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The effect of sintering temperature on the structural and spectroscopic (CL, PL, decay) properties was investigated using 2.5 mol% Sm3+ doped BaTa2O6 samples, which were fabricated by solid state reaction at temperatures of 1150, 1250, 1350, 1425 degrees C. In XRD analysis of Sm3+ doped BaTa2O6 samples, orthorhombic phase appeared at temperatures of 1150 and 1250 degrees C, later the impurity phases disappeared at 1350 degrees C where orthorhombic polymorph completely transformed into a tetragonal tungsten bronze (TTB) structure. SEM analysis revealed the increase of grain size of Sm3+ doped BaTa2O6 with increasing sintering temperature. PL emissions were observed due to (4)G(5/2) -> H-6(J) (J = 5/2, 7/2, 9/2, 11/2, 13/2) transitions of Sm3+ where the emissions increased with the effect of increasing temperature and reached maximum at 1425 degrees C. The increase of PL emissions can be attributed to the developing of the tetragonal phase crystallinity which led to the decrease of non-radiative centers. CL emission of the undoped sample sintered at 1425 degrees C was monitored by the broad blue peak at about 495 nm which is related with the intrinsic emission of BaTa2O6. CL emissions of the doped samples sintered between 1150 and 1425 degrees C showed the host emissions and characteristic emissions of Sm3+ corresponding to (4)G(5/2) -> H-6(5/2), (4)G(5/2) -> H-6(7/2), (4)G(5/2) -> H-6(9/2), (4)G(5/2) -> H-6(11/2) transitions. The Sm3+ concentration led to a decrease in the decay time and an increase in the energy transfer, while the sintering temperature effect showed a different process where the decay time and energy transfer slightly increased.

International audience; Tetragonal tungsten bronze (TTB) phases possess numerous important properties (ferroelectricity, multiferroicity, piezoelectricity, optical nonlinearity, electro-optics) that can be achieved by modifying their composition, in addition to their ability to grow as very anisotropic crystals. In this study, K-5.06(Ta0.57Nb0.43)(10.99)O-30 tetragonal tungsten bronze phase thin films were grown by a pulsed laser deposition technique on (001)SrTiO3 and R-plane sapphire substrates. The films grew according to two modes with respect to the substrate surface, that is, as vertical nanorods with the [001] direction perpendicular to the substrate surface and as horizontal nanorods with the [001] orientation parallel to the substrate surface and < 310 > out-of-plane direction. Both vertical and horizontal nanorods present epitaxial relationships with the substrates. Careful study of epitaxial relationships showed a complex growth on both substrates that can be described in the framework of domain matching epitaxy resulting in several antiphase domain formations for both kinds of nanorods. These particular configurations are due to a high degree of coincidence between cations (anions) of the film with those of the substrate. This study shows the ability of ferroelectric TTB phases to grow as one-dimensional objects with the possibility to tailor their polarization direction either normal to or parallel to the substrate surface.

International audience; Three solid solutions of Tetragonal Tungsten Bronze structure containing Li were prepared by solid state route starting from the parent compound Ba2NdFeNb4O15. These solid solutions involve Li insertion compensated by cationic removal. All cationic sites were involved to investigate their influence on the dielectric transitions observed in Ba2NdFeNb4O15, i.e. from relaxor (R) to ferroelectric (FE) and finally to paraelectric (PE). All solid solutions display the same pattern, which is an evolution from a relaxor to ferroelectric crossover, leading to a single transition (relaxor to paraelectric). This evolution is accompanied by a sudden increase of the ordering temperature (Tm). A focus on structure refinements shows the slight differences induced by the insertion of Li and points towards the role of anionic framework as responsible for the dielectric properties of these materials. This study completes the work performed on other cationic substitutions performed in the title material, and represents a new example of Li substituted TTB materials.

U Republici Hrvatskoj temeljem STOKIS-a (Službenog topografsko-kartografskog informacijskog sustava) izrađen je model podataka CROTIS (Hrvatski topografsko-informacijski sustav), a na temelju CROTIS-a 2.0 za područje cijele države Temeljna topografska baza (TTB). U radu se opisuje CROTIS koji je, zbog napretka tehnologije, potrebnih poboljšanja uslijed potreba korisnika ili promjena u prostoru i propusta kod izrade prethodnih inačica, do danas imao više inačica. Do sada je izrađeno više prijedloga poboljšanja cijelog modela podataka, ali i određenih tematskih cjelina. Prijedlog izmjena modela CROTIS odnosi se na tematske cjeline: Promet, Građevine, Hidrografiju i Temeljni paket. U ovom će se radu dati i prijedlog poboljšanja za tematsku cjelinu Pokrov i korištenje zemljišta., In the Republic of Croatia, based on the Official Topographic-Cartographic Information System STOKIS, a Croatian Topographic Information System CROTIS data model was developed. Based on CROTIS 2.0, a basic topographic database (BTB) was created for the entire country. The paper describes CROTIS, which has had several versions to date due to advances in technology, necessary improvements because of user needs or changes in space and omissions in the development of previous versions. So far, several suggestions for improvement have been made for the entire data model, as well as certain thematic units. The proposed changes to the CROTIS model refer to the thematic units Transport, Buildings, Hydrography and the basic package. In this paper, a proposal for improvement for the thematic unit of Land Cover and Land Use will be given.

The crystal structure with different cationic sites and the superiority of allowing doping make TTB (tetragonal tungsten bronze) structures very interesting in terms of exhibiting different physical properties. The new spectroscopic and structural results of MTa2O6:Eu3+ (M = Sr, Ba, Pb) phosphors were presented in the study. The incorporation of europium activator into the different cationic (Sr, Ba, Pb) tunnel structures of TTB crystal with TaO6 octahedral exhibited interesting structural and optical properties. The relationship between coordination number and CTB showed that the highly coordinated A and B sites of TTB crystal caused the CTB to shift to low energy or over 300 nm. The spectral properties of TTB-MTa2O6 :Eu3+ (M = Sr, Ba, Pb) phosphors were compared by determining the Judd-Ofelt (JO) intensity parameters from PL emission spectrum. The (decreasing trend of the Omega(2) parameter and asymmetry ratio is SrTa2O6:Eu3+ > BaTa2O6:Eu3+ > PbTa2O6:Eu3+, and the Eu-O bonds of PbTa2O6:Eu3+ compared to other matrices indicated a more ionic character and a relatively high symmetry environment around Eu3+. The deviation of the experimental (beta(exp)) and Judd-Ofelt (beta(cal)) branching ratios for transition D-5(0)-> F-7(2) are well below 10%, indicating good consistency. All the D-5(0) decay profiles of the phosphors are exponential, and slightly reductions occurred in the luminescence lifetimes for SrTa2O6:Eu3+ and BaTa2O6:Eu3+. XRD results of Eu3+ doped SrTa2O6 series of the high-temperature TTB polymorph reported in this study confirmed the single-phase up to 10 mol%. SEM examinations revealed the change of size and shape of SrTa2O6 samples depending on Eu3+ concentration. (C) 2022 Elsevier B.V. All rights reserved.

The versatile crystal structure of tetragonal tungsten bronzes (A12A24C4B10O30) can accommodate complex stoichiometries including cations in different valence states and vacant cation sites. Here, we report on the effect of thermally induced cation-vacancy disorder in the tetragonal tungsten bronze SrxBa1−xNb2O6 (SBNX). SBNX (x = 0.25, 0.33, 0.50, 0.61) ceramics, prepared by conventional solid-state synthesis, were annealed at varying temperatures and subsequently quenched to room temperature. The Curie temperature of all the SBNX materials increased with higher quenching temperatures, accompanied with ferroelectric hardening. The variation in thermal history also caused structural changes, specifically a contraction of the a lattice parameter and a minor elongation of the c parameter. These effects are discussed in relation to recent first principles calculations of the energy landscape of the cation-vacancy configurations and experimental evidence of thermally induced cation-vacancy disordering.

In 1992, the State Geodetic Administration started with the development of cartography in the Republic of Croatia. After making a certain number of studies, STOKIS (the Official Topographic-Cartographic Information System) was defined. Topographic and cartographic data models were then defined by STOKIS. According to the STOKIS guidelines, the Croatian topographic information system (CROTIS) was developed as a data model and on the basis of CROTIS, the Basic Topographic Database (TTB) was established. One thematic entity contained in CROTIS 2.0, and whose data is often used, is the object entity of Hydrography. This article will provide an insight into the need to expand/correct the TTB data model in relation to the underlying basic package and the object entity of Hydrography, all in line with international standards and the INSPIRE directive.

The versatile crystal structure of tetragonal tungsten bronzes (A12A24C4B10O30) can accommodate complex stoichiometries including cations in different valence states and vacant cation sites. Here, we report on the effect of thermally induced cation-vacancy disorder in the tetragonal tungsten bronze SrxBa1&minus, xNb2O6 (SBNX). SBNX (x = 0.25, 0.33, 0.50, 0.61) ceramics, prepared by conventional solid-state synthesis, were annealed at varying temperatures and subsequently quenched to room temperature. The Curie temperature of all the SBNX materials increased with higher quenching temperatures, accompanied with ferroelectric hardening. The variation in thermal history also caused structural changes, specifically a contraction of the a lattice parameter and a minor elongation of the c parameter. These effects are discussed in relation to recent first principles calculations of the energy landscape of the cation-vacancy configurations and experimental evidence of thermally induced cation-vacancy disordering.

The symposium ISPDS2 has taken place in Meknes (Morocco) in October, 2017. It has gathered specialists of various fields who presented their work in connection with the problematics of data storage. This conference volume contains 75 abstracts of communications presented at the meeting as invited conferences, talks, or posters. Various topics are covered, as carbon nanotubes, SWCN, Domain walls, piezoelectrics, anomalous diffusion, electron microscopy, spectral moments, SiGe, nanocrystals, magneto-caloric, electro-caloric, ferrite, spinels, perovskites, graphene, solar cells, colossal magnetoresistance (CMR)

Državna geodetska uprava započela je 1992. godine rad na Službenom topografsko- kartografskom informacijskom sustavu (STOKIS), kojim su definirani topografski i kartografski modeli podataka. Smjernicama iz STOKIS-a izrađen je Hrvatski topografsko-informacijski sustav (CROTIS) kao model podataka temeljem kojeg je u razdoblju od 2003. do 2010. uspostavljena Temeljna topografska baza (TTB). CROTIS 2.0 sadrži dvije vrlo važne tematske cjeline koje se najčešće upotrebljavaju, a to su Građevine i Promet. U članku će se dati uvid kako bi se trebao proširiti/ispraviti model podataka TTB-a. Svaka struka ili djelatnost ima svoje specifičnosti i potrebe, pa je stoga potrebno unaprijediti postojeći model CROTIS-a kako bi se podaci iz TTB-a mogli što bolje i korisnije upotrebljavati u drugim strukama (npr. za prostorno planiranje, u Hrvatskim autocestama i Hrvatskim cestama, Hrvatskim vodama, Hrvatskim šumama i sl.), a sve u skladu s međunarodnim standardima i direktivom INSPIRE.

Državna geodetska uprava započela je 1992. godine rad na Službenom topografsko-kartografskom informacijskom sustavu (STOKIS), kojim su definirani topografski i kartografski modeli podataka. Smjernicama iz STOKIS-a izrađen je Hrvatski topografsko-informacijski sustav (CROTIS) kao model podataka temeljem kojeg je u razdoblju od 2003. do 2010. uspostavljena Temeljna topografska baza (TTB). CROTIS 2.0 sadrži dvije vrlo važne tematske cjeline koje se najčešće upotrebljavaju, a to su Građevine i Promet. U članku će se dati uvid kako bi se trebao proširiti/ispraviti model podataka TTB-a. Svaka struka ili djelatnost ima svoje specifičnosti i potrebe, pa je stoga potrebno unaprijediti postojeći model CROTIS-a kako bi se podaci iz TTB-a mogli što bolje i korisnije upotrebljavati u drugim strukama (npr. za prostorno planiranje, u Hrvatskim autocestama i Hrvatskim cestama, Hrvatskim vodama, Hrvatskim šumama i sl.), a sve u skladu s međunarodnim standardima i direktivom INSPIRE., In 1992, the State Geodetic Administration started working on the Official Topographic Cartographic Information System (STOKIS), which defined the topographic and cartographic data model. The STOKIS guidelines produced a Croatian Topographic Information System (CROTIS) as a data model based on which the Basic Topographic Database (BTD), 2003-2010 was established. Two very important themes of CROTIS 2.0 that are most commonly used are Buildings and Traffic. The article will provide an insight into the need to expand/correct the BTD data model. Each profession or activity has its own specifics and needs, so it is necessary to improve the existing model of CROTIS in order to use the BTD data as useful and useful as possible in other sectors (e.g. for Spatial planning, Croatian Motorways and Croatian Roads, Croatian waters, Croatian forests, etc.), all in line with international standards and INSPIRE directive.

TEAM1 has taken place in Sete (France) on 4, 5, 6 july 2017. It has gathered a little less than 40 participants who presented communications on various fields of advanced materials, and on experimental facilities or experimental methods, that are briefly summarized in the present volume. Presented abstracts deal with fullerenes, graphene, thin films, oxides, ferroelectrics, pyroelectrics, piezoelectrics, superconductors, nanomaterials, photovoltaics, X-ray diffraction, electron diffraction, electron microscopy, electron holography, carbon nanotubes, nanorods, ZnO.

International audience; K−Ta−Nb−O tetragonal tungsten bronze phase was grown on (11̅02) Al2O3 (R-plane sapphire) by pulsed laser deposition. The microstructure, structure, and chemical composition of the deposit were studied by scanning electron microscopy, X-ray diffraction, energy-dispersive X-ray spectrometry, and transmission electron microscopy. The crystal structure was solved by precession electron diffraction as being tetragonal tungsten bronze-type structure with space group P4/mbm, refined cell parameters a = 12.537 ± 0.003 Å, c = 3.975 ± 0.001 Å, and composition K5.06(Ta0.57Nb0.43)10.99O30. The tetragonal potassium tantalum niobate growth follows two modes with respect to the substrate surface: (i) as single vertical right parallelepiped-shaped nanorods (50 to 100 nm wide and up to 1 μm in length) along the [001] direction and (ii) as in-plane attached crystals along the ⟨310⟩ direction. These two growth modes are understood as being governed by the plane termination of the substrate. This new phase is of potential interest due to the physical (dielectric, catalytic, etc.) properties evidenced for tetragonal tungsten bronze phases in numerous systems.

International audience; Various memory technologies have emerged throughout history. Today, the discovery of new technologies and new materials over the past two decades has helped to manufacture memory devices, less bulky, less expensive, consuming less energy, but always with a larger capacity and higher speed data transfer. The international symposium ISPDS-1 has gathered researchers working on various aspects related with the problem of data storage, as Ferroics and Multiferroics, Memory storage devices, Switching phenomena, Heterojunctions and semiconductors, Energy and environment, and miscellaneous aspects. These proceedings gather abstracts of recent works in the field, presented at the symposium.

Završetkom izrade temeljnih skupova podataka dovršen je posao izrade jednog dijela službenih prostornih podataka u Republici Hrvatskoj. Kako se prostor oko nas neprestano mijenja, DGU ima zadaću i zakonsku obvezu održavanja prostornih informacija, odnosno kontinuiranog osiguranja ažurnih podataka potrebnih različitim korisnicima. U ovom radu opisani su postupci ažuriranja trenutnih proizvoda Državne geodetske uprave, nastalih unutar Službenog topografsko kartografskog informacijskog sustava (STOKIS). Dan je pregled stanja topografskih karata i topografskih baza podataka razvijenijih zemalja svijeta i zemalja u neposrednom okruženju Republike Hrvatske. Također, prikazan je kratak povijesni razvoj topografskih karata u Republici Hrvatskoj, te područja njihove primjene. Opis ažuriranja podataka TK25 i TTB potkrijepljen je praktičnim primjerom na listu karte Klis.

International audience; By partial cationic and anionic substitutions in NaNbO3-SrNb2O6 and KNbO3-SrNb2O6 systems, two solid solutions have been obtained: Sr2−xNa1+xNb5O15−xFx and Sr2−xK1+xNb5O15−xFx. They crystallize in the tetragonal tungsten bronze (TTB) type structure, which is related to that of the perovskite. The replacement of oxygen by fluorine causes a decrease of the Curie temperature. A weak F-O substitution rate increases the compactness, which leads to higher dielectric constant with good piezoelectric and pyroelectric characteristics. A relatively higher F-O substitution rate induces aferroelectricrelaxorbehavior. Such relaxorferroelectricceramics with lead-free compositions can be of great interest for environment-friendly applications.

International audience; Tetragonal tungsten bronze (TTB) films have been synthesised on Pt(111)/TiO2/SiO2/Si substrates from Ba2LnFeNb4O15 ceramics (Ln = La, Nd, Eu) by RF magnetron sputtering. X-ray diffraction measurements evidenced the multi-oriented nature of films with some degrees of preferential orientation along (111). The dependence of the dielectric properties on temperature and frequency has been investigated. The dielectric properties of the films are similar to those of the bulk, i.e., ε ∼150 and σ ∼10−6 Ω−1 cm−1 at 1 MHz and room temperature. The films exhibit two dielectric anomalies which are attributed to Maxwell Wagner polarization mechanism and relaxor behaviour. Both anomalies are sensitive to post-annealing under oxygen atmosphere and their activation energies are similar Ea ∼0.30 eV. They are explained in terms of electrically heterogeneous contributions in the films.

SAŽETAK: Dovršenjem izrade temeljnih skupova prostornih podataka u završen je posao izrade jednoga dijela službenih prostornih podataka u Republici Hrvatskoj. Posao koji predstoji Državnoj geodetskoj upravi (DGU) u slijedećem razdoblju bazira se na uspostavi što učinkovitijeg sustava ažuriranja prostornih podataka, jer njihova vrijednost i važnost zbog neažurnosti iz dana u dan postaje sve manja. Prostorne informacije danas postaju dnevni proizvod kojim se služe, odnosno koji potražuje sve veći broj korisnika. Nekada su to bile karte u raznim mjerilima u analognom obliku dok su danas to prostorni podaci u digitalnom obliku koji se pomoću novih tehnoloških pomagala koriste na razne načine. Kako se prostor oko nas neprestano mijenja, DGU ima zadaću i zakonsku obavezu održavati prostorne informacije, te mora učiniti sve kako bi osigurala ažurne podatke koje potencijalni korisnici traže, naravno uz aktivnu komunikaciju sa njima. Stoga je 2009. godine DGU pokrenula projekt Specifikacije ažuriranja Temeljne topografske baze (TTB) i izrade ažuriranih listova Topografske karte u mjerilu 1:25000 (TK25). Navedenom Specifikacijom definirane su smjernice za održavanje TTB-a i izradu ažuriranih izdanja TK25 na način da se bitne promjene objekata prikupljaju neposredno nakon nastanka, a da se istovremeno ne naruši prava kartografska vrijednost cijelog skupa.

Kada se govori o pocecima razvoja civilnog društva na našim prostorima, moraju se spomenuti osamdesete godine koje su doprinijele razvoju civilnog društva kakvo danas poznajemo. To su bile godine obilježene bu&enjem ženskih, mirovnih i ekoloških prava, pokreta za ljudska prava i opcenito su doprinijele demokratizaciji društva. Tada nije bilo prostora za mlade gdje bi mogli potpuno slobodno govoriti i raditi ono što drže potrebnim i ispravnim. Koliko god se stvarao dojam slobode, toliko su se i postavljale granice kada bi se ta sloboda pokušala iskoristiti otvaranjem nekoga važnijeg pitanja. Ovo su neki od razloga zbog kojih se pojavljuju pioniri aktivizma na našem prostoru. Postavljanjem temelja civilnoga društva u osamdesetim su se godinama dogodili znacajni pomaci na polju demokratizacije društva. Veliku ulogu tada su odigrale inicijative poput TTB-a i kasnije udruge Svarun, Ženske grupe Trešnjevka te danas poznate Zelene akcije.

Aim. As the number of elderly people grows, so does the interest in their needs for various services. The interest comes from various sides: elderly – as direct beneficiaries ; service providers ; public and private financial sources for these services. The aim of this research was to determine the level of community and social service utilisation among elderly in five European countries. Methods. The analysis was based on filed interviews with 3545 persons older than 70 across eight districts in five European countries: Ireland, Finland, Sweden, Greece and Croatia. The interviews comprised a number of instruments addressing different aspects of health and service utilisation. Results. Results show variations of service utilisation depending on the type of service, as well, as depending on the district. The northern districts more frequently use the chiropodist’s service, get help with cooking and cleaning, have social visits, receive meals, attend the day care centers than the southern, while the southern districts use more frequently financial advices. The other difference can be found when looking at the helpers within a certain service – in the north it is dominantly home help, while in the south it is relatives. Conclusion. The community and social services are rather underused. Generally, the more intimate the service, the less used it was. Elderly in this sample have rather strong social network, relying mostly on neighbours, apart from relatives and friends. Utilisation of community and social services varies between as well as within countries.

International audience; The Sr2−xK1+xNb5O15−xFx (0⩽x⩽1) solid solution of tetragonal tungsten bronze (TTB)-type was characterized by both crystallographic and dielectric properties. For small values of x (0⩽x

Single crystals of Ba6Fe0.90Nb9.10O30 and K4(Fe1.56Nb6.44)O21.4, were grown from high temperature solution at 1380 °C and 1150 °C, respectively, by the spontaneous nucleation method. Single-crystal X-ray diffraction confirmed that Ba6Fe0.90Nb9.10O30 belonged to the tetragonal tungsten-bronze (TTB) structure, with the space group P4/mbm (No. 127) and the lattice parameters a = 12.5895(3) and c = 3.98910(10) A. In contrast, K4Fe1.56Nb6.44O21.4 did not crystallize in the TTB structure and had a orthorhombic lattice instead, of which the space group was Pnma (No. 62) and the lattice parameters were a = 6.5371(6), b = 3.8212(3), and c = 18.6967(16) A. Crystal structure analysis showed that the centers of the anion polyhedra in both crystals had distorted from the sites of the cations. The estimation from the empirical equations showed that Ba6Fe0.90Nb9.10O30 was ferroelectric below room temperature, whereas the ferroelectric transition temperature for K4Fe1.56Nb6.44O21.4 was as high as 820 °C. Preliminary magnetic characterization suggested that Ba6Fe0.90Nb9.10O30 was likely to be antiferromagnetic at low temperature, while K4Fe1.56Nb6.44O21.4 was probably paramagnetic down to 10 K.