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1

Investigations of hydroxyapatite crystals in oral care products using the TEM method

Pajchel Ł., Malicka A., Pajchel A., German R., Kolodzijski W.

Engineering of Biomaterials

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2018

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Vol. 21, no. 148

42

2

Band electronic structure and dielectric functions of (C3N2H5)2SbF5 crystals

Andriyevsky B., Czapla Z.

Zeszyty Naukowe Wydziału Elektroniki i Informatyki Politechniki Koszalińskiej

|

2016

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Nr 10

51--60

EN

Structural and electronic properties of the ferroelastic crystal (C3N2H5)2SbF5 of the molecular type were studied by ab initio methods in the framework of the density functional theory. Band electronic structure, density of electronic states and dielectric functions in the range of valence electrons excitations of the crystal in the monoclinic phase (space group no. 11) have been obtained using the plane waves, ultrasoft pseudopotentials and van-der-Waals corrections. The electronic values obtained are discussed from the viewpoint of the layer-type crystal structure of (C3N2H5)2SbF5.

PL

Strukturalne i elektronowe właściwości ferroelektrycznego kryształu (C3N2H5)2SbF5 typu molekularnego zostały obliczone w ramach teorii funkcjonału gęstości (DFT) z wykorzystaniem odpowiedniej metody z pierwszych zasad (ab initio). Pasmowa struktura elektronowa, gęstość stanów elektronowych i funkcje dielektryczne w zakresie wzbudzenia elektronów walencyjnych kryształu zostały obliczone dla strukturalnej fazy jednoskośnej (grupa przestrzenna no. 11) z wykorzystaniem płaskich fal, super pseudopotencjałów miękkich i uwzględnienia poprawek na oddziaływania międzyatomowe typu van-der-Waalsa. Otrzymane wielkości elektronowe zostały omówione pod kątem warstwowej struktury krystalicznej (C3N2H5)2SbF5.

3

Investigation on growth, optical and thermal properties of stilbazolium derivative crystal: 4-N,N-dimethylamino-40-N0-methylstilbazolium 2,4-dimethylbenzenesulfonate

Md Zahid I., Kalaiyarasi S., Kumar M. K., Ganesh T., Jaisankar V., Kumar R. M.

Materials Science Poland

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2016

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Vol. 34, No. 4

811--818

EN

Metathesis ionic exchange reaction process was used to synthesize a novel nonlinear optical material: 4-N,N-dimethylamino-4′- N′-methylstilbazolium 2,4-dimethylbenzenesulfonate (DSDMS). The growth of DSDMS single crystals was carried out by adopting the solution growth technique. The crystal perfection and lattice parameters were elucidated from single XRD and powder XRD, respectively and its morphology was interpreted by WinXMorph program. FT-IR and Raman spectral analyses confirmed the existence of functional groups and their corresponding vibrational modes. UV-Vis spectral studies revealed the optical transmission region. Mechanical stability of the crystal was determined from Vickers microhardness number Hv, Meyer’s index n and elastic stiffness constant C11. Dielectric and thermal behavior of the grown crystal were elucidated by using impedance analyser and thermogravimetric analysis.

4

Influence of uniaxial stresses on electronic and opticalproperties of β-K2SO4 crystal

Andriyevsky B., Jaskólski M., Stadnyk V. Y., Romanyuk M. O., Kashuba Z. O., Romanyuk M. M.

Materials Science Poland

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2015

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Vol. 33, No. 1

11--17

EN

In view of possible practical applications of transparent crystals for mechanical stress sensors, theoretical investigation of piezo(elasto)optic effect in crystals might be useful for searching for proper materials, possessing large coefficients of elasto-optic effect, and for determination of uniaxial stress directions of maximum piezo-optical sensitivity. The influence of the uniaxial stresses on the electronic band structure, density of states, and optical properties of potassium sulphate crystal β-K2SO4 have been studied in the framework of the density functional theory using the ab initio CASTEP code. Increase in the band gap, Eg of the crystal takes place for three crystallographic directions and for moderate uniaxial stresses, σ< 1.5 GPa. Dependencies of principal refractive indices and polarizabilities upon principal uniaxial stresses are discussed together with other features of electronic structure of the crystal.

5

Czochralski Growth and Properties of Scintillating Crystals

Yoshikawa A., Chani V., Nikl M.

Zeszyty Historyczne Politechniki Warszawskiej

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2014

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z. 16

135--149

EN

The Czochralski method is one of the very few melt growth techniques that are industry friendly when considering the combination of quality, dimensions, and cost of the produced crystals suitable for their commercialization in scintillation detectors. This method is one of the oldest and most developed crystal growth processes regarding an adequate understanding the physical phenomena observed during solidification process and its practical expansion especially in the industrial scale production. It allows controllable formation of single-crystalline cylindrical ingots of various inorganic scintillation materials. The review summarizes recent progress on the Czochralski growth of a number of scintillation materials. The oxide crystals are mainly considered including the Ce and Pr-doped RE3Al5O12, RE = Y, Lu, aluminum garnets and newly discovered ultraeffcient Ce-doped Gd3(Ga,Al)5O12 multicomponent garnet, high density PbWO4 and CdWO4 tungstates, Ce-doped RE2SiO5, RE = Y, Gd, Lu, oxyorthosilicates and (Y,Lu)AlO3 aluminum perovskites and finally the classical Bi4Ge3O12 scintillator. Additionally, the details of the growth of other practically important non-oxide crystals, namely the Ce and Eu-doped LiCaAlF6 neutron and ultraeffcient Ce-doped LaBr3 scintillators, are discussed. The potential of novel micro-pulling down growth method is briefly described in the combinatorial search for new scintillator materials. Selected luminescence and scintillation characteristics including the spectra and decay kinetics, light yield and radiation resistance are also illustrated and overviewed.

6

Influence of rod diameter on acoustic band gaps in 2D phononic crystal

Gruszka K., Nabiałek M., Szota M.

Archives of Materials Science and Engineering

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2014

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Vol. 68, nr 1

24--30

EN

Purpose: The purpose of this paper is to investigate influence of changing the fill factor (or rod diameter) on acoustic properties of phononic crystal made of mercury rods inside of water matrix. Change in construction of primary cell without changing the shape of rod may cause shifts in bands leading to widening of forbidden band gaps, which is the basis of modern composite material designing process. Design/methodology/approach: Band structure is determined by using the finite element study known as finite difference frequency domain simulation method. This is achieved by virtual construction and simulation of primary cell of phononic crystal. Phononic crystals are special devices which by periodic arrangement of properties related to the sound can affect the transmission of acoustic waves thru their body. Findings: The fill factor/rod diameter has a significant influence on the acoustic band structure of studied phononic crystal which can be divided in two mainly effects: fission and compression of band structure. Research limitations/implications: In order to better understand basic properties of phononic crystals and to get full control over the band gaps a series of similar calculations should be done for broader range of frequencies covering both infrasound and ultrasound wavelength regions. Also structures of other cut shape of rod and different primary cell structure resulting in diverse phononic crystal structure should be investigated in the future. Practical implications: Phononic crystals are important devices in variety of applications ranging from noise control through acoustic computing, health applications and entertainment up to military applications. Therefore full knowledge about specific working conditions and elementary properties is necessary for complete control in targeted applications. Controlling the fill factor is one of the simplest methods to achieve specific band gap positions and widths. Originality/value: The novelty is in use of different phase materials with similar acoustic characteristics affecting the hole sonic properties of device manifested by their calculated band structure. The target group are scientists interested in practical applications of various acoustic materials.

7

Świat minerałów - Terra Mineralia, wystawa we Freibergu (Saksonia)

Probierz K.

Przegląd Górniczy

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2012

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T. 68, nr 10

102--105

PL

Scharakteryzowno nową wystawę minerałów Terra Mineralia zorganizowaną we Freibergu (Saksonia). Wystawę zorganizował tamtejszy uniwersytet TU-Bergakademie, najstarsza nadal funkcjonująca uczelnia górnicza na świecie założona w 1765 roku. Oddane w wieczyste użytkowanie uczelni okazy (ponad 3500) były gromadzone przez okres około 50 lat przez kolekcjonerkę i miłośniczkę minerałów, mecenasa sztuki Panią dr E. Pohl-Ströher. Efektowna ekspozycja umożliwia zapoznanie się z pięknem świata kryształów i minerałów, zróżnicowaniem ich barw, rozmiarów i kształtów. W kolekcji zgromadzono okazy pochodzące z wszystkich kontynentów. Omówiono ponadto zarys budowy geologicznej obszaru występowania srebronośnych złóż rud Zn-Pb, historię górnictwa rejonu oraz miasta założonego w XII wieku a także uczelni TU-Bergakademie Freiberg.

EN

This paper presents a new-found mineral exhibition Terra Mineralia, which took place in Freiberg, Saxony. It was organized by TU-Bergakademie, the first, still operating mining university in the world, founded in 1765. The university has been granted the right of perpetual usufruct of the pieces of art (above 3500) which have been gathered for around 50 years by the collector and lover of minerals, the patron of art Mrs. Ph.D. E. Pohl – Ströher. The glamorous exhibition enables one to get familiar with the beauty of the world of crystals and minerals, their differentiation of colour, size and shape. The collection consists of pieces from all continents. Besides, this paper describes the outline of geological structure in the area of argentiferous ore deposits Zn-Pb, the history of local mining industry, the city founded in the 17th century as well as the TU-Bergakademie University. .

8

The technology of obtaining ferroics solid solutions Csx(NH4)1-xLiSO4

Czaja P., Borkowski S.

International Journal of Applied Mechanics and Engineering

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2010

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Vol. 15, no 2

469-475

EN

The research paper presents the technology of obtaining the solid solutions Csx(NH4)1-xLiSO4 where: x=0, 0.95, 1. The obtained materials were verified by the X-ray powder diffraction method. X-ray powder diffractometers together with selected indicators for: CsLiSO4, NH4LiSO4, NH4LiSO4 and Cs0.95(NH4)0.05LiSO4 were presented. Lattice constants for the solid solution of Cs0.95(NH4)0.05LiSO4 was evaluated.

9

Development of crystals based on cesium iodide for measurements of gamma radiation and alpha particles

Pereira M. C. C., Filho T. M., Hamada M. M.

Nukleonika

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2009

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Vol. 54, No. 3

151-155

EN

During the past 50 years, scintillators have been among the most important nuclear radiation detectors. Inorganic scintillators are widely used in experimental nuclear physics, high energy physics, nuclear medicine, nuclear tomography, environmental studies and many other fields of use. Scintillation crystals based on cesium iodide (CsI) are matters of relatively low hygroscopy, high atomic number, easy handling and low cost, characteristics that favor their use as radiation detectors. In this work, the growth of pure CsI crystals, CsI:Br and CsI:Pb, using the Bridgman technique, is described. Ions of divalent lead (Pb2+) doped in the crystal structures are efficient emission centers and their application as scintillators is still the reason for intensive studies. Recently, promising results have been found for crystals of CsI doped by bromine (Br) for their use as radiation detectors. The concentration of the bromine doping element (Br) was studied in the range from 1.5 × 10–1 M to 10–2 M and the lead (Pb) in the range from 10–2 M to 5 × 10–4 M. To evaluate the scintillators developed, systematic measurements were carried out for luminescence emission and luminescence decay time for gamma radiation, Vickers microhardness assays, and analysis of crystals response to the gamma radiation, in the energy range from 350 keV to 1330 keV, and alpha particles from a 241Am source, with energy of 5.54 MeV. The obtained values for luminescence decay time for CsI:Br and CsI:Pb crystals, were from 13 to 19 ns.

10

Room-temperature ferromagnetism in Fe-doped Na0.5Bi0.5TiO3 crystals

Wang Y., Xu G., Yang L., Ren Z., Wei X., Weng W., Du P., Shen G., Shen G., Han G.

Materials Science Poland

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2009

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Vol. 27, No. 2

471--476

EN

Fe-doped Na0.5Bi0.5TiO3 crystals were synthesized and studied by X-ray diffraction, X-ray spectroscopy, scanning electron microscopy, high-resolution transmission electron microscopy, and magnetic property measurement system. Room-temperature ferromagnetism was observed in Fe-doped Na0.5Bi0.5TiO3 crystals. It was found that the magnetism of Na0.5Bi0.5TiO3crystals can be controlled by the Fe dopant concentration. The magnetism of the Fe-doped Na0.5Bi0.5TiO3 crystals develops from diamagnetism to ferromagnetism and paramagnetism on increasing the Fe doping concentration from 0 to 10 mol %. The results presented in this study may provide new insights to the problem of synthesizing more single-phase multiferroic materials which will hopefully lead to rich and fascinating fundamental physics.

11

Zderzeniowe metody precypitacji kryształów do zastosowań farmaceutycznych

Pindur K., Pawełczyk R.

Przemysł Chemiczny

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2008

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T. 87, nr 11

1118-1121

12

Monitoring Structural Transformations in Crystals. Part 10. Monitoring Molecular and Crystal Structures During a Yang Photocyclization Reaction – Comparative Studies

Turowska-Tyrk I., Łabęcka I., Scheffer J., Xia W.

Polish Journal of Chemistry

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2007

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Vol. 81, nr 5-6

813-824

EN

Structural changes in a crystal, brought about by the Yang photocyclization of the 2-(4-carboxybenzoyl)-2-methyl-endo-bicyclo[2.1.1]hexyl salt with (S)-(–)--phenylethylamine, were monitored by means of X-ray structure analysis. The changes taking place in the reaction centre, as well as changes inmolecular orientation and cell constants are discussed. Analysis of the geometrical parameters describing the reaction centre enabled an evaluation of the possibility of formation of the opposite enantiomer in a crystal. The results are compared with data for other intramolecular photochemical reactions.

13

Właściwości optyczne kryształów występujących w miodzie pszczelim

Bakier S.

Inżynieria Rolnicza

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2003

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R. 7, nr 8

19--25

PL

Praca stanowi próbę opisu właściwości optycznych kryształów powstających w trakcie krystalizacji w miodzie pszczelim. Badania prowadzono wykorzystując interferometrię birefrakcyjną w polu prążkowym. W wyniku pomiarów stwierdzono, że wszystkie kryształy występujące w miodzie pszczelim wykazują dwójłomność optyczną o charakterze dodatnim. Wyznaczono położenie osi optycznej, mikrokryształów oraz wartość dwójłomności optycznej, nadzwyczajnego i zwyczajnego współczynnika załamania światła.

EN

An attempt was made to describe the optical characteristics of the crystals arising at granulation of bee honey. Birefractional interferometry in the striated field was applied in the tests. The measurement results proved that all the crystals appearing in bee honey were characterized by optical birefringence of positive nature. The orientation of microcrystal optical axis, the value of optical birefringence as well as simple and extraordinary light refraction coefficients were determined.

14

The morphology of crystals of a metastable anthracene phase, formed during their growth from the vapour phase

Różycka-Sokołowska E., Marciniak B., Pawliuk W.

Prace Naukowe. Chemia / Wyższa Szkoła Pedagogiczna w Częstochowie

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2001

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Vol. 5

57--65

15

Influence of hydrodynamics on kinetics of crystal growth

Jakubczyk M., Kopyciak G.

Prace Naukowe. Chemia / Wyższa Szkoła Pedagogiczna w Częstochowie

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2001

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Vol. 5

21--26

16

Badanie szerokości obszaru metastabilnego roztworów wzrostowych fluorantenu w trichloroetylenie

Kończyk J., Balińska A., Marciniak B.

Prace Naukowe. Chemia / Wyższa Szkoła Pedagogiczna w Częstochowie

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2001

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Vol. 5

47--56

17

A kinetic theory of crystal growth from aqueous solutions

Jakubczyk M.

Prace Naukowe. Chemia / Wyższa Szkoła Pedagogiczna w Częstochowie

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2001

|

Vol. 5

15--19

EN

The process of the crystal growth kinetics was investigated using the Fokker-Planck equation. The use of the diffusion Fick equation to relate the surface concentration and diffusion requires the use of the modified surface diffusion coefficient which is D = Ds( 1+o(β) where: Ds - is a diffusion coefficient witch the absence of adsorption and desorption, β =1/ξTD is a ratio of relation time characterizing the diffusion surface (1/β)and desorption TD.

18

Investigation of the Ln-Ni-Zn ternary systems

Pavlyuk W., Opainych I., Kevorkov D., Bodak O., Kozioł J. J., Rożdżyńska-Kiełbik B., Bala H.

Prace Naukowe. Chemia / Wyższa Szkoła Pedagogiczna w Częstochowie

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1999

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Vol. 4

165--171

EN

The isothermal section of Ln-Ni-Zn systems (Ln=La, Ce and Er) at 470 K has been investigated by X-ray phase analysis. The crystal structure of ternary compounds formed has been determined by single crystal and powder X-ray diffraction analysis.

PL

Za pomocą analizy rentgenowskiej badano w temp. 470 K przekrój izotermiczny układów Ln-Ni-Zn, gdzie Lo = La, Ce i Er. Strukturę krystaliczną utworzonych trójskładnikowych związków określono wykorzystując metody rentgenowskie badań pojedynczych kryształów i próbek polikrystalicznych.

19

High energy ion implatation profiles

Krynicki J., Puton J., Oleniak J., Warchoł S., Rzewuski H.

Nukleonika

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1999

|

Vol. 44, nr 1

3-13

EN

A new computer program for depth distribution calculations of high energy ions implanted into solids has been presented. It provides a possibility of obtaining any shape of the implanted ion profiles for high energy ions assuming, that the correlation between the Rp and ΔRp is known. In particular, it provides high computer efficiency while maintaining a high degree of accuracy. To ilustrate applicability and reliability of the program a number of representative calculations have been performed. High energy Sb{indeks górny]+ ion implantation into Si crystals was performed for the case of flat and linear implantation profiles. Rutherford Backscattering Spectroscopy has been used to determine depth distributions of the implanted ions. It was found that a very good agreement is held between the assumed theoretical profiles and measured ion distributions. The possible fitting errors manifested by the program are considerably smaller than the accuracy of the method of measurement and the precision of the implantation technique. The experimental results confirm a possibility of the effective application of the high energy ion implantation technique for producing a required distribution of implanted ions in a thin layer of a crystal.

PL

Przedstawiono nowy program komputerowy pozwalający na obliczenie głębokościowego rozkładu w kryształach implantowanych jonów o wysokiej energii. Umożliwia on otrzymanie dowolnego profilu, jeśli tylko znana jest zależność między Rp i ΔRp dla tych jonów. Program zapewnia wysoką wydajność komputera, przy zachowaniu wysokiej dokładności obliczeń. Dla zilustrowania stosowalności i niezawodności przedstawionego programu przeprowadzono stosowne obliczenia. Dokonano również implantacji wysokoenergetycznych jonów Sb[indeks górny]+ do kryształów Si, dla przypadku profilu płaskiego i liniowego. Rozkład głębokościowy implantowanych jonów zmierzony został metodą RBS. Stwierdzono bardzo dobrą zgodność między profilami założonymi teoretycznie i zmierzonymi doświadczalnie. Możliwe błędy dopasowania, wynikające z nowego programu są znacznie mniejsze niż dokładność metody pomiarowej i precyzja techniki implatancyjnej. Wyniki eksperymentalne potwierdziły możliwość zastosowania techniki implantacji jonów o wysokiej energii do uzyskania wymaganego rozkładu jonów domieszki w powierzchniowej warstwie implantowanego kryształu.

20

Brine paleocurrents reconstructed from orientation of the gypsum crystals on the Miechów Upland, southern Poland

Roman A.

Biuletyn Państwowego Instytutu Geologicznego

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1999

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nr 387

60--62