october 8–13, 2017, sofia, bulgaria program and...international autumn school on fundamental and...

October 8–13, 2017, Sofia, BulgariaBulgarian Academy of Sciences

International Autumn School on Fundamental and Electron Crystallography (IASFEC)

PROGRAM and ABSTRACTS

INVITED LECTURERS

• Prof.JokeHadermann,UniversityofAntwerp,Belgium• Prof.MassimoNespolo,UniversityofLorraine,France• Prof.MoisAroyo,UniversityoftheBasqueCountry,Spain

ORGANIZING COMMITTEE

• Associateprof.DanielaKarashanova,PhD–InstituteofOpticalMaterialsandTechnologies,BAS–chair

• Associateprof.BogdanRanguelov,PhD–InstituteofPhysicalChemistry,BAS• Associateprof.MihailTarassov,PhD–InstituteofMineralogyandCrystallo­

graphy,BAS• Assoc.prof.DianaNihtianova,PhD–InstituteofMineralogyandCrystallography,

BAS• Prof.RosicaNicolova,PhD–InstituteofMineralogyandCrystallography,BAS• Prof.BorisShivachev,PhD–InstituteofMineralogyandCrystallography,BAS• Prof.DanielaKovacheva,PhD–InstituteofGeneralandInorganicChemistry,

BAS• Assoc.prof.VladislavKostov­Kytin,PhD–InstituteofMineralogyandCrystallo­

graphy,BAS• Assoc.prof.ZaraCherkezova–Zheleva,PhD–InstituteofCatalysis,BAS• BilianaGeorgieva,PhD–InstituteofOpticalMaterialsandTechnologies,BAS• MayaVelichkova,PhD–InstituteofGeneralandInorganicChemistry,BAS• PavelMarkov,PhD–InstituteofGeneralandInorganicChemistry,BAS• LubenMihaylov,PhD–FacultyofChemistryandPharmacy,SofiaUniversity

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International Autumn School on Fundamental and Electron Crystallography, 8–13 October 2017, Sofia, Bulgaria

SCIENTIFIC PROGRAM

Day 1: 08 October 2017, Sunday

morning Arrival,registrationandaccommodationLecturer:prof.MoisAroyo

13:30–18:00 • Basicmatrixalgebra(matrixmultiplication,calculationofdetermi­nantandtrace)

Day 2: 09 October 2017, Monday

8:45–9:00 OpeningoftheSchool(Dr.DanielaKarashanova)Lecturers:prof.MoisAroyo,prof.MassimoNespolo

9:00–11:00 • Introductiontogrouptheory:thenotionofsymmetryandsymmetrygroups.

• Latticesandunitcells.Crystallographicsymmetryintwodimensions11:00–11:30 Coffeebreak

11:30–13:30 • Crystallographicsymmetryinthreedimensions:Bravaislattices,pointgroups,holohedriesandmerohedries,pointgroups;Hermann­Mauguinsymbolsforpointgroups.

13:30–15:00 Lunch

15:00–16:30 • Latticeplanes,MillerindicesandBravais­Millerindices.Forms,zonesandzoneaxes.

• ChoiceofthezonestolookatinEDforthedifferentcrystalsystems.• Introductiontothestereographicprojectionandexercisesonthestereographicprojectiontobuildcrystallographicpointgroups.

16:30–17:00 Coffeebreak17:00–18:45 • Subgroupsofpointgroups19:00–20:00 Dinner

Day 3: 10 October 2017, Tuesday

Lecturers:prof.MassimoNespolo,prof.MoisAroyo

9:00–11:00 • Metrictensorandcrystallographiccalculations:normofavector,anglebetweenvectors,changeofbasis.

11:00–11:30 Coffeebreak

11:30–13:30 • Symmetryoperationswithascreworglidecomponent.• Frompointtospacegroups.

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International Autumn School on Fundamental and Electron Crystallography, 8–13 October 2017, Sofia, Bulgaria

13:30–15:00 Lunch

15:00–16:30 • Examplesandexercisesonspacegroupdiagrams.• Projectionsofspacegroupsandtheirtwo­dimensionalsymmetry.

16:30–17:00 Coffeebreak

17:00–18:45 • Group­subgrouprelations.Klassengleiche,translationengleiche,iso­morphicsubgroups.Changeofbasisfromgrouptosubgroup.Defini­tionandbasicfeaturesofparentanddaughterphases.

• Integral,zonalandserialdiffractionconditions.• Diffractionsymbolandpossiblespacegroupscorrespondingtoit.

19:00–20:00 Dinner

Day 4: 11 October 2017, Wednesday

Lecturers and guidance:Dr.DanielaKarashanova,Dr.DianaNihtianova,Dr.BogdanRanguelov,Dr.MihailTarassov

09:30 Workinggroupsatrotationalprinciple1/2day TransmissionElectronMicroscopy(TEM)laboratoryvisit

• basicsofTEM• samplepreparationforTEM• experimentalSAEDandCBEDpatternscaption

1/2day Scanningelectronmicroscopy(SEM)–laboratoryvisit• basicsofSEM• samplepreparationforSEM• ElectronBackScatteredDiffraction(EBSD)

11:00–11:3016:00–16:30

CoffeebreakandexchangeofgroupsCoffeebreakandPostersession

13:30–14:45 Lunch14:45–15:00 School’sphotoinfrontofthemainentrance15:00–17:00 Postersession19:00–20:00 Dinner

Day 5: 12 October 2017, Thursday

Lecturer:prof.JokeHadermann

9:30–11:00 • IndexingofanEDpattern.• Calculation/simulationofaSAEDpatternforagivencompound(fromcellparametersandzoneaxis).

• ReconstructionoftheunitcellfromSAEDalongdifferentzoneaxes.

11:00–11:30 Coffeebreak

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International Autumn School on Fundamental and Electron Crystallography, 8–13 October 2017, Sofia, Bulgaria

11:30–13:30 • ConnectionofthesymmetryinrealspacetothatoftheEDpattern.• AnalysisoftheinformationonecanobtainfromCBED.

13:30–15:00 Lunch

15:00–16:30 • DifferencesbetweenthesymmetryinformationfromSAED(additionofinversioncentre,can‘tdistinguishmor2)andCBED(candistin­guishallpointsymmetryelements).

• ExercisesonexperimentalSAEDandCBEDpatterns

16:30–17:00 Coffeebreak

17:00–18:30 • Fromsuperlattices(subcells)inEDtosublattices(supercells)inrealspace.

• DeterminationofpointgroupsandspacegroupsfromEDpatterns.

19:30–22:30 OfficialDinner

Day 6: 13 October 2017, Friday

Lecturer:prof.MassimoNespolo

9:30–11:00 • Domains(twins,antiphasedomains);effectoftwinningonthedif­fractionpattern.

• Calculationoftwinindex,obliquity,unitcellofthetwinlattice.• Splittingofreflectionsfollowingaphasetransitiontoalowerlatticesystem.

11:00–11:30 CoffeebreakLecturer:prof.JokeHadermann

11:30–13:30 • Effectofthepresenceofsymmetryoperationswithaglidecompo­nentonEDpatterns,effectofscrewaxes,Gjonnes­Moodielines

• DeterminationofspacegroupsfromEDpatterns

13:30–15:00 Lunch15:00–16:30 • Dynamicaleffectsofthemultiplediffractionsandtheireffectonthe

reflectionconditionsandexpectedequivalenceofreflections.• Partialreconstructionofthespacegroupsymmetryfromatomicreso­lutionimages(projectionofspacegroups,effectsofmisorientation).

16:30–17:00 Coffeebreak

17:00–18:30 • ShortintroductiononthepossibilitiesofextractingandusingthereflectionsonEDpatternsinaquantitativemannertosolvestructuresabinitioandtorefinestructures.

• Exercisesonthedeterminationofspacegroupfromelectrondiffrac­tionpatterns.

18:30–18:45 Concludingremarks(Dr.DanielaKarashanova)19:00–21:00 Farewelldinner

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International Autumn School on Fundamental and Electron Crystallography, 8–13 October 2017, Sofia, Bulgaria

Necessary background (assumed achieved by all participants):• Interactionofradiationwithmatter.• Elementaryphysicsofscatteringanddiffraction.Fouriertransform,atomic

scatteringfactorandstructurefactor.• Reciprocallattice.• Bragg‘slawandEwald‘ssphere.

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International Autumn School on Fundamental and Electron Crystallography, 8–13 October 2017, Sofia, Bulgaria

CONTENTS

X­Raydiffraction,hightemperatureMössbauerandRamanspectroscopystudiesofSr3–xCaxFe2TeO9(0≤x≤1)doubleperovskite...................................... 11Abdelhadi El Hachmi, B. Manoun, Y. Tamraoui and P. Lazor

EffectofRuonthemagneticpropertiesofNi50Mn38Sb12....................................... 12Akhilesh K. Patel, K. G. Suresh

Valorizationofwastefromthewoodindustry(sawdust)andtheiruseasadsorbentmaterial:physicochemicalcharacterization,modelingandoptimizationadsorptionusingResponseSurfaceMethodology(RSM)................. 15Asmaa Salamat, Adib Merieme, Abdelkbir Kenz, Mohammed Talbi, M’hamed Elkouali, Tarik Ainane

Effectofannealingtemperatureonthecrystallinestructure,growthbehaviourandpropertiesofAlnico­typethinfilms................................................ 16Delia Patroi, Yuri Nikitenko, Vladimir Zhaketov, Eugen Manta, Eros Alexandru Patroi, Mirela Maria Codescu

SurfaceelectromigrationofAuonGe(111)byLowEnergyElectronMicroscopy............................................................................................... 17Ali El Barraj, Stefano Curiotto, Fabien Cheynis, Pierre Müller, Frédéric Leroy

Detectionandselectivityofexhaustgasestunedbyhydrophobiczeolites............ 19J. Grand, F. Dubray, S. N. Talapaneni and S. Mintova

StructureoftwonewK2SnX(PO4)3(X=Cr,In)Langbeinite­typephases............ 21H. Bellefqih, A. Marchoud, R. Fakhreddine, N. Boudar, R. Tigha and A. Aatiq

StructuralanalysisofFe/Vsuperlatticeusingtransmissionelectronmicroscope(TEM).................................................................................................. 22Hasan Ali

ChloritefromElatsitePCD,asamineralvector..................................................... 26H. Georgieva, R. Nedialkov

StudiesaboutM400andM800steelsampleseriesusingneutrondiffractionmeasurements........................................................................................ 27Alexandru Iorga, Delia Patroi, Gizo Bokuchava, I.V. Papushkin, Eros-Alexandru Patroi, Eugen Manta, Florina Radulescu

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International Autumn School on Fundamental and Electron Crystallography, 8–13 October 2017, Sofia, Bulgaria

Scanningelectronmicroscopy:adirectmethodofidentifyingpollengrains........ 29I. Piroeva, S. Atanasova-Vladimirova

Mesoporousnanostructuredceria­titaniamixedoxidedopedwithcopperascatalystsforsustainableenvironmentalprotection:Effectofpreparationprocedure......................................................................................... 30I. Genova, G. Issa, R. Ivanova, J. Henych, M. Dimitrov, D. Kovacheva, V. Štengl, T. Tsoncheva

DifferencesinthecrystallizationbehavioroftheBa0.6Sr0.4Zn2Si2O7phaseinthepresenceofoxidesandnoblemetals................................................... 32L. Vladislavova, Ch. Thieme, Ch. Rüssel

NewinsightsintotheeffectofawashinwateronthepropertiesofNa3V2(PO4)2F3–yOy(0≤y≤2)materialsaspositiveelectrodesforNa­ionbatteries................................................................................................................... 33L. H. B. Nguyen, T. Broux, P. Sanz Camacho, T. Bamine, A. Iadecola, L. Bourgeois, E. Suard, D. Carlier, Ch. Masquelier and L. Croguennec

TridymitefromAlšarundertheSEM­EDSandXRDinvestigations–evidenceforsilicicvolcanism................................................................................. 38M. Lazarova, T. Sijakova-Ivanova, I. Boev and B. Boev

Investigationofthechemisorptionof3­aminopropylsilylgroupsonsilicagelusingspectroscopytechniques.......................................................................... 39Miha Bukleski

Pt(Cu)catalystformethanoloxidationpreparedbygalvanicreplacementonTiO2powdersupport.......................................................................................... 41N. Dimitrova, J. Georgieva, S. Sotiropoulos, Tz. Boiadjieva-Scherzer, E. Valova, S. Armyanov

Morphologicalcharacterizationoforganic­inorganichybridmaterials................. 43N. Velikova, Y. Ivanova, I. Spassova

StructureandmagneticpropertiesofSr3Co2Fe24O41............................................... 44P. Peneva, T. Koutzarova, S. Kolev, Ch. Ghelev, B. Vertruyen, R. Closset, R. Cloots and A. Zaleski

Microstructuralcharacterizationofblacktourmaline............................................. 45R. Angelov, B. Georgieva, L. Angelova and D. Karashanova

Goniometryin21­stcentury.Whynot?................................................................. 47S. Dencheva

Surfacemorphologyofwinecrystals..................................................................... 48S. Atanasova-Vladimirova, I. Piroeva

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International Autumn School on Fundamental and Electron Crystallography, 8–13 October 2017, Sofia, Bulgaria

In vitro bioactivegelatin/silvercontainingsol­gelglassescomposites:FTIRandSEManalysis.......................................................................................... 49L. Radev, O. Kersten, I. Michailova, T. Dimova, Diana Zaimova

ChemicalbondingandnonlinearopticalpropertiesofTeO2–Bi2O3–B2O3glasses................................................................................... 50T. Tasheva, V. Dimitrov

Canineseminalplasma–functionsandinteractionwithcapacitation................... 51D. Daskalova, T. Tsvetkov, K. Lazov, D. Gradinarska, M. Hristova, M. Ivanova

CrystallochemistryofM2+­hydroxysaltminerals.................................................... 52Z. Delcheva

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International Autumn School on Fundamental and Electron Crystallography, 8–13 October 2017, Sofia, Bulgaria

X-Ray diffraction, high temperature Mössbauer and Raman spectroscopy studies of Sr3–xCaxFe2TeO9 (0 ≤ x ≤ 1) double

perovskite

AbdelhadiElHachmi1,*,B.Manoun1,Y.Tamraoui1andP.Lazor2

1 Laboratoire des Sciences des Matériaux, des Milieux et de la modélisation (LS3M), FP Khouribga, Hay Ezzaitoune BP 145, Khouribga 25000, Université Hassan 1er, Morocco

2 Department of Earth Sciences, Uppsala University, SE-752 36, Uppsala, Sweden

*elhachmi.abdelhadi@gmail.com

Keywords:Doubleperovskite,Sr3–xCaxFe2TeO9,X­raydiffraction,Ramanspectroscopy.

DoubleperovskiteswithgeneralstoichiometryA2BB′O6(A=alkalineearths;B,B′=transitionmetals)havebeenthetopicofalargenumberofstudiesin the lastfewyears,since thediscoveryofcolossalmagnetoresistanceinSr2FeMoO6 [1] and Sr2FeReO6 [2] because this effect is of technologicalinterestforthedetectionofmagneticfieldsandinmagneticmemorydevices[3].Thesematerialsarehalf­metallicferromagnetswithTC’ssignificantlyaboveroomtemperature.

X­raydiffractionandRamanspectroscopystudiesofCasubstituteddoubleperovskitecompoundSr3–xCaxFe2TeO9with (0≤x≤1)were investigated.BothRietveldrefinementsandRamanstudiesatroomtemperatureshowedthatserieshaveatetragonalsymmetrywiths.g.I4/m.PhasetransitionsareobservedbyRaman spectroscopy from tetragonal to cubic structures as afunctionof temperature.For this series, the transitions showconsiderablechangesinthetemperaturedependenceofthemodes:AlltheRamanmodesshowalinearbehaviorwhentemperatureisincreased,thentheslopechangedramaticallyindicatingthesymmetrychangebetweenthetwosystemsen­counteredintheseries.Mössbauerstudiesrevealthepresenceofironinthe3+oxidationstate.Aparamagnetictoferromagnetictransitionisobservedwhenstrontiumissubstitutedbycalcium(forx=0andx=0.5thematerialsareparamagneticandwhenx=1,thecompositionbecamemagnetic).References[1] Kobayashi,K.­I.etal.(1998)Nature395,677.[2] Kim,T.H.etal.(1999)Appl.Phys.Lett.74,1737.[3] Ramirez,A.P.(1997)J.Phys.:Condens.Matter.9,8171.

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International Autumn School on Fundamental and Electron Crystallography, 8–13 October 2017, Sofia, Bulgaria

Effect of Ru on the magnetic properties of Ni50Mn38Sb12

AkhileshK.Patel,K.G.Suresh*

Department of Physics, Indian Institute of Technology Bombay, Mumbai-400076, India

*suresh@phy.iitb.ac.in

Abstract.We report on the structural,magnetic and transport propertiesofRudopedNi50Mn38Sb12Heusleralloy.Thechangesinthecriticaltemperatureswiththemagneticfieldareexamined.Apartfromsecondordermagneticphasetransi­tionat326K,afirstorderstructuraltransitionfromcubicaustenitetoorthorhom­bicmartensiteoccursat265K.Magnetocaloriceffectiscalculatedandthemag­neticentropychangein70kOeisfoundtobe12.3Jkg–1K–1.

1. IntroductionThemulti­functionalityofHeusleralloyslikemagnetocaloriceffect(MCE),shape memory effect, exchange bias, magnetoresistance, has paramountsignificance in condensedmatter physics. In particular,MCE in these al­loys is promising [1]. In recent years, numerousmagneticmaterials havebeeninvestigatedinsearchofpotentialmagneticrefrigerantmaterials[2].Though, the first ordermagnetic phase transitionmaterials are associatedwithlatentheatandthermalhysteresis,thesematerialsarefoundtoexhibitlarge change inmagnetic entropy (ΔSM) at the transition temperature [2].Recently,Ni­MnbasedHeusleralloysbecameverypromisingduetotheirfirstordertransitionnearroomtemperature,largeMCEandshapememoryeffect[3,4].InNi­MnbasedcompoundsNi­Mn­Sn,Ni­Mn­InandNi­Mn­Sbarepromising[5–8].Inthiswork,westudiedtheeffectofRusubstitutionforNiinNi50Mn38Sb12.

2. Experimetnal TechniquesPolycrystallineNi46Ru4Mn38Sb12 ispreparedbyarcmeltingtheconstituentelements of highpurity.The ingot ismelted several times to ensured thehomogeneity.MagnetizationismeasuredusingSQUID­VSM(QD,USA).X­raydiffractioniscarriedoutusingPANalytical.ImaginganddiffractionpatternwerecarriedoutbyFEG­TEM.

3. Results and discussionFig. 1(a) shows the temperature dependentmagnetization in 500Oe col­lectedusingzero­fieldcooling(ZFC),fieldcooledcooling(FCC)andfield–

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International Autumn School on Fundamental and Electron Crystallography, 8–13 October 2017, Sofia, Bulgaria

cooledwarming(FCW)modes.Therespectivetemperaturesofmartensitic,austeniteandferromagneticphasesarelabeled.Magnetizationisothermsatatemperatureintervalof3KaroundthemartensitictransitiontemperatureTM~265K,arerecorded(notshownhere).

Usingtheseisotherms,themagnetocaloriceffectofNi46Ru4Mn38Sb12isesti­matedusingtheformulagivenbelow.

(1)

Fig.1showstheroomtemperatureX­raydiffraction(XRD),whichcrystal­izeincubicwithFm–3mspacegroup.Fig.2(a)showstheHRTEMimage,

Fig. 1. RoomtemperatureX­raydiffractionofNi46Ru4Mn38Sb12

1

0

),(),(H

H HM dH

THTMHTS  

Fig. 2.(a)HRTEMimageofNi46Ru4Mn38Sb12(b)TEMdiffractionpatternofNi46Ru4Mn38Sb12

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International Autumn School on Fundamental and Electron Crystallography, 8–13 October 2017, Sofia, Bulgaria

whichshowscrystallinenature.Fig.2(b)showstheTEMimageofthesam­pleandcorrespondingplanesindexedbytheir(hkl)values,whichisshowedcubicstructureandconfirmedtheX­raydiffraction

4. ConclusionsInconclusion,adetailedstructuralandmagneticstudyofRudopedNi­Mn­SbbasedHeusleralloyiscarriedoutusingXRD,TEMandmagnetization.Apart fromsecondordermagneticphase transitionat326K,a firstorderstructuraltransitionfromcubicaustenitetoorthorhombicmartensiteoccursat 265K. Inparticular,MCEaroundmartensitic transition temperature isfoundtobeabout12.3Jkg–1K–1.

AcknowledgementAKPacknowledgesUGCforthefinancialsupportthroughJRF.

References[1] A.K.Nayaketal.,2009J.Phys.D:Appl.Phys.42 035009[2] Pecharskyetal.,1997Phys. Rev. Lett. 78 4494[3] UllakkoKetal.,1996Appl. Phys. Lett. 69 1966[4] PasqualeMetal.,2005Phys. Rev. B72 094435[5] KrenkeTetal.,2005Nature 4 450[6] BhobePAetal.,2007Appl. Phys. Lett. 91 242503[7] KhanMetal.,2007J. Appl. Phys. 101 053919[8] DuJetal.,2007J. Phys. D: Appl. Phys. 40 5523

Fig. 3.(a)TemperaturedependentmagnetizationofNi46Ru4Mn38Sb12intherageof5–400K.Therespectivetransitiontemperaturesarelabeled.(b)Thechangeinmagneticentropyasafunctionoftemperature

inafewrepresentativemagneticfields.

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International Autumn School on Fundamental and Electron Crystallography, 8–13 October 2017, Sofia, Bulgaria

Valorization of waste from the wood industry (sawdust) and their use as adsorbent material: physicochemical

characterization, modeling and optimization adsorption using Response Surface Methodology (RSM)

AsmaaSalamat1,AdibMerieme1,AbdelkbirKenz1,MohammedTalbi1,M’hamedElkouali1,TarikAinane1,2*

1 Laboratory of Analytical Chemistry and Physical Chemistry of Materials, Faculty of Sciences Ben Msik, University of Hassan II, BP 7955 Casablanca 20660, Morocco

2 Superior School of Technology – Khenifra (EST-Khenifra), University of Moulay Ismail, PB 170, Khenifra 54000 Morocco

Keywords:waste,woodindustry,sawdust,physicochemicalcharacterization,modeling, optimization,RSM.

Thepresentworkreportsonsimpleandeffectiveecofriendlyapproachforthevalorizationofsawdust(wastefromthewoodindustry)intheenviron­mentalapplicationasadsorbentbiomaterials.

Afterdetermination thephysicochemicalpropertiesof the tested sawdust:pH, conductivity, the biomaterial was characterized using various instru­mental techniques including scanningelectronmicroscope (SEM), energydispersive spectroscopy (EDS) and Fourier transformed infrared spectro­scopy(FTIR).

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International Autumn School on Fundamental and Electron Crystallography, 8–13 October 2017, Sofia, Bulgaria

Effect of annealing temperature on the crystalline structure, growth behaviour and properties

of Alnico-type thin films

DeliaPatroi1,YuriNikitenko2,VladimirZhaketov2,EugenManta1,ErosAlexandruPatroi1*,MirelaMariaCodescu1

1 National Institute for R&D in Electrical Engineering INCDIE ICPE-CA, 313 Splaiul Unirii, 030138, Bucharest, Romania

2 Joint Institute for Nuclear Research, Frank Laboratory of Neutron Physics, Dubna, Russia

*eros.patroi@icpe­ca.ro,eros.patroi@gmail.com

Keywords:Alnico,Thinfilms,Sputtering,Rare­Earthfree.

Thin films of nominal composition Fe44.7Al17.2Co22.3Ni12.7Cu3.1 (at%) havebeen prepared by DC magnetron sputtering from the same compositiontargetalloy,closetoAlnico5permanentmagnets.TheirstructurehasbeenstudiedbymeansofscanningelectronmicroscopyandX­raydiffractionandrevealsapartlyamorphousstateintheaspreparedsamples.

TheirmagneticpropertiesareweakerthanthoseofaclassicAlnicoperma­nentmagnetorthosepreviouslyreported.Thefilmswererapidannealedat1000°C, following twodifferentwaysof rapidcooling,similar toclassicAlnicopermanentmagnetsannealingprocedure,thenstructuralandmagnet­icpropertieschangeswereinvestigated.Perpendicularmagneticanisotropywasrevealedwhilethemorphologyisdevelopingfromthincontinuousfilmtoacrystallinenano­particulatefilm.

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International Autumn School on Fundamental and Electron Crystallography, 8–13 October 2017, Sofia, Bulgaria

Surface electromigration of Au on Ge(111) by Low Energy Electron Microscopy

AliElBarraj,StefanoCuriotto,FabienCheynis,PierreMüller,FrédéricLeroy

CINaM-CNRS UMR 7325, Campus de Luminy Case 913 13288 Marseille Cedex 9, France

Theprojectconsistsinstudyingelectromigrationprocesses[1]atsurfacesinmetal­semiconductorsystems[2,3].Inpresenceofanelectriccurrentpass­ingthroughasample,anelectromigrationforcemayapplyonsurfaceatomsresultinginaglobalmasstransfer.ThisforcecanbedescribedasF=Z*eE,whereZ* isaneffectivevalence,e istheelectronchargeandE istheappliedelectricfield.TheeffectivevalenceZ* takesintoaccountboththeelectro­static interactionbetweentheelectricfieldE andthesurfaceatomcharge(chargetransferwiththesubstrate)calledthedirectforceandthefrictionalforceresultingfromthetransferofmomentumfromthechargecarrierstosurfaceatoms(windforce)[4].

WehavefirststudiedtheelectromigrationofAuatomiclayersonGe(111)substrate.Theexperimentswereperformedin situ inaUltraHighVaccum(UHV) setupequippedwithaLowEnergyElectronMicroscope (ElmitecLEEM III microscope) [5]. The Ge(111) single crystals were cleaned inUHVandpreparedbyionbombardment(Ar)andhightemperatureanneal­ing(900°C).Thenapproximately0.5MLofAuisdepositedattheGe(111)surface.Upon640°CtheAulayerformsadilute1×1reconstructionwhereasitrearrangesintodense√3×√3­R30°reconstructeddomainsbelow.Wehavecharacterizedthedriftmotionof√3×√3­domainsonatomicallyflatterracesinducedbyadirectelectriccurrent(~106A.m–2).Thedomainsvelocityde­pendsonthetemperature(Jouleseffect)andelectriccurrent.Increasingthetemperaturebetween500–640°C,theAudomainsvelocityvariesapproxi­matelyfrom30to800nm.s–1.

In the following figurewe can see anArrhenius plot of theAu domainsvelocity.Theslopeshows tworegimesathighand lowtemperature.Thisresultindicatesthattwomaindifferentprocessesofelectromigrationoccur.However,thedriftvelocityisindependentonthedomainsizeshowingthattheelementaryprocessofmotion isdominated inbothcasesbya terracediffusionprocessratherthanperipherydiffusionorattachment­detachment.

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International Autumn School on Fundamental and Electron Crystallography, 8–13 October 2017, Sofia, Bulgaria

References[1] P.S.HoandT.kwok,Rep.Prog.Phys.52,301–348(1989).[2] H.YasunagaandA.Natori,Surf.Sci.Rep.15,205–280(1992).[3] T.Ichinokawaetal.Phys.Rev.B47(15)9654(1993).[4] C.Taoetal.,Science328,736–740(2010).[5] F.Cheynisetal.Rev.Sci.Instru.B85043705(2014).

Fig. 1.(a)LEEMsequenceof2imagesshowingAudomainsdrift.(b)Arrheniusplotofthedomainvelocity.

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International Autumn School on Fundamental and Electron Crystallography, 8–13 October 2017, Sofia, Bulgaria

Detection and selectivity of exhaust gases tuned by hydrophobic zeolites

J.Grand1*,F.Dubray,S.N.Talapaneni2andS.Mintova1

1 Laboratoire Catalyse et Spectrochimie, Normandie Université, ENSICAEN, CNRS, 6 boulevard Maréchal Juin, 14050 Caen, France

2 University of South Australia (UniSA) Mawson Lakes Campus, South Australia, SA 5095, Australia

*julien.grand@ensicaen.fr

NanosizedMFItypezeolitenanocrystalscontainingdifferentmetalatoms,either incorporated in theframework(W–MFI)orextra­framework(Sn–MFI)havebeenpreparedandassembledashomogeneousandstablefilms.Inaddition,pure­silicaMFI(Si–MFI)zeolitefilmswerepreparedandusedas reference samples. All zeolite nanocrystals were spin­coated on sili­conwafersviaamulti­stepdepositionusingapolymerbinderinordertoincreasethemechanicalstabilityof thefilms.TheobtainedzeolitefilmswereexposedtodifferentconcentrationsofCO,CO2,NOandNO2gases(1–100 ppm) in the presence ofwater (100 ppm). The influence of thelocalizationofthemetalsandthehydrophobicityontheirselectivityandsorptioncapacitytowardsexhaustgaseswasinvestigatedbyfollowingthesorptionbehaviorbyoperandoIRspectroscopy.The high sensitivity of bothSn­MFI andW­MFI films towards very lowconcentrationsofexhaustedgases,especiallyCO2andNO2,inthepresence

Fig. 1. Detection ofCO2with (a)W–MFIand(c)Sn–MFIfilmsandCOwith (b)W–MFI and (d) Sn–MFIfilms.

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International Autumn School on Fundamental and Electron Crystallography, 8–13 October 2017, Sofia, Bulgaria

ofwaterwasdemonstrated(1–3ppm). Interestingly, ithasbeenobservedthattheincorporationofmetalatomsinthezeoliteframework,W–MFIfilm,leadstoanincreasedsensibilityandsorptioncapacitytowardsCOandCO2,whencomparedwiththeextra­frameworkSn–MFIfilm(Fig.1).ThiscouldbeexplainedbythehigherhydrophobicityoftheW­MFImaterial.

AcknowledgementWeacknowledgethefinancialsupportfromTARGED.

References[1] S.N.Talapaneni,J.Grand,S.Thomas,H.A.Ahmed,S.Mintova,Materials and Design

2016,99,574.[2] J.Grand,S.N.Talapaneni,J.P.Gilson,S.Mintova,PatentWO2017068387A12017;J.

Grand,S.N.Talapaneni,A.Vicente,C.Fernandez,E.Dib,H.A.Aleksandrov,G.N.Vayssilov,R.Retoux,P.Boullay,J.P.Gilson,V.Valtchev,S.Mintova,Nature Mater.,accepted.

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International Autumn School on Fundamental and Electron Crystallography, 8–13 October 2017, Sofia, Bulgaria

Structure of two new K2SnX(PO4)3 (X = Cr, In) Langbeinite-type phases

H.Bellefqih*,A.Marchoud,R.Fakhreddine,N.Boudar,R.TighaandA.Aatiq

Département de Chimie, Laboratoire de Physico-Chimie des Matériaux Appliqués, Université Hassan II de Casablanca, Faculté des Sciences Ben M’Sik, Avenue Idriss

El harti, B.P. 7955, Casablanca, Morocco

*hajar.bellefqih@gmail.com

Keywords:langbeinitestructure;Rietveldrefinement;X­raydiffraction.

Structures of twoK2SnX(PO4)3 (X=Cr, In) phosphates, obtainedby con­ventionalsolidstatereactiontechniquesat950°C,weredeterminedatroomtemperaturefromX­raypowderdiffraction(XRD)usingtheRietveldanaly­sis. The twomaterials exhibit the Langbeinite­type structure (P213 spacegroup,Z=4).Cubicunit cellparametervaluesare:a=9.8741(1)Åanda = 10.0460(1)Å forK2SnCr(PO4)3 andK2SnIn(PO4)3 respectively. FinalRietveldrefinementsleadtoacceptablereliabilityfactors(e.g.,Rwp=9.1%;RB=5.2%forK2SnCr(PO4)3andRwp=8.1%;RB=5.1%forK2SnIn(PO4)3.LangbeiniteframeworksareprincipallybuiltofSn(X)O6octahedrasharingcornerswithPO4tetrahedra.Structuralrefinementsshowthatthetwocrys­tallographicallyindependentoctahedralsites(ofsymmetry3)haveamixedSn/X (B=Cr, In) population. The two potassium cations occupied largeisolatedcageswithintheframework.

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International Autumn School on Fundamental and Electron Crystallography, 8–13 October 2017, Sofia, Bulgaria

Structural analysis of Fe/V superlattice using transmission electron microscope (TEM)

HasanAli

Angström Laboratory, Upsala, Sweden

hasan.ali@angstrom.uu.se

Fe/Vmultilayershavebeenusedasamodel system to studyandexplorevariousfundamentalproblemsincondensedmatterphysics,forexamplethinfilmmagnetism[1].Insuchthinmetallicmultilayers,thephysicalpropertiesofthesystemstronglydependoncrystalqualityofthestructure.Thecrystalqualityinturnisinfluencedbylayerthicknessandstraininthesystem.Tostudytheeffectofthicknessandstrainoncrystalquality,Fe/Vmultilayerswere grownwith different layer thicknesses and subsequently the crystalstructureandstrainwasdeterminedbyusingdifferenttechniques.

Transmissionelectronmicroscope(TEM)wasappliedasastructuralcharac­terizationtooltodeterminethelayerstructureandstraininoneofthegrownsamples.ThesamplechosenforTEMcharacterizationwasaFe/Vsuperlat­tice(SL)withFe=4andV=28monolayers(ML)depositedonasinglecrystallineMgO(001)substrate.TheSLstartsandendswithVlayerandwascappedwithapalladium(Pd)layertoreducetheeffectsofoxidation.

Thesamplewaspreparedbyusingquadmagnetronsputteringsystem.Thesamplestagewasrotatedtoobtainahomogeneousdepositionacrossthesur­face.Thetemperatureofthesubstratewascontrolledwithin~1K.Thebasepressureofthegrowthchamberwas2.7×10–7Paandwasachievedusingthecombination of a turbo­molecular pump and aTi sublimation pump.Thetargetswere99.99%pureandtheArgaswasof99.9997%purity.

TEM sample was prepared in a cross­sectional geometry by mechanicalpolishing, dimple grinding and finally grazing incidence Ar ion milling.Scanningtransmissionelectronmicroscope(STEM),highresolutionTEM(HRTEM)andselectedareadiffraction(SAD)techniqueswereappliedtodeterminethestructureandmeasurethestraininthesystem.Fig.1showsahighangleannulardarkfield(HAAD)imageofthesample.Itcanbeseenthatthelayersareflatandnowavinessispresent.Fig.2showsaHRTEMimageof thesample.Due tocloseatomicnumbersofFeandV,noclearcontrastisseenbetweenthelayers.AlsoduetoatomicstepsattheMgOsub­

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International Autumn School on Fundamental and Electron Crystallography, 8–13 October 2017, Sofia, Bulgaria

strate,itisveryhardtoexactlymarktheinterfacesbetweenFeandV.ThelatticespacingsofFeandV,bothinplaneandoutofplane,weremeasuredusinglineprofiles.Thestraininthesystemwasthendeterminedusingtheformula

Fig. 1. HAADFimageofFe/V(4/28)SL

Fig. 2. HRTEMimageofFe/V(4/28)SL

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International Autumn School on Fundamental and Electron Crystallography, 8–13 October 2017, Sofia, Bulgaria

ThemeasuredvaluesofstrainaregiveninTable.1.Thesevaluescloselymatch to thevaluesmeasuredbyour collaboratorsusing an analysispre­sentedbyBirchetal.[2].

Fig.3showstheSADpatternofthesample.TheSLreflectionscanbeseenveryclearly.TheSLperiodwasmeasuredtobeabout4.54nmwhichagreesverywellwiththepreviouslymeasuredvaluesbyX­raytechniques.

Inconclusion,weuseTEMasastructuralcharacterizationtool tocloselyviewthelayeringandcrystalstructureofFe/V(4/28)SLdepositedonMgO(001)substrate.Wemeasurethevaluesoflatticeparameters,strainandsu­perlatticeperiodwhichcloselymatchtothepreviouslymeasuredvaluesbyX­raytechniquesandhenceverifyandstrengthenthoseresults.

Table. 1. Measured values of strain from Fig. 1

Fig. 3.SADpatternofFe/V(4/28)SLattheregionofMgO­filminterface

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References[1] B.Hjorvarsson, J.A.Dura,P. Isberg,T.Watanabe,T. J.Udovic,G.Andersson,C.

F.Majkrzak, Reversible Tuning of theMagnetic Exchange Coupling in Fe/V (001)SuperlatticesUsingHydrogen,Phys.Rev.Lett.79(5)(1997)901–904.

[2] J.Birch,J.­E.Sundgren,P.Fewster,Measurementofthelatticeparametersintheindi­viduallayersofsingle­crystalsuperlattices,JApplPhys78(11)(1995)6562.

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Geochemical characteristics and composition of chlorites from Elatsite PCD, Bulgaria

H.Georgieva*,R.Nedialkov

Sofia University “St. Kliment Ohridski”, Faculty of Geology and Geography

*hristiana.georgieva@abv.bg

The Elatsite porphyry copper deposit (PCD), part of the Apuseni­Banat­Timok­Srednogoriecopperbelt,isoneofthebiggestandwell­studiedPCDsinEurope.ItsoremineralizationisrelatedtotheUpperCretaceousmagma­tism.Asmallporphyriticintrusion(Q­monzodioritetoGranodiorite)elon­gatedinE­Wdirectionandmanyporphyriticdikesareintrudedintherocksof the basement (theVezhenVariscan granodiorite pluton and the varie­gatedPaleozoicgreenschistdegreeschists).Studiesontheoremineraliza­tionreveal5oremineralparageneses–thehydrothermalrockalterationsaredeterminedaspropylitic,hightemperatureK­silicatealteration,K­silicate­sericitic,Q­sericiticandquartz­adularia­carbonaticalteration.

Chlorites in Elatsite have been established through: a) propylitic altera­tion­withchlorite(Chl­1)replacingmagmaticbiotiteandamphiboles;b)K­silicate­sericitic alteration­withChl­2 replacing the hydrothermal blackmica(phlogopite);c)Q­sericiticandquartz­adularia­carbonaticalterationswhereChl­3participatesintheformationofnests(simultaneous)andvein­lets(subsequenttothealterations).

Studyingtheprocessofchloritizationisanimportantstepforthebetterun­derstandingand interpretationof thedistributionoforecomponentof thedeposit.After the electronmicroprobe andLA­IMS­MSanalysisof chlo­ritefromthedifferenttypesofalterationsisestablishedanunequaldistribu­tionoforeelementsinalteredminerals.Thereforethenextstepinthestudywillbetheapplicationofelectronmicroscopyasamethodtodeterminethemechanismofsubstitutionofminerals[1,2].

References[1] Eggleton, R. and Banfield, J.(1985) The alteration of granitic biotite to chlorite –

AmericanMineralogist,Vol.70,pp.902–910.[2] Yuguchi, T., Sasao, E., Ishibashi, M., Nishiyama, T. (2015) Hydrothermal chloriti­

zationprocesses frombiotite in theTokigranite,Central Japan:Temporalvariationsof thecompositionsofhydrothermalfluidsassociatedwithchloritization–AmericanMineralogist,Vol.100,pp.1134–1152.

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Studies about M400 and M800 steel sample series using neutron diffraction measurements

AlexandruIorga1*,DeliaPatroi1,GizoBokuchava2,I.V.Papushkin2,Eros­AlexandruPatroi1,

EugenManta1,FlorinaRadulescu1

1 INCDIE ICPE-CA, Bucharest, Romania 2 FLNP JINR, Dubna, Russia

*alexandru.iorga@icpe­ca.ro

Keywords:Neutrondiffraction,electricalsheets,magneticlosse.

The have been investigated structural changes in specimen seriesM400andM800byneutronTOFdiffractionmethod.Theexperimentswereper­formedonFourierstressdiffractometerFSDattheIBR­2fastpulsedre­actorinFLNPJINR(Dubna,Russia)[1,2].TheFSDdiffractometerwasspeciallydesignedforresidualstressstudiesinbulkindustrialcomponentsandnewadvancedmaterials.OnFSDaspecialpurposecorrelationtech­nique is used to achieve high resolution level of the diffractometer – acombinationofthefastFourierchopperfortheprimaryneutronbeamin­tensitymodulationandthereversetime­of­flight(RTOF)methodfordataacquisition[3,4].

DuringtheexperimentontheFSDdiffractometerinvestigatedsampleswereinstalledonHUBERgoniometerwithflatsideperpendiculartotheincidentneutron beam limited by diaphragmof 10×24mm. In thisway it is pos­sibletoobtainhigh­resolutionneutrondiffractionspectraΔd/d≈2·10–3forbackscatteringdetector(2θ=140°)andΔd/d≈4·10–3for±90°­detectorsatd=2Åwiththefairlyshortflightdistance(~6.6m)betweenFourierchop­perandneutrondetectors[5].

Characterizationofmagneticmaterialwasperformedbymeasuringthemag­neticpropertieswithSingleSheetTester–SST,foramagneticpolarizationJ=50,…1500mT,sinusoidal,atfrequencyf=3,...50.200HzaccordingtorulesDIN50462.Theenergylossesseparationwasperformedinordertoidentifyandreduceeachcomponentoftheselosses:eddycurrentloss(Wcl);hysteresisenergyloss(Wh);excessloss(Wexc)duetoeddymicrocurrentthatoccursatthemovementofthedomainwalls.

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References[1] G.D.Bokuchava,V.L.Aksenov,A.M.Balagurov,V.V.Zhuravlev,E.S.Kuzmin,A.P.

Bulkin,V.A.Kudryashev,V.A.Trounov,“Neutron Fourier diffractometer FSD for in-ternal stress analysis: first results”,AppliedPhysicsA:MaterialsScience&Processing,v.74[Suppl1],2002,pps86–s88.

[2] A.M. Balagurov, G.D. Bokuchava, E.S. Kuzmin, A.V. Tamonov, V.V. Zhuk,“Neutron RTOF diffractometer FSD for residual stress investigation”,ZeitschriftfürKristallographie,SupplementIssueNo.23,2006,pp.217–222.

[3] P.Hiismäki,H.Pöyry,A.Tiitta,“Exploitation of the Fourier chopper in neutron dif-fractometry at pulsed sources”,JournalofAppliedCrystallography,Vol.21,1988,pp.349–354.

[4] A.M. Balagurov, I.A. Bobrikov, G.D. Bokuchava, V.V. Zhuravlev, V.G. Simkin,“Correlation Fourier Diffractometry: 20 Years of Experience at the IBR-2 Reactor”,PhysicsofParticlesandNuclei,2015,Vol.46,No.3,pp.249–276.

[5] G.D.Bokuchava,A.M.Balagurov,V.V.Sumin,I.V.Papushkin,“Neutron Fourier dif-fractometer FSD for residual stress studies in materials and industrial components”,JournalofSurface Investigation.X­ray,SynchrotronandNeutronTechniques,2010,Vol.4,No.6,pp.879–890.

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Scanning electron microscopy: a direct method of identifying pollen grains

I.Piroeva*,S.Atanasova­Vladimirova

Rostislaw Kaischew Institute of Physical Chemistry, Bulgarian Academy of Sciences

*piroeva@abv.bg

AsimplemethodofusingscanningelectronmicroscopytoobservepollengrainsThismethoddoesnotrequirefreezedrying,criticalpointdrying,orany chemical fixation procedures to prepare the specimens for scanning.Pollengrainscanbe identifieddirectly from thescanningelectronmicro­graphs,thusexpeditingthestudy.Thepollenhasbeentakenfromherbariummaterials.IthasbeenobservedandshotwithScanningElectronMicroscope(SEM)JEOLJSM­6390withoutanypreliminarytreatment.Pollensampleshasbeencoveredbygoldpowder.

Shotingshasbeenmade inmagnifications900and15000.While thesec­ondaryelectronimagingmode,themostcommoninuse,hasgreatvalueincharacterizingtheexinesurfaceitispossibletoobtainamorecomprehen­siverepresentationofpollengrainwallsbyexpandingthecapabilityofthesecondarymodeimagingdetectors.

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International Autumn School on Fundamental and Electron Crystallography, 8–13 October 2017, Sofia, Bulgaria

Mesoporous nanostructured ceria-titania mixed oxide doped with copper as catalysts for sustainable environmental

protection: Effect of preparation procedure

I.Genova1*,G.Issa1,R.Ivanova1,J.Henych2,M.Dimitrov1,D.Kovacheva3,V.Štengl2,T.Tsoncheva1

1 Institute of Organic Chemistry with Centre of Phytochemistry, BAS, Sofia, 1113, Bulgaria 2 Materials Chemistry Department, Institute of Inorganic Chemistry AS CR

3 Institute of Inorganic Chemistry, BAS, Sofia, 111, Bulgaria

*igenova@orgchm.bas.bg

Keywords:nanostructuredmetaloxides,totaloxidationofethylacetate,methanoldecomposition.

Recently,thesynthesisofnanostructuredmetaloxideshasbecomeahighlydevelopedfieldandattractedtheattentionofthescientistsintheirpursuitofstructuralpeculiaritiesandvariousunusualphysical,chemicalandcatalyticproperties.Aspecialinterestandeffortshavebeenfocusedontheprepara­tionofmetaloxideswithhighspecificsurfaceareaand/orcrystallinepar­ticlesinthenanosizedrangeusingvarioussyntheticroutes.Itwasreportedthatdopingoftitaniawithtransitionmetalscanincreaseitscatalyticactiv­ityandthermalstabilityasaresultofspecificinteractionand/orsynergismbetweenvariousmetaloxideparticles.Theaimofcurrent investigation istofollowtheeffectofcoppermodificationprocedureofmesoporousceria­titaniaoxidesontheircatalyticbehaviourinmethanoldecompositiontoCOandhydrogenasapotentialalternativefuelandethylacetateoxidationasarepresentativeVOCs.

Forthepurposeofinvestigationthemesoporousceriaand/ortitaniaoxidesweresynthesizedbytemplateassistedhydrothermaltechniqueusingCTABasstructuredirectedagent.Forthefirsttimea“chemisorption­hydrolysis”(CH)techniquewasappliedforthecopperloadingontheceriaand/ortita­niaoxidesandcomparedwiththeconventionalincipientwetnessimpregna­tion(WI)procedure.Thecoppercontentinallmaterialswasabout9wt.%.Theobtainedmaterialswerestudiedbyacomplexofphysicochemicaltech­niquessuchasXRD,N2physisorption,XRD,TEM,SEM,UV­Vis,Ramanand FTIR spectroscopies and TPR of H2. The catalytic properties of theobtainedmaterialswerestudiedinoxidationofethylacetateandmethanol

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decomposition.High surface areamesoporous ceria­titania binarymateri­als can be successfully synthesized using template assisted hydrothermaltechnique.Binaryoxidesupportsexhibitimproveddispersion,highsurfaceareaandporevolumecombinedwithexcellentoxygenmobility.Smalladdi­tivesofcoppertoceriaand/ortitaniaoxidespromotedtheircatalyticactivityin totaloxidationof ethyl acetate andmethanoldecomposition to syngas,butthiseffectisstronglyinfluencedbypreparationprocedure.Theapplied“chemisorption­hydrolysis” technique provided formation ofmore homo­geneously and finely dispersed copper specieswhich also possess highercatalyticactivityascomparedtotheconventionalincipientwetnessimpreg­nationtechnique.

AcknowledgementsFinancialsupportfromprojectDM­09/4/2016isacknowledged.

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Differences in the crystallization behavior of the Ba0.6Sr0.4Zn2Si2O7 phase in the presence

of oxides and noble metals

L.Vladislavova1*,Ch.Thieme1,2,Ch.Rüssel1

1 Otto-Schott-Institut, Chair of Glass Chemistry I, Jena University, Fraunhoferstr. 6, 07743 Jena, Germany

2 Fraunhofer Institute for Microstructure of Materials and Systems IMWS, Walter-Hülse-Str. 1, 06120 Halle, Germany

*liliya.vladislavova@uni­jena.de

Keywords:Nucleation,Crystallization,Platinum,ZrO2,Lowthermalexpansion.

TheeffectofdifferentnucleationagentstotheglasssystemBaO­SrO­ZnO­SiO2wasstudied.Glassesweremeltedwithdifferentconcentrationsofad­ditives such asZrO2,TiO2, andPt.The obtained glass ceramicswere in­vestigatedbydifferentmethodsalsowithrespecttotheircrystallizationbe­havior.ThecrystallizationkineticsofglassesfromwhichBa1–xSrxZn2Si2O7(0.1≤x≤0.9)solidsolutioncanbeprecipitatedisofincreasinginterest.ThisphasehasasimilarstructuretotheHTphaseofBaZn2Si2O7andpossessesvaluesofthermalexpansionclosetozeroorevennegative.Materialswhichdonotchangetheirdimensionduringheatingfindapplicatione.g.incookpanels,telescopemirrors,andothers.

For thecharacterizationof theglassceramics,X­raydiffractionwasusedtodeterminetheobtainedcrystallinephase.Thecombinationoflightscan­ningmicroscopyandscanningelectronmicroscopywasusedtocharacterizethemicrostructureandtodeterminethecrystallitesize.Applyingdifferentheatingratesinadifferentialscanningcalorimeter,enabledtocalculatetheactivationenergyusingtheequationsofOzawaandKissingeraswellastheAvramiparameters,whichprovidefurtherinformationonthecrystallizationprocess.

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New insights into the effect of a wash in water on the properties of Na3V2(PO4)2F3–yOy (0 ≤ y ≤2) materials

as positive electrodes for Na-ion batteries

L.H.B.Nguyena,b,f,T.Brouxa,b,f,P.SanzCamachoa,f,T.Baminea,f,A.Iadecolac,f,L.Bourgeoisd,E.Suarde,D.Carliera,f,

Ch.Masquelierb,f,gandL.Croguenneca,f,g

a ICMCB-CNRS, Université de Bordeaux, Bordeaux INP, 87 avenue Schweitzer, 33608 Pessac Cedex (France)

b Laboratoire de Réactivité et de Chimie des Solides, CNRS-UMR#7314, Université de Picardie Jules Verne, 33 Rue Saint Leu, 80039 Amiens Cedex (France) c Soleil Synchrotron, L’Orme des Merisiers, 91190 Saint-Aubin (France) d ISM, Université de Bordeaux, Bordeaux INP, 33405 Talence (France)

e ILL – Institut Laue-Langevin, 38000 Grenoble (France) f RS2E, Réseau Français sur le Stockage Electrochimique de l’Energie,

FR CNRS 3459, Amiens Cedex (France) g ALISTORE-ERI European Research Institute, FR CNRS 3104, Amiens Cedex (France)

Sodium­ionbatteries (SIBs) have recentlybeendeveloped as an alternatefor future sustainable energy storage system in place of the conventionallithium­ionbatteries(LIBs).AmongstthosewhichhavelatelybeenstudiedaspositiveelectrodematerialsforSIBs,Na3V2(PO4)2F3isthemostpromis­ingoneduetoitshighlystablepolyanionicframework,anditshightheoreti­calenergydensityof507Wh.kg–1(128Ah.kg–1atanaveragepotentialof3.95Vvs. Na+/Na)whichiscompetitivewithLiFePO4thathaslongbeenusedinLIBs[1–5].However,mostofthematerialsreportedintheliteraturetobeNa3V2(PO4)2F3 are in factoxygensubstitutedones (Fig.1). Inorder

Fig. 1. 3Drepresentationofthestructurewith a partial oxygen substitution for

fluorineinNa3V2(PO4)2F3–yOy(0<y≤2)[6].

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todetermine theeffectofoxygensubstitutionon thecrystalstructureandelectrochemicalpropertiesofNa3V2(PO4)2F3,Brouxet al. synthesisedasolidsolutionNa3V2(PO4)2F3–yOywithyrangingbetween0and0.5andrevealedthat thericher inoxygencontent, the lower theaveragedischargevoltageis,andthesodiumdeintercalationmechanismevolvedfromaseriesofbi­phasicreactionsfory=0toasolidsolutionalloverthecompositionrangeuptoy=0.5[6].Thepresenceofoxygendefectsinthesecompoundscanbeeasilydetectedbytheuseof23Naand31PMASsolid­statenuclearmagneticresonance(ss­NMR).

Inthiswork,thestudyontheformationofasolidsolutionNa3V2(PO4)2F3–yOywasextendedtohigheroxygencontent(0.75≤y≤2).Furthermore,theef­fectsofawashinginwateronthecrystalstructureandelectrochemicalper­formanceofthesematerialswerealsostudiedindetailsas:(i) thephaseswerealwaysobtainedwithasmallamountofimpurities(Na3VF6andNa5P3O10)whichcanbeeasilyremovedbyawashinginwater,(ii) asurginginterestintheelectrodeformulationinaqueoussolution,and(iii) thestabilityofthematerialwhenstoredinhumidconditionshastobedetermined.Withy<1,

thewashingsimplywashedawayalltheundesirable impurities. When the oxy­gencontentexceededy=1,thewashingledtoasignificantchangeinthecolouroftheobtainedpowdersandtoanunex­pectedmassivemassloss,especiallyforthemostoxidisedphase.Thesignificantmass loss in the oxidised phases wasdue to thedissolutionofanamorphousphaseandofthecrystallinedecomposi­tionproducts.Thedisappearanceoftheamorphous phasewas clearly observedbySEM(Fig.2).

Theresultsofourstudyrevealedthatthesolid solution Na3V2(PO4)2F3–yOy couldbeextendeduptoy=1(Fig.3).

Despiteofbeingreportedinliterature,anyofoureffortstostabilisethephaseswithy> 1 always led to the formation of anamorphousphaseinthepresenceofacrys­tallineonewhoseunitcellparametersare

Fig. 2. SEMimageofNa3V2(PO4)2FO2(y=2)powderbeforewashing(a),and

afterwashing(b).

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similar to those of Na3V2(PO4)2F2O(y = 1), or to the decomposition ofNa3V2(PO4)2F3–yOyintoseveralprod­ucts, includingNaVOPO4,Na4P2O7,andNaP1/3V2/3O3.

The discovery of a solid solutionformationinthecompositionrangefromy=0uptoy=1wasalsosup­portedbyacontinuousevolutioninthechemicalshiftsonthe31PMASNMR.InNa3V2(PO4)2F3,onemainresonant signal was recorded at δ= 6000 ppm corresponding to thedominantpresenceof theP(OVIII)4environment, the minor signal atδ = 4500 ppm was assigned totheP(OVIII)3(OVIV)environment,whichwascreatedby theexistenceofasmallamountofoxygendefectinthestructure.Uponoxygensubstitution,the intensityof thesignalatδ=6000ppmdiminishedwhilenewsignalsstartedtogrowatδ=3000,1500and0ppm,whichare thesignaturesofP(OVIII)2(OVIV)2,P(OVIII)1(OVIV)3,andP(OVIV)4,respectively.Theintensityofthelatestsignalreachedamaximumvaluewithatotaldisappearanceofothersignalsaty=1.5,suggestingthesolepresenceofP(OVIV)4environ­ment,whichisincontradictionwiththetheoreticalcompositionofthemate­rial(25%VIIIand75%VIV)(Fig.4).

Fig. 3. Theevolutionoftheunitcellparam­etersofNa3V2(PO4)2F3–yOy(0≤y≤2)(Space

groupAmam).

Fig. 4. 31P MAS NMR spectra ofNa3V2(PO4)2F3–yOy (0 ≤ y ≤ 2) re­cordedwitha30kHzspinning rateandunder2.35Tmagneticfield.

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Fig. 5.Ahigherzoominthediamagneticregimeof31PMASNMRspectraofNa3V2(PO4)2F3–yOy(0.75≤y≤2)recordedwitha30kHzspinningrateandunder

2.35Tmagneticfield.

Althoughtherewasonlyonesignal tobefoundonthe 31PMASNMRofNa3V2(PO4)2F3–yOywithy=1.5to2,ahigherzoomintothisregimerevealedthepresenceofadoubletwithdifferentrelativeintensity(Fig.5).Thisfind­ingsuggestedthattheremightbeasubtledifferenceinthelocalenvironmentinthosematerials.

ElectrochemicaltestswhichwereperformedinsimilarconditionsforeachcompositionofNa3V2(PO4)2F3–yOy–noCarbon­coatingandanappliedcur­rentofC/20–revealedthatonly1.5Na+ionscouldbeextractedfromthepristinematerialNa3V2(PO4)2F3–δOδ(δ~0)whiletwoNa+ionscouldbede­in­tercalatedreversiblyforallthemixedvalencecompositionsNa3V2(PO4)2F3–yOy(0<y≤2)showinganimprovedelectronicconductivity(Fig.6).

AcknowledgmentsTheauthorsthankSOLEIL(Gif­sur­Yvette,France)forSynchrotronX­rayspectroscopyexperimentsonROCKbeamline(proposalnumber20160282).TheauthorsalsoacknowledgetheRS2ENetworkforthefundingofLHBN’sPhDthesis,aswellasthefinancialsupportofRégionNouvelleAquitaine,of

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theFrenchNationalResearchAgency(STORE­EXLabexProjectANR­10­LABX­76­01 and SODIUM Descartes project ANR­13­ DESC­0001­02)andoftheH2020EuropeanProgram(ProjectNAIADES).

References[1] LeMeinset al.,J. Solid State Chem. 1999, 148 (2),260–277.[2] Tsirlinet al.,Phys. Rev. B 2011,84,014429­1­16.[3] Parket al.,Adv. Funct. Mater. 2014, 24 (29),4603–4614.[4] Serraset al.,Chem. Mater. 2013, 25 (24),4917–4925.[5] Bianchiniet al.,Chem. Mater. 2014, 26 (14),4238–4247.[6] Brouxet al.,Chem. Mater. 2016,28,7683–7692.

Fig. 6.TheelectrochemicalperformanceoftheNa3V2(PO4)2F3–yOy(0≤y≤2)materialsinsodiumcellsatC/20andwiththesameelectrodecomposition

(Activematerial:Cblack:PVdF=80:10:10bywt.%).

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International Autumn School on Fundamental and Electron Crystallography, 8–13 October 2017, Sofia, Bulgaria

Tridymite from Alšar under the SEM-EDS and XRD investigations – evidence for silicic volcanism

M.Lazarova,T.Sijakova­Ivanova,I.BoevandB.Boev

Faculty of Natural and Technical Sciences, “Goce Delcev” University, Stip, Macedonia

Keywords:volcanism,silicic,tridymite,perlite.

This paper presents the mineralogical and geochemical investigations oftridymiteandperliteusingXRD,SEM­EDSmethods.ThevolcaniccalderaAlšar is located in thewesternareaof thevolcaniccomplex in theKozufMountainatthefrontieroftheVardarzoneandthemetamorphiccomplexElenSupe, a relic of the oldPrecambrian continental crust.ThevolcanicactivityinthisareaofthevolcaniccomplexintheKozufMountainisrepre­sentedbyigneousrockswithdacitic­rhyoliticcomposition.Therearemanysedimentpyroclasticrocksinthecompositionofthecaldera,representedbyvolcanoclastictuffswithlayersoftridymiteandlayersofperlite.

Tridymite appears in layers, few meters thick and its color is white.Transparenttotranslucentwithvitreousluster.Thestreakiswhite.Hardnessis6½–7,whiledensityis2.28–2.33g/cm3.Cleavageisindistincton{0001}andimperfecton{1010}.Tridymiteandperliteareusuallyassociatedwithsilicicvolcanism.Thereisalsocrystobaliteandsmalleramountofopalintridymite’s composition. The appearance of opal is due to the diageneticchangesofthehigh­temperatureSiO2glass.Normalizedvaluesoftherareelementearthshow thedistribution in thesamemanneras in the igneousrocksatthevolcaniccalderaofAlšar.

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International Autumn School on Fundamental and Electron Crystallography, 8–13 October 2017, Sofia, Bulgaria

Investigation of the chemisorption of 3-aminopropylsilyl groups on silica gel using spectroscopy techniques

MihaBukleski*

Ss. Cyril and Methodius University in Skopje, Faculty of Natural Sciences and Mathematics, Institute of Chemistry, Arhimedova 5, 1000 Skopje,

Republic of Macedonia

*mihabukleski@yahoo.com

Keywords:3­aminopropyltrimethoxysilane(APTMS),Silicagel,chemisorption,DRIFTspectra,IRstudies.

Themainpurposeofusing3­Aminopropyltrimethoxysilane(APTMS)wastofunctionalizesilicagel’ssurfaceforitsfurtheruseinobtainingferroce­nylderivativethatcanexhibitcatalyticactivity.APTMShastwodifferentfunctionalgroups(aminoandmethoxymoieties)andcanthusbeusedasacouplingagent(spacer),especiallyonsilicagelasshowninFig.1.

Thepresentinvestigationisconcernedwithseveralquestions,oneofwhichis the spectroscopicdetectionof chemisorbedmoleculesofAPSon silicagel,assignmentofthebandsandderivingconclusionsonthepossiblecon­formationandformedbondsofthechemisorbedgroups.Theotherquestionconcernsspectroscopicinvestigationofpossiblechemicalreactionbetweentheferrocenyl­phosphinederivativeandtheAPSmolecules.Theanswertothesequestionsisimportantsinceitgivesdirectproveofabuiltheterogene­

Fig. 1. ChemicalreactionbetweenthefreeOHgroupsfromtheactivatedsilicagelandAPTMSinanhydrousconditions

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International Autumn School on Fundamental and Electron Crystallography, 8–13 October 2017, Sofia, Bulgaria

ous catalyst, because the so obtainedmodified silica gelwith ferrocenyl­phosphinemoleculesalreadyshowscatalyticproperties.

As a first step, a method for quantitative determination of the attachedAPTMSmoleculesasaminopropylsilil(APS)fragmentsonthesilicagel’ssurfaceisproposed.ThequantificationwasdonebymeansoftheDiffuseReflectance Infrared Fourier Transform (DRIFT) spectroscopy technique.TheappearanceandvanishingoftheIRbandsarisingfromtheOH,CH2andNH2vibrationswerefollowed.ThemaximumamountoftheAPSwasdeter­minedbyintegratingthespectrainthefrequencyrangeoftheν(CH2)/ν(CH3)vibrationsbetween3014and2808cm–1.Theresultswerefurtherconfirmedbycarbonelementalanalysis,AASandBETsurfacemeasurements.

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International Autumn School on Fundamental and Electron Crystallography, 8–13 October 2017, Sofia, Bulgaria

Pt(Cu) catalyst for methanol oxidation prepared by galvanic replacement on TiO2 powder support

N.Dimitrova1*,J.Georgieva1,S.Sotiropoulos2,Tz.Boiadjieva­Scherzer3,E.Valova1,S.Armyanov1

1 Rostislaw Kaischew Institute of Physical Chemistry, Bulgarian Academy of Sciences, Sofia 1113, Bulgaria

2 Department of Chemistry, Aristotle University of Thessaloniki, Thessaloniki 54124, Greece

3 CEST Kompetenzzentrum für elektrochemische Oberflächentechnologie GmbH, Wiener Neustadt, Austria

*ndimitrova@ipc.bas.bg

Pt(Cu)catalystwaspreparedbyphotodepositionofCuonTiO2powdersup­port,followedbypartialgalvanicreplacementofCubyPtinachloroplati­natesolution.Pt/TiO2catalystwaspreparedbyadirectphotodepositionofPtonTiO2supportforcomparison.Thesurfacemorphologyandcomposi­tionofthesampleswerecharacterizedbytransmissionelectronmicroscopy(TEM), energy­dispersive spectrometry (EDS) and X­ray photoelectronspectroscopy (XPS).The crystal structureof thePt(Cu)/TiO2 andPt/TiO2catalystswas examined byX­ray diffraction (XRD).The electrochemicaland photoelectrochemical behavior of both platinized TiO2 catalysts was

TEMmicrographandSAEDimageofPt(Cu)/TiO2catalyst

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International Autumn School on Fundamental and Electron Crystallography, 8–13 October 2017, Sofia, Bulgaria

evaluated by cyclic voltammetry, linear sweep voltammetry and chrono­amperometryexperimentsinthedarkandunderUVlightillumination.TheelectrocatalyticactivityofthePt(Cu)/TiO2catalysttowardsmethanoloxida­tionwasevaluatedandcomparedtoPt/TiO2catalyst.ThePt(Cu)/TiO2cata­lyst showed5 timeshighermasscatalyticactivity formethanoloxidationthanaPt/TiO2catalyst,furtherenhancedunderUVlightillumination.TheincreasedcatalyticactivityisassociatedwithmoreeffectivedispersionandbetterutilizationofPt,depositedbygalvanicreplacementofCu,aswellaswithenhancedelectron­holeseparationefficiency.

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International Autumn School on Fundamental and Electron Crystallography, 8–13 October 2017, Sofia, Bulgaria

Morphological characterization of organic-inorganic hybrid materials

N.Velikova1*,Y.Ivanova2,I.Spassova1

1 Institute of General and Inorganic Chemistry, Bulgarian Academy of Sciences, Sofia, Bulgaria

2 Department of Silicate Technologies, University of Chemical Technology and Metallurgy, Sofia, Bulgaria

*nina.e.v@abv.bg

Keywords:Sol­gel,silsesquioxane,hybridmaterials,mesoporousmaterials,surfactant.

Theobjectiveofthisworkisthesynthesisofmesoporousorganic­inorganicsilicabasedmaterialsbysol­gelmethod,aswellastoinvestigatetheinflu­enceofthereactionconditionsonthematerialsmorphology.

Thematerialsweresynthesizedbysol­gelmethodbyusingofPluronicP123(nonionic triblock copolymer) as a structure directing agent, silsesquiox­ane (Bis[3­(trimethoxysilyl)propyl]amine ([(CH3O)3Si(CH2)3]2NH)) andtetraethyl orthosilicate (Si(OC2H5)4) under acidic condition.Thematerialsmorphologywas investigated by byX­ray diffraction, Scanning ElectronMicroscopy, Transmission Electron Microscopy and nitrogen adsorptionmeasurements after removing of P123 by extraction in acidic solution.Obtainedsampleshaveparticle­likemorphology,highvaluesofporesize,porevolumeandsurfaceareaafterextractionoftheusedtemplate.

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International Autumn School on Fundamental and Electron Crystallography, 8–13 October 2017, Sofia, Bulgaria

Structure and magnetic properties of Sr3Co2Fe24O41

P.Peneva1*,T.Koutzarova1,S.Kolev1,Ch.Ghelev1,B.Vertruyen2,R.Closset2,R.Cloots2andA.Zaleski3

1 Institute of Electronics, Bulgarian Academy of Sciences, 72 Tsarigradsko Chaussee, 1784 Sofia, Bulgaria, е-mail: petya_venelinova_peneva@abv.bg

2 LSIC, Chemistry Department B6, University of Liege, Sart Tilman, B-4000 Liege, Belgium

3 Institute of Low Temperature and Structure Research, PAS, 50422 Wroclaw, Poland

*petya_venelinova_peneva@abv.bg

Themultiferroics aremultifunctionalmaterialswhere twoormoreof theprimaryferroicproperties(ferromagnetism, ferroelectricity, ferroelasticity, ferrotoroidicity)coexist.Theinterestinmagneto­electricmultiferroicmate­rialsinwhichferroelectricityandferromagnetismarebothpresentisduetothemagneto­electriceffect.Themainrequirementtotheapplicationsofthemagneto­electricmultiferroicmaterialsisthatthemagneto­electriccouplingbebothlargeandactiveatroomtemperatureandthemagneticorderingtem­peraturebehigh.TheZ­typehexaferriteSr3Co2Fe24O41exhibitsamagneto­electriceffectatroomtemperature.

WereportstudiesofstructuralandmagneticpropertiesofSr3Co2Fe24O41inpowdersandinbulkform.Theprecursorpowderswerepreparedfollowingthesol­gelauto­combustionmethodandsynthesizedat1200°CtoproduceSr3Co2Fe24O41.Toprepare thebulksample, theSr3Co2Fe24O41powderwaspressed,heattreatedat1200°Cfor5hoursandrapidlyquenchedtoroomtemperature.

TheXRDspectraofthepowdershowedthecharacteristicpeakscorrespond­ingtotheZ­typehexaferritestructureasamainphaseandsecondphasesofCoFe2O4.TheSEMimagesofthepowdersampleshowsthattheparticlesarewellagglomeratedtoformclustersofdifferentsizesandshapes.Inthebulksample,weclearlyobservedlargeregionsofthehexagonalparticleswithastructureorderedalongthecaxis.Magneticphasetransitionsinthetemperaturerangeof4.2-300Kwerealsoobservedconnectedtothedifferentspinstructure.

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International Autumn School on Fundamental and Electron Crystallography, 8–13 October 2017, Sofia, Bulgaria

Microstructural characterization of black tourmaline

R.Angelov,B.Georgieva,L.AngelovaandD.Karashanova*

Institute of Optical Materials and Technologies, Bulgarian Academy of Sciences, Acad. Georgy Bonchev str., bl. 109, 1113 Sofia, Bulgaria

*dkarashanova@yahoo.com

“Tourmaline” is the unifying name of a group of boron silicatemineralswithcommoncrystalstructureandalargevarietyofelementsintheircom­position.Togetherwithmuscovite,tourmalineisthemineralwiththemost

Schorl,RhombohedralSGR3m(160)a=15.97c=7.16

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International Autumn School on Fundamental and Electron Crystallography, 8–13 October 2017, Sofia, Bulgaria

applications in the industry,due to theexceptionalphysicalandchemicalpropertiesashighpiezoandthermo­electricity,radiationinthefarinfraredregion,significantcatalyticactivityetc.

Themicrostructureandthephasecompositionofblacktourmaline–schorl,from Vladaya vein in Vitosha Mountain are studied by means of HighResolutionTransmissionElectronMicroscopy(HRTEM)andXRDanalysis(PhaseidentificationaccordingtoPDF85­1811[PDF­2,ICDD]).

BrightfieldandHRTEMmicrographsandselectedareaelectrondiffraction(SAED)patterns–poly­andsinglecrystalline,receivedalongdifferentzoneaxesarepresented.

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International Autumn School on Fundamental and Electron Crystallography, 8–13 October 2017, Sofia, Bulgaria

Goniometry in 21-st century. Why not?

S.Dencheva

Sofia University “St. Kl. Ohridski”

stefka.dencheva@gmail.com

In the ages of nanotechnologies,modern scientists seem to have lost thetastefortheclassicalgoniometricresearch.ButasfarasIknow,thisistheonlywaytoanswerthequestion:“Whatsimpleformsactuallygrowinthecrystal?”Andthisissuehasnotlostitsrelevanceduetotheanisotropyofthepropertiesofsubstanceswithsymmetrylowerthanthecubic.Andif,thankstoGoldschmidt,thesimpleformsof“grandfathered”mineralsareknown,itisnotsofortherecentlydiscoveredandthemicroscopicones.

Thisworkaimstobrieflyintroduceyoutotheauthor’seffortstodeterminetheMiller’sindicesofsimpleformsofselectedminerals,bothatmacroormicrolevels.

AcknowledgementsIwouldliketoexpressmyacknowledgementstoProf.GeorgiKirov,whointroducedmetotheworldofcrystallographyandhasbeensupportingmeinanumberofstudies.

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International Autumn School on Fundamental and Electron Crystallography, 8–13 October 2017, Sofia, Bulgaria

Surface morphology of wine crystals

S.Atanasova­Vladimirova*,I.Piroeva

Rostislaw Kaischew Institute of Physical Chemistry, Bulgarian Academy of Sciences

*statanasova@ipc.bas.bg

Tartrates, affectionately known by industry professionals as “wine dia­monds”,are tiny,crystallinedeposits thatoccur inwineswhenpotassiumandtartaricacid,bothnaturallyoccurringproductsofgrapes,bindtogethertoformacrystal.Itlookslikesugargranulesandisfoundatthebottomofthebottleorstucktothestopper.Inbottledwine,thepresenceoftartaricacidanditssalts,potassiumbitartrateandcalciumtartrate,canresultinformationofcrystallineprecipitates.Unpurifiedpotassiumbitartratecan takeon thecolorofthegrapejuicefromwhichitwasseparated.

Thescanningelectronmicroscope(SEM)viewssurfacesofwinecrystals.Theyhavingdifferentsurfacemorphologiesandhabitswereobtained:thinplates,prismfaces,pyramidgrainetc.

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International Autumn School on Fundamental and Electron Crystallography, 8–13 October 2017, Sofia, Bulgaria

In vitro bioactive gelatin/silver containing sol-gel glasses composites: FTIR and SEM analysis

L.Radev1*,O.Kersten2,I.Michailova3,T.Dimova4*,DianaZaimova1

1 University of Chemical Technology and Metallurgy, Department of Fundamental Chemical Technology, Sofia, 1756, Bulgaria

2 Anhalt University of Applied Science, Department of Engineer Science, Koethen, 06366, Germany

3 University of Chemical Technology and Metallurgy, Department of Silicate Technology, Sofia, 1756, Bulgaria

4 Department of Pharmaceutical Science, Medical University, Varna, 9000, Bulgaria

*biotan@abv.bg

Themainobjectivesofthepresentedstudyisthepreparationof80BG/20G(inwt.%)compositesbetweensol­gelglasses(BG)intheSiO2–CaO–P2O5–xAg2O (x=0, 1, 2 and4wt.%) systemandgelatin (G), after soaking in1.5SBFsolutionsfor12daysinstaticconditions.ThestructureandinvitrobioactivityofthepreparedcompositeswereexaminedbyXRDandFTIR.

XRDforthecomposites,beforesoakingin1.5SBFsolutions,revealedthepresenceofdifferentCaCO3crystallinephases,suchasaragonite,calciteandvaterite.Inthepreparedsamples,XRDalsodetectedthepresenceofinsituformedhydroxyapatite,accompaniedwithwollastonitephase.FTIRofthestudied80BG/20Gcomposites,aftersoakingin1.5SBFsolutions,provedtheformationofB­typecarbonatecontactinghydroxyapatite(bio­apatite)on their surface.SEM­EDXresultsof the soaked samples showthepresenceofHAaggregatesonthesoakedsurceases.Onthebasesofresultsobtainedwecanconclude that the synthesizedBG/Gcompositesareinvitrobioactive.

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International Autumn School on Fundamental and Electron Crystallography, 8–13 October 2017, Sofia, Bulgaria

Chemical bonding and nonlinear optical properties of TeO2–Bi2O3–B2O3 glasses

T.Tasheva*,V.Dimitrov

Department of Silicate Technology, University of Chemical Technology and Metallurgy, 8 Kl. Ohridski Blvd, 1756 Sofia, Bulgaria

*tina.tasheva@gmail.com

OxideglassesinthesystemTeO2–Bi2O3–B2O3arepreparedusingaconven­tionalmelt quenching method. The polarizability approach based on theLorentz­Lorenzequationisapplied.Theopticalbasicityandtheoxideionpolarizabilityareestimated.Thetheoreticalrefractiveindexandtheenergygapoftheglassesarealsoestimated.Thechemicalbondingoftheglassesiselucidatedonthebasisoftheinteractionparameterandthesinglebondstrengthofanaveragecation­oxideion(M–O)bond.

Itisfoundthattheglassespossessrelativelyhighvaluesoftheopticalba­sicityand theelectronicoxide ionpolarizability, relatively lowvalues fortheaveragesinglebondstrengthand lowvaluesof the interactionparam­eter.TherefractiveindexbasedthirdordernonlinearopticalsusceptibilityoftheglassesisestablishedusinggeneralizedMiller’sruleandthree­photonmodel.Theglassespossesscomparativelyhighthirdordernonlinearopticalsusceptibility(~10–13esu).Theseresults indicatefor thepresenceofweakchemicalbondswhichareformedbetweenTeO4,BiO6,BO4andBO3groupsconfirmedbyIRspectralanalysis.Structuralmodelofthestudiedglassesisproposed.

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International Autumn School on Fundamental and Electron Crystallography, 8–13 October 2017, Sofia, Bulgaria

Canine seminal plasma – functions and interaction with capacitation

D.Daskalova,T.Tsvetkov*,K.Lazov,D.Gradinarska,M.Hristova,M.Ivanova

Institute of Biology and Immunology of Reproduction – BAS

*tsvetan_tsvetkov_88@abv.bg

Keywords:chromatography,seminalplasmaproteins,hyperactivation,capacitation,spermatozoa.

Semenisaheterogeneousandcomplexcellsuspensioninaproteinrichfluidwithvariousfunctions,someofthemwellknown,otherstillunexplained.Theaimofthecurrentresearchisfocusedoncanineseminalplasmaproteinsandtheirfunctionalrelationshipwithcapacitationofspermatozoa.Attemptsweremadetoidentifycanineseminalplasmaproteinswitheffectonspermcapacitation andmotility.HighPerformanceLiquidChromatographywasdoneand4seminalplasmaproteinfractionswereobtainedandfurtherchar­acterizedbyelectrophoresis(7.6–200kDa).Computer­assistedspermanaly­sisafterincubationofspermatozoawithseparatedseminalplasmaproteinsrevealedthatFraction1,consistingofhighmolecularweightproteins(70–200kDa), could increase thepercentageof spermatozoawithprogressiveandrapidmotility.IncubationwithseminalplasmaproteinsfromFraction1leadstoasignificantincreaseofVCL(Curvilinearvelocity)anddecreaseofLIN(Linearity)ofspermatozoa,whencomparedtotheothertestsamplesandthecontrolsample.Proteinswithhighmolecularweightprobablyhavethemostsignificantinfluenceontheprocessofhyperactivationandcapaci­tationofcaninespermatozoa.

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International Autumn School on Fundamental and Electron Crystallography, 8–13 October 2017, Sofia, Bulgaria

Crystallochemistry of M2+-hydroxysalt minerals

Z.Delcheva

Institute of Mineralogy and Crystallography – Bulgarian Academy of Sciences, “Acad. Georgi Bonchev” block 107, 1113 Sofia

zlatttt@abv.bg

Thehydroxy­saltmineralsformasubstantialpartofthemineralogicalno­menclature.Theyarenormallystableoverasmallrangeofexternalcondi­tions (such as Eh, pH, T, P, concentration of solutions, component ratio,impurities,etc)aswellas theyarecommonlyassociatedwithmanyothermineralsofsimilarcompositionsinsameparageneses.Incontrasttothesta­blerock­formingmineralsthehydroxyl­saltmineralsreacttoslightenviron­mentalchangesthroughchangesinthecrystalstructure.Therefore,theyareconvertedeasily(andveryoftenreversibly)intoeachotherunderenviron­mentalchanges.

Theexcellent resistanceofzincandzinc­platedsteelundernaturalcondi­tionsisduetotheformationofaprotectivecorrosionlayerofzinchydroxy­salts(zincrust).Themineralcompositionofthislayerdependsstronglyontheexposureenvironment,anditsprotectiveeffectisdeterminedbythemor­phologyandarrangementofthecrystals[1].Thezinchydroxysaltsarealsothesubjectofstudybecauseofsomeotherusefulproperties:ionexchangeand sorption properties, photocatalytic properties, hydrogen­gas sensingproperties,flameretardantproperties[2,3]aswellastheirapplicabilityasprecursorsofnanostructuredZnOforvariousapplications[4,5].

Themutual transformations of the Zn2+ hydroxyl­salt minerals with gen­eral formulaZn2+(OH)2–xAx/n

n– .±H2O,where inAareSO42–(osakaite,na­

muwite, lahsteinite, gordaite), Cl– (simoncolleite), NO3– (synthetic NO3­

simoncolleite)andCO32–(hydrozincite)wereinvestigated.Thebipolarchar­

acterofthedominantanion(OH–)predetermineslayeredcharacterofstruc­turesoftheinvestigatedminerals[6],whiletheabilityofZn2+iontosettlebothintetrahedralandoctahedraloxygencoordinationexplainsthespecificoctahedral­tetrahedral construction of the layers inZn hydroxy­salts. Themainbuildingunitisthebrucite­likelayerinwhichoneseventh(osakaite,namuwite,lahsteinite,gordaite)oronefourth(simoncolleite,hydrozincite)oftheoctahedralsitesarevacant.Thezinccationsarelocatedoneithersideofthevacantoctahedralpositions.These(tetZn2+)aretetrhedrallycoordinated

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International Autumn School on Fundamental and Electron Crystallography, 8–13 October 2017, Sofia, Bulgaria

bythreeOH­groupsofbrucite­likelayersandawatermolecule(inosakaite,NO3­simoncolleite),aCl–anion(ingordaiteandsimoncolleite),OatomofCO3

2– anion inhydrozincite.Thus, theoctahedral­tetrahedral layer canbecharacterizedas“interrupteddecoratedsheet”[7].

Theinteractionofmineralswithchloride,nitrate,sulfateandcarbonatesolu­tionswithaparticularattentiontothereactionmechanismswasstudied.TheinitialandnewlyformedphasesweremainlycharacterizedbyX­raypowderdiffraction,becausethepowderX­raydiffractiondataadequatelyreflectthechanges in thecompositionof the systems.TheSEM investigationswereusedtorevealreaction(transformation)mechanisms.

Theinterpretationofthemutualtransformationmechanismisbasedonthecrystal­chemical and morphological similarities between parent and newformedphase.

Twotypeoftransformationmechanismswerefoundtoproceed:adissolu­tion­precipitationprocess(DSP)andasolidstatetransformation(SST).

The results reveal the crucial role ofweakly bonded components for thestructurestability.Suchcomponentsarenon­hydroxylanions(Cl,CO3,SO4,NO3), watermolecules and interlayer cations. Thus, the ratio octahedral/tetrahedral positionof the layer dependsonnon­hydroxyl anion– sulfateanionrequiresformationof layerwith6:1ratioandmonodentatebondingof theanion. In thecompositionswith3:1anionsdictate theformationofthestructureswithdifferentsymmetry:Cl–anionscausethecrystallizationofthemineralswithrhombohedralcell,whiletheCO3

2–,NO3––orthorhom­

biccell.Thechangeoftheenvironmentalcompositionleadstoreactionbe­tweennon­hydroxylanionsof the interlayerandthesolutioncomponents.Asaresult,newtypeofinterlayerisformed.Ifitiscompatible(i.e.satisfiesthebond­valencerequirementsoftheoctahedral­tetrahedrallayer),thesolidstatetransformationisoccurred.Ifduringtheexchangereaction,thecompo­nentsofthenewinterlayercannotformastablesystemofhydrogenbonds,the crystal is destroyed and the transformation becomes trough theDSP­mechanism.Insomecases,anewsystemofH­bonds,preservingthelayeriscreatedandtransformationproceedsthroughSST­mechanism.

References

[1] Volovitch,P.,Allely,C.,Ogle,K.2009.Understandingcorrosionviacorrosionproductcharacterization:I.Casestudyof theroleofMg­alloying inZn­Mgcoatingonsteel.Corrosionscience.51,1251–1262.

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[2] Hongo,T.,Lemur,T.S.,Satokawa,S.,Yamazaki,A.2010.ChromateadsorptionandpHbufferingcapacityofzinchydroxysalts.Appl.ClaySci.48,455–459.

[3] He,P.,Gao,H.D.,Wu,L.B.,Jiang,Z.W.,Wang,G.L,Li,X.M.2013.PorousZnOsheets transformed fromzinc sulfatehydroxidehydrate and their photoluminescenceperformance.ActaPhys.­Chem.Shin.29,874–880.

[4] Moezzi,A.,Cortie,M.B.,McDonagh,A.M.2013.Zinchydroxidesulfateanditstrans­formationtocrystallinezincoxide.DaltonTrans.42,14432–7.

[5] Liang, W., Li, W., Chen, H., Liu, H., Zhu, L. 2015. Exploring electrodepositedflower­like Zn4(OH)6SO4.4H2O nanosheets as precursor for porous ZnO nanosheets.ElectrochimicaActa.156,171–178.

[6] Hawthorne, F. C. 1992. The role of OH and H2O in oxide and oxysalt minerals.ZeitschriftfurKristallographie.201,183–206.

[7] Hawthorne,F.C.,Schindler,M.2000.Topologicalenumerationofdecorated[Cu2+ϕ2]Nsheetsinhydroxy­hydratedcopper­oxysaltminerals.Can.Mineral.38,751–761.

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International Autumn School on Fundamental and Electron Crystallography, 8–13 October 2017, Sofia, Bulgaria

Characterization of cuprite (Cu2O) particles from waste copper cake

GyunverHodjaoglu

Institute of Physical Chemistry – Bulgarian Academy of Sciences (IPC-BAS) Acad. G. Bonchev Str., block 11, 1113 Sofia, Bulgaria

e­mail:gyunver@ipc.bas.bg

Coppercakeisanindustrialvaluablesecondarywasteproductproducedinthehydrometallurgicalzincplantaftercementationstageofcopperionswithzincpowder.Thewasteisdepositedaswetsedimentforexportorstorage.Dependingon thereactionconditions thecakecontainsahugeamountofcupriteparticles formedbycementationprocess and restparticles formedfromthesolutionimpurities.Withtheleachingandecologicalaspectscop­percakefromKCM­Plovdivhasbeentreatedwithdilutedsulphuricacidforutilizationofthecupritecontent.Inthisstudythedrysamplesbeforeandaf­terleachingprocedurewerecharacterizedbyScanningElectronMicroscopy(SEM)forobservationoftheparticlesmorphology(Cu2O)andappearanceofnewreactionproducts(CuSO4).EnergyDispersiveSpectroscopy(EDS)wasalsoappliedforthechemicalcharacterizationoftheobservedparticles.TheresultsshowthatSEM­EDXisapowerfultechniqueforinitialfastde­terminationof leachingefficiencyanddetectionofcopper sulphatemicrocrystals.ItwasfoundthatthestartingwastecontainslargeamountofzincsulphatewhereasthefinalleachedcakeisZn­free.TheSEManalysisisveryperspectiveforfurthercharacterizationsofothertypesofcopper­Mecakes,theirchemicalcharacterizationandstudyingunidentifiedsolidparticlesdur­ingdepositionandtestleaching.

AcknowledgementsThe author gratefully acknowledge the financial support of ProjectBG05M2OP001­2.009­0023,“Establishmentanddevelopmentofscientificpotentialforthespecializationsofphysicalchemistryandelectrochemistry”,fundedbytheOperationalProgram“ScienceandEducationSmartGrowth”,co­funded by the European Union through the European Structural andInvestmentFunds.