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A digitális munkarendre való átállás a Covid-19 okozta járványügyi helyzetben gyors reakciót kívánt a pedagógusoktól. Sorra nyíltak a többezres csoportok a közösségi média különböző felületein, ahol aktív eszmecsere folyt a legjobbnak vélt megoldásokról. A felmérés központi kérdése az egyes digitális eszközök alkalmazásának népszerűsége, valamint ezek felhasználhatósága különböző pedagógiai célokra. Kitértünk arra is, hogy pedagógusok és diákok számára mennyire tűnt jól kezelhetőnek az adott eszköz, illetve, hogy a diákok hány százalékát sikerült elérni a digitális munkarend során. A kérdőíves felmérés 2020. március 18-tól fogad válaszokat, jelen tanulmányban az április 30-i kitöltöttségi adatokat dolgozzuk fel, mely 1071 pedagógus válaszát foglalja magában. A különböző megoldások értékelése eltérően alakult településtípusonként, oktatási profilonként, valamint az intézmény fenntartóját tekintve. A diákok elérésének mértéke szintén különbözik az egyes településtípusok mentén, valamint az oktatás egyes szintjein.The transition to a digital work schedule at schools required a rapid response from educators in the epidemiological situation caused by Covid-19. Several groups opened on various platforms of social media, where there was an active exchange of views on the solutions they considered the best. The main question of our survey is the popularity of the use of each digital tool and their usability for different pedagogical purposes. We also looked at how well the tool seemed to be manageable for educators and students, and what percentage of students were achieved during the digital work schedule. The questionnaire has been receiving responses from March 18, 2020. In this study, we process the completion data as of April 30, which includes the responses of 1,071 educators. The evaluation of the different solutions differs significantly (at level 95%) by types of settlement, educational profile and the maintainer of the institution. The extent of student achievement also depends significantly (at level 95%) on the type of settlement as well as on the levels of education.

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Rasvumite and "loparite-(Ce)" from the Mont Saint-Hilaire alkaline complex in Québec were re-examined using a variety of analytical techniques. Rasvumite crystals from a marble xenolith and tawite ("sodalite xenolith") entrained in nepheline syenite contain significant amounts of Rb and Cs (up to 7.2 and 2.6 wt.%, respectively). Our data indicate that these elements are more compatible with respect to rasvumite than sodalite, tainiolite, or perovskite-type phases. Cubo-octahedral crystals and penetration twins of "loparite-(Ce)" from the tawite comprise {100} growth sectors composed of loparite-(Ce) and {111} sectors composed of lueshite; the proportion of Na 0.5 Ce 0.5 TiO 3 and NaNbO 3 components varies by 15 mol.% between the sectors. In addition to the light rare-earth elements and Ti, the {100} sectors are enriched in K, Sr, Ba, Y, Th, U, Fe, Si and Zr with respect to the {111} sectors, which show higher levels of Na, Ca, Nb and Ta. Some elements (Ba, Th and U) exhibit a two-fold or greater difference in D between the sectors. Crystal-chemical analysis of the sector zoning indicates that higher-charged cations partition into surface protosites with fewer bonds satisfied (in agreement with Dowty's model). Among isovalent A-site cations, the larger partition into the {100} sectors. This observation is at variance with Dowty's predictions, but can be readily explained in terms of the relative differences in bond strength between large and small cations (estimated from their bond-valence parameters). The distribution of B-site cations is highly charge-dependent (but size-independent) and constrained mostly by heterovalent substitutions in the A site within a given sector. Comparison with the published data shows that the inter-sectorial distribution of cations in the perovskite structure is controlled not only by their charge, radius and involvement in coupled substitutions, but also by the chemistry of crystallization environment (e.g., availability of Nb). The implications of these data for the study of element partitioning in perovskites are discussed. The loparite-lueshite intergrowths and Rb-Cs-rich rasvumite in the tawite are interpreted to have crystallized in equilibrium with sodalite, aegirine and tainiolite from halogen-rich peralkaline magma. The tawite and its host nepheline syenite may have formed from cognate immiscible magmas, as proposed earlier by Piilonen, McDonald and Lalonde.

Bortolanite (IMA 2021–040a), ideally Ca2(Ca1.5Zr0.5)Na(NaCa)Ti(Si2O7)2(FO)F2, is a rinkite-group (seidozerite supergroup) TS-block mineral from Poços de Caldas massif, Minas Gerais, Brazil. Associated minerals are götzenite, nepheline, alkali feldspar, aegirine, natrolite, analcime, and manganoan pectolite. Bortolanite shows complex compositional zoning with götzenite and is visually indistinguishable from götzenite. Bortolanite is pale-yellow to brown and has a vitreous luster. Cleavage is perfect parallel to {100}. Mohs hardness is 5. Bortolanite fluoresces weak yellow under ultraviolet light (100–280 nm). Dcalc. = 3.195 g/cm3. Bortolanite is biaxial (+) with refractive indices (λ = 589.3 nm) α = 1.673(2), β = 1.677(2), γ = 1.690(2); 2Vmeas. = 56(2)°, 2Vcalc. = 58.4°. Chemical analysis by electron microprobe gave Nb2O5 1.07, HfO2 0.20, ZrO2 6.70, TiO2 9.94, SiO2 32.49, Gd2O3 0.12, Nd2O3 0.37, Ce2O3 1.25, La2O3 0.65, Y2O3 0.31, FeO 0.59, MnO 1.46, CaO 31.15, Na2O 8.36, F 6.95, O=F –2.93, sum 98.68 wt.%. The empirical formula based on 18 (O + F) apfu is (Ca1.88La0.03Ce0.06Nd0.02Gd0.01)Σ2[Ca1.56(Zr0.41Hf0.01Y0.02)Σ0.44]Σ2(Na0.85Ca0.15)Σ1(Na1.18Ca0.60Mn0.16Fe2+0.06)Σ2(Ti0.94Nb0.06)Σ1(Si4.07O14)(O1.24F0.76)Σ2F2, Z = 1. The simplified formula is Ca2(Ca,Zr)2Na(Na,Ca)2Ti(Si2O7)2(O,F)2F2. Bortolanite is triclinic, space group P, a 9.615(3), b 5.725(2), c 7.316(2) Å, α 89.91(1), β 101.14(1), γ 100.91(1)°, V 387.7(3) Å3. The crystal structure was refined to R1 = 3.19% on the basis of 2194 unique reflections [F > 4σ(F)] measured using a Bruker APEX II ULTRA three-circle diffractometer with a rotating-anode generator (MoKα), multilayer optics, and an APEX II 4K CCD detector. The crystal structure of bortolanite is a framework of TS (Titanium-Silicate) blocks [structure type B3(RG)], where the TS block consists of HOH sheets (H-heteropolyhedral, O-octahedral). The TS block exhibits linkage and stereochemistry typical for the rinkite group where Ti (+ Nb + Zr) = 1 apfu. The O sheet is composed of Ti-dominant MO(1) octahedra, [8]Na-dominant MO(2) polyhedra and (Na,Ca) MO(3) octahedra. In the H sheet in bortolanite, Si2O7 groups link to (Ca1.5Zr0.5) MH and Ca-dominant AP octahedra. Along a, TS blocks link directly through common edges of MH and AP polyhedra and common vertices of MH, AP, and Si polyhedra of the H sheets belonging to two TS blocks. The name bortolanite is after the locality: the Bortolan quarry in the Poços de Caldas massif, Brazil. Bortolanite is isostructural with three rinkite-group minerals: fogoite-(Y), hainite-(Y), and götzenite.