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1

Solid State Synthesized YVO4:Dy3+/ SiO2 Composites: Microstructures and Optical Characteristics

Rafiaei S. M.

Archives of Metallurgy and Materials

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2018

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Vol. 63, iss. 1

199--202

EN

In this paper YVO4:Dy3+ was synthesized via solid state method at 1100°C and effects of different quantities of SiO2 particles on microstructure and photoluminescence properties were investigated in details. To study the microstructure and properties of these composites XRD, SEM, TEM, HRTEM, XPS and PL equipments were employed. It was found that via addition of SiO2 particles to YVO4:Dy3+ phosphors, strong bonding is made between SiO2 particles and phosphors. Furthermore, based on stronger electronegativity of Si 2p element compared to Y 3d and V 2p elements, increase of SiO2 causes the increase of binding energy. Moreover, this research showed that the addition of 10 wt% SiO2 particles to YVO4:Dy3+ material enhances the excitation and emission luminescence properties, significantly. Further increase of SiO2 particles results in suppress of emission intensity.

2

Synthesis of barium titanate piezoelectric ceramics for multilayer actuators (MLAs)

Biglar M., Stachowicz F., Trzepieciński T., Gromada M.

Acta Mechanica et Automatica

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2017

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Vol. 11, no. 4

275--279

EN

In this paper the characteristics of BaTiO3 ceramics synthesized by solid state method is presented. In order to receive the monophase ceramics the double activation and calcination were applied. A spray drier was used to granulate the powder of BaTiO3. Isostatic and uniaxial pressing were applied to manufacture the barium titanate pellets. The properties of fabricated BaTiO3 ceramics were determined at different stages of production. After the sintering phase, the hardness, the bending strength, the fracture toughness, and the coefficient of thermal expansion of barium titanate sinter were estimated. The BaTiO3 powder is characterized by spherical grains and the average size of 0.5 μm. The small value of the specific surface area of granulate ensured good properties of material mouldability and finally allowed to receive sinters of high density

3

Effect of flux compounds on the luminescence properties of Eu3+ doped YBO3 phosphors

Rafiaei S. M.

Materials Science Poland

|

2016

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Vol. 34, No. 4

780--785

EN

In this investigation, Eu3+ doped YBO3 phosphors were synthesized by conventional solid state method at 1100°C under atmosphere condition. Meanwhile, different amounts of LiCl, BaCl2 and CaCl32 were used as the flux compounds to modify the morphology of the phosphor particles and also final luminescent properties. It was concluded that even small amounts of fluxes play a vital role in the growth of particles. Then the emission and excitation photoluminescence spectra were measured respectively at λexc = 240 nm and λem = 610 nm and it was found that using 2 wt.% of flux compounds has a significant influence on the emission intensity of YBO3 phosphors.

4

Solid state friction stir welding using square groove butt joint

Thamizhmanii S., Mohideen R., Mujahid A., Zaidi A., Hasan S.

Journal of Achievements in Materials and Manufacturing Engineering

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2015

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Vol. 73, nr 2

118--123

EN

Purpose: of this paper is to high light the application of Friction Stir Welding (FSW) process using square butt joint. Design/methodology/approach: The design adopted was tool spindle speed, tool plunge depth and transverse movement of the work piece. Findings: The findings are encouraging. It is possible to increase the strength of the joint by 22.45% from the basic tensile strength. The optimum tensile stress obtained was at spindle speed of transverse speed of 700 RPM at transverse speed 325 mm/min taking into consideration the fracture of the materials. The optimum travel speed for the spindle speed 700 RPM is 325 mm/min, this is because the heat generation and the time for the material to joint was increased. But the 200 mm/min is not optimum for the spindle speed 700 rpm because, there is too much heat generation and the welded part become soft by the welding. When there is not enough heat generated, the stir between materials or part will not occur or not properly welded. Research limitations/implications: The limitations in this research were proper fixture. Machine should have variable tool rotation instead of fixed machine spindle speed. Practical implications: It is possible to weld by FSW process and not tested in any application. Originality/value: The research on FSW The limitations in this research were proper fixture. Machine should have variable tool rotation instead of fixed machine spindle speed. is upcoming project and not much work done in this field. Using square shaped joint unique and no references so far using this square groove. Many of the research were by straight butt joint.

5

Odpowiedniość równań mikropolarnej teorii mieszanin i termodyfuzji

Kubik J.

Roczniki Inżynierii Budowlanej

|

2012

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z. 12

21--24

EN

The mass and momentum balances in micropolar mixture theory and thermodiffusion is analysed. One can conclude that not only local and global mass balances should be fulfilled but also local and global inertia moment should be considered. As the consequence we should make similar generalization in reminding balance.

6

Wpływ ilości reduktora na proces nieizotermicznej redukcji rud żelaza w zakresie temperatury 800÷1350°C 1

Mróz J., Bitowt J.

Hutnik, Wiadomości Hutnicze

|

2012

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Vol. 79, nr 7

470--475

PL

W warunkach pracy wielkiego pieca istnieją obszary o zróżnicowanym stosunku ilości reduktora (koksu) do ilości redukowanej rudy (tlenków żelaza). Wpływa to zarówno na szybkość procesu redukcji, jak i jakość powstających faz mineralogicznych oraz temperatury topnienia tych faz. W pracy badano wpływ ilości reduktora na przebieg redukcji rudy hematytowej (RCC) oraz koncentratów magnetytowych: kowdorskiego (MK) i lebiedeńskiego (ML), prowadzonej w sposób nieizotermiczny w zakresie temperatur 800÷1350°C. Stwierdzono, że w przypadku niewystarczającej ilości reduktora mogą powstawać duże ilości łatwotopliwej fazy mineralogicznej w wyniku małej szybkości redukcji i niskiego stopnia zredukowania rudy.

EN

In the blast furnace operating conditions, there are areas with different ratio of the reducer (coke) to the iron ores (iron oxides) to be reduced. This affects both the speed of the reduction process and the quality of the resulting mineralogical phases and the smelting temperatures of these phases. In the work the quantities of reducer on the course of reduction of hematite ore (RCC) and magnetite concentrates: kowdorski (MK) and lebiedenski (ML) were investigated. The reduction process was conducted in non-isothermal way in the temperature range 800÷1350 °C. It was stated that in the case of insufficient amount of reducer a great quantities of fusible mineralogical phases are formed as a result of small reduction rate and low reduction degree of iron ores.

7

Działania światła lasera na powierzchnię ciała stałego

Kubik J.

Roczniki Inżynierii Budowlanej

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2010

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z. 10

31--34

EN

In the paper, a laser light flow by layers of the mural paintings is analyzed. Each layer adsorbs and reflects laser light, allowing the identification of the underlying surfaces of mural paintings

8

The Nature of Hydrogen Bonding in Selected Hydrazide Derivatives Investigated via Static Models and Car-Parrinello Molecular Dynamics

Jezierska A., Novič M., Panek J. J.

Polish Journal of Chemistry

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2009

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Vol. 83, nr 5

799-819

EN

The geometric and spectrocopic properties of 2-hydroxy-thiobenzhydrazide and 2-hydroxy-benzhydrazide were investigated within the frame work of Density Functional Theory (DFT). Special attention was devoted to the description and analysis of intra- and intermolecular hydrogen bonds. The choice of the compounds was dictated by their structural similarity and the presence of two types of hydrogen bridges: O–H...S (in 2-hydroxy-thiobenzhydrazide, less common) and O–H...O (in 2-hydroxy-benzhydrazide). The latter could be classified as a low-barrier hydrogen bond (LBHB). First the DFT method was used to obtain the geometric parameters for the monomeric and dimeric forms of the compounds at various levels of theory. Then the binding energy was calculated for the dimeric forms to estimate the strength of the intermolecular hydrogen bonds. Atoms in Molecules (AIM) theory was applied to show quantitatively how the formation of the intermolecular hydrogen bonds affects the strength of the intramolecular hydrogen bonds. The electron density and its Laplacian were calculated for the bond critical points defining the H-bridges. Car-Parrinello molecular dynamics (CPMD) was then used to investigate the changes in the geometric parameters as a function of simulation time. This part of the computational study was performed in vacuo and in the solid state. The vibrational properties of the investigated hydrazides were obtained via Fourier transform of the autocorrelation functions of the dipole moment and atomic velocity. It was found that the formation of the intermolecular H-bonds does not significantly affect the strength of the intramolecular H-bonds. There fore inductive and steric effects out side the immediate vicinity of the intramolecular bridge have minor influence on its investigated properties. The application of CPMD gave a more detailed picture of the bridged protons’ dynamics. The computational results agree with available experimental data. The influence of the intermolecular hydrogen bonding net work and non-bonded crystal field interactions on the vibrational features of the investigated molecules is demonstrated and discussed.

9

Modelling the concentration and dimensional changes in the structural constituents of vermicular graphite cast iron on cooling within the range of solidus-eutectoid temperature

Kapturkiewicz W., Burbelko A. A., Fraś E.

Archives of Foundry Engineering

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2008

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Vol. 8, iss. 1 spec.

179--182

EN

A mathematical model and a simulation program have been developed to trace changes in the structure of Fe-C alloy on cooling from the solidus temperature to the temperature of eutectoid transformation. A simplified schematic representation of the process can be referred to the cast iron with vermicular graphite. The numerical experiments using the newly developed program have proved a significant effect of the cooling conditions and structure refinement degree (the dimensions of austenite) on the concentration field in austenite and, consequently, on the dimensional changes of graphite within the examined cooling range. The developed methods of modelling the process of transformation enable including the procedure into a complex software operating in a system reproducing in real manner the casting configuration, while the obtained results indicate an important effect of thermophysical parameters and heat transfer process on final alloy structure.

10

Zastosowanie spektroskopii 29Si NMR do badań polimerów krzemoorganicznych

Cypryk M.

Polimery

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2007

|

T. 52, nr 10

730-735

PL

Przedstawiono krótki przegląd zastosowań współczesnych technik 29Si NMR w badaniach materiałów polimerowych opartych na krzemie. Uwzględniono przy tym warianty badań w roztworze oraz w stanie stałym. Pierwszy z tych wariantów wykorzystuje się zarówno do charakterystyki i identyfikacji produktów (polisiloksanów, polisilanów), jak i do bardziej subtelnych badań struktury oraz dynamiki łańcucha a także do badań mechanizmu i kinetyki reakcji polimeryzacji. Wariant NMR stanu stałego służy natomiast do oceny orientacji, dynamiki i zmian konformacyjnych łańcuchów polimerów wewnątrz bądź na powierzchni materiałów krzemoorganicznych.

EN

A short review of applications of modern 29Si NMR techniques in the investigations of silicon based polymeric materials is presented. Two variants of investigations i.e. in liquid state and solid-state NMR were taken into account. The first one is used for characteristics and identification of the products (polysiloxanes, polysilanes) as well as for fine investigations of the structure and dynamics of polymer chain and mechanism and kinetics of polymerization reactions. Solid-state NMR is used for the evaluation of orientation, dynamics and conformational changes of polymer chains inside or on the surface of organosilicon material.

11

A review on advances of high-resolution solid state NMR spectroscopy in structural studies of polymer/clay nanocomposites

Olejniczak S., Kaźmierski S., Pallathadka P. K., Potrzebowski M. J.

Polimery

|

2007

|

T. 52, nr 10

713-721

EN

The new applications of one- and two-dimensional solid state (SS) NMR spectroscopy for investigations of polymer/clay nanocomposites were discussed. 1D SS NMR spectroscopy is applied to evaluate the structural and dynamic properties of composites. 2D SS NMR is used for detailed studies on polymer-nanofiller contacts what let understand the mechanism of these interactions on the molecular level.

PL

Omówiono nowe zastosowania jedno- (1D) i dwuwymiarowej (2D) spektroskopii magnetycznego rezonansu jądrowego w fazie stałej (SS NMR) w badaniach nanokompozytów polimer/glinka. Spektroskopię 1D SS NMR wykorzystuje się do oceny strukturalnych i dynamicznych właściwości kompozytów, a spektroskopię 2D - do szczegółowych badań oddziaływań polimer-nanonapełniacz, co pozwala na zrozumienie mechanizmu tych oddziaływań.

12

The effect of different starting materials on the synthesis of lithium triborate

Depci T., Ozbayoglu G., Yilmaz A.

Physicochemical Problems of Mineral Processing

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2007

|

Vol. 41

101-105

EN

Lithium triborate (LiB3O5) was synthesized using different starting materials. The effect of these materials on the phase purity of LiB3O5 was investigated in each case. Identification and characterizations of the products were carried out by powder X-ray diffraction (XRD) and infrared (IR) analyses. The present study showed that the starting materials play an important role in the synthesis of lithium triborate with respect to phase impurity.

PL

Syntezowano trójboran litu (LiB3Os) stosując różne materiały wyjściowe. Badano wpływ tych materiałów na końcową czystość LiB3O5. Identyfikowano i charakteryzowano produkty syntezy za pomocą dyfrakcji rentgenowskiej (XRD) oraz analizy spektroskopowej w podczerwieni (IR). Badania wykazały, że wyjściowe materiały grają ważna rolę w czystości syntezowanego trójboranu litu.

13

Metody badań własności wielkopiecowego wsadu żelazonośnego

Mróz J.

Hutnik, Wiadomości Hutnicze

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2004

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Vol. 71, nr 2

54-59

PL

W artykule przedstawiono obecny stan unormowań dotyczących wymagań jakościowych dla wielopiecowego wsadu żelazonośnego, stawianych w nowoczesnej technologii wielkopiecowej. Omówiono normy PN-ISO dotyczące badań własności rud, spieków i grudek w stanie stałym, oraz metody nowo opracowywane i proponowane dla oceny jakości materiałów w zakresie mięknięcia- topnienia i wykraplania faz ciekłych.

EN

The paper describes the current state of standards concerning quality requirements of iron-bearing blast furnace charge in modern blast - furnace technology. The PN-ISO standards for testing properties of ores, sinters and pellets in solid are presented as well as some methods being newly developed and proposed for the assesment of material quality in the aspect of softening - melting and precipitating of liquid phases.

14

Porous glasses as a host for solid state tunable lasers in the visible as a means for fluorescence diagnostics and photodynamic therapy.

Reisfeld R, Yariv E.

Optica Applicata

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2000

|

Vol. 30, nr 4

481-490

EN

Lasers prepared by incorporation of the active dyes into porous glasses are described. The background of the use of lasers for photodynamic therapy and diagnostics is outlined. The role of hematoporphyrin and hypericin in creation of singlet oxygen which destroys the malignant tissues, is explained. The lasers, based on sol-gel technology, incorporated by several perylimide and pyrromethane dyes emit in the suitable range in which the hematoporphyrin is excited. These compact lasers may replace, in the future, the vapour and the liquid lasers. The synthesis and the spectroscopic properties of the laser are described.

15

Solid state NMR spectroscopy as a tool to investigation of structure and dynamics of amino acids and model peptides

Ganicz K.

Bulletin of the Polish Academy of Sciences. Chemistry

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2000

|

Vol. 48, No. 1

57-76

EN

The paper describes new approaches to investigate amino acids and peptides in the solid state employing modern NMR spectroscopy. The application of C and N principal elements of the chemical shift tensors to analysis of local environment of peptide unit, carboxylate group and amine group is discussed. The application of NMR techniques to investigate hydrogen bonding pattern is described. Molecular dynamics and deuterium NMR spectroscopy are presented. The sequences to measure the intra- and intermolecular distances as well as torsional angles in homo- and heteronuclear systems are discussed.

16

Interaction of convection and solidification at fluid-solid-interfaces

Bunk M., Bühler L., Ehrhard P., Müller U.

Zeszyty Naukowe Politechniki Świętokrzyskiej. Mechanika

|

1999

|

Z. 67

45--59

EN

Phase change from the liquid to the solid state is of crucial importance for many natural and technical processes, such as lava flow, casting and welding of metallic materials, crystal growth from semiconductor melts. A phase transition “liquid to solid” can initiate convection by the release of latent heat, density changes during solidification, segregation and concentration of solute at the phase change interface. Convection in the liquid phase induced by temperature and/or concentration gradients can lead to feed back effects, which may modify significantly the thermal and solutal environment at the interface and thereby determine the local solidification process. The interaction of convection and solidification is demonstrated by three striking examples; Bénard convection, directional solidification, gravity driven spreading flows.

17

Laboratoryjny bioreaktor bębnowy do hodowli drobnoustrojów na podłożach stałych "BIOSOL"

Leśniak W., Pietkiewicz J.J., Gąsiorek E., Podgórski W.

Zeszyty Naukowe. Inżynieria Chemiczna i Procesowa / Politechnika Łódzka

|

1999

|

Z. 26

259-264

PL

Przedstawiono opis budowy laboratoryjnego bioreaktora bębnowego BIOSOL służącego do badania tlenowych i beztlenowych hodowli drobnoustrojów na podłożach stałych z okresowym lub ciągłym mieszaniem. Podstawowym zespołem bioreaktora jest obracający się w pozycji horyzontalnej bęben zbudowany z rury szklanej zamkniętej płaskimi pokrywami wykonanymi ze stali kwasoodpornej. Bioreaktor zamontowano na specjalnej podstawie i wyposażono w układy pomiarowe i regulacyjne umożliwiające kontrolę podstawowych parametrów prowadzonego w nim bioprocesu.

EN

Construction of a new lab rotating drum bioreactor BIOSOL is demonstrated. It is used in the lab scale studies on fermentation and cultivation of aerobic and anaerobic microorganisms carried out on moist solid substrates.

18

Selenium-77 high resolution solid state NMR studies of organoselenium compounds

Potrzebowski M. J.

Bulletin of the Polish Academy of Sciences. Chemistry

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1998

|

Vol. 46, No. 1

61-74

EN

The review describes the high resolution solid state NMR studies of organoselnium compounds carried out in NMR Laboratory of the Polish Academy of Sciences, Łódź. The review is organized into sections. The X-ray crystallography and 775e solid tate NMR spectroscopy as complementary tools for studies of polymorphs and moleclar packing effect as well as some aspects regarding the ambiguities related to proper hoice of the space group are discussed in Section 2. Section 3 shows recent progress in studies of phosphoroorganic diselenides and relationship between the molecular structure and 775e effective dipolar/chemical shift parameters Tii. It is shown that anisotropy and asymmetry parameters reflect the changes of local environment of selenium centers. The relationship between ,fl and Se-Se bond strength is discussed. Moreover, the studies show the great sensitivity of T(33) parameter to changes of geometry for S=P-Se-Se-P=S unit.; is speculated that T(33) is aligned in plane of P-Se bond. The significant differences in values of isotropic chemical shifts E;so are mostly caused by T(33) component.

19

NMR spectroscopic investigations on molecular dynamics in the solid state

Domalewski W., Riddell F. G., Stefaniak L.

Bulletin of the Polish Academy of Sciences. Chemistry

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1998

|

Vol. 46, No. 1

35-59

EN

Representative examples of various large amplitude solid state dynamic phenomena are given. Several NMR techniques suitable for quantitative investigations of such processes are presented. The compability between X-ray diffraction and solid state NMR spectroscopy is pointed out. Common labile character of organic solids is discussed.