Xu X, Cheng S, Meng J, Li D, Zhou D, Zheng L, Xu J, Ryba-Romanowski W, and Lisiecki R
- Abstract
An Nd-doped Lu(1.5)Y(1.5)Al(5)O(12) (Nd:LuYAG) crystal was obtained by Czochralski method. Absorption and emission spectra were recorded at low and room temperature. Continuous wave (CW) and passively Q-switched laser operations of Nd:LuYAG crystal were, to our knowledge, demonstrated for the first time. A CW output power of 1.67 W with slope efficiency of 39.8% was obtained. In the passively Q-switched operation, the shortest pulse width, largest pulse energy, and highest peak power were achieved to be 9.6 ns, 61.7µJ, and 6.4 kW, respectively, with Cr(4+):YAG crystals as the saturable absorbers.
- Published
- 2010
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134. Luminescence and phonon properties of nanocrystalline Bi2WO6:Eu3+ photocatalyst prepared from amorphous precursor.
- Author
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Maczka M, Fuentes AF, Hermanowicz K, Macalik L, Tomaszewski PE, Kepińiski L, and Lisiecki R
- Abstract
Bi2WO6:Eu3+ samples were prepared by mechanically activated metathesis reaction and subsequent annealing at different temperatures of the as-prepared precursor. X-ray, TEM, Raman, IR, diffuse reflectance and luminescence studies of the prepared samples are presented. It was found that variation of the particle size have significant impact on phonon and emission properties of this material. It was observed that intensity of some Raman and IR bands significantly decreases and the bandwidth of Raman, IR and Eu3+ emission lines significantly increases with decreasing particles size. Moreover, it was observed that intensity ratios I((5)D0-(7)F2)/I((5)D0-(7)F1) and I(5D0_(7)F0)/I((5)D0-(7)F1) increase with decreasing particle size. The observed changes were attributed to phonon confinement effect, decrease in the orthorhombic distortion of the unit cell and concentration increase of surface defects.
- Published
- 2010
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135. Estimation of low-temperature spectra behavior in Nd-doped Sc2SiO5 single crystal.
- Author
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Zheng L, Xu J, Su L, Li H, Wang Q, Ryba-Romanowski W, Lisiecki R, and Wu F
- Subjects
- Absorption, Lasers, Luminescent Measurements, Optical Phenomena, Spectrum Analysis, Neodymium chemistry, Silicates chemistry, Temperature
- Abstract
High optical quality Nd-doped Sc(2)SiO(5) crystal with size of diameter 27 mm x 60 mm was obtained by Czochralski method. An x-ray diffraction pattern of Nd:SSO crystal confirmed that the as-grown crystal was isostructual with the SSO crystal. Absorption and emission spectra were recorded at 10 K. The Judd-Ofelt theory was applied to obtain standard parameters Omega t(t=2,4,6) and the fitting result of experimental absorption line strengths, which provided the F3/24 radiative lifetime (tau(rad)) of 219 micros and the luminescence branching ratio beta of 0.57 for the (4)F(3/2)-(4)I(9/2) laser transition. The stimulated emission cross section of 1.04 x 10(-19) cm(2) at 1074 nm was calculated using the Füchtbauer-Ladenburg equation. The (4)F(3/2) luminescence lifetimes with 215 micros at 10 K and 198 micros at 300 K were determined from luminescence decay curves, indicating high quantum efficiency in the Nd:SSO crystal. All these results showed that Nd:SSO would be a promising gain media in solid-state lasers.
- Published
- 2009
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136. Effect of temperature on spectroscopic features relevant to laser performance of YVO4:Er(3+) and GdVO4:Er(3+) crystals.
- Author
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Lisiecki R, Solarz P, Dominiak-Dzik G, Ryba-Romanowski W, and Lukasiewicz T
- Abstract
Optical spectra and luminescence decay curves were measured for erbium-doped YVO(4) and GdVO(4) single crystals as a function of temperature in the 300 K-670 K temperature region. In spite of structural similarity the two systems studied display significantly different transition intensities and nonradiative relaxation rates. It was found in particular that the intensity of parasitic upconverted emission excited at 978 nm depends weakly on temperature for YVO(4):Er(3+), whereas it decreases monotonously with increasing temperature for GdVO(4):Er(3+) and becomes negligibly small at 670 K. It was concluded that GdVO(4):Er(3+) may be a promising laser active material operating at high thermal loading conditions encountered in high-power diode-pumped IR lasers.
- Published
- 2009
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137. Structural and optical properties of nano-sized K3Nd(PO4)2:Yb3+ orthophosphate.
- Author
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Mizer D, Macalik L, Tomaszewski PE, Lisiecki R, Godlewska P, Matraszek A, Szczygieł I, Zawadzki M, and Hanuza J
- Abstract
Nanocrystals of tripotassium neodymium bis-phosphate(V) doped with ytterbium ions, K3Nd(PO4)2: Yb3+, were synthesized by Pechini method. The obtained grains, having an average size of about 40 nm, were characterised by X-ray, electron microscopic, electron absorption, luminescence and IR studies. Moreover, fluorescence decay studies were carried out at room temperature. The energy transfer from the Nd3+ to Yb3+ was described and discussed. The results were compared to those of the K3Nd(PO4)2 bulk crystal.
- Published
- 2009
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138. Optical study of rare Earth-doped Gd3Ga5O12 nanocrystals obtained by a modified sol-gel method.
- Author
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Ryba-Romanowski W, Lipińska L, Lisiecki R, Rzepka A, and Pajaczkowska A
- Abstract
Spectroscopic features of Eu3+, Nd3+ and Er3+ in nanocrystalline samples of gallium gadolinium garnet prepared by a modified sol-gel method were investigated in order to assess the structural compatibility of the material with a single crystal counterpart. Emission spectra and decay curves of luminescent admixtures were recorded and analysed. Observed distribution of spectral line intensities and single exponential time dependence of luminescence decay curves indicate strongly that the static disorder in the neighbourhood of luminescent ions is not significant, hence structural peculiarities of the garnet lattice encountered in bulk crystals are maintained. It has been concluded that the method of preparation applied is able to furnish good structural quality GGG nanocrystals.
- Published
- 2009
- Full Text
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