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Wyszukujesz frazę "78.55.-m" wg kryterium: Wszystkie pola


Tytuł:
Samarium-Doped Ceria Nanostructured Thin Films Grown on FTO Glass by Electrodepostion
Autorzy:
Živković, Lj.
Lair, V.
Lupan, O.
Cassir, M.
Ringuedé, A.
Powiązania:
https://bibliotekanauki.pl/articles/1503528.pdf
Data publikacji:
2011-08
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
81.15.Pq
68.55.Ln
61.46.Km
78.67.-n
Opis:
Electrical, optical or catalytic properties of ceria can be tuned via doping by rare earth elements. The innate properties of ceria-based materials can be further amplified by using nanostructured ceria. In this study, Sm-doped ceria (SDC) coatings were grown on the FTO glass substrate by means of cathodic deposition. Films were obtained from mixed $Sm^{3+}//Ce^{3+}$ aqueous nitrate solutions, applying -0.8V/(SCE) potential for 1 h. Selected conditions gave rise to adherent, homogeneous and well-covering nanostructured SDC thin films. EDX analysis showed that 0.8 and 1.5 mol% $Sm^{3+}$ led to 3.4 and 6.3 at.% Sm in the SDC films. XRD and Raman analysis confirmed the formation of cubic fluorite-type $CeO_{2}$. However, Sm-doping decreased the crystallite size of nanostructured ceria. The effect of annealing on SDC film was also studied. An improvement in crystallite quality was found with increasing temperature. Optical absorption properties were studied and the band gap value $(E_g)$ of 3.07 eV was determined for pure ceria. Sm-doped ceria exhibited a red shifting. The $E_g$ values were 2.97 and 2.81 eV, in due order.
Źródło:
Acta Physica Polonica A; 2011, 120, 2; 298-302
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
The Metalorganic Vapour Phase Epitaxy Growth of A^{III}B^{V} Heterostructures Observed by Reflection Anisotropy Spectroscopy
Autorzy:
Zíková, M.
Hospodková, A.
Pangrác, J.
Vyskočil, J.
Hulicius, E.
Oswald, J.
Komninou, P.
Kioseoglou, J.
Powiązania:
https://bibliotekanauki.pl/articles/1398563.pdf
Data publikacji:
2016-01
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
81.15.Gh
81.07.Ta
78.67.Hc
78.55.Cr
Opis:
Reflectance anisotropy spectroscopy is a useful technique used for in situ observation of the metalorganic vapour phase epitaxy growth, because it does not require vacuum in the reaction chamber. With this method we are able to observe the quantum dot growth, the incorporation of indium or antimony atoms in the layer or the monolayer growth of GaAs. We can also estimate the amount of InAs needed for the quantum dot formation, the time necessary for the quantum dot growth or reveal the unintended growth of InAs quantum dots from large dissolved InAs objects.
Źródło:
Acta Physica Polonica A; 2016, 129, 1a; A-75-A-78
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Effect of Lutetium Co-Doping on the Main Dosimetric Peak of YAP:Mn²⁺ Thermoluminescent Detectors
Autorzy:
Zhydachevskyy, Ya.
Głowacki, M.
Martynyuk, N.
Ubizskii, S.
Berkowski, M.
Suchocki, A.
Powiązania:
https://bibliotekanauki.pl/articles/1030950.pdf
Data publikacji:
2018-04
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
78.55.Hx
Opis:
An effect of lutetium co-doping on photoluminescent and thermoluminescent properties of the Mn²⁺-doped (Lu-Y)AP crystals (with Lu content from 0 to 20% with respect to Y) grown by the Czochralski technique has been studied. It was found that the maximum of the thermoluminescent peak at 200°C is shifted towards higher temperatures at Lu content more than 5%. At the same time the position of the second thermoluminescent peak near 350°C remains unchanged. The observed changes in the thermoluminescent peak position are discussed in terms of the point defects of the material.
Źródło:
Acta Physica Polonica A; 2018, 133, 4; 973-976
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Photoluminescence and thermoluminescence of the oxygen-deficient YAG, YAP, and YAM phosphors
Autorzy:
Zhydachevskyy, Ya.
Kamińska, I.
Glowacki, M.
Kilian, A.
Ubizskii, S.
Bilski, P.
Berkowski, M.
Fronc, K.
Elbaum, D.
Suchocki, A.
Powiązania:
https://bibliotekanauki.pl/articles/1052780.pdf
Data publikacji:
2018-04
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
78.55.Hx
Opis:
Photoluminescence and thermoluminescence of the oxygen-deficient Y₃Al₅O₁₂ (YAG), YAlO₃ (YAP) and Y₄Al₂O₉ (YAM) ceramics has been studied. Corresponding ceramic samples prepared by the same way however in oxidizing conditions (in air) were studied for comparison. The observed luminescent properties of the materials are related to the F-type centers created on the basis of oxygen vacancies, antisite (Y_{Al}) defects and uncontrolled Tb³⁺ impurity ions.
Źródło:
Acta Physica Polonica A; 2018, 133, 4; 977-980
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Photoluminescence Study of GaN
Autorzy:
Zhang, X.
Kung, P.
Saxler, A.
Walker, D.
Wang, Τ.
Razeghi, M.
Powiązania:
https://bibliotekanauki.pl/articles/1933686.pdf
Data publikacji:
1995-10
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
78.66.-w
71.55.Eq
68.55.-a
Opis:
Photoluminescence study of undoped, doped GaN grown on (00.1), (11.0), (01.2)Al$\text{}_{2}$O$\text{}_{3}$ (100), (111)Si, and (00.1)6H-SiC substrates have been conducted. Strong bandedge emissions from all undoped samples and dopant-related emissions from doped samples were observed. Deep-level yellow emission centered around 2.2 eV was not observed from undoped GaN grown on 6H-SiC substrate, undoped GaN with optimum Ga source flow and doped GaN. The experiment data strongly suggest that Ga vacancies are the origin this deep-level emission.
Źródło:
Acta Physica Polonica A; 1995, 88, 4; 601-606
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Effect of Trisodium Citrate on the Morphology and Luminescence Properties of Hydrothermally Synthesized YVO₄ Phosphor
Autorzy:
Zhang, Sa
Liang, Yan
Gao, Xiaoyong
Powiązania:
https://bibliotekanauki.pl/articles/1398668.pdf
Data publikacji:
2016-01
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
78.55.-m
61.05.cp
68.37.Hk
78.30.-j
Opis:
YVO₄ phosphors with different morphologies were synthesized by trisodium citrate (Na₃cit) surfactant-assisted hydrothermal process. Effects of molar ratio of $\text{cit}^{3-}$ to $Y^{3+}$ and pH value of reaction solution were intensively investigated on the morphologies, structures and luminescence properties of YVO₄ phosphor. The morphologies of the YVO₄ particles can be effectively controlled in strong acidic and strong alkaline environment by affecting the adsorption of $\text{cit}^{3-}$ on the (001) crystal plane of YVO₄. Strong acidic condition resulted into excessive adsorption of $\text{cit}^{3-}$ groups on the YVO₄ phosphor, which annihilated the superior luminescence of YVO₄ phosphors. On the contrary, strong alkaline condition does not result into the adsorption of $\text{cit}^{3-}$ groups. The synthesized YVO₄ phosphor without adsorption of $\text{cit}^{3-}$ groups showed superior luminescence even though the effective control of the morphology in alkaline condition is not so good as in strong acidic condition.
Źródło:
Acta Physica Polonica A; 2016, 129, 1; 79-83
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Hydrothermal Synthesis and Microstructural, Optical Properties Characterization of $YVO_4$ Phosphor Powder
Autorzy:
Zhang, S.
Liang, Y.
Gao, X.
Liu, H.
Powiązania:
https://bibliotekanauki.pl/articles/1207386.pdf
Data publikacji:
2014-01
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
78.55.-m
42.70.Hj
78.67.-n
Opis:
The phonon energy of $YVO_4$ crystal is lower than other usual compounds of salt. So it is suitable as host material for down-conversion materials. Hydrothermal method was adopted to synthesize $YVO_4$ phosphor powder with the use of yttrium oxide and sodium vanadate as raw material. The change in the relative integral intensity of the (200) and (112) diffraction peaks indicates that macroscopic stress in the lattice obviously changes with the elevated hydrothermal reaction temperature. The $YVO_4$ phosphor powder synthesized involves a certain agglomeration of small particles. The phonon vibration in the $YVO_4$ originates mainly from the internal vibrations in the vanadium-oxygen tetrahedron, in addition to the Y-O and O-H vibrations. Due to a low phonon energy of only $2.8188 × 10^{-21} J$, $YVO_4$ helps to improve the down-conversion efficiency of rare-earth ions. A bandgap value of approximately 3.8 eV for the synthesized $YVO_4$ powders leads to good absorption properties in the ultraviolet region. Upon excitation by the 320 nm ultraviolet photon, the intrinsic emission of $YVO_4$ powders is annihilated, and a broadband emission of $VO_4^{3-}$ near 450 nm is observed at room temperature. The $YVO_4$ phosphor powder synthesized at 180C exhibits the maximum photoluminescence intensity because of its excellent crystallization.
Źródło:
Acta Physica Polonica A; 2014, 125, 1; 105-110
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Strain Relaxation in Thin Films of La$\text{}_{1.85}$Sr$\text{}_{0.15}$CuO$\text{}_{4}$ Grown by Pulsed Laser Deposition
Autorzy:
Zaytseva, I.
Cieplak, M. Z.
Abal'oshev, A.
Berkowski, M.
Domukhovski, V.
Paszkowicz, W.
Shalimov, A.
Powiązania:
https://bibliotekanauki.pl/articles/2047252.pdf
Data publikacji:
2007-01
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
68.55.-a
74.62.-c
74.72.Dn
74.78.Bz
74.25.Fy
Opis:
X-ray diffraction, resistivity, and susceptibility measurements are used to examine the effects of film thickness d (from 17 to 250 nm) on the structural and superconducting properties of La$\text{}_{1.85}$Sr$\text{}_{0.15}$CuO$\text{}_{4}$ films grown by pulsed laser deposition on SrLaAlO$\text{}_{4}$ substrates. For each d the film sgrow with a variable strain, ranging from a large compressive strain in the thinnest films to a negligible or tensile strain in thick films. Our results indicate that the tensile strain is not caused by the off-stoichiometric layer at the substrate-film interface. Instead, it may be caused by the extreme oxygen deficiency in some of the films.
Źródło:
Acta Physica Polonica A; 2007, 111, 1; 185-188
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Growth and Properties of ZnMnTe Nanowires
Autorzy:
Zaleszczyk, W.
Janik, E.
Presz, A.
Szuszkiewicz, W.
Morhange, J. F.
Dłużewski, P.
Kret, S.
Kirmse, H.
Neumann, W.
Dynowska, E.
Domagała, J. Z.
Caliebe, W.
Aleszkiewicz, M.
Pacuski, W.
Golnik, A.
Kossacki, P.
Baczewski, L. T.
Petroutchik, A.
Karczewski, G.
Wojtowicz, T.
Powiązania:
https://bibliotekanauki.pl/articles/2047697.pdf
Data publikacji:
2007-08
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
61.46.Df
68.65.La
78.55.Et
78.67.Bf
81.15.Hi
Opis:
Catalytically enhanced growth of ZnMnTe diluted magnetic semiconductor nanowires by molecular beam epitaxy is reported. The growth is based on the vapor-liquid-solid mechanism and was performed on (001) and (011)-oriented GaAs substrates from elemental sources. X-ray diffractometry, scanning and transmission electron microscopy, atomic force microscopy, photoluminescence spectroscopy, and Raman scattering were performed to determine the structure of nanowires, their chemical composition, and morphology. These studies revealed that the obtained ZnMnTe nanowires possess zinc-blende structure, have an average diameter of about 30 nm, typical length between 1 and 2μm and that Mn$\text{}^{2+}$ ions were incorporated into substitutional sites of the ZnTe crystal lattice.
Źródło:
Acta Physica Polonica A; 2007, 112, 2; 351-356
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Photoluminescence Properties of ZnO and ZnCdO Nanowires
Autorzy:
Zaleszczyk, W.
Fronc, K.
Aleszkiewicz, M.
Paszkowicz, W.
Wróbel, J.
Dłużewski, P.
Kret, S.
Klepka, M.
Kłopotowski, Ł.
Karczewski, G.
Wojtowicz, T.
Powiązania:
https://bibliotekanauki.pl/articles/2047698.pdf
Data publikacji:
2007-08
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
78.55.Et
78.67.Bf
81.05.Dz
81.07.Bc
Opis:
We report on the photoluminescence studies of ZnO and ZnCdO nanowires grown on SiO$\text{}_{2}$/Si substrates by low-pressure vapor phase synthesis. X-ray diffraction and transmission electron microscopy measurements show that the crystallographic structure of these ZnO and ZnCdO nanowires is of wurtzite-type with a high crystal perfection. Surface morphology of samples was determined by scanning electron microscopy and atomic force microscopy. The photoluminescence spectra of as-grown nanowires, nanowires extracted from the substrate and deposited onto Si wafer, and nanowires dispersed in ethanol by sonication were investigated at room temperature and compared to each other. The temperature dependence of the near band-gap photoluminescence emitted by the as-grown nanowires was also measured and analyzed.
Źródło:
Acta Physica Polonica A; 2007, 112, 2; 357-362
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Photoluminescence Properties of ZnO Nanowires Grown on Ni Substrate
Autorzy:
Zaleszczyk, W.
Fronc, K.
Przeździecka, E.
Janik, E.
Czapkiewicz, M.
Wróbel, J.
Paszkowicz, W.
Kłopotowski, Ł.
Karczewski, G.
Wojtowicz, T.
Presz, A.
Powiązania:
https://bibliotekanauki.pl/articles/1812028.pdf
Data publikacji:
2008-11
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
78.55.Et
78.67.Bf
81.05.Dz
81.07.Bc
Opis:
Photoluminescence studies of zinc oxide nanowires produced by a carbo-thermal method on a nickel foil substrate are reported. Two types of as-grown samples: the first - containing only buffer film, and the second - containing both zinc oxide nanowires and buffer film grown in the same technological process, were investigated by means of the temperature-dependent photoluminescence. X-ray diffraction measurements of buffer film show that it is polycrystalline and is composed from wurtzite-type ZnO (main phase) and includes minority phases: rock salt type (Ni,Zn)O and hexagonal C₃N₄. The shape of the apparently monocrystalline nanowires is characterized by hexagonal section matching with the expectations of the hexagonal ZnO structure. The presence of LO-phonon replicas in photoluminescence spectra for the second sample is used as an argument for confirmation that ZnO nanowires are single crystalline. The method of growth of ZnO nanowires on nickel oxide opens perspectives to produce $Zn_{1-x}Ni_{x}O$ diluted magnetic semiconductor nanowires.
Źródło:
Acta Physica Polonica A; 2008, 114, 5; 1451-1456
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Optical Absorption and Luminescence of $Gd_{3}Ga_{5}O_{12}:Cr,Mg$ Epitaxial Films
Autorzy:
Zakharko, Ya.
Syvorotka, I.
Luchechko, A.
Sugak, D.
Vakiv, M.
Powiązania:
https://bibliotekanauki.pl/articles/1550184.pdf
Data publikacji:
2010-01
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
61.72.sd
78.20.-e
78.55.Hx
Opis:
The optical absorption, emission spectra and luminescence decay kinetics under photoexcitation of $Gd_{3}Ga_{5}O_{12}$ (GGG) garnet epitaxial films doped with $Cr^{3+}$ ions and co-doped with $Cr^{3+}$ and $Mg^{2+}$ ions have been investigated. Luminescence of the GGG:Cr films due to $\text{}^{4}T_{2}$ → $\text{}^{4}A_{2}$ and $\text{}^{2}E$ → $\text{}^{4}A_{2}$ transitions in $Cr^{3+}$ ions have been observed. Increase of the activator ions concentration has an influence on the intensity and decay time of $Cr^{3+}$ ions photoluminescence. Introduction of the magnesium ions leads to partial transformation of chromium valence state $(Cr^{3+} \rightarrow Cr^{4+})$ and to the appearance of a broad absorption band with the maximum at 860 nm. The narrow lines with luminescence maxima at 704 and 706 nm have arisen in the highly doped GGG:Cr,Mg films.
Źródło:
Acta Physica Polonica A; 2010, 117, 1; 111-113
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Czochralski Growth and Properties of Scintillating Crystals
Autorzy:
Yoshikawa, A.
Chani, V.
Nikl, M.
Powiązania:
https://bibliotekanauki.pl/articles/1399452.pdf
Data publikacji:
2013-08
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
81.10.Fq
78.70.Ps
29.40.Mc
78.55.Hx
Opis:
The Czochralski method is one of the very few melt growth techniques that are industry friendly when considering the combination of quality, dimensions, and cost of the produced crystals suitable for their commercialization in scintillation detectors. This method is one of the oldest and most developed crystal growth processes regarding an adequate understanding the physical phenomena observed during solidification process and its practical expansion especially in the industrial scale production. It allows controllable formation of single-crystalline cylindrical ingots of various inorganic scintillation materials. The review summarizes recent progress on the Czochralski growth of a number of scintillation materials. The oxide crystals are mainly considered including the Ce and Pr-doped $RE_3Al_5O_{12}$, RE = Y, Lu, aluminum garnets and newly discovered ultraefficient Ce-doped $Gd_3(Ga,Al)_5O_{12}$ multicomponent garnet, high density $PbWO_4$ and $CdWO_4$ tungstates, Ce-doped $RE_2SiO_5$, RE = Y, Gd, Lu, oxyorthosilicates and $(Y,Lu)AlO_3$ aluminum perovskites and finally the classical $Bi_4Ge_3O_{12}$ scintillator. Additionally, the details of the growth of other practically important non-oxide crystals, namely the Ce and Eu-doped $LiCaAlF_6$ neutron and ultraefficient Ce-doped $LaBr_3$ scintillators, are discussed. The potential of novel micro-pulling down growth method is briefly described in the combinatorial search for new scintillator materials. Selected luminescence and scintillation characteristics including the spectra and decay kinetics, light yield and radiation resistance are also illustrated and overviewed.
Źródło:
Acta Physica Polonica A; 2013, 124, 2; 250-264
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
ZnO Nanorods on Nanofibrous ZnO Seed Layers by Hydrothermal Method and Their Annealing Effects
Autorzy:
Yim, K.
Jeon, S.
Kim, M.
Kim, S.
Nam, G.
Lee, D.
Kim, Jin
Kim, Jong
Leem, J.
Powiązania:
https://bibliotekanauki.pl/articles/1491348.pdf
Data publikacji:
2012-01
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
81.05.Dz
81.15.Lm
78.55.Et
Opis:
ZnO nanorods were grown by using the hydrothermal method on p-type Si (100) substrates with nanofibrous ZnO seed layers. Before the ZnO nanorods growth, nanofibrous ZnO seed layers were spin-coated onto the Si substrates. The structural and optical properties of ZnO nanorods were characterized by scanning electron microscopy, X-ray diffraction, and photoluminescence. The fibrous ZnO nanorods is possible due to the surface morphology of the nanofibrous ZnO seed layers. To investigate annealing effects of the ZnO nanorods, the post-annealing process was carried out at various temperatures ranging from 300 to 700C under argon conditions. The structural and optical properties of the ZnO nanorods were also affected by the post-annealing treatment.
Źródło:
Acta Physica Polonica A; 2012, 121, 1; 214-216
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Stokes Shift and Band Gap Bowing in $In_xGa_{1-x}N$ (0.060 ≤ x ≤ 0.105) Grown by Metalorganic Vapour Phase Epitaxy
Autorzy:
Yildiz, A.
Dagdelen, F.
Aydogdu, Y.
Acar, S.
Lisesivdin, S.
Kasap, M.
Bosi, M.
Powiązania:
https://bibliotekanauki.pl/articles/1813499.pdf
Data publikacji:
2008-02
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
73.61.-r
78.20.-e
78.40.Fy
78.55.-m
Opis:
We presented the results of electrical and optical studies of the properties of $In_xGa_{1-x}N$ epitaxial layers (0.060≤x≤0.105) grown by metalorganic vapour phase epitaxy. Resistivity and Hall effect measurements of the samples were carried out at room temperature. Optical properties of the samples were characterized by photoluminescence and optical absorption spectroscopy. The comparison between the photoluminescence and the optical absorption measurements gives the Stokes shift. We explained the observed Stokes shift in terms of Burstein-Moss effect. The band gap versus composition plot for $In_xGa_{1-x}N$ alloys is well fitted with a bowing parameter of≈3.6 eV.
Źródło:
Acta Physica Polonica A; 2008, 113, 2; 731-739
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł

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